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Sample records for hto br i

  1. Energikravene i BR15

    DEFF Research Database (Denmark)

    Kragh, Jesper; Aggerholm, Søren

    2015-01-01

    Bygningsreglement 2015 – BR15 – gælder fra 1. januar 2016 med en overgangsfase frem til 1. juli 2016. Det bygger videre på BR10 og de tidligere udmeldte krav til nybyggeriet frem mod 2020. I denne kvikguide får du hurtigt overblik over, hvordan du sikrer, at de bygninger, du er med til at opføre...... eller renovere, lever op til BR15’s energikrav. Disse krav findes primært i reglementets kapitel 7 om energiforbrug og i kapitel 8 om installationer samt i kapitel 6 om indeklima....

  2. Atmospheric HT and HTO: I. Experimental procedures and tropospheric data 1968–72

    OpenAIRE

    Östlund, H. G.; Mason, A. S.

    2011-01-01

    A technique was developed for direct field sampling of atmospheric HTO and HT. Airborne, portable, and laboratory versions were implemented, and a comprehensive sampling program begun. The air is passed first through Molecular Sieve to adsorb the water, then over palladium carried on Molecular Sieve, which oxidizes atmospheric hydrogen and adsorbs the resulting water in situ. Both samples are subsequently extracted from the adsorbers, and the tritium content measured by internal low-level gas...

  3. Diffusion of HTO, {sup 36}Cl{sup -}, {sup 125}I{sup -} and {sup 22}Na{sup +} in Opalinus Clay: Effect of Confining Pressure, Sample Orientation, Sample Depth and Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Van Loon, L.R.; Soler, J.M

    2004-02-01

    Effective diffusion coefficients (D{sub e}), rock capacity factors ({alpha}) and diffusion-accessible porosities ({epsilon}) were measured using the through-diffusion technique. Transport (diffusion) was measured both perpendicular and parallel to the bedding. Special cells that allowed the application of an axial confining pressure were designed. The pressures applied ranged from 1 to 5 MPa for Mont Terri samples and between 4 and 15 MPa for Benken samples, the upper values representing the in-situ confining pressure at both locations. The test solutions used in the experiments were synthetic Opalinus Clay pore water, which has Na and Cl as main components (Mont Terri: I = 0.39 M; Benken: I = 0.20 M). Pressure only had a small effect on the value of the effective diffusion coefficients. In the case of Mont Terri samples, increasing the pressure from 1 to 5 MPa resulted in a decrease of the effective diffusion coefficient of 20% for HTO, 27% for {sup 36}Cl{sup -}, 29% for {sup 125}I{sup -} and 17 % for {sup 22}Na{sup +}. In the case of Benken samples, increasing the pressure from 4 to 15 MPa resulted in a decrease of D{sub e} of 17% for HTO, 22% for {sup 36}Cl{sup -}, 32% for {sup 125}I{sup -} and 17 % for {sup 22}Na{sup +}. Moreover, the effective diffusion coefficients for for {sup 36}Cl{sup -}are smaller than for HTO, which is consistent with an effect arising from anion exclusion. This ion exclusion effect is smaller in samples from Mont Terri than in samples from Benken, which can be explained by the higher ionic strength of the Mont Terri water used in the experiments. The diffusion of {sup 22}Na{sup +} is similar to that of HTO in the case of Mont Terri OPA. For Benken OPA, the D{sub e} value of {sup 22}Na{sup +} is a factor of 2 higher than that of HTO. This last observation cannot be explained so far but is comparable to experimental data from ANDRA (1999) on Callovo-Oxfordian claystones from the Meuse/Haute Same site. {sup 125}I{sup -} is retarded with

  4. Computer simulation of the structure of liquid metal halides RbBr, CuCl, CuBr, CuI, and AgBr

    International Nuclear Information System (INIS)

    Belashchenko, D.K.; Ostrovskij, O.I.

    2003-01-01

    The computerized models of the RbBr, AgBr, CuCl, CuBr and CuI liquid ion systems of 498 ions dimension are simulated at the temperatures of 753-960 K on the basis of the known diffraction data through the BELION algorithm. Good agreement of diffraction and model partial pair correlation functions (PPCF), excluding the PPCF first peaks heights, is obtained in all the cases. The simulation is carried out by the varied ion charges (the atomization energy values, close to the real ones, are obtained by ion charges ±1.00 for the RbBr, ±1.15 for AgBr, ±1.20 for CuCl, ±1.48 for CuBr and ±1.367 for CuI). The noncoulomb contributions in the interparticle potentials are calculated [ru

  5. Imaging the Dynamics of CH2BrI Photodissociation in the Near Ultraviolet Region.

    Science.gov (United States)

    Pan, Changen; Zhang, Yi; Lee, Joseph D; Kidwell, Nathanael M

    2018-04-19

    The photodissociation dynamics of jet-cooled CH 2 BrI were investigated in the near-ultraviolet (UV) region from 280-310 nm using velocity map imaging. We report the translational and internal energy distributions of the CH 2 Br radical and ground state I ( 2 P 3/2 ) or spin-orbit excited I ( 2 P 1/2 ) fragments determined by velocity map imaging of the ionized iodine fragments following 2 + 1 resonance-enhanced multiphoton ionization of the nascent neutral iodine products. The velocity distributions indicate that most of the available energy is partitioned into the internal energy of the CH 2 Br radical with only modest translational excitation imparted to the cofragments, which is consistent with a simple impulsive model. Furthermore, from extrapolation of the velocity distribution results, the first determination of the C-I bond dissociation energy of CH 2 BrI is presented in this work to be D 0 = 16 790 ± 590 cm -1 . The ion images appear anisotropic, indicative of a prompt dissociation, and the derived anisotropy parameters are consistently positive. Additionally, the angular distributions report on the electronic excited state dynamics, which validate recent works characterizing the electronic states responsible for the first absorption band of CH 2 BrI. In the current work, photolysis of CH 2 BrI on the red edge of the absorption spectrum reveals an additional channel producing I ( 2 P 3/2 ) fragments.

  6. Improved ETMOD modules for HTO exchange, HT deposition, and vegetation HTO

    International Nuclear Information System (INIS)

    Ogram, G.L.

    1991-01-01

    Ontario Hydro's environmental tritium model, ETMOD, calculates the potential radiological impact of short duration releases of HT and HTO. This report develops and document improved modules for the following key parameters: the deposition velocity of HT to soil, the exchange velocities of HTO to soil and vegetation, and the atmospheric stability class. These new modules allow the HT deposition velocity and the HTO exchange velocities to be estimated from readily available information (e.g. soil and weather conditions), ensure that these parameters are consistent with stability class and other model input (e.g. wind speed, season, and time of day), allow diurnal and seasonal effects to be modelled, and reduce the need for site-specific input. In addition, a module to calculated HTO concentrations in vegetation is provided that will allow the calculation of potential ingestion dose. (Author)

  7. What dictates which ion, I- or Br-, mediates the growth of cubic Pd nanocrystals?

    Science.gov (United States)

    Wang, Ze-Hong; Wu, Ya-Jiao; Xue, Huan-Huan; Zhou, Lin-Nan; Geng, Wen-Chao; Yi, Hai-Bo; Li, Yong-Jun

    2018-04-25

    Cubic Pd nanocrystals (CPNCs) as one of typical nanostructures are generally fabricated using I- or Br- as capping ions. However, which ion, I- or Br-, exclusively mediates the growth of CPNCs in a given reaction system is not well understood. Herein, regardless of I- or Br- as the capping ion, we successfully achieved CPNCs in the same reaction system simply by adjusting the pH. Based on the Finke-Watzky kinetic model, an increase in pH accelerates the overall reduction rate of Pd2+, and the formation of CPNCs only occurs over the range of specific solution reduction rate constants (k1). This kinetically illuminates that the reduction rate of Pd2+ is the physicochemical parameter that determines which ion, I- or Br-, dictates the growth of CPNCs. Also, density functional theory (DFT) calculations further elucidate the dependence of the reduction rate of Pd2+ on pH and the configuration of the activated Pd2+ complex.

  8. Re-emission of HTO into the atmosphere after HT/HTO conversion in the soil

    International Nuclear Information System (INIS)

    Foerstel, H.; Lepa, K.; Trierweiler, H.

    1988-01-01

    After HT is converted to HTO by the soil, the HTO is reemitted back into the atmosphere. Since HTO is more radiotoxic by a factor of 10/sup 4/, this reemission is an important part of the radioecological pathway of HT. Laboratory studies show that the reemission rate from natural soil cores depends on the turnover in the gas space above the soil surface. Up to a wind velocity of about 4 m s/sup -1/, the portion of HTO reemitted hourly increases to about 18% of the initial amount of the reaction product. However, after the first hour, the observed reemission rate decreases quickly to about 3% h/sup -1/. Varying the humidity of an air stream fed into the reaction chamber had no influence on the reemission rate. For the Canadian release study, small soil samples were exposed to the plume and afterwards to the air. Then, at certain intervals following the release, the soil containers were sealed with gastight lids. The remnant HTO activity was then determined by azeotropic distillation. The reemission rate was about 3% h/sup -1/ during the day. During the night, no HTO loss was observed, possibly due to dew formation

  9. Bond selective photochemistry in CH2BrI through electronic excitation at 210 nm

    International Nuclear Information System (INIS)

    Butler, L.J.; Hintsa, E.J.; Lee, Y.T.

    1986-01-01

    To explore the possibility of bond selective photochemistry in an excited electronic state, we have studied the photolysis of CH 2 BrI in a molecular beam at 210 nm. Following the direct local excitation of a repulsive transition on the C--Br bond at 210 nm, the fragments were detected by time-of-flight mass spectrometry. The dominant channel was found to be C--Br fission (60%) releasing an average of 15 kcal/mol into translation with the remainder reacting to form CH 2 +IBr and CH 2 +I+Br. There was no evidence for the primary fission of the C--I bond, making this the first clear example of the selective cleavage of a stronger bond in a molecule over the weakest one

  10. Environmental HTO/HT sampler development

    International Nuclear Information System (INIS)

    Workman, W.J.G.; Brown, R.M.; Wood, M.J.

    1992-12-01

    Tests of retention by several drying agents of HTO from an air stream containing HT have been performed. Two batches of Molecular Sieve (MS) 4A retained up to 1.3% of HT passed through them in contrast to material tested in 1986, when retention was -4 . Retention of 10 -5 to 10 -6 was observed for DRIERITE (anhydrous calcium sulphate) and Silica Gel. DRIERITE is preferred over Silica Gel as a desiccant in an air sampler for environmental HTO/HT, because it is much easier to decontaminate for reuse. An improved air sampler has been designed, 2 units constructed and components procured for 3 more. The air sampler may be line or battery operated, accommodates up to four 120 g drier or oxidizer traps, and will pump up to 4 L/min for up to 24 hours on battery power. It is build into a rugged aluminum case and weighs approximately 11 kg overall, facilitating deployment in the field

  11. Precipitation scavenging of tritiated water vapour (HTO)

    International Nuclear Information System (INIS)

    Ogram, G.L.

    1985-10-01

    Precipitation scavenging (or washout) is an important mechanism for the removal of HTO from the atmosphere. Methods of parameterizing the depletion of a plume of HTO released to the atmosphere are examined. Simple approaches, commonly used for atmospheric transport modelling purposes, such as the use of a constant washout coefficient or washout ratio, or the use of parameters based on equilibrium assumptions, are often not justified. It is shown that these parameters depend strongly on ambient temperature and plume dimensions, as well as rainfall rate. An approximate expression for washout ratio, as a function of these variables, is developed, and it is shown that near equilibrium washout conditions are only expected to hold at long plume travel distances. A possible method of treating scavenging by snow is also suggested

  12. Evaluering af energiklasserne 2015 og 2020 i BR10

    DEFF Research Database (Denmark)

    Knudsen, Henrik Nellemose; Kragh, Jesper

    Denne rapport er udarbejdet for Energistyrelsen med det formål at indsamle erfaringer fra de første byggerier, der er opført efter lavenergiklasse 2015 og bygningsklasse 2020 i Bygningsreglementet 2010 med henblik på at videreudvikle klasserne i det fremtidige bygningsreglement. Erfaringerne er i...

  13. A Compact Diffusion Sampler for Environmental Applications Requiring HTO or HTO + HT Determinations

    International Nuclear Information System (INIS)

    Otlet, R.L.; Walker, A.J.; Mather, I.D.

    2005-01-01

    Passive diffusion samplers have now been in use in the UK for the measurement of tritium at environmental levels in the form of HTO and HTO + HT for more than ten years. At the outset their main purpose was to identify the direction of a possible inadvertent release of tritium into the environment. More recently, however, there has been growing interest in their use as stand-alone devices for tritium determination at environmental levels. This has necessitated a more rigorous design to reduce the 'draughts effect' in exposed locations and has also required modifications to enable the measurement of HTO + HT. The paper describes the recent design improvements and the results of validation tests carried out against dynamic, discriminating (dry-bed) samplers

  14. Neutron scattering study of MnX2 (X = Br, I)

    International Nuclear Information System (INIS)

    Sato, Taku; Kadowaki, Hiroaki.

    1993-01-01

    Successive magnetic phase transitions in MnX 2 (X = Br, I), found by bulk measurements, are studied by neutron scattering experiments. There occur two (T N1 = 2.32K, T N2 = 2.17K) and three (T N1 = 3.95K, T N2 = 3.8K, T N3 = 3.45K) phase transitions in MnBr 2 and MnI 2 , respectively. We have found that magnetic structures of the both compounds in the intermediate temperature phases (MnBr 2 : T N1 > T > T N2 ; MnI 2 : T N1 > T > T N3 ) are transverse sinusoidally-modulated structures with incommensurate wave-vectors which vary as a function of temperature. As the temperature is lowered into the lowest temperature phases, the magnetic structures change via first order transition into ↑↑↓↓ and a helical structure for MnBr 2 and MnI 2 , respectively, which were determined by previous experiments. The successive phase transitions in MnBr 2 are accounted for quantitatively using a mean field approximation of a Hamiltonian consisting of exchange interactions up to third inter- and third intra-layer neighbor sites and the dipolar interaction. (author)

  15. HTO deposition through gas exchange between soil and atmosphere

    International Nuclear Information System (INIS)

    Feinhals, J.

    1988-06-01

    Theoretical considerations show that the ratio of HTO/H 2 O molecules, i.e. the specific activity, is not the same in atmospheric humidity and moisture absorption but differs by the so-called specific activity coefficient k. On this basis a computer model (ATHOS) was developed which allowed the calculation of both the surface contamination of the soil due to the gas exchange with a contaminated atmosphere and the depth-specific distribution of the soil acitvity. On the one hand the equations base on a modified Philip-de Vries theory, and on the other hand on a large number of soil column experiments which served the examination of the influence of parameters of microclimate and soil physics on the absorption and diffusion of tritiated water vapour under simulated conditions Above all the individual capability of each soil type to absorb moisture must be taken into consideration in connection with the HTO transfer. In this context theoretical and experimental examinations were carried out indicating a practice-related possibility to determine the soil-specific absorption capability. (orig./DG) [de

  16. Measurement of HTO permeability of materials for protective appliances

    International Nuclear Information System (INIS)

    Yamamoto, H.; Tomooka, M.; Kato, S.; Murata, M.; Kinouchi, N.; Yamamoto, H.

    1992-01-01

    Tritiated water (HTO) vapor permeabilities were measured for plastic and rubber films used for protective appliances (suits, gloves, wrappings, etc.). The measurement data prove that polyehylene and butyl rubbers are materials suitable for HTO protective appliances with their lower permeability. The data also indicate that desiccating protective appliances before reuse is effective for restoring their original resistances to penetrating HTO vapor when they are repeatedly used. (author)

  17. Analysis of I-Br-Cl in single fluid inclusions by LA-ICP-MS

    Science.gov (United States)

    Giehl, C.; Fusswinkel, T.; Beermann, O.; Garbe-Schönberg, D.; Scholten, L.; Wagner, T.

    2017-12-01

    Halogens are excellent tracers of hydrothermal fluid sources and in-situ LA-ICP-MS analysis of Cl and Br in single fluid inclusions has provided fundamentally new insight into hydrothermal fluid flow and ore formation. There is mounting evidence that enrichment and depletion of Br relative to Cl may be caused by a number of processes beyond seawater evaporation and halite dissolution which cannot be discriminated on the basis of Br/Cl ratios alone. Expanding the analytical capabilities of fluid inclusion LA-ICP-MS analysis to include iodine would allow to discern between selective and coupled enrichment processes of Cl, Br and I, even in geologically complex samples that are inaccessible to bulk extraction techniques. We present iodine concentration data determined by LA-ICP-MS analysis of synthetic fluid inclusions, using the Sca17 scapolite reference material for external standardization (Seo et al., 2011). Iodine concentrations in Sca17 were determined using the Durango apatite standard. Four starting solutions containing I (0.3, 1.5, 27, 78 µg/g), Br (941, 1403, 2868, 4275 µg/g), Na (30.7, 94.7 mg/g), and Cl (50, 137 mg/g) (analyzed by ICP-OES and ICP-MS at CAU Kiel) were prepared by dissolving reagent grade chemical powders in ultra-pure water. Spherical inclusions (up to 40 µm) were synthesized from the starting solutions in pre-cracked, HF-treated synthetic quartz crystals which were placed in gold capsules and equilibrated at 600°C, 100/200 MPa in cold seal pressure vessels. Fluid inclusion LA-ICP-MS analysis (University of Helsinki) yielded average I concentrations in excellent agreement with the starting solutions (27.3 µg/g ± 14 %RSD for the 27 µg/g solution and 77.6 µg/g ± 8.3 %RSD for the 78 µg/g solution). Average Br and I concentrations deviate less than 10 % from solution concentration values. For the low I concentration solutions, the synthetic inclusions were too small to detect I. Thus, given suitable standard materials and sufficient

  18. Environmental HTO/HT sampler development

    International Nuclear Information System (INIS)

    Workman, W.J.G.; Brown, R.M.; Wood, M.J.

    1994-01-01

    Tests of retention by several drying agents of HTO from an air stream containing HT have been performed. Two batches of Molecular Sieve (MS) 4A retained up to 1.3% of HT passed through them, in contrast to material tested in 1986, when retention was -4 . Retention of 10 -5 to 10 -6 was observed for DRIERITE (anhydrous calcium sulphate) and Silica Gel. DRIERITE is preferred over Silica Gel as a desiccant in an air sampler for environmental HTO/HT, because it is much easier to decontaminate for reuse. An improved air sampler has been designed, 2 units constructed and components procured for 3 more. The air sampler may be line or battery operated, accommodates up to four 120 g drier or oxidizer traps, and will pump up to 4 L/min for up to 24 hours on battery power. It is built into a rugged aluminum case and weighs approximately 11 kg overall, facilitating deployment in the field. (author). 5 refs., 2 tabs., 4 figs

  19. Stability and Performance of CsPbI2Br Thin Films and Solar Cell Devices.

    Science.gov (United States)

    Mariotti, Silvia; Hutter, Oliver S; Phillips, Laurie J; Yates, Peter J; Kundu, Biswajit; Durose, Ken

    2018-01-31

    In this manuscript, the inorganic perovskite CsPbI 2 Br is investigated as a photovoltaic material that offers higher stability than the organic-inorganic hybrid perovskite materials. It is demonstrated that CsPbI 2 Br does not irreversibly degrade to its component salts as in the case of methylammonium lead iodide but instead is induced (by water vapor) to transform from its metastable brown cubic (1.92 eV band gap) phase to a yellow phase having a higher band gap (2.85 eV). This is easily reversed by heating to 350 °C in a dry environment. Similarly, exposure of unencapsulated photovoltaic devices to water vapor causes current (J SC ) loss as the absorber transforms to its more transparent (yellow) form, but this is also reversible by moderate heating, with over 100% recovery of the original device performance. NMR and thermal analysis show that the high band gap yellow phase does not contain detectable levels of water, implying that water induces the transformation but is not incorporated as a major component. Performances of devices with best efficiencies of 9.08% (V OC = 1.05 V, J SC = 12.7 mA cm -2 and FF = 68.4%) using a device structure comprising glass/ITO/c-TiO 2 /CsPbI 2 Br/Spiro-OMeTAD/Au are presented, and further results demonstrating the dependence of the performance on the preparation temperature of the solution processed CsPbI 2 Br films are shown. We conclude that encapsulation of CsPbI 2 Br to exclude water vapor should be sufficient to stabilize the cubic brown phase, making the material of interest for use in practical PV devices.

  20. Effects of CuBr addition to CH3NH3PbI3(Cl) perovskite photovoltaic devices

    Science.gov (United States)

    Oku, Takeo; Ohishi, Yuya; Tanaka, Hiroki

    2018-01-01

    Effects of CuBr addition to perovskite CH3NH3PbI3(Cl) precursor solutions on photovoltaic properties were investigated. The CH3NH3Pb(Cu)I3(Cl,Br)-based photovoltaic devices were fabricated by a spin-coating technique, and the microstructures of the devices were investigated by X-ray diffraction, optical microscopy and scanning electron microscopy. Current density-voltage characteristics were improved by a small amount of CuBr addition, which resulted in improvement of the conversion efficiencies of the devices. The structure analysis showed decrease of unit cell volume and increase of Cu/Br composition by the CuBr addition, which would indicate the Cu/Br substitution at the Pb/I sites in the perovskite crystal, respectively.

  1. HTO deposition by vapor exchange between atmosphere and soil

    International Nuclear Information System (INIS)

    Bunnenberg, C.

    1989-01-01

    HTO deposition to soils occurs by vapor exchange between atmosphere and soil-air, when the concentration gradient is directed downwards, and it is principally independent from simultaneous transport of H 2 O. In relatively dry top soil, which is frequently the case, as it tries to attain equilibrium with the air humidity, HTO diffuses into deeper soil driven by the same mechanisms that caused the deposition process. The resulting HTO profile is depending on the atmospheric supply and the soil physical conditions, and it is the source for further tritium pathways, namely root uptake by plants and reemission from soil back into the ground-level air. Simulation experiments with soil columns exposed to HTO labeled atmospheres have proved the theoretical expectation that under certain boundary conditions the HTO profile can be described by an error function. The key parameter is the effective diffusion coefficient, which in turn is a function of the sorption characteristics of the particular soil. (orig.) [de

  2. Global impacts of tropospheric halogens (Cl, Br, I on oxidants and composition in GEOS-Chem

    Directory of Open Access Journals (Sweden)

    T. Sherwen

    2016-09-01

    Full Text Available We present a simulation of the global present-day composition of the troposphere which includes the chemistry of halogens (Cl, Br, I. Building on previous work within the GEOS-Chem model we include emissions of inorganic iodine from the oceans, anthropogenic and biogenic sources of halogenated gases, gas phase chemistry, and a parameterised approach to heterogeneous halogen chemistry. Consistent with Schmidt et al. (2016 we do not include sea-salt debromination. Observations of halogen radicals (BrO, IO are sparse but the model has some skill in reproducing these. Modelled IO shows both high and low biases when compared to different datasets, but BrO concentrations appear to be modelled low. Comparisons to the very sparse observations dataset of reactive Cl species suggest the model represents a lower limit of the impacts of these species, likely due to underestimates in emissions and therefore burdens. Inclusion of Cl, Br, and I results in a general improvement in simulation of ozone (O3 concentrations, except in polar regions where the model now underestimates O3 concentrations. Halogen chemistry reduces the global tropospheric O3 burden by 18.6 %, with the O3 lifetime reducing from 26 to 22 days. Global mean OH concentrations of 1.28  ×  106 molecules cm−3 are 8.2 % lower than in a simulation without halogens, leading to an increase in the CH4 lifetime (10.8 % due to OH oxidation from 7.47 to 8.28 years. Oxidation of CH4 by Cl is small (∼  2 % but Cl oxidation of other VOCs (ethane, acetone, and propane can be significant (∼  15–27 %. Oxidation of VOCs by Br is smaller, representing 3.9 % of the loss of acetaldehyde and 0.9 % of the loss of formaldehyde.

  3. Inter ionic pair potentials for molten copper halides CuX (X=Br, I)

    International Nuclear Information System (INIS)

    Canan, C.

    2004-01-01

    In this work, the inter-ionic pair interactions of molten CuBr and Cu I are described with three different form of the rigid ion model potentials (RIM) using i) the functional form originally proposed by Vasishta and Rahman ii) the form used Madden and coworkers which is include the polarization contributions iii) the form parameterizied by Tatlipinar et al. The capability of these potentials have been discussed with each other by calculating the static liquid structure. We present the results of the partial pair distributions for molten CuBr at 810K and for molten Cul at 940K comparing with experimental data. The structural calculations are performed by solving the numerically the hypemetted chain approximate theory of liquids

  4. Fluorescence Blinking and Photoactivation of All-Inorganic Perovskite Nanocrystals CsPbBr3 and CsPbBr2I.

    Science.gov (United States)

    Seth, Sudipta; Mondal, Navendu; Patra, Satyajit; Samanta, Anunay

    2016-01-21

    Study of the emission behavior of all-inorganic perovskite nanocrystals CsPbBr3 and CsPbBr2I as a function of the excitation power employing fluorescence correlation spectroscopy and conventional techniques reveals fluorescence blinking in the microsecond time scale and photoinduced emission enhancement. The observation provides insight into the radiative and nonradiative deactivation pathways of these promising substances. Because both blinking and photoactivation processes are intimately linked to the charge separation efficiency and dynamics of the nanocrystals, these key findings are likely to be helpful in realizing the true potential of these substances in photovoltaic and optoelectronic applications.

  5. The neutron diffraction of molten TlCl, TlBr, and TlI

    International Nuclear Information System (INIS)

    Satow, T.; Uemura, O.; Hoshino, K.; Watanabe, T.

    1984-01-01

    Structure factors S(K) for liquid TlCl, TlBr, and TlI are determined by neutron diffraction measurements. Atomic radial distribution functions (RDF) derived from S(K) are presented. All RDF values are slightly smaller than those of their solid state counter parts. Results show that TlX has a tendency not to retain cesium-chloride type local order, but to take sodium-chloride type order when melting

  6. Ion yields of laser aligned CH3I and CH3Br from multiple orbitals

    NARCIS (Netherlands)

    He, Lanhai; Pan, Yun; Yang, Yujun; Luo, Sizuo; Lu, Chunjing; Zhao, Huifang; Li, Dongxu; Song, Lele; Stolte, Steven; Ding, Dajun; Roeterdink, Wim G.

    2016-01-01

    We have measured the alignment influence on ion yields of CH3I and CH3Br molecules in the laser intensity regime from 1013 W/cm2 to 1015 W/cm2. The hexapole state-selection technique combined with laser induced alignment has been employed to obtain aligned (〈P2(cosθ)〉=0.7) and anti-aligned

  7. $\\beta$-delayed neutrons from oriented $^{137,139}$I and $^{87,89}$Br nuclei

    CERN Multimedia

    We propose a world-first measurement of the angular distribution of $\\beta$‐delayed n and $\\gamma$-radiation from oriented $^{137, 139}$I and $^{87,89}$Br nuclei, polarised at low temperature at the NICOLE facility. $\\beta$­-delayed neutron emission is an increasingly important decay mechanism as the drip line is approached and its detailed understanding is essential to phenomena as fundamental as the r‐process and practical as the safe operation of nuclear power reactors. The experiments offer sensitive tests of theoretical input concerning the allowed and first­‐forbidden $\\beta$‐decay strength, the spin-density of neutron emitting states and the partial wave barrier penetration as a function of nuclear deformation. In $^{137}$I and $^{87}$Br the decay feeds predominantly the ground state of the daughters $^{136}$Xe and $^{86}$Kr whereas in $^{139}$I and $^{89}$Br we will explore the use of n-$\\gamma$- coincidence to study neutron transitions to the first and second excited states in the daughters...

  8. $\\beta$-delayed neutrons from oriented $^{137,139}$I and $^{87,89}$Br nuclei

    CERN Document Server

    Grzywacz, Robert; Stone, Nicholas; Köster, Ulli; Singh, Barlaj; Bingham, Carrol; Gaulard, S; Kolos, Karolina; Madurga, Miguel; Nikolov, J; Otsubo, T; Roccia, S; Veskovic, Miroslav; Walker, Phil; Walters, William

    2013-01-01

    We propose a world-­‐first measurement of the angular distribution of $\\beta$-­‐delayed n and $\\gamma$- radiation from oriented $^{137, 139}$I and $^{87,89}$Br nuclei, polarised at low temperature at the NICOLE facility. $\\beta$-­‐delayed neutron emission is an increasingly important decay mechanism as the drip line is approached and its detailed understanding is essential to phenomena as fundamental as the r‐process and practical as the safe operation of nuclear power reactors. The experiments offer sensitive tests of theoretical input concerning the allowed and first-­‐forbidden $\\beta$‐decay strength, the spin-­‐density of neutron emitting states and the partial wave barrier penetration as a function of nuclear deformation. In $^{137}$I and $^{87}$Br the decay feeds predominantly the ground state of the daughters $^{136}$Xe and $^{86}$Kr whereas in $^{139}$I and $^{89}$Br we will explore the use of n-$\\gamma$- coincidence to study neutron transitions to the first and second excited state...

  9. Photoproduction of I2, Br2, and Cl2 on n-semiconducting powder

    Science.gov (United States)

    Reichman, B.; Byvik, C. E.

    1981-01-01

    The photosynthetic production of Br2 and Cl2 and the photocatalytic production of I2 from aqueous solutions of the respective halide ions in the presence of platinized semiconducting n-TiO2 powder are reported. Reactions were produced in 2-3 M oxygen-saturated aqueous solutions of KI, KBr or NaCl containing Pt-TiO2 powder which were irradiated by a high-pressure mercury lamp at a power of 400 mW/sq cm. Halogens are found to be produced in greater quantities when platinized TiO2 powders are used rather than pure TiO2, and rates of halogen production are observed to increase from Cl2 to Br2 to I2. The presence of the synthetic reactions producing Br2 and Cl2 with a net influx of energy indicates that an effective separation of the photoproduced electron-hole pair occurs in the semiconductor. Quantum efficiencies of the reaction, which increase with decreasing solution pH, are found to be as high as 30%, implying a solar-to-chemical energy conversion efficiency between 0.03% and 3% for the case of chlorine production. It is concluded that the photoproduction of halogens may be of practical value if product halogens are efficiently removed from the reaction cell.

  10. Synthesis, Structure, and Li-Ion Conductivity of LiLa(BH4)3X, X = Cl, Br, I

    DEFF Research Database (Denmark)

    Payandeh GharibDoust, SeyedHosein; Brighi, Matteo; Sadikin, Yolanda

    2017-01-01

    In this work, a new type of addition reaction between La(BH4)3 and LiX, X = Cl, Br, I, is used to synthesize LiLa(BH4)3Cl and two new compounds LiLa(BH4)3X, X = Br, I. This method increases the amounts of LiLa(BH4)3X and the sample purity. The highest Li-ion conductivity is observed for LiLa(BH4)...

  11. Spin splitting in band structures of BiTeX (X=Cl, Br, I) monolayers

    Science.gov (United States)

    Hvazdouski, D. C.; Baranava, M. S.; Stempitsky, V. R.

    2018-04-01

    In systems with breaking of inversion symmetry a perpendicular electric field arises that interacts with the conduction electrons. It may give rise to electron state splitting even without influence of external magnetic field due to the spin-orbital interaction (SOI). Such a removal of the spin degeneracy is called the Rashba effect. Nanostructure with the Rashba effect can be part of a spin transistor. Spin degeneracy can be realized in a channel from a material of this type without additive of magnetic ions. Lack of additive increases the charge carrier mobility and reliability of the device. Ab initio simulations of BiTeX (X=Cl, Br, I) monolayers have been carried out using VASP wherein implemented DFT method. The study of this structures is of interest because such sort of structures can be used their as spin-orbitronics materials. The crystal parameters of BiTeCl, BiTeBr, BiTeI have been determined by the ionic relaxation and static calculations. It is necessary to note that splitting of energy bands occurs in case of SOI included. The values of the Rashba coefficient aR (in the range from 6.25 to 10.00 eV·Å) have high magnitudes for spintronics materials. Band structure of monolayers structures have ideal Rashba electron gas, i.e. there no other energy states near to Fermi level except Rashba states.

  12. Quantum state-to-state dynamics for the quenching process of Br(2P1/2) + H2(v(i) = 0, 1, j(i) = 0).

    Science.gov (United States)

    Xie, Changjian; Jiang, Bin; Xie, Daiqian; Sun, Zhigang

    2012-03-21

    Quantum state-to-state dynamics for the quenching process Br((2)P(1/2)) + H(2)(v(i) = 0, 1, j(i) = 0) → Br((2)P(3/2)) + H(2)(v(f), j(f)) has been studied based on two-state model on the recent coupled potential energy surfaces. It was found that the quenching probabilities have some oscillatory structures due to the interference of reflected flux in the Br((2)P(1/2)) + H(2) and Br((2)P(3/2)) + H(2) channels by repulsive potential in the near-resonant electronic-to-vibrational energy transfer process. The final vibrational state resolved integral cross sections were found to be dominated by the quenching process Br((2)P(1/2)) + H(2)(v) → Br((2)P(3/2)) + H(2)(v+1) and the nonadiabatic reaction probabilities for Br((2)P(1/2)) + H(2)(v = 0, 1, j(i) = 0) are quite small, which are consistent with previous theoretical and experimental results. Our calculated total quenching rate constant for Br((2)P(1/2)) + H(2)(v(i) = 0, j(i) = 0) at room temperature is in good agreement with the available experimental data. © 2012 American Institute of Physics

  13. Positron emission intensities in the decay of 64Cu, 76Br and 124I

    International Nuclear Information System (INIS)

    Qaim, S.M.; Bisinger, T.; Hilgers, K.; Nayak, D.; Coenen, H.H.

    2007-01-01

    The relatively long-lived positron emitters 64 Cu (t 1/2 = 12.7 h), 76 Br (t 1/2 = 16.2 h) and 124 I (t 1/2 = 4.18 d) are finding increasing applications in positron emission tomography (PET). For precise determination of their positron emission intensities, each radionuclide was prepared via a charged particle induced reaction in a ''no-carrier-added'' form and with high radionuclidic purity. It was then subjected to γ-ray and X-ray spectroscopy as well as to anticoincidence beta and γγ-coincidence counting. The positron emission intensities measured were: 64 Cu (17.8 ± 0.4)%, 76 Br (58.2 ± 1.9)% and 124 I (22.0 ± 0.5)%. The intensity of the weak 1346 keV γ-ray emitted in the decay of 64 Cu was determined as (0.54 ± 0.03)%. Some implications of the precisely determined nuclear data are discussed. (orig.)

  14. Theoretical study of X⁻ · 1 · YF (1 = triazine, X = Cl, Br and I, Y = H, Cl, Br, I, PH₂ and AsH₂): noncovalently electron-withdrawing effects on anion-arene interactions.

    Science.gov (United States)

    Chen, Yishan; Yao, Lifeng

    2014-01-01

    The ternary complexes X(-) · 1 · YF (1 = triazine, X = Cl, Br and I, Y = H, Cl, Br, I, PH2 and AsH2) have been investigated by MP2 calculations to understand the noncovalently electron-withdrawing effects on anion-arene interactions. The results indicate that in binary complexes (1 · X(-)), both weak σ-type and anion-π complexes can be formed for Cl(-) and Br(-), but only anion-π complex can be formed for I(-). Moreover, the hydrogen-bonding complex is the global minimum for all three halides in binary complexes. However, in ternary complexes, anion-π complex become unstable and only σ complex can retain in many cases for Cl(-) and Br(-). Anion-π complex keeps stable only when YF = HF. In contrast with binary complexes, σ complex become the global minimum for Cl(-) and Br(-) in ternary complexes. These changes in binding mode and strength are consistent with the results of covalently electron-withdrawing effects. However, in contrast with the covalently electron-withdrawing substituents, Cl(-) and Br(-) can attack the aromatic carbon atom to form a strong σ complex when the noncovalently electron-withdrawing effect is induced by halogen bonding. The binding behavior for I(-) is different from that for Cl(-) and Br(-) in two aspects. First, the anion-π complex for I(-) can also keep stable when the noncovalent interaction is halogen bonding. Second, the anion-π complex for I(-) is the global minimum when it can retain as a stable structure.

  15. Formability of ABX3 (X=F,Cl,Br,I) halide perovskites

    International Nuclear Information System (INIS)

    Li Chonghea; Lu Xionggang; Ding Weizhong; Feng Liming; Gao Yonghui; Guo Ziming

    2008-01-01

    In this study a total of 186 complex halide systems were collected; the formabilities of ABX 3 (X = F, Cl, Br and I) halide perovskites were investigated using the empirical structure map, which was constructed by Goldschmidt's tolerance factor and the octahedral factor. A model for halide perovskite formability was built up. In this model obtained, for all 186 complex halides systems, only one system (CsF-MnF 2 ) without perovskite structure and six systems (RbF-PbF 2 , CsF- BeF 2 , KCl-FeCl 2 , TlI-MnI 2 , RbI-SnI 2 , TlI-PbI 2 ) with perovskite structure were wrongly classified, so its predicting accuracy reaches 96%. It is also indicated that both the tolerance factor and the octahedral factor are a necessary but not sufficient condition for ABX 3 halide perovskite formability, and a lowest limit of the octahedral factor exists for halide perovskite formation. This result is consistent with our previous report for ABO 3 oxide perovskite, and may be helpful to design novel halide materials with the perovskite structure. (orig.)

  16. Radiation processes in organic halides (Cl, Br, I) studied by ESR spectroscopy

    International Nuclear Information System (INIS)

    Symons, M.C.R.

    1980-01-01

    Electron-loss from alkyl halides (Cl, Br, I) gives Rhal. + which may dimerise to give (Rhal-halR) + σ* radicals with characteristic ESR spectra, or may lose H + to give α-halo radicals (R 2 Chal) also with well characterised ESR spectra. Electron-capture gives dissociation, but there may be weak residual charge-transfer interaction between R. and hal - which gives rise to well defined hyperfine coupling from the halide nuclei. Loss of β-hydrogen gives β-halo radicals, R 2 C-CH 2 hal (Cl,Br) whose conformation, established by ESR spectroscopy, is such that the halogen atom lies out of the radical plane so that overlap between the half-filled 2p(π) orbital and the C-hal (σ) orbital is maximised. Electron addition to α-halocarboxylates and related compounds probably gives β-halo radical anions, (R 2 C[hal]CO 2 H) - with a similar preferred conformation. Alternative structures are considered for these species. (author)

  17. Diffusion of tritiated water (HTO) in dextran+water mixtures

    International Nuclear Information System (INIS)

    Comper, W.D.; Van Damme, M.P.I.; Preston, B.N.

    1982-01-01

    The diffusion of HTO has been measured in dextran solutions using an open-ended capillary technique and a newly developed Sundeloef diffusion cell. HTO diffusion has been examined as a function of dextran concentration and molecular weight. These results, together with our previous results on the intradiffusion and mutual-diffusion coefficients of dextrans, now provide a complete set of conventional translational diffusion coefficients for both components in this binary system. Various assumptions associated with the theoretical description of polymer translational motion can now be examined. (author)

  18. Chemical vapour transport of pyrite (FeS 2) with halogen (Cl, Br, I)

    Science.gov (United States)

    Fiechter, S.; Mai, J.; Ennaoui, A.; Szacki, W.

    1986-12-01

    A systematic study of chemical vapour transport (CVT) of pyrite with halogen, hydrogen halides and ammonium halides as transporting agents has shown that the transport with chlorine and bromine in a temperature gradient Δ T = 920-820 K yields the highest transport rates (˜6 mg/h) with crystals up to 5 mm edge length. Computing thermochemical equilibria and flux functions in the system Fe-S-Hal (Hal = Cl, Br, I) it has been confirmed that the transport velocity of pyrite is limited by the concentration of FeHal 2 in the vapour phase, the equilibrium position between FeHal 2(g) and FeHal 3(g) and the flux directions of the iron gas species.

  19. Use of 82Br and 131I radionuclides in studies of goitrogenic effects of exogenous bromide

    International Nuclear Information System (INIS)

    Stanislav Pavelka

    2012-01-01

    The interference of excessive bromide intake with iodine metabolism in the rat was studied using 82 Br and 131 I radionuclides. Mainly lactating rat dams and their pups were used, in addition to adult male rats, in the present studies. Particularly, the influence of high bromide intake in lactating rat dams on the transfer of iodine and bromide to suckling young through breast milk was evaluated. The induction of hypothyroid status in the pups by high bromide intake in the mothers was proved unambiguously. Excessive bromide in lactating rat dams caused a marked decrease in plasma levels of thyroid hormones both, in the mothers and in their sucklings. The effects of an enhanced bromide intake on the thyroid function in relation to iodine status in the animals were also followed. Marked goitrogenic and thyrotoxic effects of excessive bromide in adult rats were significantly enhanced under the conditions of simultaneous iodine deficiency in the experimental animals. (author)

  20. Superconducting nitride halides MNX (M = Ti, Zr, Hf; X = Cl, Br, I)

    Energy Technology Data Exchange (ETDEWEB)

    Schurz, Christian M.; Shlyk, Larysa; Schleid, Thomas; Niewa, Rainer [Stuttgart Univ. (Germany). Inst. fuer Anorganische Chemie

    2011-07-01

    Two different polymorphs of the metal nitride halides MNX (M = Ti, Zr, Hf; X = Cl, Br, I) are known to crystallize in layered structures. The two crystal structures differ in the way {sub {infinity}}{sup 2}{l_brace}X[M{sub 2}N{sub 2}]X{r_brace} slabs are stacked along the c-axes. Metal atoms and/or organic molecules can be intercalated into the van-der-Waals gap between these layers. After such an electron-doping via intercalation the prototypic band insulators change into superconductors with moderate high critical temperatures T{sub c} up to 25.5 K. This review gathers information on synthesis routes, structural characteristics and properties of the prototypic nitride halides and the derivatives after electron-doping with a focus on superconductivity. (orig.)

  1. Electrochemical Behavior of LiBr, LiI, and Li2Se in LiCl Molten Salt

    International Nuclear Information System (INIS)

    Choi, In Kyu; Do, Jae Bum; Hong, Sun Seok; Seo, Chung Seok

    2006-03-01

    The effect of fission products on the electrolytic reduction of uranium oxide has been studied. It has been reported that volatile fission products, such as Br, I, and Se, react with Li metal which is a reductant in the process to give LiBr, LiI, and Li 2 Se. These compounds are dissociated as corresponding anions and cations in the LiCl molten salt at 650 .deg. C. In this experiment, oxidation and reduction reaction of 3wt% of each compound in LiCl molten salt were investigated by cyclic voltammetry. For LiBr, redox reactions of cation and anion were reversible, while redox reactions of Li + and I - were irreversible. For Li 2 Se, about half of the produced Li metal was disappeared at the cathode and two anodic current curves were appeared. After the cyclic voltammetric measurements for each compound, chronopotentiometric experiment was carried out for one hour with 100 - 400 mA. After the electrolysis, no compounds gave Li metal in the porous MgO filter in which Li metal was produced at the cathode. However, LiCl salt was covered with Br 2 for LiBr electrolysis. Dark red color of Br 2 was easily removed by water. For LiI electrolysis, salt gave black color and I 2 was deposited on the Pt anode. For Li 2 Se electrolysis, black fine powders were precipitated in the salt. After the separation and dryness of the precipitates, it was analyzed with XRD and it turned out PtSe 2 . From the electrochemical experimental results, it was concluded that these compounds may affect the electrolytic reduction process of uranium oxide in the spent fuel

  2. Haloacyl complexes of boron, [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I).

    Science.gov (United States)

    Finze, Maik; Bernhardt, Eduard; Willner, Helge; Lehmann, Christian W

    2005-11-04

    The haloacyltris(trifluoromethyl)borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been synthesized by reacting (CF3)3BCO with either MHal (M=K, Cs; Hal=F) in SO2 or MHal (M=[nBu4N]+, [Et4N]+, [Ph4P]+; Hal=Cl, Br, I) in dichloromethane. Metathesis reactions of the fluoroacyl complex with Me3SiHal (Hal=Cl, Br, I) led to the formation of its higher homologues. The thermal stabilities of the haloacyltris(trifluoromethyl)borates decrease from the fluorine to the iodine derivative. The chemical reactivities decrease in the same order as demonstrated by a series of selected reactions. The new [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br) salts are used as starting materials in the syntheses of novel compounds that contain the (CF3)3B-C fragment. All borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been characterized by multinuclear NMR spectroscopy (11B, 13C, 17O, 19F) and vibrational spectroscopy. [PPh4][(CF3)3BC(O)Br] crystallizes in the monoclinic space group P2/c (no. 13) and the bond parameters are compared with those of (CF3)3BCO and K[(CF3)3BC(O)F]. The interpretation of the spectroscopic and structural data are supported by DFT calculations [B3LYP/6-311+G(d)].

  3. New results on two synthetic conductors (TMTSF)2BrO4 and (BEDT-TTF)2I3

    DEFF Research Database (Denmark)

    Mortensen, Kell; Jacobsen, C. S.; Bechgaard, K.

    1985-01-01

    The authors present experimental studies of transport properties of (TMTSF)2BrO4 and (BEDT-TTF)2I3 . The behaviour of the TMTSF salt suggests transport via variable-range hopping among localized states. The BEDT-TTF-salt exhibits thermopower which indicates almost isotropic metallic behaviour in ...

  4. Modulation of electronic and optical properties in mixed halide perovskites CsPbCl3xBr3(1-x) and CsPbBr3xI3(1-x)

    Science.gov (United States)

    Zhou, Ziqi; Cui, Yu; Deng, Hui-Xiong; Huang, Le; Wei, Zhongming; Li, Jingbo

    2017-03-01

    The recent discovery of lead halide perovskites with band gaps in the visible presents important potential in the design of high efficient solar cells. CsPbCl3, CsPbBr3 and CsPbI3 are stable compounds within this new family of semiconductors. By performing the first-principles calculation, we explore the structural, electronic and optical properties of CsPbCl3xBr3(1-x) and CsPbBr3xI3(1-x) with various compositions of halide atoms. Structural stability is demonstrated with halide atoms distributing randomly at the halide atomic sites. CsPbCl3xBr3(1-x) and CsPbBr3xI3(1-x) exhibit the modulation of their band gaps by varying the halide composition. Our results also indicate that CsPbCl3xBr3(1-x) and CsPbBr3xI3(1-x) with different halide compositions are suitable to application to solar cells for the general features are well preserved. Good absorption to lights of different wavelengths has been obtained in these mixed halide perovskites.

  5. Synthesis and characterizations of spherical hollow composed of AgI nanoparticle using AgBr as the precursor

    International Nuclear Information System (INIS)

    Yang Ming; Zhou Kui

    2011-01-01

    Hollow spheres of AgI with an average radius of 100-200 nm have been prepared by a simple reaction between AgBr suspension and KI in the presence of gelatin. Gelatin played a decisive role as an inhibitor of the direct attack of I - ions to AgBr surfaces and coagulation of the growing AgI in producing the spherical AgI particles. The products were characterized by X-ray powder diffraction, transmission electron microscopy, UV-vis absorption spectroscopy and X-ray photoelectron spectra techniques. The band gaps are estimated to be 2.95 eV according to the results of optical measurements of the hollow spheres of AgI.

  6. Structural and electronic properties of silicene on MgX2 (X = Cl, Br, and I)

    KAUST Repository

    Zhu, Jiajie

    2014-07-23

    Silicene is a monolayer of Si atoms in a two-dimensional honeycomb lattice, being expected to be compatible with current Si-based nanoelectronics. The behavior of silicene is strongly influenced by the substrate. In this context, its structural and electronic properties on MgX2 (X = Cl, Br, and I) have been investigated using first-principles calculations. Different locations of the Si atoms are found to be energetically degenerate because of the weak van der Waals interaction with the substrates. The Si buckling height is below 0.55 Å, which is close to the value of free-standing silicene (0.49 Å). Importantly, the Dirac cone of silicene is well preserved on MgX2 (located slightly above the Fermi level), and the band gaps induced by the substrate are less than 0.1 eV. Application of an external electric field and stacking can be used to increase the band gap. © 2014 American Chemical Society.

  7. Differential measurement of low level HTO and HT leak rates

    International Nuclear Information System (INIS)

    Sheehan, W.E.; Muldoon, K.M.

    1976-08-01

    Leak rates of 5 x 10 -17 cm 3 /sec and greater can be measured by a very simple technique that will also differentiate tritium oxide (HTO) from tritium gas (HT). Because of the much greater health hazard of tritium oxide (200 to 1), the determination of chemical form is significant. The method involves flushing a gas collection chamber, containing the item being measured, with dry air. The flushed air is passed through an ethylene glycol bubbler which removes only the HTO. The outlet of the ethylene glycol bubbler is connected to a heated (400 0 C) palladium sponge catalyst which converts the HT to HTO and then to a second ethylene glycol bubbler for collection of the oxidized tritium gas. Liquid scintillation (p-dioxane base) counting solution is added directly to the bubblers and counted for tritium in a Liquid Scintillation Spectrometer. Advantages, method validation, operational experience, and data obtained by this technique are discussed. The sensitivity of the method is dependent on the time allowed between bubbler changes, the liquid scintillation spectrometer counting efficiency, background, and counting times employed

  8. Intercomparison of model predictions of tritium concentrations in soil and foods following acute airborne HTO exposure

    International Nuclear Information System (INIS)

    Barry, P.J.; Watkins, B.M.; Belot, Y.; Davis, P.A.; Edlund, O.; Galeriu, D.; Raskob, W.; Russell, S.; Togawa, O.

    1998-01-01

    This paper describes the results of a model intercomparision exercise for predicting tritium transport through foodchains. Modellers were asked to assume that farmland was exposed for one hour to an average concentration in air of 10 4 MBq tritium m -3 . They were given the initial soil moisture content and 30 days of hourly averaged historical weather and asked to predict HTO and OBT concentrations in foods at selected times up to 30 days later when crops were assumed to be harvested. Two fumigations were postulated, one at 10.00 h (i.e., in day-light), and the other at 24.00 h (i.e., in darkness).Predicted environmental media concentrations after the daytime exposure agreed within an order of magnitude in most cases. Important sources of differences were variations in choices of numerical values for transport parameters. The different depths of soil layers used in the models appeared to make important contributions to differences in predictions for the given scenario. Following the night-time exposure, however, greater differences in predicted concentrations appeared. These arose largely because of different ways key processes were assumed to be affected by darkness. Uptake of HTO by vegetation and the rate it is converted to OBT were prominent amongst these processes. Further research, experimental data and modelling intercomparisons are required to resolve some of these issues. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. Compton profiles and electronic structure of HgBr{sub 2} and HgI{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, G.; Dashora, Alpa [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur, 313001 Rajasthan (India); Sharma, M. [Physics Division, State Forensic Science Laboratory, Jaipur, 302016 Rajasthan (India); Ahuja, B.L. [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur, 313001 Rajasthan (India)], E-mail: blahuja@yahoo.com

    2010-02-15

    In this paper, we present the first-ever experimental Compton line shapes of HgBr{sub 2} and HgI{sub 2} using {sup 137}Cs Compton spectrometer. To compare our experimental momentum densities, we have computed the Compton profiles using Hartree-Fock and density functional theory within linear combination of atomic orbitals. We have also computed the energy bands and density of states using the linear combination of atomic orbitals and full potential linearized augmented plane wave method. On the basis of equal-valence-electron-density profiles, it is seen that HgI{sub 2} is more covalent than HgBr{sub 2} which is in agreement with the valence charge densities. The experimental isotropic profiles are found to be relatively in better agreement with the Hartree-Fock data. We have also discussed the photoluminescence and detection properties of both the halides.

  10. Quantitative interpretation of Cl, Br and I porewater concentration profiles in lake sediments of Loch Lomond, Scotland

    International Nuclear Information System (INIS)

    Falck, W.E.; Hooker, P.J.

    1991-01-01

    One of the four natural analogue sites being investigated by the British Geological Survey is Loch Lomond, Scotland. Naturally occurring halogen elements (Cl, Br and I) have been migrating from a thin marine horizon into overlying freshwater deposits by a diffusion process which has been occurring for at least 5 400 years. This report summarizes the main findings accumulated since 1983 when the work was first begun, and provides a modelling interpretation of the measured concentration-depth profiles using a new numerical code called Diagen. The release rates of I and Br from the organic matter association in the shallow buried marine layer are very slow; subsequent anion movement by diffusion is affected by tortuosity differences in the sediments rather than by chemical reaction with the sediments. The bulk of the evidence supports conservative transport of iodide, bromide and chloride anions towards the sediment/loch interface. The report discusses some implications of the findings

  11. Energy- and temperature dependences of secondary electron emission of CsI- and CsBr layers doped with Cd

    International Nuclear Information System (INIS)

    Galij, P.V.; Tsal', N.A.

    1983-01-01

    The energy and temperature dependences of the secondary electron emission coefficient (SEEC) of CsI-Cd-, CsBr-Cd-, CsI-CsBr layers have been studied. The effect of bivalent cadmium impurity on the SEEC value is investigated. It is shown that implantation of small amounts of Cd 2+ impurity into the lattice of the initial monocrystals might increase the SEEC values of the layers. Temperature dependences (TD) of SEEC are measured and the possibility of comparing experimental results with the Dekker formula is analyzed. A conclusion is drawn that the Dekker model well describes the TD of SEEC of doped layers at temperatures T < or approximately 100 deg C. At elevated temperatures., along with secondary electron scattering on phonons, one should take into account their scattering on vacancies

  12. Synthesis, Structure, and Li-Ion Conductivity of LiLa(BH4)3X, X = Cl, Br, I

    DEFF Research Database (Denmark)

    GharibDoust, Seyed Hosein Payandeh; Brighi, Matteo; Sadikin, Yolanda

    2017-01-01

    In this work, a new type of addition reaction between La(BH4)3 and LiX, X = Cl, Br, I, is used to synthesize LiLa(BH4)3Cl and two new compounds LiLa(BH4)3X, X = Br, I. This method increases the amounts of LiLa(BH4)3X and the sample purity. The highest Li-ion conductivity is observed for LiLa(BH4...... with increasing lattice parameter, that is, increasing size of the halide ion in the structure. Thus, we conclude that the sizes of both windows are important for the lithium ion conduction in LiLa(BH4)3X compounds. The lithium ion conductivity is measured over one to three heating cycles and with different...

  13. An improved method for analysis of In-EDTA, I- and Br- used as active tracers in hydrological studies

    International Nuclear Information System (INIS)

    Stanescu, S.P.; Spiridon, S.

    1992-01-01

    Neutron activation analysis combined with chemical preconcentration of the elements in water samples can give a high sensitivity in the determination of concentrations for In-EDTA, I - and Br - used as active tracers in hydrological studies. The authors have developed an improved method of analysis which is sensitive, selective and applicable to a wide range of underground and surface water samples including those having a high concentration of manganese ions. (author) 6 refs.; 2 figs.; 1 tab

  14. Permanent electric dipole moments of PtX (X = H, F, Cl, Br, and I) by the composite approach

    Science.gov (United States)

    Deng, Dan; Lian, Yongqin; Zou, Wenli

    2017-11-01

    Using the FPD composite approach of Peterson et. al. we calculate the permanent electric dipole moments of PtX (X = H, F, Cl, Br, and I) at the equilibrium geometries of their ground states. The dipole moment of PtF is estimated to be 3.421 Debye, being very close to the experimental value of 3.42(6) Debye. This research also suggests the ordering of dipole moments of PtX being proportional to the electronegativity of X.

  15. Technetium(I) complexes Tc(CO)3BrL2 (L = phosphine, pyridine, isocyanide)

    International Nuclear Information System (INIS)

    Lorenz, B.; Findeisen, M.; Olk, B.; Schmidt, K.

    1988-01-01

    Technetium pentacarbonyl bromide reacts with π-acceptor ligands L (L = phosphine, pyridine, isocyanide) to form disubstituted compounds of the type Tc(CO) 3 BrL 2 . The stereochemistry of the complexes was established by infrared and 1 H-NMR measurement. Chemical shifts and the half-widths of the 99 Tc-NMR signals are discussed. (author)

  16. Effects of thyroxine on the migration of hippocampal neurons in newborn rat exposed to HTO

    International Nuclear Information System (INIS)

    Cai Erpeng; Qiu Jun; Wang Yongsheng; Wu Cuiping; Yao Xiaobo; Wang Mingming

    2012-01-01

    Objective: To explore the effect of thyroxine (TH) on the migration of hippocampal neurons in newborn rat exposed to tritiated water (HTO). Methods: The hippocampal neurons from neonatal rats were primarily cultured, 7 days later, randomly divided into control group, HTO group, TH group and HTO + TH group (3.7 × 10 5 Bq/ml HTO and 0.3 μg/ml TH were simultaneously added). After 24 h, the distance of neuronal migration was measured with Leica AF 6000, the expressions of BDNF and Reelin mRNA in neurons were analyzed with reverse transcription polymerase chain reaction (RT-PCR), the expression of β-tubulin protein in neurons was assayed with Western blot and immunocytochemical staining. Results: Compared with control group, the expression of Reelin mRNA, BDNF mRNA and β-tubulin in HTO group were significantly reduced (t=5.80, 5.48, 5.47, P<0.01), but those in HTO + TH group and TH group were obviously increased (t=7.75, 12.06, 13.65, P<0.01; t=4.34, 5.47, 5.65, P<0.01) and higher than that in HTO group (t=2.92, 10.32, 8.76, P<0.01; t=18.07, 20.55, 40.13, P<0.01). Accordingly, the neuronal migration distance in HTO group was much shorter than that in control (t=8.62, P<0.01), and in HTO + TH group and TH group was far longer than that in control (t=7.64, 4.93, P<0.01). Moreover, the neuronal migration distance in HTO + TH group was notably elongated in comparison with that in HTO group (t=11.32, 12.31, P<0.01). Conclusions: Thyroxine may promote the migration of hippocampal neurons in newborn rat exposed to HTO. (authors)

  17. Bulk and surface band structure of the new family of semiconductors BiTeX (X=I, Br, Cl)

    International Nuclear Information System (INIS)

    Moreschini, L.; Autès, G.; Crepaldi, A.; Moser, S.; Johannsen, J.C.; Kim, K.S.; Berger, H.; Bugnon, Ph.; Magrez, A.; Denlinger, J.; Rotenberg, E.; Bostwick, A.; Yazyev, O.V.

    2015-01-01

    Highlights: • We provide an ARPES comparison between the three tellurohalides BiTeX (X = I, Br, Cl). • They present a similar band structure with namely spin-split bulk and surface states. • They offer, except for BiTeCl, the possibility of ambipolar conduction. • They can be easily doped. • From the data appeared so far, BiTeBr may be the most appealing for applications. - Abstract: We present an overview of the new family of semiconductors BiTeX (X = I, Br, Cl) from the perspective of angle resolved photoemission spectroscopy. The strong band bending occurring at the surface potentially endows them with a large flexibility, as they are capable of hosting both hole and electron conduction, and can be modified by inclusion or adsorption of foreign atoms. In addition, their trigonal crystal structure lacks a center of symmetry and allows for both bulk and surface spin-split bands at the Fermi level. We elucidate analogies and differences among the three materials, also in the light of recent theoretical and experimental work

  18. On the electronic structure and thermoelectric properties of BiTeBr and BiTeI single crystals and of BiTeI with the addition of BiI3 and CuI

    International Nuclear Information System (INIS)

    Kulbachinskii, Vladimir A.; Kytin, Vladimir G.; Kudryashov, Alexey A.; Kuznetsov, Alexei N.; Shevelkov, Andrei V.

    2012-01-01

    The electronic structures were calculated for BiTeBr and BiTeI using the density-functional theory approach and accounting for the strong spin–orbital interaction. Qualitatively, the band structures for two compounds are similar, showing strong mixing of the p states of all elements in vicinity of the Fermi level, with the band gaps of 0.595 and 0.478 eV for BiTeBr and BiTeI, respectively. The optimized crystal structures show a tendency for the Bi–X (X=Br, I) bond elongation compared to the Bi–Te one. Both compounds are intrinsic n-type semiconductors but display a metallic-like conductivity coupled to rather large thermopower, which is rationalized within the frames of the acoustic phonons scattering model. Because of larger thermopower BiTeBr exhibits a twice higher thermoelectric figure-of-merit near room temperature, ZT=0.17, compared to BiTeI. The addition of 1 mass% of BiI 3 or CuI to BiTeI decreases the mobility of electrons by two orders of magnitude, leading to significantly lower electrical conductivity, but at the same time effectively reduces the thermal conductivity. The prospects of further enhancing the thermoelectric efficiency are briefly discussed. - Graphical abstract: View of the crystal structure of BiTeBr is shown in the figure The optimized crystal structures show a tendency for the Bi–X (X=Br, I) bond elongation compared to the Bi–Te one. The electronic structures were calculated for BiTeBr and BiTeI using the density-functional theory approach and accounting for the strong spin–orbital interaction. Qualitatively, the band structures for two compounds are similar, showing strong mixing of the p states of all elements in vicinity of the Fermi level, with the band gaps of 0.595 and 0.478 eV for BiTeBr and BiTeI, respectively. Both compounds are intrinsic n-type semiconductors but display a metallic-like conductivity coupled to rather large thermopower, which is rationalized within the frames of the acoustic phonons scattering

  19. Status report on developing I-124, Pd-103, Tc-94m, Br-76 and Cu-64 radioisotopes at KIRAMS

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. H.; Kim, S. K.; Han, S. J.; Oh, T. H.; Kim, K. K.; Park, H.; Lee, J. S.; Jun, K. S. [KIRAMS, Seoul (Korea, Republic of)

    2005-07-01

    The decay characteristics of their radioisotopes such as I-124, Pd-103, Tc-94m, Br-76 and Cu-64 radionuclides produced by cyclotron have considered useful agents for diagnostic imaging or therapy. In order to increase the availability of the radionuclides, the investigation for the high capacity target design and simple procedures yielding high activities is being carried. Therefore, KIRAMS will lead researchers in nuclear medicine to access the feasibility of reliable production for enough quantities of several research radioisotopes using (p,xn) reactions. The quality and yield of products are evaluated theoretically from the excitation functions as a function of proton energies, target thickness, bombarding time, and growth time. Radionuclidic impurities are determined by gamma-spectrometer with high purity Germanium (HPGe) detector and the yields are read by ion chamber. Multi-millicuries of radioisotope I-124 (23% positron emission, half-life 4.2 days) is produced by 125-TeO2(p,2n)124-I reaction at the incident proton energy of 22 MeV. The production of carrier-free Pd-103 by the 103Rh(p,n)103Pd reaction with the 18 MeV proton beam. The electroplating method of Rh to Cu plate and recovery of rhodium from irradiated target fragments will be discussed. The thermal stability of Rh films on Cu plate will be tested for the mass production by increasing beam current up to 220uA with high-current cyclotron. For Cu-64, Tc-94m and Br-76 radionuclides, the target preparation and separating techniques are under developing. Our research project emphasis is in the development of routine methods for the production of Pd-103 radionuclide for brachytherapy seed and PET radionuclides, which include I-124, Tc-94m, Br-76 and Cu-64. In addition to the production of these radionuclides, we are developing novel radiopharmaceuticals utilizing these isotopes for both imaging and therapy.

  20. HTO/HT discriminating samplers constructed for the french experiment on the environmental behaviour of HT

    International Nuclear Information System (INIS)

    Ogram, G.L.

    1988-12-01

    The French Experiment on Environmental Tritium Behaviour was a field experiment carried out to determine the rate of formation of atmospheric HTO from a release of HT to the natural environment. The Canadian Fusion Fuels Technology Project and Ontario Hydro contributed to the project by supplying HTO/HT-discriminating, atmospheric tritium samplers. Each sampler consisted of a molecular-sieve trap to capture HTO followed by a Pd-impregnated molecular-sieve trap to oxidise and collect HT from the same air stream. This method was selected as it provided high sensitivity over short sampling periods and was convenient for field use. Laboratory tests indicated that this system measured HT concentrations reliably, but only achieved limited discrimination between HT and HTO at HTO/HT concentration ratios below 10 -2 to 10 -3 . Small cold traps were therefore operated during the French experiment in addition to the molecular-sieve samplers exhibited much improved discrimination in the field (approaching 10 4 ), possibly due to higher sampling flow rates than used in the laboratory. These results demonstrate that care should be taken in using desiccant-based, HTO/HT-discriminating samplers when the HT concentration is much higher than HTO concentration, and suggest the need to systematically characterize and perhaps improve the performance of discriminating samplers at low HTO/HT ratios

  1. INAA applied to halogen (Br and I) stability in long-term storage of lyophilized biological materials

    International Nuclear Information System (INIS)

    Zaichick, V.; Zaichick, S.

    2000-01-01

    Instrumental neutron activation analysis (INAA) was used to determine the Br and I concentration in the same ten lyophilized and homogenized human thyroid samples prior and after a 20-year storage at room temperature. It was found that long-term storage had no effect on the iodine content. At the same time, the bromine content was about 2-fold lower (p<0.01). It was assumed that possible losses of other halogens can occur under long-term storage of lyophilized biological materials at room temperature. (author)

  2. Approaching the limit of Cu(II)/Cu(I) mixed valency in a Cu(I)Br2-N-methylquinoxalinium hybrid compound.

    Science.gov (United States)

    Leblanc, Nicolas; Sproules, Stephen; Pasquier, Claude; Auban-Senzier, Pascale; Raffy, Helene; Powell, Annie K

    2015-08-18

    A novel 1D hybrid salt (MQ)[CuBr2]∞ (MQ = N-methylquinoxalinium) is reported. Structural, spectroscopic and magnetic investigations reveal a minimal Cu(II) doping of less than 0.1%. However it is not possible to distinguish Cu(I) and Cu(II). The unusually close packing of the organic moieties and the dark brown colour of the crystals suggest a defect electronic structure.

  3. A Passive Diffusion Sampler for HT- and HTO-in-Air

    International Nuclear Information System (INIS)

    Surette, R.A.; Nunes, J.C.

    2005-01-01

    Fusion research and tritium removal facilities potentially handle large inventories of tritium gas (HT). If any HT is released into the workplace, a fraction may be converted to tritiated water vapour (HTO). A convenient method to determine the activity concentration of each species is necessary to assess the potential hazard since the radiological hazard of HTO is more than 10 4 that due to HT. Passive samplers for measuring tritiated water vapour (HTO) have been shown to be suitable for use indoors and outdoors. These simple samplers consist of a standard 20-mL liquid scintillation vial with a diffusion orifice that determines the sampling rate.The total tritium samplers described herein are passive or diffusion samplers that contain a small amount of AECL-proprietary wet-proofed catalyst fixed to the underside of the sampling heads to allow conversion of the HT to HTO that is subsequently collected in the sink, (HTO), in the bottom of the sampler. After an appropriate sampling time, liquid scintillation cocktail is added to the vial and the activity collected determined by liquid scintillation analysis. When used in conjunction with the conventional HTO passive sampler the difference between the total and HTO samplers can be used to determine the HT fraction ((HT+HTO) - HTO HT). The sampling rates for the modified diffusion sampler were measured to be 4.6 and 8.1 L/d for HTO and HT, respectively. For a fifteen-minute sampling period, passive samplers can be used to measure tritium activity concentrations from 37 kBq/m 3 to 115 MBq/m 3

  4. In vitro and in vivo effects of low dose HTO contamination modulated by dose rate

    International Nuclear Information System (INIS)

    Petcu, I.; Savu, D.; Moisoi, N.; Koeteles, G.J.

    1997-01-01

    The experiment performed in vitro intended to examine whether an adaptive response could be elicited on lymphocytes by low-level contamination of whole blood with tritiated water and if the modification of the dose rate has any influence on it. Lymphocytes pre-exposed to 3 HOH (0.2 - 6.6 MBq/ml) and subsequently irradiated with I Gy γ-rays showed micronuclei frequency significantly lower (40% - 45%) than the expected member (sum of the yields induced by 3 HOH and γ-rays separately). The degree of the radioresistance induced by HTO pre-treatments became higher with decreasing dose-rate for a rather similar total adapting dose. In vivo, the aim of the study was to investigate if different dose rates are inducing modulation of the lipid peroxidation level and of the thymidine uptake in different tissues of animals contaminated by HTO ingestion. The total doses varied between 5 and 20 cGy and were delivered as chronic (100 days) or acute contamination (5 days). It was observed that only doses about 20 cGy caused a dose-rate dependent increase of the lipid peroxidation level in the tissues of small intestine, kidney and spleen. Both chronic and acute contamination did produce reduced incorporation of thymidine in the cells of bone marrow. The most effective decrease of thymidine uptake was induced by the acute contamination in the lower dose domain (approx. 5 cGy). Our hypothesis is that in this dose domain the modification of thymidine uptake could be due to changes at the level of membrane transport. (author)

  5. Flash photolysis and pulse radiolysis of the Co(sep)3+-X- (sep = sepulchrate; X = I, Br) systems in aqueous solution

    International Nuclear Information System (INIS)

    Pina, F.; Maestri, M.; Ballardini, R.; Mulazzani, Q.G.; D'Angelantonio, M.; Balzani, V.

    1986-01-01

    The Co(sep) 3+ complex (sep = sepulchrate = 1,3,6,8,10,13,16,19-octaazabicyclo[6.6.6]eicosane) in aqueous solution forms ion pairs with the I - and Br - anions, which exhibit a relatively intense charge-transfer absorption. In deoxygenated aqueous solution no net reaction is obtained upon continuous light excitation in the ion-pair charge-transfer bands, but formation of transient species is observed in flash photolysis experiments. For the Co(sep) 3+ -I - system, I 2 - ions are formed that decay in the 50-μs time scale to give I 3 - . The latter species disappears in a time scale of seconds, leading the system back to the preexcitation conditions. For the Co(sep) 3+ -Br - system, only formation of the Br 2 - transient is observed, followed by regeneration of the preexcitation conditions in the 20-μs time scale. In order to elucidate the kinetic aspects of the transient formation and disappearance, pulse radiolysis experiments on the Co(sep) 3+ -I - and Co(sep) 3+ -Br - systems have been carried out. The rate constants of the reactions of Co(sep) 2+ with I 2 - , I 3 - , and Br 2 - have been measured, and a complete picture of the redox processes that follow flash photolysis and pulse radiolysis excitations has been obtained. 5 figures

  6. 207Pb and 205Tl NMR on Perovskite Type Crystals APbX3 (A = Cs, Tl, X = Br, I)

    Science.gov (United States)

    Sharma, Surendra; Weiden, Norbert; Weiss, Alarich

    1987-11-01

    By 205Tl and 207Pb NM R the chemical shift in polycrystalline samples of binary halides AX, BX2 and ternary halides ABX3 (A = Cs, Tl; B = Pb; X = Br, I) was studied at room temperature. The chemical shift tensors δ ( 205Tl) and δ (207Pb) were determined in magnitude and orientation on single crystals of the orthorhombic TlPbI3. The components of the δ(205Tl) tensor are δx (205Tl) || a = 611ppm; δy (205Tl) || b = 680 ppm; δZ(205Tl) || c = 1329 ppm; δiso(205Tl) = 873.3 ppm (with respect to 3.4 molar aqueous solution of TlOOCCH3). The chemical shift tensor of 207Pb in TlPbI3 shows two orientations. One of them is: δx (207Pb) = 3760 ppm, inclined 30° from b towards c, δy(207Pb) || a = 3485 ppm, δz(207Pb) = 2639 ppm inclined 120° from b towards c. δiso(207Pb) = 3295 ppm (with respect to saturated aqueous solution of Pb(NO3)2). The results are discussed with respect to the crystal structure and a model to explain orientation and anisotropy of the tensors δ(205Tl) and δ(207Pb) in TlPbI3 is proposed. In the system CsPbBr3-x Ix δ(207Pb) was studied on polycrystalline samples. The chemical shift increases with increasing x and negative excess shift is observed.

  7. The behavior of 89Sr and tritium water (HTO) in a model terrestrial-aquatic ecosystem

    International Nuclear Information System (INIS)

    Zhang Yongxi; Wang Shouxiang; Chen Chuangqun; Sun Zhiming; Huang Dan; Hu Bingmin

    1993-08-01

    The effect of land polluted by 89 Sr on water body and the immigration of HTO from water body to land were studied in a modelling terrestrial-aquatic ecosystem. The results are as follows: (1) The 89 Sr in soil quickly migrated to common bean plants and its concentration in common bean plants was increasing with the time, but the concentration of 89 Sr in soil was exponentially declining with the depth. About 5% of 89 Sr was migrated to water body by rainfall then distributed to other components, and it can be concentrated by aquatics in a certain degree. (2) when HTO entered into the water body, it would migrate to other components of the ecosystem. and the HTO in the pool was linearly decreasing with the time. However, the concentration of HTO in the sediments and aquatics would firstly increase then reached the peak and went down. The tritium of HTO was existed in two forms in the sediments and aquatics, free water (HTO) and bound tritium. HTO was also migrated to the adjacent land soil and absorbed by land crop plants, within one and half months the land system contained 24% of the total tritium in the aquatic system

  8. Transformation of Sintered CsPbBr3 Nanocrystals to Cubic CsPbI3 and Gradient CsPbBrxI3-x through Halide Exchange.

    Science.gov (United States)

    Hoffman, Jacob B; Schleper, A Lennart; Kamat, Prashant V

    2016-07-13

    All-inorganic cesium lead halide (CsPbX3, X = Br(-), I(-)) perovskites could potentially provide comparable photovoltaic performance with enhanced stability compared to organic-inorganic lead halide species. However, small-bandgap cubic CsPbI3 has been difficult to study due to challenges forming CsPbI3 in the cubic phase. Here, a low-temperature procedure to form cubic CsPbI3 has been developed through a halide exchange reaction using films of sintered CsPbBr3 nanocrystals. The reaction was found to be strongly dependent upon temperature, featuring an Arrhenius relationship. Additionally, film thickness played a significant role in determining internal film structure at intermediate reaction times. Thin films (50 nm) showed only a small distribution of CsPbBrxI3-x species, while thicker films (350 nm) exhibited much broader distributions. Furthermore, internal film structure was ordered, featuring a compositional gradient within film. Transient absorption spectroscopy showed the influence of halide exchange on the excited state of the material. In thicker films, charge carriers were rapidly transferred to iodide-rich regions near the film surface within the first several picoseconds after excitation. This ultrafast vectorial charge-transfer process illustrates the potential of utilizing compositional gradients to direct charge flow in perovskite-based photovoltaics.

  9. PuBr3-type as high pressure modification of rare earth trihalides LnX3 (X = Cl, Br, I)

    International Nuclear Information System (INIS)

    Beck, H.P.; Gladrow, E.

    1983-01-01

    High pressure experiments in a belt-type apparatus were performed on rare earth trichlorides, -bromides and -iodides. The results underline the importance of the PuBr 3 -type arrangement. The range of existence of this structure type is considerably increased under pressure. X-ray high temperature investigations at ambient pressure on the quenched high pressure phases show a marked correlation between the transformation pressures, which rise with smaller cations, and the temperatures at which the high pressure phases are reconverted to the thermodynamically stable ones. (author)

  10. Detection of helium-containing paramagnetic complex at decay of tritium incorporated in HTO and DTO

    International Nuclear Information System (INIS)

    Legasov, V.A.; Usatyj, A.F.; Ibragimov, R.A.; Myasoedov, N.F.

    1979-01-01

    EPR technique was used to study the paramagnetic centers appearing during long-term storage of frozen (77 K) non-deoxygenated light (H 2 O) and heavy (D 2 O) water containing 3.5% vol. highly active HTO (29 ci/cm 3 ), so that the resulting activity of the sample (0.1 ml) was about 100 mci. For comparison, the same samples containing no HTO but irradiated by Co-60 rays were studied under identical conditions. A schematic of the processes involved in tritium decay in DTO (or HTO) in the aqueous matrix frozen at low temperatures was suggested

  11. Effects of CsBr addition on the performance of CH3NH3PbI3-xClx-based solar cells

    Science.gov (United States)

    Ueoka, Naoki; Oku, Takeo; Ohishi, Yuya; Tanaka, Hiroki; Suzuki, Atsushi; Sakamoto, Hiroki; Yamada, Masahiro; Minami, Satoshi; Tsukada, Shinichiro

    2018-01-01

    Perovskite-type photovoltaic devices were prepared by a spin-coating method using a precursor solution of CH3NH3I and lead(II) chloride in N,N-dimethylformamide. Effects of cesium bromide (CsBr) addition on the photovoltaic properties and microstructures of the perovskite phase were investigated. The fill factor was increased by adding the CsBr to the CH3NH3PbI3-xClx precursor solution, which resulted in increase of the conversion efficiency. The crystallinity of the CH3NH3PbI3-xClx perovskite phase was also improved by adding the CsBr to the H3NH3PbI3-xClx precursor solution.

  12. Silicene/germanene on MgX2(X = Cl, Br, and I) for Li-ion battery applications

    KAUST Repository

    Zhu, Jiajie

    2016-03-15

    Silicene is a promising electrode material for Li-ion batteries due to its high Li capacity and low Li diffusion barrier. Germanene is expected to show a similar performance due to its analogous structural and electronic properties. However, the performance of both the materials will be determined by the substrate, since freestanding configurations are unstable. We propose Si/MgX2 and Ge/MgX2 (X = Cl, Br, and I) as suitable hybrid structures, based on first-principles calculations. We find that Li will not cluster and that the Li capacity is very high (443 and 279 mA h g-1 for silicene and germanene on MgCl2, respectively). Sandwich structures can be used to further enhance the performance. Low diffusion barriers of less than 0.3 eV are predicted for all the hybrid structures. © The Royal Society of Chemistry 2016.

  13. Crystal structure and thermal expansion of CsCaI3:Eu and CsSrBr3:Eu scintillators

    Science.gov (United States)

    Loyd, Matthew; Lindsey, Adam; Patel, Maulik; Koschan, Merry; Melcher, Charles L.; Zhuravleva, Mariya

    2018-01-01

    The distorted-perovskite scintillator materials CsCaI3:Eu and CsSrBr3:Eu prepared as single crystals have shown promising potential for use in radiation detection applications requiring a high light yield and excellent energy resolution. We present a study using high temperature powder X-ray diffraction experiments to examine a deleterious high temperature phase transition. High temperature phases were identified through sequential diffraction pattern Rietveld refinement in GSAS II. We report the linear coefficients of thermal expansion for both high and low temperature phases of each compound. Thermal expansion for both compositions is greatest in the [0 0 1] direction. As a result, Bridgman growth utilizing a seed oriented with the [0 0 1] along the growth direction should be used to mitigate thermal stress.

  14. Multiorbital effects in strong-field ionization and dissociation of aligned polar molecules CH3I and CH3Br

    Science.gov (United States)

    Luo, Sizuo; Zhou, Shushan; Hu, Wenhui; Li, Xiaokai; Ma, Pan; Yu, Jiaqi; Zhu, Ruihan; Wang, Chuncheng; Liu, Fuchun; Yan, Bing; Liu, Aihua; Yang, Yujun; Guo, Fuming; Ding, Dajun

    2017-12-01

    Controlling the molecular axis offers additional ways to study molecular ionization and dissociation in strong laser fields. We measure the ionization and dissociation yields of aligned polar CH3X (X =I , Br) molecules in a linearly polarized femtosecond laser field. The current data show that maximum ionization occurs when the laser polarization is perpendicular to the molecular C -X axis, and dissociation prefers to occur at the laser polarization parallel to the C -X axis. The observed angular distributions suggest that the parent ions are generated by ionization from the HOMO. The angular distribution of fragment ions indicates that dissociation occurs mainly from an ionic excited state produced by ionization from the HOMO-1.

  15. Silicene/germanene on MgX2(X = Cl, Br, and I) for Li-ion battery applications

    KAUST Repository

    Zhu, Jiajie; Chroneos, Alexander; Schwingenschlö gl, Udo

    2016-01-01

    Silicene is a promising electrode material for Li-ion batteries due to its high Li capacity and low Li diffusion barrier. Germanene is expected to show a similar performance due to its analogous structural and electronic properties. However, the performance of both the materials will be determined by the substrate, since freestanding configurations are unstable. We propose Si/MgX2 and Ge/MgX2 (X = Cl, Br, and I) as suitable hybrid structures, based on first-principles calculations. We find that Li will not cluster and that the Li capacity is very high (443 and 279 mA h g-1 for silicene and germanene on MgCl2, respectively). Sandwich structures can be used to further enhance the performance. Low diffusion barriers of less than 0.3 eV are predicted for all the hybrid structures. © The Royal Society of Chemistry 2016.

  16. Development of surgical gamma probes with TlBr semiconductors and CsI(Tl) scintillators crystals

    International Nuclear Information System (INIS)

    Costa, Fabio Eduardo da

    2006-01-01

    Radio guided surgery, using probes with radiation detectors, has been prominence in the medical area in the last decade. This technique consists in injecting a radioactive substance to concentrate in tumour and assist the localization during the surgical procedure. The radio guided surgeries allowing the identification of lymph node has revolutioned the behavior of tumour in initial stadium when are being spread by lymphatic way. The conditions imposed to the surgery due the proximity between some lymph nodes, demands of the probes, a small diameters and capacity of individual identification of these lymph nodes radiolabelled by a specific tracer. The international market supplies these probes with CdTe semiconductors and scintillators, but there is some time lack a promptly technical assistance in the Brazilian market. This work developed probes with national technology, using CsI(Tl) scintillators crystals and, in substitution to CdTe crystals semiconductors, the TlBr crystal, that is a new semiconductor detector in a world-wide development, with advantages in relation to the CdTe. Both crystals have been grown in IPEN. All the necessary electronics, specially, the preamplifier, that was also a restrictive factor for development of these types of probe in the country, have been developed with components found in the national market. Systematic measures of spatial resolution, spatial selectivity, maximum sensitivity and quality of the shielding have been carried the probes development. The results have shown that the probes, one with the CsI(Tl) crystal and another with TlBr semiconductor presented the requested performance in the international literature for radio guided probes. (author)

  17. Diarylhalotelluronium(IV) cations [(8-Me2NC10H6)2TeX]+ (X = Cl, Br, I) stabilized by intramolecularly coordinating N-donor substituents.

    Science.gov (United States)

    Beckmann, Jens; Bolsinger, Jens; Duthie, Andrew; Finke, Pamela

    2013-09-14

    The stoichiometrically controlled halogenation of the intramolecularly coordinated diaryltelluride (8-Me2NC10H6)2Te using SO2Cl2, Br2 and I2 was studied. At an equimolar ratio, the diarylhalotelluronium cations [(8-Me2NC10H6)2TeX](+) (1, X = Cl; 2, X = Br; 3, X = I) formed and were isolated as 1·Cl(-)·H2O·1/2THF, 2·Br(-), and 3·I(-), respectively. When the same reactions were carried out in the presence of KPF6, 1·PF6(-) and 22·Br(-)·PF6(-) were obtained. The chlorination of (8-Me2NC10H6)2Te with an excess of SO2Cl2 occurred with a double electrophilic substitution at the 8-dimethylaminonaphthyl residues (in the ortho- and para-positions) and afforded the diaryltellurium dichloride (5,7-Cl2-8-Me2NC10H4)2TeCl2 (4). The bromination of (8-Me2NC10H6)2Te with three equivalents of Br2 took place with a single electrophilic substitution at the 8-dimethylaminonaphthyl residues (in the para-positions) and provided the diaryltellurium dibromide (5-Br-8-Me2NC10H5)2TeBr2 (5), while an excess of Br2 produced the diarylbromotelluronium cation [(5-Br-8-Me2NC10H5)2TeBr](+) (6) that was isolated as 6·Br3(-). The reaction of (8-Me2NC10H6)2Te with two or three equivalents of iodine provided 3·I3(-) and 3·I3(-)·I2, respectively. In the presence of water, 1·Cl(-)·H2O·1/2THF, 2·Br(-), 3·I(-) and 3·I3(-) hydrolyzed to give the previously known diarylhydroxytelluronium cation [(8-Me2NC10H6)2TeOH](+) (7) that was isolated as 7·Cl(-), 7·Br(-)·H2O·THF, 7·I(-) and 7·I3(-)·H2O, respectively. The molecular structures of 1-7 were investigated in the solid-state by (125)Te MAS NMR spectroscopy and X-ray crystallography and in solution by multinuclear NMR spectroscopy ((1)H, (13)C, (125)Te), electrospray mass spectrometry and conductivity measurements. The stabilization of cations 1-3 by the intramolecular coordination was estimated by DFT calculations at the B3PW91/TZ level of theory.

  18. A calculation of the physical parameters responsible for the enhancement of radiation damage due to the incorporation of Br/I atoms into the DNA

    International Nuclear Information System (INIS)

    Charlton, D.E.

    1992-01-01

    It is well known that when analogs of thymidine containing iodine or bromine are incorporated into the DNA of irradiated cells there is a decrease of the D 0 . Three mechanisms for this effect have been discussed: (a) photoactivation of the Br/I atom and the production of Auger electrons, (b) creation of highly reactive uracil radicals by the interaction of hydrated electrons with BrUdR/IUdR, leading to SSB, and (c) interference with repair or the fixation of the damage by the presence of the Br/I atoms. Experiments to investigate photoactivation of the Br/I atoms will include all three, so that knowledge of the relative size of each contribution is useful. The first process is reasonably well understood and here the second process is examined. It is assumed that the incorporated analogs only produce radicals if they are present in a region of DNA containing energy depositions. An SSB produced by this radical can combine with a nearby SSB produced by electron damage to give a DSB, thus increasing the yield of DSB compared to the yield without the analog present. The increased yields at various levels of Br/I incorporation are compared to experiment for different models of radical action

  19. Annealing Effect on (FAPbI31−x(MAPbBr3x Perovskite Films in Inverted-Type Perovskite Solar Cells

    Directory of Open Access Journals (Sweden)

    Lung-Chien Chen

    2016-09-01

    Full Text Available This study determines the effects of annealing treatment on the structure and the optical and electronic behaviors of the mixed (FAPbI31−x(MAPbBr3x perovskite system. The experimental results reveal that (FAPbI31−x(MAPbBr3x (x ~ 0.2 is an effective light-absorbing material for use in inverted planar perovskite solar cells owing to its large absorbance and tunable band gap. Therefore, good band-matching between the (FAPbI31−x(MAPbBr3x and C60 in photovoltaic devices can be controlled by annealing at various temperatures. Accordingly, an inverted mixed perovskite solar cell with a record efficiency of 12.0% under AM1.5G irradiation is realized.

  20. Tritium (HTO and OBT) uptake within the environment and the potential risks to man

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.B.; Stuart, M.; Shultz, C. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

    2014-07-01

    A series of rainbow trout experiments were conducted in the Chalk River Laboratories' (CRL) Biological Research Facility (BRF) to evaluate OBT formation in Rainbow trout. These were: 1) HTO exposure (7kBq/L in water) using un-tagged fish,2) OBT-spiked food exposure (30kBq/L) also using un-tagged fish,3) simultaneous exposure to HTO (7kBq/L in water) and OBT-spiked food (30kBq/L) using tagged fish, and 4)validation experiment (simultaneous exposure to HTO (7kBq/L in water) and OBT-spiked food (30 kBq/L)) using tagged fish.Each of the experiments was maintained for 130-150 days.Using all experimental results, tritium (HTO and OBT) dose was calculated based on Canadian fish products consumption. (author)

  1. Development and validation of a dynamical atmosphere-vegetation-soil HTO transport and OBT formation model

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Masakazu, E-mail: ohta.masakazu@jaea.go.jp [Research Group for Environmental Science, Division of Environment and Radiation, Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency (Japan); Nagai, Haruyasu [Research Group for Environmental Science, Division of Environment and Radiation, Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency (Japan)

    2011-09-15

    A numerical model simulating transport of tritiated water (HTO) in atmosphere-soil-vegetation system, and, accumulation of organically bound tritium (OBT) in vegetative leaves was developed. Characteristic of the model is, for calculating tritium transport, it incorporates a dynamical atmosphere-soil-vegetation model (SOLVEG-II) that calculates transport of heat and water, and, exchange of CO{sub 2}. The processes included for calculating tissue free water tritium (TFWT) in leaves are HTO exchange between canopy air and leaf cellular water, root uptake of aqueous HTO in soil, photosynthetic assimilation of TFWT into OBT, and, TFWT formation from OBT through respiration. Tritium fluxes at the last two processes are input to a carbohydrate compartment model in leaves that calculates OBT translocation from leaves and allocation in them, by using photosynthesis and respiration rate in leaves. The developed model was then validated through a simulation of an existing experiment of acute exposure of grape plants to atmospheric HTO. Calculated TFWT concentration in leaves increased soon after the start of HTO exposure, reaching to equilibrium with the atmospheric HTO within a few hours, and then rapidly decreased after the end of the exposure. Calculated non-exchangeable OBT amount in leaves linearly increased during the exposure, and after the exposure, rapidly decreased in daytime, and, moderately nighttime. These variations in the calculated TFWT concentrations and OBT amounts, each mainly controlled by HTO exchange between canopy air and leaf cellular water and by carbohydrates translocation from leaves, fairly agreed with the observations within average errors of a factor of two. - Highlights: > TFWT retention and OBT formation in leaves were modeled > The model fairly well calculates TFWT concentration after an acute HTO exposure > The model well assesses OBT formation and attenuation of OBT amount in leaves.

  2. Crystal and molecular structure of new fullerides (Ph4P)2C60Hal (Hal = Br, I) and (Ph4As)2C60Cl

    International Nuclear Information System (INIS)

    Gritsenko, V.V.; D'yachenko, O.A.; Shilov, G.V.; Spitsyn, N.G.; Yagubskij, E h.B.

    1997-01-01

    New stable on air fullerides (Ph 4 P) 2 C 60 Hal (Hal = Br, I) and (Ph 4 As) 2 C 60 Cl were synthesized and their crystal structure were determined. On the basis of their relative crystallochemical analysis fullerides obtained were shown to be isostructural. They are described by general formula (Ph 4 X) 2 C 60 Hal (X = H, As; Hal = Cl, Br, I) and crystallized in triclinic system. Anions C 60 - and Hal - occupy the centre-symmetrical positions, cations (PH 4 P) + and (Ph 4 As) + occupy the general positions. The main parameters of molecular structure are presented

  3. Brüsseli I (uuesti sõnastatud) määrus: kas põhjalik muutus Eesti rahvusvahelises tsiviilkohtumenetluses? / Maarja Torga

    Index Scriptorium Estoniae

    Torga, Maarja, 1984-

    2014-01-01

    Alates 10. jaan. 2015 peavad Eesti kohtud ja kohtutäiturid hakkama nn Brüsseli I määruse (EÜ/44/2001) asemel kohaldama Brüsseli I määruses (EL/1215/2012) sisalduvaid sätteid (kohtualluvuse määramise, kohtulahendite ja ametlike dokumentide tunnustamise või täitmise kohta). Ülevaade määruse kohaldamisalast ja peamistest muudatustest ning vahekorrast teiste õigusaktidega

  4. Raman and FTIR spectroscopic studies on two hydroxylated tung oils (HTO) bearing conjugated double bonds

    Science.gov (United States)

    Zhuang, Yuwei; Ren, Zhiyong; Jiang, Lei; Zhang, Jiaxiang; Wang, Huafen; Zhang, Guobao

    2018-06-01

    Tung oil (TO) was used as a model compound to study two hydroxylated tung oils (HTO), prepared from TO by either aminolysis (HTO-am) or alcoholysis (HTO-al). Main bands in Raman and FTIR spectra were initially assigned based on the detailed analysis of the compound spectra before and after exposure to elevated temperature (200 °C). The effect of heat treatment in air on spectral bands, and especially on the changes associated with double bonds, were then investigated. In the present work, changes in spectral bands due to heat treatment were compared with those revealed in the previous work of others. The results show that the conjugated triene structure of TO has been retained during alcoholysis and aminolysis, to yield the HTOs studied; yet the change of the triene structure caused by heating is different among the three samples; the H-bonding strength between OH and Cdbnd O in HTO-am is higher than that in HTO-al; the changes in HTO vOH and vCdbnd O bands in FTIR caused by the present heat treatment were significant; for TO, there is a big difference between changes in spectra as caused by thermal exposure, compared to those caused by ageing under UV light or exposure to a catalyst. The present work has laid additional groundwork for further study of the reactions of such triply conjugated double bond structures under different ageing conditions.

  5. Transfer parameters for routine release of HTO. Consideration of OBT

    International Nuclear Information System (INIS)

    Galeriu, D.; Paunescu, N.; Cotarlea

    1997-01-01

    Knowledge of the transfer parameters for tritium is a key requirement to assess the public dose or to establish Derived Release Limit (DRL) proper for a heavy water reactor. This report revised the transfer parameters used to assess tritium doses via the ingestion pathway. First, the procedure used in Canadian standard CSA-N288.1 to assess the DRL for tritium is revisited, clearing up some misunderstandings about the derivation of transfer parameters from air to forage and animal products. Secondly, we derive the transfer parameters applying conditions of full equilibrium to dynamic equations that describe the transfer of tritiated water in food. The new transfer parameters for tritiated water in food are more plant- and site-specific then the generic transfer parameters. The most important improvement is the introduction of organically bound tritium (OBT) production in plants or animal products. Bulk transfer parameters are introduced, which include OBT as well as HTO. Based on a standard Canadian diet, the dose increase considering OBT is almost 50 %. Recent experimental data obtained under equilibrium condition are discussed, and the revised transfer parameters for assessment purposes is demonstrated. (authors)

  6. Transfer parameters for routine release of HTO - consideration of OBT

    International Nuclear Information System (INIS)

    Galeriu, D.

    1994-06-01

    Knowledge of the transfer parameters for tritium is a key requirement to assess the public dose or to establish Derived Release Limits (DRL) appropriate for a heavy-water reactor. This report revises the transfer parameters used to assess tritium doses via the ingestion pathway. First, the procedure used in Canadian standard CSA-N288.1 to assess the DRL for tritium is revised, clearing up some misunderstandings about the derivation of transfer parameters for air to forage and animal products. Second, we rederive the transfer parameters, applying conditions of full equilibrium to dynamic equations that describe the transfer of tritiated water in food. The new transfer parameters for tritiated water in food are more plant- and site-specific than the generic transfer parameters. The most important improvement is the introduction of organically bound tritium (OBT) production in plants or animal products. Bulk transfer parameters are introduced, which include OBT as well as HTO. Based on a standard Canadian diet, the dose increase considering OBT is almost 50%. Recent experimental data obtained under equilibrium conditions are discussed, and the appropriateness of the revised transfer parameters for assessment purposes is demonstrated. (author). 26 refs., 7 tabs

  7. Review Essay <br>i. Disrupting the Subject: a plunderverse, after Joel Faflak <br>ii. Echoanalysis: "the feminine compulsion to repeat"

    Directory of Open Access Journals (Sweden)

    Brandy Ryan

    2011-10-01

    Full Text Available Review of Joel Faflak. <i>Romantic Psychoanalysis: The Burden of the Mysteryi>. Albany: State University of New York Press, 2008. 333 pages; paper $29.95. ISBN 978-0-7914-7269-0.

  8. Electron impact scattering study of hypohalous acids HOX (X = F, Cl, Br, I)

    Science.gov (United States)

    Yadav, Hitesh; Bhutadia, Harshad; Prajapati, Dinesh; Desai, Hardik; Vinodkumar, Minaxi; Vinodkumar, P. C.

    2018-05-01

    In this article we aim to report total cross sections (TCS) QT, total elastic cross sections (Qel), total inelastic cross sections (Qinel) i.e. (total ionizations cross sections (Qion)+total electronic excitation cross sections (Qexc)) from threshold of the target to 5000 eV energy range. We have used a well-defined theoretical methodology Spherical Complex Optical Potential (SCOP) to compute QT, Qel and Qinel and Complex Scattering Potential - ionization contribution (CSP - ic) method to report the (Qion). The cross-sectional data reported here for the Hypohalous Acids is for the first time and the present data can become a guideline for the experimentalist to study these targets.

  9. Electronic and optical properties of MAPbX3 perovskites (X = I, Br, Cl): a unified DFT and GW theoretical analysis.

    Science.gov (United States)

    Mosconi, Edoardo; Umari, Paolo; De Angelis, Filippo

    2016-10-05

    Materials engineering is a key for the enhancement of photovoltaics technology. This is particularly true for the novel class of perovskite solar cells. Accurate theoretical modelling can help establish general trends of behavior when addressing structural changes. Here, we consider the effects due to halide substitution in organohalide CH 3 NH 3 PbX 3 perovskites exploring the halide series with X = Cl, Br, I. For this task, we use accurate DFT and GW methods including spin-orbit coupling. We find the expected band gap increase when moving from X = I to Cl, in line with the experimental data. Most notably, the calculated absorption coefficients for I, Br and Cl are nicely reproducing the behavior reported experimentally. A common feature of all the simulated band structures is a significant Rashba effect. This is similar for MAPbI 3 and MAPbBr 3 while MAPbCl 3 shows in general a reduced Rashba interaction coefficient. Finally, a monotonic increase of the exciton reduced masses is calculated when moving from I to Br to Cl, in line with the stronger excitonic character of the lighter perovskite halides.

  10. A fast and feasible method for Br and I determination in whole egg powder and its fractions by ICP-MS.

    Science.gov (United States)

    Toralles, Isis Gonçalves; Coelho, Gilberto Silva; Costa, Vanize Cadeira; Cruz, Sandra Meinen; Flores, Erico Marlon Moraes; Mesko, Marcia Foster

    2017-04-15

    A method for Br and I determination in whole egg powder and its fractions (egg white and yolk) was developed by combining microwave-induced combustion (MIC) and inductively coupled plasma mass spectrometry (ICP-MS). Using the MIC method, 350mg of whole egg powder and its fractions were efficiently digested using 50mmolL -1 NH 4 OH as an absorbing solution. The limits of detection for Br and I using the MIC method followed by ICP-MS determination were 0.039 and 0.015μgg -1 , respectively. Using the proposed method, agreements with the reference values between 97 and 104% for Br and I were obtained by analysis of reference material NIST 8435. Finally, it was possible to observe that Br concentration (4.59-5.29μgg -1 ) was higher than I (0.150-2.28μgg -1 ) for all the evaluated samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Electronic structure and magnetic ordering of the semiconducting chromium trihalides CrCl3, CrBr3, and CrI3

    KAUST Repository

    Wang, Hao; Eyert, Volker; Schwingenschlö gl, Udo

    2011-01-01

    for CrBr3 as well as CrI3. The antiferromagnetic state of CrCl3 can be reproduced by introducing an on-site electron-electron repulsion. However, we observe that the ground state depends critically on the specific approach used. Our results show that a

  12. Cross sections for (p,n) and (d,2n) reactions on /sup 79/Br and /sup 127/I: An evaluation of literature and model calculated results

    Energy Technology Data Exchange (ETDEWEB)

    Lanier, R.G.; Mustafa, M.G.; West, H.I. Jr.

    1989-02-01

    We have evaluated (p,n) and (d,2n) cross sections on /sup 79/Br and /sup 127/I, and made these cross sections available for test diagnostics. We believe that these interim cross sections are of reasonable accuracy and should be used for diagnostic interpretations until more precise measurements can be made. Our evaluation consisted of a literature search and an examination of the available experimental data. These data were supplemented by statistical model calculations using both the STAPRE and ALICE codes. We found reasonably good measured data (from threshold to the peak of the excitation function) for the (p,n) reaction on both /sup 79/Br and /sup 127/I. The literature data for the (d,2n) reaction on /sup 127/I are questionable and no data were found for the (d,2n) reaction on /sup 79/Br. We have, therefore, relied completely on calculations for the (d,2n) cross sections for both /sup 79/Br and /sup 127/I. 4 figs., 5 tabs.

  13. A Study of Inverted-Type Perovskite Solar Cells with Various Composition Ratios of (FAPbI31−x(MAPbBr3x

    Directory of Open Access Journals (Sweden)

    Lung-Chien Chen

    2016-10-01

    Full Text Available This work presents mixed (FAPbI31−x(MAPbBr3x perovskite films with various composition ratios, x (x = 0–1, which are formed using the spin coating method. The structural, optical, and electronic behaviors of the mixed (FAPbI31−x(MAPbBr3x perovskite films are discussed. A device with structure glass/indium tin oxide (ITO/poly(3,4-ethylenedioxythiophene polystyrene sulfonate (PEDOT:PSS/mixed perovskite/C60/BCP/Ag was fabricated. The mixed perovskite film was an active light-harvesting layer. PEDOT:PSS was a hole transporting layer between the ITO and perovskite. Both C60 and bathocuproine (BCP were electron transporting layers. MAPbBr3 was added to FAPbI3 with a composition ratio of x = 0.2, stabilizing the perovskite phase, which exhibited a uniform and dense morphology. The optimal device exhibited band matching with C60, resulting in a low series resistance (Rsh and a high fill factor (FF. Therefore, the device with composition (FAPbI31−x(MAPbBr3x and x = 0.2 exhibited outstanding performance.

  14. Composition-dependent hot carrier relaxation dynamics in cesium lead halide (CsPbX{sub 3}, X=Br and I) perovskite nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Heejae; Jung, Seok Il; Kim, Hyo Jin; Cha, Wonhee; Sim, Eunji; Kim, Dongho [Department of Chemistry, Yonsei University, Seoul (Korea, Republic of); Koh, Weon-Kyu [Device Laboratory, Samsung Advanced Institute of Technology, Suwon (Korea, Republic of); Kim, Jiwon [School of Integrated Technology and Underwood International College, Yonsei University, Incheon (Korea, Republic of)

    2017-04-03

    Cesium-based perovskite nanocrystals (NCs) have outstanding photophysical properties improving the performances of lighting devices. Fundamental studies on excitonic properties and hot-carrier dynamics in perovskite NCs further suggest that these materials show higher efficiencies compared to the bulk form of perovskites. However, the relaxation rates and pathways of hot-carriers are still being elucidated. By using ultrafast transient spectroscopy and calculating electronic band structures, we investigated the dependence of halide in Cs-based perovskite (CsPbX{sub 3} with X=Br, I, or their mixtures) NCs on the hot-carrier relaxation processes. All samples exhibit ultrafast (<0.6 ps) hot-carrier relaxation dynamics with following order: CsPbBr{sub 3} (310 fs)>CsPbBr{sub 1.5}I{sub 1.5} (380 fs)>CsPbI{sub 3} NC (580 fs). These result accounts for a reduced light emission efficiency of CsPbI{sub 3} NC compared to CsPbBr{sub 3} NC. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Charge transfer and relativistic effects in the low-lying electronic states of CuCl, CuBr and CuI

    NARCIS (Netherlands)

    Sousa, C; de Jong, W.A.; Broer, R.; Nieuwpoort, WC

    1997-01-01

    The spectral transitions and the character of the low-lying excited states of the copper halides, CuX (X = Cl, Br, I) are studied by means of two different relativistic computational approaches. One is based on the CASSCF/CASPT2 approach with operators accounting for scalar relativistic effects

  16. Reactivity and selectivity of the electrophile aromatic substitution in the gas phase by positive 80Br and 125I decay ions

    International Nuclear Information System (INIS)

    Knust, E.J.

    1975-02-01

    The nuclear isomeric transition sup(80m)Br(IT) 80 Br or the electron capture decay 125 Xe(EC) 125 I in the presence of high concentrations of a noble gas such as Ar or Xe are suitable for the study of the electrophilic substitution of bromium or iodonium ions in the gas phase. By using this nuclear method, which, unlike physical methods, also allows the determination of the isomer distribution, the electrophilic aromatic bromation and iodation of mono-substituted benzene compounds through unsolvated positive bromine or iodine ions could be investigated for the first time using radio-gas chromatographic techniques. (orig./LH) [de

  17. Molecular structure and vibrational spectra of MHal3 (M = Sc, Y, La, Lu; Hal = F, Cl, Br, I): ab initio calculations by the CISD+Q method

    International Nuclear Information System (INIS)

    Solomonik, V.G.; Marochko, O.Yu.

    2000-01-01

    Structure and vibrational spectra of MHal 3 molecules (M = Sc, Y, La, Lu; Hal = F, Cl, Br, I) are studied by the CISD+Q method. It is ascertained that equilibrium configuration of nuclei in all the molecules, except LaF 3 , is plane (D 3h symmetry), while that of LaF 3 molecule - pyramidal (C 3c symmetry). Results of the calculations are compared with previously published experimental data. Band reference in IR spectra of ScBr 3 , YF 3 and YCl 3 molecules has been corrected [ru

  18. Lattice potential energies and thermochemical properties of triethylammonium halides (Et3NHX) (X = Cl, Br, and I)

    International Nuclear Information System (INIS)

    Liu Yupu; Tan Zhicheng; Di Youying; Xing Yiting; Zhang Peng

    2012-01-01

    Highlights: ► The crystal structures of (Et 3 NHX) (X = Cl, Br, and I) were determined. ► Lattice potential energies and ionic radius of the common cation were obtained. ► Molar enthalpies of dissolution at infinite dilution were derived. ► Relative partial molar enthalpies were derived. ► Hydration enthalpy of Et 3 NH + was calculated. - Abstract: A series of triethylammonium halides (Et 3 NHCl, Et 3 NHBr, and Et 3 NHI) was synthesized. The crystal structures of the three compounds were characterized by X-ray crystallography. The lattice potential energies and ionic radius of the common cation of the three compounds were obtained from crystallographic data. Molar enthalpies of dissolution of the compounds at various values of molality were measured in the double-distilled water at T = 298.150 K by means of an isoperibol solution-reaction calorimeter. According to Pitzer’s theory, the values of molar enthalpies of dissolution at infinite dilution and Pitzer’s parameters of the compounds were obtained. The values of apparent relative molar enthalpies, relative partial molar enthalpies of the solvent and the compounds at different molalities were derived from the experimental values of molar enthalpies of dissolution of the compounds. Finally, hydration enthalpy of the common cation Et 3 NH + was calculated to be ΔH + = −(150.386 ± 4.071) kJ · mol −1 by designing a thermochemical cycle.

  19. Brødbaking for bedre helse : en intervensjon for å fremme brødbaking hos studenter ved Universitetet i Agder, designet som en randomisert kontrollert studie

    OpenAIRE

    Larsen, Catharina

    2016-01-01

    Masteroppgave folkehelsevitenskap - Universitetet i Agder 2016 Background: Students are challenged to make healthy and independent food choices. Unhealthy diets can increase the risk of non-communicable diseases, which constitutes a public health concern. Universities represents an arena for interventions to promote healthy dietary habits. Aim: To investigate the effect of a bread baking intervention on (1) baking habits, (2) changes in motivation for bread baking and (3) assess if ther...

  20. Wet chemical synthesis and luminescence in Ca5(PO4)3M:Eu2+ (M = Br, I) phosphors for solid state lighting

    Science.gov (United States)

    Mungmode, C. D.; Gahane, D. H.; Moharil, S. V.

    2018-05-01

    A simple wet chemical synthesis of Eu2+ activated Ca5(PO4)3Br and Ca5(PO4)3I phosphors and their photoluminescence is reported. Formation of Ca5(PO4)3Br is confirmed by X-ray diffraction (XRD). Synthesized phosphors are analyzed for photoluminescence (PL) spectrum. A bright blue emission is observed when phosphors are excited by near Ultra Violet (nUV) radiations. Photoluminescence emission spectrum for (Ca0.985Eu0.015)5(PO4)3Br is centered at 457 nm and for (Ca0.985Eu0.015)5(PO4)3 I it peaks at 455 nm when excited by 365 nm near UV radiation. Eu2+ luminescence in Ca5(PO4)3Br is reported for the first time. The phosphors can be efficiently excited by nUV radiations. This shows that phosphors may be used as blue phosphor in pcLED for Solid State Lighting.

  1. Theoretical study on the molecular structure and vibrational properties, NBO and HOMO-LUMO analysis of the POX3 (X = F, Cl, Br, I) series of molecules

    Science.gov (United States)

    Galván, Jorge E.; Gil, Diego M.; Lanús, Hernán E.; Altabef, Aida Ben

    2015-02-01

    The fourth member of the series of compounds of the type POX3 with X = I was synthesized and characterized by infrared spectroscopy. The geometrical parameters and vibrational properties of POX3 (X = F, Cl, Br, I) molecules were investigated theoretically by means DFT and ab initio methods. Available geometrical and vibrational data were used together with theoretical calculations in order to obtain a set of scaled force constants. The observed trends in geometrical parameters are analyzed and compared with those obtained in a previous work for the VOX3 (X = F, Cl, Br, I) series of compounds. NBO analysis was performed in order to know the hyper-conjugative interactions that favor one structure over another. The molecular properties such as ionization potential, electron affinity, electronegativity, chemical potential, chemical hardness, softness and global electrophilicity index have been deduced from HOMO-LUMO analysis.

  2. Process of radiation damage in BaFX:Eu2+ (X=Br, I) photo-stimulable phosphor for imaging plate (IP)

    International Nuclear Information System (INIS)

    Kato, Munetaka; Takahashi, Kenji

    2005-01-01

    Imaging Plate (IP) is a 2-dimensional radiation detector utilizing photo-stimulable phosphors. Photo-stimulated luminescence (PSL) is a kind of process in radiation-induced reactions and IP can be repeatedly performed. The mechanism of PSL is reviewed and the radiation damage, which is a phenomenon that the luminescence goes down under X-ray irradiation, is also referred to. The relation between the composition of BaFX: Eu 2+ (X=Br, I), which is widely used in IPs, and the degree of radiation damage is investigated. The degree of radiation damage is smaller in the mixed crystal system of Br and I such as BaFBr 0.85 I 0.15 :Eu 2+ than in BaFBr: Eu 2+ and BaFI: Eu 2+ . This is explained by the characteristics of luminescence centers and F centers under X-ray irradiation. (author)

  3. HTO transfer from contaminated surfaces to the atmosphere: a database for model validation

    International Nuclear Information System (INIS)

    Davis, P.A.; Amiro, B.D.; Workman, W.J.G.; Corbett, B.J.

    1996-12-01

    This report comprises a detailed database that can be used to validate models of the emission of tritiated water vapour (HTO) from natural contaminated surfaces to the atmosphere. The data were collected in 1992 July during an intensive field study based on the flux-gradient method of micrometeorology. The measurements were made over a wetland area at the Chalk River Laboratories, and over a grassed field near the Pickering Nuclear Generating Station. The study sites, the sampling protocols and the analytical techniques are described in detail, and the measured fluxes are presented. The report also contains a detailed listing of HTO concentrations in air at two heights, HTO concentrations in the source compartments (soil, surface water and vegetation), supporting meteorological data, and various vegetation and soil properties. The uncertainties in all of the measured data are estimated. (author). 15 refs., 23 tabs., 9 figs

  4. Genetic and hematopoietic effects of long-term tritiated water (HTO) ingestion in mice

    International Nuclear Information System (INIS)

    Carsten, A.L.; Cronkite, E.P.

    1975-01-01

    The positive effects seen using the somewhat insensitive dominant lethal test system and the effects seen on the blood-forming cells indicates that at least in the mouse there is a hazard in the continuous ingestion of HTO at a concentration of 3 μCCi/ml. A direct comparison of these results to the human drinking an equivalent amount of HTO is impossible due to the obvious differences in water metabolism between the two species. Until further experimentation at lower levels of ingestion are completed, it is difficult to comment concerning the significance of these results as related to current concepts of maximum permissible concentration. Studies are now underway examining the possible effects of lower concentrations of chronic HTO ingestion

  5. Dissociative multiple photoionization of Br2, IBr, and I2 in the VUV and X-ray regions: a comparative study of the inner-shell processes involving Br(3d,3p,3s) and I(4d,4p,4s,3d,3p)

    International Nuclear Information System (INIS)

    Boo, Bong Hyun; Saito, Norio

    2002-01-01

    Dissociative multiple photoionization of the bromine, the iodine monobromide, and the iodine molecules in the Br(3d,3p,3s) and I(4d,4p,4s,3d,3p) inner-shell regions has been studied by using time-of-flight (TOF) mass spectrometry coupled to synchrotron radiation in the ranges of 90∼978 eV for Br 2 , 60∼133 eV for IBr, and 86∼998 eV for I 2 . Total photoion and photoion-photoion coincidence (PIPICO) yields have been recorded as functions of the photon energy. Here, giant shape resonances have been observed beyond the thresholds of the inner-shells owing to the Br(3d 10 )→Br(3d 9 -f), I(4d 10 )→I(4d 9 -f), and I(3d 10 )→I(3d 9 -f) transitions. The dissociation processes of the multiply charged parent ions have also been evaluated from variations of photoelectron-photoion coincidence (PEPICO) and PIPICO spectra with the photon energy. From each Br(3p 3/2 ) (189.9 eV) and I(4p 3/2 ) threshold (129.9 eV), quintuple ionization of the molecules begins to play important roles in the photoionization, subsequently yielding ion pairs of X 3+ -X 2+ (X=Br, I). From the I(3d 5/2 ) threshold (627.3 eV), loss of six electrons from iodine molecule additionally begins to play a minor role in the multiple photoionization, giving rise to the formation of ion pairs of either I 3+ -I 3+ or I 4+ -I 2+ . A direct comparison of the strengths and the ranges of the I(4d) and Br(3d) giant resonances was successfully made from dissociative photoionization of IBr. Over the entire energy range examined, 60< E<133 eV, biased charge spread relevant to the specific core-hole states of IBr is observed, presumably reflecting the fact that charge localizes mostly in the excited atoms, which can be accounted for mainly by a two step decay via a fast dissociation followed by autoionization upon the VUV absorption

  6. Atmospheric HT and HTO: V. distribution and large-scale circulation

    International Nuclear Information System (INIS)

    Mason, A.S.; Oestlund, H.G.

    1979-01-01

    The two major chemical forms of atmospheric tritium are water vapour (HTO) and hydrogen gas (HT). These forms have quite different sources, distributions and sinks. The chemical conversion from HT to HTO in the atmosphere proceeds with a characteristic time of 6.5 years. Combined with the radioactive decay, a net lifetime of 4.8 years is estimated for atmospheric HT. HT is released predominately at the surface in mid- to high latitudes in the northern hemisphere. A negative gradient southward has been found from aircraft transects and from sampling at surface stations. After many years of a relatively constant global inventory of 1.1 kg of tritium gas, the HT mixing ratios decreased during 1977, with the sharpest drop at high latitudes. The estimated decline in annual production was 100 g. At the end of 1977, the atmospheric HT burden was 1.0 kg, and the estimated annual release was 200 g. An unknown portion is present as T 2 gas. The effect of T 2 is to decrease the net lifetime to 3.7 years. In the troposphere, the cycle of HTO has been treated exhaustively by others. The stratospheric distribution of HTO has been sampled from aircraft, and found to increase rapidly with height above the troposphere. An annual cycle has been observed, in which the lower stratosphere is depleted during the spring, and replenished by subsidence from higher levels during summer and fall. The effects of a nuclear test by the People's Republic of China in November 1976 have been clearly observed in the stratospheric HTO; however, no HT deposition was found. Presumably, the HTO at higher levels was originally deposited by the large nuclear weapons tests of the 1960s. An estimated 5 kg of tritium are now present in the stratosphere below 19 km. (author)

  7. On the oxidation of the three-dimensional aromatics [B(12)X(12)](2-) (X=F, Cl, Br, I).

    Science.gov (United States)

    Boeré, René T; Derendorf, Janis; Jenne, Carsten; Kacprzak, Sylwia; Kessler, Mathias; Riebau, Rainer; Riedel, Sebastian; Roemmele, Tracey L; Rühle, Monika; Scherer, Harald; Vent-Schmidt, Thomas; Warneke, Jonas; Weber, Stefan

    2014-04-07

    The perhalogenated closo-dodecaborate dianions [B12 X12 ](2-) (X=H, F, Cl, Br, I) are three-dimensional counterparts to the two-dimensional aromatics C6 X6 (X=H, F, Cl, Br, I). Whereas oxidation of the parent compounds [B12 H12 ](2-) and benzene does not lead to isolable radicals, the perhalogenated analogues can be oxidized by chemical or electrochemical methods to give stable radicals. The chemical oxidation of the closo-dodecaborate dianions [B12 X12 ](2-) with the strong oxidizer AsF5 in liquid sulfur dioxide (lSO2 ) yielded the corresponding radical anions [B12 X12 ](⋅-) (X=F, Cl, Br). The presence of radical ions was proven by EPR and UV/Vis spectroscopy and supported by quantum chemical calculations. Use of an excess amount of the oxidizing agent allowed the synthesis of the neutral perhalogenated hypercloso-boranes B12 X12 (X=Cl, Br). These compounds were characterized by single-crystal X-ray diffraction of dark blue B12 Cl12 and [Na(SO2 )6 ][B12 Br12 ]⋅B12 Br12 . Sublimation of the crude reaction products that contained B12 X12 (X=Cl, Br) resulted in pure dark blue B12 Cl12 or decomposition to red B9 Br9 , respectively. The energetics of the oxidation processes in the gas phase were calculated by DFT methods at the PBE0/def2-TZVPP level of theory. They revealed the trend of increasing ionization potentials of the [B12 X12 ](2-) dianions by going from fluorine to bromine as halogen substituent. The oxidation of all [B12 X12 ](2-) dianions was also studied in the gas phase by mass spectrometry in an ion trap. The electrochemical oxidation of the closo-dodecaborate dianions [B12 X12 ](2-) (X=F, Cl, Br, I) by cyclic and Osteryoung square-wave voltammetry in liquid sulfur dioxide or acetonitrile showed very good agreement with quantum chemical calculations in the gas phase. For [B12 X12 ](2-) (X=F, Cl, Br) the first and second oxidation processes are detected. Whereas the first process is quasi-reversible (with oxidation potentials in the range between +1

  8. Behaviour of I/Br/Cl-THMs and their projected toxicities under simulated cooking conditions: Effects of heating, table salt and residual chlorine.

    Science.gov (United States)

    Yan, Mingquan; Li, Mingyang; Han, Xuze

    2016-08-15

    This study examined the effects of heating, residual chlorine and concentration of table salt on the generation of iodine-, bromine- and chlorine-containing trihalomethanes (THMs) under simulated cooking conditions. In the case of addition of either KI- or KIO3-fortified salt, total I-THM concentrations increased with increasing iodine concentration, while total Cl/Br-THM concentrations decreased. CHCl2I, CHBrClI, CHBrI2, CHBr2I and CHI3 were formed in the presence of KI salt, while only CHCl2I was formed in the presence of KIO3 salt. CHCl2I was unstable under cooking conditions, and >90% of this DBP was removed during heating, which in some cases increased the concentrations of the other I-THMs. The calculated cytotoxicity increased with addition of KI- or KIO3-fortified salt due to the generation of I-THMs, whose impact on the cytotoxicity at room temperature was equal to or five times higher, respectively, than the cytotoxicity of the simultaneously formed Cl/Br-THMs for the cases of salts. Heating decreased the cytotoxicity, except for the case of addition of KI salt, in which the calculated cytotoxicity of I-THMs increased above 150% as the temperature was increased up to 100°C. The reported results may have important implications for epidemiologic exposure assessments and, ultimately, for public health protection. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. A high quality and quantity hybrid perovskite quantum dots (CsPbX3, X= Cl, Br and I) powders synthesis via ionic displacement

    Science.gov (United States)

    Yin, Yuhang; Luan, Weiling; Zhang, Chengxi; Yang, Fuqian

    2017-12-01

    Recently, all-inorganic perovskites CsPbX3 (X= Cl, Br and I) quantum dots (QDs) have drawn great attentions because of their PL spectra tunable over the whole visible spectral region (400-700 nm) and adjustable bandgap, which revealed a promising potential on the field of photoelectronic devices, such as solar cells, LEDs and sensors. In this paper, CsPbX3 QDs and hybrid QDs, CsPbClxBr3-x and CsPbBrxI3-x were synthesized via one-step and two-step methods comparably. The optical bandgaps of CsPbCl3, CsPbBr3, and CsPbI3, were calculated as 3.08, 2.36, and 1.73eV, respectively, based on the Tauc’s equation and UV absorption spectra. Ionic displacement and phase transformation occurred during the mixing process were found based on the monitoring of PL spectra and HRTEM characterization. The long-term stability, dried, high quality and two-dimensional hybrid CsPbBrxI3-x QDs powders could be achieved via the two-step method. Polar solution inductions were used to wash and purify the CsPbX3 QDs, which help obtain of various compositions and well crystallize all-inorganic perovskites QDs powders.

  10. Brightly Luminescent and Color-Tunable Colloidal CH3NH3PbX3 (X = Br, I, Cl) Quantum Dots: Potential Alternatives for Display Technology.

    Science.gov (United States)

    Zhang, Feng; Zhong, Haizheng; Chen, Cheng; Wu, Xian-gang; Hu, Xiangmin; Huang, Hailong; Han, Junbo; Zou, Bingsuo; Dong, Yuping

    2015-04-28

    Organometal halide perovskites are inexpensive materials with desirable characteristics of color-tunable and narrow-band emissions for lighting and display technology, but they suffer from low photoluminescence quantum yields at low excitation fluencies. Here we developed a ligand-assisted reprecipitation strategy to fabricate brightly luminescent and color-tunable colloidal CH3NH3PbX3 (X = Br, I, Cl) quantum dots with absolute quantum yield up to 70% at room temperature and low excitation fluencies. To illustrate the photoluminescence enhancements in these quantum dots, we conducted comprehensive composition and surface characterizations and determined the time- and temperature-dependent photoluminescence spectra. Comparisons between small-sized CH3NH3PbBr3 quantum dots (average diameter 3.3 nm) and corresponding micrometer-sized bulk particles (2-8 μm) suggest that the intense increased photoluminescence quantum yield originates from the increase of exciton binding energy due to size reduction as well as proper chemical passivations of the Br-rich surface. We further demonstrated wide-color gamut white-light-emitting diodes using green emissive CH3NH3PbBr3 quantum dots and red emissive K2SiF6:Mn(4+) as color converters, providing enhanced color quality for display technology. Moreover, colloidal CH3NH3PbX3 quantum dots are expected to exhibit interesting nanoscale excitonic properties and also have other potential applications in lasers, electroluminescence devices, and optical sensors.

  11. NMR espectroscopic parameters of HX and Si (Sn)X{sub 4} (X = H, F, Cl, Br and I) and SnBr{sub 4-n}I{sub n} model compounds

    Energy Technology Data Exchange (ETDEWEB)

    Maldonado, Alejandro F.; Gimenez, Carlos A. [Physics Department, Natural and Exact Science Faculty, Northeastern University of Argentina and Institute of Modelling and Innovation on Technology, IMIT Avda Libertad 5460, W3404AAS Corrientes (Argentina); Aucar, Gustavo A., E-mail: gaa@unne.edu.ar [Physics Department, Natural and Exact Science Faculty, Northeastern University of Argentina and Institute of Modelling and Innovation on Technology, IMIT Avda Libertad 5460, W3404AAS Corrientes (Argentina)

    2012-02-20

    Graphical abstract: Optimized fully relativistic calculations of NMR J-couplings (HBr, HI), chemical shifts (Si, Sn) and absolute shielding for reference compounds of heavy atoms (Si, Sn) are given. Highlights: Black-Right-Pointing-Pointer In this article we show a procedure to get accurate NMR {sigma}{sup Ref} of Si and Sn. Black-Right-Pointing-Pointer Calculations of {sigma} on more than three heavy-atom-containing molecules are given. Black-Right-Pointing-Pointer Our results are closer to {delta}{sup exp} than previous calculations for SnX{sub 4} (X = H, Cl, Br, I). Black-Right-Pointing-Pointer Optimized basis sets were considered for full R and NR calculations of NMR J and {sigma}. Black-Right-Pointing-Pointer Relativistic effects enlarge electron correlation effects on J-couplings. - Abstract: The NMR spectroscopic parameters are largely influenced by relativistic effects. They are highly dependent on the electronic behavior inside the spatial regions occupied by nuclei. Full relativistic calculations of indirect nuclear spin-spin couplings at random phase level of approach (RPA) in the title compounds with reoptimized Dyall cVTZ basis sets are given. A comparison with the results of calculations with other basis sets that are mostly used within the non-relativistic (NR) domain is presented. We analyzed the dependence of that couplings with the speed of light over the whole range of values, from the full relativistic to the NR regimes. Within this last regime, calculations at the second-order level of approach (SOPPA) indicated that electron correlation effects may not be as important for nuclear magnetic shieldings, but they must be included with care for J-coupling calculations. From these calculations, we determined that relativity enlarges the electron correlation effects of the J-couplings of HBr and HI. Because the results of nuclear magnetic shielding calculations within polarization propagators at the RPA level were reliable, we were able to show a new

  12. A simple access to pure thorium(IV) halides (ThCl{sub 4}, ThBr{sub 4}, and ThI{sub 4})

    Energy Technology Data Exchange (ETDEWEB)

    Deubner, H. Lars; Rudel, Stefan Sebastian; Kraus, Florian [Fachbereich Chemie, Philipps-Universitaet Marburg (Germany)

    2017-12-13

    In this work we present a facile, lab scale synthesis for thorium tetrahalides ThX{sub 4} (X = Cl, Br, and I). The reaction between the easily available ThO{sub 2} and AlX{sub 3} (X = Cl, Br, and I) and a subsequent in situ chemical vapor transport (CVT) leads to a product of high purity, which is obtained in the form of crystals or large aggregates of crystals. Their identity and purity was evidenced by X-ray powder diffraction and IR spectroscopy. The usage of ThO{sub 2} avoids, unlike earlier syntheses, the utilization of scarcely available thorium metal or of other reactants, such as CCl{sub 4}, which leads to impurities. Furthermore, the reaction tolerates even less pure ThO{sub 2}. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Electrochemistry in near-critical and supercritical fluids. 3. Studies of Br/sup -/, I/sup -/, and hydroquinone in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Flarsheim, W.J.; Tsou, Y.M.; Trachtenberg, I.; Johnston, K.P.; Bard, A.J.

    1986-07-31

    A new type of apparatus has been constructed for carrying out electrochemistry in near-critical and supercritical aqueous solutions. The following systems have been studied at a platinum electrode: H/sub 2/O/O/sub 2/, I/sup -//I/sub 2/, Br/sup -//Br/sub 2/, and hydroquinone/benzoquinone. The compact alumina flow cell can be heated or cooled quickly and can be recharged with fresh electrolyte solution while at high temperature and pressure. A large reduction in the potential required for the electrolysis of water was observed. Diffusivities have been measured for iodide ions and hydroquinone. General agreement with the Stokes-Einstein model was observed in the temperature range 25-375/sup 0/C.

  14. Electronic structure and magnetic ordering of the semiconducting chromium trihalides CrCl3, CrBr3, and CrI3

    KAUST Repository

    Wang, Hao

    2011-03-01

    We present results from an electronic structure investigation of the chromium halides CrCl3, CrBr3, and CrI3, as obtained by the linearized augmented plane wave method of density functional theory. Our interest focuses on the chloride. While all three halides display strong ferromagnetic coupling within the halide-Cr-halide triple layers, our emphasis is on differences in the interlayer magnetic coupling. In agreement with experimental results, our calculations indicate ferromagnetic ordering for CrBr3 as well as CrI3. The antiferromagnetic state of CrCl3 can be reproduced by introducing an on-site electron-electron repulsion. However, we observe that the ground state depends critically on the specific approach used. Our results show that a low temperature structural phase transition from monoclinic to trigonal is energetically favourable for CrCl3. © 2011 IOP Publishing Ltd.

  15. Crystal-field analysis of U3+ ions in K2LaX5 (X=Cl, Br or I) single crystals

    Science.gov (United States)

    Karbowiak, M.; Edelstein, N.; Gajek, Z.; Drożdżyński, J.

    1998-11-01

    An analysis of low temperature absorption spectra of U3+ ions doped in K2LaX5 (X=Cl, Br or I) single crystals is reported. The energy levels of the U3+ ion in the single crystals were assigned and fitted to a semiempirical Hamiltonian representing the combined atomic and crystal-field interactions at the Cs symmetry site. An analysis of the nephelauxetic effect and crystal-field splittings in the series of compounds is also reported.

  16. First-principles investigations on the mechanical, thermal, electronic, and optical properties of the defect perovskites Cs2Sn X 6 ( X = Cl, Br, I)

    International Nuclear Information System (INIS)

    Huang Hai-Ming; Jiang Zhen-Yi; Luo Shi-Jun

    2017-01-01

    The mechanical properties, thermal properties, electronic structures, and optical properties of the defect perovskites Cs 2 Sn X 6 ( X = Cl, Br, I) were investigated by first-principles calculation using PBE and HSE06 hybrid functional. The optic band gaps based on HSE06 are 3.83 eV for Cs 2 SnCl 6 , 2.36 eV for Cs 2 SnBr 6 , and 0.92 eV for Cs 2 SnI 6 , which agree with the experimental results. The Cs 2 SnCl 6 , Cs 2 SnBr 6 , and Cs 2 SnI 6 are mechanically stable and they are all anisotropic and ductile in nature. Electronic structures calculations show that the conduction band consists mainly of hybridization between the halogen p orbitals and Sn 5s orbitals, whereas the valence band is composed of the halogen p orbitals. Optic properties indicate that these three compounds exhibit good optical absorption in the ultraviolet region, and the absorption spectra red shift with the increase in the number of halogen atoms. The defect perovskites are good candidates for probing the lead-free and high power conversion efficiency of solar cells. (paper)

  17. Nanocrystals of Cesium Lead Halide Perovskites (CsPbX₃, X = Cl, Br, and I): Novel Optoelectronic Materials Showing Bright Emission with Wide Color Gamut.

    Science.gov (United States)

    Protesescu, Loredana; Yakunin, Sergii; Bodnarchuk, Maryna I; Krieg, Franziska; Caputo, Riccarda; Hendon, Christopher H; Yang, Ruo Xi; Walsh, Aron; Kovalenko, Maksym V

    2015-06-10

    Metal halides perovskites, such as hybrid organic-inorganic CH3NH3PbI3, are newcomer optoelectronic materials that have attracted enormous attention as solution-deposited absorbing layers in solar cells with power conversion efficiencies reaching 20%. Herein we demonstrate a new avenue for halide perovskites by designing highly luminescent perovskite-based colloidal quantum dot materials. We have synthesized monodisperse colloidal nanocubes (4-15 nm edge lengths) of fully inorganic cesium lead halide perovskites (CsPbX3, X = Cl, Br, and I or mixed halide systems Cl/Br and Br/I) using inexpensive commercial precursors. Through compositional modulations and quantum size-effects, the bandgap energies and emission spectra are readily tunable over the entire visible spectral region of 410-700 nm. The photoluminescence of CsPbX3 nanocrystals is characterized by narrow emission line-widths of 12-42 nm, wide color gamut covering up to 140% of the NTSC color standard, high quantum yields of up to 90%, and radiative lifetimes in the range of 1-29 ns. The compelling combination of enhanced optical properties and chemical robustness makes CsPbX3 nanocrystals appealing for optoelectronic applications, particularly for blue and green spectral regions (410-530 nm), where typical metal chalcogenide-based quantum dots suffer from photodegradation.

  18. Relative transport of water (H2O) and tritiated water (HTO) across cellulose acetate (CA) membranes

    International Nuclear Information System (INIS)

    Prabhakar, S.; Misra, B.M.; Ramani, M.P.S.

    1986-01-01

    The relative transport characteristics of water (H 2 O) and tritiated water (HTO) were evaluated through cellulose acetate membranes under osmosis, reverse osmosis and pervaporation. The results indicate that the relative transport is independent of the process. The anamolous observations under osmotic conditions are explained. (orig.)

  19. Isotope exchange between alkaline earth metal hydroxide and HTO water in the equilibrium state

    International Nuclear Information System (INIS)

    Imaizumi, H.; Gounome, J.; Kano, N.

    1997-01-01

    In order reveal to what extent tritium ( 3 H or T) can be incorporated into hydroxides, the isotope exchange reaction (OT-for-OH exchange reaction) between each alkaline earth metal hydroxide (M(OH) 2 ), where M means alkaline earth metal (M=Ca, Sr or Ba) and HTO water was observed homogeneously at 30 deg C under equilibrium after mixing. Consequently, the followings were obtained: a quantitative relation between the electronegativity of each M ion and the ability (of the M ion) incorporating OT - into the M hydroxide can be found and the ability is small when the temperature is high, the exchange rate for the OT-for-OH exchange reaction is small when the electronegativity of the M ion in the M hydroxide is great, as for the dissociation of HTO water, it seems that formula (HTO ↔ T + + OH - ) is more predominant than the formula (HTO ↔H + + OT - ) when the temperature is high and the method used in this work is useful to estimate the reactivity of a certain alkaline material. (author)

  20. Dissociative photoionization of IBr following I(4d) and Br(3d) inner-shell excitations in the range of 60 ∼ 133 eV: remarkable biased charge spread relevant to the core-hole states

    International Nuclear Information System (INIS)

    Boo, Bong Hyun; Koyano, Inosuke

    2002-01-01

    Dissociative photoionization of an interhalogen molecule, iodine monobromide (IBr), spanning the I(4d) and the Br(3d) inner-shell excitation/ionization regions has been studied by using time-of-flight (TOF) mass spectrometry coupled to synchrotron radiation in the range of 60 ∼ 133 eV. The total and the individual photoion yields have been recorded as functions of the photon energy. Here, a giant shape resonance has been observed owing to the I(4d 10 ) →I(4d 9 εf) transition, the transition probability for which outweighs that for the Br(3d 10 ) →Br(3d 9 εf) excitation. In addition to the huge resonance, discrete resonances owing to the Br(3d) -1 IBr(4pσ + ) and the Br(3d -1 )Br(5p) transitions, with very weak intensities, are observed at 70.5 and 73.6 eV and have spin-orbit splittings of = 1.0 and = 0.9 eV, respectively. The dissociation processes of singly and doubly charged parent ions have also been evaluated from the variations of the individual ion and photoion-photoion coincidence (PIPICO) yields with the photon energy. Below the Br(3d) threshold, including the Br(3d) discrete excitation region, 60 + and I 2+ ions are exclusively formed with a trace number of Br + ions. Slightly above the Br(3d) threshold, more specifically at 77.5 eV, however, photoionization events leading to the formations of Br + and Br 2- prevail. At higher energies beyond the Br(3d) threshold, 78 + and I 2+ turn out to exceed again those for Br + and Br 2+ , respectively. Over the entire energy range examined, a remarkable biased charge spread in dissociative photoionization events is observed, presumably reflecting the fact that charge localized mostly in the excited atoms relevant to the specific inner-shell excitation, which can be accounted for mainly by a two-step decay process via a fast dissociation followed by autoionization upon vuv absorption

  1. Benzofuroxan derivatives N-Br and N-I induce intrinsic apoptosis in melanoma cells by regulating AKT/BIM signaling and display anti metastatic activity in vivo.

    Science.gov (United States)

    Farias, C F; Massaoka, M H; Girola, N; Azevedo, R A; Ferreira, A K; Jorge, S D; Tavares, L C; Figueiredo, C R; Travassos, L R

    2015-10-27

    Malignant melanoma is an aggressive type of skin cancer, and despite recent advances in treatment, the survival rate of the metastatic form remains low. Nifuroxazide analogues are drugs based on the substitution of the nitrofuran group by benzofuroxan, in view of the pharmacophore similarity of the nitro group, improving bioavailability, with higher intrinsic activity and less toxicity. Benzofuroxan activity involves the intracellular production of free-radical species. In the present work, we evaluated the antitumor effects of different benzofuroxan derivatives in a murine melanoma model. B16F10-Nex2 melanoma cells were used to investigate the antitumor effects of Benzofuroxan derivatives in vitro and in a syngeneic melanoma model in C57Bl/6 mice. Cytotoxicity, morphological changes and reactive oxygen species (ROS) were assessed by a diphenyltetrasolium reagent, optical and fluorescence microscopy, respectively. Annexin-V binding and mitochondrial integrity were analyzed by flow cytometry. Western blotting and colorimetry identified cell signaling proteins. Benzofuroxan N-Br and N-I derivatives were active against murine and human tumor cell lines, exerting significant protection against metastatic melanoma in a syngeneic model. N-Br and N-I induce apoptosis in melanoma cells, evidenced by specific morphological changes, DNA condensation and degradation, and phosphatidylserine translocation in the plasma membrane. The intrinsic mitochondrial pathway in B16F10-Nex2 cells is suggested owing to reduced outer membrane potential in mitochondria, followed by caspase -9, -3 activation and cleavage of PARP. The cytotoxicity of N-Br and N-I in B16F10-Nex2 cells is mediated by the generation of ROS, inhibited by pre-incubation of the cells with N-acetylcysteine (NAC). The induction of ROS by N-Br and N-I resulted in the inhibition of AKT activation, an important molecule related to tumor cell survival, followed by upregulation of BIM. We conclude that N-Br and N-I are

  2. Benzofuroxan derivatives N-Br and N-I induce intrinsic apoptosis in melanoma cells by regulating AKT/BIM signaling and display anti metastatic activity in vivo

    International Nuclear Information System (INIS)

    Farias, C. F.; Massaoka, M. H.; Girola, N.; Azevedo, R. A.; Ferreira, A. K.; Jorge, S. D.; Tavares, L. C.; Figueiredo, C. R.; Travassos, L. R.

    2015-01-01

    Malignant melanoma is an aggressive type of skin cancer, and despite recent advances in treatment, the survival rate of the metastatic form remains low. Nifuroxazide analogues are drugs based on the substitution of the nitrofuran group by benzofuroxan, in view of the pharmacophore similarity of the nitro group, improving bioavailability, with higher intrinsic activity and less toxicity. Benzofuroxan activity involves the intracellular production of free-radical species. In the present work, we evaluated the antitumor effects of different benzofuroxan derivatives in a murine melanoma model. B16F10-Nex2 melanoma cells were used to investigate the antitumor effects of Benzofuroxan derivatives in vitro and in a syngeneic melanoma model in C57Bl/6 mice. Cytotoxicity, morphological changes and reactive oxygen species (ROS) were assessed by a diphenyltetrasolium reagent, optical and fluorescence microscopy, respectively. Annexin-V binding and mitochondrial integrity were analyzed by flow cytometry. Western blotting and colorimetry identified cell signaling proteins. Benzofuroxan N-Br and N-I derivatives were active against murine and human tumor cell lines, exerting significant protection against metastatic melanoma in a syngeneic model. N-Br and N-I induce apoptosis in melanoma cells, evidenced by specific morphological changes, DNA condensation and degradation, and phosphatidylserine translocation in the plasma membrane. The intrinsic mitochondrial pathway in B16F10-Nex2 cells is suggested owing to reduced outer membrane potential in mitochondria, followed by caspase −9, −3 activation and cleavage of PARP. The cytotoxicity of N-Br and N-I in B16F10-Nex2 cells is mediated by the generation of ROS, inhibited by pre-incubation of the cells with N-acetylcysteine (NAC). The induction of ROS by N-Br and N-I resulted in the inhibition of AKT activation, an important molecule related to tumor cell survival, followed by upregulation of BIM. We conclude that N-Br and N-I are

  3. The binding of platinum hexahalides (Cl, Br and I) to hen egg-white lysozyme and the chemical transformation of the PtI{sub 6} octahedral complex to a PtI{sub 3} moiety bound to His15

    Energy Technology Data Exchange (ETDEWEB)

    Tanley, Simon W. M.; Starkey, Laurina-Victoria; Lamplough, Lucinda; Kaenket, Surasek; Helliwell, John R., E-mail: john.helliwell@manchester.ac.uk [University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom)

    2014-08-29

    The platinum hexahalides have an octahedral arrangement of six halogen atoms bound to a Pt centre, thus having an octahedral shape that could prove to be useful in interpreting poor electron-density maps. In a detailed characterization, PtI{sub 6} chemically transformed to a square-planar PtI{sub 3} complex bound to the N{sup δ} atom of His15 of HEWL was also observed, which was not observed for PtBr{sub 6} or PtCl{sub 6}. This study examines the binding and chemical stability of the platinum hexahalides K{sub 2}PtCl{sub 6}, K{sub 2}PtBr{sub 6} and K{sub 2}PtI{sub 6} when soaked into pre-grown hen egg-white lysozyme (HEWL) crystals as the protein host. Direct comparison of the iodo complex with the chloro and bromo complexes shows that the iodo complex is partly chemically transformed to a square-planar PtI{sub 3} complex bound to the N{sup δ} atom of His15, a chemical behaviour that is not exhibited by the chloro or bromo complexes. Each complex does, however, bind to HEWL in its octahedral form either at one site (PtI{sub 6}) or at two sites (PtBr{sub 6} and PtCl{sub 6}). As heavy-atom derivatives of a protein, the octahedral shape of the hexahalides could be helpful in cases of difficult-to-interpret electron-density maps as they would be recognisable ‘objects’.

  4. La5M3X (M=Sn, Bi; X=Cl, Br, I): exploring the limit of the Mn5Si3-type hosting lattice

    International Nuclear Information System (INIS)

    Zheng Chong; Mattausch, Hansjuergen; Simon, Arndt

    2002-01-01

    Three new compounds add to the family of the Mn 5 Si 3 type host-guest lattice. These are La 5 Sn 3 X (X=Cl, Br, I) synthesized from stoichiometric mixtures of La, LaX 3 and Sn heated under Ar atmosphere in sealed Ta ampoules at 850-990 deg. C for 13-62 days. La 5 Sn 3 X crystallize in the space group P6 3 /mcm (No. 193) with lattice parameters a=9.603(1) A, 9.637(1) A and 9.673(1) A; c=6.890(1) A, 6.931(1) A and 6.987(1) A, respectively, for X=Cl, Br and I. Computational analysis using both the extended Hueckel and the local density functional methods showed that the Sn and La site acts as electron reservoir, providing electrons to the interstitials as necessary. This gives rise to a metallic behavior. Susceptibility and conductivity measurements confirmed these predictions. The single crystal structure of La 5 Bi 3 Br is also reported

  5. I nöd och lust : En praktisk studie om hållbara bröllopssminkningar inspirerat av årstidernas färger

    OpenAIRE

    Guldbrand, Ida

    2016-01-01

    Syftet med detta arbete är att beskriva med vilka sminktekniker och produkter man får till hållbara bröllopssminkningar inspirerade av årstidernas färger, för att visa hur färger, tekniker och produkter anpassas i bröllopssminkningar. Detta för att visa de egna kunskaperna inom området och för att kunna inspirera blivande brudar. Arbetet kommer även vara till nytta för estenomer, branschmänniskor och andra människor som är intresserade av området då de också kan inspireras av arbetet. So...

  6. Tritium uptake in rainbow trout (Oncorhynchus mykiss): HTO and OBT-spiked feed exposures simultaneously

    International Nuclear Information System (INIS)

    Kim, S.B.; Shultz, C.; Stuart, M.; Festarini, A.

    2015-01-01

    There is currently considerable interest in organically bound tritium (OBT) formation in edible fish. The major questions revolve around whether or not tritium can accumulate in fish after being released into aquatic environments. Since OBT formation rates in large, edible fish are poorly understood, rainbow trout (Oncorhynchus mykiss) studies, where fish were simultaneously exposed to tritiated water (HTO) and OBT-spiked feed over 130 days, were conducted to evaluate tritium uptake. The measured HTO activity concentrations in fish tissue confirmed that HTO in fish tissue equilibrates quickly with HTO in tank water. The data obtained also confirmed that OBT uptake is faster when fish are ingesting OBT-spiked feed compared to when fish are living in tritiated water (and consuming non-OBT-spiked feed). The difference between the two exposure types is such that the groups exposed to tritiated water and OBT-spiked feed simultaneously were showing the same uptake rates as OBT-spiked feed only exposures. Contrary to what was expected, the rate of OBT uptake (from OBT-spiked feed) seemed to be higher in slow growing fish compared to fast growing fish. Another observation from these studies was that OBT activity concentrations in all organs (viscera) had a tendency to be higher than OBT activity concentrations measured in fish flesh. - Highlights: • Edible size of rainbow trout (Oncorhynchus mykiss) were simultaneously exposed to tritiated water (HTO) and OBT-spiked feed over 130 days. • OBT uptake is faster when fish are ingesting OBT-spiked feed compared to when fish are living in tritiated water (and consuming non-OBT-spiked feed). • The rate of OBT uptake (from OBT-spiked feed) seemed to be higher in slow growing fish compared to fast growing fish

  7. Germylenes: structures, electron affinities, and singlet-triplet gaps of the conventional XGeCY(3) (X = H, F, Cl, Br, and I; Y = F and Cl) species and the unexpected cyclic XGeCY(3) (Y = Br and I) systems.

    Science.gov (United States)

    Bundhun, Ashwini; Abdallah, Hassan H; Ramasami, Ponnadurai; Schaefer, Henry F

    2010-12-23

    A systematic investigation of the X-Ge-CY(3) (X = H, F, Cl, Br, and I; Y = F, Cl, Br, and I) species is carried out using density functional theory. The basis sets used for all atoms (except iodine) in this work are of double-ζ plus polarization quality with additional s- and p-type diffuse functions, and denoted DZP++. Vibrational frequency analyses are performed to evaluate zero-point energy corrections and to determine the nature of the stationary points located. Predicted are four different forms of neutral-anion separations: adiabatic electron affinity (EA(ad)), zero-point vibrational energy corrected EA(ad(ZPVE)), vertical electron affinity (EA(vert)), and vertical detachment energy (VDE). The electronegativity (χ) reactivity descriptor for the halogens (X = F, Cl, Br, and I) is used as a tool to assess the interrelated properties of these germylenes. The topological position of the halogen atom bound to the divalent germanium center is well correlated with the trend in the electron affinities and singlet-triplet gaps. For the expected XGeCY(3) structures (X = H, F, Cl, Br, and I; Y = F and Cl), the predicted trend in the electron affinities is well correlated with simpler germylene derivatives (J. Phys. Chem. A 2009, 113, 8080). The predicted EA(ad(ZPVE)) values with the BHLYP functional range from 1.66 eV (FGeCCl(3)) to 2.20 eV (IGeCF(3)), while the singlet-triplet splittings range from 1.28 eV (HGeCF(3)) to 2.22 eV (FGeCCl(3)). The XGeCY(3) (Y = Br and I) species are most often characterized by three-membered cyclic systems involving the divalent germanium atom, the carbon atom, and a halogen atom.

  8. Organically bound tritium (OBT) formation in rainbow trout (Oncorhynchus mykiss): HTO and OBT-spiked food exposure experiments

    International Nuclear Information System (INIS)

    Kim, S.B.; Shultz, C.; Stuart, M.; McNamara, E.; Festarini, A.; Bureau, D.P.

    2013-01-01

    In order to determine the rate of organically bound tritium (OBT) formation, rainbow trout (Oncorhynchus mykiss) were exposed to tritiated water (HTO) or OBT-spiked food. The HTO (in water) exposure study was conducted using a tritium activity concentration of approximately 7000 Bq/L and the OBT (in food) exposure study was conducted using a tritium activity concentration of approximately 30,000 Bq/L. Fish in both studies were expected to be exposed to similar tritium levels assuming 25% incorporation of the tritiated amino acids found in the food. Four different sampling campaigns of HTO exposure (Day 10, 30, 70, 140) and five different sampling campaigns of OBT-spiked food exposure (Day 9, 30, 70, 100, 140) were conducted to measure HTO and OBT activity concentrations in fish tissues. OBT depuration was also evaluated over a period of 30 days following the 140 d exposure studies. The results suggested that the OBT formation rate was slower when the fish were exposed to HTO compared to when the fish were ingesting OBT. In addition, the results indicated that OBT can bioaccumulate in fish tissues following OBT-spiked food exposure. - Highlights: ► The rate of organically bound tritium (OBT) formation was determined in rainbow trout. ► Rainbow trout were exposed to tritium in the form of tritiated water (HTO) and OBT-spiked food. ► OBT formation rate was slower when the fish were exposed to HTO compared to when the fish were ingesting OBT.

  9. HTO and OBT activity concentrations in soil at the historical atmospheric HT release site (Chalk River Laboratories)

    International Nuclear Information System (INIS)

    Kim, S.B.; Bredlaw, M.; Korolevych, V.Y.

    2012-01-01

    Tritium is routinely released by the Chalk River Laboratories (CRL) nuclear facilities. Three International HT release experiments have been conducted at the CRL site in the past. The site has not been disturbed since the last historical atmospheric testing in 1994 and presents an opportunity to assess the retention of tritium in soil. This study is devoted to the measurement of HTO and OBT activity concentration profiles in the subsurface 25 cm of soil. In terms of soil HTO, there is no evidence from the past HT release experiments that HTO was retained. The HTO activity concentration in the soil pore water appears similar to concentrations found in background areas in Ontario. In contrast, OBT activity concentrations in soil at the same site were significantly higher than HTO activity concentrations in soil. Elevated OBT appears to reside in the top layer of the soil (0–5 cm). In addition, OBT activity concentrations in the top soil layer did not fluctuate much with season, again, quite in contrast with soil HTO. This result suggests that OBT activity concentrations retained the signature of the historical tritium releases. Highlights: ► At the historical HT release site, HTO and OBT activity concentrations in soil depths were investigated. ► Most organically bound tritium exists in the top layer of the soil. ► The results indicated that OBT activity concentrations can be reflective of historical tritium releases into the environment.

  10. Türkiye Göçmeni Ve Yerli Kıbrıslılarda Dindarlık: Kuzey Kıbrıs Türk Cumhuriyeti Örneği

    Directory of Open Access Journals (Sweden)

    Asım Yapıcı

    2015-12-01

    Full Text Available Bu çalışmada, Kuzey Kıbrıs Türk Cumhuriyeti (KKTC vatandaşlarının dindarlık görüntüleri, sosyo-demografik değişkenler açısından incelenmiştir. Araştırmanın verilerini toplamak üzere hazırlanan anket formunda cinsiyet, yaş, eğitim düzeyi, köken, ikamet gibi sosyo-demografik değişkenler ve “Bir yaratıcının varlığına inanma”, “Allah’ın varlığını hissetme”, “namaz kılma”, “oruç tutma” ve “dua etme” sıklığını tespit etmeye yönelik dinî değişkenler kullanılmıştır. Tarama modelinde yürütülen çalışma, basit rastlantısal yöntemle seçilen 194’ü erkek, 207’si kadın toplam 401 kişiden oluşmaktadır. Verilerin analizinde t-testi, tek yönlü varyans analizi ve Pearson korelasyon teknikleri kullanılmıştır. Araştırma sonucunda, kökene (Türkiye Göçmeni ve Yerli Kıbrıslı göre dinî değişkenlerin tamamında Türkiye Göçmenleri lehinde anlamlı farklılıkların olduğu anlaşılmıştır. Katılımcıların dindarlık görüntülerinin cinsiyete, ikamete ve eğitim düzeyine göre anlamlı farklılaştığı, yaşa göre ise anlamlı bir fark bulunmadığı görülmüştür.

  11. The study of structural, elastic, electronic and optical properties of CsYx I(1 − x(Y = F, Cl, Br using density functional theory

    Directory of Open Access Journals (Sweden)

    Mian Shabeer Ahmad

    2017-04-01

    Full Text Available The structural, electronic, elastic and optical properties of CsYx I(1 − x(Y = F, Cl, Br are investigated using full potential linearized augmented plane wave (FP-LAPW method within the generalized gradient approximation (GGA. The ground state properties such as lattice constant (ao and bulk modulus (K have been calculated. The mechanical properties including Poisson’s ratio (σ, Young’s modulus (E, anisotropy factor (A and shear modulus (G were also calculated. The results of these calculations are comparable with the reported experimental and theoretical values. The ductility of CsYx I(1 − x was analyzed using Pugh’s rule (B/G ratio and Cauchy’s pressure (C12−C44. Our results revealed that CsF is the most ductile among the CsYxI(1 − x(Y = F, Cl, Br compounds. The incremental addition of lighter halogens (Yx slightly weakens the strength of ionic bond in CsYxI(1 − x. Moreover, the optical transitions were found to be direct for binary and ternary CsYxI(1 − x. We hope that this study will be helpful in designing binary and ternary Cs halides for optoelectronic applications.

  12. Synthesis, vibrational and optical properties of a new three-layered organic-inorganic perovskite (C4H9NH3)4Pb3I4Br6

    International Nuclear Information System (INIS)

    Dammak, T.; Elleuch, S.; Bougzhala, H.; Mlayah, A.; Chtourou, R.; Abid, Y.

    2009-01-01

    An organic-inorganic hybrid perovskite (C 4 H 9 NH 3 ) 4 Pb 3 I 4 Br 6 was synthesized and studied by X-ray diffraction, Raman and infrared spectroscopies, optical transmission and photoluminescence. The title compound, abbreviated (C 4 ) 4 Pb 3 I 4 Br 6 , crystallises in a periodic two-dimensional multilayer structure with P2 1 /a space group. The structure is built up from alternating inorganic and organic layers. Each inorganic layer consists of three sheets of PbX 6 (X=I, Br) octahedra. Raman and infrared spectra of the title compound were recorded in the 100-3500 and 400-4000 cm -1 frequency ranges, respectively. An assignment of the observed vibration modes is reported. Optical transmission measurements, performed on thin films of (C 4 ) 4 Pb 3 I 4 Br 6 , revealed two absorption bands at 474 and 508 nm. Photoluminescence measurements have shown a green emission peak at 519 nm.

  13. Formation of T-shaped versus charge-transfer molecular adducts in the reactions between bis(thiocarbonyl) donors and Br2 and I2.

    Science.gov (United States)

    Mancini, Annalisa; Aragoni, M Carla; Bricklebank, Neil; Castellano, Carlo; Demartin, Francesco; Isaia, Francesco; Lippolis, Vito; Pintus, Anna; Arca, Massimiliano

    2013-03-01

    The reactions of 4,5,6,7-tetrathiocino-[1,2-b:3,4-b']-1,3,8,10-tetrasubstituted-diimidazolyl-2,9-dithiones (R(2),R'(2)-todit; 1: R=R'=Et; 2: R=R'=Ph; 3: R=Et, R'=Ph) with Br(2) exclusively afforded 1:1 and 1:2 "T-shaped" adducts, as established by FT-Raman spectroscopy and single-crystal X-ray diffraction in the case of complex 1·2Br(2). On the other hand, the reactions of compounds 1-3 with molecular I(2) provided charge-transfer (CT) "spoke" adducts, among which the solvated species 3·2I(2)·(1-x)I(2)·xCH(2)Cl(2) (x=0.94) and (3)(2)·7I(2)·xCH(2)Cl(2), (x=0.66) were structurally characterized. The nature of all of the reaction products was elucidated based on elemental analysis and FT-Raman spectroscopy and supported by theoretical calculations at the DFT level. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Communication: Transfer Ionization in a Thermal Reaction of a Cation and Anion: Ar+ with Br and I (Postprint)

    Science.gov (United States)

    2016-01-29

    AFRL-RV-PS- AFRL-RV-PS- TP-2015-0016 TP-2015-0016 COMMUNICATION: TRANSFER IONIZATION IN A THERMAL REACTION OF A CATION AND ANION: AR+ WITH BR...DATES COVERED (From - To) 01 Jun 2013 – 23 Sep 2013 4. TITLE AND SUBTITLE Communication: Transfer Ionization in a Thermal Reaction of a Cation and Anion...Rights. Communication: Transfer ionization in a thermal reaction of a cation and anion: Ar+ with Br− and I− Nicholas S. Shuman, Thomas M. Miller

  15. Evaluation of the angular response of LaBr{sub 3}(Ce) and NaI(Tl) radiological identifiers for emergency situations attendance

    Energy Technology Data Exchange (ETDEWEB)

    Izidório, Ana C.A.C.; Cardoso, Domingos D’O.; Oliveira, Luciano S.R.; Balthar, Mario C.V.; Amorim, Aneuri S. de; Santos, Avelino dos; Guimarães Junior, Walter J.; Arbach, Mayara N., E-mail: carolizidorio@hotmail.com, E-mail: domingos.oliveiralvr71@gmail.com, E-mail: walter_guimaraes@ime.eb.br, E-mail: lucianosantarita@gmail.com, E-mail: mariobalthar@gmail.com, E-mail: aneurideamorim@gmail.com, E-mail: hiperav@gmail.com, E-mail: mayaraarbach@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Instituto de Defesa Química, Biológica, Radiológica e Nuclear (IDQBRN/CTEx), Barra de Guaratiba, RJ (Brazil); Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-11-01

    The Institute of Chemical, Biological, Radiological and Nuclear Defense (IDQBRN) of the Brazilian Army has been developing activities aimed at characterizing radiological detectors for use during emergency situations and radiological incidents and also for research and academic activities. This work describes the experiments performed in order to evaluate the angular response of LaBr{sub 3}(Ce) and NaI(Tl) portable radiological identifiers (PRI) with scintillator crystal detectors measuring 1.5” x 1.5” and 3.0” x 1.5”, respectively. A {sup 137}Cs source with corrected activity of 2.623 GBq (July 29, 2017) supplied the beam for the experiments. It was positioned at a distance of 1.00 m from the PRIs, together with attenuators, in order to yield different ambient dose equivalent rate, H⁎(10), thus allowing the adjustment of the counting statistics and the analysis of the responses obtained. The objective of this work was to evaluate the angular dependence of the response of LaBr{sub 3}(Ce) and NaI(Tl) PRIs exposed to a {sup 137}Cs source by azimuthally varying the angle of incidence of the primary beam within the 0° ± 30° range, measured from the center of the sensitive volume of the scintillators. The PRIs were programmed to reach a maximum count of 10{sup 6} in order to ensure that the relative uncertainty of the measured data would be negligible which led to improved angular response data, in addition to higher correlation factors and greater reliability in the responses obtained with LaBr{sub 3}(Ce) and NaI(T1) portable radiological identifiers. (author)

  16. NMR shielding and spin–rotation constants of {sup 175}LuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br, {sup 127}I) molecules

    Energy Technology Data Exchange (ETDEWEB)

    Demissie, Taye B. [Centre for Theoretical and Computational Chemistry Department of Chemistry, UiT – The Arctic University of Norway, N-9037 Tromsø (Norway)

    2015-12-31

    This presentation demonstrates the relativistic effects on the spin-rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants and shielding spans of {sup 175}LuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br, {sup 127}I) molecules. The results are obtained from calculations performed using density functional theory (non-relativistic and four-component relativistic) and coupled-cluster calculations. The spin-rotation constants are compared with available experimental values. In most of the molecules studied, relativistic effects make an order of magnitude difference on the NMR absolute shielding constants.

  17. Raman spectra of Pm2O3, PmF3, PmCl3, PmBr3 and PmI3

    International Nuclear Information System (INIS)

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

    1988-01-01

    Raman spectral data are presented for the sesquioxide and the trihalides (F, Cl, Br and I) of promethium. The Raman spectra of these lanthanide compounds are reported for the first time and are compared with those of the homologous lanthanide compounds. Tentative symmetry assignments have been made for the observed Raman-active bands based on factor group analysis of their respective crystal structures and comparisons with the assigned Raman spectra of other lanthanide compounds. The characteristic band patterns of the Raman phonon spectra have been found to be very useful in determining the crystal structure of the respective promethium compounds. (author)

  18. Comprehensive ab initio calculation and simulation on the low-lying electronic states of TlX (X = F, Cl, Br, I, and At).

    Science.gov (United States)

    Zou, Wenli; Liu, Wenjian

    2009-03-01

    The low-lying electronic states of TlX (X=F, Cl, Br, I, and At) are investigated using the configuration interaction based complete active space third-order perturbation theory [CASPT3(CI)] with spin-orbit coupling accounted for. The potential energy curves and the corresponding spectroscopic constants are reported. The results are grossly in good agreement with the available experimental data. The absorption spectra are simulated as well to reassign the experimental bands. The present results are also useful for guiding future experimental measurements.

  19. Laser microprobe analyses of Cl, Br, I, and K in fluid inclusions: Implications for sources of salinity in some ancient hydrothermal fluids

    Science.gov (United States)

    Böhlke, J.K.; Irwin, J.J.

    1992-01-01

    The relative concentrations of Cl, Br, I, and K in fluid inclusions in hydrothermal minerals were measured by laser microprobe noble gas mass spectrometry on irradiated samples containing 10−10 to 10−8 L of fluid. Distinctive halogen signatures indicate contrasting sources of fluid salinity in fluid inclusions from representative “magmatic” (St. Austell), “metamorphic” (Alleghany), and “geothermal” (Creede, Salton Sea) aqueous systems. Br/Cl mol ratios are lowest at Salton Sea (0.27–0.33 × 10−3), where high salinities are largely due to halite dissolution; intermediate at St. Austell (0.85 × 10−3), possibly representative of magmatic volatiles; and highest (near that of seawater) at Creede (1.5–2.1 × 10−3) and Alleghany (1.2–2.4 × 10−3), where dissolved halogens probably were leached from volcanic and (or) nonevaporitic sedimentary rocks. IC1">IC1 mol ratios are lowest (near that of seawater) at Creede (1–14 × 10−6), possibly because organisms scavenged I during low temperature recharge; intermediate at Salton Sea (24–26 × 10−6) and St. Austell (81× 10−6); and highest at Alleghany (320–940 × 10−6), probably because the fluids interacted with organic-rich sediments at high temperatures before being trapped. KCl">KCl mol ratios indicate disequilibrium with respect to hypothetical feldspathic alkali-Al-silicate mineral buffers at fluid inclusion trapping temperatures at Creede, and large contributions of (Na, K)-bicarbonate to total fluid ionic strength at Alleghany. Significant variations in Cl/Br/I/K ratios among different fluid inclusion types are correlated with previously documented mineralization stages at Creede, and with the apparent oxidation state of dissolved carbon at Alleghany. The new data indicate that Cl/ Br/I ratios in hydrothermal fluid inclusions vary by several orders of magnitude, as they do in modern surface and ground waters. This study demonstrates that halogen signatures of fluid inclusions

  20. Behaviour of I/Br/Cl-THMs and their projected toxicities under simulated cooking conditions: Effects of heating, table salt and residual chlorine

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Mingquan, E-mail: yanmq@pku.edu.cn; Li, Mingyang; Han, Xuze

    2016-08-15

    Highlights: • Additions of KI and KIO{sub 3}-fortified table salt cause I-THMs to increase. • CHCl{sub 2}I is the predominant I-THM formed in the presence of KIO{sub 3}-fortified table salt. • >90% of CHCl{sub 2}I is removed by heating, but concentrations of the other I-THMs increase. • Additions of KI or KIO{sub 3}-fortified salt increase the cytotoxicity due to I-THM formed. • Heating causes cytotoxicity to decrease for KIO{sub 3}-fortified salt but increase for KI. - Abstract: This study examined the effects of heating, residual chlorine and concentration of table salt on the generation of iodine-, bromine- and chlorine-containing trihalomethanes (THMs) under simulated cooking conditions. In the case of addition of either KI- or KIO{sub 3}-fortified salt, total I-THM concentrations increased with increasing iodine concentration, while total Cl/Br-THM concentrations decreased. CHCl{sub 2}I, CHBrClI, CHBrI{sub 2}, CHBr{sub 2}I and CHI{sub 3} were formed in the presence of KI salt, while only CHCl{sub 2}I was formed in the presence of KIO{sub 3} salt. CHCl{sub 2}I was unstable under cooking conditions, and >90% of this DBP was removed during heating, which in some cases increased the concentrations of the other I-THMs. The calculated cytotoxicity increased with addition of KI- or KIO{sub 3}-fortified salt due to the generation of I-THMs, whose impact on the cytotoxicity at room temperature was equal to or five times higher, respectively, than the cytotoxicity of the simultaneously formed Cl/Br-THMs for the cases of salts. Heating decreased the cytotoxicity, except for the case of addition of KI salt, in which the calculated cytotoxicity of I-THMs increased above 150% as the temperature was increased up to 100 °C. The reported results may have important implications for epidemiologic exposure assessments and, ultimately, for public health protection.

  1. A study of the atmospherically important reactions between dimethyl selenide (DMSe) and molecular halogens (X2 = Cl2, Br2, and I2) with ab initio calculations.

    Science.gov (United States)

    Rhyman, Lydia; Armata, Nerina; Ramasami, Ponnadurai; Dyke, John M

    2012-06-14

    The atmospherically relevant reactions between dimethyl selenide (DMSe) and the molecular halogens (X(2) = Cl(2), Br(2), and I(2)) have been studied with ab initio calculations at the MP2/aug-cc-pVDZ level of theory. Geometry optimization calculations showed that the reactions proceed from the reagents to the products (CH(3)SeCH(2)X + HX) via three minima, a van der Waals adduct (DMSe:X(2)), a covalently bound intermediate (DMSeX(2)), and a product-like complex (CH(3)SeCH(2)X:HX). The computed potential energy surfaces are used to predict what molecular species are likely to be observed in spectroscopic experiments such as gas-phase photoelectron spectroscopy and infrared matrix isolation spectroscopy. It is concluded that, for the reactions of DMSe with Cl(2) and Br(2), the covalent intermediate should be seen in spectroscopic experiments, whereas, in the DMSe + I(2) reaction, the van der Waals adduct DMSe:I(2) should be observed. Comparison is made with previous related calculations and experiments on dimethyl sulfide (DMS) with molecular halogens. The relevance of the results to atmospheric chemistry is discussed. The DMSeX(2) and DMSe:X(2) intermediates are likely to be reservoirs of molecular halogens in the atmosphere which will lead on photolysis to ozone depletion.

  2. Influence of exposure of pregnant rats to tritiated water (HTO) on swimming function and brain weight of their litters

    International Nuclear Information System (INIS)

    Yang Zhiyuan; Guo Yuefeng

    1986-01-01

    In order to understand the effects of HTO exposure on the development of central nervous system in rats, the influence of exposure of pregnant rat to HTO on the swimming ability of their litters was studies. Experiment was completed in 21 rats and their 237 litters. It was found that exposure of rats to HTO at activity of 0.185 MBq/ml of body water (5 μCi/ml) or 0.740 MBq/ml (20 μCi/ml), begining on the 8th day of gestation, may retard the development of swimming ability in young litters (up to 18 day of life). These findings indicate that exposure to HTO at lower doses (0.20-1.85 Gy) may resut in a retardation of the function of the development of central nervous system in rats

  3. Experimental determination of the kinetic conversion rate of gaseous tritium into HTO

    International Nuclear Information System (INIS)

    Gulden, W.; Guenot, J.; Djerassi, H.; Clerc, H.

    1986-09-01

    To assess the impact of atmospheric tritium releases from a fusion plant to the environment, the dose to man usually is determined under the conservative assumption that all tritium is released in the more dangerous oxide form. To quantify this overprediction, experiments are presently being performed by CEA. Oxidation of tritium gas by soil and subsequent resuspension of HTO from soil to atmosphere is one of them. First results have been obtained by CEA on the kinetics of HTO resuspension from contaminated soils. Immediately after contamination, the fraction of the deposited activity which is resuspended to atmosphere is in the range of 1% to 5% per hour. This resuspension rate then decreases more or less slowly with time, depending on specific conditions

  4. Cellular responses to tritium exposure in rainbow trout: HTO- and OBT-spiked feed exposure experiments

    Energy Technology Data Exchange (ETDEWEB)

    Festarini, A.; Shultz, C.; Stuart, M.; Kim, S.B., E-mail: amy.festarini@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Ferreri, C. [National Research Council of Italy, Dept. of Chemical Sciences and Materials Technologies, Bologna (Italy)

    2016-06-15

    Biological effects were evaluated in rainbow trout (Oncorhynchus mykiss) exposed to tritiated water (HTO) or food spiked with organically bound tritium (OBT). An HTO exposure study was conducted using a tritium activity concentration of 7000 Bq/L, and an OBT exposure study was conducted using a tritium activity concentration of 30 000 Bq/L. Following 140 days of in vivo HTO exposure, liver, heart, spleen, kidney, and brain cells did not show statistically significant differences in viability; kidney, liver, and spleen cells did not show significant differences in DNA double-strand break repair activity compared with control cells. Membrane fatty acid composition analysis was conducted on liver cells and no effects of HTO exposure could be detected. Following 140 days of in vivo OBT exposure, viability and DNA double-strand break repair activity were not statistically different from controls in liver, heart, spleen, kidney, and brain cells. Changes, however, were noted in the fatty acid composition of liver and muscle tissues. For both studies, all measurements were performed on each tissue and on a fraction of the same tissue that was exposed to a gamma 4 Gy dose in vitro to test for adaptive responses, and no effects were observed except for fatty acid composition. The findings demonstrated that membrane fatty acid composition is a sensitive marker and that microscopic evaluation of gamma-H2AX foci is more sensitive than the flow cytometric approach. These studies are the first to correlate uptake and depuration with biological health indicators in edible fish for tritium exposures within worldwide drinking water guidelines. (author)

  5. Cellular responses to tritium exposure in rainbow trout: HTO- and OBT-spiked feed exposure experiments

    International Nuclear Information System (INIS)

    Festarini, A.; Shultz, C.; Stuart, M.; Kim, S.B.; Ferreri, C.

    2016-01-01

    Biological effects were evaluated in rainbow trout (Oncorhynchus mykiss) exposed to tritiated water (HTO) or food spiked with organically bound tritium (OBT). An HTO exposure study was conducted using a tritium activity concentration of 7000 Bq/L, and an OBT exposure study was conducted using a tritium activity concentration of 30 000 Bq/L. Following 140 days of in vivo HTO exposure, liver, heart, spleen, kidney, and brain cells did not show statistically significant differences in viability; kidney, liver, and spleen cells did not show significant differences in DNA double-strand break repair activity compared with control cells. Membrane fatty acid composition analysis was conducted on liver cells and no effects of HTO exposure could be detected. Following 140 days of in vivo OBT exposure, viability and DNA double-strand break repair activity were not statistically different from controls in liver, heart, spleen, kidney, and brain cells. Changes, however, were noted in the fatty acid composition of liver and muscle tissues. For both studies, all measurements were performed on each tissue and on a fraction of the same tissue that was exposed to a gamma 4 Gy dose in vitro to test for adaptive responses, and no effects were observed except for fatty acid composition. The findings demonstrated that membrane fatty acid composition is a sensitive marker and that microscopic evaluation of gamma-H2AX foci is more sensitive than the flow cytometric approach. These studies are the first to correlate uptake and depuration with biological health indicators in edible fish for tritium exposures within worldwide drinking water guidelines. (author)

  6. CFD model development and data comparison for thermal-hydraulic analysis of HTO pilot scale reactor

    International Nuclear Information System (INIS)

    Kochan, R.J.; Oh, C.H.

    1995-09-01

    The DOE Hydrothermal Oxidation (HTO) program is validating computational methods for use in scaling up small HTO systems to production scale. As part of that effort, the computational fluid dynamics code FLUENT is being used to calculate the integrated fluid dynamics and chemical reactions in an HTO vessel reactor designed by MODAR, Inc. Previous validation of the code used data from a benchscale reactor. This reports presents the validation of the code using pilotscale (10 times greater throughput than benchscale) data. The model for the pilotscale reactor has been improved based upon the benchscale data by including better fluid thermal properties, a better solution algorithm, addition of external heat transfer, investigation of the effects of turbulent flow, and, although not built into the computer model, a technique for using the calculated adiabatic oxidation temperatures for selecting initial conditions. Thermal results from this model show very good agreement with the limited test data from MODAR Run 920. In addition to the reactor temperatures, flowfield details, including chemical reaction distribution, and simulated salt particle transport were obtained. This model will be very beneficial in designing and evaluating larger commercial scale units. The results of these calculations indicate that for model validation, more accurate boundary conditions need to be measured in future test runs

  7. An experimental study on the carcinogenic effect of tritiated water (HTO) in mice

    International Nuclear Information System (INIS)

    Yokoro, Kenjiro; Yamamoto, Osamu; Kamiya, Kenji; Fujii, Yoshiaki; Numoto, Michitaka; Kinomura, Aiko

    1986-01-01

    A large-scale study of the long-term carcinogenic effect of tritiated water (HTO) has been performed in mice. This is the interime report on the results as of May 8, 1986. A total of 391 seven-week-old (C57BL/6N x C3H/He) Fl mice were intraperitoneally given 1.0 Ci/0.2 ml of HTO (3.75, 7.5, 15, or 20 mCi/mouse), in either single or fractionated manner. The incidence of leukemia was approximately five times higher in the group receiving a fractionated administration of 20 mCi than that receiving the same amount in a single manner, as was the latent period shorter. The incidence of solid tumors, unlike leukemia, was evidently higher in the group receiving a single administration of 15 mCi than that receiving 3.75 mCi four times. The latent period also tended to be short in the former group. The groups with higher amounts of HTO had slightly higher incidence of multiple primaries. The ovary was the most common site of tumor. Expression of an oncogene, N-ras, was frequently observed in the case of leukemia, fibrosarcoma, and tumors of the thyroid, ovary, and lung. (Namekawa, K.)

  8. Cytogenetic adaptive response of mouse bone marrow cells to low level HTO

    International Nuclear Information System (INIS)

    Chen Deqing; Zhang Zhaoyang; Zhou Xiangyan

    1993-01-01

    Mice were abdominally injected with a adaptive dose of 3.7 x 10 2 -3.7 x 10 5 Bq/gbw HTO, and then exposed to a challenge dose of 1.5 Gy of 6 '0Co γ-rays. In bone marrow cells that received both the adaptive and challenge doses, the chromatid breaks are lower than expected on the basis of additivity of the effects of the individual treatment. The adaptive response induced with 3.7 x 10 3 Bq/gbw HTO is the most remarkable, but at 3.7 x 10 5 Bq/gbw the adaptive response seems to disappear. The adaptive response can be observed by exposing to 1.5 Gy γ-rays from 1 to 5 days after injection of 3.7 x 10 3 Bq/gbw HTO, which is the most obvious one to reduce chromatid breaks to 50% of expected at the 5th day, but at the 7th day to equate to expected. The frequency of chromatid breaks is gradually reduced with time after challenge dose, the maximum index number of adaptive response is 0.50 and appears at 24 hr after challenge dose

  9. Electronic structure calculations and optical properties of a new organic-inorganic luminescent perovskite: (C9H19NH3)2PbI2Br2

    International Nuclear Information System (INIS)

    Abid, H.; Samet, A.; Dammak, T.; Mlayah, A.; Hlil, E.K.; Abid, Y.

    2011-01-01

    (C 9 H 19 NH 3 ) 2 PbI 2 Br 2 compound is a new crystal belonging to the large hybrid organic-inorganic perovskites compounds family. Optical properties are investigated by optical absorption UV-visible and photoluminescence (PL) techniques. Bands to band absorption peak at 2.44 eV as well as an extremely strong yellow-green photoluminescence emission at 2.17 eV is observed at room temperature. First principle calculations based on the DFT and FLAPW methods combined with LDA approximation are performed as well. Density of state close to the gap is presented and discussed in terms of optical absorption and photoluminescence experimental results. The perfect agreement between experimental data and electronic structure calculations is highlighted. - Highlights: → (C 9 H 19 NH 3 ) 2 PbI 2 Br 2 compound is a new crystal with strong yellow-green PL emission at 2.17 eV. → Calculations based on DFT and FLAPW method combined with LDA approximation are performed. → Gap, optical transitions and exciton presence were predicted from density of states. → Agreement between experimental data and electronic structure calculations.

  10. Ternary rare-earth halides of the A2MX5 type (A = K, In, NH4, Rb, Cs; X = Cl, Br, I)

    International Nuclear Information System (INIS)

    Meyer, G.; Soose, J.; Moritz, A.; Vitt, V.; Holljes, T.

    1985-01-01

    Ternary rare-earth (=M) chlorides, bromides, and iodides In 2 MCl 5 , (NH 4 ) 2 MCl 5 , Rb 2 MCl 5 , Cs 2 MCl 5 , CsRbMCl 5 , K 2 MBr 5 , Rb 2 MBr 5 , K 2 MI 5 , and Rb 2 MI 5 have been synthesized. Single crystals of In 2 PrCl 5 , Rb 2 PrCl 5 , K 2 PrBr 5 , and K 2 PrI 5 were grown and the structures refined. The other halides were characterized by X-ray powder patterns. They are isotypic either with K 2 PrCl 5 (orthorhombic, Pnma, Z = 4, hexagonal arrangement of chains of edge-connected polyhedra [PrX 7 ]) or with Cs 2 DyCl 5 (orthorhombic, Pbnm, Z = 4, hexagonal arrangement of cis-corner-connected octahedra [DyCl 6 ]) which may be discriminated in structure field diagrams. The thermal expansion was investigated for Cs 2 LuCl 5 and Rb 2 PrX 5 (X = Cl, Br, I). (author)

  11. Using Halogens (Cl, Br, F, I) and Stable Isotopes of Water (δ18O, δ2H) to Trace Hydrological and Biogeochemical Processes in Prairie Wetlands

    Science.gov (United States)

    Levy, Z. F.; Lu, Z.; Mills, C. T.; Goldhaber, M. B.; Rosenberry, D. O.; Mushet, D.; Siegel, D. I.; Fiorentino, A. J., II; Gade, M.; Spradlin, J.

    2014-12-01

    Prairie pothole wetlands are ubiquitous features of the Great Plains of North America, and important habitat for amphibians and migratory birds. The salinity of proximal wetlands varies highly due to groundwater-glacial till interactions, which influence wetland biota and associated ecosystem functions. Here we use halogens and stable isotopes of water to fingerprint hydrological and biogeochemical controls on salt cycling in a prairie wetland complex. We surveyed surface, well, and pore waters from a groundwater recharge wetland (T8) and more saline closed (P1) and open (P8) basin discharge wetlands in the Cottonwood Lake Study Area (ND) in August/October 2013 and May 2014. Halogen concentrations varied over a broad range throughout the study area (Cl = 2.2 to 170 mg/L, Br = 13 to 2000 μg/L, F = evaporation-enriched pond water (δ18O = -9.5 to -2.71 ‰) mixes with shallow groundwater in the top 0.6 m of fringing wetland soils and 1.2 m of the substrate in the center of P1. Our results suggest endogenous sources for Br and I within the prairie landscape that may be controlled by biological mechanisms or weathering of shale from glacial till.

  12. Recent Progress in the Design of Advanced Cathode Materials and Battery Models for High-Performance Lithium-X (X = O2 , S, Se, Te, I2 , Br2 ) Batteries.

    Science.gov (United States)

    Xu, Jiantie; Ma, Jianmin; Fan, Qinghua; Guo, Shaojun; Dou, Shixue

    2017-07-01

    Recent advances and achievements in emerging Li-X (X = O 2 , S, Se, Te, I 2 , Br 2 ) batteries with promising cathode materials open up new opportunities for the development of high-performance lithium-ion battery alternatives. In this review, we focus on an overview of recent important progress in the design of advanced cathode materials and battery models for developing high-performance Li-X (X = O 2 , S, Se, Te, I 2 , Br 2 ) batteries. We start with a brief introduction to explain why Li-X batteries are important for future renewable energy devices. Then, we summarize the existing drawbacks, major progress and emerging challenges in the development of cathode materials for Li-O 2 (S) batteries. In terms of the emerging Li-X (Se, Te, I 2 , Br 2 ) batteries, we systematically summarize their advantages/disadvantages and recent progress. Specifically, we review the electrochemical performance of Li-Se (Te) batteries using carbonate-/ether-based electrolytes, made with different electrode fabrication techniques, and of Li-I 2 (Br 2 ) batteries with various cell designs (e.g., dual electrolyte, all-organic electrolyte, with/without cathode-flow mode, and fuel cell/solar cell integration). Finally, the perspective on and challenges for the development of cathode materials for the promising Li-X (X = O 2 , S, Se, Te, I 2 , Br 2 ) batteries is presented. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Study of ammonia dynamics in mixed crystals K1-x(NH4)xHal (Hal = Cl, Br, I) by the inelastic neutron scattering

    International Nuclear Information System (INIS)

    Natkanets, I.; Smirnov, L.S.; Solov'ev, A.I.; )

    1997-01-01

    The investigation of the dynamics of ammonium ion in the disordered α-phase of mixed crystals K 1-x (NH 4 ) x Hal (Hal = Cl, Br, I) is carried out by the inelastic incoherent neutron scattering (IINS) method. IINS spectra are measured in the 2-200 meV energy range and the 10-300 K temperature range by the time-of-flight method. The generalized densities of phonon states are defined in the single-phonon approximation. It is found out that the libration mode of ammonium ion has the weak concentration dependence. Resonant modes are observed at low temperature for all concentration range of the existence of the disordered α-phase. The broadening of resonant modes at the expensive of the jump rotation diffusion of ammonium ions takes place at temperature above 10 K [ru

  14. Trapping charges at grain boundaries and degradation of CH3NH3Pb(I1-x Br x )3 perovskite solar cells

    Science.gov (United States)

    Phuong Nguyen, Bich; Kim, Gee Yeong; Jo, William; Kim, Byeong Jo; Jung, Hyun Suk

    2017-08-01

    The electrical properties of CH3NH3Pb(I1-x Br x )3 (x = 0.13) perovskite materials were investigated under ambient conditions. The local work function and the local current were measured using Kelvin probe force microscopy and conductive atomic force microscopy, respectively. The degradation of the perovskite layers depends on their grain size. As the material degrades, an additional peak in the surface potential appears simultaneously with a sudden increase and subsequent relaxation of the local current. The potential bending at the grain boundaries and the intragrains is the most likely reason for the change of the local current surface of the perovskite layers. The improved understanding of the degradation mechanism garnered from this study helps pave the way toward an improved photo-conversion efficiency in perovskite solar cells.

  15. Novel germanetellones: XYGe=Te (X, Y = H, F, Cl, Br, I and CN) - structures and energetics. Comparison with the first synthetic successes.

    Science.gov (United States)

    Jaufeerally, Naziah B; Abdallah, Hassan H; Ramasami, Ponnadurai; Schaefer, Henry F

    2014-03-14

    No stable germanetellone was described until Tbt(Dis)Ge=Te and Tbt(Tip)Ge=Te (Tbt = 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl, Dis = bis(trimethylsilyl)methyl and Tip = 2,4,6-triisopropylphenyl) were reported in 1997. Following these initial experiments, there has arisen considerable interest in Ge[double bond, length as m-dash]Te systems. An obvious question is: why have the simple XYGe=Te (X, Y = H, F, Cl, Br, I and CN) molecules not yet been isolated? In view of the present situation, theoretical information may be of great help for further advances in germanetellone chemistry. A systematic investigation of the XYGe=Te molecules is carried out using the second order Møller-Plesset perturbation theory (MP2) and density functional theory (DFT). The structures and energetics, including ionization potentials (IPad and IPad(ZPVE)), four different forms of neutral-anion separations (EAad, EAad(ZPVE), VEA and VDE) and the singlet-triplet gaps, are reported. The electronegativity (χ) reactivity descriptor for the halogens (F, Cl, Br and I) and the natural charge separations of the Ge=Te moiety are used to assess the interrelated properties of germanetellone and its derivatives. The results are analyzed, discussed and compared with analogous studies of telluroformaldehyde, silanetellone and their derivatives. The thermodynamic viabilities of some of the novel germanetellones have also been evaluated in terms of the bond dissociation enthalpies of Tbt(Dis)Ge=Te and Tbt(Tip)Ge=Te. The simple mono-substituted germanetellones appear to be slightly more thermodynamically favored than Tbt(Dis)Ge=Te and Tbt(Tip)Ge=Te, since the bond dissociation enthalpies of these kinetically stabilized germanetellones are about 28 and 51 kcal mol(-1) lower, respectively.

  16. Organically bound tritium (OBT) formation in rainbow trout (Oncorhynchus mykiss): HTO and OBT-spiked food exposure experiments.

    Science.gov (United States)

    Kim, S B; Shultz, C; Stuart, M; McNamara, E; Festarini, A; Bureau, D P

    2013-02-01

    In order to determine the rate of organically bound tritium (OBT) formation, rainbow trout (Oncorhynchus mykiss) were exposed to tritiated water (HTO) or OBT-spiked food. The HTO (in water) exposure study was conducted using a tritium activity concentration of approximately 7000 Bq/L and the OBT (in food) exposure study was conducted using a tritium activity concentration of approximately 30,000 Bq/L. Fish in both studies were expected to be exposed to similar tritium levels assuming 25% incorporation of the tritiated amino acids found in the food. Four different sampling campaigns of HTO exposure (Day 10, 30, 70, 140) and five different sampling campaigns of OBT-spiked food exposure (Day 9, 30, 70, 100, 140) were conducted to measure HTO and OBT activity concentrations in fish tissues. OBT depuration was also evaluated over a period of 30 days following the 140 d exposure studies. The results suggested that the OBT formation rate was slower when the fish were exposed to HTO compared to when the fish were ingesting OBT. In addition, the results indicated that OBT can bioaccumulate in fish tissues following OBT-spiked food exposure. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  17. Measurement of HTO-HT in atmosphere using the Draeger (Drager) tube

    International Nuclear Information System (INIS)

    Huang, Z.; Harris, S.J.; Giorgio, P.R.

    1993-01-01

    It is clearly that, incorporation with the liquid scintillation counting, the Drager tube measuring system for Hydrogen allows the measurement of tritium contamination in atmosphere, e.g. HTO/HT (tritiated water vapour/tritium gas) simultaneously, at levels well below those derived air concentrations (DACs) prescribed by The International Commission on Radiological Protection (ICRP) and the UK Regulations. The novel tritium measuring system of Drager tube, in liquid phase or gel phase, can be used as a cheap, convenient and quick method of tritium detection

  18. Investigation of tritium transfer to plants via the OBT/HTO and OBT/TFWT ratios

    International Nuclear Information System (INIS)

    Boyer, C.; Guetat, P.; Vichot, L.; Losset, Y.; Boyer, C.; Fromm, M.; Mavon, C.; Boyer, C.; Tatin-Froux, F.; Badot, P.M.

    2009-01-01

    After having recalled some concepts used to distinguish the various forms of water present in plants, and the reactions in presence of tritium, the authors discuss the biochemical behaviour of tritium. Then, they briefly report a literature survey and, for different plants and crops, indicate the values of the OBT/HTO (organically bound tritium/tritiated water) and OBT/TFWT (organically bound tritium/tissue free water tritium) ratios. They also report experimental studies performed by exposures of lettuces at the vicinity of a nuclear installation

  19. NMR espectroscopic parameters of HX and Si (Sn)X4 (X = H, F, Cl, Br and I) and SnBr4−nIn model compounds

    International Nuclear Information System (INIS)

    Maldonado, Alejandro F.; Gimenez, Carlos A.; Aucar, Gustavo A.

    2012-01-01

    Graphical abstract: Optimized fully relativistic calculations of NMR J-couplings (HBr, HI), chemical shifts (Si, Sn) and absolute shielding for reference compounds of heavy atoms (Si, Sn) are given. Highlights: ► In this article we show a procedure to get accurate NMR σ Ref of Si and Sn. ► Calculations of σ on more than three heavy-atom-containing molecules are given. ► Our results are closer to δ exp than previous calculations for SnX 4 (X = H, Cl, Br, I). ► Optimized basis sets were considered for full R and NR calculations of NMR J and σ. ► Relativistic effects enlarge electron correlation effects on J-couplings. - Abstract: The NMR spectroscopic parameters are largely influenced by relativistic effects. They are highly dependent on the electronic behavior inside the spatial regions occupied by nuclei. Full relativistic calculations of indirect nuclear spin–spin couplings at random phase level of approach (RPA) in the title compounds with reoptimized Dyall cVTZ basis sets are given. A comparison with the results of calculations with other basis sets that are mostly used within the non-relativistic (NR) domain is presented. We analyzed the dependence of that couplings with the speed of light over the whole range of values, from the full relativistic to the NR regimes. Within this last regime, calculations at the second-order level of approach (SOPPA) indicated that electron correlation effects may not be as important for nuclear magnetic shieldings, but they must be included with care for J-coupling calculations. From these calculations, we determined that relativity enlarges the electron correlation effects of the J-couplings of HBr and HI. Because the results of nuclear magnetic shielding calculations within polarization propagators at the RPA level were reliable, we were able to show a new and easy procedure to obtain absolute nuclear magnetic shieldings on reference compounds for both Si and Sn nuclei: σ[Si (CH 3 ) 4 ] = 421.28 ± 29.33 ppm

  20. Absorption of water vapour in the falling film of water-(LiBr + LiI + LiNO{sub 3} + LiCl) in a vertical tube at air-cooling thermal conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bourouis, Mahmoud; Valles, Manel; Medrano, Marc; Coronas, Alberto [Centro de Innovacion Tecnologica en Revalorizacion Energetica y Refrigeracion, CREVER, Universitat Rovira i Virgili, Autovia de Salou, s/n, 43006, Tarragona (Spain)

    2005-05-01

    In air-cooled water-LiBr absorption chillers the working conditions in the absorber and condenser are shifted to higher temperatures and concentrations, thereby increasing the risk of crystallisation. To develop this technology, two main problems are to be addressed: the availability of new salt mixtures with wider range of solubility than water-LiBr, and advanced absorber configurations that enable to carry out simultaneously an appropriate absorption process and an effective air-cooling. One way of improving the solubility of LiBr aqueous solutions is to add other salts to create multicomponent salt solutions. The aqueous solution of the quaternary salt system (LiBr + LiI + LiNO{sub 3} + LiCl) presents favourable properties required for air-cooled absorption systems: less corrosive and crystallisation temperature about 35 K lower than that of water-LiBr.This paper presents an experimental study on the absorption of water vapour over a wavy laminar falling film of an aqueous solution of (LiBr + LiI + LiNO{sub 3} + LiCl) on the inner wall of a water-cooled smooth vertical tube. Cooling water temperatures in the range 30-45 C were selected to simulate air-cooling thermal conditions. The results are compared with those obtained in the same experimental set-up with water-LiBr solutions.The control variables for the experimental study were: absorber pressure, solution Reynolds number, solution concentration and cooling water temperature. The parameters considered to assess the absorber performance were: absorber thermal load, mass absorption flux, degree of subcooling of the solution leaving the absorber, and the falling film heat transfer coefficient.The higher solubility of the multicomponent salt solution makes possible the operation of the absorber at higher salt concentration than with the conventional working fluid water-LiBr. The absorption fluxes achieved with water-(LiBr + LiI + LiNO{sub 3} + LiCl) at a concentration of 64.2 wt% are around 60 % higher than

  1. Development of a reference method and sampling system for continuous monitoring of environmental HT and HTO concentration in the air

    International Nuclear Information System (INIS)

    Uchrin, G.

    1992-06-01

    A differential sampling system to monitor environmental Tritiated Water Vapour (HT) and Tritiated Hydrogen Gas (HTO) concentrations in the atmosphere was developed and tested. The sampler consists of an aerosol filter, diaphragm pump, absorption trap for HTO (molecular sieve), supply of H 2 carrier (electrolysis unit), conversion trap for HT (Pd-impregnated molecular sieve), flow meter and gas meter. The sampler operates with a flow rate between 30 and 80 1/h, with a typical sampling period of one week. Vacuum desorption at high temperature is used to extract the HTO collected in the absorption and conversion traps. Tritium analysis is carried out using liquid scintillation spectrometry or gas proportional counting. The sampler is equipped with built-in safety systems and can operate in remote places. Refs, figs and tabs

  2. Den enes död, den andres bröd : En fallstudie i Fonus kriskommunikation

    OpenAIRE

    Orest Flavet, Sebastian

    2014-01-01

    Denna studie undersöker hur begravningsbyrån Fonus valde att bemöta en kritisk artikel, publicerad i Aftonbladet, med ett pressmeddelande som lades upp på den egna hemsidan. Uppsatsen undersöker först vilka retoriska verktyg som har använts i skapandet av detta meddelande, och sett från Benoits teori om Image Repair, vilka strategier som använts och hur användningen av dessa har sett ut. Därefter söker studien att praktiskt undersöka detta budskap genom att låta en utvald grupp respondenter t...

  3. An overview of organically bound tritium experiments in plants following a short atmospheric HTO exposure.

    Science.gov (United States)

    Galeriu, D; Melintescu, A; Strack, S; Atarashi-Andoh, M; Kim, S B

    2013-04-01

    The need for a less conservative, but reliable risk assessment of accidental tritium releases is emphasized in the present debate on the nuclear energy future. The development of a standard conceptual model for accidental tritium releases must be based on the process level analysis and the appropriate experimental database. Tritium transfer from atmosphere to plants and the subsequent conversion into organically bound tritium (OBT) strongly depends on the plant characteristics, seasons, and meteorological conditions, which have a large variability. The present study presents an overview of the relevant experimental data for the short term exposure, including the unpublished information, also. Plenty of experimental data is provided for wheat, rice, and soybean and some for potato, bean, cherry tomato, radish, cabbage, and tangerine as well. Tritiated water (HTO) uptake by plants during the daytime and nighttime has an important role in further OBT synthesis. OBT formation in crops depends on the development stage, length, and condition of exposure. OBT translocation to the edible plant parts differs between the crops analyzed. OBT formation during the nighttime is comparable with that during the daytime. The present study is a preliminary step for the development of a robust model of crop contamination after an HTO accidental release. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. 'Around here I am the law!'<br> Strengthening police officers' compliance with the rule of law in Costa Rica

    Directory of Open Access Journals (Sweden)

    Quirine A.M. Eijkman

    2006-12-01

    Full Text Available At the end of the last decade many Latin American states initiated public security reform. This included police human rights strategies, which aim to improve police officers' compliance with human rights. Particular strategies emphasized the development of police legal expertise. In Costa Rica this was done through professionalizing police legal training and police legal assistance within the preventive police. Yet the implementation of police human rights strategies is influenced by a wider socio-political and institutional context. 'Around here I am the law' reflects the process of transforming non-professionally trained police officers into professionally trained public officials whose core business is the enforcement of the law. On the basis of empirical research conducted in San José, this paper discusses the effect of implementing police human rights strategies that focus on improving police officers' compliance with the rule of law.

  5. Strong room-temperature ultraviolet to red excitons from inorganic organic-layered perovskites, (MX4 (M=Pb, Sn, Hg; X=I-, Br-)

    Science.gov (United States)

    Ahmad, Shahab; Prakash, G. Vijaya

    2014-01-01

    Many varieties of layered inorganic-organic (IO) perovskite of type (MX4 (where R: organic moiety, M: divalent metal, and X: halogen) were successfully fabricated and characterized. X-ray diffraction data suggest that these inorganic and organic structures are alternatively stacked up along c-axis, where inorganic mono layers are of extended corner-shared MX6 octahedra and organic spacers are the bi-layers of organic entities. These layered perovskites show unusual room-temperature exciton absorption and photoluminescence due to the quantum and dielectric confinement-induced enhancement in the exciton binding energies. A wide spectral range of optical exciton tunability (350 to 600 nm) was observed experimentally from systematic compositional variation in (i) divalent metal ions (M=Pb, Sn, Hg), (ii) halides (X=I and Br-), and (iii) organic moieties (R). Specific photoluminescence features are due to the structure of the extended MX42- network and the eventual electronic band structure. The compositionally dependent photoluminescence of these IO hybrids could be useful in various photonic and optoelectronic devices.

  6. Studies in uptake and turnover of tritiated water vapour (HTO) by vegetables. Untersuchungen zur Aufnahme und zum Umsatz von tritiiertem Wasserdampf (HTO) in Gemuesepflanzen

    Energy Technology Data Exchange (ETDEWEB)

    Roller, M.

    1989-02-01

    The aerial parts of vegetables were exposed to tritiated water vapour for up to three days in a plant growth chamber. The species used were Raphanus sativus L., Phaseolus vulgaris K. and Daucus carota L. (red radish, bean and carrot). The increase of specific activity of tissue free water as collected by freeze drying which was observed in the aerial parts of plants is explained by direct uptake of tritiated water vapour by the exposed part of the plant. It shows different characteristics for the several organs. No translocation of water from the laminae into other parts of the plant was observed. After combustion of dry matter tritium activity was detectable in the oxidation water for all parts of the plants. Kinetics of the specific activity of organically bound tritium in leaves can be described by a single curve. The lower - steep - part of the curve is increasing approximately with the uptake rate of HTO; this is explained by reversible binding of tritium by isotopic exchange reactions. The upper - flat - part of the curve represents tritium bound by light dependent reducing reactions of photosynthesis; it is increasing with a rate similar to the growth rate of leaves. (orig./KG).

  7. Comparison of hydrogen isotope exchange reactions between HTO vapor and the sodium salts of o-, m-, and p-aminobenzoic acid

    International Nuclear Information System (INIS)

    Okada, Minoru; Imaizumi, Hiroshi; Itoh, Tomoko

    1991-01-01

    Hydrogen isotope exchange reaction between HTO vapor and one of the sodium salts of o-, m-, and p-aminobenzoic acid (solid) was observed at 50 ∼ 80 degC. The acidity (acidity based on kinetic logic) for the materials at each temperature has been obtained with the A''-McKay plots based on the respective data obtained. The followings have been clarified by comparing these acidities (and the acidities obtained previously). 1) The acidity of aromatic amines can be expressed in terms of the acidity based on kinetic logic. 2) The reactivity of aromatic amine is strongly affected by both I-effect and R-effect. 3) It can be deduced that aromatic amines are more reactive than aliphatic amines. (author)

  8. Revealing critical mechanisms of BR-mediated apple nursery tree growth using iTRAQ-based proteomic analysis.

    Science.gov (United States)

    Zheng, Liwei; Ma, Juanjuan; Zhang, Lizhi; Gao, Cai; Zhang, Dong; Zhao, Caiping; Han, Mingyu

    2018-02-20

    Brassinosteroid is identified as an important hormone. However, information about brassinosteroid has not been fully elucidated, and few studies concerned its role in apple. The aim of this work was to study the role of brassinosteroid for apple tree growth. In our study, the effect of brassinosteroid on apple nursery tree was analyzed. The biomass, cell size and xylem content of apple nursery tree were obviously evaluated by brassinosteroid treatment; mineral elements contents, photosynthesis indexes, carbohydrate level and hormone contents were significantly high in brassinosteroid treated trees. To explore the molecular mechanisms of these phenotypic differences, iTRAQ-based quantitative proteomics were used to identify the expression profiles of proteins in apple nursery tree shoot tips in response to brassinosteroid at a key period (14days after brassinosteroid treatment). A total of 175 differentially expressed proteins were identified. They were mainly involved in chlorophyII biosynthesis, photosynthesis, carbohydrate metabolism, glycolysis, citric acid cycle, respiratory action, hormone signal, cell growth and ligin metabolism. The findings in this study indicate that brassinosteroid mediating apple nursery tree growth may be mainly through energy metabolism. Important biological processes identified here can be useful theoretical basis and provide new insights into the molecular mechanisms of brassinosteroid. Brassinosteroid is very important for plant growth and development. However, the molecular mechanism of brassinosteroid mediating growth process is not perfectly clear in plant, especially in apple nursery tree. We used a combination of physiological and bioinformatics analysis to investigate the effects of brassinosteroid on apple nursery tree growth and development. The data reported here demonstrated that brassinosteroid regulates apple nursery tree growth mainly through energy metabolism. Therefore it can provide a theoretical basis from energy

  9. NQR and X-ray crystal structure studies of cadmium halide complexes: [C(NH2)3]CdI3 and [4-ClC6H5NH3]3CdBr5

    International Nuclear Information System (INIS)

    Gesing, Thorsten M.; Lork, Enno; Terao, Hiromitsu; Ishihara, Hideta

    2016-01-01

    The crystal structures of [C(NH 2 ) 3 ]CdI 3 (1) and [4-ClC 6 H 5 NH 3 ] 3 CdBr 5 (2) have been determined at 100 K: monoclinic, Cc, a = 828.75(3) pm, b = 1615.31(5) pm, c = 810.64(3) pm, and β = 106.5820(10) for 1; monoclinic, P2 1 /c, a = 1486.93(5) pm, b = 794.31(3) pm, c = 2290.59(7) pm, and β = 99.6830(10) for 2. The structure of 1 has an infinite chain of anions consisting of [CdI 4 ] tetrahedra sharing two corners. The structure of 2 has an infinite chain of anions consisting of [CdBr 6 ] octahedra sharing two corners in cis positions. In both structures, isolated cations are connected to the anion chains through weak hydrogen bonds Cd-X..H to result in three-dimensional network structures. In accordance with the crystal structures, three 127 I (m = ±1/2 <-> m = ±3/2), five 81 Br, and three 35 Cl nuclear quadrupole resonance (NQR) lines were observed for 1 and 2. The NQR spectra reflect the anion chain structures and their weak hydrogen bonds. The MO calculations of the models [Cd 5 I 16 ] 6- for 1 and [Cd 3 Br 16 ] 10- for 2 estimate only about half the values for the NQR frequencies but give accurate electric field gradient directions.

  10. Differences in the behaviour of HTO and H2O in soil after condensation from the atmosphere and conversion of HT to HTO and OBT in soil relative to moisture content and pore volume

    International Nuclear Information System (INIS)

    Bunnenberg, C.; Feinhals, J.; Wiener, B.

    1986-01-01

    Theoretical considerations and field and soil column experiments have identified the condensation of atmospheric water vapour as an additional process in the HTO contamination of soils. In contrast to wash-out, where tritium concentrations of the deposited water are the same as in the falling drops, the specific activity of the condensed water is increased compared with that of the atmospheric humidity, when the partial vapour pressure gradient of HTO between atmosphere and soil is higher than the H 2 O pressure gradient. With respect to HTO deposition, condensation may therefore be more effective per unit precipitation than wash-out. Experiments on the conversion rates of HT to HTO and OBT in soils have exhibited a pronounced dependence on moisture content and free pore volume. With rising moisture content, conversion increases due to enhanced bacterial action; while close to field capacity a decrease occurs as a result of restricted HT diffusion through the soil pores. In short-term experiments about 0.1% of the converted HT was found in the OBT form. (author)

  11. Importance of root HTO uptake in controlling land-surface tritium dynamics after an-acute HT deposition: a numerical experiment

    International Nuclear Information System (INIS)

    Ota, Masakazu; Nagai, Haruyasu; Koarashi, Jun

    2012-01-01

    To investigate the role of belowground root uptake of tritiated water (HTO) in controlling land-surface tritium (T) dynamics, a sophisticated numerical model predicting tritium behavior in an atmosphere-vegetation-soil system was developed, and numerical experiments were conducted using the model. The developed model covered physical tritiated hydrogen (HT) transport in a multilayered atmosphere and soil, as well as microbial oxidation of HT to HTO in the soil, and it was incorporated into a well-established HTO-transfer organically bound tritium (OBT)-formation model. The model performance was tested through the simulation of an existing HT-release experiment. Numerical experiments involving a hypothetical acute HT exposure to a grassland field with a range of rooting depths showed that the HTO release from the leaves to the atmosphere, driven by the root uptake of the deposited HTO, can exceed the HTO evaporation from the ground surface to the atmosphere when root water absorption preferentially occurs beneath the ground surface. Such enhanced soil-leaf-atmosphere HTO transport, caused by the enhanced root HTO uptake, increased HTO concentrations in both the surface atmosphere and in the cellular water of the leaf. Consequently, leaf OBT assimilation calculated for shallow rooting depths increased by nearly an order of magnitude compared to that for large rooting depths. - Highlights: ► A model that calculates HT deposition from atmosphere to soil was developed. ► Tritium dynamics after an-acute HT deposition was studied by numerical experiments. ► OBT formation highly depends on magnitude of uptake of the deposited HTO by roots.

  12. Partial structures in molten AgBr

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Hiroki [Department of Condensed Matter Chemistry and Physics, Faculty of Sciences, Kyushu University, 4-2-1 Ropponmatsu, Chuo-ku, Fukuoka 810-8560 (Japan)], E-mail: ueno@gemini.rc.kyushu-u.ac.jp; Tahara, Shuta [Faculty of Pharmacy, Niigata University of Pharmacy and Applied Life Science, Higashijima, Akiha-ku, Niigata 956-8603 (Japan); Kawakita, Yukinobu [Department of Physics, Faculty of Sciences, Kyushu University, 4-2-1 Ropponmatsu, Chuo-ku, Fukuoka 810-8560 (Japan); Kohara, Shinji [Research and Utilization Division, Japan Synchrotron Radiation Research Institute (JASRI, SPring-8), 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Takeda, Shin' ichi [Department of Physics, Faculty of Sciences, Kyushu University, 4-2-1 Ropponmatsu, Chuo-ku, Fukuoka 810-8560 (Japan)

    2009-02-21

    The structure of molten AgBr has been studied by means of neutron and X-ray diffractions with the aid of structural modeling. It is confirmed that the Ag-Ag correlation has a small but well-defined first peak in the partial pair distribution function whose tail penetrates into the Ag-Br nearest neighbor distribution. This feature on the Ag-Ag correlation is intermediate between that of molten AgCl (non-superionic melt) and that of molten AgI (superionic melt). The analysis of Br-Ag-Br bond angle reveals that molten AgBr preserves a rocksalt type local ordering in the solid phase, suggesting that molten AgBr is clarified as non-superionic melt like molten AgCl.

  13. BiOCl{sub x}Br{sub y}I{sub z} (x + y + z = 1) solid solutions with controllable band gap and highly enhanced visible light photocatalytic performances

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xiuguo; Zhang, Yangyang; Li, Chunmei; Zhang, Zhifeng; Peng, Zheng; Si, Huayan; Zhang, Jianmin [School of Materials Science and Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Li, Yanting, E-mail: yantingcn@stdu.edu.cn [School of Materials Science and Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Hebei Provincial Key Laboratory of Traffic Engineering materials, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China)

    2015-07-25

    Highlights: • BiOCl{sub x}Br{sub y}I{sub z} solid solutions were prepared by hydrolysis method. • Band gap of the solid solutions can be controllable by adjusting the molar ratio of halogen ions. • The samples show higher visible light photocatalytic activity than pure BiOX. • Orbital diversification of VB is beneficial to separating the holes and electrons effectively. • The mechanisms are discussed by active species trapping and band theory. - Abstract: A series of BiOCl{sub x}Br{sub y}I{sub z} solid solutions with controllable band gap and highly enhanced visible light photocatalytic performances were synthesized by a simple hydrolysis method. The samples were characterized by X-ray powder diffraction, UV–vis diffuse reflectance spectra, scanning electron microscope, high-resolution transmission electron microscopy and Brunauer–Emmett–Teller analysis. By adjusting the molar ratio of halogen ions, the band gap of BiOCl{sub x}Br{sub y}I{sub z} could be controllable to the suitable value for a photocatalytic reaction. Especially, BiOCl{sub x}Br{sub y}I{sub z} with a 1:1:2 molar ratio of Cl, Br to I showed the highest visible light photocatalytic activity for the degradation of methyl orange than individual BiOX systems. The degradation efficiency could reach over 90% within 60 min. The possible mechanism of photogenerated carrier transfer and higher photocatalytic activity was analyzed by active species trapping and energy band theory.

  14. First-principles study of electronic and optical properties of lead-free double perovskites Cs2NaBX6 (B = Sb, Bi; X = Cl, Br, I)

    Science.gov (United States)

    Zhao, Shuai; Yamamoto, Kumiko; Iikubo, Satoshi; Hayase, Shuzi; Ma, Tingli

    2018-06-01

    Organolead halide perovskite is regarded as the most promising light-harvesting material for next-generation solar cells; however, the intrinsic instability and toxicity of lead are still of great concern. Bismuth is ecofriendly and has electronic properties similar to those of lead, which has gradually attracted interest for optoelectronic applications. However, the valence state of bismuth is different from that of lead, eliminating the possibility of replacing lead by bismuth in organolead halide perovskites. To address this matter, one feasible strategy is to construct B-site double perovskites by the combination of Bi3+ and B+ in 1:1 ratio. In this work, lead-free halide double perovskites of the form Cs2NaBX6 (B = Sb, Bi; X = Cl, Br, I) were investigated by first-principles calculations. The electronic properties, optical absorption coefficients, and thermodynamic stability of these compounds were investigated to ascertain their potential application in solar energy conversion. The results provide theoretical support for the exploration of lead-free perovskite materials in potential optoelectronic applications.

  15. Recognition of a novel type X═N-Hal···Hal (X = C, S, P; Hal = F, Cl, Br, I) halogen bonding.

    Science.gov (United States)

    Gushchin, Pavel V; Kuznetsov, Maxim L; Haukka, Matti; Kukushkin, Vadim Yu

    2013-04-04

    The chlorination of the eight-membered platinum(II) chelates [PtCl2{NH═C(NR2)N(Ph)C(═NH)N(Ph)C(NR2)═NH}] (R = Me (1); R2 = (CH2)5 (2)) with uncomplexed imino group with Cl2 gives complexes bearing the ═N-Cl moiety [PtCl4{NH═C(NR2)N(Ph)C(═NCl)N(Ph)C(NR2)═NH}] (R = Me (3); R2 = (CH2)5 (4)). X-ray study for 3 revealed a novel type intermolecular halogen bonding ═N-Cl···Cl(-), formed between the Cl atom of the chlorinated imine and the chloride bound to the platinum(IV) center. The processing relevant structural data retrieved from the Cambridge Structural Database (CSDB) shows that this type of halogen bonding is realized in 18 more molecular species having X═N-Hal moieties (X = C, P, S, V, W; Hal = Cl, Br, I), but this weak ═N-Hal···Hal(-) bonding was totally neglected in the previous works. The presence of the halogen bonding in 3 was confirmed by theoretical calculations at the density functional theory (DFT, M06-2X) level, and its nature was analyzed.

  16. A Study of Acid-Base Equilibria in Acetonitrile Systems of 2-Halo(Cl,Br,I-4-nitropicoline(3,5,6 N-oxides

    Directory of Open Access Journals (Sweden)

    Lech Chmurzynski

    1999-03-01

    Full Text Available An attempt has been made to determine potentiometrically (1 acid dissociation constants of cations obtained by protonation of nine trisubstituted pyridine N-oxides, namely 2-halo(Cl, Br and I-4-nitropicoline N-oxides with the methyl group at positions 3, 5, and 6, as well as (2 the cationic homoconjugation constants of these cationic acids with conjugated N-oxides in acetonitrile. On the basis of the substitution effect, variations of the acid dissociation constants of the trisubstituted pyridine N-oxide cations are discussed. The determined pKa values of the protonated 2-halo-4-nitropicoline N-oxides are compared with the previously determined equilibrium constants of the cationic acids conjugated with the mono- and disubstituted pyridine N-oxides in acetonitrile. Further, based on the pKa values of the protonated 2-halo-4-nitropicoline N-oxides in acetonitrile, supplemented with correlations between pKa’s of the protonated mono- and disubstituted pyridine N-oxides in acetonitrile and water, the pKa's of the acids conjugated with the trisubstituted N-oxides studied in aqueous solutions have been estimated. Moreover, it has been concluded that the cationic homoconjugation constants cannot be determined by potentiometric titration in acetonitrile solutions of the 2-halo-4-nitropicoline N-oxide systems.

  17. Neutron Activation Resonance Integrals of 74Se, 78Se, 80Se, 81Br, 127I, 130Te, 138Ba, 140Ce, and 142Ce

    International Nuclear Information System (INIS)

    Ricabarra, M. D.; Turjanskl, R.; Ricabarra, G. H.; Bigham, C.B.

    1968-01-01

    A lithium-drift germanium γ-ray spectrometer has been used to make accurate intercomparisons of the ratio of resonance-integral to thermal-activation cross section by measuring cadmium ratios or relative activation rates in two different neutron spectra. The standard, gold, or secondary standard, indium, was mixed uniformly in the samples and the activities resolved with the spectrometer. Expressed as Westcott S 0 values, the results relative to S 0 = 17.7 for gold were as follows: 74 Se = 10.3 +± 0.1, 78 Se = 12.3 ± 0.3, 80 Sc = 2.65 ± 0.02, 81 Br = 24.3 ± 0.5, 127 I = 27.8 ± 0.5, 130 Te = 2.10 ± 0.07, 138 Ba = 0.649 ± 0.004, 140 Ce = 0.476 ± 0.003, 142 Ce = 0.865 ± 0.005. (author)

  18. Synthesis and characterization of novel plasmonic Ag/AgX-CNTs (X = Cl, Br, I) nanocomposite photocatalysts and synergetic degradation of organic pollutant under visible light.

    Science.gov (United States)

    Shi, Huixian; Chen, Jiangyao; Li, Guiying; Nie, Xin; Zhao, Huijun; Wong, Po-Keung; An, Taicheng

    2013-08-14

    A series of novel well-defined Ag/AgX (X = Cl, Br, I) loaded carbon nanotubes (CNTs) composite photocatalysts (Ag/AgX-CNTs) were fabricated for the first time via a facile ultrasonic assistant deposition-precipitation method at the room temperature (25 ± 1 °C). X-ray diffraction, X-ray photoelectron spectroscopy, nitrogen adsorption-desorption analysis, scanning electron microscopy, and ultraviolet-visible light absorption spectra analysis were used to characterize the structure, morphology, and optical properties of the as-prepared photocatalysts. Results confirmed the existence of the direct interfacial contact between Ag/AgX nanoparticles and CNTs, and Ag/AgX-CNTs nanocomposites exhibit superior absorbance in the visible light (VL) region owing to the surface plasmon resonance (SPR) of Ag nanoparticles. The fabricated composite photocatalysts were employed to remove 2,4,6-tribromophenol (TBP) in aqueous phase. A remarkably enhanced VL photocatalytic degradation efficiency of Ag/AgX-CNTs nanocomposites was observed when compared to that of pure AgX or CNTs. The photocatalytic activity enhancement of Ag/AgX-CNTs was due to the effective electron transfer from photoexcited AgX and plasmon-excited Ag(0) nanoparticles to CNTs. This can effectively decrease the recombination of electron-hole pairs, lead to a prolonged lifetime of the photoholes that promotes the degradation efficiency.

  19. Mechanical properties of hybrid organic-inorganic CH3NH3BX3 (B = Sn, Pb; X = Br, I perovskites for solar cell absorbers

    Directory of Open Access Journals (Sweden)

    Jing Feng

    2014-08-01

    Full Text Available The crystal structures, elastic and anisotropic properties of CH3NH3BX3 (B = Sn, Pb; X = Br, I compounds as solar cell absorber layers are investigated by the first-principles calculations. The type and strength of chemical bond B-X are found to determine the elastic properties. B-X bonds and the organic cations are therefore crucial to the functionalities of such absorbers. The bulk, shear, Young's modulus ranges from 12 to 30 GPa, 3 to 12 GPa, and 15 to 37 GPa, respectively. Moreover, the interaction among organic and inorganic ions would have negligible effect for elastic properties. The B/G and Poisson's ratio show it would have a good ductile ability for extensive deformation as a flexible/stretchable layer on the polymer substrate. The main reason is attributed to the low shear modulus of such perovskites. The anisotropic indices AU, AB AG, A1, A2, and A3 show ABX3 perovskite have very strong anisotropy derived from the elastic constants, chemical bonds, and symmetry.

  20. Pre-operational HTO/HT surveys in the vicinity of the Chalk River Laboratories tritium extraction plant

    International Nuclear Information System (INIS)

    Workman, W.J.G.; Brown, R.M.

    1993-08-01

    Surveys of the concentrations of HT and HTO in the atmosphere downwind of the Chalk River Laboratories reactor facilities were carried out in 1986 November, and in 1989 March, April and September under different conditions of air temperature, wind direction, and snow or vegetative cover. HT usually amounted to 1-5% of total tritium, but values up to 20% were observed, probably resulting from preferential removal of HTO. In all of the surveys, the greater persistence in the atmosphere of HT than of HTO was evident. The existing levels of HT are such that they will not be augmented significantly by chronic releases from the Tritium Extraction Plant (TEP) when it comes into operation. Hence, operation of the TEP will not facilitate studies of the environmental behaviour of chronically released HT. However, longer term studies of the distribution of HT from the existing facilities would be worthwhile. Soil and vegetation HTO levels in the study area are reported. Further studies of the distribution of tritium between the air, soil and vegetation in areas subjected to chronic exposure would be valuable

  1. Hurtigste versus mest brændstoføkonomiske ruter

    DEFF Research Database (Denmark)

    Andersen, Ove; Krogh, Benjamin Bjerre; Lahrmann, Harry

    2013-01-01

    Der er stort fokus på at forbedre brændstoføkonomien i transportbranchen generelt. I denne artikel anvendes brændstoftallene fra Controller Area Network Bus (CANBus) kombineret med GPS data til at skabe et digitalt vejkort, hvor det er muligt at sammenligne de hurtigste ruter med de mest brændsto...

  2. Cs 1–<i>x> Rb <i>x> PbCl 3 and Cs 1–<i>x> Rb <i>x> PbBr 3 Solid Solutions: Understanding Octahedral Tilting in Lead Halide Perovskites

    Energy Technology Data Exchange (ETDEWEB)

    Linaburg, Matthew R.; McClure, Eric T.; Majher, Jackson D.; Woodward, Patrick M.

    2017-04-03

    The structures of the lead halide perovskites CsPbCl3 and CsPbBr3 have been determined from X-ray powder diffraction data to be orthorhombic with Pnma space group symmetry. Their structures are distorted from the cubic structure of their hybrid analogs, CH3NH3PbX3 (X = Cl, Br), by tilts of the octahedra (Glazer tilt system a–b+a–). Substitution of the smaller Rb+ for Cs+ increases the octahedral tilting distortion and eventually destabilizes the perovskite structure altogether. To understand this behavior, bond valence parameters appropriate for use in chloride and bromide perovskites have been determined for Cs+, Rb+, and Pb2+. As the tolerance factor decreases, the band gap increases, by 0.15 eV in Cs1–xRbxPbCl3 and 0.20 eV in Cs1–xRbxPbBr3, upon going from x = 0 to x = 0.6. The band gap shows a linear dependence on tolerance factor, particularly for the Cs1–xRbxPbBr3 system. Comparison with the cubic perovskites CH3NH3PbCl3 and CH3NH3PbBr3 shows that the band gaps of the methylammonium perovskites are anomalously large for APbX3 perovskites with a cubic structure. This comparison suggests that the local symmetry of CH3NH3PbCl3 and CH3NH3PbBr3 deviate significantly from the cubic symmetry of the average structure.

  3. A study on the redox, spectroscopic, and photophysical characteristics of a series of octahedral hexamolybdenum(ii) clusters: [{Mo6X8}Y6]2- (X, Y = Cl, Br, or I).

    Science.gov (United States)

    Akagi, Soichiro; Fujii, Sho; Kitamura, Noboru

    2018-01-23

    We report a systematic study on the redox, spectroscopic, and photophysical properties of a series of [{Mo 6 X 8 }Y 6 ] 2- (X, Y = Cl, Br, or I. 1-9). All of the [{Mo 6 X 8 }Y 6 ] 2- clusters show intense and long-lived phosphorescence in both CH 3 CN and crystalline phases at 298 K. We found that the emission quantum yields (Φ em ) of 1-9 increase in the sequences X = Cl Br Br Br < Cl for given {Mo 6 X 8 } 4+ -core clusters. The present data demonstrate that arbitrary combinations of X and Y in [{Mo 6 X 8 }Y 6 ] 2- could tune τ em and Φ em in the ranges of 85-300 μs and 0.09-0.47, respectively. Both capping (X) and terminal ligand (Y) effects on the photophysical properties of the clusters are discussed on the basis of the energy gap (i.e., emission energy) dependence of the nonradiative decay rate constant.

  4. Reactor BR2

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2000-07-01

    The BR2 reactor is still SCK-CEN's most important nuclear facility. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. Various aspects concerning the operation of the BR2 Reactor, the utilisation of the CALLISTO loop and the irradiation programme, the BR2 R and D programme and the production of isotopes and of NTD-silicon are discussed. Progress and achievements in 1999 are reported.

  5. Reactor BR2

    International Nuclear Information System (INIS)

    Gubel, P.

    2000-01-01

    The BR2 reactor is still SCK-CEN's most important nuclear facility. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. Various aspects concerning the operation of the BR2 Reactor, the utilisation of the CALLISTO loop and the irradiation programme, the BR2 R and D programme and the production of isotopes and of NTD-silicon are discussed. Progress and achievements in 1999 are reported

  6. Role of the chemical substitution on the structural and luminescence properties of the mixed halide perovskite thin MAPbI{sub 3−x}Br{sub x} (0 ≤ x ≤ 1) films

    Energy Technology Data Exchange (ETDEWEB)

    Atourki, Lahoucine, E-mail: lahoucine.atourki@edu.uiz.ac.ma [Materials and Renewable Energy Laboratory, Faculty of Science, Ibn Zohr University, Agadir (Morocco); Vega, Erika; Marí, Bernabé; Mollar, Miguel [Instituto de Diseño y Fabricación (IDF), Universitat Politécnica de València, València (Spain); Ait Ahsaine, Hassan [Laboratoire Matériaux et environnement LME, Faculté des Sciences d' Agadir, Université Ibn Zohr, Agadir (Morocco); Bouabid, Khalid; Ihlal, Ahmed [Materials and Renewable Energy Laboratory, Faculty of Science, Ibn Zohr University, Agadir (Morocco)

    2016-05-15

    Highlights: • X-ray diffraction analyses indicate the formation of a tetragonal phase I4/mcm up to x = 0.4 and a cubic perovskite with space group Pm3 m across in the composition range of 0.6 ≤ x ≤ 1. • Perovskite films exhibit a very high absorbance in the visible and short infrared. • As the fraction of bromide change, the adsorption edge of thin film perovskite can be tuned along the visible spectrum from 543 nm to 785 nm. • The incorporating of bromide into MAPbI{sub 3−x}Br{sub x} shifts the PL emission to shorter wavelengths. - Abstract: Mixed bromide iodide lead perovskites were prepared from methylamine, lead nitrate and the corresponding hydroX acid (X = I, Br), they were then deposited as thin films on ITO substrate by the spin coating process. X-ray diffraction analyses indicated the formation of a tetragonal phase I4/mcm up to x = 0.4 and a cubic perovskite with space group Pm3 m in the composition range of 0.6 ≤ x ≤ 1. Mixed lead perovskites showed a high absorbance in the UV–vis range. The band gap energy of thin films were estimated from absorbance spectral measurements, it was found that the onset of the absorption edge for MAPbI{sub 3−x}Br{sub x} (x < 1) thin films is ranging between 1.58 to 1.72 eV. Photoluminescence emission energies for mixed halide perovskites presented intermediate values from 781 nm (MAPbI{sub 3}) to 545 nm (MAPbBr{sub 3}).

  7. Exploring the C-X…π Halogen Bonding Motif: An Infrared and Raman Study of the Complexes of CF3X (X = Cl, Br and I with the Aromatic Model Compounds Benzene and Toluene

    Directory of Open Access Journals (Sweden)

    Wouter A. Herrebout

    2013-06-01

    Full Text Available The formation of halogen bonded complexes formed between the trifluorohalomethanes CF3Cl, CF3Br and CF3I and the Lewis bases benzene and toluene at temperatures below 150K was investigated using FTIR and Raman spectroscopy. Experiments using liquid krypton as solvent show that for both CF3Br and CF3I substantial fractions of the monomers can be involved in 1:1 complexes. In addition, weak absorptions illustrating the formation of 2:1 complexes between CF3I and benzene are observed. Using spectra recorded at temperatures between 120 and 140 K, observed information on the relative stability was obtained for all complexes by determining the complexation enthalpies in solution. The resulting values for CF3Br.benzene, CF3I.benzene and (CF3I2.benzene are −6.5(3, −7.6(2 and −14.5(9 kJ mol−1. The values for CF3Br.toluene and CF3I.toluene are −6.2(5 and −7.4(5 kJ mol−1. The experimental complexation enthalpies are compared with theoretical data obtained by combining results from MP2/aug-cc-pVDZ(-PP and MP2/aug-cc-pVTZ(-PP ab initio calculations, from statistical thermodynamical calculations and from Monte Carlo Free Energy Perturbation simulations. The data are also compared with results derived for other C-X···π halogen bonded complexes involving unsaturated Lewis bases such as ethene and ethyne.

  8. Role of the chemical substitution on the structural and luminescence properties of the mixed halide perovskite thin MAPbI_3_−_xBr_x (0 ≤ x ≤ 1) films

    International Nuclear Information System (INIS)

    Atourki, Lahoucine; Vega, Erika; Marí, Bernabé; Mollar, Miguel; Ait Ahsaine, Hassan; Bouabid, Khalid; Ihlal, Ahmed

    2016-01-01

    Highlights: • X-ray diffraction analyses indicate the formation of a tetragonal phase I4/mcm up to x = 0.4 and a cubic perovskite with space group Pm3 m across in the composition range of 0.6 ≤ x ≤ 1. • Perovskite films exhibit a very high absorbance in the visible and short infrared. • As the fraction of bromide change, the adsorption edge of thin film perovskite can be tuned along the visible spectrum from 543 nm to 785 nm. • The incorporating of bromide into MAPbI_3_−_xBr_x shifts the PL emission to shorter wavelengths. - Abstract: Mixed bromide iodide lead perovskites were prepared from methylamine, lead nitrate and the corresponding hydroX acid (X = I, Br), they were then deposited as thin films on ITO substrate by the spin coating process. X-ray diffraction analyses indicated the formation of a tetragonal phase I4/mcm up to x = 0.4 and a cubic perovskite with space group Pm3 m in the composition range of 0.6 ≤ x ≤ 1. Mixed lead perovskites showed a high absorbance in the UV–vis range. The band gap energy of thin films were estimated from absorbance spectral measurements, it was found that the onset of the absorption edge for MAPbI_3_−_xBr_x (x < 1) thin films is ranging between 1.58 to 1.72 eV. Photoluminescence emission energies for mixed halide perovskites presented intermediate values from 781 nm (MAPbI_3) to 545 nm (MAPbBr_3).

  9. Quantum Chemical Examination of the Sequential Halogen Incorporation Scheme for the Modeling of Speciation of I/Br/Cl-Containing Trihalomethanes.

    Science.gov (United States)

    Zhang, Chenyang; Li, Maodong; Han, Xuze; Yan, Mingquan

    2018-02-20

    The recently developed three-step ternary halogenation model interprets the incorporation of chlorine, bromine, and iodine ions into natural organic matter (NOM) and formation of iodine-, bromine-, and chlorine-containing trihalomethanes (THMs) based on the competition of iodine, bromine, and chlorine species at each node of the halogenation sequence. This competition is accounted for using the dimensionless ratios (denoted as γ) of kinetic rates of reactions of the initial attack sites or halogenated intermediates with chlorine, bromine, and iodine ions. However, correlations between the model predictions made and mechanistic aspects of the incorporation of halogen species need to be ascertained in more detail. In this study, quantum chemistry calculations were first used to probe the formation mechanism of 10 species of Cl-/Br-/I- THMs. The HOMO energy (E HOMO ) of each mono-, bi-, or trihalomethanes were calculated by B3LYP method in Gaussian 09 software. Linear correlations were found to exist between the logarithms of experimentally determined kinetic preference coefficients γ reported in prior research and, on the other hand, differences of E HOMO values between brominated/iodinated and chlorinated halomethanes. One notable exception from this trend was that observed for the incorporation of iodine into mono- and di-iodinated intermediates. These observations confirm the three-step halogen incorporation sequence and the factor γ in the statistical model. The combined use of quantum chemistry calculations and the ternary sequential halogenation model provides a new insight into the microscopic nature of NOM-halogen interactions and the trends seen in the behavior of γ factors incorporated in the THM speciation models.

  10. The experience of the fuel waste management of AM and BR-10 reactor facilities at SSC RF IPPE named after A.I. Leipunsky

    International Nuclear Information System (INIS)

    Kochetkov, L.A.; Mamaev, L.I.; Stuzhnev, Yu.A.

    1999-01-01

    8 research and experimental reactors have been created at the Institute industrial site. The majority of them have been or are being decommissioned now. During many decades the reactor of the first-in-the-world NPP -AM and the fast neutron reactor BR-5 (BR-10) are the main research reactor bases of the Institute. They have been in operation for 45 and 40 years respectively. At present the preparation work for their decommissioning is being carried out. One of the problems of that process is the fuel waste management which amount is about 13 tons. The possibility of its reprocessing is under consideration. (author)

  11. Electric Multipole Moments and (HyperPolarizability of X–C≡C–X, X = F, Cl, Br and I

    Directory of Open Access Journals (Sweden)

    Demetrios Xenides

    2003-04-01

    Full Text Available Abstract: We have calculated self-consistent field (SCF and second-order Møller-Plesset perturbation theory (MP2 for the dihaloethynes X–C≡C–X, X = F, Cl, Br and I. All calculations have been performed with carefully optimized, flexible basis sets of gaussiantype functions. Our best values for the quadrupole moment (Θ/ea02 are -0.6524 (FCCF, 3.6612 (ClCCCl, 5.8143 (BrCCBr and 8.3774 (ICCI. The dipole polarizability is strongly anisotropic. For the mean (α /e2a02Eh-1 and the anisotropy (Δα/e2a02Eh-1 we obtain 23.58 and 15.09 (FCCF, 51.75 and 48.30 (ClCCCl, 66.53 and 60.04 (BrCCBr, 93.79 and 78.91 (ICCI. The mean dipole hyperpolarizability (γ /e4a04Eh-3 increases rapidly as 2932 (FCCF, 9924 (ClCCCl, 17409 (BrCCBr and 35193 (ICCI. The transversal component of the hyperpolarizability is larger than the longitudinal one for FCCF, γxxxx > γzzzz but this is reversed for the other molecules in the series. Difluoroethyne is less (hyperpolarizable than ethyne.

  12. Cd4As2Br3

    Directory of Open Access Journals (Sweden)

    Mohammed Kars

    2014-03-01

    Full Text Available Single crystals of Cd4As2Br3 (tetracadmium biarsenide tribromide were grown by a chemical transport reaction. The structure is isotypic with the members of the cadmium and mercury pnictidohalides family with general formula M4A2X3 (M = Cd, Hg; A = P, As, Sb; X = Cl, Br, I and contains two independent As atoms on special positions with site symmetry -3 and two independent Cd atoms, of which one is on a special position with site symmetry -3. The Cd4As2Br3 structure consists of AsCd4 tetrahedra sharing vertices with isolated As2Cd6 octahedra that contain As–As dumbbells in the centre of the octahedron. The Br atoms are located in the voids of this three-dimensional arrangement and bridge the different polyhedra through Cd...Br contacts.

  13. Magic Angle Spinning 207 Pb and low temperature deuterium NMR as a tool for studying local order and dynamics in CH 3 NH 3 PbX 3 (X=Cl, Br, I) hybrid perovskites

    OpenAIRE

    Roiland , Claire; trippé-Allard , gaelle; Jemli , K; Alonso , C; ameline , jean-claude; Gautier , Regis; Le Pollès , Laurent; Deleporte , Emmanuelle; Even , Jacky; Katan , Claudine

    2016-01-01

    National audience; Presenting high solar energy conversion efficiencies (>21%), hybrid perovskites APbX 3 (A is a small organic cation, X=Cl, Br, I) have recently become one of the most promising material in the field of photovoltaic devices. Meanwhile, fundamental understanding of what makes these preovskites so smart for photovoltaics remains limited. More then three decades ago, Wasylishen et al. had already revealed the interest of deuterium NMR to investigate the temperature behaviour an...

  14. Hybrid perovskite resulting from the solid-state reaction between the organic cations and perovskite layers of alpha1-(Br-(CH(2))(2)-NH(3))(2)PbI(4).

    Science.gov (United States)

    Sourisseau, Sebastien; Louvain, Nicolas; Bi, Wenhua; Mercier, Nicolas; Rondeau, David; Buzaré, Jean-Yves; Legein, Christophe

    2007-07-23

    The alpha1-(Br-(CH(2))(2)-NH(3))(2)PbI(4) hybrid perovskite undergoes a solid-state transformation, that is, the reaction between the organic cations and the perovskite layers to give the new hybrid perovskite (Br-(CH(2))(2)-NH(3))(2-x)(I-(CH(2))(2)-NH(3))(x)PbBr(x)I(4-x), based on mixed halide inorganic layers. This transformation has been followed by a conventional powder X-ray diffraction system equipped with a super speed detector, and both solid-state (13)C NMR and ESI/MS measurements have been adopted in the estimation of the rate of halide substitution. The first reaction step leads to the special composition of x approximately 1 (A phase), while the complete substitution is not achieved even at elevated temperature (x(max) approximately 1.85 (B phase)). This unprecedented solid-state reaction between organic and inorganic components of a hybrid perovskite can be considered as a completely new strategy to achieve interesting hybrid perovskites.

  15. Preparation Effects on the Performance of Silica-Doped Hydrous Titanium Oxide (HTO:Si)-Supported Pt Catalysts for Lean-Burn NOx Reduction by Hydrocarbons; TOPICAL

    International Nuclear Information System (INIS)

    GARDNER, TIMOTHY J.; MCLAUGHLIN, LINDA I.; MOWERY, DEBORAH L.; SANDOVAL, RONALD S.

    2002-01-01

    This report describes the development of bulk hydrous titanium oxide (HTO)- and silica-doped hydrous titanium oxide (HTO:Si)-supported Pt catalysts for lean-burn NOx catalyst applications. The effects of various preparation methods, including both anion and cation exchange, and specifically the effect of Na content on the performance of Pt/HTO:Si catalysts, were evaluated. Pt/HTO:Si catalysts with low Na content ( and lt; 0.5 wt.%) were found to be very active for NOx reduction in simulated lean-burn exhaust environments utilizing propylene as the major reductant species. The activity and performance of these low Na Pt/HTO:Si catalysts were comparable to supported Pt catalysts prepared using conventional oxide or zeolite supports. In ramp down temperature profile test conditions, Pt/HTO:Si catalysts with Na contents in the range of 3-5 wt.% showed a wide temperature window of appreciable NOx conversion relative to low Na Pt/HTO:Si catalysts. Full reactant species analysis using both ramp up and isothermal test conditions with the high Na Pt/HTO:Si catalysts, as well as diffuse reflectance FTIR studies, showed that this phenomenon was related to transient NOx storage effects associated with NaNO(sub 2)/NaNO(sub 3) formation. These nitrite/nitrate species were found to decompose and release NOx at temperatures above 300 C in the reaction environment (ramp up profile). A separate NOx uptake experiment at 275 C in NO/N(sub 2)/O(sub 2) showed that the Na phase was inefficiently utilized for NOx storage. Steady state tests showed that the effect of increased Na content was to delay NOx light-off and to decrease the maximum NOx conversion. Similar results were observed for high K Pt/HTO:Si catalysts, and the effects of high alkali content were found to be independent of the sample preparation technique. Catalyst characterization (BET surface area, H(sub 2) chemisorption, and transmission electron microscopy) was performed to elucidate differences between the HTO- and HTO

  16. Tritium ( 3 H) Retention In Mice: Administered As HTO, DTO or as 3 H-Labeled Amino-Acids.

    Science.gov (United States)

    Priest, Nicholas D; Blimkie, Melinda S J; Wyatt, Heather; Bugden, Michelle; Bannister, Laura A; Gueguen, Yann; Jourdain, Jean-Rene; Klokov, Dmitry

    2017-05-01

    The objective of this study was to compare the biokinetics of injected H-labeled light (HTO) and heavy (DTO) water in CBA/CaJ mice and to compare the organ distribution and/or body content of H administered by chronic ingestion for 1 mo to C57Bl/6J mice, as either H-labeled water or H-labeled amino acids (glycine, alanine and proline). HTO and DTO were administered to CBA/CaJ mice by single intraperitoneal injection and body retention was determined for up to 384 h post-injection. Tritium-labeled water or H-labeled amino acids were given to C57Bl/6J mice ad libitum for 30 d in drinking water. Body content and organ distribution of H during the period of administration and subsequent to administration was determined by liquid scintillation counting. No differences were found between the biokinetics of HTO and DTO, indicating that data generated using HTO can be used to help assess the consequences of H releases from heavy water reactors. The results for H-water showed that the concentration of radionuclide in the mice reached a peak after about 10 d and dropped rapidly after the cessation of H administration. The maximum concentration reached was only 50% of that in the water consumed, indicating that mice receive a significant fraction of their water from respiration. Contrary to the findings of others, the pattern of H retention following the administration of a cocktail of the labeled amino acids was very little different from that found for the water. This is consistent with the suggestion that most of the ingested amino acids were rapidly metabolized, releasing water and carbon dioxide.

  17. Technical realization of the VISA-2 Project, contract: 2.01/ I phase, Volume No. I; Tehnicka realizacija projekta VISA-2, ugovor: 2.01/I faza, Album br. I

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1963-12-15

    Cooperation between the Institutes in Vinca and Saclay has started by carrying out the task 'Technical realization of the VISA-2 project' which should enable: obtaining new experimental spaces in the RA reactor with high fast neutron flux for sample irradiation; obtaining experience in reactor continual operation for few months at nominal power of 6.5 MW and increase of RA reactor utilization; solving the problem of activated channels and samples transport, problems of working in hot cells; obtaining irradiated samples for examining radiation effects first in Saclay and later in Vinca. The project is divided in three phases. Phase one covers the reconstruction of the RA reactor fuel channels according to the VISA-2 project demands. The second phase includes the activities related to measuring devices for measuring the temperatures at the incoming and outgoing heavy water in 5 VISA-2 channels, as well as temperature of the samples (55 thermocouples) and testing the channels and capsules after their insertion in the reactor. The third phase includes activities are related to problems of transport of radioactive channels and VISA-2 capsules, problems of cutting as well as packing and transporting of irradiated samples from Vinca to Saclay. This volume includes all the relevant documents for completing the task including contracts, needed preliminary calculations as well as safety analysis. [Serbo-Croat] Saradnja izmedju Instituta u Vinci i Saclay-u zapoceta je realizacijom zadatka 'Tehnicka realizacije projekta VISA-2' koji treba da omoguci: dobijanje novih eksperimentalnih prostora u reaktoru RA sa visokom vrednoscu fluksa brzih neutrona za ozracivanje uzoraka; sticanje pogonskih iskustava u visemesecnom kontilualnom radu na nominalnoj snazi od 6,5 MW i povecanje stepena koriscenja reaktora RA; resenje pitanja transporta aktivnih kanala i uzoraka, problema rada u vrucim celijama; dobijanje ozracenih uzoraka za izucavanje, u prvo vreme u Saclay-u, a kasnije i u Vinci

  18. Deviation from the <i>trans> -Effect in Ligand-Exchange Reactions of Zeise’s Ions PtCl3(C2H4)- with Heavier Halides (Br, I- )

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Gao-Lei [Physical; Govind, Niranjan [Environmental; Xantheas, Sotiris S. [Advanced; Department; Wang, Xue-Bin [Physical

    2018-01-16

    Four new Zeise’s family ions with mixed-halide ligands, i.e., PtClnX3-n(C2H4)- (X = Br, I; n = 1, 2), were synthesized via ligand-exchange reactions of KX salts with KPtCl3(C2H4) in aqueous solutions, and were detected in vacuum via electrospray ionization mass spectrometry. Their photoelectron spectra reveal a series of well-resolved spectral peaks with their electron binding energies (EBEs) decreasing with increasing halide size, with I having a much stronger effect than Br, i.e., 4.57 (–Cl3) > 4.56 (–Cl2Br) > 4.53 (–ClBr2) > 4.34 (–Cl2I) > 4.30 eV (–ClI2). Ab initio electronic structure calculations including spin-orbit coupling (SOC) predict that the cis- and trans-isomers are nearly isoenergetic with the cis-isomer for –Cl2X, and the trans-isomer for –ClX2 slightly favored, respectively. Excited-state spectra calculated with time-dependent density functional theory (TDDFT), and their comparison with the observed ones, suggest that for each species, both the cis- and trans-configurations coexist in the experiments and contribute to the observed spectra, a fact that clearly violates the prediction of the widely accepted trans-effect, which suggests that only one isomer would have formed.

  19. Validation of the HTO-18 method for determination of CO2 production of lizards (genus Sceloporus)

    International Nuclear Information System (INIS)

    Congdon, J.D.; King, W.W.; Nagy, K.A.

    1978-01-01

    The accuracy of doubly-labeled water measurements of CO 2 production in lizards of the genus Sceloporus was assessed by comparison of CO 2 production rates determined simultaneously by labeled water and gas chromatography. Five lizards were weighed and given intraperitoneal injections of 55 μl of water containing 10 microcuries of tritium as HTO and 50 atom % oxygen-18 as H 2 18 O. Initial blood samples were taken from the infraorbital sinus ten hours later, and the lizards were placed in sealed metabolism chambers kept at 28 C. After 179 h the lizards were weighed and blood samples taken. Blood samples were microdistilled, assayed for tritium activity and for oxygen-18 content. Isotope measurements were used to calculate rates of CO 2 production. Gas samples were withdrawn from each chamber after 18, 63, 109, and 179 h and measured against 0.5 and 1.0% CO 2 standards with a Beckman GC-55 gas chromatograph fitted with silica gel 42-60 mesh column. These results were used to calculate rates of CO 2 production. Results supported the conclusion that the doubly-labeled water method accurately measured rates of CO 2 production in Sceloporus lizards, and could therefore be a valuable technique in field studies of lizard energetics

  20. The BR eigenvalue algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Geist, G.A. [Oak Ridge National Lab., TN (United States). Computer Science and Mathematics Div.; Howell, G.W. [Florida Inst. of Tech., Melbourne, FL (United States). Dept. of Applied Mathematics; Watkins, D.S. [Washington State Univ., Pullman, WA (United States). Dept. of Pure and Applied Mathematics

    1997-11-01

    The BR algorithm, a new method for calculating the eigenvalues of an upper Hessenberg matrix, is introduced. It is a bulge-chasing algorithm like the QR algorithm, but, unlike the QR algorithm, it is well adapted to computing the eigenvalues of the narrowband, nearly tridiagonal matrices generated by the look-ahead Lanczos process. This paper describes the BR algorithm and gives numerical evidence that it works well in conjunction with the Lanczos process. On the biggest problems run so far, the BR algorithm beats the QR algorithm by a factor of 30--60 in computing time and a factor of over 100 in matrix storage space.

  1. DFT investigation of electronic structures and magnetic properties of halides family MeHal3 (Me=Ti, Mo,Zr,Nb, Ru, Hal=Cl,Br,I) one dimensional structures

    Science.gov (United States)

    Kuzubov, A. A.; Kovaleva, E. A.; Popova, M. I.; Kholtobina, A. S.; Mikhaleva, N. S.; Visotin, M. A.; Fedorov, A. S.

    2017-10-01

    Using DFT GGA calculations, electronic structure and magnetic properties of wide family of transition metal trihalides (TMHal3) (Zr, Ti and Nb iodides, Mo, Ru, Ti and Zr bromides and Ti or Zr chlorides) are investigated. These structures consist of transition metal atoms chains surrounded by halides atoms. Chains are connected to each other by weak interactions. All TMHal3 compounds were found to be conductive along chain axis except of MoBr3 which is indirect gap semiconductor. It was shown that NbI3 and MoBr3 have large magnetic moments on metal atoms (1.17 and 1.81 μB, respectively) but other TMHal3 materials have small or zero magnetic moments. For all structures ferromagnetic and anti-ferromagnetic phases have almost the same energies. The causes of these properties are debated.

  2. Brændeovnes bidrag til luftforurening

    DEFF Research Database (Denmark)

    Pedersen, Jens Christian

    2010-01-01

    Brændeovnenes bidrag til luftforurening er blevet kortlagt med en hidtil uset detaljeringsgrad. Det er forskere fra Danmarks Miljøundersøgelser (DMU) på Aarhus Universitet som står bag kortlægningen. En omfattende målekampagne i Slagslunde viser at brændeovnene bidrager væsentligt til partikelfor......Brændeovnenes bidrag til luftforurening er blevet kortlagt med en hidtil uset detaljeringsgrad. Det er forskere fra Danmarks Miljøundersøgelser (DMU) på Aarhus Universitet som står bag kortlægningen. En omfattende målekampagne i Slagslunde viser at brændeovnene bidrager væsentligt til...

  3. Qualitative analysis of Th-232 in soil samples with portable radiological identifiers NaI (Tl) and LaBr{sub 3} (Ce); Análise qualitativa de Th-232 em amostras de solo com identificadores radiológicos portáteis NaI(Tl) e LaBr{sub 3}(Ce)

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, L.S.R.; Amorim, A.S.; Balthar, M.C.V.; Vilela, P.RT.; Santos, A. [Instituto de Defesa, Química, Biológica, Radiológica e Nuclear (IDQBRN), Rio de Janeiro, RJ (Brazil); Cardoso, D.O.; Izidoro, A.C.A.C. [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Pelegrineli, S.Q.; Silva, L.B.; Silva, S.L. [MAXIM Treinamento e Assessoria, Rio de Janeiro, RJ (Brazil); Santos, F.R.; Ribeiro, C.A.M.; Silva, D.C., E-mail: lucianosantarita@gmail.com, E-mail: domingosoliveiralvr71@gmail.com, E-mail: samuelfisica@yahoo.com.br [Universidade Estácio de Sá, Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The identification of the occurrence of Th-232 in open environments using portable radiological identifiers (IRP) with scintillators, discriminating the environmental condition and NORM is important for the operational teams of the Institute of Chemical, Biological, Radiological and Nuclear Defense (IDQBRN) of the Army. The qualitative analysis by gamma energy spectrometry for the energies of Th-232 and its daughter radioisotopes, given the resolution that characterizes the scintillation crystals (NaI (Tl) - 7.5% and LaBr{sub 3} (Ce) - 2.9%) makes it possible to identify them. The purpose is to perform a qualitative analysis of the reliability of the response of these IRPs to the measurements of Th-232 generally found in the environment and in samples extracted from points where the thorium concentration is highest. The results show that the identification of this radionuclide by the IRP in the samples with the highest natural occurrence is achieved by measuring the energies of the daughter isotopes Ac-228, Tl-208, Bi-212 and Pb-212 allowing the discrimination of soils with natural occurrence of Th -232 and NORM. These measurements will be based on the procedures used by the operational teams in the field actions aimed at reducing exposure to this radiation, both for individuals occupationally exposed and for the population.

  4. UV-VIS absorption spectra of molten AgCl and AgBr and of their mixtures with group I and II halide salts

    Energy Technology Data Exchange (ETDEWEB)

    Greening, Giorgio G.W. [Technische Universitaet Darmstadt (Germany). Eduard-Zintl-Institut fuer Anorganische und Physikalische Chemie

    2015-07-01

    The UV-VIS absorption spectra of (Ag{sub 1-X}[Li-Cs, Ba]{sub X})Cl and of (Ag{sub 1-X}[Na, K, Cs]{sub X})Br at 823 K at the concentrations X=0.0, 0.1, 0.2 have been measured. The findings show that on adding the respective halides to molten silver chloride and silver bromide, shifts of the fundamental absorption edge to shorter wavelengths result. A correlation between the observed shifts and the expansion of the silver sub-lattice is found, which is valid for both silver halide systems studied in this work.

  5. Behavior of Halogen Bonds of the Y-X⋅⋅⋅π Type (X, Y=F, Cl, Br, I) in the Benzene π System, Elucidated by Using a Quantum Theory of Atoms in Molecules Dual-Functional Analysis.

    Science.gov (United States)

    Sugibayashi, Yuji; Hayashi, Satoko; Nakanishi, Waro

    2016-08-18

    The nature of halogen bonds of the Y-X-✶-π(C6 H6 ) type (X, Y=F, Cl, Br, and I) have been elucidated by using the quantum theory of atoms in molecules (QTAIM) dual-functional analysis (QTAIM-DFA), which we proposed recently. Asterisks (✶) emphasize the presence of bond-critical points (BCPs) in the interactions in question. Total electron energy densities, Hb (rc ), are plotted versus Hb (rc )-Vb (rc )/2 [=(ħ(2) /8m)∇(2) ρb (rc )] for the interactions in QTAIM-DFA, in which Vb (rc ) are potential energy densities at the BCPs. Data for perturbed structures around fully optimized structures were used for the plots, in addition to those of the fully optimized ones. The plots were analyzed by using the polar (R, θ) coordinate for the data of fully optimized structures with (θp , κp ) for those that contained the perturbed structures; θp corresponds to the tangent line of the plot and κp is the curvature. Whereas (R, θ) corresponds to the static nature, (θp , κp ) represents the dynamic nature of the interactions. All interactions in Y-X-✶-π(C6 H6 ) are classified by pure closed-shell interactions and characterized to have vdW nature, except for Y-I-✶-π(C6 H6 ) (Y=F, Cl, Br) and F-Br-✶-π(C6 H6 ), which have typical hydrogen-bond nature without covalency. I-I-✶-π(C6 H6 ) has a borderline nature between the two. Y-F-✶-π(C6 H6 ) (Y=Br, I) were optimized as bent forms, in which Y-✶-π interactions were detected. The Y-✶-π interactions in the bent forms are predicted to be substantially weaker than those in the linear F-Y-✶-π(C6 H6 ) forms. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Investigation of tritium transfer to plants via the OBT/HTO and OBT/TFWT ratios; Etude du transfert du tritium aux vegetaux via les ratios OBT/HTO ET OBT/TFWT

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, C.; Guetat, P.; Vichot, L.; Losset, Y. [CEA Valduc, UMR, 21 - Is-sur-Tille (France); Boyer, C.; Fromm, M.; Mavon, C. [UMR CEA E4, Universite de Franche-Comte, 16 route de Gray, F-25030 Besancon cedex (France); Boyer, C.; Tatin-Froux, F.; Badot, P.M. [CNRS-Universite de Franche Comte / UMR 6249 Chrono-environnement usc INRA, Place Leclerc, F-25030 Besancon cedex (France)

    2009-07-01

    After having recalled some concepts used to distinguish the various forms of water present in plants, and the reactions in presence of tritium, the authors discuss the biochemical behaviour of tritium. Then, they briefly report a literature survey and, for different plants and crops, indicate the values of the OBT/HTO (organically bound tritium/tritiated water) and OBT/TFWT (organically bound tritium/tissue free water tritium) ratios. They also report experimental studies performed by exposures of lettuces at the vicinity of a nuclear installation

  7. Excitation functions and yields of proton induced reactions at intermediate energies leading to important diagnostics radioisotopes of 52Fe, 77Br, 82Rb, 97Ru, 111In, 123I, 127Xe, 128Cs, 178Ta and 201Tl

    International Nuclear Information System (INIS)

    Rurarz, E.

    1994-01-01

    This report describes investigations of the excitation functions of the proton induced reactions on 14 targets (Mn, Co, Br, Rb, 99 Tc, 113 Cd, 114 Cd, Cd, I, Cs, Ta, 206,207,208 Pb) leading directly or indirectly to the formation of radionuclides 52 Fe, 77 Br, 82 Rb, 97 Ru, 111 In, 123 I, 127 Xe, 128 Cs, 178 Ta and 201 Tl frequently used in diagnostic procedures of nuclear medicine. The measurements of the excitation functions were made over a wide proton energy range from the reaction threshold up to 100 MeV using the stacked foil (or pellet) technique. Small energy steps were used to allow for accurate determination of the structure of excitation functions. For 97 Ru, 111 In and 127 Xe formation with protons, new reaction channels and targets were used and data concerning this method are published for the first time. The data for 52 Fe, 77 Br, 82 Rb, 123 I, 128 Cs and 201 Tl obtained in the present work for the E p =70-100 MeV region are also published for the first time. The measured excitation functions for the formation of desired (and undesired) radionuclides (altogether 28 excitation functions) are compared with the theoretical ones calculated on the basis of a hybrid model of nuclear reactions in the form of the Overlaid Alice computer code. In order to determine the contribution of the competitive reaction channels to the purity of the produced, desired radionuclide, the excitation functions of the accompanying reactions were also calculated. The 122 calculated excitation functions for the possible contaminant are given in the present work. The comparison of experimental excitation functions with the results of model calculations showed satisfactory agreement, especially if one considers, that no parameter adjustment for individual reaction products was undertaken. From the measured excitation functions the production yields for 28 radionuclides mentioned above have been determined (author). 262 refs, 65 figs, 34 tabs

  8. Determining the amount of Br, Na and K in six wheat samples with neutron activation analysis (NAA) method in Arak, I.R. Iran

    International Nuclear Information System (INIS)

    Reza Pourimani; Khatoon Abasnejad; Khadijeh Ghanbarzadeh; Mohammad Reza Zare; Mahdi Kamali

    2013-01-01

    Accurate knowledge of the trace elemental concentrations in wheat and its products is of great importance from a nutritional point of view. In this study, six wheat samples were prepared from the agriculture research center of Arak named Sardari, Amir, MV-17, Batava, Karaj-2 and Alvand; they were analyzed by neutron activation method (NAA). In this method, Isfahan miniature reactor as a neutron source and relative NAA method has been used as the analysis type. In this design in order to record gamma spectrum the MCA system and high purity germanium detector were used. Finally, the concentration of the trace elements such as Br, K and Na value was determined for the Sardari, Amir, Alvand, MV-17, Batava, Karaj-2 wheat samples. The average concentration of trace elements in all wheat samples in the studied area are 2.41(0.8597-6.1175) mg kg -1 for Br, 13.42(8.7063-24.696) mg kg -1 for Na and 463.30(434.22-505.45) mg kg -1 for K, respectively. These were compared with other reports results. This study has been conducted as the first time for this region. (author)

  9. Production of 68Ge, 64Cu, 86Y, 89Zr, 73Se, 77Br and 124I positron emitting radionuclides through future laser-accelerated proton beams at ELI-Beamlines for innovative PET diagnostics

    OpenAIRE

    Italiano, Antonio; Amato, Ernesto; Minutoli, Fabio; Margarone, Daniele; Baldari, Sergio

    2016-01-01

    The development of innovative production pathways for high-Z positron emitters is of great interest to enlarge the applicability of PET diagnostics, especially in view of the continuous development of new radiopharmaceuticals. We evaluated the theoretical yields of 64Cu, 86Y, 89Zr, 73Se, 77Br and 124I PET isotopes, plus the 68Ge isotope, parent of the 68Ga positron emitter, in the hypothesis of production through laser-accelerated proton sources expected at the ELI-Beamlines facility. By mean...

  10. Reactor BR2: Introduction

    International Nuclear Information System (INIS)

    Gubel, P.

    2000-01-01

    The BR2 reactor is still SCK-CEN's most important nuclear facility. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. A safety audit was conduced by the IAEA, the conclusions of which demonstrated the excellent performance of the plant in terms of operational safety. In 1999, the CALLISTO facility was extensively used for various programmes involving LWR pressure vessel materials, IASCC of LWR structural materials, fusion reactor materials and martensic steels for use in ADS systems. In 1999, BR2's commercial programmes were further developed

  11. Diffusion of Tritiated Water (HTO) and 22Na+-Ions through Non-Degraded Hardened Cement Pastes - II. Modelling Results

    International Nuclear Information System (INIS)

    Jakob, A.

    2002-12-01

    In this report, the procedure and the results of an inverse modelling study on the through-diffusion of tritiated water (HTO) and 2 2Na + -ions are presented using high-porous hardened cement pastes with a water/cement ratio of 1.3 in the first stage of the cement degradation. For the analysis two alternative models were applied: 1) a diffusion model where a possible sorption of the tracer was entirely neglected, and 2) a diffusion model with linear sorption. The analysis of the through-diffusion phase allowed extracting values for the effective diffusion coefficient (D e ) and the rock-capacity factor (α). Both models could fit the breakthrough curves equally well, and also mass-balance considerations did not allow to clearly preferring one of the two competing models to the other. But blind-predictions for tracer out-diffusion using the best-fit parameter values deduced from analysing the former through-diffusion phase gave a clear indication that linear sorption had to be included in the diffusion model. The extracted K d values for HTO are in excellent agreement with values from batch sorption experiments and are of the order of 0.8. 10 -3 m 3 /kg. Those for 2 2Na + are of the order of 1.0. 10 -3 m 3 /kg and are by a factor of two larger than values from batch sorption experiments. The values for the effective diffusion coefficients for HTO are of the order of (2-3).10 -1 0 m 2 /s, and those for sodium are roughly by a factor of two smaller than values for HTO. On the one hand, the observed tracer uptake could only partially be addressed to isotope exchange; the most obvious process which could account for the remaining part of the uptaken tracer mass is diffusion into a second type of porosity, the dead-end pores. On the other hand, the results and conclusions drawn are encouraging for future investigations; therefore no major deficiency concerning the applied equipment and the modelling methodology could be detected. In the report, however, some suggestions

  12. Electronic structure of f1 actinide complexes. Pt. 3. Quasi-relativistic density functional calculations of the optical transition energies of PaX62-(X=F,Cl,Br,I)

    International Nuclear Information System (INIS)

    Kaltsoyannis, N.

    1998-01-01

    For pt.II see J. Organomet. Chem., vol.528, p.19, 1997. The four f→f transition energies of the single 5f-based electron of PaX 6 2- (X=F, Cl, Br, I) have been calculated using quasi-relativistic local density functional theory. Excellent agreement ( -1 ) between theory and experiment is obtained for PaCl 6 2- , PaBr 6 2- and PaI 6 2- by variation of the value of α in the Xα exchange-only functional. In contrast, more sophisticated calculational methods including non-local corrections fail to reproduce the experiments well. The PaF 6 2- results are less impressive (up to 1000 cm -1 discrepancy), possibly due to non-aufbau orbital occupations for certain values of α. The values of α employed lie in the range 0.79-0.85, somewhat higher than the most widely used value of 0.7. The theoretical basis for using such values is discussed. (orig.)

  13. Electronic structure calculations and optical properties of a new organic-inorganic luminescent perovskite: (C{sub 9}H{sub 19}NH{sub 3}){sub 2}PbI{sub 2}Br{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Abid, H., E-mail: haithamlpa@yahoo.fr [Laboratoire de Physique Appliquee, Faculte des sciences, Universite de Sfax (Tunisia); Institut Neel, CNRS-Universite J. Fourier, BP 166, 38042 Grenoble (France); Samet, A.; Dammak, T. [Laboratoire de Physique Appliquee, Faculte des sciences, Universite de Sfax (Tunisia); Mlayah, A. [Centre d' Elaboration de Materiaux et d' Etudes Structurales (CEMES), CNRS-Universite de Toulouse, 29 rue Jeanne Marvig, 31055 Toulouse (France); Hlil, E.K. [Institut Neel, CNRS-Universite J. Fourier, BP 166, 38042 Grenoble (France); Abid, Y. [Laboratoire de Physique Appliquee, Faculte des sciences, Universite de Sfax (Tunisia)

    2011-08-15

    (C{sub 9}H{sub 19}NH{sub 3}){sub 2}PbI{sub 2}Br{sub 2} compound is a new crystal belonging to the large hybrid organic-inorganic perovskites compounds family. Optical properties are investigated by optical absorption UV-visible and photoluminescence (PL) techniques. Bands to band absorption peak at 2.44 eV as well as an extremely strong yellow-green photoluminescence emission at 2.17 eV is observed at room temperature. First principle calculations based on the DFT and FLAPW methods combined with LDA approximation are performed as well. Density of state close to the gap is presented and discussed in terms of optical absorption and photoluminescence experimental results. The perfect agreement between experimental data and electronic structure calculations is highlighted. - Highlights: > (C{sub 9}H{sub 19}NH{sub 3}){sub 2}PbI{sub 2}Br{sub 2} compound is a new crystal with strong yellow-green PL emission at 2.17 eV. > Calculations based on DFT and FLAPW method combined with LDA approximation are performed. > Gap, optical transitions and exciton presence were predicted from density of states. > Agreement between experimental data and electronic structure calculations.

  14. Crystal structures of palladium(II) ternary complexes of 5-x-2-aminobenzoic acid with 1,10-phenanthroline and their interaction with calf thymus DNA (where X=Cl, Br and I).

    Science.gov (United States)

    Wang, Yue; Okabe, Nobuo; Odoko, Mamiko

    2005-10-01

    The crystal structures of a series of three palladium(II) ternary complexes of 5-halogeno-2-aminobenzoic acid (5-X-AB, where X=Cl, Br and I) with 1,10-phenanthroline [Pd(5-Cl-AB)(phen)] (1), [Pd(5-Br-AB)(phen)] (2) and [Pd(5-I-AB)(phen)] (3) have been determined, and their coordination geometries and the crystal architecture characterized. All of the complexes are an isostructure in which each Pd(II) atom has basically similar square planar coordination geometry. The substitute halogen group at 5-position of AB plays an important role in producing the coordination bonds of the carboxylate and amino groups in which the carboxylate O atom and the amino N atom act as the negative monodentate ligand atoms. The coordination bond distances of O-Pd increase in the order 1<2<3, while those of N-Pd decrease in the same order. The binding of the complexes to the calf thymus DNA has also been studied by the fluorescence method. Each of the complexes shows high binding propensity to DNA which can be reflected as the relative order 1<2<3.

  15. Hybridization of Single Nanocrystals of Cs4PbBr6 and CsPbBr3.

    Science.gov (United States)

    Weerd, Chris de; Lin, Junhao; Gomez, Leyre; Fujiwara, Yasufumi; Suenaga, Kazutomo; Gregorkiewicz, Tom

    2017-09-07

    Nanocrystals of all-inorganic cesium lead halide perovskites (CsPbX 3 , X = Cl, Br, I) feature high absorption and efficient narrow-band emission which renders them promising for future generation of photovoltaic and optoelectronic devices. Colloidal ensembles of these nanocrystals can be conveniently prepared by chemical synthesis. However, in the case of CsPbBr 3 , its synthesis can also yield nanocrystals of Cs 4 PbBr 6 and the properties of the two are easily confused. Here, we investigate in detail the optical characteristics of simultaneously synthesized green-emitting CsPbBr 3 and insulating Cs 4 PbBr 6 nanocrystals. We demonstrate that, in this case, the two materials inevitably hybridize, forming nanoparticles with a spherical shape. The actual amount of these Cs 4 PbBr 6 nanocrystals and nanohybrids increases for synthesis at lower temperatures, i.e., the condition typically used for the development of perovskite CsPbBr 3 nanocrystals with smaller sizes. We use state-of-the-art electron energy loss spectroscopy to characterize nanoparticles at the single object level. This method allows distinguishing between optical characteristics of a pure Cs 4 PbBr 6 and CsPbBr 3 nanocrystal and their nanohybrid. In this way, we resolve some of the recent misconceptions concerning possible visible absorption and emission of Cs 4 PbBr 6 . Our method provides detailed structural characterization, and combined with modeling, we conclusively identify the nanospheres as CsPbBr 3 /Cs 4 PbBr 6 hybrids. We show that the two phases are independent of each other's presence and merge symbiotically. Herein, the optical characteristics of the parent materials are preserved, allowing for an increased absorption in the UV due to Cs 4 PbBr 6 , accompanied by the distinctive efficient green emission resulting from CsPbBr 3 .

  16. XeBr exciplex laser

    International Nuclear Information System (INIS)

    Searles, S.K.

    1976-01-01

    Laser emission from the recently discovered XeBr exciplex laser was investigated as a function of the partial pressures of Xe and Br 2 . An optical loss process appears to limit high-pressure operation

  17. Reactor BR2. Introduction

    International Nuclear Information System (INIS)

    Gubel, P.

    2002-01-01

    The BR2 materials testing reactor is one of SCK-CEN's most important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. In 2001, the reactor was operated for a total of 123 days at a mean power of 59 MW in order to satisfy the irradiation conditions of the internal and external programmes using mainly the CALLISTO PWR loop. The mean consumption of fresh fuel elements was 5.26 per 1000 MWd. Main achievements in 2001 included the development of a three-dimensional full-scale model of the BR2 reactor for simulation and prediction of irradiation conditions for various experiments; the construction of the FUTURE-MT device designed for the irradiation of fuel plates under representative conditions of geometry, neutron spectrum, heat flux and thermal-hydraulic conditions and the development of in-pile instrumentation and a data acquisition system

  18. Reactor BR2. Introduction

    International Nuclear Information System (INIS)

    Gubel, P.

    2001-01-01

    The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given

  19. Reactor BR2. Introduction

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2002-04-01

    The BR2 materials testing reactor is one of SCK-CEN's most important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. In 2001, the reactor was operated for a total of 123 days at a mean power of 59 MW in order to satisfy the irradiation conditions of the internal and external programmes using mainly the CALLISTO PWR loop. The mean consumption of fresh fuel elements was 5.26 per 1000 MWd. Main achievements in 2001 included the development of a three-dimensional full-scale model of the BR2 reactor for simulation and prediction of irradiation conditions for various experiments; the construction of the FUTURE-MT device designed for the irradiation of fuel plates under representative conditions of geometry, neutron spectrum, heat flux and thermal-hydraulic conditions and the development of in-pile instrumentation and a data acquisition system.

  20. Reactor BR2. Introduction

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2001-04-01

    The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given.

  1. Receptionsanalyse og Brødre

    DEFF Research Database (Denmark)

    Hansen, Lennard Højbjerg

    2016-01-01

    Receptionsanalysen omfatter både teori og empiriske undersøgelse. Det er dog først, når man foretager kvalitative undersøgelser af tilskuernes reception, man ser de interessante forskelle i oplevelserne af film. Susanne Biers film "Brødre" danner udgangspunkt for kvalitative interviews med 6...

  2. Angular correlation for gamma-gamma transitions in 81Br and 83Br nuclei

    International Nuclear Information System (INIS)

    Matheus, R.

    1984-01-01

    The directional angular correlation of coincident gamma transitions in 81 Br and 83 Br have been measured following the β - decay of 81 Se(T sub(1/2) = 18.6 min) and 83 Se(T sub(1/2) = 22.6 min) respectively, using Ge(Li) - high purity Ge and Ge(Li)-NaI(Tl) spectrometers. The radioactive sources were prepared by irradiating with neutrons in the IEA-R1 reactor, metallic selenium (natural) to produce 81 Se and samples of metallic selenium enriched (to approx. 90% in 82 Se) to produce 83 Se. Measurements have been carried out for the gamma cascades 260-276 KeV, 290-276 KeV and 552-276 KeV in 81 Br and the gamma cascades 225(510)-356 KeV, 510-356 KeV, 572-(510)-356 KeV, 718-(225)-(510)-356 KeV, 1064-356 KeV, 718-225 KeV, 718-(225)-510 KeV, 836-718 KeV, 718-(225)-866 KeV, 883-718 KeV and 1895-799 KeV in 83 Br. The multipole mixing ratios, σ(E2/M1), were determined for 3 gamma transitions in 81 Br and 11 gamma transitions in 83 Br. In the case of 81 Br present results confirmed some of the earlier results. The spin and parity assignment were made to the majority of levels in 81 Br and 83 Br involved in the present study, some of them confirming the earlier results. A comparison of some of the nuclear properties of the 79 Br, 81 Br and 83 Br is made based on the available experimental data. The experimental results are also discussed qualitatively in terms of some nuclear models applicable for the description of the properties of odd-A bromine isotopes. (Author) [pt

  3. Production of 68Ge, 64Cu, 86Y, 89Zr, 73Se, 77Br and 124I positron emitting radionuclides through future laser-accelerated proton beams at ELI-Beamlines for innovative PET diagnostics

    Directory of Open Access Journals (Sweden)

    Antonio Italiano

    2016-05-01

    Full Text Available The development of innovative production pathways for high-Z positron emitters is of great interest to enlarge the applicability of PET diagnostics, especially in view of the continuous development of new radiopharmaceuticals. We evaluated the theoretical yields of 64Cu, 86Y, 89Zr, 73Se, 77Br and 124I PET isotopes, plus the 68Ge isotope, parent of the 68Ga positron emitter, in the hypothesis of production through laser-accelerated proton sources expected at the ELI-Beamlines facility. By means of the TALYS software we simulated the nuclear reactions leading to the above radionuclides, hypothesizing three possible scenarios of broad proton spectra, with maximum energies of about 9, 40 and 100 MeV. The production yields of the studied radionuclides, within the expected fluences, appear to be suitable for pre-clinical applications.

  4. Synthesis of iridacarborane halide complexes [(η-9-SMe2-7,8-C2B9H10)IrX2]2 (X=Cl, Br, I)

    International Nuclear Information System (INIS)

    Kudinov, A.R.; Perekalin, D.S.; Petrovskij, P.V.

    2001-01-01

    By interaction between Na[9-SMe 2 -7,8-C 2 B 9 H 10 ] and [(Cod)IrCl] 2 (Cod - cycloocta-1,5-diene) iridium complex (η-9-SMe 2 -7,8-C 2 B 9 H 10 )Ir(Cod), which under the action of anhydrous hydrohalogenic acids HX (X=Cl, Br, I) yields iridacarborane halide complexes [(η-9-SMe 2 -7,8-C 2 B 9 H 10 )IrX 2 ] 2 , being analogs of cyclopentadienyl complexes [(C 5 Me 5 )IrX 2 ] 2 . The complexes prepared were characterized on the basis of data of elementary analysis and 1 H, 11 B NMR spectra [ru

  5. Structural and thermodynamic characteristics of X2MYH2 compounds (M Al, Ga, In; X = F, Cl, Br, I; Y = N, P, As) - the products of hydrohalogen elimination from X3MYH3 donor-acceptor complexes

    International Nuclear Information System (INIS)

    Timoshkin, A.Yu.; Suvorov, A.V.; Shefer, G.F.

    2001-01-01

    Geometrical and thermodynamic characteristics of complexes X 2 MYH 2 (M Al, Ga, In; X = F, Cl, Br, I; Y = N, P, As) were obtained by the method of density functional B3LYP. It is shown that nitrogen complexes X 2 MNH 2 have a plane structure, whereas phosphorus and arsenic complexes are pyramidal. In the process of HX elimination the dissociation energy of M-Y bond is strengthened essentially (by 150-270 kJ/mol), which makes dissociation of X 2 MYH 2 into components quite inefficient from thermodynamic viewpoint even at temperatures of about 1000 deg C. Dimerization enthalpies of X 2 MYH 2 lie in the range 40 (Y = P, As) - 260 (Y=N) kJ/mol. Thus, dimers [X 2 MNH 2 ] 2 can be intermediate products in the processes of nitrides chemical precipitation from gaseous phase of donor-acceptor complexes [ru

  6. Photochemistry of xenon-halogen Van der Waals complexes (X2 = Cl2, Br2, I2): evidence for the intermediate states in the (Xe-X2)*→ XeX* + X reaction

    International Nuclear Information System (INIS)

    Boivineau, Michel

    1987-01-01

    This research thesis addresses the reactivity of excited states of xenon-halogen Van der Waals complexes (Cl 2 , Br 2 , I 2 ) submitted to a multi-photonic excitation. The objective of this study is, by means of a specific experimental approach, to highlight the R*+ X 2 *- to better understand the reaction mechanism, and to study the reactivity of rare gas/halogen systems depending on the halogen nature. After having reported a bibliographical study on each studied system, the author describes the experimental system, reports and discusses experimental results obtained on the different complex systems (chlorine-, bromine- or iodine-based). He finally comments a possible and original application of these works in the development of an excimer laser with a new active medium (the rare gas/halogen Van der Waals complex) which would allow a continuous operation and an easy discharge production [fr

  7. Lasagna-type arrays with halide-nitromethane cluster filling. The first recognition of the Hal(-)···HCH2NO2 (Hal = Cl, Br, I) hydrogen bonding.

    Science.gov (United States)

    Gushchin, Pavel V; Kuznetsov, Maxim L; Wang, Qian; Karasik, Andrey A; Haukka, Matti; Starova, Galina L; Kukushkin, Vadim Yu

    2012-06-21

    The previously predicted ability of the methyl group of nitromethane to form hydrogen bonding with halides is now confirmed experimentally based on X-ray data of novel nitromethane solvates followed by theoretical ab initio calculations at the MP2 level of theory. The cationic (1,3,5-triazapentadiene)Pt(II) complexes [Pt{HN=C(NC(5)H(10))N(Ph)C(NH(2))=NPh}(2)](Cl)(2), [1](Hal)(2) (Hal = Cl, Br, I), and [Pt{HN=C(NC(4)H(8)O)N(Ph)C(NH(2))=NPh}(2)](Cl)(2), [2](Cl)(2), were crystallized from MeNO(2)-containing systems providing nitromethane solvates studied by X-ray diffraction. In the crystal structure of [1][(Hal)(2)(MeNO(2))(2)] (Hal = Cl, Br, I) and [2][(Cl)(2)(MeNO(2))(2)], the solvated MeNO(2) molecules occupy vacant spaces between lasagna-type layers and connect to the Hal(-) ion through a weak hydrogen bridge via the H atom of the methyl thus forming, by means of the Hal(-)···HCH(2)NO(2) contact, the halide-nitromethane cluster "filling". The quantum-chemical calculations demonstrated that the short distance between the Hal(-) anion and the hydrogen atom of nitromethane in clusters [1][(Hal)(2)(MeNO(2))(2)] and [2][(Cl)(2)(MeNO(2))(2)] is not just a consequence of the packing effect but a result of the moderately strong hydrogen bonding.

  8. Influence of the rate of conversion of HT and HTO on projected radiation doses from release of molecular tritium

    International Nuclear Information System (INIS)

    Jacobs, D.G.; Easterly, C.E.; Phillips, J.E.

    1979-01-01

    Releases of tritium in the past have been largely in the form of tritiated water, and the projected radiation doses could be estimated by assuming tritium behaviour to parallel that of water. There is increasing interest in potential releases of tritium in the form of HT because of significant recent advances in fusion reactor research. Several recent studies have shown that bacteria containing the enzyme hydrogenase can catalyse the conversion of HT to HTO at rates several orders of magnitude faster than the rates measured in atmospheric systems. Rates of conversion in the soil have been combined with estimates of rates of permeation of HT into the soil and with global and local models depicting tritium transport and cycling. The results suggest that for the expected conversion rates, the impact on projected radiation doses should be relatively minor. (author)

  9. Spin-Orbit Effect on the Molecular Properties of TeXn (X = F, Cl, Br, and I; n = 1, 2, and 4): A Density Functional Theory and Ab Initio Study.

    Science.gov (United States)

    Moon, Jiwon; Kim, Joonghan

    2016-09-29

    Density functional theory (DFT) and ab initio calculations, including spin-orbit coupling (SOC), were performed to investigate the spin-orbit (SO) effect on the molecular properties of tellurium halides, TeXn (X = F, Cl, Br, and I; n = 1, 2, and 4). SOC elongates the Te-X bond and slightly reduces the vibrational frequencies. Consideration of SOC leads to better agreement with experimental values. Møller-Plesset second-order perturbation theory (MP2) seriously underestimates the Te-X bond lengths. In contrast, B3LYP significantly overestimates them. SO-PBE0 and multireference configuration interactions with the Davidson correction (MRCI+Q), which include SOC via a state-interaction approach, give the Te-I bond length of TeI2 that matches the experimental value. On the basis of the calculated thermochemical energy and optimized molecular structure, TeI4 is unlikely to be stable. The use of PBE0 including SOC is strongly recommended for predicting the molecular properties of Te-containing compounds.

  10. Activation energies of the self-diffusion of HTO, 22Na+ and 36Cl- in a highly compacted argillaceous rock (Opalinus Clay)

    International Nuclear Information System (INIS)

    Loon, L.R. van; Mueller, W.; Iijima, K.

    2005-01-01

    The temperature dependence of the self-diffusion of HTO, 22 Na + and 36 Cl - in Opalinus Clay (OPA) was studied using a through-diffusion technique, in which the temperature was gradually increased in the steady state phase of the diffusion. The measurements were done on samples from two different geological locations. The dependence of the effective diffusion coefficient on temperature was found to be of an Arrhenius type in the temperature range between 0 and 70 deg. C. A slight difference between the two locations could be observed. The average value of the activation energy of the self-diffusion of HTO in OPA was 21.1 ± 1.6 kJ mol -1 , and 21.0 ± 3.5 and 19.4 ± 1.5 kJ mol -1 for 22 Na + and 36 Cl - , respectively. The measured values for HTO are slightly higher than the values found for the bulk liquid water (HTO: 18.8 ± 0.4 kJ mol -1 ). This indicates that the structure of the confined water in OPA might be slightly different from that of bulk liquid water. Also for Na + and Cl - , slightly higher values than in bulk liquid water (Na + : 18.4 kJ mol -1 ; Cl - : 17.4 kJ mol -1 ) were observed. The Stokes-Einstein relationship, based on the temperature dependency of the viscosity of bulk water, could not be used to describe the temperature dependence of the diffusion of HTO in OPA. This additionally indicates the slightly different structure of the pore water in OPA

  11. BR15-Værktøj

    DEFF Research Database (Denmark)

    2016-01-01

    BR15 Værktøjet giver svar på hovedparten af de problemstillinger håndværkere og entreprenører støder på i anvendelsen af det nye Bygningsreglement i forbindelse med renoveringsopgaver. Værktøjet er let, praktisk og overskueligt, og du kan ved hjælp af alfabetiske lister over bygningsdele og...

  12. Postsynthesis Transformation of Insulating Cs4PbBr6 Nanocrystals into Bright Perovskite CsPbBr3 through Physical and Chemical Extraction of CsBr.

    Science.gov (United States)

    Palazon, Francisco; Urso, Carmine; De Trizio, Luca; Akkerman, Quinten; Marras, Sergio; Locardi, Federico; Nelli, Ilaria; Ferretti, Maurizio; Prato, Mirko; Manna, Liberato

    2017-10-13

    Perovskite-related Cs 4 PbBr 6 nanocrystals present a "zero-dimensional" crystalline structure where adjacent [PbBr 6 ] 4- octahedra do not share any corners. We show in this work that these nanocrystals can be converted into "three-dimensional" CsPbBr 3 perovskites by extraction of CsBr. This conversion drastically changes the optoelectronic properties of the nanocrystals that become highly photoluminescent. The extraction of CsBr can be achieved either by thermal annealing (physical approach) or by chemical reaction with Prussian Blue (chemical approach). The former approach can be simply carried out on a dried film without addition of any chemicals but does not yield a full transformation. Instead, reaction with Prussian Blue in solution achieves a full transformation into the perovskite phase. This transformation was also verified on the iodide counterpart (Cs 4 PbI 6 ).

  13. Semiconducting perovskites (2-XC6H4C2H4NH3)2SnI4 (X = F, Cl, Br): steric interaction between the organic and inorganic layers.

    Science.gov (United States)

    Xu, Zhengtao; Mitzi, David B; Dimitrakopoulos, Christos D; Maxcy, Karen R

    2003-03-24

    Two new semiconducting hybrid perovskites based on 2-substituted phenethylammonium cations, (2-XC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) (X = Br, Cl), are characterized and compared with the previously reported X = F compound, with a focus on the steric interaction between the organic and inorganic components. The crystal structure of (2-ClC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) is solved in a disordered subcell [C2/m, a = 33.781(7) A, b = 6.178(1) A, c = 6.190(1) A, beta = 90.42(3)(o), and Z = 2]. The structure is similar to the known (2-FC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) structure with regard to both the conformation of the organic cations and the bonding features of the inorganic sheet. The (2-BrC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) system adopts a fully ordered monoclinic cell [P2(1)/c, a = 18.540(2) A, b = 8.3443(7) A, c = 8.7795(7) A, beta = 93.039(1)(o), and Z = 2]. The organic cation adopts the anti conformation, instead of the gauche conformation observed in the X = F and Cl compounds, apparently because of the need to accommodate the additional volume of the bromo group. The steric effect of the bromo group also impacts the perovskite sheet, causing notable distortions, such as a compressed Sn-I-Sn bond angle (148.7(o), as compared with the average values of 153.3 and 154.8(o) for the fluoro and chloro compounds, respectively). The optical absorption features a substantial blue shift (lowest exciton peak: 557 nm, 2.23 eV) relative to the spectra of the fluoro and chloro compounds (588 and 586 nm, respectively). Also presented are transport properties for thin-film field-effect transistors (TFTs) based on spin-coated films of the two hybrid semiconductors.

  14. The motley family of polar compounds (MV)[M(X{sub 5-x}X Prime {sub x})] based on anionic chains of trans-connected M{sup (III)}(X,X Prime ){sub 6} octahedra (M=Bi, Sb; X, X Prime =Cl, Br, I) and methylviologen (MV) dications

    Energy Technology Data Exchange (ETDEWEB)

    Leblanc, Nicolas [Laboratoire MOLTECH-Anjou, UMR-CNRS 6200, Universite d' Angers 2 Bd Lavoisier, 49045 Angers (France); Mercier, Nicolas, E-mail: nicolas.mercier@univ-angers.fr [Laboratoire MOLTECH-Anjou, UMR-CNRS 6200, Universite d' Angers 2 Bd Lavoisier, 49045 Angers (France); Allain, Magali; Toma, Oksana [Laboratoire MOLTECH-Anjou, UMR-CNRS 6200, Universite d' Angers 2 Bd Lavoisier, 49045 Angers (France); Auban-Senzier, Pascale; Pasquier, Claude [Laboratoire de Physique des Solides, UMR-CNRS 8502, Bat. 510,Universite Paris Sud, 91405 Orsay (France)

    2012-11-15

    The search for hybrid organic-inorganic materials remains a great challenge in the field of ferroelectrics. Following the discovery of the room temperature ferroelectric material (MV)[BiI{sub 3}Cl{sub 2}] (MV{sup 2+}: methylviologen) exhibiting the highest polarization value in the field of hybrid ferroelectrics, we report here nine new hybrids with the general formulation (MV)[M{sup (III)}X{sub 5-x}X Prime {sub x}] (M=Bi, Sb; X, X Prime =Cl, Br, I): (MV)[BiCl{sub 3.3}Br{sub 1.7}] (1), (MV)[BiCl{sub 1.3}Br{sub 3.7}] (2), (MV)[BiBr{sub 3.2}I{sub 1.8}] (3), (MV)[SbCl{sub 5}] (4), (MV)[SbBr{sub 5}] (5), (MV)[SbCl{sub 3.8}Br{sub 1.2}] (6), (MV)[SbCl{sub 2.4}Br{sub 2.6}] (7), (MV)[SbI{sub 3}Cl{sub 2}] (8) and (MV)[SbBr{sub 3.8}I{sub 1.2}] (9). Depending on the presence of polar chains or not, and on the coupling of polar chains, two types of centrosymmetrical structures [C1] and [C2] and two types of polar structures [P1] and [P2] are defined. (2) undergoes a paraelectric-to-relaxor ferroelectric transition around 100-150 K depending of the frequency showing that the Curie temperature, T{sub C}, of (MV)[BiBr{sub 5}] (243 K) can be modulated by the substitution of Br by Cl. The most interesting family is the [P2] type because the syn coupling of polar chains is in favor of high polarization values, as in (MV)[BiI{sub 3}Cl{sub 2}]. Five of the nine new hybrids, (4), (6-9), which have the [P2] type structure are potential ferroelectrics. - Graphical abstract: The methylviologen haloantimonate (MV)[SbX{sub 5-x}X Prime {sub x}] families (X, X Prime =Cl, Br, I) - [P1] and [P2] are the two kinds of polar structures - and view of the (MV)[SbBr{sub 3.8}I{sub 1.2}] hybrid based on chiral polar chains which are in syn coupling. Highlights: Black-Right-Pointing-Pointer Nine hybrids based on methylviologen and halometalate chains have been discovered. Black-Right-Pointing-Pointer The polar nature of chains is due to the ns{sup 2} stereoactivity of Sb{sup (III)} or Bi{sup (III

  15. Izlaganje na javni uvid podataka o nekretninama i utvrđivanje prava na zemljištu u funkciji uspostave jedinstvenog registra zemljišta i prava na zemljištu u Brčko distriktu BiH : Public presentation of data on real-estate and determination of rights in function of the establishment of a single registry of real-estate and real rights to real-estate in the Brcko district of B&H

    Directory of Open Access Journals (Sweden)

    Faruk Latifović

    2014-12-01

    Full Text Available Zakon o registru zemljišta i prava na zemljištu Brčko distrikta Bosne i Hercegovine je propisao uspostavu jedinstvene evidencije nekretnina i stvarnih prava na nekretninama u Brčko distriktu Bosne i Hercegovine. Poslovi uspostave jedinstvene evidencije, u segmentu izlaganja na javni uvid podataka o nekretninama i utvrđivanje prava, su povjereni Vijeću za izlaganje podataka o nekretninama i utvrđivanje prava na zemljištu Brčko distrikta Bosne i Hercegovine. Autor se, u ovom radu, uz nezaobilazan kraći prikaz historijata javnih evidencija na nekretninama u Bosni i Hercegovini, bavi organizacijom, nadležnostima i načinom rada Vijeća za izlaganje podataka o nekretninama i utvrđivanje prava na zemljištu Brčko distrikta BIH. Nakon što bude uspješno okončan projekat izlaganje podataka o nekretninama i utvrđivanje prava na zemljištu u Brčko distriktu BiH, svi geodetsko – katastarski podaci o nepokretnostima kao i podaci o njihovom pravnom statusu će biti vođeni u Registru zemljišta i prava na zemljištu Osnovnog suda Brčko distrikta BiH. : The Law of Land Registry and Rights over Land of the Brčko District of B&H stipulated the establishment of a single registry of real-estate and real rights to real-estate in the Brčko District of B&H. Activities of the establishment of a single registry, in the segment of public presentation of data on real-estate and determination of rights, were entrusted to the Council for Presentation of Data on Real-estate and Establishment of Rights to Land of the Brčko District of B&H. In this paper, the author presents the inevitable short overview of the history of real-estate registries in Bosnia and Herzegovina and he also deals with organization, competencies and manner of work of the Council for Presentation of Data on Real-estate and Establishment of Rights to Land of the Brčko District of B&H. After a successful completion of the project of presentation of data on real-estate and

  16. BR2 Reactor: Introduction

    International Nuclear Information System (INIS)

    Moons, F.

    2007-01-01

    The irradiations in the BR2 reactor are in collaboration with or at the request of third parties such as the European Commission, the IAEA, research centres and utilities, reactor vendors or fuel manufacturers. The reactor also contributes significantly to the production of radioisotopes for medical and industrial applications, to neutron silicon doping for the semiconductor industry and to scientific irradiations for universities. Along the ongoing programmes on fuel and materials development, several new irradiation devices are in use or in design. Amongst others a loop providing enhanced cooling for novel materials testing reactor fuel, a device for high temperature gas cooled fuel as well as a rig for the irradiation of metallurgical samples in a Pb-Bi environment. A full scale 3-D heterogeneous model of BR2 is available. The model describes the real hyperbolic arrangement of the reactor and includes the detailed 3-D space dependent distribution of the isotopic fuel depletion in the fuel elements. The model is validated on the reactivity measurements of several tens of BR2 operation cycles. The accurate calculations of the axial and radial distributions of the poisoning of the beryllium matrix by 3 He, 6 Li and 3T are verified on the measured reactivity losses used to predict the reactivity behavior for the coming decades. The model calculates the main functionals in reactor physics like: conventional thermal and equivalent fission neutron fluxes, number of displacements per atom, fission rate, thermal power characteristics as heat flux and linear power density, neutron/gamma heating, determination of the fission energy deposited in fuel plates/rods, neutron multiplication factor and fuel burn-up. For each reactor irradiation project, a detailed geometry model of the experimental device and of its neighborhood is developed. Neutron fluxes are predicted within approximately 10 percent in comparison with the dosimetry measurements. Fission rate, heat flux and

  17. Temperature dependent absorption spectra of Br(-), Br2(•-), and Br3(-) in aqueous solutions.

    Science.gov (United States)

    Lin, Mingzhang; Archirel, Pierre; Van-Oanh, Nguyen Thi; Muroya, Yusa; Fu, Haiying; Yan, Yu; Nagaishi, Ryuji; Kumagai, Yuta; Katsumura, Yosuke; Mostafavi, Mehran

    2011-05-05

    The absorption spectra of Br(2)(•-) and Br(3)(-) in aqueous solutions are investigated by pulse radiolysis techniques from room temperature to 380 and 350 °C, respectively. Br(2)(•-) can be observed even in supercritical conditions, showing that this species could be used as a probe in pulse radiolysis at high temperature and even under supercritical conditions. The weak temperature effect on the absorption spectra of Br(2)(•-) and Br(3)(-) is because, in these two systems, the transition occurs between two valence states; for example, for Br(2)(-) we have (2)Σ(u) → (2)Σ(g) transition. These valence transitions involve no diffuse final state. However, the absorption band of Br(-) undergoes an important red shift to longer wavelengths. We performed classical dynamics of hydrated Br(-) system at 20 and 300 °C under pressure of 25 MPa. The radial distribution functions (rdf's) show that the strong temperature increase (from 20 to 300 °C) does not change the radius of the solvent first shell. On the other hand, it shifts dramatically (by 1 Å) the second maximum of the Br-O rdf and introduces much disorder. This shows that the first water shell is strongly bound to the anion whatever the temperature. The first two water shells form a cavity of a roughly spherical shape around the anion. By TDDFT method, we calculated the absorption spectra of hydrated Br(-) at two temperatures and we compared the results with the experimental data.

  18. Core-dependent and ligand-dependent relativistic corrections to the nuclear magnetic shieldings in MH4-n Y n (n = 0-4; M = Si, Ge, Sn, and Y = H, F, Cl, Br, I) model compounds.

    Science.gov (United States)

    Maldonado, Alejandro F; Aucar, Gustavo A; Melo, Juan I

    2014-09-01

    The nuclear magnetic shieldings of Si, Ge, and Sn in MH(4-n) Y(n) (M = Si, Ge, Sn; Y = F, Cl, Br, I and n = 1-4) molecular systems are highly influenced by the substitution of one or more hydrogens by heavy-halogen atoms. We applied the linear response elimination of small components (LRESC) formalism to calculate those shieldings and learn whether including only a few of the leading relativistic correction terms is sufficient to be able to quantitatively reproduce the full relativistic value. It was observed that the nuclear magnetic shieldings change as the number of heavy halogen substituents and their weights vary, and the pattern of σ(M) generally does not exhibit the normal halogen dependence (NHD) behavior that can be seen in similar molecular systems containing carbon atoms. We also analyzed each relativistic correction afforded by the LRESC method and split them in two: core-dependent and ligand-dependent contributions; we then looked for the electronic mechanisms involved in the different relativistic effects and in the total relativistic value. Based on this analysis, we were able to study the electronic mechanism involved in a recently proposed relativistic effect, the "heavy atom effect on vicinal heavy atom" (HAVHA), in more detail. We found that the main electronic mechanism is the spin-orbit or σ p (T(3)) correction, although other corrections such as σ p (S(1)) and σ p (S(3)) are also important. Finally, we analyzed proton magnetic shieldings and found that, for molecules containing Sn as the central atom, σ(H) decreases as the number of heavy halogen substituents (of the same type: either F, Cl, or Br) increases, albeit at different rates for different halogens. σ(H) only increase as the number of halogen substituents increases if the halogen is iodine.

  19. Pathways for the OH + Br2 → HOBr + Br and HOBr + Br → HBr + BrO Reactions.

    Science.gov (United States)

    Wang, Hongyan; Qiu, Yudong; Schaefer, Henry F

    2016-02-11

    The OH radical reaction with Br2 and the subsequent reaction HOBr + Br are of exceptional importance to atmospheric chemistry and environmental chemistry. The entrance complex, transition state, and exit complex for both reactions have been determined using the coupled-cluster method with single, double, and perturbative triple excitations CCSD(T) with correlation consistent basis sets up to size cc-pV5Z and cc-pV5Z-PP. Coupled cluster effects with full triples (CCSDT) and full quadruples (CCSDTQ) are explicitly investigated. Scalar relativistic effects, spin-orbit coupling, and zero-point vibrational energy corrections are evaluated. The results from the all-electron basis sets are compared with those from the effective core potential (ECP) pseudopotential (PP) basis sets. The results are consistent. The OH + Br2 reaction is predicted to be exothermic 4.1 ± 0.5 kcal/mol, compared to experiment, 3.9 ± 0.2 kcal/mol. The entrance complex HO···BrBr is bound by 2.2 ± 0.2 kcal/mol. The transition state lies similarly well below the reactants OH + Br2. The exit complex HOBr···Br is bound by 2.7 ± 0.6 kcal/mol relative to separated HOBr + Br. The endothermicity of the reaction HOBr + Br → HBr + BrO is 9.6 ± 0.7 kcal/mol, compared with experiment 8.7 ± 0.3 kcal/mol. For the more important reverse (exothermic) HBr + BrO reaction, the entrance complex BrO···HBr is bound by 1.8 ± 0.6 kcal/mol. The barrier for the HBr + BrO reaction is 6.8 ± 0.9 kcal/mol. The exit complex (Br···HOBr) for the HBr + BrO reaction is bound by 1.9 ± 0.2 kcal/mol with respect to the products HOBr + Br.

  20. Ammonium dynamics in the disordered α-phase of K1-x(NH4)xY (Y = Cl, Br, I). A neutron scattering study

    International Nuclear Information System (INIS)

    Natkaniec, I.; Smirnov, L.S.; Shuvalov, L.A.

    2002-01-01

    The effect of temperature and concentration on the lattice parameters and amplitude-weighted phonon density of states in mixed salts of ammonium-potassium halides is investigated by neutron powder diffraction and incoherent inelastic neutron scattering. In the disordered α-phase (NaCl type) ammonium ions exhibit a fast stochastic reorientation at phonon frequency rates down to ca. 80 K. At 10 K, the incoherent inelastic neutron scattering spectra display four distinct ammonium excitations: two (resonant) modes below and two (localized) above the Debye cut-off energy of potassium halides. High-frequency localized modes correspond to translational and librational vibrations of NH 4 ions. These modes are typical for the ordered phases of ammonium halides. The effect of ammonium concentration on localized and resonant modes is studied for the K 1-x (NH 4 ) x I mixed salts. The harmonic excitations of ammonium in a hypothetical low-temperature α-phase of NH 4 I are approximated to ca. 30, 95, 155 and 250 cm -1 . In a real low-temperature ordered γ-phase of NH 4 I, translational ammonium vibrations are observed at ca. 140-160 cm -1 and librational vibrations at ca.300 cm -1

  1. Exploring Polaronic, Excitonic Structures and Luminescence in Cs4PbBr6/CsPbBr3.

    Science.gov (United States)

    Kang, Byungkyun; Biswas, Koushik

    2018-02-15

    Among the important family of halide perovskites, one particular case of all-inorganic, 0-D Cs 4 PbBr 6 and 3-D CsPbBr 3 -based nanostructures and thin films is witnessing intense activity due to ultrafast luminescence with high quantum yield. To understand their emissive behavior, we use hybrid density functional calculations to first compare the ground-state electronic structure of the two prospective compounds. The dispersive band edges of CsPbBr 3 do not support self-trapped carriers, which agrees with reports of weak exciton binding energy and high photocurrent. The larger gap 0-D material Cs 4 PbBr 6 , however, reveals polaronic and excitonic features. We show that those lattice-coupled carriers are likely responsible for observed ultraviolet emission around ∼375 nm, reported in bulk Cs 4 PbBr 6 and Cs 4 PbBr 6 /CsPbBr 3 composites. Ionization potential calculations and estimates of type-I band alignment support the notion of quantum confinement leading to fast, green emission from CsPbBr 3 nanostructures embedded in Cs 4 PbBr 6 .

  2. Tunable CsPbBr3/Cs4PbBr6 phase transformation and their optical spectroscopic properties.

    Science.gov (United States)

    Chen, Xiao; Chen, Daqin; Li, Junni; Fang, Gaoliang; Sheng, Hongchao; Zhong, Jiasong

    2018-04-24

    As a novel type of promising materials, metal halide perovskites are a rising star in the field of optoelectronics. On this basis, a new frontier of zero-dimensional perovskite-related Cs4PbBr6 with bright green emission and high stability has attracted an enormous amount of attention, even though its photoluminescence still requires to clarification. Herein, the controllable phase transformation between three-dimensional CsPbBr3 and zero-dimensional Cs4PbBr6 is easily achieved in a facile ligand-assisted supersaturated recrystallization synthesis procedure via tuning the amount of surfactants, and their unique optical properties are investigated and compared in detail. Both Cs4PbBr6 and CsPbBr3 produce remarkably intense green luminescence with quantum yields up to 45% and 80%, respectively; however, significantly different emitting behaviors are observed. The fluorescence lifetime of Cs4PbBr6 is much longer than that of CsPbBr3, and photo-blinking is easily detected in the Cs4PbBr6 product, proving that the zero-dimensional Cs4PbBr6 is indeed a highly luminescent perovskite-related material. Additionally, for the first time, tunable emissions over the visible-light spectral region are demonstrated to be achievable via halogen composition modulations in the Cs4PbX6 (X = Cl, Br, I) samples. Our study brings a simple method for the phase control of CsPbBr3/Cs4PbBr6 and demonstrates the intrinsic luminescence nature of the zero-dimensional perovskite-related Cs4PbX6 products.

  3. RESONANCE CARS IN BR2 MOLECULES AND BR-ATOMS

    NARCIS (Netherlands)

    Aben, I.; Levelt, P.; Ubachs, W.M.G.; Hogervorst, W.

    1991-01-01

    Resonance-enhanced CARS processes were studied in molecular bromine. On the basis of the known spectroscopic constants of the two electronic states involved, the features in the spectra could be identified. CARS signals from Br-atoms produced from dissociation of Br2 were obtained by tuning (omega-1

  4. Polymorphism in Br2 clathrate hydrates.

    Science.gov (United States)

    Goldschleger, I U; Kerenskaya, G; Janda, K C; Apkarian, V A

    2008-02-07

    The structure and composition of bromine clathrate hydrate has been controversial for more than 170 years due to the large variation of its observed stoichiometries. Several different crystal structures were proposed before 1997 when Udachin et al. (Udachin, K. A.; Enright, G. D.; Ratcliffe, C. I.; Ripmeester, J. A. J. Am. Chem. Soc. 1997, 119, 11481) concluded that Br2 forms only the tetragonal structure (TS-I). We show polymorphism in Br2 clathrate hydrates by identifying two distinct crystal structures through optical microscopy and resonant Raman spectroscopy on single crystals. After growing TS-I crystals from a liquid bromine-water solution, upon dropping the temperature slightly below -7 degrees C, new crystals of cubic morphology form. The new crystals, which have a limited thermal stability range, are assigned to the CS-II structure. The two structures are clearly distinguished by the resonant Raman spectra of the enclathrated Br2, which show long overtone progressions and allow the extraction of accurate vibrational parameters: omega(e) = 321.2 +/- 0.1 cm(-1) and omega(e)x(e) = 0.82 +/- 0.05 cm(-1) in TS-I and omega(e) = 317.5 +/- 0.1 cm(-1) and omega(e)x(e) = 0.70 +/- 0.1 cm(-1) in CS-II. On the basis of structural analysis, the discovery of the CS-II crystals implies stability of a large class of bromine hydrate structures and, therefore, polymorphism.

  5. The genus Actiniceps Berk. & Br

    NARCIS (Netherlands)

    Boedijn, K.B.

    1959-01-01

    The genus Actiniceps Berk. & Br. is shown to be a Basidiomycete. Wiesnerina Höhn. and Dimorphocystis Corner are regarded synonymous. The type species A. thwaitesii Berk. & Br. is redescribed with D. capitatus Corner as synonym. The following new combinations are proposed: A. horrida (Höhn.) Boedijn,

  6. Thermodynamic assessment of EuBr2 unary and LiBr-EuBr2 and NaBr-EuBr2 binary systems

    International Nuclear Information System (INIS)

    Gong, Weiping; Gaune-Escard, Marcelle

    2009-01-01

    As a basis for the design and development of molten salt mixtures, thermodynamic calculations of the phase diagrams and thermodynamic properties were carried out on the EuBr 2 unary and LiBr-EuBr 2 and NaBr-EuBr 2 binary systems over a wide temperature and composition range, respectively. The Gibbs energy of EuBr 2 was evaluated using an independent polynomial to fit the experimental heat capacity, the thermodynamic parameters for each phase in the LiBr-EuBr 2 and NaBr-EuBr 2 systems were optimized by using available experimental information on phase diagrams. A regular substitutional solution model for the liquid phase and Neumann-Kopp rule for the stoichiometric compound LiEu 2 Br 5 were adopted to reproduce the experimental data with reasonable excess Gibbs energy. Comparisons between the calculated phase diagrams and thermodynamic quantities show that all reliable experimental information is satisfactorily accounted for by the present thermodynamic description. Some thermodynamic properties were predicted to check the suitability of the present calculation.

  7. Production of DNA Double Strand Breaks in Human Cells due to Acute Exposure to Tritiated Water (HTO)

    International Nuclear Information System (INIS)

    Gonen, R.; German, U.; Alfassi, Z. B.; Priel, E.

    2014-01-01

    The average and maximum energies of the beta emission from 3H are 5.69 keV and 18.6 keV respectively. The average range in water (or soft tissues), around 0.5 1/4m (500 nm), is considerably less than the typical diameter of a cell (10-30 1/4m), and even of a cell nucleus (5-10 1/4m), thus the micro-location of the tritium atom may well be crucial in determining its biochemical consequences. Due to the high ionization density of the beta particles emitted by tritium (about 400 ion pairs/1/4m) possible interaction of tritium beta radiation with DNA may play a significant role. Tritiated water (HTO) is the main chemical form in which tritium is found in the environment. In the body it may be retained as organically bound tritium (OBT), binding to biological molecules or remaining as OBT with various degrees of solubility. OBT can be retained in the human body much longer than HTO and therefore the dose arising from OBT can reach 50% of the total tritium dose . Histones are major protein components of chromatin. They function as spools around which DNA winds and play an important role in the regulation of gene expression. In the absence of histones, the DNA in chromosomes would be unmanageably long, as human cells each have about 1.8 m of DNA. During mitosis, DNA is duplicated and condensed, resulting in about 120 1/4m of chromosomes. It was recently reported that the phosphorylation of histone H2AX on serine residue 139 (D 3 -H2AX) is associated with Double Strand Breaks (DSB) sites in DNA), which indicates the possibility of research based on the detection of DSBs in DNA. The phosphorylated megabase chromatin domain surrounding the DSB can be immunostained and visualized as discrete foci by fluorescence microscopy, as each DNA DSB formed produces a visible D 3 -H2AX focus. Since 1 Gy of radiation produces approximately 60 DSBs/cell, doses of a few mGy should be distinguishable from the background, and it was recently shown that the exposure to 1 mGy of X-rays induces

  8. Majandus- või kutsetegevuses tegutseva isiku kaitse tarbija hagemisel Brüsseli I määruse tarbijalepinguid reguleerivate sätete alusel : [magistritöö] / Riin Rehepapp ; Tartu Ülikool, õigusteaduskond ; juhendaja: Maarja Torga

    Index Scriptorium Estoniae

    Rehepapp, Riin, 1987-

    2013-01-01

    Pooltest Brüssel I määruse 4. jaos sätestatud tarbijalepingutes, majandus- või kutsetegevuses tegutseva isiku kaitsest tarbija hagemisel üldisel ja erialusel määratud kohtus või poolte kokkuleppega määratud kohtus

  9. Synthesis, vibrational and optical properties of a new three-layered organic-inorganic perovskite (C{sub 4}H{sub 9}NH{sub 3}){sub 4}Pb{sub 3}I{sub 4}Br{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Dammak, T., E-mail: thameurlpa@yahoo.f [Laboratoire de Physique appliquee (LPA), Faculte des Sciences de Sfax, 3018, BP 802 (Tunisia); Elleuch, S. [Laboratoire de Physique appliquee (LPA), Faculte des Sciences de Sfax, 3018, BP 802 (Tunisia); Bougzhala, H. [Laboratoire de cristallochimie et des materiaux, Faculte des Sciences de Tunis (Tunisia); Mlayah, A. [Centre d' Elaboration de Materiaux et d' Etudes Structurales, CNRS-Universite Paul Sabatier, 29 rue Jeanne Marvig, 31055 Toulouse, Cedex 4 (France); Chtourou, R. [Centre de Recherche et des Technologies de l' Energie CRTEn BP. 95, Hammam-Lif 2050, Laboratoire de Photovoltaique et de Semiconducteur (Tunisia); Abid, Y. [Laboratoire de Physique appliquee (LPA), Faculte des Sciences de Sfax, 3018, BP 802 (Tunisia)

    2009-09-15

    An organic-inorganic hybrid perovskite (C{sub 4}H{sub 9}NH{sub 3}){sub 4}Pb{sub 3}I{sub 4}Br{sub 6} was synthesized and studied by X-ray diffraction, Raman and infrared spectroscopies, optical transmission and photoluminescence. The title compound, abbreviated (C{sub 4}){sub 4}Pb{sub 3}I{sub 4}Br{sub 6}, crystallises in a periodic two-dimensional multilayer structure with P2{sub 1}/a space group. The structure is built up from alternating inorganic and organic layers. Each inorganic layer consists of three sheets of PbX{sub 6} (X=I, Br) octahedra. Raman and infrared spectra of the title compound were recorded in the 100-3500 and 400-4000 cm{sup -1} frequency ranges, respectively. An assignment of the observed vibration modes is reported. Optical transmission measurements, performed on thin films of (C{sub 4}){sub 4}Pb{sub 3}I{sub 4}Br{sub 6}, revealed two absorption bands at 474 and 508 nm. Photoluminescence measurements have shown a green emission peak at 519 nm.

  10. No solid solution compounds in between the binaries. Syntheses and crystal structures of Nb(Br{sub 0.62(4)}Cl{sub 0.38(4)}){sub 2}Cl{sub 2} and NbI{sub 2}Cl{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Reckeweg, Olaf; Schleid, Thomas [Stuttgart Univ. (Germany). Inst. fuer Anorganische Chemie

    2018-04-01

    The anion-mixed niobium tetrahalides Nb(Br{sub 0.62(4)}Cl{sub 0.38(4)}){sub 2}Cl{sub 2} and NbI{sub 2}Cl{sub 2} were obtained by heating NbBr{sub 5} with NbCl{sub 5} and NbI{sub 5} with NbCl{sub 5}, respectively, in equimolar ratios with niobium metal in evacuated, torch-sealed silica ampoules at 720 K for 3 days. The orthorhombic title compounds form as very brittle black needles and were characterized by single-crystal X-ray diffraction [space group: Immm, Z=4; a=704.27(6), b=824.13(7), c=929.64(8) pm for Nb(Br{sub 0.62(4)}Cl{sub 0.38(4)}){sub 2}Cl{sub 2} and a=753.76(6), b=829.38(7) and c=983.41(8) pm for NbI{sub 2}Cl{sub 2}]. Surprisingly enough, these mixed-anionic halides are not isostructural with either NbCl{sub 4}, NbBr{sub 4} or NbI{sub 4}, but crystallize isotypically with TaI{sub 2}Cl{sub 2}, thus being examples for differential site occupancy stabilized materials. Structural features of other niobium(IV) halides are compiled and compared to those of Nb(Br{sub 0.62(4)}Cl{sub 0.38(4)}){sub 2}Cl{sub 2} and NbI{sub 2}Cl{sub 2}. Except for NbF{sub 4}, they all exhibit chains of trans-edge connected [NbX{sub 6}]{sup 2-} octahedra, which allow Peierls distortions to form Nb-Nb single bonds. The packing of these chains differ, however, depending on the actual halide or mixed-halide combination.

  11. Absolute NMR shielding scales and nuclear spin–rotation constants in {sup 175}LuX and {sup 197}AuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br and {sup 127}I)

    Energy Technology Data Exchange (ETDEWEB)

    Demissie, Taye B., E-mail: taye.b.demissie@uit.no; Komorovsky, Stanislav; Repisky, Michal; Ruud, Kenneth [Centre for Theoretical and Computational Chemistry, Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø (Norway); Jaszuński, Michał [Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01 224 Warszawa (Poland)

    2015-10-28

    We present nuclear spin–rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants, and shielding spans of all the nuclei in {sup 175}LuX and {sup 197}AuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br, {sup 127}I), calculated using coupled-cluster singles-and-doubles with a perturbative triples (CCSD(T)) correction theory, four-component relativistic density functional theory (relativistic DFT), and non-relativistic DFT. The total nuclear spin–rotation constants determined by adding the relativistic corrections obtained from DFT calculations to the CCSD(T) values are in general in agreement with available experimental data, indicating that the computational approach followed in this study allows us to predict reliable results for the unknown spin–rotation constants in these molecules. The total NMR absolute shielding constants are determined for all the nuclei following the same approach as that applied for the nuclear spin–rotation constants. In most of the molecules, relativistic effects significantly change the computed shielding constants, demonstrating that straightforward application of the non-relativistic formula relating the electronic contribution to the nuclear spin–rotation constants and the paramagnetic contribution to the shielding constants does not yield correct results. We also analyze the origin of the unusually large absolute shielding constant and its relativistic correction of gold in AuF compared to the other gold monohalides.

  12. Calibration setting numbers for dose calibrators for the PET isotopes "5"2Mn, "6"4Cu, "7"6Br, "8"6Y, "8"9Zr, "1"2"4I

    International Nuclear Information System (INIS)

    Wooten, A. Lake; Lewis, Benjamin C.; Szatkowski, Daniel J.; Sultan, Deborah H.; Abdin, Kinda I.; Voller, Thomas F.; Liu, Yongjian; Lapi, Suzanne E.

    2016-01-01

    For PET radionuclides, the radioactivity of a sample can be conveniently measured by a dose calibrator. These devices depend on a “calibration setting number”, but many recommended settings from manuals were interpolated based on standard sources of other radionuclide(s). We conducted HPGe gamma-ray spectroscopy, resulting in a reference for determining settings in two types of vessels containing one of several PET radionuclides. Our results reiterate the notion that in-house, experimental calibrations are recommended for different radionuclides and vessels. - Highlights: • Dose calibrators measure radioactivity by ionization of gas from emitted radiation. • Accuracy of dose calibrators depends on “calibration setting numbers” for isotopes. • Many manufacturer settings are interpolated from emissions of other radionuclides. • As a high-precision reference, HPGe gamma-ray spectroscopy was conducted. • New calibrations were found for PET isotopes "5"2Mn, "6"4Cu, "7"6Br, "8"6Y, "8"9Zr, and "1"2"4I.

  13. Lattice and Valence Electronic Structures of Crystalline Octahedral Molybdenum Halide Clusters-Based Compounds, Cs2[Mo6X14] (X = Cl, Br, I), Studied by Density Functional Theory Calculations.

    Science.gov (United States)

    Saito, Norio; Cordier, Stéphane; Lemoine, Pierric; Ohsawa, Takeo; Wada, Yoshiki; Grasset, Fabien; Cross, Jeffrey S; Ohashi, Naoki

    2017-06-05

    The electronic and crystal structures of Cs 2 [Mo 6 X 14 ] (X = Cl, Br, I) cluster-based compounds were investigated by density functional theory (DFT) simulations and experimental methods such as powder X-ray diffraction, ultraviolet-visible spectroscopy, and X-ray photoemission spectroscopy (XPS). The experimentally determined lattice parameters were in good agreement with theoretically optimized ones, indicating the usefulness of DFT calculations for the structural investigation of these clusters. The calculated band gaps of these compounds reproduced those experimentally determined by UV-vis reflectance within an error of a few tenths of an eV. Core-level XPS and effective charge analyses indicated bonding states of the halogens changed according to their sites. The XPS valence spectra were fairly well reproduced by simulations based on the projected electron density of states weighted with cross sections of Al K α , suggesting that DFT calculations can predict the electronic properties of metal-cluster-based crystals with good accuracy.

  14. BR2 reactor: medical and industrial applications

    International Nuclear Information System (INIS)

    Ponsard, B.

    2005-01-01

    The radioisotopes are produced for various applications in the nuclear medicine (diagnostic, therapy, palliation of metastatic bone pain), industry (radiography of welds, ...), agriculture (radiotracers, ...) and basic research. Due to the availability of high neutron fluxes (thermal neutron flux up to 10 15 n/cm 2 .s), the BR2 reactor is considered as a major facility through its contribution for a continuous supply of products such 99 Mo ( 99 mTc), 131 I, 133 Xe, 192 Ir, 186 Re, 153 Sm, 90 Y, 32 P, 188 W ( 188 Re), 203 Hg, 82 Br, 41 Ar, 125 I, 177 Lu, 89 Sr, 60 Co, 169 Yb, 147 Nd, and others. Neutron Transmutation Doped (NTD) silicon is produced for the semiconductor industry in the SIDONIE (Silicon Doping by Neutron Irradiation Experiment) facility, which is designed to continuously rotate and traverse the silicon through the neutron flux. These combined movements produce exceptional dopant homogeneity in batches of silicon measuring 4 and 5-inches in diameter by up to 750 mm in length. The main objectives of work performed were to provide a reliable and qualitative supply of radioisotopes and NTD-silicon to the customers in accordance with a quality system that has been certified to the requirements of the EN ISO 9001: 2000. This new Quality System Certificate has been obtained in November 2003 for the Production of radioisotopes for medical and industrial applications and the Production of Neutron Transmutation Doped (NTD) Silicon in the BR2 reactor

  15. Hybridization of Single Nanocrystals of Cs4PbBr6 and CsPbBr3

    OpenAIRE

    Weerd, Chris de; Lin, Junhao; Gomez, Leyre; Fujiwara, Yasufumi; Suenaga, Kazutomo; Gregorkiewicz, Tom

    2017-01-01

    Nanocrystals of all-inorganic cesium lead halide perovskites (CsPbX3, X = Cl, Br, I) feature high absorption and efficient narrow-band emission which renders them promising for future generation of photovoltaic and optoelectronic devices. Colloidal ensembles of these nanocrystals can be conveniently prepared by chemical synthesis. However, in the case of CsPbBr3, its synthesis can also yield nanocrystals of Cs4PbBr6 and the properties of the two are easily confused. Here, we investigate in de...

  16. Synthesis and Biological Evaluation of (S)-Amino-2-methyl-4-[(76)Br]bromo-3-(E)-butenoic Acid (BrVAIB) for Brain Tumor Imaging.

    Science.gov (United States)

    Burkemper, Jennifer L; Huang, Chaofeng; Li, Aixiao; Yuan, Liya; Rich, Keith; McConathy, Jonathan; Lapi, Suzanne E

    2015-11-12

    The novel compound, (S)-amino-2-methyl-4-[(76)Br]bromo-3-(E)-butenoic acid (BrVAIB, [(76)Br]5), was characterized against the known system A tracer, IVAIB ([(123)I]8). [(76)Br]5 was prepared in a 51% ± 19% radiochemical yield with high radiochemical purity (≥98%). The biological properties of [(76)Br]5 were compared with those of [(123)I]8. Results showed that [(76)Br]5 undergoes mixed amino acid transport by system A and system L transport, while [(123)I]8 had less uptake by system L. [(76)Br]5 demonstrated higher uptake than [(123)I]8 in DBT tumors 1 h after injection (3.7 ± 0.4% ID/g vs 1.5 ± 0.3% ID/g) and also showed higher uptake vs [(123)I]8 in normal brain. Small animal PET studies with [(76)Br]5 demonstrated good tumor visualization of intracranial DBTs up to 24 h with clearance from normal tissues. These results indicate that [(76)Br]5 is a promising PET tracer for brain tumor imaging and lead compound for a mixed system A and system L transport substrate.

  17. Kan lignin omdannes til flydende brændstof?

    DEFF Research Database (Denmark)

    Nielsen, Joachim Bachmann; Jensen, Anders; Felby, Claus

    2015-01-01

    Ved en solvolytisk omdannelse af plantematerialet lignin til et flydende brændstof behandles det ved høj temperatur og højt tryk i et passende opløsningsmiddel. En sådan proces kan gennemføres ikke-katalytisk og være med til at skabe flydende brændsler baseret på vedvarende energikilder. Her...

  18. Tunable White-Light Emission in Single-Cation-Templated Three-Layered 2D Perovskites (CH 3 CH 2 NH 3 ) 4 Pb 3 Br 10–<i>x> Cl <i>x>

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Lingling; Wu, Yilei; Stoumpos, Constantinos C.; Traore, Boubacar [Institut; Katan, Claudine [Institut; Even, Jacky [Fonctions; Wasielewski, Michael R.; Kanatzidis, Mercouri G.

    2017-08-16

    Two-dimensional (2D) hybrid halide perovskites come as a family (B)2(A)n-1PbnX3n+1 (B and A= cations; X= halide). These perovskites are promising semiconductors for solar cells and optoelectronic applications. Among the fascinating properties of these materials is white-light emission, which has been mostly observed in single-layered 2D lead bromide or chloride systems (n = 1), where the broad emission comes from the transient photoexcited states generated by self-trapped excitons (STEs) from structural distortion. Here we report a multilayered 2D perovskite (n = 3) exhibiting a tunable white-light emission. Ethylammonium (EA+) can stabilize the 2D perovskite structure in EA4Pb3Br10–xClx (x = 0, 2, 4, 6, 8, 9.5, and 10) with EA+ being both the A and B cations in this system. Because of the larger size of EA, these materials show a high distortion level in their inorganic structures, with EA4Pb3Cl10 having a much larger distortion than that of EA4Pb3Br10, which results in broadband white-light emission of EA4Pb3Cl10 in contrast to narrow blue emission of EA4Pb3Br10. The average lifetime of the series decreases gradually from the Cl end to the Br end, indicating that the larger distortion also prolongs the lifetime (more STE states). The band gap of EA4Pb3Br10–xClx ranges from 3.45 eV (x = 10) to 2.75 eV (x = 0), following Vegard’s law. First-principles density functional theory calculations (DFT) show that both EA4Pb3Cl10 and EA4Pb3Br10 are direct band gap semiconductors. The color rendering index (CRI) of the series improves from 66 (EA4Pb3Cl10) to 83 (EA4Pb3Br0.5Cl9.5), displaying high tunability and versatility of the

  19. Estimering af bilers brændstofforbrug ved brug af eksisterende GPS data

    DEFF Research Database (Denmark)

    Andersen, Ove; Lahrmann, Harry; Torp, Kristian

    2012-01-01

    GPS data opsamles i mange sammenhænge f.eks. for at finde køretider i vejnettet. I denne artikel vises, hvorledes eksisterende GPS data kan bruges til at estimere brændstofforbruget for en tur. En metode til at estimere brændstofforbruget for en enkelt tur generaliseres til at kunne estimere...

  20. Determination of molecular stopping cross section of {sup 12}C, {sup 16}O, {sup 28}Si, {sup 35}Cl, {sup 58}Ni, {sup 79}Br, and {sup 127}I in silicon nitride

    Energy Technology Data Exchange (ETDEWEB)

    Barradas, N.P., E-mail: nunoni@ctn.ist.utl.pt [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Unversidade de Lisboa, Estrada Nacional 10 ao km 139.7, 2695-066 Bobadela LRS (Portugal); Bergmaier, A. [Institut für Angewandte Physik und Messtechnik, Fakultät für Luft und Raumfahrttechnik, Werner-Heisenberg-Weg 39, D-85577 Neubiberg (Germany); Mizohata, K. [Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 University of Helsinki (Finland); Msimanga, M. [iThemba LABS Gauteng, National Research Foundation, Private Bag 11, WITS 2050, Johannesburg (South Africa); Department of Physics, Tshwane University of Technology, Private Bag X680, Pretoria 0001 (South Africa); Räisänen, J. [Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 University of Helsinki (Finland); Sajavaara, T. [Department of Physics, University of Jyväskylä, Survontie 9, 40014 Jyväskylä (Finland); Simon, A. [International Atomic Energy Agency, Division of Physical and Chemical Sciences, Vienna International Centre, P.O. Box 100, A-1400 Vienna (Austria); Institute of Nuclear Research of the Hungarian Academy of Sciences, (ATOMKI), P.O. Box 51, H-4001 Debrecen (Hungary)

    2015-10-01

    Silicon nitride is a technologically important material in a range of applications due to a combination of important properties. Ion beam analysis techniques, and in particular, heavy ion elastic recoil detection analysis can be used to determine the stoichiometry of silicon nitride films, which often deviates from the ideal Si{sub 3}N{sub 4}, as well as the content of impurities such as hydrogen, even in the presence of other materials or in a matrix containing heavier elements. Accurate quantification of IBA results depends on the basic data used in the data analysis. Quantitative depth profiling relies on the knowledge of the stopping power cross sections of the materials studied for the ions involved, which in the case of HI-ERDA is both the primary beam, and the recoiled species. We measured the stopping cross section of {sup 12}C, {sup 16}O, {sup 28}Si, {sup 35}Cl, {sup 58}Ni, {sup 79}Br, and {sup 127}I in a well-characterised silicon nitride membrane. The measurements were made by independent groups utilising different experimental setups and methods. In some cases there is extensive overlap of the energy range in different experiments, allowing a comparison of the different results. The four independent data sets reported in this work are in excellent agreement with each other, in the cases where similar energy ranges were measured. On the other hand, the data are in most cases higher than calculations made with the interpolative schemes SRIM and MSTAR together with the Bragg rule. Better agreement is found with MSTAR in some of the cases studied. This work is a significant extension of the heavy ion stopping power data base for silicon nitride.

  1. State-to-state dynamics of H+HX collisions. II. The H+HX→HX/sup dagger/+H (X = Cl,Br,I) reactive exchange and inelastic collisions at 1.6 eV collision energy

    International Nuclear Information System (INIS)

    Aker, P.M.; Germann, G.J.; Tabor, K.D.; Valentini, J.J.

    1989-01-01

    We report measurement of product state distributions for the rotationally and/or vibrationally excited HX formed in collisions of translationally hot H atoms with HX (X = Cl, Br, and I) at 1.6 eV collision energy. The product state distributions are probed after only one collision of the fast H atom, using coherent anti-Stokes Raman scattering spectroscopy. Whether proceeding by inelastic collisions or reactive exchange, the transfer of translational energy to vibrational and rotational energy is quite inefficient in H+HX collisions at 1.6 eV. For all three hydrogen halides only 2--3% of the initial translational energy appears as HX vibration. For H+HCl only 6% of the initial energy is converted to HCl rotational energy, while for H+HBr and H+HI, this percentage is twice as large, 11--12%, but still small. The indistinguishability of the two H atoms involved makes it impossible to distinguish reactive exchange from inelastic energy transfer in these H+HX collisions. However, the difference in rotational energy partitioning for H+HBr and H+HI as compared with H+HCl, suggests that reactive exchange is dominant in the former and inelastic energy transfer dominates in the latter. The total cross sections for the combined energy transfer/reactive exchange do not change much with the identity of X, being 13 +- 3, 11 +- 2, and 11 +- 2 A 2 , for H+HCl, H+HBr, and H+HI, respectively

  2. Nature of the bonding in the AuNgX (Ng = Ar, Kr, Xe; X = F, Cl, Br, I) molecules. Topological study on electron density and the electron localization function (ELF).

    Science.gov (United States)

    Makarewicz, Emilia; Gordon, Agnieszka J; Berski, Slawomir

    2015-03-19

    Topological analysis of the electron localization function (ELF) has been carried out for the AuNgX (Ng = Ar, Kr, Xe; X = F, Cl, Br, I) molecules using the wave function approximated by the CCSD, MP2, and DFT(B3LYP, M062X) methods including zero-order regular approximation (ZORA). In the Ng-F bond, the bonding disynaptic attractor V(Ng,F) is missing; therefore, there are no signs of the covalent binding. The nature of the Au-Ng bond depends on the computational method used. Analysis of the ELF carried out for the AuArF and AuXeF molecules, with the wave function approximated by the CCSD and MP2 methods, shows the V(Au,Ng) attractor possibly corresponding to a partially covalent binding between the gold and noble gas atom. However, its very small basin population (<1e) and a very large value of the variance of the basin population suggest that the Au-Ng bond has a very delocalized character. Such bond nature may be related to the charge shift concept with a resonance of the Au(-+)NgX, Au(+-)NgX hybrids. The weakest Au-Ng bond, in terms of the smallest amount of electron density for the V(Au,Ng) basin, is found for the AuKrF molecule with the CCSD method (0.13e). The MP2 method, however, does not yield any V(Au, Ng) population; hence, the covalent Au-Kr bond is not confirmed. Because the V(Au,Ng) attractor is also not observed with the DFT method, the proper characterization of the Au-Ng bond requires proper description of correlation effects. Additional studies on the Au2 and [AuXe](+) molecules, performed at the CCSD and B3LYP levels, exhibit no V(Au,Au) and V(Au,Xe) bonding basins either.

  3. A Theoretical Study of the Oxidation of Hg0 to HgBr2 in the Troposphere

    DEFF Research Database (Denmark)

    Goodsite, M. E.; Plane, J. M C; Skov, H.

    2004-01-01

    The oxidation of elemental mercury (Hg0) to the divalent gaseous mercury dibromide (HgBr2) has been proposed to account for the removal of Hg0 during depletion events in the springtime Arctic. The mechanism of this process is explored in this paper by theoretical calculations of the relevant rate...... coefficients. Rice-Ramsberger-Kassel-Marcus (RRKM) theory, together with ab initio quantum calculations where required, are used to estimate the following: recombination rate coefficients of Hg with Br, I, and O; the thermal dissociation rate coefficient of HgBr; and the recombination rate coefficients of Hg......Br with Br, I, OH, and O2. A mechanism based on the initial recombination of Hg with Br, followed by the addition of a second radical (Br, I, or OH) in competition with thermal dissociation of HgBr, is able to account for the observed rate of Hg 0 removal, both in Arctic depletion events and at lower...

  4. Preparation and characterization of (R,S)-[76Br]BrQNB: an analogue of QNB for PET

    International Nuclear Information System (INIS)

    Strijckmans, V.; Loc'h, C.; Ottaviani, M.; Maziere, B.; Lee, K.S.; Zeeberg, B.R.

    1997-01-01

    (R,S)-[ 76 Br]BrQNB was prepared for imaging mAChR by PET . (R,S)QNB was labelled with bromine-76 by electrophilic substitution of the tributylstannyl precursor using peracetic acid as oxidizing agent. The exchange between bromine-76 and the leaving group occurred in 20 min at room temperature. A chemically and radiochemically pure product was obtained with a final radiolabelling yield of 30%. Preliminary evaluation of pharmacological properties was performed in rats. In brain, biodistribution and autoradiography studies showed that the preferential localization of (R,S)-[ 76 Br]BrQNB was m-AChR rich structures. 6 h p.i. the radioactivity uptake in the posterior cortex was 1% ID/g and the striatum to cerebellum radioactivity ratio was 13.5. Metabolite study revealed that the radiotracer remains unchanged in brain for at least 3 h. (Author)

  5. Z-(-,-)-[76Br]BrQNP: a high affinity PET radiotracer for central and cardiac muscarinic receptors

    International Nuclear Information System (INIS)

    Strijckmans, V.; Coulon, C.; Loc'h, C.; Maziere, B.; Luo, H.; McPherson, D.W.; Knapp, F.F.

    1996-01-01

    Racemic E-1-azabicyclo[2.2.2]oct-3-yl α-(1-bromo-1-1-propen-3-yl)-α -hydroxy-α-phenylacetate (BrQNP) was prepared and evaluated in vivo as a potential candidate for imaging muscarinic acetylcholinergic receptors by Positron Emission Tomography. Initial in vivo blocking studies utilizing Z-(-,-)-[ 125 I]IQNP as a radiolabelled muscarinic probe demonstrated that a preinjection of cold E-BrQNP effectively blocks the uptake of the radiolabelled probe in the brain and heart, by 71% and 86% respectively. Z-(-,-)-[ 76 Br]BrQNP was prepared by electrophilic substitution from a tributylstannyl precursor. Peracetic acid and chloramine T was evaluated as oxidizing agents. After purification by SPE and RP-HPLC, radiolabelling yields of 85% and 95% were obtained with peracetic acid and chloramine T, respectively. The final radiochemical yield was 70% for both oxidizing agents. (author)

  6. BR2 mixed core management

    International Nuclear Information System (INIS)

    Ponsard, B.; Beeckmans, A.

    1997-01-01

    The BR2 fuel cycle management can be optimized by the fabrication and the irradiation of fuel elements with uranium recovered from the reprocessing of BR2 spent fuel. The VIn E fuel performances could be upgraded by increasing the amount of burnable poisons, the fuel mass, the fuel density, ... in order to obtain a higher reactivity effect at a burnup of about β=12% and a longer cycle duration. The preliminary results of the calculations need however to be confirmed by measurements on effective reactor loads. (author)

  7. Thermodynamic assessment of NdBr3 unary and LiBr-NdBr3 binary system

    International Nuclear Information System (INIS)

    Gong Weiping; Gaune-Escard, Marcelle

    2006-01-01

    Phase diagram and thermodynamic properties calculations were carried out on the NdBr 3 unary and the LiBr-NdBr 3 binary systems over the entire temperature and composition range, respectively. The Gibbs energy of NdBr 3 was evaluated using an independent polynomial to fit the experimental thermodynamic properties. The liquid phase in the LiBr-NdBr 3 system was described by the two sub-lattice ionic solution model (Li + ) P : (Br - , NdBr 6 -3 , NdBr 3 ) Q . Comparisons between the calculated phase diagram and thermodynamic quantities show that all reliable experimental information was satisfactorily accounted for by the present thermodynamic description

  8. Experimental study of the transport of HTO, {sup 3}6Cl and {sup 1}37Cs through barriers of bentonite and granite; Estudio experimental del transporte de HTO, {sup 3}6Cl y {sup 1}37Cs a traves de barreras de bentonita y granito

    Energy Technology Data Exchange (ETDEWEB)

    Mingarro, M.; Garcia-Gutierrez, M.; Morejon, J.; Missana, T.; Gil, P.

    2013-07-01

    The evaluation of the behavior of the engineered (bentonite) and natural (granite) barrier of a deep geological repository of high level radioactive waste, needs the knowledge of radionuclide migration and retention processes under conditions as similar as possible to the real ones. In CIEMAT a large-scale experiment has been designed with the objective of studying diffusive transport at the bentonite/granite interface of a geological repository in crystalline rock. The diffusion of three tracers has been analyzed: HTO (as conservative and neural element); Cl (as conservative anionic element) and Cs (as conservative cationic element). It was observed that cesium disappeared very fast from the water deposit, due to its strong retention on bentonite. On the other hand, HTO and Cl, disappeared much slower and could be finally detected in the granite at several centimeters from the original source.

  9. Present status of TCA/BR Tokamak

    International Nuclear Information System (INIS)

    Nascimento, I.C.; Galvao, R.M.O.; Tuszel, A.G.

    1997-01-01

    The TCA tokamak is being partially reconstructed and reassembled in the Plasma Laboratory of The University of Sao Paulo, and afterwards it will be named TCA/BR. The first discharges are expected by June/July of next year. The main scientific objectives envisaged for the machine are: Alfven wave heating and current drive, confinement improvement, disruptions and turbulence. In this paper we also describe: (i) the present status of the project; (ii) the diagnostic system; (iii) the control and data acquisition system; (iv) the RF system for the excitation of Alfven waves, that are being developed, and also the results of predictive transport simulations of its performance. (author)

  10. NQR and X-ray crystal structure studies of cadmium halide complexes: [C(NH{sub 2}){sub 3}]CdI{sub 3} and [4-ClC{sub 6}H{sub 5}NH{sub 3}]{sub 3}CdBr{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Gesing, Thorsten M.; Lork, Enno [Bremen Univ. (Germany). MAPEX Center for Material and Processes; Terao, Hiromitsu [Tokushima Univ. (Japan). Faculty of Integrated Arts and Sciences; Ishihara, Hideta [Saga Univ. (Japan). Faculty of Culture and Education

    2016-05-01

    The crystal structures of [C(NH{sub 2}){sub 3}]CdI{sub 3} (1) and [4-ClC{sub 6}H{sub 5}NH{sub 3}]{sub 3}CdBr{sub 5} (2) have been determined at 100 K: monoclinic, Cc, a = 828.75(3) pm, b = 1615.31(5) pm, c = 810.64(3) pm, and β = 106.5820(10) for 1; monoclinic, P2{sub 1}/c, a = 1486.93(5) pm, b = 794.31(3) pm, c = 2290.59(7) pm, and β = 99.6830(10) for 2. The structure of 1 has an infinite chain of anions consisting of [CdI{sub 4}] tetrahedra sharing two corners. The structure of 2 has an infinite chain of anions consisting of [CdBr{sub 6}] octahedra sharing two corners in cis positions. In both structures, isolated cations are connected to the anion chains through weak hydrogen bonds Cd-X..H to result in three-dimensional network structures. In accordance with the crystal structures, three {sup 127}I (m = ±1/2 <-> m = ±3/2), five {sup 81}Br, and three {sup 35}Cl nuclear quadrupole resonance (NQR) lines were observed for 1 and 2. The NQR spectra reflect the anion chain structures and their weak hydrogen bonds. The MO calculations of the models [Cd{sub 5}I{sub 16}]{sup 6-} for 1 and [Cd{sub 3}Br{sub 16}]{sup 10-} for 2 estimate only about half the values for the NQR frequencies but give accurate electric field gradient directions.

  11. Molecular structures and thermodynamic properties of 12 gaseous cesium-containing species of nuclear safety interest: Cs 2, CsH, CsO, Cs 2O, CsX, and Cs 2X 2 (X = OH, Cl, Br, and I)

    Science.gov (United States)

    Badawi, Michael; Xerri, Bertrand; Canneaux, Sébastien; Cantrel, Laurent; Louis, Florent

    2012-01-01

    Ab initio electronic structure calculations at the coupled cluster level with a correction for the triples extrapolated to the complete basis set limit have been made for the estimation of the thermochemical properties of Cs 2, CsH, CsO, Cs 2O, CsX, and Cs 2X 2 (X = OH, Cl, Br, and I). The standard enthalpies of formation and standard molar entropies at 298 K, and the temperature dependence of the heat capacities at constant pressure were evaluated. The calculated thermochemical properties are in good agreement with their literature counterparts. For Cs 2, CsH, CsOH, Cs 2(OH) 2, CsCl, Cs 2Cl 2, CsBr, CsI, and Cs 2I 2, the calculated ΔfH298K∘ values are within chemical accuracy of the most recent experimental values. Based on the excellent agreement observed between our calculated ΔfH298K∘ values and their literature counterparts, the standard enthalpies of formation at 298 K are estimated to be the following: ΔfH298K∘ (CsO) = 17.0 kJ mol -1 and ΔfH298K∘ (Cs 2Br 2) = -575.4 kJ mol -1.

  12. Refurbishment programme for the BR2-reactor

    Energy Technology Data Exchange (ETDEWEB)

    Koonen, E [Centre d' Etude de l' Energie Nucleaire, Studiecentrum voor Kernenergie, BR2 Department, Boeretang, Mol (Belgium)

    1992-07-01

    BR2 is a high flux engineering test reactor, which differs from comparable material testing reactors by its specific core array (fig. 1). It is a heterogeneous, thermal, tank-in-pool type reactor, moderated by beryllium and light water, which serves also as coolant. The fuel elements consist of cylindrical assemblies loaded in channels materialized by hexagonal beryllium prisms. The central 200 mm channel is vertical, while all others are inclined and form a hyperbolical arrangement around the central one. This feature combines a very compact core with the requirement of sufficient space for individual access to all channels through penetrations in the top cover of the aluminium pressure vessel. Each channel may hold a fuel element, a control rod, an experiment, an irradiation device or a beryllium plug. The refurbishment Program According to the present programme of C.E.N./S.C.K., BR2 will be in operation until 1996. At that time, the beryllium matrix will reach its foreseen end-of-life. In order to continue operation beyond this point, a thorough refurbishment of the reactor is foreseen, in addition to the unavoidable replacement of the matrix, to ensure quality of the installation and compliance with modern standards. Some fundamental options have been taken as a starting point: BR2 will continue to be used as a classical MTR, i.e. fuel and material irradiations and safety experiments with some additional service-activities. The present configuration is optimized for that use and there is no specific experimental requirement to change the basic concepts and performance characteristics. From the customers viewpoint, it is desirable to go ahead with the well-known features of BR2, to maintain a high degree of availability and reliability and to minimize the duration of the long shutdown. It is also important to limit the amount of nuclear liabilities. So the objective of the refurbishment programme is the life extension of BR2 for about 15 years, corresponding to

  13. Refurbishment programme for the BR2-reactor

    International Nuclear Information System (INIS)

    Koonen, E.

    1992-01-01

    BR2 is a high flux engineering test reactor, which differs from comparable material testing reactors by its specific core array (fig. 1). It is a heterogeneous, thermal, tank-in-pool type reactor, moderated by beryllium and light water, which serves also as coolant. The fuel elements consist of cylindrical assemblies loaded in channels materialized by hexagonal beryllium prisms. The central 200 mm channel is vertical, while all others are inclined and form a hyperbolical arrangement around the central one. This feature combines a very compact core with the requirement of sufficient space for individual access to all channels through penetrations in the top cover of the aluminium pressure vessel. Each channel may hold a fuel element, a control rod, an experiment, an irradiation device or a beryllium plug. The refurbishment Program According to the present programme of C.E.N./S.C.K., BR2 will be in operation until 1996. At that time, the beryllium matrix will reach its foreseen end-of-life. In order to continue operation beyond this point, a thorough refurbishment of the reactor is foreseen, in addition to the unavoidable replacement of the matrix, to ensure quality of the installation and compliance with modern standards. Some fundamental options have been taken as a starting point: BR2 will continue to be used as a classical MTR, i.e. fuel and material irradiations and safety experiments with some additional service-activities. The present configuration is optimized for that use and there is no specific experimental requirement to change the basic concepts and performance characteristics. From the customers viewpoint, it is desirable to go ahead with the well-known features of BR2, to maintain a high degree of availability and reliability and to minimize the duration of the long shutdown. It is also important to limit the amount of nuclear liabilities. So the objective of the refurbishment programme is the life extension of BR2 for about 15 years, corresponding to

  14. Crystal structures of hydrates of simple inorganic salts. III. Water-rich aluminium halide hydrates: AlCl3 · 15H2O, AlBr3 · 15H2O, AlI3 · 15H2O, AlI3 · 17H2O and AlBr3 · 9H2O.

    Science.gov (United States)

    Schmidt, Horst; Hennings, Erik; Voigt, Wolfgang

    2014-09-01

    Water-rich aluminium halide hydrate structures are not known in the literature. The highest known water content per Al atom is nine for the perchlorate and fluoride. The nonahydrate of aluminium bromide, stable pentadecahydrates of aluminium chloride, bromide and iodide, and a metastable heptadecahydrate of the iodide have now been crystallized from low-temperature solutions. The structures of these hydrates were determined and are discussed in terms of the development of cation hydration spheres. The pentadecahydrate of the chloride and bromide are isostructural. In AlI(3) · 15H2O, half of the Al(3+) cations are surrounded by two complete hydration spheres, with six H2O in the primary and 12 in the secondary. For the heptadecahydrate of aluminium iodide, this hydration was found for every Al(3+).

  15. Operating Experience with the BR-5 Reactor; Experience acquise aupres du reacteur BR-5; Opyt ehkspluatatsii reaktora BR-5; Experiencia practica con el reactor BR-5

    Energy Technology Data Exchange (ETDEWEB)

    Lejpunskij, A. I.; Kazachkovskij, O. D.; Pinkhasik, M. S.; Aristarkhov, N. N.; Karpov, A. V.; Larin, E. P.; Efimov, I. A.

    1963-10-15

    remontnykh rabot na radioaktivnom zhidkometallicheskom konture reaktora na bystrykh nejtronakh BR-5. Osveshchayutsya voprosy ehkspluatatsii reaktora posle dostizheniya proektnogo 2%-nogo vygoraniya topliva pri nalichii nekotorogo narusheniya plotnosti otdel'nykh teplovydelyaptsikh ehlementov. Provoditsya opyt po razgruzke aktivnoj zony, issledovaniyu sostoyaniya i germetichnosti teplovydelyaptsikh ehlementov, dezaktivatsii oborudovaniya i truboprovodov I radioaktivnogo kontura posle dostizheniya 5% vygoraniya topliva. (author)

  16. Ge14 Br8 (PEt3 )4 : A Subhalide Cluster of Germanium.

    Science.gov (United States)

    Kunz, Tanja; Schrenk, Claudio; Schnepf, Andreas

    2018-04-03

    Heating a metastable solution of Ge I Br to room temperature led to the first structurally characterized metalloid subhalide cluster Ge 14 Br 8 (PEt 3 ) 4 (1). Furthermore 1 can be seen as the first isolated binary halide cluster on the way from Ge I Br to elemental germanium, giving insight into the complex reaction mechanism of its disproportionation reaction. Quantum chemical calculations further indicate that a classical bonding situation is realized within 1 and that the last step of the formation of 1 might include the trapping of GeBr 2 units. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Chanel-brändin nuorentaminen Suomessa

    OpenAIRE

    Auvinen, Elina

    2017-01-01

    Tämän opinnäytetyön tavoitteena oli kartoittaa Chanel-kosmetiikkabrändin imagoa ja asiakaskuntaa Suomessa sekä luoda saatujen tulosten pohjalta kehitysehdotuksia Chanel-brändin markkinointiin Suomessa brändin nuorentamisen näkökulmasta. Työn toimeksiantaja oli Chanel-brändin jakelija Oy Transmeri Ab. Teoriataustassa käsiteltiin laajasti erilaisia brändin nuorentamiseen liittyviä aihepiirejä; bränditeoriaa, brändien uudistamista, luksusbrändien erityispiirteitä sekä niiden asiakkaita, digitaal...

  18. Studies on the phase diagram of LiBr-SrBr2 system

    International Nuclear Information System (INIS)

    Mahendran, K.H.; Sujatha, K.; Sridharan, R.; Gnanasekaran, T.

    2003-01-01

    Binary LiBr-SrBr 2 system was investigated using differential scanning calorimetry (DSC) and the equilibrium phases at different compositions were identified using X-ray diffraction (XRD). This system has a compound LiSr 2 Br 5 , and exhibits a eutectic reaction between this compound and LiBr at 434 deg. C and the eutectic has a composition of 35 mol% SrBr 2 . The compound LiSr 2 Br 5 undergoes peritectic decomposition at 484 deg. C. From the DSC and XRD results, phase diagram of the LiBr-SrBr 2 system is constructed

  19. The dynamics of the Hg + Br2 reaction: elucidation of the reaction mechanism for the Br exchange reaction.

    Science.gov (United States)

    Jambrina, P G; Menéndez, M; Aoiz, F J

    2017-06-28

    In spite of its importance in the Hg atmospheric chemistry, the dynamics of the Hg + Br 2 → HgBr + Br reaction is poorly understood. In this article, we have carried out a comprehensive study of the reaction mechanism of this reaction by means of quasiclassical trajectories (QCTs) on an existing ab initio potential energy surface (PES). The reaction has a non trivial dynamics, as a consequence of its large endothermicity, the presence of a deep potential well, and the competition between the Br exchange and the collision induced dissociation processes. Our calculations demonstrate that insertion is only relevant at energies just above the reaction threshold and that, at energies above 2.3 eV, HgBr formation typically takes place via a sort of frustrated dissociation. In order to compare directly with the results obtained in extensive cross molecular beam experiments for the homologous reaction with I 2 , angular distributions in the laboratory frame for Hg + Br 2 have been simulated under similar experimental conditions. The lack of agreement at the highest energies considered suggests that either the two reactions have substantially different mechanisms or that calculations on a single PES cannot account for the dynamics at those energies.

  20. The Higgs Boson in the $H\\to ZZ^{(*)}\\to4l$ decay channel with the ATLAS detector at the LHC

    CERN Document Server

    Salvucci, Antonio; Filthaut, Frank

    This thesis is aiming to present the work contributed by the author in the context of the ATLAS experiment and the search for the Standard Model Higgs boson in the $H\\to ZZ^{(∗)}\\to 4l$ decay channel using the proton-proton collision data collected during 2011 and 2012. This decay channel is one of the main channels where the discovery of the Higgs boson has been made. It provides a very clean final state signature and the possibility to fully reconstruct the Higgs mass with excellent detector resolution. Moreover, it is the most suitable instrument to study the spin and parity state of the Higgs boson, since one can reconstruct the full decay chain and derive the intrinsic properties of the $H\\to ZZ$ decay amplitude from angular and invariant mass distribution of the final state. This thesis is organized as follow. An introduction of the theoretical aspects of the Standard Model and the spontaneous symmetry breaking are presented. The LHC and the ATLAS detector are introduced. For the search for the Higgs ...

  1. Stig Brøgger's Artists' Books

    DEFF Research Database (Denmark)

    Ørum, Tania; Hvis Kromann, Thomas

    Introduction and presentation of the many artist's books made by the Danish artist Stig Brøgger......Introduction and presentation of the many artist's books made by the Danish artist Stig Brøgger...

  2. Contributions of BrCl, Br2, BrOCl, Br2O, and HOBr to regiospecific bromination rates of anisole and bromoanisoles in aqueous solution.

    Science.gov (United States)

    Sivey, John D; Bickley, Mark A; Victor, Daniel A

    2015-04-21

    When bromide-containing waters are chlorinated, conventional wisdom typically assumes HOBr is the only active brominating agent. Several additional and often-overlooked brominating agents (including BrCl, Br2, BrOCl, Br2O) can form in chlorinated waters, albeit at generally lower concentrations than HOBr. The extent to which these additional brominating agents influence bromination rates of disinfection byproduct precursors is, however, poorly understood. Herein, the influence of BrCl, Br2, BrOCl, Br2O, and HOBr toward rates of sequential bromination of anisole was quantified. Conditions affecting bromine speciation (e.g., pH, concentrations of chloride, bromide, and chlorine) were varied, and regiospecific second-order rate constants were calculated for reactions of each brominating agent with anisole, 2-bromoanisole, and 4-bromoanisole. The regioselectivity of anisole bromination changed with pH, consistent with the participation of more than one brominating agent. Under conditions representative of chlorinated drinking water, contributions to bromination rates decreased as BrCl > BrOCl > HOBr > Br2O (Br2 negligible). The second-order rate constant determined for net bromination of anisole by HOBr is up to 3000-times less than reported in previous studies (which assumed HOBr was the only active brominating agent). Accordingly, models that assume HOBr is the only kinetically relevant brominating agent in solutions of free bromine may be insufficient for reactions involving modestly nucleophilic organic compounds.

  3. Core electron binding energy shifts of AlBr3 and Al2Br6 vapor

    International Nuclear Information System (INIS)

    Mueller, Astrid M.; Plenge, Juergen; Leone, Stephen R.; Canton, Sophie E.; Rude, Bruce S.; Bozek, John D.

    2006-01-01

    The Al 2p and Br 3d inner-shell photoelectron spectra of aluminum tribromide monomer and dimer vapor were measured at 90 and 95 eV photon energy, respectively, to determine the core electron binding energies of the atoms in the two molecular species. While AlBr 3 has three identical Br atoms, Al 2 Br 6 exhibits four terminal and two bridging Br atoms. The species are identified by their distinct valence photoelectron spectra. Comparison of the observed Al 2p 1/2 and Al 2p 3/2 electron binding energies of AlBr 3 with those of Al 2 Br 6 shows that there is a chemical shift of (0.15 ± 0.03) eV to lower energy in the dimer. In Al 2 Br 6 , an assignment is proposed in which the Br 3d 3/2 and Br 3d 5/2 binding energies of terminal Br atoms are (1.18 ± 0.03) eV lower than those of bridging Br atoms. This assignment assumes that both types of Br atoms have similar cross-sections for ionization. With this result, the Br 3d 3/2 and Br 3d 5/2 binding energies of Br atoms in AlBr 3 are (0.81 ± 0.03) eV lower than those of bridging Br atoms of the dimer but (0.37 ± 0.03) eV higher than those of terminal Br atoms of the dimer. The obtained chemical shifts are considered in terms of the binding relations and electron density distributions in both molecules. Chemical shifts that are larger than a few hundred millielectron volts, as observed in the Al 2 Br 6 /AlBr 3 system, offer potential to study the dissociation dynamics of the dimer in a femtosecond visible or ultraviolet-pump/XUV-probe experiment

  4. Photodissociation of C3H5Br and C4H7Br at 234 nm

    International Nuclear Information System (INIS)

    Kim, Hyun Kook; Paul, Dababrata; Hong, Ki Ryong; Cho, Ha Na; Kim, Tae Kyu; Lee, Kyoung Seok

    2012-01-01

    The photodissociation dynamics of cyclopropyl bromide (C-3H 5 Br) and cyclobutyl bromide (C 4 H 7 Br) at 234 nm was investigated. A two-dimensional photofragment ion-imaging technique coupled with a [2+1] resonance enhanced multiphoton ionization scheme was utilized to obtain speed and angular distributions of the nascent Br( 2 P 3/2 ) and Br*( 2 P 1/2 ) atoms. The recoil anisotropies for the Br and Br* channels were measured to be βBr = 0.92 ± 0.03 and βBr* = 1.52 ± 0.04 for C 3 H 5 Br and βBr = 1.10 ± 0.03 and βBr* = 1.49 ± 0.05 for C 4 H 7 Br. The relative quantum yield for Br was found to be ΦBr = 0.13 ± 0.03 and for C 3 H 5 Br and C 4 H 7 Br, respectively. The soft radical limit of the impulsive model adequately modeled the related energy partitioning. The nonadiabatic transition probability from the 3A' and 4A' potential energy surfaces was estimated and discussed

  5. Firmad kujundavad Eesti brändi / Evelin Ojamets

    Index Scriptorium Estoniae

    Ojamets, Evelin

    2001-01-01

    Eesti mainekujundamise projektijuhi Evelin Int-Lamboti sõnul tuleb Eesti märgiks valida tooted, mis tarbija jaoks ei ole juba seotud mõne teise riigi imagoga. ES Turu-uuringute AS-i koduleheküljel toimunud online-turundusfoorumist. Eesti brändid

  6. Brændeovne duer IKKE til opvarmning

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    2007-01-01

    Miljøstyrelsens og den samlede regerings ambitioner med brændeovnene kritiseres som uansvarlige p.g.a. den allerede længe formodede, men i dag velanalyserede og for Danmark som helhed beskrevne  alvorlige luftforurening især med klorerede dioxiner, PAH og fine partikler. Figenbladet med den såkal...

  7. Br2 induced oxidative pore modification of a porous coordination network.

    Science.gov (United States)

    Ohtsu, Hiroyoshi; Kawano, Masaki

    2016-01-14

    Iodinated pores of a Zn-based coordination network were modified by Br2 oxidation to produce brominated pores in a polycrystalline-to-polycrystalline manner while maintaining the same network topology. Ab initio X-ray powder diffraction analysis and Raman spectroscopy revealed that the brominated pore can trap Br2 or I2 by strong σ/π-type interactions. A kinetic study in solution revealed that the pore modification by Br2 oxidation is much faster than the Br2 encapsulation process.

  8. Yrityksen brändin uudistaminen

    OpenAIRE

    Saarimaa, Petri

    2015-01-01

    Brändin rakentaminen on tänä päivänä tärkeä osa yrityksen näkyvyyden ja kilpailukyvyn edistämisessä. Huolellisesti rakennetulla brändillä ja hyvällä markkinoinnilla yritys voi erottua kilpailijoistaan positiivisesti. Tie menestyvään brändiin on kuitenkin pitkä prosessi. Toimeksiantajana opinnäytetyössä toimi rakennusyritys Rakennus Vuoriot Oy. Opinnäytetyön tavoitteena oli toteuttaa yritykselle brändin uudistaminen luomalla kokonaan uusi perusta ja rakennusosat olemassa olevalle brändille...

  9. The long periodicity phase (LPP) controversy part I: The influence of a natural-like ratio of the CER[EOS] analogue [EOS]-br in a CER[NP]/[AP] based stratum corneum modelling system: A neutron diffraction study.

    Science.gov (United States)

    Schmitt, Thomas; Lange, Stefan; Sonnenberger, Stefan; Dobner, Bodo; Demé, Bruno; Langner, Andreas; Neubert, Reinhard H H

    2018-06-18

    This study used neutron diffraction to investigate a ceramide-[NP] C24/[AP] C24 /[EOS]-br C30/cholesterol/lignoceric acid (0.6: 0.3: 0.1: 0.7: 1) based stratum corneum modelling system. By adding specifically deuterated ceramides-[NP]-D 3 , [AP]-D 3 , and [EOS]-br-D 3 , detailed information on the lamellar and the nanostructure of the system was obtained. For the short periodicity phase a natural-like lamellar repeat distance of 5.47 ± 0.02 nm was observed, similar to the [NP]/[AP] base system without the [EOS]-br. Unlike in this system the ceramides here were slightly tilted, hinting towards a slightly less natural arrangement. Due to the deuteration it was possible to observe that the long ceramide chains were overlapping in the lamellar mid-plane. This is considered to be an important feature for the natural stratum corneum. Despite the presence of a ceramide [EOS] analogue - able to form a long phase arrangement - no distinct long periodicity phase was formed, despite a slightly higher than natural ω-acyl ceramide ratio of 10 mol%. The deuterated variant of this ceramide determined that the very long ceramide was integrated into the short periodicity phase, spanning multiple layers instead. The - compared to the base system - unchanged repeat distance highlights the stability of this structure. Furthermore, the localisation of the very long ceramide in the short periodicity phase indicates the possibility of a crosslinking effect and thus a multilayer stabilizing role for the ceramide [EOS]. It can be concluded, that additionally to the mere presence of ceramide-[EOS] more complex conditions have to be met in order to form this long phase. This has to be further investigated in the future. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Global observations of tropospheric BrO columns using GOME-2 satellite data

    Directory of Open Access Journals (Sweden)

    N. Theys

    2011-02-01

    Full Text Available Measurements from the GOME-2 satellite instrument have been analyzed for tropospheric BrO using a residual technique that combines measured BrO columns and estimates of the stratospheric BrO content from a climatological approach driven by O3 and NO2 observations. Comparisons between the GOME-2 results and BrO vertical columns derived from correlative ground-based and SCIAMACHY nadir observations, present a good level of consistency. We show that the adopted technique enables separation of stratospheric and tropospheric fractions of the measured total BrO columns and allows quantitative study of the BrO plumes in polar regions. While some satellite observed plumes of enhanced BrO can be explained by stratospheric descending air, we show that most BrO hotspots are of tropospheric origin, although they are often associated to regions with low tropopause heights as well. Elaborating on simulations using the <i>p>-TOMCAT tropospheric chemical transport model, this result is found to be consistent with the mechanism of bromine release through sea salt aerosols production during blowing snow events. No definitive conclusion can be drawn however on the importance of blowing snow sources in comparison to other bromine release mechanisms. Outside polar regions, evidence is provided for a global tropospheric BrO background with column of 1–3 × 1013 molec cm−2, consistent with previous estimates.

  11. BR2 reactor neutron beams

    International Nuclear Information System (INIS)

    Neve de Mevergnies, M.

    1977-01-01

    The use of reactor neutron beams is becoming increasingly more widespread for the study of some properties of condensed matter. It is mainly due to the unique properties of the ''thermal'' neutrons as regards wavelength, energy, magnetic moment and overall favorable ratio of scattering to absorption cross-sections. Besides these fundamental reasons, the impetus for using neutrons is also due to the existence of powerful research reactors (such as BR2) built mainly for nuclear engineering programs, but where a number of intense neutron beams are available at marginal cost. A brief introduction to the production of suitable neutron beams from a reactor is given. (author)

  12. 73Ge, 119Sn and 207Pb: general cooperative effects of single atom ligands on the NMR signals observed in tetrahedral [MXnY4-n] (M = Ge, Sn, Pb; 1 ≤ n ≤ 4; X, Y = Cl, Br, I) coordination compounds of heavier XIV group elements.

    Science.gov (United States)

    Benedetti, M; De Castro, F; Fanizzi, F P

    2017-02-28

    An inverse linear relationship between 73 Ge, 119 Sn and 207 Pb NMR chemical shifts and the overall sum of ionic radii of coordinated halido ligands has been discovered in tetrahedral [MX n Y 4-n ] (M = Ge, Sn, Pb; 1 ≤ n ≤ 4; X, Y = Cl, Br, I) coordination compounds. This finding is consistent with a previously reported correlation found in octahedral, pentacoordinate and square planar platinum complexes. The effect of the coordinated halido ligands acting on the metal as shielding conducting rings is therefore confirmed also by 73 Ge, 119 Sn and 207 Pb NMR spectroscopy.

  13. Copper(I), silver(I) and gold(I) halide complexes with the dithioformamidinium dihalides

    Science.gov (United States)

    Peyronel, Giorgio; Malavasi, Wanda; Pignedoli, Anna

    Some copper(I), silver(I) and gold(I) halide complexes with the dithioformamidinium dihalides (Tu 2X 2) were prepared and studied by infrared spectroscopy and conductometry: 3CuX.2Tu 2X 2(XCl,I), CuBr.Tu 2Br 2, 4CuBr.3.5Tu 2Br 2.MeOH, 2CuBr.Tu 2Br 2.0.66EtOH, 3CuI.2Tu 2I 2, 2AgCl.2.5Tu 2Cl 2, 3AgCl.2Tu 2Cl 2.0.5EtOH, 3AgCl.Tu 2Cl 2, 2AgBr.2Tu 2Br 2.0.5Tu 2(NO 3) 2.H 2O, AgBr.Tu 2Br 2, 4AgBr.Tu 2Br 2, 4AgI.0.5Tu 2I 2.EtOH, AuCl.1.5Tu 2Cl 2, 4AuCl.3.5Tu 2Cl 2.2DMF, AuBr.4Tu 2Br 2, AuBr.2Tu 2Br 2.1.5DMF, AuI.5Tu 2I 2, AuI.Tu 2I 2. A decrease of the ν(NH), δ(NH 2) and ν(CN 2) frequencies and an increase of the ν(CS) frequencies indicate an N-coordination of the dithioformamidinium cation to the metal ions; ν(MN) and ν(MX) frequencies are tentatively assigned in the far-infrared spectra.

  14. Formation of methane versus benzene in the reactions of (C{sub 5}Me{sub 5}){sub 2}Th(CH{sub 3}){sub 2} with [CH{sub 3}PPh{sub 3}]X (X=Cl, Br, I) yielding thorium-carbene or thorium-ylide complexes

    Energy Technology Data Exchange (ETDEWEB)

    Rungthanaphatsophon, Pokpong; Behrle, Andrew C.; Barnes, Charles L.; Walensky, Justin R. [Department of Chemistry, University of Missouri, Columbia, MO (United States); Bathelier, Adrien; Castro, Ludovic; Maron, Laurent [Toulouse Univ. and CNRS, INSA, UPS, CNRS, UMR, UMR 5215, LPCNO (France)

    2017-10-09

    The reaction of (C{sub 5}Me{sub 5}){sub 2}Th(CH{sub 3}){sub 2} with the phosphonium salts [CH{sub 3}PPh{sub 3}]X (X=Cl, Br, I) was investigated. When X=Br and I, two equivalents of methane are liberated to afford (C{sub 5}Me{sub 5}){sub 2}Th[CHPPh{sub 3}]X, rare terminal phosphorano-stabilized carbenes with thorium. These complexes feature the shortest thorium-carbon bonds (∼2.30 Aa) reported to date, and electronic structure calculations show some degree of multiple bonding. However, when X=Cl, only one equivalent of methane is lost with concomitant formation of benzene from an unstable phosphorus(V) intermediate, yielding (C{sub 5}Me{sub 5}){sub 2}Th[κ{sup 2}-(C,C{sup '})-(CH{sub 2})(CH{sub 2})PPh{sub 2}]Cl. Density functional theory (DFT) investigations of the reaction energy profiles for [CH{sub 3}PPh{sub 3}]X, X=Cl and I showed that in the case of iodide, thermodynamics prevents the production of benzene and favors formation of the carbene. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Surfactant-promoted reactions of Cl2 and Br2 with Br- in glycerol.

    Science.gov (United States)

    Faust, Jennifer A; Dempsey, Logan P; Nathanson, Gilbert M

    2013-10-17

    Gas-liquid scattering experiments are used to explore reactions of gaseous Cl2 and Br2 with a 0.03 M solution of the surfactant tetrahexylammonium bromide (THABr) dissolved in glycerol. At thermal collision energies, 79 ± 2% of incident Cl2 molecules react with Br(-) to form Cl2Br(-) in the interfacial region. This reaction probability is three times greater than the reactivity of Cl2 with 3 M NaBr-glycerol, even though the interfacial Br(-) concentrations are similar in each solution. We attribute the high 79% uptake to the presence of surface THA(+) ions that stabilize the Cl2Br(-) intermediate as it is formed in the charged, hydrophobic pocket created by the hexyl chains. Cl2Br(-) generates the single exchange product BrCl in a 1% yield close to the surface, while the remaining 99% desorbs as the double exchange product Br2 over >0.1 s after diffusing deeply into the bulk. When NaCl is added to the surfactant solution in a 20:1 Cl(-)/Br(-) ratio, the Cl2 reaction probability drops from 79% to 46 ± 1%, indicating that Cl(-) in the interfacial region only partially blocks reaction with Br(-). In parallel, we observe that gaseous Br2 molecules dissolve in 0.03 M THABr for 10(4) times longer than in 3 M NaBr. We attribute this change to formation of stabilizing interfacial and bulk-phase THA(+)Br3(-) ion pairs, in analogy with the capture of Cl2 and formation of THA(+)Cl2Br(-) pairs. The THA(+) ion appears to be a powerful interfacial catalyst for promoting reaction of Cl2 and Br2 with Br(-) and for ferrying the resultant ions into solution.

  16. brıs Türk Tiyatro Yazınının İlk Yılları ve Safa Yahut Netice-i İbtila The Primary Years Of Turkish Cypriot Play-Writing And “Safa Yahut Netice-i İbtila

    Directory of Open Access Journals (Sweden)

    Yurdal CİHANGİR

    2013-07-01

    Full Text Available The first signs of Cyprus Turkish Theatre Literature were encountered when Ottomans added Cyprus within their Empire boundaries. They sent settlers to the island who brought their own way of life, beliefs, culture and traditions together with them; thus forming a new society. „Karagoz‟, „Meddah‟ and „Ortaoyunu‟ were a part of thisculture and tradition. The Ottomans, having ruled Cyprus for 300years, rented the island to the British in 1878 and then completelyhanded over the island to them in 1914. Newspapers started to bepublished in this era, since 1980‟s. Like other literary types, firstexamples relating to theatre were also seen in the newspapers. In thefirst humour-based newspaper „Kokonoz‟ published by Ahmet TevfikEfedi, some of his own writings had theatrical characteristics. In thesecond humour-based newspaper by him, „Akbaba‟, there was apublication of an incomplete theatre production. L. Şişmanyan‟s workwhich only had three issues was entitled „Namus Intikami YahutDilenci‟. The first published theatre production, as it is known to-date,is Kaytazade Nazim‟s writings entitled “ Safa Yahut Netice-i Ibtila”. Thetheme of this production, which was published in 1909 in Nicosia atMirat-ı Zaman Printing House, relates to a love adventure in Istanbulduring „Mesrutiyet‟ years. The story revolves around Safa, a Pasha‟sson, who falls in love with their maid; how he stands against his family,and the bitter end of this love affair between Safa and his lover. Theproduction, being the first of its kind in Cyprus Turkish Literature andTheatre, therefore carries high significance. Kıbrıs Türk Tiyatro edebiyatının ilk izlerine, Osmanlı, kendi imparatorluk topraklarına kattıktan sonra Ada‟ya iskan için gönderdiği ve kendi yaşasyış biçimlerini, inanış, kültür ve geleneklerini de beraberlerinde taşımış olan insanların Ada‟da yeni bir toplum oluşturmaya çalıştıkları zamanla birlikte

  17. A comparative ab initio study of Br2*- and Br2 water clusters.

    Science.gov (United States)

    Pathak, A K; Mukherjee, T; Maity, D K

    2006-01-14

    The work presents ab initio results on structure and electronic properties of Br2*-.nH2O(n=1-10) and Br2.nH2O(n=1-8) hydrated clusters to study the effects of an excess electron on the microhydration of the halide dimer. A nonlocal density functional, namely, Becke's half-and-half hybrid exchange-correlation functional is found to perform well on the present systems with a split valence 6-31++G(d,p) basis function. Geometry optimizations for all the clusters are carried out with several initial guess structures and without imposing any symmetry restriction. Br2*-.nH2O clusters prefer to have symmetrical double hydrogen-bonding structures. Results on Br2.nH2O(n>or=2) cluster show that the O atom of one H2O is oriented towards one Br atom and the H atom of another H2O is directed to other Br atom making Br2 to exist as Br+-Br- entity in the cluster. The binding and solvation energies are calculated for the Br2*-.nH2O and Br2.nH2O clusters. Calculations of the vibrational frequencies show that the formation of Br2*- and Br2 water clusters induces significant shifts from the normal modes of isolated water. Excited-state calculations are carried out on Br2*-.nH2O clusters following configuration interaction with single electron excitation procedure and UV-VIS absorption profiles are simulated. There is an excellent agreement between the present theoretical UV-VIS spectra of Br2*-.10H2O cluster and the reported transient optical spectra for Br2*- in aqueous solution.

  18. New measurement of BR(D→ρμν)BR(D→Kμν) branching ratio

    Science.gov (United States)

    FOCUS Collaboration; Link, J. M.; Yager, P. M.; Anjos, J. C.; Bediaga, I.; Castromonte, C.; Machado, A. A.; Magnin, J.; Massafferri, A.; de Miranda, J. M.; Pepe, I. M.; Polycarpo, E.; Dos Reis, A. C.; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sánchez-Hernández, A.; Uribe, C.; Vá, F.; Agostino, L.; Cinquini, L.; Cumalat, J. P.; O'Reilly, B.; Segoni, I.; Stenson, K.; Butler, J. N.; Cheung, H. W. K.; Chiodini, G.; Gaines, I.; Garbincius, P. H.; Garren, L. A.; Gottschalk, E.; Kasper, P. H.; Kreymer, A. E.; Kutschke, R.; Wang, M.; Benussi, L.; Bertani, M.; Bianco, S.; Fabbri, F. L.; Pacetti, S.; Zallo, A.; Reyes, M.; Cawlfield, C.; Kim, D. Y.; Rahimi, A.; Wiss, J.; Gardner, R.; Kryemadhi, A.; Chung, Y. S.; Kang, J. S.; Ko, B. R.; Kwak, J. W.; Lee, K. B.; Cho, K.; Park, H.; Alimonti, G.; Barberis, S.; Boschini, M.; Cerutti, A.; D'Angelo, P.; Dicorato, M.; Dini, P.; Edera, L.; Erba, S.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Mezzadri, M.; Moroni, L.; Pedrini, D.; Pontoglio, C.; Prelz, F.; Rovere, M.; Sala, S.; Davenport, T. F.; Arena, V.; Boca, G.; Bonomi, G.; Gianini, G.; Liguori, G.; Lopes Pegna, D.; Merlo, M. M.; Pantea, D.; Ratti, S. P.; Riccardi, C.; Vitulo, P.; Gö, C.; Otalora, J.; Hernandez, H.; Lopez, A. M.; Mendez, H.; Paris, A.; Quinones, J.; Ramirez, J. E.; Zhang, Y.; Wilson, J. R.; Handler, T.; Mitchell, R.; Engh, D.; Hosack, M.; Johns, W. E.; Luiggi, E.; Moore, J. E.; Nehring, M.; Sheldon, P. D.; Vaandering, E. W.; Webster, M.; Sheaff, M.

    2006-06-01

    Using data collected by the FOCUS experiment at Fermilab, we present a new measurement of the charm semileptonic branching ratio BR(D→ρμν)BR(D→Kμν). From a sample of 320±44 and 11372±161D→ρμν and D→Kπμν events respectively, we find BR(D→ρμν)BR(D→Kμν)=0.041±0.006 (stat)±0.004 (syst).

  19. Refurbishing the BR2 materials testing reactor

    International Nuclear Information System (INIS)

    Baugnet, J.M.; Dekeyser, J.; Gubel, P.

    1995-01-01

    SCK/CEN is refurbishing its BR2 reactor to allow its further operation during the next 15 years; in doing so, it chooses to keep BR2 available for future scientific and technological irradiation programs within an international context. (author) 2 figs

  20. Excitation functions and yields of proton induced reactions at intermediate energies leading to important diagnostics radioisotopes of {sup 52}Fe, {sup 77}Br, {sup 82}Rb, {sup 97}Ru, {sup 111}In, {sup 123}I, {sup 127}Xe, {sup 128}Cs, {sup 178}Ta and {sup 201}Tl

    Energy Technology Data Exchange (ETDEWEB)

    Rurarz, E. [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland)

    1994-12-31

    This report describes investigations of the excitation functions of the proton induced reactions on 14 targets (Mn, Co, Br, Rb, {sup 99}Tc, {sup 113}Cd, {sup 114}Cd, Cd, I, Cs, Ta, {sup 206,207,208}Pb) leading directly or indirectly to the formation of radionuclides {sup 52}Fe, {sup 77}Br, {sup 82}Rb, {sup 97}Ru, {sup 111}In, {sup 123}I, {sup 127}Xe, {sup 128}Cs, {sup 178}Ta and {sup 201}Tl frequently used in diagnostic procedures of nuclear medicine. The measurements of the excitation functions were made over a wide proton energy range from the reaction threshold up to 100 MeV using the stacked foil (or pellet) technique. Small energy steps were used to allow for accurate determination of the structure of excitation functions. For {sup 97}Ru, {sup 111}In and {sup 127}Xe formation with protons, new reaction channels and targets were used and data concerning this method are published for the first time. The data for {sup 52}Fe, {sup 77}Br, {sup 82}Rb, {sup 123}I, {sup 128}Cs and {sup 201}Tl obtained in the present work for the E{sub p}=70-100 MeV region are also published for the first time. The measured excitation functions for the formation of desired (and undesired) radionuclides (altogether 28 excitation functions) are compared with the theoretical ones calculated on the basis of a hybrid model of nuclear reactions in the form of the Overlaid Alice computer code. In order to determine the contribution of the competitive reaction channels to the purity of the produced, desired radionuclide, the excitation functions of the accompanying reactions were also calculated. The 122 calculated excitation functions for the possible contaminant are given. The comparison of experimental excitation functions with the results of model calculations showed satisfactory agreement; no parameter adjustment for individual reaction products was undertaken. Production yields for 28 radionuclides mentioned above were determined (author). 262 refs, 65 figs, 34 tabs.

  1. Irradiation techniques at BR2 reactor

    International Nuclear Information System (INIS)

    Hebel, W.

    1978-01-01

    Since 1963 the material testing reactor BR2 at Mol is operated for the realisation of numerous research programs and experiments on the behavior of materials under nuclear radiation and in particular under intensive neutron exposure. During this period special irradiation techniques and experimental devices were developed according to the desiderata of the different experiments and to the irradiation possibilities offered at BR2. The design and the operating characteristics of quite a number of those irradiation rigs of proven reliability may be used or can be made available for new irradiation experiments. A brief description is given of some typical irradiation devices designed and constructed by CEN/SCK, Technology and Energy Dpt. They are compiled according to their main use for the different research and development programs realized at BR2. Their eventual application however for different objectives could be possible. A final chapter summarizes the principal irradiation conditions offered by BR2 reactor. (author)

  2. BRIEF COMMUNICATIONS: Optically pumped ultraviolet BR2 laser

    Science.gov (United States)

    Kamrukov, A. S.; Kozlov, N. P.; Protasov, Yu S.; Ushmarov, E. Yu

    1989-12-01

    A report is given of lasing achieved for the first time in optically pumped molecular bromine (D' 3Π2g→A' 3π2u, λL approx 292 nm). It was pumped by thermal vacuum ultraviolet radiation emitted by plasmadynamic discharges of magnetoplasma compressors, formed directly in the laser active medium. An output energy of ~ 1.1 J was obtained per laser pulse of ~ 5-μs duration from a Br2:Ar approx 1:450 active mixture at a pressure of ~ 4 atm. A comparison was made of the experimental output parameters of optically pumped Br2, I2, and XeF (B-X) lasers when their geometries and excitation energies were identical.

  3. Die Interhalogenkationen [Br2F5]+ und [Br3F8].

    Science.gov (United States)

    Ivlev, Sergei; Karttunen, Antti; Buchner, Magnus; Conrad, Matthias; Kraus, Florian

    2018-05-02

    Wir berichten über die Synthese und Charakterisierung der bislang einzigen Polyhalogenkationen, in denen verbrückende Fluoratome vorliegen. Das [Br2F5]+-Kation enthält eine symmetrische [F2Br-µ-F-BrF2]-Brücke, das [Br3F8]+-Kation enthält unsymmetrische µ-F-Brücken. Die Fluoronium-Ionen wurden in Form ihrer [SbF6]--Salze erhalten und Raman-, und 19F-NMR-spektroskopisch, sowie durch Röntgenbeugung am Einkristall untersucht. Quantenchemische Rechnungen, sowohl für die isolierten Kationen in der Gasphase, als auch für die Festkörper selbst, wurden durchgeführt. Populationsanalysen zeigen, dass die µ-F-Atome die am stärksten negativ partialgeladenen Atome der Kationen sind. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Preparation of 80Br or 82Br-biomolecules via excitation labelling methods

    International Nuclear Information System (INIS)

    Wong, S.; Ache, H.J.

    1975-01-01

    The direct decay-induced 82 Br (or 80 Br) labelling by exposing the solid substrate molecules, such as deoxyuridine, L-tyrosine, guanosine, deoxycytidine, phenylalanine, and acetic acid, to gaseous CF 3 82 /sup m/Br (or CF 3 80 /sup m/Br) was studied. The radiochemical yields of the brominated products are relatively small and range from 1 percent in the case of bromo deoxyuridine to 11 percent for bromoacetic acid. The modification of this technique by adding Cl 2 gas to the reaction mixture improves the yields in several cases drastically (up to 80 percent for bromo-guanosine and bromo-L-tyrosine). Similar improvement can be achieved by exposing crystalline KBrO 3 for some time to CF 3 82 /sup m/Br (or CF 3 80 /sup m/Br) and dissolving subsequently the KBrO 3 in an acidic solution of the substrate. (auth)

  5. Origin of enhanced Brønsted acidity of NiF-modified synthetic mica-montmorillonite clay

    NARCIS (Netherlands)

    Liu, C.; Pidko, E.A.; Hensen, Emiel J M

    2018-01-01

    The Brønsted acidity of synthetic mica-montmorillonite (SMM) clay was studied by periodic DFT calculations. Different structural models were compared to determine the Brønsted acidity of protons of the SMM clay based on (i) isomorphous substitution of Si4+ by Al3+ in the

  6. Origin of enhanced Brønsted acidity of NiF-modified synthetic mica-montmorillonite clay

    NARCIS (Netherlands)

    Liu, Chong; Pidko, Evgeny A.; Hensen, Emiel J.M.

    2018-01-01

    The Brønsted acidity of synthetic mica-montmorillonite (SMM) clay was studied by periodic DFT calculations. Different structural models were compared to determine the Brønsted acidity of protons of the SMM clay based on (i) isomorphous substitution of Si4+ by Al3+ in the tetrahedral silicate layer

  7. Improved Syntheses and Expanded Analyses of the Enantiomerically Enriched Chiral Cobalt Complexes Co(en)[subscript 3]I[subscript 3] and Co(diNOsar)Br[subscript 3

    Science.gov (United States)

    McClellan, Michael J.; Cass, Marion E.

    2015-01-01

    This communication is a collection of additions and modifications to two previously published classic inorganic synthesis laboratory experiments. The experimental protocol for the synthesis and isolation of enantiomerically enriched ?- (or ?-)Co(en)[subscript 3]I[subscript 3] has been modified to increase reproducibility, yield, and enantiomeric…

  8. Solvation dynamics through Raman spectroscopy: hydration of Br2 and Br3(-), and solvation of Br2 in liquid bromine.

    Science.gov (United States)

    Branigan, Edward T; Halberstadt, N; Apkarian, V A

    2011-05-07

    Raman spectroscopy of bromine in the liquid phase and in water illustrates uncommon principles and yields insights regarding hydration. In liquid Br(2), resonant excitation over the B((3)Π(0u)(+)) ← X((1)Σ(g)(+)) valence transition at 532 nm produces a weak resonant Raman (RR) progression accompanied by a five-fold stronger non-resonant (NR) scattering. The latter is assigned to pre-resonance with the C-state, which in turn must be strongly mixed with inter-molecular charge transfer states. Despite the electronic resonance, RR of Br(2) in water is quenched. At 532 nm, the homogeneously broadened fundamental is observed, as in the NR case at 785 nm. The implications of the quenching of RR scattering are analyzed in a simple, semi-quantitative model, to conclude that the inertial evolution of the Raman packet in aqueous Br(2) occurs along multiple equivalent water-Br(2) coordinates. In distinct contrast with hydrophilic hydration in small clusters and hydrophobic hydration in clathrates, it is concluded that the hydration shell of bromine in water consists of dynamically equivalent fluxional water molecules. At 405 nm, the RR progression of Br(3)(-) is observed, accompanied by difference transitions between the breathing of the hydration shell and the symmetric stretch of the ion. The RR scattering process in this case can be regarded as the coherent photo-induced electron transfer to the solvent and its radiative back-transfer.

  9. Thermodynamics of the amalgam cells {l_brace}Cs-amalgam|CsX (m)|AgX|Ag{r_brace} (X=Cl, Br, I) and primary medium effects in (methanol+water) (acetonitrile+water), and (1,4-dioxane+water) solvent mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Falciola, Luigi [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy)]. E-mail: luigi.falciola@unimi.it; Longoni, Giorgio [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy); Mussini, Patrizia R. [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy)]. E-mail: patrizia.mussini@unimi.it; Mussini, Torquato [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy)]. E-mail: torquato.mussini@unimi.it

    2006-06-15

    The potential difference E of the amalgam cell {l_brace}Cs{sub x}Hg{sub 1-x}|CsX (m)|AgX|Ag{r_brace} (X=Cl, Br, I) has been measured as a function of the mole fraction x{sub Cs} of Cs metal in amalgams and of the molality m of CsX in (methanol+water) (acetonitrile+water), and (1,4-dioxane+water) solvent mixtures containing up to 0.75 mass fraction of the organic component, at the temperature 298.15K. The respective standard molal potential differences E{sub m}{sup o} have been determined together with the relevant activity coefficients {gamma}{sub +}/- as functions of the CsX molality. The found E{sub m}{sup o} values show a parabolic decrease with increasing proportion of the organic component in the solvent mixture. Analysis of the relevant primary medium effects upon CsX shows that the CsX transfer from the standard state in water to the standard state in the (aqueous+organic) mixture is always unfavoured, and the acetonitrile is the least unfavoured co-solvent studied. Analysis of the primary medium effect upon CsI in terms of Feakins and French's theory leads to a primary hydration number close to zero, which is consistent with the results of supplementary EXAFS experiments on Cs{sup +} and I{sup -} in (acetonitrile+water) solvent mixtures.

  10. Mellem brødre

    DEFF Research Database (Denmark)

    mindst betydningen af den kulturelle union, som eksisterede mellem de to lande frem til begyndelsen af 1900-tallet. Samtidig med at København i næsten 100 år vedblev at være Norges kulturelle hovedstad, spillede norske kunstnere som Henrik Ibsen, Bjørnstjerne Bjørnson og Edvard Grieg en afgørende rolle...

  11. Radiative forcing calculations for CH3Br

    International Nuclear Information System (INIS)

    Grossman, A.S.; Blass, W.E.; Wuebbles, D.J.

    1995-06-01

    Methyl Bromide, CH 3 Br, is the major organobromine species in the lower atmosphere and is a primary source of bromine in the stratosphere. It has a lifetime of 1.3 years. The IR methyl bromide spectra in the atmospheric window region, 7--13μ, was determined using a well tested Coriolis resonance and ell-doubling (and ell-resonance) computational system. A radiative forcing value of 0.00493 W/m 2 /ppbv was obtained for CH 3 Br and is approximately linear in the background abundance. This value is about 2 percent of the forcing of CFC-11 and about 278 times the forcing of C0 2 , on a per molecule basis. The radiative forcing calculation is used to estimate the global warming potential (GWP) of CH 3 Br. The results give GWPs for CH 3 Br of the order of 13 for an integration period of 20 years and 4 for an integration period of 100 years (assuming C0 2 = 1, following IPCC [1994]). While CH 3 Br has a GWP which is approximately 25 percent of the GWP of CH 4 , the current emission rates are too low to cause serious atmospheric greenhouse heating effects at this time

  12. Improved production of Br atoms near zero speed by photodissociating laser aligned Br2 molecules.

    Science.gov (United States)

    Deng, L Z; Yin, J P

    2014-10-28

    We theoretically investigated the improvement on the production rate of the decelerated bromine (Br) atoms near zero speed by photodissociating laser aligned Br2 precursors. Adiabatic alignment of Br2 precursors exposed to long laser pulses with duration on the order of nanoseconds was investigated by solving the time-dependent Schrödinger equation. The dynamical fragmentation of adiabatically aligned Br2 precursors was simulated and velocity distribution of the Br atoms produced was analyzed. Our study shows that the larger the degree of the precursor alignment, ⟨cos(2) θ⟩, the higher the production rate of the decelerated Br atoms near zero speed. For Br2 molecules with an initial rotational temperature of ~1 K, a ⟨cos(2) θ⟩ value of ~0.88 can result in an improvement factor of over ~20 on the production rate of the decelerated Br atoms near zero speed, requiring a laser intensity of only ~1 × 10(12) W/cm(2) for alignment.

  13. Rate constant for the reaction SO + BrO yields SO2 + Br

    Science.gov (United States)

    Brunning, J.; Stief, L.

    1986-01-01

    The rate of the radical-radical reaction SO + BrO yields SO2 + Br has been determined at 298 K in a discharge flow system near 1 torr pressure with detection of SO and BrO via collision-free sampling mass spectrometry. The rate constant was determined using two different methods: measuring the decay of SO radicals in the presence of an excess of BrO and measuring the decay of BrO radicals in excess SO. The results from the two methods are in reasonable agreement and the simple mean of the two values gives the recommended rate constant at 298 K, k = (5.7 + or - 2.0) x 10 to the -11th cu cm/s. This represents the first determination of this rate constant and it is consistent with a previously derived lower limit based on SO2 formation. Comparison is made with other radical-radical reactions involving SO or BrO. The reaction SO + BrO yields SO2 + Br is of interest for models of the upper atmosphere of the earth and provides a potential coupling between atmospheric sulfur and bromine chemistry.

  14. Bromine-rich Zinc Bromides: Zn6Br12(18-crown-6)2×(Br2)5, Zn4Br8(18-crown-6)2×(Br2)3, and Zn6Br12(18-crown-6)2×(Br2)2.

    Science.gov (United States)

    Hausmann, David; Feldmann, Claus

    2016-06-20

    The bromine-rich zinc bromides Zn6Br12(18-crown-6)2×(Br2)5 (1), Zn4Br8(18-crown-6)2×(Br2)3 (2), and Zn6Br12(18-crown-6)2×(Br2)2 (3) are prepared by reaction of ZnBr2, 18-crown-6, and elemental bromine in the ionic liquid [MeBu3N][N(Tf)2] (N(Tf)2 = bis(trifluoromethylsulfonyl)amide). Zn6Br12(18-crown-6)2×(Br2)5 (1) is formed instantaneously by the reaction. Even at room temperature, compound 1 releases bromine, which was confirmed by thermogravimetry (TG) and mass spectrometry (MS). The release of Br2 can also be directly followed by the color and density of the title compounds. With controlled conditions (2 weeks, 25 °C, absence of excess Br2) Zn6Br12(18-crown-6)2×(Br2)5 (1) slowly releases bromine with conconcurrent generation of Zn4Br8(18-crown-6)2×(Br2)3 (2) (in ionic liquid) and Zn6Br12(18-crown-6)2×(Br2)2 (3) (in inert oil). All bromine-rich zinc bromides contain voluminous uncharged (e.g., Zn3Br6(18-crown-6), Zn2Br4(18-crown-6)) or ionic (e.g., [Zn2Br3(18-crown-6)](+), [(Zn2Br6)×(Br2)2](2-)) building units with dibromine molecules between the Zn oligomers and partially interconnecting the Zn-containing building units. Due to the structural similarity, the bromine release is possible via crystal-to-crystal transformation with retention of the crystal shape.

  15. Børnepenge og Brøkpension

    DEFF Research Database (Denmark)

    Blaakilde, Anne Leonora

    2014-01-01

    Børnecheckdebatten har raset om EU-borgeres ret til danske børnepenge, og om velfærdsydelser i det hele taget. I en øget globaliseret verden er der pres på nationale grænser og deres historiske funktion med at fastholde rammer for fællesskaber, som er solidariske over for nogen, i og med de ekskl...... ekskluderer andre. Diskussionerne handler dog også om aldersgrupper: Om børn og voksne arbejdstagere. Én aldersgruppe blev helt overset i spalterne; pensionisterne. Kulturforsker Anne Leonora Blaakilde skriver om det 41 år gamle, men forholdsvis ukendte fænomen brøkpension...

  16. Production of 77 Br for medical application

    International Nuclear Information System (INIS)

    Bastos, M.A.V.

    1982-01-01

    Bromine-77 is produced with the variable energy cyclotron (CV-28) at the Instituto de Engenharia Nuclear, via the 75 As. (α, 2 n) 77 Br reaction, by bombarding arsenic trioxide with 28 MeV alpha-particles. The thick target yield is 0.3 mCi/μAh. The target is dissolved in concentrated N H 4 OH and 77 Br, separated from arsenic, by an anionic exchange resin, is obtained carrier-free with a separation yield greater than 90%. All the process is remotely controlled using electric and pneumatic systems, manipulators and tongs. The quality control is made by atomic absorption and gamma-ray spectroscopy. The present production rate of Br-77 is 2.3 mCi per irradiation. (author)

  17. Status of the BR2 refurbishment programme

    International Nuclear Information System (INIS)

    Koonen, E.

    1995-01-01

    The operation of the BR2 reactor with its second beryllium matrix is foreseen up to mid-1995. A refurbishment programme has been established in order to allow for future operation during at least ten years. Recently a positive decision to effectively carry out this programme has been taken. The refurbishment action plan follows from a general assessment of the different systems of BR2, with respect to their actual status, the operational experience and the evolution of safety standards and criteria. Ageing considerations were of uppermost importance in those assessments, not only to assure safety of future operation, but also to guarantee future availability and reliability. (orig.)

  18. Palveluprosessi toimivaksi, Case: BR-Lelut

    OpenAIRE

    Korpela, Jenni

    2014-01-01

    Tämä opinnäytetyö on tehty toimeksiantona TOP-TOY A/S –konserniin kuluvalle lelumyymäläketju BR-Leluille Suomessa. Opinnäyte on toteutettu produktiluontoisena ja sen tuloksena on syntynyt Asiakaspalvelun ja myynnin käsikirja BR-Lelujen myymälähenkilökunnalle. Ajatus opinnäytetyölle ja eritoten käsikirjalle syntyi, kun kirjoittaja työskenteli kyseisen myymäläketjun myymälässä ja samanaikaisesti opiskeli erilaisia myyntitekniikoita ammattikorkeakoulussa. Kirjoittaja huomasi, että myyntihen...

  19. Kvantifisering av overvann: Case Brøset

    OpenAIRE

    Huurnink, Jon Egenberg

    2012-01-01

    Oppgaven forsøker å vise den systemresponsen som er særegen for konvensjonelle tiltak og blå-grønne tiltak. Dette er aktuelt på Brøset bydel som en del av Fremtiden byer prosjektet og skal bygges om til boligområde. MIKE URBAN og MIKE 21 er benyttet til å lage en konseptuell modell.Ved å sammenligne sommer- og vinterforhold, i tillegg til ulike gjentaksintervaller (1, 20 og 100år), vil kurver for videreført vannmengde gi et inntrykk av tiltakenes effekt. Dette gir beslutningsstøtte for Komm...

  20. Taxonomic revision of Asian genus Glyptopetalum Thwaites (Celastraceae R. Br.

    Directory of Open Access Journals (Sweden)

    Ivan A. Savinov

    2014-12-01

    Full Text Available Taxonomic survey of Asian genus Glyptopetalum Thwaites (Celastraceae R. Br. is presented. Thirty five species taxa of Glyptopetalum are accepted, including one new species, G.  vidalii I. Savinov (Laos, Thailand, a new record for China, G. tonkinense Pitard (SE Yunnan and a new record for Cambodia,               G. quadrangulare Prain ex King, a new record for Indonesia – G. euonymoides Merr. and a new record for Philippines, Mindanao island – G. loheri Merr. 

  1. Influence of the Li···π Interaction on the H/X···π Interactions in HOLi···C6H6···HOX/XOH (X=F, Cl, Br, I) complexes.

    Science.gov (United States)

    Zeng, Yanli; Wu, Wenjie; Li, Xiaoyan; Zheng, Shijun; Meng, Lingpeng

    2013-06-03

    The influences of the Li···π interaction of C6H6···LiOH on the H···π interaction of C6H6···HOX (X=F, Cl, Br, I) and the X···π interaction of C6H6···XOH (X=Cl, Br, I) are investigated by means of full electronic second-order Møller-Plesset perturbation theory calculations and "quantum theory of atoms in molecules" (QTAIM) studies. The binding energies, binding distances, infrared vibrational frequencies, and electron densities at the bond critical points (BCPs) of the hydrogen bonds and halogen bonds prove that the addition of the Li···π interaction to benzene weakens the H···π and X···π interactions. The influences of the Li···π interaction on H···π interactions are greater than those on X···π interactions; the influences of the H···π interactions on the Li···π interaction are greater than X···π interactions on Li···π interaction. The greater the influence of Li···π interaction on H/X···π interactions, the greater the influences of H/X···π interactions on Li···π interaction. QTAIM studies show that the intermolecular interactions of C6H6···HOX and C6H6···XOH are mainly of the π type. The electron densities at the BCPs of hydrogen bonds and halogen bonds decrease on going from bimolecular complexes to termolecular complexes, and the π-electron densities at the BCPs show the same pattern. Natural bond orbital analyses show that the Li···π interaction reduces electron transfer from C6 H6 to HOX and XOH. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. The TbBr3–LiBr binary system: Experimental thermodynamic investigation and assessment of phase diagram

    International Nuclear Information System (INIS)

    Rycerz, L.; Gong, W.; Gaune-Escard, M.

    2013-01-01

    Highlights: ► DSC measurements for the (LiBr + TbBr 3 ) system. ► congruently Li3TbBr 6 and incongruently melting Li5TbBr 8 compounds. ► Thermodynamic description of the liquid phase in the (LiBr + TbBr 3 ) system. ► Assessment with a two-sublattice ionic solution model. - Abstract: DSC was used to study the phase equilibrium in the TbBr 3 –LiBr binary system. The results obtained provided a basis for constructing the phase diagram of this system. It exhibits two compounds: Li 5 TbBr 8 , which decomposes in the solid state at 611 K, and Li 3 TbBr 6 , which melts congruently at 785 K with the related enthalpy 59.1 kJ·mol −1 . The binary LiBr–TbBr 3 system was then optimized using the available experimental information on phase diagram and thermodynamic properties. A two-sub-lattice ionic solution model (Li + ) P :(Br − , TbBr 6 −3 , TbBr 3 ) Q was adopted to describe the liquid phase. The present assessment of the binary LiBr–TbBr 3 system was in good agreement with the corresponding experimental data and confirmed their consistency.

  3. Matrix isolation and computational study of isodifluorodibromomethane (F2CBr-Br): a route to Br2 formation in CF2Br2 photolysis.

    Science.gov (United States)

    George, Lisa; Kalume, Aimable; El-Khoury, Patrick Z; Tarnovsky, Alexander; Reid, Scott A

    2010-02-28

    The photolysis products of dibromodifluoromethane (CF(2)Br(2)) were characterized by matrix isolation infrared and UV/Visible spectroscopy, supported by ab initio calculations. Photolysis at wavelengths of 240 and 266 nm of CF(2)Br(2):Ar samples (approximately 1:5000) held at approximately 5 K yielded iso-CF(2)Br(2) (F(2)CBrBr), a weakly bound isomer of CF(2)Br(2), which is characterized here for the first time. The observed infrared and UV/Visible absorptions of iso-CF(2)Br(2) are in excellent agreement with computational predictions at the B3LYP/aug-cc-pVTZ level. Single point energy calculations at the CCSD(T)/aug-cc-pVDZ level on the B3LYP optimized geometries suggest that the isoform is a minimum on the CF(2)Br(2) potential energy surface, lying some 55 kcal/mol above the CF(2)Br(2) ground state. The energies of various stationary points on the CF(2)Br(2) potential energy surface were characterized computationally; taken with our experimental results, these show that iso-CF(2)Br(2) is an intermediate in the Br+CF(2)Br-->CF(2)+Br(2) reaction. The photochemistry of the isoform was also investigated; excitation into the intense 359 nm absorption band resulted in isomerization to CF(2)Br(2). Our results are discussed in view of the rich literature on the gas-phase photochemistry of CF(2)Br(2), particularly with respect to the existence of a roaming atom pathway leading to molecular products.

  4. Bellahøj. Ballerup. Brøndby Strand

    DEFF Research Database (Denmark)

    Bertelsen, S.

    I maj 1945 var forventningerne store, og alle så frem til at "der snart ville komme en båd med bananer". Det gjaldt ikke mindst for byggeriet, som så frem til at afhjælpe den store boligmangel. Det tog tid, men opgaven blev løst - gennem udvikling og industrialisering. Byggeriets udvikling - især...... det der skete? Hvem tog initiativet? Hvorfor lykkedes det med så stor succes, som det faktisk gjorde? Hvilke tanker, idealer og indgreb var udgangspunkt for den store indsats? På grundlag af disse spørgsmål har Sven Bertelsen i "Bellahøj - Ballerup - Brøndby Strand" skildret en væsentlig epoke i dansk...

  5. Elamusturundus: riigi brändimine ja Eesti bränd / Siiri Same

    Index Scriptorium Estoniae

    Same, Siiri

    2015-01-01

    Artikli autor oma 2015. a. Tallinna Tehnikaülikoolis kaitstud doktoritööst "Conceptualization of experience marketing and country branding from a marketing management perspective" ("Elamusturunduse ja riigi brändimise kontseptualiseerimine turunduse juhtimise vaatenurgast")

  6. $^{80m}$Br/$^{80}$Br a new electron-$\\gamma$ - PAC Probe

    CERN Document Server

    Correia, J G; Araújo, J P; Marques, J G; Soares, J C; Melo, A A

    2001-01-01

    Conversion electron-$\\gamma$ PAC measurements of the 49 keV - 37 keV cascade in $^{80}$Br through the intermediate 2$^{-}$ state with T$_{1/2}$=7.4 ns were performed with a system of two magnetic lens spectrometers and two BaF$_{2}$ scintillation detectors. The parent $^{80m}$Br activity with half-life of 4.4 hrs was implanted into Ni, Zn and graphite at the ISOLDE separator at CERN. The observed interaction frequency in the nickel matrix is in good agreement with the known value of the hyperfine field for Br in Ni and the magnetic moment of the 2$^{-}$ state. From the measured quadrupole interaction in Zn and graphite the electric field gradients at Br were obtained.

  7. $^{80}$Br $^{80}$Br-a new electron-gamma PAC probe

    CERN Document Server

    Correia, J G; Araújo, J P; Marques, J G; Soares, J C; Melo, A A

    2001-01-01

    Conversion electron-gamma PAC measurements of the 49-37 keV cascade in /sup 80/Br through the intermediate 2/sup -/ state with T/sub 1/2 /=7.4 ns were performed with a system of two magnetic lens spectrometers and two BaF/sub 2/ scintillation detectors. The parent /sup 80m/Br activity with a halflife of 4.4 hrs was implanted into Ni, Zn and graphite at the ISOLDE separator at CERN. The observed interaction frequency in the nickel matrix is in good agreement with the known value of the hyperfine field for Br in Ni and the magnetic moment of the 2/sup -/ state. From the measured quadrupole interaction in Zn and graphite the electric field gradients at Br were obtained. (7 refs).

  8. Lead-free Perovskite Materials (NH4 )3 Sb2 Ix Br9-x.

    Science.gov (United States)

    Zuo, Chuantian; Ding, Liming

    2017-06-01

    A family of perovskite light absorbers (NH 4 ) 3 Sb 2 I x Br 9-x (0≤x≤9) was prepared. These materials show good solubility in ethanol, a low-cost, hypotoxic, and environmentally friendly solvent. The light absorption of (NH 4 ) 3 Sb 2 I x Br 9-x films can be tuned by adjusting I and Br content. The absorption onset for (NH 4 ) 3 Sb 2 I x Br 9-x films changes from 558 nm to 453 nm as x changes from 9 to 0. (NH 4 ) 3 Sb 2 I 9 single crystals were prepared, exhibiting a hole mobility of 4.8 cm 2  V -1  s -1 and an electron mobility of 12.3 cm 2  V -1  s -1 . (NH 4 ) 3 Sb 2 I 9 solar cells gave an open-circuit voltage of 1.03 V and a power conversion efficiency of 0.51 %. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Visible Light Driven Nanosecond Bromide Oxidation by a Ru Complex with Subsequent Br-Br Bond Formation.

    Science.gov (United States)

    Li, Guocan; Ward, William M; Meyer, Gerald J

    2015-07-08

    Visible light excitation of [Ru(deeb)(bpz)2](2+) (deeb = 4,4'-diethylester-2,2'-bipyridine; bpz = 2,2'-bipyrazine), in Br(-) acetone solutions, led to the formation of Br-Br bonds in the form of dibromide, Br2(•-). This light reactivity stores ∼1.65 eV of free energy for milliseconds. Combined (1)H NMR, UV-vis and photoluminescence measurements revealed two distinct mechanisms. The first involves diffusional quenching of the excited state by Br(-) with a rate constant of (8.1 ± 0.1) × 10(10) M(-1) s(-1). At high Br(-) concentrations, an inner-sphere pathway is dominant that involves the association of Br(-), most likely with the 3,3'-H atoms of a bpz ligand, before electron transfer from Br(-) to the excited state, ket = (2.5 ± 0.3) × 10(7) s(-1). In both mechanisms, the direct photoproduct Br(•) subsequently reacts with Br(-) to yield dibromide, Br(•) + Br(-) → Br2(•-). Under pseudo-first-order conditions, this occurs with a rate constant of (1.1 ± 0.4) × 10(10) M(-1) s(-1) that was, within experimental error, the same as that measured when Br(•) were generated with ultraviolet light. Application of Marcus theory to the sensitized reaction provided an estimate of the Br(•) formal reduction potential E(Br(•)/Br(-)) = 1.22 V vs SCE in acetone, which is about 460 mV less positive than the accepted value in H2O. The results demonstrate that Br(-) oxidation by molecular excited states can be rapid and useful for solar energy conversion.

  10. Matrix isolation and computational study of isodifluorodibromomethane (F2CBr-Br): A route to Br2 formation in CF2Br2 photolysis

    International Nuclear Information System (INIS)

    George, Lisa; Kalume, Aimable; Reid, Scott A.; El-Khoury, Patrick Z.; Tarnovsky, Alexander

    2010-01-01

    The photolysis products of dibromodifluoromethane (CF 2 Br 2 ) were characterized by matrix isolation infrared and UV/Visible spectroscopy, supported by ab initio calculations. Photolysis at wavelengths of 240 and 266 nm of CF 2 Br 2 :Ar samples (∼1:5000) held at ∼5 K yielded iso-CF 2 Br 2 (F 2 CBrBr), a weakly bound isomer of CF 2 Br 2 , which is characterized here for the first time. The observed infrared and UV/Visible absorptions of iso-CF 2 Br 2 are in excellent agreement with computational predictions at the B3LYP/aug-cc-pVTZ level. Single point energy calculations at the CCSD(T)/aug-cc-pVDZ level on the B3LYP optimized geometries suggest that the isoform is a minimum on the CF 2 Br 2 potential energy surface, lying some 55 kcal/mol above the CF 2 Br 2 ground state. The energies of various stationary points on the CF 2 Br 2 potential energy surface were characterized computationally; taken with our experimental results, these show that iso-CF 2 Br 2 is an intermediate in the Br+CF 2 Br→CF 2 +Br 2 reaction. The photochemistry of the isoform was also investigated; excitation into the intense 359 nm absorption band resulted in isomerization to CF 2 Br 2 . Our results are discussed in view of the rich literature on the gas-phase photochemistry of CF 2 Br 2 , particularly with respect to the existence of a roaming atom pathway leading to molecular products.

  11. Pharmacological characterization of BR-A-657, a highly potent nonpeptide angiotensin II receptor antagonist.

    Science.gov (United States)

    Chi, Yong Ha; Lee, Joo Han; Kim, Je Hak; Tan, Hyun Kwang; Kim, Sang Lin; Lee, Jae Yeol; Rim, Hong-Kun; Paik, Soo Heui; Lee, Kyung-Tae

    2013-01-01

    The pharmacological profile of BR-A-657, 2-n-butyl-5-dimethylamino-thiocarbonyl-methyl-6-methyl-3-{[2-(1H-tetrazole-5-yl)biphenyl-4-yl]methyl}-pyrimidin-4(3H)-one, a new nonpeptide AT1-selective angiotensin receptor antagonist, has been investigated in a variety of in vitro and in vivo experimental models. In the present study, BR-A-657 displaced [(125)I][Sar(1)-Ile(8)]angiotensin II (Ang II) from its specific binding sites to AT1 subtype receptors in membrane fractions of HEK-293 cells with an IC50 of 0.16 nM. In a functional assay using isolated rabbit thoracic aorta, BR-A-657 inhibited the contractile response to Ang II (pD'2: 9.15) with a significant reduction in the maximum. In conscious rats, BR-A-657 (0.01, 0.1, 1 mg/kg; intravenously (i.v.)) dose-dependently antagonized Ang II-induced pressor responses. In addition, BR-A-657 dose-dependently decreased mean arterial pressure in furosemide-treated rats and renal hypertensive rats. Moreover, BR-A-657 given orally at 1 and 3 mg/kg reduced blood pressure in conscious renal hypertensive rats. Taken together, these findings indicate that BR-A-657 is a potent and specific antagonist of Ang II at the AT1 receptor subtype, and reveal the molecular basis responsible for the marked lowering of blood pressure in conscious rats.

  12. Revised and extended analysis of Br IV

    International Nuclear Information System (INIS)

    Riyaz, A.; Rahimullah, K.; Tauheed, A.

    2014-01-01

    The spectrum of three-times ionized bromine Br IV has been studied in the 319–2350 Å wavelength region. The spectrum was recorded on a 3-m normal incidence vacuum spectrograph at the St. Francis Xavier University, Antigonish (Canada) and 6.65-m grazing incidence spectrograph at the Zeeman laboratory (Amsterdam). The light sources used were a triggered spark and sliding spark, respectively. The ground configuration of Br IV 3d 10 4s 2 4p 2 , the excited configurations 3d 10 4s4p 3 +3d 10 4s 2 4p (4d+5d+6d+5s+6s+7s) in the odd parity system and 3d 10 4s 2 4p (5p+4f+5f)+3d 10 4s4p 2 (4d+5s)+3d 10 4p 4 in the even parity system have been studied. Relativistic Hartree–Fock (HFR) and least squares fitted (LSF) parametric calculations were used to interpret the observed spectrum. 120 Levels of Br IV have now been established, 58 being new. Among 424 spectral lines, 277 are newly classified. The levels 4s4p 35 S 2 , 4s 2 4p4d 3 F 4 and 4p5p ( 3 P 0,1 , 3 D 1,2 , 3 S 1 ) are revised. We estimate the accuracy of our measured wavelength for sharp and unblended lines to be ±0.005 Å. The ionization limit is determined as 385,390±100 cm −1 (47.782±0.012 eV). -- Highlights: • The spectrum of Br was recorded on a 3-m spectrograph with triggered spark source. • Atomic transitions for Br IV were identified to established new energy levels. • CI calculations with relativistic corrections were made for theoretical predictions. • Weighted oscillator strength (gf) and transition probabilities (gA) were calculated. • Ionization potential of Br IV was determined experimentally

  13. Light-emitting diodes based on two-dimensional PA2(CsPbBr3)n-1PbBr4 layered perovskites%基于PA2(CsPbBr3)n-1PbBr4二维层状钙钛矿的电致发光二极管

    Institute of Scientific and Technical Information of China (English)

    孟妍; 牛连斌; 许龙; 林春燕; 熊自阳; 熊祖洪; 陈平

    2018-01-01

    进一步提高全无机卤铅钙钛矿材料CsPbBr3的发光效率,对制备高效率、高稳定性的电致发光二极管(PeLED)具有重要意义.制备纳米级的钙钛矿量子点,一方面有助于提高激子的束缚能和钙钛矿晶体的荧光效率,另一方面也有利于形成连续、致密的二维层状钙钛矿薄膜.本文采用“原位生长”的策略,将一种具有长链结构的丙基溴化胺(CH3CH2CH2NH3Br,PABr)作为添加剂,与CsPbBr3的前驱体溶液进行共混,得到PA2(CsPbBr3)n-1PbBr4钙钛矿量子点.形成的二维层状钙钛矿薄膜均匀致密,在光致发光条件下,呈现出明亮的蓝绿光发射(发光峰位于506 nm).在电致发光方面,基于PA2(CsPbBr3)n-1PbBr4的PeLED启亮电压为~4.2 V,最大亮度为~2370 cd/m2,最高电流效率为~1.06 cd/A,最高EQE为~0.57%.相较于传统方法,本工作在制作工艺、成膜质量以及PeLED的发光效率有了显著的提升,为将来进一步探索低成本、高效率的蓝光PeLEDs提供了一种可行的思路.%Solution-processed organometal halide perovskites (formulated as ABX3,where A is the methylammonium (CH3NH3+)(MA) or metal cesium cation (Cs+),B is the lead cation (Pb2+) and X is the halide anion (Br-,I-,Cl-)) are promising candidates for next generation light-emitting materials owing to their unique optoelectronic properties.These properties mainly include extremely high photoluminescence quantum yield (PLQY),easily tunable band gap and narrow emission characteristics.During the past two years,impressive progresses have been made in perovskite light-emitting diodes (PeLED) with hybrid organic-inorganic perovskite materials (i.e.,CH3NH3PbBr3).So far,the best external quantum efficiency (EQE) of CH3NH3PbBr3-based PeLED was reaching up to ~8.53% which was close to the results of organic light-emitting diodes (OLED).Despite the remarkable performance of the devices demonstrated,the stability of organic-inorganic hybrid perovskites

  14. Inner shell transitions of BrI in the EUV

    Energy Technology Data Exchange (ETDEWEB)

    Mazzoni, M [Florence Univ. (Italy). Ist. di Astronomia; Pettini, M [Osservatorio Astrofisico di Arcetri, Florence (Italy)

    1981-10-12

    The EUV line spectrum originating from transitions of the inner 3d shell of neutral atomic bromine has been observed in absorption. Fano parameters have been derived for the three autoionized resonances nd/sup 10/(n + 1)s/sup 2/(n + 1)p/sup 5/ /sup 2/P-nd/sup 9/(n + 1)s/sup 2/(n + 1)p/sup 62/D observed in both bromine (n = 3) and iodine (n = 4) spectra.

  15. Photostriction of CH3NH3PbBr3 Perovskite Crystals

    KAUST Repository

    Wei, Tzu-Chiao

    2017-07-17

    Organic-inorganic hybrid perovskite materials exhibit a variety of physical properties. Pronounced coupling between phonon, organic cations, and the inorganic framework suggest that these materials exhibit strong light-matter interactions. The photoinduced strain of CH3 NH3 PbBr3 is investigated using high-resolution and contactless in situ Raman spectroscopy. Under illumination, the material exhibits large blue shifts in its Raman spectra that indicate significant structural deformations (i.e., photostriction). From these shifts, the photostrictive coefficient of CH3 NH3 PbBr3 is calculated as 2.08 × 10-8 m2 W-1 at room temperature under visible light illumination. The significant photostriction of CH3 NH3 PbBr3 is attributed to a combination of the photovoltaic effect and translational symmetry loss of the molecular configuration via strong translation-rotation coupling. Unlike CH3 NH3 PbI3 , it is noted that the photostriction of CH3 NH3 PbBr3 is extremely stable, demonstrating no signs of optical decay for at least 30 d. These results suggest the potential of CH3 NH3 PbBr3 for applications in next-generation optical micro-electromechanical devices.

  16. Method of obtaining concentrated preparations of Cl{sup 36} and Br{sup 82} by recoil nuclei under exposure to high-density neutron fields; Preparation de composes du chlore-36 et du brome-82 de haute activite specifique, par exposition de noyaux de recul a des champs neutroniques intenses; Poluchenie kontsentrirovannykh preparatov Cl{sup 36} i Br{sup 82} metodom yader otdachi pri obluchenii v nejtronnykh polyakh vysokoj plotnosti; Obtencion de compuestos de cloro-36 y de bromo-82 de alta actividad especifica por retroceso de nucleos en campos neutronicos intensos

    Energy Technology Data Exchange (ETDEWEB)

    Kurchatova, L N; Kurchatov, B V

    1962-01-15

    resultado de la superposicion de toda una serie de procesos : formacion de atomos de cloro radiactivo, separacion radiolitica del haluro, difusion de los productos obtenidos en la red cristalina del carbono, su sorcion en la superficie y su recombinacion en distintos centros. La extraordinaria variedad de condiciones en que se forman e interaccionan los productos de irradiacion con el esqueleto carbonico y su superficie depende de un gran numero de factores, a saber : la estructura ultramicroscopica, la naturaleza de los nuevos compuestos, que estan relacionados con el tipo de compuestos superficiales, la existencia en la superficie del carbono de centros con un espectro continuo de energia de sorcion, la probable formacion de diversos centros estacionarios de recombinacion por irradiacion del carbono, etc. Por ello, las tecnicas utilizadas ofrecen la posibilidad de realizar una gran variedad de experimentos a fin de establecer las condiciones optimas de enriquecimiento. (author) [Russian] Klassicheskij metod polucheniya kontsentrirovannykh radioaktivnykh preparatov Stsilarda-CHalmersa obychno rassmatrivaetsya kak malo ehffektivnyj pri ispol'zovanii bol'shikh integral'nykh potokov nejtronov iz-za znachitel'nogo razlozheniya obluchaemogo soedineniya pod dejstviem radiatsii. Avtorami najdeny soedineniya broma i khlora s uglerodom, pozvolyayushchie poluchat' sushchestvennoe obogashchenie radioaktivnymi izotopami khlora i broma metodom yader otdachi pri obluchenii v nejtronnykh potokakh poryadka 10{sup 13} nejtr./sek-cm{sup 2}. EHti soedineniya otvechayut formule C{sub n}X, gde X-Cl ili Br, N = 10 + 20 dlya soedineniya khlora i 25 + 70 -dlya soedinenij broma. Oni dostatochno ustojchivy termicheski i khimicheski. Soedinenie sostava C{sub 30}Br vyderzhivaet nagrevanie do 300{sup o}C v atmosfere argona bez otshchepleniya broma; ono razlagaetsya polnost'yu pri temperature 600{sup o}C. Ukazannoe soedinenie broma s uglerodom prakticheski ustojchivo k vozdejstviyu vodnykh rastvorov

  17. Paysans du Brésil

    Directory of Open Access Journals (Sweden)

    Dominique Temple

    2007-01-01

    Full Text Available Eric Sabourin, « Paysans du Brésil : Entre échange marchand et réciprocité » Paris, Editions Quae, 241p, 30 euros, (préface de Maxime Haubert, 2007Dans la présentation du livre, Maxime Haubert dit :«Cet ouvrage propose une analyse socio-anthropologique et agronomique des sociétés rurales et paysannes du Brésil et des transformations qu'elles ont connues ces dernières décennies, en particulier face aux interventions de l'Etat et à l'expansion du marché capitaliste (.... «Le livre pose d'abor...

  18. Molecular elimination of Br2 in photodissociation of CH2BrC(O)Br at 248 nm using cavity ring-down absorption spectroscopy.

    Science.gov (United States)

    Fan, He; Tsai, Po-Yu; Lin, King-Chuen; Lin, Cheng-Wei; Yan, Chi-Yu; Yang, Shu-Wei; Chang, A H H

    2012-12-07

    The primary elimination channel of bromine molecule in one-photon dissociation of CH(2)BrC(O)Br at 248 nm is investigated using cavity ring-down absorption spectroscopy. By means of spectral simulation, the ratio of nascent vibrational population in v = 0, 1, and 2 levels is evaluated to be 1:(0.5 ± 0.1):(0.2 ± 0.1), corresponding to a Boltzmann vibrational temperature of 581 ± 45 K. The quantum yield of the ground state Br(2) elimination reaction is determined to be 0.24 ± 0.08. With the aid of ab initio potential energy calculations, the obtained Br(2) fragments are anticipated to dissociate on the electronic ground state, yielding vibrationally hot Br(2) products. The temperature-dependence measurements support the proposed pathway via internal conversion. For comparison, the Br(2) yields are obtained analogously from CH(3)CHBrC(O)Br and (CH(3))(2)CBrC(O)Br to be 0.03 and 0.06, respectively. The trend of Br(2) yields among the three compounds is consistent with the branching ratio evaluation by Rice-Ramsperger-Kassel-Marcus method. However, the latter result for each molecule is smaller by an order of magnitude than the yield findings. A non-statistical pathway so-called roaming process might be an alternative to the Br(2) production, and its contribution might account for the underestimate of the branching ratio calculations.

  19. Brominated methanes as photoresponsive molecular storage of elemental Br2.

    Science.gov (United States)

    Kawakami, Kazumitsu; Tsuda, Akihiko

    2012-10-01

    The photochemical generation of elemental Br(2) from brominated methanes is reported. Br(2) was generated by the vaporization of carbon oxides and HBr through oxidative photodecomposition of brominated methanes under a 20 W low-pressure mercury lamp, wherein the amount and situations of Br(2) generation were photochemically controllable. Liquid CH(2)Br(2) can be used not only as an organic solvent but also for the photoresponsive molecular storage of Br(2), which is of great technical benefit in a variety of organic syntheses and in materials science. By taking advantage of the in situ generation of Br(2) from the organic solvent itself, many organobromine compounds were synthesized in high practical yields with or without the addition of a catalyst. Herein, Br(2) that was generated by the photodecomposition of CH(2)Br(2) retained its reactivity in solution to undergo essentially the same reactions as those that were carried out with solutions of Br(2) dissolved in CH(2)Br(2) that were prepared without photoirradiation. Furthermore, HBr, which was generated during the course of the photodecomposition of CH(2)Br(2), was also available for the substitution of the OH group for the Br group and for the preparation of the HBr salts of amines. Furthermore, the photochemical generation of Br(2) from CH(2)Br(2) was available for the area-selective photochemical bleaching of natural colored plants, such as red rose petals, wherein Br(2) that was generated photochemically from CH(2)Br(2) was painted onto the petal to cause radical oxidations of the chromophoric anthocyanin molecules. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. PbBr3 Perovskite Crystals

    KAUST Repository

    Wei, Tzu-Chiao; Mokkapati, Sudha; Li, Ting-You; Lin, Chun-Ho; Lin, Gong-Ru; Jagadish, Chennupati; He, Jr-Hau

    2018-01-01

    , such as lithium niobate (LiNbO3), LiTaO3, KTiOPO4, and KH2PO4. Such a strong two-photon absorption effect in CH3NH3PbBr3 can be used to modulate the spectral and spatial profiles of laser pulses, as well as to reduce noise, and can be used to strongly control

  1. Le cas du Brésil

    International Development Research Centre (IDRC) Digital Library (Canada)

    pwust

    important volet des activités de coopération du Brésil dans les pays en développement, ...... attention à l'Amérique latine ou aux Caraïbes, malgré la priorité accordée à .... prudente et sélective face aux opérations triangulaires, afin d'éviter la ...

  2. Production of radioisotopes with BR2 facilities

    International Nuclear Information System (INIS)

    Fallais, C.J.; Morel de Westfaver, A.; Heeren, L.; Baugnet, J.M.; Gandolfo, J.M.; Boeykens, W.

    1978-01-01

    After a brief account on the isotopes production evolution in the industrialized countries the irradiation devices and the types of standardized capsules used in the BR2 reactor are described as well as the thermal neutron flux. Production of most important radioisotopes like 131 Iodine, 60 Cobalt, 192 Iridium and 99 Molybdenum and their main utilizations (uses)are described. The mean specific activities and the limit of use for different radioisotopes are reported. (A.F.)

  3. Decommissioning of the BR3 PWR

    International Nuclear Information System (INIS)

    Massaut, V.

    1998-01-01

    The dismantling and the decommissioning of nuclear installations at the end of their life-cycle is a new challenge to the nuclear industry. Different techniques and procedures for the dismantling of a nuclear power plant on an existing installation, the BR-3 pressurized-water reactor, are described. The scientific program, objectives, achievements in this research area at the Belgian Nuclear Research Centre SCK-CEN for 1997 are summarized

  4. Le CRDI au Brésil

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les recherches subventionnées par le CRDI au Brésil ont permis d'éclairer les débats sur nombre de questions, dont la démocratie, la croissance économique, la santé, les services sociaux, l'innovation, la foresterie et l'eau. Pendant la dictature militaire, qui a pris fin en 1985, le CRDI s'est employé à assurer la survie de la ...

  5. Decommissioning of the BR3 PWR

    International Nuclear Information System (INIS)

    Massaut, V.; Klein, M.

    1998-01-01

    The objectives, programme and main achievements of SCK-CEN's decommissioning programme in 1997 are summarised. Particular emphasis is on the BR3 decommissioning project. In 1997, auxiliary equipment and loops were dismantled; concrete antimissile slabs were decontaminated; the radiology of the primary loop was modelled; the quality assurance procedure for dismantling loops and equipment were implemented; a method for the dismantling of the reactor pressure vessel was selected; and contaminated thermal insulation of the primary loop containing asbestos was removed

  6. PbBr3 Perovskite Crystals

    KAUST Repository

    Wei, Tzu-Chiao

    2018-01-31

    Researchers have recently revealed that hybrid lead halide perovskites exhibit ferroelectricity, which is often associated with other physical characteristics, such as a large nonlinear optical response. In this work, the nonlinear optical properties of single crystal inorganic–organic hybrid perovskite CH3NH3PbBr3 are studied. By exciting the material with a 1044 nm laser, strong two-photon absorption-induced photoluminescence in the green spectral region is observed. Using the transmission open-aperture Z-scan technique, the values of the two-photon absorption coefficient are observed to be 8.5 cm GW−1, which is much higher than that of standard two-photon absorbing materials that are industrially used in nonlinear optical applications, such as lithium niobate (LiNbO3), LiTaO3, KTiOPO4, and KH2PO4. Such a strong two-photon absorption effect in CH3NH3PbBr3 can be used to modulate the spectral and spatial profiles of laser pulses, as well as to reduce noise, and can be used to strongly control the intensity of incident light. In this study, the superior optical limiting, pulse reshaping, and stabilization properties of CH3NH3PbBr3 are demonstrated, opening new applications for perovskites in nonlinear optics.

  7. Expression of NgBR Is Highly Associated with Estrogen Receptor Alpha and Survivin in Breast Cancer

    Science.gov (United States)

    North, Paula; Kong, Amanda; Huang, Jian; Miao, Qing Robert

    2013-01-01

    NgBR is a type I receptor with a single transmembrane domain and was identified as a specific receptor for Nogo-B. Our recent findings demonstrated that NgBR binds farnesylated Ras and recruits Ras to the plasma membrane, which is a critical step required for the activation of Ras signaling in human breast cancer cells and tumorigenesis. Here, we first use immunohistochemistry and real-time PCR approaches to examine the expression patterns of Nogo-B and NgBR in both normal and breast tumor tissues. Then, we examine the relationship between NgBR expression and molecular subtypes of breast cancer, and the roles of NgBR in estrogen-dependent survivin signaling pathway. Results showed that NgBR and Nogo-B protein were detected in both normal and breast tumor tissues. However, the expression of Nogo-B and NgBR in breast tumor tissue was much stronger than in normal breast tissue. The statistical analysis demonstrated that NgBR is highly associated with ER-positive/HER2-negative breast cancer. We also found that the expression of NgBR has a strong correlation with the expression of survivin, which is a well-known apoptosis inhibitor. The correlation between NgBR and survivin gene expression was further confirmed by real-time PCR. In vitro results also demonstrated that estradiol induces the expression of survivin in ER-positive T47D breast tumor cells but not in ER-negative MDA-MB-468 breast tumor cells. NgBR knockdown with siRNA abolishes estradiol-induced survivin expression in ER-positive T47D cells but not in ER-negative MDA-MB-468 cells. In addition, estradiol increases the expression of survivin and cell growth in ER-positive MCF-7 and T47D cells whereas knockdown of NgBR with siRNA reduces estradiol-induced survivin expression and cell growth. In summary, these results indicate that NgBR is a new molecular marker for breast cancer. The data suggest that the expression of NgBR may be essential in promoting ER-positive tumor cell proliferation via survivin induction

  8. Addition reaction of adamantylideneadamantane with Br2 and 2Br2: a computational study.

    Science.gov (United States)

    Islam, Shahidul M; Poirier, Raymond A

    2008-01-10

    Ab initio calculations were carried out for the reaction of adamantylideneadamantane (Ad=Ad) with Br2 and 2Br2. Geometries of the reactants, transition states, intermediates, and products were optimized at HF and B3LYP levels of theory using the 6-31G(d) basis set. Energies were also obtained using single point calculations at the MP2/6-31G(d)//HF/6-31G(d), MP2/6-31G(d)//B3LYP/6-31G(d), and B3LYP/6-31+G(d)//B3LYP/6-31G(d) levels of theory. Intrinsic reaction coordinate (IRC) calculations were performed to characterize the transition states on the potential energy surface. Only one pathway was found for the reaction of Ad=Ad with one Br2 producing a bromonium/bromide ion pair. Three mechanisms for the reaction of Ad=Ad with 2Br2 were found, leading to three different structural forms of the bromonium/Br3- ion pair. Activation energies, free energies, and enthalpies of activation along with the relative stability of products for each reaction pathway were calculated. The reaction of Ad=Ad with 2Br2 was strongly favored over the reaction with only one Br2. According to B3LYP/6-31G(d) and single point calculations at MP2, the most stable bromonium/Br3- ion pair would form spontaneously. The most stable of the three bromonium/Br3- ion pairs has a structure very similar to the observed X-ray structure. Free energies of activation and relative stabilities of reactants and products in CCl4 and CH2ClCH2Cl were also calculated with PCM using the united atom (UA0) cavity model and, in general, results similar to the gas phase were obtained. An optimized structure for the trans-1,2-dibromo product was also found at all levels of theory both in gas phase and in solution, but no transition state leading to the trans-1,2-dibromo product was obtained.

  9. Mechanistic aspects of the reaction between Br2 and chalcogenone donors (LE; E=S, Se): competitive formation of 10-E-3, T-shaped 1:1 molecular adducts, charge-transfer adducts, and [ (LE)2]2+ dications.

    Science.gov (United States)

    Aragoni, M C; Arca, M; Demartin, F; Devillanova, F A; Garau, A; Isaia, F; Lelj, F; Lippolis, V; Verani, G

    2001-07-16

    The synthesis and spectroscopic characterisation of the products obtained by treatment of N,N'-dimethylimidazolidine-2-thione (1), N,N'-dimethylimidazolidine-2-selone (2), N,N'-dimethylbenzoimidazole-2-thione (3) and N,N'-dimethylbenzoimidazole-2-selone (4) with Br2 in MeCN are reported, together with the crystal structures of the 10-E-3, T-shaped adducts 2 . Br2 (12), 3 . Br2 (13) and 4 . Br2 (14). A conductometric and spectrophotometric investigation into the reaction between 1-4 and Br2, carried out in MeCN, allows the equilibria involved in the formation of the isolated 10-E-3 (E = S, Se) hypervalent compounds to be hypothesised. In order to understand the reasons why S and Se donors can give different product types on treatment with Br2 and I2, DFT calculations have been carried out on 1-8, 19 and 20, and on their corresponding hypothetical [LEX]+ cations (L = organic framework; E = S, Se; X = Br, I), which are considered to be key intermediates in the formation of the different products. The results obtained in terms of NBO charge distribution on [LEX]+ species explain the different behaviour of 1-8, 19 and 20 in their reactions with Br2 and I2 fairly well. X-ray diffraction studies show 12-14 to have a T-shaped (10-E-3; E = S, Se) hypervalent chalcogen nature. They contain an almost linear Br-E-Br (E = S, Se) system roughly perpendicular to the average plane of the organic molecules. In 12, the Se atom of each adduct molecule has a short interaction with the Br(1) atom of an adjacent unit, such that the Se atom displays a roughly square planar coordination. The Se-Br distances are asymmetric [2.529(1) vs. 2.608(1) A], the shorter distance being that with the Br(1) atom involved in the short intermolecular contact. In contrast, in the molecular adducts 13 and 14, which lie on a two-fold crystallographic axis, the Br-E-Br system is symmetric and no short intermolecular interactions involving chalcogen and bromine atoms are observed. The adducts are arranged in

  10. Chalcogen- and halogen-bonds involving SX2 (X = F, Cl, and Br) with formaldehyde.

    Science.gov (United States)

    Mo, Lixin; Zeng, Yanli; Li, Xiaoyan; Zhang, Xueying; Meng, Lingpeng

    2016-07-01

    The capacity of SX2 (X = F, Cl, and Br) to engage in different kinds of noncovalent bonds was investigated by ab initio calculations. SCl2 (SBr2) has two σ-holes upon extension of Cl (Br)-S bonds, and two σ-holes upon extension of S-Cl (Br) bonds. SF2 contains only two σ-holes upon extension of the F-S bond. Consequently, SCl2 and SBr2 form chalcogen and halogen bonds with the electron donor H2CO while SF2 forms only a chalcogen bond, i.e., no F···O halogen bond was found in the SF2:H2CO complex. The S···O chalcogen bond between SF2 and H2CO is the strongest, while the strongest halogen bond is Br···O between SBr2 and H2CO. The nature of these two types of noncovalent interaction was probed by a variety of methods, including molecular electrostatic potentials, QTAIM, energy decomposition, and electron density shift maps. Termolecular complexes X2S···H2CO···SX'2 (X = F, Cl, Br, and X' = Cl, Br) were constructed to study the interplay between chalcogen bonds and halogen bonds. All these complexes contained S···O and Cl (Br)···O bonds, with longer intermolecular distances, smaller values of electron density, and more positive three-body interaction energies, indicating negative cooperativity between the chalcogen bond and the halogen bond. In addition, for all complexes studied, interactions involving chalcogen bonds were more favorable than those involving halogen bonds. Graphical Abstract Molecular electrostatic potential and contour map of the Laplacian of the electron density in Cl2S···H2CO···SCl2 complex.

  11. Synthesis and single crystal growth of perovskite semiconductor CsPbBr3

    Science.gov (United States)

    Zhang, Mingzhi; Zheng, Zhiping; Fu, Qiuyun; Chen, Zheng; He, Jianle; Zhang, Sen; Chen, Cheng; Luo, Wei

    2018-02-01

    As a typical representative of all-inorganic lead halide perovskites, cesium lead bromine (CsPbBr3) has attracted significant attention in recent years. The direct band gap semiconductor CsPbBr3 has a wide band gap of 2.25 eV and high average atomic number (Cs: 55, Pb: 82 and Br: 35), which meet most of the requirements for detection of X- and γ-ray radiation, such as high attenuation, high resistivity, and significant photoconductivity response. However, the growth of large volume CsPbBr3 single crystals remains a challenge. In this paper, the synthesis of CsPbBr3 polycrystalline powders by a chemical co-precipitation method was investigated and the optimum synthesis conditions were obtained. A large CsPbBr3 single crystal of 8 mm diameter and 60 mm length was obtained by a creative electronic dynamic gradient (EDG) method. X-ray diffraction (XRD) patterns and X-ray rocking curve showed that the CsPbBr3 crystal preferentially oriented in the (1 1 0) direction and had a low dislocation density and small residual stress in the crystal. The IR and UV-Vis transmittance and temperature-dependent photoluminescence (PL) spectra showed the crystal had a good basic optical performance. The almost linear current-voltage (I-V) curves implied good ohmic contact between the electrodes and crystal surfaces. The resistivity of the crystal was calculated 109-1010 Ω cm. The above results showed that the quality of the obtained crystal had met the demand of optoelectronic applications.

  12. Computations on the primary photoreaction of Br2 with CO2: stepwise vs concerted addition of Br atoms.

    Science.gov (United States)

    Xu, Kewei; Korter, Timothy M; Braiman, Mark S

    2015-04-09

    It was proposed previously that Br2-sensitized photolysis of liquid CO2 proceeds through a metastable primary photoproduct, CO2Br2. Possible mechanisms for such a photoreaction are explored here computationally. First, it is shown that the CO2Br radical is not stable in any geometry. This rules out a free-radical mechanism, for example, photochemical splitting of Br2 followed by stepwise addition of Br atoms to CO2-which in turn accounts for the lack of previously observed Br2+CO2 photochemistry in gas phases. A possible alternative mechanism in liquid phase is formation of a weakly bound CO2:Br2 complex, followed by concerted photoaddition of Br2. This hypothesis is suggested by the previously published spectroscopic detection of a binary CO2:Br2 complex in the supersonically cooled gas phase. We compute a global binding-energy minimum of -6.2 kJ mol(-1) for such complexes, in a linear geometry. Two additional local minima were computed for perpendicular (C2v) and nearly parallel asymmetric planar geometries, both with binding energies near -5.4 kJ mol(-1). In these two latter geometries, C-Br and O-Br bond distances are simultaneously in the range of 3.5-3.8 Å, that is, perhaps suitable for a concerted photoaddition under the temperature and pressure conditions where Br2 + CO2 photochemistry has been observed.

  13. LaBr3 spectrometry for environmental monitoring

    International Nuclear Information System (INIS)

    Toivonen, Harri; Vesterbacka, Kaj; Pelikan, Andreas

    2008-01-01

    Full text: In 2005-2007 Finland renewed its country-wide monitoring network of 260 stations. As a result of the process, the ambient dose rate is measured with Geiger counters and transferred in real time to the headquarters of the Radiation and Nuclear Safety Authority (STUK) and to regional Emergency Response Centres. When the renewal was initiated, the use of NaI spectrometers was considered. These, however, do not have energy resolution good enough for resolving I-131 (364 keV) from natural radiation (Pb-214 at 352 keV). It was envisaged that in future better detectors will emerge and therefore, the station infrastructure must support spectrometric measurements. Nowadays detectors based LaBr 3 are on the markets. The devices are compatible with standard nuclear electronics and they can be easily connected to a data acquisition system, such as a Linux-based computer at the monitoring stations of STUK. LaBr 3 detector has excellent properties for environmental monitoring. The detector is large enough (sensitivity) and it has good energy resolution (2.5 - 3 %) as compared with NaI (6 - 7 %). There are two major technical drawbacks which may prevent the usage of LaBr 3 detector for monitoring purposes. Firstly, the material contains impurities of La-138 and Ac-227 which give a nasty background. Secondly, the light output of the material varies as a function of temperature deteriorating the quality of the spectrum (broadening of peaks). The detector background can be measured accurately in a lead castle. Then, after live-time correction, this spectrum can be subtracted from the monitoring spectra without disturbing statistics essentially. However, absolute stability of the energy calibration is required. This was solved by fitting the La-138 contamination multiplet at 1436-1468 keV (gamma + X rays) using a novel algorithm which treats peaks as a family, not as individuals. The analysis provides peak shift in channel units. The software then adjusts the gain of the

  14. Long-wavelength limit of the static structure factors for mixtures of two simple molten salts with a common ion and generalized Bhatia-Thornton formalism: Molecular dynamics study of molten mixture Ag(Br0.7I0.3)

    International Nuclear Information System (INIS)

    Bitrian, Vicente; Trullas, Joaquim; Silbert, Moises

    2008-01-01

    The relation between thermodynamic properties and the long-wavelength limit of the structure factors for mixtures of two simple molten salts with a common ion is derived. While the long-wavelength limit of the partial structure factors for binary ionic systems is directly related to the isothermal compressibility, for ternary ionic systems it is shown that it is also related to the mean square thermal fluctuation in the relative concentration of the non-common ions. This result leads to a generalization of the Bhatia-Thornton formalism. From the local fluctuations in the total number-density, charge-density, and relative concentration, six static structure factors, and the corresponding spatial correlation functions, are defined. By introducing three complementary structure factors, it is possible to describe either these mixtures as a system of cations and anions irrespective of the species of the non-common ions, or solely the binary subsystem of the non-common ions. The generalized structure factors and their long-wavelength limits are illustrated by molecular dynamics simulation results of the molten mixture Ag(Br 0.7 I 0.3 ). The mixture retains the charge order characteristic of pure molten monovalent salts and the topological order observed in monovalent ionic melts in which the cations are smaller than the anions, while the main trends of the anionic chemical order are those of simple binary alloys. The long-wavelength fluctuations in the local relative concentration are found to be very sensitive to the choice of the short-range interactions between the non-common ions

  15. Long-wavelength limit of the static structure factors for mixtures of two simple molten salts with a common ion and generalized Bhatia-Thornton formalism: Molecular dynamics study of molten mixture Ag(Br{sub 0.7}I{sub 0.3})

    Energy Technology Data Exchange (ETDEWEB)

    Bitrian, Vicente [Departament de Fisica i Enginyeria Nuclear, Universitat Politecnica de Catalunya, Campus Nord UPC, Edifici B4-B5, Despatx B4-204, Jordi Girona 1-3, 08034 Barcelona (Spain); Trullas, Joaquim [Departament de Fisica i Enginyeria Nuclear, Universitat Politecnica de Catalunya, Campus Nord UPC, Edifici B4-B5, Despatx B4-204, Jordi Girona 1-3, 08034 Barcelona (Spain)], E-mail: quim.trullas@upc.edu; Silbert, Moises [School of Mathematics, University of East Anglia, Norwich NR4 7QF (United Kingdom)

    2008-12-15

    The relation between thermodynamic properties and the long-wavelength limit of the structure factors for mixtures of two simple molten salts with a common ion is derived. While the long-wavelength limit of the partial structure factors for binary ionic systems is directly related to the isothermal compressibility, for ternary ionic systems it is shown that it is also related to the mean square thermal fluctuation in the relative concentration of the non-common ions. This result leads to a generalization of the Bhatia-Thornton formalism. From the local fluctuations in the total number-density, charge-density, and relative concentration, six static structure factors, and the corresponding spatial correlation functions, are defined. By introducing three complementary structure factors, it is possible to describe either these mixtures as a system of cations and anions irrespective of the species of the non-common ions, or solely the binary subsystem of the non-common ions. The generalized structure factors and their long-wavelength limits are illustrated by molecular dynamics simulation results of the molten mixture Ag(Br{sub 0.7}I{sub 0.3}). The mixture retains the charge order characteristic of pure molten monovalent salts and the topological order observed in monovalent ionic melts in which the cations are smaller than the anions, while the main trends of the anionic chemical order are those of simple binary alloys. The long-wavelength fluctuations in the local relative concentration are found to be very sensitive to the choice of the short-range interactions between the non-common ions.

  16. CH3Br adsorption on MgO/Mo ultrathin films: A DFT study

    Science.gov (United States)

    Cipriano, Luis A.; Tosoni, Sergio; Pacchioni, Gianfranco

    2018-06-01

    The adsorption of methyl bromide on MgO ultrathin films supported on Mo(100) was studied by means of density functional theory calculations, in comparison to the MgO(100) and Mo(100) surfaces. The adsorption energy and geometry were shown to depend on the thickness of the supported oxide film. MgO films as thick as 2ML (or more) display adsorptive properties similar to MgO(100), i.e. the adsorption of CH3Br is mostly due to dispersion and the molecule lies in a tilted geometry almost parallel to the surface. The CH3Br HOMO-LUMO gap is almost unaltered with respect to the gas phase. On metallic Mo(100) surfaces the bonding is completely different with the CH3Br molecule strongly bound and the C-Br bond axis almost vertical with respect to the metal surface. The MgO monolayer supported on Mo exhibits somehow intermediate properties: the tilt angle is larger and the bonding is stronger than on MgO(100), due to the effect of the supporting metal. In this case, a small reduction of the HOMO-LUMO gap of the adsorbed molecule is reported. The results help to rationalize the observed behavior in photodissociation of CH3Br supported on different substrates.

  17. CsPbBr{sub 3} nanocrystal saturable absorber for mode-locking ytterbium fiber laser

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yan; Li, Yue; Xu, Jianqiu; Tang, Yulong, E-mail: yulong@sjtu.edu.cn [Key Laboratory for Laser Plasmas (MOE), Department of Physics and Astronomy, Collaborative Innovation Center of IFSA, Shanghai Jiao Tong University, Shanghai 200240 (China); Hu, Zhiping; Tang, Xiaosheng [Key Laboratory of Optoelectronic Technology and Systems of the Education Ministry of China, College of Optoelectronic Engineering, Chongqing University, Chongqing 400044 (China)

    2016-06-27

    Cesium lead halide perovskite nanocrystals (CsPbX{sub 3}, X = Cl, Br, I) have been reported as efficient light-harvesting and light-emitting semiconductor materials, but their nonlinear optical properties have been seldom touched upon. In this paper, we prepare layered CsPbBr{sub 3} nanocrystal films and characterize their physical properties. Broadband linear absorption from ∼0.8 to over 2.2 μm and nonlinear optical absorption at the 1-μm wavelength region are measured. The CsPbBr{sub 3} saturable absorber (SA), manufactured by drop-casting of colloidal CsPbBr{sub 3} liquid solution on a gold mirror, shows modulation depth and saturation intensity of 13.1% and 10.7 MW/cm{sup 2}, respectively. With this SA, mode-locking operation of a polarization-maintained ytterbium fiber laser produces single pulses with duration of ∼216 ps, maximum average output power of 10.5 mW, and the laser spectrum is centered at ∼1076 nm. This work shows that CsPbBr{sub 3} films can be efficient SA candidates for fiber lasers and also have great potential to become broadband linear and nonlinear optical materials for photonics and optoelectronics.

  18. CsPbBr3 nanocrystal saturable absorber for mode-locking ytterbium fiber laser

    Science.gov (United States)

    Zhou, Yan; Hu, Zhiping; Li, Yue; Xu, Jianqiu; Tang, Xiaosheng; Tang, Yulong

    2016-06-01

    Cesium lead halide perovskite nanocrystals (CsPbX3, X = Cl, Br, I) have been reported as efficient light-harvesting and light-emitting semiconductor materials, but their nonlinear optical properties have been seldom touched upon. In this paper, we prepare layered CsPbBr3 nanocrystal films and characterize their physical properties. Broadband linear absorption from ˜0.8 to over 2.2 μm and nonlinear optical absorption at the 1-μm wavelength region are measured. The CsPbBr3 saturable absorber (SA), manufactured by drop-casting of colloidal CsPbBr3 liquid solution on a gold mirror, shows modulation depth and saturation intensity of 13.1% and 10.7 MW/cm2, respectively. With this SA, mode-locking operation of a polarization-maintained ytterbium fiber laser produces single pulses with duration of ˜216 ps, maximum average output power of 10.5 mW, and the laser spectrum is centered at ˜1076 nm. This work shows that CsPbBr3 films can be efficient SA candidates for fiber lasers and also have great potential to become broadband linear and nonlinear optical materials for photonics and optoelectronics.

  19. UV-Induced Anisotropy In CdBr2-CdBr2: Cu Nanostructures

    Directory of Open Access Journals (Sweden)

    El-Naggar A. M.

    2015-09-01

    Full Text Available We have found an occurrence of anisotropy in the nanostructure CdBr2-CdBr2: Cu nanocrystalline films. The film thickness was varied from 4 nm up to 80 nm. The films were prepared by successive deposition of the novel layers onto the basic nanocrystals. The detection of anisotropy was performed by occurrence of anisotropy in the polarized light at 633 nm He-Ne laser wavelength. The occurrence of anisotropy was substantially dependent on the film thickness and the photoinduced power density. Possible mechanisms of the observed phenomena are discussed.

  20. Revised and extended analysis of Br IV

    Science.gov (United States)

    Riyaz, A.; Rahimullah, K.; Tauheed, A.

    2014-01-01

    The spectrum of three-times ionized bromine Br IV has been studied in the 319-2350 Å wavelength region. The spectrum was recorded on a 3-m normal incidence vacuum spectrograph at the St. Francis Xavier University, Antigonish (Canada) and 6.65-m grazing incidence spectrograph at the Zeeman laboratory (Amsterdam). The light sources used were a triggered spark and sliding spark, respectively. The ground configuration of Br IV 3d104s24p2, the excited configurations 3d104s4p3+3d104s24p (4d+5d+6d+5s+6s+7s) in the odd parity system and 3d104s24p (5p+4f+5f)+3d104s4p2 (4d+5s)+3d104p4 in the even parity system have been studied. Relativistic Hartree-Fock (HFR) and least squares fitted (LSF) parametric calculations were used to interpret the observed spectrum. 120 Levels of Br IV have now been established, 58 being new. Among 424 spectral lines, 277 are newly classified. The levels 4s4p35S2, 4s24p4d 3F4 and 4p5p (3P0, 1, 3D1, 2, 3S1) are revised. We estimate the accuracy of our measured wavelength for sharp and unblended lines to be ±0.005 Å. The ionization limit is determined as 385,390±100 cm-1 (47.782±0.012 eV).

  1. Dicty_cDB: FC-BR23 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available FC (Link to library) FC-BR23 (Link to dictyBase) - - - Contig-U15008-1 FC-BR23Z (Li...nk to Original site) - - FC-BR23Z 641 - - - - Show FC-BR23 Library FC (Link to library) Clone ID FC-BR23 (Li.../dictycdb.biol.tsukuba.ac.jp/CSM/FC/FC-BR/FC-BR23Q.Seq.d/ Representative seq. ID FC-BR2...3Z (Link to Original site) Representative DNA sequence >FC-BR23 (FC-BR23Q) /CSM/FC/FC-BR/FC-BR23Q.Seq....9 0.0 SLA211 (SLA211Q) /CSM/SL/SLA2-A/SLA211Q.Seq.d/ 1029 0.0 FC-BR23 (FC-BR23Q) /CSM/FC/FC-BR/FC-BR2

  2. Operation of the BR2 Reactor

    International Nuclear Information System (INIS)

    Gubel, P.

    2006-01-01

    The BR2 is still SCK-CEN's most important nuclear facility. After an extensive refurbishment of 22 months to compensate for the ageing of the installations, to enhance the reliability of operation and to comply with modern safety standards, it was restarted in April 1997. The facility is mainly used for the irradiation and testing of fuels and materials and for commercial productions - including radioisotopes for the medical and industrial uses, and NTD-Silicon. The article describes the main achievements and activities in 2005

  3. BR2 Reactor: Irradiation of fuels

    International Nuclear Information System (INIS)

    Verwimp, A.

    2005-01-01

    Safe, reliable and economical operation of reactor fuels, both UO 2 and MOX types, requires in-pile testing and qualification up to high target burn-up levels. In-pile testing of advanced fuels for improved performance is also mandatory. The objectives of research performed at SCK-CEN are to perform Neutron irradiation of LWR (Light Water Reactor) fuels in the BR2 reactor under relevant operating and monitoring conditions, as specified by the experimenter's requirements and to improve the on-line measurements on the fuel rods themselves

  4. Operation of the BR2 Reactor

    International Nuclear Information System (INIS)

    Gubel, P.

    2005-01-01

    The BR2 is still SCK-CEN's most important nuclear facility. After an extensive refurbishment of 22 months to compensate for the ageing of the installations, to enhance the reliability of operation and to comply with modern safety standards, it was restarted in April 1997. The facility is mainly used for the irradiation and testing of fuels and materials and for commercial productions - including radioisotopes for the medical and industrial uses, and NTD-Silicon. The article describes the main activities and achievements in 2004

  5. Positron emission tomography of experimental melanoma with [{sup 76}Br]5-bromo-2-thiouracil

    Energy Technology Data Exchange (ETDEWEB)

    Maars, Ulla E-mail: Ulla.Mars@tox.uu.se; Tolmachev, Vladimir; Sundin, Anders

    2000-11-01

    Positron emission tomography (PET) has evolved as a new diagnostic modality in cancer patients. Thioureylenes, such as thiouracil and methimazole, are known to be incorporated into growing melanin and selectively retained in melanotic melanoma. In the present study we used [{sup 76}Br]5-bromo-2-thiouracil as tracer for PET imaging of human and murine melanotic melanoma transplanted subcutaneously into rats. The melanomas were clearly depicted 1 day after the injection, when [{sup 76}Br]5-bromo-2-thiouracil was retained in the tumors though the overall radioactivity concentration in the body had declined. Accumulation of {sup 76}Br was also seen in bladder, liver, and kidney. In addition, the rats were simultaneously injected with [{sup 125}I]5-iodo-2-thiouracil and the tissue distribution of radioactivity was mapped by whole-body autoradiography. The results confirmed the selective uptake of thiouracil in the melanoma where the concentration of {sup 125}I-radioactivity was about three-fold higher than that in the liver and lungs. These results show the possibility of using [{sup 76}Br]5-bromo-2-thiouracil for PET diagnostics of melanoma, including dosimetry, prior to targeted therapy using [{sup 131}I]5-iodo-2-thiouracil or [{sup 211}At]5-astato-2-thiouracil.

  6. Estimering af brændstofforbrug vha. GPS Data

    DEFF Research Database (Denmark)

    Andersen, Ove; Lahrmann, Harry; Torp, Kristian

    2010-01-01

    Det er simpelt og billigt at opsamle GPS målinger fra køretøjer. Når større mængder GPS data indsamles fra et passende antal køretøjer kan dataen bruges til at beregne f.eks. køretider. Det er ligeledes muligt ud fra GPS data at estimere miljøindikatorer så som, hvor aggressivt kører bilister og er...... der nogle vejstrækninger, der har en højere (negativ) miljø påvirkning end andre? I denne artikel præsenterer et forsøg, hvor GPS data anvendes til at estimere brændstofforbruget ved en enkelt tur og for vejnettet generelt. Dette gøres ved at opbygge en database med GPS data. Ud fra disse data gives...

  7. Enhanced photovoltaic performance of CH3NH3PbBrXI3-X-based perovskite solar cells via anti-solvent extraction

    Science.gov (United States)

    Jiang, Zhaoyi; Zhang, Weijia; Lu, Chaoqun; Ma, Denghao; Liu, Haixu; Yu, Wei; Zhang, Yu; Ma, Qiang; Zhang, Yulong

    2018-06-01

    In this paper, the two-step sequential deposition method was used to prepare the CH3NH3PbBrXI3-X films by introducing CH3NH3Br in the precursors. The surface morphology of the PbI2 films was controlled by anti-solvent extraction (ASE) to improve the microstructure and photo-physical properties of the perovskite films. It was noteworthy that, compared to the compact PbI2 films, the porous PbI2 films facilitated the growth of crystals and bromine incorporation in films, and the prepared perovskite films exhibited enlarged grain size, increased light absorption, enhanced Br incorporation and prolonged carrier lifetime, which resulted in excellent photo-electrical properties of the CH3NH3PbBrXI3-X films. With porous PbI2 templates, the inverted planar perovskite solar cells based on films with appropriate Br incorporation (CH3NH3Br/CH3NH3I mole ratio = 3/7) showed a photovoltaic conversion efficiency (PCE) of 14.9%, and the stability of the devices in air was elevated. Consequently, the high-quality CH3NH3PbBrXI3-X films can be obtained with porous PbI2 templates for improving the performance of the perovskite solar cells.

  8. Dye adsorbates BrPDI, BrGly, and BrAsp on anatase TiO2(001) for dye-sensitized solar cell applications

    Science.gov (United States)

    Çakır, D.; Gülseren, O.; Mete, E.; Ellialtıoǧlu, Ş.

    2009-07-01

    Using the first-principles plane-wave pseudopotential method within density functional theory, we systematically investigated the interaction of perylenediimide (PDI)-based dye compounds (BrPDI, BrGly, and BrAsp) with both unreconstructed (UR) and reconstructed (RC) anatase TiO2(001) surfaces. All dye molecules form strong chemical bonds with surface in the most favorable adsorption structures. In UR-BrGly, RC-BrGly, and RC-BrAsp cases, we have observed that highest occupied molecular orbital and lowest unoccupied molecular orbital levels of molecules appear within band gap and conduction-band region, respectively. Moreover, we have obtained a gap narrowing upon adsorption of BrPDI on the RC surface. Because of the reduction in effective band gap of surface-dye system and possibly achieving the visible-light activity, these results are valuable for photovoltaic and photocatalytic applications. We have also considered the effects of hydration of surface to the binding of BrPDI. It has been found that the binding energy drops significantly for the completely hydrated surfaces.

  9. Ecotoxicity of glyphosate and aterbane® br surfactant on guaru (Phalloceros caudimaculatus) = Ecotoxicologia do glifosato e surfactante aterbane® br para guaru (Phalloceros caudimaculatus)

    OpenAIRE

    Natália Sayuri Shiogiri; Silvia Patrícia Carraschi; Patrícia Cubo; Bárbara Lopes Schiavetti; Claudinei da Cruz; Robinson Antonio Pitelli

    2010-01-01

    Aquatic macrophytes are important components of aquatic ecosystems, but these plants have become a problem due to their occurrence in different regions. Some studies aimed to demonstrate the effectiveness of herbicides to control these macrophytes; however, fewstudies report the possible ecotoxicological effects. The objective of this study was to estimate the acute toxicity (LC (I)50;96h) and assess water quality variables for glyphosate in the Rodeo® formulation, Aterbane® BR surfactant and...

  10. Investigations on the system Te/O/Br

    International Nuclear Information System (INIS)

    Oppermann, H.; Kunze, G.; Wolf, E.; Titov, V.A.; Kokovin, G.A.

    1978-01-01

    The melting point diagram of the system TeBr 4 -TeO 2 was obtained by total pressure measurements and DTA measurements. A congruent melting composition Te 6 O 11 Br 2 exists, the melting point is 570 0 C. The enthalpy of formation and the standard entropy of the species TeOBr 2 ,g was derived from measurements of the total pressure over Te 6 O 11 Br 2 /TeBr 4 and from the transport behaviour of the TeO 2 with Br 2 . From the decomposition-pressure measurements over Te 6 O 11 Br 2 /TeO 2 follow the partial pressures. The enthalpy of formation ΔH 0 (Te 6 O 11 Br 2 ,f,298) -453.5 kcal/Mol was obtained from the enthalpy of solution. The transport-behaviour of TeO 2 with HBr, TeBr 4 and Br 2 and that of Te 6 O 11 Br 2 is clear with the thermodynamic data of TeOBr 2 . (author)

  11. Origin of halides (Cl- and Br-) and of their stable isotopes (d37Cl and d81Br) at the Tournemire URL (France) - Experimental and numerical approach

    Science.gov (United States)

    Bachir-Bey, Nassim; Matray, Jean-Michel

    2014-05-01

    This work is part of research conducted by the Institute of Radiological and Nuclear Safety (IRSN) on the geological disposal of High-Level and Intermediate-Level Long-Lived (HL-ILLL) radioactive waste in deep clayrocks. In France, the choice of the potential host rock for the geological storage is focused on the Callovian-Oxfordian (COx) of Meuse/Haute-Marne from its low permeability, capacity for self- sealing, high sorption and ability to radionuclide (RN) transport by diffusion. IRSN, which plays an expert role for ASN has its own underground research laboratory in a clayrock which has strong analogies to the COx. This is the Toarcian/Domerian clayrock located at Tournemire in southern Aveyron in France. The purpose of this study was to assess the transfer of RN in the Tournemire clayrock through the study of halides contents and of their stable isotopes (Cl-, Br-, Cl-/Br-, d37Cl, d81Br). The approach used was multiple and consisted for halides to: 1) Assess their stock in different fractions of the rock by applying several techniques including i) alkaline fusion for their total stock, ii) leaching to access their stock in porewater and to mineral phases sensitive to dissolution iii) cubic diffusion for their stock in porewater, 2) Get their diffusive transport parameters of a selection of samples from the upper Toarcian by cubic diffusion experiments modelled using the Hytec transport code developed by Mines ParisTech and 3) Model their transport after palaeohydrogeological known changes of the Tournemire massif. The experimental approach, conducted at the LAME lab, did not lead to an operational protocol for the alkaline fusion due to an incomplete rock dissolution. Leaching was used to characterize the concentrations of halides in the fractions of pore water and of minerals sensitive to dissolution. The results show levels of halides much higher than those of pore water with very low Cl/Br ratios likely resulting from the dissolution of mineral species. The

  12. I pionieri italiaNi della geofisiCa

    Directory of Open Access Journals (Sweden)

    P. CALOI

    1964-06-01

    Full Text Available Vengono rapidamente passati in rassenga, seguendo<br />l'ordine cronologico, gli studiosi di geofisica — intesa in senso lato — clie,<br />a partire dalla seconda meta del Settecento, ebbero ad interessarsi in Italia<br />di elettricita atmosferica, magnetismo terrestre, idrografla, oceanografia fisica,<br />sismologia e vulcanologia, con intenti pionieristici. Sono ricordati i principali<br />risultati raggiunti da una trentina di ricercatori fra i quali spiccano, per la<br />vastita del lavoro compiuto e per la novita dei risultati, Leopoldo Nobili e Macedonio<br />Melloni. Ma, ciascuno nei suo campo, scoperte di rilievo fecero pure<br />G. B. Beccaria, Luigi Palmieri, Carlo Matteucci, Timoteo Bertelli, Luigi De<br />Marcbi, Carlo Somigliana, Emilio Oddone, Alfonso Sella e Domenico Pacini.<br />Alcuni vantano priorita di rilievo: scoperta della doppia oscillazione diurna<br />del barometro (Chiminello, 1780; unicita sorgiva delle varie radiazioni dello<br />spettro (M. Melloni; sismografo elettromagnetico a registrazione continua<br />(Palmieri, 1855; microsismi (Bertelli, 1872; il paleomagnetismo (Oddone e<br />Sella, 1891; la radiazione cosmica (Pacini, 1910; . ..

  13. <i>Laserpitium> gr. <i>nestleri> (Umbelliferae

    Directory of Open Access Journals (Sweden)

    Montserrat, Pedro

    2003-12-01

    Full Text Available For the revision of the genus <i>Laserpitium> for Flora lberica I have revised numerous materials of many herbaria. In this paper I present! the result of a morphological and taxonomic study of <i>L. nestlerii> and <i>L. eliasiii>, supported with numerous iIIustrations only partially included here. <i>L. nestlerii> subsp. <i>nestleri> is distributed from Central France (Central Massif to the SE of the lberian Peninsula. Two new subspecies allow to relate the morphological variability observed with their geographical distribution. <i>L. nestlerii> subsp. <i>flabellatum> is found in the Pyrenees and Ihe Cantabrian mountains, and <i>L. nestlerii> subsp. <i>lainzii> is a remarkable endemism located in the mountains of the N of Leon. <i>L. eliasiii> also presents a great morphological variability. Their distribution area is overlapped partially with that of <i>L. nestlerii> subsp. <i>flabellatum>. <i>L. eliasiii> subsp. <i>ordunae> include forms located in the Basque country while the most western populations, from W Galicia and N of Portugal, belong to <i>L. eliasiii> subsp. <i>thalictrifolium>. I propose different new varieties to highlight some remarkable local forms. The study of mericarp section. the distribution of estomate and the morphology of hairs and basal leaves are very useful for delimitate these taxa.<br>>Con motivo de la revisión del género <i>Laserpitium> para Flora Ibérica he revisado mucho material de distintos herbarios. En este trabajo presento el resultado de un estudio morfológico y taxonómico de las especies <i>L. nestlerii> y <i>L. eliasiii>, apoyado en numerosas ilustraciones. de las cuales sólo una pequeña parte se incluyen en este artículo. <i>L. nestlerii> subsp. <i>nestleri> se distribuye desde el Centro de Francia (Massif Central hasta el SE de la Península Ibérica. Dos nuevas subespecies permiten relacionar la variabilidad morfológica observada con su

  14. Observation of Enhanced Hole Extraction in Br Concentration Gradient Perovskite Materials.

    Science.gov (United States)

    Kim, Min-Cheol; Kim, Byeong Jo; Son, Dae-Yong; Park, Nam-Gyu; Jung, Hyun Suk; Choi, Mansoo

    2016-09-14

    Enhancing hole extraction inside the perovskite layer is the key factor for boosting photovoltaic performance. Realization of halide concentration gradient perovskite materials has been expected to exhibit rapid hole extraction due to the precise bandgap tuning. Moreover, a formation of Br-rich region on the tri-iodide perovskite layer is expected to enhance moisture stability without a loss of current density. However, conventional synthetic techniques of perovskite materials such as the solution process have not achieved the realization of halide concentration gradient perovskite materials. In this report, we demonstrate the fabrication of Br concentration gradient mixed halide perovskite materials using a novel and facile halide conversion method based on vaporized hydrobromic acid. Accelerated hole extraction and enhanced lifetime due to Br gradient was verified by observing photoluminescence properties. Through the combination of secondary ion mass spectroscopy and transmission electron microscopy with energy-dispersive X-ray spectroscopy analysis, the diffusion behavior of Br ions in perovskite materials was investigated. The Br-gradient was found to be eventually converted into a homogeneous mixed halide layer after undergoing an intermixing process. Br-substituted perovskite solar cells exhibited a power conversion efficiency of 18.94% due to an increase in open circuit voltage from 1.08 to 1.11 V and an advance in fill-factor from 0.71 to 0.74. Long-term stability was also dramatically enhanced after the conversion process, i.e., the power conversion efficiency of the post-treated device has remained over 97% of the initial value under high humid conditions (40-90%) without any encapsulation for 4 weeks.

  15. Bandgap engineering of lead-free double perovskite Cs_2AgBiBr_6 through trivalent metal alloying

    International Nuclear Information System (INIS)

    Du, Ke-zhao; Mitzi, David B.; Meng, Weiwei; Wang, Xiaoming; Yan, Yanfa

    2017-01-01

    The double perovskite family, A_2M"IM"I"I"IX_6, is a promising route to overcome the lead toxicity issue confronting the current photovoltaic (PV) standout, CH_3NH_3PbI_3. Given the generally large indirect band gap within most known double perovskites, band-gap engineering provides an important approach for targeting outstanding PV performance within this family. Using Cs_2AgBiBr_6 as host, band-gap engineering through alloying of In"I"I"I/Sb"I"I"I has been demonstrated in the current work. Cs_2Ag(Bi_1_-_xM_x)Br_6 (M=In, Sb) accommodates up to 75 % In"I"I"I with increased band gap, and up to 37.5 % Sb"I"I"I with reduced band gap; that is, enabling ca. 0.41 eV band gap modulation through introduction of the two metals, with smallest value of 1.86 eV for Cs_2Ag(Bi_0_._6_2_5Sb_0_._3_7_5)Br_6. Band structure calculations indicate that opposite band gap shift directions associated with Sb/In substitution arise from different atomic configurations for these atoms. Associated photoluminescence and environmental stability of the three-metal systems are also assessed. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. High energy XeBr electric discharge laser

    Science.gov (United States)

    Sze, Robert C.; Scott, Peter B.

    1981-01-01

    A high energy XeBr laser for producing coherent radiation at 282 nm. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr is used as the halogen donor which undergoes harpooning reactions with Xe.sub.M * to form XeBr*.

  17. Free-tropospheric BrO investigations based on GOME

    Science.gov (United States)

    Post, P.; van Roozendael, M.; Backman, L.; Damski, J.; Thölix, L.; Fayt, C.; Taalas, P.

    2003-04-01

    Bromine compounds contribute significantly to the stratospheric ozone depletion. However measurements of most bromine compounds are sparse or non-existent, and experimental studies essentially rely on BrO observations. The differences between balloon and ground based measurements of stratospheric BrO columns and satellite total column measurements are too large to be explained by measurement uncertainties. Therefore, it has been assumed that there is a concentration of BrO in the free troposphere of about 1-3 ppt. In a previous work, we have calculated the tropospheric BrO abundance as the difference between total BrO and stratospheric BrO columns. The total vertical column densities of BrO are extracted from GOME measurements using IASB-BIRA algorithms. The stratospheric amount has been calculated using chemical transport models (CTM). Results from SLIMCAT and FinROSE simulations are used for this purpose. SLIMCAT is a widely used 3D CTM that has been tested against balloon measurements. FinROSE is a 3D CTM developed at FMI. We have tried several different tropospheric BrO profiles. Our results show that a profile with high BrO concentrations in the boundary layer usually gives unrealistically high tropospheric column values over areas of low albedo (like oceans). This suggests that the tropospheric BrO would be predominantly distributed in the free troposphere. In this work, attempts are made to identify the signature of a free tropospheric BrO content when comparing cloudy and non-cloudy scenes. The possible impact of orography on measured BrO columns is also investigated.

  18. Brüssel Euroopa pealinnaks? / Ülar Mark

    Index Scriptorium Estoniae

    Mark, Ülar, 1968-

    2009-01-01

    Brüsseli Euroopa kvartali planeerimisvõistlusest, mille peakorraldaja oli Brüsseli pealinna piirkond koos Brüsseli linna ja Euroopa Komisjoniga. Eestist osales žüriis arhitekt Ülar Mark. Meeskonna Atelier Christian de Portzamparc võidutööst ja teiste teise vooru pääsenud nelja meeskonna (JDS / Julien De Smedt Architects, OMA / Office for Metropolitan Architecture, Xaveer De Geyter Architect, Fletcher Priest Architects) töödest

  19. BrO measurements over the Eastern North-Atlantic

    Directory of Open Access Journals (Sweden)

    U. Platt

    2009-12-01

    Full Text Available The aim of the work presented here was to detect BrO in the marine boundary layer over the Eastern North-Atlantic by Multi AXis-Differential Optical Absorption Spectroscopy (MAX-DOAS of scattered sunlight. With this technique, information about the concentration and the vertical profile of trace gases in the atmosphere can be gained. BrO can be formed in the marine atmosphere by degradation of biogenic organohalogens or by oxidation of bromide in sea salt aerosol. BrO influences the chemistry in marine air in many ways, e.g. since it catalytically destroys ozone, changes the NO2/NO-ratio as well as the OH/HO2-ratio and oxidises DMS. However, the abundance and the significance of BrO in the marine atmosphere is not yet fully understood. <br>> We report on data collected during a ship cruise, which took place along the West African Coast in February 2007, within the framework of the Surface Ocean PRocesses in the ANthropocene project (SOPRAN. Tropospheric BrO could be detected during this cruise at peak mixing ratios of (10.2±3.7 ppt at an assumed layer height of 1 km on 18 February 2007. Furthermore, it was found that the mean BrO concentrations increased when cruising close to the African Coast suggesting that at least part of the BrO might have originated from there.

  20. MTR fuel testing in BR2

    International Nuclear Information System (INIS)

    Jacquet, P.; Verwimp, A.; Wirix, S.

    2000-01-01

    New fuel design for MTR 's requires to be qualified under representative conditions, that is geometry, neutron spectrum, heat flux and thermo hydraulic conditions. An irradiation device for fuel plates has been designed to derive the maximum benefit from the BR2 irradiation capacities. The fuel plates can be easily extracted from their support during a shutdown to undergo additional tests. One of these tests is the measurement of the thickness changes along the fuel plate. To that purpose, a facility in the reactor water pool has been designed to measure the fuel swelling with an accuracy of 5 μm using inductive probes. At SCK-CEN, the full range of destructive and non-destructive PIE can be performed, including γ-scanning, wet sipping, surface examination and other methods. (author)

  1. Predecommissioning radiological survey of BR3 infrastructures

    International Nuclear Information System (INIS)

    Cantrel, E.

    2006-01-01

    The decommissioning of the BR3 (Belgian Reactor 3) approaches its final phase, in which the buildings infrastructures are being decontaminated targeting either the reuse or the conventional demolition after denuclearisation. In a PWR with a significant operation lifetime, such as the BR3, maintenance operations, failure and/or leakages, incidents occurring in the different circuits of the plant result in the contamination of the buildings infrastructures at various activity levels with contaminants penetrating/migrating up to several cm inside the material bulk structure. Moreover, the BR3 bioshield has been exposed to rather high neutron leakage fluxes during the reactor operation and is therefore activated. The different radiological situations faced require the implementation of different characterization methodologies based on the use of an adequate combination of measurement devices and/or sampling devices. The non-destructive assay of activation depth using the ISOCS (In Situ Object Counting System) and a specific spectra analysis protocol has been tested in 2004. The first results obtained were encouraging and the qualification program for activated material is running. We are now investigating the possibilities to extend the methodology to building materials contaminated in-depth with 137 Cs. The overall process of dismantling/denuclearization of the BR3 building infrastructure consists of: (1) a preliminary characterization and determination of the contamination or activation depth; (2) the determination of the decontamination method; (3) the effective decontamination and clean up; (4) a possible intermediate characterization followed by an additional decontamination step; and (5) the characterization for clearance. The more accurate the preliminary survey is performed the less additional control/decontamination cycles are needed to reach clearance levels. The pre-decommissioning characterization process includes a preliminary categorisation (see picture

  2. BR-100 spent fuel shipping cask development

    International Nuclear Information System (INIS)

    McGuinn, E.J.; Childress, P.C.

    1990-01-01

    Continued public acceptance of commercial nuclear power is contingent to a large degree on the US Department of Energy (DOE) establishing an integrated waste management system for spent nuclear fuel. As part of the from-reactor transportation segment of this system, the B ampersand W Fuel Company (BWFC) is under contract to the DOE to develop a spent-fuel cask that is compatible with both rail and barge modes of transportation. Innovative design approaches were the keys to achieving a cask design that maximizes payload capacity and cask performance. The result is the BR-100, a 100-ton rail/barge cask with a capacity of 21 PWR or 52 BWR ten-year cooled, intact fuel assemblies. 3 figs

  3. In situ Spectroscopy of Solid-State Chemical Reaction in PbBr2-Deposited CsBr Crystals

    Science.gov (United States)

    Kondo, Shin-ichi; Matsunaga, Toshihiro; Saito, Tadaaki; Asada, Hiroshi

    2003-09-01

    It is possible to measure the fundamental optical absorption spectra of CsPbBr3 and Cs4PbBr6, whose stability is predicted by the study of phase diagram in the binary system CsBr-PbBr2, by means of in situ optical absorption and reflection spectroscopy of thermally induced solid-state chemical reaction in PbBr2-deposited CsBr crystals. On heavy annealing of the crystals, the Pb2+ ions are uniformly dispersed in the crystal matrix. The present experiment provides a novel method for measuring intrinsic optical absorption of ternary metal halides and also for in situ monitoring of doping metal halide crystal with impurities (metal ions or halogen ions).

  4. Photoresponse of CsPbBr3 and Cs4PbBr6 Perovskite Single Crystals.

    Science.gov (United States)

    Cha, Ji-Hyun; Han, Jae Hoon; Yin, Wenping; Park, Cheolwoo; Park, Yongmin; Ahn, Tae Kyu; Cho, Jeong Ho; Jung, Duk-Young

    2017-02-02

    High-quality and millimeter-sized perovskite single crystals of CsPbBr 3 and Cs 4 PbBr 6 were prepared in organic solvents and studied for correlation between photocurrent generation and photoluminescence (PL) emission. The CsPbBr 3 crystals, which have a 3D perovskite structure, showed a highly sensitive photoresponse and poor PL signal. In contrast, Cs 4 PbBr 6 crystals, which have a 0D perovskite structure, exhibited more than 1 order of magnitude higher PL intensity than CsPbBr 3 , which generated an ultralow photoresponse under illumination. Their contrasting optoelectrical characteristics were attributed to different exciton binding energies, induced by coordination geometry of the [PbBr 6 ] 4- octahedron sublattices. This work correlated the local structures of lead in the primitive perovskite and its derivatives to PL spectra as well as photoconductivity.

  5. Preambolo al Catalogo Sismico Nazionale (CSN. I criteri di informazione del Catalogo Sismico Nazionale (CSN

    Directory of Open Access Journals (Sweden)

    M. VECCHI

    1979-06-01

    Full Text Available

    This note presents a study meant to set out a national catalogue<br />(C.S.N. of seismic events the epicentres of which are to be found in<br />Italian territory (or nearby. The catalogue, that will start from the<br />year 1450 B.C., could be used for various purpose employing modern<br />technologies.<br />The complete C.S.N, is made of three main parts, each of which can<br />also have a separate life:<br />1 An Analytical Catalogue which comprises the greater part of<br />data and is the most complete;<br />2 A Macroseismic Atlas that shows the macroseismic aspect of<br />the most relevant events;<br />3 A Macroseismic Catalogue that translates in numeric terms the<br />Atlas.

    To these is added a comprehensive Bibliography subdivided into 24<br />chapters each of which covers one of the 24 time periods into which the<br />catalogue has been subdivided.<br />The Analytical Catalogue besides giving the main parameters for each<br />earthquake (date, epicentre, hypocentral depth, MCS scale intensity, raagnitudo,<br />each with its own reliability index gives indications also on the<br />following sideline data:<br />1 epicentral location (meaning by this the geographic region and<br />the eventual indication that the epicentre is to be found on a borderline<br />touching more geographic regions, or in the sea, or on the coast, or othermise<br />in the external band (see text;<br />2 with a reference to the Atlas, the event is shown as having been<br />dealt with also mocroseismic data and it will con be found, as such, in<br />the Atlas and in the Macroseismic Catalogue;<br />3 indications on the typology of the earthquake: i.e. whether it is an<br />« isolated » earthquake, or a « seismic period » (and if so with the indication<br />of the foreshock, main or aftershocks or of a swarm;<br />4 the possibility of indicating up to 7 sets of information suitably<br />chose among 40 additional notes regarding instrumental, geophysical,<br

  6. On the electrodeposition of /sup 80m/Br, /sup 80/Br and /sup 82/Br species from (eta, gamma) activated dibromoethane - N,N-dimethyl aniline mixture

    International Nuclear Information System (INIS)

    Zaman, M.R.

    1997-01-01

    Thermal neutron activation have been carried out in dibromomethane (DBM)-n,n-dimethyl aniline (N,N-DMA) system and the /sup 80m/Br, /sup 82/Br species have been electrodeposited on Ag/AgBr electrodes under a constant electric field of 175 volts cm/sup -1/. With the addition of N,N-DMA, anodic deposition has been severely decreased for all the radiobromines and cathode plate shows zero activities. Results are critically discussed by explaining the chemical reactivity of the amine. Electrode deposition pattern and the chemical stabilization mode of the nucleogenic bromine species in this system are deduced to some extents. (author)

  7. Elimination of nonspecific radioactivity from [{sup 76}Br]bromide in PET study with [{sup 76}Br]bromodeoxyuridine

    Energy Technology Data Exchange (ETDEWEB)

    Li Lu; Bergstroem, Mats E-mail: Mats.Bergstroem@pet.uu.se; Fasth, Karl-Johan; Wu Feng; Eriksson, Barbro; Laangstroem, Bengt

    1999-10-01

    [{sup 76}Br]Bromodeoxyuridine ([{sup 76}Br]BrdU) might allow a determination of proliferation in vivo using positron emission tomography (PET), but only with consideration of organ nonspecific radioactivity constituted by [{sup 76}Br]bromide. A first study assessed the potential of diuretics to eliminate [{sup 76}Br]bromide. [{sup 76}Br]Bromide was injected in the vein of rats and different diuretic combinations were given. Urine was collected and radioactivity measured. Torasemide plus sodium chloride gave better {sup 76}Br elimination than the other diuretics. In a second experiment, rats were given [{sup 76}Br]BrdU. After the radioactivity injection, the rats of the treatment group were given torasemide plus NaCl. At 44 h after the radioactivity injection, the radioactivity concentration and the fraction incorporated into DNA were measured in different organs. Using diuretics, the elimination of [{sup 76}Br]bromide was increased. The radioactivity decreased 30-50% in most of the organs but the highest radioactivity uptake was found in the organs with more active DNA synthesis. This method may facilitate the use of [{sup 76}Br]BrdU as a tracer for DNA synthesis using PET.

  8. Elimination of nonspecific radioactivity from [76Br]bromide in PET study with [76Br]bromodeoxyuridine

    International Nuclear Information System (INIS)

    Li Lu; Bergstroem, Mats; Fasth, Karl-Johan; Wu Feng; Eriksson, Barbro; Laangstroem, Bengt

    1999-01-01

    [ 76 Br]Bromodeoxyuridine ([ 76 Br]BrdU) might allow a determination of proliferation in vivo using positron emission tomography (PET), but only with consideration of organ nonspecific radioactivity constituted by [ 76 Br]bromide. A first study assessed the potential of diuretics to eliminate [ 76 Br]bromide. [ 76 Br]Bromide was injected in the vein of rats and different diuretic combinations were given. Urine was collected and radioactivity measured. Torasemide plus sodium chloride gave better 76 Br elimination than the other diuretics. In a second experiment, rats were given [ 76 Br]BrdU. After the radioactivity injection, the rats of the treatment group were given torasemide plus NaCl. At 44 h after the radioactivity injection, the radioactivity concentration and the fraction incorporated into DNA were measured in different organs. Using diuretics, the elimination of [ 76 Br]bromide was increased. The radioactivity decreased 30-50% in most of the organs but the highest radioactivity uptake was found in the organs with more active DNA synthesis. This method may facilitate the use of [ 76 Br]BrdU as a tracer for DNA synthesis using PET

  9. Determination of nuclear cross-section of 81Br (n,,,) Br82 reaction by ...

    African Journals Online (AJOL)

    ... flux of 4.2 x 1013 n cm-2 s-1. The BaBr2 was chemically processed and measured as Hydrogen Bromide (HBr82). The value of nuclear cross-section was determined to be 2.1 0.2 barns, which falls within the range of values as previously reported elsewhere. (Journal of Applied Science and Technology: 2001 6(1-2): 4-6) ...

  10. Cytotaxonomy of North African species of <i>Delphinium> L. sect. <i>Delphinium> (<i>Ranunculaceae>

    Directory of Open Access Journals (Sweden)

    Blanché, César

    1990-05-01

    Full Text Available Both chromosome numbers and karyotype structure from 15 wild North-African populations of <i>Delphinium> L. sect. <i>Delphinium> were studied. <i>Delphinium balansaei> Boiss. & Reuter, with a more symmetrical karyotype, appears as a possible perennial ancestor of' the remaining annuals with highly asymmetrical and shorter karyotype. A taxonomical reorganization of this section is proposed: two new series (ser. <i>Macropetala> ser. nova and ser. <i>Balansae> ser. nova. and two new nomenclatural combinations (<i>D. nanumi> subsp. <i>alboliliaceum> and <i>D. nanumi> subsp. <i>elongatum> are proposed.<br>>S'han estudiat els nombres cromosòmics i l'estructura deis cariotipus de 15 poblacions nordafricanes de <i>Delphinium> L. sect. <i>Delphinium. Delphinium balansaei> Boiss. & Reuter, amb cariotipus mes simètric, apareix com a possible ancestre perenne de la resta d’espècies anuals amb cariotipus més asimètric i més curt. Es proposa una reorganització taxonòmica de la secció, d'on es descriu en dues series noves (ser. <i>Macropetala> ser. nova i ser. <i>Balansae> ser. nova. i es proposen dues combinacions noves (<i>D. nanumi> subsp. <i>alboliliaceum> and <i>D. nanumi> subsp. <i>elongatum>.

  11. Humidity-Induced Photoluminescence Hysteresis in Variable Cs/Br Ratio Hybrid Perovskites.

    Science.gov (United States)

    Howard, John M; Tennyson, Elizabeth M; Barik, Sabyasachi; Szostak, Rodrigo; Waks, Edo; Toney, Michael F; Nogueira, Ana F; Neves, Bernardo R A; Leite, Marina S

    2018-06-12

    Hybrid organic-inorganic perovskites containing Cs are a promising new material for light-absorbing and light-emitting optoelectronics. However, the impact of environmental conditions on their optical properties is not fully understood. Here, we elucidate and quantify the influence of distinct humidity levels on the charge carrier recombination in Cs x FA 1- x Pb(I y Br 1- y ) 3 perovskites. Using in situ environmental photoluminescence (PL), we temporally and spectrally resolve light emission within a loop of critical relative humidity (rH) levels. Our measurements show that exposure up to 35% rH increases the PL emission for all Cs (10-17%) and Br (17-38%) concentrations investigated here. Spectrally, samples with larger Br concentrations exhibit PL redshift at higher humidity levels, revealing water-driven halide segregation. The compositions considered present hysteresis in their PL intensity upon returning to a low-moisture environment due to partially reversible hydration of the perovskites. Our findings demonstrate that the Cs/Br ratio strongly influences both the spectral stability and extent of light emission hysteresis. We expect our method to become standard when testing the stability of emerging perovskites, including lead-free options, and to be combined with other parameters known for affecting material degradation, e.g., oxygen and temperature.

  12. Investigation of LaBr3:Ce probe for gamma-ray spectroscopy and dosimetry

    Science.gov (United States)

    Maghraby, Ahmed M.; Alzimami, K. S.; Alkhorayef, M. A.; Alsafi, K. G.; Ma, A.; Alfuraih, A. A.; Alghamdi, A. A.; Spyrou, N. M.

    2014-02-01

    The main thrust of this work is the investigation of performance of relatively new commercial LaBr3:Ce probe (Inspector 1000™ with LaBr3:Ce crystal) for gamma-ray spectroscopy and dosimetry measurements in comparison to LaCl3:Ce and NaI:Tl scintillators. The crystals were irradiated by a wide range of energies (57Co, 22Na, 18F, 137Cs and 60Co). The study involved recording of detected spectra and measurement of energy resolution, photopeak efficiency, internal radioactivity measurements as well as dose rate. The Monte Carlo package, Geant4 Application for Tomographic Emission (GATE) was used to validate the experiments. Overall results showed very good agreement between the measurements and the simulations. The LaBr3:Ce crystal has excellent energy resolution, energy resolutions of (3.37±0.05)% and (2.98±0.07)% for a 137Cs 662 keV and a 60Co 1332 keV gamma-ray point sources respectively, were recorded. The disadvantage of the lanthanum halide scintillators is their internal radioactivity. Inspector 1000™ with LaBr3:Ce scintillator has shown an accurate and quick dose measurements at Positron Emission Tomography (PET) Units which allows accurate assessment of the radiation dose received by staff members compared to the use of electronic personal dosimeters (EPD).

  13. Flexible All-Inorganic Perovskite CsPbBr3 Nonvolatile Memory Device.

    Science.gov (United States)

    Liu, Dongjue; Lin, Qiqi; Zang, Zhigang; Wang, Ming; Wangyang, Peihua; Tang, Xiaosheng; Zhou, Miao; Hu, Wei

    2017-02-22

    All-inorganic perovskite CsPbX 3 (X = Cl, Br, or I) is widely used in a variety of photoelectric devices such as solar cells, light-emitting diodes, lasers, and photodetectors. However, studies to understand the flexible CsPbX 3 electrical application are relatively scarce, mainly due to the limitations of the low-temperature fabricating process. In this study, all-inorganic perovskite CsPbBr 3 films were successfully fabricated at 75 °C through a two-step method. The highly crystallized films were first employed as a resistive switching layer in the Al/CsPbBr 3 /PEDOT:PSS/ITO/PET structure for flexible nonvolatile memory application. The resistive switching operations and endurance performance demonstrated the as-prepared flexible resistive random access memory devices possess reproducible and reliable memory characteristics. Electrical reliability and mechanical stability of the nonvolatile device were further tested by the robust current-voltage curves under different bending angles and consecutive flexing cycles. Moreover, a model of the formation and rupture of filaments through the CsPbBr 3 layer was proposed to explain the resistive switching effect. It is believed that this study will offer a new setting to understand and design all-inorganic perovskite materials for future stable flexible electronic devices.

  14. Irradiation of novel MTR fuel plates in BR2

    International Nuclear Information System (INIS)

    Verboomen, B.; Aoust, Th.; Beeckmans De Westmeerbeeck, A.; De Raedt, Ch.

    2000-01-01

    Since the end of 1999, novel MTR fuel plates with very high-density meat are being irradiated in BR2. The purpose of the irradiation is to investigate the behaviour of these fuel plates under very severe reactor operation conditions. The novel fuel plates are inserted in two standard six-tube BR2 fuel elements in the locations normally occupied by the standard outer fuel plates. The irradiation in BR2 was prepared by carrying out detailed neutron Monte Carlo calculations of the whole BR2 core containing the two experimental fuel elements for various positions in the reactor and for various azimuthal orientations of the fuel elements. Comparing the thus determined fission density levels and azimuthal profiles in the new MTR fuel plates irradiated in the various channels allowed the experimenters to choose the most appropriate BR2 channel and the most appropriate fuel element orientation. (author)

  15. Zn2(TeO3Br2

    Directory of Open Access Journals (Sweden)

    Mats Johnsson

    2008-05-01

    Full Text Available Single crystals of dizinc tellurium dibromide trioxide, Zn2(TeO3Br2, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound has a layered crystal structure in which the building units are [ZnO4Br] distorted square pyramids, [ZnO2Br2] distorted tetrahedra, and [TeO3E] tetrahedra (E being the 5s2 lone pair of Te4+ joined through sharing of edges and corners to form layers of no net charge. Bromine atoms and tellurium lone pairs protrude from the surfaces of each layer towards adjacent layers. This new compound Zn2(TeO3Br2 is isostructural with the synthetic compounds Zn2(TeO3Cl2, CuZn(TeO32, Co2(TeO3Br2 and the mineral sophiite, Zn2(SeO3Cl2.

  16. Emission characteristics of Xe-RbBr plasma

    Science.gov (United States)

    Heneral, A. A.; Avtaeva, S. V.

    2017-12-01

    The luminescence spectra of the longitudinal pulsed-periodic discharge in Xe-RbBr gas-vapour mixtures at low pressures are experimentally studied. Conditions for obtaining strong UV radiation of XeBr* exiplex molecules in the spectral range of 200-425 nm are found. The greatest output of the XeBr* UV radiation is provided at temperature of the gas-discharge tube walls of ~1000 K. The maximum UV emission power of the whole plasma volume is 4.8 W. Formation of XeBr* exciplex molecules in the pulsed-periodic discharge in Xe-RbBr gas-vapour mixtures at low pressures is discussed.

  17. Rashba split surface states in BiTeBr

    International Nuclear Information System (INIS)

    Eremeev, S V; Rusinov, I P; Nechaev, I A; Chulkov, E V

    2013-01-01

    Within density functional theory, we study the bulk band structure and surface states of BiTeBr. We consider both ordered and disordered phases, which differ in atomic order in the Te–Br sublattice. On the basis of relativistic ab initio calculations, we show that the ordered BiTeBr is energetically preferable as compared with the disordered one. We demonstrate that both Te- and Br-terminated surfaces of the ordered BiTeBr hold surface states with a giant spin–orbit splitting. The Te-terminated surface-state spin splitting has Rashba-type behavior with the coupling parameter α R ∼ 2 eVÅ. (paper)

  18. What is the best bonding model of the (σ-H-BR) species bound to a transition metal? Bonding analysis in complexes [(H)2Cl(PMe3)2M(σ-H-BR)] (M = Fe, Ru, Os).

    Science.gov (United States)

    Pandey, Krishna K

    2012-03-21

    Density Functional Theory calculations have been performed for the σ-hydroboryl complexes of iron, ruthenium and osmium [(H)(2)Cl(PMe(3))(2)M(σ-H-BR)] (M = Fe, Ru, Os; R = OMe, NMe(2), Ph) at the BP86/TZ2P/ZORA level of theory in order to understand the interactions between metal and HBR ligands. The calculated geometries of the complexes [(H)(2)Cl(PMe(3))(2)Ru(HBNMe(2))], [(H)(2)Cl(PMe(3))(2)Os(HBR)] (R = OMe, NMe(2)) are in excellent agreement with structurally characterized complexes [(H)(2)Cl(P(i)Pr(3))(2)Os(σ-H-BNMe(2))], [(H)(2)Cl(P(i)Pr(3))(2)Os{σ-H-BOCH(2)CH(2)OB(O(2)CH(2)CH(2))}] and [(H)(2)Cl(P(i)Pr(3))(2)Os(σ-H-BNMe(2))]. The longer calculated M-B bond distance in complex [(H)(2)Cl(PMe(3))(2)M(σ-H-BNMe(2))] are due to greater B-N π bonding and as a result, a weaker M-B π-back-bonding. The B-H2 bond distances reveal that (i) iron complexes contain bis(σ-borane) ligand, (ii) ruthenium complexes contain (σ-H-BR) ligands with a stretched B-H2 bond, and (iii) osmium complexes contain hydride (H2) and (σ-H-BR) ligands. The H-BR ligands in osmium complexes are a better trans-directing ligand than the Cl ligand. Values of interaction energy, electrostatic interaction, orbital interaction, and bond dissociation energy for interactions between ionic fragments are very large and may not be consistent with M-(σ-H-BR) bonding. The EDA as well as NBO and AIM analysis suggest that the best bonding model for the M-σ-H-BR interactions in the complexes [(H)(2)Cl(PMe(3))(2)M(σ-H-BR)] is the interaction between neutral fragments [(H)(2)Cl(PMe(3))(2)M] and [σ-H-BR]. This becomes evident from the calculated values for the orbital interactions. The electron configuration of the fragments which is shown for C in Fig. 1 experiences the smallest change upon the M-σ-H-BR bond formation. Since model C also requires the least amount of electronic excitation and geometry changes of all models given by the ΔE(prep) values, it is clearly the most appropriate choice of

  19. Investigation of anti-solvent induced optical properties change of cesium lead bromide iodide mixed perovskite (CsPbBr3-xIx) quantum dots.

    Science.gov (United States)

    Yuan, Lin; Patterson, Robert; Wen, Xiaoming; Zhang, Zhilong; Conibeer, Gavin; Huang, Shujuan

    2017-10-15

    Cesium lead halide (CsPbX 3 , X=Cl, Br, I) perovskites are a new material system that has attracted a lot of research focus. Its tunable band gap and better thermal stability than organic lead halide perovskite give it the potential for applications in optoelectronic devices such as light-emitting diodes and solar cells. Here we have synthesized CsPbBr 3-x I x perovskite quantum dots (QDs) via a solution process, and then have selected three different anti-solvents to purify the product. A significant effect on optical properties of CsPbBr 3-x I x was found after the centrifugation process. Up to a ∼40nm shift was observed in mixed halide CsPbBr 3-x I x QDs in both absorbance and PL spectra after purification while there was no obvious change in pure CsPbBr 3 when it was subjected to the same purification steps. XPS analysis shows that the Br:I ratio of the CsPbBr 3-x I x QDs had changed as a result of exposure to the anti-solvent, causing the change of the band gap and shift of the spectra. It is also shown that iodine can be removed more easily than bromine during the anti-solvent purification. Ab-initio simulations of small CsPbBr 3-x I x atomic clusters suggest that exposed Cs ions on Cs-terminated facets are the first species to be attacked by hydrophilic molecules, likely dragging halide ions into solution with them to maintain overall charge neutrality in the material. Charge carrier recombination rates were found to be unchanged and all samples maintained a good PL quantum yield which was more than 44%. Copyright © 2017. Published by Elsevier Inc.

  20. Superconductivity in intercalated and substituted Y2Br2C2

    International Nuclear Information System (INIS)

    Baecker, M.; Simon, A.; Kremer, R.K.; Mattausch, H.J.; Dronskowski, R.; Rouxel, J.

    1996-01-01

    Layer compounds of the type Y 2 X 2 C 2 (X=Cl, Br, I) show superconductivity at temperatures between 2.3 and 11.2 K. The transition temperature is related to the tendency of conduction electrons toward pairwise localization in C 2 -π * states at the Fermi level, and changes with the concentration of valence electrons, which is varied by intercalation of Na. (orig.)

  1. Density Functional Study of Structures and Electron Affinities of BrO4F/BrO4F-

    Directory of Open Access Journals (Sweden)

    Wei Li

    2009-07-01

    Full Text Available The structures, electron affinities and bond dissociation energies of BrO4F/BrO4F− species have been investigated with five density functional theory (DFT methods with DZP++ basis sets. The planar F-Br…O2…O2 complexes possess 3A' electronic state for neutral molecule and 4A' state for the corresponding anion. Three types of the neutral-anion energy separations are the adiabatic electron affinity (EAad, the vertical electron affinity (EAvert, and the vertical detachment energy (VDE. The EAad value predicted by B3LYP method is 4.52 eV. The bond dissociation energies De (BrO4F → BrO4-mF + Om (m = 1-4 and De- (BrO4F- → BrO4-mF- + Om and BrO4F- → BrO4-mF + Om- are predicted. The adiabatic electron affinities (EAad were predicted to be 4.52 eV for F-Br…O2…O2 (3A'← 4A' (B3LYP method.

  2. Development of source-less efficiency calibration procedure for CeBr3 based gamma spectrometry system

    International Nuclear Information System (INIS)

    Verma, Amit K.; Narayani, K.; Pant, Amar D.; Bhosale, Nitin; Anilkumar, S.; Palani Selvam, T.

    2018-01-01

    Scintillation spectrometers are widely used in detection and spectrometry of gamma photons. Sodium Iodide (NaI(Tl)) is the most commonly used scintillation detector for gamma ray spectrometry. However for portable application that require higher efficiency and better resolution Cerium Bromide (CeBr 3 ) crystals are more suitable than NaI(Tl) crystals. CeBr 3 detectors have high light output (∼ 68,000 photons/MeV), good proportionality, fast response and better energy resolution (<4% for 662 keV of 137 Cs), which makes it very promising detector for gamma ray spectrometry. In the present work, experimental and Monte Carlo based efficiencies for CeBr 3 detector for 137 Cs and 60 Co were evaluated

  3. Elimination mechanisms of Br2+ and Br+ in photodissociation of 1,1- and 1,2-dibromoethylenes using velocity imaging technique

    International Nuclear Information System (INIS)

    Hua Linqiang; Zhang Bing; Lee, Wei-Bin; Chao, Meng-Hsuan; Lin, King-Chuen

    2011-01-01

    Elimination pathways of the Br 2 + and Br + ionic fragments in photodissociation of 1,2- and 1,1-dibromoethylenes (C 2 H 2 Br 2 ) at 233 nm are investigated using time-of-flight mass spectrometer equipped with velocity ion imaging. The Br 2 + fragments are verified not to stem from ionization of neutral Br 2 , that is a dissociation channel of dibromoethylenes reported previously. Instead, they are produced from dissociative ionization of dibromoethylene isomers. That is, C 2 H 2 Br 2 is first ionized by absorbing two photons, followed by the dissociation scheme, C 2 H 2 Br 2 + + hv→Br 2 + + C 2 H 2 . 1,2-C 2 H 2 Br 2 gives rise to a bright Br 2 + image with anisotropy parameter of -0.5 ± 0.1; the fragment may recoil at an angle of ∼66 deg. with respect to the C = C bond axis. However, this channel is relatively slow in 1,1-C 2 H 2 Br 2 such that a weak Br 2 + image is acquired with anisotropy parameter equal to zero, indicative of an isotropic recoil fragment distribution. It is more complicated to understand the formation mechanisms of Br + . Three routes are proposed for dissociation of 1,2-C 2 H 2 Br 2 , including (a) ionization of Br that is eliminated from C 2 H 2 Br 2 by absorbing one photon, (b) dissociation from C 2 H 2 Br 2 + by absorbing two more photons, and (c) dissociation of Br 2 + . Each pathway requires four photons to release one Br + , in contrast to the Br 2 + formation that involves a three-photon process. As for 1,1-C 2 H 2 Br 2 , the first two pathways are the same, but the third one is too weak to be detected.

  4. Estimating BrAC from transdermal alcohol concentration data using the BrAC estimator software program.

    Science.gov (United States)

    Luczak, Susan E; Rosen, I Gary

    2014-08-01

    Transdermal alcohol sensor (TAS) devices have the potential to allow researchers and clinicians to unobtrusively collect naturalistic drinking data for weeks at a time, but the transdermal alcohol concentration (TAC) data these devices produce do not consistently correspond with breath alcohol concentration (BrAC) data. We present and test the BrAC Estimator software, a program designed to produce individualized estimates of BrAC from TAC data by fitting mathematical models to a specific person wearing a specific TAS device. Two TAS devices were worn simultaneously by 1 participant for 18 days. The trial began with a laboratory alcohol session to calibrate the model and was followed by a field trial with 10 drinking episodes. Model parameter estimates and fit indices were compared across drinking episodes to examine the calibration phase of the software. Software-generated estimates of peak BrAC, time of peak BrAC, and area under the BrAC curve were compared with breath analyzer data to examine the estimation phase of the software. In this single-subject design with breath analyzer peak BrAC scores ranging from 0.013 to 0.057, the software created consistent models for the 2 TAS devices, despite differences in raw TAC data, and was able to compensate for the attenuation of peak BrAC and latency of the time of peak BrAC that are typically observed in TAC data. This software program represents an important initial step for making it possible for non mathematician researchers and clinicians to obtain estimates of BrAC from TAC data in naturalistic drinking environments. Future research with more participants and greater variation in alcohol consumption levels and patterns, as well as examination of gain scheduling calibration procedures and nonlinear models of diffusion, will help to determine how precise these software models can become. Copyright © 2014 by the Research Society on Alcoholism.

  5. Photodissociation of C{sub 3}H{sub 5}Br and C{sub 4}H{sub 7}Br at 234 nm

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Kook; Paul, Dababrata; Hong, Ki Ryong; Cho, Ha Na; Kim, Tae Kyu [Pusan National University, Busan (Korea, Republic of); Lee, Kyoung Seok [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2012-01-15

    The photodissociation dynamics of cyclopropyl bromide (C-3H{sub 5}Br) and cyclobutyl bromide (C{sub 4}H{sub 7}Br) at 234 nm was investigated. A two-dimensional photofragment ion-imaging technique coupled with a [2+1] resonance enhanced multiphoton ionization scheme was utilized to obtain speed and angular distributions of the nascent Br({sup 2}P{sub 3/2}) and Br*({sup 2}P{sub 1/2}) atoms. The recoil anisotropies for the Br and Br* channels were measured to be βBr = 0.92 ± 0.03 and βBr* = 1.52 ± 0.04 for C{sub 3}H{sub 5}Br and βBr = 1.10 ± 0.03 and βBr* = 1.49 ± 0.05 for C{sub 4}H{sub 7}Br. The relative quantum yield for Br was found to be ΦBr = 0.13 ± 0.03 and for C{sub 3}H{sub 5}Br and C{sub 4}H{sub 7}Br, respectively. The soft radical limit of the impulsive model adequately modeled the related energy partitioning. The nonadiabatic transition probability from the 3A' and 4A' potential energy surfaces was estimated and discussed.

  6. Suppression of Rapidly Progressive Mouse Glomerulonephritis with the Non-Steroidal Mineralocorticoid Receptor Antagonist BR-4628.

    Science.gov (United States)

    Ma, Frank Y; Han, Yingjie; Nikolic-Paterson, David J; Kolkhof, Peter; Tesch, Greg H

    2015-01-01

    Steroidal mineralocorticoid receptor antagonists (MRAs) are effective in the treatment of kidney disease; however, the side effect of hyperkalaemia, particularly in the context of renal impairment, is a major limitation to their clinical use. Recently developed non-steroidal MRAs have distinct characteristics suggesting that they may be superior to steroidal MRAs. Therefore, we explored the benefits of a non-steroidal MRA in a model of rapidly progressive glomerulonephritis. Accelerated anti-glomerular basement membrane (GBM) glomerulonephritis was induced in groups of C57BL/6J mice which received no treatment, vehicle or a non-steroidal MRA (BR-4628, 5mg/kg/bid) from day 0 until being killed on day 15 of disease. Mice were examined for renal injury. Mice with anti-GBM glomerulonephritis which received no treatment or vehicle developed similar disease with severe albuminuria, impaired renal function, glomerular tuft damage and crescents in 40% of glomeruli. In comparison, mice which received BR-4628 displayed similar albuminuria, but had improved renal function, reduced severity of glomerular tuft lesions and a 50% reduction in crescents. The protection seen in BR-4628 treated mice was associated with a marked reduction in glomerular macrophages and T-cells and reduced kidney gene expression of proinflammatory (CCL2, TNF-α, IFN-γ) and profibrotic molecules (collagen I, fibronectin). In addition, treatment with BR-4626 did not cause hyperkalaemia or increase urine Na+/K+ excretion (a marker of tubular dysfunction). The non-steroidal MRA (BR-4628) provided substantial suppression of mouse crescentic glomerulonephritis without causing tubular dysfunction. This finding warrants further investigation of non-steroidal MRAs as a therapy for inflammatory kidney diseases.

  7. Suppression of Rapidly Progressive Mouse Glomerulonephritis with the Non-Steroidal Mineralocorticoid Receptor Antagonist BR-4628.

    Directory of Open Access Journals (Sweden)

    Frank Y Ma

    Full Text Available Steroidal mineralocorticoid receptor antagonists (MRAs are effective in the treatment of kidney disease; however, the side effect of hyperkalaemia, particularly in the context of renal impairment, is a major limitation to their clinical use. Recently developed non-steroidal MRAs have distinct characteristics suggesting that they may be superior to steroidal MRAs. Therefore, we explored the benefits of a non-steroidal MRA in a model of rapidly progressive glomerulonephritis.Accelerated anti-glomerular basement membrane (GBM glomerulonephritis was induced in groups of C57BL/6J mice which received no treatment, vehicle or a non-steroidal MRA (BR-4628, 5mg/kg/bid from day 0 until being killed on day 15 of disease. Mice were examined for renal injury.Mice with anti-GBM glomerulonephritis which received no treatment or vehicle developed similar disease with severe albuminuria, impaired renal function, glomerular tuft damage and crescents in 40% of glomeruli. In comparison, mice which received BR-4628 displayed similar albuminuria, but had improved renal function, reduced severity of glomerular tuft lesions and a 50% reduction in crescents. The protection seen in BR-4628 treated mice was associated with a marked reduction in glomerular macrophages and T-cells and reduced kidney gene expression of proinflammatory (CCL2, TNF-α, IFN-γ and profibrotic molecules (collagen I, fibronectin. In addition, treatment with BR-4626 did not cause hyperkalaemia or increase urine Na+/K+ excretion (a marker of tubular dysfunction.The non-steroidal MRA (BR-4628 provided substantial suppression of mouse crescentic glomerulonephritis without causing tubular dysfunction. This finding warrants further investigation of non-steroidal MRAs as a therapy for inflammatory kidney diseases.

  8. Flg22-Triggered Immunity Negatively Regulates Key BR Biosynthetic Genes.

    Science.gov (United States)

    Jiménez-Góngora, Tamara; Kim, Seong-Ki; Lozano-Durán, Rosa; Zipfel, Cyril

    2015-01-01

    In plants, activation of growth and activation of immunity are opposing processes that define a trade-off. In the past few years, the growth-promoting hormones brassinosteroids (BR) have emerged as negative regulators of pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI), promoting growth at the expense of defense. The crosstalk between BR and PTI signaling was described as negative and unidirectional, since activation of PTI does not affect several analyzed steps in the BR signaling pathway. In this work, we describe that activation of PTI by the bacterial PAMP flg22 results in the reduced expression of BR biosynthetic genes. This effect does not require BR perception or signaling, and occurs within 15 min of flg22 treatment. Since the described PTI-induced repression of gene expression may result in a reduction in BR biosynthesis, the crosstalk between PTI and BR could actually be negative and bidirectional, a possibility that should be taken into account when considering the interaction between these two pathways.

  9. La Alpaca -vaatemerkin brändäys

    OpenAIRE

    Lehtinen, Laura

    2013-01-01

    Tämä opinnäytetyö käsittelee brändin vahvistamista ja brändiohjeiston luomista vaa-tealan yritykselle La Alpacalle. La Alpaca on suomalainen vaatemerkki, joka suunnit-telee, tuottaa ja myy alpakanvillasta valmistettuja tuotteita. Materiaalin ainutlaatuisuus ja hienous ovat olleet osa yrityksen identiteettiä alusta asti. Brändin lisäksi työssä on tutkittu kaupankäynnin rakenteellista muuttumista perinteisestä myymälätoiminnasta verkkomyyntiin. Työn tavoitteena on ollut luoda materiaalin tun...

  10. Magnetic diagnostic plasma position in the TCA/BR tokamak

    International Nuclear Information System (INIS)

    Galvao, R.M.O.; Kuznetsov, Yu.K.; Nascimento, I.C.

    1996-01-01

    The cross-section of the plasma column is TCA/BR has a nearly circular plasma shape. This allows implementation of simplified methods of magnetic diagnostics. Although these methods were in may tokamaks and are well described, their accuracies are not clearly defined because the very simplified theoretical model of plasma equilibrium on which they are based differs from the real conditions in tokamaks like TCA/BR. In this paper we present the methods of plasma position diagnostics in TCA/BR from external magnetic measurements with an error analysis. (author). 4 refs., 3 figs

  11. Dicty_cDB: FC-BR21 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available FC (Link to library) FC-BR21 (Link to dictyBase) - - - Contig-U15384-1 | Contig-U16443-1 FC-BR2...1P (Link to Original site) FC-BR21F 551 FC-BR21Z 122 FC-BR21P 673 - - Show FC-BR21 Library FC (L...ink to library) Clone ID FC-BR21 (Link to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Cont...ig-U15384-1 | Contig-U16443-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/FC/FC-BR/FC-BR2...1Q.Seq.d/ Representative seq. ID FC-BR21P (Link to Original site) Representative DNA sequence >FC-BR21 (FC-BR2

  12. Psoralens cleave pBR322 DNA under ultraviolet radiation

    International Nuclear Information System (INIS)

    Kagan, J.; Xinsheng Chen; Wang, T.P.

    1992-01-01

    Supercoiled (SC) pBR322 was used to probe the recent claim that 5-geranoxylpsoralen (5-GOP) did not photoreact with DNA. Contrary to expectations, 5-GOP was found to damage DNA in the presence of UV-A through two competing pathways; (a) single strand breaks, identified by the conversion of supercoiled into open circular and linear DNA, and (b) cross-linking, revealed by the fluence-dependent decrease in the extent of denaturation of the double stranded supercoiled DNA to single stranded circular DNA. In addition, a fluence-dependent modification reduced the ability of the restriction enzyme EcoR I to linearize the photosensitized DNA, and alkali-labile lesions were generated. Psoralen, 5-methoxypsoralen, and 8-methoxypsoralen, which are well-known to undergo cycloaddition to DNA, had a more pronounced effect on supercoiled DNA. Single strand breaks occurred more readily than with 5-GOP, and the surviving SC form remaining had reduced electrophoretic mobility in agarose gels. In all cases, the DNA damage was more prominent when oxygen was absent. (author)

  13. Equilibrium reconstruction in the TCA/Br tokamak; Reconstrucao do equilibrio no tokamak TCA/BR

    Energy Technology Data Exchange (ETDEWEB)

    Sa, Wanderley Pires de

    1996-12-31

    The accurate and rapid determination of the Magnetohydrodynamic (MHD) equilibrium configuration in tokamaks is a subject for the magnetic confinement of the plasma. With the knowledge of characteristic plasma MHD equilibrium parameters it is possible to control the plasma position during its formation using feed-back techniques. It is also necessary an on-line analysis between successive discharges to program external parameters for the subsequent discharges. In this work it is investigated the MHD equilibrium configuration reconstruction of the TCA/BR tokamak from external magnetic measurements, using a method that is able to fast determine the main parameters of discharge. The thesis has two parts. Firstly it is presented the development of an equilibrium code that solves de Grad-Shafranov equation for the TCA/BR tokamak geometry. Secondly it is presented the MHD equilibrium reconstruction process from external magnetic field and flux measurements using the Function Parametrization FP method. this method. This method is based on the statistical analysis of a database of simulated equilibrium configurations, with the goal of obtaining a simple relationship between the parameters that characterize the equilibrium and the measurements. The results from FP are compared with conventional methods. (author) 68 refs., 31 figs., 16 tabs.

  14. Double-wall carbon nanotubes doped with different Br2 doping levels: a resonance Raman study.

    Science.gov (United States)

    do Nascimento, Gustavo M; Hou, Taige; Kim, Yoong Ahm; Muramatsu, Hiroyuki; Hayashi, Takuya; Endo, Morinobu; Akuzawa, Noboru; Dresselhaus, Mildred S

    2008-12-01

    This report focuses on the effects of different Br2 doping levels on the radial breathing modes of "double-wall carbon nanotube (DWNT) buckypaper". The resonance Raman profile of the Br2 bands are shown for different DWNT configurations with different Br2 doping levels. Near the maximum intensity of the resonance Raman profile, mainly the Br2 molecules adsorbed on the DWNT surface contribute strongly to the observed omega(Br-Br) Raman signal.

  15. Kinetics of the Reactions of O((sup 3)P) and Cl((sup 2)P) with HBr and Br2

    Science.gov (United States)

    Nicovich, J. M.; Wine, P. H.

    1997-01-01

    A laser flash photolysis-resonance fluorescence technique has been employed to study the kinetics of reactions (1)-(4) as a function of temperature. (1) O((sup 3)P) + Br2 yields BrO + Br((sup 2)P(sub 3/2)) at 255-350 K; (2) Cl((sup 2)P) + Br2 yields BrCl + Br((sup 2)P(sub 3/2)) at 298-401 K; (3) O((sup 3)P) + HBr yields OH + Br((sup 2)P(sub J)) at 250-402 K; (4) Cl((sup 2)P) + HBr yields HCl + Br((sup 2)P(sub J)) at 257-404 K. In all cases, the concentration of the excess reagent, i.e, HBr or Br2, was measured in situ in the slow flow system by UV-visible photometry. Heterogeneous dark reactions between XBr (X equals H or Br) and the photolytic precursors for Cl((sup 2)P) and O((sup 3)P) (Cl2 and O3, respectively) were avoided by injecting minimal amounts of precursor into the reaction mixture immediately upstream from the reaction zone. The following Arrhenius expressions summarize our results (errors are 2 sigma and represent precision only, units are cu cm/(molecule.s): k(sub 1) = (1.76 +/- 0.80) x 10(exp -11 exp[(40 +/- 100)/T]; k(sub 2) = (2.40 +/- 1.25) x 12(exp -10) exp[-(144 +/- 176)/T]; k(sub 3) = (5.11 +/- 2.82) x 10(exp -12) exp[-(1450 +/- 160)/T]; k(sub 4) = (2.25 +/- 0.56) x 10(exp -11) exp[-(400 +/- 80)/T]. The consistency (or lack thereof) of our results with those reported in previous kinetics and dynamics studies of reactions (1)-(4) is discussed.

  16. On the presence of <i>Vicia vicioidesi> in Alicante

    Directory of Open Access Journals (Sweden)

    Pérez-Haase, A.

    2008-12-01

    Full Text Available Please read the Spanish version of this Abstract.<br>>En el presente trabajo se actualiza el conocimiento corológico de la leguminosa <i>Vicia vicioidesi> (Desf. Cout. en la provincia de Alicante, aportando información sobre cinco nuevas poblaciones, que se añaden a la única localidad conocida previamente.

  17. Oxidation mechanisms of CF2Br2 and CH2Br2 induced by air nonthermal plasma.

    Science.gov (United States)

    Schiorlin, Milko; Marotta, Ester; Dal Molin, Marta; Paradisi, Cristina

    2013-01-02

    Oxidation mechanisms in air nonthermal plasma (NTP) at room temperature and atmospheric pressure were investigated in a corona reactor energized by +dc, -dc, or +pulsed high voltage.. The two bromomethanes CF(2)Br(2) and CH(2)Br(2) were chosen as model organic pollutants because of their very different reactivities with OH radicals. Thus, they served as useful mechanistic probes: they respond differently to the presence of humidity in the air and give different products. By FT-IR analysis of the postdischarge gas the following products were detected and quantified: CO(2) and CO in the case of CH(2)Br(2), CO(2) and F(2)C ═ O in the case of CF(2)Br(2). F(2)C ═ O is a long-lived oxidation intermediate due to its low reactivity with atmospheric radicals. It is however removed from the NTP processed gas by passage through a water scrubber resulting in hydrolysis to CO(2) and HF. Other noncarbon containing products of the discharge were also monitored by FT-IR analysis, including HNO(3) and N(2)O. Ozone, an important product of air NTP, was never detected in experiments with CF(2)Br(2) and CH(2)Br(2) because of the highly efficient ozone depleting cycles catalyzed by BrOx species formed from the bromomethanes. It is concluded that, regardless of the type of corona applied, CF(2)Br(2) reacts in air NTP via a common intermediate, the CF(2)Br radical. The possible reactions leading to this radical are discussed, including, for -dc activation, charge exchange with O(2)(-), a species detected by APCI mass spectrometry.

  18. Effect of Aromatic Oil on Phase Dynamics of S-SBR/BR Blends fro Passenger Car Tire Treads

    NARCIS (Netherlands)

    Rathi, Akansha; Hernández, M.; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.; Bergmann, C.; Trimbach, J.; Blume, Anke

    2015-01-01

    Even though S-SBR/BR blends are commonly used for passenger car tire treads, little is known about the phase dynamics arising from the local morphological heterogeneities. The present study aims at developing the understanding of: (i) the influence of aromatic oil on the dynamics of the individual

  19. Brüssel - unistus Euroopa pealinnast / Kristi Grishakov

    Index Scriptorium Estoniae

    Grishakov, Kristi

    2008-01-01

    Brüsseli linnaplaneerimise ajaloost, linnaehituslikest ja sotsiaalset laadi probleemidest, võimalikust tulevikust Euroopa pealinnana. Berlage Instituudi näitusest "A Vision for Brussels" Bozari kunstikeskuses

  20. On weakly BR-closed functions between topological spaces

    OpenAIRE

    Caldas, Miguel; Ekici, Erdal; Jafari, Saeid; Moshokoa, Seithuti P.

    2009-01-01

    In this paper, we offer a new class of functions called weakly BR-closed functions. Moreover, we investigate not only some of their basic properties but also their relationships with other types of already well-known functions.

  1. Monika Elisabeth Bründl, Lexikalische Dynamik – Kognitiv ...

    African Journals Online (AJOL)

    Information Technology

    as discussing the "building blocks" which enter into the formation of complex lexemes. ... atomic) semantic feature such as UNPLEASANT JUNK might have served the same ... Bründl discusses this question using bomb as an example (p. 163):.

  2. Measurement of the ratio of branching ratios BR(B+ → J/ψK+)/BR(B0 → J/φK0) and BR(B+ → J/ψK+)/BR(B+ → J/ψK*+)

    International Nuclear Information System (INIS)

    Atavales, J. B. G.

    1995-01-01

    A preliminary measurement of the ratio of branching ratios BR(B + → J/ψK + )/BR(B 0 → J/ψK 0 ) and BR(B + → J/ψK + )/BR(B + → J/ψK *+ ) is made by fully reconstructing each mode, where J/ψ → μ + μ - , K *+ → K 0 s π + and K 0 s → π + π - . The data were taken with the CDF detector during the 1993 run. The total integrated luminosity is ∼ 20pb -1 resulting in a sample of about 170 J/ψK ± , 50 J/ψK 0 S and 25 J/ψK *± candidate events. The results will be reported

  3. Performance evaluation of LaBr3: Ce scintillator

    International Nuclear Information System (INIS)

    Xie Ming; Lin Li; Liu Shihao; Xiao Peng; Xie Qingguo

    2012-01-01

    The cerium doped lanthanum bromide crystal (LaBr 3 : Ce) is a new kind of scintillator with many advantages such as good energy resolution, high light output, short decay time, good proportionality response. These properties make the LaBr 3 : Ce attractive substantial interest to use in the radiation detection. The energy resolution were investigated with Φ25 × 25 mm LaBr 3 : Ce coupled to a Hamamatsu R8900 photomultiplier tube. Energy resolution of 3.6% (FWHM) have been achieved for 511 keV photons ( 18 F source) at room temperature. Decay time constant of 20 ns have been acquired with a Hamamatsu fast-time-response R9800 photomultiplier tube. The results approve the excellent characterizations of LaBr 3 : Ce and imply its enormous potentiality in the radiation detectors of gamma-ray spectroscopy and PET. (authors)

  4. FeBr3-catalyzed dibromination of alkenes and alkynes

    Institute of Scientific and Technical Information of China (English)

    Yun Fa Zheng; Jian Yu; Guo Bing Yan; Xu Li; Song Luo

    2011-01-01

    The dibromination of alkenes and alkynes with bromosuccinimide and sodium bromide catalyzed by FeBr3 under mild conditions has been developed. The trans-dibromo compounds were exclusively obtained with excellent yields.

  5. GMO konverents Brüsselis / Nastja Pertsjonok

    Index Scriptorium Estoniae

    Pertsjonok, Nastja

    2007-01-01

    Brüsselis toimunud GMO-vabade piirkondade konverentsist, kus räägiti GMO-vabade piirkondade liikumisest, GMO-de lubamisest ja keelamisest ning hoiakutest nende suhtes Euroopa Liidus ja mujal maailmas

  6. Polymeric anionic networks using dibromine as a crosslinker; the preparation and crystal structure of [(C4H9)4N]2[Pt2Br10].(Br2)7 and [(C4H9)4N]2[PtBr4Cl2].(Br2)6.

    Science.gov (United States)

    Berkei, Michael; Bickley, Jamie F; Heaton, Brian T; Steiner, Alexander

    2002-09-21

    The reaction of M[PtX3(CO)] (M+ = [(C4H9)4N]+, X = Br, Cl) with an excess of Br2 gives the new platinum(IV) salts, [(C4H9)4N]2[Pt2Br10].(Br2)7, 1, and [(C4H9)4N]2[PtBr4Cl2].(Br2)6, 2, which, in the solid state, contain strong Br Br interactions resulting in the formation of polymeric networks; they could provide useful solid storage reservoirs for elemental bromine.

  7. Optical spectroscopy and Fermi surface studies of BiTeCl and BiTeBr

    Science.gov (United States)

    Martin, Catalin; Suslov, A. V.; Buvaev, S.; Hebard, A. F.; Bugnon, Philippe; Berger, Helmuth; Magrez, Arnaud; Tanner, D. B.

    2014-03-01

    The observation of a large bulk Rashba effect in the non-centrosymmetric semiconductors BiTeX(X=Cl, Br, I) has stimulated the interest in these sys- tems, as promising candidates for studying spin related phenomena and for the realization of spin devices. Here we present a comparative study of the electronic properties of BiTeCl and BiTeBr, determined from temperature dependent infrared spectroscopy and Shubnikov-de Haas oscillations. In par- ticular, we compare the angle dependence of quantum oscillations between the two compounds and discuss possible differences between the topology of their Fermi surfaces. Supported by NSF Cooperative Agreement DMR-1157490 to the National High Magnetic Field Laboratory.

  8. Life extension of the BR2 aluminium vessel

    International Nuclear Information System (INIS)

    Koonen, E.; Fabry, A.; Chaouadi, R.; Verwerft, M.; Raedt, C. de; Winckel, S. van; Wacquier, W.; Dadoumont, J.; Verwimp, A.

    2000-01-01

    The BR2 reactor has recently undergone a major refurbishment comprising the replacement of all vessel internals. The vessel itself however was not replaced. An important requalification programme has been executed to prove that the vessel would remain fit during the contemplated life extension period of BR2. Representative material samples could be obtained from the shroud surrounding the vessel. A comprehensive in-service inspection was carried out and a vessel surveillance programme has been established. (author)

  9. The Role of Adenosine A2BR in Metastatic Melanoma

    Science.gov (United States)

    2017-07-01

    burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense...would like to interrogate the role of adenosine receptor (A2BR) in regulating primary tumor growth and metastasis in experimental models of melanoma...The positive control was a triple negative breast cancer cell line, E0771. To interrogate the role of A2BR in aiding tumor metastasis, we used VeCad

  10. Charge exchange reactions and solar neutrino detection in 81Br

    International Nuclear Information System (INIS)

    Liu, K.F.; Gabbard, F.

    1983-01-01

    The feasibility of 81 Br as the detector of the solar neutrino flux hinges upon the knowledge of the Gamow-Teller matrix element from the ground state of 81 Br to the (5/2) - state at 0.457 MeV in 81 Kr. The possibility of obtaining this matrix element is discussed in terms of the (p,n) and ( 3 He, t) charge exchange reactions. .ID CR2009 .PG 98 112

  11. Radiosynthesis and pharmacokinetics of high specific activity /sup 75,77/Br-bromperidol, a potent butyrophenone neuroleptic

    International Nuclear Information System (INIS)

    Moerlein, S.M.; Stocklin, G.

    1984-01-01

    Bromperidol, 4-[4-(4-bromophenyl)-4-hydroxypiperidino]-4'- fluorobutyrophenone, is a potent neuroleptic which has found clinical use in the treatment of schizophrenia. Of the major dopaminergic receptor-binding ligands, bromperidol has the greatest specificity for binding to cerebral dopamine receptors (K/sub i/ = 3.7 nM) relative to competitive cerebral serotonin (K/sub i/ = 26 nM), α-adrenergic (K/sub i/ = 100 nM) or histamine (K/sub i/ = 700 nM) receptors. The authors have therefore prepared bromperidol labelled with no-carrier-added (n.c.a.) /sup 75/Br (t/sub 1/2/ = 1.6 hr β/sup +/) or /sup 77/Br (t/sub 1/2/ = 52 hr EC) for evaluation as a radiopharmaceutical for mapping cerebral dopamine receptor areas with PECT technology, as well as for non-invasive pharmacodynamic studies in man with conventional nuclear medicine equipment. 4-[4-(4-trimethylstannylphenyl)-4-hydroxypiperidino]-4'- fluorobutyrophenone, TMSn-P, was synthesized in 40% chemical yield by reaction of trimethylstannyl sodium with bromperidol. TMSn-P was purified by preparative HPLC and characterized by /sup 1/H-NMR and GC-MS. TMSn-P was radiobrominated in methanol using n.c.a. /sup 75/Br/sup -/ or /sup 77/Br/sup -/ and dichloramine-T as oxidizing agent. Product /sup 75,77/Br-bromperidol was separated from impurities, including chlorinated side-product halo-peridol, using HPLC (RP-18; MeOH/H/sub 2/O/Et/sub 3/N = 70/30/0.3). For a reaction time of 5 minutes, and an overall radiopharmaceutical production time of 30 minutes, /sup 75,77/Br-bromperidol was obtained in physiological saline solution with 40% radiochemical yield and a specific activity > 10,000 Ci/mmole. The pharmacokinetics in rodents and PECT studies in primates using /sup 75,77/Br-bromperidol are compared with that of previously-reported /sup 75,77/Br-brombenperidol

  12. Br2 elimination in 248-nm photolysis of CF2Br2 probed by using cavity ring-down absorption spectroscopy.

    Science.gov (United States)

    Hsu, Ching-Yi; Huang, Hong-Yi; Lin, King-Chuen

    2005-10-01

    By using cavity ring-down absorption spectroscopy technique, we have observed the channel of Br2 molecular elimination following photodissociation of CF2Br2 at 248 nm. A tunable laser beam, which is crossed perpendicular to the photolyzing laser beam in a ring-down cell, is used to probe the Br2 fragment in the B 3Piou+-X1Sigmag+ transition. The vibrational population is obtained in a nascent state, despite ring-down time as long as 500-1000 ns. The population ratio of Br2(v=1)/Br2(v=0) is determined to be 0.4+/-0.2, slightly larger than the value of 0.22 evaluated by Boltzmann distribution at room temperature. The quantum yield of the Br2 elimination reaction is also measured to be 0.04+/-0.01. This work provides direct evidence to support molecular elimination occurring in the CF2Br2 photodissociation and proposes a plausible pathway with the aid of ab initio potential-energy calculations. CF2Br2 is excited probably to the 1B1 and 3B2 states at 248 nm. As the C-Br bond is elongated upon excitation, the coupling of the 1A'(1B1) state to the high vibrational levels of the ground state X 1A'(1A1) may be enhanced to facilitate the process of internal conversion. After transition, the highly vibrationally excited CF2Br2 feasibly surpasses a transition barrier prior to decomposition. According to the ab initio calculations, the transition state structure tends to correlate with the intermediate state CF2Br+Br(CF2Br...Br) and the products CF2+Br2. A sequential photodissociation pathway is thus favored. That is, a single C-Br bond breaks, and then the free-Br atom moves to form a Br-Br bond, followed by the Br2 elimination. The formed Br-Br bond distance in the transition state tends to approach equilibrium such that the Br2 fragment may be populated in cold vibrational distribution. Observation of a small vibrational population ratio of Br2(v=1)Br2(v=0) agrees with the proposed mechanism.

  13. Chemical consequences of radioactive decay. 1. Study of 249Cf ingrowth into crystalline 249BkBr3: a new crystalline phase of CfBr3

    International Nuclear Information System (INIS)

    Young, J.P.; Haire, R.G.; Peterson, J.R.; Ensor, D.D.; Fellows, R.L.

    1980-01-01

    Spectrophotometric and x-ray powder diffraction methods have been applied to a study of the ingrowth of californium-249 by β - decay of berkelium-249 in crystalline 249 BkBr 3 . It was found that the Cf daughter grows in with the same oxidation state and crystal structure as the parent. Thus, six-coordinate BkBr 3 (AlCl 3 -type monoclinic structure) generates six-coordinate CfBr 3 , and eight-coordinate BkBr 3 (PuBr 3 -type orthorhombic structure) generates eight-coordinate CfBr 3 , a previously unknown form of CfBr 3 . It was also found that the daughter Cf(III) in the BkBr 3 parent compound can be reduced to Cf(II) by treatment with H 2 , as it can in pure CfBr 3 . 5 figures

  14. A biochemical defect in the repair of alkylated DNA in cells from an immunodeficient patient (46BR)

    International Nuclear Information System (INIS)

    Teo, I.A.; Broughton, B.C.; Day, R.S.; James, M.R.; Karran, P.; Mayne, L.V.; Lehmann, A.R.

    1983-01-01

    The fibroblast cell strain 46BR, derived from an immunodeficient individual, is hypersensitive to the lethal effects of a variety of DNA-damaging agents, this effect being particularly marked for monofunctional methylating agents. After U.V. irradiation 46BR cells show normal unscheduled DNA synthesis, daughter strand repair, and recovery of DNA and RNA synthesis. The inhibition of DNA replicative synthesis by U.V. is slightly less than that of normal cells. After gamma-irradiation the rejoining of strand breaks is normal as are the kinetics of replicative DNA synthesis. Following treatment with dimethylsulphate, replicative DNA synthesis is affected in a similar way to normal cells, unscheduled DNA synthesis may be increased relative to normal cells, but more strand breaks persist in 46BR than in normal cells. In addition 46BR cells are hypersensitive to the toxic effects of 3-aminobenzamide, an inhibitor of ADP-ribosyl transferase. This enzyme is involved in the ligation step of repair of alkylation damage. A hypothesis is presented suggesting that 46BR may be defective in DNA ligase I

  15. Improvement of solar cells performances by surface passivation using porous silicon chemically treated with LiBr solution

    Energy Technology Data Exchange (ETDEWEB)

    Haddadi, Ikbel; Dimassi, Wissem; Bousbih, Rabaa; Hajji, Massoud; Kanzari, M. Ali; Ezzaouia, Hatem [Laboratoire de Photovoltaique, Centre de Recherche et des Technologies de l' Energie, Hammam Lif (Tunisia)

    2011-03-15

    Solar cells need efficient light absorption to achieve high efficiencies. In this paper, we present a study on the immersion effect of porous silicon (PS) in a Lithium Bromide (LiBr) aqueous solution, followed by thermal annealing at 100 C for 30 min under nitrogen atmosphere on solar cells performances. The surface morphology was studied by Atomic Force Microscopy (AFM). All samples were analyzed by Fourier transmission infrared spectroscopy (FTIR) before and after LiBr immersion. Good electrical properties were observed after thermal annealing at 100 C for 30 min under nitrogen atmosphere. The reflection spectra of PS, before and after LiBr treatment, performed in the 300-1200 nm wavelength range, showed an important decrease of the reflectivity by this new treatment. A significant increase of the photoluminescence (PL) intensity was obtained after LiBr treatment. An enhancement of the light beam induced current (LBIC) as well as the internal quantum efficiency (IQE) were shown after LiBr treatment. I-V characteristics, under AM1.5 illumination, were improved owing to the increase of the minority carrier diffusion length (L) and an excellent enhancement of the surface recombination velocity (V{sub s}) (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. Radiation absorbed doses in the event of balloon rupture (BR) during endovascular brachytherapy (EB) using 188Re-perrhenate

    International Nuclear Information System (INIS)

    Angelides, S.; Hetherington, E.; Karolis, C.; Walker, B.; Jackson, T.; Knittel, T.; Friend, C.; Pitney, M.; Jepson, N.; Milross, C.; Lonergan, D.

    2000-01-01

    Full text: endovascular brachytherapy (EB) using liquid or solid radiation sources, is an effective emerging therapy for coronary artery disease. Liquid sources provide uniform radiation dose to the vessel wall. However the radiation burden in the unlikely event of BR is not insignificant. The aims of this study were to determine i) absorbed dose for various 188 Re radiopharmaceuticals in the event of BR, and ii) effects of thyroid uptake blocking agent, Lugol's iodine (Ll) and/or bladder catheterisation (BC). Dose calculations were based on MIRDOSE 3.1 with dynamic bladder model and MIRD Dose Estimate Report No.8 for 99 Tc m -pertechnetate, which has similar biokinetic properties to 188 Re-perrhenate. Normal renal function and a bladder voiding interval of 4.8h (1 minute with catheter) were assumed. BR was simulated ex-vivo by puncturing a Solaris angioplasty balloon filled with normal saline at 4 atm. LI, MAG3 and DTPA substantially reduces the radiation dose following BR, particularly to the thyroid, and BC reduces the bladder wall dose. Only the contents of the balloon leaked; 0.4 ml of the total volume of 1.8ml. As binding of 188 Re to ligands is cumbersome, we opted to use LI. Twenty five patients with in-stent re-stenosis have been treated using 188 Re-perrhenate (8 GBq/ml), with no BR. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  17. Carbon-Based CsPbBr3 Perovskite Solar Cells: All-Ambient Processes and High Thermal Stability.

    Science.gov (United States)

    Chang, Xiaowen; Li, Weiping; Zhu, Liqun; Liu, Huicong; Geng, Huifang; Xiang, Sisi; Liu, Jiaming; Chen, Haining

    2016-12-14

    The device instability has been an important issue for hybrid organic-inorganic halide perovskite solar cells (PSCs). This work intends to address this issue by exploiting inorganic perovskite (CsPbBr 3 ) as light absorber, accompanied by replacing organic hole transport materials (HTM) and the metal electrode with a carbon electrode. All the fabrication processes (including those for CsPbBr 3 and the carbon electrode) in the PSCs are conducted in ambient atmosphere. Through a systematical optimization on the fabrication processes of CsPbBr 3 film, carbon-based PSCs (C-PSCs) obtained the highest power conversion efficiency (PCE) of about 5.0%, a relatively high value for inorganic perovskite-based PSCs. More importantly, after storage for 250 h at 80 °C, only 11.7% loss in PCE is observed for CsPbBr 3 C-PSCs, significantly lower than that for popular CH 3 NH 3 PbI 3 C-PSCs (59.0%) and other reported PSCs, which indicated a promising thermal stability of CsPbBr 3 C-PSCs.

  18. Phase Transitions in CsSnCl3 and CsPbBr3 An NMR and NQR Study

    Science.gov (United States)

    Sharma, Surendra; Weiden, Norbert; Weiss, Alarich

    1991-04-01

    The phase transitions in CsSnCl3 and CsPbBr3 have been studied by X-ray powder diffraction, by 81Br-NQR and by 'H-, 119Sn-, and 113Cs-NMR. At room temperature in air CsSnCl3 forms a hydrate which can be dehydrated to the monoclinic phase II of CsSnCl3. The high temperature phase I has the Perovskite structure, as the X-ray and NMR experiments show. The three phases of CsPbBr3, known from literature, have been corroborated. The results are discussed in the framework of the group ABX3, A = alkalimetal ion, B = IV main group ion, and X = Halogen ion

  19. Facile synthesis and characterization of CsPbBr3 and CsPb2Br5 ...

    Indian Academy of Sciences (India)

    2018-03-23

    Mar 23, 2018 ... All-inorganic caesium lead-halide perovskite CsPbBr3 and ... optoelectronic materials owing to their stabilities and highly efficient photoluminescence (PL). ... chemical tenability [2], hybrid organic–inorganic lead halide-.

  20. Modeling study of vibrational photochemical isotope enrichment. [HBr + Cl/sub 2/; HCl + Br/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Badcock, C.C.; Hwang, W.C.; Kalsch, J.F.

    1978-09-29

    Chemical kinetic modeling studies of vibrational-photochemical isotope enrichment have been performed on two systems: Model (I), H/sup 79/Br(H/sup 81/Br) + Cl/sub 2/ and, Model (II), H/sup 37/Cl(H/sup 35/Cl) + Br. Pulsed laser excitation was modeled to the first excited vibrational level of H/sup 79/Br in Model I and the first and second excited vibrational levels of both HCl isotopes in Model II. These are prototype systems of exoergic (Model I) and endoergic (Model II) reactions. The effects on enrichment of varying the external parameters (pressure, laser intensity) and the internal parameters (rate constants for V-V exchange and excited-state reactions) were examined. Studies of these prototype systems indicate that a favorable reaction for enrichment, with isotopically-specific excitation and a significantly accelerated vibrationally-excited-state reaction should have the following properties: the reaction from v = 0 should be only moderately exoergic, and the most favorable coreactant should be a polyatomic species, such as alkyl radical. Direct excitation of the reacting vibrational level is at least an order of magnitude more favorable for enrichment than is population by energy transfer. Enrichment of the minor isotope by these processes is more effective than is major isotope enrichment. Within limits, increased laser intensity is beneficial. However, for sequential excitation of a second vibrational level, major isotope enrichment can be diminished by high populations of the first vibrational level.

  1. The feasibility of boron containing phosphors in thermal neutron image plates, in particular the systems M sub 2 B sub 5 O sub 9 X : Eu sup 2 sup + (M=Ca, Sr, Ba; X=Cl, Br). Part I: simulation of the energy deposition process

    CERN Document Server

    Knitel, M J; Dorenbos, P; Eijk, C W E; Berezovskaya, I V; Dotsenko, V

    2000-01-01

    A thermal neutron image plate (IP) consisting of a mixture of BaFBr : Eu sup 2 sup + and Gd sub 2 O sub 3 (IP-Gd) is compared with an alternative plate consisting of M sub 2 B sub 5 O sub 9 X : Eu sup 2 sup + (M=Ca, Sr, Ba; X=Cl,Br) (IP-B). In particular, the Detective Quantum Efficiency (DQE) of both plates is considered. Monte Carlo simulations of the energy deposition process after the absorption of a neutron show that the variance of the energy deposition in the IP-Gd affects the DQE to a large extent. Because of this, the average number of photoelectrons detected per incident neutron, , has to be only 1.3 for the haloborates to obtain an IP-B with a higher DQE value than the maximum possible with a IP-Gd.

  2. Comparative genomics of Bacillus anthracis from the wool industry highlights polymorphisms of lineage A.Br.Vollum.

    Science.gov (United States)

    Derzelle, Sylviane; Aguilar-Bultet, Lisandra; Frey, Joachim

    2016-12-01

    With the advent of affordable next-generation sequencing (NGS) technologies, major progress has been made in the understanding of the population structure and evolution of the B. anthracis species. Here we report the use of whole genome sequencing and computer-based comparative analyses to characterize six strains belonging to the A.Br.Vollum lineage. These strains were isolated in Switzerland, in 1981, during iterative cases of anthrax involving workers in a textile plant processing cashmere wool from the Indian subcontinent. We took advantage of the hundreds of currently available B. anthracis genomes in public databases, to investigate the genetic diversity existing within the A.Br.Vollum lineage and to position the six Swiss isolates into the worldwide B. anthracis phylogeny. Thirty additional genomes related to the A.Br.Vollum group were identified by whole-genome single nucleotide polymorphism (SNP) analysis, including two strains forming a new evolutionary branch at the basis of the A.Br.Vollum lineage. This new phylogenetic lineage (termed A.Br.H9401) splits off the branch leading to the A.Br.Vollum group soon after its divergence to the other lineages of the major A clade (i.e. 6 SNPs). The available dataset of A.Br.Vollum genomes were resolved into 2 distinct groups. Isolates from the Swiss wool processing facility clustered together with two strains from Pakistan and one strain of unknown origin isolated from yarn. They were clearly differentiated (69 SNPs) from the twenty-five other A.Br.Vollum strains located on the branch leading to the terminal reference strain A0488 of the lineage. Novel analytic assays specific to these new subgroups were developed for the purpose of rapid molecular epidemiology. Whole genome SNP surveys greatly expand upon our knowledge on the sub-structure of the A.Br.Vollum lineage. Possible origin and route of spread of this lineage worldwide are discussed. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights

  3. Molecular characterization of BrMYB28 and BrMYB29 paralogous transcription factors involved in the regulation of aliphatic glucosinolate profiles in Brassica rapa ssp. pekinensis.

    Science.gov (United States)

    Baskar, Venkidasamy; Park, Se Won

    2015-07-01

    Glucosinolates (GSL) are one of the major secondary metabolites of the Brassicaceae family. In the present study, we aim at characterizing the multiple paralogs of aliphatic GSL regulators, such as BrMYB28 and BrMYB29 genes in Brassica rapa ssp. pekinensis, by quantitative real-time PCR (qRT-PCR) analysis in different tissues and at various developmental stages. An overlapping gene expression pattern between the BrMYBs as well as their downstream genes (DSGs) was found at different developmental stages. Among the BrMYB28 and BrMYB29 paralogous genes, the BrMYB28.3 and BrMYB29.1 genes were dominantly expressed in most of the developmental stages, compared to the other paralogs of the BrMYB genes. Furthermore, the differential expression pattern of the BrMYBs was observed under various stress treatments. Interestingly, BrMYB28.2 showed the least expression in most developmental stages, while its expression was remarkably high in different stress conditions. More specifically, the BrMYB28.2, BrMYB28.3, and BrMYB29.1 genes were highly responsive to various abiotic and biotic stresses, further indicating their possible role in stress tolerance. Moreover, the in silico cis motif analysis in the upstream regulatory regions of BrMYBs showed the presence of various putative stress-specific motifs, which further indicated their responsiveness to biotic and abiotic stresses. These observations suggest that the dominantly expressed BrMYBs, both in different developmental stages and under various stress treatments (BrMYB28.3 and BrMYB29.1), may be potential candidate genes for altering the GSL level through genetic modification studies in B. rapa ssp. pekinensis. Copyright © 2015. Published by Elsevier SAS.

  4. Anomaly observed in Moessbauer spectra near the neel temperature of FeBr sub 2

    CERN Document Server

    Naili Di

    2003-01-01

    In several decades, iron(II) bromide (FeBr sub 2) has been investigated as a typical Ising-type antiferromagnet by several kinds of experimental techniques. By the Moessbauer measurements, it was normally observed that only the magnetic spectrum appeared just below Neel temperature in FeBr sub 2. However, we found the anomalous spectra, in which paramagnetic component coexisted with magnetic one near Neel temperature. For two kinds of single crystal FeBr sub 2 samples, IM and IIM, we determined the Moessbauer parameters of the observed spectra by the computer analyses: the relative absorption intensity I sub p of the paramagnetic component to the total absorption area of the best fitting spectrum and the value of the hyperfine field H sub h sub f of the magnetic component and values of the quadrupole splitting 1/2 centre dot e sup 2 qQ of the magnetic and the paramagnetic components. The temperature variation of H sub h sub f is unique and the same as that observed for the sample in which the anomaly was not ...

  5. Characteristics and performance of thin LaBr3(Ce) crystal for X-ray astronomy

    Science.gov (United States)

    Manchanda, R. K.

    Lanthanum Bromide crystal is the latest among the family of the scintillation counters and has an advantage over conventional room temperature detectors. It has a high atomic number, high light yield, and fast decay time compared to NaI(Tl) crystal and therefore, the energy resolution, of LaBr3 detector is superior and it has higher detection efficiency. In recent past, laboratory studies have been generally made using thick crystal geometry (1.5×1.5-inch and 2×2-inch). Similarly, simulation studies are also in progress for the use of LaBr3 detectors in the ground based high energy physics experiments. The detector background counting rate of LaBr3 crystal is affected by the internal radioactivity and is due to naturally occurring radioisotopes 138La and 227Ac, similar to the sodium Iodide detector which is affected by the iodine isotopes. We have developed a new detector using thin lanthanum bromide crystal (3×30-mm) for use in X-ray astronomy. The instrument was launched in high altitude balloon flight on Dec. 21, 2007, which reached a ceiling altitude of 4.3 mbs. A background counting rate of 1.6 ×10-2 ct cm-2 s-1 keV-1 sr-1 was observed at the ceiling altitude. This paper describes the details of the electronics hardware, energy resolution and the background characteristics of the detector at ceiling altitude

  6. Finding the Missing Stratospheric Br(sub y): A Global Modeling Study of CHBr3 and CH2Br2

    Science.gov (United States)

    Liang, Q.; Stolarski, R. S.; Kawa, S. R.; Nielsen, J. E.; Douglass, A. R.; Rodriguez, J. M.; Blake, D. R.; Atlas, E. L.; Ott, L. E.

    2010-01-01

    Recent in situ and satellite measurements suggest a contribution of 5 pptv to stratospheric inorganic bromine from short-lived bromocarbons. We conduct a modeling study of the two most important short-lived bromocarbons, bromoform (CHBr3) and dibromomethane (CH2Br2), with the Goddard Earth Observing System Chemistry Climate Model (GEOS CCM) to account for this missing stratospheric bromine. We derive a "top-down" emission estimate of CHBr3 and CH2Br2 using airborne measurements in the Pacific and North American troposphere and lower stratosphere obtained during previous NASA aircraft campaigns. Our emission estimate suggests that to reproduce the observed concentrations in the free troposphere, a global oceanic emission of 425 Gg Br yr(exp -1) for CHBr3 and 57 Gg Br yr(exp -l) for CH2Br2 is needed, with 60% of emissions from open ocean and 40% from coastal regions. Although our simple emission scheme assumes no seasonal variations, the model reproduces the observed seasonal variations of the short-lived bromocarbons with high concentrations in winter and low concentrations in summer. This indicates that the seasonality of short-lived bromocarbons is largely due to seasonality in their chemical loss and transport. The inclusion of CHBr3 and CH2Br2 contributes 5 pptv bromine throughout the stratosphere. Both the source gases and inorganic bromine produced from source gas degradation (BrSLS) in the troposphere are transported into the stratosphere, and are equally important. Inorganic bromine accounts for half (2.5 pptv) of the bromine from the inclusion of CHBr3 and CHzBr2 near the tropical tropopause and its contribution rapidly increases to 100% as altitude increases. More than 85% of the wet scavenging of Br(sub y)(sup VSLS) occurs in large-scale precipitation below 500 hPa. Our sensitivity study with wet scavenging in convective updrafts switched off suggests that Br(sub y)(sup SLS) in the stratosphere is not sensitive to convection. Convective scavenging only

  7. Teodicea e Trinità in Bonaventura<br>>Unde ergo habet zizania? i>

    OpenAIRE

    Marco Rossini

    2008-01-01

    Teodicea e relazione. La teologia come garanzia di giustizia nella dialettica tra ordine e libero arbitrio. Teodicy and relationship. The theology as guarantee of justice in the dialectics between order and free will.

  8. I I I I I I

    African Journals Online (AJOL)

    Our findings are in keeping with other reports that VIP levels rise in the portal venous blood in mesenteric ischaemia.6 The mean NT levels in the peripheral venous samp!es in group I showed a decreasing trend, which was also see~ m the por::~ .... portal vein in such a fashion that ;the portal venous blood flow was not ...

  9. Brødbaking for bedre helse

    OpenAIRE

    Brustuen, Anne Mette Slåtsveen

    2016-01-01

    Masteroppgave folkehelsevitenskap - Universitetet i Agder 2016 Introduction: Bread is a part of the Norwegian food culture and a important part of the Norwegian diet. However, the intake of fiber is too low and the health authorities recommend a higher intake of wholemeal bread and cereals. In addition, we throw away as much as 190 000 bread in Norwegian garbage cans every day throughout the year, which is negative in light of the environment. Purpose: This study looks at whether an int...

  10. Aagesta-BR3 Decommissioning Cost. Comparison and Benchmarking Analysis

    International Nuclear Information System (INIS)

    Varley, Geoff

    2002-11-01

    This report presents the results of decommissioning cost analyses focusing on discrete working packages within the decommissioning program of the BR3 reactor in Mol, Belgium and comparison of them with cost estimate data for the Aagesta research reactor in Sweden. The specific BR3 work packages analysed were: Primary coolant piping decontamination; Primary coolant piping dismantling; Vulcain reactor internals dismantling; Westinghouse reactor internals dismantling; Reactor vessel dismantling. The main conclusions to be drawn from the analyses are that: The fixed costs related to decontamination and dismantling activities generally are a very important part of the overall resources needed to execute the work, with the Reactor Pressure Vessel (RPV) seemingly being significantly more demanding than other major components. Cutting activities tend to need something like 150 to 200 labour hours per m 2 of reactor equipment dismantled. Fixed investment costs to set up the equipment needed to cut up major vessels or internals appear to be in the range of MSEK 4 to 8. Consumables costs vary according to the nature of the equipment being dismantled. The thicker the metal being cut, the higher the attrition rate for things such as cutting blades. The range of consumables costs at BR3 have been in the range of MSEK 0.1 to 0.2/m 2 dismantled. The extent of detailed information available in the 1996 Aagesta estimate is not sufficient to enable a full comparison with the BR3 decommissioning results. A global first comparison has been attempted by summing the resources expended on the BR3 work packages described in this report with the combined dismantling data presented in the 1996 Aagesta cost estimate report. Very broadly the cost of decontamination plus dismantling of the main process equipment at Aagesta appears to be in the order of MSEK 70, of which MSEK 4 is labour on preparatory/planning work, MSEK 40 is labour on actual decontamination and dismantling and MSEK 25 is

  11. Zn2(TeO3)Br2

    Science.gov (United States)

    Zhang, Dong; Johnsson, Mats

    2008-01-01

    Single crystals of dizinc tellurium dibromide trioxide, Zn2(TeO3)Br2, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound has a layered crystal structure in which the building units are [ZnO4Br] distorted square pyramids, [ZnO2Br2] distorted tetra­hedra, and [TeO3 E] tetra­hedra (E being the 5s 2 lone pair of Te4+) joined through sharing of edges and corners to form layers of no net charge. Bromine atoms and tellurium lone pairs protrude from the surfaces of each layer towards adjacent layers. This new compound Zn2(TeO3)Br2 is isostructural with the synthetic compounds Zn2(TeO3)Cl2, CuZn(TeO3)2, Co2(TeO3)Br2 and the mineral sophiite, Zn2(SeO3)Cl2. PMID:21202162

  12. Photoelectron Emission Studies in CsBr at 257 nm

    International Nuclear Information System (INIS)

    Maldonado, Juan R.; Liu, Zhi; Sun, Yun; Pianetta, Piero A.; Pease, Fabian W.

    2006-01-01

    CsBr/Cr photocathodes were found [1,2] to meet the requirements of a multi-electron beam lithography system operating with a light energy of 4.8 eV (257nm). The fact that photoemission was observed with a light energy below the reported 7.3 eV band gap for CsBr was not understood. This paper presents experimental results on the presence of intra-band gap absorption sites (IBAS) in CsBr thin film photo electron emitters, and presents a model based on IBAS to explain the observed photoelectron emission behavior at energies below band gap. A fluorescence band centered at 330 nm with a FWHM of about 0.34 eV was observed in CsBr/Cr samples under 257 nm laser illumination which can be attributed to IBAS and agrees well with previously obtained synchrotron photoelectron spectra[1] from the valence band of CsBr films

  13. Field-effect transistors with high mobility and small hysteresis of transfer characteristics based on CH3NH3PbBr3 films

    Science.gov (United States)

    Aleshin, A. N.; Shcherbakov, I. P.; Trapeznikova, I. N.; Petrov, V. N.

    2017-12-01

    Field-effect transistor (FET) structures based on soluble organometallic perovskites, CH3NH3PbBr3, were obtained and their electrical properties were studied. FETs made of CH3NH3PbBr3 films possess current- voltage characteristics (IVs) typical for ambipolar FETs with saturation regime. The transfer characteristics of FETs based on CH3NH3PbBr3 have an insignificant hysteresis and slightly depend on voltage at the source-drain. Mobilities of charge carriers (holes) calculated from IVs of FETs based on CH3NH3PbBr3 at 300 K in saturation and weak field regimes were 5 and 2 cm2/V s, respectively, whereas electron mobility is 3 cm2/V s, which exceeds the mobility value 1 cm2/V s obtained earlier for FETs based on CH3NH3PbI3.

  14. Imbedded Nanocrystals of CsPbBr3 in Cs4 PbBr6 : Kinetics, Enhanced Oscillator Strength, and Application in Light-Emitting Diodes.

    Science.gov (United States)

    Xu, Junwei; Huang, Wenxiao; Li, Peiyun; Onken, Drew R; Dun, Chaochao; Guo, Yang; Ucer, Kamil B; Lu, Chang; Wang, Hongzhi; Geyer, Scott M; Williams, Richard T; Carroll, David L

    2017-11-01

    Solution-grown films of CsPbBr 3 nanocrystals imbedded in Cs 4 PbBr 6 are incorporated as the recombination layer in light-emitting diode (LED) structures. The kinetics at high carrier density of pure (extended) CsPbBr 3 and the nanoinclusion composite are measured and analyzed, indicating second-order kinetics in extended and mainly first-order kinetics in the confined CsPbBr 3 , respectively. Analysis of absorption strength of this all-perovskite, all-inorganic imbedded nanocrystal composite relative to pure CsPbBr 3 indicates enhanced oscillator strength consistent with earlier published attribution of the sub-nanosecond exciton radiative lifetime in nanoprecipitates of CsPbBr 3 in melt-grown CsBr host crystals and CsPbBr 3 evaporated films. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Una nueva <i>Armeria> del Sistema Central (España: <i>A. rivasmartineziii> (Plumbaginaceae

    Directory of Open Access Journals (Sweden)

    Sardinero, Santiago

    1997-12-01

    Full Text Available A new taxon from the central-western Sistema Central (Sierra de Béjar and Sierra de Tormantos, Spain, <i>Armeria rivasmartineziii>. is described and illustrated. lts morphological affinities and variability are discussed in concordance with its hypothetical hybrid origin.<br>>Se describe e ilustra un nuevo taxon del centro-occidente del Sistema Central español. <i>Armeria rivasmartineziii>. Se discuten sus afinidades morfológicas y variabilidad en concordancia con su hipotético origen híbrido.

  16. Trapping molecular bromine: a one-dimensional bromobismuthate complex with Br2 as a linker.

    Science.gov (United States)

    Adonin, S A; Gorokh, I D; Abramov, P A; Plyusnin, P E; Sokolov, M N; Fedin, V P

    2016-03-07

    The reaction between solid (NMP)n{[BiBr4]}n (1) (NMP = N-methylpyridinium) and Br2, generated in situ in HBr solution, results in the formation of (NMP)3[Bi2Br9]·Br2 (2). In the structure of 2, dibromine molecules connect discrete binuclear [Bi2Br9](3-) anions into an extended network. Complex 2 is thermally stable (up to 150 °C).

  17. Void distributions in liquid BiBr{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, K [Faculty of Science, Niigata University, Niigata 950-2181 (Japan); Endo, H [Faculty of Science, Kyoto University, Kyoto 606-8224 (Japan); Hoshino, H [Faculty of Education, Hirosaki University, Hirosaki 036-8560 (Japan); Kawakita, Y [Faculty of Sciences, Kyushu University, Fukuoka 810-8560 (Japan); Kohara, S; Itou, M [Japan Synchrotron Radiation Research Institute(JASRI), Sayo-cho 679-5198 (Japan)

    2008-02-15

    The X-ray diffraction experiments and the reverse Monte Carlo analysis for liquid BiBr{sub 3} have been performed to clarify the distribution of Bi and Br ions around voids, comparing with previous results derived in the neutron diffraction experiments. The hexagonal cages involving voids are formed by the corner-sharing of the trigonal pyramidal BiBr{sub 3} blocks. The neighboring cages are linked together in highly correlated fashion. The observed pre-peak in S(Q) at 1.3A{sup -1} is related to the pre-peak of the void-based S'{sub CC} (Q) due to an intermediate chemical order in the structure. The pre-peak intensity increases with increasing temperature. This characteristic change for the pre-peak intensity is discussed by considering the modifications of the topology and stacking in the hexagonal cages.

  18. Production and evaluation of cytotoxic effects of DT386-BR2 fusion protein as a novel anti-cancer agent.

    Science.gov (United States)

    Shafiee, Fatemeh; Rabbani, Mohammad; Jahanian-Najafabadi, Ali

    2016-11-01

    The aim of this study was to produce a fusion protein consisting of the catalytic and translocation domains of diphtheria toxin fused to BR2, a cancer specific cell penetrating peptide, and evaluation of its cytotoxic effects for targeted eradication of cancer cells. For this purpose, The DT386-BR2 structure was predicted using Modeller 9.14 and the best predicted model was selected based on the minimum DOPE score. A synthetic gene encoding DT386-BR2 was cloned in pET28a expression vector, expressed and purified by affinity chromatography. SDS-PAGE and Western blotting confirmed the expression of the DT386-BR2 fusion protein by revealing a band of about 47kDa after the induction of the expression. Finally, the purified protein was subjected to MTT assay for evaluation of its cyto-lethal effects on cancer and normal cell lines. Statistical analysis showed significant reduction in survival percent of HeLa and MCF-7 cancer cells in comparison to negative control (PBS), while the cytotoxic effect was not significant on the normal cells, i.e. HUVEC and HEK 293. The IC50 of DT386-BR2 for HeLa and MCF-7 was about 0.55 and 2.08μg/ml, respectively. In conclusion, the production and purification of DT386-BR2 fusion protein was successfully achieved and its cytotoxic effects on the studied cancer cell lines was established. The promising cytotoxic effects of this newly constructed fusion protein made it a suitable candidate for targeted therapy of cancer, and further in vitro and in vivo studies on this fusion protein is underway. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Balloon-borne stratospheric BrO measurements: comparison with Envisat/SCIAMACHY BrO limb profiles

    Directory of Open Access Journals (Sweden)

    M. Dorf

    2006-01-01

    Full Text Available For the first time, results of four stratospheric BrO profiling instruments, are presented and compared with reference to the SLIMCAT 3-dimensional chemical transport model (3-D CTM. Model calculations are used to infer a BrO profile validation set, measured by 3 different balloon sensors, for the new Envisat/SCIAMACHY (ENVIronment SATellite/SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY satellite instrument. The balloon observations include (a balloon-borne in situ resonance fluorescence detection of BrO (Triple, (b balloon-borne solar occultation DOAS measurements (Differential Optical Absorption Spectroscopy of BrO in the UV, and (c BrO profiling from the solar occultation SAOZ (Systeme d'Analyse par Observation Zenithale balloon instrument. Since stratospheric BrO is subject to considerable diurnal variation and none of the measurements are performed close enough in time and space for a direct comparison, all balloon observations are considered with reference to outputs from the 3-D CTM. The referencing is performed by forward and backward air mass trajectory calculations to match the balloon with the satellite observations. The diurnal variation of BrO is considered by 1-D photochemical model calculation along the trajectories. The 1-D photochemical model is initialised with output data of the 3-D model with additional constraints on the vertical transport, the total amount and photochemistry of stratospheric bromine as given by the various balloon observations. Total [Bry]=(20.1±2.5 pptv obtained from DOAS BrO observations at mid-latitudes in 2003, serves as an upper limit of the comparison. Most of the balloon observations agree with the photochemical model predictions within their given error estimates. First retrieval exercises of BrO limb profiling from the SCIAMACHY satellite instrument on average agree to around 20% with the photochemically-corrected balloon observations of the remote sensing instruments (SAOZ

  20. All-Ambient Processed Binary CsPbBr3-CsPb2Br5 Perovskites with Synergistic Enhancement for High-Efficiency Cs-Pb-Br-Based Solar Cells.

    Science.gov (United States)

    Zhang, Xisheng; Jin, Zhiwen; Zhang, Jingru; Bai, Dongliang; Bian, Hui; Wang, Kang; Sun, Jie; Wang, Qian; Liu, Shengzhong Frank

    2018-02-28

    All-inorganic CsPbBr 3 perovskite solar cells display outstanding stability toward moisture, light soaking, and thermal stressing, demonstrating great potential in tandem solar cells and toward commercialization. Unfortunately, it is still challenging to prepare high-performance CsPbBr 3 films at moderate temperatures. Herein, a uniform, compact CsPbBr 3 film was fabricated using its quantum dot (QD)-based ink precursor. The film was then treated using thiocyanate ethyl acetate (EA) solution in all-ambient conditions to produce a superior CsPbBr 3 -CsPb 2 Br 5 composite film with a larger grain size and minimal defects. The achievement was attributed to the surface dissolution and recrystallization of the existing SCN - and EA. More specifically, the SCN - ions were first absorbed on the Pb atoms, leading to the dissolution and stripping of Cs + and Br - ions from the CsPbBr 3 QDs. On the other hand, the EA solution enhances the diffusion dynamics of surface atoms and the surfactant species. It is found that a small amount of CsPb 2 Br 5 in the composite film gives the best surface passivation, while the Br-rich surface decreases Br vacancies (V Br ) for a prolonged carrier lifetime. As a result, the fabricated device gives a higher solar cell efficiency of 6.81% with an outstanding long-term stability.

  1. Polymorphism in 2-X-adamantane derivatives (X = Cl, Br).

    Science.gov (United States)

    Negrier, Philippe; Barrio, María; Tamarit, Josep Ll; Mondieig, Denise

    2014-08-14

    The polymorphism of two 2-X-adamantane derivatives, X = Cl, X = Br, has been studied by X-ray powder diffraction and normal- and high-pressure (up to 300 MPa) differential scanning calorimetry. 2-Br-adamantane displays a low-temperature orthorhombic phase (space group P212121, Z = 4) and a high-temperature plastic phase (Fm3̅m, Z = 4) from 277.9 ± 1.0 K to the melting point at 413.4 ± 1.0 K. 2-Cl-adamantane presents a richer polymorphic behavior through the temperature range studied. At low temperature it displays a triclinic phase (P1̅, Z = 2), which transforms to a monoclinic phase (C2/c, Z = 8) at 224.4 ± 1.0 K, both phases being ordered. Two high-temperature orientationally disordered are found for this compound, one hexagonal (P63/mcm, Z = 6) at ca. 241 K and the highest one, cubic (Fm3̅m, Z = 4), being stable from 244 ± 1.0 K up to the melting point at 467.5 ± 1.0 K. No additional phase appears due to the increase in pressure within the studied range. The intermolecular interactions are found to be weak, especially for the 2-Br-adamantane compound for which the Br···Br as well as C-Br···H distances are larger than the addition of the van der Waals radii, thus confirming the availability of this compound for building up diamondoid blocks.

  2. Extended analysis of fifth spectrum of bromine: Br V

    International Nuclear Information System (INIS)

    Riyaz, A.; Tauheed, A.; Rahimullah, K.

    2014-01-01

    The fifth spectrum of bromine (Br V) has been studied in the 200–2400 Å wavelength region. The spectrum was photographed on a 3-m normal incidence vacuum spectrograph at the St. Francis Xavier University, Antigonish (Canada) and 6.65-m grazing incidence spectrograph at the Zeeman laboratory (Amsterdam). The light sources used were a triggered spark and sliding spark. The ground configuration of Br V is 4s 2 4p. The excited configurations 4s4p 2 +4s 2 (4d+5d+5s+6s+7s+5g+6g)+4s4p(5p+4f)+4p 2 4d in the even parity system and the 4p 3 +4s 2 (5p+6p+7p+4f)+4s4p4d+4s4p5s configurations in the odd parity system have been studied. Relativistic Hartree–Fock (HFR) and least squares fitted (LSF) parametric calculations have been used to interpret the observed spectrum. 99 levels of Br V have now been established, 43 being new. Among 394 classified spectral lines, 181 are newly classified. The level 4s 2 7s 2 S 1/2 is revised. We estimate the accuracy of our measured wavelengths for sharp and unblended lines to be±0.005 Å. The ionization limit is determined as 479,657±200 cm −1 (59.470±0.025 eV). - Highlights: • The spectrum of Br was recorded on a 3-m spectrograph with triggered spark source. • Atomic transitions for Br V were identified to established new energy levels. • CI calculations with relativistic corrections were made for theoretical predictions. • Weighted oscillator strength (gf) and transition probabilities (gA) were calculated. • Ionization potential of Br V was determined experimentally

  3. Genomic identification and characterization of the elite strains Bradyrhizobium yuanmingense BR 3267 and Bradyrhizobium pachyrhizi BR 3262 recommended for cowpea inoculation in Brazil.

    Science.gov (United States)

    Leite, Jakson; Passos, Samuel Ribeiro; Simões-Araújo, Jean Luiz; Rumjanek, Norma Gouvêa; Xavier, Gustavo Ribeiro; Zilli, Jerri Édson

    2017-03-31

    The leguminous inoculation with nodule-inducing bacteria that perform biological nitrogen fixation is a good example of an "eco-friendly agricultural practice". Bradyrhizobium strains BR 3267 and BR 3262 are recommended for cowpea (Vigna unguiculata) inoculation in Brazil and showed remarkable responses; nevertheless neither strain was characterized at species level, which is our goal in the present work using a polyphasic approach. The strains presented the typical phenotype of Bradyrhizobium with a slow growth and a white colony on yeast extract-mannitol medium. Strain BR 3267 was more versatile in its use of carbon sources compared to BR 3262. The fatty acid composition of BR 3267 was similar to the type strain of Bradyrhizobium yuanmingense; while BR 3262 was similar to Bradyrhizobium elkanii and Bradyrhizobium pachyrhizi. Phylogenetic analyses based on 16S rRNA and three housekeeping genes placed both strains within the genus Bradyrhizobium: strain BR 3267 was closest to B. yuanmingense and BR 3262 to B. pachyrhizi. Genome average nucleotide identity and DNA-DNA reassociation confirmed the genomic identification of B. yuanmingense BR 3267 and B. pachyrhizi BR 3262. The nodC and nifH gene analyses showed that strains BR 3267 and BR 3262 hold divergent symbiotic genes. In summary, the results indicate that cowpea can establish effective symbiosis with divergent bradyrhizobia isolated from Brazilian soils. Published by Elsevier Editora Ltda.

  4. Skandaalin vaikutus brändin imagoon - Case Audi

    OpenAIRE

    Puntalo, Ville-Veikko

    2016-01-01

    Opinnäytetyössä tutkittiin Volkswagenin päästöhuijausskandaalin vaikutusta Audi-brändin imagoon. Tutkimuksessa pyrittiin selvittämään onko ennakoitavissa mahdollisia myyntitulosten muutoksia ja johtuivatko ne kyseisestä skandaalista. Opinnäytetyön teoriaosuudessa perehdyttiin ostokäyttäytymisen prosessiin, brändin rakentumiseen, positiivisen maineen saavuttamiseen ja tunnettuihin yritysmaailman skandaaleihin. Lisäksi käytiin läpi Volkswagen päästöskandaalin taustaa sekä sen seurauksia. ...

  5. Ageing management of the BR2 research reactor

    International Nuclear Information System (INIS)

    Verpoortem, J. R.; Van Dyck, S.

    2014-01-01

    At the Belgian nuclear research centre (SCK.CEN) several test reactors are operated. Among these, Belgian Reactor 2 (BR2) is the largest Material Test Reactor (MTR). This water-cooled, beryllium moderated reactor with a maximum thermal power of 100 MW became operational in 1962. Except for two major refurbishment campaigns of one year each, this reactor has been operated continuously over the past 50 years, with a frequency of 5-12 cycles per year. At present, BR2 is used for different research activities, the production of medical isotopes, the production of n-doped silicon and various training and education activities. (Author)

  6. MM-rallin vaikutus Toyotan brändiin

    OpenAIRE

    Laurila, Heini

    2017-01-01

    Tämän insinöörityön tarkoituksena oli selvittää, millainen vaikutus MM-ralliin palaamisella on Toyotan brändiin Suomessa. Insinöörityö toteutettiin yhteistyössä Suomen Toyotan ja Lexuksen maahantuojayrityksen, Toyota Auto Finland Oy:n sekä AKK Sports Oy:n kanssa. AKK Sports Oy on vastuussa vuosittaisen Suomen MM-ralliosakilpailun, Neste Rallin, järjestämisestä. Tutkimuksen taustatyönä tutustuttiin ensin brändejä ja markkinointia koskevaan kirjallisuuteen. Sen lisäksi käytiin läpi Toyotan ...

  7. The model of recombination process in TlBr

    International Nuclear Information System (INIS)

    Grigorjeva, L.; Millers, D.

    2002-01-01

    The time-resolved luminescence was used as a tool in the study of recombination process in several undoped TlBr crystals. The spectra and decay kinetics observed under electron beam excitation were investigated. Observation of several luminescence bands with different decay rates shows that more than one recombination center is involved and the recombination process is quite complicated. The band at ∼2.5 eV is dominant under 10 ns excitation pulse (electron beam or nitrogen laser pulses). The results of short-lived absorption and luminescence are used for analysis of possible mechanisms of recombination processes in TlBr

  8. Stratospheric BrONO2 observed by MIPAS

    Directory of Open Access Journals (Sweden)

    H. Fischer

    2009-03-01

    Full Text Available The first measurements of stratospheric bromine nitrate (BrONO2 are reported. Bromine nitrate has been clearly identified in atmospheric infrared emission spectra recorded with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS aboard the European Envisat satellite, and stratospheric concentration profiles have been determined for different conditions (day and night, different latitudes. The BrONO2 concentrations show strong day/night variations, with much lower concentrations during the day. Maximum volume mixing ratios observed during night are 20 to 25 pptv. The observed concentration profiles are in agreement with estimations from photochemical models and show that the current understanding of stratospheric bromine chemistry is generally correct.

  9. Evaluation of (o)-[77Br]bromohippuran as renal tubular function agent

    International Nuclear Information System (INIS)

    Aswegen, A. van; Roodt, J.P.; Pieters, H.; Herbst, C.P.; Otto, A.C.; Loetter, M.G.; Minnaar, P.C.; Haasbroek, F.J.

    1985-01-01

    (o)-[ 77 Br]bromohippuran (BHIP) was developed as renal tubular function agent due to its favourable chemical and physical properties and compared to (o)-[ 131 I]iodohippuran (IHIP). Renograms obtained from baboons were compared and absorbed radiation dose calculations performed. Although BHIP showed a delayed kidney uptake and washout pattern, good kidney clearance of the radionuclide was obtained after 30 min. Radiation dose values for BHIP were markedly lower than for IHIP indicating that larger activities of BHIP could be administered to increase counting statistics. BHIP imaging in normal volunteers did however not substantiate the favourable behaviour obtained in the primate. (author)

  10. Extended fine structure in the K-shell photoionization spectrum of Br2

    International Nuclear Information System (INIS)

    Dill, D.; Dehmer, J.L.

    1975-01-01

    The multiple-scattering approach to molecular wavefunctions in the electronic continuum has been used recently to elucidate the structure of the shape resonance just above threshold in the K-shell photoionization spectrum of N 2 . A similar calculation for Br 2 has yielded significantly different results, i.e., there is no shape resonance; appearing instead is a single resonance in the discrete spectrum, and the photoionization spectrum is found to oscillate with appreciable amplitude throughout the spectral range investigated, from threshold to 60 Ry

  11. Synthesis and crystal structure of Cd2SbBr2

    International Nuclear Information System (INIS)

    Reshetova, L.N.; Shevel'kov, A.V.; Popovkin, B.A.

    1999-01-01

    A new cadmium antimonidobromide, i.e. Cd 2 SbBr 2 , has been synthesized by the standard ampoule method. The compound is crystallized in monoclinic system of sp. gr. P2 1 :a=8.244 (1), b=9.920(1), c=8.492(1) A, Β=116.80(1) deg. Binuclear anions of Sb 2 4- (Sb-Sb 2.78 A), octahedrically surrounded by six cadmium atoms, are a basic specific feature of the structure. Octahedrons of Sb 2 Cd 6 , by collectivizing the equatorial vertices. form layers, the alternation mode of which is similar to the one described for cadmium and mercury arsenidochlorides

  12. Study of water flowrate using time transient and cross-correlation techniques with 82Br radiotracer

    International Nuclear Information System (INIS)

    Salgado, William L.; Brandao, Luiz E.B.

    2013-01-01

    This paper aims to determinate the water flowrate using Time Transient and Cross-Correlation techniques. The detection system uses two NaI (T1) detectors adequately positioned on the outside of pipe and a gamma-ray source ( 82 Br radiotracer). The water flowrate measurements using Time Transient and Cross-Correlation techniques were compared to invasive conventional measurements of the flowrate previously installed in pipeline. Discrepancies between Time Transient and Cross-Correlation techniques flowmeter previously installed in pipeline. Discrepancies between Time Transient and Cross-Correlation techniques flowrate values were found to be less than 3% in relation to conventional ones. (author)

  13. Caryological notes in some portuguese <i>Ranunculaceae>

    Directory of Open Access Journals (Sweden)

    Queirós, Margarida

    1990-05-01

    Full Text Available Chromosome numbers of fourteen portuguese laxa of <i>Ranunculaceae> are reported: <i>Helleborus foetidusi> 20 = 32; <i>Nigella damascenai> 2n = 12; <i>N. gallicai> 2n = 12; <i>Delphinium Pentagynumi> 2n = 16; <i>D. Halteratumi> subsp. <i>verdunense> 2n = 16; <i>Anemone palmetai> 2n = 32; <i>Clematis campaniflorai> 2n = 16; <i>Ranunculus muricatusi> 2n = 48; <i>R. repensi> 2n = 32; <i>R. bulbosusi> subsp. <i>aleae> var. <i>adscendens> 2n =16; <i>R. sceleratusi> 2n = 32; <i>R. paludosusi> 2n = 32; <i>R. nigrescensi> 2n = 16; <i>Aquilegia vulgarisi> subsp. <i>dichroa> 2n = 14. The chromosome numbers are in accordance with previous results.<br>>Se estudia el número cromosómico de algunos táxones de <i>Ranunculaceae> portugueses: <i>Helleborus foetidusi> 2n = 32; <i>Nigella damascenai> 2n = 12; <i>N. gallicai> 2n = 12; <i>Delphinium Pentagynumi> 2n = 16; <i>D. Halteratumi> subsp. <i>verdunense> 2n = 16; <i>Anemone palmetai> 2n = 32; <i>Clematis campaniflorai> 2n = 16; <i>Ranunculus muricatusi> 2n = 48; <i>R. repensi> 2n = 32; <i>R. bulbosusi> subsp. <i>aleae> var. <i>adscendens> 2n =16; <i>R. sceleratusi> 2n = 32; <i>R. paludosusi> 2n = 32; <i>R. nigrescensi> 2n = 16; <i>Aquilegia vulgarisi> subsp. <i>dichroa> 2n = 14. Estos recuentos coinciden con los obtenidos anteriormente por otros autores.

  14. Reactions of N2O5 with Salty and Surfactant-Coated Glycerol: Interfacial Conversion of Br- to Br2 Mediated by Alkylammonium Cations.

    Science.gov (United States)

    Shaloski, Michael A; Gord, Joseph R; Staudt, Sean; Quinn, Sarah L; Bertram, Timothy H; Nathanson, Gilbert M

    2017-05-18

    Gas-liquid scattering and product-yield experiments are used to investigate reactions of N 2 O 5 with glycerol containing Br - and surfactant ions. N 2 O 5 oxidizes Br - to Br 2 for every solution tested: 2.7 M NaBr, 0.03 M tetrahexylammonium bromide (THABr), 0.03 M THABr + 0.5 M NaBr, 0.03 M THABr + 0.5 M NaCl, 0.03 M THABr + 0.01 M sodium dodecyl sulfate (SDS), and 0.01 M cetyltrimethylammonium bromide (CTABr). N 2 O 5 also reacts with glycerol itself to produce mono- and dinitroglycerin. Surface tension measurements indicate that 0.03 M THABr and 2.7 M NaBr have similar interfacial Br - concentrations, though their bulk Br - concentrations differ by 90-fold. We find that twice as much Br 2 is produced in the presence of THA + , implying that the conversion of Br - to Br 2 is initiated at the interface, perhaps mediated by the charged, hydrophobic pocket within the surface THA + cation. The addition of 0.5 M NaBr, 0.5 M NaCl, or 0.01 M SDS to 0.03 M THABr lowers the Br 2 production rate by 23%, 63%, and 67% of the THABr value, respectively. When CTA + is substituted for THA + , Br 2 production drops to 12% of the THABr value. The generation of Br 2 under such different conditions implies that trace amounts of surface-active alkylammonium ions can catalyze interfacial N 2 O 5 reactions, even when salts and other surfactants are present.

  15. Aagesta-BR3 Decommissioning Cost. Comparison and Benchmarking Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Varley, Geoff [NAC International, Henley on Thames (United Kingdom)

    2002-11-01

    This report presents the results of decommissioning cost analyses focusing on discrete working packages within the decommissioning program of the BR3 reactor in Mol, Belgium and comparison of them with cost estimate data for the Aagesta research reactor in Sweden. The specific BR3 work packages analysed were: Primary coolant piping decontamination; Primary coolant piping dismantling; Vulcain reactor internals dismantling; Westinghouse reactor internals dismantling; Reactor vessel dismantling. The main conclusions to be drawn from the analyses are that: The fixed costs related to decontamination and dismantling activities generally are a very important part of the overall resources needed to execute the work, with the Reactor Pressure Vessel (RPV) seemingly being significantly more demanding than other major components. Cutting activities tend to need something like 150 to 200 labour hours per m{sup 2} of reactor equipment dismantled. Fixed investment costs to set up the equipment needed to cut up major vessels or internals appear to be in the range of MSEK 4 to 8. Consumables costs vary according to the nature of the equipment being dismantled. The thicker the metal being cut, the higher the attrition rate for things such as cutting blades. The range of consumables costs at BR3 have been in the range of MSEK 0.1 to 0.2/m{sup 2} dismantled. The extent of detailed information available in the 1996 Aagesta estimate is not sufficient to enable a full comparison with the BR3 decommissioning results. A global first comparison has been attempted by summing the resources expended on the BR3 work packages described in this report with the combined dismantling data presented in the 1996 Aagesta cost estimate report. Very broadly the cost of decontamination plus dismantling of the main process equipment at Aagesta appears to be in the order of MSEK 70, of which MSEK 4 is labour on preparatory/planning work, MSEK 40 is labour on actual decontamination and dismantling and MSEK

  16. Interaction mechanisms of ionic liquids [Cnmim]Br (n=4, 6, 8, 10) with bovine serum albumin

    International Nuclear Information System (INIS)

    Yan Hua; Wu Junyong; Dai Guoliang; Zhong Aiguo; Chen Hao; Yang Jianguo; Han Deman

    2012-01-01

    It is important to study the interaction of ionic liquids (ILs) with protein for the applications of ILs in biochemical process, and help the researchers to choose and design the better ILs to serve as a solvent. In this work, the interaction between 1-alkyl-3-methylimidazolium bromide [C n mim]Br (n=4, 6, 8, 10) and bovine serum albumin (BSA) was systematically investigated for the first time by multi-spectroscopic approach (fluorescence, UV–vis and FT-IR spectroscopy) and density functional theory (DFT). [C n mim]Br (n=4, 6, 8, 10) can bind to BSA by H-bond interaction between their cationic headgroups and Asp/Glu amino acid residue at the surface of BSA, and hydrophobic interaction between their hydrocarbon chains and the hydrophobic amino acid residues in the interior of BSA. On the basis of thermodynamic parameters and the similar structure of [C n mim]Br (n=4, 6, 8, 10), it can be inferred that the hydrophobic interaction plays a major role in the interaction of [C 10 mim]Br with BSA, while the hydrogen bond and van der Waals force play a major role in the interaction of [C n mim]Br (n=4, 6, 8) with BSA. Synchronous fluorescence and FT-IR spectra indicate that [C 10 mim]Br could markedly change the secondary structure of BSA, while [C n mim]Br (n=4, 6, 8) could slightly change the secondary structure of BSA. The results allowed us to understand (i) the effect of the alkyl chain length of the cation on the mechanism of ILs–protein interaction and (ii) the effect of the alkyl chain length of the cation on the protein secondary structure. - Highlights: ► Interaction of [C n mim]Br with BSA was investigated by spectroscopy and DFT. ► Interaction mechanisms and BSA secondary structure were discussed. ► Effects of the alkyl chain length of cation were presented.

  17. On five <i>Compositae> taxa which are confusingly illustrated in fl oristic publications for Andorra

    Directory of Open Access Journals (Sweden)

    Von Raab-Straube, E.

    2009-12-01

    Full Text Available Five <i>Compositae> taxa which are illustrated in floristic publications for Andorra are questionable records which appear to have never been collected there in the wild.<br>>Se comentan cinco taxones de compuestas que aparecen confusamente ilustrados en publicaciones florísticas de Andorra y que nunca se han recolectado en territorio andorrano.

  18. Elastic properties of Cs2HgBr4 and Cs2CdBr4 crystals

    International Nuclear Information System (INIS)

    Kityk, A.V.; Zadorozhna, A.V.; Shchur, Y.I.; Martynyuk-Lototska, Y.I.; Burak, Y.; Vlokh, O.G.

    1998-01-01

    Using ultrasonic velocity measurements, all components of the elastic constant matrix C ij , elastic compliances matrix S ij , and linear compressibility constants matrix K ij of orthorhombic Cs 2 HgBr 4 and Cs 2 CdBr 4 crystals have been determined over a wide temperature range, including the region of the phase transition from the normal to the incommensurate phase. Results obtained are considered within the framework of the phenomenological theory. Preliminary analysis of the acoustical properties at room temperature clearly indicates that both crystals are relatively important materials for acousto-optical applications. Copyright (1998) CSIRO Australia

  19. Constraints on an effective Lagrangian from the combined $H\\to ZZ^*\\to 4\\ell$ and $H\\to\\gamma\\gamma$ channels using 36.1 fb$^{-1}$ of $\\sqrt{s}=$ 13 TeV $pp$ collision data collected with the ATLAS detector

    CERN Document Server

    The ATLAS collaboration

    2017-01-01

    Six parameters of an effective field theory are constrained using the combined $H\\to\\gamma\\gamma$ and $H\\to ZZ^*\\to 4\\ell$ channels, based on 36.1 fb$^{-1}$ of proton-proton collision data collected by the ATLAS experiment at the LHC at $\\sqrt{s}=$ 13 TeV. The parameters are sensitive to modifications of the Higgs boson couplings to strong and electroweak gauge bosons, and to the top quark. The most stringent constraints are those on the effective couplings to photons and to gluons.

  20. Steering dissociation of Br2 molecules with two femtosecond pulses via wave packet interference.

    Science.gov (United States)

    Han, Yong-Chang; Yuan, Kai-Jun; Hu, Wen-Hui; Yan, Tian-Min; Cong, Shu-Lin

    2008-04-07

    The dissociation dynamics of Br2 molecules induced by two femtosecond pump pulses are studied based on the calculation of time-dependent quantum wave packet. Perpendicular transition from X 1Sigma g+ to A 3Pi 1u+ and 1Pi 1u+ and parallel transition from X 1Sigma g+ to B 3Pi 0u+, involving two product channels Br (2P3/2)+Br (2P3/2) and Br (2P3/2)+Br* (2P1/2), respectively, are taken into account. Two pump pulses create dissociating wave packets interfering with each other. By varying laser parameters, the interference of dissociating wave packets can be controlled, and the dissociation probabilities of Br2 molecules on the three excited states can be changed to different degrees. The branching ratio of Br*/(Br+Br*) is calculated as a function of pulse delay time and phase difference.

  1. Analytical potential energy function for the Br + H2 system

    International Nuclear Information System (INIS)

    Kurosaki, Yuzuru

    2001-01-01

    Analytical functions with a many-body expansion for the ground and first-excited-state potential energy surfaces for the Br+H 2 system are newly presented in this work. These functions describe the abstraction and exchange reactions qualitatively well, although it has been found that the function for the ground-state potential surface is still quantitatively unsatisfactory. (author)

  2. Reactivity effects due to beryllium poisoning of BR2

    International Nuclear Information System (INIS)

    Kalcheva, S.; Ponsard, B.; Koonen, E.

    2004-01-01

    This paper illustrates the impact of the poisoning of the beryllium reflector on reactivity variations of the Belgian MTR BR2 in SCK.CEN. Detailed calculations by MCNP-4C of reactivity effects caused by strong neutron absorbers 3 He and 6 Li during reactor operation history are presented. The importance of beryllium poisoning for the accuracy of reactivity predictions is discussed. (authors)

  3. Redetermination of the Crystal Structure of Al2Br6

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Poulsen, Finn W.; Nielsen, Kurt

    1997-01-01

    . In accordance with previous results, the structure belongs to the monoclinic space group P2(1)/a, no. 14, C-2h(5), with a = 10.301(4), b = 7.095(2), c = 7.525(3) Angstrom, and beta = 96.44(3)degrees, and with two Al2Br6 molecules per unit cell. The single crystal was refined to R = 0.0746. Rather similar......The structure of aluminium bromide has been reinvestigated by X-ray diffraction in three different ways: (a) on a single crystal grown in a glass capillary, (b) on powder in a Debye-Scherrer glass capillary and (c) on an area of powder placed in a protective container for Bragg-Brentano geometry...... structural results were obtained from full-profile Rietveld refinements of powder data [goodness of fit = 1.38 and 2.54 for (b) and (c), respectively]. The Al2Br6 molecule consists of two edge-sharing, almost regular AlBr4 tetrahedra. The Al-Br bond distances are in the range 2.21-2.42 Angstrom...

  4. Narva kant vajab oma brändi / Esko Passila

    Index Scriptorium Estoniae

    Passila, Esko

    2007-01-01

    Autor leiab, et Ida-Virumaa peaks looma ühtse tugeva brändi, mille alusel tulevikuotsuseid teha. See peaks tooma välja soodsa asukoha eelised, võimalused, tööjõu kättesaadavuse, kasutusvalmid maa-alad, hinnad jne.

  5. Micropropagation of Araucaria excelsa R. Br. var. glauca Carrière from orthotropic stem explants.

    Science.gov (United States)

    Sarmast, Mostafa Khoshhal; Salehi, Hassan; Khosh-Khui, Morteza

    2012-07-01

    The objectives of the present work were in vitro propagation of Araucaria excelsa R. Br. var. glauca Carrière (Norfolk Island pine) with focus on the evaluation of the mean number of shoots per explant (MNS/E) and mean length of shoots per explants (MLS/E) produced by different parts of the orthotropic stem of A. excelsa R. Br. var. glauca in response to plant growth regulators. Norfolk Island pine axillary meristems responded very well to the 2-iso-pentenyl adenine (2iP) and thidiazuron (TDZ) levels. Explants taken from stem upper segments in the media containing 2iP had a higher MNS/E (3.47) and MLS/E (6.27 mm) in comparison to those taken from stem lower segments, which were 0.71 and 0.51 mm, respectively. Using 0.045 μM TDZ in the MS medium not only resulted in 4.60 MNS/E with 7.08 mm MLS/E but proliferated shoots showed a good performance as well. Investigating the best position of stem explant on mother plant as well as the best concentrations of growth regulators were performed which were useful for efficient micropropagation of this plant. Thirty three percent of explants were rooted in the MS medium containing 3 % sucrose, supplemented with 7.5 μM of both NAA and IBA for 2 weeks before transferring to a half strength MS medium without any growth regulator. Plantlets obtained were acclimatized and transferred to the greenhouse with less than 20 % mortality. This procedure considered the first successful report for regeneration and acclimatization of A. excelsa R. Br. var. glauca plantlet through main stem explants.

  6. Enhanced ionic conductivity with Li{sub 7}O{sub 2}Br{sub 3} phase in Li{sub 3}OBr anti-perovskite solid electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jinlong, E-mail: jlzhu04@physics.unlv.edu, E-mail: yusheng.zhao@unlv.edu, E-mail: zhaoys@sustc.edu.cn; Li, Shuai; Zhang, Yi; Howard, John W.; Wang, Yonggang; Kumar, Ravhi S.; Wang, Liping [High Pressure Science and Engineering Center, University of Nevada, Las Vegas, Nevada 89154 (United States); Lü, Xujie [Center for Integrated Nanotechnologies and Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Li, Yutao [Materials Research Program and The Texas Materials Institute, University of Texas at Austin, Texas 78712 (United States); Zhao, Yusheng, E-mail: jlzhu04@physics.unlv.edu, E-mail: yusheng.zhao@unlv.edu, E-mail: zhaoys@sustc.edu.cn [High Pressure Science and Engineering Center, University of Nevada, Las Vegas, Nevada 89154 (United States); Department of Physics, South University of Science and Technology of China, Guangdong 518055 (China)

    2016-09-05

    Cubic anti-perovskites with general formula Li{sub 3}OX (X = Cl, Br, I) were recently reported as superionic conductors with the potential for use as solid electrolytes in all-solid-state lithium ion batteries. These electrolytes are nonflammable, low-cost, and suitable for thermoplastic processing. However, the primary obstacle of its practical implementation is the relatively low ionic conductivity at room temperature. In this work, we synthesized a composite material consisting of two anti-perovskite phases, namely, cubic Li{sub 3}OBr and layered Li{sub 7}O{sub 2}Br{sub 3,} by solid state reaction routes. The results indicate that with the phase fraction of Li{sub 7}O{sub 2}Br{sub 3} increasing to 44 wt. %, the ionic conductivity increased by more than one order of magnitude compared with pure phase Li{sub 3}OBr. Formation energy calculations revealed the meta-stable nature of Li{sub 7}O{sub 2}Br{sub 3}, which supports the great difficulty in producing phase-pure Li{sub 7}O{sub 2}Br{sub 3} at ambient pressure. Methods of obtaining phase-pure Li{sub 7}O{sub 2}Br{sub 3} will continue to be explored, including both high pressure and metathesis techniques.

  7. Decommissioning of a small reactor (BR3 reactor, Belgium)

    International Nuclear Information System (INIS)

    Dadoumont, J.; Massaut, V.; Klein, M.; Demeulemeester, Y.

    2002-01-01

    Since 1989, SCK-CEN has been dismantling its PWR reactor BR3 (Belgian Reactor No. 3). After gaining a great deal of experience in remote dismantling of highly radioactive components during the actual dismantling of the two sets of internals, the BR3 team completed the cutting of its reactor pressure vessel (RPV). During the feasibility phase of the RPV dismantling, a decision was made to cut it under water in the refuelling pool of the plant, after having removed it from its cavity. The RPV was cut into segments using a milling cutter and a bandsaw machine. These mechanical techniques have shown their ability for this kind of operations. Prior to the segmentation, the thermal insulation situated around the RPV was remotely removed and disposed of. The paper will describe all these operations. The BR3 decommissioning activities also include the dismantling of contaminated loops and equipment. After a careful sorting of the pieces, optimized management routes are selected in order to minimize the final amount of radioactive waste to be disposed of. Some development of different methods of decontamination were carried out: abrasive blasting (or sand blasting), chemical decontamination (Oxidizing-Reducing process using Cerium). The main goal of the decontamination program is to recycle most of the metallic materials either in the nuclear world or in the industrial world by reaching the respective recycling or clearance level. Overall the decommissioning of the BR3 reactor has shown the feasibility of performing such a project in a safe and economical way. Moreover, BR3 has developed methodologies and decontamination processes to economically reduce the amount of radwaste produced. (author)

  8. Reactivity of BrCl, Br₂, BrOCl, Br₂O, and HOBr toward dimethenamid in solutions of bromide + aqueous free chlorine.

    Science.gov (United States)

    Sivey, John D; Arey, J Samuel; Tentscher, Peter R; Roberts, A Lynn

    2013-02-05

    HOBr, formed via oxidation of bromide by free available chlorine (FAC), is frequently assumed to be the sole species responsible for generating brominated disinfection byproducts (DBPs). Our studies reveal that BrCl, Br(2), BrOCl, and Br(2)O can also serve as brominating agents of the herbicide dimethenamid in solutions of bromide to which FAC was added. Conditions affecting bromine speciation (pH, total free bromine concentration ([HOBr](T)), [Cl(-)], and [FAC](o)) were systematically varied, and rates of dimethenamid bromination were measured. Reaction orders in [HOBr](T) ranged from 1.09 (±0.17) to 1.67 (±0.16), reaching a maximum near the pK(a) of HOBr. This complex dependence on [HOBr](T) implicates Br(2)O as an active brominating agent. That bromination rates increased with increasing [Cl(-)], [FAC](o) (at constant [HOBr](T)), and excess bromide (where [Br(-)](o)>[FAC](o)) implicate BrCl, BrOCl, and Br(2), respectively, as brominating agents. As equilibrium constants for the formation of Br(2)O and BrOCl (aq) have not been previously reported, we have calculated these values (and their gas-phase analogues) using benchmark-quality quantum chemical methods [CCSD(T) up to CCSDTQ calculations plus solvation effects]. The results allow us to compute bromine speciation and hence second-order rate constants. Intrinsic brominating reactivity increased in the order: HOBr ≪ Br(2)O Br(2) < BrCl. Our results indicate that species other than HOBr can influence bromination rates under conditions typical of drinking water and wastewater chlorination.

  9. Point Defect Properties of Cd(Zn)Te and TlBr for Room-Temperature Gamma Radiation Detectors

    Science.gov (United States)

    Lordi, Vincenzo

    2013-03-01

    The effects of various crystal defects in CdTe, Cd1-xZnxTe (CZT), and TlBr are critical for their performance as room-temperature gamma radiation detectors. We use predictive first principles theoretical methods to provide fundamental, atomic scale understanding of the defect properties of these materials to enable design of optimal growth and processing conditions, such as doping, annealing, and stoichiometry. Several recent cases will be reviewed, including (i) accurate calculations of the thermodynamic and electronic properties of native point defects and point defect complexes in CdTe and CZT; (ii) the effects of Zn alloying on the native point defect properties of CZT; (iii) point defect diffusion and binding related to Te clustering in Cd(Zn)Te; (iv) the profound effect of native point defects--principally vacancies--on the intrinsic material properties of TlBr, particularly electronic and ionic conductivity; (v) tailored doping of TlBr to independently control the electronic and ionic conductivity; and (vi) the effects of metal impurities on the electronic properties and device performance of TlBr detectors. Prepared by LLNL under Contract DE-AC52-07NA27344 with support from the National Nuclear Security Administration Office of Nonproliferation and Verification Research and Development NA-22.

  10. Skolēnu brīvā laika iespējas Jūrmalā

    OpenAIRE

    Proboks, Guntis

    2017-01-01

    Bakalaura darba projekta nosaukums ir: "Skolēnu brīvā laika iespējas Jūrmalā", autors: Guntis Proboks. Bakalaura darba ietvaros tiek izvirzīta problēma, ka bērnu un jauniešu brīvā laika pavadīšanas iespējas Jūrmalas pilsētā nav pietiekami attīstītas. Bakalaura darba mērķa sasniegšanai tiek izvirzīti sekojoši uzdevumi: iepazīties ar būtiskākajām definīcijām brīvā laika pavadīšanā un tūrismā, apkopot un analizēt aktuālās teorētiskās nostādnes brīvā laika pavadīšanā, raksturot tūrisma vēsturis...

  11. Ab initio NMR parameters of BrCH3 and ICH3 with relativistic and vibrational corrections

    Science.gov (United States)

    Uhlíková, Tereza; Urban, Štěpán

    2018-05-01

    This study is focused on two effects identified when NMR parameters are calculated based on first principles. These effects are 1. vibrational correction of properties when using ab initio optimized equilibrium geometry; 2. relativistic effects and limits of using the Flygare equation. These effects have been investigated and determined for nuclear spin-rotation constants and nuclear magnetic shieldings for the CH3Br and CH3I molecules. The most significant result is the difference between chemical shieldings determined based on the ab initio relativistic four-component Dirac-Coulomb Hamiltonian and chemical shieldings calculated using experimental values and the Flygare equation. This difference is approximately 320 ppm and 1290 ppm for 79Br and 127I in the CH3X molecule, respectively.

  12. Brûlure chez l’épileptique: brûlure pas comme les autres

    Science.gov (United States)

    Boukind, S.; Elatiqi, O.K.; Dlimi, M.; Elamrani, D.; Benchamkha, Y.; Ettalbi, S.

    2015-01-01

    Summary L’association brûlure et épilepsie est une constatation fréquente au Maroc. Ces brûlures, souvent itératives, touchent le plus souvent des femmes jeunes de milieu rural. L’accident survient habituellement au domicile, le plus souvent dans la cuisine à la suite d’une chute sur un moyen de cuisson posé au sol. Elles peuvent être inaugurales de la maladie mais surviennent plus souvent chez des patients connus mais au traitement mal suivi. Les conséquences de ces brûlures, toujours profondes, sont souvent dramatiques en termes de séquelles, chez des patients ayant déjà une insertion sociale rendue difficile par l’épilepsie. La prise en charge doit être multidisciplinaire et concerner à la fois la brûlures et l’épilepsie. Des mesures de prévention simples, visant à équilibrer l’épilepsie et éviter au patient de se trouver seul à proximité d’une source de chaleur, doivent être mises en place. PMID:27252613

  13. Thickness-dependent nonlinear optical properties of CsPbBr3 perovskite nanosheets.

    Science.gov (United States)

    Zhang, Jun; Jiang, Tian; Zheng, Xin; Shen, Chao; Cheng, Xiang'ai

    2017-09-01

    Halide perovskite has attracted significant attention because of excellent optical properties. Here, we study the optical properties of CsPbBr 3 perovskite nanosheets and observe that the nonlinear optical properties can be tuned by the thickness. The photoluminescence (PL) properties and nonlinear absorption effects induced by saturation absorption (SA) and two-photon absorption (TPA) in CsPbBr 3 nanosheets with different thicknesses (from 104.6 to 195.4 nm) have been studied. The PL intensity increases nearly three times with changing from the thinnest one to the thinnest under the same excitation condition. Moreover, the same phenomenon takes place no matter when SA or TPA effects happen. The PL lifetime (τ) varies inversely with the thickness. When SA happens, τ decreases from 11.54 to 9.43 ns while when TPA happens new decay channels emerge with the increase of the thickness. Besides, both saturation intensity (I sat ) and the modulation depth are proportional to the thickness (I sat rises from 3.12 to 4.79  GW/cm 2 , the modulation depth increases from 18.6% to 32.3%), while the TPA coefficient (β) is inversely proportional with the thickness (decreases from 10.94 to 4.73  cm/GW). In addition, quantum yields and thicknesses are in the direct ratio. This Letter advocates great promise for nonlinear optical property related photonics devices.

  14. HTO Approach Applications in ROSATOM CICET

    International Nuclear Information System (INIS)

    Volkov, E.; Aspidov, V.

    2016-01-01

    The paper presents Rosatom Central Institute for Continuing Education and Training (CICET) (hereinafter “CICET”) current activity in areas of nuclear facilities personnel training and relevant research. CICET has a strategic goal to get the “Safety Culture” competence centre for ROSATOM organizations. Safety culture ensures for nuclear organization to achieve both the business goals and high safety level. Safety is a state of ergatic [sic] system when influence of internal and external factors impact does not lead to its operation deterioration or stoppage. Dramatic history of world nuclear energetics shows that HOF the main assembly of factors influencing on safety. Individual work performance and organizational processes are visible, “artefact” part of the organization culture. Approaches and tools to enhance human and organization behavior are under CICET activity focus.

  15. HTO oral administration in mice: Pt. 1

    International Nuclear Information System (INIS)

    Yamamoto, O.; Yokoro, K.; Seyama, T.; Kinomura, A.; Nomura, T.

    1990-01-01

    Tritiated water in various concentrations was orally administered continuously to (C57BL/6N and C3H/He)F 1 female mice in a closed animal chamber. Tritium radioactivity in various organ tissues was measured periodically after initiating tritiated water intake using an automatic sample combustion system and a liquid scintillation counter. After 7 days the specific radioactivity reached a plateau. Within a range of 1.48 x 10 11 to 5.92 x 10 11 Bq/dm 3 as the concentration of tritiated water in drinking water, the time of death after initiating the administration was about 2 weeks, a typical time for haematopoietic death. A linear relationship of times of death with tritiated water concentrations in drinking water was observed, on a log-log scale, between 1.85 x 10 10 Bq/dm 3 and 1.48 x 10 11 Bq/dm 3 . At concentrations lower than 9.25 x 10 9 Bq/dm 3 , mice no longer died from haematopoietic failure. The authors conclude, therefore, that there should be a threshold dose rate for haematopoietic death. (author)

  16. Stratospheric HTO perturbations 1980-1983

    Science.gov (United States)

    Mason, A. S.

    1985-02-01

    Three perturbations of the stratospheric tritiated water burden have occurred. An atmospheric nuclear detonation in 1980 injected about 2.1 MCi. The massive eruptions of the volcano El Chichon may have contributed to a doubling of the removal rate in 1982. An unusually large wintertime exchange with the upper stratosphere may have occurred between 1982 and 1983.

  17. Non-enzymatic antioxidant accumulations in BR-deficient and BR-insensitive barley mutants under control and drought conditions.

    Science.gov (United States)

    Gruszka, Damian; Janeczko, Anna; Dziurka, Michal; Pociecha, Ewa; Fodor, Jozsef

    2017-12-07

    Drought is one of the most adverse stresses that affect plant growth and yield. Disturbances in metabolic activity resulting from drought cause overproduction of reactive oxygen species. It is postulated that brassinosteroids (BRs) regulate plant tolerance to the stress conditions, but the underlying mechanisms remain largely unknown. An involvement of endogenous BRs in regulation of the antioxidant homeostasis is not fully clarified either. Therefore, the aim of this study was to elucidate the role of endogenous BRs in regulation of non-enzymatic antioxidants in barley (Hordeum vulgare) under control and drought conditions. The plant material included the 'Bowman' cultivar and a group of semi-dwarf near-isogenic lines (NILs), representing mutants deficient in BR biosynthesis or signaling. In general, accumulations of 11 compounds representing various types of non-enzymatic antioxidants were analyzed under both conditions. The analyses of accumulations of reduced and oxidized forms of ascorbate indicated that the BR mutants contain significantly higher contents of dehydroascorbic acid under drought conditions when compared with the 'Bowman' cultivar. The analysis of glutathione accumulation indicated that under the control conditions the BR-insensitive NILs contained significantly lower concentrations of this antioxidant when compared with the rest of genotypes. Therefore, we postulate that BR sensitivity is required for normal accumulation of glutathione. A complete accumulation profile of various tocopherols indicated that functional BR biosynthesis and signaling are required for their normal accumulation under both conditions. Results of this study provided an insight into the role of endogenous BRs in regulation of the non-enzymatic antioxidant homeostasis. © 2017 Scandinavian Plant Physiology Society.

  18. Identification of Yellow Pigmentation Genes in Brassica rapa ssp. pekinensis Using Br300 Microarray

    Directory of Open Access Journals (Sweden)

    Hee-Jeong Jung

    2014-01-01

    Full Text Available The yellow color of inner leaves in Chinese cabbage depends on its lutein and carotene content. To identify responsible genes for yellow pigmentation in leaves, the transcriptome profiles of white (Kenshin and yellow leaves (Wheessen were examined using the Br300K oligomeric chip in Chinese cabbage. In yellow leaves, genes involved in carotene synthesis (BrPSY, BrPDS, BrCRTISO, and BrLCYE, lutein, and zeaxanthin synthesis (BrCYP97A3 and BrHYDB were upregulated, while those associated with carotene degradation (BrNCED3, BrNCED4, and BrNCED6 were downregulated. These expression patterns might support that the content of both lutein and total carotenoid was much higher in the yellow leaves than that in the white leaves. These results indicate that the yellow leaves accumulate high levels of both lutein and β-carotene due to stimulation of synthesis and that the degradation rate is inhibited. A large number of responsible genes as novel genes were specifically expressed in yellow inner leaves, suggesting the possible involvement in pigment synthesis. Finally, we identified three transcription factors (BrA20/AN1-like, BrBIM1, and BrZFP8 that are specifically expressed and confirmed their relatedness in carotenoid synthesis from Arabidopsis plants.

  19. Is the 'Bromine Explosion' generated from the reaction BrO HO2 alone?

    Science.gov (United States)

    Behnke, Wolfgang; Zetzsch, Cornelius

    2010-05-01

    We observed bromine explosions (a fast production of atomic Br and Cl under tropospheric conditions) in various smog chamber experiments in Teflon bags at room temperature at a relative humidity of about 80% in the presence of NaCl/NaBr-aerosol, simulated sunlight and ozone (200 - 400 ppb). Time profiles of ozone and hydrocarbons (HCs: n-butane, 2,2-dimethylbutane, tetramethylbutane and toluene, initially about 2 ppb each) were monitored to determine concentrations and source strengths of OH radicals, atomic Cl and Br and the corresponding time profiles of BrCl and Br2 as their photolytic precursors. The number and size of aerosols are measured as well as their chemical composition (Br-, Cl- and oxalic acid). Full records of raw data from the smog chamber runs are available at www.eurochamp.org for potential users. Chemical box model calculations deliver concentrations of various intermediates, such as aldehydes, HO2 and RO2 radicals and the inorganic halogen compounds ClO, BrO, HOCl and HOBr, where HOBr from O3 + Br- => BrO- + O2 in the aqueous/adsorbed phase induces the following gas-phase/ heterogeneous chain reaction Br + O3 => BrO + O2(1) BrO + HO2 => HOBr + O2(2a) HOBr + (Aerosol) => HOBrad(3) Surface-adsorbed HOBr reacts with Br- or Cl- to produce Br2 or BrCl, both of which are released and photolysed. Formation of Br2 should prevail up to Cl-/Br- -ratios of about 104 (Fickert, S., J.W. Adams, J.N. Crowley, J. Geophys. Res., D104, 23719-23727, 1999). A maximum of this ratio is reached about 30 minutes after the beginning and decreases during the next hours - probably by reaction of Br2 with oxalate and absorption of HBr, formed from the reaction of Br with aldehydes. Parallel to chain reaction (1)-(3) a chain reaction replacing Br by Cl seems possible but can not be realized, since the main sink of atomic Cl is its reaction with hydrocarbons - leading to chain termination - in contrast to atomic Br (ratio of rates: kCl[O3]/kCl[HC] ~ 0.1; kBr[O3]/kBr

  20. Material test reactor fuel research at the BR2 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Dyck, Steven Van; Koonen, Edgar; Berghe, Sven van den [Institute for Nuclear Materials Science, SCK-CEN, Boeretang, Mol (Belgium)

    2012-03-15

    The construction of new, high performance material test reactor or the conversion of such reactors' core from high enriched uranium (HEU) to low enriched uranium (LEU) based fuel requires several fuel qualification steps. For the conversion of high performance reactors, high density dispersion or monolithic fuel types are being developed. The Uranium-Molybdenum fuel system has been selected as reference system for the qualification of LEU fuels. For reactors with lower performance characteristics, or as medium enriched fuel for high performance reactors, uranium silicide dispersion fuel is applied. However, on the longer term, the U-Mo based fuel types may offer a more efficient fuel alternative and-or an easier back-end solution with respect to the silicide based fuels. At the BR2 reactor of the Belgian nuclear research center, SCK-CEN in Mol, several types of fuel testing opportunities are present to contribute to such qualification process. A generic validation test for a selected fuel system is the irradiation of flat plates with representative dimensions for a fuel element. By flexible positioning and core loading, bounding irradiation conditions for fuel elements can be performed in a standard device in the BR2. For fuel element designs with curved plates, the element fabrication method compatibility of the fuel type can be addressed by incorporating a set of prototype fuel plates in a mixed driver fuel element of the BR2 reactor. These generic types of tests are performed directly in the primary coolant flow conditions of the BR2 reactor. The experiment control and interpretation is supported by detailed neutronic and thermal-hydraulic modeling of the experiments. Finally, the BR2 reactor offers the flexibility for irradiation of full size prototype fuel elements, as 200mm diameter irradiation channels are available. These channels allow the accommodation of various types of prototype fuel elements, eventually using a dedicated cooling loop to provide the