WorldWideScience

Sample records for dragonfly radiation reflects

  1. Limiting hydrophobic behavior and reflectance response of dragonfly and damselfly wings

    Science.gov (United States)

    Aideo, Swati Nawami; Mohanta, Dambarudhar

    2016-11-01

    In this work, through water contact angle (CA) measurements, we explore hydrophobic behavior of different parts of the hind wings of a dragonfly, Gynacantha Dravida and of a damselfly, Pseudagrion Microcephalum. As we move from the basal to distal region, the contact angle (θ) was found to vary in the range of 120-136° for both the species. Moreover, the wing of the dragonfly was seen to be more hydrophobic than that of the damselfly one. An attempt has also been made to link roughness factor (rφ) and solid-water fraction (φ) through the simplified Wenzel and Cassie-Baxter models. We noticed that, rφ and φ tend to follow a linear relation that gives rφ = 1.47 in the limit, Δθ segment was believed to be stronger than that of the basal part, the edge parts of the dragonfly and damselfly wings exhibited exponential associated growing trends with increasing wavelength. The relative reflectance response, corresponding to ∼494 nm and 370 nm peaks, gets nearly doubled for the edge specimen as compared to the distal and basal parts. The edge- specimen, which comprises of rectangular shaped, periodic microstructures, displayed carotenoid based two broad peak maxima at ∼422 nm and ∼494 nm. The surface roughness which arises through the distribution of oblate-shaped nano-fibrils is believed to be the basis of sub-surface volume scattering. Interrelating nanostructure surface roughness based wettability and reflectance characteristics would provide new insights on structure-property relationship in naturally available soft matter systems including templates of biological origin.

  2. Degrees of polarization of reflected light eliciting polarotaxis in dragonflies (Odonata), mayflies (Ephemeroptera) and tabanid flies (Tabanidae).

    Science.gov (United States)

    Kriska, György; Bernáth, Balázs; Farkas, Róbert; Horváth, Gábor

    2009-12-01

    With few exceptions insects whose larvae develop in freshwater possess positive polarotaxis, i.e., are attracted to sources of horizontally polarized light, because they detect water by means of the horizontal polarization of light reflected from the water surface. These insects can be deceived by artificial surfaces (e.g. oil lakes, asphalt roads, black plastic sheets, dark-coloured cars, black gravestones, dark glass surfaces, solar panels) reflecting highly and horizontally polarized light. Apart from the surface characteristics, the extent of such a 'polarized light pollution' depends on the illumination conditions, direction of view, and the threshold p* of polarization sensitivity of a given aquatic insect species. p* means the minimum degree of linear polarization p of reflected light that can elicit positive polarotaxis from a given insect species. Earlier there were no quantitative data on p* in aquatic insects. The aim of this work is to provide such data. Using imaging polarimetry in the red, green and blue parts of the spectrum, in multiple-choice field experiments we measured the threshold p* of ventral polarization sensitivity in mayflies, dragonflies and tabanid flies, the positive polarotaxis of which has been shown earlier. In the blue (450nm) spectral range, for example, we obtained the following thresholds: dragonflies: Enallagma cyathigerum (0%

  3. Dragonflies and Fireflies

    Science.gov (United States)

    Mannlein, Sally

    2009-01-01

    Most first-graders are interested in insects. In this article, the author describes a lesson, "Dragonflies and Fireflies," which is a first-grade lesson showing drawing, symmetry, neighboring colors (analogous) and watercolor techniques.

  4. Recovery of endemic dragonflies after removal of invasive alien trees.

    Science.gov (United States)

    Samways, Michael J; Sharratt, Norma J

    2010-02-01

    Because dragonflies are very sensitive to alien trees, we assessed their response to large-scale restoration of riparian corridors. We compared three types of disturbance regime--alien invaded, cleared of alien vegetation, and natural vegetation (control)--and recorded data on 22 environmental variables. The most significant variables in determining dragonfly assemblages were percentage of bank cover and tree canopy cover, which indicates the importance of vegetation architecture for these dragonflies. This finding suggests that it is important to restore appropriate marginal vegetation and sunlight conditions. Recovery of dragonfly assemblages after the clearing of alien trees was substantial. Species richness and abundance at restored sites matched those at control sites. Dragonfly assemblage patterns reflected vegetation succession. Thus, initially eurytopic, widespread species were the main beneficiaries of the removal of alien trees, and stenotopic, endemic species appeared after indigenous vegetation recovered over time. Important indicator species were the two national endemics (Allocnemis leucosticta and Pseudagrion furcigerum), which, along with vegetation type, can be used to monitor return of overall integrity of riparian ecology and to make management decisions. Endemic species as a whole responded positively to restoration, which suggests that indigenous vegetation recovery has major benefits for irreplaceable and widespread generalist species.

  5. K.A.Subramanian (2005) Dragonflies and Damselflies of Peninsular ...

    Indian Academy of Sciences (India)

    K A Subramaniam

    K.A.Subramanian (2005) Dragonflies and Damselflies of Peninsular India-A Field Guide. .... This dragonfly is very common near marshes, ponds and big wells. .... black and yellow dragonfly with amber coloured wings. Male: Eyes: Eyes are.

  6. Reflections concerning radiation protection philosophy

    International Nuclear Information System (INIS)

    Seelentag, W.

    1981-01-01

    Critical philosophy also includes observations of the technical amplified senses make, i.e. the application of accessory instruments, measuring instruments and statistic methods. The application of this philosophy is, among other things, referred to when taking the linear dose response relationship for stochastic radiation effects as an example. (DG) [de

  7. Theory of relativistic radiation reflection from plasmas

    Science.gov (United States)

    Gonoskov, Arkady

    2018-01-01

    We consider the reflection of relativistically strong radiation from plasma and identify the physical origin of the electrons' tendency to form a thin sheet, which maintains its localisation throughout its motion. Thereby, we justify the principle of relativistic electronic spring (RES) proposed in [Gonoskov et al., Phys. Rev. E 84, 046403 (2011)]. Using the RES principle, we derive a closed set of differential equations that describe the reflection of radiation with arbitrary variation of polarization and intensity from plasma with an arbitrary density profile for an arbitrary angle of incidence. We confirm with ab initio PIC simulations that the developed theory accurately describes laser-plasma interactions in the regime where the reflection of relativistically strong radiation is accompanied by significant, repeated relocation of plasma electrons. In particular, the theory can be applied for the studies of plasma heating and coherent and incoherent emissions in the RES regime of high-intensity laser-plasma interaction.

  8. Pigments which reflect infrared radiation from fire

    Science.gov (United States)

    Berdahl, Paul H.

    1998-01-01

    Conventional paints transmit or absorb most of the intense infrared (IR) radiation emitted by fire, causing them to contribute to the spread of fire. The present invention comprises a fire retardant paint additive that reflects the thermal IR radiation emitted by fire in the 1 to 20 micrometer (.mu.m) wavelength range. The important spectral ranges for fire control are typically about 1 to about 8 .mu.m or, for cool smoky fires, about 2 .mu.m to about 16 .mu.m. The improved inventive coatings reflect adverse electromagnetic energy and slow the spread of fire. Specific IR reflective pigments include titanium dioxide (rutile) and red iron oxide pigments with diameters of about 1 .mu.m to about 2 .mu.m and thin leafing aluminum flake pigments.

  9. Structural Analysis of a Dragonfly Wing

    NARCIS (Netherlands)

    Jongerius, S.R.; Lentink, D.

    2010-01-01

    Dragonfly wings are highly corrugated, which increases the stiffness and strength of the wing significantly, and results in a lightweight structure with good aerodynamic performance. How insect wings carry aerodynamic and inertial loads, and how the resonant frequency of the flapping wings is tuned

  10. Workplace diaries promoting reflective practice in radiation therapy

    International Nuclear Information System (INIS)

    Chapman, Naomi; Dempsey, Shane E.; Warren-Forward, Helen M.

    2009-01-01

    Competency standards usually describe that radiation therapists are expected to display characteristics of reflective practice. Many radiation therapists may be unequipped to undertake reflective practice or produce evidence of reflective practice due to limited understanding of the process. There are many models to guide practitioners in their reflective journeys, however, the literature describing reflective practice can appear confusing. This paper will discuss the role of reflective practice, provide a definition for reflective practice and define concepts central to reflective journaling or workplace diaries. The paper will offer practical advice to increase radiation therapists knowledge and skills in the use of reflective workplace diaries.

  11. Workplace diaries promoting reflective practice in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Naomi [Medical Radiation Science, Faculty of Health Science, Box 16 Hunter Building, University of Newcastle, Callaghan, NSW 2308 (Australia)], E-mail: naomi.chapman@newcastle.edu.au; Dempsey, Shane E. [Medical Radiation Science, Faculty of Health Science, Box 16 Hunter Building, University of Newcastle, Callaghan, NSW 2308 (Australia)], E-mail: shane.e.dempsey@newcastle.edu.au; Warren-Forward, Helen M. [Medical Radiation Science, Faculty of Health Science, Box 16 Hunter Building, University of Newcastle, Callaghan, NSW 2308 (Australia)], E-mail: helen.warren-forward@newcastle.edu.au

    2009-05-15

    Competency standards usually describe that radiation therapists are expected to display characteristics of reflective practice. Many radiation therapists may be unequipped to undertake reflective practice or produce evidence of reflective practice due to limited understanding of the process. There are many models to guide practitioners in their reflective journeys, however, the literature describing reflective practice can appear confusing. This paper will discuss the role of reflective practice, provide a definition for reflective practice and define concepts central to reflective journaling or workplace diaries. The paper will offer practical advice to increase radiation therapists knowledge and skills in the use of reflective workplace diaries.

  12. Synthesis of concentric circular antenna arrays using dragonfly algorithm

    Science.gov (United States)

    Babayigit, B.

    2018-05-01

    Due to the strong non-linear relationship between the array factor and the array elements, concentric circular antenna array (CCAA) synthesis problem is challenging. Nature-inspired optimisation techniques have been playing an important role in solving array synthesis problems. Dragonfly algorithm (DA) is a novel nature-inspired optimisation technique which is based on the static and dynamic swarming behaviours of dragonflies in nature. This paper presents the design of CCAAs to get low sidelobes using DA. The effectiveness of the proposed DA is investigated in two different (with and without centre element) cases of two three-ring (having 4-, 6-, 8-element or 8-, 10-, 12-element) CCAA design. The radiation pattern of each design cases is obtained by finding optimal excitation weights of the array elements using DA. Simulation results show that the proposed algorithm outperforms the other state-of-the-art techniques (symbiotic organisms search, biogeography-based optimisation, sequential quadratic programming, opposition-based gravitational search algorithm, cat swarm optimisation, firefly algorithm, evolutionary programming) for all design cases. DA can be a promising technique for electromagnetic problems.

  13. On the radiation accompanying volume reflection

    International Nuclear Information System (INIS)

    Bandiera, L.; Bagli, E.; Berra, A.; Bolognini, D.; Dalpiaz, P.; Della Mea, G.; De Salvador, D.; Guidi, V.; Hasan, S.; Lietti, D.; Mazzolari, A.

    2013-01-01

    The electromagnetic radiation emitted by 120 GeV/c volume-reflected electrons in a bent silicon crystal has been investigated at CERN SPS-H4 beamline. The trajectories of electrons crossing a silicon strip-like crystal have been reconstructed through a telescope system based on high precision micro-strip detectors. The experimental setup was also equipped with a spectrometer and an electromagnetic calorimeter to measure the energy loss of the particles under volume reflection condition. Such a system enabled to record the full photon spectrum up to the nominal energy of the beam. Experimental results were compared to recently developed theoretical approaches based on the quasi-classical operators method of Baier and Katkov

  14. Coherent reflectivity using white synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Panzner, Tobias; Sant, Tushar; Pietsch, Ullrich [Universitaet Siegen (Germany). Festkoerperphysik

    2008-07-01

    Using coherent white synchrotron radiation in the hard X-ray region for reflectivity experiments one have access to sample properties on a nanometer scale in principle. To extract the wanted information from the performed measurements so called phase retrieval algorithms are necessary. The authors developed a straight forward simulation program based on a spatial limited atomic flat surface to evaluate the influence of different parameters on the coherent scattered signal in the detector plane. These simulations can explain some interesting features of the measurements and shows unexpected results for the influence of the so called illumination function.

  15. Synchrotron radiation total reflection for rainwater analysis

    International Nuclear Information System (INIS)

    Simabuco, Silvana M.; Matsumoto, Edson

    1999-01-01

    Total reflection X-ray fluorescence analysis excited with synchrotron radiation (SR-TXRF) has been used for rainwater trace element analysis. The samples were collected in four different sites at Campinas City, SP. Standard solutions with gallium as internal standard were prepared for the calibration system. Rainwater samples of 10 μl were putted onto Perspex reflector disk, dried on vacuum and analyzed for 100 s measuring time. The detection limits obtained for K-shell varied from 29 ng.ml -1 for sulfur to 1.3 ng.ml -1 for zinc and copper, while for L-shell the values were 4.5 ng.ml -1 for mercury and 7.0 ng.ml -1 for lead. (author)

  16. A rapid radiative transfer model for reflection of solar radiation

    Science.gov (United States)

    Xiang, X.; Smith, E. A.; Justus, C. G.

    1994-01-01

    A rapid analytical radiative transfer model for reflection of solar radiation in plane-parallel atmospheres is developed based on the Sobolev approach and the delta function transformation technique. A distinct advantage of this model over alternative two-stream solutions is that in addition to yielding the irradiance components, which turn out to be mathematically equivalent to the delta-Eddington approximation, the radiance field can also be expanded in a mathematically consistent fashion. Tests with the model against a more precise multistream discrete ordinate model over a wide range of input parameters demonstrate that the new approximate method typically produces average radiance differences of less than 5%, with worst average differences of approximately 10%-15%. By the same token, the computational speed of the new model is some tens to thousands times faster than that of the more precise model when its stream resolution is set to generate precise calculations.

  17. Dragonflies | 1-Overview | 5-Publications | Indian Academy of ...

    Indian Academy of Sciences (India)

    Two global biodiversity hot spots, namely the eastern Himalayas and the Western Ghats, are in this region. Another biologically rich region, Sri Lanka, is just to the south of the subcontinent. The subcontinent is rich in odonates (damselflies and dragonflies); about 500 species are known. The dragonflies of the region are ...

  18. Modeling and Control of a Dragonfly-Like Robot

    Directory of Open Access Journals (Sweden)

    Micael S. Couceiro

    2010-01-01

    Full Text Available Dragonflies demonstrate unique and superior flight performances than most of the other insect species and birds. They are equipped with two pairs of independently controlled wings granting an unmatchable flying performance and robustness. In this paper, the dynamics of a dragonfly-inspired robot is studied. The system performance is analyzed in terms of time response and robustness. The development of computational simulation based on the dynamics of the robotic dragonfly allows the test of different control algorithms. We study different movements, the dynamics, and the level of dexterity in wing motion of the dragonfly. The results are positive for the construction of flying platforms that effectively mimic the kinematics and dynamics of dragonflies and potentially exhibit superior flight performance than existing flying platforms.

  19. Recovery methods of the dragonfly from irregular initial conditions

    Science.gov (United States)

    Melfi, James; Leonardo, Anthony; Wang, Jane

    We release dragonflies from a magnetic tether in a wide range of initial orientations, which results in them utilizing multiple methods to regain their typical flight orientation. Special focus is placed on dropping them while upside down, as the recovery method used is a purely rolling motion. Filming this stereotypical motion with a trio of high speed cameras at 4000 fps, we capture detailed body and wing kinematics data to determine how the dragonfly generates this motion. By replaying the flights within a computer simulation, we can isolate the significant changes to wing kinematics, and find that it is an asymmetry in the wing pitch which generates the roll. Further investigation demonstrates that this choice is highly dependent upon the state of the dragonfly, and as such our results indicate the dragonfly both tracks its current state, and changes its mid-flight control mechanisms accordingly.

  20. Dragonflies | 1-Overview | 5-Publications | Indian Academy of ...

    Indian Academy of Sciences (India)

    Dragonflies and Damselflies of Peninsular India - A Field Guide ... a checklist of odonates for the region (178 species) and a glossary of technical terms. ... 4 to 6 November 2016 at Indian Institute of Science Education and Research, Bhopal.

  1. Metrology of reflection optics for synchrotron radiation

    International Nuclear Information System (INIS)

    Takacs, P.Z.

    1985-09-01

    Recent years have seen an almost explosive growth in the number of beam lines on new and existing synchrotron radiation facilities throughout the world. The need for optical components to utilize the unique characteristics of synchrotron radiation has increased accordingly. Unfortunately, the technology to manufacture and measure the large, smooth, exotic optical surfaces required to focus and steer the synchrotron radiation beam has not progressed as rapidly as the operational demands on these components. Most companies do not wish to become involved with a project that requires producing a single, very expensive, aspheric optic with surface roughness and figure tolerances that are beyond their capabilities to measure. This paper will review some of the experiences of the National Synchrotron Light Source in procuring grazing incidence optical components over the past several years. We will review the specification process - how it is related to the function of the optic, and how it relates to the metrology available during the manufacturing process and after delivery to the user's laboratory. We will also discuss practical aspects of our experience with new technologies, such as single point diamond turning of metal mirrors and the use of SiC as a mirror material. Recent advances in metrology instrumentation have the potential to move the measurement of surface figure and finish from the research laboratory into the optical shop, which should stimulate growth and interest in the manufacturing of optics to meet the needs of the synchrotron radiation user community

  2. Selective reflection of resonance radiation from excited media

    International Nuclear Information System (INIS)

    Veklenko, B.A.; Gusarov, R.B.; Sherkunov, Yu.B.

    1998-01-01

    According to quantum electrodynamics, the cross section for resonant scattering of radiation on an aggregate of excited atoms can be written as a sum of positive definite terms. This type of structure is not consistent with the Fresnel formulas for the reflection coefficient of radiation from thermally excited media. The difference shows up on a macroscopic level and indicates that semiclassical radiation theory cannot be used. A study of the correlation between elastic scattering and stimulated emission processes clarifies the reason for the discrepancies. The resulting singularities require summing of Feynman diagrams which appear beginning in the sixth order of perturbation theory. A lower bound estimate for the reflection coefficient from a plane layer is given, including processes which violate the statistics of radiation. The contribution of stimulated emission processes caused by the initially scattered photon are examined specifically. An experiment is proposed which would settle the choice of theories

  3. Development of paints with infrared radiation reflective properties

    Directory of Open Access Journals (Sweden)

    Eliane Coser

    2015-06-01

    Full Text Available AbstractLarge buildings situated in hot regions of the Globe need to be agreeable to their residents. Air conditioning is extensively used to make these buildings comfortable, with consequent energy consumption. Absorption of solar visible and infrared radiations are responsible for heating objects on the surface of the Earth, including houses and buildings. To avoid excessive energy consumption, it is possible to use coatings formulated with special pigments that are able to reflect the radiation in the near- infrared, NIR, spectrum. To evaluate this phenomenon an experimental study about the reflectivity of paints containing infrared-reflective pigments has been made. By irradiating with an IR source and by measuring the surface temperatures of the samples we evaluated: color according to ASTM D 2244-14, UV/VIS/NIR reflectance according to ASTM E 903-12 and thermal performance. Additionally, the spectral reflectance and the IR emittance were measured and the solar reflectance of the samples were calculated. The results showed that plates coated with paints containing IR-reflecting pigments displayed lower air temperature on the opposite side as compared to conventional coatings, indicating that they can be effective to reflect NIR and decrease the temperature of buildings when used in roofs and walls.

  4. Reflection, radiation, and interference near the black hole horizon

    International Nuclear Information System (INIS)

    Kuchiev, M.Yu.

    2004-01-01

    The event horizon of black holes is capable of reflection: there is a finite probability for any particle that approaches the horizon to bounce back. The albedo of the horizon depends on the black hole temperature and the energy of the incoming particle. The reflection shares its physical origins with the Hawking process of radiation; both of them arise as consequences of the mixing of the incoming and outgoing waves that takes place due to quantum processes on the event horizon

  5. Reflection Group on 'Ethical Choices in Radiation Protection'

    International Nuclear Information System (INIS)

    Eggermont, G.

    2000-01-01

    As part of SCK-CEN's social sciences and humanities programme, a reflection group on 'Ethical Choices in Radiation Protection' was created. The objectives of the reflection group are (1) to brainstorm on critical issues of radiation protection; (2) to create a discussion forum with a variety os SCK-CEN researchers and external experts; (3) to make value judgements and open questions in radiation protection explicit; (4) to create an output for a topical day or workshop by editing a 'cahier' of contributed articles and discussion reports; (5) to complement the output of the SCK-CEN contribution in international ALARA workshops. The programme, achievements and perspectives of the refection group are summarised

  6. Globally threatened dragonflies (Odonata) in Eastern Africa and ...

    African Journals Online (AJOL)

    This paper presents the status of East African dragonfly species (Odonata) listed globally as threatened on "The IUCN Red List of Threatened Species". The area considered includes Ethiopia, Kenya, Uganda, Burundi, Rwanda, Tanzania and Malawi. From a total of 323 species known from these countries, 31 are listed in ...

  7. Dragonflies (odonata) of Rufiji district, Tanzania with new records for ...

    African Journals Online (AJOL)

    The habitat specialists found in Ngumburuni forest and in the forests of the Kichi and Kiwengoma Hills are globally endangered species and require special attention with regard to conservation. Keywords: dragonflies; coastal forest; Tanzania; conservationJournal of East African Natural History Vol. 95 (2) 2006: pp. 139-162 ...

  8. The Neuronal Control of Flying Prey Interception in Dragonflies

    Science.gov (United States)

    2014-08-19

    Gonzalez-Bellido’s fluorescent dye ( Lucifer -yellow) injections illuminated for the first time the anatomy of the output regions of the TSDNs...out in Cape Cod (MA) to test the effect of bead size(C), and in the Olberg Laboratory (Union College, NY) to test the effect of bead speed by...AFRL-OSR-VA-TR-2014-0193 THE NEURONAL CONTROL OF FLYING PREY INTERCEPTION IN DRAGONFLIES Robert Olberg TRUSTEES OF UNION COLLEGE IN THE TOWN OF

  9. Dragonfly: an implementation of the expand-maximize-compress algorithm for single-particle imaging.

    Science.gov (United States)

    Ayyer, Kartik; Lan, Ti-Yen; Elser, Veit; Loh, N Duane

    2016-08-01

    Single-particle imaging (SPI) with X-ray free-electron lasers has the potential to change fundamentally how biomacromolecules are imaged. The structure would be derived from millions of diffraction patterns, each from a different copy of the macromolecule before it is torn apart by radiation damage. The challenges posed by the resultant data stream are staggering: millions of incomplete, noisy and un-oriented patterns have to be computationally assembled into a three-dimensional intensity map and then phase reconstructed. In this paper, the Dragonfly software package is described, based on a parallel implementation of the expand-maximize-compress reconstruction algorithm that is well suited for this task. Auxiliary modules to simulate SPI data streams are also included to assess the feasibility of proposed SPI experiments at the Linac Coherent Light Source, Stanford, California, USA.

  10. 3D Cloud Radiative Effects on Polarized Reflectances

    Science.gov (United States)

    Cornet, C.; Matar, C.; C-Labonnote, L.; Szczap, F.; Waquet, F.; Parol, F.; Riedi, J.

    2017-12-01

    As recognized in the last IPCC report, clouds have a major importance in the climate budget and need to be better characterized. Remote sensing observations are a way to obtain either global observations of cloud from satellites or a very fine description of clouds from airborne measurements. An increasing numbers of radiometers plan to measure polarized reflectances in addition to total reflectances, since this information is very helpful to obtain aerosol or cloud properties. In a near future, for example, the Multi-viewing, Multi-channel, Multi-polarization Imager (3MI) will be part the EPS-SG Eumetsat-ESA mission. It will achieve multi-angular polarimetric measurements from visible to shortwave infrared wavelengths. An airborne prototype, OSIRIS (Observing System Including Polarization in the Solar Infrared Spectrum), is also presently developed at the Laboratoire d'Optique Atmospherique and had already participated to several measurements campaigns. In order to analyze suitably the measured signal, it it necessary to have realistic and accurate models able to simulate polarized reflectances. The 3DCLOUD model (Szczap et al., 2014) was used to generate three-dimensional synthetic cloud and the 3D radiative transfer model, 3DMCPOL (Cornet et al., 2010) to compute realistic polarized reflectances. From these simulations, we investigate the effects of 3D cloud structures and heterogeneity on the polarized angular signature often used to retrieve cloud or aerosol properties. We show that 3D effects are weak for flat clouds but become quite significant for fractional clouds above ocean. The 3D effects are quite different according to the observation scale. For the airborne scale (few tens of meter), solar illumination effects can lead to polarized cloud reflectance values higher than the saturation limit predicted by the homogeneous cloud assumption. In the cloud gaps, corresponding to shadowed areas of the total reflectances, polarized signal can also be enhanced

  11. Radiation pressure calibration and test mass reflectivities for LISA Pathfinder

    International Nuclear Information System (INIS)

    Korsakova, Natalia; Kaune, Brigitte

    2017-01-01

    This paper describes a series of experiments which were carried out during the main operations of LISA Pathfinder. These experiments were performed by modulating the power of the measurement and reference beams. In one series of experiments the beams were sequentially switched on and off. In the other series of experiments the powers of the beams were modulated within 0.1% and 1% of the constant power. These experiments use recordings of the total power measured on the photodiodes to infer the properties of the Optical Metrology System (OMS), such as reflectivities of the test masses and change of the photodiode efficiencies with time. In the first case the powers are back propagated from the different photodiodes to the same place on the optical bench to express the unknown quantities in the measurement with the complimentary photodiode measurements. They are combined in the way that the only unknown left is the test mass reflectivities. The second experiment compared two estimates of the force applied to the test masses due to the radiation pressure that appears because of the beam modulations. One estimate of the force is inferred from the measurements of the powers on the photodiodes and propagation of this measurement to the test masses. The other estimation of the force is done by calculating it from the change in the main scientific output of the instrument – differential displacement of the two test masses. (paper)

  12. Radiation pressure calibration and test mass reflectivities for LISA Pathfinder

    Science.gov (United States)

    Korsakova, Natalia; Kaune, Brigitte; LPF Collaboration

    2017-05-01

    This paper describes a series of experiments which were carried out during the main operations of LISA Pathfinder. These experiments were performed by modulating the power of the measurement and reference beams. In one series of experiments the beams were sequentially switched on and off. In the other series of experiments the powers of the beams were modulated within 0.1% and 1% of the constant power. These experiments use recordings of the total power measured on the photodiodes to infer the properties of the Optical Metrology System (OMS), such as reflectivities of the test masses and change of the photodiode efficiencies with time. In the first case the powers are back propagated from the different photodiodes to the same place on the optical bench to express the unknown quantities in the measurement with the complimentary photodiode measurements. They are combined in the way that the only unknown left is the test mass reflectivities. The second experiment compared two estimates of the force applied to the test masses due to the radiation pressure that appears because of the beam modulations. One estimate of the force is inferred from the measurements of the powers on the photodiodes and propagation of this measurement to the test masses. The other estimation of the force is done by calculating it from the change in the main scientific output of the instrument - differential displacement of the two test masses.

  13. A new burmagomphid dragonfly from the Eocene of Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Julián F. Petrulevičius

    2017-11-01

    Full Text Available A new burmagomphid anisopteran, Satelitala soberana gen. et sp. nov. is described from the lower Eocene of Laguna del Hunco, Patagonia, Argentina. The new genus is characterised by hindwing characters such as the subdiscoidal triangle not elongated; anal loop divided longitudinally; paranal cell divided longitudinally; five terminal cells between RP and MA; five terminal cells between MP and CuA; and obtuse angle between PsA and CuP+AA. Burmagomphid dragonflies were represented so far only by one specimen from the middle Cretaceous of Southeast Asia. This new record extends the distribution to Patagonia, to the Cenozoic, and also to paleolake deposits.

  14. The third RAdiation transfer Model Intercomparison (RAMI) exercise: Documenting progress in canopy reflectance models

    NARCIS (Netherlands)

    Widlowski, J.L.; Taberner, M.; Pinty, B.; Bruniquel-Pinel, V.; Disney, M.I.; Fernandes, R.; Gastellu-Etchegorry, J.P.; Gobron, N.; Kuusk, A.; Lavergne, T.; LeBlanc, S.; Lewis, P.E.; Martin, E.; Mõttus, M.; North, P.R.J.; Qin, W.; Robustelli, M.; Rochdi, N.; Ruiloba, R.; Thompson, R.; Verhoef, W.; Verstraete, M.M.; Xie, D.

    2007-01-01

    [1] The Radiation Transfer Model Intercomparison ( RAMI) initiative benchmarks canopy reflectance models under well-controlled experimental conditions. Launched for the first time in 1999, this triennial community exercise encourages the systematic evaluation of canopy reflectance models on a

  15. Third Radiation Transfer Model Intercomparison (RAMI) exercise : Documenting progress in canopy reflectance models

    NARCIS (Netherlands)

    Widlowski, J.-L.; Taberner, M.; Pinty, B.; Bruniquel-Pinel, V.; Disney, M.; Fernandes, R.; Gastellu-Etchegorry, J.P.; Gobron, N.; Kuusk, A.; Lavergne, T.; Leblanc, S.; Lewis, P.E.; Martin, E.; Mottus, M.; North, P.R.J.; Qin, W.; Robustelli, M.; Rochdi, N.; Ruiloba, R.; Soler, C.; Thompson, R.; Verhoef, W.; Xie, D.; Thompson, R.

    2007-01-01

    The Radiation Transfer Model Intercomparison (RAMI) initiative benchmarks canopy reflectance models under well‐controlled experimental conditions. Launched for the first time in 1999, this triennial community exercise encourages the systematic evaluation of canopy reflectance models on a voluntary

  16. The Effect of Non-Lambertian Surface Reflectance on Aerosol Radiative Forcing

    Energy Technology Data Exchange (ETDEWEB)

    Ricchiazzi, P.; O' Hirok, W.; Gautier, C.

    2005-03-18

    Surface reflectance is an important factor in determining the strength of aerosol radiative forcing. Previous studies of radiative forcing assumed that the reflected surface radiance is isotropic and does not depend on incident illumination angle. This Lambertian reflection model is not a very good descriptor of reflectance from real land and ocean surfaces. In this study we present computational results for the seasonal average of short and long wave aerosol radiative forcing at the top of the atmosphere and at the surface. The effect of the Lambertian assumption is found through comparison with calculations using a more detailed bi-direction reflectance distribution function (BRDF).

  17. Validation Study of CODES Dragonfly Network Model with Theta Cray XC System

    Energy Technology Data Exchange (ETDEWEB)

    Mubarak, Misbah [Argonne National Lab. (ANL), Argonne, IL (United States); Ross, Robert B. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-05-31

    This technical report describes the experiments performed to validate the MPI performance measurements reported by the CODES dragonfly network simulation with the Theta Cray XC system at the Argonne Leadership Computing Facility (ALCF).

  18. A Method of Retrieving BRDF from Surface-Reflected Radiance Using Decoupling of Atmospheric Radiative Transfer and Surface Reflection

    Directory of Open Access Journals (Sweden)

    Alexander Radkevich

    2018-04-01

    Full Text Available Bi-directional reflection distribution function (BRDF defines anisotropy of the surface reflection. It is required to specify the boundary condition for radiative transfer (RT modeling used in aerosol retrievals, cloud retrievals, atmospheric modeling, and other applications. Ground based measurements of reflected radiance draw increasing attention as a source of information about anisotropy of surface reflection. Derivation of BRDF from surface radiance requires atmospheric correction. This study develops a new method of retrieving BRDF on its whole domain, making it immediately suitable for further atmospheric RT modeling applications. The method is based on the integral equation relating surface-reflected radiance, BRDF, and solutions of two auxiliary atmosphere-only RT problems. The method requires kernel-based BRDF. The weights of the kernels are obtained with a quickly converging iterative procedure. RT modeling has to be done only one time before the start of iterative process.

  19. Emerging dragonfly diversity at small Rhode Island (U.S.A.) wetlands along an urbanization gradient

    Science.gov (United States)

    Aliberti Lubertazzi, Maria A.; Ginsberg, Howard S.

    2010-01-01

    Natal habitat use by dragonflies was assessed on an urban to rural land-use gradient at a set of 21 wetlands, during two emergence seasons (2004, 2005). The wetlands were characterized for urbanization level by using the first factor from a principal components analysis combining chloride concentration in the wetland and percent forest in the surrounding buffer zone. Measurements of species diversity and its components (species richness and evenness) were analyzed and compared along the urbanization gradient, as were distributions of individual species. Dragonfly diversity, species richness, and evenness did not change along the urbanization gradient, so urban wetlands served as natal habitat for numerous dragonfly species. However, several individual species displayed strong relationships to the degree of urbanization, and most were more commonly found at urban sites and at sites with fish. In contrast, relatively rare species were generally found at the rural end of the gradient. These results suggest that urban wetlands can play important roles as dragonfly habitat and in dragonfly conservation efforts, but that conservation of rural wetlands is also important for some dragonfly species.

  20. Dragonfly: In Situ Exploration of Titan's Organic Chemistry and Habitability

    Science.gov (United States)

    Turtle, E. P.; Barnes, J. W.; Trainer, M. G.; Lorenz, R. D.

    2017-12-01

    Titan's abundant complex carbon-rich chemistry, interior ocean, and past presence of liquid water on the surface make it an ideal destination to study prebiotic chemical processes and document the habitability of an extraterrestrial environment. Titan exploration is a high science priority due to the level of organic synthesis that it supports. Moreover, opportunities for organics to have interacted with liquid water at the surface (e.g., in impact melt sheets) increase the potential for chemical processes to progress further, providing an unparalleled opportunity to investigate prebiotic chemistry, as well as to search for signatures of potential water-based or even hydrocarbon-based life. The diversity of Titan's surface materials and environments drives the scientific need to be able to sample a variety of locations, thus mobility is key for in situ measurements. Titan's atmosphere is 4 times denser than Earth's reducing the wing/rotor area required to generate a given amount of lift, and the low gravity reduces the required magnitude of lift, making heavier-than-air mobility highly efficient. Dragonfly is a rotorcraft lander mission proposed to NASA's New Frontiers Program to take advantage of Titan's unique natural laboratory to understand how far chemistry can progress in environments that provide key ingredients for life. Measuring the compositions of materials in different environments will reveal how far organic chemistry has progressed. Surface material can be sampled into a mass spectrometer to identify the chemical components available and processes at work to produce biologically relevant compounds. Bulk elemental surface composition can be determined by a neutron-activated gamma-ray spectrometer. Meteorology measurements can characterize Titan's atmosphere and diurnal and spatial variations therein. Geologic features can be characterized via remote-sensing observations, which also provide context for samples. Seismic sensing can probe subsurface

  1. Do dose area product meter measurements reflect radiation doses ...

    African Journals Online (AJOL)

    Enrique

    SA JOURNAL OF RADIOLOGY • August 2004. Abstract. This study determined the correlation between radiation doses absorbed by health care workers and dose area product meter (DAP) measurements at Universitas Hospital, Bloemfontein. The DAP is an instrument which accurately measures the radiation emitted from ...

  2. Do dose area product meter measurements reflect radiation doses ...

    African Journals Online (AJOL)

    This study determined the correlation between radiation doses absorbed by health care workers and dose area product meter (DAP) measurements at Universitas Hospital, Bloemfontein. The DAP is an instrument which accurately measures the radiation emitted from the source. The study included the interventional ...

  3. Reflection/suppression coatings for 900 - 1200 A radiation

    Science.gov (United States)

    Edelstein, Jerry

    1989-01-01

    The design and performance of multiple-layer, selective-reflection, selective-suppression coatings for the 900 - 1200 A band are described. These coatings are designed to optimize both high reflectivity at a desirable wavelength and low reflectivity at an undesirable wavelength. The minimum structure for a selective coating consists of a thin metal or metal oxide layer (50 - 150 A thickness) over an aluminum substrate protected with a semi-transparent dielectric (100 - 1000 A thickness). Predicted coating performance is strongly effected by varying the layer combination and thickness. A graphical method of optimizing the coating layer structure is developed. Aluminum, silicon, their oxides, and gold have been investigated as coating layer materials. A very simple coating with a 1026 to 1216 A reflectivity ratio greater than 100 was fabricated. Such reflection/suppression coatings may be of great utility to spaceborne EUV spectrographs.

  4. Fossil gaps inferred from phylogenies alter the apparent nature of diversification in dragonflies and their relatives

    Directory of Open Access Journals (Sweden)

    Nicholson David B

    2011-09-01

    Full Text Available Abstract Background The fossil record has suggested that clade growth may differ in marine and terrestrial taxa, supporting equilibrial models in the former and expansionist models in the latter. However, incomplete sampling may bias findings based on fossil data alone. To attempt to correct for such bias, we assemble phylogenetic supertrees on one of the oldest clades of insects, the Odonatoidea (dragonflies, damselflies and their extinct relatives, using MRP and MRC. We use the trees to determine when, and in what clades, changes in taxonomic richness have occurred. We then test whether equilibrial or expansionist models are supported by fossil data alone, and whether findings differ when phylogenetic information is used to infer gaps in the fossil record. Results There is broad agreement in family-level relationships between both supertrees, though with some uncertainty along the backbone of the tree regarding dragonflies (Anisoptera. "Anisozygoptera" are shown to be paraphyletic when fossil information is taken into account. In both trees, decreases in net diversification are associated with species-poor extant families (Neopetaliidae, Hemiphlebiidae, and an upshift is associated with Calopterygidae + Polythoridae. When ghost ranges are inferred from the fossil record, many families are shown to have much earlier origination dates. In a phylogenetic context, the number of family-level lineages is shown to be up to twice as high as the fossil record alone suggests through the Cretaceous and Cenozoic, and a logistic increase in richness is detected in contrast to an exponential increase indicated by fossils alone. Conclusions Our analysis supports the notion that taxa, which appear to have diversified exponentially using fossil data, may in fact have diversified more logistically. This in turn suggests that one of the major apparent differences between the marine and terrestrial fossil record may simply be an artifact of incomplete sampling

  5. Formulation comprising silicon microparticles, as a pigment that can absorb visible UV radiation and reflect ir radiation

    OpenAIRE

    Rodríguez, Marie-Isabelle; Fenollosa Esteve, Roberto; Meseguer, Francisco

    2011-01-01

    [EN] The invention relates to a formulation characterised in that it comprises silicon microparticles having a size between 0.010 um and 50 um in diameter, and to the use thereof as a pigment that can absorb visible UV radiation and reflect IR radiation.

  6. Nitrogen deficiency detection using reflected shortwave radiation from irrigated corn canopies

    International Nuclear Information System (INIS)

    Blackmer, T.M.; Schepers, J.S.; Varvel, G.E.; Walter-Shea, E.A.

    1996-01-01

    Techniques that measure the N status of corn (Zea mays L.) can aid in management decisions that have economic and environmental implications. This study was conducted to identify reflected electromagnetic wavelengths most sensitive to detecting N deficiencies in a corn canopy with the possibility for use as a management tool. Reflected shortwave radiation was measured from an irrigated corn N response trial with four hybrids and five N rates at 0, 40, 80, 120, and 160 kg N ha -1 in 1992 and 0, 50, 100, 150, and 200 kg N ha -1 in 1993. A portable spectroradiometer was used to measure reflected radiation (400-1100 nm in 1992, 350-1050 nm in 1993) from corn canopies at approximately the R5 growth stage. Regression analyses revealed that reflected radiation near 550 and 710 nm was superior to reflected radiation near 450 or 650 nm for detecting N deficiencies. The ratio of light reflectance between 550 and 600 nm to light reflectance between 800 and 900 nm also provided sensitive detection of N stress. In 1993, an inexpensive photometric cell, which has peak sensitivity to light centered at 550 nm, was also used to measure reflected radiation from a corn canopy. Photometric cell readings correlated with relative grain yield (P < 0.001, r 2 = 0.74), but more research will be required to develop procedures to account for varying daylight conditions. These results provide information needed for the development of variable-rate fertilizer N application technology. (author)

  7. The spatial distribution of infrared radiation from visible reflection nebulae

    Science.gov (United States)

    Luan, Ling; Werner, Michael W.; Dwek, Eli; Sellgren, Kris

    1989-01-01

    The emission at IRAS 12 and 25 micron bands of reflection nebulae is far in excess of that expected from the longer wavelength equilibrium thermal emission. The excess emission in the IRAS 12 micron band is a general phenomenon, seen in various components of interstellar medium such as IR cirrus clouds, H II regions, atomic and molecular clouds, and also normal spiral galaxies. This excess emission has been attributed to UV excited fluorescence in polycyclic aromatic hydrocarbon (PAH) molecules or to the effect of temperature fluctuations in very small grains. Results are presented of studies of IRAS data on reflection nebulae selected from the van den Bergh reflection nebulae sample. Detailed scans of flux ratio and color temperature across the nebulae were obtained in order to study the spatial distribution of IR emission. A model was used to predict the spatial distribution of IR emission from dust grains illuminated by a B type star. The model was also used to explore the excitation of the IRAS 12 micron band emission as a function of stellar temperature. The model predictions are in good agreement with the analysis of reflection nebulae, illuminated by stars with stellar temperature ranging from 21,000 down to 3,000 K.

  8. Perilesional edema in radiation necrosis reflects axonal degeneration

    International Nuclear Information System (INIS)

    Perez-Torres, Carlos J; Yuan, Liya; Schmidt, Robert E; Rich, Keith M; Ackerman, Joseph JH; Garbow, Joel R

    2015-01-01

    Recently, we characterized a Gamma Knife® radiation necrosis mouse model with various magnetic resonance imaging (MRI) protocols to identify biomarkers useful in differentiation from tumors. Though the irradiation was focal to one hemisphere, a contralateral injury was observed that appeared to be localized in the white matter only. Interestingly, this injury was identifiable in T2-weighted images, apparent diffusion coefficient (ADC), and magnetization transfer ratio (MTR) maps, but not on post-contrast T1-weighted images. This observation of edema independent of vascular changes is akin to the perilesional edema seen in clinical radiation necrosis. The pathology underlying the observed white-matter MRI changes was explored by performing immunohistochemistry for healthy axons and myelin. The presence of both healthy axons and myelin was reduced in the contralateral white-matter lesion. Based on our immunohistochemical findings, the contralateral white-matter injury is most likely due to axonal degeneration

  9. Dragonfly: Exploring Titan's Surface with a New Frontiers Relocatable Lander

    Science.gov (United States)

    Barnes, Jason W.; Turtle, Elizabeth P.; Trainer, Melissa G.; Lorenz, Ralph

    2017-10-01

    We proposed to the NASA New Frontiers 4 mission call a lander to assess Titan's prebiotic chemistry, evaluate its habitability, and search for biosignatures on its surface. Titan as an Ocean World is ideal for the study of prebiotic chemical processes and the habitability of an extraterrestrial environment due to its abundant complex carbon-rich chemistry and because both liquid water and liquid hydrocarbons can occur on its surface. Transient liquid water surface environments can be created by both impacts and cryovolcanic processes. In both cases, the water could mix with surface organics to form a primordial soup. The mission would sample both organic sediments and water ice to measure surface composition, achieving surface mobility by using rotors to take off, fly, and land at new sites. The Dragonfly rotorcraft lander can thus convey a single capable instrument suite to multiple locations providing the capability to explore diverse locations 10s to 100s of kilometers apart to characterize the habitability of Titan's environment, investigate how far prebiotic chemistry has progressed, and search for chemical signatures indicative of water- and/or hydrocarbon-based life.

  10. Evaluation of Topology-Aware Broadcast Algorithms for Dragonfly Networks

    Energy Technology Data Exchange (ETDEWEB)

    Dorier, Matthieu; Mubarak, Misbah; Ross, Rob; Li, Jianping Kelvin; Carothers, Christopher D.; Ma, Kwan-Liu

    2016-09-12

    Two-tiered direct network topologies such as Dragonflies have been proposed for future post-petascale and exascale machines, since they provide a high-radix, low-diameter, fast interconnection network. Such topologies call for redesigning MPI collective communication algorithms in order to attain the best performance. Yet as increasingly more applications share a machine, it is not clear how these topology-aware algorithms will react to interference with concurrent jobs accessing the same network. In this paper, we study three topology-aware broadcast algorithms, including one designed by ourselves. We evaluate their performance through event-driven simulation for small- and large-sized broadcasts (in terms of both data size and number of processes). We study the effect of different routing mechanisms on the topology-aware collective algorithms, as well as their sensitivity to network contention with other jobs. Our results show that while topology-aware algorithms dramatically reduce link utilization, their advantage in terms of latency is more limited.

  11. Some reflections on anthropology of the risk of radiation

    International Nuclear Information System (INIS)

    Van Nuffelen, D.

    1996-01-01

    Since any scientific result is, in the view of K. Popper, nothing else but a provisional truth, it is idle and unintelligent to claim than any given model is the best. It is true that some models are closer to reality than others, mainly because they are not sectarian, and as they are open to this reality which always partly escapes us, they reflect it better despite their implacable weaknesses. Man has to face the reality that involves radiological risk. The scientific study of man, anthropology, cannot confine it to a reductive and unilateral paradigm. Rather than taking the easy and wrong way by reducing man's part solely to the answers to an artificial questionnaire, social scientists have to question man's condition; and the human condition cannot be brought into scale. This paper examines these problems through the way various human groups define and treat the nuclear dangers. (author)

  12. INFLUENCE OF THE ORTHOGONALLY POLARIZED BACK REFLECTIONS ON THE POWER AND RADIATION SPECTRUM OF SUPERLUMINESCENT DIODES

    Directory of Open Access Journals (Sweden)

    A. B. Mukhtubayev

    2015-01-01

    Full Text Available We have investigated the back reflections influence on the spectrum for optical radiation source of superluminescent diode type and have provided optimal operating conditions of the radiation source. The feature of the research method is the usage of a fiber polarization controller and an optical mirror coated on the end of an optical fiber. The studies were conducted with two sources of optical radiation: ThorLabs superluminescent diode series S5FC1005SXL and LED module ELED-1550-1-E-9-SM1-FA-CW. It was revealed that at the value of back reflections equal to -13 dB relative to the output power source, a negative impact on power and spectral characteristics of the source with an optical power of 2.3 µW is beginning to appear. It was also confirmed that at the increase of the radiation power by increasing the source pumping current, back reflection influence is exhibiting at a lower level of back reflections. The results obtained need to be considered when designing fiber optic sensors in order to eliminate the effect of back reflections on the sources of optical radiation having been studied in this paper.

  13. Plasmonically Enhanced Reflectance of Heat Radiation from Low-Bandgap Semiconductor Microinclusions.

    Science.gov (United States)

    Tang, Janika; Thakore, Vaibhav; Ala-Nissila, Tapio

    2017-07-18

    Increased reflectance from the inclusion of highly scattering particles at low volume fractions in an insulating dielectric offers a promising way to reduce radiative thermal losses at high temperatures. Here, we investigate plasmonic resonance driven enhanced scattering from microinclusions of low-bandgap semiconductors (InP, Si, Ge, PbS, InAs and Te) in an insulating composite to tailor its infrared reflectance for minimizing thermal losses from radiative transfer. To this end, we compute the spectral properties of the microcomposites using Monte Carlo modeling and compare them with results from Fresnel equations. The role of particle size-dependent Mie scattering and absorption efficiencies, and, scattering anisotropy are studied to identify the optimal microinclusion size and material parameters for maximizing the reflectance of the thermal radiation. For composites with Si and Ge microinclusions we obtain reflectance efficiencies of 57-65% for the incident blackbody radiation from sources at temperatures in the range 400-1600 °C. Furthermore, we observe a broadbanding of the reflectance spectra from the plasmonic resonances due to charge carriers generated from defect states within the semiconductor bandgap. Our results thus open up the possibility of developing efficient high-temperature thermal insulators through use of the low-bandgap semiconductor microinclusions in insulating dielectrics.

  14. Dragonflies and Damselflies of Peninsular India-A Field Guide. E

    Indian Academy of Sciences (India)

    K A Subramaniam

    orange coloured segments at the base and end of the abdomen. Male: Eyes: Dark olivaceous ... K.A.Subramanian (2005) Dragonflies and Damselflies of Peninsular India-A Field Guide. E-Book of .... Usually perches on dry twigs near streams.

  15. Phasing of dragonfly wings can improve aerodynamic efficiency by removing swirl.

    Science.gov (United States)

    Usherwood, James R; Lehmann, Fritz-Olaf

    2008-11-06

    Dragonflies are dramatic, successful aerial predators, notable for their flight agility and endurance. Further, they are highly capable of low-speed, hovering and even backwards flight. While insects have repeatedly modified or reduced one pair of wings, or mechanically coupled their fore and hind wings, dragonflies and damselflies have maintained their distinctive, independently controllable, four-winged form for over 300Myr. Despite efforts at understanding the implications of flapping flight with two pairs of wings, previous studies have generally painted a rather disappointing picture: interaction between fore and hind wings reduces the lift compared with two pairs of wings operating in isolation. Here, we demonstrate with a mechanical model dragonfly that, despite presenting no advantage in terms of lift, flying with two pairs of wings can be highly effective at improving aerodynamic efficiency. This is achieved by recovering energy from the wake wasted as swirl in a manner analogous to coaxial contra-rotating helicopter rotors. With the appropriate fore-hind wing phasing, aerodynamic power requirements can be reduced up to 22 per cent compared with a single pair of wings, indicating one advantage of four-winged flying that may apply to both dragonflies and, in the future, biomimetic micro air vehicles.

  16. Radiative Transfer Equation for Anisotropic Spherical Medium with Specular Reflective Index

    International Nuclear Information System (INIS)

    Elghazaly, A.

    2009-01-01

    Radiative transfer problem for anisotropic scattering in a spherical homogeneous, turbid medium with diffuse and angular dependent (specular) reflecting boundaries is solved using the Pomraning-Eddington approximation method. The angular dependent specular reflectivity of the boundary is considered as Fresnel's reflection probability function. The partial heat flux is calculated with anisotropic scattering through a homogeneous solid sphere. The calculations are carried out for spherical media of radii 0.1, 1.0, and 10 mfp and for different scattering albedo. Two different weight functions are used to verify the boundary conditions. Our results are compared with the available data and give an excellent agreement for thick and highly scattering media

  17. Modelling terahertz radiation absorption and reflection with computational phantoms of skin and associated appendages

    Science.gov (United States)

    Vilagosh, Zoltan; Lajevardipour, Alireza; Wood, Andrew

    2018-01-01

    Finite-difference time-domain (FDTD) computational phantoms aid the analysis of THz radiation interaction with human skin. The presented computational phantoms have accurate anatomical layering and electromagnetic properties. A novel "large sheet" simulation technique is used allowing for a realistic representation of lateral absorption and reflection of in-vivo measurements. Simulations carried out to date have indicated that hair follicles act as THz propagation channels and confirms the possible role of melanin, both in nevi and skin pigmentation, to act as a significant absorber of THz radiation. A novel freezing technique has promise in increasing the depth of skin penetration of THz radiation to aid diagnostic imaging.

  18. Principles of the radiosity method versus radiative transfer for canopy reflectance modeling

    Science.gov (United States)

    Gerstl, Siegfried A. W.; Borel, Christoph C.

    1992-01-01

    The radiosity method is introduced to plant canopy reflectance modeling. We review the physics principles of the radiosity method which originates in thermal radiative transfer analyses when hot and cold surfaces are considered within a given enclosure. The radiosity equation, which is an energy balance equation for discrete surfaces, is described and contrasted with the radiative transfer equation, which is a volumetric energy balance equation. Comparing the strengths and weaknesses of the radiosity method and the radiative transfer method, we conclude that both methods are complementary to each other. Results of sample calculations are given for canopy models with up to 20,000 discrete leaves.

  19. Applying spaceborne reflectivity measurements for calculation of the solar ultraviolet radiation at ground level

    Directory of Open Access Journals (Sweden)

    P. N. den Outer

    2012-12-01

    Full Text Available Long-term analysis of cloud effects on ultraviolet (UV radiation on the ground using spaceborne observations requires the use of instruments that have operated consecutively. The longest data record can be built from the reflectivity measurements produced by the instruments Total Ozone Mapping Spectrometers (TOMS flown on Nimbus 7 from 1979 to 1992, TOMS on Earth Probe from 1996 to 2005, and the Ozone Monitoring Instrument (OMI flown on EOS Aura since 2004. The reflectivity data produced by TOMS on Earth Probe is only included until 2002. A comparison is made with cloud effects inferred from ground-based pyranometer measurements at over 83 World Radiation Data Centre stations. Modelled UV irradiances utilizing the standard reflectivity are compared with measurements of UV irradiances at eight European low-elevation stations. The reflectivity data of the two TOMS instruments shows a consistent agreement, and the required corrections are of low percentage, i.e. 2–3%. In contrast, the reflectivity product of OMI requires correction of 7–10%, and a solar angle dependency therein is more pronounced. These corrections were inferred from a comparison with pyranometer data, and tested using the UV measurements. The average reduction of UV radiation due to clouds for all sites together indicates a small trend: a diminishing cloudiness, in line with ground-based UV observations. Uncorrected implementation of the reflectivity data would have indicated the opposite.

    An optimal area was established for reflectivity data for the calculation of daily sums of UV radiation. It measures approximately 1.25° in latitudinal direction for square-shaped areas overhead the ground-based UV stations. Such an area can be traversed within 5 to 7 h at the average wind speeds found for the West European continent.

  20. Reflective ‘cool’ roofs under aerosol-burdened skies: radiative benefits across selected Indian cities

    International Nuclear Information System (INIS)

    Millstein, D E; Fischer, M L

    2014-01-01

    The use of reflective surfaces offers one low-cost solution for reducing solar loading to urban environments and the Earth that should be considered as part of sustainable urban design. Here, we characterize the radiative benefits, i.e. the additional shortwave radiation leaving the atmosphere, from the installation of highly reflective ‘cool’ roofs in urban areas in India that face relatively large local aerosol burdens. We use a previously tested column radiative transfer model to estimate the energy per unit area reflected to space from increasing the surface albedo at six cities within India. The model is used to characterize radiative transfer each day over five years (2008–2012) based on mid-day satellite retrievals of MODIS aerosol depth, cloud water path, and average surface albedo and MERRA atmospheric profiles of temperature and composition. Compared against ten months of field observations in two cities, the model derived incoming surface shortwave radiation estimates relative to observations show small biases (0.5% and −2.6%, at Pantnagar and Nainital, respectively). Despite the high levels of local aerosols we found cool roofs provided significant radiative benefits at all locations. Averaged over the five year period we found that increasing the albedo of 1 m 2 of roof area by 0.5 would reflect to space 0.9–1.2 kWh daily from 08:30–15:30 LST, depending on location. This is equivalent to a constant forcing of 37–50 W m −2 (equivalent to reducing CO 2 emissions by 74 to 101 kg CO 2 m −2 roof area). Last, we identify a co-benefit of improving air quality, in that removing aerosols from the atmosphere could increase the radiative benefits from cool roofs by 23–74%, with the largest potential increase found at Delhi and the smallest change found at Nainital. (letter)

  1. Application of Faraday rotator to suppression of target-reflected radiation in the optical path of a laser installation

    International Nuclear Information System (INIS)

    Bykovskiy, N.E.; Denus, S.; Dubik, A.; Ovsik, Y.; Lisunov, V.V.; Senatskiy, Y.V.; Fedotov, S.I.

    1988-01-01

    The interaction conditions between powerful laser radiation and a target are examined together with the Faraday rotators designed for suppressing target-reflected backward radiation in the neodymium glass laser optical path

  2. Invited Review Terahertz Transmission, Scattering, Reflection, and Absorption—the Interaction of THz Radiation with Soils

    Science.gov (United States)

    Lewis, R. A.

    2017-07-01

    Terahertz radiation has been proposed as a useful tool in the study of soils and related materials from such diverse perspectives as detection of non-metallic landmines to improving soil fertility by agricultural charcoals produced by pyrolysis of organic material. The main barrier to such applications is that soils are rather opaque at terahertz frequencies. In this article, the main findings to date on the interaction of terahertz radiation with soils are reviewed, organized around the four phenomena of terahertz: transmission, scattering, reflection, and absorption. Terahertz transmission through soils is generally low and decreases with frequency. Terahertz scattering is evident in many THz-soil interactions, as the wavelength of the radiation is of the order of the particle size. Terahertz reflection is important to communications as these develop from the GHz into the THz band. Terahertz absorption on diluted soil samples has been demonstrated to be effective in identifying soil constituents, such as aromatic compounds, and soil contaminants, such as pesticides.

  3. Effect of surface characteristics on diffuse reflection radiation at lambda=0. 40. mu. m

    Energy Technology Data Exchange (ETDEWEB)

    Takashima, T [Atmospheric Environment Service, Downsview, Ontario (Canada)

    1976-08-01

    The diffuse radiation in the upward direction at the top and at an internal level of an inhomogeneous atmosphere is computed at lambda=0.40 ..mu..m. The surface is assumed to reflect light in accordance with a hybrid mode of a diffuse and specular reflector. The objective is to estimate the effect of underlying surface characteristics in terms of the diffuse radiation field. By making use of these results, accuracy in monitoring the atmospheric aerosols would be increased for the use of remote sensing satellite techniques. Junge power law (..gamma..*=3) is adopted for the size distribution of aerosols (1963), while the data given by McClatchy et al. (1971) is used for the number density of aerosols with height distribution. It is noted from the computations that the diffuse reflection radiation is affected by the surface characteristics, even if the albedo of the surface is a fixed constant and very small.

  4. How difficult is it to reintroduce a dragonfly? Fifteen years monitoring Leucorrhinia dubia at the receiving site

    Czech Academy of Sciences Publication Activity Database

    Dolný, A.; Šigutová, H.; Ožana, S.; Choleva, Lukáš

    2018-01-01

    Roč. 218, č. 3 (2018), s. 110-117 ISSN 0006-3207 Institutional support: RVO:67985904 Keywords : conservation translocation * dragonfly reintroduction * odonata Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.022, year: 2016

  5. Very small beam-size measurement by a reflective synchrotron radiation interferometer

    Directory of Open Access Journals (Sweden)

    T. Naito

    2006-12-01

    Full Text Available A synchrotron radiation (SR interferometer with Herschelian reflective optics has been developed for the measurement of beams of several μm in size. In a conventional refractive SR interferometer, the dispersion effect of the objective lens limits the instrument to a smaller range of beam-size measurements. To avoid this problem, we designed a Herschelian arrangement of reflective optics for the interferometer. The effectiveness of the reflective SR interferometer was confirmed at the KEK Accelerator Test Facility (ATF damping ring. The measured vertical beam size obtained using the reflective SR interferometer was 4.7   μm and the estimated vertical emittance was 0.97×10^{-11}   m.

  6. Winter radiation extinction and reflection in a boreal pine canopy: measurements and modelling

    International Nuclear Information System (INIS)

    Pomeroy, J.W.; Dion, K.

    1996-01-01

    Predicting the rate of snow melt and intercepted snow sublimation in boreal forests requires an understanding of the effects of snow-covered conifers on the exchange of radiant energy. This study examined the amount of intercepted snow on a jack pine canopy in the boreal forest of central Saskatchewan and the shortwave and net radiation exchange with this canopy, to determine the effect of intercepted snow and canopy structure on shortwave radiation reflection and extinction and net radiation attenuation in a boreal forest. The study focused on clear sky conditions, which are common during winter in the continental boreal forest. Intercepted snow was found to have no influence on the clear-sky albedo of the canopy, the extinction of short wave radiation by the canopy or ratio of net radiation at the canopy top to that at the surface snow cover. Because of the low albedo of the snow-covered canopy, net radiation at the canopy top remains positive and a large potential source of energy for sublimation. The canopy albedo declines somewhat as the extinction efficiency of the underlying canopy increases. The extinction efficiency of short wave radiation in the canopy depends on solar angle because of the approximately horizontal orientation of pine branches. For low solar angles above the horizon, the extinction efficiency is quite low and short wave transmissivity through the canopy is relatively high. As the solar angle increases, extinction increases up to angles of about 50°, and then declines. Extinction of short wave radiation in the canopy strongly influences the attenuation of net radiation by the canopy. Short wave radiation that is extinguished by branches is radiated as long wave, partly downwards to the snow cover. The ratio of net radiation at the canopy top to that at the snow cover surface increases with the extinction of short wave radiation and is negative for low extinction efficiencies. For the pine canopy examined, the daily mean net radiation at

  7. Winter Radiation Extinction and Reflection in a Boreal Pine Canopy: Measurements and Modelling

    Science.gov (United States)

    Pomeroy, J. W.; Dion, K.

    1996-12-01

    Predicting the rate of snowmelt and intercepted snow sublimation in boreal forests requires an understanding of the effects of snow-covered conifers on the exchange of radiant energy. This study examined the amount of intercepted snow on a jack pine canopy in the boreal forest of central Saskatchewan and the shortwave and net radiation exchange with this canopy, to determine the effect of intercepted snow and canopy structure on shortwave radiation reflection and extinction and net radiation attenuation in a boreal forest. The study focused on clear sky conditions, which are common during winter in the continental boreal forest. Intercepted snow was found to have no influence on the clear-sky albedo of the canopy, the extinction of short wave radiation by the canopy or ratio of net radiation at the canopy top to that at the surface snow cover. Because of the low albedo of the snow-covered canopy, net radiation at the canopy top remains positive and a large potential source of energy for sublimation. The canopy albedo declines somewhat as the extinction efficiency of the underlying canopy increases. The extinction efficiency of short wave radiation in the canopy depends on solar angle because of the approximately horizontal orientation of pine branches. For low solar angles above the horizon, the extinction efficiency is quite low and short wave transmissivity through the canopy is relatively high. As the solar angle increases, extinction increases up to angles of about 50̂, and then declines. Extinction of short wave radiation in the canopy strongly influences the attenuation of net radiation by the canopy. Short wave radiation that is extinguished by branches is radiated as long wave, partly downwards to the snow cover. The ratio of net radiation at the canopy top to that at the snow cover surface increases with the extinction of short wave radiation and is negative for low extinction efficiencies. For the pine canopy examined, the daily mean net radiation at the

  8. Reflections

    Directory of Open Access Journals (Sweden)

    Joanne Embree

    2001-01-01

    Full Text Available Ideally, editorials are written one to two months before publication in the Journal. It was my turn to write this one. I had planned to write the first draft the evening after my clinic on Tuesday, September 11. It didn't get done that night or during the next week. Somehow, the topic that I had originally chosen just didn't seem that important anymore as I, along my friends and colleagues, reflected on the changes that the events of that day were likely to have on our lives.

  9. PN solutions of radiative heat transfer in a slab with reflective boundaries

    International Nuclear Information System (INIS)

    Atalay, M.A.

    2006-01-01

    The spherical harmonics method is used to obtain solution for the radiative heat transfer equation for a slab with reflective boundaries. An absorbing, emitting, non-isothermal, gray medium is considered with linearly anisotropic scattering. Under the condition of the thermal equilibrium, the slab boundaries are subjected to specular and diffuse reflection. The analytical form of solutions is obtained for both conservative and non-conservative cases. The accuracy of the method was verified by benchmark comparisons against the solutions of an earlier work performed by the normal-mode expansion technique. The present predictions of heat flux were found to be in good agreement with the benchmark data. a

  10. Reflection of electromagnetic radiation from plasma with an anisotropic electron velocity distribution

    International Nuclear Information System (INIS)

    Vagin, K. Yu.; Uryupin, S. A.

    2013-01-01

    The reflection of a test electromagnetic pulse from the plasma formed as a result of tunnel ionization of atoms in the field of a circularly polarized high-power radiation pulse is analyzed using the kinetic approach to describe electron motion. It is shown that the reflected pulse is significantly amplified due to the development of Weibel instability. The amplification efficiency is determined by the maximum value of the instability growth rate, which depends on the degree of anisotropy of the photoelectron distribution function

  11. Radiation reflection from a semi-infinite layer of magnetized plasma

    International Nuclear Information System (INIS)

    Silant'ev, N.A.

    1981-01-01

    From a transpot equation and the invariance principle, the expre-- ssion is derived for the density matrix of the reflected radiation from a semi-infinite layer of magnetized plasma. The albedo of the medium is expressed in terms of the tensor H-functions. The numerical solutions are given for the Stokes parameters of the radiation for the case when the magnetic field is perpendicular to the surface. It is shown that the presence of the magnetic field may significantly decrease the albedo [ru

  12. Spectral composition of shortwave radiation reflected and deep penetrating into snow near the Barentsburg settlement (Svalbard

    Directory of Open Access Journals (Sweden)

    P. N. Svyashchennikov

    2015-01-01

    Full Text Available Data on spectral composition of shortwave radiation that is reflected from snow and penetrates deep into the snow cover obtained near the Barentsburg settlement (Svalbard are discussed in the paper. Measurements were made by the use of the spectral radiometer TriOS Ramses within the wavelength range of 280–950 nm. The results will allow more proper taking account of the anthropogenic pollution effects on the radiative properties of snow cover under conditions of industrial activity related to the coal extraction and burning in Barentsburg.

  13. Synchrotron radiation total reflection X-ray fluorescence (SR-TXRF) for evaluation of food contamination

    International Nuclear Information System (INIS)

    Vives, A.E.S.; Brienza, S.M.B.; Moreira, S.; Zucchi, O.L.A.; Nascimento Filho, V.F.

    2006-01-01

    The objective of this study was to use synchrotron radiation total reflection X-ray fluorescence analysis (SR-TXRF) for the determination of metals and other elements in food available to the population in commercial establishments, in order to evaluate the risks of contamination by these products. The analyzed species were vegetables, leafy vegetables, fruits, cereal and grain. The results indicated that some species were contaminated by Cr, Cu, Zn and Pb with concentrations much higher than the reference values. (author)

  14. Total reflection X-ray fluorescence analysis with synchrotron radiation monochromatized by multilayer structures

    International Nuclear Information System (INIS)

    Rieder, R.; Wobrauschek, P.; Ladisich, W.; Streli, C.; Aiginger, H.; Garbe, S.; Gaul, G.; Knoechel, A.; Lechtenberg, F.

    1995-01-01

    To achieve lowest detection limits in total reflection X-ray fluorescence analysis (TXRF) synchrotron radiation has been monochromatized by a multilayer structure to obtain a relative broad energy band compared to Bragg single crystals for an efficient excitation. The energy has been set to 14 keV, 17.5 keV, 31 keV and about 55 keV. Detection limits of 20 fg and 150 fg have been achieved for Sr and Cd, respectively. ((orig.))

  15. Deformation behavior of dragonfly-inspired nodus structured wing in gliding flight through experimental visualization approach.

    Science.gov (United States)

    Zhang, Sheng; Sunami, Yuta; Hashimoto, Hiromu

    2018-04-10

    Dragonfly has excellent flight performance and maneuverability due to the complex vein structure of wing. In this research, nodus as an important structural element of the dragonfly wing is investigated through an experimental visualization approach. Three vein structures were fabricated as, open-nodus structure, closed-nodus structure (with a flex-limiter) and rigid wing. The samples were conducted in a wind tunnel with a high speed camera to visualize the deformation of wing structure in order to study the function of nodus structured wing in gliding flight. According to the experimental results, nodus has a great influence on the flexibility of the wing structure. Moreover, the closed-nodus wing (with a flex-limiter) enables the vein structure to be flexible without losing the strength and rigidity of the joint. These findings enhance the knowledge of insect-inspired nodus structured wing and facilitate the application of Micro Air Vehicle (MAV) in gliding flight.

  16. The effects of global change on the distribution, species richness and life history of European dragonflies

    DEFF Research Database (Denmark)

    Olsen, Kent

    2016-01-01

    traits such as taxonomy, habitat specificity, metabolic plasticity, and biogeographic traits such zoogeographical origin. In Paper I we describe how changes in species richness pattern across Europe correlate with range changes in different taxonomic and biogeographic groups of dragonflies. We found...... specialized species adapted to permanent running (perennial lotic) water habitats. We found that species reproducing in temporary water track climate changes better than species adapted to permanent water. In Paper III we explore the relationship between metabolic plasticity (expressed as the ability to shift...... with less metabolic plasticity. We conducted experimental ex-situ measurements of metabolic rates measured as respiration rates at 10°C and 20°C, respectively, of four Scandinavian dragonfly species. We used two species with a northern distribution, one with a southern distribution and one ubiquitous...

  17. Andromorphic female of the dragonfly Neurothemis tullia tullia (Drury (Odonata: Libellulidae, central India

    Directory of Open Access Journals (Sweden)

    R.J. Andrew

    2013-01-01

    Full Text Available Neurothemis tullia tullia (Drury is a common dragonfly which occurs in large colonies in swamps and heavily- weeded tanks in different parts of India. It exhibits striking sexual dimorphism in colour and wing spot patterns. The male is dark with a large blue-black spot on the wing base while the female is dull olivaceous and the wing base is amber yellow. The sexes can be easily identified from quite a far distance. Andromorphic females are very rarely found in anisopteran dragonflies. This paper describes and compares not only the coloration and wing spots of the normal male and female with this andromorphic female but also reports about its sexual fitness to produce viable eggs.

  18. Phylogeographic Analysis Elucidates the Influence of the Ice Ages on the Disjunct Distribution of Relict Dragonflies in Asia

    Science.gov (United States)

    Büsse, Sebastian; von Grumbkow, Philipp; Hummel, Susanne; Shah, Deep Narayan; Tachamo Shah, Ram Devi; Li, Jingke; Zhang, Xueping; Yoshizawa, Kazunori; Wedmann, Sonja; Hörnschemeyer, Thomas

    2012-01-01

    Unusual biogeographic patterns of closely related groups reflect events in the past, and molecular analyses can help to elucidate these events. While ample research on the origin of disjunct distributions of different organism groups in the Western Paleartic has been conducted, such studies are rare for Eastern Palearctic organisms. In this paper we present a phylogeographic analysis of the disjunct distribution pattern of the extant species of the strongly cool-adapted Epiophlebia dragonflies from Asia. We investigated sequences of the usually more conserved 18 S rDNA and 28 S rDNA genes and the more variable sequences of ITS1, ITS2 and CO2 of all three currently recognised Epiophlebia species and of a sample of other odonatan species. In all genes investigated the degrees of similarity between species of Epiophlebia are very high and resemble those otherwise found between different populations of the same species in Odonata. This indicates that substantial gene transfer between these populations occurred in the comparatively recent past. Our analyses imply a wide distribution of the ancestor of extant Epiophlebia in Southeast Asia during the last ice age, when suitable habitats were more common. During the following warming phase, its range contracted, resulting in the current disjunct distribution. Given the strong sensitivity of these species to climatic parameters, the current trend to increasing global temperatures will further reduce acceptable habitats and seriously threaten the existences of these last representatives of an ancient group of Odonata. PMID:22666462

  19. Fundamental rights reflected by the legislation regarding radiation and nuclear power

    International Nuclear Information System (INIS)

    Han, Eun Ok; Lee, Jae Seong; Cho, Hong Jea

    2016-01-01

    Despite the visible growth in radiation usage and nuclear power development, the analysis of their relationship with fundamental rights, a subject of public concern regarding issues including the right to health, environmental rights, safety rights, the right to know, the right to development, and the right to life, is currently non-existent. 15-29By examining various fundamental rights in the context of positive laws regarding radiation and nuclear power in an idealistic perspective that guarantees the maximum degree of rights, this paper aims to propose legislative supplements that will lead to improvements in quality of life. In the South Korean Constitution, radiation and nuclear power is a subject incorporating several rights, including at least 12 clauses that are directly related to fundamental rights; these constitutional rights are manifested in the various clauses of the 14 positive laws regarding radiation and nuclear power. The question on the relative importance of each fundamental right as reflected in these positive laws- whether the right to life should be prioritized or considered equal in weight to the right to health, environmental rights, the right to know, and safety rights- requires careful deliberation and is difficult to humanly resolve in the short term. Making policy that expands the usage of radiation and nuclear power while simultaneously preventing their associated risks is an important task for the Republic of Korea, and a proper value judgment is necessary to find a balance in its associated rights

  20. Fundamental rights reflected by the legislation regarding radiation and nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Ok [Korea Academy of Nuclear Safety, Seoul (Korea, Republic of); Lee, Jae Seong [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Cho, Hong Jea [Korea National Defense University, Goyang (Korea, Republic of)

    2016-05-15

    Despite the visible growth in radiation usage and nuclear power development, the analysis of their relationship with fundamental rights, a subject of public concern regarding issues including the right to health, environmental rights, safety rights, the right to know, the right to development, and the right to life, is currently non-existent. 15-29By examining various fundamental rights in the context of positive laws regarding radiation and nuclear power in an idealistic perspective that guarantees the maximum degree of rights, this paper aims to propose legislative supplements that will lead to improvements in quality of life. In the South Korean Constitution, radiation and nuclear power is a subject incorporating several rights, including at least 12 clauses that are directly related to fundamental rights; these constitutional rights are manifested in the various clauses of the 14 positive laws regarding radiation and nuclear power. The question on the relative importance of each fundamental right as reflected in these positive laws- whether the right to life should be prioritized or considered equal in weight to the right to health, environmental rights, the right to know, and safety rights- requires careful deliberation and is difficult to humanly resolve in the short term. Making policy that expands the usage of radiation and nuclear power while simultaneously preventing their associated risks is an important task for the Republic of Korea, and a proper value judgment is necessary to find a balance in its associated rights.

  1. Properties of spectra of the reflected and transmitted radiation during propagation of relativistically strong laser pulses in underdense plasmas

    International Nuclear Information System (INIS)

    Bulanov, S.V.; Esirkepov, T.Z.; Naumova, N.M.

    1996-01-01

    Particle-in-cell simulation has been performed to study the spatial-temporal evolution of the pulse propagating in an underdense plasma. The spectra both of the reflected and transmitted radiation are investigated. The spectrum structure of the reflected radiation is due to the backward stimulated Raman scattering meanwhile the transmitted radiation structure is mainly due to the nonlinear self-phase-modulation. The influence of the pulse shape on the transmitted radiation spectrum is revealed. The dependence of the main features of the spectrum and the self-consistent pulse distortion is found. The pulse distortion is accompanied by the relativistic electrons generation. copyright 1996 American Institute of Physics

  2. Soil moisture estimation using reflected solar and emitted thermal infrared radiation

    Science.gov (United States)

    Jackson, R. D.; Cihlar, J.; Estes, J. E.; Heilman, J. L.; Kahle, A.; Kanemasu, E. T.; Millard, J.; Price, J. C.; Wiegand, C. L.

    1978-01-01

    Classical methods of measuring soil moisture such as gravimetric sampling and the use of neutron moisture probes are useful for cases where a point measurement is sufficient to approximate the water content of a small surrounding area. However, there is an increasing need for rapid and repetitive estimations of soil moisture over large areas. Remote sensing techniques potentially have the capability of meeting this need. The use of reflected-solar and emitted thermal-infrared radiation, measured remotely, to estimate soil moisture is examined.

  3. Fast solar radiation pressure modelling with ray tracing and multiple reflections

    Science.gov (United States)

    Li, Zhen; Ziebart, Marek; Bhattarai, Santosh; Harrison, David; Grey, Stuart

    2018-05-01

    Physics based SRP (Solar Radiation Pressure) models using ray tracing methods are powerful tools when modelling the forces on complex real world space vehicles. Currently high resolution (1 mm) ray tracing with secondary intersections is done on high performance computers at UCL (University College London). This study introduces the BVH (Bounding Volume Hierarchy) into the ray tracing approach for physics based SRP modelling and makes it possible to run high resolution analysis on personal computers. The ray tracer is both general and efficient enough to cope with the complex shape of satellites and multiple reflections (three or more, with no upper limit). In this study, the traditional ray tracing technique is introduced in the first place and then the BVH is integrated into the ray tracing. Four aspects of the ray tracer were tested for investigating the performance including runtime, accuracy, the effects of multiple reflections and the effects of pixel array resolution.Test results in runtime on GPS IIR and Galileo IOV (In Orbit Validation) satellites show that the BVH can make the force model computation 30-50 times faster. The ray tracer has an absolute accuracy of several nanonewtons by comparing the test results for spheres and planes with the analytical computations. The multiple reflection effects are investigated both in the intersection number and acceleration on GPS IIR, Galileo IOV and Sentinel-1 spacecraft. Considering the number of intersections, the 3rd reflection can capture 99.12 %, 99.14 % , and 91.34 % of the total reflections for GPS IIR, Galileo IOV satellite bus and the Sentinel-1 spacecraft respectively. In terms of the multiple reflection effects on the acceleration, the secondary reflection effect for Galileo IOV satellite and Sentinel-1 can reach 0.2 nm /s2 and 0.4 nm /s2 respectively. The error percentage in the accelerations magnitude results show that the 3rd reflection should be considered in order to make it less than 0.035 % . The

  4. Radiation protection actions at Swedish nuclear power plants 1994-2002 and some reflections about the near future

    International Nuclear Information System (INIS)

    Erixon, Stig; Godaas, Tommy; Hofvander, Peter; Lund, Ingmar; Malmqvist, Lars; Thimgren, Ingela; Oelander-Guer, Hanna

    2003-12-01

    This report provides a summary of radiation protection experiences over the years 1994-2002 in the Swedish nuclear power industry. Actions to reduce radiation levels in reactor systems, occupational exposure results and some reflections about the near future are presented

  5. [A Method to Reconstruct Surface Reflectance Spectrum from Multispectral Image Based on Canopy Radiation Transfer Model].

    Science.gov (United States)

    Zhao, Yong-guang; Ma, Ling-ling; Li, Chuan-rong; Zhu, Xiao-hua; Tang, Ling-li

    2015-07-01

    Due to the lack of enough spectral bands for multi-spectral sensor, it is difficult to reconstruct surface retlectance spectrum from finite spectral information acquired by multi-spectral instrument. Here, taking into full account of the heterogeneity of pixel from remote sensing image, a method is proposed to simulate hyperspectral data from multispectral data based on canopy radiation transfer model. This method first assumes the mixed pixels contain two types of land cover, i.e., vegetation and soil. The sensitive parameters of Soil-Leaf-Canopy (SLC) model and a soil ratio factor were retrieved from multi-spectral data based on Look-Up Table (LUT) technology. Then, by combined with a soil ratio factor, all the parameters were input into the SLC model to simulate the surface reflectance spectrum from 400 to 2 400 nm. Taking Landsat Enhanced Thematic Mapper Plus (ETM+) image as reference image, the surface reflectance spectrum was simulated. The simulated reflectance spectrum revealed different feature information of different surface types. To test the performance of this method, the simulated reflectance spectrum was convolved with the Landsat ETM + spectral response curves and Moderate Resolution Imaging Spectrometer (MODIS) spectral response curves to obtain the simulated Landsat ETM+ and MODIS image. Finally, the simulated Landsat ETM+ and MODIS images were compared with the observed Landsat ETM+ and MODIS images. The results generally showed high correction coefficients (Landsat: 0.90-0.99, MODIS: 0.74-0.85) between most simulated bands and observed bands and indicated that the simulated reflectance spectrum was well simulated and reliable.

  6. Specular reflection treatment for the 3D radiative transfer equation solved with the discrete ordinates method

    Energy Technology Data Exchange (ETDEWEB)

    Le Hardy, D. [Université de Nantes, LTN UMR CNRS 6607 (France); Favennec, Y., E-mail: yann.favennec@univ-nantes.fr [Université de Nantes, LTN UMR CNRS 6607 (France); Rousseau, B. [Université de Nantes, LTN UMR CNRS 6607 (France); Hecht, F. [Sorbonne Universités, UPMC Université Paris 06, UMR 7598, inria de Paris, Laboratoire Jacques-Louis Lions, F-75005, Paris (France)

    2017-04-01

    The contribution of this paper relies in the development of numerical algorithms for the mathematical treatment of specular reflection on borders when dealing with the numerical solution of radiative transfer problems. The radiative transfer equation being integro-differential, the discrete ordinates method allows to write down a set of semi-discrete equations in which weights are to be calculated. The calculation of these weights is well known to be based on either a quadrature or on angular discretization, making the use of such method straightforward for the state equation. Also, the diffuse contribution of reflection on borders is usually well taken into account. However, the calculation of accurate partition ratio coefficients is much more tricky for the specular condition applied on arbitrary geometrical borders. This paper presents algorithms that calculate analytically partition ratio coefficients needed in numerical treatments. The developed algorithms, combined with a decentered finite element scheme, are validated with the help of comparisons with analytical solutions before being applied on complex geometries.

  7. Reflections on the juridical implications of the medical use of radiations and radioisotope

    International Nuclear Information System (INIS)

    Campos, Ana Celia P.P.; Cuperschmid, Ethel Mizrahy; Campos, Tarcisio P. Ribeiro de

    2007-01-01

    The pacific use of radiation and radioisotopes for the society presents radiological risks, due its capacity to produce damage to environmental and human being, contrasting with its high economic and social benefits. In the face of the risk, juridical system leans over to reach the required regulations that implies in the balance between human and environmental security and the expected improvements of the medical nuclear techniques. The Brazilian Constitution of 1988 tries to provide the normalization for the application of the nuclear energy and its radioisotopes. However, target as a strategically technology and due to its expansion, its regulations still deserves analyses and reflections. The present paper starts from the Constitution presenting the references about the theme and analyzing it. It is addressed the principle of the objective civil responsibility making analyses on the use of radiations and radioisotope on the medicine. It addresses the role of federal autonomy related to the 'MCT - Ministerio de Ciencia e Tecnologia' with its accumulative functions in society, such as scientific and technologic development, education, and its own focalization. The recent opening of the monopoly for the production of radioisotopes for very short half-lives is also discussed. It makes a comparison between juridical aspects of Brazil with international system. The present article contributes to open same topics of discussions on the Brazilian juridical aspects involving radiations and radioisotopes application on medicine. (author)

  8. Reflections on the juridical implications of the medical use of radiations and radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Ana Celia P.P. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Direito]. E-mails: anaceu2000@yahoo.com.br; Cuperschmid, Ethel Mizrahy [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Centro de Memoria da Medicina - CEMMOR]. E-mail: ethel.mizrahy@yahoo.com; Campos, Tarcisio P. Ribeiro de [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares]. E-mail: campos@nuclear.ufmg.br

    2007-07-01

    The pacific use of radiation and radioisotopes for the society presents radiological risks, due its capacity to produce damage to environmental and human being, contrasting with its high economic and social benefits. In the face of the risk, juridical system leans over to reach the required regulations that implies in the balance between human and environmental security and the expected improvements of the medical nuclear techniques. The Brazilian Constitution of 1988 tries to provide the normalization for the application of the nuclear energy and its radioisotopes. However, target as a strategically technology and due to its expansion, its regulations still deserves analyses and reflections. The present paper starts from the Constitution presenting the references about the theme and analyzing it. It is addressed the principle of the objective civil responsibility making analyses on the use of radiations and radioisotope on the medicine. It addresses the role of federal autonomy related to the 'MCT - Ministerio de Ciencia e Tecnologia' with its accumulative functions in society, such as scientific and technologic development, education, and its own focalization. The recent opening of the monopoly for the production of radioisotopes for very short half-lives is also discussed. It makes a comparison between juridical aspects of Brazil with international system. The present article contributes to open same topics of discussions on the Brazilian juridical aspects involving radiations and radioisotopes application on medicine. (author)

  9. Effectiveness of birds, butterflies, dragonflies, damselflies and invertebrates as indicators of freshwater ecological integrity

    Science.gov (United States)

    Chama, Lackson; Siachoono, Stanford

    2015-04-01

    Human activities such as mining and agriculture are among the major threats to biodiversity globally. Discharges from these activities have been shown to negatively affect ecological processes, leading to ecosystem degradation and species loss across biomes. Freshwater systems have been shown to be particularly vulnerable, as discharges tend to spread rapidly here than in other ecosystems. Hence, there is need to routinely monitor the quality of these systems if impacts of discharges from human activities are to be minimised. Besides the use of conventional laboratory techniques, several studies have recently shown that organisms such as birds, butterflies, dragonflies, damselflies and invertebrates are also good indicators of ecological integrity and should therefore be used as alternatives to monitoring the quality of various ecosystems. However, most of these studies have only studied one or two of these organisms against ecosystem health, and it remains unclear whether all of them respond similarly to changes in different drivers of environmental change. We investigated the response of the diversity of birds, butterflies, dragonflies, damselflies and invertebrates to changing water quality along the Kafue River in Zambia. Sampling was done at 13 different sampling points stretching over a distance of 60Km along the river. At each point, both the diversity of each organism and the water quality were assessed. Water quality was determined by testing its temperature, pH, redox, electrical conductivity, turbidity and copper parameters. We then tested how the diversity of each organism responded to changes in these water parameters. All water parameters varied significantly across sampling points. The diversity of birds and damselflies remained unaffected by any of the water parameters used. However, the diversity of butterflies reduced with increasing pH, turbidity and copper, albeit it remained unaffected by other water parameters. The diversity of dragonflies

  10. Effects of a dragonfly (Anax i.) homeopathic remedy on learning, memory and cell morphology in mice.

    Science.gov (United States)

    Mutlu, Oguz; Ulak, Guner; Kokturk, Sibel; Komsuoglu Celikyurt, Ipek; Tanyeri, Pelin; Akar, Furuzan; Erden, Faruk

    2016-02-01

    Homeopathy is a form of alternative medicine in which uses highly diluted preparations that are believed to cause healthy people to exhibit symptoms similar to those exhibited by patients. The aim of this study was to investigate the effects of dragonfly (Anax imperator, Anax i.) on learning and memory in naive mice using the Morris water maze (MWM) test; moreover, the effects of dragonfly on MK-801-induced cognitive dysfunction were evaluated. Male balb-c mice were treated with dragonfly (30C and 200C) or MK-801 (0.2 mg/kg) alone or concurrently (n = 10). Dragonfly (D) and MK-801 were administered subchronically for 6 days intraperitoneally 60 min and 30 min, respectively, before the daily performance of the MWM test. This study revealed that in the familiarization session and first session of the MWM test, Anax i. D30 significantly decreased escape latency compared to the control group, although MK-801, D30 and D200 significantly increased escape latency at the end of five acquisition sessions. Anax i. combined with dizocilpine maleate (MK-801) also significantly decreased escape latency in the familiarization session and first session of the MWM test, although this combination increased escape latency compared to the MK-801 alone group at the end of the test. Time spent in escape platform's quadrant in the probe trial significantly decreased while mean distance to platform significantly increased in MK-801, D30 and D200 groups. In the MWM test, Anax i. combined with MK-801 significantly decreased speed of the animals compared to the MK-801 alone group. General cell morphology was disturbed in the MK-801 group while D30 and D200 seemed to improve cell damage in the MK-801 group. These results suggest that the homeopathic Anax i. can impair learning acquisition and reference memory, and it has beneficial effects on disturbed cell morphology. Copyright © 2015 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  11. New Eocene damselflies and first Cenozoic damsel-dragonfly of the isophlebiopteran lineage (Insecta: Odonata).

    Science.gov (United States)

    Garrouste, Romain; Nel, André

    2015-10-09

    The study of a new specimen of Petrolestes hendersoni from the Eocene Green Formation allows a more precise description of the enigmatic damselfly and the diagnosis of the Petrolestini. Petrolestes messelensis sp. nov. is described from the Eocene Messel Formation in Germany, extending the distribution of the Petrolestini to the European Eocene. The new damsel-dragonfly family Pseudostenolestidae is described for the new genus and species Pseudostenolestes bechlyi, from the Eocene Messel Formation. It is the first Cenozoic representative of the Mesozoic clade Isophlebioptera.

  12. Total and available metal contents in sediments by synchrotron radiation total reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Moreira, Silvana; Sobrinho, Gilmar A.; Jesus, Edgar F.O. de; Lopes, Ricardo T.

    2002-01-01

    In this work the total and available contents of Al, Si, Cl, K, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, Ba, Ce and Pb in sediments from river Atibaia were determined by Synchrotron Radiation Total Reflection X-Ray Fluorescence technique. The detection limits for K series varies from 200 ng.mL -1 for Al to 2 ng.mL -1 for Zn while for L series the value varies from 20 ng.mL -1 for Ba to 10 ng.mL -1 for Pb. The samples were submitted to two different processes, in order to obtain the total and biological available metal contents. The information about metal content is a important parameter for a correct evaluation about the hydrologic cycle in Piracicaba basin. All the measure were carried out at the National Synchrotron Light Laboratory, Campinas, SP, Brazil, using a white beam for excitation. (author)

  13. Multielemental analysis in Brazilian cigarettes using total reflection X-ray fluorescence with synchrotron radiation

    International Nuclear Information System (INIS)

    Serpa, Renata F.B.; Jesus, Edgar F.O. de; Lopes, Ricardo T.; Moreira, Silvana

    2005-01-01

    In order to identify major and trace elements in conventional and light Brazilian cigarettes, Total Reflection X-Ray Fluorescence with Synchrotron Radiation (SR-TXRF) was used. The fluorescence measurements were carried out at Brazilian Synchrotron Light Laboratory, Campinas - Sao Paulo. This technique enables detection limit is in the ngg -1 range, which is very useful in elemental tobacco smoke analysis, since it presents most of its elements at a trace level. The major elements identified in tobacco samples were: S, Cl, K, Ca, Mn, Fe and Cd, and the trace elements were: Ti, Cr, Ni, Cu, Zn, Br, Rb, Sr and Ba. However in tobacco smoke samples, there were only two major elements: K and Ca, the others were present a trace level. The rate transfer of tobacco to tobacco smoke was about 2.5 % for all elements studied. (author)

  14. Beer analysis by synchrotron radiation total reflection X-ray fluorescence (SR-TXRF)

    International Nuclear Information System (INIS)

    Moreira, Silvana; Vives, Ana Elisa S. de; Nascimento Filho, Virgilio F.; Zucchi, Orgheda L.D.A.

    2005-01-01

    In this work the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn and Br in twenty-nine brands of national and international beers were determined by Synchrotron Radiation Total Reflection X-Ray Fluorescence analysis (SR-TXRF). The results were compared with the limits established by the Brazilian Legislation and the nutritive values established by National Agricultural Library (NAL). The measurements were performed at the X-ray Fluorescence Beamline at Synchrotron Light Source Laboratory, in Campinas, Sao Paulo, Brazil, using a polychromatic beam for excitation. A small volume of 5 μL of sample beers containing just an internal standard, used to correct geometry effects, were analyzed without any pre-treatment. The measuring time was 100 s and the detection limits obtained varied from 1μg.L -1 for Mn and Fe to 15μg.L -1 for P. (author)

  15. Beer analysis by synchrotron radiation total reflection X-ray fluorescence (SR-TXRF)

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo. Dept. de Recursos Hidricos]. E-mail: silvana@fec.unicamp.br; Vives, Ana Elisa S. de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Nascimento Filho, Virgilio F. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Instrumentacao Nuclear]. E-mail: virgilio@cena.usp.br; Zucchi, Orgheda L.D.A. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas de Ribeirao Preto]. E-mail: olzucchi@fcfrp.usp.br

    2005-07-01

    In this work the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn and Br in twenty-nine brands of national and international beers were determined by Synchrotron Radiation Total Reflection X-Ray Fluorescence analysis (SR-TXRF). The results were compared with the limits established by the Brazilian Legislation and the nutritive values established by National Agricultural Library (NAL). The measurements were performed at the X-ray Fluorescence Beamline at Synchrotron Light Source Laboratory, in Campinas, Sao Paulo, Brazil, using a polychromatic beam for excitation. A small volume of 5 {mu}L of sample beers containing just an internal standard, used to correct geometry effects, were analyzed without any pre-treatment. The measuring time was 100 s and the detection limits obtained varied from 1{mu}g.L{sup -1} for Mn and Fe to 15{mu}g.L{sup -1} for P. (author)

  16. ICRP 2015. International symposium on the radiation protection system. Report and reflection on a significant symposium

    International Nuclear Information System (INIS)

    Lorenz, Bernd

    2016-01-01

    The ICRP international symposium on the radiation protection system provides always extensive information on new developments in radiation protection. The ICRP 2105 discussed the following issues: radiation effects of low dose irradiation, dose coefficients for internal and external exposures, radiation protection in nuclear medicine, application of ICRP recommendations, environmental protection, studies on existing exposure situations, medical radiation protection today, science behind radiation doses, new developments in radiation effects, and ethics in radiation protection.

  17. Unusual reflection of electromagnetic radiation from a stack of graphene layers at oblique incidence

    International Nuclear Information System (INIS)

    Bludov, Yu V; Peres, N M R; Vasilevskiy, M I

    2013-01-01

    We study the interaction of electromagnetic (EM) radiation with single-layer graphene and a stack of parallel graphene sheets at arbitrary angles of incidence. It is found that the behavior is qualitatively different for transverse magnetic (or p-polarized) and transverse electric (or s-polarized) waves. In particular, the absorbance of single-layer graphene attains a minimum (maximum) for the p (s)-polarization at the angle of total internal reflection when the light comes from a medium with a higher dielectric constant. In the case of equal dielectric constants of the media above and beneath graphene, for grazing incidence graphene is almost 100% transparent to p-polarized waves and acts as a tunable mirror for the s-polarization. These effects are enhanced for a stack of graphene sheets, so the system can work as a broad band polarizer. It is shown further that a periodic stack of graphene layers has the properties of a one-dimensional photonic crystal, with gaps (or stop bands) at certain frequencies. When an incident EM wave is reflected from this photonic crystal, the tunability of the graphene conductivity renders the possibility of controlling the gaps, and the structure can operate as a tunable spectral-selective mirror. (paper)

  18. Synchrotron radiation total reflection x-ray fluorescence analysis; of polymer coated silicon wafers

    International Nuclear Information System (INIS)

    Brehm, L.; Kregsamer, P.; Pianetta, P.

    2000-01-01

    It is well known that total reflection x-ray fluorescence (TXRF) provides an efficient method for analyzing trace metal contamination on silicon wafer surfaces. New polymeric materials used as interlayer dielectrics in microprocessors are applied to the surface of silicon wafers by a spin-coating process. Analysis of these polymer coated wafers present a new challenge for TXRF analysis. Polymer solutions are typically analyzed for bulk metal contamination prior to application on the wafer using inductively coupled plasma mass spectrometry (ICP-MS). Questions have arisen about how to relate results of surface contamination analysis (TXRF) of a polymer coated wafer to bulk trace analysis (ICP-MS) of the polymer solutions. Experiments were done to explore this issue using synchrotron radiation (SR) TXRF. Polymer solutions were spiked with several different concentrations of metals. These solutions were applied to silicon wafers using the normal spin-coating process. The polymer coated wafers were then measured using the SR-TXRF instrument set-up at the Stanford Synchrotron Radiation Laboratory (SSRL). Several methods of quantitation were evaluated. The best results were obtained by developing calibration curves (intensity versus ppb) using the spiked polymer coated wafers as standards. Conversion of SR-TXRF surface analysis results (atoms/cm 2 ) to a volume related concentration was also investigated. (author)

  19. Viability of long range dragonfly migration across the Indian Ocean: An energetics perspective

    Science.gov (United States)

    Saha, Sandeep; Nirwal, Satvik

    2016-11-01

    Recently Pantala flavescens (dragonflies) have been reported to migrate in millions from India to Eastern Africa on a multigenerational migratory circuit of length 14000-18000 kms. We attempt to understand the ability of dragonflies to perform long range migration by examining the energetics using computer simulations. In absence of a theory for long range insect migrations, we resort to the extensive literature on long range bird migration from the energetics perspective. The flight energetics depends upon instantaneous power and velocity. The mechanical flight power is computed from the power curve which is then converted to mass depletion using Brequet's equation. However, the mechanical flight power itself depends upon the instantaneous velocity which can vary depending upon the current mass. In order to predict the range in our simulations, we assume that the insect progressively tries to achieve the maximum range velocity. The results indicate that the migration range is approximately 1260 kms in 70 hours based on the true airspeed. However, our analysis is restricted by the lack of data and certain caveats in drag prediction and basal metabolism rate.

  20. Flow around a corrugated wing over the range of dragonfly flight

    Science.gov (United States)

    Padinjattayil, Sooraj; Agrawal, Amit

    2017-11-01

    The dragonfly flight is very much affected by the corrugations on their wings. A PIV based study is conducted on a rigid corrugated wing for a range of Reynolds number 300-12000 and three different angles of attack (5°-15°) to understand the mechanism of dragonfly flight better. The study revealed that the shape of the corrugation plays a key role in generating vortices. The vortices trapped in the valleys of corrugation dictates the shape of a virtual airfoil around the corrugated wing. A fluid roller bearing effect is created over the virtual airfoil when the trapped vortices merge with each other. A travelling wave produced by the moving virtual boundary around the fluid roller bearings avoids the formation of boundary layer on the virtual surface, thereby leading to high aerodynamic performance. It is found that the lift coefficient increases as the number of vortices increases on the suction surface. Also, it is shown that the partially merged co- rotating vortices give higher lift as compared to fully merged vortices. Further, the virtual airfoil formed around the corrugated wing is compared with a superhydrophobic airfoil which exhibits slip on its surface; several similarities in their flow characteristics are observed. The corrugated airfoil performs superior to the superhydrophobic airfoil in the aerodynamic efficiency due to the virtual slip caused by the travelling wave.

  1. Biogeographic evaluation of the dragonflies and damselflies in the Eastern Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Fontana-Bria, L.

    2017-03-01

    Full Text Available Insects are one of the most diverse groups of animals in terrestrial ecosystems, and are thus a good model system to study macrogeographic patterns in species’ distributions. Here we perform a biogeographical analysis of the dragonflies and damselflies in the Valencian Country (Eastern Iberian Peninsula. We also compare the species present in this territory with those in the adjacent territories of Catalonia and Aragon, and with those present in the whole Iberian Peninsula. Furthermore, we update the list of species of dragonflies and damselflies in the Valencian territory (65 species, and discuss the current status of two of them: Macromia splendens and Lindenia tetraphylla. Our results highlight that the Valencian Country has a higher proportion of Ethiopian elements but a lower proportion of Eurosiberian elements than Catalonia and Aragon. We also emphasize the importance of volunteer work in providing new knowledge on this group of iconic insects, and the relevance of museum collections in preserving them. The role of climate change in the distribution of Odonata is also discussed.

  2. Analysis of Selected Photovoltaic Panels Operating Parameters as a Function of Partial Shading and Intensity of Reflected Radiation

    Directory of Open Access Journals (Sweden)

    Bilčík Matúš

    2018-03-01

    Full Text Available Due to expansion of utilisation of photovoltaics in ordinary households, the question arises how this phenomenon affects the electric power of photovoltaic modules. The article deals with the electric power analysis of photovoltaic modules as a function of two very important factors. The first examined factor was partial shading, and the second factor was the intensity of reflected radiation. In order to determine the dependence of module power on the aforementioned parameters, a measurement system under laboratory conditions has been prepared. For identification of the reflected radiation effect on the power of the photovoltaic module, a series of measurements was performed on 7 different surfaces with the same radiation source. It is evident from obtained experimental result that the ratio of reflected irradiation on the solar module power is 1.29%. By simulation of partial shading of photovoltaic module, the decrease of 86.15% in its output power was identified.

  3. A novel insect defensin mediates the inducible antibacterial activity in larvae of the dragonfly Aeschna cyanea (Paleoptera, Odonata)

    NARCIS (Netherlands)

    Bulet, P.; Cociancich, S.; Reuland, M.; Sauber, F.; Bischoff, Rainer; Hegy, G.; Van Dorsselaer, A.; Hetru, C.; Hoffmann, J.A.

    1992-01-01

    The injection of low doses of bacteria into the aquatic larvae of dragonflies (Aeschna cyanea, Odonata, Paleoptera) induces the appearance in their hemolymph of a potent antibacterial activity. We have isolated a 38-residue peptide from this hemolymph which is strongly active against Gram-positive

  4. Definition of datum of materials lump size on conveyors by means of reflected gamma-radiation method

    International Nuclear Information System (INIS)

    Gal'yanov, A.V.; Antonov, V.A.; Laptev, Yu.V.

    2001-01-01

    A method of technological control of large-size lumps in conveyor-transported crushed material based on intensity measurement of X-ray and gamma radiation reflected from the material surface was suggested. The method was substantiated theoretically and as a result it was shown that dispersion of radiation intensity, multiply measured for short periods of time, can be analytic parameter of large-size lumps yield. Principled methodical and design recommendations on the method practical applications are given [ru

  5. Dependence of laser radiation intensity on the elastic deformation of a revolving optical disk with a reflective coating

    Science.gov (United States)

    Gladyshev, V. O.; Portnov, D. I.

    2016-12-01

    The physical mechanism of alteration of intensity of linearly polarized monochromatic electromagnetic radiation with λ = 630 nm in a revolving dielectric disk with a mirror coating is examined. The effect is induced by elastic deformation due to the revolution and by thermoelastic deformation of the optically transparent disk. These deformations result in birefringence, the polarization plane rotation, and a 30-40% change in the intensity of reflected radiation.

  6. Synchrotron Radiation Total Reflection X-ray Fluorescence Spectroscopy for Microcontamination Analysis on Silicon Wafer Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Takaura, Norikatsu

    1997-10-01

    As dimensions in state-of-the-art CMOS devices shrink to less than 0.1 pm, even low levels of impurities on wafer surfaces can cause device degradation. Conventionally, metal contamination on wafer surfaces is measured using Total Reflection X-Ray Fluorescence Spectroscopy (TXRF). However, commercially available TXRF systems do not have the necessary sensitivity for measuring the lower levels of contamination required to develop new CMOS technologies. In an attempt to improve the sensitivity of TXRF, this research investigates Synchrotron Radiation TXRF (SR TXRF). The advantages of SR TXRF over conventional TXRF are higher incident photon flux, energy tunability, and linear polarization. We made use of these advantages to develop an optimized SR TXRF system at the Stanford Synchrotron Radiation Laboratory (SSRL). The results of measurements show that the Minimum Detection Limits (MDLs) of SR TXRF for 3-d transition metals are typically at a level-of 3x10{sup 8} atoms/cm{sup 2}, which is better than conventional TXRF by about a factor of 20. However, to use our SR TXRF system for practical applications, it was necessary to modify a commercially available Si (Li) detector which generates parasitic fluorescence signals. With the modified detector, we could achieve true MDLs of 3x10{sup 8} atoms/cm{sup 2} for 3-d transition metals. In addition, the analysis of Al on Si wafers is described. Al analysis is difficult because strong Si signals overlap the Al signals. In this work, the Si signals are greatly reduced by tuning the incident beam energy below the Si K edge. The results of our measurements show that the sensitivity for Al is limited by x-ray Raman scattering. Furthermore, we show the results of theoretical modeling of SR TXRF backgrounds consisting of the bremsstrahlung generated by photoelectrons, Compton scattering, and Raman scattering. To model these backgrounds, we extended conventional theoretical models by taking into account several aspects particular

  7. Optical Observations of Psr J2021+3651 in the Dragonfly Nebula With the GTC

    Science.gov (United States)

    Kirichenko, Aida; Danilenko, Andrey; Shternin, Peter; Shibanov, Yuriy; Ryspaeva, Elizaveta; Zyuzin, Dima; Durant, Martin; Kargaltsev, Oleg; Pavlov, George; Cabrera-Lavers, Antonio

    2015-03-01

    PSR J2021+3651 is a 17 kyr old rotation powered pulsar detected in the radio, X-rays, and γ-rays. It powers a torus-like pulsar wind nebula with jets, dubbed the Dragonfly, which is very similar to that of the Vela pulsar. The Dragonfly is likely associated with the extended TeV source VER J2019+368 and extended radio emission. We conducted first deep optical observations with the Gran Telescopio Canarias in the Sloan r‧ band to search for optical counterparts of the pulsar and its nebula. No counterparts were detected down to r‧ ≳ 27.2 and ≳24.8 for the point-like pulsar and the compact X-ray nebula, respectively. We also reanalyzed Chandra archival X-ray data taking into account an interstellar extinction-distance relation, constructed by us for the Dragonfly line of sight using the red-clump stars as standard candles. This allowed us to constrain the distance to the pulsar, D=1.8-1.4+1.7 kpc at 90% confidence. It is much smaller than the dispersion measure distance of ˜12 kpc but compatible with a γ-ray “pseudo-distance” of 1 kpc. Based on that and the optical upper limits, we conclude that PSR J2021+3651, similar to the Vela pulsar, is a very inefficient nonthermal emitter in the optical and X-rays, while its γ-ray efficiency is consistent with an average efficiency for γ-pulsars of similar age. Our optical flux upper limit for the pulsar is consistent with the long-wavelength extrapolation of its X-ray spectrum while the nebula flux upper limit does not constrain the respective extrapolation. Based on observations made with the Gran Telescopio Canarias (GTC), instaled in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofsica de Canarias, in the island of La Palma, programme GTC3-11B.

  8. Parameter study of simplified dragonfly airfoil geometry at Reynolds number of 6000.

    Science.gov (United States)

    Levy, David-Elie; Seifert, Avraham

    2010-10-21

    Aerodynamic study of a simplified Dragonfly airfoil in gliding flight at Reynolds numbers below 10,000 is motivated by both pure scientific interest and technological applications. At these Reynolds numbers, the natural insect flight could provide inspiration for technology development of Micro UAV's and more. Insect wings are typically characterized by corrugated airfoils. The present study follows a fundamental flow physics study (Levy and Seifert, 2009), that revealed the importance of flow separation from the first corrugation, the roll-up of the separated shear layer to discrete vortices and their role in promoting flow reattachment to the aft arc, as the leading mechanism enabling high-lift, low drag performance of the Dragonfly gliding flight. This paper describes the effect of systematic airfoil geometry variations on the aerodynamic properties of a simplified Dragonfly airfoil at Reynolds number of 6000. The parameter study includes a detailed analysis of small variations of the nominal geometry, such as corrugation placement or height, rear arc and trailing edge shape. Numerical simulations using the 2D laminar Navier-Stokes equations revealed that the flow accelerating over the first corrugation slope is followed by an unsteady pressure recovery, combined with vortex shedding. The latter allows the reattachment of the flow over the rear arc. Also, the drag values are directly linked to the vortices' magnitude. This parametric study shows that geometric variations which reduce the vortices' amplitude, as reduction of the rear cavity depth or the reduction of the rear arc and trailing edge curvature, will reduce the drag values. Other changes will extend the flow reattachment over the rear arc for a larger mean lift coefficients range; such as the negative deflection of the forward flat plate. These changes consequently reduce the drag values at higher mean lift coefficients. The detailed geometry study enabled the definition of a corrugated airfoil

  9. The multispectral reflectance of shortwave radiation by agricultural crops in relation with their morphological and optical properties

    NARCIS (Netherlands)

    Bunnik, N.J.J.

    1978-01-01

    Relations between morphological properties of uniform canopies. optical properties of the leaves and reflection of shortwave radiation, in the visible light region and the near infrared, by crops are the subject of this thesis.

    The aim of the study was a further investigation of

  10. Ground-Based Observations and Modeling of the Visibility and Radar Reflectivity in a Radiation Fog Layer

    NARCIS (Netherlands)

    Boers, R.; Baltink, K.H.; Hemink, H.J.; Bosveld, F.C.; Moerman, M.

    2013-01-01

    The development of a radiation fog layer at the Cabauw Experimental Site for Atmospheric Research(51.97°N, 4.93°E) on 23 March 2011 was observed with ground-based in situ and remote sensing observationsto investigate the relationship between visibility and radar reflectivity. The fog layer thickness

  11. Antithermal shield for rockets with heat evacuation by infrared radiation reflection

    Directory of Open Access Journals (Sweden)

    Ioan RUSU

    2010-12-01

    Full Text Available At high speed, the friction between the air mass and the rocket surface causes a localheating of over 1000 Celsius degrees. For the heat protection of the rocket, on its outside surfacethermal shields are installed.Studying the Coanda effect, the fluid flow on solids surface, respectively, the author Ioan Rusuhas discovered by simply researches that the Coanda effect could be /extended also to the fluid flowon discontinuous solids, namely, on solids provided with orifices. This phenomenon was named by theauthor, the expanded Coanda effect. Starting with this discovery, the author has invented a thermalshield, registered at The State Office for inventions and Trademarks OSIM, deposit F 2010 0153This thermal shield:- is built as a covering rocket sheet with many orifices installed with a minimum space fromthe rocket body- takes over the heat fluid generated by the frontal part of the rocket and avoids the directcontact between the heat fluid and the rocket body- ensures the evacuation of the infrared radiation, generated by the heat fluid flowing overthe shield because of the extended Coanda effect by reflection from the rocket bodysurface.

  12. Earth Reflected Solar Radiation Incident upon an Arbitrarily Oriented Spinning Flat Plate

    Science.gov (United States)

    Cunningham, Fred G.

    1963-01-01

    A general derivation is given for the earth reflected solar radiation input to a flat plate--a solar cell paddle, for example--which is spinning about an axis coincident with the axis of symmetry of the satellite to which it is affixed. The resulting equations are written for the general case so that arbitrary orientations of the spin axis with respect to the earth-satellite line and arbitrary orientations of the normal to the plate with respect to the spin axis can be treated. No attempt is made to perform the resulting integrations because of the complexity of the equations; nor is there any attempt to delineate the integration limits for the general case. However, the equations governing these limits are given. The appendixes contain: the results, in graphical form, of two representative examples; the general computer program for the calculation is given in Fortran notation; and the results of a calculation of the distribution of albedo energy on the proposed Echo II satellite. The value of the mean solar constant used is 1.395 times 10 (sup 4) ergs per centimeters-squared per second; the mean albedo of the earth is assumed to be 0.34; and the earth is assumed to be a diffuse reflector.

  13. Multielemental analysis in cigarettes using total reflection X-ray fluorescence with synchrotron radiation

    International Nuclear Information System (INIS)

    Barbosa, R.F.; Anjos, M.J. dos; Jesus, E.F.O. de; Lopes, R.T.; Moreira, S.

    2008-01-01

    Full text: It is well known that trace elements have important ejects in the life processes. Some of these elements are toxic for the human even at a very low level of intake. It is known that tobacco plant easily absorbs the heavy metals from the soil, especially Cd and Ni, accumulating them in its leaves. Part of these metals are transferred from tobacco to human body where they will be accumulated and damage some organs, mainly kidneys and liver. In this way, cigarettes are responsible for the death of millions of people in the world, about one death every eight seconds. The aim of this work was to determine the elemental concentrations of ten different elements in tobacco of Brazilian cigarettes used Total Reflection X-Ray Fluorescence with Synchrotron Radiation method. The fluorescence measurements were carried out at Brazilian Synchrotron Light Laboratory, Campinas - Sao Paulo. A qualitative analysis of spectral peaks showed that the samples contained potassium, calcium, titanium, chromium, manganese, iron, copper, rubidium and strontium. Among these elements, calcium, potassium and iron presented the highest concentrations. There was a wide range in the elemental concentrations in the tobacco, due various factors, such as agricultural practices, soil characteristics, climatic conditions and plant varieties. Our results are in good concern with the results reported by the scientific literature

  14. Vortex interactions between forewing and hindwing of dragonfly in hovering flight

    Directory of Open Access Journals (Sweden)

    Chun-Mei Xie

    2015-01-01

    Full Text Available Two tandem flapping wings in viscous flow were modeled by using the immersed boundary method for exploration of the aerodynamics of dragonfly in hovering flight. Interaction between the forewing and the hindwing, and its effect on the lift forces, were examined by varying the phase difference of the wing motions and the inter-distance of the two wings. Two vortex interaction modes were identified at different phase differences and inter-distances, which give rise to significant variations of the lift forces. The first interaction mode increases the lift of the forewing and the second one enhances the lift of the hindwing. The two modes occur at different time during a flapping period and have different influence on the lift of wings as the phase difference varies.

  15. Dragonfly (insecta: odonata) diversity in two use of soils in a tropical dry forest

    International Nuclear Information System (INIS)

    Altamiranda S, Mariano

    2009-01-01

    Dragonfly diversity was estimated in the Agricultural Center Cotove (Santafe de Antioquia-Colombia). Active capture using an entomological net was used. Each transect was located perpendicular to the water body, for a length of approximately 200 m and a lateral extension of 8 m. Twenty Odonata species were registered, from 5 families and 15 genus. Libellulidae showed the biggest abundance and richness, with 65 specimens that represent 53.7% of the total abundance, and 12 species that represent 60% of the registered community. The diversity was high in the forest in reference at crop; however, the low abundances register highlight the need for greater sampling effort in cultivating, for a better estimate of ? diversity; the diversity was of 12 species and the complementary index was of 0.6, it indicates that the Odonata's fauna is characteristic and distinctive for each use of soil.

  16. Odonata (dragonflies and damselflies) as a bridge between ecology and evolutionary genomics.

    Science.gov (United States)

    Bybee, Seth; Córdoba-Aguilar, Alex; Duryea, M Catherine; Futahashi, Ryo; Hansson, Bengt; Lorenzo-Carballa, M Olalla; Schilder, Ruud; Stoks, Robby; Suvorov, Anton; Svensson, Erik I; Swaegers, Janne; Takahashi, Yuma; Watts, Phillip C; Wellenreuther, Maren

    2016-01-01

    Odonata (dragonflies and damselflies) present an unparalleled insect model to integrate evolutionary genomics with ecology for the study of insect evolution. Key features of Odonata include their ancient phylogenetic position, extensive phenotypic and ecological diversity, several unique evolutionary innovations, ease of study in the wild and usefulness as bioindicators for freshwater ecosystems worldwide. In this review, we synthesize studies on the evolution, ecology and physiology of odonates, highlighting those areas where the integration of ecology with genomics would yield significant insights into the evolutionary processes that would not be gained easily by working on other animal groups. We argue that the unique features of this group combined with their complex life cycle, flight behaviour, diversity in ecological niches and their sensitivity to anthropogenic change make odonates a promising and fruitful taxon for genomics focused research. Future areas of research that deserve increased attention are also briefly outlined.

  17. Project Dragonfly: A feasibility study of interstellar travel using laser-powered light sail propulsion

    Science.gov (United States)

    Perakis, Nikolaos; Schrenk, Lukas E.; Gutsmiedl, Johannes; Koop, Artur; Losekamm, Martin J.

    2016-12-01

    Light sail-based propulsion systems are a candidate technology for interplanetary and interstellar missions due to their flexibility and the fact that no fuel has to be carried along. In 2014, the Initiative for Interstellar Studies (i4is) hosted the Project Dragonfly Design Competition, which aimed at assessing the feasibility of sending an interstellar probe propelled by a laser-powered light sail to another star system. We analyzed and designed a mission to the Alpha Centauri system, with the objective to carry out science operations at the destination. Based on a comprehensive evaluation of currently available technologies and possible locations, we selected a lunar architecture for the laser system. It combines the advantages of surface- and space-based systems, as it requires no station keeping and suffers no atmospheric losses. We chose a graphene-based sandwich material for the light sail because of its low density. Deceleration of the spacecraft sufficient for science operations at the target system is achieved using both magnetic and electric sails. Applying these assumptions in a simulation leads to the conclusion that 250 kg of scientific payload can be sent to Alpha Centauri within the Project Dragonfly Design Competition's constraints of 100 year travel duration and 100 GW laser beam power. This is only sufficient to fulfill parts of the identified scientific objectives, and therefore renders the usefulness of such a mission questionable. A better sail material or higher laser power would improve the acceleration behavior, an increase in the mission time would allow for larger spacecraft masses.

  18. On an integral equation arising in the transport of radiation through a slab involving internal reflection

    International Nuclear Information System (INIS)

    Williams, M.M.R.

    2005-01-01

    The integral equation derived by Nieuwenhuizen and Luck for transmission of radiation through an optically thick diffusive medium is reconsidered in the light of radiative transfer theory and extended to slabs of arbitrary thickness. (author)

  19. Renal shear wave velocity by acoustic radiation force impulse did not reflect advanced renal impairment.

    Science.gov (United States)

    Takata, Tomoaki; Koda, Masahiko; Sugihara, Takaaki; Sugihara, Shinobu; Okamoto, Toshiaki; Miyoshi, Kenichi; Matono, Tomomitsu; Hosho, Keiko; Mae, Yukari; Iyama, Takuji; Fukui, Takeaki; Fukuda, Satoko; Munemura, Chishio; Isomoto, Hajime

    2016-12-01

    Acoustic radiation force impulse is a noninvasive method for evaluating tissue elasticity on ultrasound. Renal shear wave velocity measured by this technique has not been fully investigated in patients with renal disease. The aim of the present study was to compare renal shear wave velocity in end-stage renal disease patients and that in patients without chronic kidney disease and to investigate influencing factors. Renal shear wave velocities were measured in 59 healthy young subjects (control group), 31 subjects without chronic kidney disease (non-CKD group), and 39 end-stage renal disease patients (ESRD group). Each measurement was performed 10 times at both kidneys, and the mean value of eight of 10 measurements, excluding the maximum and minimum values, was compared. Renal shear wave velocity could be measured in all subjects. Renal shear wave velocity in the control group was higher than in the non-CKD group and in the ESRD group, and no difference was found between the non-CKD group and the ESRD group. Age and depth were negatively correlated to the renal shear wave velocity. In multiple regression analysis, age and depth were independent factors for renal shear wave velocity, while renal impairment was not. There was no difference between the non-CKD group and the ESRD group, even when ages were matched and depth was adjusted. Renal shear wave velocity was not associated with advanced renal impairment. However, it reflected alteration of renal aging, and this technique may be useful to detect renal impairment in the earlier stages. © 2015 Asian Pacific Society of Nephrology.

  20. Ray Guns and Radium: Radiation in the Public Imagination as Reflected in Early American Science Fiction

    Science.gov (United States)

    Slaughter, Aimee

    2014-01-01

    The 1920s and 1930s were a period which saw great popular interest in radiation and radioactivity in America, and the establishment of a new genre of pulp literature, science fiction. Radiation was prevalent in American popular culture at the time, and sf stories were dependent upon radiation for much of their color and excitement. In this case…

  1. Spectral Kernel Approach to Study Radiative Response of Climate Variables and Interannual Variability of Reflected Solar Spectrum

    Science.gov (United States)

    Jin, Zhonghai; Wielicki, Bruce A.; Loukachine, Constantin; Charlock, Thomas P.; Young, David; Noeel, Stefan

    2011-01-01

    The radiative kernel approach provides a simple way to separate the radiative response to different climate parameters and to decompose the feedback into radiative and climate response components. Using CERES/MODIS/Geostationary data, we calculated and analyzed the solar spectral reflectance kernels for various climate parameters on zonal, regional, and global spatial scales. The kernel linearity is tested. Errors in the kernel due to nonlinearity can vary strongly depending on climate parameter, wavelength, surface, and solar elevation; they are large in some absorption bands for some parameters but are negligible in most conditions. The spectral kernels are used to calculate the radiative responses to different climate parameter changes in different latitudes. The results show that the radiative response in high latitudes is sensitive to the coverage of snow and sea ice. The radiative response in low latitudes is contributed mainly by cloud property changes, especially cloud fraction and optical depth. The large cloud height effect is confined to absorption bands, while the cloud particle size effect is found mainly in the near infrared. The kernel approach, which is based on calculations using CERES retrievals, is then tested by direct comparison with spectral measurements from Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) (a different instrument on a different spacecraft). The monthly mean interannual variability of spectral reflectance based on the kernel technique is consistent with satellite observations over the ocean, but not over land, where both model and data have large uncertainty. RMS errors in kernel ]derived monthly global mean reflectance over the ocean compared to observations are about 0.001, and the sampling error is likely a major component.

  2. On the radiative transfer problem in a spherical medium subject to Fresnel's reflective boundary conditions

    International Nuclear Information System (INIS)

    Mohammed, M.H.H.

    2012-01-01

    Radiation transfer problem for anisotropic scattering in a spherical homogeneous, turbid medium with angular dependent (specular) and diffuse reflecting boundary is considered. The angular dependent reflectivity of the boundary is considered as Fresnel's reflection probability function. The solution of the problem containing an energy source in a medium of specular and diffuse reflecting boundaries is given in terms of the solution of the source-free problem. The source-free problem for anisotropic scattering through a homogeneous solid sphere and two concentric spheres is solved by using the Pomraning- Eddington approximation method. This method transform the integro-differential equation into two differential equations for the radiance g (x) and net flux q (x) which has an analytical solution in terms of the modified Bessel function. Two different weight functions are used to verify the boundary conditions and so, find the solution constants. The partial heat fluxes at the boundaries of a solid sphere and spherical shell of transparent and reflecting boundaries are calculated. The media are taken with or without internal black-body radiation. The calculations are carried out for various values of refractive index and different radii. The results are compared with those of the Galerkin technique

  3. Dynamics of animal movement in an ecological context: dragonfly wing damage reduces flight performance and predation success.

    Science.gov (United States)

    Combes, S A; Crall, J D; Mukherjee, S

    2010-06-23

    Much of our understanding of the control and dynamics of animal movement derives from controlled laboratory experiments. While many aspects of animal movement can be probed only in these settings, a more complete understanding of animal locomotion may be gained by linking experiments on relatively simple motions in the laboratory to studies of more complex behaviours in natural settings. To demonstrate the utility of this approach, we examined the effects of wing damage on dragonfly flight performance in both a laboratory drop-escape response and the more natural context of aerial predation. The laboratory experiment shows that hindwing area loss reduces vertical acceleration and average flight velocity, and the predation experiment demonstrates that this type of wing damage results in a significant decline in capture success. Taken together, these results suggest that wing damage may take a serious toll on wild dragonflies, potentially reducing both reproductive success and survival.

  4. Influences on the reflectance of Arctic sea ice and the impact of anthropogenic impurities on the surface shortwave radiation balance

    OpenAIRE

    Schulz, Hannes; Herber, Andreas; Birnbaum, Gerit; Seckmeyer, Gunther

    2014-01-01

    In order to investigate influences on the reflectance of snow covered Arctic sea ice, a discrete ordinate method and Mie-Theory based radiative transfer model has been set up. This model, the Snow on Sea Ice Model (SoSIM), is able to investigate changes in spectral and spectrally integrated (broadband) albedo of a multi-layer snow cover on sea ice due to varying snow microphysical parameters, atmospheric composition and incoming solar radiation. For typical conditions in the Arctic sea-ice ar...

  5. Optical coherence tomography and autofluorescence findings in chronic phototoxic maculopathy secondary to snow-reflected solar radiation

    Directory of Open Access Journals (Sweden)

    Dhananjay Shukla

    2015-01-01

    Full Text Available A professional mountain trekker presented with gradual, moderate visual decline in one eye. The subnormal vision could not be explained by the examination of anterior and posterior segment of either eye, which was unremarkable. Optical coherence tomography and autofluorescence imaging revealed subtle defects in the outer retina, which correlated with the extent of visual disturbance. A novel presentation of retinal phototoxicity due to indirect solar radiation reflected from snow in inadequately protected eyes of a chronically exposed subject is reported.

  6. Optical coherence tomography and autofluorescence findings in chronic phototoxic maculopathy secondary to snow-reflected solar radiation.

    Science.gov (United States)

    Shukla, Dhananjay

    2015-05-01

    A professional mountain trekker presented with gradual, moderate visual decline in one eye. The subnormal vision could not be explained by the examination of anterior and posterior segment of either eye, which was unremarkable. Optical coherence tomography and autofluorescence imaging revealed subtle defects in the outer retina, which correlated with the extent of visual disturbance. A novel presentation of retinal phototoxicity due to indirect solar radiation reflected from snow in inadequately protected eyes of a chronically exposed subject is reported.

  7. Infrared reflection absorption spectroscopy study of radiation-heterogeneous processes in the system of aluminum-hexane

    International Nuclear Information System (INIS)

    Gadzhieva, N.N.; Rimikhanova, A.N.; Garibov, A.A.

    2004-01-01

    Full text: Infrared reflection absorption spectroscopy (IRRAS) was applied to study the regularities of radiation conversion of hexane on the surface of aluminum. The research object was the thin polished aluminum plate by mark of AD-00 with reflection coefficient R=0.8†0.85 in infrared range λ=2.2†15 μ . As adsorbate unsaturated vapors of spectroscopy clear hexane were used. The absorption of hexane (C 2 H 14 ) was being studied manometric at pressures P=(0.1†1.0)·10 2 Pa , what corresponded to monolayer value of 1-10. The samples were irradiated with γ-quanta of 60 Co with D=1.03 Gy·s -1 doze rate. Infrared reflection spectrum when linear-polarized radiation fall on the sample under angle ψ=10 o was measured by spectrophotometer 'Specord 71 JR' in diapason of 4000-650cm -1 at the temperature by mean of special reflecting arrangements. Formation of molecular hydrogen (H 2 ) and other gaseous products of decomposition were controlled by chromotographical and infrared spectroscopical methods. The analysis of hexane infrared absorption spectra after radiation-stimulated adsorption on the surface of aluminum, points out the formation of H-bonded hydrocarbon complex ( ν∼2680cm -1 ) with much loosening of C-H bond (the molecular form of absorption) and the possibility of proceeding dissociative absorption with formation of metal-alkyls (ν∼2880, 2920, 2970 cm -1 ). Probability of the last mentioned process, which proceeds in the most defective centers, increases with increasing of γ-radiation doze. It was established that the radiation processes in hetero system Al-ads.C 6 H 14 accelerate the radiolysis of hexane. At all these the radiation decomposition of hexane in hetero system Al-ads.C 6 H 14 is accompanied by formation the surface hydrides (ν∼1700-2000 cm -1 ), acetylene (ν∼3200-3300 cm -1 ), ethylene (ν∼980 cm -1 ), and also gaseous products of molecular hydrogen decomposition (H 2 ) and hydrocarbons C 1 -C 5 (bands with maxima 770, 790

  8. Diffuse Reflectance Spectroscopy (DRS) of radiation-induced re-oxygenation in sensitive and resistant head and neck tumor xenografts

    Science.gov (United States)

    Dadgar, Sina; Rodríguez Troncoso, Joel; Rajaram, Narasimhan

    2018-02-01

    Currently, anatomical assessment of tumor volume performed several weeks after completion of treatment is the clinical standard to determine whether a cancer patient has responded to a treatment. However, functional changes within the tumor could potentially provide information regarding treatment resistance or response much earlier than anatomical changes. We have used diffuse reflectance spectroscopy to assess the short and long-term re-oxygenation kinetics of a human head and neck squamous cell carcinoma xenografts in response to radiation therapy. First, we injected UM-SCC-22B cell line into the flank of 50 mice to grow xenografts. Once the tumor volume reached 200 mm3 (designated as Day 1), the mice were distributed into radiation and control groups. Members of radiation group underwent a clinical dose of radiation of 2 Gy/day on Days 1, 4, 7, and 10 for a cumulative dose of 8 Gy. DRS spectra of these tumors were collected for 14 days during and after therapy, and the collected spectra of each tumor were converted to its optical properties using a lookup table-base inverse model. We found statistically significant differences in tumor growth rate between two groups which is in indication of the sensitivity of this cell line to radiation. We further acquired significantly different contents of hemoglobin and scattering magnitude and size in two groups. The scattering has previously been associated with necrosis. We furthermore found significantly different time-dependent changes in vascular oxygenation and tumor hemoglobin concentration in post-radiation days.

  9. The nature of inherent bactericidal activity: insights from the nanotopology of three species of dragonfly

    Science.gov (United States)

    Mainwaring, David E.; Nguyen, Song Ha; Webb, Hayden; Jakubov, Timur; Tobin, Mark; Lamb, Robert N.; Wu, Alex H.-F.; Marchant, Richard; Crawford, Russell J.; Ivanova, Elena P.

    2016-03-01

    While insect wings are widely recognised as multi-functional, recent work showed that this extends to extensive bactericidal activity brought about by cell deformation and lysis on the wing nanotopology. We now quantitatively show that subtle changes to this topography result in substantial changes in bactericidal activity that are able to span an order of magnitude. Notably, the chemical composition of the lipid nanopillars was seen by XPS and synchrotron FTIR microspectroscopy to be similar across these activity differences. Modelling the interaction between bacterial cells and the wing surface lipids of 3 species of dragonflies, that inhabit similar environments, but with distinctly different behavioural repertoires, provided the relationship between surface structure and antibacterial functionality. In doing so, these principal behavioural patterns correlated with the demands for antimicrobial efficiency dictated by differences in their foraging strategies. This work now reveals a new feature in the design elegance of natural multi-functional surfaces as well providing insights into the bactericidal mechanism underlying inherently antimicrobial materials, while suggesting that nanotopology is related to the evolutionary development of a species through the demands of its behavioural repertoire. The underlying relationship between the processes of wetting, adhesion and capillarity of the lipid nanopillars and bactericidal efficiency suggests new prospects for purely mechano-responsive antibacterial surfaces.While insect wings are widely recognised as multi-functional, recent work showed that this extends to extensive bactericidal activity brought about by cell deformation and lysis on the wing nanotopology. We now quantitatively show that subtle changes to this topography result in substantial changes in bactericidal activity that are able to span an order of magnitude. Notably, the chemical composition of the lipid nanopillars was seen by XPS and synchrotron

  10. The response of human skin commensal bacteria as a reflection of UV radiation: UV-B decreases porphyrin production.

    Directory of Open Access Journals (Sweden)

    Yanhan Wang

    Full Text Available Recent global radiation fears reflect the urgent need for a new modality that can simply determine if people are in a radiation risk of developing cancer and other illnesses. Ultraviolet (UV radiation has been thought to be the major risk factor for most skin cancers. Although various biomarkers derived from the responses of human cells have been revealed, detection of these biomarkers is cumbersome, probably requires taking live human tissues, and varies significantly depending on human immune status. Here we hypothesize that the reaction of Propionibacterium acnes (P. acnes, a human resident skin commensal, to UV radiation can serve as early surrogate markers for radiation risk because the bacteria are immediately responsive to radiation. In addition, the bacteria can be readily accessible and exposed to the same field of radiation as human body. To test our hypothesis, P. acnes was exposed to UV-B radiation. The production of porphyrins in P. acnes was significantly reduced with increasing doses of UV-B. The porphyrin reduction can be detected in both P. acnes and human skin bacterial isolates. Exposure of UV-B to P. acnes- inoculated mice led to a significant decrease in porphyrin production in a single colony of P. acnes and simultaneously induced the formation of cyclobutane pyrimidine dimers (CPD in the epidermal layers of mouse skin. Mass spectrometric analysis via a linear trap quadrupole (LTQ-Orbitrap XL showed that five peptides including an internal peptide (THLPTGIVVSCQNER of a peptide chain release factor 2 (RF2 were oxidized by UV-B. Seven peptides including three internal peptides of 60 kDa chaperonin 1 were de-oxidized by UV-B. When compared to UV-B, gamma radiation also decreased the porphyrin production of P. acnes in a dose-dependent manner, but induced a different signature of protein oxidation/de-oxidation. We highlight that uncovering response of skin microbiome to radiation will facilitate the development of pre

  11. The response of human skin commensal bacteria as a reflection of UV radiation: UV-B decreases porphyrin production.

    Science.gov (United States)

    Wang, Yanhan; Zhu, Wenhong; Shu, Muya; Jiang, Yong; Gallo, Richard L; Liu, Yu-Tsueng; Huang, Chun-Ming

    2012-01-01

    Recent global radiation fears reflect the urgent need for a new modality that can simply determine if people are in a radiation risk of developing cancer and other illnesses. Ultraviolet (UV) radiation has been thought to be the major risk factor for most skin cancers. Although various biomarkers derived from the responses of human cells have been revealed, detection of these biomarkers is cumbersome, probably requires taking live human tissues, and varies significantly depending on human immune status. Here we hypothesize that the reaction of Propionibacterium acnes (P. acnes), a human resident skin commensal, to UV radiation can serve as early surrogate markers for radiation risk because the bacteria are immediately responsive to radiation. In addition, the bacteria can be readily accessible and exposed to the same field of radiation as human body. To test our hypothesis, P. acnes was exposed to UV-B radiation. The production of porphyrins in P. acnes was significantly reduced with increasing doses of UV-B. The porphyrin reduction can be detected in both P. acnes and human skin bacterial isolates. Exposure of UV-B to P. acnes- inoculated mice led to a significant decrease in porphyrin production in a single colony of P. acnes and simultaneously induced the formation of cyclobutane pyrimidine dimers (CPD) in the epidermal layers of mouse skin. Mass spectrometric analysis via a linear trap quadrupole (LTQ)-Orbitrap XL showed that five peptides including an internal peptide (THLPTGIVVSCQNER) of a peptide chain release factor 2 (RF2) were oxidized by UV-B. Seven peptides including three internal peptides of 60 kDa chaperonin 1 were de-oxidized by UV-B. When compared to UV-B, gamma radiation also decreased the porphyrin production of P. acnes in a dose-dependent manner, but induced a different signature of protein oxidation/de-oxidation. We highlight that uncovering response of skin microbiome to radiation will facilitate the development of pre-symptomatic diagnosis

  12. Optimum combinations of visible and near-infrared reflectances for estimating the fraction of photosynthetically available radiation absorbed by plants

    Science.gov (United States)

    Podaire, Alain; Deschamps, Pierre-Yves; Frouin, R.; Asrar, Ghassem

    1991-01-01

    A useful parameter to estimate terrestrial primary productivity, that can be sensed from space, is the daily averaged fraction of Photosynthetically Available Radiation (PAR) absorbed by plants. To evaluate this parameter, investigators have relied on the fact that the relative amount of radiation reflected by a vegetated surface in the visible and near infrared depends on the fraction of the surface covered by the vegetation and therefore, correlates with absorbed PAR. They have used vegetation indices, namely normalized difference and simple ratio, to derive absorbed PAR. The problem with normalized difference and simple ratio is first, they are non linear functions of radiance or reflectance and therefore, cannot be readily applied to heterogeneous targets, second, they are used in generally nonlinear relationships, which make time integrals of the indices not proportional to primary productivity, and third, the relationships depend strongly on the type of canopy and background. To remove these limitations, linear combinations of visible and near infrared reflectances at optimum (one or two) viewing zenith angles are proposed.

  13. Testing Dragonflies as Species Richness Indicators in a Fragmented Subtropical Atlantic Forest Environment.

    Science.gov (United States)

    Renner, S; Sahlén, G; Périco, E

    2016-06-01

    We surveyed 15 bodies of water among remnants of the Atlantic Forest biome in southern Brazil for adult dragonflies and damselflies to test whether an empirical selection method for diversity indicators could be applied in a subtropical ecosystem, where limited ecological knowledge on species level is available. We found a regional species pool of 34 species distributed in a nested subset pattern with a mean of 11.2 species per locality. There was a pronounced difference in species composition between spring, summer, and autumn, but no differences in species numbers between seasons. Two species, Homeoura chelifera (Selys) and Ischnura capreolus (Hagen), were the strongest candidates for regional diversity indicators, being found only at species-rich localities in our surveyed area and likewise in an undisturbed national forest reserve, serving as a reference site for the Atlantic Forest. Using our selection method, we found it possible to obtain a tentative list of diversity indicators without having detailed ecological information of each species, providing a reference site is available for comparison. The method thus allows for indicator species to be selected in blanco from taxonomic groups that are little known. We hence argue that Odonata can already be incorporated in ongoing assessment programs in the Neotropics, which would also increase the ecological knowledge of the group and allow extrapolation to other taxa.

  14. A Personal Reflection on the History of Radiation Oncology at Memorial Sloan-Kettering Cancer Center

    International Nuclear Information System (INIS)

    Chu, Florence C.H.

    2011-01-01

    Purpose: To provide a historical and personal narrative of the development of radiation oncology at Memorial Sloan-Kettering Cancer Center (MSKCC), from its founding more than 100 years ago to the present day. Methods and Materials: Historical sources include the Archives of MSKCC, publications by members of MSKCC, the author's personal records and recollections, and her communications with former colleagues, particularly Dr. Basil Hilaris, Dr. Zvi Fuks, and Dr. Beryl McCormick. Conclusions: The author, who spent 38 years at MSKCC, presents the challenges and triumphs of MSKCC's Radiation Oncology Department and details MSKCC's breakthroughs in radiation oncology. She also describes MSKCC's involvement in the founding of the American Society for Therapeutic Radiology and Oncology.

  15. Elemental concentration in normal skin and fibroepithelial polip lesions by synchrotron radiation total reflection X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Soares, Julio C.A.C.R.; Canellas, Catarine G.L.; Lopes, Ricardo T.; Anjos, Marcelino J.

    2011-01-01

    In this work, the concentrations of trace elements were measured in acrochordon, a skin lesion also known as skin tag or fibroepithelial polyp, as well as in normal skin from the same patient. The samples were analysed by Synchrotron Radiation Total Reflection X- ray Fluorescence (SRTXRF) in the Synchrotron Light National Laboratory (LNLS) in Campinas/Sao Paulo-Brazil. The collection of lesion and healthy skin samples, including papillary dermis and epidermis, has involved 17 patients. It was evaluated the presence of P, S, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, Br and Rb in the paired samples, which were compared, and significant differences were found in some of them. (author)

  16. Recent results of synchrotron radiation induced total reflection X-ray fluorescence analysis at HASYLAB, beamline L

    Energy Technology Data Exchange (ETDEWEB)

    Streli, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria)]. E-mail: streli@ati.ac.at; Pepponi, G. [ITC-irst, Povo (Italy); Wobrauschek, P. [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria); Jokubonis, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria); Falkenberg, G. [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, D-22603 Hamburg (Germany); Zaray, G. [Institute of Inorganic and Applied Chemistry, 3 EOTVOS Univ, Budapest (Hungary); Broekaert, J. [Institute of Anorganic and Applied Chemistry, University Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Fittschen, U. [Institute of Anorganic and Applied Chemistry, University Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Peschel, B. [Institute of Anorganic and Applied Chemistry, University Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany)

    2006-11-15

    At the Hamburger Synchrotronstrahlungslabor (HASYLAB), Beamline L, a vacuum chamber for synchrotron radiation-induced total reflection X-ray fluorescence analysis, is now available which can easily be installed using the adjustment components for microanalysis present at this beamline. The detector is now in the final version of a Vortex silicon drift detector with 50-mm{sup 2} active area from Radiant Detector Technologies. With the Ni/C multilayer monochromator set to 17 keV extrapolated detection limits of 8 fg were obtained using the 50-mm{sup 2} silicon drift detector with 1000 s live time on a sample containing 100 pg of Ni. Various applications are presented, especially of samples which are available in very small amounts: As synchrotron radiation-induced total reflection X-ray fluorescence analysis is much more sensitive than tube-excited total reflection X-ray fluorescence analysis, the sampling time of aerosol samples can be diminished, resulting in a more precise time resolution of atmospheric events. Aerosols, directly sampled on Si reflectors in an impactor were investigated. A further application was the determination of contamination elements in a slurry of high-purity Al{sub 2}O{sub 3}. No digestion is required; the sample is pipetted and dried before analysis. A comparison with laboratory total reflection X-ray fluorescence analysis showed the higher sensitivity of synchrotron radiation-induced total reflection X-ray fluorescence analysis, more contamination elements could be detected. Using the Si-111 crystal monochromator also available at beamline L, XANES measurements to determine the chemical state were performed. This is only possible with lower sensitivity as the flux transmitted by the crystal monochromator is about a factor of 100 lower than that transmitted by the multilayer monochromator. Preliminary results of X-ray absorption near-edge structure measurements for As in xylem sap from cucumber plants fed with As(III) and As(V) are

  17. Recent results of synchrotron radiation induced total reflection X-ray fluorescence analysis at HASYLAB, beamline L

    International Nuclear Information System (INIS)

    Streli, C.; Pepponi, G.; Wobrauschek, P.; Jokubonis, C.; Falkenberg, G.; Zaray, G.; Broekaert, J.; Fittschen, U.; Peschel, B.

    2006-01-01

    At the Hamburger Synchrotronstrahlungslabor (HASYLAB), Beamline L, a vacuum chamber for synchrotron radiation-induced total reflection X-ray fluorescence analysis, is now available which can easily be installed using the adjustment components for microanalysis present at this beamline. The detector is now in the final version of a Vortex silicon drift detector with 50-mm 2 active area from Radiant Detector Technologies. With the Ni/C multilayer monochromator set to 17 keV extrapolated detection limits of 8 fg were obtained using the 50-mm 2 silicon drift detector with 1000 s live time on a sample containing 100 pg of Ni. Various applications are presented, especially of samples which are available in very small amounts: As synchrotron radiation-induced total reflection X-ray fluorescence analysis is much more sensitive than tube-excited total reflection X-ray fluorescence analysis, the sampling time of aerosol samples can be diminished, resulting in a more precise time resolution of atmospheric events. Aerosols, directly sampled on Si reflectors in an impactor were investigated. A further application was the determination of contamination elements in a slurry of high-purity Al 2 O 3 . No digestion is required; the sample is pipetted and dried before analysis. A comparison with laboratory total reflection X-ray fluorescence analysis showed the higher sensitivity of synchrotron radiation-induced total reflection X-ray fluorescence analysis, more contamination elements could be detected. Using the Si-111 crystal monochromator also available at beamline L, XANES measurements to determine the chemical state were performed. This is only possible with lower sensitivity as the flux transmitted by the crystal monochromator is about a factor of 100 lower than that transmitted by the multilayer monochromator. Preliminary results of X-ray absorption near-edge structure measurements for As in xylem sap from cucumber plants fed with As(III) and As(V) are reported. Detection

  18. ALBEMO, a program for the calculation of the radiation transport in void volumes with reflecting walls

    International Nuclear Information System (INIS)

    Mueller, K.; Vossebrecker, H.

    The Monte Carlo Program ALBEMO calculates the distribution of neutrons and gamma rays in void volumes which are bounded by reflecting walls with x, y, z coordinates. The program is based on the albedo method. The effect of significant simplifying assumptions is investigated. Comparisons with experiments show satisfying agreement

  19. Trapping of microwave radiation in hollow polypyrrole microsphere through enhanced internal reflection: A novel approach

    Science.gov (United States)

    Panigrahi, Ritwik; Srivastava, Suneel K.

    2015-01-01

    In present work, spherical core (polystyrene, PS)/shell (polypyrrole, PPy) has been synthesized via in situ chemical oxidative copolymerization of pyrrole (Py) on the surface of sulfonated PS microsphere followed by the formation of hollow polypyrrole (HPPy) shell by dissolving PS inner core in THF. Thereafter, we first time established that such fabricated novel art of morphology acts as a conducting trap in absorbing electromagnetic (EM) wave by internal reflection. Further studies have been extended on the formation of its silver nanocomposites HPPy/Ag to strengthen our contention on this novel approach. Our investigations showed that electromagnetic interference (EMI) shielding efficiency (SE) of HPPy (34.5-6 dB) is significantly higher compared to PPy (20-5 dB) in the frequency range of 0.5-8 GHz due to the trapping of EM wave by internal reflection. We also observed that EMI shielding is further enhanced to 59-23 in 10 wt% Ag loaded HPPy/Ag-10. This is attributed to the simultaneous contribution of internal reflection as well as reflection from outer surface. Such high EMI shielding capacity using conducting polymers are rarely reported.

  20. Self-reflection and self-transmission of pulsed radiation by laser-evaporated media

    Science.gov (United States)

    Furzikov, Nickolay P.

    1991-05-01

    Analysis of the known laser-induced evaporation (thermodestruction) model predicts the quasiperiodic oscillation of the effective absorption depth between its normal value and some minute quantity consisting of a part of the incident wavelength. This prediction explains the experimental data on the polymer laser ablation depth as well as the reflection transient drop of the laserdestructed aluminum.

  1. Total reflection X-ray fluorescence with synchrotron radiation applied to biological and environmental samples

    International Nuclear Information System (INIS)

    Simabuco, S.M.; Matsumoto, E.; Jesus, E.F.O.; Lopes, R.T.; Perez, C.; Nascimento Filho, V.F.; Costa, R.S.S.; Tavares do Carmo, M.G.; Saunders, C.

    2001-01-01

    Full text: The Total Reflection X-ray Fluorescence has been applied for trace elements in water and aqueous solutions, environmental samples and biological materials after sample preparation and to surface analysis of silicon wafers. The present paper shows some results of applications for rainwater, atmospheric particulate material, colostrum and nuclear samples. (author)

  2. Use of Maple Seeding Canopy Reflectance Dataset for Validation of SART/LEAFMOD Radiative Transfer Model

    Science.gov (United States)

    Bond, Barbara J.; Peterson, David L.

    1999-01-01

    This project was a collaborative effort by researchers at ARC, OSU and the University of Arizona. The goal was to use a dataset obtained from a previous study to "empirically validate a new canopy radiative-transfer model (SART) which incorporates a recently-developed leaf-level model (LEAFMOD)". The document includes a short research summary.

  3. Determining composition of a substance by the use of both reflected and transmitted radiation

    International Nuclear Information System (INIS)

    Teller, S.

    1975-01-01

    An apparatus for the determination of the content of sulfur in hydrocarbon fuels comprising a primary and a secondary source of γ- or x-rays arranged on opposite sides of a test zone and a detector connected to a recording device for detecting and recording backscattered and transmitted rays emitted by the radiation sources is described

  4. Standard Practice for Calculation of Photometric Transmittance and Reflectance of Materials to Solar Radiation

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1988-01-01

    1.1 This practice describes the calculation of luminous (photometric) transmittance and reflectance of materials from spectral radiant transmittance and reflectance data obtained from Test Method E 903. 1.2 Determination of luminous transmittance by this practice is preferred over measurement of photometric transmittance by methods using the sun as a source and a photometer as detector except for transmitting sheet materials that are inhomogeneous, patterned, or corrugated. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  5. Trapping of microwave radiation in hollow polypyrrole microsphere through enhanced internal reflection: A novel approach

    OpenAIRE

    Ritwik Panigrahi; Suneel K. Srivastava

    2015-01-01

    In present work, spherical core (polystyrene, PS)/shell (polypyrrole, PPy) has been synthesized via in situ chemical oxidative copolymerization of pyrrole (Py) on the surface of sulfonated PS microsphere followed by the formation of hollow polypyrrole (HPPy) shell by dissolving PS inner core in THF. Thereafter, we first time established that such fabricated novel art of morphology acts as a conducting trap in absorbing electromagnetic (EM) wave by internal reflection. Further studies have bee...

  6. Thin film transistors on plastic substrates with reflective coatings for radiation protection

    Science.gov (United States)

    Wolfe, Jesse D [Fairfield, CA; Theiss, Steven D [Woodbury, MN; Carey, Paul G [Mountain View, CA; Smith, Patrick M [San Ramon, CA; Wickbold, Paul [Walnut Creek, CA

    2006-09-26

    Fabrication of silicon thin film transistors (TFT) on low-temperature plastic substrates using a reflective coating so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The TFT can be used in large area low cost electronics, such as flat panel displays and portable electronics such as video cameras, personal digital assistants, and cell phones.

  7. Australian radiation therapy – Part two: Reflections of the past, the present, the future

    International Nuclear Information System (INIS)

    Merchant, Susan; Halkett, Georgia; Sale, Charlotte

    2014-01-01

    Introduction: Documentation on the history of Australian radiotherapy is limited. This study provides radiation therapists' (RTs) perspectives of the people, workplace, and work practices in Australian radiotherapy centres from 1960 onwards. It provides a follow-up to our previous study: Australian radiation therapy: An overview – Part one, which outlines the history and development of radiotherapy from conception until present day. Methods: Four focus groups were conducted on separate occasions in 2010, one in South Australia and three in Victoria, Australia. Participants who worked in radiotherapy were purposively selected to ensure a range of experience, age, and years of work. Results: From a RT perspective, radiotherapy has evolved from a physically demanding ‘hands-on’ work environment, often with unpleasant sights and smells of disease, to a more technology-driven workplace. Conclusion: Understanding these changes and their subsequent effects on the role of Australian RTs will assist future directions in advanced role development

  8. Australian radiation therapy – Part two: Reflections of the past, the present, the future

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Susan [Radiation Oncology Department, Royal Adelaide Hospital, Adelaide, SA (Australia); Curtin Health Innovative Research Institute, Curtin University, Perth, WA (Australia); Halkett, Georgia [Curtin Health Innovative Research Institute, Curtin University, Perth, WA (Australia); Sale, Charlotte [Radiation Oncology, Andrew Love Cancer Centre, Barwon Health, Geelong, Vic. (Australia); Radiation Oncology Department, Royal Adelaide Hospital, Adelaide, SA (Australia); Collaboration: Grad Cert Grief & Pall Care Counselling, MIR

    2014-02-15

    Introduction: Documentation on the history of Australian radiotherapy is limited. This study provides radiation therapists' (RTs) perspectives of the people, workplace, and work practices in Australian radiotherapy centres from 1960 onwards. It provides a follow-up to our previous study: Australian radiation therapy: An overview – Part one, which outlines the history and development of radiotherapy from conception until present day. Methods: Four focus groups were conducted on separate occasions in 2010, one in South Australia and three in Victoria, Australia. Participants who worked in radiotherapy were purposively selected to ensure a range of experience, age, and years of work. Results: From a RT perspective, radiotherapy has evolved from a physically demanding ‘hands-on’ work environment, often with unpleasant sights and smells of disease, to a more technology-driven workplace. Conclusion: Understanding these changes and their subsequent effects on the role of Australian RTs will assist future directions in advanced role development.

  9. Variation of reflected radiation from all reflectors of a flat plate solar collector during a year

    International Nuclear Information System (INIS)

    Pavlović, Zoran T.; Kostić, Ljiljana T.

    2015-01-01

    In this paper the impact of flat plate reflectors (bottom, top, left and right reflectors) made of Al, on total solar radiation on a solar collector during a day time over a whole year is analyzed. An analytical model for determining optimum tilt angles of a collector and reflectors for any point on the Earth is proposed. Variations of reflectors' optimal inclination angles with changes of the collector's optimal tilt angle during the year are also calculated. Optimal inclination angles of the reflectors for the South directed solar collector are calculated and compared to experimental data. It is shown that optimal inclination of the bottom reflector is the lowest in December and the highest in June, while for the top reflector the lowest value is in June and the highest value is in December. On the other hand, optimal inclination of the left and right side reflectors for optimum tilt angle of the collector does not change during the year and it is 66°. It is found that intensity of the solar radiation on the collector increases for about 80% in the summer period (June–September) by using optimally inclined reflectors, in comparison to the collector without reflectors. - Highlights: • The impacts of flat plate reflectors on solar radiation on the collector are given. • The results of the optimal inclinations of reflectors during the year are shown. • The solar radiation on the collector with reflectors is 80% higher in the summer. • This model may be applied on thermal, PV, PV/T and energy harvesting systems

  10. Personal reflections on the highlights and changes in radiation and radioisotope measurement applications

    International Nuclear Information System (INIS)

    Gardner, Robin P.; Lee, Kyoung O.

    2015-01-01

    This paper describes the recent changes that the authors have perceived in the use of radiation and radioisotope measurement applications. The first change is that due to the increased use of Monte Carlo simulation which has occurred from a normal evolutionary process. This is due in large part to the increased accuracy that is being obtained by the use of detector response functions (DRFs) and the simultaneous increased computational efficiency that has become available with these DRFs, the availability of a greatly improved weight windows variance reduction method, and the availability of inexpensive computer clusters. This first change is a happy one. The other change that is occurring is in response to recent terrorist activities. That change is the replacement or major change in the use of long-lived radioisotopes in radioisotope measurement and other radioisotope source applications. In general this can be done by improving the security of these radioisotope sources or by replacing them altogether by using machine sources of radiation. In either case one would like to preclude altogether or at least minimize the possibility of terrorists being able to obtain radioisotopes and use them for clandestine purposes. - Highlights: • Recent changes in radioisotope measurement applications. • Improvements in Monte Carlo simulation for treating radioisotope measurement applications. • Replacement of radioisotope sources with machine sources of radiation.

  11. A fast radiative transfer model for visible through shortwave infrared spectral reflectances in clear and cloudy atmospheres

    International Nuclear Information System (INIS)

    Wang, Chenxi; Yang, Ping; Nasiri, Shaima L.; Platnick, Steven; Baum, Bryan A.; Heidinger, Andrew K.; Liu, Xu

    2013-01-01

    A computationally efficient radiative transfer model (RTM) for calculating visible (VIS) through shortwave infrared (SWIR) reflectances is developed for use in satellite and airborne cloud property retrievals. The full radiative transfer equation (RTE) for combinations of cloud, aerosol, and molecular layers is solved approximately by using six independent RTEs that assume the plane-parallel approximation along with a single-scattering approximation for Rayleigh scattering. Each of the six RTEs can be solved analytically if the bidirectional reflectance/transmittance distribution functions (BRDF/BTDF) of the cloud/aerosol layers are known. The adding/doubling (AD) algorithm is employed to account for overlapped cloud/aerosol layers and non-Lambertian surfaces. Two approaches are used to mitigate the significant computational burden of the AD algorithm. First, the BRDF and BTDF of single cloud/aerosol layers are pre-computed using the discrete ordinates radiative transfer program (DISORT) implemented with 128 streams, and second, the required integral in the AD algorithm is numerically implemented on a twisted icosahedral mesh. A concise surface BRDF simulator associated with the MODIS land surface product (MCD43) is merged into a fast RTM to accurately account for non-isotropic surface reflectance. The resulting fast RTM is evaluated with respect to its computational accuracy and efficiency. The simulation bias between DISORT and the fast RTM is large (e.g., relative error >5%) only when both the solar zenith angle (SZA) and the viewing zenith angle (VZA) are large (i.e., SZA>45° and VZA>70°). For general situations, i.e., cloud/aerosol layers above a non-Lambertian surface, the fast RTM calculation rate is faster than that of the 128-stream DISORT by approximately two orders of magnitude. -- Highlights: ► An efficient radiative transfer model is developed for cloud remote sensing. ► Multi-layered clouds and a non-Lambertian surface can be fully considered.

  12. The Dragonfly Nearby Galaxies Survey. III. The Luminosity Function of the M101 Group

    Science.gov (United States)

    Danieli, Shany; van Dokkum, Pieter; Merritt, Allison; Abraham, Roberto; Zhang, Jielai; Karachentsev, I. D.; Makarova, L. N.

    2017-03-01

    We obtained follow-up HST observations of the seven low surface brightness galaxies discovered with the Dragonfly Telephoto Array in the field of the massive spiral galaxy M101. Out of the seven galaxies, only three were resolved into stars and are potentially associated with the M101 group at D = 7 Mpc. Based on HST ACS photometry in the broad F606W and F814W filters, we use a maximum likelihood algorithm to locate the Tip of the Red Giant Branch in galaxy color-magnitude diagrams. Distances are {6.38}-0.35+0.35,{6.87}-0.30+0.21 and {6.52}-0.27+0.25 {Mpc} and we confirm that they are members of the M101 group. Combining the three confirmed low-luminosity satellites with previous results for brighter group members, we find the M101 galaxy group to be a sparsely populated galaxy group consisting of seven group members, down to M V = -9.2 mag. We compare the M101 cumulative luminosity function to that of the Milky Way and M31. We find that they are remarkably similar; in fact, the cumulative luminosity function of the M101 group gets even flatter for fainter magnitudes, and we show that the M101 group might exhibit the two known small-scale flaws in the ΛCDM model, namely “the missing satellite” problem and the “too big to fail” problem. Kinematic measurements of M101's satellite galaxies are required to determine whether the “too big to fail” problem does in fact exist in the M101 group.

  13. Radiation interception and use, and spectral reflectance of contrasting canopies of autumn sown faba beans and semi-leafless peas

    International Nuclear Information System (INIS)

    Ridao, E.; Oliveira, C.F.; Conde, J.R.; Minguez, M.I.

    1996-01-01

    Water deficits in faba bean produced a change in leaf angle that lowered the fraction of photosynthetically active radiation intercepted (R pi ) by the canopy, when compared to irrigated faba beans. This response was not found in a semi-leafless pea crop for its canopy structure was maintained rigid by tendrils. These contrasting behaviours were quantified by changes in photosynthetically active radiation (R p ) extinction coefficients (K). For irrigated faba beans, an average value for K of 0.78 is proposed for R p interception modelling. In the case of water stressed faba beans, the possibility of using a water stress dependent K is raised. The canopy architecture of semi-leafless peas may allow the use of one K (0.50) for the two water regimes. Radiation use efficiency (RUE) showed a two phase behaviour: before (RUEbg) and after (RUEag) the beginning of grain filling. In addition, changes in RUE were also due to water supply and affected RUEag values, although in a different way in peas than in faba beans. The reflectance properties of these canopies allowed for an evaluation of crop biomass and also enhanced their contrasting characteristics. The Soil Adjusted Vegetation Index (SAVI2) was used here as a means to estimate R pi . The relationships between SAVI2 and R pi were near-linear in faba beans and linear in peas. Crop biomass was then estimated with these relationships and with the acquired information on the two phase RUE of each species and water regime. (author)

  14. Fast and Accurate Hybrid Stream PCRTMSOLAR Radiative Transfer Model for Reflected Solar Spectrum Simulation in the Cloudy Atmosphere

    Science.gov (United States)

    Yang, Qiguang; Liu, Xu; Wu, Wan; Kizer, Susan; Baize, Rosemary R.

    2016-01-01

    A hybrid stream PCRTM-SOLAR model has been proposed for fast and accurate radiative transfer simulation. It calculates the reflected solar (RS) radiances with a fast coarse way and then, with the help of a pre-saved matrix, transforms the results to obtain the desired high accurate RS spectrum. The methodology has been demonstrated with the hybrid stream discrete ordinate (HSDO) radiative transfer (RT) model. The HSDO method calculates the monochromatic radiances using a 4-stream discrete ordinate method, where only a small number of monochromatic radiances are simulated with both 4-stream and a larger N-stream (N = 16) discrete ordinate RT algorithm. The accuracy of the obtained channel radiance is comparable to the result from N-stream moderate resolution atmospheric transmission version 5 (MODTRAN5). The root-mean-square errors are usually less than 5x10(exp -4) mW/sq cm/sr/cm. The computational speed is three to four-orders of magnitude faster than the medium speed correlated-k option MODTRAN5. This method is very efficient to simulate thousands of RS spectra under multi-layer clouds/aerosols and solar radiation conditions for climate change study and numerical weather prediction applications.

  15. Reflection groups

    International Nuclear Information System (INIS)

    Eggermont, G.

    2006-01-01

    In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

  16. Application of dragonfly algorithm for optimal performance analysis of process parameters in turn-mill operations- A case study

    Science.gov (United States)

    Vikram, K. Arun; Ratnam, Ch; Lakshmi, VVK; Kumar, A. Sunny; Ramakanth, RT

    2018-02-01

    Meta-heuristic multi-response optimization methods are widely in use to solve multi-objective problems to obtain Pareto optimal solutions during optimization. This work focuses on optimal multi-response evaluation of process parameters in generating responses like surface roughness (Ra), surface hardness (H) and tool vibration displacement amplitude (Vib) while performing operations like tangential and orthogonal turn-mill processes on A-axis Computer Numerical Control vertical milling center. Process parameters like tool speed, feed rate and depth of cut are considered as process parameters machined over brass material under dry condition with high speed steel end milling cutters using Taguchi design of experiments (DOE). Meta-heuristic like Dragonfly algorithm is used to optimize the multi-objectives like ‘Ra’, ‘H’ and ‘Vib’ to identify the optimal multi-response process parameters combination. Later, the results thus obtained from multi-objective dragonfly algorithm (MODA) are compared with another multi-response optimization technique Viz. Grey relational analysis (GRA).

  17. New optical scheme for differential measurements of diffraction reflection intensity on X-radiation sliding incidence

    International Nuclear Information System (INIS)

    Golovin, A.L.; Mas', E.T.

    1989-01-01

    An X-ray optical scheme for differential measurements of X-ray diffraction under sliding incidence conditions is proposed and an attachment design realizng this scheme, using standard equipment, is described. The main feature of the scheme is the following: collimation according to the Bragg angle is carried out for the reflected beam rather than the incident one. Goniometers can be used from DRON, TRS, GS-5 and other spectrometers. The goniometer head carrying the sample is standard, it is a part of the DRON, TRS and DTS. The crystal analyzer is fixed on the attachment. The angular position of the crystal monochromator is controlled by an inductive sensor. The experimental differential curves of X-ray diffraction under conditions of sliding incidence, taken for a silicon crystal having the 111 orientation, are given as well

  18. Effect of temperature extremes on the spatial dynamics of predator–prey interactions: a case study with dragonfly nymphs and newt larvae

    Czech Academy of Sciences Publication Activity Database

    Smolinský, Radovan; Gvoždík, Lumír

    2014-01-01

    Roč. 39, January (2014), s. 12-16 ISSN 0306-4565 R&D Projects: GA ČR GAP506/10/2170 Institutional support: RVO:68081766 Keywords : Climate change * Dragonfly * Heat waves * Newt * Predator–prey interaction * Thermal stress * Thermal adaptation Subject RIV: EG - Zoology Impact factor: 1.505, year: 2014

  19. Fish samples as bioindicator of environmental quality: synchrotron radiation total reflection X-ray fluorescence analysis (SR-TXRF)

    International Nuclear Information System (INIS)

    Vives, Ana Elisa Sirito de; Moreira, Silvana; Brienza, Sandra Maria Boscolo; Zucchi, Orgheda Luiza Araujo Domingues; Nascimento Filho, Virgilio Franco do Centro de Energia Nuclear na Agricultura , Piracicaba, SP; Brazil)

    2005-01-01

    In this study fish were used as bioindicators of environmental contamination. The species were collected in Piracicaba River, Sao Paulo state, Brazil and the toxic elements concentrations were determined in muscle tissue and viscus (liver, intestine and stomach) by Synchrotron Radiation Total Reflection X-Ray Fluorescence Analysis (SR-TXRF). Were determined the elements Ti, Cr, Mn, Fe, Ni, Cu, Zn and Ba. The results were compared with values established by Brazilian Legislation for general food. The elements concentrations evidenced potential risk to human health and environmental quality alteration of the studied area. The measurements were realized at the 'Laboratorio Nacional de Luz Sincrotron' (LNLS) located in Campinas, Sao Paulo State, Brazil. (author)

  20. Fish samples as bioindicator of environmental quality: synchrotron radiation total reflection X-ray fluorescence analysis (SR-TXRF)

    Energy Technology Data Exchange (ETDEWEB)

    Vives, Ana Elisa Sirito de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: Silvana@fec.unicamp.br; Brienza, Sandra Maria Boscolo [Universidade Metodista de Piracicaba (UNIMEP), SP (Brazil). Faculdade de Ciencias Matematicas, da Natureza e de Tecnologia da Informacao]. E-mail: sbrienza@unimep.br; Zucchi, Orgheda Luiza Araujo Domingues [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Nascimento Filho, Virgilio Franco do [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil)]. E-mail: virgilio@cena.usp.br

    2005-07-01

    In this study fish were used as bioindicators of environmental contamination. The species were collected in Piracicaba River, Sao Paulo state, Brazil and the toxic elements concentrations were determined in muscle tissue and viscus (liver, intestine and stomach) by Synchrotron Radiation Total Reflection X-Ray Fluorescence Analysis (SR-TXRF). Were determined the elements Ti, Cr, Mn, Fe, Ni, Cu, Zn and Ba. The results were compared with values established by Brazilian Legislation for general food. The elements concentrations evidenced potential risk to human health and environmental quality alteration of the studied area. The measurements were realized at the 'Laboratorio Nacional de Luz Sincrotron' (LNLS) located in Campinas, Sao Paulo State, Brazil. (author)

  1. Do the UK workplace Radon Action Levels reflect the radiation dose received by the occupants?

    International Nuclear Information System (INIS)

    Denman, A.R.; Parkinson, S.; Barker, S.P.; Marley, F.; Phillips, P.S.

    1999-01-01

    In the UK, Action Levels for radon have been established at 400 Bq m -3 for the workplace and 200 Bq m -3 for the home. We have estimated the dose received by occupants of rooms with radon levels near or above the Action Level, using hourly radon readings, and a questionnaire to record occupancy. In the workplace, results for 73 staff suggest that doses are lower than expected, partly due to part-time working and partly due to the mobility of staff. The 75% quantile for the series, corrected to a 37 hour week, is 5.2 mSv at 400 Bq m -3 . Compared to the current annual limit for radiation workers, the Action Level could be increased, but the current Action Level is compatible with the recent EEC Directive requiring a lower dose limit. However, when raised radon levels in the workplace were reduced by remediation in the series we studied, the dose reduction to staff was consistently around half of the radon level reduction. Although it would be appropriate to study more locations, this suggests an Action Level for remediated workplaces of 200 Bq m -3 . Finally, in a limited series of dose assessments in domestic properties, we found that doses could considerably exceed 5 mSv at the 200 Bq m -3 Action Level, primarily because the sample included an example of high occupancy, in our case several Asian wives in purdah, whose occupancy was almost total. (author)

  2. Spatial and temporal distribution of dragonflies naiads in wetlands La Vaca and Santa Maria del Lago, Bogota, Colombia

    International Nuclear Information System (INIS)

    Moreno Pallares, Maria Ines; Guillot Monroy, Gabriel Hernando

    2012-01-01

    We evaluated the spatial and temporal variation in communities of dragonfly's naiads and their association to the habitat rehabilitation status in La Vaca and Santa Maria del Lago wetlands. Four samplings were carried out in several sites of each during a year. Macroinvertebrates were collected at the entry and exit flow, and in open waters of the wetlands using standard techniques. We found a gradient in the distribution of the abundance of nymphs in both wetlands, where naiads community had the highest number of individuals in the places located farther from the dumping sites. Comparing the community s composition between wetlands La Vaca and Santa Maria del Lago through the beta diversity, heterogeneity was found in both ecosystems. The gradient in the distribution of the abundance of naiads observed in both wetlands fits with to a response of the species in terms of tolerance to the environmental variables.

  3. Keeping the golden mean: plant stiffness and anatomy as proximal factors driving endophytic oviposition site selection in a dragonfly.

    Science.gov (United States)

    Matushkina, Natalia; Lambret, Philippe; Gorb, Stanislav

    2016-12-01

    Oviposition site selection is a crucial component of habitat selection in dragonflies. The presence of appropriate oviposition plants at breeding waters is considered to be one of the key habitat determinants for species laying eggs endophytically. Thus, Lestes macrostigma, a species which is regarded as threatened in Europe because of its highly disjunct distribution, typically prefers to lay eggs in the sea club rush Bolboschoenus maritimus. However, little is known about how the anatomical and mechanical properties of plant tissues determine the choice of L. macrostigma females. We examined green shoots of six plant species used by L. macrostigma for oviposition, either in the field (actual oviposition plants) or under experimental conditions (potential oviposition plants), to analyse anatomical and mechanical properties of shoots in a framework of known preferences regarding plant substrates for oviposition. As expected, the anatomy of shoots differed between representatives of two plant families, Cyperaceae and Juncaceae, most essentially in the distribution of supporting bundles and the presence of large aeriferous cavities that may affect egg placing within a shoot. The force necessary to puncture the tested plant samples ranged from 360 to 3298 mN, and their local stiffness ranged from 777 to 3363N/m. We show that the shoots of B. maritimus, the plant most preferred by L. macrostigma, have intermediate characteristics regarding both the stiffness and specific anatomical characteristics. The bending stiffness of the ovipositor in L. macrostigma was estimated as 1414N/m, one of the highest values recorded for zygopteran dragonflies so far. The ecological and behavioural implications of plant choice mechanisms in L. macrostigma are discussed in the context of the disjunct distribution of this species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Relative Influence of Prior Life Stages and Habitat Variables on Dragonfly (Odonata: Gomphidae Densities among Lake Sites

    Directory of Open Access Journals (Sweden)

    Alysa Remsburg

    2011-04-01

    Full Text Available Many aquatic species have discrete life stages, making it important to understand relative influences of the different habitats occupied within those populations. Although population demographics in one stage can carry over to spatially separated life stages, most studies of habitat associations have been restricted to a single life stage. Among Gomphidae dragonflies (Odonata: Anisoptera, recruitment via adult oviposition establishes initial population sizes of the aquatic larvae. However, spatial variability in larval survivorship could obscure the relationship between adult and larval densities. This study uses surveys conducted during 2005 and 2006 of Gomphidae larval, emergence, and adult stages from 22 lake sites in northern Wisconsin, USA, to investigate (1 whether the Gomphidae density of each life stage correlated spatially with that of the preceding life stage and (2 what habitat factors help explain variation in densities at each life stage. Results indicated that adult densities from the previous season helped predict densities of early-instar larvae. This finding suggests that oviposition site selection controlled the local larval distribution more than larval survivorship or movement. Late-instar larval densities helped predict densities of emerging Gomphidae later the same season, suggesting that variation in survivorship of final-instar larvae among sites is small relative to the variation in larval recruitment. This study demonstrates that locations with higher densities of odonates in the water also have higher densities of odonates on land. In addition to the densities of Gomphidae in previous life stages, water clarity helped predict larval densities, and riparian wetland vegetation helped predict emergent dragonfly densities.

  5. Evaluation of drought and UV radiation impacts on above-ground biomass of mountain grassland by spectral reflectance and thermal imaging techniques

    Czech Academy of Sciences Publication Activity Database

    Novotná, Kateřina; Klem, Karel; Holub, Petr; Rapantová, Barbora; Urban, Otmar

    2016-01-01

    Roč. 9, 1-2 (2016), s. 21-30 ISSN 1803-2451 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : above-ground biomass * drought stress * grassland * UV radiation * precipitation * spectral reflectance * thermal imaging Subject RIV: EH - Ecology, Behaviour

  6. Vacuum fluctuations and radiation reaction contributions to the resonance dipole-dipole interaction between two atoms near a reflecting boundary

    Science.gov (United States)

    Zhou, Wenting; Rizzuto, Lucia; Passante, Roberto

    2018-04-01

    We investigate the resonance dipole-dipole interaction energy between two identical atoms, one in the ground state and the other in the excited state, interacting with the electromagnetic field in the presence of a perfectly reflecting plane boundary. The atoms are prepared in a correlated (symmetric or antisymmetric) Bell-type state. Following a procedure due to Dalibard et al. [J. Dalibard et al., J. Phys. (Paris) 43, 1617 (1982);, 10.1051/jphys:0198200430110161700 J. Phys. (Paris) 45, 637 (1984), 10.1051/jphys:01984004504063700], we separate the contributions of vacuum fluctuations and radiation reaction (source) field to the resonance interaction energy between the two atoms and show that only the source field contributes to the interatomic interaction, while vacuum field fluctuations do not. By considering specific geometric configurations of the two-atom system with respect to the mirror and specific choices of dipole orientations, we show that the presence of the mirror significantly affects the resonance interaction energy and that different features appear with respect to the case of atoms in free space, for example, a change in the spatial dependence of the interaction. Our findings also suggest that the presence of a boundary can be exploited to tailor and control the resonance interaction between two atoms, as well as the related energy transfer process. The possibility of observing these phenomena is also discussed.

  7. Radiative transfer in shrub savanna sites in Niger: preliminary results from HAPEX-Sahel. 1. Modelling surface reflectance using a geometric-optical approach

    International Nuclear Information System (INIS)

    Franklin, J.; Duncan, J.; Huete, A.R.; Leeuwen, W.J.D. van; Li, X.; Bégué, A.

    1994-01-01

    To use optical remote sensing to monitor land surface-climate interactions over large areas, algorithms must be developed to relate multispectral measurements to key variables controlling the exchange of matter (water, carbon dioxide) and energy between the land surface and the atmosphere. The proportion of the ground covered by vegetation and the interception of photosynthetically active radiation (PAR) by vegetation are examples of two variables related to evapotranspiration and primary production, respectively. An areal-proportion model of the multispectral reflectance of shrub savanna, composed of scattered shrubs with a grass, forb or soil understory, predicted the reflectance of two 0.5 km 2 sites as the area-weighted average of the shrub and understory or ‘background’ reflectances. Although the shaded crown and shaded background have darker reflectances, ignoring them in the area-weighted model is not serious when shrub cover is low and solar zenith angle is small. A submodel predicted the reflectance of the shrub crown as a function of the foliage reflectance and amount of plant material within the crown, and the background reflectance scattered or transmitted through canopy gaps (referred to as a soil—plant ‘spectral interaction’ term). One may be able to combine these two models to estimate both the fraction of vegetation cover and interception of PAR by green vegetation in a shrub savanna. (author)

  8. Availability of Japanese Government's supplemental texts on radiation reflecting the Fukushima Daiichi Nuclear Power Plant accident for elementary and secondary education from dental students' understanding

    International Nuclear Information System (INIS)

    Yoshida, Midori; Honda, Eiichi; Dashpuntsag, Oyunbat; Maeda, Naoki; Hosoki, Hidehiko; Sakama, Minoru; Tada, Toshiko

    2016-01-01

    Following the Fukushima Nuclear Power Plant accident, the Japanese government created two supplemental texts about radiation reflecting the accident for elementary, middle school, and high school students. These texts were made to explain radiation and consequently to obtain public consent for the continuation of the nuclear program. The present study aimed to evaluate the appropriateness of the content of the texts and to collect the basic data on the level of understanding necessary to improve radiation education. Lectures on radiology including nuclear energy and the Fukushima accident were given to 44 fourth-year dental students in 2013. The questionnaire was administered in 2014 when these students were in their sixth-year. The survey was also administered to 40 first-year students and 41 fourth-year students who hadn't any radiology lectures. Students rated their level of understanding of 50 phrases used in the texts on a four-point scale (understanding = 3, a little knowledge = 2, having heard = 1, no knowledge = 0). Questions on taking an advanced physics course in high school and means of learning about radiation in daily life were also asked. The level of understanding of phrases in the supplemental text for middle and high school students was significantly higher among sixth-year students (mean = 1.43) than among first-year (mean = 1.12) or fourth-year (mean = 0.93) students (p < 0.05). Overall, the level of understanding was low, with scores indicating that most students knew only a little. First-year students learning about radiation from television but four-year and six-year students learning about radiation from newspaper scored significantly higher (p < 0.05). It was concluded that radiation education should be improved by using visual material and preparing educators to teach the material for improving the public's understanding of radiation use—especially nuclear power generation because the phrases used in the supplementary

  9. Improved binary dragonfly optimization algorithm and wavelet packet based non-linear features for infant cry classification.

    Science.gov (United States)

    Hariharan, M; Sindhu, R; Vijean, Vikneswaran; Yazid, Haniza; Nadarajaw, Thiyagar; Yaacob, Sazali; Polat, Kemal

    2018-03-01

    Infant cry signal carries several levels of information about the reason for crying (hunger, pain, sleepiness and discomfort) or the pathological status (asphyxia, deaf, jaundice, premature condition and autism, etc.) of an infant and therefore suited for early diagnosis. In this work, combination of wavelet packet based features and Improved Binary Dragonfly Optimization based feature selection method was proposed to classify the different types of infant cry signals. Cry signals from 2 different databases were utilized. First database contains 507 cry samples of normal (N), 340 cry samples of asphyxia (A), 879 cry samples of deaf (D), 350 cry samples of hungry (H) and 192 cry samples of pain (P). Second database contains 513 cry samples of jaundice (J), 531 samples of premature (Prem) and 45 samples of normal (N). Wavelet packet transform based energy and non-linear entropies (496 features), Linear Predictive Coding (LPC) based cepstral features (56 features), Mel-frequency Cepstral Coefficients (MFCCs) were extracted (16 features). The combined feature set consists of 568 features. To overcome the curse of dimensionality issue, improved binary dragonfly optimization algorithm (IBDFO) was proposed to select the most salient attributes or features. Finally, Extreme Learning Machine (ELM) kernel classifier was used to classify the different types of infant cry signals using all the features and highly informative features as well. Several experiments of two-class and multi-class classification of cry signals were conducted. In binary or two-class experiments, maximum accuracy of 90.18% for H Vs P, 100% for A Vs N, 100% for D Vs N and 97.61% J Vs Prem was achieved using the features selected (only 204 features out of 568) by IBDFO. For the classification of multiple cry signals (multi-class problem), the selected features could differentiate between three classes (N, A & D) with the accuracy of 100% and seven classes with the accuracy of 97.62%. The experimental

  10. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  11. An Improved Measurement Method for the Strength of Radiation of Reflective Beam in an Industrial Optical Sensor Based on Laser Displacement Meter

    Directory of Open Access Journals (Sweden)

    Youngchul Bae

    2016-05-01

    Full Text Available An optical sensor such as a laser range finder (LRF or laser displacement meter (LDM uses reflected and returned laser beam from a target. The optical sensor has been mainly used to measure the distance between a launch position and the target. However, optical sensor based LRF and LDM have numerous and various errors such as statistical errors, drift errors, cyclic errors, alignment errors and slope errors. Among these errors, an alignment error that contains measurement error for the strength of radiation of returned laser beam from the target is the most serious error in industrial optical sensors. It is caused by the dependence of the measurement offset upon the strength of radiation of returned beam incident upon the focusing lens from the target. In this paper, in order to solve these problems, we propose a novel method for the measurement of the output of direct current (DC voltage that is proportional to the strength of radiation of returned laser beam in the received avalanche photo diode (APD circuit. We implemented a measuring circuit that is able to provide an exact measurement of reflected laser beam. By using the proposed method, we can measure the intensity or strength of radiation of laser beam in real time and with a high degree of precision.

  12. An Improved Measurement Method for the Strength of Radiation of Reflective Beam in an Industrial Optical Sensor Based on Laser Displacement Meter.

    Science.gov (United States)

    Bae, Youngchul

    2016-05-23

    An optical sensor such as a laser range finder (LRF) or laser displacement meter (LDM) uses reflected and returned laser beam from a target. The optical sensor has been mainly used to measure the distance between a launch position and the target. However, optical sensor based LRF and LDM have numerous and various errors such as statistical errors, drift errors, cyclic errors, alignment errors and slope errors. Among these errors, an alignment error that contains measurement error for the strength of radiation of returned laser beam from the target is the most serious error in industrial optical sensors. It is caused by the dependence of the measurement offset upon the strength of radiation of returned beam incident upon the focusing lens from the target. In this paper, in order to solve these problems, we propose a novel method for the measurement of the output of direct current (DC) voltage that is proportional to the strength of radiation of returned laser beam in the received avalanche photo diode (APD) circuit. We implemented a measuring circuit that is able to provide an exact measurement of reflected laser beam. By using the proposed method, we can measure the intensity or strength of radiation of laser beam in real time and with a high degree of precision.

  13. Non-radial radiative transfer in clese binaries. Application to the bolometric reflection effect in W UMa stars

    International Nuclear Information System (INIS)

    Pustylnik, I.

    1977-01-01

    In near-contact binary systems a significant portion of the total amount of the radiative energy is blocked between the facing hemispheres of two component stars. This circumstance combined with the lack of spherical symmetry of the radiation field may give rise to non-radial radiative transport. It is shown for a case of a spherical stellar atmosphere illuminated by a parallel beam of radiation that anisotropic scattering may be responsible for the non-radial component of the radiative flux. The effect of non-radial radiative transfer in close binaries would increase the total energy output observed at elongations at the expense of the radiative energy seen during conjunctions and would lead to colour changes qualitatively resembling those observed in many W UMa stars. Presumably it will be difficult to distinguish periodical light changes due to non-radial radiative transfer from those caused by distortions of the components or gravitational darkening. An order-of-magnitude estimate is made with the result that the bolometric amplitude of the non-radially scattered light probably does not exceed one per cent of the total luminosity of a binary system. (author)

  14. Relationship of transpiration and evapotranspiration to solar radiation and spectral reflectance in soybean [Glycine max] canopies: A simple method for remote sensing of canopy transpiration

    International Nuclear Information System (INIS)

    Choi, E.N.; Inoue, Y.

    2004-01-01

    Abstract The study investigated diurnal and seasonal dynamics of evapotranspiration (ET) and transpiration (Tr) in a soybean canopy, as well as the relationships among ET, Tr, solar radiation and remotely sensed spectral reflectance. The eddy covariance method (ECM) and stem heat balance method (SHBM) were used for independent measurement of ET and Tr, respectively. Micrometeorological, soil, and spectral reflectance data were acquired for the entire growing season. The instantaneous values of canopy-Tr estimated by SHBM and ET by ECM were well synchronized with each other, and both were strongly affected by the solar radiation. The daily values canopy-Tr increased rapidly with increasing leaf area index (LAI), and got closer to the ET even at a low value of LAI such as 1.5-2. The daily values of ET were moderately correlated with global solar radiation (Rs), and more closely with the potential evapotranspiration (ETp), estimated by the 'radiation method.' This fact supported the effectiveness of the simple radiation method in estimation of evapotranspiration. The ratio of Tr/ET as well as the ratio of ground heat flux (G) to Rs (G/Rs) was closely related to LAI, and LAI was a key variable in determining the energy partitioning to soil and vegetation. It was clearly shown that a remotely sensed vegetation index such as SAVI (soil adjusted vegetation index) was effective for estimating LAI, and further useful for directly estimating energy partitioning to soil and vegetation. The G and Tr/ET were both well estimated by the vegetation index. It was concluded that the combination of a simple radiation method with remotely sensed information can provide useful information on energy partitioning and Tr/ET in vegetation canopies

  15. High-performance flexible surface-enhanced Raman scattering substrates fabricated by depositing Ag nanoislands on the dragonfly wing

    Science.gov (United States)

    Wang, Yuhong; Wang, Mingli; Shen, Lin; Sun, Xin; Shi, Guochao; Ma, Wanli; Yan, Xiaoya

    2018-04-01

    Natural dragonfly wing (DW), as a template, was deposited on noble metal sliver (Ag) nanoislands by magnetron sputtering to fabricate a flexible, low-cost, large-scale and environment-friendly surface-enhanced Raman scattering (SERS) substrate (Ag/DW substrate). Generally, materials with regular surface nanostructures are chosen for the templates, the selection of our new material with irregular surface nanostructures for substrates provides a new idea for the preparation of high-performance SERS-active substrates and many biomimetic materials. The optimum sputtering time of metal Ag was also investigated at which the prepared SERS-active substrates revealed remarkable SERS activities to 4-aminothiophenol (4-ATP) and crystal violet (CV). Even more surprisingly, the Ag/DW substrate with such an irregular template had reached the enhancement factor (EF) of ∼1.05 × 105 and the detection limit of 10-10 M to 4-ATP. The 3D finite-different time-domain (3D-FDTD) simulation illustrated that the "hot spots" between neighbouring Ag nanoislands at the top of pillars played a most important role in generating electromagnetic (EM) enhancement and strengthening Raman signals.

  16. Availability of Japanese Government's supplemental texts on radiation reflecting the Fukushima Daiichi Nuclear Power Plant accident for elementary and secondary education from dental students' understanding.

    Science.gov (United States)

    Yoshida, Midori; Honda, Eiichi; Dashpuntsag, Oyunbat; Maeda, Naoki; Hosoki, Hidehiko; Sakama, Minoru; Tada, Toshiko

    2016-05-01

    Following the Fukushima Nuclear Power Plant accident, the Japanese government created two supplemental texts about radiation reflecting the accident for elementary, middle school, and high school students. These texts were made to explain radiation and consequently to obtain public consent for the continuation of the nuclear program. The present study aimed to evaluate the appropriateness of the content of the texts and to collect the basic data on the level of understanding necessary to improve radiation education. Lectures on radiology including nuclear energy and the Fukushima accident were given to 44 fourth-year dental students in 2013. The questionnaire was administered in 2014 when these students were in their sixth-year. The survey was also administered to 40 first-year students and 41 fourth-year students who hadn't any radiology lectures. Students rated their level of understanding of 50 phrases used in the texts on a four-point scale (understanding = 3, a little knowledge = 2, having heard = 1, no knowledge = 0). Questions on taking an advanced physics course in high school and means of learning about radiation in daily life were also asked. The level of understanding of phrases in the supplemental text for middle and high school students was significantly higher among sixth-year students (mean = 1.43) than among first-year (mean = 1.12) or fourth-year (mean = 0.93) students (p radiation from television but four-year and six-year students learning about radiation from newspaper scored significantly higher (p radiation education should be improved by using visual material and preparing educators to teach the material for improving the public's understanding of radiation use-especially nuclear power generation because the phrases used in the supplementary texts are very difficult for students to understand. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Reflectance Modeling

    Science.gov (United States)

    Smith, J. A.; Cooper, K.; Randolph, M.

    1984-01-01

    A classical description of the one dimensional radiative transfer treatment of vegetation canopies was completed and the results were tested against measured prairie (blue grama) and agricultural canopies (soybean). Phase functions are calculated in terms of directly measurable biophysical characteristics of the canopy medium. While the phase functions tend to exhibit backscattering anisotropy, their exact behavior is somewhat more complex and wavelength dependent. A Monte Carlo model was developed that treats soil surfaces with large periodic variations in three dimensions. A photon-ray tracing technology is used. Currently, the rough soil surface is described by analytic functions and appropriate geometric calculations performed. A bidirectional reflectance distribution function is calculated and, hence, available for other atmospheric or canopy reflectance models as a lower boundary condition. This technique is used together with an adding model to calculate several cases where Lambertian leaves possessing anisotropic leaf angle distributions yield non-Lambertian reflectance; similar behavior is exhibited for simulated soil surfaces.

  18. Measurement techniques and safety culture in radiation protection -reflections after 37 years of occupation with measuring instruments

    International Nuclear Information System (INIS)

    Maushart, R.

    1994-01-01

    Safety Culture in radiation use and radiation protection implies primarily knowledge and competence of the decision makers. As the measuring techniques are basic for practical radiation protection, only such person can be called competent who has sufficient expertise on measuring techniques, and is able to evaluate its application and results. Safety Culture also implies the readiness to expose errors, and to learn from them. ''Believing in infallibility'' excludes Safety Culture. Therefore, correctly applied measuring technique contributes to recognize weak points early. How far it is used consciously and actively to prevent undesirable developments and exceeding of limits, can be considered outright as a yardstick for a high-ranking safety culture. Safety Culture as a whole, however, needs more than more measuring techniques. It requires its own and adequate Measurement Culture, presupposing also motivation and determination to measure. Therefore, education, training, knowledge and consciousness of safety of the people who are responsible for measurements are decisive for successful radiation protection. (orig.) [de

  19. Characterization of atmospheric aerosols using Synchroton radiation total reflection X-ray fluorescence and Fe K-edge total reflection X-ray fluorescence-X-ray absorption near-edge structure

    Energy Technology Data Exchange (ETDEWEB)

    Fittschen, U.E.A. [Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany)], E-mail: ursula.fittschen@chemie.uni-hamburg.de; Meirer, F. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria)], E-mail: fmeirer@ati.ac.at; Streli, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria)], E-mail: streli@ati.ac.at; Wobrauschek, P. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria)], E-mail: wobi@ati.ac.at; Thiele, J. [Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany)], E-mail: Julian.Thiele@gmx.de; Falkenberg, G. [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22603 Hamburg (Germany)], E-mail: falkenbe@mail.desy.de; Pepponi, G. [ITC-irst, Via Sommarive 18, 38050 Povo (Trento) (Italy)], E-mail: pepponi@itc.it

    2008-12-15

    In this study a new procedure using Synchrotron total reflection X-ray fluorescence (SR-TXRF) to characterize elemental amounts in atmospheric aerosols down to particle sizes of 0.015 um is presented. The procedure was thoroughly evaluated regarding bounce off effects and blank values. Additionally the potential of total reflection X-ray fluorescence-X-ray absorption near edge structure (SR-TXRF-XANES) for speciation of FeII/III down to amounts of 34 pg in aerosols which were collected for 1 h is shown. The aerosols were collected in the city of Hamburg with a low pressure Berner impactor on Si carriers covered with silicone over time periods of 60 and 20 min each. The particles were collected in four and ten size fractions of 10.0-8.0 {mu}m, 8.0-2.0 {mu}m, 2.0-0.13 {mu}m 0.13-0.015 {mu}m (aerodynamic particle size) and 15-30 nm, 30-60 nm, 60-130 nm, 130-250 nm, 250-500 nm, 0.5-1 {mu}m, 1-2 {mu}m, 2-4 {mu}m, 4-8 {mu}m, 8-16 {mu}m. Prior to the sampling 'bounce off' effects on Silicone and Vaseline coated Si carriers were studied with total reflection X-ray fluorescence. According to the results silicone coated carriers were chosen for the analysis. Additionally, blank levels originating from the sampling device and the calibration procedure were studied. Blank levels of Fe corresponded to 1-10% of Fe in the aerosol samples. Blank levels stemming from the internal standard were found to be negligible. The results from the Synchroton radiation total reflection X-ray fluorescence analysis of the aerosols showed that 20 min of sampling time gave still enough sample material for elemental determination of most elements. For the determination of the oxidation state of Fe in the aerosols different Fe salts were prepared as a reference from suspensions in isopropanol. The results from the Fe K-edge Synchroton radiation total reflection X-ray fluorescence-X-ray absorption near-edge structure analysis of the aerosol samples showed that mainly Fe(III) was present in

  20. Characterization of atmospheric aerosols using Synchroton radiation total reflection X-ray fluorescence and Fe K-edge total reflection X-ray fluorescence-X-ray absorption near-edge structure

    International Nuclear Information System (INIS)

    Fittschen, U.E.A.; Meirer, F.; Streli, C.; Wobrauschek, P.; Thiele, J.; Falkenberg, G.; Pepponi, G.

    2008-01-01

    In this study a new procedure using Synchrotron total reflection X-ray fluorescence (SR-TXRF) to characterize elemental amounts in atmospheric aerosols down to particle sizes of 0.015 um is presented. The procedure was thoroughly evaluated regarding bounce off effects and blank values. Additionally the potential of total reflection X-ray fluorescence-X-ray absorption near edge structure (SR-TXRF-XANES) for speciation of FeII/III down to amounts of 34 pg in aerosols which were collected for 1 h is shown. The aerosols were collected in the city of Hamburg with a low pressure Berner impactor on Si carriers covered with silicone over time periods of 60 and 20 min each. The particles were collected in four and ten size fractions of 10.0-8.0 μm, 8.0-2.0 μm, 2.0-0.13 μm 0.13-0.015 μm (aerodynamic particle size) and 15-30 nm, 30-60 nm, 60-130 nm, 130-250 nm, 250-500 nm, 0.5-1 μm, 1-2 μm, 2-4 μm, 4-8 μm, 8-16 μm. Prior to the sampling 'bounce off' effects on Silicone and Vaseline coated Si carriers were studied with total reflection X-ray fluorescence. According to the results silicone coated carriers were chosen for the analysis. Additionally, blank levels originating from the sampling device and the calibration procedure were studied. Blank levels of Fe corresponded to 1-10% of Fe in the aerosol samples. Blank levels stemming from the internal standard were found to be negligible. The results from the Synchroton radiation total reflection X-ray fluorescence analysis of the aerosols showed that 20 min of sampling time gave still enough sample material for elemental determination of most elements. For the determination of the oxidation state of Fe in the aerosols different Fe salts were prepared as a reference from suspensions in isopropanol. The results from the Fe K-edge Synchroton radiation total reflection X-ray fluorescence-X-ray absorption near-edge structure analysis of the aerosol samples showed that mainly Fe(III) was present in all particle size fractions

  1. Study on temperature measurement of gas turbine blade based on analysis of error caused by the reflected radiation and emission angle

    Science.gov (United States)

    Li, Dong; Feng, Chi; Gao, Shan; Chen, Liwei; Daniel, Ketui

    2018-06-01

    Accurate measurement of gas turbine blade temperature is of great significance as far as blade health monitoring is concerned. An important method for measuring this temperature is the use of a radiation pyrometer. In this research, error of the pyrometer caused by reflected radiation from the surfaces surrounding the target and the emission angle of the target was analyzed. Important parameters for this analysis were the view factor between interacting surfaces, spectral directional emissivity, pyrometer operating wavelength and the surface temperature distribution on the blades and the vanes. The interacting surface of the rotor blade and the vane models used were discretized using triangular surface elements from which contour integral was used to calculate the view factor between the surface elements. Spectral directional emissivities were obtained from an experimental setup of Ni based alloy samples. A pyrometer operating wavelength of 1.6 μm was chosen. Computational fluid dynamics software was used to simulate the temperature distribution of the rotor blade and the guide vane based on the actual gas turbine input parameters. Results obtained in this analysis show that temperature error introduced by reflected radiation and emission angle ranges from  ‑23 K to 49 K.

  2. How do air ions reflect variations in ionising radiation in the lower atmosphere in a boreal forest?

    Directory of Open Access Journals (Sweden)

    X. Chen

    2016-11-01

    Full Text Available Most of the ion production in the atmosphere is attributed to ionising radiation. In the lower atmosphere, ionising radiation consists mainly of the decay emissions of radon and its progeny, gamma radiation of the terrestrial origin as well as photons and elementary particles of cosmic radiation. These types of radiation produce ion pairs via the ionisation of nitrogen and oxygen as well as trace species in the atmosphere, the rate of which is defined as the ionising capacity. Larger air ions are produced out of the initial charge carriers by processes such as clustering or attachment to pre-existing aerosol particles. This study aimed (1 to identify the key factors responsible for the variability in ionising radiation and in the observed air ion concentrations, (2 to reveal the linkage between them and (3 to provide an in-depth analysis into the effects of ionising radiation on air ion formation, based on measurement data collected during 2003–2006 from a boreal forest site in southern Finland. In general, gamma radiation dominated the ion production in the lower atmosphere. Variations in the ionising capacity came from mixing layer dynamics, soil type and moisture content, meteorological conditions, long-distance transportation, snow cover attenuation and precipitation. Slightly similar diurnal patterns to variations in the ionising capacity were observed in air ion concentrations of the cluster size (0.8–1.7 nm in mobility diameters. However, features observed in the 0.8–1 nm ion concentration were in good connection to variations of the ionising capacity. Further, by carefully constraining perturbing variables, a strong dependency of the cluster ion concentration on the ionising capacity was identified, proving the functionality of ionising radiation in air ion production in the lower atmosphere. This relationship, however, was only clearly observed on new particle formation (NPF days, possibly indicating that charges after

  3. Dragonfly : an implementation of the expand–maximize–compress algorithm for single-particle imaging

    OpenAIRE

    Ayyer, Kartik; Lan, Ti-Yen; Elser, Veit; Loh, N. Duane

    2016-01-01

    Single-particle imaging (SPI) with X-ray free-electron lasers has the potential to change fundamentally how biomacromolecules are imaged. The structure would be derived from millions of diffraction patterns, each from a different copy of the macromolecule before it is torn apart by radiation damage. The challenges posed by the resultant data stream are staggering: millions of incomplete, noisy and un-oriented patterns have to be computationally assembled into a three-dimensional intensity map...

  4. Multielement determination in river-water of Sepetiba Bay tributaries (Brazil) by total reflection X-ray fluorescence using synchrotron radiation

    International Nuclear Information System (INIS)

    Costa, A.C.M.; Castro, C.R.F.; Lopes, R.T.; Anjos, M.J.; Rio de Janeiro State Univ.

    2006-01-01

    Trace elements were determined in the surface waters of tributaries of the Sepetiba Bay, Brazil (Piraque, Ita, Sao Francisco, Guarda, Guandu Mirim, Vala do Sangue and Engenho Novo rivers) by total reflection X-ray fluorescence using synchrotron radiation (SRTXRF). Eighteen trace elements could be determined in the dissolved and the suspended particulate phases: Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr and Pb. The elemental concentration values were compared to the values recommended by the Brazilian legislation. (author)

  5. Long-term genetic monitoring of a riverine dragonfly, Orthetrum coerulescens (Odonata: Libellulidae]: Direct anthropogenic impact versus climate change effects.

    Science.gov (United States)

    Herzog, Rebecca; Hadrys, Heike

    2017-01-01

    Modern conservationists call for long term genetic monitoring datasets to evaluate and understand the impact of human activities on natural ecosystems and species on a global but also local scale. However, long-term monitoring datasets are still rare but in high demand to correctly identify, evaluate and respond to environmental changes. In the presented study, a population of the riverine dragonfly, Orthetrum coerulescens (Odonata: Libellulidae), was monitored over a time period from 1989 to 2013. Study site was an artificial irrigation ditch in one of the last European stone steppes and "nature heritage", the Crau in Southern France. This artificial riverine habitat has an unusual high diversity of odonate species, prominent indicators for evaluating freshwater habitats. A clearing of the canal and destruction of the bank vegetation in 1996 was assumed to have great negative impact on the odonate larval and adult populations. Two mitochondrial markers (CO1 & ND1) and a panel of nuclear microsatellite loci were used to assess the genetic diversity. Over time they revealed a dramatic decline in diversity parameters between the years 2004 and 2007, however not between 1996 and 1997. From 2007 onwards the population shows a stabilizing trend but has not reached the amount of genetic variation found at the beginning of this survey. This decline cannot be referred to the clearing of the canal or any other direct anthropogenic impact. Instead, it is most likely that the populations' decay was due to by extreme weather conditions during the specific years. A severe drought was recorded for the summer months of these years, leading to reduced water levels in the canal causing also other water parameters to change, and therefore impacting temperature sensitive riverine habitat specialists like the O. coerulescens in a significant way. The data provide important insights into population genetic dynamics and metrics not always congruent with traditional monitoring data (e

  6. Datura metel-synthesized silver nanoparticles magnify predation of dragonfly nymphs against the malaria vector Anopheles stephensi.

    Science.gov (United States)

    Murugan, Kadarkarai; Dinesh, Devakumar; Kumar, Prabhu Jenil; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Madhiyazhagan, Pari; Suresh, Udaiyan; Nicoletti, Marcello; Alarfaj, Abdullah A; Munusamy, Murugan A; Higuchi, Akon; Mehlhorn, Heinz; Benelli, Giovanni

    2015-12-01

    Malaria is a life-threatening disease caused by parasites transmitted to people and animals through the bites of infected mosquitoes. The employ of synthetic insecticides to control Anopheles populations leads to high operational costs, non-target effects, and induced resistance. Recently, plant-borne compounds have been proposed for efficient and rapid extracellular synthesis of mosquitocidal nanoparticles. However, their impact against predators of mosquito larvae has been poorly studied. In this study, we synthesized silver nanoparticles (AgNPs) using the Datura metel leaf extract as reducing and stabilizing agent. The biosynthesis of AgNPs was confirmed analyzing the excitation of surface plasmon resonance using ultraviolet-visible (UV-vis) spectroscopy. Scanning electron microscopy (SEM) showed the clustered and irregular shapes of AgNPs, with a mean size of 40-60 nm. The presence of silver was determined by energy-dispersive X-ray (EDX) spectroscopy. Fourier transform infrared (FTIR) spectroscopy analysis investigated the identity of secondary metabolites, which may be acting as AgNP capping agents. In laboratory, LC50 of D. metel extract against Anopheles stephensi ranged from 34.693 ppm (I instar larvae) to 81.500 ppm (pupae). LC50 of AgNP ranged from 2.969 ppm (I instar larvae) to 6.755 ppm (pupae). Under standard laboratory conditions, the predation efficiency of Anax immaculifrons nymphs after 24 h was 75.5 % (II instar larvae) and 53.5 % (III instar larvae). In AgNP-contaminated environment, predation rates were boosted to 95.5 and 78 %, respectively. Our results documented that D. metel-synthesized AgNP might be employed at rather low doses to reduce larval populations of malaria vectors, without detrimental effects on behavioral traits of young instars of the dragonfly Anax immaculifrons.

  7. Reflecting reflection in supervision

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    associated with reflection and an exploration of alternative conceptions that view reflection within the context of settings which have a more group- and team-based orientation. Drawing on an action research project on health care supervision, the paper questions whether we should reject earlier views...... of reflection, rehabilitate them in order to capture broader connotations or move to new ways of regarding reflection that are more in keeping with not only reflective but also emotive, normative and formative views on supervision. The paper presents a critical perspective on supervision that challenge...... the current reflective paradigm I supervision and relate this to emotive, normative and formative views supervision. The paper is relevant for Nordic educational research into the supervision and guidance...

  8. Reflective Packaging

    Science.gov (United States)

    1994-01-01

    The aluminized polymer film used in spacecraft as a radiation barrier to protect both astronauts and delicate instruments has led to a number of spinoff applications. Among them are aluminized shipping bags, food cart covers and medical bags. Radiant Technologies purchases component materials and assembles a barrier made of layers of aluminized foil. The packaging reflects outside heat away from the product inside the container. The company is developing new aluminized lines, express mailers, large shipping bags, gel packs and insulated panels for the building industry.

  9. Radiation protection actions at Swedish nuclear power plants 1994-2002 and some reflections about the near future; Straalskydd vid svenska kaernkraftverk under perioden 1994-2002, samt reflexioner om kommande utveckling

    Energy Technology Data Exchange (ETDEWEB)

    Erixon, Stig; Godaas, Tommy; Hofvander, Peter; Lund, Ingmar; Malmqvist, Lars; Thimgren, Ingela; Oelander-Guer, Hanna

    2003-12-01

    This report provides a summary of radiation protection experiences over the years 1994-2002 in the Swedish nuclear power industry. Actions to reduce radiation levels in reactor systems, occupational exposure results and some reflections about the near future are presented.

  10. The effect of radiation-thermal treatment on the physicochemical properties of the Ni-Mo/Al2O3 hydrotreatment catalyst. II. UV-Vis diffuse reflectance spectra of surface compounds after irradiation

    International Nuclear Information System (INIS)

    Solovetskii, Yu.I.; Miroshinichenko, I.I.; Lunin, V.V.

    1993-01-01

    Radiation-thermal damage of the surface and the active metal phases of hydrodesulfurization Ni-Mo/Al 2 O 3 catalysts by a fast electron beam of up to 2.0 MeV energy was studied. UV-Vis diffuse reflectance spectra of the industrial and model coked systems after radiation-thermal treatment were measured. 14 refs., 2 figs

  11. The Development of Radiation hardened tele-robot system - Development of artificial force reflection control for teleoperated mobile robots

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Jang; Hong, Sun Gi; Kang, Young Hoon; Kim, Min Soeng [Korea Advanced Institute of Science and Technology, Taejon (Korea)

    1999-04-01

    One of the most important issues in teleoperation is to provide the sense of telepresence so as to conduct the task more reliably. In particular, teleoperated mobile robots are needed to have some kinds of backup system when the operator is blind for remote situation owing to the failure of vision system. In the first year, the idea of artificial force reflection was researched to enhance the reliability of operation when the mobile robot travels on the plain ground. In the second year, we extend previous results to help the teleoperator even when the robot climbs stairs. Finally, we apply the developed control algorithms to real experiments. The artificial force reflection method has two modes; traveling on the plain ground and climbing stairs. When traveling on the plain ground, the force information is artificially generated by using the range data from the environment while generating the impulse force when climbing stairs. To verify the validity of our algorithm, we develop the simulator which consists of the joystick and the visual display system. Through some experiments using this system, we confirm the validity and effectiveness of our new idea of artificial force reflection in the teleoperated mobile robot. 11 refs., 30 figs. (Author)

  12. Using Neural Networks to Improve the Performance of Radiative Transfer Modeling Used for Geometry Dependent Surface Lambertian-Equivalent Reflectivity Calculations

    Science.gov (United States)

    Fasnacht, Zachary; Qin, Wenhan; Haffner, David P.; Loyola, Diego; Joiner, Joanna; Krotkov, Nickolay; Vasilkov, Alexander; Spurr, Robert

    2017-01-01

    Surface Lambertian-equivalent reflectivity (LER) is important for trace gas retrievals in the direct calculation of cloud fractions and indirect calculation of the air mass factor. Current trace gas retrievals use climatological surface LER's. Surface properties that impact the bidirectional reflectance distribution function (BRDF) as well as varying satellite viewing geometry can be important for retrieval of trace gases. Geometry Dependent LER (GLER) captures these effects with its calculation of sun normalized radiances (I/F) and can be used in current LER algorithms (Vasilkov et al. 2016). Pixel by pixel radiative transfer calculations are computationally expensive for large datasets. Modern satellite missions such as the Tropospheric Monitoring Instrument (TROPOMI) produce very large datasets as they take measurements at much higher spatial and spectral resolutions. Look up table (LUT) interpolation improves the speed of radiative transfer calculations but complexity increases for non-linear functions. Neural networks perform fast calculations and can accurately predict both non-linear and linear functions with little effort.

  13. FT-IR reflection spectra of single crystals: resolving phonons of different symmetry without using polarised radiation

    Directory of Open Access Journals (Sweden)

    METODIJA NAJDOSKI

    2000-07-01

    Full Text Available Fourier-transform infrared (FT-IR reflection spectra, asquired at nearnormal incidence, were recorded from single crystals belonging to six crystal systems: CsCr(SO42.12H2O (alum, cubic, K2CuCl2·2H2O (Mitscherlichite, tetragonal, CaCO3 (calcite, hexagonal, KHSO4 (mercallite, orthorhombic, CaSO4·2H2O (gypsum, monoclinic and CuSO4·5H2O (chalcantite, triclinic. The acquired IR reflection spectra were further transformed into absorption spectra, employing the Kramers-Kronig transformation. Except for the cubic alums, the spectra strongly depend on the crystal face from which they were recorded; this is a consequence of anisotropy. Phonons of a given symmetry (E-species, in tetragonal/hexagonal and B-species, in monoclinic crystals may be resolved without using a polariser. The spectrum may be simplified in the case of an orthorhombic crystal, as well. The longitudinal-optical (LO and transversal-optical (TO mode frequencies were calculated in the case of optically isotropic and the simplified spectra of optically uniaxial crystals.

  14. Healthy as a trout – as delicate as a dragon-fly

    Directory of Open Access Journals (Sweden)

    Heesters, Ann Munro

    2014-10-01

    Full Text Available Rehabilitation hospitals provide a striking contrast between young, fit and largely able-bodied staff and patients who have experienced significant, often sudden, life-changing events. Bridging the gap between these worlds is not easy, but it can also be difficult to reconcile the values that the patients held before injury or illness with those that have begun to emerge on the road to recovery. Those working in rehabilitation medicine often endorse a process model of consent because they understand that patients with fresh injuries may need time for their values to adapt to their new lives. Despite this understanding, it can be a challenge to understand how best to respect patient autonomy whilst helping those same patients to appreciate some of the limits on their abilities. Drafting the following personal narrative, drawn from my own experience as a healthcare ethicist and reluctant patient, gave me greater insight into these perplexities. This reflection explores my changing approach to my professional practice – and especially my view of patient autonomy – in light of my own experience with post-partum depression.

  15. RESEARCH OF THE ENTRANCE ANGLE EFFECT ON THE REFLECTANCE SPECTRA OF THE STAINLESS STEEL SURFACE OXIDIZED BY PULSED LASER RADIATION

    Directory of Open Access Journals (Sweden)

    V. P. Veiko

    2016-05-01

    Full Text Available Subject of Research.Oxide films on the metal surfaces can be obtained both by surface-uniform infrared heating and local laser treatment e.g. by sequence of nanosecond laser pulses. Due to interference in created films the coloration of treated area is observed. The present work shows the results of spectrophotometric measurements for various light entrance angles in the range of 10-60°. Method. AISI 304 stainless steel plates were oxidized by two methods: in muffle furnace FM - 10 (Т= 500-600° С, t = 5-7 min. and at line-by-line scanning by sequence of nanosecond laser pulses (λ = 1.06 μm, τ =100 ns, r = 25 μm,q=2.91∙107 W/cm2, Nx = 30, Ny = 1. Surface research in optical resolution was realized by Carl Zeiss Axio Imager A1M. Reflectance spectra were obtained with spectrophotometer Lambda Perkin 1050 with integrating sphere at different fixed light incidence angles. Topographic features were detected by scanning probe microscopy investigation with NanoEducator equipment. Main Results. The quantitative surface geometry characteristics of AISI 304 stainless steel patterns treated by different methods are obtained. It was found that the increase of light entrance angle has no influence on the form of reflection coefficient dependence from a wavelength, but a blue-shift occurs especially for the case of laser treatment. This difference can be caused by surface topology formed by laser heating and variety of oxide film thickness. This effect results in more significant change in observed sample color for laser treatment then for infrared heating. Practical Relevance. The results obtained in the present work can be used to implement a new element of product protection against forgery with the product marking.

  16. New calculation of derived limits for the 1960 radiation protection guides reflecting updated models for dosimetry and biological transport

    International Nuclear Information System (INIS)

    Eckerman, K.F.; Watson, S.B.; Nelson, C.B.; Nelson, D.R.; Richardson, A.C.B.; Sullivan, R.E.

    1984-12-01

    This report presents revised values for the radioactivity concentration guides (RCGs), based on the 1960 primary radiation protection guides (RPGs) for occupational exposure (FRC 1960) and for underground uranium miners (EPA 1971a) using the updated dosimetric models developed to prepare ICRP Publication 30. Unlike the derived quantities presented in Publication 30, which are based on limitation of the weighted sum of doses to all irradiated tissues, these RCGs are based on the ''critical organ'' approach of the 1960 guidance, which was a single limit for the most critically irradiated organ or tissue. This report provides revised guides for the 1960 Federal guidance which are consistent with current dosimetric relationships. 2 figs., 4 tabs

  17. Biomonitoring of environmental pollution using growth tree rings of Tipuana tipu: Quantification by synchrotron radiation total reflection X-ray fluorescence

    Science.gov (United States)

    Geraldo, S. M.; Canteras, F. B.; Moreira, S.

    2014-02-01

    Currently, many studies use the bioindicators to qualitatively and/or quantitatively measure pollution. The analyses of tree growth rings represent one such bioindicator as changes in the environment are often recorded as impressions in the wood. The main objective of the present study is to examine the growth rings of Tipuana tipu - a member of the Leguminosae family that is native to Argentina and Bolivia and was introduced in Brazil as an ornamental plant - for potentially toxic elements. T. tipu is one of the most common trees in the urban landscape of Sao Paulo city and would provide an accurate reflection of environment changes. Tree ring samples previously dated using Synchrotron Radiation Total Reflection X-ray Fluorescence were collected from strategic locations in Sao Paulo. These locations include Piracicaba (SP) that has little access and small flow traffic and the campus of the University of São Paulo. Some trace elements present concentrations higher than considered as normal in some periods. In São Paulo city, samples collected from the campus of University of São Paulo (Butantã), showed the highest toxicity, with concentrations above the tolerable limit for the elements: Cr, Cu, and Pb. For the samples collected in Piracicaba city, one sample presented highest concentrations for the majority of the elements when compared to the other four samples collected at the same place, exceeding the toxicity limits for: Cr, Ni, Cu, and Pb.

  18. Stress measurements by multi-reflection grazing-incidence X-ray diffraction method (MGIXD) using different radiation wavelengths and different incident angles

    International Nuclear Information System (INIS)

    Marciszko, Marianna; Baczmański, Andrzej; Braham, Chedly; Wróbel, Mirosław; Wroński, Sebastian; Cios, Grzegorz

    2017-01-01

    The presented study introduces the development of the multi-reflection grazing-incidence X-ray diffraction method (MGIXD) for residual stress determination. The proposed new methodology is aimed at obtaining more reliable experimental data and increasing the depth of non-destructive stress determination below the sample surface. To verify proposed method measurements were performed on a classical X-ray diffractometer (Cu Kα radiation) and using synchrotron radiation (three different wavelengths: λ = 1.2527 Å, λ = 1.5419 Å and λ = 1.7512 Å). The Al2017 alloy subjected to three different surface treatments was investigated in this study. The obtained results showed that the proposed development of MGIXD method, in which not only different incident angles but also different wavelengths of X-ray are used, can be successfully applied for residual stress determination, especially when stress gradients are present in the sample.

  19. Evaluation of heavy metals in atmospheric emissions from automotive industry by total reflection X-ray fluorescence with synchrotron radiation

    International Nuclear Information System (INIS)

    Moreira, Silvana; Weber Neto, Jose; Vives, Ana Elisa Sirito de

    2009-01-01

    This study had as goal to determine heavy metals and other elements (Ba, Br, Ca, Pb, Cl, Cr, Sr, Fe, Mn, Ni, K, Si, Ti and Zn) in atmospheric pollutants generated by an automotive industry located in the city of Engenheiro Coelho, state of Sao Paulo, Brazil. The sampling and sample preparation procedures were based on methods established by the Company of Sanitation and Technology (CETESB L9.234) and also by the Environmental Protection Agency (EPA - Method 29). The analysis was performed at XRF Beamline (D09B-XRF) in the Synchrotron Light Source Laboratory (Campinas/SP). A white beam of synchrotron radiation was used for sample and standard excitation which were irradiated by 100 seconds. For X-ray lines detection, a Ge (HP) detector with 150 eV of resolution at 5.9 keV was employed. For zinc, iron, barium, calcium and potassium, the values obtained were in the range of 30 mg/Nm 3 and, for other elements, the concentrations were approximately 1 mg/Nm 3 . The sum of As, Be, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Sn, Te and Zn concentration was compared with the limits established by CONAMA 264/1999 and SEMA 041/2002 resolutions (7.0 mg/Nm 3 ) and it was observed that, for all samples, sums are higher than the permissive value mainly due to the high concentration of zinc. Detection limits for SR-TXRF technique were 0.10 μg/Nm 3 for Pb and 0.02 μg/Nm 3 for Zn. (author)

  20. Evaluation of heavy metals in atmospheric emissions from automotive industry by total reflection X-ray fluorescence with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana; Weber Neto, Jose, E-mail: silvana@fec.unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo. Dept. de Saneamento e Ambiente; Vives, Ana Elisa Sirito de, E-mail: aesvives@unimep.b [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo

    2009-07-01

    This study had as goal to determine heavy metals and other elements (Ba, Br, Ca, Pb, Cl, Cr, Sr, Fe, Mn, Ni, K, Si, Ti and Zn) in atmospheric pollutants generated by an automotive industry located in the city of Engenheiro Coelho, state of Sao Paulo, Brazil. The sampling and sample preparation procedures were based on methods established by the Company of Sanitation and Technology (CETESB L9.234) and also by the Environmental Protection Agency (EPA - Method 29). The analysis was performed at XRF Beamline (D09B-XRF) in the Synchrotron Light Source Laboratory (Campinas/SP). A white beam of synchrotron radiation was used for sample and standard excitation which were irradiated by 100 seconds. For X-ray lines detection, a Ge (HP) detector with 150 eV of resolution at 5.9 keV was employed. For zinc, iron, barium, calcium and potassium, the values obtained were in the range of 30 mg/Nm{sup 3} and, for other elements, the concentrations were approximately 1 mg/Nm{sup 3}. The sum of As, Be, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Sn, Te and Zn concentration was compared with the limits established by CONAMA 264/1999 and SEMA 041/2002 resolutions (7.0 mg/Nm{sup 3}) and it was observed that, for all samples, sums are higher than the permissive value mainly due to the high concentration of zinc. Detection limits for SR-TXRF technique were 0.10 mug/Nm{sup 3} for Pb and 0.02 mug/Nm{sup 3} for Zn. (author)

  1. Radiations

    International Nuclear Information System (INIS)

    Pujol Mora, J.

    1999-01-01

    The exposition to ionizing radiations is a constant fact in the life of the human being and its utilization as diagnostic and therapeutic method is generalized. However, it is notorious how as years go on, the fear to the ionizing radiation seems to persist too, and this fact is not limited to the common individual, but to the technical personnel and professional personnel that labors with them same. (S. Grainger) [es

  2. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  3. Radiation

    International Nuclear Information System (INIS)

    Winther, J.F.; Ulbak, K.; Dreyer, L.; Pukkala, E.; Oesterlind, A.

    1997-01-01

    Exposure to solar and ionizing radiation increases the risk for cancer in humans. Some 5% of solar radiation is within the ultraviolet spectrum and may cause both malignant melanoma and non-melanocytic skin cancer; the latter is regarded as a benign disease and is accordingly not included in our estimation of avoidable cancers. Under the assumption that the rate of occurrence of malignant melanoma of the buttocks of both men and women and of the scalp of women would apply to all parts of the body in people completely unexposed to solar radiation, it was estimated that approximately 95% of all malignant melanomas arising in the Nordic populations around the year 2000 will be due to exposure to natural ultraviolet radiation, equivalent to an annual number of about 4700 cases, with 2100 in men and 2600 in women, or some 4% of all cancers notified. Exposure to ionizing radiation in the Nordic countries occurs at an average effective dose per capita per year of about 3 mSv (Iceland, 1.1 mSv) from natural sources, and about 1 mSv from man-made sources. While the natural sources are primarily radon in indoor air, natural radionuclides in food, cosmic radiation and gamma radiation from soil and building materials, the man-made sources are dominated by the diagnostic and therapeutic use of ionizing radiation. On the basis of measured levels of radon in Nordic dwellings and associated risk estimates for lung cancer derived from well-conducted epidemiological studies, we estimated that about 180 cases of lung cancer (1% of all lung cancer cases) per year could be avoided in the Nordic countries around the year 2000 if indoor exposure to radon were eliminated, and that an additional 720 cases (6%) could be avoided annually if either radon or tobacco smoking were eliminated. Similarly, it was estimated that the exposure of the Nordic populations to natural sources of ionizing radiation other than radon and to medical sources will each give rise to an annual total of 2120

  4. Effect of the Absorbed Photosynthetically Active Radiation Estimation Error on Net Primary Production Estimation - A Study with MODIS FPAR and TOMS Ultraviolet Reflective Products

    International Nuclear Information System (INIS)

    Kobayashi, H.; Matsunaga, T.; Hoyano, A.

    2002-01-01

    Absorbed photosynthetically active radiation (APAR), which is defined as downward solar radiation in 400-700 nm absorbed by vegetation, is one of the significant variables for Net Primary Production (NPP) estimation from satellite data. Toward the reduction of the uncertainties in the global NPP estimation, it is necessary to clarify the APAR accuracy. In this paper, first we proposed the improved PAR estimation method based on Eck and Dye's method in which the ultraviolet (UV) reflectivity data derived from Total Ozone Mapping Spectrometer (TOMS) at the top of atmosphere were used for clouds transmittance estimation. The proposed method considered the variable effects of land surface UV reflectivity on the satellite-observed UV data. Monthly mean PAR comparisons between satellite-derived and ground-based data at various meteorological stations in Japan indicated that the improved PAR estimation method reduced the bias errors in the summer season. Assuming the relative error of the fraction of PAR (FPAR) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) to be 10%, we estimated APAR relative errors to be 10-15%. Annual NPP is calculated using APAR derived from MODIS/ FPAR and the improved PAR estimation method. It is shown that random and bias errors of annual NPP in a 1 km resolution pixel are less than 4% and 6% respectively. The APAR bias errors due to the PAR bias errors also affect the estimated total NPP. We estimated the most probable total annual NPP in Japan by subtracting the bias PAR errors. It amounts about 248 MtC/yr. Using the improved PAR estimation method, and Eck and Dye's method, total annual NPP is 4% and 9% difference from most probable value respectively. The previous intercomparison study among using fifteen NPP models4) showed that global NPP estimations among NPP models are 44.4-66.3 GtC/yr (coefficient of variation = 14%). Hence we conclude that the NPP estimation uncertainty due to APAR estimation error is small

  5. When rare is just a matter of sampling: unexpected dominance of clubtail dragonflies (Odonata, Gomphidae through different collecting methods at Parque Nacional da Serra do Cipó, Minas Gerais State, Brazil

    Directory of Open Access Journals (Sweden)

    Marcus Vinícius Oliveira de Almeida

    2013-12-01

    Full Text Available When rare is just a matter of sampling: Unexpected dominance of clubtail dragonflies (Odonata, Gomphidae through different collecting methods at Parque Nacional da Serra do Cipó, Minas Gerais State, Brazil. Capture of dragonfly adults during two short expeditions to Parque Nacional da Serra do Cipó, Minas Gerais State, using three distinct collecting methodsaerial nets, Malaise and light sheet trapsis reported. The results are outstanding due the high number of species of Gomphidae (7 out of 26 Odonata species, including a new species of Cyanogomphus Selys, 1873, obtained by two non-traditional collecting methods. Because active collecting with aerial nets is the standard approach for dragonfly inventories, we discuss some aspects of the use of traps, comparing our results with those in the literature, suggesting they should be used as complementary methods in faunistic studies. Furthermore, Zonophora campanulata annulata Belle, 1983 is recorded for the first time from Minas Gerais State and taxonomic notes about Phyllogomphoides regularis (Selys, 1873 and Progomphus complicatus Selys, 1854 are also given.

  6. Monitoring of the environmental pollution by trace element analysis in tree-rings using synchrotron radiation total reflection X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Sirito de Vives, Ana Elisa [School of Civil Engineering, Architecture and Urban Design Methodist University of Piracicaba, Rodovia Santa Barbara D' Oeste/Iracemapolis, km 01, 13450-000 Santa Barbara D' Oeste, SP (Brazil)]. E-mail: aesvives@unimep.br; Moreira, Silvana [State University of Campinas - UNICAMP/FEC (Brazil); Brienza, Sandra Maria Boscolo [School of Civil Engineering, Architecture and Urban Design Methodist University of Piracicaba, Rodovia Santa Barbara D' Oeste/Iracemapolis, km 01, 13450-000 Santa Barbara D' Oeste, SP (Brazil); Silva Medeiros, Jean Gabriel [University of Sao Paulo - USP/ ESALQ (Brazil); Tomazello Filho, Mario Tomazello [University of Sao Paulo - USP/ ESALQ (Brazil); Araujo Domingues Zucchi, Orgheda Luiza [University of Sao Paulo - USP/FCFRP (Brazil); Nascimento Filho, Virgilio Franco do [University of Sao Paulo - USP/CENA (Brazil)

    2006-11-15

    This paper aims to study the environmental pollution in the tree development, in order to evaluate its use as bioindicator in urban and country sides. The sample collection was carried out in Piracicaba city, Sao Paulo State, which presents high level of environmental contamination in water, soil and air, due to industrial activities, vehicles combustion, sugar-cane leaves burning in the harvesting, etc. The species Caesalpinia peltophoroides ('Sibipiruna') was selected because it is widely used in urban forestation. Synchrotron Radiation Total Reflection X-ray Fluorescence technique (SR-TXRF) was employed to identify and quantify the elements and metals of nutritional and toxicological importance in the wood samples. The analysis was performed in the Brazilian Synchrotron Light Source Laboratory, using a white beam for excitation and a Si(Li) detector for X-ray detection. In several samples, P, K, Ca, Ti, Fe, Sr, Ba and Pb were quantified. The K/Ca, K/P and Pb/Ca ratios were found to decrease towards the bark.

  7. Quantification of potentially toxic elements in sewage and sludge from treatment plants in the cities of Campinas and Jaguariuna using synchrotron radiation total reflection X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Luciana Carla Ferreira de; Canteras, Felippe Benavente; Moreira, Silvana, E-mail: silvana@fec.unicamp.br, E-mail: felippe.canteras@gmail.com, E-mail: lucarla24@gmail.com [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Inst. Politecnico. Dept. de Saneamento e Ambiente

    2013-07-01

    The rapid urban and industrial development in last decades has brought as one of the consequences, changes in the environment. The lack of planning of city growth is, today, one of the major causes of water pollution including residential, industrial, agricultural, and hospital waste. The metals contamination is a major problem, causing serious changes to the environment, causing harm to human health. The sludge generated at sewage treatment plants, is an important source of nutrients and organic matter, and therefore it can also be reused mainly for agricultural use, since contaminants are removed. The cities of Campinas and Jaguariuna are inserted in the Campinas Metropolitan Region (CMR), one of the most dynamic regions in the Brazilian economy. Therefore, to study the anthropogenic influences of the cities, evaluated the quality of raw and treated effluent and the sludge generated in sewage treatment plants, especially with regard to heavy metals. Measurements of metals were performed by Synchrotron Radiation Total Reflection X-ray Fluorescence. For treated effluent data were compared to CONAMA 357 law and Cr, Mn, Fe, Ni, Cu, Zn, Ba and Pb showed concentrations in according with the law. To reuse in agriculture the contents were compared to the limits defined by CETESB and some elements had concentrations above to the permitted preventing its reuse. For sludge, Cr, Ni, Cu, Zn, Ba and Pb, in the two treatment plants studied, the concentrations were lower than the maximum permissible values established by CONAMA 375 law allowing the sludge application sludge on agricultural land. (author)

  8. Monitoring of the environmental pollution by trace element analysis in tree-rings using synchrotron radiation total reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Sirito de Vives, Ana Elisa; Moreira, Silvana; Brienza, Sandra Maria Boscolo; Silva Medeiros, Jean Gabriel; Tomazello Filho, Mario Tomazello; Araujo Domingues Zucchi, Orgheda Luiza; Nascimento Filho, Virgilio Franco do

    2006-01-01

    This paper aims to study the environmental pollution in the tree development, in order to evaluate its use as bioindicator in urban and country sides. The sample collection was carried out in Piracicaba city, Sao Paulo State, which presents high level of environmental contamination in water, soil and air, due to industrial activities, vehicles combustion, sugar-cane leaves burning in the harvesting, etc. The species Caesalpinia peltophoroides ('Sibipiruna') was selected because it is widely used in urban forestation. Synchrotron Radiation Total Reflection X-ray Fluorescence technique (SR-TXRF) was employed to identify and quantify the elements and metals of nutritional and toxicological importance in the wood samples. The analysis was performed in the Brazilian Synchrotron Light Source Laboratory, using a white beam for excitation and a Si(Li) detector for X-ray detection. In several samples, P, K, Ca, Ti, Fe, Sr, Ba and Pb were quantified. The K/Ca, K/P and Pb/Ca ratios were found to decrease towards the bark

  9. Quantification of potentially toxic elements in sewage and sludge from treatment plants in the cities of Campinas and Jaguariuna using synchrotron radiation total reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Souza, Luciana Carla Ferreira de; Canteras, Felippe Benavente; Moreira, Silvana

    2013-01-01

    The rapid urban and industrial development in last decades has brought as one of the consequences, changes in the environment. The lack of planning of city growth is, today, one of the major causes of water pollution including residential, industrial, agricultural, and hospital waste. The metals contamination is a major problem, causing serious changes to the environment, causing harm to human health. The sludge generated at sewage treatment plants, is an important source of nutrients and organic matter, and therefore it can also be reused mainly for agricultural use, since contaminants are removed. The cities of Campinas and Jaguariuna are inserted in the Campinas Metropolitan Region (CMR), one of the most dynamic regions in the Brazilian economy. Therefore, to study the anthropogenic influences of the cities, evaluated the quality of raw and treated effluent and the sludge generated in sewage treatment plants, especially with regard to heavy metals. Measurements of metals were performed by Synchrotron Radiation Total Reflection X-ray Fluorescence. For treated effluent data were compared to CONAMA 357 law and Cr, Mn, Fe, Ni, Cu, Zn, Ba and Pb showed concentrations in according with the law. To reuse in agriculture the contents were compared to the limits defined by CETESB and some elements had concentrations above to the permitted preventing its reuse. For sludge, Cr, Ni, Cu, Zn, Ba and Pb, in the two treatment plants studied, the concentrations were lower than the maximum permissible values established by CONAMA 375 law allowing the sludge application sludge on agricultural land. (author)

  10. Does a leaf absorb radiation in the near infrared (780-900 nm) region? A new approach to quantifying optical reflection, absorption and transmission of leaves.

    Science.gov (United States)

    Merzlyak, Mark N; Chivkunova, Olga B; Melø, T B; Naqvi, K Razi

    2002-01-01

    The following question is addressed here: do healthy leaves absorb, as the spectra published over the last 50 years indicate, some 5-20% of incident radiation in the 780-900 nm region? The answer is found to be negative, and previous findings result from incomplete collection of the transmitted light by the detection system (even when the leaf is placed next to, but outside, the entrance port of an integrating sphere). A simple remedy for this inherent flaw in the experimental arrangement is applied successfully to leaves (of 10 unrelated species) differing in thickness, age and pigment content. The study has shown that, from an optical standpoint, a leaf tissue is a highly scattering material, and the infinite reflectance of a leaf is exceedingly sensitive to trace amounts of absorbing components. It is shown that water contributes, in a thick leaf (Kalanchoe blossfeldiana), an easily detectable signal even in the 780-900 nm region. The practical benefits resulting from improved measurements of leaf spectra are pointed out.

  11. FIRST RESULTS FROM THE DRAGONFLY TELEPHOTO ARRAY: THE APPARENT LACK OF A STELLAR HALO IN THE MASSIVE SPIRAL GALAXY M101

    Energy Technology Data Exchange (ETDEWEB)

    Van Dokkum, Pieter G.; Merritt, Allison [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Abraham, Roberto [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H8 (Canada)

    2014-02-20

    We use a new telescope concept, the Dragonfly Telephoto Array, to study the low surface brightness outskirts of the spiral galaxy M101. The radial surface brightness profile is measured down to μ {sub g} ∼ 32 mag arcsec{sup –2}, a depth that approaches the sensitivity of star count studies in the Local Group. We convert surface brightness to surface mass density using the radial g – r color profile. The mass density profile shows no significant upturn at large radius and is well-approximated by a simple bulge + disk model out to R = 70 kpc, corresponding to 18 disk scale lengths. Fitting a bulge + disk + halo model we find that the best-fitting halo mass M{sub halo}=1.7{sub −1.7}{sup +3.4}×10{sup 8} M {sub ☉}. The total stellar mass of M101 is M{sub tot,∗}=5.3{sub −1.3}{sup +1.7}×10{sup 10} M {sub ☉}, and we infer that the halo mass fraction f{sub halo}=M{sub halo}/M{sub tot,∗}=0.003{sub −0.003}{sup +0.006}. This mass fraction is lower than that of the Milky Way (f {sub halo} ∼ 0.02) and M31 (f {sub halo} ∼ 0.04). All three galaxies fall below the f {sub halo}-M {sub tot,} {sub *} relation predicted by recent cosmological simulations that trace the light of disrupted satellites, with M101's halo mass a factor of ∼10 below the median expectation. However, the predicted scatter in this relation is large, and more galaxies are needed to better quantify this possible tension with galaxy formation models. Dragonfly is well suited for this project: as integrated-light surface brightness is independent of distance, large numbers of galaxies can be studied in a uniform way.

  12. Vertical distribution of the particle phase in tropical deep convective clouds as derived from cloud-side reflected solar radiation measurements

    Directory of Open Access Journals (Sweden)

    E. Jäkel

    2017-07-01

    Full Text Available Vertical profiles of cloud particle phase in tropical deep convective clouds (DCCs were investigated using airborne solar spectral radiation data collected by the German High Altitude and Long Range Research Aircraft (HALO during the ACRIDICON-CHUVA campaign, which was conducted over the Brazilian rainforest in September 2014. A phase discrimination retrieval based on imaging spectroradiometer measurements of DCC side spectral reflectivity was applied to clouds formed in different aerosol conditions. From the retrieval results the height of the mixed-phase layer of the DCCs was determined. The retrieved profiles were compared with in situ measurements and satellite observations. It was found that the depth and vertical position of the mixed-phase layer can vary up to 900 m for one single cloud scene. This variability is attributed to the different stages of cloud development in a scene. Clouds of mature or decaying stage are affected by falling ice particles resulting in lower levels of fully glaciated cloud layers compared to growing clouds. Comparing polluted and moderate aerosol conditions revealed a shift of the lower boundary of the mixed-phase layer from 5.6 ± 0.2 km (269 K; moderate to 6.2 ± 0.3 km (267 K; polluted, and of the upper boundary from 6.8 ± 0.2 km (263 K; moderate to 7.4 ± 0.4 km (259 K; polluted, as would be expected from theory.

  13. Evaluation of growth tree rings of Tipuana Tipu as biomonitoring of environmental pollution by synchrotron radiation total reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Moreira, Silvana; Geraldo, Simoni Michetti; Canteras, Felippe Benavente

    2013-01-01

    The bioindicators, plants or animals capable to present qualitative and/or quantitative answers, when exposed to pollutant substances. Trees record and incorporate in their log, developed year after year, the impressions of the environment, becoming possible the study of the different environmental changes, including contamination, that have occurred over the life of these trees. The selected species, Tipuana Tipu, of the Leguminosae family, is native of Argentina and Bolivia and was introduced in Brazil as an ornamental plant. It is one of the most common trees in the urban landscaping in Sao Paulo city. The present project has as main objective the determination of the content of potentially toxic elements in samples of growth the tree rings of Tipuana Tipu, previously dated, collected in strategically locations of Sao Paulo, using Synchrotron Radiation Total Reflection X-Ray Fluorescence. Samples were also collected in the Piracicaba (SP), local of little access and small flow traffic. The SR-TXRF analysis was carried out in the X-ray Fluorescence Beamline at the Brazilian Synchrotron Light Source Laboratory, located in Campinas city, Sao Paulo State, Brazil. Some trace elements present concentrations higher than considered as normal in some periods. In this paper the highest value for Pb was 123.54 μg.g -1 considered as threshold value was observed for the period 1998 to 2000 for University of Sao Paulo, Butanta site. For the same period excessive level was also observed for samples collected in Piracicaba city. In Sao Paulo city, sample collected in the campus of University of Sao Paulo (Butanta), showed the highest toxicity, with concentration above the tolerable limit for Ti, Cr and Cu. For the samples collected in Piracicaba city the concentrations of Cr, Ni, Cu, and Pb exceeding the toxicity limits. (author)

  14. Evaluation of growth tree rings of Tipuana Tipu as biomonitoring of environmental pollution by synchrotron radiation total reflection X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana; Geraldo, Simoni Michetti; Canteras, Felippe Benavente, E-mail: silvana@fec.unicamp.br, E-mail: felippe.canteras@gmail.com [Universidade Estadual de Campinas (FEC/UNICAMP), Campinas, SP (Brazil). Dept. de Saneamento e Ambiente

    2013-07-01

    The bioindicators, plants or animals capable to present qualitative and/or quantitative answers, when exposed to pollutant substances. Trees record and incorporate in their log, developed year after year, the impressions of the environment, becoming possible the study of the different environmental changes, including contamination, that have occurred over the life of these trees. The selected species, Tipuana Tipu, of the Leguminosae family, is native of Argentina and Bolivia and was introduced in Brazil as an ornamental plant. It is one of the most common trees in the urban landscaping in Sao Paulo city. The present project has as main objective the determination of the content of potentially toxic elements in samples of growth the tree rings of Tipuana Tipu, previously dated, collected in strategically locations of Sao Paulo, using Synchrotron Radiation Total Reflection X-Ray Fluorescence. Samples were also collected in the Piracicaba (SP), local of little access and small flow traffic. The SR-TXRF analysis was carried out in the X-ray Fluorescence Beamline at the Brazilian Synchrotron Light Source Laboratory, located in Campinas city, Sao Paulo State, Brazil. Some trace elements present concentrations higher than considered as normal in some periods. In this paper the highest value for Pb was 123.54 μg.g{sup -1} considered as threshold value was observed for the period 1998 to 2000 for University of Sao Paulo, Butanta site. For the same period excessive level was also observed for samples collected in Piracicaba city. In Sao Paulo city, sample collected in the campus of University of Sao Paulo (Butanta), showed the highest toxicity, with concentration above the tolerable limit for Ti, Cr and Cu. For the samples collected in Piracicaba city the concentrations of Cr, Ni, Cu, and Pb exceeding the toxicity limits. (author)

  15. Evaluation of Fe and Zn/Cu ratio in serum of patients with sickle cell anemia by total reflection X-ray fluorescence using synchrotron radiation

    International Nuclear Information System (INIS)

    Canellas, Catarine G.L.; Leitao, Roberta G.; Lopes, Ricardo T.; Bellido, Alfredo Victor B.; Anjos, Marcelino J.

    2011-01-01

    Sickle cell anemia (SCA) is a blood disorder that affects hemoglobin, the protein found in red blood cells that help carry oxygen throughout the body. In this work we have analyzed serum samples from patients with SCA by using total reflection X-ray fluorescence using synchrotron radiation (SRTXRF). The SRTXRF measurements were performed at the X-ray fluorescence beamline at Brazilian National Synchrotron Light Laboratory (LNLS), in Campinas, Sao Paulo using a polychromatic beam. We have studied forty-three patients aged 18-50 years old, suffering from SCA and Sixty healthy volunteers aged 18-60 years old. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Student's t-test was applied in order to check whether the two populations (CG x SCA) had the same mean values. It was observed that elemental concentration of P, Cl, K, Fe, Cu, Zn and Br differed significantly (α = 0.05) between groups of healthy subjects and SCA. The concentrations of K, Fe and Cu in the serum samples of patients with SCA were larger 15%, 120 % and 20 %, respectively, when compared with the CG. On the other hand, the concentrations of P (-20 %), Cl (-6 %), Zn (-25 %) and Br (-22 %) were smaller than the values determined for the control group. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples of patients with SCA group than the CG. So, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. (author)

  16. Evaluation of Fe and Zn/Cu ratio in serum of patients with sickle cell anemia by total reflection X-ray fluorescence using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Canellas, Catarine G.L.; Leitao, Roberta G.; Lopes, Ricardo T., E-mail: catarine@lin.ufrj.b, E-mail: ricardo@lin.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear. Lab. de Instrumentaco Nuclear; Carvalho, Silvia M.F., E-mail: silvia@hemorio.rj.gov.b [State Institute of Hematology Arthur de Siqueira Cavalcanti (HEMORIO), Rio de Janeiro, RJ (Brazil); Bellido, Alfredo Victor B., E-mail: alfredo@ien.gov.b [Federal Fluminense University (UFF), Niteroi, RJ (Brazil). Chemistry Inst.; Anjos, Marcelino J., E-mail: marcelin@lin.ufrj.b [State University of Rio de Janeiro (UERJ), RJ (Brazil). Physics Inst.

    2011-07-01

    Sickle cell anemia (SCA) is a blood disorder that affects hemoglobin, the protein found in red blood cells that help carry oxygen throughout the body. In this work we have analyzed serum samples from patients with SCA by using total reflection X-ray fluorescence using synchrotron radiation (SRTXRF). The SRTXRF measurements were performed at the X-ray fluorescence beamline at Brazilian National Synchrotron Light Laboratory (LNLS), in Campinas, Sao Paulo using a polychromatic beam. We have studied forty-three patients aged 18-50 years old, suffering from SCA and Sixty healthy volunteers aged 18-60 years old. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Student's t-test was applied in order to check whether the two populations (CG x SCA) had the same mean values. It was observed that elemental concentration of P, Cl, K, Fe, Cu, Zn and Br differed significantly ({alpha} = 0.05) between groups of healthy subjects and SCA. The concentrations of K, Fe and Cu in the serum samples of patients with SCA were larger 15%, 120 % and 20 %, respectively, when compared with the CG. On the other hand, the concentrations of P (-20 %), Cl (-6 %), Zn (-25 %) and Br (-22 %) were smaller than the values determined for the control group. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples of patients with SCA group than the CG. So, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. (author)

  17. Evaluation of Fe and Zn/Cu ratio in serum of patients with sickle cell anemia by total reflection X-ray fluorescence using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Canellas, Catarine G.L.; Leitao, Roberta G; Lopes, Ricardo T., E-mail: catarine@lin.ufrj.b, E-mail: ricardo@lin.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear. Lab. de Instrumentaco Nuclear; Carvalho, Silvia M.F., E-mail: silvia@hemorio.rj.gov.b [State Institute of Hematology Arthur de Siqueira Cavalcanti (HEMORIO), Rio de Janeiro, RJ (Brazil); Bellido, Alfredo Victor B., E-mail: alfredo@ien.gov.b [Federal Fluminense University (UFF), Niteroi, RJ (Brazil). Chemistry Inst.; Anjos, Marcelino J., E-mail: marcelin@lin.ufrj.b [State University of Rio de Janeiro (UERJ), RJ (Brazil). Physics Inst.

    2011-07-01

    Sickle cell anemia (SCA) is a blood disorder that affects hemoglobin, the protein found in red blood cells that help carry oxygen throughout the body. In this work we have analyzed serum samples from patients with SCA by using total reflection X-ray fluorescence using synchrotron radiation (SRTXRF). The SRTXRF measurements were performed at the X-ray fluorescence beamline at Brazilian National Synchrotron Light Laboratory (LNLS), in Campinas, Sao Paulo using a polychromatic beam. We have studied forty-three patients aged 18-50 years old, suffering from SCA and Sixty healthy volunteers aged 18-60 years old. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Student's t-test was applied in order to check whether the two populations (CG x SCA) had the same mean values. It was observed that elemental concentration of P, Cl, K, Fe, Cu, Zn and Br differed significantly ({alpha} = 0.05) between groups of healthy subjects and SCA. The concentrations of K, Fe and Cu in the serum samples of patients with SCA were larger 15%, 120 % and 20 %, respectively, when compared with the CG. On the other hand, the concentrations of P (-20 %), Cl (-6 %), Zn (-25 %) and Br (-22 %) were smaller than the values determined for the control group. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples of patients with SCA group than the CG. So, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. (author)

  18. The Reflective Learning Continuum: Reflecting on Reflection

    Science.gov (United States)

    Peltier, James W.; Hay, Amanda; Drago, William

    2005-01-01

    The importance of reflection to marketing educators is increasingly recognized. However, there is a lack of empirical research that considers reflection within the context of both the marketing and general business education literature. This article describes the use of an instrument that can be used to measure four identified levels of a…

  19. Hovering and targeting flight simulations of a dragonfly-like flapping wing-body model by the immersed boundary-lattice Boltzmann method

    International Nuclear Information System (INIS)

    Hirohashi, Kensuke; Inamuro, Takaji

    2017-01-01

    Hovering and targeting flights of the dragonfly-like flapping wing-body model are numerically investigated by using the immersed boundary-lattice Boltzmann method. The governing parameters of the problem are the Reynolds number Re , the Froude number Fr , and the non-dimensional mass m . We set the parameters at Re = 200, Fr = 15 and m  = 51. First, we simulate free flights of the model for various values of the phase difference angle ϕ between the forewing and the hindwing motions and for various values of the stroke angle β between the stroke plane and the horizontal plane. We find that the vertical motion of the model depends on the phase difference angle ϕ , and the horizontal motion of the model depends on the stroke angle β . Secondly, using the above results we try to simulate the hovering flight by dynamically changing the phase difference angle ϕ and the stroke angle β . The hovering flight can be successfully simulated by a simple proportional controller of the phase difference angle and the stroke angle. Finally, we simulate a targeting flight by dynamically changing the stroke angle β . (paper)

  20. Dragonfly Mercury Project—A citizen science driven approach to linking surface-water chemistry and landscape characteristics to biosentinels on a national scale

    Science.gov (United States)

    Eagles-Smith, Collin A.; Nelson, Sarah J.; Willacker,, James J.; Flanagan Pritz, Colleen M.; Krabbenhoft, David P.

    2016-02-29

    Mercury is a globally distributed pollutant that threatens human and ecosystem health. Even protected areas, such as national parks, are subjected to mercury contamination because it is delivered through atmospheric deposition, often after long-range transport. In aquatic ecosystems, certain environmental conditions can promote microbial processes that convert inorganic mercury to an organic form (methylmercury). Methylmercury biomagnifies through food webs and is a potent neurotoxicant and endocrine disruptor. The U.S. Geological Survey (USGS), the University of Maine, and the National Park Service (NPS) Air Resources Division are working in partnership at more than 50 national parks across the United States, and with citizen scientists as key participants in data collection, to develop dragonfly nymphs as biosentinels for mercury in aquatic food webs. To validate the use of these biosentinels, and gain a better understanding of the connection between biotic and abiotic pools of mercury, this project also includes collection of landscape data and surface-water chemistry including mercury, methylmercury, pH, sulfate, and dissolved organic carbon and sediment mercury concentration. Because of the wide geographic scope of the research, the project also provides a nationwide “snapshot” of mercury in primarily undeveloped watersheds.

  1. Hovering and targeting flight simulations of a dragonfly-like flapping wing-body model by the immersed boundary-lattice Boltzmann method

    Energy Technology Data Exchange (ETDEWEB)

    Hirohashi, Kensuke; Inamuro, Takaji, E-mail: inamuro@kuaero.kyoto-u.ac.jp [Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan)

    2017-08-15

    Hovering and targeting flights of the dragonfly-like flapping wing-body model are numerically investigated by using the immersed boundary-lattice Boltzmann method. The governing parameters of the problem are the Reynolds number Re , the Froude number Fr , and the non-dimensional mass m . We set the parameters at Re = 200, Fr = 15 and m  = 51. First, we simulate free flights of the model for various values of the phase difference angle ϕ between the forewing and the hindwing motions and for various values of the stroke angle β between the stroke plane and the horizontal plane. We find that the vertical motion of the model depends on the phase difference angle ϕ , and the horizontal motion of the model depends on the stroke angle β . Secondly, using the above results we try to simulate the hovering flight by dynamically changing the phase difference angle ϕ and the stroke angle β . The hovering flight can be successfully simulated by a simple proportional controller of the phase difference angle and the stroke angle. Finally, we simulate a targeting flight by dynamically changing the stroke angle β . (paper)

  2. Reflective perspectives

    International Nuclear Information System (INIS)

    Yoder, R.E.

    1985-01-01

    There is a need to provide to the radiation industry quality, reliable radiation detecting instruments. There is a need to provide an overall assessment of instrument performance under standard conditions but one must not overlook the importance of a qualified health physicist to assure the proper instrument selection for a measurement and the correct interpretation of the readings or data accumulated. Innovation in problem areas must be fostered to achieve advances in dosimetry, radiation measurements, and radiation control

  3. Demystifying the reflective clinical journal

    International Nuclear Information System (INIS)

    Milinkovic, Danielle; Field, Nikki

    2005-01-01

    Student learning on clinical placement is a complex issue and cannot be defined solely by just doing things. Reflection during clinical practice is essential if the student is going to learn from the experience. Therefore it is important for educators to include as part of clinical education programs learning strategies that encourage reflection. The reflective clinical journal is an educational tool that is employed by the School of Medical Radiation Sciences at the University of Sydney to encourage reflection of undergraduate radiation therapy students whilst on clinical placement. This discussion paper explores the key concepts of reflection and the reflective clinical journal. Due to the paucity of information about this issue in radiation therapy the literature reviewed is from across all areas of the health sciences

  4. Reflective photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Lentine, Anthony L.; Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Goeke, Ronald S.

    2018-03-06

    A photovoltaic module includes colorized reflective photovoltaic cells that act as pixels. The colorized reflective photovoltaic cells are arranged so that reflections from the photovoltaic cells or pixels visually combine into an image on the photovoltaic module. The colorized photovoltaic cell or pixel is composed of a set of 100 to 256 base color sub-pixel reflective segments or sub-pixels. The color of each pixel is determined by the combination of base color sub-pixels forming the pixel. As a result, each pixel can have a wide variety of colors using a set of base colors, which are created, from sub-pixel reflective segments having standard film thicknesses.

  5. Analyses of heavy metals in sewage and sludge from treatment plants in the cities of Campinas and Jaguariúna, using synchrotron radiation total reflection X-rayfluorescence

    International Nuclear Information System (INIS)

    Souza, L.C.F.; Canteras, F.B.; Moreira, S.

    2014-01-01

    A major consequence of accelerated urban and industrial development in the last decades is water pollution. In particular, metal contamination is a significant problem, causing serious changes to the environment and adversely affecting human health. The cities of Campinas and Jaguariúna are inserted in the Campinas Metropolitan Region (CMR), one of the most dynamic regions in the Brazilian economy, accounting for 2.7% of Gross National Product (GNP) and 7.83% of São Paulo State Product—or approximately $ 70.7 billion per year. Besides having a strong economy, the region also presents an infrastructure that provides the development of the entire metropolitan area. Therefore, to study the anthropogenic influences of the cities, the evaluation of the quality of raw and treated effluent and, the sludge generated in sewage treatment plants (STP), especially with regard to heavy metals was performed by Total Reflection X-Ray Fluorescence with Synchrotron Radiation technique. The results were compared with the allowed values established by Brazilian Legislation. For raw and treated effluents collected in Jaguariúna and Campinas city in the Stations of Treatment of Sewage (Camanducaia and Anhumas), Cr presented higher concentrations than the maximum allowed values established by CONAMA 357. However, it is necessary to do other studies to define the fraction of Cr +3 and Cr +6 to compare to the new legislation. The other elements were in agreement with established regulations. For sludge sampled in the same locations, the concentrations of Cr, Cu, Pb, Ni and Zn were compared with the CONAMA 375 and showed values smaller than the maximum allowed values, indicating the possibility to re-use the sludge. - Highlights: ► Analysis of sewage and sludge composition using SR-TXRF. ► Determination of the potentially toxic elements like Cr, Ni, Cu, Zn and Pb. ► Concentrations determined were compared with Brazilian quality standards. ► It was discovered possible illegal

  6. Is superficial burn caused by ultraviolet radiation (sunburn) comparable to superficial burn caused by heat--a histomorphological comparison by in vivo Reflectance-Mode-Confocal Microscopy.

    Science.gov (United States)

    Altintas, M A; Altintas, A A; Guggenheim, M; Busch, K H; Niederbichler, A D; Aust, M C; Vogt, P M

    2009-12-01

    Regardless of the underlying cause, both sunburn and superficial thermal injuries are classified as first-degree burns, since data on morphological differences are scarce. Reflectance-Mode-Confocal Microscopy (RMCM) enables high-resolution non-invasive investigation of the human skin. We studied in vivo histomorphological alterations in both sunburn and superficial thermal injuries using RMCM. Ten patients (6 female, 4 male; aged 28.4 +/- 10.6 years) with first-degree thermal-contact Injuries (TI group), and 9 sunburned patients (SB group; 7 female, 2 male; aged 30.2 +/- 16.4 years), to a maximum extent of 10% of the body surface were evaluated 24 h after burn injury using RMCM. The following parameters were obtained using RMCM: stratum corneum thickness, epidermal thickness, basal layer thickness, granular cell size. Compared to the controls (12.8 +/- 2.5 microm), stratum corneum thickness decreased significantly to 10.6 +/- 2.1 microm in the TI group, whereas it increased significantly to 16.4 +/- 3.1 microm in the SB group. The epidermal thickness did not differ significantly in the TI group (47.9 +/- 2.3 microm) and SB group (49.1 +/- 3.5 microm); however, both increased significantly compared to their respective controls (41.8 +/- 1.4 microm). The basal layer thickness increased more in the SB group compared to the TI group (17.9 +/- 1.4 microm vs. 15.6 +/- 1.1 microm). Both differed also significantly compared to their controls (13.8 +/- 0.9 microm). The granular cell size increased significantly in both groups compared to the controls (731 +/- 42 microm); however, a significantly higher increase was observed in the TI group (852 +/- 58 microm) compared to the SB group (784 +/- 61 microm). Ultraviolet radiation seems to influence predominantly deeper epidermal layers, whereas heat-induced burns affect more superficial epidermal layers. The term 'First-degree burn' should not be used synonymously for sunburn and superficial thermal burn injuries. Conflicts of

  7. Final report for the project "Improving the understanding of surface-atmosphere radiative interactions by mapping surface reflectance over the ARM CART site" (award DE-FG02-02ER63351)

    Energy Technology Data Exchange (ETDEWEB)

    Alexander P. Trishchenko; Yi Luo; Konstantin V. Khlopenkov, William M. Park; Zhanqing Li; Maureen Cribb

    2008-11-28

    Surface spectral reflectance (albedo) is a fundamental variable affecting the transfer of solar radiation and the Earth’s climate. It determines the proportion of solar energy absorbed by the surface and reflected back to the atmosphere. The International Panel on Climate Change (IPCC) identified surface albedo among key factors influencing climate radiative forcing. Accurate knowledge of surface reflective properties is important for advancing weather forecasting and climate change impact studies. It is also important for determining radiative impact and acceptable levels of greenhouse gases in the atmosphere, which makes this work strongly linked to major scientific objectives of the Climate Change Research Division (CCRD) and Atmospheric Radiation Measurement (ARM) Program. Most significant accomplishments of eth project are listed below. I) Surface albedo/BRDF datasets from 1995 to the end of 2004 have been produced. They were made available to the ARM community and other interested users through the CCRS public ftp site ftp://ftp.ccrs.nrcan.gc.ca/ad/CCRS_ARM/ and ARM IOP data archive under “PI data Trishchenko”. II) Surface albedo properties over the ARM SGP area have been described for 10-year period. Comparison with ECMWF data product showed some deficiencies in the ECMWF surface scheme, such as missing some seasonal variability and no dependence on sky-conditions which biases surface energy budget and has some influence of the diurnal cycle of upward radiation and atmospheric absorption. III) Four surface albedo Intensive Observation Period (IOP) Field Campaigns have been conducted for every season (August, 2002, May 2003, February 2004 and October 2004). Data have been prepared, documented and transferred to ARM IOP archive. Nine peer-reviewed journal papers and 26 conference papers have been published.

  8. Reflected Glory

    Science.gov (United States)

    2011-02-01

    The nebula Messier 78 takes centre stage in this image taken with the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile, while the stars powering the bright display take a backseat. The brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light. Igor Chekalin was the overall winner of ESO's Hidden Treasures 2010 astrophotography competition with his image of this stunning object. Messier 78 is a fine example of a reflection nebula. The ultraviolet radiation from the stars that illuminate it is not intense enough to ionise the gas to make it glow - its dust particles simply reflect the starlight that falls on them. Despite this, Messier 78 can easily be observed with a small telescope, being one of the brightest reflection nebulae in the sky. It lies about 1350 light-years away in the constellation of Orion (The Hunter) and can be found northeast of the easternmost star of Orion's belt. This new image of Messier 78 from the MPG/ESO 2.2-metre telescope at the La Silla Observatory is based on data selected by Igor Chekalin in his winning entry to the Hidden Treasures competition [1]. The pale blue tint seen in the nebula in this picture is an accurate representation of its dominant colour. Blue hues are commonly seen in reflection nebulae because of the way the starlight is scattered by the tiny dust particles that they contain: the shorter wavelength of blue light is scattered more efficiently than the longer wavelength red light. This image contains many other striking features apart from the glowing nebula. A thick band of obscuring dust stretches across the image from the upper left to the lower right, blocking the light from background stars. In the bottom right corner, many curious pink structures are also visible, which are created by jets of material being ejected from stars that have recently formed and are still buried deep in dust clouds. Two bright stars, HD 38563A and

  9. Effect of near-infrared-radiation reflective screen materials on ventilation requirement, crop transpiration and water use efficiency of a greenhouse rose crop

    NARCIS (Netherlands)

    Stanghellini, C.; Jianfeng, D.; Kempkes, F.L.K.

    2011-01-01

    The effect of Near Infrared (NIR)-reflective screen material on ventilation requirement, crop transpiration and water use efficiency of a greenhouse rose crop was investigated in an experiment whereby identical climate was ensured in greenhouse compartments installed with either NIR-reflective or

  10. Coupled soil-leaf-canopy and atmosphere radiative transfer modeling to simulate hyperspectral multi-angular surface reflectance and TOA radiance data

    NARCIS (Netherlands)

    Verhoef, W.; Bach, H.

    2007-01-01

    Coupling radiative transfer models for the soil background and vegetation canopy layers is facilitated by means of the four-stream flux interaction concept and use of the adding method. Also the coupling to a state-of-the-art atmospheric radiative transfer model like MODTRAN4 can be established in

  11. Personal Reflections

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Personal Reflections. Articles in Resonance – Journal of Science Education. Volume 6 Issue 3 March 2001 pp 90-93 Personal Reflections. Why did I opt for Career in Science? Jayant V Narlikar · More Details Fulltext PDF. Volume 9 Issue 8 August 2004 pp 89-89 ...

  12. Reflection ciphers

    DEFF Research Database (Denmark)

    Boura, Christina; Canteaut, Anne; Knudsen, Lars Ramkilde

    2017-01-01

    study the necessary properties for this coupling permutation. Special care has to be taken of some related-key distinguishers since, in the context of reflection ciphers, they may provide attacks in the single-key setting.We then derive some criteria for constructing secure reflection ciphers...

  13. Quantifying Reflection

    DEFF Research Database (Denmark)

    Alcock, Gordon Lindsay

    2013-01-01

    ´ These are all based on Blooms taxonomy and levels of competence and form a major part of individual student and group learning portfolios. Key Words :Project-Based learning, Reflective Portfolios, Self assessment, Defining learning gains, Developing learning strategies , Reflections on and for learning....... It contrasts the students’ self-assessment in a range of ‘product’ skills such as Revit, Structural Design, Mathematics of construction, Technical Installations; as well as ‘process’ competencies such as ‘Working in a team’, Sharing knowledge, Maintaining a portfolio and Reflecting ON learning and FOR learning......This paper documents 1st semester student reflections on “learning to learn” in a team-based PBL environment with quantitative and qualitative student reflective feedback on the learning gains of 60 Architectural Technology and Construction Management students at VIA University College, Denmark...

  14. Free flight simulations of a dragonfly-like flapping wing-body model using the immersed boundary-lattice Boltzmann method

    International Nuclear Information System (INIS)

    Minami, Keisuke; Suzuki, Kosuke; Inamuro, Takaji

    2015-01-01

    Free flights of the dragonfly-like flapping wing-body model are numerically investigated using the immersed boundary-lattice Boltzmann method. The governing parameters of the problem are the Reynolds number Re, the Froude number Fr, and the non-dimensional mass m, and we set the parameters at Re = 200, Fr = 15, and m = 51. First, we simulate free flights of the model without the pitching rotation for various values of the phase lag angle ϕ between the forewing and the hindwing motions. We find that the wing-body model goes forward in spite of ϕ, and the model with ϕ = 0 ∘ and 90 ∘ goes upward against gravity. The model with ϕ =180 ∘ goes almost horizontally, and the model with ϕ =270 ∘ goes downward. That is, the moving direction of the model depends on the phase lag angle ϕ. Secondly, we simulate free flights with the pitching rotation for various values of the phase lag angle ϕ. It is found that in spite of ϕ the wing-body model turns gradually in the nose-up direction and goes back and down as the pitching angle Θ c increases. That is, the wing-body model cannot make a stable forward flight without control. Finally, we show a way to control the pitching motion by changing the lead–lag angle γ(t). We propose a simple proportional controller of γ(t) which makes stable flights within Θ c =±5 ∘ and works well even for a large disturbance. (paper)

  15. Rapid biosynthesis of silver nanoparticles using Crotalaria verrucosa leaves against the dengue vector Aedes aegypti: what happens around? An analysis of dragonfly predatory behaviour after exposure at ultra-low doses.

    Science.gov (United States)

    Murugan, Kadarkarai; Sanoopa, C P; Madhiyazhagan, Pari; Dinesh, Devakumar; Subramaniam, Jayapal; Panneerselvam, Chellasamy; Roni, Mathath; Suresh, Udaiyan; Nicoletti, Marcello; Alarfaj, Abdullah A; Munusamy, Murugan A; Higuchi, Akon; Kumar, Suresh; Perumalsamy, Haribalan; Ahn, Young-Joon; Benelli, Giovanni

    2016-01-01

    Aedes aegypti is a primary vector of dengue, a mosquito-borne viral disease infecting 50-100 million people every year. Here, we biosynthesised mosquitocidal silver nanoparticles (AgNP) using the aqueous leaf extract of Crotalaria verrucosa. The green synthesis of AgNP was studied by UV-vis spectroscopy, SEM, EDX and FTIR. C. verrucosa-synthesised AgNPs were toxic against A. aegypti larvae and pupae. LC50 of AgNP ranged from 3.496 ppm (I instar larvae) to 17.700 ppm (pupae). Furthermore, we evaluated the predatory efficiency of dragonfly nymphs, Brachydiplax sobrina, against II and III instar larvae of A. aegypti in an aquatic environment contaminated with ultra-low doses of AgNP. Under standard laboratory conditions, predation after 24 h was 87.5% (II) and 54.7% (III). In an AgNP-contaminated environment, predation was 91 and 75.5%, respectively. Overall, C. verrucosa-synthesised AgNP could be employed at ultra-low doses to reduce larval population of dengue vectors enhancing predation rates of dragonfly nymphs.

  16. Radiation imaging

    Energy Technology Data Exchange (ETDEWEB)

    Redmayne, I.

    1986-05-21

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed.

  17. Radiation imaging

    International Nuclear Information System (INIS)

    Redmayne, Ian.

    1986-01-01

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed. (author)

  18. Superradiance or total reflection?

    CERN Document Server

    László, András

    2014-01-01

    Numerical evolution of massless scalar fields on Kerr background is studied. The initial data specifications are chosen to have compact support separated from the ergoregion and to yield nearly monochromatic incident wave packets. The initial data is also tuned to maximize the effect of superradiance. Evidences are shown indicating that instead of the anticipated energy extraction from black hole the incident radiation fail to reach the ergoregion rather it suffers a nearly perfect reflection.

  19. Application of a method based on the measurement of radiation reflectance when estimating the sensitivity of selected grain maize hybrids to the herbicide CALLISTO 480 SC + ATPLUS 463

    Directory of Open Access Journals (Sweden)

    Michal Vondra

    2009-01-01

    Full Text Available The application of methods based on measurements of photosynthesis efficiency is now more and more popular and used not only for the evaluation of the efficiency of herbicides but also for the estimation of their phytotoxicity to the cultivated crop. These methods enable to determine also dif­fe­ren­ces in the sensitivity of cultivars and/or hybrids to individual herbicides. The advantage of these methods consists above all in the speed and accuracy of measuring.In a field experiment, the sensitivity of several selected grain maize hybrids (EDENSTAR, NK AROBASE, NK LUGAN, LG 33.30 and NK THERMO to the herbicide CALLISTO 480 SC + ATPLUS 463 was tested for a period of three years. The sensitivity to a registered dose of 0.25 l . ha−1 + 0.5 % was measured by means of the apparatus PS1 meter, which could measure the reflected radiation. Measurements of sensitivity of hybrids were performed on the 2nd, 3rd, 4th, 5th and 8th day after the application of the tested herbicide, i.e. in the growing stage of the 3rd–5th leaf. Plant material was harvested using a small-plot combine harvester SAMPO 2010. Samples were weighed and converted to the yield with 15 % of moisture in grain DM.The obtained three-year results did not demonstrate differences in sensitivity of tested hybrids to the registered dose of the herbicide CALLISTO 480 SC + ATPLUS 463 (i.e. 0.25 l . ha−1 + 0,5 %. Recorded results indicated that for the majority of tested hybrids the most critical were the 4th and the 5th day after the application; on these days the average PS1 values were the highest at all. In years 2005 and 2007, none of the tested hybrids exceeded the limit value 15 (which indicated a certain decrease in the efficiency of photosynthesis. Although in 2006 three of tested hybrids showed a certain decrease in photosynthetic activity (i.e. EDENSTAR and NK AROBASE on the 3rd day and NK LUGAN on the 2nd–4th day after the application, no visual symptoms

  20. Selectively reflective transparent sheets

    Science.gov (United States)

    Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

    2015-08-01

    We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

  1. Reflective optics

    CERN Document Server

    Korsch, Dietrich

    1991-01-01

    This is the first book dedicated exclusively to all-reflective imaging systems. It is a teaching tool as well as a practical design tool for anyone who specializes in optics, particularly for those interested in telescopes, infrared, and grazing-incidence systems. The first part of the book describes a unified geometric optical theory of all-reflective imaging systems (from near-normal to grazing incidence) developed from basic principles. The second part discusses correction methods and a multitude of closed-form solutions of well-corrected systems, supplemented with many conventional and unc

  2. An Improved Measurement Method for the Strength of Radiation of Reflective Beam in an Industrial Optical Sensor Based on Laser Displacement Meter

    OpenAIRE

    Youngchul Bae

    2016-01-01

    An optical sensor such as a laser range finder (LRF) or laser displacement meter (LDM) uses reflected and returned laser beam from a target. The optical sensor has been mainly used to measure the distance between a launch position and the target. However, optical sensor based LRF and LDM have numerous and various errors such as statistical errors, drift errors, cyclic errors, alignment errors and slope errors. Among these errors, an alignment error that contains measurement error for the stre...

  3. Development of remediation/decontamination strategies reflecting local conditions by the EU long-term radiation exposure model for inhabited areas (ERMIN)

    International Nuclear Information System (INIS)

    Sakuma, Kazuyuki; Nanba, Kenji; Terada, Akihiko; Hosomi, Masaaki

    2015-01-01

    The European model for inhabited areas (ERMIN), developed for prediction of radioactive compounds Chernobyl accident, was applied at Tomioka in Fukushima Prefecture as a model region for decontamination to investigate its feasibility. The application of ERMIN to eight compartments with each 100 x 100 m in this region, where decontamination was actually performed, confirmed that observed air dose rates were within the calculated counterparts irrespective of presence or absence of a term on environment half life for two months. With simulation sets capable of reproducing an air dose rate during a decontamination term, decontamination strategies incorporating five evaluation items, i.e. reduction of radiation exposure to inhabitants, cost for decontamination, the amount of waste, work effort, and the amount of radiation exposure for a worker, were proposed and compared. By initiating decontamination 9 months after the accident in Fukushima, radiation exposure to inhabitants, who continue to live at the modeled region, is reduced by about 24 mSv for the ensuring 15 months. Furthermore, decontamination strategies were compared by prioritizing the five evaluation items. (author)

  4. Late effects of 60Co γ radiation on the bovine oocyte as reflected by oocyte survival, follicular development, and reproductive performance

    International Nuclear Information System (INIS)

    Erickson, B.H.; Reynolds, R.A.; Murphree, R.L.

    1976-01-01

    Long-term effects of ionizing radiation on the oocyte of a long-lived mammal have not been determined. Therefore, 280 15- to 18-month-old grade Herefords were partitioned among five groups and irradiated with either 0, 200, 300, 400, or 300 + 300 (55 days between fractions) R of 60 Co γ radiation at exposure rates of 0.69 or 0.78 R/min. Dose to the ovaries was 37 +- 3 percent of the dose measured in air. Germ cell effects were assessed in the survivors through (1) counts of germ cells and follicles in serially sectioned ovaries, (2) incidence of ovarian abnormalities, and (3) reproductive performance. Neither germ cell nor follicular counts were significantly affected by irradiation (P greater than 0.05). Incidence of ovarian abnormalities was not altered nor was reproductive performance or quality of offspring. It was concluded, therefore, that a near lethal postpuberally applied dose of γ radiation would not affect the reproductive capacity of the bovine female

  5. Low cloud investigations for project FIRE: Island studies of cloud properties, surface radiation, and boundary layer dynamics. A simulation of the reflectivity over a stratocumulus cloud deck by the Monte Carlo method. M.S. Thesis Final Report

    Science.gov (United States)

    Ackerman, Thomas P.; Lin, Ruei-Fong

    1993-01-01

    The radiation field over a broken stratocumulus cloud deck is simulated by the Monte Carlo method. We conducted four experiments to investigate the main factor for the observed shortwave reflectively over the FIRE flight 2 leg 5, in which reflectivity decreases almost linearly from the cloud center to cloud edge while the cloud top height and the brightness temperature remain almost constant through out the clouds. From our results, the geometry effect, however, did not contribute significantly to what has been observed. We found that the variation of the volume extinction coefficient as a function of its relative position in the cloud affects the reflectivity efficiently. Additional check of the brightness temperature of each experiment also confirms this conclusion. The cloud microphysical data showed some interesting features. We found that the cloud droplet spectrum is nearly log-normal distributed when the clouds were solid. However, whether the shift of cloud droplet spectrum toward the larger end is not certain. The decrease of number density from cloud center to cloud edges seems to have more significant effects on the optical properties.

  6. Reflective Efficacy

    Directory of Open Access Journals (Sweden)

    Carla Bagnoli

    2018-04-01

    Full Text Available The purpose of this paper is to highlight some difficulties of Neil Sinhababu’s Humean theory of agency, which depend on his radically reductivist approach, rather than to his Humean sympathies. The argument is that Sinhababu’s theory builds upon a critique of reflective agency which is based on equivocation and misunderstandings of the Kantian approach. Ultimately, the objection is that his reductivist view is unequipped to address the rclassical problems of rational deliberation and agential authority.

  7. Monitoring environmental pollution of trace elements in tree-rings by synchrotron radiation total reflection X-ray fluorescence analysis (SR-TXRF)

    International Nuclear Information System (INIS)

    Moreira, Silvana; Vives, Ana Elisa S. de; Brienza, Sandra Maria B.; Medeiros, Jean Gabriel S.; Tomazello Filho, Mario; Zucchi, Orgheda L.A.D.; Nascimento Filho, Virgilio F.

    2005-01-01

    This paper aims to study the environmental pollution in the tree development, as a manner to evaluate its use as bioindicator in urban and country sides. The sample collecting was carry out in Piracicaba city, Sao Paulo State, that presents high level of environmental contamination of the water, soil and air, due industrial activities, vehicles combustion, sugar-cane leaves burning in the harvesting, etc. It was selected the Caesalpinia peltophoroides ('Sibipiruna') specie because its very used in urban arborization. It was employed the analytical technique named total reflection X-ray fluorescence (TXRF) to identify and quantify the elements and metals of nutritional and toxicological importance in the wood samples. The analysis was done in the Brazilian Synchrotron Light Laboratory, using a white beam for excitation and a Si(Li) detector for characteristic X-ray detection. It was quantified the P, K, Ca, Ti, Fe, Sr, Ba e Pb elements. (author)

  8. Monitoring environmental pollution of trace elements in tree-rings by synchrotron radiation total reflection X-ray fluorescence analysis (SR-TXRF)

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo]. E-mail: Silvana@fec.unicamp.br; Vives, Ana Elisa S. de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Brienza, Sandra Maria B. [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil) Faculdade de Ciencias Matematicas, da Natureza e de Tecnologia da Informacao]. E-mail: sbrienza@unimep.br; Medeiros, Jean Gabriel S.; Tomazello Filho, Mario [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz]. E-mail: jeangm@esalq.usp.br; mtomazel@esalq.usp.br; Zucchi, Orgheda L.A.D. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Nascimento Filho, Virgilio F. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Instrumentacao Nuclear]. E-mail: virgilio@cena.usp.br

    2005-07-01

    This paper aims to study the environmental pollution in the tree development, as a manner to evaluate its use as bioindicator in urban and country sides. The sample collecting was carry out in Piracicaba city, Sao Paulo State, that presents high level of environmental contamination of the water, soil and air, due industrial activities, vehicles combustion, sugar-cane leaves burning in the harvesting, etc. It was selected the Caesalpinia peltophoroides ('Sibipiruna') specie because its very used in urban arborization. It was employed the analytical technique named total reflection X-ray fluorescence (TXRF) to identify and quantify the elements and metals of nutritional and toxicological importance in the wood samples. The analysis was done in the Brazilian Synchrotron Light Laboratory, using a white beam for excitation and a Si(Li) detector for characteristic X-ray detection. It was quantified the P, K, Ca, Ti, Fe, Sr, Ba e Pb elements. (author)

  9. On Reflection

    DEFF Research Database (Denmark)

    Blasco, Maribel

    2012-01-01

    produces: that the self is accessible and transcendable, that reflexivity is universal across space and time, and that the self can act as its own remedial change agent or ‘inner consultant.’ I argue that because reflexivity is understood in many different ways, attention to definition is crucial, both...... on the concepts of selfhood that prevail and how notions of difference are constructed. First, I discuss how the dominant usages of reflexivity in intercultural education reflect and reproduce a Cartesian view of the self that shapes how ICC is conceptualized and taught. I discuss three assumptions that this view...

  10. Inspiring Reflections

    DEFF Research Database (Denmark)

    Muchie, Mammo

    2011-01-01

    A numberof Chris Freeman's colleagues were asked to reflect on what they thought describes his life and work in a few words. Some of the colleagues replied including former SPRU students that were taught or supervised by Chris Freeman. Their views on what they thought were Chris Freeman's defining...... life is not free from fluctuations, cycles, disruptions, crises and destructions both human and ecological. Innovation research ought to position itself to address environmental, financial and economic crises. The third is innovation research for development by addressing not only poverty erdaication...

  11. Reflective Writing

    DEFF Research Database (Denmark)

    Ahrenkiel Jørgensen, Andriette

    2016-01-01

    In Breve fra min Have (Letters from my Garden), the Swedish landscape architect, Sven-Ingvar Andersson, produces dialogues about his garden to a wide circle of friends, colleagues, deceased and still living acquaintances such as Karen Blixen, Gertrude Stein, C. Th. Sørensen, Albrecht Dürer, Peter...... Høeg etetera. The dialogues work as a tool of reflection in terms of providing opportunity to examine his own beliefs, to explore the possible reasons for engaging in a particular activity. On the basis of Sven-Ingvar Andersson’s book a teaching program at the Aarhus School of Architecture provides...

  12. Neutron reflectivity

    Directory of Open Access Journals (Sweden)

    Cousin Fabrice

    2015-01-01

    Full Text Available The specular neutron reflectivity is a technique enabling the measurement of neutron scattering length density profile perpendicular to the plane of a surface or an interface, and thereby the profile of chemical composition. The characteristic sizes that are probed range from around 5 Å up 5000 Å. It is a scattering technique that averages information on the entire surface and it is therefore not possible to obtain information within the plane of the interface. The specific properties of neutrons (possibility of tuning the contrast by isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons makes it particularly interesting in the fields of soft matter, biophysics and magnetic thin films. This course is a basic introduction to the technique and does not address the magnetic reflectivity. It is composed of three parts describing respectively its principle and its formalism, the experimental aspects of the method (spectrometers, samples and two examples related to the materials for energy.

  13. Measurement of the ferric diffusion coefficient in agarose and gelatine gels by utilization of the evolution of a radiation induced edge as reflected in relaxation rate images

    International Nuclear Information System (INIS)

    Pedersen, Torje V.; Olsen, Dag R.; Skretting, Arne

    1997-01-01

    A method has been developed to determine the diffusion coefficients of ferric ions in ferrous sulphate doped gels. A radiation induced edge was created in the gel, and two spin-echo sequences were used to acquire a pair of images of the gel at different points of time. For each of these image pairs, a longitudinal relaxation rate image was derived. From profiles through these images, the standard deviations of the Gaussian functions that characterize diffusion were determined. These data provided the basis for the determination of the ferric diffusion coefficients by two different methods. Simulations indicate that the use of single spin-echo images in this procedure may in some cases lead to a significant underestimation of the diffusion coefficient. The technique was applied to different agarose and gelatine gels that were prepared, irradiated and imaged simultaneously. The results indicate that the diffusion coefficient is lower in a gelatine gel than in an agarose gel. Addition of xylenol orange to a gelatine gel lowers the diffusion coefficient from 1.45 to 0.81 mm 2 h -1 , at the cost of significantly lower R 1 sensitivity. The addition of benzoic acid to the latter gel did not increase the R 1 sensitivity. (author) OK

  14. ICRP 2015. International symposium on the radiation protection system. Report and reflection on a significant symposium; ICRP 2015. 3. Internationales Symposium zum System des Strahlenschutzes. Bericht und Reflexion ueber ein bedeutsames Symposium

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Bernd

    2016-08-01

    The ICRP international symposium on the radiation protection system provides always extensive information on new developments in radiation protection. The ICRP 2105 discussed the following issues: radiation effects of low dose irradiation, dose coefficients for internal and external exposures, radiation protection in nuclear medicine, application of ICRP recommendations, environmental protection, studies on existing exposure situations, medical radiation protection today, science behind radiation doses, new developments in radiation effects, and ethics in radiation protection.

  15. Evaluation of water and sediment of the Graminha and Aguas da Serra streams in the city of Limeira (Sp-Brazil) by Synchrotron Radiation Total Reflection X-ray Fluorescence

    International Nuclear Information System (INIS)

    Moreira, Silvana; Fazza, Elizete Vieira

    2008-01-01

    The city of Limeira is located in the state of Sao Paulo, Brazil and has the second largest economy and demographic growth of the state. It comprises an expressive economy with industries in several productive sectors. The source of the Graminha and Aguas da Serra streams is located within the Limeira urban zone. The streams cross part of the rural zone and unite by draining into the Piracicaba River. It is possible that these basins suffer or have already suffered the impacts of environmental pollution caused by anthropogenic factors. Since the city has galvanization industries for the production of precious and semi-precious jewels as well as imitation jewelry, the concentration descriptions and interpretations of heavy metals in waters and sediments indicate anthropogenic influence and the dumping of these compounds into the Piracicaba River. The Synchrotron Radiation Total Reflection X-Ray Fluorescence (SR-TXRF) was used for determining the metals. All measurements were performed using a white beam of synchrotron radiation for excitation and a Ge hyperpure detector. Detection limits for water samples were 0.04 μg L -1 and in sediment samples 0.03 μg g -1 for Cu and Zn elements. In the water samples, concentrations higher than permissible as established by the Brazilian legislation (CONAMA) for Al, Fe, Zn, Cr, Ni, Cu and Pb, were observed. For sediment samples, values higher than quality reference values defined by the Brazilian legislation (CETESB) were verified for Cr, Zn, Cu, Ni and Pb

  16. Evaluation of water and sediment of the Graminha and Aguas da Serra streams in the city of Limeira (Sp-Brazil) by Synchrotron Radiation Total Reflection X-ray Fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana [University of Campinas, School of Civil Engineering, Architecture and Urban Design, P. O. Box 602, Zip Code 13083-852, Campinas, SP (Brazil)], E-mail: silvana@fec.unicamp.br; Fazza, Elizete Vieira [University of Campinas, School of Civil Engineering, Architecture and Urban Design, P. O. Box 602, Zip Code 13083-852, Campinas, SP (Brazil)], E-mail: fazzaelizete@yahoo.com

    2008-12-15

    The city of Limeira is located in the state of Sao Paulo, Brazil and has the second largest economy and demographic growth of the state. It comprises an expressive economy with industries in several productive sectors. The source of the Graminha and Aguas da Serra streams is located within the Limeira urban zone. The streams cross part of the rural zone and unite by draining into the Piracicaba River. It is possible that these basins suffer or have already suffered the impacts of environmental pollution caused by anthropogenic factors. Since the city has galvanization industries for the production of precious and semi-precious jewels as well as imitation jewelry, the concentration descriptions and interpretations of heavy metals in waters and sediments indicate anthropogenic influence and the dumping of these compounds into the Piracicaba River. The Synchrotron Radiation Total Reflection X-Ray Fluorescence (SR-TXRF) was used for determining the metals. All measurements were performed using a white beam of synchrotron radiation for excitation and a Ge hyperpure detector. Detection limits for water samples were 0.04 {mu}g L{sup -1} and in sediment samples 0.03 {mu}g g{sup -1} for Cu and Zn elements. In the water samples, concentrations higher than permissible as established by the Brazilian legislation (CONAMA) for Al, Fe, Zn, Cr, Ni, Cu and Pb, were observed. For sediment samples, values higher than quality reference values defined by the Brazilian legislation (CETESB) were verified for Cr, Zn, Cu, Ni and Pb.

  17. Microdosimetry: Reflections on Harald Rossi

    International Nuclear Information System (INIS)

    Kellerer, A.M.

    2002-01-01

    This and twelve previous Symposia reflect the evolution of microdosimetry, a field of research that has determined major new developments in radiation research, radiation protection, and radiology during the past four decades. The concepts of microdosimetry and its techniques were developed almost single handedly by H.H. Rossi. This memorial lecture outlines some of the ideas and some of the work of Harald Rossi that led to microdosimetry. It describes its major impact on radiobiology and, especially, its impact on studies with fast neutrons and on risk assessment. Microdosimetry was primarily designed as a tool for the elucidation of basic mechanisms of radiation action, but it has found its most important applications in the dosimetric measurement techniques that have become indispensable in radiation protection and in the dosimetry for radiation therapy. The advances of molecular biology are now providing new possibilities for a quantitative application of microdosimetry to radiobiology along the lines that Harald Rossi defined. (author)

  18. Challenging Narcissus, or Reflecting on Reflecting.

    Science.gov (United States)

    Achilles, C. M.

    The concept of reflective practice and teaching people to be reflective practitioners is examined. The document begins with a look at professional knowledge according to three prominent professionals in the educational administration field: Schon, Schein, and Achilles. "Reflective" strategies that could be incorporated into courses and…

  19. OSOAA: A Vector Radiative Transfer Model of Coupled Atmosphere-Ocean System for a Rough Sea Surface Application to the Estimates of the Directional Variations of the Water Leaving Reflectance to Better Process Multi-angular Satellite Sensors Data Over the Ocean

    Science.gov (United States)

    Chami, Malik; LaFrance, Bruno; Fougnie, Bertrand; Chowdhary, Jacek; Harmel, Tristan; Waquet, Fabien

    2015-01-01

    In this study, we present a radiative transfer model, so-called OSOAA, that is able to predict the radiance and degree of polarization within the coupled atmosphere-ocean system in the presence of a rough sea surface. The OSOAA model solves the radiative transfer equation using the successive orders of scattering method. Comparisons with another operational radiative transfer model showed a satisfactory agreement within 0.8%. The OSOAA model has been designed with a graphical user interface to make it user friendly for the community. The radiance and degree of polarization are provided at any level, from the top of atmosphere to the ocean bottom. An application of the OSOAA model is carried out to quantify the directional variations of the water leaving reflectance and degree of polarization for phytoplankton and mineral-like dominated waters. The difference between the water leaving reflectance at a given geometry and that obtained for the nadir direction could reach 40%, thus questioning the Lambertian assumption of the sea surface that is used by inverse satellite algorithms dedicated to multi-angular sensors. It is shown as well that the directional features of the water leaving reflectance are weakly dependent on wind speed. The quantification of the directional variations of the water leaving reflectance obtained in this study should help to correctly exploit the satellite data that will be acquired by the current or forthcoming multi-angular satellite sensors.

  20. The influence of the solid waste disposal areas in Campinas city, Sao Paulo state (Brazil) on water quality: determination of metals using synchrotron radiation total reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Oliveira, Bruna F.F.; Moreira, Silvana; Canteras, Felippe Benavente

    2013-01-01

    Among the many forms of waste disposal, landfills today are best suited to Brazilian conditions, this because their construction allows minimizing the negative effects of landfill gas and slurry produced. However, the confinement of pollutants from landfills is linked to its construction and operation and when the construction and/or is wrong they can endanger air, groundwater and surface waters qualities. Thus, the main objective of this study was to analyze the concentration of heavy metals in samples of groundwater, surface water and slurry coming from solid waste disposal locations in the city of Campinas, SP - Delta, Santa Barbara and Pirelli Landfills. The samples were analyzed at the Brazilian Synchrotron Light Laboratory using Synchrotron Radiation Total Reflection X-Ray Fluorescence technique (SR-TXRF). In Pirelli Landfill, the highest concentrations were observed in one of the wells located to downstream of the Landfill (in relation to the groundwater flux) - the monitoring well PM04, exceeding the intervention value defined by CETESB. For Santa Barbara landfill in one upstream monitoring well the concentrations of Ni, Mn, Pb and Cr, surpassed the maximum permissive values. The manganese in Landfill Delta showed to be higher in wells located downstream and 50% of the wells analyzed exceeded the maximum permissive value for groundwater samples. In the case of surface waters located in the vicinity of landfill sites, the metals that surpassed the maximum permissive values according the legislation in most of the points analyzed were Mn, Cu and Pb. For slurry samples collected in Delta Landfill, the average concentrations for Mn, Ni, Cu and Pb not exceeded the maximum permissive values during the period studied. Moreover for Santa Barbara the average concentration of Mn, Cu and Zn surpassed the permissive limits, as was observed for Mn in the Pirelli Landfill. (author)

  1. Reflectometry with synchrotron radiation

    International Nuclear Information System (INIS)

    Krumrey, Michael; Cibik, Levent; Fischer, Andreas; Gottwald, Alexander; Kroth, Udo; Scholze, Frank

    2014-01-01

    The measurement of the reflectivity for VUV, XUV, and X-radiation at the PTB synchrotron radiation sources is described. The corresponding data of the used beams are presented. Results of experiments on a Cu-Ni double-layer, SiO 2 , Si, and MgF 2 are presented. (HSI)

  2. Radiation Studies, Vol.10

    International Nuclear Information System (INIS)

    Nadareishvili, K.; Tsitskishvili, M.; Chankseliani, Z.; Gelashvili, K.; Mtskhoetadze, A.; Oniani, T.; Todua, F.; Vepkhoadze, N.; Zaalishvili, T.

    2002-01-01

    'Radiation studies' - is a periodical edition of Scientific Research Center of Radiobiology and Radiation Ecology of Georgian Academy of Sciences, Problem Council of Radiobiology of Georgian Academy of Sciences and Georgian Academy of Ecological Sciences. The 10th volume of 'Radiation studies' reflects activities of above-mentioned institutions during previous two years and contains 26 articles, from which 17 are within the scope of INIS

  3. Ultraviolet radiation

    International Nuclear Information System (INIS)

    Hawk, J.

    1986-01-01

    Ultraviolet radiation (UVR) from the sun or artificial sources is reflected or transmitted at the surface of the skin, about 5% of normally incident rays being directly reflected. The transmitted fraction is scattered, photochemically absorbed or dissipated as heat within the skin, or passes from it to contribute to the variable total amount of reflected and transmitted radiation. The UVR absorbers in skin are not definitely known, but DNA is a definite target and probably lipoprotein membranes, RNA, proteins, mucopolysaccharides, elastin and collagen. Photochemical or free radical damage to absorber or nearby organelles leads to pharmacological, ultrastructural, histological and clinical changes. Most frequent DNA damage is pyrimidine dimer formation, apparently inhibiting cell function and replication. This is largely enzymatically repaired in man in the dark by excision repair, post-replication repair and possible other enzymatic mechanisms, and at least in some organisms by light-induced photoreactivation repair. UVR exposure causes well recognized acute and chronic clinical syndromes in man. These are discussed in this paper

  4. Temperature-reflection I

    DEFF Research Database (Denmark)

    McGady, David A.

    2017-01-01

    -temperature path integrals for quantum field theories (QFTs) should be T-reflection invariant. Because multi-particle partition functions are equal to Euclidean path integrals for QFTs, we expect them to be T-reflection invariant. Single-particle partition functions though are often not invariant under T......In this paper, we revisit the claim that many partition functions are invariant under reflecting temperatures to negative values (T-reflection). The goal of this paper is to demarcate which partition functions should be invariant under T-reflection, and why. Our main claim is that finite...... that T-reflection is unrelated to time-reversal. Finally, we study the interplay between T-reflection and perturbation theory in the anharmonic harmonic oscillator in quantum mechanics and in Yang-Mills in four-dimensions. This is the first in a series of papers on temperature-reflections....

  5. Liberating Moral Reflection

    Science.gov (United States)

    Horell, Harold D.

    2013-01-01

    The author argues that if we are to foster life-giving and liberating moral reflection, we must first liberate moral reflection from distortions; specifically, from the distorting effects of moral insensitivity, destructive moral relativism, and confusions resulting from a failure to understand the dynamics of moral reflection. The author proposes…

  6. Radiation chemistry

    International Nuclear Information System (INIS)

    Rodgers, F.; Rodgers, M.A.

    1987-01-01

    The contents of this book include: Interaction of ionizing radiation with matter; Primary products in radiation chemistry; Theoretical aspects of radiation chemistry; Theories of the solvated electron; The radiation chemistry of gases; Radiation chemistry of colloidal aggregates; Radiation chemistry of the alkali halides; Radiation chemistry of polymers; Radiation chemistry of biopolymers; Radiation processing and sterilization; and Compound index

  7. Media for Reflection

    DEFF Research Database (Denmark)

    Knudsen, Morten

    2016-01-01

    This article develops the concept media for reflection in the interest of conceptualizing the interpretative frames that enable and limit reflection in management and leadership education. The concept ‘media for reflection’ allows us to conceptualize the social and cultural mediation of reflection...... without reducing reflection to an effect of the social structures and cultural norms in which it is embedded. Based on the developed theoretical framework, this article analyses how a renaissance ‘mirror for princes’ and contemporary research-based management education mediate reflection. The content...... of the mediations is analysed as well as the societal and organizational background. Furthermore, the means by which the two media enable and limit reflection in different ways is compared. Finally, the article discusses possible implications of the analysis in terms of management and leadership education....

  8. Principles of neutron reflection

    International Nuclear Information System (INIS)

    Felcher, G.P.

    1988-08-01

    Neutron reflection is perhaps the most developed branch of slow neutrons optics, which in itself is a direct consequence of the undulatory nature of the neutron. After reviewing the basic types of interactions (nuclear and magnetic) between neutrons and matter, the formalism is introduced to calculate the reflectivity from a sample composed of stacked flat layers and, inversely, to calculate the stacking from reflectivity measurements. Finally, a brief survey of the applications of neutron reflection is given, both in technology and in fundamental research. 32 refs., 6 figs

  9. Storage array reflection considerations

    International Nuclear Information System (INIS)

    Haire, M.J.; Jordan, W.C.; Taylor, R.G.

    1997-01-01

    The assumptions used for reflection conditions of single containers are fairly well established and consistently applied throughout the industry in nuclear criticality safety evaluations. Containers are usually considered to be either fully water-reflected (i.e. surrounded by 6 to 12 in. of water) for safety calculations or reflected by 1 in. of water for nominal (structural material and air) conditions. Tables and figures are usually available for performing comparative evaluations of containers under various loading conditions. Reflection considerations used for evaluating the safety of storage arrays of fissile material are not as well established

  10. Measurement and detection of radiation

    CERN Document Server

    Tsoulfanidis, Nicholas

    2015-01-01

    This fourth edition reflects recent major developments that have occurred in radiation detector materials, systems, and applications. It continues to provide the most practical and up-to-date introduction to radiation detector technology, proper measurement techniques, and analysis of results for engineers and scientists using radiation sources. New chapters emphasize the expanded use of radiation detection systems in nuclear non-proliferation, homeland security, and nuclear medicine. The book also discusses the correct ways to perform measurements following current health physics procedures.

  11. Clips supporting and spacing flanged sheets of reflective insulation

    International Nuclear Information System (INIS)

    Carr, R.W.

    1980-01-01

    This invention relates to clips, spacing and supporting flanged sheets of reflective insulation used to encase the main body and associated piping of nuclear reactors to minimize heat and radiation losses. (UK)

  12. Radiation and radiation protection

    International Nuclear Information System (INIS)

    Landfermann, H.H.; Solbach, C.

    1992-11-01

    The brochure explains the major types of radiation, the radiation sources, effects, uses, and risks, as well as the regulatory system adopted by the government in order to keep the risks as low as possible. (orig./DG) [de

  13. A climatology of visible surface reflectance spectra

    International Nuclear Information System (INIS)

    Zoogman, Peter; Liu, Xiong; Chance, Kelly; Sun, Qingsong; Schaaf, Crystal; Mahr, Tobias; Wagner, Thomas

    2016-01-01

    We present a high spectral resolution climatology of visible surface reflectance as a function of wavelength for use in satellite measurements of ozone and other atmospheric species. The Tropospheric Emissions: Monitoring of Pollution (TEMPO) instrument is planned to measure backscattered solar radiation in the 290–740 nm range, including the ultraviolet and visible Chappuis ozone bands. Observation in the weak Chappuis band takes advantage of the relative transparency of the atmosphere in the visible to achieve sensitivity to near-surface ozone. However, due to the weakness of the ozone absorption features this measurement is more sensitive to errors in visible surface reflectance, which is highly variable. We utilize reflectance measurements of individual plant, man-made, and other surface types to calculate the primary modes of variability of visible surface reflectance at a high spectral resolution, comparable to that of TEMPO (0.6 nm). Using the Moderate-resolution Imaging Spectroradiometer (MODIS) Bidirection Reflectance Distribution Function (BRDF)/albedo product and our derived primary modes we construct a high spatial resolution climatology of wavelength-dependent surface reflectance over all viewing scenes and geometries. The Global Ozone Monitoring Experiment–2 (GOME-2) Lambertian Equivalent Reflectance (LER) product provides complementary information over water and snow scenes. Preliminary results using this approach in multispectral ultraviolet+visible ozone retrievals from the GOME-2 instrument show significant improvement to the fitting residuals over vegetated scenes. - Highlights: • Our goals was visible surface reflectance for satellite trace gas measurements. • Captured the range of surface reflectance spectra through EOF analysis. • Used satellite surface reflectance products for each given scene to anchor EOFs. • Generated a climatology of time/geometry dependent surface reflectance spectra. • Demonstrated potential to

  14. Radiation measurement

    International Nuclear Information System (INIS)

    Go, Sung Jin; Kim, Seung Guk; No, Gyeong Seok; Park, Myeong Hwan; Ann, Bong Seon

    1998-03-01

    This book explains technical terms about radiation measurement, which are radiation, radiation quantity and unit such as prefix of international unit, unit for defence purposes of radiation, coefficient of radiation and interaction, kinds and principles of radiation detector, ionization chamber, G-M counter, G-M tube, proportional counter, scintillation detector, semiconductor radiation detector, thermoluminescence dosimeter, PLD, others detector, radiation monitor, neutron detector, calibration of radiation detector, statistics of counting value, activation analysis and electronics circuit of radiation detector.

  15. Dissenting in Reflective Conversations

    DEFF Research Database (Denmark)

    Bjørn, Pernille; Boulus, Nina

    2011-01-01

    Reflective monitoring of research practices is essential. However, we often lack formal training in the practices of doing action research, and descriptions of actual inquiry practice are seldom included in publications. Our aim is to provide a glimpse of self-reflective practices based on our...

  16. Self-Reflection

    DEFF Research Database (Denmark)

    Fausing, Bent

    2016-01-01

    will take a look at the establishing of the modern self and possibilities of self-reflection, too. My examples will be from the so-called dark-selfies and from a new selfie form, which merge the present with the previous progressing into the future. I will discuss the media reflections as loos and/or gain...

  17. Reflection: A Socratic approach.

    Science.gov (United States)

    Van Seggelen-Damen, Inge C M; Van Hezewijk, René; Helsdingen, Anne S; Wopereis, Iwan G J H

    2017-12-01

    Reflection is a fuzzy concept. In this article we reveal the paradoxes involved in studying the nature of reflection. Whereas some scholars emphasize its discursive nature, we go further and underline its resemblance to the self-biased dialogue Socrates had with the slave in Plato's Meno . The individual and internal nature of the reflection process creates difficulty for studying it validly and reliably. We focus on methodological issues and use Hans Linschoten's view of coupled systems to identify, analyze, and interpret empirical research on reflection. We argue that researchers and research participants can take on roles in several possible system couplings. Depending on who controls the manipulation of the stimulus, who controls the measuring instrument, who interprets the measurement and the response, different types of research questions can be answered. We conclude that reflection may be validly studied by combining different couplings of experimenter, manipulation, stimulus, participant, measurement, and response.

  18. High energy radiation detector

    International Nuclear Information System (INIS)

    Vosburgh, K.G.

    1975-01-01

    The high energy radiation detector described comprises a set of closely spaced wedge reflectors. Each wedge reflector is composed of three sides forming identical isoceles triangles with a common apex and an open base forming an equilateral triangle. The length of one side of the base is less than the thickness of the coat of material sensitive to high energy radiation. The wedge reflectors reflect the light photons spreading to the rear of the coat in such a way that each reflected track is parallel to the incident track of the light photon spreading rearwards. The angle of the three isosceles triangles with a common apex is between 85 and 95 deg. The first main surface of the coat of high energy radiation sensitive material is in contact with the projecting edges of the surface of the wedge reflectors of the reflecting element [fr

  19. Storage array reflection considerations

    International Nuclear Information System (INIS)

    Haire, M.J.; Jordan, W.C.; Taylor, R.G.

    1997-01-01

    The assumptions used for reflection conditions of single containers are fairly well established and consistently applied throughout the industry in nuclear criticality safety evaluations. Containers are usually considered to be either fully water reflected (i.e., surrounded by 6 to 12 in. of water) for safety calculations or reflected by 1 in. of water for nominal (structural material and air) conditions. Tables and figures are usually available for performing comparative evaluations of containers under various loading conditions. Reflection considerations used for evaluating the safety of storage arrays of fissile material are not as well established. When evaluating arrays, it has become more common for analysts to use calculations to demonstrate the safety of the array configuration. In performing these calculations, the analyst has considerable freedom concerning the assumptions made for modeling the reflection of the array. Considerations are given for the physical layout of the array with little or no discussion (or demonstration) of what conditions are bounded by the assumed reflection conditions. For example, an array may be generically evaluated by placing it in a corner of a room in which the opposing walls are far away. Typically, it is believed that complete flooding of the room is incredible, so the array is evaluated for various levels of water mist interspersed among array containers. This paper discusses some assumptions that are made regarding storage array reflection

  20. Model for the filamentary structure in the pleiades reflection nebulosity

    International Nuclear Information System (INIS)

    Arny, T.

    1977-01-01

    It is suggested that the filamentary structure in the Pleiades reflection nebula is caused by shearing of dust clumps in an interstellar cloud moving through the star cluster. Radiation pressure flattens a dust clump and causes it to flow around a star, forming a shell. The anisotropy of the radiation field shears clumps into long streamers

  1. Extreme Ultraviolet Bragg mirrors with suppressed infrared reflectivity properties

    NARCIS (Netherlands)

    Medvedev, Viacheslav; Yakshin, Andrey; Louis, Eric; van de Kruijs, Robbert Wilhelmus Elisabeth; van den Boogaard, Toine; Krivtsun, V.M.; Yakinun, A.M.; Bijkerk, Frederik

    2013-01-01

    Many optical applications demand high reflectivity in a particular wavelength range while simultaneously requiring suppression of radiation outside this range. Such parasitic radiation can for instance lead to image distortions in imaging applications or poor signal-noise ratios in spectroscopy. The

  2. Extreme Ultraviolet Bragg mirrors with suppressed infrared reflectivity properties

    NARCIS (Netherlands)

    Medvedev, Viacheslav; Yakshin, Andrey; Louis, Eric; van de Kruijs, Robbert Wilhelmus Elisabeth; van den Boogaard, Toine; Krivtsun, V.M.; Yakunin, A.M.; Bijkerk, Frederik

    2012-01-01

    Many optical applications demand high reflectivity in a particular wavelength range while simultaneously requiring suppression of radiation outside this range. Such parasitic radiation can for instance lead to image distortions in imaging applications or poor signal-noise ratios in spectroscopy. The

  3. The Reflective Foundation

    DEFF Research Database (Denmark)

    Lunde Jørgensen, Ida

    Private foundations and cultural philanthropy by élites is viewed with increasing skepticism in recent years, begging the question of the extent to which foundations reflect on their role vis a vis wider societal norms. Through the prism of the New Carlsberg Foundation, financed by the brewery...... Carlsberg A/S, the paper seeks to elucidate the way in which one culturally significant foundation from Denmark has reflected on - and legitimated - its work and investments at critical moments in the past decades. The paper indicates a foundation with a high degree of reflection on the wider societal...

  4. Reflection technique for thermal mapping of semiconductors

    Science.gov (United States)

    Walter, Martin J.

    1989-06-20

    Semiconductors may be optically tested for their temperatures by illuminating them with tunable monochromatic electromagnetic radiation and observing the light reflected off of them. A transition point will occur when the wavelength of the light corresponds with the actual band gap energy of the semiconductor. At the transition point, the image of the semiconductor will appreciably darken as the light is transmitted through it, rather than being reflected off of it. The wavelength of the light at the transition point corresponds to the actual band gap energy and the actual temperature of the semiconductor.

  5. X-ray reflectivity and surface roughness

    International Nuclear Information System (INIS)

    Ocko, B.M.

    1988-01-01

    Since the advent of high brightness synchrotron radiation sources there has been a phenomenal growth in the use of x-rays as a probe of surface structure. The technique of x-ray reflectivity is particularly relevant to electrochemists since it is capable of probing the structure normal to an electrode surface in situ. In this paper the theoretical framework for x-ray reflectivity is reviewed and the results from previous non-electrochemistry measurements are summarized. These measurements are from the liquid/air interface (CCl 4 ), the metal crystal vacuum interface (Au(100)), and from the liquid/solid interface(liquid crystal/silicon). 34 refs., 5 figs

  6. Effect of Fresnel Reflectivity in a Spherical Turbid Medium

    CERN Document Server

    Elghazaly, A

    2003-01-01

    Radiative transfer problem for anisotropic scattering in a spherical homogeneous, turbid medium with angular dependent (specular) reflecting boundary is solved using the pomraning-Eddington approximation method. The angular dependent reflectivity of the boundary is considered as Fresnel's reflection probability function. The partial heat flux is calculated with anisotropic scattering through a homogeneous solid sphere. our results are compared with the available data and give an excellent agreement.

  7. Effect of Fresnel Reflectivity in a Spherical Turbid Medium

    International Nuclear Information System (INIS)

    Elghazaly, A.; Attia, M.T.

    2003-01-01

    Radiative transfer problem for anisotropic scattering in a spherical homogeneous, turbid medium with angular dependent (specular) reflecting boundary is solved using the pomraning-Eddington approximation method. The angular dependent reflectivity of the boundary is considered as Fresnel's reflection probability function. The partial heat flux is calculated with anisotropic scattering through a homogeneous solid sphere. our results are compared with the available data and give an excellent agreement

  8. Seasonal soybean crop reflectance

    Science.gov (United States)

    Lemaster, E. W. (Principal Investigator); Chance, J. E.

    1983-01-01

    Data are presented from field measurements of 1980 including 5 acquisitions of handheld radiometer reflectance measurements, 7 complete sets of parameters for implementing the Suits mode, and other biophysical parameters to characterize the soybean canopy. LANDSAT calculations on the simulated Brazilian soybean reflectance are included along with data collected during the summer and fall on 1981 on soybean single leaf optical parameters for three irrigation treatments. Tests of the Suits vegetative canopy reflectance model for the full hemisphere of observer directions as well as the nadir direction show moderate agreement for the visible channels of the MSS and poor agreement in the near infrared channel. Temporal changes in the spectral characteristics of the single leaves were seen to occur as a function of maturity which demonstrates that the absorptance of a soybean single leaf is more a function of thetransmittancee characteristics than the seasonally consistent single leaf reflectance.

  9. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  10. Wave reflections from breakwaters

    OpenAIRE

    Dickson, William S.

    1994-01-01

    A new method is presented for estimating the reflection of a random, multi-directional sea from a coastal structure. The technique is applicable to an array of wave gauges of arbitrary geometry deployed seaward of the reflector. An expansion for small oblique wave incidence angles is used to derive an approximate relationship between measured array cross-spectra and a small number of parameters that describe the incident wave properties and the reflectivity of the structure. Model tests with ...

  11. Thoughts on Reflection (Editorial

    Directory of Open Access Journals (Sweden)

    Denise Koufogiannakis

    2010-06-01

    Full Text Available There has been some acknowledgement in the published literature that reflection is a crucial element of the evidence based library and information practice (EBLIP model we have adopted (Booth 2004, 2006; Grant 2007; Helliwell 2007. As we work through a problem and try to incorporate the best available evidence into our decision making, reflection is required at several stages, including the very identification of the problem through to our assessment of the process itself and what we have learned in order to inform future practice. However, reflection and reflective writing have not fully been integrated into the process we espouse, and very little has been done to look more closely at this element of the model and how it can be integrated into professional learning.In a recently published research article, Sen (2010 confirms the relationship between reflection and several aspects of professional practice. These include critical review and decision making, two aspects that are tied closely to the evidence based process. Sen notes: Students were more likely to show evidence of learning, self‐development, the ability to review issues crucially, awareness of their own mental functions, ability to make decision [sic] and being empowered when they had mastered the art of reflective practice and the more deeply analytical reflective writing. (p.84 EBLIP (the journal tries to incorporate elements of reflection within the articles we publish. While we clearly believe in the need for our profession to do quality research and publish that research so that it can be accessible to practitioners, we also know that research cannot be looked at in isolation. Our evidence summaries are one way of reflecting critically on previously published research, and in the same vein, our classics bring older research studies back to the foreground. This work needs to continue to be discussed and looked at for its impact on our profession.More directly, the Using

  12. Radiative heat exchange between surfaces

    International Nuclear Information System (INIS)

    Yener, Y.; Yuncu, H.

    1987-01-01

    The geometrical features of radiative heat exchange between surfaces are discussed first by developing various radiation shape factor relations. The governing equations for enclosures with diffusely emitting and diffusely reflecting surfaces, as well as the equations for enclosures with gray surfaces having specular component of reflectivity are introduced next. Finally, a simplified model for enclosures with isothermal surfaces under the assumption of uniform radiosity over the surfaces is discussed, and various working relations for different conditions are presented

  13. Creation, Identity and Reflection

    Directory of Open Access Journals (Sweden)

    Alina Beatrice Cheşcă

    2015-05-01

    Full Text Available The paper “Creation, Identity and Reflection” approaches the identification in the “mirror” of reality with creation, in other words seeking the authors’ identity in the reflected images. Reflection means attempting to find oneself, the mirror being the main principle of creation. Many characters become interesting only when they step into the world beyond the mirror, when their faces are doubled by the other self or when their selves are returned by other characters. The narcissistic concept of the mirror, i.e. the reflection in the mirror and the representation of the mirror itself, is a recurrent one in literature, but the reflection of the self which is not the self (as it is a reflection does not necessarily appear in a mirror or in a photograph or portrait. Sometimes, the not-self is returned to the self by another person or character. As far as Oscar Wilde’s theories are concerned, the main idea is that people are interesting for their masks, not for their inner nature. What Wilde calls “inner nature” is the characters’ un-reflected self and the mask is the reflection, the self in the mirror. Some characters’ relationships develop within a fiction that they dramatically try to preserve and protect with the risk of suffering. They refuse to take off the masks which define them in the others’ minds and hearts; the narcissistic individuals (both artists and characters seek and love their own image which they project upon facts, thus creating a fictive realm.

  14. Radiation Protection Dosimetry

    International Nuclear Information System (INIS)

    Kramer, H.M.; Schnuer, K.

    1992-01-01

    The contributions presented during the seminar provided clear evidence that radiation protection of the patient plays an increasingly important role for manufacturers of radiological equipment and for regulatory bodies, as well as for radiologists, doctors and assistants. The proceedings of this seminar reflect the activities and work in the field of radiation protection of the patient and initiate further action in order to harmonize dosimetric measurements and calculations, to ameliorate education and training, to improve the technical standards of the equipment and to give a push to a more effective use of ionising radiation in the medical sector

  15. Dragonflies | Overview | Publications | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    This lacuna is largely due to the lack of user-friendly field guides for amateur naturalists and students. As an initiative ... The novelty of the book is provision of common English names of all species. The first edition ... Access To [All] Knowledge.

  16. Dragonflies and Damselflies of Peninsular India

    Indian Academy of Sciences (India)

    K A Subramaniam

    Studying Odonates. .... efforts to conserve, and prudently use, India's rich heritage of biodiversity. This is the ... Thanks to the work of Fraser, the Indian odonate fauna is well documented in ... English names to families and species of odonates.

  17. A fatal poisoning involving Bromo-Dragonfly

    DEFF Research Database (Denmark)

    Andreasen, Mette Findal

    hallucinogen, only slightly less potent than LSD. In the present case from Denmark an 18-year-old woman was found dead one morning in October 2007. The previous evening she and her boyfriend had both ingested a hallucinogen LSD-like liquid. A medico-legal autopsy was performed on the deceased. Liver, blood...

  18. Properties of interstellar dust in reflection nebulae

    International Nuclear Information System (INIS)

    Sellgren, K.

    1988-01-01

    Observations of interstellar dust in reflection nebulae are the closest analog in the interstellar medium to studies of cometary dust in our solar system. The presence of a bright star near the reflection nebula dust provides the opportunity to study both the reflection and emission characteristics of interstellar dust. At 0.1 to 1 micrometer, the reflection nebula emission is due to starlight scattered by dust. The albedo and scattering phase function of the dust is determined from observations of the scattered light. At 50 to 200 micrometers, thermal emission from the dust in equilibrium with the stellar radiation field is observed. The derived dust temperature determines the relative values of the absorption coefficient of the dust at wavelengths where the stellar energy is absorbed and at far infrared wavelengths where the absorbed energy is reradiated. These emission mechanisms directly relate to those seen in the near and mid infrared spectra of comets. In a reflection nebula the dust is observed at much larger distances from the star than in our solar system, so that the equilibrium dust temperature is 50 K rather than 300 K. Thus, in reflection nebulae, thermal emission from dust is emitted at 50 to 200 micrometer

  19. Snow, ice and solar radiation

    NARCIS (Netherlands)

    Kuipers Munneke, P.

    2009-01-01

    The snow-covered ice sheets of Antarctica and Greenland reflect most of the incoming solar radiation. The reflectivity, commonly called the albedo, of snow on these ice sheets has been observed to vary in space and time. In this thesis, temporal and spatial changes in snow albedo is found to depend

  20. Synchrotron radiation

    International Nuclear Information System (INIS)

    Pattison, P.; Quinn, P.

    1990-01-01

    This report details the activities in synchrotron radiation and related areas at Daresbury Laboratory during 1989/90. The number and scope of the scientific reports submitted by external users and in-house staff is a reflection of the large amount of scheduled beamtime and high operating efficiency achieved at the Synchrotron Radiation Source (SRS) during the past year. Over 4000 hours of user beam were available, equivalent to about 80% of the total scheduled time. Many of the reports collected here illustrate the increasing technical complexity of the experiments now being carried out at Daresbury. Provision of the appropriate technical and scientific infrastructure and support is a continuing challenge. The development of the Materials Science Laboratory together with the existing Biological Support Laboratory will extend the range of experiments which can be carried out on the SRS. This will particularly facilitate work in which the sample must be prepared or characterised immediately before or during an experiment. The year 1989/90 has also seen a substantial upgrade of several stations, especially in the area of x-ray optics. Many of the advantages of the High Brightness Lattice can only be exploited effectively with the use of focusing optics. As the performance of these stations improves, the range of experiments which are feasible on the SRS will be extended significantly. (author)

  1. Biology Reflective Assessment Curriculum

    Science.gov (United States)

    Bayley, Cheryl Ann

    Often students and educators view assessments as an obligation and finality for a unit. In the current climate of high-stakes testing and accountability, the balance of time, resources and emphasis on students' scores related to assessment have been slanted considerably toward the summative side. This tension between assessment for accountability and assessment to inform teaching strains instruction and educators' ability to use that information to design learning opportunities that help students develop deeper conceptual understanding. A substantive body of research indicates that formative and reflective assessment can significantly improve student learning. Biology Reflective Assessment Curriculum (BRAC) examines support provided for high school science students through assessment practices. This investigation incorporates the usage of reflective assessments as a guiding practice for differentiated instruction and student choice. Reflective assessment is a metacognitive strategy that promotes self-monitoring and evaluation. The goals of the curriculum are to promote self-efficacy and conceptual understanding in students learning biology through developing their metacognitive awareness. BRAC was implemented in a high school biology classroom. Data from assessments, metacognitive surveys, self-efficacy surveys, reflective journals, student work, a culminating task and field notes were used to evaluate the effectiveness of the curriculum. The results suggest that students who develop their metacognitive skills developed a deeper conceptual understanding and improved feelings of self-efficacy when they were engaged in a reflective assessment unit embedded with student choice. BRAC is a tool for teachers to use assessments to assist students in becoming metacognitive and to guide student choice in learning opportunities.

  2. Self-Reflection

    DEFF Research Database (Denmark)

    Fausing, Bent

    2018-01-01

    Reflecting has a double meaning, mirroring and thinking. The seminar will investigate how these two meanings intervene in each other. As we perceive we are already in pre-refectory state, and thinking involves a lot of not only thoughts, but also of senses and sensing, wherefrom our thoughts star...

  3. Worship, Reflection, Empirical Research

    OpenAIRE

    Ding Dong,

    2012-01-01

    In my youth, I was a worshipper of Mao Zedong. From the latter stage of the Mao Era to the early years of Reform and Opening, I began to reflect on Mao and the Communist Revolution he launched. In recent years I’ve devoted myself to empirical historical research on Mao, seeking the truth about Mao and China’s modern history.

  4. Wave Reflection Model Tests

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Larsen, Brian Juul

    The investigation concerns the design of a new internal breakwater in the main port of Ibiza. The objective of the model tests was in the first hand to optimize the cross section to make the wave reflection low enough to ensure that unacceptable wave agitation will not occur in the port. Secondly...

  5. Reflections on 21 years

    International Nuclear Information System (INIS)

    Eklund, S.; Mandel, H.; Teller, E.

    1977-01-01

    Personal reflections after twenty one years of nuclear power are presented by a number of those who were international figures in the nuclear energy field during that period. Lessons learnt, achievements, prospects and predictions for the future are discussed in eleven brief surveys. (U.K.)

  6. Reflection by Porro Prisms

    Science.gov (United States)

    Greenslade, Thomas B.

    2010-04-01

    Students all know that reflection from a plane mirror produces an image that is reversed right to left and so cannot be read by anyone but Leonardo da Vinci, who kept his notes in mirror writing. A useful counter-example is the Porro prism, which produces an image that is not reversed.

  7. Value reflected health education

    DEFF Research Database (Denmark)

    Wistoft, Karen; Nordentoft, Helle Merete

    2011-01-01

    This article examines the impact of a value-reflected approach in health education by demonstrating the nature of professional competence development connected to this approach. It is based on findings from two three-year health educational development projects carried out by school health nurses...... develop pedagogical competences in health education improving school childrens’ health....

  8. Reflection on Political Representation

    DEFF Research Database (Denmark)

    Kusche, Isabel

    2017-01-01

    This article compares how Members of Parliament in the United Kingdom and Ireland reflect on constituency service as an aspect of political representation. It differs from existing research on the constituency role of MPs in two regards. First, it approaches the question from a sociological viewp...

  9. Onward: Reflections on Mentoring

    Science.gov (United States)

    Williams, Kimberley Buster

    2018-01-01

    The author has been blessed with great mentors throughout her career. When she was invited to participate in the Leadership University of Mary Washington (UMW), a mentoring program at her institution, she did not hesitate to say yes. In this article, the author shares her reflections on mentoring.

  10. Interferometric reflection moire

    Science.gov (United States)

    Sciammarella, Cesar A.; Combell, Olivier

    1995-06-01

    A new reflection moire technique is introduced in this paper. The basic equations that relate the measurement of slopes to the basic geometric and optical parameters of the system are derived. The sensitivity and accuracy of the method are discussed. Examples of application to the study of silicon wafers and electronic chips are given.

  11. Reflection on robotic intelligence

    NARCIS (Netherlands)

    Bartneck, C.

    2006-01-01

    This paper reflects on the development or robots, both their physical shape as well as their intelligence. The later strongly depends on the progress made in the artificial intelligence (AI) community which does not yet provide the models and tools necessary to create intelligent robots. It is time

  12. Reflections on "La Esperanza"

    Science.gov (United States)

    Cortez, Anita

    2007-01-01

    The author was recently asked to reflect on her "educational journey." As far as she can remember she has been hungry to learn. A friend once described her as having "hambres atrasadas," which he described as a kind of "hunger nipping at her heels." It goes back, of course, to her parents: Her father's and her early…

  13. Reflecting on Writing Autobiography

    Science.gov (United States)

    Begg, Andy

    2011-01-01

    The following reflections relate to the reasons for and an approach to an autobiographic task, the notions that underpin it, and some thoughts about the quality and value of such a project. The focus was on the ways one views curriculum change over time; and the intention was to provide an example that others may sense as either familiar or at…

  14. Reflections on the Field.

    Science.gov (United States)

    Kauffman, James M.

    2003-01-01

    Reflections on the field of special education offer six ideas: (1) the value of science; (2) the continuing value of separate and special education for some students; (3) the continuing importance of prevention; (4) the importance of academic instruction; (5) the importance of social justice for the poor; and (6) a renewed emphasis on human…

  15. Reflections, 15 Years Later

    Science.gov (United States)

    Knox, George

    2016-01-01

    George Knox reflects on his 15-year career as president of Labette Community College in Parsons, Kansas. Knox writes that, as a first-time president coming into a brand new system, he was very fortunate to have many seasoned presidents and mentors in Kansas and from the American Association of Community Colleges' (AACC) Presidents Academy. He says…

  16. Energy loss from internal reflection off metal layers on glass

    Science.gov (United States)

    McDowell, M. W.; Bezuidenhout, D. F.; Klee, H. W.; Theron, E.

    1983-12-01

    The reflection characteristics of metal layers are considered for the situation where the electromagnetic radiation is incident from the glass side. Theoretical and measured reflectance values are presented which indicate that for some metals the reflection has a strong dependence on the refractive index of the incident medium. Some examples are given of recent cases where the above results were an important consideration in the choice of the metallic reflecting material. These results indicate that aluminium should not be automatically considered the best choice for the visible region nor gold for the infra-red.

  17. Reflection of oblique electron thermal modes in an inhomogeneous plasma

    International Nuclear Information System (INIS)

    Ohnuma, T.; Watanabe, T.; Sanuki, H.

    1980-04-01

    In an inhomogeneous magnetoplasma, reflection of an oblique electron thermal mode radiated from a local source is investigated experimentally and theoretically near the electron plasma frequency layer. The experimental observation of reflection in the lower plasma density region than the f sub(p)-layer is found to be in qualitative accord with the theoretical reflection, which is obtained from a kinetic theory in an inhomogeneous magnetoplasma. The reflection of the thermal mode is also compared with that of an electromagnetic mode at the f sub(p)-layer. (author)

  18. Ionizing radiation, radiation sources, radiation exposure, radiation effects. Pt. 2

    International Nuclear Information System (INIS)

    Schultz, E.

    1985-01-01

    Part 2 deals with radiation exposure due to artificial radiation sources. The article describes X-ray diagnosis complete with an analysis of major methods, nuclear-medical diagnosis, percutaneous radiation therapy, isotope therapy, radiation from industrial generation of nucler energy and other sources of ionizing radiation. In conclusion, the authors attempt to asses total dose, genetically significant dose and various hazards of total radiation exposure by means of a summation of all radiation impacts. (orig./WU) [de

  19. Being a reflective teacher——reflection on group management

    Institute of Scientific and Technical Information of China (English)

    Pan; Lehui

    2015-01-01

    <正>Introduction According to Pollard and Triggs(1997),reflective teaching is a process through which the capacity to make such professional judgments can be developed and maintained.Then what is a reflective teacher?Reflective teacher is someone who reflects systematically on her practice in a constant attempt to improve

  20. Ethical reflection and psychotherapy.

    Science.gov (United States)

    Vyskocilová, Jana; Prasko, Jan

    2013-01-01

    Theories of ethics and ethical reflection may be applied to both theory and practice in psychotherapy. There is a natural affinity between ethics and psychotherapy. Psychotherapy practice is concerned with human problems, dilemmas and emotions related to both one's own and other people's values. Ethics is also concerned with dilemmas in human thinking and with how these dilemmas reflect other individuals' values. Philosophical reflection itself is not a sufficient basis for the ethics of psychotherapy but it may aid in exploring attitudes related to psychotherapy, psychiatry and health care. PubMed, Web of Science and Scopus databases were searched for articles containing the keywords "psychotherapy", "ethics", "therapeutic relationship" and "supervision". The search was conducted by repeating the terms in various combinations without language or time restrictions. Also included were data from monographs cited in reviews. The resulting text is a review with conclusions concerning ethical aspects of psychotherapy. The ability to behave altruistically, sense for justice and reciprocity and mutual help are likely to be genetically determined as dispositions to be later developed by upbringing or to be formed or deformed by upbringing. Early experiences lead to formation of ethical attitudes which are internalized and then applied to both one's own and other people's behavior. Altruistic behavior has a strong impact on an individual's health and its acceptance may positively influence the pathophysiological mechanisms underlying numerous diseases. Ethical theory and reflection, however, may be applied to both theory and practice of psychotherapy in a conscious, targeted and thoughtful manner. In everyday practice, psychotherapists and organizations must necessarily deal with conscious conflicts between therapeutic possibilities, clients' wishes, their own as well as clients' ideas and the real world. Understanding one's own motives in therapy is one of the aims of a

  1. Evaluating Multispectral Snowpack Reflectivity With Changing Snow Correlation Lengths

    Science.gov (United States)

    Kang, Do Hyuk; Barros, Ana P.; Kim, Edward J.

    2016-01-01

    This study investigates the sensitivity of multispectral reflectivity to changing snow correlation lengths. Matzler's ice-lamellae radiative transfer model was implemented and tested to evaluate the reflectivity of snow correlation lengths at multiple frequencies from the ultraviolet (UV) to the microwave bands. The model reveals that, in the UV to infrared (IR) frequency range, the reflectivity and correlation length are inversely related, whereas reflectivity increases with snow correlation length in the microwave frequency range. The model further shows that the reflectivity behavior can be mainly attributed to scattering rather than absorption for shallow snowpacks. The largest scattering coefficients and reflectivity occur at very small correlation lengths (approximately 10(exp -5 m) for frequencies higher than the IR band. In the microwave range, the largest scattering coefficients are found at millimeter wavelengths. For validation purposes, the ice-lamella model is coupled with a multilayer snow physics model to characterize the reflectivity response of realistic snow hydrological processes. The evolution of the coupled model simulated reflectivities in both the visible and the microwave bands is consistent with satellite-based reflectivity observations in the same frequencies. The model results are also compared with colocated in situ snow correlation length measurements (Cold Land Processes Field Experiment 2002-2003). The analysis and evaluation of model results indicate that the coupled multifrequency radiative transfer and snow hydrology modeling system can be used as a forward operator in a data-assimilation framework to predict the status of snow physical properties, including snow correlation length.

  2. Atoms, radiation, and radiation protection

    International Nuclear Information System (INIS)

    Turner, J.E.

    1986-01-01

    This book describes basic atomic and nuclear structure, the physical processes that result in the emission of ionizing radiations, and external and internal radiation protection criteria, standards, and practices from the standpoint of their underlying physical and biological basis. The sources and properties of ionizing radiation-charged particles, photons, and neutrons-and their interactions with matter are discussed in detail. The underlying physical principles of radiation detection and systems for radiation dosimetry are presented. Topics considered include atomic physics and radiation; atomic structure and radiation; the nucleus and nuclear radiation; interaction of heavy charged particles with matter; interaction of beta particles with matter; phenomena associated with charged-particle tracks; interaction of photons with matter; neutrons, fission and criticality; methods of radiation detection; radiation dosimetry; chemical and biological effects of radiation; radiation protection criteria and standards; external radiation protection; and internal dosimetry and radiation protection

  3. Natural radiation

    International Nuclear Information System (INIS)

    Feliciano, Vanusa Maria Delage

    2016-01-01

    Cosmic radiation, as well as cosmogenic radiation, terrestrial radiation, radon and thorium are introduced in this chapter 3. The distribution of natural radiation sources is treated, where the percentage distribution of the contribution relative to exposure to radiation from natural and artificial sources is also included

  4. Bragg reflection program

    International Nuclear Information System (INIS)

    Lynn, J.W.

    This user's guide to the Bragg Reflection Program (BRP) is in the nature of an informal report. The general purpose of BRP is to scan a series of Bragg reflections automatically in order to obtain profiles and integrated intensities. The program is used in conjunction with the SUPERVISOR and READ packages, and the procedures for using it are similar to those for the Triple-Axis Control program. All the general features of the system, SUPERVISOR and READ packages as described in the Spectrometer Control Systems User's Guide are preserved. The presentation assumes that the reader is familiar with these. Sections are given on the READ package, execution and use, error messages, and output. A few sample problems are shown. (1 figure) (U.S.)

  5. Reflections on Active Networking

    Science.gov (United States)

    2005-01-01

    with a Software Switch for Active Networks ”. We had initially called the project “ SoftSwitch ”, but after some concerns David Farber raised that this...Reflections on Active Networking Jonathan M. Smith CIS Department, University of Pennsylvania jms@cis.upenn.edu Abstract Interactions among...telecommunications networks , computers, and other peripheral devices have been of interest since the earliest distributed computing systems. A key

  6. Clinical linguistics: conversational reflections.

    Science.gov (United States)

    Crystal, David

    2013-04-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference participants during that time.

  7. Effect of reflective surfaces on a greenhouse lettuce crop

    Energy Technology Data Exchange (ETDEWEB)

    Warman, P.R.; Mayhew, W.J.

    1979-01-01

    The Canadian greenhouse industry is an important segment of horticultural production, providing employment for thousands of people. Continuing increases in the costs of conventional fuel supplies, however, has placed the industry in some jeopardy since the cost of heating during the winter months is also escalating. In response to this problem the Brace Research Institute has developed a single roofed greenhouse designed to capture and store the sun's energy, and to increase the amount of downward solar radiation inside the greenhouse through the use of specularly-reflecting back and side walls. The research investigated the effect of a reflective surface on plant growth, development, and nutritional uptake during fall and the early months of winter. The inside walls of the greenhouse were lined with aluminized polyester to act as a reflective surface and flat black roofing felt paper to provide a non-reflecting surface. Grand Rapids Forcing lettuce was planted from seed into a peat-vermiculite bed and total solar radiation was monitored on the horizontal. Over the duration of the experiment, the reflective side of the greenhouse received more than twice as much solar radiation as the non-reflective side leading to significantly larger plant yields on the reflective side. There were no significant differences in the uptake of the plant macronutrients, N, P, K, Ca, and Mg.

  8. Polarizer reflectivity variations

    International Nuclear Information System (INIS)

    Ozarski, R.G.; Prior, J.

    1980-01-01

    On Shiva the beam energy along the chain is monitored using available reflections and/or transmission through beam steering, splitting, and polarizing optics without the intrusion of any additional glass for diagnostics. On the preamp table the diagnostic signal is obtained from the signal transmitted through turning mirrors. At the input of each chain the signal is obtained from the transmission through one of the mirrors used for the chain input alignment sensor (CHIP). At the chain output the transmission through the final turning mirror is used. These diagnostics have proved stable and reliable. However, one of the prime diagnostic locations is at the output of the beta rod. The energy at this location is measured by collecting small reflections from the last polarizer surface of the beta Pockels cell polarizer package. Unfortunately, calibration of this diagnostic has varied randomly, seldom remaining stable for a week or more. The cause of this fluctuation has been investigated for the past year and'it has been discovered that polarizer reflectivity varies with humidity. This report will deal with the possible causes that were investigated, the evidence that humidity is causing the variation, and the associated mechanism

  9. Reflection Revisited: The Class Collage

    Science.gov (United States)

    Sommers, Jeff

    2011-01-01

    Through the regular use of what Donald Schon has termed reflection-in-action and reflection-on-action, students can learn to improve their "reflection-in-presentation," in Kathleen Blake Yancey's term. Students are often asked to do this type of reflection-in-presentation as a capstone to first-year or basic writing courses. However, a number of…

  10. Reflection as Self-Assessment

    Science.gov (United States)

    Pappas, Marjorie L.

    2010-01-01

    In this article, the author discusses how reflection can be used as self-assessment. Reflection involves not only thinking about a learning experience, but also questioning parts of the experience. Reflection is thinking about what one knows from the learning experience, what one might do differently the next time. Reflection is wondering about…

  11. Radiation enteritis

    International Nuclear Information System (INIS)

    Ochsner, S.F.; Head, L.H.

    1973-01-01

    A comprehensive review of radiation enteritis is presented. Experience in clinical radiation therapy has indicated that the small bowel is the segment of the alimentary tract that is most susceptible to radiation damage. (U.S.)

  12. Radiation monitor

    International Nuclear Information System (INIS)

    Pao, C.T.; Green, W.K.

    1978-01-01

    A system for indicating radiation from a radioactive fluid such as a gas wherein simultaneous indications of the activity concentration of radioactivity of the gas, the radiation dose rate and average energy of the radiation are provided

  13. Radiation protection

    International Nuclear Information System (INIS)

    Ures Pantazi, M.

    1994-01-01

    This work define procedures and controls about ionizing radiations. Between some definitions it found the following topics: radiation dose, risk, biological effects, international radioprotection bodies, workers exposure, accidental exposure, emergencies and radiation protection

  14. Radiation sickness

    Science.gov (United States)

    ... exposure to ionizing radiation. There are two main types of radiation: nonionizing and ionizing. Nonionizing radiation comes in the form of light, radio waves, microwaves and radar. These forms usually don't cause tissue damage. ...

  15. Ionizing radiation

    International Nuclear Information System (INIS)

    Kruger, J.

    1989-01-01

    Ionizing radiation results in biological damage that differs from other hazardous substances and is highly dangerous to man. Ionizing radiation cannot be perceived by man's sense organs and the biological damage cannot be detected immediately afterwards (except in very high doses). Every human being is exposed to low doses of radiation. The structure of the atom; sources of ionizing radiation; radiation units; biological effects; norms for radiation protection; and the national control in South Africa are discussed. 1 fig., 5 refs

  16. Seismic reflection imaging, accounting for primary and multiple reflections

    Science.gov (United States)

    Wapenaar, Kees; van der Neut, Joost; Thorbecke, Jan; Broggini, Filippo; Slob, Evert; Snieder, Roel

    2015-04-01

    Imaging of seismic reflection data is usually based on the assumption that the seismic response consists of primary reflections only. Multiple reflections, i.e. waves that have reflected more than once, are treated as primaries and are imaged at wrong positions. There are two classes of multiple reflections, which we will call surface-related multiples and internal multiples. Surface-related multiples are those multiples that contain at least one reflection at the earth's surface, whereas internal multiples consist of waves that have reflected only at subsurface interfaces. Surface-related multiples are the strongest, but also relatively easy to deal with because the reflecting boundary (the earth's surface) is known. Internal multiples constitute a much more difficult problem for seismic imaging, because the positions and properties of the reflecting interfaces are not known. We are developing reflection imaging methodology which deals with internal multiples. Starting with the Marchenko equation for 1D inverse scattering problems, we derived 3D Marchenko-type equations, which relate reflection data at the surface to Green's functions between virtual sources anywhere in the subsurface and receivers at the surface. Based on these equations, we derived an iterative scheme by which these Green's functions can be retrieved from the reflection data at the surface. This iterative scheme requires an estimate of the direct wave of the Green's functions in a background medium. Note that this is precisely the same information that is also required by standard reflection imaging schemes. However, unlike in standard imaging, our iterative Marchenko scheme retrieves the multiple reflections of the Green's functions from the reflection data at the surface. For this, no knowledge of the positions and properties of the reflecting interfaces is required. Once the full Green's functions are retrieved, reflection imaging can be carried out by which the primaries and multiples are

  17. XFEL OSCILLATOR SIMULATION INCLUDING ANGLE-DEPENDENT CRYSTAL REFLECTIVITY

    International Nuclear Information System (INIS)

    Fawley, William; Lindberg, Ryan; Kim, K.-J.; Shvyd'ko, Yuri

    2010-01-01

    The oscillator package within the GINGER FEL simulation code has now been extended to include angle-dependent reflectivity properties of Bragg crystals. Previously, the package was modified to include frequencydependent reflectivity in order to model x-ray FEL oscillators from start-up from shot noise through to saturation. We present a summary of the algorithms used for modeling the crystal reflectivity and radiation propagation outside the undulator, discussing various numerical issues relevant to the domain of high Fresnel number and efficient Hankel transforms. We give some sample XFEL-O simulation results obtained with the angle-dependent reflectivity model, with particular attention directed to the longitudinal and transverse coherence of the radiation output.

  18. A fiberoptic reflection oximeter.

    Science.gov (United States)

    Landsman, M L; Knop, N; Kwant, G; Mook, G A; Zijlstra, W G

    1978-03-20

    A catheter tip oximeter is described consisting of a cardiac catheter containing optical fibers, and incandescent light source, a light detection unit and a processing unit. Half of the optical fibers guide the light to the blood at the tip of the catheter, the other half the backscattered (reflected) light to the detection unit. The detection unit contains a dichroic mirror, transmitting most of the light with lambda less than 800 nm and reflecting most of the light with lambda greater than 900 nm, thus splitting the light into two beams. These pass through interference filters with nominal wavelengths of 640 and 920 nm respectively, and are focused on silicium barrier layer photocells. The photocell signals are amplified and fed into a divider giving the ratio of measuring (R640) and compensating (R920) photocell output. The relationship between log R640/R920 and oxygen saturation is represented by a slightly curved line. The relation may be linearized by subtracting a constant voltage from the divided output before taking the logarithm. The slope of the calibration line is dependent on the total haemoglobin concentration. Nonetheless an average calibration line can be used between 70 and 100% oxygen saturation. For 78 measurements of pig blood samples in this range (haemoglobin concentration between 96 and 161 g.1(-1)), the standard deviation of the difference between the fiberoptic oximeter and a Radiometer OSM1 oxygen saturation meter was 1.9% saturation, for 152 samples over the entire saturation range the standard deviation of the difference was 3.1% saturation. The influence of the flow velocity of blood on the light reflection depends on wavelength as well as on oxygen saturation. Therefore, complete compensation for the flow effect is not possible by simple means.

  19. The development of radiation protection

    International Nuclear Information System (INIS)

    Pochin, E.E.

    1981-01-01

    The harm that might be caused by radiation exposure was recognised within months of Rontgen's discovery of X-rays, and recommendations for protection of patients and workers with radiation were formulated first in 1928. In the light of increasing radiobiological, genetic and human epidemiological evidence, it became clear that there might be no threshold, below which harmful effects did not occur. Recommendation and practice in radiation protection reflected this opinion from the early 1950's, and emphasised the consequent need for minimising exposures, quantifying risks and revising the dose limits appropriate for internal radiation of body organs. (author)

  20. Reflections on preventive medicine.

    Science.gov (United States)

    Miettinen, Olli S

    2014-10-01

    Having thought much about medicine in my career-long effort to understand it and the research for its advancement, I have come to views rather different form the now-prevailing ones in respect to what preventive medicine is about; what epidemiology is in relation to preventive medicine; what distinguishes preventive medicine in preventive healthcare at large; the relation of preventive medicine to public health; the concept of health promotion; and also the core principles of preventive medicine. All of these views I set forth in this article, for the readers' critical reflection. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    1978-01-01

    The Cancergram deals with all aspects of radiation carcinogenesis. The term radiation here includes U-V radiation and the entire electromagnetic spectrum, electron and other charged particle beams, neutrons, and alpha and beta radiation from radioactive substances. Abstracts included concern relationships between radiation and carcinogenesis in humans, experimental induction of tumors in animals by irradiation, studies on the mechanism of radiation carcinogenesis at the cellular level, studies of RBE, dose response or dose threshold in relation to radiation carcinogenesis, and methods and policies for control of radiation exposure in the general population. In general, this Cancergram excludes abstracts on radio-therapy, radiologic diagnosis, radiation pathology, and radiation biology, where these articles have no bearing on radiation carcinogenesis

  2. Matter reflects Antimatter

    CERN Document Server

    Bianconi, A.; Cristiano, A.; Leali, M.; Lodi Rizzini, E.; Venturelli, L.; Zurlo, N.

    2008-01-01

    It is common belief that the interaction between antimatter and ordinary solid matter is dominated by annihilation. However, non-destructive processes may play a relevant role too. One century ago E. Rutherford wrote about the "diffuse reflection" of alpha and beta particles by thin layers of different metals: "The observations ... of Geiger and Marsden on the scattering of alpha rays indicate that some of the alpha particles must suffer a deflexion of more than a right angle at a single encounter.... It will be shown that the main deductions from the theory are independent of whether the central charge is supposed to be positive or negative". Although the theory of electromagnetic scattering is in first approximation independent of the relative sign of the colliding particles, in the case where projectile antiprotons are shot against a wall of solid matter the Rutherford diffuse reflection mechanism competes with the annihilation process. So it is not obvious at all that a relevant part of an antiproton beam...

  3. Reflection, Interrogatory, Provocation

    International Nuclear Information System (INIS)

    Carnes, W.E.

    2016-01-01

    This invited paper advances a framing context for considering next steps in HOF and organizational culture in light of the presentations and discussions that occur during the conference. Many of the contributions during the conference will represent results of scholarly research, structured investigations, or formal organizational improvement efforts. This contribution is intended as informal reflection by a 40-year nuclear veteran on themes from other presentations considering questions such as: ''Where do we think we are?, Are we better off as an industry based on what we have done?, Where do we think we need to go?, What do we think we need to do?, and, Why do we think these things?'' Our coming together on this occasion marks 30 years since the publication of INSAG-l. As we reflect on the past, perhaps it is time to pose a series of questions. Are we sustainers of a mature technology that is in some places declining and being replaced by other energy sources? If we consider nuclear a mature technology, should we focus most on operational excellence with renewed attention to managing the unexpected? Or, is innovation still a vital part of our industry?

  4. Synchrotron radiation

    International Nuclear Information System (INIS)

    Seddon, E.A.; Reid, R.J.

    1992-01-01

    Work at the Daresbury SRS has of necessity been interrupted this year (1991/92) due to the incorporation of Wiggler II. However, considerable beamtime was awarded before the shutdown and the major part of this appendix is concerned with the progress reports of the research undertaken then. The reports have been organised under the following broad headings: Molecular Science (19 papers), Surface and Materials Science (169 papers), Biological Science (85 papers), Instrumental and Technique Developments (13 papers) and Accelerator Physics (3 papers). It is hoped that in time the number of contributions on accelerator physics will grow to reflect the in-house activity on, for example, accelerator improvement and design. The research reports are preceded by the Annual Report of the Synchrotron Radiation Facilities Committee, which outlines the research highlights identified by that Committee (also included are details of the current membership of the SRFC and the chairmen of the Beamtime Allocation Panels). Following the reports are the specifications for the beamlines and stations. This year Section 3 contains 289 reports (nearly 100 more than last year) and the number of publications, generated by scientists and engineers who have used or are associated with Daresbury Laboratory facilities, has topped 500 for the first time. (author)

  5. GAMMA RAY REFLECTION FACTORS FROM CONCRETE

    Energy Technology Data Exchange (ETDEWEB)

    Chilton, Arthur B.

    1963-06-15

    By means of the differential dose albedo formula, the field from a point source of gamma radiation near a concrete-air interface is mapped for those conditions in which the distances involved are larger than a meanfree-path in concrete but substantially smaller than a mean-free-path in air. Once the parameters for the albedo formula are selected, the computation of reflection factors can be carried out to any desired degree of accuracy. Computational errors are kept to substantially less than 5% of the resulting output values. (C.E.S.)

  6. Reflection and Non-Reflection of Particle Wavepackets

    Science.gov (United States)

    Cox, Timothy; Lekner, John

    2008-01-01

    Exact closed-form solutions of the time-dependent Schrodinger equation are obtained, describing the propagation of wavepackets in the neighbourhood of a potential. Examples given include zero reflection, total reflection and partial reflection of the wavepacket, for the sech[superscript 2]x/a, 1/x[superscript 2] and delta(x) potentials,…

  7. Reflecting Contemporary Design Research

    DEFF Research Database (Denmark)

    Engholm, Ida

    2017-01-01

    In recent years, design research has been the object of growing attention in universities and academies throughout the world. The present paper addresses the heterogeneous character of design research and the current need for reflection on the various approaches and interests. For this purpose......, the paper follows two steps. First, it proposes a categorization of the field in the form of a position model. The paper’s underlying assumption is that design research as a discipline exists in many different forms that cannot necessarily be brought together under one common academic research tradition......; instead it is necessary to attempt to define the field in order to initiate discussions about what constitutes the various research bases for design. Second, the paper discusses the implication for future design research when it is an interdisciplinary field that involves many disciplines, mindsets...

  8. The Reflective Methodologists

    DEFF Research Database (Denmark)

    Kjær, Bjørg

    2013-01-01

    In recent years, a focus on inclusion and vulnerable children has reignited discussions about the quality of pedagogical work. It has also initiated processes of change that have challenged the Danish kindergarten tradition and the identity of the pedagogue in a number of different ways. In this ......In recent years, a focus on inclusion and vulnerable children has reignited discussions about the quality of pedagogical work. It has also initiated processes of change that have challenged the Danish kindergarten tradition and the identity of the pedagogue in a number of different ways...... in which the practical sense and tacit knowledge are related to questions of power and social actors’ strategies for positioning themselves within a social space. This demands a particular focus on the historical effect of the concept of ‘the reflective practitioner’ as a symbolic marker of identity...

  9. Reflections on SLAP

    International Nuclear Information System (INIS)

    Cooke, Roger

    1997-01-01

    The SLAP data bases represent a major step forward in the reliability analysis of passive components. The present reflections are motivated by draft documentation for SLAP and have profited greatly from discussions with the SLAP team. We collect a number of remarks and suggestions: The use of event and failure fields to organize the data seems sensible and feasible, from a data analysis viewpoint. Influence factors, i. e. environmental influences which are affected by plant operations, are clearly important yet very difficult to accommodate in any straightforward data analysis methodology. We would welcome a serious effort to estimate the exposure in the various exposure cells. These estimates would not be based on failure records, but on knowledge of plant design and operations. Quantitative expert judgement might be a viable alternative to a massive review of all plants in the SLAP data base

  10. Reflections on Conformal Spectra

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    We use modular invariance and crossing symmetry of conformal field theory to reveal approximate reflection symmetries in the spectral decompositions of the partition function in two dimensions in the limit of large central charge and of the four-point function in any dimension in the limit of large scaling dimensions Δ0 of external operators. We use these symmetries to motivate universal upper bounds on the spectrum and the operator product expansion coefficients, which we then derive by independent techniques. Some of the bounds for four-point functions are valid for finite Δ0 as well as for large Δ0. We discuss a similar symmetry in a large spacetime dimension limit. Finally, we comment on the analogue of the Cardy formula and sparse light spectrum condition for the four-point function. (based on 1510.08772 with Kim & Ooguri). This seminar will be given via videolink

  11. Reflections on academic video

    Directory of Open Access Journals (Sweden)

    Thommy Eriksson

    2012-11-01

    Full Text Available As academics we study, research and teach audiovisual media, yet rarely disseminate and mediate through it. Today, developments in production technologies have enabled academic researchers to create videos and mediate audiovisually. In academia it is taken for granted that everyone can write a text. Is it now time to assume that everyone can make a video essay? Using the online journal of academic videos Audiovisual Thinking and the videos published in it as a case study, this article seeks to reflect on the emergence and legacy of academic audiovisual dissemination. Anchoring academic video and audiovisual dissemination of knowledge in two critical traditions, documentary theory and semiotics, we will argue that academic video is in fact already present in a variety of academic disciplines, and that academic audiovisual essays are bringing trends and developments that have long been part of academic discourse to their logical conclusion.

  12. Reflections on Student Persistence

    Directory of Open Access Journals (Sweden)

    Vincent Tinto

    2017-07-01

    Full Text Available The Feature for this issue Reflections on Student Persistence has been prepared by Professor Vincent Tinto, Distinguished University Professor Emeritus at Syracuse University, United States of America (USA and a longtime friend and supporter of STARS. Vincent explores the case for motivation to be considered as a significant aspect of the tertiary student psyche by drawing on theoretical frameworks, research and practical experiences related to the issue. He synthesises this extensive, detailed, rich but often somewhat impenetrable data into a trilogy of clear and credible key dimensions of the motivation construct student self efficacy, sense of belonging and perceived value of the curriculum. This interpretation of the literature is a personal but informed reflection and is a timely piece which highlights the breadth and profundity of the presentations at this year's conference in Adelaide, Australia where students in all their diversity are central to our focus on enhancing the student experience. In this opening article, Vincent refers directly to the STARS papers selected for this Conference issue of the Journal which also address the importance of student persistence, self-efficacy and building the sense of belonging within their own institutional communities (Fernandes, Ford, Rayner & Pretorius; Kahu, Nelson, & Picton; McFarlane, Spes-Skrbis & Taib; Naylor; Smallhorn. Echoing his position on social justice and his advocacy for underserved students, Vincent reminds us that educational equity gaps still exist, and he encourages us to see the issue of persistence through the eyes of the students to support their perseverance and completion and thereby help reduce educational disadvantage.

  13. Reflective Practices for Teacher Education

    Directory of Open Access Journals (Sweden)

    Paulus Kuswandono

    2017-01-01

    Full Text Available Studies on reflective practice in teacher education are increasingly getting more attention at least in the last 2 decades. This article discusses concepts of reflection and how it is implemented in educating pre-service teachers on their early stage of professional learning. The purposes of doing the reflection for pre-service teachers are not only for illuminating their professional learning experiences, but also to critically reflect their vocation as teachers, including the values which may be dictated to them through rigid regulations. Reflection in teacher education is crucial as it connects well with learning in that learners use reflection to exercise their mind and to evaluate their learning experiences. Besides, this article also highlights some perceived difficulties to implement reflective practice, as well as ways how to promote reflection.   DOI: https://doi.org/10.24071/llt.2012.150102

  14. GHOSTLY REFLECTIONS IN THE PLEIADES

    Science.gov (United States)

    2002-01-01

    NASA's Hubble Space Telescope has caught the eerie, wispy tendrils of a dark interstellar cloud being destroyed by the passage of one of the brightest stars in the Pleiades star cluster. Like a flashlight beam shining off the wall of a cave, the star is reflecting light off the surface of pitch black clouds of cold gas laced with dust. These are called reflection nebulae. The famous cluster is easily visible in the evening sky during the winter months as a small grouping of bright blue stars, named after the 'Seven Sisters' of Greek mythology. Resembling a small dipper, this star cluster lies in the constellation Taurus at a distance of about 380 light-years from Earth. The unaided eye can discern about half a dozen bright stars in the cluster, but a small telescope will reveal that the Pleiades contains many hundreds of fainter stars. In many cases, the nebulae surrounding star clusters represent material from which the stars have formed recently. However the Pleiades nebulosity is actually an independent cloud, drifting through the cluster at a relative speed of about 6.8 miles/second (11 kilometers/second). In 1890, American astronomer E. E. Barnard, observing visually with the Lick Observatory 36-inch telescope in California, discovered an exceptionally bright nebulosity adjacent to the bright Pleiades star Merope. It is now cataloged as IC 349, or 'Barnard's Merope Nebula.' IC 349 is so bright because it lies extremely close to Merope--only about 3,500 times the separation of the Earth from the Sun, or about 0.06 light-year--and thus is strongly illuminated by the star's light. In the new Hubble image, Merope itself is just outside the frame on the upper right. The colorful rays of light at the upper right, pointing back to the star, are an optical phenomenon produced within the telescope, and are not real. However, the remarkable parallel wisps extending from lower left to upper right are real features, revealed for the first time through Hubble's high

  15. Guided and Unguided Student Reflections

    OpenAIRE

    Matheson, Amanda; Wood, Laura; Franklin, Scott V.

    2017-01-01

    Self-reflection is important metacognitive skill, enabling students to build coherence into their learning and embed content in a broader context. While various pedagogical techniques exist to encourage student reflection, little research has examined the differences between formally guided, partially guided and unguided reflections. This study focuses on student responses to online Guided Reflection Forms (GRFs) from students in a first-semester non-physics class and, separately, a sophomore...

  16. Students’ Learning through Reflective Journaling

    OpenAIRE

    Alvyda Liuolienė; Regina Metiūnienė

    2011-01-01

    The aim of the article is to get acquainted with the types of journals used in education to help students to learn. The paper presents some ways of fostering student’s learning through reflective journaling. It also describes the key aspects of a new method ARRIVE cycle in connection with teachers preparation to use reflective journals in a classroom. The article also presents self-assessment in reflective journaling and students’ need to self-evaluate their learning process. Reflective journ...

  17. Radiation practices and radiation measurements

    International Nuclear Information System (INIS)

    2008-03-01

    The guide presents the principal requirements on accuracy of radiation measurements and on the approval, calibration and operating condition inspections of radiation meters, together with requirements for dosimetric services measuring the individual radiation doses of workers engaged in radiation work (approved dosimetric services). The Guide also sets out the definitions of quantities and units used in radiation measurements. The radiation protection quantities used for assessing the harmful effects of radiation and for expressing the maximum values for radiation exposure (equivalent dose and effective dose) are set out in Guide ST 7.2. This Guide concerns measurements of ionizing radiation involved in radiation practices, the results of which are used for determining the radiation exposure of workers engaged in radiation work and members of the public, and of patients subject to the use of radiation in health services, or upon the basis of which compliance with safety requirements of appliances currently in use and of their premises of use or of the workplaces of workers is ensured. The Guide also concerns measurements of the radon concentration of inhaled air in both workplaces and dwellings. The Guide does not apply to determining the radiation exposure of aircrews, determination of exposure caused by internal radiation, or measurements made to protect the public in the event of, or in preparation for abnormal radiation conditions

  18. Reflection in Russian Educational Psychology.

    Science.gov (United States)

    Nelissen, Jo M. C.; Tomic, Welko

    This paper discusses the cultural-historical school founded by Vygotsky, Luria, and Leontiev as the theoretical background of Russian educational psychologists who have been studying how children learn to reflect. Two approaches to reflection are examined within the cultural-historical tradition: first, reflection--like other higher psychological…

  19. Reflective Practice: Origins and Interpretations

    Science.gov (United States)

    Reynolds, Michael

    2011-01-01

    The idea of reflection is central to the theory and practice of learning--especially learning which is grounded in past or current experience. This paper proposes a working definition of reflection and reviews its origins and recent developments. The author also provides an account of "critical reflection", including its rationale and…

  20. Characterizing the solar reflection from wildfire smoke plumes using airborne multiangle measurements

    Science.gov (United States)

    Gatebe, C. K.; Varnai, T.; Gautam, R.; Poudyal, R.; Singh, M. K.

    2016-12-01

    To help better understand forest fire smoke plumes, this study examines sunlight reflected from plumes that were observed over Canada during the ARCTAS campaign in summer 2008. In particular, the study analyzes multiangle and multispectral measurements of smoke scattering by the airborne Cloud Absorption Radiometer (CAR). In combination with other in-situ and remote sensing information and radiation modeling, CAR data is used for characterizing the radiative properties and radiative impact of smoke particles—which inherently depend on smoke particle properties that influence air quality. In addition to estimating the amount of reflected and absorbed sunlight, the work includes using CAR data to create spectral and broadband top-of-atmosphere angular distribution models (ADMs) of solar radiation reflected by smoke plumes, and examining the sensitivity of such angular models to scene parameters. Overall, the results help better understand the radiative properties and radiative effects of smoke particles, and are anticipated to help better interpret satellite data on smoke plumes.

  1. Infrared Radiation and Blackbody Radiation

    OpenAIRE

    2005-01-01

    tut present graph Tutorial Presentation Graph Interactive Media Element This interactive tutorial covers the following: How infrared radiation was discovered., The regions of infrared radiation and their relations to temperature., The nature of blackbody radiation and Planck's radiation law., The relationship between temperature and the power emitted by radiation.The interactions in this tutorial include clicking to reveal new information, and questions that help students...

  2. In situ observation of surface reactions with synchrotron radiation induced semiconductor processes by infrared reflection absorption spectroscopy using buried metal layer substrates; Umekomi kinzokuso kiban wo mochiita sekigai hansha kyushu supekutoruho ni yoru hoshako reiki handotai process hanno no sonoba kansatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yoshigoe, A.; Hirano, S. [The Graduate University for Advanced Studies, Yokohama (Japan); Mase, K.; Urisu, T. [Institute for Molecular Science, Aichi (Japan)

    1996-11-20

    It is known that infrared reflection absorption spectroscopy (IRAS) on semiconductor or insulator surfaces becomes practicable by using buried metal layer (BML) substrates, in which the metal thin film is buried order semiconductor or insulator films. In this work, IRAS has been measured for Langmuir-Blodgett films deposited on the BML substrate with SiO2/Al/Si(100) structure and the observed spectrum intensity has been quantitatively compared with the calculation assuming the ideal multilayer structure for the BML substrate. The BML-IRAS using CoSi2 has been adopted to the detection of SiHn on the Si (100) substrate during synchrotron radiation (SR) stimulated Si2H6 gas source molecular beam epitaxy. It has been found that SiH2 and SiH3 on the Si (100) surface are easily decomposed by SR, but SiH can`t be decomposed. From these experiments, it has been concluded that the BML-IRAS is an useful in situ observation technique for the photo-stimulated surface reactions. 26 refs., 9 figs.

  3. European Radiation Protection Course - Basics

    International Nuclear Information System (INIS)

    Massiot, Philippe; Ammerich, Marc; Viguier, Herve; Jimonet, Christine; Bruchet, Hugues; Vivier, Alain; Bodineau, Jean-Christophe; Etard, Cecile; Metivier, Henri; Moreau, Jean-Claude; Nourredine, Abdel-Mijd

    2014-01-01

    Radiation protection is a major challenge in the industrial applications of ionising radiation, both nuclear and non-nuclear, as well as in other areas such as the medical and research domains. The overall objective of this textbook is to participate to the development of European high-quality scheme and good practices for education and training in radiation protection (RP), coming from the new Council Directive 2013/59/Euratom laying down basic safety standards for protection against the dangers arising from exposure to ionising radiation. These ERPTS (European Radiation Protection Training Scheme) reflects the needs of the Radiation Protection Expert (RPE) and the Radiation Protection Officer (RPO), specifically with respect to the Directive 2013/59/Euratom in all sectors where ionising radiation are applied. To reflect the RPE training scheme, six chapters have been developed in this textbook: Radioactivity and nuclear physics; Interaction of ionising radiation with matter; Dosimetry; Biological effects of ionising radiation; Detection and measurement of ionising radiation; Uses of sources of ionising radiation. The result is a homogeneous textbook, dealing with the ERPTS learning outcomes suggested by ENETRAPII project (European Network on Education and Training in Radiological Protection II) from the 7. Framework Programme. A cyber-book is also part of the whole training material to develop the concept of 'learning more' (http://www.rpe-training.eu). The production of this first module 'basics' training material, in the combined form of a textbook plus a cyber-book as learning tools, will contribute to facilitate mutual recognition and enhanced mobility of these professionals across the European Union. (authors)

  4. Teachers’ way of reflecting

    DEFF Research Database (Denmark)

    Lund, Lea

    2016-01-01

    This paper contributes to insights on teachers’ thinking and practice by building partly on the large amount of prior research in the field of continuing professional development (in line with ISATT), and partly on examples from an empirical small-scale study executed in Denmark. The purpose of t......’ reflections on practice. Based on this model, the paper provides a proposal regarding how to work with teachers’ professional development and learning processes. Educational implications and future research directions are discussed.......This paper contributes to insights on teachers’ thinking and practice by building partly on the large amount of prior research in the field of continuing professional development (in line with ISATT), and partly on examples from an empirical small-scale study executed in Denmark. The purpose...... of the Danish study was to investigate and understand teachers’ classroom experiences using Fenstermacher’s approach to develop a practical argument, as these classroom experiences are regarded as a potential source of learning for teachers. A three-level scale model from the study describes the teach-ers...

  5. Radiation safety

    International Nuclear Information System (INIS)

    Jain, Priyanka

    2014-01-01

    The use of radiation sources is a privilege; in order to retain the privilege, all persons who use sources of radiation must follow policies and procedures for their safe and legal use. The purpose of this poster is to describe the policies and procedures of the Radiation Protection Program. Specific conditions of radiation safety require the establishment of peer committees to evaluate proposals for the use of radionuclides, the appointment of a radiation safety officer, and the implementation of a radiation safety program. In addition, the University and Medical Centre administrations have determined that the use of radiation producing machines and non-ionizing radiation sources shall be included in the radiation safety program. These Radiation Safety policies are intended to ensure that such use is in accordance with applicable State and Federal regulations and accepted standards as directed towards the protection of health and the minimization of hazard to life or property. It is the policy that all activities involving ionizing radiation or radiation emitting devices be conducted so as to keep hazards from radiation to a minimum. Persons involved in these activities are expected to comply fully with the Canadian Nuclear Safety Act and all it. The risk of prosecution by the Department of Health and Community Services exists if compliance with all applicable legislation is not fulfilled. (author)

  6. STUDY OF REFLECTION COEFFICIENT DISTRIBUTION FOR ANTI-REFLECTION COATINGS ON SMALL-RADIUS OPTICAL PARTS

    Directory of Open Access Journals (Sweden)

    L. A. Gubanova

    2015-03-01

    Full Text Available The paper deals with findings for the energy reflection coefficient distribution of anti- reflection coating along the surface of optical elements with a very small radius (2-12 mm. The factors influencing the magnitude of the surface area of the optical element, in which the energy reflection coefficient is constant, were detected. The main principles for theoretical models that describe the spectral characteristics of the multilayer interference coatings were used to achieve these objectives. The relative size of the enlightenment area is defined as the ratio of the radius for the optical element surface, where the reflection is less than a certain value, to its radius (ρ/r. The result of research is the following: this size is constant for a different value of the curvature radius for the optical element made of the same material. Its value is determined by the refractive index of material (nm, from which the optical element was made, and the design of antireflection coatings. For single-layer coatings this value is ρ/r = 0.5 when nm = 1.51; and ρ/r = 0.73 when nm = 1.75; for two-layer coatings ρ/r = 0.35 when nm = 1.51 and ρ/r = 0.41 when nm = 1.75. It is shown that with increasing of the material refractive index for the substrate size, the area of minimum reflection coefficient is increased. The paper considers a single-layer, two-layer, three-layer and five-layer structures of antireflection coatings. The findings give the possibility to conclude that equal thickness coverings formed on the optical element surface with a small radius make no equal reflection from the entire surface, and distribution of the layer thickness needs to be looked for, providing a uniform radiation reflection at all points of the spherical surface.

  7. Adaptive infrared-reflecting systems inspired by cephalopods

    Science.gov (United States)

    Xu, Chengyi; Stiubianu, George T.; Gorodetsky, Alon A.

    2018-03-01

    Materials and systems that statically reflect radiation in the infrared region of the electromagnetic spectrum underpin the performance of many entrenched technologies, including building insulation, energy-conserving windows, spacecraft components, electronics shielding, container packaging, protective clothing, and camouflage platforms. The development of their adaptive variants, in which the infrared-reflecting properties dynamically change in response to external stimuli, has emerged as an important unmet scientific challenge. By drawing inspiration from cephalopod skin, we developed adaptive infrared-reflecting platforms that feature a simple actuation mechanism, low working temperature, tunable spectral range, weak angular dependence, fast response, stability to repeated cycling, amenability to patterning and multiplexing, autonomous operation, robust mechanical properties, and straightforward manufacturability. Our findings may open opportunities for infrared camouflage and other technologies that regulate infrared radiation.

  8. Radiation safety

    International Nuclear Information System (INIS)

    Woods, D.A.

    1982-01-01

    Sections include: dose units, dose limits, dose rate, potential hazards of ionizing radiations, control of internal and external radiation exposure, personal dosemeters, monitoring programs and transport of radioactive material (packaging and shielding)

  9. Synchrotron radiation

    International Nuclear Information System (INIS)

    Hallmeier, K.H.; Meisel, A.; Ranft, J.

    1982-01-01

    The physical background and the properties of synchrotron radiation are described. The radiation offers many useful applications in the fields of spectroscopy and structural investigations. Some examples are given

  10. Radiation monitoring

    International Nuclear Information System (INIS)

    Larsson, L.Eh.; B'yuli, D.K.; Karmikel, Dzh.Kh.E.

    1985-01-01

    Recommendations on radiation monitoring of personnel, used medical ionizing radiation source, are given. The necessity to carry out radiation monitoring of situation at medical personnel's positions and personnel dosimetry is marked. It is convenient to subdivide radiation monitoring into 3 types: usual, surgical and special. Usual monitoring is connected with current work; surgical monitoring is carried out to receive information during a concrete operation; special monitoring is used to detect possible deviation from standard conditions of work or when suspecting them

  11. Medical radiation

    International Nuclear Information System (INIS)

    1992-01-01

    This leaflet in the At-a-Glance Series describes the medical use of X-rays, how X-rays help in diagnosis, radiation protection of the patient, staff protection, how radioactive materials in nuclear medicine examinations help in diagnosis and the use of radiation in radiotherapy. Magnetic resonance imaging, a diagnostic technique involving no ionizing radiation, is also briefly examined. The role of the NRPB in the medical use of radiation is outlined. (UK)

  12. Ionizing radiation

    International Nuclear Information System (INIS)

    Dennis, J.A.

    1982-01-01

    The subject is discussed under the headings: characteristics of ionizing radiations; biological effects; comparison of radiation and other industrial risks; principles of protection; cost-benefit analysis; dose limits; the control and monitoring of radiation; reference levels; emergency reference levels. (U.K.)

  13. Radiation watchdog

    International Nuclear Information System (INIS)

    Manning, R.

    1984-01-01

    Designated by WHO as a Collaborating Centre, the Radiation Emergency Assistance Center/Training Site (REAC/TS) in Oak Ridge, Tennessee provides assistance to all countries of the Americas in radiation accidents including human contamination or overexposure. It also conducts courses in radiation emergency response for health professionals from throughout the world

  14. Radiation hazards

    International Nuclear Information System (INIS)

    Rausch, L.

    1979-01-01

    On a scientific basis and with the aid of realistic examples, the author gives a popular introduction to an understanding and judgment of the public discussion over radiation hazards: Uses and hazards of X-ray examinations, biological radiation effects, civilisation risks in comparison, origins and explanation of radiation protection regulations. (orig.) [de

  15. Effect of reflective practice education on self-reflection, insight, and reflective thinking among experienced nurses: a pilot study.

    Science.gov (United States)

    Asselin, Marilyn E; Fain, James A

    2013-01-01

    A mixed-method study was conducted to determine whether nurses' participation in a reflective practice continuing education program using a structured reflection model makes a difference in nurses' self-reflection, insight, and reflective thinking about clinical practice situations. Findings suggested that use of structured reflection using question cues, written narratives, and peer-facilitated reflection increased nurses' engagement in self-reflection and enhanced reflective thinking in practice. Including reflective practice education in novice orientation and preceptor training may be beneficial.

  16. Are low radiation doses Dangerous?

    International Nuclear Information System (INIS)

    Garcia Lima, O.; Cornejo, N.

    1996-01-01

    In the last few years the answers to this questions has been affirmative as well as negative from a radiation protection point of view low doses of ionizing radiation potentially constitute an agent causing stochasting effects. A lineal relation without threshold is assumed between dose and probability of occurrence of these effects . Arguments against the danger of probability of occurrence of these effects. Arguments again the danger of low dose radiation are reflected in concepts such as Hormesis and adaptive response, which are phenomena that being studied at present

  17. Berlin Reflectance Spectral Library (BRSL)

    Science.gov (United States)

    Henckel, D.; Arnold, G.; Kappel, D.; Moroz, L. V.; Markus, K.

    2017-09-01

    The Berlin Reflectance Spectral Library (BRSL) provides a collection of reflectance spectra between 0.3 and 17 µm. It was originally dedicated to support space missions to small solar system bodies. Meanwhile the library includes selections of biconical reflectance spectra for spectral data analysis of other planetary bodies as well. The library provides reference spectra of well-characterized terrestrial analogue materials and meteorites for interpretation of remote sensing reflectance spectra of planetary surfaces. We introduce the BRSL, summarize the data available, and access to use them for further relevant applications.

  18. Students’ Learning through Reflective Journaling

    Directory of Open Access Journals (Sweden)

    Alvyda Liuolienė

    2011-04-01

    Full Text Available The aim of the article is to get acquainted with the types of journals used in education to help students to learn. The paper presents some ways of fostering student’s learning through reflective journaling. It also describes the key aspects of a new method ARRIVE cycle in connection with teachers preparation to use reflective journals in a classroom. The article also presents self-assessment in reflective journaling and students’ need to self-evaluate their learning process. Reflective journaling as central to students’ self-evaluation is described as a means of fostering metacognition.

  19. Ionizing radiations

    International Nuclear Information System (INIS)

    Newton, W.

    1984-01-01

    The purpose of this article is to simplify some of the relevant points of legislation, biological effects and protection for the benefit of the occupational health nurse not familiar with the nuclear industries. The subject is dealt with under the following headings; Understanding atoms. What is meant by ionizing radiation. Types of ionizing radiation. Effects of radiation: long and short term somatic effects, genetic effects. Control of radiation: occupational exposure, women of reproductive age, medical aspects, principles of control. The occupational health nurse's role. Emergency arrangements: national arrangements for incidents involving radiation, action to be taken by the nurse. Decontamination procedures: external and internal contamination. (U.K.)

  20. Studies of the Reflection, Refraction and Internal Reflection of Light

    Science.gov (United States)

    Lanchester, P. C.

    2014-01-01

    An inexpensive apparatus and associated experiments are described for studying the basic laws of reflection and refraction of light at an air-glass interface, and multiple internal reflections within a glass block. In order to motivate students and encourage their active participation, a novel technique is described for determining the refractive…

  1. Cultivating Reflective Practitioners in Technology Preparation: Constructing TPACK through Reflection

    Directory of Open Access Journals (Sweden)

    Liangyue Lu

    2013-12-01

    Full Text Available Teaching is a complex profession, which is further complicated by the integration of technology into classrooms. Reflection can help teachers unpack the complexity in their practice. Reflection can be an effective instructional strategy in helping preservice teachers develop technological pedagogical content knowledge (TPACK, the complex and dynamic knowledge necessary for effective technology integration into instruction. In this study, reflective activities were integrated into a Learning By Design (LBD environment, which was created to help preservice teachers develop TPACK. This paper investigated the participants’ TPACK development and examined how reflection helped them construct TPACK. Through content analysis of the participants’ reflective journals, the researcher found that the preservice teachers developed initial TPACK awareness. However, their reflection in technology knowledge and the content aspects of TPACK were limited and superficial. Interviews with the participants showed reflection helped the preservice teachers remember what they learned by describing and elaborating on their in-class experiences, pushed them to think about how to apply what they learned in their future classrooms, and helped them become more reflective and open-minded about using technology in classrooms. Finally, the researcher discussed this study’s implications for teacher educators and researchers.

  2. Reflection and Reflective Practice Discourses in Coaching: A Critical Analysis

    Science.gov (United States)

    Cushion, Christopher J.

    2018-01-01

    Reflection and reflective practice is seen as an established part of coaching and coach education practice. It has become a "taken-for-granted" part of coaching that is accepted enthusiastically and unquestioningly, and is assumed to be "good" for coaching and coaches. Drawing on sociological concepts, a primarily Foucauldian…

  3. Postgraduate Education to Support Organisation Change: A Reflection on Reflection

    Science.gov (United States)

    Stewart, Jim; Keegan, Anne; Stevens, Pam

    2008-01-01

    Purpose: This paper aims to explore how teaching and assessing reflective learning skills can support postgraduate practitioners studying organisational change and explores the challenges for tutors in assessing these journals. Design/methodology/approach: Assessment criteria were developed from the literature on reflective practice and…

  4. Changes in the reflectance of ex situ leaves: A methodological approach

    Science.gov (United States)

    Ponzoni, Flavio Jorge; Inoe, Mario Takao

    1992-04-01

    The main aspects of the interaction between electromagnetic radiation and detached leaves are presented. An experiment with Eucalipto and Araucaria detached leaves is described, including the description of the methodologies utilized in the collection and storage of the reflectance.

  5. Highly Reflecting, Broadband Deformable Membrane Mirror for Wavefront Control Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I STTR project will develop a highly reflecting, broadband, radiation resistant, low-stress and lightweight, membrane integrated into an electrostatically...

  6. Analysis of the temporal variation of radiation balance components in arid rice (Oryza sativa L.) culture

    International Nuclear Information System (INIS)

    Prates, J.E.; Coelho, D.T.; Steinmetz, S.

    1988-01-01

    The time variation of measured radiation balance components in a cultived rice area (Oryza sativa L.) under arid conditions in the Brazil central-west region was analysed. The relation between global solar radiation, radiation balance, reflected radiation and terrestrial effective radiation in three different stages of the culture development: vegetative stage; blooming and maturation, was determined. (M.C.K.) [pt

  7. Ubuntu feminism: Tentative reflections

    Directory of Open Access Journals (Sweden)

    Drucilla Cornell

    2015-06-01

    Full Text Available The starting-point for the article is to provide a brief background on the Ubuntu Project that Prof. Drucilla Cornell convened in 2003; most notably the interviews conducted in Khayamandi, the support of a sewing collective, and the continued search to launch an Ubuntu Women�s Centre. The article will reflect on some of the philosophical underpinnings of ubuntu, whereafter debates in Western feminism will be revisited. Ubuntu feminism is suggested as a possible response to these types of feminisms. The authors support an understanding of ubuntu as critique and ubuntu feminism accordingly as a critical intervention that recalls a politics of refusal. The article ends by raising the importance of thinking about spatiality through ubuntu, and vice versa. It may seem strange to title an article Ubuntu feminism when feminism itself has often been identified as a European or Western idea. But, this article will argue that ubuntu offers conceptions of transindividuality and ways of social belonging that could respond in a meaningful way to some of European feminism�s own dilemmas and contradictions. Famously, one of the most intense debates in feminism was between those who defended an ethic of care in a relational view of the self, on one side, and those feminists who held on to more traditional conceptions of justice, placing an emphasis on individuality and autonomy, on the other side. The authors will suggest that ubuntu could address this tension in feminism. Thus, in this article the focus will not simply be on ubuntu, in order to recognise that there are other intellectual heritages worthy of consideration, other than those in Europe and the United States. It will also take a next step in arguing that ubuntu may be a better standpoint entirely from which to continue thinking about what it means to be a human being, as well as how to conceive of the integral interconnection human beings all have with one another. This connection through

  8. Radiation protection

    International Nuclear Information System (INIS)

    Jain, Aman; Sharma, Shivam; Parasher, Abhishek

    2014-01-01

    Radiation dose measurement, field of radiobiology, is considered to be critical factor for optimizing radiation protection to the health care practitioners, patients and the public. This lead to equipment that has dose - area product meters permanently installed. In many countries and even institution, the range of equipment is vast and with the opportunity for radiation protection and dose recording varies considerably. Practitioners must move with the changed demands of radiation protection but in many cases without assistance of modern advancements in technology Keeping the three basic safety measures Time, Dose and Shielding we can say 'Optimum dose is safe dose' instead of 'No dose is safe dose'. The purpose enclosed within the title 'Radiation Protection'. The use of radiation is expanding widely everyday around the world and crossing boundaries of medical imaging, diagnostic and. The way to get the ''As low as reasonably achievable' is only achievable by using methodology of radiation protection and to bring the concern of general public and practitioners over the hazards of un-necessary radiation dose. Three basic principles of radiation protection are time, distance and shielding. By minimizing the exposure time increasing the distance and including the shielding we can reduce the optimum range of dose. The ability of shielding material to attenuate radiation is generally given as half value layer. This is the thickness of the material which will reduce the amount of radiation by 50%. Lab coat and gloves must be worn when handling radioactive material or when working in a labeled radiation work area. Safety glasses or other appropriate splash shields should be used when handling radioactive material. 1. Reached to low dose level to occupational workers, public as per prescribed dose limit. 2. By mean of ALARA principle we achieved the protection from radiation besides us using the radiation for our benefit

  9. Radiation balance in the sweet sorghum crop

    International Nuclear Information System (INIS)

    Assis, F.N. de; Mendez, M.E.G.; Martins, S.R.; Verona, L.A.

    1987-01-01

    The fluxes of incident solar radiation, reflected and net radiation were measured during the growing cicle of two fields of sweet sorghum (Sorghum bicolor L.), cus. BR-501 and BR-503, maintained under convenient irrigation level. Resultant data allowed to estimate the crop albedo as well as the estimates of Rn. (M.A.C.) [pt

  10. Reflectometry with synchrotron radiation; Reflektometrie mit Synchrotronstrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Krumrey, Michael [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany). Arbeitsgruppe ' Roentgenradiometrie' ; Cibik, Levent; Fischer, Andreas; Gottwald, Alexander; Kroth, Udo; Scholze, Frank

    2014-09-15

    The measurement of the reflectivity for VUV, XUV, and X-radiation at the PTB synchrotron radiation sources is described. The corresponding data of the used beams are presented. Results of experiments on a Cu-Ni double-layer, SiO{sub 2}, Si, and MgF{sub 2} are presented. (HSI)

  11. Numerical simulations of a coupled radiative?conductive heat transfer model using a modified Monte Carlo method

    KAUST Repository

    Kovtanyuk, Andrey E.; Botkin, Nikolai D.; Hoffmann, Karl-Heinz

    2012-01-01

    Radiative-conductive heat transfer in a medium bounded by two reflecting and radiating plane surfaces is considered. This process is described by a nonlinear system of two differential equations: an equation of the radiative heat transfer

  12. Occupational radiation protection. Safety guide

    International Nuclear Information System (INIS)

    2002-01-01

    Guides together reflect the current internationally accepted principles and recommended practices in occupational radiation protection, with account taken of the major changes that have occurred over the past decade. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The present Safety Guide provides general guidance on the establishment of an effective radiation protection programme for occupational exposure, in accordance with the requirements of the Basic Safety Standards and appropriate for the sources of radiation likely to be encountered in the workplaces in question

  13. Occupational radiation protection. Safety guide

    International Nuclear Information System (INIS)

    2006-01-01

    Guides together reflect the current internationally accepted principles and recommended practices in occupational radiation protection, with account taken of the major changes that have occurred over the past decade. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The present Safety Guide provides general guidance on the establishment of an effective radiation protection programme for occupational exposure, in accordance with the requirements of the Basic Safety Standards and appropriate for the sources of radiation likely to be encountered in the workplaces in question

  14. Occupational radiation protection. Safety guide

    International Nuclear Information System (INIS)

    1999-01-01

    Guides together reflect the current internationally accepted principles and recommended practices in occupational radiation protection, with account taken of the major changes that have occurred over the past decade. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The present Safety Guide provides general guidance on the establishment of an effective radiation protection programme for occupational exposure, in accordance with the requirements of the Basic Safety Standards and appropriate for the sources of radiation likely to be encountered in the workplaces in question

  15. Occupational radiation protection. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    Guides together reflect the current internationally accepted principles and recommended practices in occupational radiation protection, with account taken of the major changes that have occurred over the past decade. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The present Safety Guide provides general guidance on the establishment of an effective radiation protection programme for occupational exposure, in accordance with the requirements of the Basic Safety Standards and appropriate for the sources of radiation likely to be encountered in the workplaces in question

  16. Terahertz wave reflective sensing and imaging

    Science.gov (United States)

    Zhong, Hua

    Sensing and imaging technologies using terahertz (THz) radiation have found diverse applications as they approach maturity. Since the burgeoning of this technique in the 1990's, many THz sensing and imaging investigations have been designed and conducted in transmission geometry, which provides sufficient phase and amplitude contrast for the study of the spectral properties of targets in the THz domain. Driven by rising expectations that THz technology will be a potential candidate in the next generation of security screening, remote sensing, biomedical imaging and non-destructive testing (NDT), most THz sensing and imaging modalities are being extended to reflection geometry, which offers unique and adaptive solutions, and multi-dimensional information in many real scenarios. This thesis takes an application-focused approach to the advancement of THz wave reflective sensing and imaging systems: The absorption signature of the explosive material hexahydro-1,3,5-trinitro-1,3,5triazine (RDX) is measured at 30 m---the longest standoff distance so far attained by THz time-domain spectroscopy (THz-TDS). The standoff distance sensing ability of THz-TDS is investigated along with discussions specifying the influences of a variety of factors such as propagation distance, water vapor absorption and collection efficiency. Highly directional THz radiation from four-wave mixing in laser-induced air plasmas is first observed and measured, which provides a potential solution for the atmospheric absorption effect in standoff THz sensing. The simulations of the beam profiles also illuminate the underlying physics behind the interaction of the optical beam with the plasma. THz wave reflective spectroscopic focal-plane imaging is realized the first time. Absorption features of some explosives and related compounds (ERCs) and biochemical materials are identified by using adaptive feature extraction method. Good classification results using multiple pattern recognition methods are

  17. Atoms, Radiation, and Radiation Protection

    CERN Document Server

    Turner, James E

    2007-01-01

    Atoms, Radiation, and Radiation Protection offers professionals and advanced students a comprehensive coverage of the major concepts that underlie the origins and transport of ionizing radiation in matter. Understanding atomic structure and the physical mechanisms of radiation interactions is the foundation on which much of the current practice of radiological health protection is based. The work covers the detection and measurement of radiation and the statistical interpretation of the data. The procedures that are used to protect man and the environment from the potential harmful effects of

  18. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with the design and measurement of physical parameters used in theory or to support biological experiments. The radiation biophysics program tests and uses the theoretical developments for experimental design, and provides information for further theoretical development through experiments on cellular systems

  19. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with design and measurement of those physical parameters used in the theory or to support biological experiments. The radiation biophysics program tests and makes use of the theoretical developments for experimental design. Also, this program provides information for further theoretical development through experiments on cellular systems

  20. Ethical Reflections on Becoming Teachers

    Science.gov (United States)

    Joseph, Pamela Bolotin

    2016-01-01

    This study analyzes narratives written in a culminating graduate seminar on reflective practice by 36 new secondary teachers who were asked to consider their moral beliefs, moral values and system of ethics as they reflected on their recent student teaching experiences. The findings explore how the participants depicted their constructed moral…

  1. Flexible Bistable Cholesteric Reflective Displays

    Science.gov (United States)

    Yang, Deng-Ke

    2006-03-01

    Cholesteric liquid crystals (ChLCs) exhibit two stable states at zero field condition-the reflecting planar state and the nonreflecting focal conic state. ChLCs are an excellent candidate for inexpensive and rugged electronic books and papers. This paper will review the display cell structure,materials and drive schemes for flexible bistable cholesteric (Ch) reflective displays.

  2. Reconfigurable antennas radiations using plasma Faraday cage

    OpenAIRE

    Barro , Oumar Alassane; Himdi , Mohamed; Lafond , Olivier

    2015-01-01

    International audience; This letter presents a new reconfigurable plasma antenna associated with a Faraday cage. The Faraday cage is realized using a fluorescent lamp. A patch antenna with a broadside radiation pattern or a monopole antenna with an end-fire radiation pattern , operating at 2.45 GHz, is placed inside Faraday cage. The performance of the reconfigurable system is observed in terms of input reflection coefficient, gain and radiation pattern via simulation and measurement. It is s...

  3. Reflection measurements for luminescent powders

    Science.gov (United States)

    Kroon, R. E.

    2018-04-01

    Luminescent materials are useful in applications varying from lighting and display technologies to document security features and medical research, amongst many others. Measurement of the excitation range is an important consideration, and absorption bands are often determined from a decrease in the measured diffuse reflectance of the material using a ultraviolet-visible (UV-vis) spectrophotometer with an integrating sphere. Such a system may provide questionable results when used to measure the reflectance of a luminescence material, which is demonstrated for a Tb doped silica phosphor, because the system cannot differentiate between the reflected light and luminescence. It is shown that more reliable results are achieved for this phosphor by measuring the reflectance using a synchronous zero-offset scan in a fluorescence spectrometer equipped with an integrating sphere. This method is therefore recommended instead of traditional reflectance measurements using a UV-vis spectrophotometer for luminescent powders.

  4. Radiation-induced centers in inorganic glasses

    International Nuclear Information System (INIS)

    Brekhovskikh, S.M.; Tyul'nin, V.A.

    1988-01-01

    The nature, structure and formation mechanisms of radiation-induced colour centers, EPR, luminescence, generated ionizing radiation in nonorganic oxide glasses are considered. Experimental material covering both fundamental aspects of radiation physics and glass chemistry, and aspects intimately connected with the creation of new materials with the given radiation-spectral characteristics, with possibilities to prepare radiation-stable and radiation-sensitive glasses is systematized and generalized. Considerable attention is paid to the detection of radiation-induced center binding with composition, glass structures redox conditions for their synthesis. Some new possibilities of practical application of glasses with radiation-induced centers, in particular, to record optical information are reflected in the paper

  5. Calculation of Reflectance and Transmittance of Coating With Optically Rough Surfaces

    International Nuclear Information System (INIS)

    El-Depsy, A.; Shawky, A.M.

    2011-01-01

    For ideal surfaces, components of the reflected beam are related to the components of the incident beam by Fresnel reflection equation. The surfaces encountered in engineering applications deviate from ideal as a result of roughness, oxidization and contamination; hence the Radiative properties of these real surfaces differ greatly from those predicted by electromagnetic theory. In regard to problems of radiative heat transfer; the roughness of surfaces may be divided into two categories: (1) small surface irregularities such that the incident radiation cannot undergo more than a single reflection, (2) deep cavities in which the incident radiation undergoes multi-reflection. The normally incident radiation from rough surface having small irregularities is reflected partly specularly and partly diffusely [1]. Kubelka-Munk theory (K-M) [2] describes optical characteristics (e.g. reflectance, transmittance and absorbance) by a variety of light scattering media including paints, textiles and papers, and It is widely used in various industrial applications. Moder developments in radiative transfer theory (RTT) enable the derivation of (K-M) parameters from first principles [3]. Kubelka and Munk proposed a theory based on a model of two light fluxes travelling in the forward and backward directions. Subsequently a number of authors refined the theory and compared it with experimental data [4]. Several authors attempted to relate the Kubelka- Munk coefficients to the transport coefficients [5,6

  6. Radiation injury

    International Nuclear Information System (INIS)

    Hubner, K.F.

    1988-01-01

    Radiation accidents and incidents continue to be of great interest and concern to the public. Issues such as the threat of nuclear war, the Chernobyl reactor accident, or reports of sporadic incidences of accidental radiation exposure keep this interest up and maintain a high level of fear among the public. In this climate of real concern and radiation phobia, physicians should not only be prepared to answer questions about acute or late effects of ionizing radiation, but also be able to participate in the initial assessment and management of individuals who have been exposed to ionizing radiation or contaminated with radioactive material. Some of the key facts about radiation injury and its medical treatment are discussed by the author

  7. Cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Capdevielle, J N

    1984-01-01

    First, the different instruments and techniques of cosmic particle detection are presented. Then the passage of the cosmic particles through the atmosphere is studied: electrons, photons, muons. The collective behavior of the different categories is also studied, the electromagnetic cascade is distinguished from the hadron cascade. Through the principal physical properties of the radiation and the medium, the ''mean'' aspects of the radiation are then successively dealt with out of the atmosphere, at different altitudes until the sea level, then at great depths. A chapter is devoted to cosmic radiation of more than 10,000 GeV, studied separately. Then solar radiation in universe is studied through their propagation in solar system and their origin. At last, the cosmic radiation effects are studied in environment (cosmic biophysics) and some applications of cosmic radiation are presented.

  8. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1976-01-01

    The risk of iatrogenic tumors with radiation therapy is so outweighed by the benefit of cure that estimates of risk have not been considered necessary. However, with the introduction of chemotherapy, combined therapy, and particle radiation therapy, the comparative risks should be examined. In the case of radiation, total dose, fractionation, dose rate, dose distribution, and radiation quality should be considered in the estimation of risk. The biological factors that must be considered include incidence of tumors, latent period, degree of malignancy, and multiplicity of tumors. The risk of radiation induction of tumors is influenced by the genotype, sex, and age of the patient, the tissues that will be exposed, and previous therapy. With chemotherapy the number of cells at risk is usually markedly higher than with radiation therapy. Clearly the problem of the estimation of comparative risks is complex. This paper presents the current views on the comparative risks and the importance of the various factors that influence the estimation of risk

  9. Orbiter radiator panel solar focusing test

    Science.gov (United States)

    Howell, H. R.; Rankin, J. G.

    1983-01-01

    Test data are presented which define the area around the Orbiter radiator panels for which the solar reflections are concentrated to one-sun or more. The concave shape of the panels and their specular silver/Teflon coating causes focusing of the reflected solar energy which could have adverse heating effects on equipment or astronaut extravehicular activity (EVA) in the vicinity of the radiator panels. A room ambient test method was utilized with a one-tenth scale model of the radiator panels.

  10. Hawking radiation

    Science.gov (United States)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  11. Radiation meter

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, P H

    1990-05-30

    Measuring means comprising first and second silicon PIN diode detectors both being covered with a thin layer of conducting material and the second detector being additionally covered with a relatively thick layer of material, the thickness being chosen such that beta radiation dose rate can be measured in beta radiation fields of high or medium energy, and in the presence of X and gamma radiation. (author). 2 figs.

  12. Radiation regulation

    International Nuclear Information System (INIS)

    Braithwaite, J.; Grabosky, P.

    1985-01-01

    The five main areas of radiation regulation considered are radiation exposure in the mining of uranium and other minerals, exposure in the use of uranium in nuclear reactors, risks in the transport of radioactive materials and hazards associated with the disposal of used materials. In Australia these problems are regulated by mines departments, the Australian Atomic Energy Commission and radiation control branches in state health departments. Each of these instutional areas of regulation is examined

  13. Radiation chemistry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1973-07-01

    Research progress is reported on radiation chemistry of heavy elements that includes the following topics: radiation chemistry of plutonium in nitric acid solutions (spectrophotometric analysis and gamma radiolysis of Pu(IV) and Pu(VI) in nitric acid solution); EPR studies of intermediates formed in radiolytic reactions with aqueous medium; two-phase radiolysis and its effect on the distribution coefficient of plutonium; and radiation chemistry of nitric acid. (DHM)

  14. Radiation protection

    International Nuclear Information System (INIS)

    1989-01-01

    A NRPB leaflet in the 'At-a-Glance' series explains in a simple but scientifically accurate way what radiation is, the biological effects and the relative sensitivity of different parts of the human body. The leaflet then discusses radiation protection principles, radiation protection in the UK and finally the effectiveness of this radiation protection as judged by a breakdown of the total dose received by an average person in the UK, a heavy consumer of Cumbrian seafood, an average nuclear industry worker and an average person in Cornwall. (UK)

  15. Radiation medicine

    International Nuclear Information System (INIS)

    1991-01-01

    This booklet has been produced by UKAEA and the Marie Curie Memorial Foundation to give some basic information about what radiation is and how it is used in day to day diagnosis and treatment. It will be of interest to people undergoing treatment, their relatives and friends, and anyone who wants to know more about this important area. After a brief historical introduction the booklet explains what radiation is, the natural and man-made sources of radiation, how it is produced and how X-rays are used in medical diagnosis and treatment. The radiation protection measures taken and safety standards followed are mentioned. (author)

  16. GRAVITATIONAL RADIATION

    Directory of Open Access Journals (Sweden)

    Metin SALTIK

    1996-03-01

    Full Text Available According to classical electromagnetic theory, an accelerated charge or system of charges radiates electromagnetic waves. In a radio transmitter antenna charges are accelerated along the antenna and release electromagnetic waves, which is radiated at the velocity of light in the surrounding medium. All of the radio transmitters work on this principle today. In this study an analogy is established between the principles by which accelerated charge systems markes radiation and the accelerated mass system, and the systems cousing gravitational radiation are investigated.

  17. Synchrotron radiation

    International Nuclear Information System (INIS)

    Farge, Y.

    1982-01-01

    Synchrotron radiation is produced by electrons accelerated near the velocity of light in storage rings, which are used for high energy Physics experiments. The radiation light exhibits a wide spread continuous spectrum ranging from 01 nanometre to radiofrequency. This radiation is characterized by high power (several kilowatts) and intense brightness. The paper recalls the emission laws and the distinctive properties of the radiation, and gives some of the numerous applications in research, such as molecular spectroscopy, X ray diffraction by heavy proteins and X ray microlithography in LVSI circuit making [fr

  18. Electro-optic study of PZT ferroelectric ceramics using modulation of reflected light

    Science.gov (United States)

    Kniazkov, A. V.

    2016-04-01

    Electro-optic coefficients of variations in the refractive index of PZT and PLZT ceramic materials induced by ac electric field are estimated using modulation of reflected light. The electro-optic coefficients of PLZT ceramics measured with the aid of conventional birefringence using the phase shift of transmitted radiation and the proposed method of birefringence using the modulation of reflected light are compared.

  19. CPV system based on NIR reflecting lamellae integrated into a greenhouse: Optimizing of Optics

    NARCIS (Netherlands)

    Piet Sonneveld; Gert-Jan Swinkels

    2010-01-01

    In an previous research project a new type of greenhouse with an integrated concentrated photovoltaic system (CPV) was developed which has an integrated filter for reflecting the near infrared radiation (NIR) to the greenhouse and exploiting this radiation in a solar energy system. The performance

  20. X ray reflection masks: Manufacturing, characterization and first tests

    Science.gov (United States)

    Rahn, Stephen

    1992-09-01

    SXPL (Soft X-ray Projection Lithography) multilayer mirrors are characterized, laterally structured and then used as reflection masks in a projecting lithography procedure. Mo/Si-multilayer mirrors with a 2d in the region of 14 nm were characterized by Cu-k(alpha) grazing incidence as well as soft X-ray normal incidence reflectivity measurements. The multilayer mirrors were patterned by reactive ion etching with CF4 using a photoresist as etch mask, thus producing X-ray reflection masks. The masks were tested at the synchrotron radiation laboratory of the electron accelerator ELSA. A double crystal X-ray monochromator was modified so as to allow about 0.5 sq cm of the reflection mask to be illuminated by white synchrotron radiation. The reflected patterns were projected (with an energy of 100 eV) onto a resist and structure sizes down to 8 micrometers were nicely reproduced. Smaller structures were distorted by Fresnel-diffraction. The theoretically calculated diffraction images agree very well with the observed images.

  1. Radiation and radiation protection; Strahlung und Strahlenschutz

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomaeus, Melanie (comp.)

    2017-04-15

    The publication of the Bundesamt fuer Strahlenschutz covers the following issues: (i) Human beings in natural and artificial radiation fields; (ii) ionizing radiation: radioactivity and radiation, radiation exposure and doses; measurement of ionizing radiation, natural radiation sources, artificial radiation sources, ionizing radiation effects on human beings, applied radiation protection, radiation exposure of the German population, radiation doses in comparison; (iii) non-ionizing radiation; low-frequency electric and magnetic fields, high-frequency electromagnetic fields, optical radiation; (iiii) glossary, (iv) units and conversion.

  2. Radiation myelopathy

    International Nuclear Information System (INIS)

    Berlit, P.

    1987-01-01

    After a review of the world literature, the case histories of 43 patients with radiation myelopathy are analyzed. In 1 patient there was a radiation injury of the medulla oblongata, in 2, cervical, in 28, thoracic, and in 12, lumbosacral. In the medulla oblongata lesion an alternans syndrome resulted. The patients with cervical and thoracic radiation myelopathies presented with a Brown-Sequard syndrome, a spinalis anterior syndrome or a transversal syndrome with pyramidal and spinothalamic tract involvement as the most prominent signs. For this group the term 'pyramidal-spinothalamic radiation myelopathy' is proposed. In lumbosacral radiation lesions a pure anterior horn syndrome may lead to spinothalamic tract involvement and the development of a cauda conus syndrome. The clinical presentation of these cases suggests that the location of the radiation lesion is most likely the region of the conus medullaris. The most frequent initial symptom was dysesthesia; the patients complained of burning pain or a feeling of coldness. Usually the neurological deficits were progressive, in pyramidal-spinothalamic radiation myelopathy over 12 months in average, in lumbosacral radiation lesions up to 10 years. The latent period between the finish of radiation therapy and the first neurological signs was 8 months (median) in cervical and thoracic myelopathy and 33 months in lumbosacral lesions. For the entire group of 43 patients there was an inverse relationship between the radiation dose (ret) and the latent period. A positive relation could be demonstrated between the age of patients at the time of radiation therapy and the latent period. Patients simultaneously receiving cytostatic drugs presented after a longer latent period than the remaining group. (orig./MG)

  3. DIRC, the internally reflecting ring imaging Cherenkov detector for BABAR

    International Nuclear Information System (INIS)

    Adam, I.; Aston, D.

    1997-11-01

    The DIRC is a new type of Cherenkov imaging device that will be used for the first time in the BABAR detector at the asymmetric B-factory, PEP-II. It is based on total internal reflection and uses long, rectangular bars made from synthetic fused silica as Cherenkov radiator and light guide. The principles of the DIRC ring imaging Cherenkov technique are explained and results from the prototype program are presented. Its choice for the BABAR detector particle identification system is motivated, followed by a discussion of the quartz radiator properties and the detector design

  4. Concepts of radiation protection

    International Nuclear Information System (INIS)

    2013-01-01

    This seventh chapter presents the concepts and principles of safety and radiation protection, emergency situations; NORM and TENORM; radiation protection care; radiation protection plan; activities of the radiation protection service; practical rules of radiation protection and the radiation symbol

  5. Radiation exposure and radiation protection

    International Nuclear Information System (INIS)

    Heuck, F.; Scherer, E.

    1985-01-01

    The present volume is devoted to the radiation hazards and the protective measures which can be taken. It describes the current state of knowledge on the changes which exposure to ionizing rays and other forms of physical energy can induce in organs and tissues, in the functional units and systems of the organism. Special attention is paid to general cellular radiation biology and radiation pathology and to general questions of the biological effects of densely ionizing particle radiation, in order to achieve a better all-round understanding of the effects of radiation on the living organism. Aside from the overviews dealing with the effects of radiation on the abdominal organs, urinary tract, lungs, cerebral and nervous tissue, bones, and skin, the discussion continues with the lymphatic system, the bone marrow as a bloodforming organ, and the various phases of reaction in the reproductive organs, including damage and subsequent regeneration. A special section deals with environmental radiation hazards, including exposure to natural radiation and the dangers of working with radioactive substances, and examines radiation catastrophes from the medical point of view. Not only reactor accidents are covered, but also nuclear explosions, with exhaustive discussion of possible damage and treatment. The state of knowledge on chemical protection against radiation is reviewed in detail. Finally, there is thorough treatment of the mechanism of the substances used for protection against radiation damage in man and of experience concerning this subject to date. In the final section of the book the problems of combined radiotherapy are discussed. The improvement in the efficacy of tumor radiotherapy by means of heavy particles is elucidated, and the significance of the efficacy of tumor therapy using electron-affinitive substances is explained. There is also discussion of the simultaneous use of radiation and pharmaceuticals in the treatment of tumors. (orig./MG) [de

  6. Reflection measurements of microwave absorbers

    Science.gov (United States)

    Baker, Dirk E.; van der Neut, Cornelis A.

    1988-12-01

    A swept-frequency interferometer is described for making rapid, real-time assessments of localized inhomogeneities in planar microwave absorber panels. An aperture-matched exponential horn is used to reduce residual reflections in the system to about -37 dB. This residual reflection is adequate for making comparative measurements on planar absorber panels whose reflectivities usually fall in the -15 to -25 dB range. Reflectivity measurements on a variety of planar absorber panels show that multilayer Jaumann absorbers have the greatest inhomogeneity, while honeycomb absorbers generally have excellent homogeneity within a sheet and from sheet to sheet. The test setup is also used to measure the center frequencies of resonant absorbers. With directional couplers and aperture-matched exponential horns, the technique can be easily applied in the standard 2 to 40 GHz waveguide bands.

  7. Ibuanyidanda (Complementary Reflection), Communalism and ...

    African Journals Online (AJOL)

    Fr. Prof. Asouzu

    Glossary of Igbo Terms and Phrases ihe ahụ na anya ... other words, it is in mutual dependence that the feeling of intimacy found among kindred ..... Complementary Reflection, Communalism and Theory Formulation in African Philosophy 25.

  8. Worldwide Marine Seismic Reflection Profiles

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC maintains a large volume of both Analog and Digital seismic reflection data. Currently only a limited number of lines are available online. Digital data include...

  9. Reflective Methodology: The Beginning Teacher

    Science.gov (United States)

    Templeton, Ronald K.; Siefert, Thomas E.

    1970-01-01

    Offers a variety of specific techniques which will help the beginning teacher to implement reflective methodology and create an inquiry-centered classroom atmosphere, at the same time meeting the many more pressing demands of first-year teaching. (JES)

  10. High-resolution reflection spectroscopy

    International Nuclear Information System (INIS)

    Ducloy, Martial

    1997-01-01

    In this article some recent developments in selective reflection spectroscopy is reviewed and the various ways to extend Doppler free techniques to this spectroscopic field is discussed. Its main feature is to probe atomic gas close to the cell boundaries

  11. Radiation Effects Research Foundation

    International Nuclear Information System (INIS)

    1979-01-01

    The last day of March 1978 marked the completion of the first 3 years of operation of the Radiation Effects Research Foundation in Hiroshima and Nagasaki. RERF was established on 1 April 1975 as successor to the Atomic Bomb Casualty Commission which had been in continuous operation since 1947. This record of the first 3 years of operation consists of selected reports and other documents prepared in the course of conducting the business of RERF and includes a brief history, a late radiation effects that might be conducted at RERF. The wisdom and thought given to the research program and its operation by the Scientific Council and the Board of Directors is reflected in the minutes of their meetings which are included in the Appendix. (Mori, K.)

  12. Deterioration of reflecting coatings by intermetallic diffusion.

    Science.gov (United States)

    Hunter, W R; Mikes, T L; Hass, G

    1972-07-01

    Gold diffraction gratings overcoated with Al + MgF(2) to increase their efficiency in the vacuum ultraviolet suffered a severe loss in efficiency within six months to a year after coating; for example, from 50% to 2% at lambda1216 A. The cause of this loss was assumed to be interdiffusion of Au and Al; therefore, a more complete study of Au-Al film combinations was performed. The coatings were aged at room and elevated temperatures. Reflectance measurements were made in the visible and vacuum ultraviolet spectral regions. For wavelengths longer than lambda900 A, the measurements show very little change until the diffusion boundary reaches the penetration depth of the radiation. If Al is the first surface layer, however, reflectance measurements at lambda584 A permit measuring the progress of the diffusion boundary toward the Al surface because of the low absorptance of Al at this wavelength. Interdiffusion can be effectively eliminated by the use of thin dielectric layers uch as SiO and the natural oxide of Al. Such protected coatings have been exposed for one week at a temperature of 170 degrees C with no visible sign of diffusion, whereas a similar coating without the barrier layer would become useless in less than 1 h. Some preliminary studies have been made with Pt-Al film combinations.

  13. Radiation signatures

    International Nuclear Information System (INIS)

    McGlynn, S.P.; Varma, M.N.

    1992-01-01

    A new concept for modelling radiation risk is proposed. This concept is based on the proposal that the spectrum of molecular lesions, which we dub ''the radiation signature'', can be used to identify the quality of the causal radiation. If the proposal concerning radiation signatures can be established then, in principle, both prospective and retrospective risk determination can be assessed on an individual basis. A major goal of biophysical modelling is to relate physical events such as ionization, excitation, etc. to the production of radiation carcinogenesis. A description of the physical events is provided by track structure. The track structure is determined by radiation quality, and it can be considered to be the ''physical signature'' of the radiation. Unfortunately, the uniqueness characteristics of this signature are dissipated in biological systems in ∼10 -9 s. Nonetheless, it is our contention that this physical disturbance of the biological system eventuates later, at ∼10 0 s, in molecular lesion spectra which also characterize the causal radiation. (author)

  14. Background radiation

    International Nuclear Information System (INIS)

    Arnott, D.

    1985-01-01

    The effects of background radiation, whether natural or caused by man's activities, are discussed. The known biological effects of radiation in causing cancers or genetic mutations are explained. The statement that there is a threshold below which there is no risk is examined critically. (U.K.)

  15. Ionizing radiations

    International Nuclear Information System (INIS)

    Anon.

    1999-01-01

    This is an update about the radiological monitoring in base nuclear installations. A departmental order of the 23. march 1999 (J.O.28. april, p.6309) determines the enabling rules by the Office of Protection against Ionizing Radiations of person having at one's disposal the results with names of individual exposure of workers put through ionizing radiations. (N.C.)

  16. Radiation hematology

    International Nuclear Information System (INIS)

    Zherbin, E.A.; Chukhlovin, A.B.

    1989-01-01

    State-of-the-Art ofl radiation hematology and review of the problems now facing this brauch of radiobiology and nuclear medicine are presented. Distortion of division and maturation of hemopoiesis parent cells is considered as main factor of radiopathology for hematopoetic system. Problems of radiation injury and functional variation of hematopoetic microenvironment cell populations are discussed. 176 figs.; 23 figs.; 18 tabs

  17. Radiation oncology

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The Radiation Oncology Division has had as its main objectives both to operate an academic training program and to carry out research on radiation therapy of cancer. Since fiscal year 1975, following a directive from ERDA, increased effort has been given to research. The research activities have been complemented by the training program, which has been oriented toward producing radiation oncologists, giving physicians short-term experience in radiation oncology, and teaching medical students about clinical cancer and its radiation therapy. The purpose of the research effort is to improve present modalities of radiation therapy of cancer. As in previous years, the Division has operated as the Radiation Oncology Program of the Department of Radiological Sciences of the University of Puerto Rico School of Medicine. It has provided radiation oncology support to patients at the University Hospital and to academic programs of the University of Puerto Rico Medical Sciences Campus. The patients, in turn, have provided the clinical basis for the educational and research projects of the Division. Funding has been primarily from PRNC (approx. 40%) and from National Cancer Institute grants channeled through the School of Medicine (approx. 60%). Special inter-institutional relationships with the San Juan Veterans Administration Hospital and the Metropolitan Hospital in San Juan have permitted inclusion of patients from these institutions in the Division's research projects. Medical physics and radiotherapy consultations have been provided to the Radiotherapy Department of the VA Hospital

  18. Synchrotron radiation

    International Nuclear Information System (INIS)

    Nave, C.; Quinn, P.; Blake, R.J.

    1988-01-01

    The paper on Synchrotron Radiation contains the appendix to the Daresbury Annual Report 1987/88. The appendix is mainly devoted to the scientific progress reports on the work at the Synchrotron Radiation Source in 1987/8. The parameters of the Experimental Stations and the index to the Scientific Reports are also included in the appendix. (U.K.)

  19. Radiation Protection

    International Nuclear Information System (INIS)

    Loos, M.

    2002-01-01

    Major achievements of SCK-CEN's Radiation Protection Department in 2001 are described. The main areas for R and D of the department are enviromnental remediation, emergency planning, radiation protection research, low-level radioactvity measurements, safeguards and physics measurements, decision strategy research and policy support and social sciences in nuclear research. Main achievements for 2001 in these areas are reported

  20. Ionizing radiation

    Science.gov (United States)

    Tobias, C. A.; Grigoryev, Y. G.

    1975-01-01

    The biological effects of ionizing radiation encountered in space are considered. Biological experiments conducted in space and some experiences of astronauts during space flight are described. The effects of various levels of radiation exposure and the determination of permissible dosages are discussed.

  1. Radiation energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Bei Tse; Rabl, A

    1977-02-10

    The invention deals with a concentrating solar collector. Collectors of this kind often have considerable natural convection losses which are due, among other facts, to the location of the energy absorber at the outlet with the heated surface of the absorber facing the inlet opening of the collector. According to the invention, the collector is designed in such manner that the absorber is located inside a space in such a way that the radiation emitted by the absorber is reflected back to the absorber with the aid of mirror surfaces. Various designs are described.

  2. Analytic Reflected Lightcurves for Exoplanets

    Science.gov (United States)

    Haggard, Hal M.; Cowan, Nicolas B.

    2018-04-01

    The disk-integrated reflected brightness of an exoplanet changes as a function of time due to orbital and rotational motion coupled with an inhomogeneous albedo map. We have previously derived analytic reflected lightcurves for spherical harmonic albedo maps in the special case of a synchronously-rotating planet on an edge-on orbit (Cowan, Fuentes & Haggard 2013). In this letter, we present analytic reflected lightcurves for the general case of a planet on an inclined orbit, with arbitrary spin period and non-zero obliquity. We do so for two different albedo basis maps: bright points (δ-maps), and spherical harmonics (Y_l^m-maps). In particular, we use Wigner D-matrices to express an harmonic lightcurve for an arbitrary viewing geometry as a non-linear combination of harmonic lightcurves for the simpler edge-on, synchronously rotating geometry. These solutions will enable future exploration of the degeneracies and information content of reflected lightcurves, as well as fast calculation of lightcurves for mapping exoplanets based on time-resolved photometry. To these ends we make available Exoplanet Analytic Reflected Lightcurves (EARL), a simple open-source code that allows rapid computation of reflected lightcurves.

  3. Radiation exposure

    International Nuclear Information System (INIS)

    Dalton, L.K.

    1991-01-01

    The book gives accounts of some social and environmental impacts of the developing radiation industries, including the experiences of affected communities and individuals. Its structure is based on a division which has been made between nuclear and non-nuclear radiation sources, because they create distinctly different problems for environmental protection and so for public health policy. The emissions from electronic and electrical installations - the non-nuclear radiations - are dealt with in Part I. Emissions from radioactive substances - the nuclear radiations - are dealt with in Part II. Part III is for readers who want more detailed information about scientific basis of radiation-related biological changes and their associated health effects. 75 refs., 9 tabs., 7 figs., ills

  4. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    Adams, G.E.

    1987-01-01

    In this contribution about carcinogenesis induced by ionizing radiation some radiation dose-response relationships are discussed. Curves are shown of the relation between cell survival and resp. low and high LET radiation. The difference between both curves can be ascribed to endogenous repair mechanisms in the cell. The relation between single-gen mutation frequency and the surviving fractions of irradiated cells indicates that these repairing mechanisms are not error free. Some examples of reverse dose-response relationships are presented in which decreasing values of dose-rate (LET) correspond with increasing radiation induced cell transformation. Finally some molecular aspects of radiation carcinogenesis are discussed. (H.W.). 22 refs.; 4 figs

  5. Radiation sickness

    International Nuclear Information System (INIS)

    Endoh, Masaru; Ishida, Yusei; Saeki, Mitsuaki

    1983-01-01

    The frequency of radiation sickness in 1,060 patients treated at our Department was 12.8 percent. It was frequent in patients with brain cancer (12 percent), whole spine cancer (47 percent), uterus cancer (28 percent), lung cancer (22 percent) and esophagus cancer (12 percent). Radiation sickness following X-irradiation was studied in its relation to patient's age, size of radiation fields, dosis and white blood cell count. However, we could not find any definite clinical feature relevant to occurrence. There are many theories published concerning the mechanism of radiation sickness. Clinical experiences have shown that radiation sickness cannot be explained by one theory alone but by several theories such as those based on psychology, stress or histamine. (author)

  6. Radiation safety

    International Nuclear Information System (INIS)

    Auxier, J.A.

    1977-01-01

    Data available on the biological effects of radiation on man are reviewed, with emphasis on dose response to low LET and high LET radiation sources, and the effects of dose rate. Existing guides for radiation protection were formulated largely on the basis of tumor induction in the bone of radium dial painters, but the ICRP/NCRP annual dose guides of 5 rem/yr are of the same general magnitude as the doses received in several parts of the world from the natural radiation environment. Because of the greater sensitivity of rapidly dividing cells and the assumption that radiation occupations would not begin before the age of eighteen, maximum exposure levels were set as 5 (N-18) rem/yr, where N is the exposed worker's age in years. However, in the case of the natural radiation environment, exposure commences, in a sense, with the exposure of the ovum of the individual's mother; and the ovum is formed during the fetal development of the mother. In occupational exposures, the professional health physicist has always practiced the as low as practical philosophy, and exposures have generally averaged far below the guidelines. The average annual exposure of the radiation worker in modern plants and laboratories is approximately equal to the average natural radiation environment exposure rate and far lower than the natural radiation environment in many parts of the world. There are numerous complications and uncertainties in quantifying radiation effects on humans, however, the greatest is that due to having to extrapolate from high dose levels at which effects have been measured and quantified, to low levels at which most exposures occur but at which no effects have been observed

  7. Radiation safety

    International Nuclear Information System (INIS)

    Van Riessen, A.

    2002-01-01

    Full text: Experience has shown that modem, fully enclosed, XRF and XRD units are generally safe. This experience may lead to complacency and ultimately a lowering of standards which may lead to accidents. Maintaining awareness of radiation safety issues is thus an important role for all radiation safety officers. With the ongoing progress in technology, a greater number of radiation workers are more likely to use a range of instruments/techniques - eg portable XRF, neutron beam analysis, and synchrotron radiation analysis. The source for each of these types of analyses is different and necessitates an understanding of the associated dangers as well as use of specific radiation badges. The trend of 'suitcase science' is resulting in scientists receiving doses from a range of instruments and facilities with no coordinated approach to obtain an integrated dose reading for an individual. This aspect of radiation safety needs urgent attention. Within Australia a divide is springing up between those who work on Commonwealth property and those who work on State property. For example a university staff member may operate irradiating equipment on a University campus and then go to a CSIRO laboratory to operate similar equipment. While at the University State regulations apply and while at CSIRO Commonwealth regulations apply. Does this individual require two badges? Is there a need to obtain two licences? The application of two sets of regulations causes unnecessary confusion and increases the workload of radiation safety officers. Radiation safety officers need to introduce risk management strategies to ensure that both existing and new procedures result in risk minimisation. A component of this strategy includes ongoing education and revising of regulations. AXAA may choose to contribute to both of these activities as a service to its members as well as raising the level of radiation safety for all radiation workers. Copyright (2002) Australian X-ray Analytical

  8. Radiation in the human environment: health effects, safety and acceptability

    International Nuclear Information System (INIS)

    Gonzalez, A.J.; Anderer, J.

    1990-01-01

    This paper reports selectively on three other aspects of radiation (used throughout to mean ionizing radiation) in the human environment: the human health effects of radiation, radiation safety policy and practices, and the acceptability of scientifically justified practices involving radiation exposures. Our argument is that the science of radiation biology, the judgemental techniques of radiation safety, and the social domain of radiation acceptability express different types of expertise that should complement - and not conflict with or substitute for - one another. Unfortunately, communication problems have arisen among these three communities and even between the various disciplines represented within a community. These problems have contributed greatly to the misperceptions many people have about radiation and which are frustrating a constructive dialogue on how radiation can be harnessed to benefit mankind. Our analysis seeks to assist those looking for a strategic perspective from which to reflect on their interaction with practices involving radiation exposures. (author)

  9. Design of Reflective, Photonic Shields for Atmospheric Reentry

    Science.gov (United States)

    Komarevskiy, Nikolay; Shklover, Valery; Braginsky, Leonid; Hafner, Christian; Fabrichnaya, Olga; White, Susan; Lawson, John

    2010-01-01

    We present the design of one-dimensional photonic crystal structures, which can be used as omnidirectional reflecting shields against radiative heating of space vehicles entering the Earth's atmosphere. This radiation is approximated by two broad bands centered at visible and near-infrared energies. We applied two approaches to find structures with the best omnidirectional reflecting performance. The first approach is based on a band gap analysis and leads to structures composed of stacked Bragg mirrors. In the second approach, we optimize the structure using an evolutionary strategy. The suggested structures are compared with a simple design of two stacked Bragg mirrors. Choice of the constituent materials for the layers as well as the influence of interlayer diffusion at high temperatures are discussed.

  10. Effect of reflecting modes on combined heat transfer within an anisotropic scattering slab

    International Nuclear Information System (INIS)

    Yi Hongliang; Tan Heping; Lu Yiping

    2005-01-01

    Under various interface reflecting modes, different transient thermal responses will occur in the media. Combined radiative-conductive heat transfer is investigated within a participating, anisotropic scattering gray planar slab. The two interfaces of the slab are considered to be diffuse and semitransparent. Using the ray tracing method, an anisotropic scattering radiative transfer model for diffuse reflection at boundaries is set up, and with the help of direct radiative transfer coefficients, corresponding radiative transfer coefficients (RTCs) are deduced. RTCs are used to calculate the radiative source term in energy equation. Transient energy equation is solved by the full implicit control-volume method under the external radiative-convective boundary conditions. The influences of two reflecting modes including both specular reflection and diffuse reflection on transient temperature fields and steady heat flux are examined. According to numerical results obtained in this paper, it is found that there exits great difference in thermal behavior between slabs with diffuse interfaces and that with specular interfaces for slabs with big refractive index

  11. Reflections

    Indian Academy of Sciences (India)

    physics, and to whom he always remained close - his sister Maja. .... moved to Munich at the beginning of 1882, when Albert was barely two years old. ... This was demonstrated during a further change in the sphere of activity of .... As is well known, in Germany one uses the polite form "Sie" for adults and for people who.

  12. Reflections

    Indian Academy of Sciences (India)

    2004-04-01

    Apr 1, 2004 ... journal Current Science, Vol 61, 1991, pp.594-600. It is an ... could be explained as mere imperfections in the fossil record. .... would almost seem that exposure to the rigours of the climate had quickened the pace ... would be interesting to know whether this telescoping effect is the outward manifesta-.

  13. Reflections

    Indian Academy of Sciences (India)

    making computer programs 'human like' by building in learning and ... discussed the problems of control and communication in the living organism and the machine. ... To be effective in warding off disastrous consequences, our understanding.

  14. Reflections

    Indian Academy of Sciences (India)

    not only in linguistics hut also in allied fields, splitting social scientists into t\\VO groups, Chomskyan and others. ... views on language, IlO\\\\"knoVv'Il as 'Standard Theory', generated a ... For the human mind, learning is a kind of reminiscence.

  15. Reflections

    Indian Academy of Sciences (India)

    future seemed secure, and there was such complete harmony of character between ... was at once so taken with the idea that he was able to persuade Hermann Einstein to .... A liberal spirit, undogmatic in matters of religion, brought by both.

  16. Reflections

    Indian Academy of Sciences (India)

    Of what lasting benefit has been man's use of science and of the new instruments which his research .... future moves about the laboratory or the field, every time he looks at something worthy of ... Yet the speed of action, the intricacy of .... physician, puzzled by a patient's reactions, strikes the trail established in studying an.

  17. Reflections

    DEFF Research Database (Denmark)

    du Gay, Paul; Vikkelsø, Signe

    2012-01-01

    The notion of ‘change’ has become pervasive in contemporary organizational discourse. On the one hand, change is represented as an organizational imperative that increasingly appears to trump all other concerns. On the other hand, change is addressed as an abstract, generic entity that can be the...

  18. Reflections

    Indian Academy of Sciences (India)

    Newton that there was a transition to the understanding and explanation of natural .... All of this again is accessible to human understanding, and new laws of nature couched in ..... able limits to communication with other individuals.

  19. Reflections

    Indian Academy of Sciences (India)

    The modem picture of the basic constituents and their interactions is described by the so called ... According to him, however great the ... Finally, it is good to remember the words of Bhabha that only science and technology can solve the.

  20. Applying measured reflection from the ground to simulations of thermal perfromance of solar collectors

    DEFF Research Database (Denmark)

    Dragsted, Janne; Furbo, Simon

    2009-01-01

    representation of the reflection from the ground. In this study a more accurate description of the albedo is obtained based on detailed measurements from a solar hat, installed at ASIAQ’s climate station in Sisimiut, Greenland. The solar hat measures the global radiation on horizontal, the total radiation......Solar radiation on tilted and vertical surfaces in the Arctic is, in large parts of the year, strongly influenced by reflection from snow. In connection with planning and optimization of energy efficient buildings and solar energy systems in the Arctic, it is important to have an accurate...... on vertical surfaces facing north, south, east and west, and radiation reflected from the ground on vertical surfaces facing north, south, east and west. Based on measured data from 2004-2007 the albedo is determined for each month of the year as a function of the difference between the solar azimuth...

  1. Influence of reflectance from flat aluminum concentrators on energy efficiency of PV/Thermal collector

    International Nuclear Information System (INIS)

    Kostic, Ljiljana T.; Pavlovic, Tomislav M.; Pavlovic, Zoran T.

    2010-01-01

    In this paper the results of the influence of reflectance from flat plate solar radiation concentrators made of Al sheet and Al foil on energy efficiency of PV/Thermal collector are presented. The total reflectance from concentrators made of Al sheet and Al foil is almost the same, but specular reflectance which is bigger in concentrators made of Al foil results in increase of solar radiation intensity concentration factor. With the increase of solar radiation intensity concentration factor, total daily thermal and electrical energy generated by PV/Thermal collector with concentrators increase. In this work also optimal position of solar radiation concentrators made of Al sheet and Al foil and appropriate thermal and electrical efficiency of PV/Thermal collector have been determined. Total energy generated by PV/Thermal collector with concentrators made of Al foil in optimal position is higher than total energy generated by PV/Thermal collector with concentrators made of Al sheet.

  2. Radiation therapy

    International Nuclear Information System (INIS)

    Bader, J.L.; Glatstein, E.

    1987-01-01

    The radiation oncologist encounters the critically ill immunosuppressed patient in four settings. First, the newly diagnosed cancer patient presents for initial evaluation and treatment, with immunosuppression from the cancer itself, malnutrition, concomitant infectious disease, prior drug or alcohol abuse or other medical problems. Second, the previously treated cancer patient presents with metastatic or recurrent primary cancer causing local symptoms. Immune dysfunction in this setting may be due to prior chemotherapy and/or radiation as well as any of the original factors. Third, the patient previously treated with radiation presents with a life-threatening problem possibly due to complications of prior therapy. In this setting, the radiation oncologist is asked to evaluate the clinical problem and to suggest whether radiation might be causing part or all of the problem and what can be done to treat these sequelae of radiation. Fourth, the patient with a benign diagnosis (not cancer) is seen with a problem potentially emeliorated by radiation (e.g., kidney transplant rejection, preparation for transplant, or intractable rheumatoid arthritis). This chapter reviews these four issues and presents clinical and radiobiologic principles on which recommendations for therapy are based

  3. Effect of retro-reflective materials on temperature environment in tents

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    2017-03-01

    Full Text Available Due to the low thermal inertia and poor thermal insulation of ultrathin envelope in tents, its indoor temperature environment is extremely bad and its occupants are tormented. Especially under the high solar radiation, both indoor air temperature and inner surface radiation temperature increase rapidly. And thereby, decreasing radiation heat gain in summer is necessary to refine indoor temperature environment in tents. Retro-reflective materials make it a reasonable choice due to their high reflectivity for solar radiation. To reveal the temperature environment improvement of tents by integrating with retro-reflective materials, a comparative experiment is carried out under the summer climatic conditions of Chengdu city, China. Experimental results show that due to integrating with retro-reflective materials, indoor air peak temperature in the tent can be reduced by more than 7.7 °C, while inner surface radiant temperature can be lowered up to 4.8 °C in the day time. It shows retro-reflective materials could refine indoor temperature environment in tents. Through a comparison of the walls in different orientations, on which retro-reflective materials are covered, the top, east and north walls are found to be better choices, while the north wall is the worst one for retro-reflective materials.

  4. Radiation physics

    International Nuclear Information System (INIS)

    Nam, Sang Hui

    1991-02-01

    This book deals with radiation physics, which introduces atomic theory and an atomic nucleus of materials, conception of an atom and materials, wave and particle, X ray generation and character, a radioactive element and change law, nature of radioactivity, neutron rays, fission, alpha collapse and beta collage and a neutrino collapse of artificial radioactivity such as collapse of artificial nucleus and artificial radioactivity and radiative capture, interaction with materials like interaction between a charged particle and materials and interaction among X-ray, r-ray and materials, radiation of quantity and unit and a charged particle accelerator.

  5. Synchrotron radiation

    CERN Document Server

    Kunz, C

    1974-01-01

    The production of synchrotron radiation as a by-product of circular high-energy electron (positron) accelerators or storage rings is briefly discussed. A listing of existing or planned synchrotron radiation laboratories is included. The following properties are discussed: spectrum, collimation, polarization, and intensity; a short comparison with other sources (lasers and X-ray tubes) is also given. The remainder of the paper describes the experimental installations at the Deutsches Elektronen-Synchrotron (DESY) and DORIS storage rings, presents a few typical examples out of the fields of atomic, molecular, and solid-state spectroscopy, and finishes with an outlook on the use of synchrotron radiation in molecular biology. (21 refs).

  6. Ionizing radiation

    International Nuclear Information System (INIS)

    Passchier, W.F.

    1988-01-01

    This report is part two from the series 'Future explorations' of the Dutch Counsil for Public Health. It contains contributions on biological effects of radiation in which information is presented on research into the occurrence of cancer in patients treated with radiotherapy and irradiated laboratory animals, on the effects of prenatal irradiation, and on the possibile, only in laboratory-animal research demonstrated, effects of irradiation in offspring of irradiated parents. In other contributions, which put the 'link' between the radiology and the practical radiation hygienics, it appears that the increased scientific knowledge does not make it easier to design radiation-hygienic standards and rules. (H.W.). refs.; figs.; tabs

  7. Radiation safety

    International Nuclear Information System (INIS)

    1996-04-01

    Most of the ionizing radiation that people are exposed to in day-to-day activities comes from natural, rather than manmade, sources. The health effects of radiation - both natural and artificial - are relatively well understood and can be effectively minimized through careful safety measures and practices. The IAEA, together with other international and expert organizations, is helping to promote and institute Basic Safety Standards on an international basis to ensure that radiation sources and radioactive materials are managed for both maximum safety and human benefit

  8. Radiation treatment and radiation reactions in dermatology. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Panizzon, Renato G. [Univ. Hospital CHUV, Lausanne (Switzerland). Dept. of Dermatology; Seegenschmiedt, M. Heinrich (ed.) [Strahlenzentrum Hamburg (Germany)

    2015-03-01

    Explains the use of radiation treatment in the full range of skin cancers and precancerous lesions. Covers physical and radiobiological principles, dose definitions, radiation reactions, and risk assessments. Revised and updated edition that includes new chapters and numerous additional figures. In this book, leading experts in the dermatological and oncological field describe the use of radiation therapy for the treatment of the full range of dermatological malignancies - including basal cell carcinoma, squamous cell carcinoma, cutaneous lymphomas, Kaposi's sarcoma, melanoma, and Merkel cell tumor - as well as those precancerous lesions and non-malignant dermatological disorders which are amenable to radiation therapy. In each case the specific indications for the use of radiotherapy and its application are clearly explained with the aid of numerous high-quality illustrations. In addition, the book provides a concise introduction to physical and radiobiological principles, selection of radiation factors, dose definitions, radiation reactions, and risk assessments. The new edition has been thoroughly revised and updated to reflect advances in practical knowledge and clinical practice. It will be an invaluable source of information on the management of skin tumors and related non-malignant disorders for both dermatologists, oncologists and radiation oncologists.

  9. Radiation treatment and radiation reactions in dermatology. 2. ed.

    International Nuclear Information System (INIS)

    Panizzon, Renato G.

    2015-01-01

    Explains the use of radiation treatment in the full range of skin cancers and precancerous lesions. Covers physical and radiobiological principles, dose definitions, radiation reactions, and risk assessments. Revised and updated edition that includes new chapters and numerous additional figures. In this book, leading experts in the dermatological and oncological field describe the use of radiation therapy for the treatment of the full range of dermatological malignancies - including basal cell carcinoma, squamous cell carcinoma, cutaneous lymphomas, Kaposi's sarcoma, melanoma, and Merkel cell tumor - as well as those precancerous lesions and non-malignant dermatological disorders which are amenable to radiation therapy. In each case the specific indications for the use of radiotherapy and its application are clearly explained with the aid of numerous high-quality illustrations. In addition, the book provides a concise introduction to physical and radiobiological principles, selection of radiation factors, dose definitions, radiation reactions, and risk assessments. The new edition has been thoroughly revised and updated to reflect advances in practical knowledge and clinical practice. It will be an invaluable source of information on the management of skin tumors and related non-malignant disorders for both dermatologists, oncologists and radiation oncologists.

  10. Reflectance spectra of subarctic lichens

    International Nuclear Information System (INIS)

    Petzold, D.E.; Goward, S.N.

    1988-01-01

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the mid latitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 μm, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future. (author)

  11. Low reflectance radio frequency load

    Science.gov (United States)

    Ives, R. Lawrence; Mizuhara, Yosuke M

    2014-04-01

    A load for traveling microwave energy has an absorptive volume defined by cylindrical body enclosed by a first end cap and a second end cap. The first end cap has an aperture for the passage of an input waveguide with a rotating part that is coupled to a reflective mirror. The inner surfaces of the absorptive volume consist of a resistive material or are coated with a coating which absorbs a fraction of incident RF energy, and the remainder of the RF energy reflects. The angle of the reflector and end caps is selected such that reflected RF energy dissipates an increasing percentage of the remaining RF energy at each reflection, and the reflected RF energy which returns to the rotating mirror is directed to the back surface of the rotating reflector, and is not coupled to the input waveguide. Additionally, the reflector may have a surface which generates a more uniform power distribution function axially and laterally, to increase the power handling capability of the RF load. The input waveguide may be corrugated for HE11 mode input energy.

  12. Reflectance spectra of subarctic lichens

    Science.gov (United States)

    Petzold, Donald E.; Goward, Samuel N.

    1988-01-01

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the midlatitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 microns, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future.

  13. The new operational quantities for radiation protection

    International Nuclear Information System (INIS)

    Kellerer, A.M.

    1985-01-01

    Philosophies and quantities for radiation protection have often been subjected to changes, and some of the developments are traced which ultimately led to recent proposals by ICRU. Development in the past has largely been towards clarification and generalisation of definitions. The present changes, however, reflect a more fundamental issue, the transition from the limitation system to the assessment system in radiation protection. The index quantities were suitable tools to ascertain compliance with the limitation system of radiation protection. The new quantities proposed by ICRU are suitable estimators for effective dose equivalent, which is an essential quantity in the assessment system of radiation protection. A synopsis of the definitions is given. (author)

  14. Surface reflectance of Antarctic bryophytes and protection from UV and visible light

    International Nuclear Information System (INIS)

    Robinson, S.A.; Wasley, J.; Turnbull, J.

    2000-01-01

    Full text: As well as determining the amount of solar radiation available for photosynthesis, the surface reflectance and absorptance characteristics of plants are their first defence against damaging effects of solar radiation. The solar spectrum can be damaging to plants in many ways. At shorter wavelengths, UV-B (280-320 nm) radiation can cause lesions in nucleic acid and proteins. Excess levels of visible radiation (400-750) can cause photoinhibition whilst high absorbtance of longer wavelengths (>750) leads to increases in temperature that can be detrimental in some environments. The adaptation of surface reflectance properties of vascular plants to particular environments are well known in some ecosystems. For example in desert ecosystems pubescent leaf surfaces that increase reflectance are common and have been demonstrated to be important to protection from photoinhibition. The epidermal characteristics of some plants are also known to change in absorptance, due to the accumulation of specific compounds. For example flavonoids which are effective screens against UV-B radiation, increase upon exposure to UV-B radiation. In this study we surveyed the natural variability in surface reflectance in mosses growing in continental Antarctica. Antarctica is experiencing large increases in incident UV-B radiation due to reductions in concentrations of stratospheric ozone. Additionally over the summer months (November January), when moss is exposed to direct sunlight, levels of visible solar radiation are also high, increasing the likelihood of photoinhibitory damage in moss. Our aim in this study is to describe the natural variability in the surface reflectance characteristics of moss, such that we have a baseline with which to assess future changes in response to changes in global climate, and imposed experimental treatments, and also to develop hypotheses with respect to how mosses have adapted to the cold and arid antarctic environment. Variability in surface

  15. Audible reflection density for different late reflection criteria in rooms

    DEFF Research Database (Denmark)

    Krueger, Donata; Jeong, Cheol-Ho; Brunskog, Jonas

    2012-01-01

    For reasonably accurate but practical auralizations, some simplifications and approximations are needed. The main issue in the present investigation is that the reflection density of a room impulse response, in theory, increases so fast as a quadratic function of the elapsed time, even assuming...

  16. Assessing Reflection: Understanding Skill Development through Reflective Learning Journals

    Science.gov (United States)

    Cathro, Virginia; O'Kane, Paula; Gilbertson, Deb

    2017-01-01

    Purpose: The purpose of this paper is to suggest ways in which business educators can interact successfully with reflective learning journals (RLJs). Specifically, the research was interested in how students used RLJs and how educators assessed these RLJs. Design/methodology/approach: In total, 31 RLJs, submitted as part of an international…

  17. Reflective Drawing as a Tool for Reflection in Design Research

    Science.gov (United States)

    Calvo, Mirian

    2017-01-01

    This article explores the role of drawing as a tool for reflection. It reports on a PhD research project that aims to identify and analyse the value that co-design processes can bring to participants and their communities. The research is associated with Leapfrog, a three-year project funded by the UK Arts and Humanities Research Council (AHRC).…

  18. Methodological Reflections: Inter- ethnic Research

    DEFF Research Database (Denmark)

    Singla, Rashmi

    2010-01-01

    with both youth and the parental generation with ethnic minority background in Denmark. These reflections include implications and challenges related to researcher’s national, ethnic background and educational, professional position in encounter with   diverse ‘researched persons’ such as youth......This article reflects on the methodological and epistemological aspects of the ethical issues involved in encounters between researcher and research participants with ethnic minority background in contexts with diversity. Specific challenges involved in longitudinal research (10 - 15 years......) are also considered. The issues related to the social relevance of the research deriving from psycho political validity implying consideration of power dynamics in the personal, relational and collective domains are included. The primary basis for these reflections is a follow-up study concerning young...

  19. Monitoring leaf photosynthesis with canopy spectral reflectance in rice

    International Nuclear Information System (INIS)

    Tian, Y.; Zhu, Y.; Cao, W.

    2005-01-01

    We determined the quantitative relationships between leaf photosynthetic characteristics (LPC) and canopy spectral reflectance under different water supply and nitrogen application rates in rice plants. The responses of reflectance at red radiation (680 nm) to different water contents and N rates were parallel to those of leaf net photosynthetic rate (PN). The relationships of reflectance at 680 nm and ratio index of R(810,680) (near infrared/red) to PN of different leaf positions and layers indicated that the top two full leaves were the best positions for quantitative monitoring of PN with remote sensing technique, and the index R(810,680) was the best ratio index for evaluating LPC. Testing of the models with independent data sets indicated that R(810,680) could well estimate PN of the top two leaves and canopy leaf photosynthetic potential. Hence R(810,680) can be used to monitor LPC in rice under diverse growing conditions

  20. Research Needs: Glass Solar Reflectance and Vinyl Siding

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Robert; Curcija, Charlie; Arasteh, Dariush; Goudey, Howdy; Kohler, Christian; Selkowitz, Stephen

    2011-07-07

    The subject of glass solar reflectance and its contribution to permanent vinyl siding distortion has not been extensively studied, and some phenomena are not yet well understood. This white paper presents what is known regarding the issue and identifies where more research is needed. Three primary topics are discussed: environmental factors that control the transfer of heat to and from the siding surface; vinyl siding properties that may affect heat build-up and permanent distortion; and factors that determine the properties of reflected solar radiation from glass surfaces, including insulating window glass. Further research is needed to fully characterize the conditions associated with siding distortion, the scope of the problem, physical properties of vinyl siding, insulating window glass reflection characteristics, and possible mitigation or prevention strategies.

  1. Advanced remotely maintainable force-reflecting servomanipulator concept

    International Nuclear Information System (INIS)

    Kuban, D.P.; Martin, H.L.

    1984-01-01

    A remotely maintainable force-reflecting servomanipulator concept is being developed at the Oak Ridge National Laboratory as part of the Consolidated Fuel Reprocessing Program. This new manipulator addresses requirements of advanced nuclear fuel reprocessing with emphasis on force reflection, remote maintainability, reliability, radiation tolerance, and corrosion resistance. The advanced servomanipulator is uniquely subdivided into remotely replaceable modules which will permit in situ manipulator repair by spare module replacement. Manipulator modularization and increased reliability are accomplished through a force transmission system that uses gears and torque tubes. Digital control algorithms and mechanical precision are used to offset the increased backlash, friction, and inertia resulting from the gear drives. This results in the first remotely maintainable force-reflecting servomanipulator in the world. 10 references, 4 figures, 1 table

  2. Synchrotron Radiation

    International Nuclear Information System (INIS)

    Asfour, F.I

    2000-01-01

    Synchrotron light is produced by electron accelerators combined with storage rings. This light is generated over a wide spectral region; from infra-red (IR) through the visible and vacuum ultraviolet (VUV), and into the X-ray region. For relativistic electrons (moving nearly with the speed of light), most radiation is concentrated in a small cone with an opening angle of 1/gamma(some 0.1 to 1 milliradian),where gamma is the electron energy in units of rest energy (typically 10 3 -10 4 ). In synchrotron radiation sources (storage rings) highly relativistic electrons are stored to travel along a circular path for many hours. Radiation is caused by transverse acceleration due to magnetic forces(bending magnets). The radiation is emitted in pulses of 10-20 picosecond, separated by some 2 nanosecond or longer separation

  3. Radiating confidence

    International Nuclear Information System (INIS)

    Rush, P.

    1988-01-01

    Radiation monitoring systems for operators handling radioactive wastes are described. These include a personnel monitoring system which is suitable for small groups (ie as few as 50) of personnel. The use of microelectronics enable facilities such as automatic personal dose recording with three accumulative registers and automatic reporting of exceeded dose limits. At a controlled entrance the user is identified with a personal identification number. Exit is then also monitored. The use of pocket dosimeters increase the flexibility of this system. In another system a 'rotary man lock' only allows exit from the radiation controlled zone when satisfactory radiation checks have been made. The radiation and security checks available with this system are described. A 'sack monitor' for low level wastes contained in plastic bags is illustrated. (U.K.)

  4. Radiation damage

    CERN Document Server

    Heijne, Erik H M; CERN. Geneva

    1998-01-01

    a) Radiation damage in organic materials. This series of lectures will give an overview of radiation effects on materials and components frequently used in accelerator engineering and experiments. Basic degradation phenomena will be presented for organic materials with comprehensive damage threshold doses for commonly used rubbers, thermoplastics, thermosets and composite materials. Some indications will be given for glass, scintillators and optical fibres. b) Radiation effects in semiconductor materials and devices. The major part of the time will be devoted to treat radiation effects in semiconductor sensors and the associated electronics, in particular displacement damage, interface and single event phenomena. Evaluation methods and practical aspects will be shown. Strategies will be developed for the survival of the materials under the expected environmental conditions of the LHC machine and detectors. I will describe profound revolution in our understanding of black holes and their relation to quantum me...

  5. Synchrotron radiation

    International Nuclear Information System (INIS)

    Helliwell, J.R.; Walker, R.P.

    1985-01-01

    A detailed account of the research work associated with the Synchrotron Radiation Source at Daresbury Laboratory, United Kingdom, in 1984/85, is presented in the Appendix to the Laboratory's Annual Report. (U.K.)

  6. Radiation curing

    International Nuclear Information System (INIS)

    Wendrinsky, J.

    1987-04-01

    In the beginning of the seventies the two types of radiation sources applied in industrial processes, electron radiation and UV, had been given rather optimistic forecasts. While UV could succeed in the field of panel and film coating, electron radiation curing seems to gain success in quite new fields of manufacturing. The listing of the suggested applications of radiation curing and a comparison of both advantages and disadvantages of this technology are followed by a number of case studies emphasizing the features of these processes and giving some examplary calculations. The data used for the calculations should provide an easy calculation of individual manufacturing costs if special production parameters, investment or energy costs are employed. (Author)

  7. Infrared radiation

    International Nuclear Information System (INIS)

    Moss, C.E.; Ellis, R.J.; Murray, W.E.; Parr, W.H.

    1989-01-01

    All people are exposed to IR radiation from sunlight, artificial light and radiant heating. Exposures to IR are quantified by irradiance and radiant exposure to characterize biological effects on the skin and cornea. However, near-IR exposure to the retina requires knowledge of the radiance of the IR source. With most IR sources in everyday use the health risks are considered minimal; only in certain high radiant work environments are individuals exposed to excessive levels. The interaction of IR radiation with biological tissues is mainly thermal. IR radiation may augment the biological response to other agents. The major health hazards are thermal injury to the eye and skin, including corneal burns from far-IR, heat stress, and retinal and lenticular injury from near-IR radiation. 59 refs, 13 figs, 2 tabs

  8. Radiation enteritis

    Science.gov (United States)

    ... and tobacco Almost all milk products Coffee, tea, chocolate, and sodas with caffeine Foods containing whole bran ... Call your provider if you are having radiation therapy or have had it in the past and ...

  9. Pore-level determination of spectral reflection behaviors of high-porosity metal foam sheets

    Science.gov (United States)

    Li, Yang; Xia, Xin-Lin; Ai, Qing; Sun, Chuang; Tan, He-Ping

    2018-03-01

    Open cell metal foams are currently attracting attention and their radiative behaviors are of primary importance in high temperature applications. The spectral reflection behaviors of high-porosity metal foam sheets, bidirectional reflectance distribution function (BRDF) and directional-hemispherical reflectivity were numerically investigated. A set of realistic nickel foams with porosity from 0.87 to 0.97 and pore density from 10 to 40 pores per inch were tomographied to obtain their 3-D digital cell network. A Monte Carlo ray-tracing method was employed in order to compute the pore-level radiative transfer inside the network within the limit of geometrical optics. The apparent reflection behaviors and their dependency on the textural parameters and strut optical properties were comprehensively computed and analysed. The results show a backward scattering of the reflected energy at the foam sheet surface. Except in the cases of large incident angles, an energy peak is located almost along the incident direction and increases with increasing incident angles. Through an analytical relation established, the directional-hemispherical reflectivity can be related directly to the porosity of the foam sheet and to the complex refractive index of the solid phase as well as the specularity parameter which characterizes the local reflection model. The computations show that a linear decrease in normal-hemispherical reflectivity occurs with increasing porosity. The rate of this decrease is directly proportional to the strut normal reflectivity. In addition, the hemispherical reflectivity increases as a power function of the incident angle cosine.

  10. Synchrotron radiation

    International Nuclear Information System (INIS)

    Poole, M.W.; Lea, K.R.

    1982-01-01

    A report is given on the work involving the Synchrotron Radiation Division of the Daresbury Laboratory during the period January 1981 - March 1982. Development of the source, beamlines and experimental stations is described. Progress reports from individual investigators are presented which reveal the general diversity and interdisciplinary nature of the research which benefits from access to synchrotron radiation and the associated facilities. Information is given on the organisation of the Division and publications written by the staff are listed. (U.K.)

  11. Radiation safety

    International Nuclear Information System (INIS)

    Goetz, B.B.; Murphy, C.H.

    1987-01-01

    In medicine, as in other fields of scientific endeavor, the development of advanced and specialized techniques has resulted in increased hazards for employees. However, by possessing both an appreciation of the proper use of factors that regulate radiation exposure around radiology equipment and a knowledge of the biologic effects of radiation, which can include possible genetic and somatic consequences, it is possible to maximize the usefulness of these valuable procedures while minimizing the risk to medical personnel involved with patient care

  12. Radiation shielding

    International Nuclear Information System (INIS)

    Yue, D.D.

    1979-01-01

    Details are given of a cylindrical electric penetration assembly for carrying instrumentation leads, used in monitoring the performance of a nuclear reactor, through the containment wall of the reactor. Effective yet economical shielding protection against both fast neutron and high-energy gamma radiation is provided. Adequate spacing within the assembly allows excessive heat to be efficiently dissipated and means of monitoring all potential radiation and gas leakage paths are provided. (UK)

  13. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1976-01-01

    The lecture is divided into five sections. The introduction deals with the physical and radiological terms, quantities and units. Then the basic principles of radiological protection are discussed. In the third section attention is paid to the biological effects of ionizing radiation. The fourth section deals with the objectives of practical radiological protection. Finally the emergency measures are discussed to be taken in radiation accidents. (HP) [de

  14. Synchrotron radiation

    International Nuclear Information System (INIS)

    Norman, D.; Walker, R.P.; Durham, P.J.; Ridley, P.A.

    1986-01-01

    The paper on synchrotron radiation is the appendix to the Daresbury (United Kingdom) annual report, 1985/86. The bulk of the volume is made up of the progress reports for the work carried out during the year under review using the Synchrotron Radiation Source (SRS) at Daresbury. The Appendix also contains: the scientific programmes at the the SRS, progress on beamlines, instrumentation and computing developments, and activities connected with accelerator development. (U.K.)

  15. Radiation Transport

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  16. Reflecting variable opening insulating panel

    International Nuclear Information System (INIS)

    Nungesser, W.T.

    1976-01-01

    A description is given of a reflecting variable opening insulating panel assembly, comprising a static panel assembly of reflecting insulation sheets forming a cavity along one side of the panel and a movable panel opening out by sliding from the cavity of the static panel, and a locking device for holding the movable panel in a position extending from the cavity of the static panel. This can apply to a nuclear reactor of which the base might require maintenance and periodical checking and for which it is desirable to have available certain processes for the partial dismantling of the insulation [fr

  17. Guide on reflectivity data analysis

    International Nuclear Information System (INIS)

    Lee, Jeong Soo; Ku, Ja Seung; Seong, Baek Seok; Lee, Chang Hee; Hong, Kwang Pyo; Choi, Byung Hoon

    2004-09-01

    This report contains reduction and fitting process of neutron reflectivity data by REFLRED and REFLFIT in NIST. Because the detail of data reduction like BKG, footprint and data normalization was described, it will be useful to the user who has no experience in this field. Also, reflectivity and BKG of d-PS thin film were measured by HANARO neutron reflectometer. From these, the structure of d-PS thin film was analyzed with REFLRED and REFLFIT. Because the structure of thin film such as thickness, roughness and SLD was attained in the work, the possibility of data analysis with REFLRED and REFLFIT was certified

  18. Radiation myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Howell, D A [Derbyshire Royal Infirmary, Derby (UK)

    1979-10-01

    Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed.

  19. Radiation myelopathy

    International Nuclear Information System (INIS)

    Howell, D.A.

    1979-01-01

    Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed. (UK)

  20. Radiation injuries/ionizing radiation

    International Nuclear Information System (INIS)

    Gooden, D.S.

    1991-01-01

    This book was written to aid trial attorneys involved in radiation litigation. Radiologists and medical physicists will also find it helpful as they prepare for trial, either as a litigant or an expert witness. Two chapters present checklists to guide attorneys for both plaintiffs and defendants. Gooden titles these checklists Elements of Damages and Elements of Proof and leads the reader to conclusions about each of these. One section that will be particularly helpful to attorneys contains sample interrogatories associated with a case of alleged radiation exposure resulting in a late radiation injury. There are interrogatories for the plaintiff to ask the defendant and for the defendant to ask the plaintiff