WorldWideScience

Sample records for hto br i

  1. Revisiting the flavor changing neutral current Higgs decays $H\\to q_i q_j$ in the Standard Model

    CERN Document Server

    Benitez-Guzmán, L G; López-Osorio, M A; Martínez-Pascual, E; Toscano, J J

    2015-01-01

    An exact calculation of the Higgs boson decays $H\\to q_i q_j$ mediated by flavor changing neutral currents is presented in the context of the Standard Model. Using up-to-date experimental data, branching ratios of the order of $10^{-7}$, $10^{-8}$, $10^{-8}$, and $10^{-15}$ are found for the $\\bar{b}s+\\bar{s}b$, $\\bar{b}d+\\bar{d}b$, $\\bar{s}d+\\bar{d}s$, and $\\bar{c}u+\\bar{u}c$ decay modes, respectively.

  2. HTO - A complementary ergonomics approach.

    Science.gov (United States)

    Karltun, Anette; Karltun, Johan; Berglund, Martina; Eklund, Jörgen

    2017-03-01

    The field of human factors and ergonomics constitutes a strong potential in systems analysis, design and improvement. However, it is difficult to communicate its potential value. This paper addresses how the human-technology-organization (HTO) concept can be defined and supports the understanding, communication and development of the systems' character and potential of human factors and ergonomics. Empirical examples from the authors' experiences of working with the HTO concept in R&D and teaching are illustrated, including its usefulness as: 1) a conceptual model; 2) an analysis framework; 3) a meta methodology; 4) a pedagogical tool; and 5) a design tool. The use of HTO provides guidance on how the system can be designed to better support health, individual and systems performance. It is further suggested that there is a strong potential for developing the theory, applications and methodological aspects of HTO.

  3. Brændefyring i hjemmet - praksis holdninger og regulering

    DEFF Research Database (Denmark)

    Petersen, Lars Kjerulf; Martinsen, Louise

    Denne rapport handler om, hvorfor folk bruger brændeovne, hvordan de bruger dem, og hvilke funktioner brændeovnen har i hjemmet. Hygge er den vigtigste grund til at have og bruge en brændeovn, og de økonomiske fordele er den næstvigtigste grund. Udendørs røg fra brændefyring opleves i større eller...

  4. SOFC brændselsceller i et intelligent elnet

    DEFF Research Database (Denmark)

    Hjelm, Johan

    2015-01-01

    SOFC brændselsceller kan være med til at skabe balance i elnettet i takt med at elproduktionen i stigende grad baseres på sol og vind. Brændselscellerne kan kobles til naturgasnettet og på sigt bruge forskellige former for VE-gasser som brændstof.......SOFC brændselsceller kan være med til at skabe balance i elnettet i takt med at elproduktionen i stigende grad baseres på sol og vind. Brændselscellerne kan kobles til naturgasnettet og på sigt bruge forskellige former for VE-gasser som brændstof....

  5. 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

  6. 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

  7. Antireflective coating for AgBr-TlI and AgBr-TlBr0.46I0.54 solid solution crystals

    Science.gov (United States)

    Korsakov, Alexandr; Salimgareev, Dmitrii; Lvov, Alexandr; Zhukova, Liya

    2016-12-01

    We researched the process of ultraviolet (UV) irradiation for the crystals of AgBr-TlI and AgBr-TlBr0.46I0.54 systems. It was found that on the surface of irradiated crystals, the film is formed and film grain size depends on exposure time and crystal composition. This film proved to gain the transmission by reducing the reflection from its surface within the 8.0-27.0 μm range.

  8. Saltindhold i brød og morgenmadscerealier

    DEFF Research Database (Denmark)

    Trolle, Ellen; Saxholt, Erling; Knuthsen, Pia

    2016-01-01

    Saltindholdet i hvedebrød og rugbrød på de danske supermarkedshylder er faldet fra 2009 til 2014. En tilsvarende trend er ikke registreret i brød fra bagerbutikker. Udviklingen betyder, at en større andel af industrielt fremstillede brød end bagerbrød indsamlet i 2014 overholder Nøglehulsmærkets ...... overstiger Nøglehulsmærkets saltkrav. Saltindholdet er dog faldet i forhold til tidligere....

  9. Nordmenns brød- og kornvaner - i stabilitet og endring

    OpenAIRE

    Bugge, Annechen Bahr; Lavik, Randi; Lillebø, Kjersti

    2008-01-01

    Økt forbruk av grove brød- og kornprodukter er en sentral målsetting i Regjeringens handlingsplan for et bedre kosthold i befolkningen i perioden 2007 til 2011. Alle er imidlertid ikke enige i denne målsettingen. De senere årene har en rekke aktører satt spørsmålstegn ved brød- og kornprodukters ernæringsmessige verdi. Flere aktører har i den sammenheng oppfordret folk til å redusere inntaket av brød, pasta og andre sentrale karbohydrater i den norske matkulturen. Et sentralt tema i denne stu...

  10. Henrik Berggren Jessen & Claus Madsen: Ildfast i krydsild – standhaftig skoleledelse i brændpunktet

    Directory of Open Access Journals (Sweden)

    Jeffrey Hall

    2013-06-01

    Full Text Available «Å være ildfast – altså å tåle sterk varme gjennom lengre tid uten å krakelere og gå i stykker – må være en viktig egenskap for en skoleleder, eller for den saks skyld for enhver leder» (s. 13. Dette er bokens definisjon av hva som kreves av en leder i kryssilden mellom ulike interesser i læringsorganisasjoner, og der treffer den relativt godt. I boken «Ildfast i krydsild – standhaftig skoleledelse i brændpunktet» redegjør de danske forfatterne Henrik Berg Jessen og Claus Madsen for flere svært ulike perspektiver innen utdanningsledelse og management som har mer eller mindre sentrale i løpet av de siste to decenniene.

  11. The growth-form of <i>Euphorbia hedyotoidesi> N. E. Br. (syn. <i>E. decarianaI> Croiz.

    Directory of Open Access Journals (Sweden)

    Rauh, Werner

    1992-12-01

    Full Text Available A detailed description is given or <i>Euphorbia hedyotoidesi> N. E. Or. from southern Madagascar with a peculiar growth-form. Together with <i>E. eliotiii> Léandri it is placed in a separate group: the <i>E. hedyotoidesi>-group.
    >S'ofereix una detallada descripció d'una peculiar forma de creixement d'<i>E. hedyotoidesi> N. E. Or. procedent del sud de Madagascar. Es situa,juntament amb <i>E. eliotiii> Léandri, en un grup separat : el grup <i>E. hedyotoidesi>.

  12. Delayed neutron studies of separated isotopes of Br, Rb, I, and Cs

    CERN Document Server

    Reeder, R L; Wright, J F

    1976-01-01

    Discusses delayed neutron studies of separated isotopes of Br, Rb, I, and Cs are currently in progress at the Spectrometer for On-Line Analysis of Radionuclides (SOLAR) facility operated by Battelle, Pacific Northwest Laboratories. (2 refs).

  13. Analysis of an unusual hetero-halogen bonded trimer using charge density analysis: A case of concerted type I Br· · · Br and type II Br· · · Cl interactions

    Indian Academy of Sciences (India)

    MYSORE S PAVAN; TAYUR N GURU ROW

    2016-10-01

    The crystal structure of 4−bromo−2−chlorobenzoic acid generates an unusual triangular motif consisting of a hitherto uncharacterized Type I Br· · · Br contact along with two Type II Br· · · Cl interactions as edges of the triangle. The nature of such bonding is analyzed based on both experimental and theoretical chargedensity followed by topological analysis.

  14. Highly efficient visible light plasmonic photocatalyst Ag@Ag(Br,I).

    Science.gov (United States)

    Wang, Peng; Huang, Baibiao; Zhang, Qianqian; Zhang, Xiaoyang; Qin, Xiaoyan; Dai, Ying; Zhan, Jie; Yu, Jiaoxian; Liu, Haixia; Lou, Zaizhu

    2010-09-03

    The new plasmonic photocatalyst Ag@Ag(Br,I) was synthesized by the ion-exchange process between the silver bromide and potassium iodide, then by reducing some Ag(+) ions in the surface region of Ag(Br,I) particles to Ag(0) species. Ag nanoparticles are formed from Ag(Br,I) by the light-induced chemical reduction reaction. The Ag@Ag(Br,I) particles have irregular shapes with their sizes varying from 83 nm to 1 mum. The as-grown plasmonic photocatalyst shows strong absorption in the visible light region because of the plasmon resonance of Ag nanoparticles. The ability of this compound to reduce Cr(VI) under visible light was compared with those of other reference photocatalyst. The plasmonic photocatalyst is shown to be highly efficient under visible light. The stability of the photocatalyst was examined by X-ray diffraction and X-ray photoelectron spectroscopy. The XRD pattern and XPS spectra prove the stability of the plasmonic photocatalyst Ag@Ag(Br,I).

  15. New Scalar Contributions to $h\\to Z\\gamma$

    CERN Document Server

    Chen, Chian-Shu; Huang, Da; Tsai, Lu-Hsing

    2013-01-01

    We calculate the decay rate of $h\\to Z\\gamma$ by including the contributions from new scalars with arbitrary quantum numbers of the weak isospin ($T$) and hypercharge ($Y$) in the standard model. We find that our general formula for the decay rate of $h\\to Z\\gamma$ matches with that for $h\\to \\gamma\\gamma$ in the limit of $m_Z=0$, but it is different from those in the literature. To illustrate our result, by taking the current $2\\sigma$ excess of the $h\\to \\gamma\\gamma$rate measured by the LHC, we examine the corresponding shift for the $Z\\gamma$ decay channel due to the new scalar. We show that the enhancement or reduction of the $h\\to Z\\gamma$ rate only depends on the relative size of $T$ and the absolute value of $Y$. Explicitly, we predict $0.76

  16. Characteristic of Absorption Heat Transfer using LiBr+LiI Solution

    Science.gov (United States)

    Tsujimori, Atsushi; Ozaki, Eiichi; Nakao, Kazushige

    LiBr-H20 absorption chiller is widely used in Japan, and many research have been made for absorption characteristic in terms of enhancing heat transfer. Another study have been performed for widening working range with higher crystallization limits, and it was reported that adding LiI salt to LiBr-H20 working fluid provide about 5 [mass%] higher crystallization limit under the condition of absorption pressure range. It is necessary to reveal absorption heat transfer performance to utilize this working fluid pair for absorption chiller. In this study absorption heat transfer characteristic was investigated for horizontal and vertical tube. As a result, it was found that heat transfer coefficient increased as mass flow rate of solution increased and mass concentration of solution decrease and that these characteristic were almost the same as LiBr solution, though this solution gave slightly less heat transfer coefficient than LiBr solution.

  17. Resultater fra anden kortlægningsundersøgelse i Brønderslev Kommune 2016

    DEFF Research Database (Denmark)

    Nordahl, Thomas; Hansen, Line Skov; Øyen Nordahl, Sigrid

    Denne rapport baserer sig på to kortlægningsundersøgelser som er gennemført i dagtilbud og skoler i Brønderslev Kommune. Den første kortlægningsundersøgelse blev gennemført i december 2013 til januar 2014, og den anden kortlægningsundersøgelse blev gennemført i januar – februar 2016. De to kortlæ......Denne rapport baserer sig på to kortlægningsundersøgelser som er gennemført i dagtilbud og skoler i Brønderslev Kommune. Den første kortlægningsundersøgelse blev gennemført i december 2013 til januar 2014, og den anden kortlægningsundersøgelse blev gennemført i januar – februar 2016. De...

  18. Konkretiseringsmateriell i arbeid med brøk

    OpenAIRE

    Lundstadsveen, Hedda Johanne

    2016-01-01

    Fractions are a complex concept, and many students struggle in their first approach with it. In this study I have considered how 8th grade students used concrete materials in relation to their work with fractions, in light of the socio-cultural perspective of learning. This study was based on this research question: How do students in 8th grade perceive the concept of fraction through the use of concrete materials when solving tasks? To answer this research question, the use of concrete...

  19. Effects of SbBr3 addition to CH3NH3PbI3 solar cells

    Science.gov (United States)

    Oku, Takeo; Ohishi, Yuya; Suzuki, Atsushi

    2017-01-01

    TiO2/CH3NH3Pb1-xSbxI3-2xBr3x-based photovoltaic devices were fabricated, and effects of SbBr3 addition to CH3NH3PbI3 precursor solutions on the photovoltaic properties were investigated. The short-circuit current densities and photoconversion efficiencies were improved by adding a small amount of SbBr3 to the perovskite phase, which would be due to a doping effect of Sb or Br atoms at the Pb or I sites.

  20. Complexes of InBr/sub 3/ and InI/sub 3/ with azomethines

    Energy Technology Data Exchange (ETDEWEB)

    Danilicheva, I.I.; Lyapina, S.S.; Leshchenko, A.V. (Voroshilovgradskij Mashinostroitel' nyj Inst. (Ukrainian SSR))

    1983-06-01

    Complexes of InBr/sub 3/ and InI/sub 3/ with some azomethine ligands are synthesized. It is shown that these compounds are related to molecular compounds with a donor-acceptor bond localized on a nitrogen atom of a azomethine group. Complexes of the InBr/sub 3/x3L composition are the most characteristic for indium tribromide, as indium triiodide forms compounds of the InI/sub 3/x2L and InI/sub 3/xL composition. These complexes are isostructural ones independently on ligand system volume and chemical nature and place of substituents. Complexes are practically unsoluble in usual nonpolar organic solvents, but their solubility perceptibly grows in polar solvents. Obtained complexes are binar electrolytes of the medium force. Hydrolytic decomposition of complexes is studied.

  1. X-ray excited optical luminescence studies on the system Ba (, =F, Cl, Br, I)

    Indian Academy of Sciences (India)

    K Govinda Rajan; A Jestin Lenus

    2005-08-01

    The present paper reports the experimental observations on the x-ray excited optical luminescence (XEOL) along with the afterglow and colour center features found for the barium salts, represented by the formula, Ba, where and are the halides. The system thus consists of four dihalides (BaF2, . . . ,BaI2) and six mixed halides (BaFCl,. . . ,BaBrI). To start with, it was found that on two of the binary halides of barium, BaClI and BaBrI, no literature exists, and so these were prepared for the first time and their crystal structures were determined. An x-ray generator of 3-kW rating was next coupled to a spectrometer via a high throughput fiberoptic sensor for recording the luminescence spectra under x-irradiation. Also presented in this paper are the observations on the Ba compounds in which about 0.1 mole% of Eu2+ was doped, in order to study the efficiency between the prompt luminescence and the photostimulated luminescence in these compounds. The crystal structure varies from fluorite (BaF2), to matlockite (BaF) and finally to orthorhombic (BaCl2, . . .,BaBrI) for these compounds. Hence searching for systematics and empirical relations in the observed XEOL behaviour of these compounds is still a challenging problem.

  2. Resultater fra to kvalitative casestudier i Brønderslev Kommune 2016

    DEFF Research Database (Denmark)

    Drugli, May Britt; Frederiksen, Pia; Hansen, Ole Henrik

    I denne rapport præsenteres resultaterne af to kvalitative casestudier, som på forskellig vis omhandler arbejdet med læringsmiljøudvikling i Brønderslev Kommunes dagtilbud og skoler via forsknings- og udviklingsprojektet ’Udvikling i fællesskaber’ (2013-2016). Projektet involverer et treårigt...... og anden kortlægningsundersøgelse (Nordahl et al., 2017; Qvortrup et al., 2015) fremadrettet skal danne grundlag for pædagogiske initiativer i form af ledelsestiltag, pædagogiske udviklingsaktiviteter og ledelses- og kompetenceudviklingsaktiviteter på kommune-, institutions- og teamniveau....

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

    Science.gov (United States)

    Sherwen, Tomás; Schmidt, Johan A.; Evans, Mat J.; Carpenter, Lucy J.; Großmann, Katja; Eastham, Sebastian D.; Jacob, Daniel J.; Dix, Barbara; Koenig, Theodore K.; Sinreich, Roman; Ortega, Ivan; Volkamer, Rainer; Saiz-Lopez, Alfonso; Prados-Roman, Cristina; Mahajan, Anoop S.; Ordóñez, Carlos

    2016-09-01

    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.

  4. Photocatalytic properties of BiOX (X=Cl, Br, and I)

    Institute of Scientific and Technical Information of China (English)

    AN Huizhong; DU Yi; WANG Tianmin; WANG Cong; HAO Weichang; ZHANG Junying

    2008-01-01

    A novel series of photocatalysts, bismuth oxyhalide (BiOX, X=Cl, Br, and I), were synthesized by a hydrolysis method. The powder samples were characterized by the use of X-ray diffraction (XRD), scanning electron microscope, and UV-Vis spectrophotometer. The XRD pattern showed that all the BiOX were well crystallized in the tetragonal structure. The band gaps of the sheet-shaped compounds BiOX (X=Cl, Br, and I) were 3.44, 2.76, and 1.85 eV, respectively. BiOBr showed the highest photocatalytic activity in degrading rhodamine B (RhB) and evolving O2 for its proper valence band (VB). BiOI has no photocatalytic activity. BiOCl showed the highest activity in decomposing isopropanol because of electron-hole pair separation through trapping electrons by oxygen vacancies.

  5. Engineering BiOX (X = Cl, Br, I) nanostructures for highly efficient photocatalytic applications

    Science.gov (United States)

    Cheng, Hefeng; Huang, Baibiao; Dai, Ying

    2014-01-01

    Heterogeneous photocatalysis that employs photo-excited semiconductor materials to reduce water and oxidize toxic pollutants upon solar light irradiation holds great prospects for renewable energy substitutes and environmental protection. To utilize solar light effectively, the quest for highly active photocatalysts working under visible light has always been the research focus. Layered BiOX (X = Cl, Br, I) are a kind of newly exploited efficient photocatalysts, and their light response can be tuned from UV to visible light range. The properties of semiconductors are dependent on their morphologies and compositions as well as structures, and this also offers the guidelines for design of highly-efficient photocatalysts. In this review, recent advances and emerging strategies in tailoring BiOX (X = Cl, Br, I) nanostructures to boost their photocatalytic properties are surveyed.

  6. Fabrication and characterization of CH3NH3(Cs)Pb(Sn)I3(Br) perovskite solar cells

    Science.gov (United States)

    Ueoka, Naoki; Ohishi, Yuya; Shirahata, Yasuhiro; Suzuki, Atsushi; Oku, Takeo

    2017-01-01

    Perovskite-type CH3NH3(MA)PbI3-based photovoltaic devices were fabricated and characterized. Doping effects of cesium iodide (CsI), cesium bromide (CsBr) and tin bromide (SnBr2) on the photovoltaic properties and surface microstructures of the perovskite phase were investigated. Short-circuit current densities, open-circuit voltages and fill factors increased by CsI and SnBr2 addition. The surface coverage of the perovskite crystals was also improved by SnBr2 doping, which resulted in improvement of the fill factor. The cell prepared by a starting composition of MA0.95Cs0.05Pb0.95Sn0.05I2.90Br0.10 showed the best photovoltaic performance in the present work.

  7. [(Ph)3PBr][Br7], [(Bz)(Ph)3P]2[Br8], [(n-Bu)3MeN]2[Br20], [C4MPyr]2[Br20], and [(Ph)3PCl]2[Cl2I14]: extending the horizon of polyhalides via synthesis in ionic liquids.

    Science.gov (United States)

    Wolff, Michael; Okrut, Alexander; Feldmann, Claus

    2011-11-21

    The five polyhalides [(Ph)(3)PBr][Br(7)], [(Bz)(Ph)(3)P](2)[Br(8)], [(n-Bu)(3)MeN](2)[Br(20)], [C(4)MPyr](2)[Br(20)] ([C(4)MPyr] = N-butyl-N-methylpyrrolidinium), and [(Ph)(3)PCl](2)[Cl(2)I(14)] were prepared by the reaction of dibromine and iodine monochloride in ionic liquids. The compounds [(Ph)(3)PBr][Br(7)] and [(Bz)(Ph)(3)P](2)[Br(8)] contain discrete pyramidal [Br(7)](-) and Z-shaped [Br(8)](2-) polybromide anions. [(n-Bu)(3)MeN](2)[Br(20)] and [C(4)MPyr](2)[Br(20)] exhibit new infinite two- and three-dimensional polybromide networks and contain the highest percentage of dibromine ever observed in a compound. [(Ph)(3)PCl](2)[Cl(2)I(14)] also consists of a three-dimensional network and is the first example of an infinite polyiodine chloride. All compounds were obtained from ionic liquids as the solvent that, on the one hand, guarantees for a high stability against strongly oxidizing Br(2) and ICl and that, on the other hand, reduces the high volatility of the molecular halogens.

  8. $\\beta$-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...

  9. $\\beta$-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...

  10. CP violation in $h\\to \\tau\\tau$ and LFV $h\\to \\mu\\tau$

    CERN Document Server

    Hayreter, Alper; Valencia, German

    2016-01-01

    The CMS collaboration has reported a possible lepton flavour violating (LFV) signal $h\\to\\mu\\tau$. Whereas this does not happen in the standard model (SM), we point out that new physics responsible for this type of decay would, in general, also produce charge-parity (CP) violation in $h\\to \\tau\\tau$. We estimate the size of this effect in a model independent manner and find that a large asymmetry, of order 40\\%, is allowed by current constraints.

  11. A Comparison of Apparent Diffusion Coefficients Measured in Compacted Kunigel V1 Bentonite with those Calculated from Batch Sorption Measurements and D{sub e} (HTO) Data: A Case Study for Cs(I), Ni(II), Sm(III), Am(III), Zr(IV) and Np(V)

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, M.; Baeyens, B

    2003-02-01

    Recently, a bentonite sorption data base, comprising values taken from batch sorption data, was developed for a performance assessment study for high-level waste and spent fuel (Entsorgungsnachweis). Thus distribution coefficients (K{sub d}) determined on dispersed systems were used to calculate apparent diffusion coefficients (D{sub a}) subsequently applied in diffusive transport calculations for the highly compacted system. Whenever such a procedure is adopted, questions invariably arise as to whether this is conservative or not. On the occasions when K{sub d} values have been extracted from (mainly) indiffusion experiments and compared with those obtained from batch tests, apparent discrepancies have been found. In the majority of cases the batch values are larger, sometimes significantly. Hypotheses from 'surface diffusion' to 'double layer pore constrictivity effects' have been proposed to explain the inconsistencies. However, although such discrepancies have been reported periodically over the past twenty years or so, and have become generally accepted facts of life, there are surprisingly few quantitative studies directly dealing with this issue. Further, two other points are worthy of mention. The first is that a diffusion model (including the associated assumptions) is needed in order to deduce K{sub d} values from diffusion measurements. Thus the sorption values calculated are model dependent. The second is that too little attention has been paid to the potential effects of water chemistry, i.e. a comparison between sorption values is only valid when the water chemistry in the batch tests is the same as, or very close to, the porewater chemistry in the intact material. In practice, this condition is difficult to achieve because of the uncertainties concerning the latter. This report describes a study in which K{sub d} values for Cs(I), Ni(II), Sm(III), Am(III), Zr(IV) and Np(V) were calculated from in-diffusion data published in the

  12. Electronic structures and geometries of the XF{sub 3} (X = Cl, Br, I, At) fluorides

    Energy Technology Data Exchange (ETDEWEB)

    Sergentu, Dumitru-Claudiu [SUBATECH, UMR CNRS 6457, IN2P3/EMN Nantes/Université de Nantes, 4 Rue A. Kastler, BP 20722, 44307 Nantes Cedex 3 (France); CEISAM, UMR CNRS 6230, Université de Nantes, 2 Rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3 (France); Amaouch, Mohamed; Pilmé, Julien [Sorbonne Universités, UPMC Univ Paris 06, UMR 7616, Laboratoire de Chimie Théorique, Case Courier 137, 4 Place Jussieu, 75252 Paris Cedex 05 (France); CNRS, UMR 7616, Laboratoire de Chimie Théorique, Case Courier 137, 4 Place Jussieu, 75252 Paris Cedex 05 (France); Galland, Nicolas, E-mail: nicolas.galland@univ-nantes.fr [CEISAM, UMR CNRS 6230, Université de Nantes, 2 Rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3 (France); Maurice, Rémi, E-mail: remi.maurice@subatech.in2p3.fr [SUBATECH, UMR CNRS 6457, IN2P3/EMN Nantes/Université de Nantes, 4 Rue A. Kastler, BP 20722, 44307 Nantes Cedex 3 (France)

    2015-09-21

    The potential energy surfaces of the group 17 XF{sub 3} (X = Cl, Br, I, At) fluorides have been investigated for the first time with multiconfigurational wave function theory approaches. In agreement with experiment, bent T-shaped C{sub 2v} structures are computed for ClF{sub 3}, BrF{sub 3}, and IF{sub 3}, while we predict that an average D{sub 3h} structure would be experimentally observed for AtF{sub 3}. Electron correlation and scalar relativistic effects strongly reduce the energy difference between the D{sub 3h} geometry and the C{sub 2v} one, along the XF{sub 3} series, and in the X = At case, spin-orbit coupling also slightly reduces this energy difference. AtF{sub 3} is a borderline system where the D{sub 3h} structure becomes a minimum, i.e., the pseudo-Jahn-Teller effect is inhibited since electron correlation and scalar-relativistic effects create small energy barriers leading to the global C{sub 2v} minima, although both types of effects interfere.

  13. Electronic structures and geometries of the XF3 (X = Cl, Br, I, At) fluorides.

    Science.gov (United States)

    Sergentu, Dumitru-Claudiu; Amaouch, Mohamed; Pilmé, Julien; Galland, Nicolas; Maurice, Rémi

    2015-09-21

    The potential energy surfaces of the group 17 XF3 (X = Cl, Br, I, At) fluorides have been investigated for the first time with multiconfigurational wave function theory approaches. In agreement with experiment, bent T-shaped C(2v) structures are computed for ClF3, BrF3, and IF3, while we predict that an average D(3h) structure would be experimentally observed for AtF3. Electron correlation and scalar relativistic effects strongly reduce the energy difference between the D(3h) geometry and the C(2v) one, along the XF3 series, and in the X = At case, spin-orbit coupling also slightly reduces this energy difference. AtF3 is a borderline system where the D(3h) structure becomes a minimum, i.e., the pseudo-Jahn-Teller effect is inhibited since electron correlation and scalar-relativistic effects create small energy barriers leading to the global C(2v) minima, although both types of effects interfere.

  14. Comparison of LaBr3:Ce and NaI(Tl) Scintillators for Radio-Isotope Identification Devices

    Energy Technology Data Exchange (ETDEWEB)

    Milbrath, Brian D.; Choate, Bethany J.; Fast, Jim E.; Hensley, Walter K.; Kouzes, Richard T.; Schweppe, John E.

    2006-07-31

    Lanthanum halide (LaBr3:Ce) scintillators offer significantly better resolution (<3 percent at 662 kilo-electron volt [keV]) relative to sodium iodide (NaI(Tl)) and have recently become commercially available in sizes large enough for the hand-held radio-isotope identification device (RIID) market. There are drawbacks to lanthanum halide detectors, however. These include internal radioactivity that contributes to spectral counts and a low-energy response that can cause detector resolution to be lower than that of NaI(Tl) below 100 keV. To study the potential of this new material for RIIDs, we performed a series of measurements comparing a 1.5?1.5 inch LaBr?3:Ce detector with an Exploranium GR 135 RIID, which contains a 1.5-2.2 inch NaI(Tl) detector. Measurements were taken for short time frames, as typifies RIID usage. Measurements included examples of naturally occurring radioactive material (NORM), typically found in cargo, and special nuclear materials. Some measurements were noncontact, involving short distances or cargo shielding scenarios. To facilitate direct comparison, spectra from the different detectors were analyzed with the same isotope identification software (ORTEC ScintiVision TM). In general, the LaBr3:Ce detector was able to find more peaks and find them faster than the NaI(Tl) detector. To the same level of significance, the LaBr3:Ce detector was usually two to three times faster. The notable exception was for 40K containing NORM where interfering internal contamination in the LaBr3:Ce detector exist. NaI(Tl) consistently outperformed LaBr3:Ce for this important isotope. LaBr3:Ce currently costs much more than NaI(Tl), though this cost-difference is expected to diminish (but not completely) with time. As is true of all detectors, LaBr3:Ce will need to be gain-stabilized for RIID applications. This could possibly be done using the internal contaminants themselves. It is the experience of the authors that peak finding software in RIIDs needs to be

  15. [The deposition of tritium in form of HTO from atmosphere moisture to Hypogymnia physodes lichens during chamber experiments].

    Science.gov (United States)

    Golubeva, V N; Golubev, A V; Kosheleva, T A; Kuznetsova, V F; Mavrin, S V

    2008-01-01

    The results of the deposition of tritium oxide (HTO) from atmosphere to Hypogymnia physodes lichens during chamber experiments are presented. For lichens the content of tissue water tritium (TWT) and organically bound tritium (OBT) were measuremed. Were shown that lichens mainly absorb HTO from atmosphere during first 24 hours. The ratio TWT/HTO of chamber and the velocity of TWT to OBT conversion in lichens were determined. Was noted that the TWT to OBT conversion velocity for lichens is ten times greater than that for deposition of HTO by vascular plant leafs. There was supposed that TWT to OCT conversion in lichens is occurred through alga as well as fungus component of lichens. The intensive deposition HTO from chamber atmosphere by lichens and high velocity of HTO to OBT conversion show the availability to use lichens for determination of atmosphere pollution by HTO.

  16. 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 ...

  17. Straightforward synthesis of [Au(NHC)X] (NHC = N-heterocyclic carbene, X = Cl, Br, I) complexes.

    Science.gov (United States)

    Collado, Alba; Gómez-Suárez, Adrián; Martin, Anthony R; Slawin, Alexandra M Z; Nolan, Steven P

    2013-06-21

    An improved protocol for the synthesis of [Au(NHC)X] (X = Cl, Br, I) complexes is reported. This versatile one-step synthetic methodology proceeds under mild conditions, in air, using technical grade solvents, is scalable and is applicable to a wide range of imidazolium and imidazolidinium salts.

  18. 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.

  19. Absence of RNase H allows replication of pBR322 in Escherichia coli mutants lacking DNA polymerase I.

    Science.gov (United States)

    Kogoma, T

    1984-12-01

    rnh (formerly termed sdrA) mutants of Escherichia coli K-12, capable of continuous DNA replication in the absence of protein synthesis (stable DNA replication), are devoid of ribonuclease H (RNase H, EC 3.1.26.4) activity. Plasmid pBR322 was found to replicate in rnh mutants in the absence of DNA polymerase I, the polA gene product, which is normally required for replication of this plasmid. The plasmid copy number in polA rnh double mutants was as high as in the wild-type strains. When a chimeric construct between pBR322 and pSC101 was introduced into a polA rnh double mutant, the replication of the plasmid via the pBR322 replicon was inhibited if the plasmid also carried an rnh+ gene or if the host harbored an F' plasmid carrying an rnh+ gene. Thus, DNA polymerase I-independent replication of pBR322 requires the absence of RNase H activity. This alternative mechanism requiring neither DNA polymerase I nor RNase H appears to involve a transcriptional event in the region of the normal origin of replication.

  20. Periodicity, Electronic Structures, and Bonding of Gold Tetrahalides [AuX4](-) (X = F, CI, Br, I, At, Uus)

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wan-Lu; Li, Yong; Xu, Congqiao; Wang, Xue B.; Vorpagel, Erich R.; Li, Jun

    2015-12-07

    Systematic theoretical and experimental investigations have been performed to understand the periodicity and electronic structures of trivalent-gold halides using gold tetrahalides [AuX4]⁻ anions (X = F, Cl, Br, I, At, Uus). The [AuX4]⁻ (X = Cl, Br, I) anions were produced in gas phase and their negative-ion photoelectron spectra were obtained, which exhibited rich and well-resolved spectral peaks. We calculated the adiabatic as well as vertical electron detachment energies using density functional methods with scalar and spin-orbit coupling relativistic effects. The simulated photoelectron spectra based on these calculations are in good agreement with the experimental spectra. Our results show that the trivalent Au(III) oxidation state becomes progressively less stable while Au(I) is preferred when the halides become heavier along the Period Table. This trend reveals that the oxidation state of metals in complexes can be manipulated through ligand design

  1. Exploration of new second-order nonlinear optical materials of the Cs-Hg-Br-I system.

    Science.gov (United States)

    Wu, Qi; Huang, Yin; Meng, Xianggao; Zhong, Cheng; Chen, Xingguo; Qin, Jingui

    2014-06-21

    A first example of a Cs-Hg-Br-I system, namely Cs2Hg2Br2I4·H2O (1), has been synthesized by reaction in solution. It belongs to the polar monoclinic space group pc with a = 7.460(5) Å, b = 13.458(9) Å, c = 8.891(6) Å, and β = 92.448(9)°. The basic anionic group in the crystal is non-centrosymmetric [Hg2Br2I4](2-), and the groups are aligned in the same direction in the crystal. As a result, 1 exhibits a phase-matchable second harmonic generation (SHG) response as strong as 6 times that of KH2PO4 (KDP). For the purpose of comparison, the known compound Cs2Hg3I8·H2O (2) was also synthesized and its SHG properties were studied for the first time. Band structure and optical property calculations for the two compounds based on DFT methods were also performed. The comprehensive properties of 1 and 2 as well as their analog, Cs2HgCl2I2, have been compared and discussed.

  2. NMR Kinetics of the S[subscript N]2 Reaction between BuBr and I[superscript -]: An Introductory Organic Chemistry Laboratory Exercise

    Science.gov (United States)

    Mobley, T. Andrew

    2015-01-01

    A simple organic chemistry experiment is described that investigates the kinetics of the reaction between 1-bromobutane (BuBr) and iodide (I[superscript -]) as followed by observing the disappearance of BuBr and the appearance of 1-iodobutane (BuI) using [superscript 1]H NMR spectroscopy. In small groups of three to four, students acquire data to…

  3. NMR Kinetics of the S[subscript N]2 Reaction between BuBr and I[superscript -]: An Introductory Organic Chemistry Laboratory Exercise

    Science.gov (United States)

    Mobley, T. Andrew

    2015-01-01

    A simple organic chemistry experiment is described that investigates the kinetics of the reaction between 1-bromobutane (BuBr) and iodide (I[superscript -]) as followed by observing the disappearance of BuBr and the appearance of 1-iodobutane (BuI) using [superscript 1]H NMR spectroscopy. In small groups of three to four, students acquire data to…

  4. A theoretical study of the carbenoids LiCH2X (X = Cl, Br, I) cyclopropanation reaction with ketene

    Indian Academy of Sciences (India)

    Xing Hui Zhang; Fu Long Zhang; Zhi Yuan Geng

    2010-05-01

    A computational study for the [2 + 1] addition of the lithium carbenoids LiCH2X (X = Cl, Br, I) with ketene have been investigated by means of the B3LYP hybrid density functional method. All the reactions examined displayed similar concerted mechanisms for the cyclopropanation of these reagents. The lithium carbenoids react with ketene via an asynchronous attack on one CH2 or C group of ketene with relatively low barrier to reaction in the range of 25.34-33.74 kJ/mol in THF solvent. The trend of the lithium carbenoids reaction barrier with ketene is LiCH2Cl < LiCH2Br < LiCH2I. The results show that the reactions could be highly chemical reactivity with low barriers and could be favoured in experiment. The reactions could proceed easily at lower temperature. The computational results are briefly compared to other carbenoid reactions and related species.

  5. Zintl Salts Ba2P7X (X = Cl, Br, and I: Synthesis, Crystal, and Electronic Structures

    Directory of Open Access Journals (Sweden)

    Juli-Anna Dolyniuk

    2013-08-01

    Full Text Available Two barium phosphide halides, Ba2P7Br and Ba2P7I, were synthesized and structurally characterized by single crystal X-ray diffraction. Both compounds crystallize in the monoclinic space group P21/m (No. 11 and are isostructural to Ba2P7Cl. The crystal structures of Ba2P7X (X = Cl, Br, I feature the presence of heptaphosphanortricyclane P73− clusters along with halogen anions and barium cations. According to the Zintl concept, Ba2P7X compounds are electron-balanced semiconductors. Quantum-chemical calculations together with UV-Visible spectroscopy confirm the title compounds are wide bandgap semiconductors. The bonding in the P73− clusters was analyzed by means of electron localization function. The elemental compositions were confirmed using energy dispersive X-ray spectroscopy.

  6. Double-inversion mechanisms of the X⁻ + CH₃Y [X,Y = F, Cl, Br, I] SN2 reactions.

    Science.gov (United States)

    Szabó, István; Czakó, Gábor

    2015-03-26

    The double-inversion and front-side attack transition states as well as the proton-abstraction channels of the X(-) + CH3Y [X,Y = F, Cl, Br, I] reactions are characterized by the explicitly correlated CCSD(T)-F12b/aug-cc-pVTZ(-PP) level of theory using small-core relativistic effective core potentials and the corresponding aug-cc-pVTZ-PP bases for Br and I. In the X = F case the double-inversion classical(adiabatic) barrier heights are 28.7(25.6), 15.8(13.4), 13.2(11.0), and 8.6(6.6) kcal mol(-1) for Y = F, Cl, Br, and I, respectively, whereas the barrier heights are in the 40-90 kcal mol(-1) range for the other 12 reactions. The abstraction channels are always above the double-inversion saddle points. For X = F, the front-side attack classical(adiabatic) barrier heights, 45.8(44.8), 31.0(30.3), 24.7(24.2), and 19.5(19.3) kcal mol(-1) for Y = F, Cl, Br, and I, respectively, are higher than the corresponding double-inversion ones, whereas for the other systems the front-side attack saddle points are in the 35-70 kcal mol(-1) range. The double-inversion transition states have XH···CH2Y(-) structures with Cs point-group symmetry, and the front-side attack saddle points have either Cs (X = F or X = Y) or C1 symmetry with XCY angles in the 78-88° range. On the basis of the previous reaction dynamics simulations and the minimum energy path computations along the inversion coordinate of selected XH···CH2Y(-) systems, we suggest that the double inversion may be a general mechanism for SN2 reactions.

  7. On the electronic structure and thermoelectric properties of BiTeBr and BiTeI single crystals and of BiTeI with the addition of BiI{sub 3} and CuI

    Energy Technology Data Exchange (ETDEWEB)

    Kulbachinskii, Vladimir A., E-mail: kulb@mig.phys.msu.ru [Faculty of Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Kytin, Vladimir G.; Kudryashov, Alexey A. [Faculty of Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Kuznetsov, Alexei N.; Shevelkov, Andrei V. [Chemistry Department, Lomonosov Moscow State University, Moscow 119991 (Russian Federation)

    2012-09-15

    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{sub 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 model. The

  8. Organic-inorganic halide perovskite solar cell with CH3NH3PbI2Br as hole conductor

    Science.gov (United States)

    Zhang, Shufang; Zhang, Chenming; Bi, Enbing; Miao, Xiaoliang; Zeng, Haibo; Han, Liyuan

    2017-01-01

    Perovskite solar cells (PSCs) have attracted enormous interest as the most remarkably growing photovoltaic devices. With the power conversion efficiencies of PSCs excessing 20%, great challenges have been focused on the issues of cost and long-term stability which are majorly related to the hole transport materials. In contrast, the PSCs without special hole conductors show great potential for commercial applications due to their cost-effective and fairly stable features. However, the inferior charge separation at the CH3NH3PbI3 (MAPbI3) and back electrode interface limits the cells for high efficiency. Our strategy is to arrange suitable energy band alignment at the interface to enhance the charge separation. We herein report a MAPbI3/MAPbI2Br cascade structured PSC with MAPbI2Br majorly acting as a hole conductor. The conversion efficiency of the PSCs is greatly improved and a high efficiency of 15.83% is achieved. This new design of using organic-inorganic halide perovskites as hole conductors provides an efficient approach for improving the performance of low-cost PSCs.

  9. Energy resolution of LaBr3:Ce in a phoswich configuration with CsI:Na and NaI:Tl scintillator crystals

    Science.gov (United States)

    Hull, G.; Genolini, B.; Josselin, M.; Matea, I.; Peyré, J.; Pouthas, J.; Zerguerras, T.

    2012-12-01

    We studied the performances of the LaBr3:Ce scintillator when optically coupled to NaI:Tl and CsI:Na in a Phoswich detector for the R&D phase of the gamma ray calorimeter PARIS (Photon Array for the studies with Radioactive Ion and Stable beams). This detector has the purpose to measure γ-energies in a wide range (100 keV-40 MeV), and it will be used principally as a part of the SPIRAL2 instrumentation at GANIL. In this communication we report on the study of the light yield and energy resolution for gamma detection realized by coupling the phoswiches with various photomultiplier tubes, providing different characteristics. We were interested in investigating the possible degradation of the scintillation light produced by the LaBr3:Ce due to the presence of NaI:Tl/CsI:Na crystals, before being detected on the photocathode. For this purpose we realized all the measurements employing a standard ADC and QDC read-out system leading the possibility to perform a gate-based event selection. In this study we measured an energy resolution of 4.6% with an uncollimated 137Cs source for a 50.8×50.8×50.8 mm3 LaBr3:Ce coupled to a 50.8×50.8×152.4 mm3 NaI:Tl. This value is 30% bigger than the energy resolution measured for a 50.8×50.8×101.6 mm3 stand-alone LaBr3:Ce but still in the specifications for the PARIS collaboration physics list.

  10. Potential impacts of CF3I on ozone as a replacement for CF3Br in aircraft applications

    Directory of Open Access Journals (Sweden)

    D. Youn

    2006-06-01

    Full Text Available Iodotrifluoromethane (CF3I has been considered to be a candidate replacement for bromotrifluoromethane (CF3Br, which is used in aircraft for fuel inerting and for fire fighting. In this study, the chemical effects of aircraft-released CF3I on atmospheric ozone were examined with the University of Illinois at Urbana-Champaign two-dimensional chemical-radiative-transport (UIUC 2-D CRT model. Using an earlier estimate of the aircraft emission profile for tank inerting in military aircraft, the resulting equivalent Ozone Depletion Potentials (ODPs for CF3I were in the range of 0.07 to 0.25. As a sensitivity study, we also analyzed CF3I emissions associated with fuel inerting if it were to occur at lower altitudes using an alternative estimate. The model calculations of resulting effects on ozone for this case gave ODPs≤0.05. Furthermore, through interactions with the National Institute of Standards and Technology (NIST, we analyzed the potential effects on ozone resulting from using CF3I in fire fighting connected with engine nacelle and auxiliary power unit applications. The scenarios evaluated using the NIST estimate suggested that the ODPs obtained by assuming aircraft flights occurring in several different latitude regions of the Northern Hemisphere are extremely low. According to the model calculation, the altitude where CF3I is released from aircraft is a dominant factor in its ozone depletion effects. On the assumption that the CF3I emission profile is representative of actual release characteristics, aircraft-released CF3I has much lower impacts on the ozone layer and can be a qualified substitute of CF3Br in engine nacelles.

  11. Potential impacts of CF3I on ozone as a replacement for CF3Br in aircraft applications

    Directory of Open Access Journals (Sweden)

    Y. Li

    2006-01-01

    Full Text Available Iodotrifluoromethane (CF3I has been considered to be a candidate replacement for bromotrifluoromethane (CF3Br, which is used in aircraft for fuel inerting and for fire fighting. In this study, the chemical effects of aircraft-released CF3I on atmospheric ozone were examined with the University of Illinois at Urbana-Champaign two-dimensional chemical-radiative-transport (UIUC 2-D CRT model. Using an earlier estimate of the aircraft emission profile for tank inerting in military aircraft, the resulting equivalent Ozone Depletion Potentials (ODPs for CF3I were in the range of 0.07 to 0.25. As a sensitivity study, we also analyzed CF3I emissions associated with fuel inerting if it were to occur at lower altitudes using an alternative estimate. The model calculations of resulting effects on ozone for this case gave ODPs≤0.05. Furthermore, through interactions with the National Institute of Standards and Technology (NIST, we analyzed the potential effects on ozone resulting from using CF3I in fire fighting connected with engine nacelle and auxiliary power unit applications. The scenarios evaluated using the NIST estimate suggested that the ODPs obtained by assuming aircraft flights occurring in several different latitude regions of the Northern Hemisphere are extremely low. According to the model calculation, the altitude where CF3I is released from aircraft is a dominant factor in its ozone depletion effects. On the assumption that the CF3I emission profile is representative of actual release characteristics, aircraft-released CF3I has much lower impacts than CF3Br.

  12. The trapping effect of sulfur sensitization center Ag2S cluster on T-grain AgBrI microcrystals

    Institute of Scientific and Technical Information of China (English)

    YANG; Shaopeng; FU; Guangsheng; LI; Xiaowei; TIAN; Xiaodo

    2004-01-01

    The microwave absorption dielectric-spectrum technique was used to study the decay kinetics of photoelectrons in sulfur-sensitized silver halide crystals. The time-resolution spectrum of free electrons and shallow-trapped electrons generated in sulfur-sensitized AgBrI crystals has been obtained. The relationship of the trapping effect of sensitization centers Ag2S and sensitization time or temperature in emulsions has been discussed. With the increase in the sensitization time and temperature, the trap effect of sulfur sensitization centers varies from hole trap to shallow electron trap, and deep electron trap.

  13. Unconventional superconductivity in electron-doped layered metal nitride halides MNX (M = Ti, Zr, Hf; X = Cl, Br, I)

    Energy Technology Data Exchange (ETDEWEB)

    Kasahara, Yuichi, E-mail: ykasahara@scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan); Kuroki, Kazuhiko, E-mail: kuroki@phys.sci.osaka-u.ac.jp [Department of Physics, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Yamanaka, Shoji, E-mail: syamana@hiroshima-u.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8527 (Japan); Taguchi, Yasujiro, E-mail: y-taguchi@riken.jp [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan)

    2015-07-15

    In this review, we present a comprehensive overview of superconductivity in electron-doped metal nitride halides MNX (M = Ti, Zr, Hf; X = Cl, Br, I) with layered crystal structure and two-dimensional electronic states. The parent compounds are band insulators with no discernible long-range ordered state. Upon doping tiny amount of electrons, superconductivity emerges with several anomalous features beyond the conventional electron–phonon mechanism, which stimulate theoretical investigations. We will discuss experimental and theoretical results reported thus far and compare the electron-doped layered nitride superconductors with other superconductors.

  14. The structure of the homogeneous oxidation catalyst, Mn(II)-Br(-I)x, in supercritical water: An x-ray absorption fine structure study

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yongsheng; Fulton, John L.; Partenheimer, Walt

    2005-10-12

    Extended x-ray absorption fine structure (EXAFS) and x-ray absorption near edge structure (XANES) spectroscopies were used to probe the first-shell coordination structure of Mn(II) and Br(-I) ion pairs in supercritical water. This work was performed to clarify why solutions of MnBr2 in supercritical water are known to effectively catalyze the aerobic oxidative synthesis of terephthalic acid from p-xylene. The Mn and Br K-edge spectra were collected at the bending magnet beamline (sector 20) at the Advanced Photon Source, Argonne. The first-shell coordination structure about the Mn(II) ion changes from octahedral at ambient conditions to tetrahedral at supercritical conditions. Under supercritical conditions, the measured bond distances of Mn-OH2 and Mn-Br are 2.11 and 2.46 ?, respectively. Direct contact ion pairs form with about 2 Br(-I) ions present in the first coordination shell of the Mn(II) ion. The structure of dissolved MnBr2, below 1.0 m, changes from essentially [Mn(II)(H2O)6]+2 to [Mn(II)(H2O)2(Br)2] in supercritical water (scH2O). When an excess of a Br(-I) ion is added, the bromide coordination increases and the number of water molecules decreases. The results show that the initial MnBr2 catalyst in scH2O is tetrahedral with two Mn-Br contact ion pairs. The presence of the acetate anion deactivates the catalyst by formation of insoluble MnO.

  15. Barroso: EL-i liikmesriigid õõnestavad Brüsseli mainet / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2010-01-01

    Eurobaromeetri küsitluse kohaselt arvab vaid 49% EL-i kodanikest, et EL-i liige on hea olla. Euroopa Komisjoni president Jose Manuel Barroso näeb EL-i populaarsuse kahanemises süüd eelkõige liikmesriikide valitsustel. Andmeid uuringust

  16. Barroso: EL-i liikmesriigid õõnestavad Brüsseli mainet / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2010-01-01

    Eurobaromeetri küsitluse kohaselt arvab vaid 49% EL-i kodanikest, et EL-i liige on hea olla. Euroopa Komisjoni president Jose Manuel Barroso näeb EL-i populaarsuse kahanemises süüd eelkõige liikmesriikide valitsustel. Andmeid uuringust

  17. Search for Flavor Changing Neutral Current in $t\\to H c, H\\to \\tau\\tau$ Decay at the LHC

    CERN Document Server

    Chen, Xin

    2015-01-01

    The prospects of searching for a Flavor Changing Neutral Current (FCNC) effect in the decay of $t\\to H c, H\\to \\tau\\tau$ with simulated $p-p$ collision data from the ATLAS detector at LHC are investigated, where the neutral Higgs mass assumed to be 125 GeV. To improve the Higgs mass reconstruction, a di-$\\tau$ mass fit with constraints from Higgs mass and tau kinematics is performed per event level, which significantly improves the Higgs and top mass reconstruction, and helps signal-background separation. Boosted Decision Trees (BDT) discriminants are further developed to achieve an optimal sensitivity for the FCNC signal search. An expected 95\\% confidence-level upper limit of 0.32\\% can be set on the branching ratio BR($t\\to H c$) with $100 ~fb^{-1}$ of data collected at $\\sqrt{s}=13$ TeV during LHC Run 2 period.

  18. Tunable Br-doping CH3NH3PbI3-xBrx thin films for efficient planar perovskite solar cells

    Science.gov (United States)

    Li, Nannan; Shi, Chengwu; Li, Long; Zhang, Zhengguo; Ma, Chengfeng

    2017-04-01

    In this paper, the relationship of the Br contents in precursor solutions of the CH3NH3Br/CH3NH3I mixture and in the resulting CH3NH3PbI3-xBrx thin films was systemically explored and the tunable Br-doping CH3NH3PbI3-xBrx thin films were successfully obtained by the sequential deposition methods. The influence of CH3NH3Br content in the methylammonium halide mixture solutions on the chemical composition, optical absorption, crystal phase and morphology of CH3NH3PbI3-xBrx thin films and the photovoltaic performance of the corresponding planar perovskite solar cells were investigated. The result revealed that the Br contents in CH3NH3PbI3-xBrx thin films linearly increased with the increase of Br contents in the methylammonium halide mixture solutions. The planar perovskite solar cell based on the high crystallinity and less grain boundary CH3NH3PbI3-xBrx thin films using the methylammonium halide mixture solutions with the molar ratio of CH3NH3Br/CH3NH3I = 10/90 achieved a best photoelectric conversion efficiency (PCE) of 14.88% with an open-circuit voltage (Voc) of 1.03 V, a short-circuit photocurrent density (Jsc) of 20.62 mA cm-2 and a fill factor (FF) of 0.70 and an average PCE of 14.21 ± 0.67% with Voc of 1.02 ± 0.02 V, Jsc of 20.67 ± 0.15 mA cm-2 and FF of 0.67 ± 0.05.

  19. Development of surgical gamma probes with TlBr semiconductors and CsI(Tl) scintillators crystals; Desenvolvimento de sondas cirurgicas radioguiadas com semicondutores de TlBr e com cristais cintiladores de CsI (Tl)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Fabio Eduardo da

    2006-07-01

    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)

  20. High-pressure synthesis and crystal structures of beta- M NX (M = Zr, Hf; X = Cl, Br, I)

    CERN Document Server

    Chen, X; Yamanaka, S

    2002-01-01

    The single crystals of six kinds of metal nitride halide, beta- M NX (M = Zr, Hf; X = Cl, Br, I), were grown in sealed Au (or Pt) tubes by the reaction of M N or M NX powders with NH sub 4 X as fluxes under high-temperature and high-pressure conditions such as 3-5 GPa at 900-1200 sup o C. The x-ray structure analysis revealed that all six kinds of compound crystallize in a rhombohedral space group R3-bar m, Z = 6. beta-ZrNCl, beta-ZrNBr, and beta-HfNCl are isotypic with SmSI, and the others isostructural with YOF.

  1. 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.

  2. Theoretical prediction of noble gas inserted halocarbenes: FNgCX (Ng = Kr, and Xe; X = F, Cl, Br, and I)

    Science.gov (United States)

    Chopra, Pragya; Ghosh, Ayan; Roy, Banasri; Ghanty, Tapan K.

    2017-09-01

    A new series of neutral noble gas inserted compounds involving halocarbenes, mainly, FNgCX (Ng = Kr, and Xe; X = F, Cl, Br, and I) has been predicted through various ab initio quantum chemical techniques such as MP2, DFT, CCSD(T) and MRCI. The structure, stabilities, charge distribution, harmonic vibrational frequencies and topological properties of these compounds have been investigated. It is found that the predicted species are energetically stable with respect to all the plausible 2-body and 3-body dissociation pathways, with the exception of the 2-body channel that leads to the global minimum products (FCX + Ng). Despite this, existence of finite barrier heights indicates that these compounds are kinetically stable with respect to global minimum products. The computational results indicate that it might be possible to prepare and characterize the most stable singlet state of FNgCX molecules under cryogenic conditions through suitable experimental technique(s).

  3. Vibrational energy relaxation of liquid aryl-halides X-C6H5 (X = F, Cl, Br, I).

    Science.gov (United States)

    Pein, Brandt C; Seong, Nak-Hyun; Dlott, Dana D

    2010-10-07

    Anti-Stokes Raman spectroscopy was used to probe vibrational energy dynamics in liquid ambient-temperature aryl-halides, X-Ph (X = F, Cl, Br, I; -Ph = C(6)H(5)), following IR excitation of a 3068 cm(-1) CH-stretching transition. Five ring vibrations and two substituent-dependent vibrations were monitored in each aryl-halide. Overall, the vibrational relaxation (VR) lifetimes in aryl-halides were shorter than those in normal benzene (H-Ph). The aryl-halide CH-stretch lifetimes increased in the order F, Cl, Br, I, ranging from 2.5 to 3.4 ps, compared with 6.2 ps in H-Ph. The aryl-halide energy transfer processes were similar overall with four exceptions. Three of the four exceptions could be explained as a result of faster VR of midrange vibrations (1000-1600 cm(-1)) in the heavier aryl-halides. The fourth appeared to result from a coincidental resonance in chlorobenzene that does not occur in the other aryl-halides. Among the aryl-halides, the decay of CH-stretching excitations (∼3070 cm(-1)) was slower in the heavier species, but the decay of midrange vibrations was faster in the heavier species. This seeming contradiction could be explained if VR depended primarily on the density of states (DOS) of the lower tiers of vibrational excitations. The DOS for the first few (1-4) tiers is similar for all aryl-halides in the CH-stretch region, but DOS increases with increasing halide mass in the midrange region.

  4. The bonding picture in hypervalent XF3 (X = Cl, Br, I, At) fluorides revisited with quantum chemical topology.

    Science.gov (United States)

    Amaouch, Mohamed; Sergentu, Dumitru-Claudiu; Steinmetz, David; Maurice, Rémi; Galland, Nicolas; Pilmé, Julien

    2017-08-03

    Hypervalent XF3 (X = Cl, Br, I, At) fluorides exhibit T-shaped C2V equilibrium structures with the heavier of them, AtF3 , also revealing an almost isoenergetic planar D3h structure. Factors explaining this behavior based on simple "chemical intuition" are currently missing. In this work, we combine non-relativistic (ClF3 ), scalar-relativistic and two-component (X = Br - At) density functional theory calculations, and bonding analyses based on the electron localization function and the quantum theory of atoms in molecules. Typical signatures of charge-shift bonding have been identified at the bent T-shaped structures of ClF3 and BrF3 , while the bonds of the other structures exhibit a dominant ionic character. With the aim of explaining the D3h structure of AtF3 , we extend the multipole expansion analysis to the framework of two-component single-reference calculations. This methodological advance enables us to rationalize the relative stability of the T-shaped C2v and the planar D3h structures: the Coulomb repulsions between the two lone-pairs of the central atom and between each lone-pair and each fluorine ligand are found significantly larger at the D3h structures than at the C2v ones for X = Cl - I, but not with X = At. This comes with the increasing stabilization, along the XF3 series, of the planar D3h structure with respect to the global T-shaped C2v minima. Hence, we show that the careful use of principles that are at the heart of the valence shell electron pair repulsion model provides reasonable justifications for stable planar D3h structures in AX3 E2 systems. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  5. Reactions of Cu(I)Br with aziridine derivatives. Synthesis, characterization and crystal structures of monomeric, dimeric and hexameric aziridine (= az) complexes of the formal type [CuBr(az)2]n (n = 1, 2) and [CuBr(az)]6.

    Science.gov (United States)

    Bobka, Roman; Roedel, J Nicolas; Wirth, Stefan; Lorenz, Ingo-Peter

    2010-11-14

    The first syntheses of monomeric and oligomeric aziridine complexes of copper(I) are described. Cu(I)Br (1) reacts with a series of different aziridine derivatives (C(2)H(3)PhNH (2), C(2)H(2)Me(2)NH (3), C(2)H(2)Me(2)NC(2)H(2)Me(2)NH(2) (4)) to give the neutral dimeric complex [CuBr(C(2)H(3)PhNH)(2)](2) (5) and the ionic hexameric complex [Cu(6)Br(5)(C(2)H(2)Me(2)NH)(6)]Br (6) with terminal bound aziridine ligands as well as the neutral monomeric complex [CuBr(C(2)H(2)Me(2)NC(2)H(2)Me(2)NH(2))] (7) where the dimerized aziridine acts as a N,N'-chelating ligand. After purification, all of the complexes were fully characterized and their IR, (1)H and (13)C NMR spectra are reported and discussed. The single crystal structure analysis revealed distorted tetrahedral geometry for the copper(I) centres in the complexes 5 and 6 and a trigonal planar structure for complex 7. In the oligomers the copper centres are bridged by two μ(2)- (5) or two μ(3)- and three μ(4)-bromido ligands (6), respectively.

  6. 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.

  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. 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)

  9. Vapor-Phase Epitaxial Growth of Aligned Nanowire Networks of Cesium Lead Halide Perovskites (CsPbX3, X = Cl, Br, I).

    Science.gov (United States)

    Chen, Jie; Fu, Yongping; Samad, Leith; Dang, Lianna; Zhao, Yuzhou; Shen, Shaohua; Guo, Liejin; Jin, Song

    2017-01-11

    With the intense interest in inorganic cesium lead halide perovskites and their nanostructures for optoelectronic applications, high-quality crystalline nanomaterials with controllable morphologies and growth directions are desirable. Here, we report a vapor-phase epitaxial growth of horizontal single-crystal CsPbX3 (X = Cl, Br, I) nanowires (NWs) and microwires (MWs) with controlled crystallographic orientations on the (001) plane of phlogopite and muscovite mica. Moreover, single NWs, Y-shaped branches, interconnected NW or MW networks with 6-fold symmetry, and, eventually, highly dense epitaxial network of CsPbBr3 with nearly continuous coverage were controllably obtained by varying the growth time. Detailed structural study revealed that the CsPbBr3 wires grow along the [001] directions and have the (100) facets exposed. The incommensurate heteroepitaxial lattice match between the CsPbBr3 and mica crystal structures and the growth mechanism of these horizontal wires due to asymmetric lattice mismatch were proposed. Furthermore, the photoluminescence waveguiding and good performance from the photodetector device fabricated with these CsPbBr3 networks demonstrated that these well-connected CsPbBr3 NWs could serve as straightforward platforms for fundamental studies and optoelectronic applications.

  10. Pressure dependence of band-gap and phase transitions in bulk CuX (X = Cl, Br, I)

    Energy Technology Data Exchange (ETDEWEB)

    Azhikodan, Dilna; Nautiyal, Tashi [Department of Physics, Indian Institute of Technology Roorkee, Uttarakhand - 247 667 (India); Sharma, S. [Max-Planck-Institut of Microstructure Physics, Weinberg 2, D-06120 Halle (Germany)

    2016-05-06

    Usually a phase transition, in theoretical studies, is explored or verified by studying the total energy as a function of the volume considering various plausible phases. The intersection point, if any, of the free energy vs. volume curves for the different phases is then the indicator of the phase transition(s). The question is, can the theoretical study of a single phase alone indicate a phase transition? i.e. can we look beyond the phase under consideration through such a study? Using density-functional theory, we report a novel approach to suggest phase transition(s) through theoretical study of a single phase. Copper halides have been engaged for this study. These are direct band-gap semiconductors, with zinc blende structure at ambient conditions, and are reported to exhibit many phase transitions. We show that the study of volume dependence of energy band-gap in a single phase facilitates looking beyond the phase under consideration. This, when translated to pressures, reflects the phase transition pressures for CuX (X = Cl, Br, I) with an encouraging accuracy. This work thus offers a simple, yet reliable, approach based on electronic structure calculations to investigate new semiconducting materials for phase changes under pressure.

  11. Blending of NR/BR/EPDM by reactive processing for tire sidewall applications. I. Preparation, cure characteristics and mechanical properties

    NARCIS (Netherlands)

    Sahakaro, Kannika; Naskar, Nityananda; Datta, Rabin N.; Noordermeer, Jacques W.M.

    2007-01-01

    EPDM incorporated into blends of natural rubber/butadiene rubber (NR/BR) improves ozone resistance. In this work, the inferior mechanical properties of NR/BR/EPDM blends generally obtained by conventional straight mixing are overcome by utilizing a reactive processing technique. The entire amount of

  12. CROSSED MOLECULAR BEAM STUDIES OF CHEMILUMINESCENT REACTIONS: F{sub 2} + I{sub 2}, Br{sub 2} and ICl

    Energy Technology Data Exchange (ETDEWEB)

    Kahler, C.C.; Lee, Y.T.

    1980-05-01

    The chemiluminescent bimolecular halogen-halogen reactions, F{sub 2} + I{sub 2}, Br{sub 2} and ICl, have been studied by the crossed molecular beam technique. Undispersed chemiluminescence was measured as a function of collision energy and, for I{sub 2} + F{sub 2}, as a function of the two beam pressures. Although no spectra were obtained to positively identify the emitters as IF*, ClF* and BrF*, arguments are given to support this identification. The observed reaction thresholds of 4.2 and 5.9 kcal/mole for I{sub 2} + F{sub 2} and ICl + F{sub 2} , respectively, are the same as the threshold energies for production of the stable trihalogens I{sub 2}F and ClF. This coincidence of threshold energies, as well as similar high collision energy behavior, implies that the chemiluminescent reaction proceeds via a stable trihalogen intermediate. This mechanism can explain our results and the results of other workers without resorting to a symmetry forbidden four center reaction mechanism. A threshold of 11.3 kcal/mole was found for Br{sub 2} + F{sub 2} , no threshold for Br{sub 2}F has been previously reported. Laser enhancement of the I{sub 2} + F{sub 2} reaction was attempted, but no enhancement was seen.

  13. Simulation calculations of efficiencies and silicon consumption for CH3NH3PbI3-x-y Br x Cl y /crystalline silicon tandem solar cells

    Science.gov (United States)

    Zhang, Lili; Xie, Ziang; Tian, Fuyang; Qin, Guogang

    2017-04-01

    Much attention has been paid to two-subcell tandem solar cells (TSCs) with crystalline silicon (c-Si) as the bottom cell (TSC-Si). Previous works have pointed out that the optimal band gap, E g, of the top cell material for a TSC-Si is around 1.75 eV. With a tunable E g and better stability than MAPbI3 (MA  =  CH3NH3), MAPbI3-x-y Br x Cl y is a promising candidate for the top cell material of a TSC-Si. In this work, calculations concerning the E g, refractive index and extinction coefficient of MAPbI3-x-y Br x Cl y are performed using first-principles calculations including the spin-orbit coupling (SOC) effect. MAPbI3-x-y Br x Cl y with five sets of x and y, which have a E g around 1.75 eV, are obtained. On this basis, absorption of the perovskite top cell is calculated applying the Lambert-Beer model (LBM) and the transfer matrix model (TMM), respectively. Considering the Auger recombination in the c-Si bottom cell and radiation coupling between the two subcells, the efficiencies for MAPbI3-x-y Br x Cl y /c-Si TSCs with the five sets of x and y are calculated. Among them, the MAPbI2.375Br0.5Cl0.125/c-Si TSC achieves the highest efficiency of 35.1% with a 440 nm thick top cell and 50 µm thick c-Si when applying the LBM. When applying the TMM, the highest efficiency of 32.5% is predicted with a 580 nm thick MAPbI2.375Br0.5Cl0.125 top cell and 50 µm thick c-Si. Compared with the limiting efficiency of 27.1% for a 190 µm thick c-Si single junction solar cell (SC), the MAPbI2.375Br0.5Cl0.125/c-Si TSC shows a superior performance of high efficiency and low c-Si consumption.

  14. Relativistic and correlation effects on molecular properties .1. The dihalogens F-2, Cl-2, Br-2, I-2, and At-2

    NARCIS (Netherlands)

    Visscher, L; Dyall, K.G.

    1996-01-01

    A benchmark study of a number of relativistic correlation methods is presented. Bond lengths, harmonic frequencies, and dissociation energies of the molecules F-2, Cl-2, Br-2, I-2, and At-2 are calculated at various levels of theory, using both the Schrodinger and the Dirac-Coulomb-(Gaunt) Hamiltoni

  15. 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)

  16. Heterogeneous photocatalysts BiOX/NaBiO3 (X = Cl, Br, I): Photo-generated charge carriers transfer property and enhanced photocatalytic activity

    Science.gov (United States)

    Ji, Lei; Wang, Haoren; Yu, Ruimin

    2016-10-01

    BiOX/NaBiO3 (X = Cl, Br, I) heterostructures were synthesized by a simple chemical etching method using haloid acid as etching agents to react with NaBiO3. Several characterization tools including X-ray powder diffraction (XRD), scanning electron microscope (SEM) and UV-vis diffuse reflectance spectra (UV-vis DRS) were employed for structural and composition analyses of the samples. The as-prepared heterogeneous samples exhibited more efficient photocatalytic activities than pure NaBiO3 and BiOX (X = Cl, Br, I) for the degradation of Rhodamine B (RhB) under visible light (or UV light) irradiation, which could be attributed to the formation of the p-n junction between p-BiOX (X = Cl, Br, I) and n-NaBiO3, which effectively suppresses the recombination of photo-generated electron-hole pairs. Terephthalic acid photoluminescence (TA-PL) probing test and trapping agents experiments demonstrated that radOH (or h+) was the dominant reactive species depend on the different band gap structure of the p-n heterojunctions. Possible transfer processes of photo-generated charge carriers were proposed based on the band structures of BiOX/NaBiO3 (X = Cl, Br, I) and the experimental results.

  17. 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.

  18. 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)NH4OH 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.

  19. Theoretical X-ray production cross sections at incident photon energies across L{sub i} (i=1-3) absorption edges of Br

    Energy Technology Data Exchange (ETDEWEB)

    Puri, Sanjiv [Department of Basic & Applied Sciences, Punjabi University, Patiala-147002, Punjab, India. E-mail address: sanjivpurichd@yahoo.com (India)

    2015-08-28

    The X-ray production (XRP) cross sections, σ{sub Lk} (k = l, η, α, β{sub 6}, β{sub 1}, β{sub 3}, β{sub 4}, β{sub 9,10}, γ{sub 1,5}, γ{sub 2,3}) have been evaluated at incident photon energies across the L{sub i}(i=1-3) absorption edge energies of {sub 35}Br using theoretical data sets of different physical parameters, namely, the L{sub i}(i=1-3) sub-shell the X-ray emission rates based on the Dirac-Fock (DF) model, the fluorescence and Coster Kronig yields based on the Dirac-Hartree-Slater (DHS) model, and two sets of the photoionisation cross sections based on the relativistic Hartree-Fock-Slater (RHFS) model and the Dirac-Fock (DF) model, in order to highlight the importance of electron exchange effects at photon energies in vicinity of absorption edge energies.

  20. 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.

  1. Comprehensive theoretical studies on the low-lying electronic states of NiF, NiCl, NiBr, and NiI.

    Science.gov (United States)

    Zou, Wenli; Liu, Wenjian

    2006-04-21

    The low-lying electronic states of the nickel monohalides, i.e., NiF, NiCl, NiBr, and NiI, are investigated by using multireference second-order perturbation theory with relativistic effects taken into account. For the energetically lowest 11 lambda-S states and 26 omega states there into, the potential energy curves and corresponding spectroscopic constants (vertical and adiabatic excitation energies, equilibrium bond lengths, vibrational frequencies, and rotational constants) are reported. The calculated results are grossly in very good agreement with those solid experimental data. In particular, the ground state of NiI is shown to be different from those of NiF, NiCl, and NiBr, being in line with the recent experimental observation. Detailed analyses are provided on those states that either have not been assigned or have been incorrectly assigned by previous experiments.

  2. Photoelectron spectroscopy of aqueous solutions: streaming potentials of NaX (X = Cl, Br, and I) solutions and electron binding energies of liquid water and X-.

    Science.gov (United States)

    Kurahashi, Naoya; Karashima, Shutaro; Tang, Ying; Horio, Takuya; Abulimiti, Bumaliya; Suzuki, Yoshi-Ichi; Ogi, Yoshihiro; Oura, Masaki; Suzuki, Toshinori

    2014-05-07

    The streaming potentials of liquid beams of aqueous NaCl, NaBr, and NaI solutions are measured using soft X-ray, He(I), and laser multiphoton ionization photoelectron spectroscopy. Gaseous molecules are ionized in the vicinity of liquid beams and the photoelectron energy shifts are measured as a function of the distance between the ionization point and the liquid beam. The streaming potentials change their polarity with concentration of electrolytes, from which the singular points of concentration eliminating the streaming potentials are determined. The streaming currents measured in air also vanish at these concentrations. The electron binding energies of liquid water and I(-), Br(-), and Cl(-) anions are revisited and determined more accurately than in previous studies.

  3. 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

  4. Fe+与CH3X(X=Cl,Br,I)反应的理论研究%A Theoretical Study of the Reaction of Fe+ with CH3X (X=Cl, Br,I)

    Institute of Scientific and Technical Information of China (English)

    孙小丽; 李吉来; 黄旭日; 孙家锺

    2013-01-01

    铁及其复合物催化的C—X键功能化日益引起人们的重视.采用密度泛函理论(DFT),在B3LYP/def2-SVP水平下详细研究了Fe+与CH3X (X=Cl,Br,I)的反应活性和机理.计算结果表明标题反应存在两种反应机制,即插入机制和SN2机制.从机理上来看,在插入机理中,反应都始于Fe+离子从侧面进攻CH3X,生成产物FeX+和CH3*;而在SN2机制中,反应则始于Fe+离子从背后进攻CH3X,生成产物FeCH+和X*.从我们的计算可以看出,四重态或六重态下的Fe+离子在C—X键活化中展现了截然不同的催化活性;在所有通道中,都以四重态为主导;SN2机制中相对较高的决速能垒使其丧失了竞争性.再者,计算表明在所有的插入机制中,所有通道都是放热的,而在SN2机制中,仅有X=I时,反应是放热的.此外,计算表明这些反应属于两态反应活性,两种机制中,在反应的入口和出口存在最小能量交叉点.此外,反应途径电子结构追踪分析表明自旋极化对能量影响较大,调控着反应采取的反应通道和主副产物比例.通过本文的理论研究,尤其是详细的电子结构分析,为铁催化剂活化C—X键和C—C耦联反应提供了线索和以铁为基的催化剂设计提供理论依据.

  5. Synthesis, structural and optical characterization of APbX{sub 3} (A=methylammonium, dimethylammonium, trimethylammonium; X=I, Br, Cl) hybrid organic-inorganic materials

    Energy Technology Data Exchange (ETDEWEB)

    Mancini, Alessandro; Quadrelli, Paolo; Amoroso, Giuseppe; Milanese, Chiara [Department of Chemistry and INSTM, University of Pavia, Pavia 27100 (Italy); Boiocchi, Massimo [University of Pavia, Centro Grandi Strumenti, 27100 Pavia (Italy); Sironi, Angelo [University of Milano and INSTM, Via Golgi 19, 20133 Milano (Italy); Patrini, Maddalena; Guizzetti, Giorgio [University of Pavia and CNISM, Via Bassi 6, 27100 Pavia (Italy); Malavasi, Lorenzo, E-mail: lorenzo.malavasi@unipv.it [Department of Chemistry and INSTM, University of Pavia, Pavia 27100 (Italy)

    2016-08-15

    In this paper we report the synthesis, the crystal structure and the optical response of APbX{sub 3} (A=MA, DMA, and TMA; X=I, Br) hybrid organic-inorganic materials including some new phases. We observe that as the cation group increases in size, the optical absorption edge shifts to higher energies with energy steps which are systematic and independent on the anion. A linear correlation between the optical bad gap and the tolerance factor has been shown for the series of samples investigated. - Graphical abstract: The crystal structure and the optical response of the two series of hybrid organic-inorganic materials APbX{sub 3} (A=MA, DMA, and TMA; X=I, Br), which include some new phases, are reported. A dependence of crystal structure and band-gap with tolerance factor is shown. Display Omitted - Highlights: • DMAPbI{sub 3}, TMAPbI{sub 3} and TMAPbBr{sub 3} are reported as new hybrid organic-inorganic compounds. • Crystal structure and optical properties as a function of the number of methyl groups are provided. • Correlation between structure and optical properties are given as a function of tolerance factor.

  6. Broad Wavelength Tunable Robust Lasing from Single-Crystal Nanowires of Cesium Lead Halide Perovskites (CsPbX3, X = Cl, Br, I).

    Science.gov (United States)

    Fu, Yongping; Zhu, Haiming; Stoumpos, Constantinos C; Ding, Qi; Wang, Jue; Kanatzidis, Mercouri G; Zhu, Xiaoyang; Jin, Song

    2016-08-23

    Lead halide perovskite nanowires (NWs) are emerging as a class of inexpensive semiconductors with broad bandgap tunability for optoelectronics, such as tunable NW lasers. Despite exciting progress, the current organic-inorganic hybrid perovskite NW lasers suffer from limited tunable wavelength range and poor material stability. Herein, we report facile solution growth of single-crystal NWs of inorganic perovskite CsPbX3 (X = Br, Cl) and their alloys [CsPb(Br,Cl)3] and a low-temperature vapor-phase halide exchange method to convert CsPbBr3 NWs into perovskite phase CsPb(Br,I)3 alloys and metastable CsPbI3 with well-preserved perovskite crystal lattice and NW morphology. These single crystalline NWs with smooth end facets and subwavelength dimensions are ideal Fabry-Perot cavities for NW lasers. Optically pumped tunable lasing across the entire visible spectrum (420-710 nm) is demonstrated at room temperature from these NWs with low lasing thresholds and high-quality factors. Such highly efficient lasing similar to what can be achieved with organic-inorganic hybrid perovskites indicates that organic cation is not essential for light emission application from these lead halide perovskite materials. Furthermore, the CsPbBr3 NW lasers show stable lasing emission with no measurable degradation after at least 8 h or 7.2 × 10(9) laser shots under continuous illumination, which are substantially more robust than their organic-inorganic counterparts. The Cs-based perovskites offer a stable material platform for tunable NW lasers and other nanoscale optoelectronic devices.

  7. 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.

  8. 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.

  9. Theoretical study of the gas-phase ion pairs SN2 reactions of LiX with CH3SY (X, Y = F, Cl, Br, I)

    Science.gov (United States)

    Gai, Jing-Gang; Ren, Yi

    The gas-phase ion pair SN2 reactions at saturated sulfur LiX + CH3SY ? CH3SX + LiY (X, Y = F, Cl, Br, I) are investigated using the CCSD(T) calculations. The calculated results show that the reactions LiX + CH3SY are exothermic only when the nucleophile is a heavier lithium halide. Central barrier heights are found to depend primarily on the identity of nucleophile LiX, decreasing in the order LiF > LiCl > LiBr > LiI. Another interesting feature of the ion pair reactions at sulfur is the good correlation between the reaction barriers with geometrical looseness of Li bond X and S bond Y bonds in the transition state structures. The data for the reaction barriers show good agreement with the prediction of the Marcus equation and its modification.

  10. Electronic structure and magnetic ordering of the semiconducting chromium trihalides CrCl{sub 3}, CrBr{sub 3}, and CrI{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H; Schwingenschloegl, U [PSE Division, KAUST, Thuwal 23955-6900 (Saudi Arabia); Eyert, V, E-mail: udo.schwingenschlogl@kaust.edu.sa [Centre for Electronic Correlations and Magnetism, University of Augsburg, D-86135 Augsburg (Germany)

    2011-03-23

    We present results from an electronic structure investigation of the chromium halides CrCl{sub 3}, CrBr{sub 3}, and CrI{sub 3}, 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 CrBr{sub 3} as well as CrI{sub 3}. The antiferromagnetic state of CrCl{sub 3} 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 CrCl{sub 3}.

  11. Electronic structure and properties of Cd4As2Br3 and Cd4Sb2I3, analogues of CdSe and CdTe

    Science.gov (United States)

    Roy, Anand; Suchitra; Manjunath, K.; Ahmad, Tokeer; Waghmare, Umesh V.; Rao, C. N. R.

    2017-04-01

    Substitution of aliovalent anions in metal oxides and chalcogenides significantly affects the electronic structure and properties of the materials. Thus, substitution of P3- and Cl- in CdS decreases the band gap and favorably influences the photocatalytic activity. Complete substitution of a trivalent (A3-) and a monovalent (B-) anions in a cadmium chalcogenides, CdX, should give rise to a material of the composition Cd A0.5B0.5 or Cd2AB, but a compound with the composition Cd4P2Cl3 (or Cd2PCl1.5) is obtained in the case of CdS. We have investigated the analogous compounds, Cd4As2Br3 and Cd4Sb2I3, wherein the anions in CdSe and CdTe are substituted by As, Br and Sb, I respectively. These compounds are direct band gap semiconductors with a band gap of 1.8-1.9 eV and a photoluminescence band in the visible region. First-principles calculations show both Cd4As2Br3 and Cd4Sb2I3 to be direct band gap semiconductors. The arsenic bromide is predicted to be photochemically more active for HER than the antimony iodide.

  12. 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.

  13. Molecular clusters Cs3X3 and Cs4X4 (X = Br, I: Quantum chemical study of structure and thermodynamic properties

    Directory of Open Access Journals (Sweden)

    Stanley F. Mwanga

    2016-05-01

    Full Text Available The properties of trimer Cs3X3 and tetramer Cs4X4 (X = Br, I molecules have been studied using DFT with B3LYP5 functional and MP2 and MP4 methods. Two equilibrium geometrical structures of trimers, hexagonal (D3h and “butterfly-shaped” (Cs, and one for tetramers, distorted cubic (Td, are confirmed to exist; geometrical parameters and vibrational spectra are determined. The relative concentration of Cs3X3 isomers has been evaluated; the butterfly-shaped isomer dominates over hexagonal in saturated vapour in a broad temperature range. The dissociation reactions through different channels have been considered and enthalpies of formation ∆fH°(0 of clusters determined: ‒858 ± 20 kJ⋅mol‒1 (Cs3Br3, ‒698 ± 20 kJ⋅mol‒1 (Cs3I3, ‒1270 ± 30 kJ⋅mol‒1 (Cs4Br4 and ‒1045 ± 30 kJ⋅mol‒1 (Cs4I4. The Gibbs free energies ∆rG°(T calculated for the dissociation reactions of trimer and tetramer molecules have indicated that these molecules are resistive in narrow temperature range only and decompose spontaneously with temperature increase with elimination of dimer molecules.

  14. Yukawa sector for LFV in $h\\to \\mu\\tau$ and CP violation in $h\\to \\tau\\tau$

    CERN Document Server

    Hayreter, Alper; Valencia, German

    2016-01-01

    The Higgs boson discovered at the LHC opened a new chapter for particle physics. Its properties need to be studied in detail to distinguish a purely standard model (SM) Higgs boson from one of many scalars in an enlarged Higgs sector. The CMS collaboration has reported a possible lepton flavor violating (LFV) signal $h\\to\\mu\\tau$, which if confirmed, implies that the Higgs sector is larger than in the SM. New physics responsible for this type of decay may, in general, also introduce other observable effects such as charge-parity (CP) violation in $h\\to \\tau\\tau$. We study two types of models that single out the third generation and can induce large $h \\to \\mu\\tau$ rates with different consequences for CP violation in $h \\to \\tau \\tau$. Predictions for the size of the CP violating couplings require knowledge of the lepton Yukawa matrices and we discuss this in the context of two different textures considering all existing constraints.

  15. Clinical evaluation of pixellated NaI:Tl and continuous LaBr 3:Ce, compact scintillation cameras for breast tumors imaging

    Science.gov (United States)

    Pani, R.; Pellegrini, R.; Betti, M.; De Vincentis, G.; Cinti, M. N.; Bennati, P.; Vittorini, F.; Casali, V.; Mattioli, M.; Orsolini Cencelli, V.; Navarria, F.; Bollini, D.; Moschini, G.; Iurlaro, G.; Montani, L.; de Notaristefani, F.

    2007-02-01

    The principal limiting factor in the clinical acceptance of scintimammography is certainly its low sensitivity for cancers sized scintillation camera based on Lanthanum tri-Bromide Cerium-doped crystal (LaBr 3:Ce), that demonstrating superior imaging performances with respect to the dedicated scintillation γ-camera that was previously developed. The proposed detector consists of continuous LaBr 3:Ce scintillator crystal coupled to a Hamamatsu H8500 Flat Panel PMT. One centimeter thick crystal has been chosen to increase crystal detection efficiency. In this paper, we propose a comparison and evaluation between lanthanum γ-camera and a Multi PSPMT camera, NaI(Tl) discrete pixel based, previously developed under "IMI" Italian project for technological transfer of INFN. A phantom study has been developed to test both the cameras before introducing them in clinical trials. High resolution scans produced by LaBr 3:Ce camera showed higher tumor contrast with a detailed imaging of uptake area than pixellated NaI(Tl) dedicated camera. Furthermore, with the lanthanum camera, the Signal-to-Noise Ratio ( SNR) value was increased for a lesion as small as 5 mm, with a consequent strong improvement in detectability.

  16. Photoluminescent mixed ligand complexes of CuX (X = Cl, Br, I) with PPh3 and a polydentate imino-pyridyl ligand - Syntheses, structural variations and catalytic property

    Science.gov (United States)

    Ghorai, Anupam; Mondal, Jahangir; Patra, Goutam K.

    2015-10-01

    Three ternary copper(I) complexes [CuI2Cl2(L1)(PPh3)4] (1), [CuI2Br2(L1) (PPh3)4] (2) and [CuI2(μ-I)2 (μ-L1) (PPh3)2]n (3) have been prepared by reactions of CuX (X = Cl, Br and I) with PPh3 and the polydentate imino-pyridyl ligand L1. These complexes have been characterized by elemental analysis, IR, UV-Vis, NMR and X-ray crystallography. From single crystal structural analysis it has been found that complexes 1 and 2 are homo-dinuclear having non-bridging halide ions whereas complex 3 is a 1-D zig-zag co-ordination polymer containing bridged iodide ions. Complexes 1, 2 and 3 are photoluminescent at room temperature in chloroform whereas ligand L1 is non-emissive. The E½ values of the CuIsbnd CuII couple of 1, 2 and 3 are 0.98 V, 0.92 V and 0.42 V respectively (vs Ag/AgCl in 1 M KCl, scan rate 100 mV s-1). All three complexes function as effective catalysts for the synthesis of 2-substituted benzoxazoles.

  17. New measurements and global analysis of rotational spectra of Cl-, Br-, and I-benzene: Spectroscopic constants and electric dipole moments

    Science.gov (United States)

    Dorosh, Orest; Białkowska-Jaworska, Ewa; Kisiel, Zbigniew; Pszczółkowski, Lech

    2007-12-01

    The data available from rotational spectroscopy for chlorobenzene, bromobenzene, and iodobenzene have been extended by new measurements in the mm-wave region and in supersonic expansion in the cm-wave region. All available ground state measurements have been combined in global fits to derive precise rotational, centrifugal, and nuclear quadrupole coupling constants for the molecules. Rotational transitions in first excited states of the lowest frequency normal modes in bromobenzene and iodobenzene have been assigned and fitted. The values of electric dipole moments for 35Cl-, 79Br-, 81Br-, and I-benzene have been determined from Stark effect measurements on selected hyperfine components in the supersonic expansion spectrum, and are compared with values for several other series of monohalogen molecules.

  18. Room-temperature scintillation properties of cerium-doped REOX (RE=Y, La, Gd, and Lu; X=F, Cl, Br, and I)

    Energy Technology Data Exchange (ETDEWEB)

    Eagleman, Yetta; Bourret-Courchesne, Edith; Derenzo, Stephen

    2010-12-10

    The scintillation properties of cerium-doped oxyhalides following the general formula REOX (RE=Y, La, Gd, and Lu; X=F, Cl, Br, and I) are reported. These materials were synthesized under dry conditions as microcrystalline powders from conventional solid state reactions. The room temperature X-ray excited emission and scintillation decay curves were measured and analyzed for each material. Additionally, the hygroscopic nature of the oxychlorides and oxybromides was compared to that of their corresponding rare earth halides. The yttrium, lanthanum, and gadolinium oxychlorides, and all of the oxybromides and oxyiodides are found to be activated by Ce{sup 3+}. GdOBr doped with 0.5% Ce{sup 3+} has the highest light output with a relative luminosity of about one-half that of LaBr{sub 3}: Ce{sup 3+}. It displays a single exponential decay of 30 ns.

  19. $H\\to \\ell\\ell'$ in the Simplest Little Higgs Model

    CERN Document Server

    Lami, Andrea

    2016-01-01

    Little Higgs Models are promising constructs to solve the hierarchy problem affecting the Higgs boson mass for generic new physics. However, their preservation of lepton universality forbids them to account for the $H\\to\\tau\\mu$ CMS hint and at the same time respect (as they do) the severe limits on $H\\to\\mu e$ inherited from the non-observation of $\\mu\\to e\\gamma$. We compute the predictions of the Simplest Little Higgs Model for the $H\\to \\ell\\ell'$ decays and conclude that the measurement of any of these decays at LHC (even with a much smaller rate than currently hinted) will rule out this model. This result is consistent with our earlier observation of very suppressed lepton flavor violating semileptonic tau decays within this model.

  20. Measurements and modelling of I2, IO, OIO, BrO and NO3 in the mid-latitude marine boundary layer

    Directory of Open Access Journals (Sweden)

    A. Saiz-Lopez

    2006-01-01

    Full Text Available Time series observations of molecular iodine (I2, iodine oxides (IO, OIO, bromine oxide (BrO, and the nitrate radical (NO3 in the mid-latitude coastal marine boundary layer (MBL are reported. Measurements were made using a new long-path DOAS instrument during a summertime campaign at Mace Head on the B3Π(0+u-X1Σ+g electronic transition between 535 and 575 nm. The I2 mixing ratio was found to vary from below the detection limit (~5 ppt up to a nighttime maximum of 93 ppt. Along with I2, observations of IO, OIO and NO3 were also made during the night. Surprisingly, IO and OIO were detected at mixing ratios up to 2.5 and 10.8 ppt, respectively. A model is employed to show that the reaction between I2 and NO3 is the likely nighttime source of these radicals. The BrO mixing ratio varied from below the detection limit at night (~1 ppt to a maximum of 6 ppt in the first hours after sunrise. A bromine chemistry model is used to simulate the diurnal behaviour of the BrO radical, demonstrating the importance of halogen recycling through sea-salt aerosol. In the same campaign a zenith sky DOAS was employed to determine the column density variation of NO3 as a function of solar zenith angle (SZA during sunrise, from which vertical profiles of NO3 through the troposphere were obtained. On several occasions a positive gradient of NO3 was observed over the first 2 km, possibly due to dimethyl sulphide (DMS removing NO3 at the ocean surface.

  1. Mutual Neutralization of Atomic Rare-Gas Cations (Ne+, Ar+, Kr+, Xe+) with Atomic Halide Anions (Cl-, Br-, I-)

    Science.gov (United States)

    2015-01-07

    occur at intersections of the initial ionic potential curve and those describing the interaction between the atoms in their fi- nal states, as in...reactions, the halogen product is formed in excited states with sufficient energy to autoionize to form X+ + e−, Rg+ +X− → Rg +X∗, (3a) → Rg +X+ + e−. (3b...me- ters. The liquid reagents, CCl4 and CF2Br2, are purified via freeze-pump-thaw cycles prior to mixture preparation. The absolute electron density

  2. Efficient syntheses of 5-X-B(10)H(13) Halodecaboranes via the photochemical (X = I) and/or base-catalyzed (X = Cl, Br, I) isomerization reactions of 6-X-B(10)H(13).

    Science.gov (United States)

    Ewing, William C; Carroll, Patrick J; Sneddon, Larry G

    2010-02-15

    High yield syntheses of the 5-X-B(10)H(13) (5X) halodecaboranes have been achieved through the photochemical (X = I) or base-catalyzed (X = Cl, Br, I) isomerization reactions of their 6-X-B(10)H(13) (6X) isomers. 5I was obtained in 80% isolated yield upon the UV photolysis of 6I. Treatment of 6X (X = Cl, Br, I) with catalytic amounts of triethylamine at 60 degrees C led to the formation of 78:22 (Cl), 82:18 (Br), and 86:14 (I) ratio 5X/6X equilibrium mixtures. The 5X isomers were then separated from these mixtures by selective crystallization (Br and I) or column chromatography (Cl), with the supernatant mixtures in each case then subjected to another round of isomerization/separation to harvest a second crop of 5X. The combined isolated yields of pure products after two cycles were 71% 5-Cl-B(10)H(13), 83% 5-Br-B(10)H(13), and 68% 5-I-B(10)H(13). The previously proposed structures of 5-Br-B(10)H(13) and 5-I-B(10)H(13) were crystallographically confirmed. Deprotonation of 6X and 5X with 1,8-bis(dimethylamino)naphthalene (PS) resulted in the formation of [PSH(+)][6X(-)] and [PSH(+)][5X(-)]. Density functional theory-gauge-independent atomic orbital (DFT/GIAO) calculations and crystallographic determinations of [PSH(+)][6Cl(-)] and [PSH(+)][6Cl(-)] confirmed bridge-deprotonation at a site adjacent to the halogen-substituted borons. NMR studies of the 6-Br-B(10)H(13) isomerization induced by stoichiometric amounts of PS showed that following initial deprotonation to form 6-Br-B(10)H(12)(-), isomerization occurred at 60 degrees C to form an equilibrium mixture of 6-Br-B(10)H(12)(-) and 5-Br-B(10)H(12)(-). DFT calculations also showed that the observed 5-X-B(10)H(13)/6-X-B(10)H(13) equilibrium ratios in the triethylamine-catalyzed reactions were consistent with the energetic differences of the 5-X-B(10)H(12)(-) and 6-X-B(10)H(12)(-) anions. These results strongly support a mechanistic pathway for the base-catalyzed 6X to 5X conversions involving the formation and

  3. Temperature dependences of LaBr{sub 3}(Ce), LaCl{sub 3}(Ce) and NaI(Tl) scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Moszynski, M. [Soltan Institute for Nuclear Studies, PL 05-400 Otwock-Swierk (Poland)]. E-mail: marek@ipj.gov.pl; Nassalski, A. [Soltan Institute for Nuclear Studies, PL 05-400 Otwock-Swierk (Poland); Syntfeld-Kazuch, A. [Soltan Institute for Nuclear Studies, PL 05-400 Otwock-Swierk (Poland); Szczesniak, T. [Soltan Institute for Nuclear Studies, PL 05-400 Otwock-Swierk (Poland); Czarnacki, W. [Soltan Institute for Nuclear Studies, PL 05-400 Otwock-Swierk (Poland); Wolski, D. [Soltan Institute for Nuclear Studies, PL 05-400 Otwock-Swierk (Poland); Pausch, G. [Target Systemelectronic GmbH, Koelner Str. 99, D-42651 Solingen (Germany); Stein, J. [Target Systemelectronic GmbH, Koelner Str. 99, D-42651 Solingen (Germany)

    2006-12-01

    The temperature dependence of light output, energy resolution and decay time constants of the light pulses of NaI(Tl), LaCl{sub 3}(Ce) (LaCl{sub 3}) and LaBr{sub 3}(Ce) (LaBr{sub 3}) crystals were measured over the temperature range of -30 to 60 {sup o}C. In the study of the light output, the number of photoelectrons produced by the scintillators in the XP2020 photomultiplier was measured and corrected for by the temperature dependence of the quantum efficiency determined for 360 and 420 nm, respectively. It showed a high stability of the light output of LaBr{sub 3} of about 0.01%/{sup o}C and a comparable uniformity of LaCl{sub 3} at a long peaking time of 12 {mu}s. The well-known thermal instability of NaI(Tl) was confirmed at a short peaking time of 2 {mu}s. However, a much better stability of NaI(Tl) at low temperatures was observed for a long peaking time. The study of the decay of light pulses from LaCl{sub 3} and LaBr{sub 3} crystals confirmed earlier measurements, while NaI(Tl) showed a complex behavior at different temperatures. At low temperatures a strong contribution of a slow component of up to 60% of the total light was observed, while at elevated temperatures a well-known initial slow decay was replaced by a delayed maximum and the slow component became insignificant. The results of the study of energy resolution seem to be correlated with the variation of both the light output and a dependence of the decay time constants of the light pulses at changing temperature. This is particularly interesting in the case of NaI(Tl), where different dependencies of the energy resolution as a function of temperature for different peaking times in the spectroscopy amplifier were found. Tests of the XP2020 PMT itself showed that the thermal instability of the gain of the dynode structure of about-0.4%/{sup o}C is a dominating effect. The opposite effect on an increasing quantum efficiency, partly compensating for the gain instability, was observed above 10 {sup o

  4. Structural, Electronic, and Optical Properties of BiOX1-xYx (X, Y = F, Cl, Br, and I) Solid Solutions from DFT Calculations.

    Science.gov (United States)

    Zhao, Zong-Yan; Liu, Qing-Lu; Dai, Wen-Wu

    2016-08-23

    Six BiOX1-xYx (X, Y = F, Cl, Br, and I) solid solutions have been systematically investigated by density functional theory calculations. BiOCl1-xBrx, BiOBr1-xIx, and BiOCl1-xIx solid solutions have very small bowing parameters; as such, some of their properties increase almost linearly with increasing x. For BiOF1-xYx solid solutions, the bowing parameters are very large and it is extremely difficult to fit the related calculated data by a single equation. Consequently, BiOX1-xYx (X, Y = Cl, Br, and I) solid solutions are highly miscible, while BiOF1-xYx (Y = Cl, Br, and I) solid solutions are partially miscible. In other words, BiOF1-xYx solid solutions have miscibility gaps or high miscibility temperature, resulting in phase separation and F/Y inhomogeneity. Comparison and analysis of the calculated results and the related physical-chemical properties with different halogen compositions indicates that the parameters of BiOX1-xYx solid solutions are determined by the differences of the physical-chemical properties of the two halogen compositions. In this way, the large deviation of some BiOX1-xYx solid solutions from Vegard's law observed in experiments can be explained. Moreover, the composition ratio of BiOX1-xYx solid solutions can be measured or monitored using optical measurements.

  5. 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.

  6. Zero-field splitting and local structure for V2+ ions in CsMgX$_{3} (X=Cl, Br, I)$ crystals

    Indian Academy of Sciences (India)

    Q Wei; Q M Xu; Z Y Yang; D Y Zhang; J G Zhang

    2009-11-01

    The zero-field splitting and local structure for V2+ ions in CsMgX3 $(X = Cl, Br, I)$ crystals are theoretically investigated using complete diagonalization method (CDM) for a $3d^{3}$ ion in trigonal symmetry. Spin–spin (SS) and spin–other-orbit (SOO) interactions are taken into account in addition to the general spin–orbit (SO) interaction. On this basis, using ligand ion displacement model, we find that the ligand ions move away from $C_{3}$-axis, and therefore the local angles in the $V^{2+}$ centres are larger than the angles in the hosts. The results show good agreement with the observed values.

  7. Synthesis, structural and optical characterization of APbX3 (A=methylammonium, dimethylammonium, trimethylammonium; X=I, Br, Cl) hybrid organic-inorganic materials

    Science.gov (United States)

    Mancini, Alessandro; Quadrelli, Paolo; Amoroso, Giuseppe; Milanese, Chiara; Boiocchi, Massimo; Sironi, Angelo; Patrini, Maddalena; Guizzetti, Giorgio; Malavasi, Lorenzo

    2016-08-01

    In this paper we report the synthesis, the crystal structure and the optical response of APbX3 (A=MA, DMA, and TMA; X=I, Br) hybrid organic-inorganic materials including some new phases. We observe that as the cation group increases in size, the optical absorption edge shifts to higher energies with energy steps which are systematic and independent on the anion. A linear correlation between the optical bad gap and the tolerance factor has been shown for the series of samples investigated.

  8. Microwave-induced nucleophilic [18F]fluorination on aromatic rings: synthesis and effect of halogen on [18F]fluoride substitution of meta-halo (F, Cl, Br, I)-benzonitrile derivatives.

    Science.gov (United States)

    Guo, Ning; Alagille, David; Tamagnan, Gilles; Price, Ronald R; Baldwin, Ronald M

    2008-10-01

    The meta-halo-3-methylbenzonitrile derivatives (-F, -Cl, -Br, -I) were synthesized as model compounds to study reactivity towards aromatic nucleophilic substitution. A single-mode microwave system was incorporated into a commercial radiochemical synthetic module for (18)F labeling. Labeling yields of 64% for fluoro-, 13% for bromo- and 9% for chloro-precursors were achieved in DMSO in Br>Cl>I.

  9. Mixed-Halide CH3 NH3 PbI3-x Xx (X=Cl, Br, I) Perovskites: Vapor-Assisted Solution Deposition and Application as Solar Cell Absorbers.

    Science.gov (United States)

    Sedighi, Rahime; Tajabadi, Fariba; Shahbazi, Saeed; Gholipour, Somayeh; Taghavinia, Nima

    2016-08-01

    There have been recent reports on the formation of single-halide perovskites, CH3 NH3 PbX3 (X=Cl, Br, I), by means of vapor-assisted solution processing. Herein, the successful formation of mixed-halide perovskites (CH3 NH3 PbI3-x Xx ) by means of a vapor-assisted solution method at ambient atmosphere is reported. The perovskite films are synthesized by exposing PbI2 film to CH3 NH3 X (X=I, Br, or Cl) vapor. The prepared perovskite films have uniform surfaces with good coverage, as confirmed by SEM images. The inclusion of chlorine and bromine into the structure leads to a lower temperature and shorter reaction time for optimum perovskite film formation. In the case of CH3 NH3 PbI3-x Clx , the optimum reaction temperature is reduced to 100 °C, and the resulting phases are CH3 NH3 PbI3 (with trace Cl) and CH3 NH3 PbCl3 with a ratio of about 2:1. In the case of CH3 NH3 PbI3-x Brx , single-phase CH3 NH3 PbI2 Br is formed in a considerably shorter reaction time than that of CH3 NH3 PbI3 . The mesostructured perovskite solar cells based on CH3 NH3 PbI3 films show the best optimal power conversion efficiency of 13.5 %, whereas for CH3 NH3 PbI3-x Clx and CH3 NH3 PbI3-x Brx the best recorded efficiencies are 11.6 and 10.5 %, respectively.

  10. Coordination Chemistry of Diiodine and Implications for the Oxidation Capacity of the Synergistic Ag(+) /X2 (X=Cl, Br, I) System.

    Science.gov (United States)

    Malinowski, Przemysław J; Himmel, Daniel; Krossing, Ingo

    2016-08-01

    The synergistic Ag(+) /X2 system (X=Cl, Br, I) is a very strong, but ill-defined oxidant-more powerful than X2 or Ag(+) alone. Intermediates for its action may include [Agm (X2 )n ](m+) complexes. Here, we report on an unexpectedly variable coordination chemistry of diiodine towards this direction: (A)Ag-I2 -Ag(A), [Ag2 (I2 )4 ](2+) (A(-) )2 and [Ag2 (I2 )6 ](2+) (A(-) )2 ⋅(I2 )x≈0.65 form by reaction of Ag(A) (A=Al(OR(F) )4 ; R(F) =C(CF3 )3 ) with diiodine (single crystal/powder XRD, Raman spectra and quantum-mechanical calculations). The molecular (A)Ag-I2 -Ag(A) is ideally set up to act as a 2 e(-) oxidant with stoichiometric formation of 2 AgI and 2 A(-) . Preliminary reactivity tests proved this (A)Ag-I2 -Ag(A) starting material to oxidize n-C5 H12 , C3 H8 , CH2 Cl2 , P4 or S8 at room temperature. A rough estimate of its electron affinity places it amongst very strong oxidizers like MF6 (M=4d metals). This suggests that (A)Ag-I2 -Ag(A) will serve as an easily in bulk accessible, well-defined, and very potent oxidant with multiple applications.

  11. Anionic Halomolybdate(III) Chemistry. Tetrahydrofuran Loss from [MoX(3)Y(THF)(2)](-) (X, Y = Cl, Br, I), Preparation and Properties of [Mo(3)X(12)](3)(-) (X = Br, I), and Crystal Structure of the Edge-Sharing Trioctahedral [PPh(4)](3)[Mo(3)I(12)].

    Science.gov (United States)

    Fettinger, James C.; Gordon, John C.; Mattamana, Sundeep P.; O'Connor, Charles J.; Poli, Rinaldo; Salem, Ghadi

    1996-12-04

    By interaction of MoX(3)(THF)(3) with [Cat]X in THF, the salts [Cat][MoX(4)(THF)(2)] have been synthesized [X = I, Cat = PPh(4), NBu(4), NPr(4), (Ph(3)P)(2)N; X = Br, Cat = NBu(4), PPh(4) (Ph(3)P)(2)N]. Mixed-halide species [MoX(3)Y(THF)(2)](-) (X, Y = Cl, Br, I) have also been generated in solution and investigated by (1)H-NMR. When the tetraiodo, tetrabromo, and mixed bromoiodo salts are dissolved in CH(2)Cl(2), clean loss of all coordinated THF is observed by (1)H-NMR. On the other hand, [MoCl(4)(THF)(2)](-) loses only 1.5 THF/Mo. The salts [Cat](3)[Mo(3)X(12)] (X = Br, I) have been isolated from [Cat][MoX(4)(THF)(2)] or by running the reaction between MoX(3)(THF)(3) and [Cat]X directly in CH(2)Cl(2). The crystal structure of [PPh(4)](3)[Mo(3)I(12)] exhibits a linear face-sharing trioctahedron for the trianion: triclinic, space group P&onemacr;; a = 11.385(2), b = 12.697(3), c = 16.849(2) Å; alpha = 76.65(2), beta = 71.967(12), gamma = 84.56(2) degrees; Z = 1; 431 parameters and 3957 data with I > 2sigma(I). The metal-metal distance is 3.258(2) Å. Structural and magnetic data are consistent with the presence of a metal-metal sigma bond order of (1)/(2) and with the remaining 7 electrons being located in 7 substantially nonbonding orbitals. The ground state of the molecule is predicted to be subject to a Jahn-Teller distortion, which is experimentally apparent from the nature of the thermal ellipsoid of the central Mo atom. The [Mo(3)X(12)](3)(-) ions reacts with phosphines (PMe(3), dppe) to form products of lower nuclearity by rupture of the bridging Mo-X bonds.

  12. Measurements of the work function of single-walled carbon nanotubes encapsulated by AgI, AgCl, and CuBr using Kelvin probe technique with different kinds of probes

    Energy Technology Data Exchange (ETDEWEB)

    Zhukov, A. A., E-mail: azhukov@issp.ac.ru [Russian Academy of Science, Institute of Solid State Physics (Russian Federation); Chernysheva, M. V.; Eliseev, A. A. [Moscow State University, Department of Materials Science (Russian Federation)

    2016-07-15

    We report the results on the measurements of the work function of single-walled carbon nanotubes encapsulated by Agl (AgI@SWCNT), AgCl (AgCl@SWCNT), and CuBr (CuBr@SWCNT) by the local Kelvin probe technique. We found the values of the work function of tubes encapsulated with AgI and AgCl (Φ(AgI@SWCNT) = 5.08 ± 0.02, Φ(AgCl@SWCNT) = 5.10 ± 0.02 eV) to exceed substantially that of pristine carbon nanotubes, and the value of the work function of carbon nanotubes encapsulated with CuBr is Φ(CuBr@SWCNT) = 4.89 ± 0.03 (eV). The measurements are carried out using different kinds of microscope probes including multi-walled carbon nanotube tips.

  13. Near-infrared to visible upconversion in Er3+ doped Cs3Lu2Cl9, Cs3Lu2Br9, and Cs3Y2I9 excited at 1.54 µm

    NARCIS (Netherlands)

    Lüthi, Stefan R.; Pollnau, Markus; Güdel, Hans U.; Hehlen, Markus P.

    1999-01-01

    A detailed study of upconversion processes in Cs3Er2X9 (X = Cl, Br, I) crystals and in the diluted systems Cs3Lu2Cl9:1% Er3+, Cs3Lu2Br9:1% Er3+, and Cs3Y2I9:1% Er3+ is presented. Efficient two-, three-, and four-step upconversion excitation along the sequence 4I15/2 4I13/2 4I9/2 4S3/2 2H9/2

  14. Relevance of weak intermolecular forces on the supramolecular structure of free or DMSO solvated 5-(4-X-benzylidene)rhodanines (X = F, Cl, Br, I)

    Science.gov (United States)

    Casas, José S.; Castaño, M. Victoria; Couce, María D.; Sánchez, Agustín; Sordo, José; Torres, M. Dolores; Vázquez, Saulo A.; Vázquez-López, Ezequiel M.

    2016-09-01

    The rhodanines of the title (Xp-Rhod, X = F, Cl, Br, I) were synthesized and characterized in solid state and in solution. The crystal structures of the four compounds show different supramolecular organizations. In the F-, Cl- and Br-derivatives, a R22(8) (CSNH)2 ring forms via Nsbnd H⋯S hydrogen bonds between two neighbouring molecules to give dimers. The I-derivative is also dimeric, but exhibits R22(8) (CONH)2 rings. The two type of dimers are associated in a variety of structures through hydrogen bonding, π-stacking, Csbnd H⋯π interactions and halogen bonding. These interactions were analysed from a crystallographic point of view and their relative relevance was explored using DFT calculations. The effect produced on all these interactions by the incorporation of DMSO molecules to the lattice was analysed by comparing the crystal structures of Xp-Rhod compounds and those of corresponding Xp-RhodṡDMSO solvates.

  15. The halogen (F, Cl, Br, I) and H2O systematics of Samoan lavas: Assimilated-seawater, EM2 and high-3He/4He components

    Science.gov (United States)

    Kendrick, Mark A.; Jackson, Matthew G.; Hauri, Erik H.; Phillips, David

    2015-01-01

    The Samoan mantle plume samples two or more mantle components including an extreme EM2 composition with 87Sr/86Sr > 0.720 and a primitive component with high 3He/4He. The high 87Sr/86Sr melts have a unique potential to constrain the composition of the EM2 mantle end-member that is commonly attributed to subduction recycling. However, a previous study of H2O, CO2, S, F and Cl in Samoan glasses was hampered by the presence of unresolved assimilated sea water. The current study builds on the earlier work by extending the volatile database to include the trace halogens Br and I, and reporting new volatile data for additional glasses with 87Sr/86Sr up to 0.7125 and 3He/4He up to 15 Ra (Ra is the atmospheric 3He/4He ratio of 1.39 ×10-6). The selected glasses with MgO of 4.0 to 6.5 wt.% have CO2 concentrations of 4 to 200 ppm that reflect degassing of CO2 on the seafloor. The glasses contain 0.7-1.9 wt.% H2O, 880-1870 ppm F, 490-1790 ppm Cl, 1.9-7.2 ppm Br, 19-130 ppb I and 0.6-1.7 wt.% K. Correlations between the concentrations of these elements suggest the melts retain H2O concentrations close to pre-degassing values and demonstrate the melts have been variably affected by assimilation of seawater-derived brines. The brines are indicated to have had salinities of 55 ± 15 wt.% salt, F/Cl ratios close to seawater (e.g. calculated the melts assimilated brine fractions of 0 to 0.45 wt.%, which contributed up to ∼30% of the total H2O and up to ∼70% of the total Cl in the melts. After accounting for the effects of brine assimilation, the Samoan melts are suggested to have a fairly constant magmatic Cl/K of 0.05 ± 0.2, which is lower than the median MORB value. Assimilation-corrected H2O/Ce values are not correlated with 87Sr/86Sr, but the sample with the highest 87Sr/86Sr of 0.7125 has an assimilation-corrected H2O/Ce of 83 ± 3, that is significantly lower than typical MORB values of 150-300. These data confirm that the Samoan EM2 source is depleted in H2O, and

  16. Halogen Bonding or Hydrogen Bonding between 2,2,6,6-Tetramethyl-piperidine-noxyl Radical and Trihalomethanes CHX3 (X=Cl, Br, I)

    Institute of Scientific and Technical Information of China (English)

    Xiao-ran Zhao; Xue Pang; Xiao-qing Yan; Wei-jun Jin

    2013-01-01

    The halogen and hydrogen bonding complexes between 2,2,6,6-tetramethylpiperidine-noxyl and trihalomethanes (CHX3,X=Cl,Br,I) are simulated by computational quantum chemistry.The molecular electrostatic potentials,geometrical parameters and interaction energy of halogen and hydrogen bonding complexes combined with natural bond orbital analysis are obtained.The results indicate that both halogen and hydrogen bonding interactions obey the order Cl<Br<I,and hydrogen bonding is stronger than the corresponding halogen bond ing.So,hydrogen bonding complexes should be dominant in trihalomethanes.However,it is possible that halogen bonding complex is competitive,even preponderant,in triiodomethane due to the similar interaction energy.This work might provide useful information on specific solvent effects as well as for understanding the mechanism of nitroxide radicals as a bioprobe to interact with the halogenated compounds in biological and biochemical fields.

  17. Theoretical X-ray production cross sections at incident photon energies across Li (i=1-3) absorption edges of Br

    Science.gov (United States)

    Puri, Sanjiv

    2015-08-01

    The X-ray production (XRP) cross sections, σLk (k = l, η, α, β6, β1, β3, β4, β9,10, γ1,5, γ2,3) have been evaluated at incident photon energies across the Li(i=1-3) absorption edge energies of 35Br using theoretical data sets of different physical parameters, namely, the Li(i=1-3) sub-shell the X-ray emission rates based on the Dirac-Fock (DF) model, the fluorescence and Coster Kronig yields based on the Dirac-Hartree-Slater (DHS) model, and two sets of the photoionisation cross sections based on the relativistic Hartree-Fock-Slater (RHFS) model and the Dirac-Fock (DF) model, in order to highlight the importance of electron exchange effects at photon energies in vicinity of absorption edge energies.

  18. 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.

  19. Characterization of PARIS LaBr$_3$(Ce)-NaI(Tl) phoswich detectors upto $E_\\gamma$ $\\sim$ 22 MeV

    CERN Document Server

    Ghosh, C; Pillay, R G; K., Anoop; Dokania, N; Pal, Sanjoy; Pose, M S; Mishra, G; Rout, P C; Kumar, Suresh; Pandit, Deepak; Mondal, Debasish; Pal, Surajit; Banerjee, S R; Napiorkowski, Paweł J; Dorvaux, Oliver; Kihel, S; Mathieu, C; Maj, A

    2016-01-01

    In order to understand the performance of the PARIS (Photon Array for the studies with Radioactive Ion and Stable beams) detector, detailed characterization of two individual phoswich (LaBr$_3$(Ce)-NaI(Tl)) elements has been carried out. The detector response is investigated over a wide range of $E_{\\gamma}$ = 0.6 to 22.6 MeV using radioactive sources and employing $^{11}B(p,\\gamma)$ reaction at $E_p$ = 163 keV and $E_p$ = 7.2 MeV. The linearity of energy response of the LaBr$_3$(Ce) detector is tested upto 22.6 MeV using three different voltage dividers. The data acquisition system using CAEN digitizers is set up and optimized to get the best energy and time resolution. The energy resolution of $\\sim$ 2.1% at $E_\\gamma$ = 22.6~MeV is measured for configuration giving best linearity upto high energy. Time resolution of the phoswich detector is measured with $^{60}$Co source after implementing CFD algorithm for the digitized pulses and is found to be excellent (FWHM $\\sim$ 315~ps). In order to study the effect...

  20. Magnetic transitions in botallackite-structure Cu{sub 2}(OH){sub 3}Br and Cu{sub 2}(OH){sub 3}I

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, X.G., E-mail: zheng@cc.saga-u.ac.j [Department of Physics, Faculty of Science and Engineering, Saga University, Saga 840-8502 (Japan); Department of Physics, School of Engineering, Saga University, Saga 840-8502 (Japan); Yamashita, T.; Hagihala, M.; Fujihala, M. [Department of Physics, School of Engineering, Saga University, Saga 840-8502 (Japan); Kawae, T. [Department of Applied Quantum Physics, Faculty of Engineering, Kyushu University, Fukuoka 812-8581 (Japan)

    2009-04-15

    The deformed pyrochlore lattice compound clinoatacamite, Cu{sub 2}(OH){sub 3}Cl, shows intriguing magnetism and 1/4 substitution of Cu with nonmagnetic Zn leads to the two-dimensional kagome lattice ZnCu{sub 3}Cl{sub 2}(OH){sub 6} that exhibits spin liquid behaviour. These findings renewed interest in botallackite Cu{sub 2}(OH){sub 3}Cl, which is a polymorphous structure of clinoatacamite Cu{sub 2}(OH){sub 3}Cl possessing a two-dimensional triangular lattice. The present work investigates the effect of halogen ions on the magnetic transitions in the botallackite structure. Similar to the antiferromagnetic Cu{sub 2}(OH){sub 3}Cl (T{sub N}=7.2 K), Cu{sub 2}(OH){sub 3}Br and Cu{sub 2}(OH){sub 3}I both showed antiferromagnetic transitions at T{sub N}=10 and 14 K, respectively. Long-range order also exists in Cu{sub 2}(OH){sub 3}Br as exemplified by the muSR study. The experimental results suggest that the magnetic coupling on the triangular lattice is dominated by the super-exchange interaction through the halogen ions. Further detailed comparison studies on these botallackite-structure compounds are expected to clarify the spin configuration on this triangular lattice.

  1. 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 = O2 , S, Se, Te, I2 , Br2 ) 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 = O2 , S, Se, Te, I2 , Br2 ) 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-O2 (S) batteries. In terms of the emerging Li-X (Se, Te, I2 , Br2 ) 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-I2 (Br2 ) 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 = O2 , S, Se, Te, I2 , Br2 ) batteries is presented. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Two-dimensional rectangular tantalum carbide halides TaCX (X = Cl, Br, I): novel large-gap quantum spin Hall insulators

    Science.gov (United States)

    Zhou, Liujiang; Shi, Wujun; Sun, Yan; Shao, Bin; Felser, Claudia; Yan, Binghai; Frauenheim, Thomas

    2016-09-01

    Quantum spin Hall (QSH) insulates exist in special two-dimensional (2D) semiconductors, possessing the quantized spin-Hall conductance that are topologically protected from backscattering. Based on the first-principles calculations, we predict a novel family of QSH insulators in 2D tantalum carbide halides TaCX (X = Cl, Br, and I) with unique rectangular lattice and large direct energy gaps. The mechanism for 2D QSH effect originates from an intrinsic d-d band inversion in the process of chemical bonding. Further, stain and intrinsic electric field can be used to tune the electronic structure and enhance the energy gap. TaCX nanoribbon, which has the single-Dirac-cone edge states crossing the bulk band gap, exhibits a linear dispersion with a high Fermi velocity comparable to that of graphene. These 2D materials with considerable nontrivial gaps promise great application potential in the new generation of dissipationless electronics and spintronics.

  3. Theoretical study of the reactivity trends in the Cl-abstraction reactions of CHCl3 + CHX·−/CX$_{2}^{·−}$ (X = Cl, Br and I)

    Indian Academy of Sciences (India)

    Jun Xi Liang; Zhi Yuan Geng; Yong Cheng Wang

    2011-09-01

    To better understand how and to what extent the halosubstituted carbene radical anions effect the chlorine abstraction of CHCl3, a detailed theoretical investigation has been performed at the UMP2/6-311++G (d, p)/RECP level of theory. The model system CHCl3+CHX·−/CX$^{·−}_{2}$ (X = Cl, Br, and I) has been chosen for the present study. According to the detailed discussions of geometries and energetics of the optimized stationary points, our theoretical findings suggest that the Cl-abstraction reactions by CHX·− are energetically favourable, indicating the less massive substitution X in CHX·− the easier abstraction reaction, as compared to those by CX$^{·−}_{2}$, which are energetically unfavourable and would be endothermic.

  4. 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.

  5. A 3D-analysis of cluster formation and dynamics of the X(-)-benzene (X = F, Cl, Br, I) ionic dimer solvated by Ar atoms.

    Science.gov (United States)

    Albertí, Margarita; Huarte-Larrañaga, Fermín; Aguilar, Antonio; Lucas, José M; Pirani, Fernando

    2011-05-14

    The specific influence of X(-) ions (X = F,Cl, Br, I) in the solvation process of halide-benzene (X(-)-Bz) ionic heterodimers by Ar atoms is investigated by means of molecular dynamic (MD) simulations. The gradual evolution from cluster rearrangement to solvation dynamics is discussed by considering ensembles of n (n = 1-15 and n = 30) Ar atoms around the X(-)-Bz stable ionic dimers. The potential energy surfaces employed are based on an atom/ion-atom and atom/ion-bond decomposition, which has been developed previously by some of the authors. The outcome of the dynamics is analyzed by employing radial distribution functions (RDF) and tridimensional (3D) probability densities.

  6. Nature of the band gap of halide perovskites 3 (=CH3NH3, Cs; =Sn, Pb; =Cl, Br, I):First-principles calculations

    Institute of Scientific and Technical Information of China (English)

    袁野; 徐闰; 徐海涛; 洪峰; 徐飞; 王林军

    2015-01-01

    The electronic structures of cubic structure of ABX3(A=CH3NH3, Cs;B=Sn, Pb;X=Cl, Br, I) are analyzed by den-sity functional theory using the Perdew–Burke–Ernzerhof exchange–correlation functional and using the Heyd–Scuseria–Ernzerhof hybrid functional. The valence band maximum (VBM) is found to be made up by an antibonding hybridization of B s and X p states, whereas bands made up by theπ antibonding of B p and X p states dominates the conduction band minimum (CBM). The changes of VBM, CBM, and band gap with ion B and X are then systematically summarized. The natural band offsets of ABX3 are partly given. We also found for all the ABX3 perovskite materials in this study, the bandgap increases with an increasing lattice parameter. This phenomenon has good consistency with the experimental results.

  7. Ab initio design of CsSn(XxY 1−x3 (X and Y = Cl, Br, and I perovskites for photovoltaics

    Directory of Open Access Journals (Sweden)

    Arpan Krishna Deb

    2015-07-01

    Full Text Available Ab initio calculations on CsSnX3 perovskites and mixed halides CsSn(XxY 1−x3, X and Y = I, Cl, and Br, show that all of them have a direct band gap of ∼1 eV which can be tuned by varying the compositions of X and Y. The optimized supercells are tetragonal, orthorhombic or monoclinic. The top of the valence band arises from hybridization of Sn 4s and halogen p valence orbitals while the bottom of the conduction band has predominantly Sn p character. Similar to organo-metallic lead halides this is expected to facilitate p-p optical transitions that are highly favourable for photoabsorption. Our results suggest that these inorganic perovskites have the desired features to achieve high efficiency of photo-response with appropriate combination of halogens.

  8. Reaction of allene esters with Selectfluor/TMSX (X = I, Br, Cl and Selectfluor/NH4SCN: Competing oxidative/electrophilic dihalogenation and nucleophilic/conjugate addition

    Directory of Open Access Journals (Sweden)

    A. Srinivas Reddy

    2015-09-01

    Full Text Available Reaction of benzyl and ethyl allenoates with TMSX (X = I, Br, Cl and with NH4SCN were investigated in MeCN, DMF, and in imidazolium ionic liquids [BMIM][NTf2] and [BMIM][PF6] as solvent, in the presence and absence of Selectfluor. Comparative product analysis studies demonstrate that the ability of Selectflour to promote oxidative/electrophilic dihalogenation/dithiocyanation with TMSX/NH4SCN (as observed previously for 1-arylallenes is diminished in allenoates, most significantly in reactions with TMSCl, and essentially disappearing in reactions with NH4SCN, in favor of nucleophilic/conjugate addition. The study underscores the contrasting reactivity patterns in 1-arylallenes and allenoates toward electrophilic and nucleophilic additions in halofunctionalization with TMSX/Selectfluor and thiocyanation reactions with NH4SCN/Selectfluor. These competing pathways are influenced by the nature of the anion, allene structure, and the choice of solvent.

  9. Theoretical study of the gas-phase SN2 reactions of X- with CH3OY (X, Y = Cl, Br, I)

    Science.gov (United States)

    Gai, Jing-Gang; Ren, Yi

    The gas-phase nucleophilic substitution reactions at saturated oxygen X- + CH3OY (X, Y D Cl, Br, I) have been investigated at the level of CCSD(T)/6-311+G(2df,p)//B3LYP/6-311+G(2df,p). The calculated results indicate that X- preferably attacks oxygen atom of CH3OY via a SN2 pathway. The central barriers and overall barriers are respectively in good agreement with both the predictions of Marcus equation and its modification, respectively. Central barrier heights (?HXY? and ?HYX?) correlate well with the charges (Q) of the leaving groups (Y), Wiberg bond orders (BO) and the elongation of the bonds (O―Y and O―X) in the transition structures.

  10. Antiferromagnetism in a Family of S = 1 Square Lattice Coordination Polymers NiX2(pyz)2 (X = Cl, Br, I, NCS; pyz = Pyrazine).

    Science.gov (United States)

    Liu, Junjie; Goddard, Paul A; Singleton, John; Brambleby, Jamie; Foronda, Francesca; Möller, Johannes S; Kohama, Yoshimitsu; Ghannadzadeh, Saman; Ardavan, Arzhang; Blundell, Stephen J; Lancaster, Tom; Xiao, Fan; Williams, Robert C; Pratt, Francis L; Baker, Peter J; Wierschem, Keola; Lapidus, Saul H; Stone, Kevin H; Stephens, Peter W; Bendix, Jesper; Woods, Toby J; Carreiro, Kimberly E; Tran, Hope E; Villa, Cecelia J; Manson, Jamie L

    2016-04-01

    The crystal structures of NiX2(pyz)2 (X = Cl (1), Br (2), I (3), and NCS (4)) were determined by synchrotron X-ray powder diffraction. All four compounds consist of two-dimensional (2D) square arrays self-assembled from octahedral NiN4X2 units that are bridged by pyz ligands. The 2D layered motifs displayed by 1-4 are relevant to bifluoride-bridged [Ni(HF2)(pyz)2]EF6 (E = P, Sb), which also possess the same 2D layers. In contrast, terminal X ligands occupy axial positions in 1-4 and cause a staggered packing of adjacent layers. Long-range antiferromagnetic (AFM) order occurs below 1.5 (Cl), 1.9 (Br and NCS), and 2.5 K (I) as determined by heat capacity and muon-spin relaxation. The single-ion anisotropy and g factor of 2, 3, and 4 were measured by electron-spin resonance with no evidence for zero-field splitting (ZFS) being observed. The magnetism of 1-4 spans the spectrum from quasi-two-dimensional (2D) to three-dimensional (3D) antiferromagnetism. Nearly identical results and thermodynamic features were obtained for 2 and 4 as shown by pulsed-field magnetization, magnetic susceptibility, as well as their Néel temperatures. Magnetization curves for 2 and 4 calculated by quantum Monte Carlo simulation also show excellent agreement with the pulsed-field data. Compound 3 is characterized as a 3D AFM with the interlayer interaction (J⊥) being slightly stronger than the intralayer interaction along Ni-pyz-Ni segments (J(pyz)) within the two-dimensional [Ni(pyz)2](2+) square planes. Regardless of X, J(pyz) is similar for the four compounds and is roughly 1 K.

  11. Dehydrohalogenation and Dehydration Reactions of i-C3H7Br and i-C3H7OH by Sodium Ions Studied by Guided Ion Beam Techniques and Quantum Chemical Methods.

    Science.gov (United States)

    López, E; Lucas, J M; de Andrés, J; Albertí, M; Bofill, J M; Aguilar, A

    2016-07-14

    Dehydrohalogenation and dehydration reactions of gas-phase i-C3H7Br and i-C3H7OH molecules induced by collision with Na(+), all participants being in their electronic ground state, were studied experimentally in our laboratory using a radiofrequency-guided ion beam apparatus and covering the 0.10-10.00 eV center of mass (CM) energy range. In Na(+) + i-C3H7Br collisions the formation of [C3H6-Na](+) and [HBr-Na](+) by dehydrohalogenation was observed and quantified, as well as that of the ion-molecule adduct [Na-i-C3H7Br](+) together with its decomposition products C3H7(+) and NaBr. In Na(+) + i-C3H7OH collisions the dehydration product [H2O-Na](+) was also found, while [C3H6-Na](+) was hardly detected. Moreover, the [Na-i-C3H7OH](+) adduct formation as well as its decomposition into C3H7(+) and NaOH were also quantified. For all these processes, absolute reaction cross sections were measured as a function of the CM collision energy. From measured excitation functions, rate constants for the formation of [C3H6-Na](+), [HBr-Na](+), and [H2O-Na](+) at 303 K were obtained. Complementing the experiments, exhaustive ab initio structure calculations at the MP2 level of theory were performed, giving information on the most relevant features of the potential energy surfaces (PESs) where the dehydrohalogenation, dehydration, and decomposition reactions take place adiabatically for both collision systems. On these PESs different stationary points associated with potential energy minima and transition state barriers were characterized, and their connectivity was ensured using the intrinsic-reaction-coordinate method. The main topology features of the ab initio calculated PESs allowed a qualitative interpretation of the experimental data also exposing the role of the sodium ion as a catalyst in elimination reactions.

  12. Stable and low-cost mesoscopic CH3NH3PbI2 Br perovskite solar cells by using a thin poly(3-hexylthiophene) layer as a hole transporter.

    Science.gov (United States)

    Zhang, Meng; Lyu, Miaoqiang; Yu, Hua; Yun, Jung-Ho; Wang, Qiong; Wang, Lianzhou

    2015-01-02

    Mesoscopic perovskite solar cells using stable CH3 NH3 PbI2 Br as a light absorber and low-cost poly(3-hexylthiophene) (P3HT) as hole-transporting layer were fabricated, and a power conversion efficiency of 6.64 % was achieved. The partial substitution of iodine with bromine in the perovskite led to remarkably prolonged charge carrier lifetime. Meanwhile, the replacement of conventional thick spiro-MeOTAD layer with a thin P3HT layer has significantly reduced the fabrication cost. The solar cells retained their photovoltaic performance well when they were exposed to air without any encapsulation, presenting a favorable stability. The combination of CH3 NH3 PbI2 Br and P3HT may render a practical and cost-effective solid-state photovoltaic system. The superior stability of CH3 NH3 PbI2 Br is also promising for other photoconversion applications.

  13. A Valence Bond Method Study for SN2 Reaction X-l+CH3Xr→XlCH3+X-r(Xl=Xr=F, Cl, Br, I)%SN2反应X-l+CH3XrXlCH3+X-r(Xl=Xr=F, Cl, Br, I)的价键方法研究

    Institute of Scientific and Technical Information of China (English)

    陈衍芬; 宋凌春; 吴玮; 张乾二

    2003-01-01

    应用最近发展的价键组态相互作用(VBCI)方法计算了SN2反应X-l+CH3Xr→XlCH3+X-r(Xl=Xr=F, Cl, Br, I)的反应能垒和价键相关参数. 计算结果表明, VBCI能垒与采用分子轨道理论的CCSD(T)方法计算的能垒相一致. 讨论了SN2反应的反应参数.

  14. Measuring the scintillation decay time for different energy depositions in NaI:Tl, LSO:Ce and CeBr{sub 3} scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Swiderski, Lukasz, E-mail: lukasz.swiderski@ncbj.gov.pl; Moszynski, Marek; Syntfeld-Kazuch, Agnieszka; Szawlowski, Marek; Szczesniak, Tomasz

    2014-06-01

    This study presents a simple experimental setup for precise inspection of scintillation decay characteristics as a function of the energy deposited in scintillators. The results are discussed for NaI:Tl, LSO:Ce and CeBr{sub 3} crystals. The tested samples were coupled to a fast response R5320 photomultiplier from Hamamatsu. The decay time constants were measured by fitting the anode pulses of the PMT registered directly with a TDS5054B digital oscilloscope from Tektronix. Simple analog electronics composed of timing single channel analyzers, gate generators and coincidence/logic unit was used for selection of the deposited energy converted into light within the scintillator, and for triggering the scope to register relevant scintillation pulses. High precision of the experimental setup allowed for registration of non-proportionality curves for all samples. Moreover, non-proportionality was measured for fast and slow decay mode of NaI:Tl separately. The measurement was also used for inspection of possible differences in the pulse shapes originating from Compton scattering events and photoabsorption.

  15. On the possibility to detect the Higgs decay $H\\to b\\bar b$ in the associated $Z + b\\bar b$ production at the LHC

    CERN Document Server

    Lipatov, A V

    2015-01-01

    We investigate the possibility to detect the scalar Higgs boson decay $H\\to b\\bar b$ in the associated $Z$ and $b\\bar b$ production at the LHC using the $k_T$-factorization QCD approach. Our consideration is based on the off-shell (i.e. depending on the transverse momenta of initial quarks and gluons) production amplitudes of $q^* \\bar q^* \\to Z H \\to Z q^\\prime \\bar q^\\prime$, $q^* \\bar q^* \\to Z q^\\prime \\bar q^\\prime$ and $g^* g^* \\to Z q^\\prime \\bar q^\\prime$ partonic subprocesses supplemented with the Catani-Ciafoloni-Fiorani-Marchesini (CCFM) dynamics of parton densities in a proton. We argue that the $H \\to b\\bar b$ signal could be observed at large transverse momenta near Higgs boson peak despite the overwhelming QCD background, and point out an important role of angular correlations between the produced $Z$ boson and $b$-quarks.

  16. Librational modes of the water molecules in barium and strontium halide monohydrates, MX 2 · 1H 2O (M = Ba, Sr; X = Cl, Br, I)

    Science.gov (United States)

    Lutz, H. D.; Christian, H.

    1983-09-01

    The IR and Raman spectra of the isotypic alkaline earth halide monohydrates, MX 2 · 1H 2O, with M = Sr, Ba and X = Cl, Br, I, and of deuterated samples are presented for the range 200-700 cm -1 and discussed in terms of normal modes, assignment, coupling, correlation with structure data, and temperature dependence of both the H 2O (D 2O) and the HDO librational modes. The normal modes of the out-of-plane librations of HDO molecules are of the wagging and twisting type rather than H and D out-of-plane vibrations [4], at least for water molecules with C2v or nearly C2v symmetry. Thus the observed H 2O/HDO isotopic shifts can be used as a criterion for assigning the H 2O librations. The librational modes of the halide monohydrates (with tetrahedrally coordinated water oxygen atoms) are found in the order ν Rγ ≫ ν Rt ≫ ν Rr. The intensities of the IR and Raman spectra are in the order Rγ ≫ Rr ≫ Rt (or ˜ Rt in the case of strongly distorted H 2O molecules) and Rt ≫ Rr ≫ Rγ, respectively. Correlations of the H 2O librational modes with structural or bonding data are restricted by frequency shifts due to vibrational coupling and by the fact that the oxygen and the hydrogen atoms of the water molecules are generally affected in a different manner by bond interactions. However, in the case of the twisting vibrations, there are clear correlations with both the size of the metal ions, i.e. increase of ν Rt with decreasing size, and the intermolecular bonding of the hydrogen atoms, as shown by the OH stretching frequencies, i.e. increase of ν Rt with decreasing ν OH.

  17. The Dewar-Chatt-Duncanson model reversed Bonding analysis of group-10 complexes [(PMe3)2M-EX3] (M = Ni, Pd, Pt;; E = B, Al, Ga, In, Tl;; X = H, F, Cl, Br, I)

    National Research Council Canada - National Science Library

    Haunschild, Robin; Hillebrecht, Pierre; Goedecke, Catharina; Uhlemann, Till; Frenking, Gernot

    2009-01-01

    ...-acceptor complexes [(PMe 3 ) 2 M-EX 3 ] with X = H, F, Cl, Br, I;; E = B, Al, Ga, In, Tl; and M = Ni, Pd, Pt. The nature of the metal-ligand bond was investigated with an energy decomposition analysis...

  18. CH3 NH3 PbBr3 -CH3 NH3 PbI3 Perovskite-Perovskite Tandem Solar Cells with Exceeding 2.2 V Open Circuit Voltage.

    Science.gov (United States)

    Heo, Jin Hyuck; Im, Sang Hyuk

    2016-07-01

    Perovskite-perovskite tandem solar cells with open-circuit voltages of over 2.2 V are reported. These cost-effective, solution-processible perovskite hybrid tandem solar cells with high open-circuit voltages are fabricated by the simple lamination of a front planar MAPbBr3 perovskite cell and a back MAPbI3 planar perovskite solar cell.

  19. Influence of the reduced dimensionality on the thermodynamical and electrical properties of photosensitive BiOX (X = Cl, Br, and I) semiconductors

    Science.gov (United States)

    Lotnyk, D.; Komanický, V.; Feher, A.; Bunda, V.

    2016-12-01

    The influence of the layered structure on the temperature dependencies of the specific heat, thermal conductivity, and electric resistivity of photosensitive bismuth oxyhalides BiOX (X = Cl, Br and I) single crystals were investigated in the temperature range 2 K ≤ T ≤ 300 K. The low temperature specific heat data for BiOX demonstrated the presence of two-dimensional behavior with increased anisotropy for the BiOI sample. Moreover, the thermal conductivity values for BiOI are three times higher than for BiOCl and BiOBr, and this observation is consistent with increased anisotropy arising from the contribution of optical out-of-plane phonons. The influence of green (λ = 532 nm) and red (λ = 640 nm) laser excitations on the electrical conductivity properties has been investigated. Each photoconductivity curve reveals transitions from low to high sensitivity. The depletion temperature region for BiOX single crystals corresponds to the peak in temperature dependence of the charge carrier mobility.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Ozone Depletion Potential of CH3Br

    Science.gov (United States)

    Sander, Stanley P.; Ko, Malcolm K. W.; Sze, Nien Dak; Scott, Courtney; Rodriquez, Jose M.; Weisenstein, Debra K.

    1998-01-01

    The ozone depletion potential (ODP) of methyl bromide (CH3Br) can be determined by combining the model-calculated bromine efficiency factor (BEF) for CH3Br and its atmospheric lifetime. This paper examines how changes in several key kinetic data affect BEF. The key reactions highlighted in this study include the reaction of BrO + H02, the absorption cross section of HOBr, the absorption cross section and the photolysis products of BrON02, and the heterogeneous conversion of BrON02 to HOBR and HN03 on aerosol particles. By combining the calculated BEF with the latest estimate of 0.7 year for the atmospheric lifetime of CH3Br, the likely value of ODP for CH3Br is 0.39. The model-calculated concentration of HBr (approximately 0.3 pptv) in the lower stratosphere is substantially smaller than the reported measured value of about I pptv. Recent publications suggested models can reproduce the measured value if one assumes a yield for HBr from the reaction of BrO + OH or from the reaction of BrO + H02. Although the DeAlore et al. evaluation concluded any substantial yield of HBr from BrO + HO2 is unlikely, for completeness, we calculate the effects of these assumed yields on BEF for CH3Br. Our calculations show that the effects are minimal: practically no impact for an assumed 1.3% yield of HBr from BrO + OH and 10% smaller for an assumed 0.6% yield from BrO + H02.

  5. Analyses of the tilde{A}-tilde{X} Electronic Transitions of the CH{_2}XOO{\\cdot}(X = i, Br, Cl) Radicals

    Science.gov (United States)

    Kline, Neal; Huang, Meng; Miller, Terry A.

    2016-06-01

    Cavity ringdown, near-infrared spectra have been previously observed following the photolysis of the dihalomethanes(CH{_2}XI, X = I, Br, Cl) in the presence of O{_2} and N{_2}. In last year's Symposium, we presented evidence that all the spectra could be attributed to the tilde{A}-tilde{X} electronic transition of the appropriate CH{_2}XOO{\\cdot} radical. We now present detailed analyses of these spectra. Similar spectral features have been observed for all radicals. The first strong transitions are located around 6800 cm{-1}, and are assigned as associated with the origin. Other strong transitions are observed about 800 cm{-1} blue of the origin, and have a multiple-peak structure similar to the corresponding origin bands. These bands are assigned to be the OO stretch of the tilde{A}-tilde{X} electronic transitions, which are typically strong in the spectra of peroxy radicals, based on electronic structure calculations that provide vibrational frequencies and Franck-Condon factors. One-dimensional calculations of the internal torsion mode are applied to specifically explain the multiple-peak features in both the origin and OO stretch region as series of transitions including sequence bands and other hot bands from the vibrationally excited states of the low-frequency torsion mode in the tilde{X} state, which are significantly populated at room temperature. Additional bands can be assigned to fundamentals or combination bands of various other tilde{A} state modes. N. D. Kline, M. Huang, T. A. Miller, P. Lolur, R. Dawes, FD05, 70th International Symposium of Molecular Spectroscopy(2015)

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

    Science.gov (United States)

    Barradas, N. P.; Bergmaier, A.; Mizohata, K.; Msimanga, M.; Räisänen, J.; Sajavaara, T.; Simon, A.

    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 Si3N4, 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 12C, 16O, 28Si, 35Cl, 58Ni, 79Br, and 127I 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.

  7. Coordination-directed one-dimensional coordination polymers generated from a new oxadiazole bridging ligand and HgX2 (X=Cl, Br and I).

    Science.gov (United States)

    Yang, Rui; Ma, Jian Ping; Huang, Ru Qi; Dong, Yu Bin

    2011-06-01

    A new 1,3,4-oxadiazole bridging bent organic ligand, 2,5-bis{5-methyl-2-[(4-pyridyl)methoxy]phenyl}-1,3,4-oxadiazole, C(28)H(24)N(4)O(3), L, has been used to create three novel one-dimensional isomorphic coordination polymers, viz. catena-poly[[[dichloridomercury(II)]-μ-2,5-bis{5-methyl-2-[(4-pyridyl)methoxy]phenyl}-1,3,4-oxadiazole] methanol monosolvate], {[HgCl(2)(C(28)H(24)N(4)O(3))]·CH(3)OH}(n), catena-poly[[[dibromidomercury(II)]-μ-2,5-bis{5-methyl-2-[(4-pyridyl)methoxy]phenyl}-1,3,4-oxadiazole] methanol monosolvate], {[HgBr(2)(C(28)H(24)N(4)O(3))]·CH(3)OH}(n), and catena-poly[[[diiodidomercury(II)]-μ-2,5-bis{5-methyl-2-[(4-pyridyl)methoxy]phenyl}-1,3,4-oxadiazole] methanol monosolvate], {[HgI(2)(C(28)H(24)N(4)O(3))]·CH(3)OH}(n). The free L ligand itself adopts a cis conformation, with the two terminal pyridine rings and the central oxadiazole ring almost coplanar [dihedral angles = 5.994 (7) and 9.560 (6)°]. In the Hg(II) complexes, however, one of the flexible pyridylmethyl arms of ligand L is markedly bent and helical chains are obtained. The Hg(II) atom lies in a distorted tetrahedral geometry defined by two pyridine N-atom donors from two L ligands and two halide ligands. The helical chains stack together via interchain π-π interactions that expand the dimensionality of the structure from one to two. The methanol solvent molecules link to the complex polymers through O-H···N and O-H···O hydrogen bonds. © 2011 International Union of Crystallography

  8. 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}).

  9. P-T PHASE DIAGRAM AND GOLD VALENCE STATE OF NEW GOLD MIXED-VALENCE COMPLEXES, Cs2[AuIX2][AuIIIY4](X, Y = Cl, Br, I; X ¹ Y

    Directory of Open Access Journals (Sweden)

    K. Ikeda

    2004-12-01

    Full Text Available Cs2[AuIX2][AuIIIX4](X = Cl, Br, and I is well known for the perovskite-type gold mixed-valence system. This system undergoes pressure-induced and photo-induced Au valence transition from the mixed valence state of AuI,III to the single valence state of AuII. Recently, we have succeeded in synthesizing new gold mixed-valence complexes having perovskite-type structure, Cs2[AuIX2][AuIIIY4](X, Y = halogen, X ¹ Y, in organic solvent by using a new method. This hetero-halogen bridged gold mixed-valence system was confirmed by means of Raman spectroscopy. From the analysis of 197Au Mössbauer spectra, it was elucidated that the charge transfer interaction between AuI(5dx2-y2 and AuIII(5dx2-y2in the a-b plane becomes dominant for the AuI-AuIII interaction in Cs2[AuIX2][AuIIIY4] (X, Y = Cl, Br, and I in the order of X = Cl < Br < I, where Y is fixed. In order to elucidate the Au valence transition for Cs2[AuIX2][AuIIIY4], we have investigated the X-ray diffraction and Raman spectra under high pressure. Moreover, we have synthesized TlAuX3(X = Cl and Br having cubic perovskite structure and highly conducting behavior. The Au valence state in TlAuX3 is considered to be AuII at ambient pressure.

  10. 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.

  11. QCD radiative corrections for $h\\to b\\bar b$ in the Standard Model Dimension-6 EFT

    CERN Document Server

    Gauld, Rhorry; Scott, Darren J

    2016-01-01

    We calculate the $\\mathcal{O}(\\alpha_s)$ QCD corrections to the inclusive $h\\to b\\bar b$ decay rate in the dimension-6 Standard Model Effective Field Theory (SMEFT). The QCD corrections multiplying the dimension-6 Wilson coefficients which alter the $hb\\bar b$-vertex at tree-level are proportional to the Standard Model (SM) ones, so next-to-leading order results can be obtained through a simple rescaling of the tree-level decay rate. On the other hand, contributions from the operators $Q_{bG}$ and $Q_{HG}$, which alter the $gb\\bar b$-vertex and introduce a $hgg$-vertex respectively, enter at $\\mathcal{O}(\\alpha_s)$ and induce sizeable corrections which are unrelated to the SM ones and cannot be anticipated through a renormalisation-group analysis. We present compact analytic results for these contributions, which we recommend to be included in future phenomenological studies.

  12. Computation of $H\\to gg$ in FDH and DRED: renormalization, operator mixing, and explicit two-loop results

    CERN Document Server

    Broggio, A; Signer, A; Stöckinger, D; Visconti, A

    2015-01-01

    The $H\\to gg$ amplitude relevant for Higgs production via gluon fusion is computed in the four-dimensional helicity scheme (FDH) and in dimensional reduction (DRED) at the two-loop level. The required renormalization is developed and described in detail, including the treatment of evanescent $\\epsilon$-scalar contributions. In FDH and DRED there are additional dimension-5 operators generating the $H g g$ vertices, where $g$ can either be a gluon or an $\\epsilon$-scalar. An appropriate operator basis is given and the operator mixing through renormalization is described. The results of the present paper provide building blocks for further computations, and they allow to complete the study of the infrared divergence structure of two-loop amplitudes in FDH and DRED.

  13. 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.

  14. Temperature calibration for high-temperature MAS NMR to 913 K: 63Cu MAS NMR of CuBr and CuI, and 23Na MAS NMR of NaNbO3.

    Science.gov (United States)

    Wu, Jingshi; Kim, Namjun; Stebbins, Jonathan F

    2011-09-01

    The solid-state phase transitions of CuBr, CuI and NaNbO(3) can be readily observed using (63)Cu and (23)Na high-temperature magic-angle spinning nuclear magnetic resonance spectroscopy. Temperature has large, linear effects on the peak maximum of (63)Cu in each solid phase of CuBr and CuI, and there is large jump in shift across each phase transition. The (23)Na MAS NMR peak intensities and the line widths in NaNbO(3) also clearly show its high-temperature transition to the cubic phase. These data can be used to calibrate high-temperature MAS NMR probes up to 913 K, which is two hundred degrees higher than the commonly-used temperature calibration based on the chemical shift of (207)Pb in Pb(NO(3))(2). Copyright © 2011 Elsevier Inc. All rights reserved.

  15. A Localized Molecular Orbital Study of the Halogen Substitution Effect on (103)Rh NMR Shielding in [Cp*RhX2]2, Where X = Cl, Br, or I.

    Science.gov (United States)

    Mirzaeva, Irina V; Mainichev, Dmitry A; Kozlova, Svetlana G

    2016-03-24

    (103)Rh NMR parameters and the bonding structure of three complexes of [Cp*RhX2]2, where X = Cl, Br, or I, have been studied with the help of natural bond orbitals (NBOs) and natural localized molecular orbitals (NLMOs). The complexes of [Cp*RhX2]2, where X = Cl, Br, or I, have similar bonding structures, with the major difference being in the degree of covalency of the Rh-X bonds. The decomposition of (103)Rh NMR shielding into diamagnetic, paramagnetic, and spin-orbit terms shows that normal halogen dependence (NHD) of the (103)Rh NMR shift is defined mostly by the paramagnetic term, with the spin-orbit term being significantly smaller. The decomposition of (103)Rh shielding into spin-free NBO and NLMO contributions shows that (103)Rh shielding is dominated by Rh d-orbital deshielding contributions. We explain the NHD of the (103)Rh NMR shift with the increase in the energies of the virtual antibonding Rh-X orbitals along the X = Cl, Br, and I series.

  16. 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.

  17. Bráður nýrnaskaði á Íslandi 1993-2011. Faraldsfræði, áhættuþættir og afdrif sjúklinga

    OpenAIRE

    Þórir Einarsson Long 1989

    2012-01-01

    Inngangur: Bráður nýrnaskaði (BNS) er algengt vandamál sem útheimtir oft kostnaðarsama erfiða meðferð og hefur háa dánartíðni. Tilgangur þessarar rannsóknar var að kanna faraldsfræði, áhættuþætti og afdrif sjúklinga sem fengu BNS á rannsóknartímabilinu. Efniviður og Aðferðir: Allar kreatínínmælingar sem gerðar hafa verið á Landspítalanum (LSH) frá maí 1993 til ársloka 2011 voru fengnar úr rafrænu kerfi LSH. Skrifað var forrit sem mat alla einstaklinga sem mældir höfðu verið með tilliti til...

  18. 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.

  19. 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.

  20. Hydrothermal syntheses and characterization of two novel luminescent Cadmium(II) frameworks: From 1D infinite triple Cd-(trz)-Cd bridges to a rare I2O0 network with 2D Cd-Br-Cd inorganic connectivity

    Science.gov (United States)

    Liu, Shi Xin; Li, Jian Hui; Wang, You You; Wu, Xiang Xia; Huo, Jian Zhong; Ding, Bin; Wang, Xiu Guang; Zhu, Zhao Zhou; Xia, Jun

    2015-05-01

    Using the 4-substituted-1,2,4-triazole derivate ligand 4-p-tolyl-1,2,4-triazole (L), two novel luminescent Cadmium(II) frameworks, namely {[Cd(μ2-L)3]·(NO3)2·L}n (1) and [Cd1.5(μ2-L)(μ2-Br)2(μ3-Br)]n (2) have been isolated under hydrothermal conditions. The structural analysis reveals that 1 presents a one-dimensional (1D) chain structural motif containing novel infinite triple Cd-(trz)-Cd bridges (triply trz-bridged M-M species). While 2 presents a rare I2O0 type framework, in which the infinite 2D Cd-Br-Cd inorganic connectivity with a 4-connected Kagome topology can be observed. The FT-IR, PXRD and thermal stabilities of 1-2 have investigated. The solid-state photo-luminescent spectra of organic ligand L and 1-2 also have been measured indicating strong emission bands.

  1. 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.

  2. Magnetic properties and phase transitions of iron boracites, Fe3B7O13 X (X = Cl, Br or I)

    OpenAIRE

    Andreica, Daniel Aurelian; Rivera, Jean-Pierre; Gentil, Sandrine; Ye, Zuo-Guang; Senthil kumar, M; Schmid, Hans

    1997-01-01

    Magnetic measurements for Fe-X (X = Cl, Br, and I) boracites at 3.6-300 K were performed. Temp. dependence of the magnetization and magnetic susceptibility for all compds. shows an antiferromagnetic order with Neel temps. of 11.5 K, 18.5 K, and 31 K, resp. The Curie-Weiss law holds for the temp. dependence of the magnetic susceptibility up to room temp. The effective magnetic moment obtained from the inverse susceptibility slope, for all compds., is higher than but close to the spin only valu...

  3. 2-Chlorovinyl tellurium dihalides, (p-tol)Te[C(H)=C(Cl)Ph]X{sub 2} for X = Cl, Br and I: variable coordination environments, supramolecular structures and docking studies in cathepsin B

    Energy Technology Data Exchange (ETDEWEB)

    Caracelli, Ignez, E-mail: ignez@ufscar.b [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Dept. de Fisica; Zukerman-Schpector, Julio; Maganhi, Stella H., E-mail: julio@power.ufscar.b [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Dept. de Quimica. Lab. de Cristalografia, Estereodinamica e Modelagem Molecular; Stefani, Helio A. [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Farmacia; Guadagnin, Rafael [Universidade Federal de Sao Paulo (Unifesp/EPM), Sao Paulo, SP (Brazil). Dept. de Quimica; Tiekink, Edward R.T., E-mail: edward.tiekink@gmail.co [University of Malaya, Kuala Lumpur (Malaysia). Dept. of Chemistry

    2010-07-01

    Crystallography shows that the Te atom in each of (p-tol)Te[C(H)=C(Cl)Ph]X{sub 2}, for X = Cl (1), Br (2) and I (3), is within a distorted {Psi}-pentagonal bipyramidal geometry. An E configuration for the vinyl group in (1) precludes the formation of an intramolecular Te...Cl interaction so that an intramolecular Te{pi} interaction is found instead. The coordination environment features a linear Cl-Te-Cl arrangement with the pentagonal plane defined by the two C atoms of the organic substituents, an intermolecular TeCl contact, a Te{pi} interaction and a stereochemically active lone pair of electrons. In the X = Br (2) and I (3) structures, similar coordination geometries are found but the Te{pi} contact is replaced by an intramolecular TeCl contact owing to the adoption of a Z configuration about the vinyl bond. The differences in structure are readily explained in terms of electronic effects. Docking studies of cathepsin B with (1')-(3'), i.e. 1-3 less one Te-bound halide, show efficient binding through the agency of covalent Te-S{sub Cys29} bonds with stabilization afforded by a combination of N-H{pi}, C-H{pi} and Cl{sub vinyl} H interactions. These results comparable favorably with known inhibitors of cathepsin B suggesting the title compounds have potential biological activity. (author)

  4. Halo- and azidodediazoniation of arenediazonium tetrafluoroborates with trimethylsilyl halides and trimethylsilyl azide and sandmeyer-type bromodediazoniation with Cu(I)Br in [BMIM][PF6] ionic liquid.

    Science.gov (United States)

    Hubbard, Abigail; Okazaki, Takao; Laali, Kenneth K

    2008-01-04

    Reaction of [ArN(2)][BF(4)] salts immobilized in [BMIM][PF(6)] ionic liquid (IL) with TMSX (X = I, Br) and TMSN(3) represents an efficient method for the preparation of iodo-, bromo-, and azido-derivatives via dediazoniation. The reactions can also be effected starting with ArNH(2) by in situ diazotization with [NO][BF(4)] followed by reaction with TMSX or TMSN(3). Depending on the substituents on the benzenediazonium cation, competing fluorodediazoniation (ArF formation) and hydrodediazoniation (ArH formation) were observed. Dediazoniation with TMSN(3) and with TMSI generally gave the highest chemoselectivity toward ArN(3) and ArI formation. The IL was recycled and reused up to 5 times with no appreciable decrease in the conversions. Multinuclear NMR monitoring of the interaction of [ArN(2)][BF(4)]/TMSX, [BMIM][PF6]/TMSX, and [BMIM][PF(6)]/TMSX/[ArN(2)][BF(4)] indicated that TMSF is formed primarily via [ArN(2)][BF(4)]/TMSX, generating [ArN(2)][X] in situ, which gives ArX on dediazoniation. Competing formation of ArF in Sandmeyer-type bromodediazoniation of [ArN(2)][BF(4)] with Cu(I)Br immobilized in the IL points to significant involvement of heterolytic dediazoniation.

  5. On the admissible range of the radial temperature gradient and Brünt-Väisäla frequency in the mantle and core: I. Main relations

    Science.gov (United States)

    Molodenskii, S. M.

    2017-03-01

    The question of ambiguity in the solution of the inverse problem for determining the Brünt-Väisäla frequency in the Earth's mantle from the entire set of the up-to-date data on seismicity, free oscillations, and forced nutations of the Earth, as well as the data on the Earth's total mass and total moment of inertia, is considered. Based on the results of a series of numerical experiments, the band of admissible distributions of the Brünt-Väisäla frequency and mantle density with depth is calculated. This estimate is used for investigating the convective and gravitational stability of the different regions of the mantle against relatively small adiabatic and nonadiabatic perturbations. The generalization of the known Rayleigh criterion of convective stability of homogeneous and a nonself-gravitating incompressible viscous fluid for the case of a compressible self-gravitating fluid is given. A system of the ordinary eight-order differential equations with complex coefficients and homogeneous boundary conditions, whose eigenvalues determine the transition from the stable state to instability, is obtained. Examples of the numerical determination of these eignevalues are presented. For interpreting the data about the band of the admissible distributions of the Brünt-Väisäla frequency with depth, the notion of the effective bulk modulus of the medium at different depths is introduced. This quantity governs the depth changes in temperature in a convecting mantle and allows us to make a conclusion about the role of heat conduction and the radial heterogeneity of the mantle composition without imposing any constraints on the convection mechanism. It is shown that within the present-day observation errors in the frequencies of the Earth's free oscillations, the simplest reasonable model is that in which the ratio of the effective bulk modulus to its adiabatic value in the lower and middle mantle is 1.043 ± 0.05. The closeness of this value to unity indicates that

  6. 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 = biological mechanisms or weathering of shale from glacial till.

  7. Electrocatalytic reduction of organohalides mediated by the dihalo-molybdenum phosphinic complexes trans-[MoX(2)(Ph(2)PCH(2)CH(2)PPh(2))(2)] (X = I, Br)-A mechanistic study by cyclic voltammetry digital simulation.

    Science.gov (United States)

    Martins, Natércia C T; Guedes da Silva, M Fátima C; Wanke, Riccardo; Pombeiro, Armando J L

    2009-06-28

    trans-[MoX(2)(dppe)(2)] (X = I, Br) act as inner-sphere electron-transfer mediators for the electrocatalytic reduction of organohalides RX to R + X(-), at both Mo(II)--> Mo(I) and Mo(I)--> Mo(0) reduction processes, each of them involving a cathodically induced heterolytic metal-halide bond cleavage with liberation of X(-) that is followed by addition of RX to the metal. Digital simulation of cyclic voltammetry at a wide range of scan rates allowed to estimate the rate constants of the various chemical steps for both electrocatalytic cycles, which were compared in terms of Mo-X bond dissociation energies, electronic and stereochemical effects.

  8. Synthesis, crystal structures and characterization of two novel organic-inorganic hybrid compounds (C5NH6)6Bi4Br18 and [C(NH2)3]3BiI6

    Science.gov (United States)

    Li, S. G.; Chen, L.; Xiang, Y.

    2017-02-01

    Two novel organic-inorganic compounds (C5NH6)6Bi4Br18 (1) and [C(NH2)3]3BiI6 (2) have been synthesized and characterized by elemental analysis, measured by DSC and single-crystal X-ray diffraction at room temperature. The crystal structure of (1) crystallizes in the monoclinic space group C2/m, with a = 17.12 (3), b = 15.3939 (1), c = 13.412 (2) Å, β = 123.702 (7)°, V = 3042.2 (8) Å3 and Z = 2. The crystal structure consists of discrete quad-core [Bi4Br18]6- anions and [C5NH6]+ cations. 2 crystallizes in triclinic space group P-1, with the following unit cell parameters: a = 9.3435 (2), b = 15.583 (4), c = 17.200 (4) Å, α = 86.383 (1), β = 75.689 (1), γ = 89.918 (6)°, V = 2421.5 (10) Å3 and Z = 4. The crystal lattice is composed of discrete [BiI6]3- anions surrounded by [C(NH2)3]+ cations. The DSC experiment of 1 clearly displays that a phase transition occurred at 124.7 K, while 2 undergoes a phase transition at 192.5 K.

  9. Energy and resolution calibration of NaI(Tl) and LaBr{sub 3}(Ce) scintillators and validation of an EGS5 Monte Carlo user code for efficiency calculations

    Energy Technology Data Exchange (ETDEWEB)

    Casanovas, R., E-mail: ramon.casanovas@urv.cat [Unitat de Fisica Medica, Facultat de Medicina i Ciencies de la Salut, Universitat Rovira i Virgili, ES-43201 Reus (Tarragona) (Spain); Morant, J.J. [Servei de Proteccio Radiologica, Facultat de Medicina i Ciencies de la Salut, Universitat Rovira i Virgili, ES-43201 Reus (Tarragona) (Spain); Salvado, M. [Unitat de Fisica Medica, Facultat de Medicina i Ciencies de la Salut, Universitat Rovira i Virgili, ES-43201 Reus (Tarragona) (Spain)

    2012-05-21

    The radiation detectors yield the optimal performance if they are accurately calibrated. This paper presents the energy, resolution and efficiency calibrations for two scintillation detectors, NaI(Tl) and LaBr{sub 3}(Ce). For the two former calibrations, several fitting functions were tested. To perform the efficiency calculations, a Monte Carlo user code for the EGS5 code system was developed with several important implementations. The correct performance of the simulations was validated by comparing the simulated spectra with the experimental spectra and reproducing a number of efficiency and activity calculations. - Highlights: Black-Right-Pointing-Pointer NaI(Tl) and LaBr{sub 3}(Ce) scintillation detectors are used for gamma-ray spectrometry. Black-Right-Pointing-Pointer Energy, resolution and efficiency calibrations are discussed for both detectors. Black-Right-Pointing-Pointer For the two former calibrations, several fitting functions are tested. Black-Right-Pointing-Pointer A Monte Carlo user code for EGS5 was developed for the efficiency calculations. Black-Right-Pointing-Pointer The code was validated reproducing some efficiency and activity calculations.

  10. Expanding Lone Pair···π Interactions to Nonaromatic Systems and Nitrogen Bases: Complexes of C2F3X (X = F, Cl, Br, I) and TMA-d9.

    Science.gov (United States)

    Geboes, Yannick; De Proft, Frank; Herrebout, Wouter A

    2015-06-04

    The molecular electrostatic potential surface of unsaturated, locally electron-deficient molecules shows a positive region perpendicular to (a part of) the molecular framework. In recent years it has been shown both theoretically and experimentally that molecules are able to form noncovalent interactions with Lewis bases through this π-hole. When studying unsaturated perfluorohalogenated molecules containing a higher halogen atom, a second electropositive region is also observed near the halogen atom. This region, often denoted as a σ-hole, allows the molecules to interact with Lewis bases and form a halogen bond. To experimentally characterize the competition between both these noncovalent interactions, Fourier transform infrared and Raman spectra of liquefied noble gas solutions containing perfluorohalogenated ethylene derivatives (C2F3X; X = F, Cl, Br, or I) and trimethylamine(-d9) were investigated. Analysis of the spectra shows that in mixed solutions of trimethylamine(-d9) and C2F4 or C2F3Cl lone pair···π complex is present, while evidence for halogen-bonded complex is found in solutions containing trimethylamine(-d9) and C2F3Cl, C2F3Br, or C2F3I. For all species observed, complexation enthalpies were determined, the values varying between -4.9(1) and -24.4 kJ mol(-1).

  11. Tracking different freshwater plumes at the Bay of Biscay scale by using a dissolved radioactive tracer: tritium (HTO)

    Science.gov (United States)

    Oms, Pierre-Emmanuel; Bailly du Bois, Pascal; Dumas, Franck; Lazure, Pascal; Morillon, Mehdi; Solier, Luc; Voiseux, Claire; Le Corre, Cédric; Maire, Donovan

    2017-04-01

    New measurements of a radioactive tracer (tritium) on the whole continental shelf of the Bay of Biscay during several oceanographic campaigns between 2008 and 2016 allow comparison with results of the plume dispersion from the regional circulation model, MARS3D (Lazure and Dumas, 2008). Seaward dispersion of freshwater in the Bay of Biscay is highly variable in time and depends on many processes like tide, wind, freshwater runoff or water mass stratification. Until now salinity was a useful tracer to describe dispersion of freshwater, but the complexity to account for these different sources require an additional conservative tracer. Tritium (3H) is a radionuclide tracer released as HTO in the Bay of Biscay by nuclear power plant through two French rivers, Loire and Gironde. Tritium inflow from Loire and Gironde are well known thanks to plants operator data and an effort of daily measurements. Indeed an automated and daily integrated sampling system is deployed in the Loire River and the Gironde Estuary. These plumes are clearly detectable over the continental shelf despite very low tritium concentrations (0.05 - 0.5 Bq/L, 0.5 - 5 TU). In order to determine such low tritium concentrations in the Bay of Biscay, we use a mass spectrometer to measure the 3He (gas) produced by radioactive disintegration of tritium after 3He ingrowth (1 - 6 months). The aim of this work is to describes and quantify the dispersion processes occurring in the continental shelf according to seasons. Thanks to assessments of the model dispersion compared to in-situ measurements, quantification of the residential time of freshwater in the continental shelf as well as quantification of their transfer from continental shelf to abyssal plain is possible. The 3H/S ratio will allow an estimation of respective inputs from Loire and Gironde in the bay.

  12. The VATO project: An original methodology to study the transfer of tritium as HT and HTO in grassland ecosystem.

    Science.gov (United States)

    Maro, D; Vermorel, F; Rozet, M; Aulagnier, C; Hébert, D; Le Dizès, S; Voiseux, C; Solier, L; Cossonnet, C; Godinot, C; Fiévet, B; Laguionie, P; Connan, O; Cazimajou, O; Morillon, M; Lamotte, M

    2017-02-01

    Tritium ((3)H) is mainly released into the environment by nuclear power plants, military nuclear facilities and nuclear reprocessing plants. The construction of new nuclear facilities in the world as well as the evolution of nuclear fuel management might lead to an increase of (3)H discharges from the nuclear industry. The VATO project was set up by IRSN (Institut de Radioprotection et de Sûreté Nucléaire) and EDF (Electricité de France) to reduce the uncertainties in the knowledge about transfers of (3)H from an atmospheric source (currently releasing HT and HTO) to a grassland ecosystem. A fully instrumented technical platform with specifically designed materials was set up downwind of the AREVA NC La Hague reprocessing plant (Northwest of the France). This study, started in 2013, was conducted in four main steps to provide an hourly data set of (3)H concentrations in the environment, adequate to develop and/or validate transfer models. It consisted first in characterizing the physico-chemical forms of (3)H present in the air around the plant. Then, (3)H transfer kinetics to grass were quantified regarding contributions from various compartments of the environment. For this purpose, an original experimental procedure was provided to take account for biases due to rehydration of freeze-dried samples for the determination of OBT activity concentrations in biological samples. In a third step, the (3)H concentrations measured in the air and in rainwater were reconstructed at hourly intervals. Finally, a data processing technique was used to determine the biological half-lives of OBT in grass. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Synthesis and characterization of the 1.1 adducts of copper(I) halides with bidentate N,N′-bis(benzophenone)-1,2-diiminoethane Schiff base: Crystal structures of [Cu(bz2en)2][CuX2] (X = Br, I) complexes

    NARCIS (Netherlands)

    Kia, Reza; Mirkhani, Valiollah; Harkema, Sybolt; Hummel, van Gerrit J.

    2007-01-01

    1:1 adducts of N,N′-bis(benzophenone)-1,2-diiminoethane (bz2en) with copper(I) chloride, bromide and iodide, [Cu(bz2en)2][CuX2] (X = Cl, Br, and I), have been synthesized and the structures of the solid bromide and iodide adducts were determined by X-ray crystallography from single-crystal data. The

  14. Three one-dimensional coordination polymers based on 1,1'-bis(pyridin-4-ylmethyl)-2,2'-bi-1H-benzimidazole and HgX2 (X = Cl, Br and I).

    Science.gov (United States)

    Li, Ai-Guo; Liu, Qi-Kui; Li, Yan-An; Liu, Zhi-Xian; Dong, Yu-Bin

    2014-01-01

    A new 2,2'-bi-1H-benzimidazole bridging organic ligand, namely 1,1'-bis(pyridin-4-ylmethyl)-2,2'-bi-1H-benzimidazole, C26H20N6, L or (I), has been synthesized and used to create three new one-dimensional coordination polymers, viz. catena-poly[[dichloridomercury(II)]-μ-1,1'-bis(pyridin-4-ylmethyl)-2,2'-bi-1H-benzimidazole], [HgCl2(C26H20N6)]n, (II), and the bromido, [HgBr2(C26H20N6)]n, (III), and iodido, [HgI2(C26H20N6)]n, (IV), analogues. Free ligand L crystallizes with two symmetry-independent half-molecules in the asymmetric unit and each L molecule resides on a crytallographic inversion centre. In structures (II)-(IV), the L ligand is also positioned on a crystallographic inversion centre, whereas the Hg centre resides on a crystallographic twofold axis. Compound (I) adopts an anti conformation in the solid state and forms a two-dimensional network in the crystallographic bc plane via π-π and C-H...π interactions. The three Hg(II) coordination complexes, (II)-(IV), have one-dimensional zigzag chains composed of L and HgX2 (X = Cl, Br and I), and the Hg(II) centres are in a distorted tetrahedral [HgX2N2] coordination geometry. Complexes (III) and (IV) are isomorphous, whereas complex (II) displays an interesting conformational difference from the others, i.e. a twist in the flexible bridging ligand.

  15. 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.

  16. Sensitivity of the decay $h\\to ZZ^*\\to Zl+l-$ to the Higgs self coupling through radiative corrections

    CERN Document Server

    Castilla-Valdez, H; Moyotl, A; Perez, M A

    2015-01-01

    We study the radiative corrections induced by the triple Higgs boson coupling $hhh$ in the three body decay $h\\to ZZ^*\\to Zl\\bar l$. We show that these corrections are potentially sensitive to the specific value of this coupling in the Standard Model and the Two Higgs Doublet Model. These effects may induce corrections to the integrated decay width of the three-body decay of order few percent and thus open a new window to test the Higgs boson self interaction.

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

    Energy Technology Data Exchange (ETDEWEB)

    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 {sup 2}2Na{sup +}-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{sub e}) and the rock-capacity factor ({alpha}). 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{sub d} values for HTO are in excellent agreement with values from batch sorption experiments and are of the order of 0.8. 10{sup -3} m{sup 3}/kg. Those for {sup 2}2Na{sup +} are of the order of 1.0. 10{sup -3} m{sup 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{sup -1}0 m{sup 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

  18. Facile fabrication of large-grain CH3NH3PbI3-xBrx films for high-efficiency solar cells via CH3NH3Br-selective Ostwald ripening

    Science.gov (United States)

    Yang, Mengjin; Zhang, Taiyang; Schulz, Philip; Li, Zhen; Li, Ge; Kim, Dong Hoe; Guo, Nanjie; Berry, Joseph J.; Zhu, Kai; Zhao, Yixin

    2016-08-01

    Organometallic halide perovskite solar cells (PSCs) have shown great promise as a low-cost, high-efficiency photovoltaic technology. Structural and electro-optical properties of the perovskite absorber layer are most critical to device operation characteristics. Here we present a facile fabrication of high-efficiency PSCs based on compact, large-grain, pinhole-free CH3NH3PbI3-xBrx (MAPbI3-xBrx) thin films with high reproducibility. A simple methylammonium bromide (MABr) treatment via spin-coating with a proper MABr concentration converts MAPbI3 thin films with different initial film qualities (for example, grain size and pinholes) to high-quality MAPbI3-xBrx thin films following an Ostwald ripening process, which is strongly affected by MABr concentration and is ineffective when replacing MABr with methylammonium iodide. A higher MABr concentration enhances I-Br anion exchange reaction, yielding poorer device performance. This MABr-selective Ostwald ripening process improves cell efficiency but also enhances device stability and thus represents a simple, promising strategy for further improving PSC performance with higher reproducibility and reliability.

  19. Kinetics and Spectroscopy of BrNO

    Science.gov (United States)

    1997-06-12

    v3 line positions 3-81 xii List of Tables Table Page 2.1. Experimental values of Keq, kf and kr ..................... 2-16 2.2. Data used to...BrNO," Journal of Applied Physics, 59:4184- 4186 (1986). 17. del Barrio, J. I. and F. M. G. Tablas . "Relative Intensities of the NO Vibro- Rotational

  20. Structural and electronic properties of α -(BEDT-TTF)2I3 , β -(BEDT-TTF)2I3 , and κ -(BEDT-TTF)2X3 (X = I, F, Br, Cl) organic charge transfer salts

    Science.gov (United States)

    Commeau, Benjamin; Geilhufe, R. Matthias; Fernando, Gayanath W.; Balatsky, Alexander V.

    2017-09-01

    (BEDT-TFF ) 2I3 charge transfer salts are reported to show superconductivity and pressure-induced quasi-two-dimensional Dirac cones at the Fermi level. By performing state of the art ab initio calculations in the framework of density functional theory, we investigate the structural and electronic properties of the three structural phases α , β , and κ . We furthermore report about the irreducible representations of the corresponding electronic band structures, symmetry of their crystal structure, and the origin of band crossings. Additionally, we discuss the chemically induced strain in κ -(BEDT-TTF ) 2I3 achieved by replacing the iodine layer with other halogens: fluorine, bromine, and chlorine. In the case of κ -(BEDT-TTF ) 2F3 , we identify topologically protected crossings within the band structure. These crossings are forced to occur due to the nonsymmorphic nature of the crystal. The calculated electronic structures presented here are added to the organic materials database (OMDB).

  1. Magnetic studies on hexahalorhenate(IV) salts of ferrocenium cations [Fe(C5R5)2]2[ReX6] (R = H, CH3; X = Cl, Br, I).

    Science.gov (United States)

    González, Ricardo; Chiozzone, Raúl; Kremer, Carlos; Guerra, Francesca; De Munno, Giovanni; Lloret, Francesc; Julve, Miguel; Faus, Juan

    2004-05-01

    The hexahalorhenate(IV) salts of formula [Fe(C5H5)2]2[ReX6], with X = Cl (1), Br (2), and I (3), and [Fe(C5Me5)2]2[ReX6], with X = Cl (4), Br (5), and I (6) ([Fe(C5Me5)2]+ = decamethylferrocenium cation), have been synthesized and the structures of 1, 2, and 4 determined by single-crystal X-ray diffraction. 1, 2, and 4 crystallize in the orthorhombic system, space groups Pbca (1 and 2) and Ibam (4), with a = 14.099(2) A, b = 16.125(2) A, and c = 22.133(15) A, for 1, a = 14.317(3) A, b = 16.848(3) A, and c = 22.099(2) A for 2, and a = 15.8583(5) A, b = 15.9368(5) A, and c = 16.9816(6) A for 4. The three structures are made up of discrete [ReX6]2- anions and ferrocenium cations held together by electrostatic forces. There are anion-anion contacts in 1 and 2 but only through one direction. The [ReX6]2- octahedra are arranged along the y axis forming chains of Re and X atoms, -Re-X...X-Re-X...X-Re-, where the intermolecular X...X distances are shorter than the van der Waals distances. A somewhat greater separation between the anions occurs in 4. The magnetic properties of 1-6 were investigated in the temperature range 2.0-300 K. 1, 2, 4, and 5 exhibit an antiferromagnetic coupling between the anions, whereas a ferromagnetic coupling between anions and cations is the dominant interaction in 3. 6 behaves as a magnetically isolated compound, its susceptibility being the simple addition of the independent contributions of the uncoupled paramagnetic cations and anions.

  2. Skadelige brændeovne

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf; Czeskleba-Dupont, Solveig

    2006-01-01

    Sektorforskningen har siden 2001 påvist alarmerende toskiske emissioner fra brændeovne såsom PAH og dioxin, der ikke følges ad i dannelsen og derfor heller ikke kan bekæmpes målrettet. Reguleringsmyndigheden unddrager sig imidlertid forpligtigelsen fra bl.a. Stockholmkonventionen angående POPs om...... at nedbringe den slags forurening mest muligt under henvisning til dogmet om al biomasses CO2-neutralitet, hvilket tilbagevises. Både fysikeren Bent Sørensen/RUC og 2001 rapporten fra IPCC har påpeget at dette ikke (mere) slår til ved planter med årtiers omdriftstid....

  3. High temporal resolution Br2, BrCl and BrO observations in coastal Antarctica

    Directory of Open Access Journals (Sweden)

    R. von Glasow

    2013-02-01

    Full Text Available There are few observations of speciated inorganic bromine in polar regions against which to test current theory. Here we report the first high temporal resolution measurements of Br2, BrCl and BrO in coastal Antarctica, made at Halley during spring 2007 using a Chemical Ionisation Mass Spectrometer (CIMS. We find indications for an artefact in daytime BrCl measurements arising from conversion of HOBr, similar to that already identified for observations of Br2 made using a similar CIMS method. Using the MISTRA model, we estimate that the artefact represents a conversion of HOBr to Br2 of the order of several tens of percent, while that for HOBr to BrCl is less but non-negligible. If the artefact is indeed due to HOBr conversion, then nighttime observations were unaffected. It also appears that all daytime BrO observations were artefact-free. Mixing ratios of BrO, Br2 and BrCl ranged from instrumental detection limits to 13 pptv (daytime, 45 pptv (nighttime, and 6 pptv (nighttime, respectively. We see considerable variability in the Br2 and BrCl observations over the measurement period which is strongly linked to the prevailing meteorology, and thus air mass origin. Higher mixing ratios of these species were generally observed when air had passed over the sea-ice zone prior to arrival at Halley, than from over the continent. Variation in the diurnal structure of BrO is linked to previous model work where differences in the photolysis spectra of Br2 and O3 is suggested to lead to a BrO maximum at sunrise and sunset, rather than a noon-time maxima. This suite of Antarctic data provides the first analogue to similar measurements made in the Arctic, and of note is that our maximum measured BrCl (nighttime is less than half of the maximum measured during a similar period (spring-time in the Arctic (also nighttime. This difference in maximum measured BrCl may also be the cause of a difference in the Br2 : BrCl ratio between the Arctic and Antarctic. An

  4. Impact of a four-zero Yukawa texture on $h\\to \\gamma \\gamma$ and $\\gamma Z$ in the framework of the 2-Higgs Doublet Model Type III

    CERN Document Server

    Cordero-Cid, A; Honorato, C G; Moretti, S; Perez, M A; Rosado, A

    2013-01-01

    We study the substantial enhancement, with respect to the corresponding Standard Model rates, that can be obtained for the branching ratios of the decay channels $h \\to \\gamma \\gamma$ and $h\\to \\gamma Z$ within the framework of the 2-Higgs-Doublet Model Type III, assuming a four-zero Yukawa texture and a general Higgs potential. We show that these processes are very sensitive to the flavour pattern entering the Yukawa texture and to the triple coupling structure of the Higgs potential, both of which impact onto the aforementioned decays. We can accommodate the parameters of the model in such a way to obtain the $h \\to \\gamma \\gamma$ rates reported by the Large Hadron Collider and at the same time get a $h\\to \\gamma Z$ fraction much larger than in the Standard Model, indeed within experimental reach. We present some scenarios where this phenomenology is realised for spectrum configurations that are consistent with current constraints. We also discuss the possibility of obtaining a light charged Higgs boson com...

  5. Ligand dependence of metal-metal bonding in the d(3)d(3) dimers M(2)X(9)(n-) (M(III) = Cr, Mo, W; M(IV) = Mn, Tc, Re; X = F, Cl, Br, I).

    Science.gov (United States)

    Stranger, R; Turner, A; Delfs, C D

    2001-08-13

    The ligand dependence of metal-metal bonding in the d(3)d(3) face-shared M(2)X(9)(n-) (M(III) = Cr, Mo, W; M(IV) = Mn, Tc, Re; X = F, Cl, Br, I) dimers has been investigated using density functional theory. In general, significant differences in metal-metal bonding are observed between the fluoride and chloride complexes involving the same metal ion, whereas less dramatic changes occur between the bromide and iodide complexes and minimal differences between the chloride and bromide complexes. For M = Mo, Tc, and Re, change in the halide from F to I results in weaker metal-metal bonding corresponding to a shift from either the triple metal-metal bonded to single bonded case or from the latter to a nonbonded structure. A fragment analysis performed on M(2)X(9)(3-) (M = Mo, W) allowed determination of the metal-metal and metal-bridge contributions to the total bonding energy in the dimer. As the halide changes from F to I, there is a systematic reduction in the total interaction energy of the fragments which can be traced to a progressive destabilization of the metal-bridge interaction because of weaker M-X(bridge) bonding as fluoride is replaced by its heavier congeners. In contrast, the metal-metal interaction remains essentially constant with change in the halide.

  6. Synthesis, Crystal Structure and Thermal Stability Study of [Cu2(bpe)X2]n (bpe=1,2-trans-bi(4-pyridyl)ethene, X=Cl, Br, I)

    Institute of Scientific and Technical Information of China (English)

    CHEN San-Ping; FAN Guang; GAO Sheng-Li

    2008-01-01

    A series of copper(Ⅰ) halide complexes bridged by bpe (bpe=1,2-trans-bi(4-pyridyl)ethene), [Cu2(bpe)Cl2]n (1),[Cu2(bpe)Br2]n (2) and [Cu2(bpe)I2]n (3) were successfully synthesized and complex 1 has been structurally characterizod by a single crystal X-ray diffraction method.Crystal data for 1 are monoclinic, space group P2(1)/c, a=0.3788(8) nm, b=1.5059(3) nm, c=1.0875(2) nm, β=96.262(4)°, V=0.6165(2) nm3, Z=2, S=1.002, final R indices [I>2σ(I)] R1=0.0288, wR2=0.0579, R index (all data) R1=0.0509, wR2=0.0615.Elemental analyses and IR spectra reveal that the complexes are of isomorphic compounds.In addition, thermogravimetric analyses were also applied to research of the thermal stability of the title complexes.

  7. 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

  8. 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

  9. 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.

  10. The structure of PX{sub 3} (X = Cl, Br, I) molecular liquids from X-ray diffraction, molecular dynamics simulations, and reverse Monte Carlo modeling

    Energy Technology Data Exchange (ETDEWEB)

    Pothoczki, Szilvia, E-mail: pothoczki.szilvia@wigner.mta.hu; Temleitner, László; Pusztai, László [Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Konkoly-Thege M. út 29-33, 1121 Budapest (Hungary)

    2014-02-07

    Synchrotron X-ray diffraction measurements have been conducted on liquid phosphorus trichloride, tribromide, and triiodide. Molecular Dynamics simulations for these molecular liquids were performed with a dual purpose: (1) to establish whether existing intermolecular potential functions can provide a picture that is consistent with diffraction data and (2) to generate reliable starting configurations for subsequent Reverse Monte Carlo modelling. Structural models (i.e., sets of coordinates of thousands of atoms) that were fully consistent with experimental diffraction information, within errors, have been prepared by means of the Reverse Monte Carlo method. Comparison with reference systems, generated by hard sphere-like Monte Carlo simulations, was also carried out to demonstrate the extent to which simple space filling effects determine the structure of the liquids (and thus, also estimating the information content of measured data). Total scattering structure factors, partial radial distribution functions and orientational correlations as a function of distances between the molecular centres have been calculated from the models. In general, more or less antiparallel arrangements of the primary molecular axes that are found to be the most favourable orientation of two neighbouring molecules. In liquid PBr{sub 3} electrostatic interactions seem to play a more important role in determining intermolecular correlations than in the other two liquids; molecular arrangements in both PCl{sub 3} and PI{sub 3} are largely driven by steric effects.

  11. Expanding the Chemistry of Actinide Metallocene Bromides. Synthesis, Properties and Molecular Structures of the Tetravalent and Trivalent Uranium Bromide Complexes: (C5Me4R2UBr2, (C5Me4R2U(O-2,6-iPr2C6H3(Br, and [K(THF][(C5Me4R2UBr2] (R = Me, Et

    Directory of Open Access Journals (Sweden)

    Alejandro G. Lichtscheidl

    2016-01-01

    Full Text Available The organometallic uranium species (C5Me4R2UBr2 (R = Me, Et were obtained by treating their chloride analogues (C5Me4R2UCl2 (R = Me, Et with Me3SiBr. Treatment of (C5Me4R2UCl2 and (C5Me4R2UBr2 (R = Me, Et with K(O-2,6-iPr2C6H3 afforded the halide aryloxide mixed-ligand complexes (C5Me4R2U(O-2,6-iPr2C6H3(X (R = Me, Et; X = Cl, Br. Complexes (C5Me4R2U(O-2,6-iPr2C6H3(Br (R = Me, Et can also be synthesized by treating (C5Me4R2U(O-2,6-iPr2C6H3(Cl (R = Me, Et with Me3SiBr, respectively. Reduction of (C5Me4R2UCl2 and (C5Me4R2UBr2 (R = Me, Et with KC8 led to isolation of uranium(III “ate” species [K(THF][(C5Me52UX2] (X = Cl, Br and [K(THF0.5][(C5Me4Et2UX2] (X = Cl, Br, which can be converted to the neutral complexes (C5Me4R2U[N(SiMe32] (R = Me, Et. Analyses by nuclear magnetic resonance spectroscopy, X-ray crystallography, and elemental analysis are also presented.

  12. <i>Euphorbia candelabrumi> auctt

    Directory of Open Access Journals (Sweden)

    Leach, L. C.

    1992-12-01

    Full Text Available The paper discusses the taxonomic data of <i>Euphorbia candelabrumi> Welwitseh and the illegitimate <i>E. candelabrumi> Kotschy.<br>>En aquest treball es discuteix informació taxonòmica sobre <i>Euphorbia candelabrumi> Welwitsch i el nom il-legitim <i>E. candelabrumi> Kotschy.

  13. A BDT optimization study and assessment of deep learning in selecting VBF events in the $H\\to ZZ^{*}\\to4l$ channel

    CERN Document Server

    Morningstar, Alan

    2015-01-01

    Since the discovery of the Higgs boson in 2012, the most recently confirmed and final piece of the Standard Model has been rigorously studied in various production modes and decay channels. However, Run 1 of the LHC did not yield sufficient statistics to resolve production modes in the $H\\to ZZ^{*}\\to4l$ channel. Current and future runs of the LHC will offer sufficient data to do so, thus machine learning techniques used to separate the two most frequent Higgs boson production modes - gluon fusion and vector boson fusion - were studied and the findings are presented in this report. An optimization of boosted decision trees trained on $\\sqrt{s}=\\text{8 TeV}$ ATLAS Monte Carlo data is presented. The feasibility of improving classification efficiency by using deep neural networks is also studied and detailed below.

  14. Low energy electrons scattering by C F{sub 4}, C Cl{sub 4}, Si Cl{sub 4}, Si Br{sub 4} and Si I{sub 4}; Espalhamento de eletrons de baixa energia por C F{sub 4}, C Cl{sub 4}, Si Cl{sub 4}, Si Br{sub 4} e Si I{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Policastro, Alexandra Pardo

    1994-12-31

    Cross section calculations of low energy e{sup -} -molecule scattering have been limited to targets with few electrons. We show that the use of soft norm-conserving pseudopotentials in the target description and in the scattering calculations makes possible the study of the low-energy electron scattering by many-electron molecules. We present results for C F{sub 4}, C Cl{sub 4}, Si Cl{sub 4}, Si Br{sub 4} and Si L{sub 4} with 42, 74, 82, 154, and 226 electrons respectively. The pseudopotentials replace the nucleus and the core electrons of each atom so that only the valence is described in a many-body framework. Our calculated cross sections are in good qualitative agreement wit experiment. Except for C F{sub 4}, we show theoretical cross sections for these molecules for the first time. For the C F{sub 4} molecule our results are in excellent agreement with the theoretical data available in the literature [8], which is an all-electron calculation, and also with the experimental results [11]. (author) 17 refs., 11 figs., 4 tabs.

  15. 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.

  16. 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

  17. A general synthetic route to [Cu(X)(NHC)] (NHC = N-heterocyclic carbene, X = Cl, Br, I) complexes† †Electronic supplementary information (ESI) available: Optimisation details and full characterisation data. CCDC 940850–940853. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c3cc45488f Click here for additional data file.

    Science.gov (United States)

    Santoro, Orlando; Collado, Alba; Slawin, Alexandra M. Z.; Nolan, Steven P.

    2013-01-01

    A one-pot procedure for the synthesis of [Cu(X)(NHC)] (X = Cl, Br, I) is reported. The reaction is applicable to a wide range of saturated and unsaturated NHC ligands, is scalable and proceeds under mild conditions using technical grade solvents in air. PMID:24087835

  18. 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

  19. Phase Diagram of the System KCI-CsBr-CaBr2%KCI-CsBr-CaBr2相图的研究

    Institute of Scientific and Technical Information of China (English)

    包新华; 陈华莉; 陆文聪; 阎立诚

    2001-01-01

    A computer prediction for the regularities of formation of binary bromide system was made. The results indicate that CsBr-CaBr2 molten salt system is binary complex compound-forming system. The phase diagram of CsBr-CaBr2 system has been determined by visual polythermal method in order to prove the prediction. The phase diagrams of the quasibinary system KCl-CsBr, KC1-CaBr2 and the quasiternary system CsBr-CaBr2-KC1 were determined by using visual polythermal method. The phase diagrams of CsBr-CaBr2 and KCl-CaBr2 show that the intermediate compound is formed. The results are in agreement with the computer prediction. Here, the various parts of the phase diagram of the quasiternary system CsBr-CaBr2-KCl were discussed.

  20. Phase Diagram of the System KCI-CsBr-CaBr2%KCI-CsBr-CaBr2相图的研究

    Institute of Scientific and Technical Information of China (English)

    包新华; 陈华莉; 陆文聪; 阎立诚

    2000-01-01

    A computer prediction for the regularities of formation of binary bromide system was made. The results indicate that CsBr-CaBr2 molten salt system is binary complex compound-forming system. The phase diagram of CsBr-CaBr2 system has been determined by visual polythermal method in order to prove the prediction. The phase diagrams of the quasibinary system KCl-CsBr, KC1-CaBr2 and the quasiternary system CsBr-CaBr2-KC1 were determined by using visual polythermal method. The phase diagrams of CsBr-CaBr2 and KCl-CaBr2 show that the intermediate compound is formed. The results are in agreement with the computer prediction. Here, the various parts of the phase diagram of the quasiternary system CsBr-CaBr2-KCl were discussed.

  1. Phosphorescence and zero-field optically detected magnetic resonance studies of (nd){sup 10} transition-metal complexes. 1. ZnX{sub 2}(phen) (X = Cl, Br, I)

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Shigeru; Yamamoto, Seiichi; Azumi, Tohru [Tohoku Univ., Sendai (Japan)] [and others

    1992-08-06

    In order to elucidate the effect of (nd){sup 10} central metal ions on the properties of the low-lying excited states of metal complexes, spectroscopic and optically detected magnetic resonance studies on the phenanthroline (phen) localized {sup 3}{pi}{pi}* states of ZnX{sub 2}(phen) (X = Cl, Br, I) were carried out. Comparison of the properties of the spin sublevels of ZnX{sub 2}(phen) with those of the uncoordinated 1, 10-phenanthroline yielded several noteworthy features: (a) the phosphorescence spectra of ZnX{sub 2}(phen) complexes very closely resemble that of the uncoordinated phen molecule, (b) the magnitudes of the zero-field splittings follow the ordering phen > ZnCl{sub 2}(phen) replacing the z sublevel (in-plane component) as the dominant decay channel in uncoordinated phen. These experimental results have been interpreted systematically and satisfactorily by a model invoking Heitler-London type mixing of LLCT (halogen p-orbitals to phen charge transfer) electronic configurations with the phen locally excited electronic configuration. 31 refs., 4 figs., 7 tabs.

  2. The structure of C5H 5RFe (+) (R = F, Cl, Br, I, O, OH, OCH3, C 6H 5, H) ions in the gas phase and the generation of their neutral counterparts by neutralization-reionization mass spectrometry.

    Science.gov (United States)

    Zagorevskii, D V; Holmes, J L; Zverev, D V; Orlova, T Y; Nekrasov, Y S

    1995-12-01

    The structure of C5H5FeR(+·) ions was studied by tandem mass spectromerry that included the neutralization-reionization (NR) method. Halogen-containing species (R = F, Cl, Br, I) showed fragmentation that was consistent with a structure that has the cyclopentadienyl ring and R as separate ligands at the metal atom (structure A). This structure also was identified for C5H5FeO(+) and CpFeOH(+·) ions, but these species also easily isomerized to metal-cyclopentadiene structure, RC5H5Fe(+·) (B), followed by hydrogen rearrangement(s) and CO loss. B was the dominant structure of C5H5FeH(+·) and C5H5FeC6H 5 (+·) ions. All ions that have structure A showed recovery signals in their NR mass spectra that indicated that their stable neutral counterparts were generated. The NR mass spectra also provided complementary information about the structure of ions before neutralization and after reionization.

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

    Science.gov (United States)

    Demissie, Taye B; Jaszuński, Michał; Komorovsky, Stanislav; Repisky, Michal; Ruud, Kenneth

    2015-10-28

    We present nuclear spin-rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants, and shielding spans of all the nuclei in (175)LuX and (197)AuX (X = (19)F, (35)Cl, (79)Br, (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.

  4. 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.

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

    Science.gov (United States)

    Demissie, Taye B.; Jaszuński, Michał; Komorovsky, Stanislav; Repisky, Michal; Ruud, Kenneth

    2015-10-01

    We present nuclear spin-rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants, and shielding spans of all the nuclei in 175LuX and 197AuX (X = 19F, 35Cl, 79Br, 127I), 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.

  6. Decay times of the spin-forbidden and spin-enabled transitions of Yb(2+) doped in CsCaX3 and CsSrX3 (X = Cl, Br, I).

    Science.gov (United States)

    Suta, Markus; Senden, Tim; Olchowka, Jacob; Adlung, Matthias; Meijerink, Andries; Wickleder, Claudia

    2017-03-08

    In this paper, a systematic study of the decay times of the spin-enabled and spin-forbidden transitions of Yb(2+) doped into the halidoperovskites CsMX3 (M = Ca, Sr; X = Cl, Br, I) is presented. The spin-forbidden transitions are characterized by ms decay times, which are typical for Yb(2+). On the contrary, the spin-enabled transitions show much shorter decay times in the range of μs and have so far only been rarely observed. These results allow detailed conclusions about systematics of the decay times of Yb(2+) doped in similar compounds and their correlation to the local structure of the coordination sphere of Yb(2+) as well as the role of vibrational interaction between the excited high spin (HS) and low spin (LS) states. The halidoperovskites are ideally suited as host lattices in this context and may work as text book examples due to their comparable structures, which allows a detailed interpretation of the decay times in relation to the local structure. An understanding of the impact of the composition and structure of the host material on the decay times of Yb(2+) will be of relevance for future applications of this activator in scintillators or lighting materials.

  7. Spectroscopic ellipsometry thin film and first-principles calculations of electronic and linear optical properties of [(C9H19NH3)2PbI2Br2] 2D perovskite

    Science.gov (United States)

    Abid, H.; Hlil, E. K.; Abid, Y.

    2017-03-01

    In this study we report results of first-principles density functional calculations using the full-potential linearized augmented plane wave (FP-LAPW) method as implemented in the WIEN2K code. We employed the generalized gradient approximation (GGA) for the exchange-correlation energy to calculate electronic and linear optical properties of the (C9H19NH3)2PbI2Br2 compound. The linear optical properties, namely, the real ε1 (ω) and imaginary ε2 (ω) parts of dielectric function, the refractive index n (ω) and the extinction coefficient k (ω) are calculated and compared with experimental spectroscopic ellipsometry spectra. The reflectivity R (ω) and electron energy loss function L (ω) are calculated too. Our calculations performed for band structure and density of states show that the valence band maximum and conduction band minimum are located at Γ point resulting in a direct band gap of about (Γv -Γc) of 2.42 eV in good agreement with the experimental data. The investigated compound has a large uniaxial anisotropy of the dielectric function of about 0.0739 and a negative birefringence at zero energy Δn (0) =-0.11.

  8. Core-shell Cd0.2Zn0.8S@BiOX (X = Cl, Br and I) microspheres: a family of hetero-structured catalysts with adjustable bandgaps, enhanced stability and photocatalytic performance under visible light irradiation.

    Science.gov (United States)

    Zhou, Yannan; Wen, Ting; Chang, Binbin; Yang, Baocheng; Wang, Yonggang

    2016-09-21

    Heterostructures consisting of two semiconductors have merited considerable attention in photocatalytic applications due to synergistic effects in complex redox processes. The incorporation of solid solutions into such architectures can further offer extra variability to control the bandgap. In this study, we report the fabrication of a series of core-shell Cd0.2Zn0.8S@BiOX (X = Cl, Br and I) microspheres via a solvothermal route that lead to enhanced photocatalytic performance under visible light irradiation. By optimizing the synthesis conditions, uniform and porous Cd0.2Zn0.8S@BiOX microspheres were achieved. The products were thoroughly characterized by X-ray diffraction studies, scanning electron microscopy, transmission electron microscopy, photoluminescence studies, absorption measurements and the photodegradation of RhB. Remarkably, the electronic structures of Cd0.2Zn0.8S@BiOX composites can be continuously tuned by varying the composition of BiOX to achieve the best catalytic performance under visible light irradiation. Finally, this greatly enhanced visible-light-driven photocatalytic efficiency was observed in the optimized Cd0.2Zn0.8S@BiOI composites when compared to their single-component counterparts, which may be attributed to increased light absorption and improved electron-hole separation. The photocatalytic mechanism has also been proposed based on the experimental evidences and the theoretical band positions of Cd0.2Zn0.8S@BiOI.

  9. Theoretical study on the identity ion pair SN2 reactions of LiX with CH3SX (X=Cl, Br, and I): structure, mechanism, and potential energy surface.

    Science.gov (United States)

    Ren, Yi; Gai, Jing-Gang; Xiong, Yan; Lee, Kuo-Hsing; Chu, San-Yan

    2007-07-26

    Three archetypal ion pair nucleophilic substitution reactions at the methylsulfenyl sulfur atom LiX+CH3SX-->XSCH3+LiX (X=Cl, Br, and I) are investigated by the modified Gaussian-2 theory. Including lithium cation in the anionic models makes the ion pair reactions proceed along an SN2 mechanism, contrary to the addition-elimination pathway occurring in the corresponding anionic nucleophilic substitution reactions X-+CH3SX-->XSCH3+X-. Two reaction pathways for the ion pair SN2 reactions at sulfur, inversion and retention, are proposed. Results indicate the inversion pathway is favorable for all the halogens. Comparison of the transition structures and energetics for the ion pair SN2 at sulfur with the potential competition ion pair SN2 reactions at carbon LiX+CH3SX-->XCH3+LiXS shows that the SN2 reactions at carbon are not favorable from the viewpoints of kinetics and thermodynamics.

  10. Novel CX⋯π halogen bonds in complexes of acetylene and its derivatives of Na and MPH3 (M=Cu, Ag, Au) with XCCF (X=Cl, Br, I).

    Science.gov (United States)

    Zhuo, Hongying; Liu, Mingjuan; Li, Qingzhong; Li, Wenzuo; Cheng, Jianbo

    2014-06-05

    Ab initio calculations have been carried out for a variety of model systems with a T-shaped CX⋯π motif. The CX⋯π interaction of acetylene with the halogen donor molecule XCCF (X=Cl, Br, I) is invariably found to be weak with the interaction energy less than 11kJ/mol in magnitude. Substitution of the two protons in acetylene with more electron-donating sodium atoms increases the π electron density in the CC bond and leads to a substantial enhancement in its interaction with the halogen donor. The calculated interaction energies increase to as much as 73kJ/mol in the case of C2Na2-ICCF. The interaction of XCCF with a model coinage metal ethynide, H3PMCCMPH3 (M=Cu, Ag, Au), is intermediate between these two extremes, and the interaction energy is related to the nature of coinage metals. The CX⋯π halogen bonds have been analyzed with natural bond orbital, atoms in molecules, and energy decomposition.

  11. 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

  12. 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.

  13. Recent Advances in the High Performance BiOX(X=Cl, Br, I) Based Photo-catalysts%基于BiOX(X=Cl、Br、I)新型高性能光催化材料的最新研究进展

    Institute of Scientific and Technical Information of China (English)

    刘家琴; 吴玉程

    2015-01-01

    Bismuth-based semiconductor of BiOX(X=Cl, Br, I) has proved to be a new promising photocatalytic material due to its unique layered crystal structure and suitable band gaps, which exhibits superior photocatalytic performance and high stability. In this review, some key scientific topics in terms of photocatalysis of BiOX(X=Cl, Br, I) were firstly addressed, then the effective modification methods were comprehensively sum-marized, including microstructure adjustment, heterojunction construction, noble-metal deposition, doping, sur-face sensitization, etc. In addition, the research progress in catalyst immobilization by loading nano-structured BiOX(X=Cl, Br, I) onto appropriate carriers were also reviewed. Generally, this review presents the most recent advances of high performance of the BiOX(X=Cl, Br, I) based photocatalysts in depth and also prospects the re-search trend of the BiOX(X=Cl, Br, I) catalyst.%铋系半导体 BiOX(X=Cl、Br、I)因其独特的层状结构和合适的禁带宽度而表现出优异的光催化活性与稳定性,已成为光催化材料领域极具应用前景的材料体系。本文首先针对BiOX(X=Cl、Br、I)光催化材料研究中的关键科学问题进行了深入分析,进一步综述了国内外解决上述关键问题所采取的有效措施,包括:微结构调控、半导体复合、贵金属沉积、离子掺杂和表面敏化等,并针对纳米结构BiOX(X=Cl、Br、I)负载于合适载体上实现固载的研究进展进行了概述,从而对基于BiOX(X=Cl、Br、I)新型高性能光催化材料的最新研究进展进行了全面深入的综述,最后展望了BiOX光催化材料的研究方向与趋势。

  14. Application of the matrix element method in the search for ttH, $H\\to b\\overline{b}$ in the lepton+jets channel, using the ATLAS detector

    CERN Document Server

    Connelly, Ian; The ATLAS collaboration

    2015-01-01

    A talk summarising the use of the matrix element method in the lepton+jets ttH ($H\\to b\\bar{b}$) search channel with the 8 TeV dataset collected by ATLAS. A brief outline of the analysis strategy is presented followed by some details on the calculation of the matrix element method in creating a discriminating variable designed to separate two classes of events.

  15. The role of Li+ ions in the gas phase dehydrohalogenation and dehydration reactions of i-C3H7Br and i-C3H7OH molecules studied by radiofrequency-guided ion beam techniques and ab initio methods

    Science.gov (United States)

    López, E.; Lucas, J. M.; de Andrés, J.; Albertí, M.; Bofill, J. M.; Aguilar, A.

    2017-04-01

    Gas phase reactive collisions between lithium ions and i-C3H7X (X = Br, OH) molecules have been studied under single collision conditions in the center of mass (CM) 0.01-10.00 eV energy range using a radiofrequency-guided ion beam apparatus. Mass spectrometry analysis of the products did show the presence of [C3H6—Li]+, [HX—Li]+, C3H7+, and C2H3+ as well as of the [Li—i-C3H7Br]+ adduct while [Li—i-C3H7OH]+ was hardly detected. For all these reactive processes, the corresponding cross sections have been measured in absolute units as a function of the CM collision energy. Quantum chemistry ab initio calculations done at the second order Möller Plesset level have provided relevant information on the topology of the potential energy surfaces (PESs) where a reaction takes place allowing the characterization of the stationary points on the respective PESs along their reaction pathways. The connectivity of the different stationary points localized on the PESs was ensured by using the intrinsic reaction coordinate (IRC) method, confirming the adiabatic character of the reactions. The main topology features of the reactive PESs, in the absence of dynamical calculations, were used to interpret at the qualitative level the behavior of the experimental excitations functions, evidencing the role played by the potential energy barriers on the experimental dynamics of the reactions. Reaction rate constants at 303.2 K for different reactions have been calculated from measured excitation functions.

  16. 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+).

  17. The synthesis and crystal structures of halogenated tolans p-X-C6H4-C[triple bond]C-C6F5 and p-X-C6F4-C[triple bond]C-C6H5(X=F, Cl, Br, I).

    Science.gov (United States)

    Collings, Jonathan C; Burke, Jacquelyn M; Smith, Philip S; Batsanov, Andrei S; Howard, Judith A K; Marder, Todd B

    2004-11-07

    A series of halogenated, partially fluorinated tolans of general formula p-X-C6H4-C[triple bond]C-C6F5[X=I (1), Br (2), Cl (3), F (4)] and p-X-C6F4-C[triple bond]C-C6H5[X=I (5), Br (6)] have been prepared via palladium-catalysed Sonogashira cross-coupling, or for X=Cl (7), by nucleophilic aromatic substitution reactions. The single-crystal X-ray structures of 1-3 and 5-6 have been determined. The structures reveal that the molecular packing is characterized by either arene-perfluoroarene interactions (3), or halogen-halogen interactions (isomorphous 1 and 2), or neither (isomorphous 5 and 6). The structure of represents the first fully determined crystal structure of a compound that contains a halogen atom other than fluorine, in which arene-perfluoroarene interactions are present.

  18. The Higgs-Boson Decay $H\\to gg$ to Order $\\alpha_s^5$ under the mMOM-Scheme

    CERN Document Server

    Zeng, Dai-Min; Wu, Xing-Gang; Shen, Jian-Ming

    2015-01-01

    We study the decay width of the Higgs-boson $H\\to gg$ up to order $\\alpha_s^5$ under the minimal momentum space subtraction scheme (mMOM-scheme). To improve the accuracy of perturbative QCD prediction, we adopt the principle of maximum conformality (PMC) to set its renormalization scales. A detailed comparison of the total decay width and the separate decay widths at each perturbative order before and after the PMC scale setting is presented. The PMC adopts the renormalization group equation to fix the optimal scales of the process. After the PMC scale setting, the scale-dependence for both the total and the separate decay widths are greatly suppressed, and the convergence of perturbative QCD series is improved. By taking the Higgs mass $M_H=125.09\\pm 0.21\\pm 0.11$ GeV, as recently given by the ATLAS and CMS collaborations, we predict $\\Gamma(H\\to gg)|_{\\rm mMOM, PMC} = 339.1\\pm 1.7^{+4.0}_{-2.4}$ keV, where the first error is for Higgs mass and the second error is the residual scale dependence by varying the...

  19. 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.

  20. Atmospheric test of the J(BrONO2/kBrO+NO2 ratio: implications for total stratospheric Bry and bromine-mediated ozone loss

    Directory of Open Access Journals (Sweden)

    B. Werner

    2012-10-01

    Full Text Available We report on time-dependent O3, NO2 and BrO profile measurements taken in the stratosphere by limb observations of scattered skylight at high-latitudes during autumn circulation turn-over. The observations are complemented by simultaneous direct solar occultation measurements around sunset and sunrise performed aboard the same stratospheric balloon payload. Supporting radiative transfer and photochemical modelling indicates that, the measurements can be used to constrain the ratio J(BrONO2/kBrO+NO2, for which overall a 1.69 ± 0.04 larger ratio is found than indicated by the most recent JPL compilation (Sander et al., 2011. Sensitivity studies reveal the major reasons likely to be (1 a larger BrONO2 absorption cross-section σBrONO2, primarily for wavelengths larger than 300 nm, and (2 a smaller kBrO+NO2 at 220 K than given by Sander et al. (2011. Other factors, e.g. the actinic flux and quantum yield for the dissociation of BrONO2, can be ruled out. The observations also have consequences for total inorganic stratospheric bromine (Bry estimated from stratospheric BrO measurements at high NOx loadings, since the J(BrONO2/kBrO+NO2 ratio largely determines the stratospheric BrO/Bry ratio during daylight. Using the revised J(BrONO2/kBrO+NO2 ratio, total stratospheric Bry is likely to be 1.4 ppt smaller than previously estimated from BrO profile measurements at high NOx loadings. This brings estimates of total stratospheric bromine inferred from organic source gas measurements (i.e. CH3Br, the halons, CH2Br2, CHBr3, ... into closer agreement with estimates based on BrO observations (inorganic method. The consequences for stratospheric ozone due to the revised J(BrONO2/kBrO+NO2 ratio are small (maximum −0.8%, since at high NOx (for which most Bry assessments are made an overestimated Bry using the inorganic method would in return almost cancel out with the amount of reactive bromine calculated in the photochemical models.

  1. Experimental and Theoretical Study of the Feasibility of the Gunn Effect in BiSCl, BiSBr, BiSI, BiSeI, BiSeBr and BiSeCl.

    Science.gov (United States)

    1981-03-01

    BiSI has been measured with photon energy, from .2 ~e. to 3.6 eV. The band structures of BiSBr, BiSCI, BiSebr, BiSeCl and BiSel have 0.... been...ANDTIEORETICAL_,TUDY OF THE IASIBILITY OF TII-U EFFECT IN BI tlBiSBr, BISI, BiSel , WTSeBr ANWD BiSeCI* q ri1na Scientific Repot7- /t , .by J...measured with photon energy, lio, from 2.2 to 3.6 eV. The band structures of BiSBr, BiSCI, BiSI, BiSeBr, BiSeCI and BiSel have been calculated by using the

  2. The CsBr-AlBr3 Phase Diagram and The Crystal Structure of CsAlBr4

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    1997-01-01

    The phase diagram in the CsBr-AlBr3 system has been reinvestigated. An adjusted liquidus diagram is given, showing the compound CsAlBr4 which melts congruently at 360 oC. The lack of consistency among previous results is presumably due to the presence of oxide impurities formed by attack of bromide...

  3. 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...

  4. Thermal- and pressure-induced cooperative spin transition in the 2D and 3D coordination polymers {Fe(5-Br-pmd)z[M(CN)x]y} (M=AgI, AuI, NiII, PdII, PtII).

    Science.gov (United States)

    Agustí, Gloria; Gaspar, Ana Belén; Muñoz, M Carmen; Real, José Antonio

    2007-11-12

    A new family of cyanide-based spin-crossover polymers with the general formula {Fe(5-Br-pmd)z[M(CN)x]y} [M=AgI (1), AuI (2), NiII (3), PdII (4), PtII (5); 5-Br-pmd=5-bromopyrimidine; z=1 or 2, x=2 or 4, and y=2 or 1] have been synthesized and characterized using single-crystal X-ray diffraction (XRD), X-ray powder diffraction (XRPD), magnetic susceptibility measurements, and differential scanning calorimetry (DSC). At 293 K, compound 1 presents the monoclinic space group C2/c, whereas at 120 K, it changes to the monoclinic space group P21/c. At 293 K, the crystal structure of 1 displays an uninodal three-dimensional network whose nodes, constituted of FeII, lie at the inversion center of an elongated octahedron. The equatorial bond lengths are defined by the N atoms of four [AgI(CN)2]- groups belonging to two crystallographically nonequivalent AgI atoms, Ag(1) and Ag(2). They are shorter than those of the axial positions occupied by the N atoms of the 5-Br-pmd ligands. The Fe-N average bond length of 2.1657(7) A is consistent with a high-spin (HS) state for the FeII ions. At 120 K, the crystal structure changes refer mainly to the FeII environment. There are two crystallographically independent FeII ions at this temperature, Fe(1) and Fe(2), which adopt the HS and low-spin (LS) states, respectively. The average Fe-N bond length for Fe(1) [2.174(5) A] and Fe(2) [1.955(5) A] agrees well with the reported magnetic data at this temperature. The spin transition of the FeII ions labeled as Fe(1) is found to be centered at Tc downward arrow=149 K and Tc upward arrow=167 K and accompanied by a drastic change of color from orange (HS) to red (LS). Magnetic susceptibility measurements under applied hydrostatic pressure performed on 1 have shown a linear displacement of the transition to higher temperatures while the hysteresis width remains unaltered in the interval of pressures of 105 Pa to 0.34 GPa. A further increase of the pressure induces the spin transition in the Fe(2

  5. A new <i>Consolida> subspecies from Anatolia

    Directory of Open Access Journals (Sweden)

    Misirdali, H.

    1990-12-01

    Full Text Available A new subspecies from Anatolia. <i>Consolida> hellesponticai> (Boiss. Chater subsp. <i>rosea> Misirdali & Ilarslan <i>subsp. novai>, is described.<br>>[ca] Es descriu una nova subspècie d'Anatòlia, <i>Consolida> hellesponticai> (Boiss. Chater subsp. <i>rosea> Misirdali & Ilarslan <i>subsp. novai>

  6. All-optical sub-ps switching and parallel logic gates with bacteriorhodopsin (BR) protein and BR-gold nanoparticles

    Science.gov (United States)

    Roy, Sukhdev; Yadav, Chandresh

    2014-12-01

    We propose a model for the early sub-picosecond (sub-ps) transitions in the photochromic bacteriorhodopsin (BR) protein photocycle (B570 → H → I460 → J625 → B570) and present a detailed analysis of ultrafast all-optical switching for different pump-probe combinations. BR excitation with 120 fs pump pulses at 570 or 612 nm results in the switching of cw probe beams at 460 and 580 nm exhibiting reverse saturable absorption (RSA) and saturable absorption (SA) respectively. The effect of pump intensity, pump pulse width, lifetime of I460 state, thickness and concentration on switching has been studied in detail. It is shown that low intensity (MW cm-2), high contrast (100%), sub-ps all-optical switching can be achieved with BR-gold nanoparticle solutions. The validity of the proposed model is evident from the good agreement of theoretical simulations with reported experimental results. The switching characteristics have been optimized to design ultrafast all-optical parallel NOT, OR, AND and the universal NOR and NAND logic gates. High contrast, ultrafast switching at relatively lower pump intensities, compared to other organic molecules, opens up exciting prospects for ultrafast, all-optical information processing with BR and BR nano-biophotonic hybrid materials.

  7. Peter Griffenfeld og brødrene Resen

    DEFF Research Database (Denmark)

    Olden-Jørgensen, Sebastian

    2000-01-01

    Med udgangspunkt i moderne teorier om klientelisme gives eksempler på relevansen af denne indfaldsvinkel til den tidlige enevældes politiske kultur. Eksemplet er Peter Griffenfelds forhold til brødrene Resen, og et par breve med relation til Resens Atlas aftrykkes....

  8. Br2, BrCl, BrO and surface ozone in coastal Antarctica: a meteorological and chemical analysis

    Directory of Open Access Journals (Sweden)

    R. von Glasow

    2012-04-01

    Full Text Available There is much debate over the source of bromine radicals in the atmosphere that drives polar boundary layer ozone depletion events (ODEs, but there is strong evidence to suggest a source associated with the sea ice zone. Here we report the first high temporal resolution measurements of Br2, BrCl and BrO in coastal Antarctica, made using a Chemical Ionisation Mass Spectrometer (CIMS. Mixing ratios ranged from instrumental detection limits to 13 pptv for BrO, 45 pptv for Br2, and 6 pptv for BrCl. We find evidence for blowing snow as a source of reactive bromine both directly during a storm and subsequently from recycling of bromide deposited on the continental snowpack. An unusual event of trans-continental air mass transport might have been responsible for severe surface ozone depletion observed at Halley. The halogen source region was the Bellingshausen Sea, to the west of the Antarctic Peninsula, the air mass having spent 3 1/2 days in complete darkness prior to arrival at Halley. We, further, identify an artefact in daytime BrCl measurements arising from conversion of HOBr, similar to that already identified for CIMS observations of Br2. Model calculations using the MISTRA 0-D model suggest a 50–60% conversion of HOBr to Br2, and 5–10% conversion to BrCl. Careful data filtering enabled us to use the halogen observations, in conjunction with the MISTRA model, to explore the temperature dependence of the Br2:BrCl ratio. We find evidence of a ratio shift towards Br2 at temperatures below ~−21 °C, suggesting a relationship with hydrohalite (NaCl.2H2O precipitation. This suite of Antarctic data provides the first analogue to similar measurements made in the Arctic.

  9. Comunicação táctil para todo público: sistema braille usando verniz poli(metacrilato de metila) em relevo polimerizável por ultravioleta (UV) impresso junto com texto e imagens em tinta (i-Br/Vza-UVxmf)

    OpenAIRE

    Sanclemente, José Manuel Hernández

    2013-01-01

    O presente trabalho apresenta uma inovação (invenção) aplicada como uma ferramenta de inclusão à educação e de acessibilidade entre pessoas deficientes visuais, que representam 6,98% da população brasileira (IBGE, 2002). Propõe-se a impressão simultânea usando o sistema Braille tradicional aplicado com verniz poli(metacrilato de metila) em relevo polimerizável por ultravioleta (UV) junto com impressão tradicional em tinta (por exemplo, offset); sendo denominado pelo autor como i-Br/Vza-UVxmf ...

  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. Notat vedr. energisystemer og brændeovne

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad

    2008-01-01

    nedbringe CO2‐udslippet med 1,8 mio. ton. Hvis vi forestiller os, at kun den del, der er registreret i statistikker mv. i 2006 erstattes, dvs. ca. 9 PJ, vil vi kunne undgå ca. 0,9 mio. ton CO2 ved ovennævnte omstilling. Også hvis vi udskifter brændeovne uden for fjernvarmeområder med naturgasfyr vil...

  12. Ubiquitous production of branched glycerol dialkyl glycerol tetraethers (brGDGTs) in global marine environments: a new source indicator for brGDGTs

    Science.gov (United States)

    Xiao, Wenjie; Wang, Yinghui; Zhou, Shangzhe; Hu, Limin; Yang, Huan; Xu, Yunping

    2016-10-01

    Presumed source specificity of branched glycerol dialkyl glycerol tetraethers (brGDGTs) from bacteria thriving in soil/peat and isoprenoid GDGTs (iGDGTs) from aquatic organisms led to the development of several biomarker proxies for biogeochemical cycle and paleoenvironmental reconstructions. However, recent studies reveal that brGDGTs are also produced in aquatic environments besides soils and peat. Here we examined three cores from the Bohai Sea, and found distinct difference in brGDGT compositions varying with the distance from the Yellow River mouth. We thus propose an abundance ratio of hexamethylated to pentamethylated brGDGT (IIIa / IIa) to evaluate brGDGT sources. The compilation of globally distributed 1354 marine sediments and 589 soils shows that the IIIa / IIa ratio is generally soils and 0.59-0.92 and > 0.92 in marine sediments with and without significant terrestrial inputs, respectively. Such disparity confirms the existence of two sources for brGDGTs, a terrestrial origin with lower IIIa / IIa and a marine origin with higher IIIa / IIa, which is likely attributed to a generally higher pH and the production of brGDGTs in cold deep water in marine waters. The application of the IIIa / IIa ratio to the East Siberian Arctic Shelf proves it to be a sensitive source indicator for brGDGTs, which is helpful for accurate estimation of organic carbon source and paleoclimates in marine settings.

  13. Phase diagram of the CsBr-CaBr2 system

    Institute of Scientific and Technical Information of China (English)

    BAO Xinhua; CHEN Nianyi; LU Wencong; CHENG Zhixuan; LUO Yunyun; LU Weiying; XIA Yiben

    2006-01-01

    The phase diagram of the CsBr-CaBr2 system was re-determined by using differential thermal analysis and high temperature and room temperature X-ray diffraction analysis. It is concluded that there are three intermediate compounds in this system: a congruently melting compound, CsCaBr3, with a melting point of 823℃ and two incongruently melting compounds, Cs2CaBr4 and Cs3Ca2Br7, whose peritectic points being 597℃ and 635℃, respectively. X-ray diffraction analysis indicated that compound CsCaBr3 is of slightly distorted perovskite structure.

  14. 81Br NQR for Uncoordinated Br ions in trans-[CoBr2(en)2][H5O2]Br2 and trans-[CoBr2(en)2] [D5O2]Br2

    Science.gov (United States)

    Honda, H.; Sasane, A.; Miyagi, K.; Ishikawa, A.; Mori, Y.

    1994-02-01

    The temperature dependence of the 81Br NQR frequencies (vD) for uncoordinated Br- ions in trans-[CoBr2(en)2] [D5O2]Br2(D) has been determined by a continuous-wave spectrometer. vD amounted to 16.200 MHz at 273 K. This is lower by 418 kHz than the 81Br NQR frequency (vH) for trans-[CoBr2 (en2] [H5O2 ]Br2 (H). The frequency difference (Δv = vH -vD) remained almost constant in the temperature range studied. A shortening of the O-H bond length caused by deuteration could explain the magnitude and the sign of Av on the basis of a point charge model calculation. The compounds D and H yielded 81Br NQR lines in the range 110-320 K and 90-343 K, respectively. As to the 59Co NQR frequencies (7/2 - 5/2), the observed isotope frequency shifts (Δv1 = v1H - v1D) between D and H were smaller than 5 kHz. Below 160 K, 59Co resonances were only available by pulsed experiments. 59Co NQR spin-lattice relaxation times T1Q of 0.54 ms at 194 K and 4.8 s at 77 K for H have been observed.

  15. Photoinduced Br Desorption from CsBr Thin Films Grown on Cu(100)

    Energy Technology Data Exchange (ETDEWEB)

    Halliday, Matthew T.; Joly, Alan G.; Hess, Wayne P.; Shluger, AL

    2015-10-22

    Thin films of CsBr deposited onto metals such as copper are potential photocathode materials for light sources and other applications. We investigate desorption dynamics of Br atoms from CsBr films grown on insulator (KBr, LiF) and metal (Cu) substrates induced by sub-bandgap 6.4 eV laser pulses. The experimental results demonstrate that the peak kinetic energy of Br atoms desorbed from CsBr/Cu films is much lower than that for the hyperthermal desorption from CsBr/LiF films. Kelvin probe measurements indicate negative charge at the surface following Br desorption from CsBr/Cu films. Our ab initio calculations of excitons at CsBr surfaces demonstrate that this behavior can be explained by an exciton model of desorption including electron trapping at the CsBr surface. Trapped negative charges reduce the energy of surface excitons available for Br desorption. We examine the electron-trapping characteristics of low-coordinated sites at the surface, in particular, divacancies and kink sites. We also provide a model of cation desorption caused by Franck-Hertz excitation of F centers at the surface in the course of irradiation of CsBr/Cu films. These results provide new insights into the mechanisms of photoinduced structural evolution of alkali halide films on metal substrates and activation of metal photocathodes coated with CsBr.

  16. Hydrogen for X-group exchange in CH3X, X = Cl, Br, I, OMe and NMe2 byMonomeric [1,2,4-(Me3C)3C5H2]2CeH: Experimental and Computational Support for a Carbenoid Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Werkema, Evan; Andersen, Richard; Yahia, Ahmed; Maron, Laurent; Eisenstein, Odile

    2009-05-15

    The reaction between [1,2,4-(Me3C)3C5H2]2CeH, referred to as Cp'2CeH, andCH3X where X is Cl, Br, I, OMe and NMe2, are described. The reactions fall intothree distinct classes. Class a, where X = Cl, Br and I rapidly form Cp'2CeX and CH4without formation of identifiable intermediates in the 1H NMR spectra. Class b, whereX = OMe proceeds rapidly to Cp'2Ce(eta2-CH2OMe) and H2 and then to Cp'2CeOMeand CH4. The methoxymethyl derivative is sufficiently stable to be isolated andcharacterized and it is rapidly converted to Cp'2CeOMe in presence of BPh3. Class c,where X = NMe2 does not result in formation of Cp'2CeNMe2, but deuterium labelingexperiments show that H for D exchange occurs in NMe3. Density functionalcalculations DFT(B3PW91) on the reaction of (C5H5)2CeH, referred to as Cp2CeH,and CH3X show that the barrier for alpha-CH activation, resulting in formation ofCp2Ce(eta2-CH2X), proceeds with a relatively low activation barrier (DeltaG++) but thesubsequent ejection of CH2 and trapping by H2 has a higher barrier; the height of thesecond barrier lies in the order F, Cl, Br, I< OMe<< NMe2, consistent with theexperimental studies. The DFT calculations also show that the two-step reaction,which proceeds through a carbenoid intermediate, has a lower barrier than a directone-step sigma bond metathesis mechanism. The reaction of Cp2CeCH2OMe and BPh3 is calculated to be a low barrier process and the ylide, CH2(+)BPh3(-), is a transition state and not an intermediate.

  17. Hydrogen for X-group exchange in CH3X, X = Cl, Br, I, OMe and NMe2 byMonomeric [1,2,4-(Me3C)3C5H2]2CeH: Experimental and Computational Support for a Carbenoid Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Werkema, Evan; Andersen, Richard; Yahia, Ahmed; Maron, Laurent; Eisenstein, Odile

    2009-05-15

    The reaction between [1,2,4-(Me3C)3C5H2]2CeH, referred to as Cp'2CeH, andCH3X where X is Cl, Br, I, OMe and NMe2, are described. The reactions fall intothree distinct classes. Class a, where X = Cl, Br and I rapidly form Cp'2CeX and CH4without formation of identifiable intermediates in the 1H NMR spectra. Class b, whereX = OMe proceeds rapidly to Cp'2Ce(eta2-CH2OMe) and H2 and then to Cp'2CeOMeand CH4. The methoxymethyl derivative is sufficiently stable to be isolated andcharacterized and it is rapidly converted to Cp'2CeOMe in presence of BPh3. Class c,where X = NMe2 does not result in formation of Cp'2CeNMe2, but deuterium labelingexperiments show that H for D exchange occurs in NMe3. Density functionalcalculations DFT(B3PW91) on the reaction of (C5H5)2CeH, referred to as Cp2CeH,and CH3X show that the barrier for alpha-CH activation, resulting in formation ofCp2Ce(eta2-CH2X), proceeds with a relatively low activation barrier (DeltaG++) but thesubsequent ejection of CH2 and trapping by H2 has a higher barrier; the height of thesecond barrier lies in the order F, Cl, Br, I< OMe<< NMe2, consistent with theexperimental studies. The DFT calculations also show that the two-step reaction,which proceeds through a carbenoid intermediate, has a lower barrier than a directone-step sigma bond metathesis mechanism. The reaction of Cp2CeCH2OMe and BPh3 is calculated to be a low barrier process and the ylide, CH2(+)BPh3(-), is a transition state and not an intermediate.

  18. 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.

  19. Enhanced electrical transport and phase diagram of LiBr-NaBr mixed crystal system

    Energy Technology Data Exchange (ETDEWEB)

    Manoravi, P.; Shahi, K. (Dept. of Physics, Indian Inst. of Tech., Kanpur (India))

    1992-12-01

    The ionic conductivity and the phase diagram of LiBr-NaBr system has been studied. Maximum conductivity enhancement by factors of 2.8 and 2.3x10[sup 4] with respect to pure LiBr and NaBr, respectively are obtained at 400degC for Li[sub 0.7]Na[sub 0.3]Br solid solution. The demixing curve of the phase diagram which was constructed from the conductivity versus temperature studies, suggest that the LiBr-NaBr system forms complete solid solution only above 215degC. The conductivity enhancements and the activation energies are consistent with the melting curve of the phase diagram. (orig.).

  20. Characterization of soluble bromide measurements and a case study of BrO observations during ARCTAS

    Directory of Open Access Journals (Sweden)

    J. Liao

    2012-02-01

    Full Text Available A focus of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS mission was examination of bromine photochemistry in the spring time high latitude troposphere based on aircraft and satellite measurements of bromine oxide (BrO and related species. The NASA DC-8 aircraft utilized a chemical ionization mass spectrometer (CIMS to measure BrO and a mist chamber (MC to measure soluble bromide. We have determined that the MC detection efficiency to molecular bromine (Br2, hypobromous acid (HOBr, bromine oxide (BrO, and hydrogen bromide (HBr as soluble bromide (Br was 0.9±0.1, 1.06+0.30/−0.35, 0.4±0.1, and 0.95±0.1, respectively. These efficiency factors were used to estimate soluble bromide levels along the DC-8 flight track of 17 April 2008 from photochemical calculations constrained to in situ BrO measured by CIMS. During this flight, the highest levels of soluble bromide and BrO were observed and atmospheric conditions were ideal for the space-borne observation of BrO. The good agreement (<i>R>2 = 0.76; slope = 0.95; intercept = −3.4 pmol mol−1 between modeled and observed soluble bromide, when BrO was above detection limit (>2 pmol mol−1 under unpolluted conditions (NO<10 pmol mol−1, indicates that the CIMS BrO measurements were consistent with the MC soluble bromide and that a well characterized MC can be used to derive mixing ratios of some reactive bromine compounds. Tropospheric BrO vertical column densities (BrOVCD derived from CIMS BrO observations compare well with BrOTROPVCD from OMI on 17 April 2008.

  1. Tony Blair satub täna Brüsselis Saksa ja Prantsuse surve alla / Maris Lillak

    Index Scriptorium Estoniae

    Lillak, Maris, 1970-

    2004-01-01

    EL-i liikmesriikide algaval tippkohtumisel Brüsselis loodetakse kokku leppida EL-i uue põhiseaduse osas. Suurbritannia peaministri Tony Blairi ettepanekutest. Vt. samas Marit Ruuda art. "Põhiseadus ootab uut punkti"

  2. Tony Blair satub täna Brüsselis Saksa ja Prantsuse surve alla / Maris Lillak

    Index Scriptorium Estoniae

    Lillak, Maris, 1970-

    2004-01-01

    EL-i liikmesriikide algaval tippkohtumisel Brüsselis loodetakse kokku leppida EL-i uue põhiseaduse osas. Suurbritannia peaministri Tony Blairi ettepanekutest. Vt. samas Marit Ruuda art. "Põhiseadus ootab uut punkti"

  3. 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…

  4. Phase topology of a NR/BR elastomer blend with active filler

    Directory of Open Access Journals (Sweden)

    Plavšić Milenko B.

    2003-01-01

    Full Text Available The relations between the structure and mechanical properties of a polymer blend of natural (NR and polybutadiene (BR rubber (i.e. a NR/BR blend with the weight ratio of the components 70/30 filled with active carbon black were analysed. The properties of the individual phases in the blend were resolved by modeling the stress-strain relationship according to the Bauer procedure for high extensions. The obtained results indicated that BR is the dispersed phase, having a higher modulus, which was also confirmed by the much better fit of the experimental data to the series type of phase coupling according to the Takanayagy theory.

  5. Two-dimensional (2+n) REMPI of CH(3)Br: photodissociation channels via Rydberg states.

    Science.gov (United States)

    Kvaran, Agúst; Wang, Huasheng; Matthíasson, Kristján; Bodi, Andras

    2010-09-23

    (2+n) resonance enhanced multiphoton ionization (REMPI) spectra of CH(3)Br for the masses H(+), CH(m)(+), (i)Br(+), H(i)Br(+), and CH(m)(i)Br(+) (m = 0-3; i = 79, 81) have been recorded in the 66 000-81 000 cm(-1) resonance energy range. Signals due to resonance transitions from the zero vibrational energy level of the ground state CH(3)Br to a number of Rydberg states [Ω(c)]nl;ω (Ω(c) = 3/2, 1/2; ω = 0, 2; l = 1(p), 2(d)) and various vibrational states were identified. C((3)P) and C*((1)D) atom and HBr intermediate production, detected by (2+1) REMPI, most probably is due to photodissociation of CH(3)Br via two-photon excitations to Rydberg states followed by an unusual breaking of four bonds and formation of two bonds to give the fragments H(2) + C/C* + HBr prior to ionization. This observation is supported by REMPI observations as well as potential energy surface (PES) ab initio calculations. Bromine atom production by photodissociation channels via two-photon excitation to Rydberg states is identified by detecting bromine atom (2+1) REMPI.

  6. Ligand and substrate effects in gas-phase reactions of NiX(+)/RH couples (X=F, Cl, Br, I; R=CH3, C2H5, nC3H7, nC4H9).

    Science.gov (United States)

    Schlangen, Maria; Schröder, Detlef; Schwarz, Helmut

    2007-01-01

    The reactions of small saturated hydrocarbons by gaseous nickel cations NiX+ (X=F, Cl, Br, I) are investigated by means of electrospray ionization mass spectrometry. The halide cations are obtained from solutions of the corresponding Ni(II) salts in water or methanol as solvents. NiF+ is the only Ni(II) halide complex that brings about thermal activation of methane. The branching ratios of the observed reactions with C2H6, C3H8, and nC4H10 are shifted systematically by changing the nature of both the ligand X and the substrate RH. In the elimination of HX (X=F, Cl, Br, I), the formal oxidation state of the metal ion appears to be conserved, and the importance of this reaction channel decreases in going from NiF+ to NiI+. A reversed trend is observed in the losses of small closed-shell neutral molecules, that is, H2, CH4 and C2H6, which dominate the gas-phase ion chemistry of NiI+/RH couples. Additionally, inner-sphere electron-transfer reactions take place for a few systems, that is, the delivery of hydride or methanide ions from the hydrocarbon to NiX+ in the course of which the hydrocarbon is converted to a carbenium ion and the cationic metal complex gives rise to a neutral RNiX molecule (R=H, CH3). This process gains importance with decreasing atomic number of the halides and with increasing the size of the alkane. Thus, it constitutes the major pathway in the reactions of NiF+ with propane and n-butane, whereas it is not observed for any of the NiI+/RH couples investigated. Concerning the regioselectivity of the reactions with propane and n-butane, heterolytic cleavage of secondary carbon--hydrogen bonds is clearly preferred compared to that of primary ones, as revealed by deuterium labeling studies. For the NiF+/C3H8 couple, the selectivity of the hydride transfer is as large as 360 in favor of the secondary positions. Though smaller, large preferences for the activation of secondary C--H bonds are also operative in homolytic bond activation of RH (R=nC3H7, n

  7. 电动势法测定混合电解质CsBr+NaBr+H2O体系的活度系数%Electromotiye force measurements of activity coefficients for the ternary system (CsBr + NaBr + H2O)

    Institute of Scientific and Technical Information of China (English)

    谢培培; 李淑妮; 翟全国; 蒋育澄; 胡满成

    2013-01-01

    Activity coefficients of the ternary system (CsBr + NaBr + H2O) were determined by electromotive force (EMF) measurements using the cell: Cs-ion selective electrode(ISE) | CsBr (mA), NaBr (mB) | Br-ion selective electrode (ISE) at 298. 15 K, and over total ionic strengths from range 0. 01 to 1. 0 mol/kg for different ionic strength fractions (0. 25, 0. 5 and 0. 75). The experimental data were satisfactorily described via the Pitzer and Harned models. The Pitzer binary and ternary ionic interaction parameters and the Harned parameters have also been calculated.%采用电池Cs-ISE | CsBr(mA),NaBr (mB)| Br-ISE测定了298.15 K温度下CsBr+NaBr+H2O体系在离子强度I=0.01~1.00 mol/kg范围内,离子强度分数yB=0,0.25,0.50和0.75时的电动势,实验结果分别用Pitzer方程和Harned经验公式进行拟合,得到该体系的Pitzer二离子、三离子相互作用参数和Harned参数.拟合结果表明,Pitzer方程和Harned经验公式均能理想地适用于该三元盐水体系.

  8. DNA staining with the fluorochromes EtBr, DAPI and YOYO-1 in the comet assay with tobacco plants after treatment with ethyl methanesulphonate, hyperthermia and DNase-I.

    Science.gov (United States)

    Gichner, Tomás; Mukherjee, Anita; Velemínský, Jirí

    2006-06-16

    We applied the alkaline version of the single-cell gel electrophoresis (comet) assay to roots and leaves of tobacco (Nicotiana tabacum var. xanthi) seedlings or isolated leaf nuclei treated with: (1) the alkylating agent ethyl methanesulphonate, (2) necrotic heat treatments at 50 degrees C, and (3) DNase-I. All three treatments induced a dose-dependent increase in DNA migration, expressed as percentage of tail DNA. A comparison of the fluorochrome DNA dyes ethidium bromide, DAPI and YOYO-1 demonstrated that for the alkaline version of the comet assay in plants, the commonly used fluorescent dye ethidium bromide can be used with the same efficiency as DAPI or YOYO-1.

  9. Ammonium dynamics in the disordered alpha-phase of K sub 1 sub - sub x (NH sub 4) sub x Y (Y = Cl, Br, I). A neutron scattering study

    CERN Document Server

    Natkaniec, I; Smirnov, L S

    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 alpha-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 sub 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 sub 1 sub - sub x (NH sub 4) sub x I mixed salts. The harmonic excitations of ammonium in a hypothetical low-temperature alpha-phase of NH sub 4 I are approximated...

  10. Synthesis of [MoOS3Cu3U(3,5-diMePy)4]·CH3CN and(Et4N)4[Mo4Cu8O4S12{(Ph2PS)2N}4]from Solid State Product[Et4N]4[Mo2O2S6Cu6I4Br2]%从固相反应产物[NEt4]4[Mo2O2S6Cu6I4Br2]合成原子簇[MoOS3Cu3I(3,5-diMePy)4]·CH3CN和(EtN)4[Mo4Cu8O4S12{(Ph2PS)2}4](英文)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Treatment of iodide-bridged dimer [NEt4] 4[Mo2O2S6Cu6I4Br2] 1 with 3, 5-bimethylpyridine or with K[(Ph2PS) 2N] in CH3CN afforded the tetranuclear cluster [MoOS3Cu3I(3,5-diMePy)4]·CH3CN 2 and dodecanuclear cluster (Et4N)4[Mo4Cu8O4S12{(Ph2PS)2N}4] 3. Monomeric 2 possess a nest-shaped skeleton.The structure of oligomeric 3 can be regarded as a tetramer of nest-shaped MoCu3OS3[(Ph2PS)aN]groups co-polymerized by sharing the limbic Cu atoms.

  11. 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.

  12. Fabrication of TlBr Detector

    Institute of Scientific and Technical Information of China (English)

    HAO; Xiao-yong

    2015-01-01

    1 Introduction Thallium bromide(TlBr)is an attractive compound semiconductor material for fabrication of room temperature radiation detectors due to its characteristics of wide band-gap energy,high density,high atomic numbers.It can be used in the fields of security detection,imaging and radiation protection.

  13. A Possible Reaction Channel from BrONO to BrNO2

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A possible isomerization channel from BrONO (bromine nitrite) to BrNO2 (nitryl bromide) is predicted by means of MP2 and QCISD(T) (single-point) methods. The channel is a direct bromine abstraction reaction from BrONO molecule by NO2 in which the forward reaction barrier is 89.30 kJ/mol at final UQCISD(T)/6-311+G(2df)//UMP2/6-311G(d) level of theory with zero-point energies included. The result can explain the available experiments very well.

  14. The Controlling Mechanism for Potential Loss in CH3NH3PbBr3 Hybrid Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Xiaojia; Chen, Bo; Yang, Mengjin; Wu, Congcong; Orler, Bruce; Moore, Robert B.; Zhu, Kai; Priya, Shashank

    2016-08-12

    We investigated moisture and thermal stability of MAPbBr3 perovskite material. Cubic MAPbBr3 was found to be moisture-insensitive and can avoid the thermal stability issues introduced by low-temperature phase transition in MAPbI3. MAPbBr3 and MAPbI3 hybrid solar cells with efficiencies of ~7.1% and ~15.5%, respectively, were fabricated, and we identified the correlation between the working temperature, light intensity, and the photovoltaic performance. No charge-carrier transport barriers were found in the MAPbBr3 and MAPbI3 solar cells. The MAPbBr3 solar cell displays a better stability under high working temperature because of its close-packed crystal structure. Temperature-dependent photocurrent-voltage characteristics indicate that, unlike the MAPbI3 solar cell with an activation energy (EA) nearly equal to its band gap (Eg), the EA for the MAPbBr3 solar cell is much lower than its Eg. This indicates that a high interface recombination process limits the photovoltage and consequently the device performance of the MAPbBr3 solar cell.

  15. Geometrical structures, vibrational frequencies, force constants and dissociation energies of isotopic water molecules (H2O, HDO, D2O, HTO, DTO, and T2O) under dipole electric field

    Institute of Scientific and Technical Information of China (English)

    Shi Shun-Ping; Zhang Quan; Zhang Li; Wang Rong; Zhu Zheng-He; Jiang Gang; Fu Yi-Bei

    2011-01-01

    The dissociation limits of isotopic water molecules are derived for the ground state. The equilibrium geometries,the vibrational frequencies, the force constants and the dissociation energies for the ground states of all isotopic water molecules under the dipole electric fields from -0.05 a.u. to 0.05 a.u. are calculated using B3P86/6-311++G(3df,3pf).The results show that when the dipole electric fields change from -0.05 a.u. to 0.05 a.u., the bond length of H-O increases whereas the bond angle of H-O-H decreases because of the charge transfer induced by the applied dipole electric field. The vibrational frequencies and the force constants of isotopic water molecules change under the influence of the strong external torque. The dissociation energies increase when the dipole electric fields change from -0.05 a.u.to 0.05 a.u. and the increased dissociation energies are in the order of H2O, HDO, HTO, D2O, DTO, and T2O under the same external electric fields.

  16. 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")

  17. 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")

  18. Optical properties and electronic structure of BiTeCl and BiTeBr compounds

    Science.gov (United States)

    Makhnev, A. A.; Nomerovannaya, L. V.; Kuznetsova, T. V.; Tereshchenko, O. E.; Kokh, K. A.

    2016-09-01

    Optical properties of BiTeCl and BiTeBr compounds with a strong Rashba spin-orbit coupling are studied in the 0.08-5.0 eV range using the optical ellipsometry method. Fundamental characteristics of the electronic structure are obtained. Similarly to BiTeI, spectra of the imaginary part of dielectric permittivity constant ɛ2( E) in the energy interval between the plasma edge and the threshold of an intense interband absorption (0.7 eV in BiTeCl and 0.6 eV in BiTeBr) display a fine structure of electronic transitions at 0.25 and 0.55 eV in BiTeCl and 0.20 and 0.50 eV in BiTeBr. These features are assigned to electronic transitions between the bulk conduction zones split by the Rashba spin-orbit interaction. The parameters of the electronic structure of BiTeCl and BiTeBr are compared with the BiTeI compound that was studied earlier. In the BiTeCl-BiTeBr-BiTeI row, the absorption edge and main features of the fundamental absorption exhibit a shift to low energies.

  19. Bromine-79 NQR for uncoordinated Br- ions in trans-[CoBr2(en)2][H5O2]Br2

    Science.gov (United States)

    Sasane, A.; Matsuda, T.; Honda, H.; Mori, Y.

    1992-02-01

    A single 79Br NQR line showing a frequency of 19.594 MHz at room temperature has been observed in the crystals of trans-[CoBr2(en)2] [ H5O2 ] Br2 and assigned to the Br - ions which are not coordinated to the central Co(III) atom. The electric field gradient (EFG) at the Br - nuclei arises from O-H • • • Br - hydrogen bond formation between the Br - ions and the terminal O - H hydrogen atoms in [ H5O2 ] + ions. The induced EFG is greater for the present bromine complex than that for the isostructural chlorine complex. A point charge model calculation explains well the relative magnitude of the EFG in the two crystals by introducing Sternheimer's antishielding factors for the halogen ions.

  20. Experimental studies on BrO/Br ratios at Stromboli, Etna, Masaya, Gorely and Nyiragongo

    Science.gov (United States)

    Bobrowski, Nicole; Wittmer, Julian; Liotta, Marcello; Calabrese, Sergio; Giuffrida, Giovanni; Brusca, Lorenzo; Platt, Ulrich

    2014-05-01

    Since the discovery of BrO in a volcanic plume (Bobrowski et al. 2003) many measurements have been performed as well as modelling to understand the radical chemistry in volcanic plumes, in particular, the interaction between volcanic gas species, released under strongly reduced conditions, and the oxidizing atmosphere. Besides the goal in atmospheric chemistry to better determine the impact of volcanic emission (e.g. reactive bromine) on the local (and maybe global) scale, volcanologists also have an interest to understand if the BrO/SO2 ratios can be used as a monitoring parameter giving further insides in dynamic processes of volcanoes. One of the major advantages when utilizing BrO/SO2 ratios is the relatively easiness of the measurements, which can be taken in a safe distance from volcanic activity accompanied by a good temporal resolution partly even during explosive eruptions. Recently, it has been shown (Lübcke et al., 2013) that already existing automatically running measurement networks can now be used to gain long-term data sets of BrO/SO2 ratios. However, one of the arguments which potentially makes volcanological interpretations difficult is the reactivity of BrO. Therefore it is, of great importance to link the measurements of BrO and gaseous hydrogen bromide to the total emission flux of bromine in order to estimate the pristine gas composition released from magmas. In particular, meteorological influences, trace gas composition of the surrounding atmosphere and the volcanic gas composition can all potentially effect the formation of BrO and might have to be considered. Some of these factors potentially also influence near source in-situ measurement. We need to answer the question: Can we correlate BrO measurements to the total bromine outgassing? Only with this knowledge we can relate changes of the measured gas ratios (BrO/SO2) to the volcanic fluids emitted by the underlying magma and can interpret data as signals from depth, which provide insight

  1. NY-BR-1 protein expression in breast carcinoma: a mammary gland differentiation antigen as target for cancer immunotherapy.

    Science.gov (United States)

    Theurillat, Jean-Philippe; Zürrer-Härdi, Ursina; Varga, Zsuzsanna; Storz, Martina; Probst-Hensch, Nicole M; Seifert, Burkhardt; Fehr, Mathias K; Fink, Daniel; Ferrone, Soldano; Pestalozzi, Bernhard; Jungbluth, Achim A; Chen, Yao-Tseng; Jäger, Dirk; Knuth, Alexander; Moch, Holger

    2007-11-01

    NY-BR-1 is a recently identified differentiation antigen of the mammary gland. To use NY-BR-1 for T-cell-based immunotherapy, analysis of its co-expression with HLA class I antigens is required. In the present tissue microarray study, primary breast cancers (n = 1,444), recurrences (n = 88), lymph node (n = 525) and distant metastases (n = 91) were studied for NY-BR-1 expression using a novel monoclonal antibody. NY-BR-1 expression was compared with prognosis, estrogen receptor, HER2-status, EGFR and HLA class I antigen expression. NY-BR-1 was more frequently expressed in grade 1 (82%) than in grade 2 (69%) and grade 3 (46%) carcinomas (P < 0.0001). Moreover, NY-BR-1 expression correlated directly with estrogen receptor expression (P < 0.0001) and inversely correlated with HER2-status and EGFR expression (P < 0.0001 for both). Considering high expression level of co-expression, 198/1,321 (15%) primary breast carcinomas and 4/65 (6%) distant metastases expressed NY-BR-1 and HLA class I, suggesting that active immunotherapy can be applied to about 10% of breast cancer patients. Survival analysis showed an association of NY-BR-1 expression with better patient outcome (P = 0.015). No difference between NY-BR-1 expression of primary tumors and metastases could be found, indicating that the presence of NY-BR-1 in metastases can be deduced from their corresponding primary. Forty-three paired biopsies taken from patients before and after chemotherapy suggest that NY-BR-1 expression is not influenced by preceding chemotherapy (kappa = 0.89, P < 0.0001). In summary, the co-expression of NY-BR-1 with HLA class I antigens and its expression in metastases without modification by chemotherapy suggest that NY-BR-1 targeted immunotherapy represents a viable strategy in addition to other targeted cancer drug therapies of breast cancer.

  2. Decommissioning of the BR3 PWR

    Energy Technology Data Exchange (ETDEWEB)

    Massaut, V.; Klein, M

    1998-07-01

    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.

  3. Energy Response of LaBr3

    Science.gov (United States)

    Ertürk, S.; Maj, A.; Ciemala, M.; Stezowski, O.; Courtin, S.; Strachan, J.; Kumar, S.; Paris Collaboration

    2012-09-01

    In recent years, important developments in scintillator technology have been made in the Lanthanum Halogen LaBr3 (Ce) crystal, which has high-energy separation, very good timing-properties and a stopping-power that can be used as a detector at room temperature. The international PARIS project will be created as a prototype of this detector system, which will be used in SPIRAL2 as a stand alone or in collaboration with the EXOGAM or AGATA detector array. A fusion evaporation reaction is used to produce exotic nuclei and is then transferred at a very high angular momentum to compound nuclei. Due to the accompanying high rotation, the exotic shape starts changing into vibrational and rotational collective phenomena which hitherto have together become difficult to detect and fully understand. In order to perform this type of research, in addition to conventional known gamma-ray detectors, high-efficiency gamma-ray detectors that can effectively identify gamma rays are also required as calorimeters. LaBr3 is planned to use such means. Results of ongoing analysis for energy and the time response of LaBr3 will be presented.

  4. Solid-state (79/81)Br NMR and gauge-including projector-augmented wave study of structure, symmetry, and hydration state in alkaline earth metal bromides.

    Science.gov (United States)

    Widdifield, Cory M; Bryce, David L

    2010-02-11

    Bromine-79/81 solid-state NMR (SSNMR) spectroscopy is established as a tool to characterize the local structure and symmetry about bromide ions in inorganic systems. Benchmark experimental (79/81)Br SSNMR data are acquired for CaBr(2), SrBr(2), BaBr(2), MgBr(2).6H(2)O, SrBr(2).6H(2)O, BaBr(2).2H(2)O, and CaBr(2).xH(2)O using the Solomon echo and/or QCPMG pulse sequences in magnetic fields of 11.75 and 21.1 T. Analytical line-shape analysis provides (79/81)Br electric field gradient (EFG) tensor parameters (including (79)Br quadrupolar coupling constants, C(Q)((79)Br), of up to 75.1(5) MHz in CaBr(2)), chemical shift tensor parameters (including the largest reported anisotropy), and the relative orientation of the tensor principal axis systems. These data are interpreted in terms of structure and symmetry. Our results indicate that ionic bromide systems should be generally accessible to characterization by (79/81)Br SSNMR despite sizable quadrupolar interactions. The resolving capabilities of (79/81)Br SSNMR spectroscopy are illustrated, using samples which possess up to four magnetically inequivalent sites, and through a rare example of (79)Br magic-angle spinning NMR for a Br in a noncubic lattice. Bromine-79/81 SSNMR spectroscopy is demonstrated to be sensitive to the presence of hydrates (i.e., pseudopolymorphism), via drastic changes in C(Q) and delta(iso). The changes are diagnostic to an extent that the composition of the mixture CaBr(2).xH(2)O is determined for the first time. This technique should therefore be applicable to characterize other unknown mixtures or polymorphs. Important instances where (79)Br nuclear quadrupole resonance data were found to be deficient are noted and corrected. GIPAW DFT computations are shown to be generally in very good agreement with the experimental (79/81)Br SSNMR observations. Finally, it is demonstrated that the origin of the EFG at the Br nuclei cannot be described quantitatively using a point charge model, even after

  5. 5-Br-PAN-6S的制备

    Institute of Scientific and Technical Information of China (English)

    任显钜; 周华凤

    2011-01-01

    本文合成了5-Br-PAN-6S,从α-氨基吡啶出发进行溴化得5-Br-2-氨基吡啶,在碱性条件下重氮化后,再与β-萘酚偶联得5-Br-PAN,在40-50℃的温度下,用发烟硫酸进行磺化生成5-Br-PAN-6S.

  6. 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.

  7. 3c/4e [small sigma, Greek, circumflex]-type long-bonding competes with ω-bonding in noble-gas hydrides HNgY (Ng = He, Ne, Ar, Kr, Xe, Rn; Y = F, Cl, Br, I): a NBO/NRT perspective.

    Science.gov (United States)

    Zhang, Guiqiu; Li, Hong; Weinhold, Frank; Chen, Dezhan

    2016-03-21

    Noble-gas hydrides HNgY are frequently described as a single ionic form (H-Ng)(+)Y(-). We apply natural bond orbital (NBO) and natural resonance theory (NRT) analyses to a series of noble-gas hydrides HNgY (Ng = He, Ne, Ar, Kr, Xe, Rn; Y = F, Cl, Br, I) to gain quantitative insight into the resonance bonding of these hypervalent molecules. We find that each of the studied species should be better represented as a resonance hybrid of three leading resonance structures, namely, H-Ng(+ -):Y (I), H:(- +)Ng-Y (II), and H^Y (III), in which the "ω-bonded" structures I and II arise from the complementary donor-acceptor interactions nY → σ*HNg and nH → σ*NgY, while the "long-bond" ([small sigma, Greek, circumflex]-type) structure III arises from the nNg → [small sigma, Greek, circumflex]*HY/[small sigma, Greek, circumflex]HY interaction. The bonding for all of the studied molecules can be well described in terms of the continuously variable resonance weightings of 3c/4e ω-bonding and [small sigma, Greek, circumflex]-type long-bonding motifs. Furthermore, we find that the calculated bond orders satisfy a generalized form of "conservation of bond order" that incorporates both ω-bonding and long-bonding contributions [viz., (bHNg + bNgY) + bHY = bω-bonding + blong-bonding = 1]. Such "conservation" throughout the title series implies a competitive relationship between ω-bonding and [small sigma, Greek, circumflex]-type long-bonding, whose variations are found to depend in a chemically reasonable manner on the electronegativity of Y and the outer valence-shell character of the central Ng atom. The calculated bond orders are also found to exhibit chemically reasonable correlations with bond lengths, vibrational frequencies, and bond dissociation energies, in accord with Badger's rule and related empirical relationships. Overall, the results provide electronic principles and chemical insight that may prove useful in the rational design of noble-gas hydrides of

  8. Dynamic and static behavior of hydrogen bonds of the X-H···π type (X = F, Cl, Br, I, RO and RR'N; R, R' = H or Me) in the benzene π-system, elucidated by QTAIM dual functional analysis.

    Science.gov (United States)

    Sugibayashi, Yuji; Hayashi, Satoko; Nakanishi, Waro

    2015-11-21

    Dynamic and static behavior of the X-H-*-π interactions in X-H-*-π(C6H6) (X = F, Cl, Br, I, HO, MeO, H2N, MeHN and Me2N) is elucidated by QTAIM-DFA (QTAIM dual functional analysis), which we proposed recently, as the first step to clarify various types of X-H-*-π interactions. The asterisk * emphasizes the existence of the bond critical point (BCP) on the interaction in question. Total electron energy densities (H(b)(r(c))) are plotted versus H(b)(r(c)) - V(b)(r(c))/2 [=(ℏ(2)/8m)∇(2)ρ(b)(r(c))] at BCPs in QTAIM-DFA, where V(b)(r(c)) are potential energy densities at BCPs. In our treatment, data for the perturbed structures around the fully optimized ones are employed, in addition to those for the fully optimized structures. Data from the fully optimized structures are analyzed by the polar coordinate (R, θ) representation. Each plot for an interaction, containing data from the perturbed structures, shows a specific curve, which provides important information. The plot is expressed by (θ(p), κ(p)): θ(p) corresponds to the tangent line of the plot and κ(p) is the curvature. θ and θ(p) are measured from the y-axis and the y-direction, respectively. While (R, θ) correspond to the static nature, (θ(p), κ(p)) represent the dynamic nature of interactions. The nature of the X-H-*-π(C6H6) interactions is well specified by (R, θ) and (θ(p), κ(p)). All interactions, examined in this work, are classified by the pure closed shell interactions and predicted to have the van der Waals nature.

  9. 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.

  10. Synthesis and photoluminescence properties of an unprecedented phosphinine-Cu4Br4 cluster

    NARCIS (Netherlands)

    Roesch, Philipp; Nitsch, Jörn; Lutz, Martin; Wiecko, Jelena; Steffen, Andreas; Müller, Christian

    2014-01-01

    A hitherto unprecedented polynuclear phosphinine-Cu(I) complex has been prepared and crystallographically characterized. The molecular structure in the crystal verifies the presence of the heterocubanetype tetrameric cluster [LCuBr]4 (L = 2,4-diphenyl-5-methyl-6-(2,3- dimethylphenyl)phosphinine),

  11. Synthesis and photoluminescence properties of an unprecedented phosphinine-Cu4Br4 cluster

    NARCIS (Netherlands)

    Roesch, Philipp; Nitsch, Jörn; Lutz, Martin|info:eu-repo/dai/nl/304828971; Wiecko, Jelena; Steffen, Andreas; Müller, Christian

    2014-01-01

    A hitherto unprecedented polynuclear phosphinine-Cu(I) complex has been prepared and crystallographically characterized. The molecular structure in the crystal verifies the presence of the heterocubanetype tetrameric cluster [LCuBr]4 (L = 2,4-diphenyl-5-methyl-6-(2,3- dimethylphenyl)phosphinine), wh

  12. Comprehensive proteome quantification reveals NgBR as a new regulator for Epithelial-Mesenchymal Transition of breast tumor cells

    OpenAIRE

    Zhao, Baofeng; Xu, Bo; Hu, Wenquan; Song, Chunxia; Wang, Fangjun; Liu, Zhong; Ye, Mingliang; Zou, Hanfa; Miao, Qing R.

    2014-01-01

    Nogo-B receptor (NgBR) is a type I receptor and specifically binds to ligand Nogo-B. Our previous work has shown that NgBR is highly expressed in human breast invasive ductal carcinoma. Here, comprehensive proteome quantification was performed to examine the alteration of protein expression profile in MDA-MB-231 breast tumor cells after knocking down NgBR using lentivirus-mediated shRNA approach. Among a total of 1771 proteins feasibly quantified, 994 proteins were quantified in two biologica...

  13. An Empirical Approach to Determining the Boundary Layer Bromine Monoxide (BrO) Abundance from Satellite Total Column Measurements

    Science.gov (United States)

    Simpson, W. R.; Donohoue, D.; Carlson, D. A.

    2009-12-01

    Unique chemistry in the Arctic boundary layer during springtime liberates bromine from sea salt, producing reactive halogen gases (e.g. atomic bromine and bromine monoxide radicals) that then drastically alter atmospheric oxidation pathways. This phenomenon causes ozone depletion events and affects mercury deposition to the snowpack. Satellite remote sensing (e.g. OMI and GOME2 observations) techniques can detect the total column abundance of BrO, which is generally the primary species of the reactive bromine family. However, BrO is also present in the stratosphere, so it is necessary to partition the satellite-observed BrO column abundance into boundary layer and non-boundary layer (primarily stratospheric) partial columns to be able to infer boundary layer abundances and hence chemical affects near the Earth's surface (i.e. ozone and mercury impacts). In this presentation, we describe an empirical method for partitioning the BrO total column and apply it globally during spring 2008. The method indicates that some BrO total column enhancements ("hotspots") are not actually enhancements in the boundary layer BrO abundance but occur aloft. Movies and a statistical analysis of the inferred boundary layer BrO abundance are presented. The method has been tested and performs well at the Barrow field site. However, in areas that lack routine ground truth BrO measurements (e.g. Hudson Bay, Canada), large tropospheric BrO abundances are indicated. It is not clear if these inferred boundary layer BrO events are real or if the simple empirical method described here is failing in those locations. Verification of this method over large spatial regions of the Arctic is needed.

  14. Holographic Properties of BR-D96N Film and Its Application in Hologram Aberration Correction

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yuan(郑媛); YAO Bao-Li(姚保利); WANG Ying-Li(王英利); MENKE Neimule(门克内木乐); LEI Ming(雷铭); CHEN Guo-Fu(陈国夫); Norbert HAMPP

    2003-01-01

    A biophotochromic material, i.e., genetic mutant bacteriorhodopsin (BR-D96N), was experimentally studied on its holographic recording properties. The saturation absorption curve and the diffraction efficiency curve were measured respectively. As holographic storage application, reflection type polarization holograms were recorded on the BR-D96N film. The 173° configuration between the object and reference beams proves that the spatial resolution of the film is over 6000 lines/mm. By using phase conjugate wave of reference beam as reconstruction beam, the distorted object image introduced by the optical components and the defects in the recording medium can be well corrected.

  15. 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.

  16. On the Reaction Mechanism of Br2 with OCS

    Institute of Scientific and Technical Information of China (English)

    Hai Tao YU; Hua ZHONG; Ming Xia LI; Hong Gang FU; Jia Zhong SUN

    2005-01-01

    The reaction mechanism of photochemical reaction between Br2 ( 1 ∑ ) and OCS ( 1 ∑ ) is predicted by means of theoretical methods. The calculated results indicate that the direct addition of Br2 to the CS bond of OCS molecule is more favorable in energy than the direct addition of Br2to the CO bond. Furthermore, the intermediate isomer syn-BrC(O)SBr is more stable thermodynamically and kinetically than anti-BrC(O)SBr. The original resultant anti-BrC(O)SBr formed in the most favorable reaction channel can easily isomerize into the final product syn-BrC(O)SBr with only 31.72 kJ/mol reaction barrier height. The suggested mechanism is in good agreement with previous experimental study.

  17. Reaction mechanism and structure-reactivity relationships in the stereospecific 1,4-polymerization of butadiene catalyzed by neutral dimeric allylnickel(II) halides [Ni(C3H5)X]2 (X- = Cl-, Br-, I-): a comprehensive density functional theory study.

    Science.gov (United States)

    Tobisch, S; Taube, R

    2001-09-03

    For the first time, a comprehensive and consistent picture of the catalytic cycle of 1,4-polymerization of butadiene with neutral dimeric allylnickel(II) halides [Ni(C3H5)X]2 (X = Cl- (I), Br- (II), and I- (III)) as single-site catalysts has been derived by means of quantum chemical calculations that employ a gradient-corrected density-functional method. All crucial reaction steps of the entire catalytic course have been scrutinized, taking into account butadiene pi complex formation, symmetrical and asymmetrical splitting of dimeric pi complexes, cis-butadiene insertion, and anti-syn isomerization. The present investigation examines, in terms of located structures, energies and activation barriers, the participation of postulated intermediates, in particular it aimed to clarify whether monomeric or dimeric species are the catalytically active species. Prior qualitative mechanistic assumptions are substituted by the presented theoretically well-founded and detailed analysis of both the thermodynamic and the kinetic aspects, that substantially improve the insight into the reaction course and enlarge them with novel mechanistic proposals. From a mechanistic point of view, all three catalysts exhibit common characteristics. First, chain propagation occurs by cis-butadiene insertion into the pi-butenylnickel(II) bond with nearly identical intrinsic free-energy activation barriers. Second, the reactivity of syn-butenyl forms is distinctly higher than that of anti forms. Third, the chain-propagation step is rate-determining in the entire polymerization process, and the pre-established anti-syn equilibrium can always be regarded as attained. Accordingly, neutral dimeric allylnickel(II) halides catalyze the formation of a stereo-regular trans-1,4-polymer under kinetic control following the k1t channel with butenyl(halide)(butadiene)NiII complexes being the catalytically active species. Production of a stereoregular cis-1,4-polymer with allylnickel chloride can only be

  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. 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.

  20. 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...

  1. 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...

  2. Multi-Agent-System till brädspel

    OpenAIRE

    Wahlström, Marco; Karlsson, Jonas

    2012-01-01

    För att ta reda på hur väl en Multi-Agent-Systems-bot kan stå sig mot andra, icke-MAS-bottar, så har vi implementerat en bot till brädspelet Arimaa. Botten är implementerad i C++ och den kan spela mot andra bottar, eller människor, genom Arimaas officiella hemsida. Syftet har varit att skapa en fullfjädrad bot som både klarar av att spela korrekt, och att spela bra. För att ta reda på om MAS är en bra designfilosofi för Arimaa så har vi utmanat ett antal av de bottar som andra människor skapa...

  3. <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

  4. Anticorrosion Performance of Carbon Steel in 55% LiBr Solution Containing PMA/SbBr3 Inhibitor

    Institute of Scientific and Technical Information of China (English)

    HU Xian-qi; LIANG Cheng-hao; HUANG Nai-bao

    2006-01-01

    The anticorrosion performance of carbon steel in 55% LiBr solution containing PMA/SbBr3 inhibitor was studied by weight-loss tests, electrochemical measurements and surface analysis. In 55%LiBr+PMA/SbBr3 solution, corrosion rates of carbon steel at 145 ℃, 175 ℃, 190 ℃ and 240 ℃ are 18.32 μm·a-1, 27.68 μm·a-1, 53.58 μm·a-1 and 73.78 μm·a-1, respectively. PMA/SbBr3 inhibitor may inhibit the corrosion of carbon steel in 55% LiBr solution effectively. Especially, it shows an excellent corrosion inhibition performance at high temperature. Both anodic and cathodic reactions of carbon steel may be inhibited by PMA/SbBr3 inhibitor, so it may be classified as mixed inhibitor. In 55%LiBr+PMA/SbBr3 solution, the apparent activation energy of the corrosion reaction of carbon steel is 29.61 kJ·mol-1. The corrosion inhibition mechanism of PMA/SbBr3 is suggested as follows: PMA has the effect of inhibiting hydrogen evolution and a strong oxidizing property; Sb3+ also exhibits oxidizing properties, and can exist stably with PMA in LiBr solutions; the passive film comprising Fe2O3 and antimony formed on carbon steel surface may prevent Br- from diffusing into the metal surface due to the synergistic effect of PMA and Sb3+; As a result, the anticorrosion performance of carbon steel may be improved by PMA/SbBr3 inhibitor in 55% LiBr solution.

  5. Ozone Depletion Potential of CH3Br. Appendix H

    Science.gov (United States)

    Ko, Malcolm K. W.; Sze, Nien Dak; Scott, Courtney; Rodriguez, Jose M.; Weisenstein, Debra K.; Sander, Stanley P.

    1998-01-01

    The ozone depletion potential (ODP) of methyl bromide (CH3Br) can be determined by combining the model-calculated bromine efficiency factor (BEF) for CH3Br and its atmospheric lifetime. This paper examines how changes in several key kinetic data affect BEF. The key reactions highlighted in this study include the reaction of BrO + HO2, the absorption cross section of HOBr, the absorption cross section and the photolysis products of BrONO2, and the heterogeneous conversion of BrONO2 to HOBr and HNO3 on aerosol particles. By combining the calculated BEF with the latest estimate of 0.7 year for the atmospheric lifetime of CH3Br, the likely value of ODP for CH3Br is 0.39. The model-calculated concentration of HBr (approx. 0.3 pptv) in the lower stratosphere is substantially smaller than the reported measured value of about 1 pptv. Recent publications suggested models can reproduce the measured value if one assumes a yield for HBr from the reaction of BrO + OH or from the reaction of BrO + HO2. Although the evaluation concluded any substantial yield of HBr from BrO + HO2 is unlikely, for completeness, we calculate the effects of these assumed yields on BEF for CH3Br. Our calculations show that the effects are minimal: practically no impact for an assumed 1.3% yield of HBr from BrO + OH and 10% smaller for an assumed 0.6% yield from BrO + HO2.

  6. Türgi valmistus solvunult Brüsselile selga keerama / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2005-01-01

    Kreeka otsustas toetada Türgi liitumist EL-iga, samal ajal kui Austria nõudis liitumiskõneluste tingimuste karmistamist. Türgi pealinnas toimus meeleavaldus EL-i vastu, 54 % türklastest ootas valitsuse lahkumist Brüsselis toimuvatelt kõnelustelt, 72% keeldus pidamast genotsiidiks armeenlaste kohtlemist I maailmasõja ajal. 60% türklastest on siiski EL-iga liitumise poolt

  7. Türgi valmistus solvunult Brüsselile selga keerama / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2005-01-01

    Kreeka otsustas toetada Türgi liitumist EL-iga, samal ajal kui Austria nõudis liitumiskõneluste tingimuste karmistamist. Türgi pealinnas toimus meeleavaldus EL-i vastu, 54 % türklastest ootas valitsuse lahkumist Brüsselis toimuvatelt kõnelustelt, 72% keeldus pidamast genotsiidiks armeenlaste kohtlemist I maailmasõja ajal. 60% türklastest on siiski EL-iga liitumise poolt

  8. 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

  9. <i>Festuca paniculatai> (L. Schinz & Thell. subsp. paui, nuevo taxon para la Península Ibérica

    Directory of Open Access Journals (Sweden)

    Cebolla, Consuelo

    1990-05-01

    Full Text Available A new subspecies, <i>Festuca paniculatai> (L. Schinz & Thell. subsp. <i>paui> Cebolla & Rivas Ponce (Poaceae is described.<br>>Se describe una subespecie nueva, <i>Festuca paniculatai> (L. Schinz & Thell. subsp. <i>paui> Cebolla & Rivas Ponce (Poaceae.

  10. Kinetic studies on the temperature dependence of the BrO + BrO reaction using laser flash photolysis.

    Science.gov (United States)

    Ferracci, Valerio; Hino, Kaori; Rowley, David M

    2011-05-07

    The BrO self-reaction, BrO + BrO → products (1), has been studied using laser flash photolysis coupled with UV absorption spectroscopy over the temperature range T = 266.5-321.6 K, under atmospheric pressure. BrO radicals were generated via laser photolysis of Br(2) in the presence of excess ozone. Both BrO and O(3) were monitored via UV absorption spectroscopy using charge-coupled device (CCD) detection. Simultaneous fitting to both temporal concentration traces allowed determination of the rate constant of the two channels of , BrO + BrO → 2Br + O(2) (1a); BrO + BrO → Br(2) + O(2) (1b), hence the calculation of the overall rate of and the branching ratio, α: k(1a)/cm(3) molecule(-1) s(-1) = (1.92 ± 1.54) × 10(-12) exp[(126 ± 214)/T], k(1b)/cm(3) molecule(-1) s(-1) = (3.4 ± 0.8) × 10(-13) exp[(181 ± 70)/T], k(1)/cm(3) molecule(-1) s(-1) = (2.3 ± 1.5) × 10(-12) exp(134 ± 185 /T) and α = k(1a)/k(1) = (0.84 ± 0.09) exp[(-7 ± 32)/T]. Errors are 1σ, statistical only. Results from this work show a weaker temperature dependence of the branching ratio for channel (1a) than that found in previous work, leading to values of α at temperatures typical of the Polar Boundary Layer higher than those reported by previous studies. This implies a shift of the partitioning between the two channels of the BrO self-reaction towards the bromine atom and hence directly ozone-depleting channel (1a). This journal is © the Owner Societies 2011

  11. 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

  12. 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

  13. Radiation effects on bipolar junction transistors and integrated circuits produced by different energy Br ions

    Science.gov (United States)

    Li, Xingji; Geng, Hongbin; Liu, Chaoming; Zhao, Zhiming; Lan, Mujie; Yang, Dezhuang; He, Shiyu

    2009-12-01

    The radiation responses of the NPN bipolar junction transistors (BJTs) and the TTL bipolar integrated circuits (ICs) have been examined using 20, 40 and 60 MeV Br ions. Key electric parameter was measured and compared after each energy irradiation. Experimental results demonstrate that the degradation in electric parameters caused by the Br ions shows a common feature for the NPN BJTs and TTL ICs, in which the degradation is strengthened with decreasing the Br ions energy. The ionizing dose ( D i) and displacement dose ( D d) as a function of the chip depth in the bipolar devices were calculated using the SRIM code, in order to analyze the radiation effects on the NPN BJTs and the Bipolar ICs. From the experiment and calculation results, it could be deduced that the Br ions mainly cause displacement damage to both the NPN BJTs and the TTL ICs, and the higher the ratio of D d/( D d+D i), the larger the degradation in electric parameters at a given total dose.

  14. Synthesis and Crystal Structure of [Ca(DMF)6][Mo6Br8Cl6

    Institute of Scientific and Technical Information of China (English)

    LIU Xi; CAI Li-Zhen; GUO Guo-Cong; LI Qiang; HUANG Jin-Shun

    2006-01-01

    The reaction of MoBr2 with CaCl2 in DMF (N, N'-dimethylformamide) gives the cluster complex [Ca(DMF)6][Mo6Br8Cl6] 1 by using standard Schlenk techniques. This cluster complex crystallizes in triclinic, space group (P1) with a = 10.329(4), b = 10.349(4), c = 12.510(5) (A), α = 103.793(5), β = 98.562(3), γ = 98.268(5)°, V = 1261.5(9)(A)3, Dc = 2.509 g/cm3, Z = 1, C18H42Br8CaCl6Mo6N6O6, Mr = 1906.28, μ = 8.236 mm-1, λ(MoKα) = 0.71073(A)and F(000) = 894. The final R = 0.0589 and wR = 0.1458 for 2759 observed reflections with I > 2σ(I). The structure is composed of isolated octahedral coordination cations and discrete cluster anions, and these two kinds of ions connect each other to form a 3-D framework with similar packing patterns as CsCl through weak C-H…X (X = Br, Cl) hydrogen bonds.

  15. Alocação de linhagens de milho derivadas das populações BR-105 e BR-106 em grupos heteróticos Allocation of maize lines from BR-105 and BR-106 populations to heterotic groups

    Directory of Open Access Journals (Sweden)

    Rogério de Melo Costa Pinto

    2001-09-01

    Full Text Available Os grupos heteróticos são importantes no melhoramento de milho, pois permitem o uso mais eficiente do germoplasma. Assim, o objetivo deste trabalho foi alocar linhagens de milho em grupos heteróticos a partir de estimativas da capacidade específica de combinação. Oito linhagens S3 da população BR-105 e dez da BR-106, foram cruzadas ao nível interpopulacional seguindo um sistema dialélico. Oitenta híbridos simples foram obtidos e avaliados em látices em três ambientes. Foram avaliados os caracteres produção de grãos (PG, altura da planta (AP e altura da espiga (AE. As estimativas das capacidades geral (CGC e específica (CEC de combinação foram obtidas segundo o método 4, modelo I de Griffing. A partir das estimativas de CEC, as linhagens foram alocadas aos respectivos grupos heteróticos utilizando-se o método UPGMA (média aritmética não ponderada para a construção do dendrograma e a dispersão gráfica pelo método das coordenadas principais. Para PG, as linhagens foram alocadas em quatro grupos heteróticos, sendo dois grupos em cada população. Para AP e AE, o uso das estimativas de CEC não foi eficiente para alocar as linhagens em grupos heteróticos. As análises de agrupamento e de coordenadas principais foram eficientes na alocação das linhagens em grupos heteróticos para PG. Então, como a produção de grãos é a principal característica para o melhoramento de milho, com a alocação das linhagens em quatro grupos heteróticos, os cruzamentos serão direcionados e o processo de melhoramento se tornará mais eficiente, evitando a obtenção e a avaliação de cruzamentos (híbridos desnecessários.The heterotic groups are important in maize breeding programs because they allow the most efficient use of the germoplasm. The objective of this research was to allocate maize lines to heterotic groups from estimates of specific combining ability (SCA. Eight and ten S3 lines derived from populations BR-105 and BR

  16. 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.

  17. 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.

  18. Investigation of BrO in volcanic plumes: Comparing satellite data from OMI and GOME-2

    Science.gov (United States)

    Warnach, Simon; Hörmann, Christoph; Sihler, Holger; Bobrowski, Nicole; Beirle, Steffen; Penning de Vries, Marloes; Dinger, Florian; Platt, Ulrich; Wagner, Thomas

    2017-04-01

    It has been repeatedly shown in the past by measurements from the ground and from space that volcanic plumes contain widely varying amounts of bromine monoxide (BrO). The relative amount of BrO in a volcanic plume, i. e. with respect to sulphur dioxide (SO2), is mainly affected by degassing composition as well as chemical processes, but the reasons for the variation is still not fully understood. Our study aims at obtaining a better understanding of bromine emissions from volcanoes. The high spatial resolution of current satellite instruments such as OMI (13x24 km2) and GOME-2 (40x80 km2), and particularly that of future instruments like TROPOMI (3.5x7 km2) allows to resolve the volcanic plume of eruptive events and makes. The combination of the high spatial resolution and the global coverage of satellite instruments make it possible to study the spatial variability of trace gases in a large number of volcanic plumes from a large number of volcanoes. In this study, we investigate the BrO and SO2 distribution as well as the BrO/SO2 ratio within volcanic plumes observed by OMI since 2007. We apply a plume detection algorithm which uses the retrieved SO2 column for plume identification. These data obtained from OMI measurements are compared to plumes identified from GOME-2 data. Differences in the number of identified plumes and the degree of agreement regarding the retrieved spatial distribution of BrO and SO2, as well as the calculated BrO/SO2 ratio between plumes observed by both instruments, are discussed. Differences are mainly attributed to the differences between the two instruments with respect to spatial resolution and overpass time (GOME-2 at 9:30, OMI at 13:30 local time).

  19. 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; . ..

  20. I principali aspetti biologici del volo spaziale, con particolare riguardo al microclima della cabina

    Directory of Open Access Journals (Sweden)

    A. SCANO

    1963-06-01

    Full Text Available Dopo un cenno ai principali aspetti biologici del volo<br />spaziale e dopo aver delineato alcune limitazioni a t t u a l i di questo, l'A. espone<br />brevemente, sulla scorta delle ricerche eseguite e delle ipotesi presentate<br />da vari studiosi, le conoscenze sui più importanti problemi dell'ambiente<br />di una cabina spaziale occupata dall'uomo.<br />Vengono esaminati criticamente il rifornimento di 02 e l'eliminazione<br />di C02, l'eliminazione del vapor d'acqua e delle altre sostanze gassose o<br />volatili prodotte dall'uomo o dalle apparecchiature della cabina, l'eliminazione<br />ed il ricupero parziale o totale degli escreti, il mantenimento della<br />pressione e della composizione dell'aria o della miscela respirata, il mantenimento<br />della temperatura.<br />Particolare considerazione viene data ai sistemi chiusi di rigenerazione<br />dei gas respiratori, dei quali vengono discussi i diversi tipi in base allo s t a to<br />a t t u a l e dei risultati sperimentali, alla possibilità di pratica attuazione, alla<br />sicurezza ed al rendimento assoluto e relativo al tempo di impiego.<br />Si concludo che per viaggi di qualche giorno sono ancora preferibili le<br />scorte di <>2 e la fissazione chimica o fisica del C02 e degli altri inquinanti,<br />per viaggi di maggior durata (settimane e mesi appaiono attualmente migliori<br />i cicli chiusi di rigenerazione chimica e fisico-chimica dell'02 dal C02<br />espirato e dall'acqua di ricupero, mentre i cicli chiusi di rigenerazione biologica<br />— peraltro interessanti perchè atti a risolvere vari problemi contemporaneamente<br />presentano ancora notevoli incognite.

  1. 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>.

  2. Growth, structure and optical properties of Tl{sub 4}HgBr{sub 6} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Khyzhun, O.Y., E-mail: khyzhun@ipms.kiev.ua [Frantsevych Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, 3 Krzhyzhanivsky Street, 03142 Kyiv (Ukraine); Kityk, I.V. [Electrical Engineering Department, Częstochowa University of Technology, Armii Krajowej 17, PL-42-217 Częstochowa (Poland); Piasecki, M. [Institute of Physics, J. Dlugosz University Częstochowa, Armii Krajowej 13/15, Częstochowa (Poland); Fedorchuk, A.O. [Department of Inorganic and Organic Chemistry, Lviv National University of Veterinary Medicine and Biotechnologies, 50 Pekarska Street, 79010 Lviv (Ukraine); Levkovets, S.I. [Department of Inorganic and Physical Chemistry, Eastern European National University, 13 Voli Avenue, 43025 Lutsk (Ukraine); Fochuk, P.M. [Yuriy Fed’kovych Chernivtsi National University, 2 Kotziubynskoho Street, 58012 Chernivtsi (Ukraine); Myronchuk, G.L. [Department of Solid State Physics, Lesya Ukrainka Eastern European National University, 13 Voli Avenue, 43025 Lutsk (Ukraine); Parasyuk, O.V. [Department of Inorganic and Physical Chemistry, Eastern European National University, 13 Voli Avenue, 43025 Lutsk (Ukraine)

    2015-12-15

    Tl{sub 4}HgBr{sub 6} single crystals were grown using solution-fusion method. The crystal structure of the ternary bromide was refined. Tl{sub 4}HgBr{sub 6} crystallizes in the non-centrosymmetric space group P4nc with the lattice parameters a=8.9539(8) Å and c=8.7884(8) Å and it is isostructural to the Tl{sub 4}HgI{sub 6} compound. The non-centrosymmetric structure of the Tl{sub 4}HgBr{sub 6} compound was also confirmed by the existence of a modest second harmonic generation effect (0.4–0.5 pm/V) and by the value of piezoelectric coefficient (0.9 pm/V). The electronic structure of Tl{sub 4}HgBr{sub 6} was explored using X-ray photoelectron spectroscopy (XPS) and X-ray emission spectroscopy (XES). In particular, for the Tl{sub 4}HgBr{sub 6} crystal, we have measured XPS core-level and valence-band spectra for both pristine and Ar{sup +} ion-bombarded surfaces. The XPS data reveal low hygroscopicity of Tl{sub 4}HgBr{sub 6}, the property that is very important when handling this material in optoelectronic devices working at ambient conditions. The present XPS data indicate that the Tl{sub 4}HgBr{sub 6} single crystal surface is rather sensitive with respect to Ar{sup +} ion-bombardment: such a treatment reduces significantly mercury content in the topmost surface layers. Comparison on a common energy scale of the XPS valence-band spectrum of Tl{sub 4}HgBr{sub 6} and the XE Br Kβ{sub 2} band, representing peculiarities of the energy distribution of the Br 4 p states, reveals that the main contribution of the valence Br p states occurs in the upper portion of the valence band, with also their significant contributions in other valence band regions. The measurements of spectral distribution of the absorption coefficient indicate that the Tl{sub 4}HgBr{sub 6} compound is a semiconductor with the bandgap energy value of 2.43 eV at 300 K, and the bandgap energy increases up to 2.48 eV when temperature decreases to 100 K.

  3. Forsvarets opgaver i Arktis

    DEFF Research Database (Denmark)

    Nielsen, Thomas Galasz

    at accelerere den økonomiske aktivitet i Arktis bl.a. ved øget udvinding af mineraler og fossile brændstoffer, fiskeri samt turisme. Det kan betyde en stigende skibstrafik i de arktiske egne, ligesom nordlige skibsruter fra Europa og Nordamerika til Asien i tiltagende omfang vil være åbne for kommerciel...

  4. Forsvarets opgaver i Arktis

    DEFF Research Database (Denmark)

    Nielsen, Thomas Galasz

    at accelerere den økonomiske aktivitet i Arktis bl.a. ved øget udvinding af mineraler og fossile brændstoffer, fiskeri samt turisme. Det kan betyde en stigende skibstrafik i de arktiske egne, ligesom nordlige skibsruter fra Europa og Nordamerika til Asien i tiltagende omfang vil være åbne for kommerciel...

  5. CsEuBr3: Crystal structure and its role in the photostimulation of CsBr :Eu2+

    Science.gov (United States)

    Hesse, S.; Zimmermann, J.; von Seggern, H.; Ehrenberg, H.; Fuess, H.; Fasel, C.; Riedel, R.

    2006-10-01

    CsBr :Eu2+ has recently been investigated as a photostimulable x-ray storage phosphor with great potential for application in high-resolution image plates. In a recent paper Hackenschmied et al. [J. Appl. Phys. 93, 5109 (2003)] suggested that segregations of CsEuBr3 or Cs4EuBr6 formed within CsBr :Eu2+ during annealing are responsible for an increase in the photostimulated luminescence (PSL) yield. In this work single crystals of CsEuBr3 were prepared by a one step synthesis and identified by x-ray diffraction (XRD) analysis as single phase perovskites. It was concluded that, after preparation, CsEuBr3 degrades in normal atmosphere into at least two phases, one of which is the orthorhombic structure of Cs2EuBr5•10H2O. The XRD powder diffraction pattern of this compound is very similar to that of the segregations observed within CsBr :Eu2+ and reported by Hackenschmied et al. However, the increased PSL yield in CsBr :Eu2+ after annealing cannot be due to the segregations, because the trivalent nature of the europium in the segregations renders them PSL inactive.

  6. Gli effetti della subgravità e i metodi per riprodurla a terra e in volo

    Directory of Open Access Journals (Sweden)

    G. MEINERI

    1963-06-01

    Full Text Available L'A. enuncia brevemente il problema della subgravità<br />descrivendo le principali soluzioni sperimentali escogitate nel corso dell'ultimo<br />decennio per rispondere ai vari interrogativi cbe tale particolare caratteristica<br />del volo spaziale, clie non trova riscontro in alcuna altra condizione nota<br />all'uomo, pone agli studiosi, biologi e tecnici.<br />L'A. passa quindi a descrivere i principali metodi e dispositivi per<br />riprodurre lo stato di subgravità, distinguendo i sistemi « a terra », auspicabili<br />per la loro agevolezza, sicurezza, ma cbe in genere non riproducono che<br />taluni aspetti fisiopsicologici dello stato subgravitazionale, dai sistemi, ben<br />più indaginosi, che consentono di realizzare stati di subgravità reali e completi<br />(voli parabolici, lanci suborbitali e orbitali di missili. Passa infine a<br />esporre quanto è stato fatto in questo campo presso il Centro di Studi e<br />Ricerche di Medicina Aeronautica e Spaziale di Roma, impiegando la « Torre<br />di Subgravità », ideata e costruita presso detto Centro, la quale consente<br />di realizzare veri stati di subgravità, sia pure di breve durata, preceduti e<br />seguiti da accelerazioni. La « Torre di Subgravità » ha permesso di affrontare<br />alcuni problemi inerenti al volo spaziale, soprattutto quelli jtosti dagli stati<br />di transizione tra le fasi attive e quella passiva del volo, proponendo soluzioni<br />di non trascurabile interesse pratico (comportamento psicomotorio dei<br />soggetti, ruolo del labirinto in toto e delle sue singole componenti, ecc..<br />L'A. conclude quindi facendo rilevare l'interesse di questa metodica,<br />suscettibile di sviluppi anche più ampi, che può ben allinearsi nel campo<br />mondiale alle ricerche inerenti al volo spaziale.

  7. PRR performance of Cu- and CuBr-vapor lasers

    Science.gov (United States)

    Fedorov, V. F.; Evtushenko, Gennadiy S.; Klimkin, Vladimir M.; Polunin, Yu. P.; Soldatov, Anatoly N.; Sukhanov, Viktor B.

    1998-06-01

    Results obtained from comparative analysis of the pulse repetition rate performance of Cu- and CuBr-vapor lasers operated at high pump pulse repetitions (approximately 100 kHz) are reported. For a CuBr laser with a 8 mm diameter discharge tube the laser pulse repetition rate as high as 270 kHz was realized.

  8. [Br-76]bromodeoxyuridine PET in tumor-bearing animals

    NARCIS (Netherlands)

    Gardelle, O; Roelcke, U; Vontobel, P; Crompton, NEA; Guenther, [No Value; Blauenstein, P; Schubiger, AP; Blattmann, H; Ryser, JE; Leenders, KL; Kaser-Hotz, B

    2001-01-01

    5-bromodeoxyuridine (BUdR) provides in vitro measures of tumor cell proliferation. We used positron emission tomography to study tissue and plasma kinetics of [Br-76]BUdR in tumor-bearing animals. In order to account for the slow washout of the major plasma metabolite, [Br-76]bromide, a mathematical

  9. Nonadiabatic photofragmentation dynamics of BrCN{sup −}

    Energy Technology Data Exchange (ETDEWEB)

    Opoku-Agyeman, Bernice; McCoy, Anne B., E-mail: mccoy@chemistry.ohio-state.edu [Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210 (United States); Case, Amanda S.; Lehman, Julia H.; Lineberger, W. Carl, E-mail: wcl@jila.colorado.edu [JILA and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309 (United States)

    2014-08-28

    The photofragmentation dynamics of BrCN{sup −} in the 270–355 nm and the 430–600 nm wavelength regions is explored both experimentally and theoretically. In the case of excitation between 430 nm and 600 nm, it is found that the molecular ion accesses two dissociation channels with a measured 60:40 branching ratio that is nearly constant over this range of photon energies. The dominant product channel corresponds to Br{sup −} + CN, while the second channel correlates to spin-orbit excited Br{sup *} with CN{sup −}. A larger wavelength dependence of the branching ratio is observed at shorter wavelengths, where the fraction of Br{sup −} based products ranges from 80% to 95% at 355 nm and 270 nm, respectively. These branching ratios are reproduced and the mechanisms are explored by quantum dynamics calculations based on ground and excited state potential energy surfaces for BrCN{sup −}, evaluated at the SO-MRCISD level of theory. It is found that the electronic states that correlate to the two observed product channels are coupled through the spin-orbit terms in the electronic Hamiltonian. The strength of this coupling displays a strong dependence on the Br-CN angle. Specifically, after promotion to the excited state that is energetically accessible with 430–600 nm photons, it is found that when the wave packet accesses Br-CN separations of between 4 Å and 6 Å, predominantly the Br{sup −} + CN products are formed when the Br-CN angle is smaller than 120°. For larger values of the Br-CN angle, the Br{sup *} + CN{sup −} channel dominates. At the shorter wavelength excitation, the dynamics is complicated by a pair of states that correlate to electronically excited CN{sup *} + Br{sup −} products that borrow oscillator strength from the bright state, leading to an increase in the amount of Br{sup −} relative to CN{sup −}. The implications of these findings are discussed and compared to the experimentally measured product branching ratios for the

  10. Corrosion inhibition performance of a ionic liquid surfactant Br

    Directory of Open Access Journals (Sweden)

    Jing LIU

    2016-02-01

    Full Text Available In order to study the novel green organic mercury-substituting inhibitors, the ionic liquid surfactant 1-methyl-3-dodecyl imidazole bromide ( Br is synthesized with N-methyl imidazole and 1-bromodecane as raw materials. The corrosion inhibition of Br for zinc in zinc-manganese batteries is investigated using electrochemical methods and weight loss methods. The results show that corrosion inhibition efficiency increases with the increase of the concentration of Br, and when the concentration is higher than 8×10-3 mol/L, the inhibition efficiency tends to be stable. The polarization curve shows that Br belongs to mixed-type corrosion inhibitor. The thermodynamic parameters show that Br is spontaneously adsorbed on the zinc surface, forming a monomolecular adsorption layer, which fits with Langmuir adsorption isotherm with physical and chemical adsorption mechanism.

  11. Bränditutkimus - Case: Kalevala Koru Oy

    OpenAIRE

    Hartikainen, Marjo; Hyytiäinen, Jenni

    2012-01-01

    Tämä opinnäytetyö käsitteli Kalevala Koru Oy:n bränditutkimusta, missä tutkittiin Kalevala Korun merkitystä kuluttajille. Lisäksi selvitettiin, miten kuluttajien mielipiteet Kalevala Koru –brändistä ovat muuttuneet vuosien saatossa sekä miten nuoret kuluttajat kokevat Kalevala Korun brändinä. Aiheen valinta oli helppo, koska tutkittavaksi haluttiin tunnettu suomalainen brändi ja korut ovat myös lähellä tutkijoiden sydäntä. Tutkimus osoitti, että ihmisillä on hyvä tuntemus Kalevala Korusta brä...

  12. Effects of HtoH transitional nursing on the compliance of chemotherapy and quality of life among patients with liver cancer%医院到家庭连续护理对肝癌患者化疗依从性和生活质量的影响

    Institute of Scientific and Technical Information of China (English)

    郑文娟; 孙雯; 蒋贵兰

    2016-01-01

    Objective To explore the impacts of Hospital-to-Home( HtoH) transitional nursing on the compliance of chemotherapy and quality of lives among patients with liver cancer. Methods A total of 84 cases of liver cancer ( during the period between April 2012 and April 2014 ) were selected from multiple hospital of Zaozhuang and randomly divided into research group and control group, with each group 42 cases. The patients of control group was given the routine nursing care, while the patients of research group received 6 months continuous transitional nursing care that operated by medical staff members. The living quality of life score (QOL), self-rating depression scale (SDS) score, and level of compliance to chemotherapy were compared between two groups. Results The score of SDS in the research group was lower than score in the control group ( P<0. 05) except for the somatization disorder. The score of QOL in the research group was higher than that in the control group (P<0. 05). The level of compliance of chemotherapy in the research group was significantly better than than that in the control group (P<0. 05). Conclusions The HtoH transitional nursing can decrease patients′negative emotion, improve quality of life, and increase the compliance of chemotherapy.%目的 探讨医院到家庭(HtoH)连续护理对肝癌患者化疗依从性和生活质量的影响.方法 选取2012年4月—2014年4月枣庄市市立医院肿瘤中心84例肝癌患者作为研究对象,采用随机数字表法分为研究组和对照组,各42例,研究组实施由医院、社区医护人员协作的HtoH连续护理6个月,对照组实施临床常规护理,对比两组患者的生活质量指数(QOL)得分、抑郁自评量表(SDS)评分和化疗配合程度及依从性.结果 研究组SDS评分低于对照组,除躯体性障碍外,各项差异均有统计学意义(P<0.05).研究组QOL评分高于对照组,差异均有统计学意义(P<0.05);与对照组相比,研究组肝癌患者化疗

  13. Photochromic kinetic spectra and intermediates of BR-D96N

    Institute of Scientific and Technical Information of China (English)

    ZHENG; Yuan(郑媛); YAO; Baoli(姚保利); WANG; Yingli(王英利); LEI; Ming(雷铭); CHEN; Guofu(陈国夫); Norbert; Hampp

    2003-01-01

    BR-D96N is a kind of genetically site-specific mutant of bacteriorhodopsin (BR) with obvious photochromic effect. Compared to the wild type BR, the lifetime of M state of BR-D96N is prolonged to several minutes so that the photochromic kinetics and the intermediates formation can be studied by the conventional spectra analysis. In the experiment, the absorption spectra of the sample at different time after light illumination are measured with spectrophotometer. By fitting and analyzing the variation of the spectra, we suppose there are three main states in the photochromic process, i.e. B state (light-adapted state), M state and D state (dark-adapted state). The absorption spectra of the B state, M state and D state are extracted from the experimental data based on this three-state model and the spectra at various time are fitted with the least square method. So, the variations of population percentages of the M state, B state and D state are obtained and the M state and B state lifetimes are estimated. In another way, from measuring the absorption dynamics at 407 nm and 568 nm, the M state and B state lifetimes are also obtained by two exponential data fitting, which give coincident results with those of the spectra analysis.

  14. High-Resolution THz Measurements of BrO Generated in AN Inductively Coupled Plasma

    Science.gov (United States)

    Nemchick, Deacon J.; Drouin, Brian

    2017-06-01

    Building upon the foundation provided by previous work, the X_{1}^{2}Π_{3/2} and X_{2}^{2}Π_{1/2} states of the transient radical, BrO, were interrogated in previously unprobed spectral regions (0.5 to 1.7 THz) by employing JPL developed high-resolution cascaded frequency multiplier sources. Like other members of the halogen monoxides (XO), this species has been the target of several recent atmospheric remote sensing studies and is a known participant in a catalytic ozone degradation cycle. For the current work, BrO is generated in an inductively coupled plasma under dynamic flow conditions and rotational lines are observed directly at their Doppler-limited resolution. New spectral transitions including those owing to both the ground (ν=0) and excited (ν=1 and 2) vibrational states of isotopologues composed of permutations of natural abundance ^{16}O, ^{18}O, ^{79}Br, and ^{81}Br are fit to a global Hamiltonian containing both fine and hyperfine terms. In addition to further refining existing spectroscopic parameters, new observations will be made available to remote detection communities through addition to the JPL catalog. New findings will be discussed along with future plans to extend these studies to other halogen monoxides (X=Cl and I) and the more massive halogen dioxides (OXO & XOO).

  15. 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).

  16. 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

  17. 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.

  18. Studies on the acid-base properties of the ZnBr2NaBr molten salt system

    OpenAIRE

    1993-01-01

    The acid-base properties of the ZnBr2-NaBr melts at 623 K were investigated on the basis of the electromotive forcemeasurements of a zinc-zinc concentration cell. The following two chemical equilibria were postulated to describe theacid-base character of the melts.

  19. Reactive bromine chemistry in Mt. Etna's volcanic plume: the influence of total Br, high temperature processing, aerosol loading and plume-air mixing

    Directory of Open Access Journals (Sweden)

    T. J. Roberts

    2014-03-01

    Full Text Available Volcanic emissions present a source of reactive halogens to the troposphere, through rapid plume chemistry that converts the emitted HBr to more reactive forms such as BrO. The nature of this process is poorly quantified, yet is of interest to understand volcanic impacts on the troposphere, and infer volcanic activity from volcanic gas measurements (i.e. BrO / SO2 ratios. Recent observations from Etna report an initial increase and subsequent plateau or decline in BrO / SO2 ratios with distance downwind. We present daytime PlumeChem model simulations that reproduce and explain the reported trend in BrO / SO2 at Etna including the initial rise and subsequent plateau. Through suites of model simulations we also investigate the influences of volcanic aerosol loading, bromine emission, and plume-air mixing rate on the downwind plume chemistry. Emitted volcanic HBr is converted into reactive bromine by autocatalytic bromine chemistry cycles whose onset is accelerated by the model high-temperature initialisation. These rapid chemistry cycles also impact the reactive bromine speciation through inter-conversion of Br, Br2, BrO, BrONO2, BrCl, HOBr. Formation of BrNO2 is also discussed. We predict a new evolution of Br-speciation in the plume, with BrO, Br2, Br and HBr as the main plume species in the near downwind plume whilst BrO, and HOBr are present in significant quantities further downwind (where BrONO2 and BrCl also make up a minor fraction. The initial rise in BrO / SO2 occurs as ozone is entrained into the plume whose reaction with Br promotes net formation of BrO. Aerosol has a modest impact on BrO / SO2 near-downwind (2 occurs as entrainment of oxidants HO2 and NO2 promotes net formation of HOBr and BrONO2, whilst the plume dispersion dilutes volcanic aerosol so slows the heterogeneous loss rates of these species. A higher volcanic aerosol loading enhances BrO / SO2 in the (> 6 km downwind plume. Simulations assuming low/medium and high Etna

  20. Polar tropospheric BrO from GOME: timeseries and analysis of area covered by BrO 'clouds'

    Science.gov (United States)

    Hollwedel, J.; Beirle, S.; Frankenberg, C.; Grzegorski, M.; Khokhar, F.; Kühl, S.; Kraus, S.; Platt, U.; Wagner, T.; Wilms-Grabe, W.

    2003-04-01

    The GOME instrument aboard ERS-2 is measuring trace gases since 1995. With the DOAS method it is possible to extract vertical column densities of BrO (and other species) from the GOME spectra. The importance of BrO for the ozone depletion in the stratosphere is well known. BrO can also be liberated by heterogenous reactions on the surfaces of halogen rich aerosols, especially over the one year old sea ice. This mechanism is known as the Bromine explosion leading to the 'tropospheric ozone hole' in polar spring. Because of the global coverage and the long time series, comparisons of year-to-year variations are feasible. We focus especially on the comparison of the time and spatial variability of BrO events by analyzing time series and the extent of areas covered by BrO 'clouds'.

  1. Role of Rom protein in copy number control of plasmid pBR322 at different growth rates in Escherichia coli K-12

    DEFF Research Database (Denmark)

    Tove, Atlung; Christensen, Bjarke Bak; Hansen, Flemming G.

    1999-01-01

    The copy number per cell mass of plasmid pBR322 and a rom(-) derivative was measured as a function of generation time. In fast growing cells the copy number per cell mass was virtually identical for rom(+) and rom(-) derivatives. However, the copy number of pBR322 only increased 3- to 4-fold from...... a 20- to 80-min generation time, whereas the copy number of the torn derivative increased 7- to 10-fold. The copy number stayed constant for the rom(+) and rom(-) plasmids at generation times longer than 80-100 min. Thus, the presence of the rom gene decreased the copy number of plasmid pBR322...... effect on the copy number of pBR322 rom(-) at fast growth, but it decreased its copy number at slow growth to the same level as found for pBR322, i.e., complemented the pBR322 rom(-) plasmid. The pACYC184 plasmid and its rom(+) derivatives showed copy numbers similar to those of pBR322 rom(-) and pBR322...

  2. 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.

  3. Kinetics of BrO + NO → Br + NO{sub 2} Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Ree, Jongbaik [Chonnam National University, Gwangju (Korea, Republic of); Kim, Yoo Hang [Inha University, Incheon (Korea, Republic of); Shin, Hyung Kyu [Univ ersity of Nevada, Reno (United States)

    2016-03-15

    Quasiclassical trajectory procedures are used to study the kinetics of BrO + NO → Br + NO{sub 2} over the temperature range 225-450 K. Analytical forms of interaction potential functions including the contributions of electrostatic and induction effects are used. The rate constant varies weakly but negatively with temperature. It decreases from 1.96 X 10{sup -11} at 225 K to 1.06 X 10{sup -11} at 450 K, the results fitting closely the Arrhenius form k(T) = 6.15 X 10{sup -12} exp(253/T) cm{sup 3}/molecule/s. The rate constant at 300 K is 1.38 X 10{sup -11}. The electrostatic and induction effects contribute to the interaction of the reactants at large distance. These effects are dominated by charge-induced dipole interactions and lead to an increase of the kinetic energy of the relative motion, which is mainly responsible for the negative temperature dependence.

  4. 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.

  5. In situ measurements of BrO during AASE II

    Science.gov (United States)

    Avallone, L. M.; Toohey, D. W.; Schauffler, S. M.; Pollock, W. H.; Heidt, L. E.; Atlas, E. L.; Chan, K. R.

    1995-01-01

    BrO measured from the NASA ER-2 during Airborne Arctic Stratospheric Expedition (AASE) II exhibited a mean value (for 20-minute averages) of 5.4 +/- 0.3 pptv, with a standard deviation of 3.1 pptv. Ratios of BrO to available inorganic bromine (Br(sub y)) show only slight increases in polar regions relative to midlatitudes. A comparison between observed latitudinal and diurnal variations of this same ratio and that calculated by photochemical models shows reasonable agreement in behavior, but significant discrepancies in magnitude. It is unclear whether this difference is due to errors in measurements, models or both.

  6. On some questions of Fisk and Br\\"and\\'en

    CERN Document Server

    Yoshida, Rintaro

    2010-01-01

    P. Br\\"and\\'en recently proved a conjecture due to S. Fisk, R. P. Stanley, P. R. W. McNamara and B. E. Sagan. In addition, P. Br\\"and\\'en gave a partial answer to a question posed by S. Fisk regarding the distribution of zeros of polynomials under the action of certain non-linear operators. In this paper, we give an extension to a result of P. Br\\"and\\'en, and we also answer a question posed by S. Fisk.

  7. Four-Terminal Tandem Solar Cells Using CH3NH3PbBr3 by Spectrum Splitting.

    Science.gov (United States)

    Sheng, Rui; Ho-Baillie, Anita W Y; Huang, Shujuan; Keevers, Mark; Hao, Xiaojing; Jiang, Liangcong; Cheng, Yi-Bing; Green, Martin A

    2015-10-01

    In this work, the use of a high bandgap perovskite solar cell in a spectrum splitting system is demonstrated. A remarkable energy conversion efficiency of 23.4% is achieved when a CH3NH3PbBr3 solar cell is coupled with a 22.7% efficient silicon passivated emitter rear locally diffused solar cell. Relative enhancements of >10% are demonstrated by CH3NH3PbBr3/CH3NH3PbI3 and CH3NH3PbBr3/multicrystalline-screen-printed-Si spectral splitting systems with tandem efficiencies of 13.4% and 18.8%, respectively. The former is the first demonstration of an all perovskite split spectrum system. The CH3NH3PbBr3 cell on a mesoporous structure was fabricated by the vapor-assisted method while the planar CH3NH3PbI3 cell was fabricated by the gas-assisted method. This work demonstrates the advantage of the higher voltage output from the high bandgap CH3NH3PbBr3 cell and its suitability in a tandem system.

  8. Storme i rummet

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke

    2012-01-01

    Uvejr. Skaderne efter soludbruddet i 1859 begrænsede sig til elektriske stød og brændte papirer, mens tilsvarende skader i det moderne samfund ville beløbe sig til 5-10.000 milliarder kroner alene det første år. Derfor arbejder man nu med at kunne forudsige rum-uvejr....

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

    National Research Council Canada - National Science Library

    N. Theys; M. Van Roozendael; F. Hendrick; X. Yang; I. De Smedt; A. Richter; M. Begoin; Q. Errera; P. V. Johnston; K. Kreher; M. De Mazière

    2011-01-01

    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...

  10. Brûlure chez l’épileptique: brûlure pas comme les autres

    OpenAIRE

    Boukind, S.; O.K. Elatiqi; Dlimi, M.; D. Elamrani; Benchamkha, Y.; Ettalbi, S.

    2015-01-01

    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, son...

  11. 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

  12. Chiral Brønsted Acids for Asymmetric Organocatalysis

    Science.gov (United States)

    Kampen, Daniela; Reisinger, Corinna M.; List, Benjamin

    Chiral Brønsted acid catalysis is an emerging area of organocatalysis. Since the pioneering studies of the groups of Akiyama and Terada in 2004 on the use of chiral BINOL phosphates as powerful Brønsted acid catalysts in asymmetric Mannich-type reactions, numerous catalytic asymmetric transformations involving imine activation have been realized by means of this catalyst class, including among others Friedel-Crafts, Pictet-Spengler, Strecker, cycloaddition reactions, transfer hydrogenations, and reductive aminations. More recently, chiral BINOL phosphates found application in multicomponent and cascade reactions as for example in an asymmetric version of the Biginelli reaction. With the introduction of chiral BINOL-derived N-triflyl phosphoramides in 2006, asymmetric Brønsted acid catalysis is no longer restricted to reactive substrates. Also certain carbonyl compounds can be activated through these stronger Brønsted acid catalysts. In dealing with sensitive substrate classes, chiral dicarboxylic acids proved of particular value.

  13. 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

  14. 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

  15. Elu Brüsselis - teisem kui siin / Juune Holvandus

    Index Scriptorium Estoniae

    Holvandus, Juune

    2000-01-01

    Brüsseli kesklinnas elavast noorpaarist ja nende kodust. Veronique Mägi (isa eestlane) on tõlk. Ettevõtja Frederic Flamand on õppinud antiigindust. 1996. a. elati Eestis. Inimsuhetest Eestis ja Belgias. 11 ill.

  16. Some phytochemical studies or the genera <i>Aconitum> L., <i>Delphinium> L. and <i>Consolida> (DC. S.F. Gray

    Directory of Open Access Journals (Sweden)

    de la Fuente, Gabriel

    1990-12-01

    Full Text Available The diterpenoid alkaloids from <i>Aconitum napellusi> L. subsp. <i>castellanum> Molera & Blanché, <i>A. Burnatiii> Gayer, <i>A. Compactumi> Reichenb., <i>Delphinium gracilei> DC., <i>D. pentagynumi> Lam., <i>D. verdunensei> Balbis (= <i>D. cardiopetalumi> DC., <i>D. Requieniii> DC.. <i>Consolida orientalisi> (Gay Schröd, subsp. <i>orientalis> i <i>C. pubescensi> (OC. Soó. distributed in the Iberian Peninsula, and <i>A . napellusi> L. s. Str. (from England, <i>D. montanumi> DC. (from France, <i>D. nanumi> Dc. subsp. <i>elongatum> (Boiss Blanché & al. (= <i>D. peregrinumi> L. var. <i>elongatum> Boiss. (from Morocco i <i>D. pictumi> Willd. (from Mallorca are reviewed. The alkaloid content, structural types. and oxygenation patterns are discussed with respect to related species.<br>>[ca] Es revisen els alcaloides diterpènics obtinguts d'<i>Aconitum napellusi> L. subsp. <i>castellanum> Molera & Blanché, <i>A. Burnatiii> Gayer, <i>A. Compactumi> Reichenb., <i>Delphinium gracilei> DC., <i>D. pentagynumi> Lam., <i>D. verdunensei> Balbis (= <i>D. cardiopetalumi> DC., <i>D. Requieniii> DC.. <i>Consolida orientalisi> (Gay Schröd, subsp. <i>orientalis> and <i>C. pubescensi> (OC. Soó. distribuïts a la Península Ibèrica, així com d'<i>A . napellusi> L. s. Str. (d'Anglaterra, <i>D. montanumi> DC. (de França, <i>D. nanumi> Dc. subsp. <i>elongatum> (Boiss Blanché & al. (= <i>D. peregrinumi> L. var. <i>elongatum> Boiss. (del Marroc i <i>D. pictumi> Willd. (de Mallorca. El contingut en alcaloides, llurs tipus estructurals i models d'oxigenació són discutits en relació a d'alt res espècies afins.

  17. Evaluation of production samples of the scintillators LaBr3:Ce andLaCl3:Ce

    Energy Technology Data Exchange (ETDEWEB)

    Choong, Woon-Seng; Derenzo, Stephen E.; Moses, William W.

    2005-09-15

    We report on the evaluation of the performance of two recently developed scintillator materials, LaCl{sub 3}:Ce and LaBr{sub 3}:Ce, at the task of gamma ray spectroscopy. Their performance is compared to a standard scintillator used for gamma ray spectroscopy--a 25 mm diameter 25 mm tall cylinder of NaI:Tl. We measure the pulse height, energy resolution, and full-energy efficiency of production LaBr{sub 3}:Ce and LaCl{sub 3}:Ce scintillation crystals of different sizes and geometries for a variety of gamma-ray energies. Using production rather than specially selected crystals will establish whether immediate large-scale use is feasible. The crystal is excited by gamma rays from one of six isotopic sources ({sup 125}I, {sup 241}Am, {sup 57}Co, {sup 22}Na, {sup 137}Cs, and {sup 60}Co) placed 15 cm away from the scintillator. Our measurements show that both LaCl{sub 3} and LaBr{sub 3} outperform NaI:Tl in almost all cases. They outperform NaI:Tl at all energies for the photopeak fraction and counting rate measurements, and for energy resolution at higher energies (above 200 keV for LaCl{sub 3} and 75 keV for LaBr{sub 3}). The performance of production crystals is excellent and these scintillators should be considered for immediate use in systems where stopping power and energy resolution are crucial.

  18. Effect of Aromatic Oil on Phase Dynamics of S-SBR/BR Blends fro Passenger Car Tire Treads

    NARCIS (Netherlands)

    Rathi, A.; Hernández, M.; Dierkes, W.K.; Noordermeer, J.W.M.; Bergmann, C.; Trimbach, J.; Blume, A.

    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 p

  19. 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.

  20. Structural, vibrational, and electrical study of compressed BiTeBr

    Science.gov (United States)

    Sans, J. A.; Manjón, F. J.; Pereira, A. L. J.; Vilaplana, R.; Gomis, O.; Segura, A.; Muñoz, A.; Rodríguez-Hernández, P.; Popescu, C.; Drasar, C.; Ruleova, P.

    2016-01-01

    Compresed BiTeBr has been studied from a joint experimental and theoretical perspective. Room-temperature x-ray diffraction, Raman scattering, and transport measurements at high pressures have been performed in this layered semiconductor and interpreted with the help of ab initio calculations. A reversible first-order phase transition has been observed above 6-7 GPa, but changes in structural, vibrational, and electrical properties have also been noted near 2 GPa. Structural and vibrational changes are likely due to the hardening of interlayer forces rather than to a second-order isostructural phase transition while electrical changes are mainly attributed to changes in the electron mobility. The possibility of a pressure-induced electronic topological transition and of a pressure-induced quantum topological phase transition in BiTeBr and other bismuth tellurohalides, like BiTeI, is also discussed.

  1. Ca2+-Doped CeBr3 Scintillating Materials

    Energy Technology Data Exchange (ETDEWEB)

    Guss, Paul [NSTec; Foster, Michael E. [SNL; Wong, Bryan M. [SNL; Doty, F. Patrick [SNL; Shah, Kanai [RMD; Squillante, Michael R. [RMD; Shirwadkar, Urmila [RMD; Hawrami, Rastgo [RMD; Tower, Josh [RMD; Yuan, Ding [NSTec

    2014-01-01

    Despite the outstanding scintillation performance characteristics of cerium tribromide (CeBr3) and cerium-activated lanthanum tribromide, their commercial availability and application are limited due to the difficulties of growing large, crack-free single crystals from these fragile materials. This investigation employed aliovalent doping to increase crystal strength while maintaining the optical properties of the crystal. One divalent dopant (Ca2+) was used as a dopant to strengthen CeBr3 without negatively impacting scintillation performance. Ingots containing nominal concentrations of 1.9% of the Ca2+ dopant were grown. Preliminary scintillation measurements are presented for this aliovalently doped scintillator. Ca2+-doped CeBr3 exhibited little or no change in the peak fluorescence emission for 371 nm optical excitation for CeBr3. The structural, electronic, and optical properties of CeBr3 crystals were studied using the density functional theory within the generalized gradient approximation. The calculated lattice parameters are in good agreement with the experimental data. The energy band structures and density of states were obtained. The optical properties of CeBr3, including the dielectric function, were calculated.

  2. Ecotoxicity of glyphosate and aterbane® br surfactant on guaru (Phalloceros caudimaculatus = Ecotoxicologia do glifosato e surfactante aterbane® br para guaru (Phalloceros caudimaculatus

    Directory of Open Access Journals (Sweden)

    Natália Sayuri Shiogiri

    2010-07-01

    Full Text Available 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 (I50;96h and assess water quality variables for glyphosate in the Rodeo® formulation, Aterbane® BR surfactant and mixtures of glyphosate + 0.5% and 1.0% of surfactant, for the guaru fish (Phallocerus caudimaculatus. The guaru was exposed to increasing concentrationsof glyphosate and a mixture of glyphosate + 0.5 and 1.0% of surfactant. The mixture of glyphosate and glyphosate + 0.5 and 1.0% of surfactant showed (LC (I50;96h > 975.0 mg L-1. For the surfactant, the rate was 5.81 mg L-1. The glyphosate and mixtures of glyphosate + 0.5% and 1.0% of surfactant caused a decrease in pH and dissolved oxygen and increased the electrical conductivity of water. Glyphosate in the Rodeo® formulation and the mixtures with surfactantAterbane® BR can be classified as practically nontoxic, whereas surfactant Aterbane® BR can be considered as moderately toxic to guaru.As macrófitas aquáticas são importantes componentes dos ecossistemas, porém elas têm se tornado um problema pela sua ocorrência em diversas regiões. Alguns estudos visam comprovar a eficácia dos herbicidas no controle dessas macrófitas, porém, poucos trabalhos relatam os possíveis efeitos ecotoxicológicos. Assim, o objetivo deste trabalho foi estimar a toxicidade aguda (LC (I50;96h e avaliar as variáveis de qualidade de água para o glifosato na formulação Rodeo®, o surfactante Aterbane® BR e das misturas de glifosato + 0,5 e 1,0% do surfactante, para o peixe guaru (Phallocerus caudimaculatus. Para tanto, o guaru foi exposto a concentrações de glifosato e da mistura do glifosato + 0,5 e 1,0% do

  3. Theoretical Study on the Reaction Mechanism of F2+2HBr=2HF+Br2

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The gas phase reaction mechanism of F2 + 2HBr = 2HF + Br2 has been investigated by (U)MP2 at 6-311G** level, and a series of four-center and three-center transition states have been obtained. The reaction mechanism was achieved by comparing the activation energy of seven reaction paths, i.e. the dissociation energy of F2 is less than the activation energy of the bimolecular elementary reaction F2 + HBr → HF + BrF. Thus it is theoretically proved that the title reaction occurs more easily inthe free radical reaction with three medium steps.

  4. Balloon-borne stratospheric BrO measurements: comparison with Envisat/SCIAMACHY BrO limb profiles

    OpenAIRE

    Dorf, M.; H. Bösch; Butz, A.; Camy-Peyret, C.; Chipperfield, M. P.; Engel, A.; Goutail, F.; Grunow, K.; Hendrick, F.; Hrechanyy, S.; Naujokat, B.; J.-P. Pommereau; Van Roozendael, M.; Sioris, C.; Stroh, F.

    2006-01-01

    International audience; 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...

  5. Supervisory governance <br> The case of the <i>Dutch Consumer Authorityi>

    Directory of Open Access Journals (Sweden)

    Michiel A. Heldeweg

    2006-06-01

    Full Text Available This article concerns the impact of the Regulation on consumer protection cooperation, especially with regard to the introduction of a public law supervisory authority, on the primarily civil law and self-regulatory Dutch concept of supervision and enforcement in consumer law. The response to this regulation has been to introduce a dual system of enforcement (separating civil law and public law enforcement in which the new Dutch Consumer Authority is to act in accordance with the subsidiarity principle (intervening only when the market itself fails to respond adequately. The major question is whether this new ‘hybrid’ concept of dualism and subsidiarity will be sustainable or if a full ‘publicisation’ of Dutch consumer protection law should be expected. Important determining factors are the positioning of the Consumer Authority in both the European network and in several national networks with both public and private law partners. A key issue is how responsibility for consumer protection will be distributed through these networks. Finding a balance between, especially, the role of the European Commission (in the European network and ministerial responsibility (for the Consumer Authority is necessary to enable the Consumer Authority to create sufficient trust within these networks so as to make dualism and subsidiarity possible.

  6. Notes on Euphorbia subgenus <i>Euphorbia> in Ethiopia

    Directory of Open Access Journals (Sweden)

    Gilbert, M. G.

    1992-12-01

    Full Text Available Precursory notes on <i>Euphorbia> subgen. <i>Euphorbia> for the Flora of Ethiopia are given. Revised synonymies are given for <i>E. abyssinica, E. ampliphyllai> and <i>E. polyacanthai>. Six species: <i>E. burgeni> M.G. Gilbert, <i>E. nigrispinoidesi> M.G. Gilbert, <i>E. sebsebeii> M.G.Gilbert, <i>E. bitataënsisi> M.G. Gilbert, <i>E. baleënsisi> M.G. Gilbert and <i>E. awashensisi> M.G. Gilbert, and one subspecies: <i>E. septentrionalisi> subsp. <i>gamugofana> M.G. Gilbert, are described as new.<br>>Es presenten unes notes preliminars per a la Flora d'Etiòpia sobre <i>Euphorbia> L. subgen. <i>Euphorbia>. Es do nen les sinonímies revisades per a <i>E. abyssinica, E. Ampliphyllai> i <i>E. poJyacanthai>. Es descriuen sis espècies noves (<i>E. Burgerii> M.a . Gilbert, <i>E. nigrispinoidesi> M.O. Gilbert, <i>E. sebsebeii> M.a . Gilbert, <i>E. bitataënsisi> M.O. Gilbert, <i>E. baleënsisi> M.G. Gilbert i <i>E. awashensisi> M.G. Gilbert i una subespècie (<i>E. septentrionalisi> subsp. <i>gamugofana> M.G. Gilbert.

  7. 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.)

  8. 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.

  9. 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

  10. 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 ...

  11. Observations of solar radio emissions in meter wavelengths carried by CALLISTO-BR

    Science.gov (United States)

    Fernandes, F. C. R.; Silva, R. D. C.; Sodré, Z. A. L.; Costa, J. E. R.; Sawant, H. S.

    2012-04-01

    Two Callisto-type (Compound Astronomical Low-cost Low frequency Instrument for Spectroscopy and Transportable Observatory) spectrographs are in operation in Cachoeira Paulista, Brazil, since 2010. The CALLISTO-BR integrates the e-Callisto network consisting of several radio spectrographs distributed around the world, for provide continuous monitoring (24 hours) of the solar activity in the meter frequency range of 45 - 870 MHz. The solar radio emissions observations carried out by Callisto can be used as a diagnostic of several physical processes on the Sun. Here, we present the observations of several bursts recorded by CALLISTO-BR, such as type I bursts associated with a long lasting noise storm, recorded on March 30, 2010 in the typical frequency band around 200 MHz; a group of normal drifting type III bursts recorded in March 31, 2010 and also in February 15, 2011 and a rarely observed broadband (~180 - 800 MHz) continuum emission presenting positive frequency drifting (from low to high frequencies), suggesting the source is moving towards photosphere. Observations of type II and type IV bursts were also recorded. Details of these and many other solar radio emissions recorded by CALLISTO-BR will be presented and their implications for the solar activity and space weather investigations will be discussed.

  12. Atomic force microscopic study on topological structures of pBR322 DNA

    Institute of Scientific and Technical Information of China (English)

    张平城; 白春礼; 成英俊; 方晔; 王中怀; 黄熙泰

    1996-01-01

    Plasmid pBR322 DNA (0.5mg/mL) isolated from Escherichia coli HB101 was suspended in Tris-HCl-EDTA (1 mol/L - 0.1 mol/L, pH8.5); then a drop of the above solution was deposited on freshly cleaved mica substrate. After adsorption for about 1 min, the sample was stained with phosphotungstic acid. The residua] solution was removed with a piece of filter paper. Afterwards the sample was imaged with a home-made atomic force microscope (AFM) in air. The AFM images of pBR322 DNA with a molecular resolution have been obtained. These images show that pBR322 DNA exists in several different topological structures: (i) relaxed circular DNA with a different diameter; (ii) supercondensed DNA with different particle sizes; (iii) dimeric catenane connected by one relaxed circular molecule and another dose-compacted molecule which might be either supercoiled or intramolecular knotted form; (iv) oligomeric catenane with multiple irregular molecules in which DNA is interlocked into a complex oligomer; (v) possibly-existing

  13. Current status of the new LaBr{sub 3}:Ce detector array GALATEA

    Energy Technology Data Exchange (ETDEWEB)

    Walz, Christopher; Neumann-Cosel, Peter von; Ries, Philipp; Pietralla, Norbert; Scheit, Heiko; Schnorrenberger, Linda [Technische Univ. Darmstadt (Germany). Inst. fuer Kernphysik; Lefol, Ronan [University of Saskatchewan (Canada)

    2013-07-01

    In contrast to common scintillation materials like NaI and BaF{sub 2} the recently developed LaBr{sub 3}:Ce detectors allow measurements with excellent time resolution and high efficiency while retaining a good energy resolution. To perform successful (e,e{sup '}γ) and (γ,γ{sup '}γ) coincidence experiments at the linear electron accelerator S-DALINAC all three features are of utmost importance. We present the current status of the new LaBr{sub 3}:Ce detector array GALATEA (GAmma LAnthanum bromide Top Efficiency Array) consisting of 18 large 3'' x 3'' LaBr{sub 3}:Ce detectors. One focus is on the completely digital DAQ based on flash ADCs and newly developed pulse shape analysis methods for timing and particle identification. The performance of GALATEA is discussed regarding energy resolution, time resolution, linearity and efficiency. The results are compared to GEANT4 simulations.

  14. MAX-DOAS measurements of BrO and NO2 in the marine boundary layer

    Science.gov (United States)

    Leser, H.; Hönninger, G.; Platt, U.

    2003-05-01

    During a cruise of the German research vessel Polarstern from Bremerhaven, Germany to Capetown, South Africa in October 2000 mid latitude tropospheric bromine oxide (BrO) and nitrogen dioxide (NO2) abundances were investigated by ground-based MAX-DOAS (scattered light Multi Axis Differential Optical Absorption Spectroscopy). By comparing the slant column densities of absorbers measured at different elevation angles above the horizon (5° to 90°) it is possible to draw conclusions regarding the vertical distribution of the investigated absorbers (i.e., BrO and NO2). During a period of 2 days in the region north of the Canary Islands (around 35°N, 13°W) significant boundary layer BrO in the 1 ppt range was found. For the remaining time all data points ranged below the detection limit. Boundary layer NO2 was found near Europe and the Canary Islands with mixing ratios in the range of several ppb. In the remote marine air south west of Africa upper limits were derived.

  15. <i>Revista de Folklorei>

    Directory of Open Access Journals (Sweden)

    Díaz, Joaquín

    2002-06-01

    Full Text Available The author, founder and chief underwriter of <i>Revista de Folklorei>, voices his view of the world of research of traditional culture, as well as the aims he pursued in founding one of the journals of folklore of longest standing in Spain.<br>>El fundador y principal sostenedor de la <i>Revista de Folklorei> plantea en este escrito su visión personal sobre el mundo de la investigación acerca de la cultura tradicional y los objetivos que se fijó al emprender la publicación de una de las revistas especializadas más largas y continuas con que contamos en España.

  16. Eesti annab oma panuse EL-i armeesse / Merit Kopli

    Index Scriptorium Estoniae

    Kopli, Merit, 1969-

    2000-01-01

    EL-i, NATO ja kandidaatriikide kaitseministrid arutasid Brüsselis EL-i kriisireguleerimisjõudude loomist. Eesti kaitseminister Jüri Luik tegi EL-ile teatavaks Eesti panuse. Diagramm: EL-i kiirreageerimisjõud

  17. Eesti annab oma panuse EL-i armeesse / Merit Kopli

    Index Scriptorium Estoniae

    Kopli, Merit, 1969-

    2000-01-01

    EL-i, NATO ja kandidaatriikide kaitseministrid arutasid Brüsselis EL-i kriisireguleerimisjõudude loomist. Eesti kaitseminister Jüri Luik tegi EL-ile teatavaks Eesti panuse. Diagramm: EL-i kiirreageerimisjõud

  18. Danske bygningers energibehov i 2050

    DEFF Research Database (Denmark)

    Kragh, Jesper; Wittchen, Kim Bjarne

    I rapporten belyses mulighederne for at energiforbedre den eksisterende danske bygningsmasse frem mod 2050, så bygningsmassen kan yde sit bidrag til at gøre Danmark fri af fossile brændsler. Arbejdet tager udgangspunkt i tidligere gennemførte analyser af potentialet for energiforbedringer i den e...

  19. 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.

  20. The 3-kind ideals relation and properties of BR0-algebras%BR0-代数三种理想的关系和性质

    Institute of Scientific and Technical Information of China (English)

    王娜; 吴洪博

    2013-01-01

    为了进一步研究BR0-代数的结构.首先在BR0-代数中给出了蕴涵理想,⊙-理想和V-理想的定义;其次,讨论了BR0-代数中这三种理想的关系;最后,研究了BR0-代数中理想的一些性质,并证明了极大理想存在定理.%In order to study the structure of BR0-algebras in depth,firstly,the definitions of implicative ideal,⊙-ideal and V-ideal are given on the BR0-algebras; Secondly,the relation of 3-kind ideals is discussed in the BR0-algebras; Finally,some properties of ideal are researched in the BR0-algebras and maximal ideal existence theorem is proved.

  1. The NQR observation of spin-Peierls transition in an antiferromagnetic MX-chain complex [NiBr(chxn)2]Br2.

    Science.gov (United States)

    Takaishi, Shinya; Tobu, Yasuhiro; Kitagawa, Hiroshi; Goto, Atsushi; Shimizu, Tadashi; Okubo, Takashi; Mitani, Tadaoki; Ikeda, Ryuichi

    2004-02-18

    81Br Nuclear quadrupole resonance (NQR) measurement was performed in an S = 1/2 one-dimensional Heisenberg antiferromagnetic metal complex [NiBr(chxn)2]Br2 (chxn: 1R,2R-diaminocyclohexane), having a halogen-bridged MX chain structure -Br-Ni3+-Br-Ni3+-Br-. Two 81Br NQR signals were observed below 40 K, while a single signal was observed above 130 K, showing the presence of two nonequivalent bridging Br sites below 40 K. This NQR result together with previously reported magnetic susceptibility and X-ray results indicate the occurrence of a transition into a spin-Peierls state between 40 and 130 K. This communication reports the first spin-Peierls transition in metal complexes in which pure d electrons contribute to the magnetism. In addition, we demonstrated a new experimental method for studying a spin-Peierls system.

  2. New insight into halogen release from experimental studies on BrO/Br ratios in volcanic plumes

    Science.gov (United States)

    Bobrowski, Nicole; Wittmer, Julian; Liotta, Marcello; Calabrese, Sergio; Giuffrida, Giovanni; Brusca, Lorenzo; Platt, Ulrich

    2014-05-01

    Since the discovery of BrO in a volcanic plume (Bobrowski et al. 2003) many measurements have been performed as well as modelling to understand the radical chemistry in volcanic plumes, in particular, the interaction between volcanic gas species, released under strongly reduced conditions, and the oxidizing atmosphere. Besides the goal in atmospheric chemistry to better determine the impact of volcanic emission (e.g. reactive bromine) on the local (and maybe global) scale, volcanologists also have an interest to understand if the BrO/SO2 ratios can be used as a monitoring parameter giving further insides in dynamic processes of volcanoes. However, one of the arguments which potentially makes volcanological interpretations difficult is the reactivity of BrO. Therefore it is, of great importance to link the measurements of BrO and gaseous hydrogen bromide to the total emission flux of bromine in order to estimate the pristine gas composition released from magmas. In particular, trace gas composition of the surrounding atmosphere, the volcanic gas composition and meteorological parameters can all potentially effect the formation of BrO and might have to be considered. Some of these factors potentially also influence near source (crater rim) in-situ measurement. We need to answer the question: Can we correlate BrO measurements to the total bromine outgassing? Only with this knowledge we can relate changes of the measured gas ratios (BrO/SO2) to the volcanic fluids emitted by the underlying magma and can interpret data as signals from depth, which provide insight on the degassing of magmatic bodies inside the Earth. Some studies indicate that the BrO/SO2 ratio is close to a temporarily equilibrium already after only few minutes of the gas emission from the vent (e.g. Bobrowski and Giuffrida, 2012). This equilibrium seems to be relatively independent from meteorological parameters except for extreme conditions. We here present an empirical approach to answer the above

  3. 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.

  4. Atmospheric test of the J(BrONO2)/kBrO+NO2 ratio: implications for total stratospheric Bry and bromine-mediated ozone loss

    Science.gov (United States)

    Kreycy, S.; Camy-Peyret, C.; Chipperfield, M. P.; Dorf, M.; Feng, W.; Hossaini, R.; Kritten, L.; Werner, B.; Pfeilsticker, K.

    2013-07-01

    We report on time-dependent O3, NO2 and BrO profiles measured by limb observations of scattered skylight in the stratosphere over Kiruna (67.9° N, 22.1° E) on 7 and 8 September 2009 during the autumn circulation turn-over. The observations are complemented by simultaneous direct solar occultation measurements around sunset and sunrise performed aboard the same stratospheric balloon payload. Supporting radiative transfer and photochemical modelling indicate that the measurements can be used to constrain the ratio J(BrONO2)/kBrO+NO2, for which at T = 220 ± 5 K an overall 1.7 (+0.4 -0.2) larger ratio is found than recommended by the most recent Jet Propulsion Laboratory (JPL) compilation (Sander et al., 2011). Sensitivity studies reveal the major reasons are likely to be (1) a larger BrONO2 absorption cross-section σBrONO2, primarily for wavelengths larger than 300 nm, and (2) a smaller kBrO+NO2 at 220 K than given by Sander et al. (2011). Other factors, e.g. the actinic flux and quantum yield for the dissociation of BrONO2, can be ruled out. The observations also have consequences for total inorganic stratospheric bromine (Bry) estimated from stratospheric BrO measurements at high NOx loadings, since the ratio J(BrONO2)/kBrO+NO2 largely determines the stratospheric BrO/Bry ratio during daylight. Using the revised J(BrONO2)/kBrO+NO2 ratio, total stratospheric Bry is likely to be 1.4 ppt smaller than previously estimated from BrO profile measurements at high NOx loadings. This would bring estimates of Bry inferred from organic source gas measurements (e.g. CH3Br, the halons, CH2Br2, CHBr3, etc.) into closer agreement with estimates based on BrO observations (inorganic method). The consequences for stratospheric ozone due to the revised J(BrONO2)/kBrO+NO2 ratio are small (maximum -0.8%), since at high NOx (for which most Bry assessments are made) the enhanced ozone loss by overestimating Bry is compensated for by the suppressed ozone loss due to the underestimation

  5. Kinetics and mechanism of the disproportionation of BrO radicals

    Science.gov (United States)

    Sander, S. P.; Watson, R. T.

    1981-01-01

    In the reported investigation, measurements were conducted of the rate constant for the reaction BrO + BrO yields products (1), taking into account the temperature range from 223 to 338 K and the pressure range from 50 to 475 torr of He. The flash photolysis-ultraviolet absorption technique was employed in the experiments. Two independent approaches were used to determine the relative rates of the two reaction branches, BrO + BrO yields BrOO + Br (1a), and BrO + BrO yields Br2 + O2 (1b), one dependent and the other independent of the BrO absorption cross section with the results being in excellent agreement. The rate constant, k(1), was found to be independent of pressure.

  6. Molecular and functional ultrasound imaging in differently aggressive breast cancer xenografts using two novel ultrasound contrast agents (BR55 and BR38).

    Science.gov (United States)

    Bzyl, Jessica; Lederle, Wiltrud; Rix, Anne; Grouls, Christoph; Tardy, Isabelle; Pochon, Sibylle; Siepmann, Monica; Penzkofer, Tobias; Schneider, Michel; Kiessling, Fabian; Palmowski, Moritz

    2011-09-01

    To characterise clinically translatable long-circulating (BR38) and VEGFR2-targeted (BR55) microbubbles (MB) and to assess their ability to discriminate breast cancer models with different aggressiveness. The circulation characteristics of BR38 and BR55 were investigated in healthy mice. The relative blood volume (rBV) of MDA-MB-231 (n = 5) or MCF-7 (n = 6) tumours was determined using BR38. In the same tumours in-vivo binding specificity of BR55 was tested and VEGFR2 expression assessed. Data validation included quantitative immunohistological analysis. BR38 had a longer blood half-life than BR55 (>600 s vs. 218 s). BR38-enhanced ultrasound showed greater vascularisation in MDA-MB-231 tumours (p = 0.022), which was in line with immunohistology (p = 0.033). In-vivo competitive binding experiments proved the specificity of BR55 to VEGFR2 (p = 0.027). Binding of BR55 was significantly higher in MDA-MB-231 than in MCF-7 tumours (p = 0.049), which corresponded with the VEGFR2 levels found histologically (p = 0.015). However, differences became smaller when normalising the levels of BR55 to the rBV. BR38 and BR55 are well suited to characterising and distinguishing breast cancers with different angiogenesis and aggressiveness. Long-circulating BR38 MB allow extensive 3-dimensional examinations of larger or several organs. BR55 accumulation faithfully reflects the VEGFR2 status in tumours and depicts even small differences in angiogenesis.

  7. Brändin esiintyvyys blogeissa - Case Adidas

    OpenAIRE

    Kolehmainen, Tiia

    2013-01-01

    Tämän opinnäytetyön tarkoituksena oli selvittää adidas -brändin blogiesiintyvyys suomalaisissa blogeissa. Tutkimuksen tavoitteena oli saada käsitys siitä, millaisissa muodoissa adidas-brändi esiintyy Suomen suosituimmissa blogeissa. Tutkimuksessa tutkittiin myös Adidaksen kampanjan blogiesiintyvyyttä. Opinnäytetyön toimeksiantajana toimi Adidas Suomi Oy, joka on osa globaalia Adidas Groupia. Yritys on yksi maailman johtavimmista urheilutuotemerkeistä. Tutkimuksen teoreettisessa osuud...

  8. SiBr4--prediction and determination of crystal structures.

    Science.gov (United States)

    Wolf, Alexandra K; Glinnemann, Jürgen; Schmidt, Martin U; Tong, Jianwei; Dinnebier, Robert E; Simon, Arndt; Köhler, Jürgen

    2009-06-01

    For SiBr4 no crystal structures have been reported yet. In this work the crystal structures of SiBr4 were predicted by global lattice-energy minimizations using force-field methods. Over an energy range of 5 kJ mol(-1) above the global minimum ten possible structures were found. Two of these structures were experimentally determined from X-ray synchrotron powder diffraction data: The low-temperature beta phase crystallizes in P2(1)/c, the high-temperature alpha phase in Pa3. Temperature-dependant X-ray powder diffraction shows that the phase transition occurs at 168 K.

  9. SiBr4 - Prediction and Determination of Crystal Structures

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, A.; Glinnemann, J; Schmidt, M; Tong, J; Dinnebier, R; Simon, A; Kohler, J

    2009-01-01

    For SiBr4 no crystal structures have been reported yet. In this work the crystal structures of SiBr4 were predicted by global lattice-energy minimizations using force-field methods. Over an energy range of 5 kJ mol-1 above the global minimum ten possible structures were found. Two of these structures were experimentally determined from X-ray synchrotron powder diffraction data: The low-temperature [beta] phase crystallizes in P21/c, the high-temperature [alpha] phase in Pa overline3. Temperature-dependant X-ray powder diffraction shows that the phase transition occurs at 168 K.

  10. Generalized Toda Mechanics Associated with Loop Algebra (ι)(Br)

    Institute of Scientific and Technical Information of China (English)

    YANG Zhan-Ying; ZHAO Liu; SHI Kang-Jie

    2005-01-01

    A class of generalization of Toda mechanics with long range interactions is constructed in this paper. These systems are associated with the loop algebras (ι)(Br) in the sense that their Lax matrices can be realized in terms of the c = 0 representations of the affine Lie algebras Br(1). We adopt a pair of ordered integers (m, n) to describe the Toda mechanics system when we present the equations of motion and the Hamiltonian structure. We also extract the classical r matrix which satisfy the classical Yang-Baxter relation. Such generalizations will become systems with noncommutative variables in the quantum case.

  11. Stratospheric BrONO2 observed by MIPAS

    Directory of Open Access Journals (Sweden)

    H. Fischer

    2008-11-01

    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.

  12. 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.

  13. Brändistrategian merkitys yrityksen digitaalisessa markkinoinnissa

    OpenAIRE

    2011-01-01

    Tämä tutkielma on kirjoitettu siksi, että olen aikaisemmin työskennellyt digitaalista markkinointia myyvän yrityksen palveluksessa. Kyseinen työnantaja, Advertising Media Finland Oy, on ollut tämän tutkielman toimeksiantaja. Työn tavoitteena oli selvittää, kuinka suuri merkitys brändistrategialla on suomalaisissa yrityksissä. Lisäksi pyrittiin selvittämään, mikä on suomalaisten yritysten brändi-identiteetin ja imagon merkitys digitaalisessa markkinoinissa. Näiden kahden asian lisäksi selvitet...

  14. A new bifunctional chelate, BrMe sub 2 HBED: An effective conjugate for radiometals and antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Mathias, C.J.; Connett, J.M.; Philpott, G.W.; Welch, M.J. (Washington Univ. School of Medicine, St. Louis, MO (USA)); Sun, Yizhen; Martell, A.E. (Texas A and M Univ., College Station (USA))

    1990-04-18

    A new bifunctional chelate, N-(2-hydroxy-3,5-dimethylbenzyl)-N{prime}-(2-hydroxy-5-(bromoacetamido)benzyl)ethylenediamine-N,-N{prime}-diacetic acid (BrMe{sub 2}HBED), was designed and synthesized to bind trivalent cationic metals with monoclonal antibodies. The stability constants (log values) for indium complexed with a similar ligand, HBED, were increased over those of more commonly used ligands DTPA and EDTA. Predictably, the increased metal-ligand complex stability would expedite the in vivo clearance from nontarget regions and perhaps enhance the localization of the radiolabeled antibody (Ab). BrMe{sub 2}HBED was conjugated with the Ab (24 h) and then radiolabeled with indium-111 citrate (24 h). Additionally, the Ab was radiolabeled by using conventional methods ({sup 111}In-DTPA and {sup 125}I-lactoperoxidase) and then compared by measuring the in vitro stability, in vitro immunoreactivity(IR), and in vivo distribution and clearance. A 10:1 BrMe{sub 2} HBED:Ab mole ratio resulted in good labeling efficiency with {sup 111}In and more importantly a very high IR. In a hamster tumor model, {sup 111}In-BrMe{sub 2} HBED-labeled monoclonal antibody (1A3) had high uptake in the tumor tissue and preferable blood clearance compared to either of the more conventional radiolabeled 1A3 monoclonal antibodies ({sup 111}In-DTPA or {sup 125}I-lactoperoxidase). 49 refs., 4 figs., 8 tabs.

  15. Ground-state proton decay of 69Br and implications for the 68Se astrophysical rapid proton-capture process waiting point.

    Science.gov (United States)

    Rogers, A M; Famiano, M A; Lynch, W G; Wallace, M S; Amorini, F; Bazin, D; Charity, R J; Delaunay, F; de Souza, R T; Elson, J; Gade, A; Galaviz, D; van Goethem, M-J; Hudan, S; Lee, J; Lobastov, S; Lukyanov, S; Matoš, M; Mocko, M; Schatz, H; Shapira, D; Sobotka, L G; Tsang, M B; Verde, G

    2011-06-24

    We report on the first direct measurement of the proton separation energy for the proton-unbound nucleus (69)Br. Bypassing the (68)Se waiting point in the rp process is directly related to the 2p-capture rate through (69)Br, which depends exponentially on the proton separation energy. We find a proton separation energy for (69)Br of Sp((69)Br )= -785(-40)(+34) keV; this is less bound compared to previous predictions which have relied on uncertain theoretical calculations. The influence of the extracted proton separation energy on the rp process occurring in type I x-ray bursts is examined within the context of a one-zone burst model.

  16. BR 0-代数的表示定理及其简化形式%The Representive Theorem and the Simplied Form of BR 0-Algebra

    Institute of Scientific and Technical Information of China (English)

    龚加安; 崔宏志; 吴洪博

    2016-01-01

    通过对基础模糊命题演算系统BL∗及相应的Lindenbaum代数的研究,给出了BR0-代数的格蕴涵表示形式,使得BR0-代数从定义形式上更加符合逻辑代数的特征,突出了BR0-代数和其他逻辑代数的区别与联系,其次,结合MV-代数,R0-代数和BR0-代数的关系给出了MV-代数的BR0-代数表示形式以及BR0-代数的简化形式。%Through study of basic fuzzy propositional calculus formal deductive system BL ∗ and Lindenbaum algebra,we get the lattice-implication representive theorem of BR0-algebra. This work conforms BR0-algebra to the features of logic algebra in definition,which protrudes the relations between BR0- algebra and other logic algebra. In addition,with the help of the relation between BR0-algebra and MV-algebra,R0-algebra,we have also given the simplied form of BR0-algebra and the BR0-algebra form of MV-algebra.

  17. Product analysis and kinetics of Br-initiated gas-phase oxidation of dimethyl sulphide; Produktanalyse und Kinetik der Br-initiierten Gasphasenoxidation von Dimethylsulfid

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.H.; Maurer, T.

    1996-07-01

    High Br concentrations in maritime environments may render the reaction between Br radicals and dimethyl sulphide an important process. According to the literature this system has as yet not been studied with a mind to clarifying the reaction mechanisms and performing a product analysis. Thus, for example, the decomposition of the DMS-Br adduct remains to be clarified. The purpose of the present study was therefore to examine the reaction between dimethyl sulphide and Br radicals and so gain information on the decomposition mechanism. This implied a determination of the velocity constant and a product analysis of the reaction between Br radicals and dimethyl sulphide. In addition the velocity constant of the reaction between Br radicals and dimethylsulphoxide (a consequent product of DMS oxidation) was to be determined. (orig.) [Deutsch] Hohe Br-Konzentrationen in maritimen Gebieten machen die Reaktion von Br-Radikalen mit Dimethylsulfid moeglicherweise zu einem wichtigen Prozess. In der Literatur fehlen eingehende Untersuchungen dieses Systems hinsichtlich der Aufklaerung der Reaktionsmechanismen und der Produktanalyse. So ist zum Beispiel der Zerfall des DMS-Br-Adduktes nicht aufgeklaert. Aus diesen Gruenden soll im Rahmen dieser Arbeit die Reaktion von Dimethylsulfid mit Br-Radikalen untersucht werden, um Informationen ueber den Abbaumechanismus zu erhalten. Darunter fallen die Bestimmung der Geschwindigkeitskonstanten und die Produktanalyse der Reaktion von Br-Radikalen mit Dimethylsulfid. Zusaetzlich soll die Geschwindigkeitskonstante der Reaktion vom Br-Radikalen mit Dimethylsulfoxid (einem Folgeprodukt der DMS-Oxidation) bestimmt werden. (orig.)

  18. 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

  19. Infrared absorption and fluorescence properties of Ho-doped KPb2Br5

    Science.gov (United States)

    Brown, Ei E.; Hömmerich, Uwe; Hyater-Adams, Simone; Oyebola, Olusola; Bluiett, Althea; Trivedi, Sudhir

    2014-03-01

    Spectroscopic properties of the 2 μm infrared (IR) emission (5I7 --> 5I8) from trivalent holmium (Ho3+) doped potassium lead bromide (KPb2Br5) are presented. The investigated Ho3+ doped KPb2Br5 (KPB) material was synthesized through purification of starting materials including multi-pass zone-refinement, bromination, and subsequently grown using horizontal Bridgman technique. The bromination process was critical for removing oxidic impurities and enhancing the quality of the crystal. Judd-Ofelt intensity parameters, radiative rates, branching ratios, and emission lifetimes were calculated and compared with results reported for Ho3+ doped KPb2Cl5 (KPC). Under resonant pumping (~1.907 μm), Ho: KPB showed a broad IR emission centered at ~2 μm with an exponential decay time of 7.1 ms at room temperature. The nearly temperature independent emission lifetime is consistent with a negligibly small non-radiative decay rate for the 5I7 excited state of Ho3+, as predicted by the multiphonon energy gap law. The optical absorption, emission and gain cross-sections of Ho: KPB were determined for the 2 μm transition. The Ho: KPB crystal was also evaluated as a potential solid-state material for laser cooling applications.

  20. 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.

  1. Large BR(h -> tau mu) in Supersymmetric Models

    CERN Document Server

    Hammad, Ahmed; Un, Cem Salih

    2016-01-01

    We analyze the Lepton Flavor Violating (LFV) Higgs decay h -> tau mu in three supersymmetric models: Minimal Supersymmetric Standard Model (MSSM), Supersymmetric Seesaw Model (SSM), and Supersymmetric B-L model with Inverse Seesaw (BLSSM-IS). We show that in generic MSSM, with non-universal slepton masses and/or trilinear couplings, it is not possible to enhance BR(h -> tau mu) without violating the experimental bound on the BR(tau -> mu gamma). In SSM, where flavor mixing is radiatively generated, the LFV process mu -> e gamma strictly constrains the parameter space and the maximum value of BR(h -> tau mu) is of order 10^-10, which is extremely smaller than the recent results reported by the CMS and ATLAS experiments. In BLSSM-IS, with universal soft SUSY breaking terms at the grand unified scale, we emphasize that the measured values of BR(h -> tau mu) can be accommodated in a wide region of parameter space without violating LFV constraints. Thus, confirming the LFV Higgs decay results will be a clear signa...

  2. Infections fongiques des brûlé : revue

    Science.gov (United States)

    Arnould, JF.; Le Floch, R.

    2015-01-01

    Summary Les infections fongiques locales ou générales sont souvent d’une extrême gravité chez les brûlés. Les brûlés combinent de nombreux facteurs de risque à une immunodépression induite par la brûlure. Les infections de plaies sont le fait des genres Candida, Aspergillus et des agents de mucormycoses. Ces deux derniers cas sont à l’origine de lésions particulièrement sévères. Leur diagnostic repose sur la biopsie cutanée avec examens mycologique et anatomopathologique. Le traitement est essentiellement chirurgical, associé à une antibiothérapie adaptée. Les septicémies sont le fait de levures, essentiellement du genre Candida. Le diagnostic en est difficile dans le contexte des brûlés et repose souvent sur une forte suspicion clinique. Leur traitement repose sur les échinocandines et plus secondairement sur le fluconazole. PMID:26668558

  3. 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.

  4. Nuclear-induced XeBr/asterisk/ photolytic laser model

    Science.gov (United States)

    Wilson, J. W.

    1980-01-01

    Parameters for a photolytically pumped alkyl iodide lasant gas by the nuclear-induced XeBr excimer fluorescence are calculated according to a detailed kinetic model. High gain on the atomic iodine 2P1/2 state is estimated and 100-mJ pulses with an average power output on the order of 1 kW appear possible.

  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. Pressure and temperature dependence kinetics study of the NO + BrO yielding NO2 + Br reaction - Implications for stratospheric bromine photochemistry

    Science.gov (United States)

    Watson, R. T.; Sander, S. P.; Yung, Y. L.

    1979-01-01

    The reactivity of NO with BrO radicals over a wide range of pressure (100-700 torr) and temperature (224-398 K) is investigated using the flash photolysis-ultraviolet absorption technique. The flash photolysis system consists of a high-pressure xenon arc light source, a reaction cell/gas filter/flash lamp combination, and a 216.5 half-meter monochromator/polychromator/spectrography for wavelength selectivity. The details of the reaction and its corresponding Arrhenius expression are identified. The results are compared with previous measurements, and atmospheric implications of the reaction are discussed. The NO + BrO yielding NO2 + Br reaction is shown to be important in controlling the concentration ratios of BrO/Br and BrO/HBr in the stratosphere, but this reaction does not affect the catalytic efficiency of BrOx in ozone destruction.

  7. Gamma spectroscopy with LaBr{sub 3} and Lyso for its application in nuclear medicine; Espectroscopia gamma con LaBr{sub 3} y LYSO para su aplicacion en medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez V, M.; Murrieta, T.; Martinez D, A. [UNAM, Instituto de Fisica, Apdo. Postal 20-364, 01000 Mexico D. F. (Mexico); Alva S, H., E-mail: mercedes@fisica.unam.m [UNAM, Facultad de Medicina, Unidad PET/CT-Ciclotron, Edificio de Investigacion P. B., Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2011-07-01

    Image formation in nuclear medicine is based on the detection of radiation emitted from a small quantity of a radiopharmaceutical administered to patients. This requires high detection efficiency, good spatial resolution and the ability to identify the energy of the incident radiation. These and other properties of detector materials for gamma radiation are reviewed. Standard detector calibration and characterization procedures are described, and the results from gamma spectroscopy measurements for sodium iodide (NaI:Tl), conventional scintillator widely used in nuclear medicine applications, and two other novel scintillation crystals, lanthanum bromide (LaBr{sub 3}) and lutetium-yttrium oxy orthosilicate (Lyso) are presented. Both materials showed a linear energy response from 80 to 1332 KeV, and within this energy interval, LaBr{sub 3} had a superior energy resolution compared to Lyso and NaI:Tl. These and other new materials are expected to replace those used in current detectors for nuclear medicine scanners. (Author)

  8. 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

  9. Thermal properties for the thermal-hydraulics analyses of the BR2 maximum nominal heat flux.

    Energy Technology Data Exchange (ETDEWEB)

    Dionne, B.; Kim, Y. S.; Hofman, G. L. (Nuclear Engineering Division)

    2011-05-23

    This memo describes the assumptions and references used in determining the thermal properties for the various materials used in the BR2 HEU (93% enriched in {sup 235}U) to LEU (19.75% enriched in {sup 235}U) conversion feasibility analysis. More specifically, this memo focuses on the materials contained within the pressure vessel (PV), i.e., the materials that are most relevant to the study of impact of the change of fuel from HEU to LEU. This section is regrouping all of the thermal property tables. Section 2 provides a summary of the thermal properties in form of tables while the following sections present the justification of these values. Section 3 presents a brief background on the approach used to evaluate the thermal properties of the dispersion fuel meat and specific heat capacity. Sections 4 to 7 discuss the material properties for the following materials: (i) aluminum, (ii) dispersion fuel meat (UAlx-Al and U-7Mo-Al), (iii) beryllium, and (iv) stainless steel. Section 8 discusses the impact of irradiation on material properties. Section 9 summarizes the material properties for typical operating temperatures. Appendix A elaborates on how to calculate dispersed phase's volume fraction. Appendix B shows the evolution of the BR2 maximum heat flux with burnup.

  10. 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.

  11. Pharmacological characterization and positron emission tomography evaluation of 4-[{sup 76}Br]bromodexetimide and 4-[{sup 76}Br]bromolevetimide for investigations of central muscarinic cholinergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Loc' h, C.; Kassiou, M.; Strijckmans, V.; Bottlaender, M.; Katsifis, A.; Schmid, L.; Maziere, M.; Lambrecht, R. M.; Maziere, B

    1996-04-01

    4-[{sup 76}Br]bromodexetimide and its inactive enantiomer 4-[{sup 76}Br]bromolevetimide were prepared via electrophilic bromodesilylation using chloramine-T and no-carrier-added (NCA) [{sup 76}Br]NH{sub 4}. In vitro, B{sub max} measured on rat cortex membranes were 3.7 {+-} 0.2 and <0.07 pmol/mg protein for 4-[{sup 76}Br]bromodexetimide and 4-[{sup 76}Br]bromolevetimide, respectively. The k{sub D} of 4-[{sup 76}Br]bromodexetimide was 1.9 {+-} 0.3 nM. In vivo studies in rats showed specific uptake of 4-[{sup 76}Br]bromodexetimide in cortex, striatum, thalamus and hippocampus. No specific uptake was observed with 4-[{sup 76}Br]bromolevetimide. With [{sup 76}Br]bromodexetimide, positron emission tomography (PET) studies in primates demonstrated a preferential accumulation of the radioactivity in the cortex and striatum which was displaced to the level of cerebellum by dexetimide. With 4-[{sup 76}Br]bromolevetimide, the radioactivity concentrations in the cortex and striatum were similar to that of cerebellum.

  12. Measurement of the branching fraction Br(Bs -> Ds(*) Ds(*))

    CERN Document Server

    Abazov, V M; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguiló, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Askew, A; Assis-Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Barfuss, A F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benítez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boline, D; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, J M; Böhnlein, A; Bühler, M; Büscher, V; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K; Chan, K M; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clement, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M C; Crepe-Renaudin, S; Cutts, D; Da Motta, H; Das, A; Davies, G; De Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; De, K; Degenhardt, J D; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Déliot, F; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; García, C; García-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Yu; Gillberg, D; Ginther, G; Gollub, N; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, P; Grivaz, J F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutíerrez, G; Gutíerrez, P; Gómez, B; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J M; Kalk, J R; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A I; Kharzheev, Yu M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Klima, B; Kohli, J M; Konrath, J P; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Krop, D; Kryemadhi, A; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Käfer, D; Kühl, T; Lam, D; Lammers, S; Landsberg, G L; Lazoflores, J; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lesne, V; Lewis, P; Li, J; Li, L; Li, Q Z; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Z; Lobo, L; Lobodenko, A; Lokajícek, M; Lounis, A; Love, P; Lubatti, H J; Lynker, M; Lyon, A L; Lévêque, J; Cwiok, M; Maciel, A K A; Madaras, R J; Magass, C; Magerkurth, A; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendes, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miettinen, H; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Monk, J; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Mättig, P; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nomerotski, A; Novaes, S F; Nunnemann, T; Nöding, C; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Oguri, V; Oliveira, N; Onoprienko, D; Oshima, N; Osta, J; Otec, R; Oteroy-Garzon, G J; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Peters, K; Peters, Y; Petroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M E; Pompos, A; Pope, B G; Popov, A V; Potter, C; Prado da Silva, W L; Prosper, H B; Protopopescu, S D; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Rani, K J; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F K; Robinson, S; Rodrigues, R F; Royon, C; Rubinov, P; Ruchti, R; Wang, M H L; Sajot, G; Sanders, M P; Santoro, A F S; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schmitt, C; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Sen-Gupta, S; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Shpakov, D; Siccardi, V; Sidwell, R A; Simák, V; Sirotenko, V I; Skubic, P L; Slattery, P F; Smirnov, D; Smith, R P; Snow, G R; Snow, J; Snyder, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, M; Strom, D; Strovink, M; Ströhmer, R; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Sánchez-Hernández, A; Söldner-Rembold, S; Talby, M; Tamburello, P; Tanasijczuk, A; Taylor, W; Telford, P; Temple, J; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Tomoto, M; Toole, T; Torchiani, I; Trefzger, T; Trincaz-Duvoid, S; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; Van Kooten, R; Van Leeuwen, W M; Van den Berg, P J; Varelas, N; Varnes, E W; Vartapetian, A H; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Séguier, F; Vint, P; Vlimant, J R; Von Törne, E; Voutilainen, M; Vreeswijk, M; Wahl, H D; Walder, J; Wang, L; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Weerts, H; Wenger, A; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, C; Yu, J; Yurkewicz, A; Zatserklyaniy, A; Zeitnitz, C; Zhang, D; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G; de Jong, P; van Eijk, B; Åsman, B

    2007-01-01

    We report a measurement of the branching fraction Br(Bs -> Ds(*) Ds(*)) using a data sample corresponding to 1.3 fb^{-1} of integrated luminosity collected by the D0 experiment in 2002-2006 during Run II of the Fermilab Tevatron Collider. One Ds(*) meson was partially reconstructed in the decay Ds -> phi mu nu, and the other Ds(*) meson was identified using the decay Ds -> phi pi where no attempt was made to distinguish Ds and Ds* states. The resulting measurement is Br(Bs -> Ds(*) Ds(*)) = 0.039 +0.019 -0.017 (stat) +0.016 -0.015 (syst). This was subsequently used to estimate the width difference Delta Gamma^{CP}_s in the Bs-Bsbar system: Delta Gamma^{CP}_s / Gamma_s = 0.079 +0.038 -0.035 (stat) +0.031 -0.030 (syst).

  13. Wavelength-shifting fiber readout of LaCl3 and LaBr3 scintillators

    Science.gov (United States)

    Case, Gary L.; Cherry, Michael L.; Stacy, J. Gregory; Welch, Christopher E.

    2005-08-01

    Inorganic scintillators such as NaI(Tl) and CsI(Na) have been used extensively in hard x-ray and low-energy gamma-ray imaging systems. Recently, a new generation of scintillators has been developed with properties that could greatly enhance the performance of such imaging systems. In particular, the lanthanum halides show great promise with increased light yield and peak emission at shorter wavelengths compared to NaI or CsI. Since these scintillators emit at relatively short wavelengths, wavelength-shifting fibers can be used which re-emit at wavelengths around 420 nm, providing a good match to bialkali photocathode response. Multi-anode photomultiplier tubes can be used to read out individual fibers from orthogonal layers to provide x-y position information, while energy measurements can be made by large area photomultiplier tubes. Such an arrangement potentially provides improved overall position and energy resolution and lower thresholds compared to imaging systems configured as standard NaI or CsI gamma cameras. We present measurements of the energy resolution obtained from lanthanum chloride (LaCl3) and lanthanum bromide (LaBr3) scintillators viewed both perpendicular to the axis and down the length of square multi-clad wavelength-shifting fibers. These results are compared to a standard NaI detector with wavelength-shifting fibers. The implications of these results for gamma-ray imaging will then be discussed.

  14. Standardization of a technique for BrIDA cholescintigraphy.

    Science.gov (United States)

    Patankar, R; Ozmen, M M; Aldous, A; Khader, Z; Fleming, J S; Johnson, C D

    1996-08-01

    Calculation of ejection fraction by cholescintigraphy is a well-established technique to quantify motor function of the gallbladder. All previous cholescintigraphic studies of gallbladder emptying have exclusively used the anterior projection for gallbladder visualization. This may lead to inaccuracies because attenuation of gamma rays may vary depending on the state of gallbladder filling and body habitus. The use of geometric means may prevent these errors. In this study, 7 health volunteers were examined after the administration of 150 MBq 99Tcm-bromotrimethyl-IDA (99Tcm-BrIDA) without any stimulus and 9 volunteers ingested a maxied, fatty meal 35-40 min after BrIDA injection. Imaging was done using a dualheaded camera in a dynamic study of 140 one-minute frames. A plateau of activity was reached between 70 and 90 min post-injection of BrIDA and between 55-60% of maximal counts were achieved in the gallbladder region of interest (ROI) between 35 and 40 min. Significant emptying was seen in all nine subjects after the meal. No significant difference in ejection fraction was seen between the anterior projection and the geometric mean of the data from the anterier and posterior projections. The slope of the gallbladder filling curve from the anterior camera data was different from that obtained from the geometric mean, but the correlation coefficient was not significantly different. In conclusion, adequate counts are achieved in the gallbladder ROI 35-40 min after BrIDA injection, when the stimulus can be administered to study gallbladder emptying. There is no advantage to imaging in the anterior and posterior projections and data obtained from the anterior projection alone are adequate for gallbladder emptying studies.

  15. Optimized Control Rods of the BR2 Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kalcheva, Silva; Koonen, E.

    2007-09-15

    At the present time the BR-2 reactor uses control elements with cadmium as neutron absorbing part. The lower section of the control element is a beryllium assembly cooled by light water. Due to the burn up of the lower end of the cadmium section during the reactor operation, the presently used rods for reactivity control of the BR-2 reactor have to be replaced by new ones. Considered are various types Control Rods with full active part of the following materials: cadmium (Cd), hafnium (Hf), europium oxide (Eu2O3) and gadolinium (Gd2O3). Options to decrease the burn up of the control rod material in the hot spot, such as use of stainless steel in the lower active part of the Control Rod are discussed. Comparison with the characteristics of the presently used Control Rods types is performed. The changing of the characteristics of different types Control Rods and the perturbation effects on the reactor neutronics during the BR-2 fuel cycle are investigated. The burn up of the Control Rod absorbing material, total and differential control rods worth, macroscopic and effective microscopic absorption cross sections, fuel and reactivity evolution are evaluated during approximately 30 operating cycles.

  16. Bréal, un antinaturalisme d’inspiration humboldtienne

    Directory of Open Access Journals (Sweden)

    Babu Jean-Philippe

    2014-07-01

    Full Text Available Dans De la forme et de la fonction des mots, Bréal formulait, dès 1866, outre une critique générale du formalisme de la philologie comparative depuis Bopp, une thèse radicalement opposée à l’orientation naturaliste de l’évolutionnisme linguistique de Schleicher. Cette thèse, que nous prendrons le risque de définir comme thèse du primat de la fonction sur la forme linguistique, est au coeur de ce programme de linguistique générale pour lequel Bréal allait forger, quelques années plus tard, le mot de sémantique. Fortement marqué par la notion humboldtienne d’innere Sprachform, Bréal, contrairement à Saussure, n'abandonnera jamais le changement linguistique au hasard de l'histoire et maintiendra l'intelligence comme premier moteur des langues, quitte à poser la nécessité de repenser cette intelligence.

  17. ReBr(CO)5-Catalyzed Knoevenagel Condensation

    Institute of Scientific and Technical Information of China (English)

    ZUO Wei-xiong; HUA Rui-mao; SUN Hong-bin

    2004-01-01

    Knoevenagel condensations are especially important reactions for the synthesis of alkene compounds having electron-withdrawing groups such as COR,CN,COOR,NO2 etc. Recently,transition metal hydride ruthenium1, hydride and polyhydride rhenium2, and polyhydride iridium complexes have been found to be the efficient catalysts for Knoevenagle condensation. However the mentioned-above transition metal hydride complexes are not easily prepared. In addition, all of them are oxygen and H2O-sensitive, unstable compands. Therefor the catalytic reactions are required to be carried out under an inert atmosphere, and using the prepurified reagent.In the paper, We wish to report the development of Knoevenagel condensation catalyzed by ReBr(CO)5 under an air atmosphere in the absence of solvent.All the experiments were carried out under 1atm, without solvent.The resuIts of the representative Knoevenagel condensations are summarized in Table 1.The Knoevenagel reaction with diethyl malonate can be catalyzed by ReBr(CO)5, while the present Knoevenagel reactions catalyzed by transition metal have at least one cyano group in active methylene compouds.A propose mechanism for present catalytic coupling dehydration reactions is also illustrated in the paper.Briefly, this paper reports the ReBr(CO)5-catalyzed Knoevenagel reaction. The reaction is a new method for the Konevenagel condensation.

  18. Electrical conductivity studies on CuBr containing Al2O3 particles

    Science.gov (United States)

    Dubec, P. M.; Wagner, J. B., Jr.

    1984-01-01

    The conductivity of CuBr was studied and the role of a second phase, Al2O3, dispersed in CuBr was tested. CuBr melts at 493 C and exhibits three phases in the solid state. CuBr is a good ionic conductor with a transport number for copper ions of virtually unity with weighed proportions of the appropriate chemicals used. The CuBr materials were heated above melting point of CuBr, and the samples were sandwiched between copper electrodes. The ac conductivity, was determined at 1 kHz between 25 and 440 C depending on the sample. It was shown that at low temperatures, the conductivity for CuBr (Al2O3) increased by as much as 100, whereas in the beta phase the conductivity of CuBr containing Al2O3 decreased. The electrical conductivity studies are in agreement with earlier data.

  19. Combined measurements of the Higgs boson production and decay rates in $H\\to ZZ^*\\to 4\\ell$ and $H\\to\\gamma\\gamma$ final states using $pp$ collision data at $\\sqrt{s}=$ 13 TeV in the ATLAS experiment

    CERN Document Server

    The ATLAS collaboration

    2016-01-01

    This note presents combined measurements based on Higgs boson production cross sections and branching ratios using more than 13.3 fb$^{-1}$ of proton-proton collision data recorded by the ATLAS experiment at the LHC at $\\sqrt{s}=$ 13 TeV. The combination is based on the analyses of the $H\\to\\gamma\\gamma$ and $H\\to ZZ^*\\to 4\\ell$ decay channels. Results are derived for these two decay modes and five sets of production processes for a Higgs boson rapidity $|y_H| < 2.5$ and for a Higgs boson mass of $125.09 \\pm 0.21{\\rm (stat)} \\pm 0.11{\\rm (syst)}$ GeV. The global signal strength, defined as the ratio in the full phase space (including $|y_H| \\geq 2.5$) between the observed total signal yield and the Standard Model expectation, is measured to be $\\mu = 1.13\\,^{+0.18}_{-0.17}$. The cross section of $pp \\to H + X$ in the full phase space is determined from fiducial cross section measurements to be $59.0^{+9.7}_{-9.2} ~(\\mathrm{stat.})~ ^{+4.4}_{-3.5} (\\mathrm{syst.})$ pb, to be compared with the Standard Model...

  20. Site selective excitation spectroscopy of CsCdBr sub 3 :U sup 3 sup +

    CERN Document Server

    Yin Min

    2002-01-01

    The CsCdBr sub 3 :U sup 3 sup + crystal was grown by the Bridgman technique from the starting materials CsBr, CdBr sub 2 and UBr sub 4. X-ray check showed that the sample crystallized in the CsNiBr sub 3 structure. Under selective excitation at low temperature, the emission spectra and the fluorescence decay curve were measured and discussed

  1. Phasons modulate the atomic Debye-Waller factors in incommensurate structures: Experimental evidence in ThBr[sub 4] at 55 K

    Energy Technology Data Exchange (ETDEWEB)

    Madariaga, G. (Dept. de Fisica de la Materia Condensada, Facultad de Ciencias, Univ. del Pais Vasco, Bilbao (Spain)); Perez-Mato, J.M. (Dept. de Fisica de la Materia Condensada, Facultad de Ciencias, Univ. del Pais Vasco, Bilbao (Spain)); Aramburu, I. (Dept. de Fisica de la Materia Condensada, Facultad de Ciencias, Univ. del Pais Vasco, Bilbao (Spain))

    1993-04-01

    The incommensurate displacive structure of [beta]-ThBr[sub 4] at 55 K has been determined from a neutron diffraction data set including main reflections and first-order satellites. The superspace group is Psub(s anti 1 s1)sup(I4[sub 1]/amd). Final agreement factors are 0.0193, 0.0186 and 0.045 for all, main and satellite reflections, respectively. It is shown that the effect of phasons on the atomic Debye-Waller factors can be quantified by two additional structural parameters: The modulus [beta][sub 11,2][sup Br] and the phase [chi][sub 11,2][sup Br] of a second harmonic that spatially modulates the temperature factors of Br atoms. Results are in good agreement, within the resolution of the experimental data, with the theoretically expected value for [chi][sub 11,2][sup Br]. Crystal data for the average structure: M[sub r]=551.65, tetragonal, I4[sub 1]/amd, a=8.919(1), c=7.902(1) A, V=628.6(2) A[sup 3], Z=4, D[sub x]=5.82 Mg m[sup -3], [lambda]=0.84 A, wavevector q=0.32c*. (orig.).

  2. Ustioni da fuoco / Burn injuries / Les brûlures

    Directory of Open Access Journals (Sweden)

    Liliana Copertino

    2008-04-01

    Full Text Available Severe burn injuries require high specialistic treatment. Burn injuries are common in disasters and war scenarios, so war medicine has been fundamental to improve treatment protocols for burn patients..Burn injuries are classified according to the etiopathogenetic agent (physical, chemical or radiation, that determines different anatomoisthologic aspects.An estimation of the depth and extension are fundamental for defining the gravity of the burn. Critical burn patients have to be transported in specialistic Centers. There they are treated by multispecialistic teams from the resuscitation phase to the reconstructive surgery and specialist rehabilitation.. This process can continue for two years with the objective to return patients to a quiet normal life. Les brûlures sont des lésions traumatiques qui requièrent un traitement spécialisé. Lors de catastrophes et de guerres, les brûlures sont des lésions très fréquentes et la médecine de guerre a contribué à faire avancer la science de manière importante, dans le traitement de cette pathologie.Les brûlures sont classées en fonction de l'agent étiopathogénique (agents physiques, chimiques ou radiations dont le mécanisme d'action qui provoque la lésion cause des aspects anatomohistologiques caractéristiques.Pour définir la sévérité d'une brûlure, il est aussi fondamental d'éstimer l'extension de la surface corporelle et la profondeur de l'épiderme, et éventuellement du derme, atteints. Les patients gravement brûlés doivent être hospitalisés dans des Centres Spécialisés où des équipes multispécialistes les suivent de la phase initiale de la réanimation aux phases de chirurgie reconstructive et au processus de réhabilitation. Ces dernières phases peuvent se prolonger pendant les deux années suivant le traumatisme avant qu'une réintégration dans une vie sociale acceptable ne puisse être faite.

  3. 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

    2013-02-01

    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 water and wastewater chlorination.

  4. AlNbBr{sub 8} - preparation, crystal structure, and vapor pressure studies

    Energy Technology Data Exchange (ETDEWEB)

    Rogachev, Alexander V.; Zelenina, Ludmila N.; Chusova, Tamara P.; Virovets, Alexander V. [Nikolaev Institute of Inorganic Chemistry, Russian Academy of Sciences, Siberian Branch, pr. Lavrentyeva 3, 630090, Novosibirsk (Russian Federation); Sokolov, Maxim N. [Nikolaev Institute of Inorganic Chemistry, Russian Academy of Sciences, Siberian Branch, pr. Lavrentyeva 3, 630090, Novosibirsk (Russian Federation); Novosibirsk State University, ul. Pirogova 2, 630090, Novosibirsk (Russian Federation)

    2016-07-15

    The ternary niobium compound AlNbBr{sub 8} (1) was synthesized by degradation of NbS{sub 2}Br{sub 2} in AlBr{sub 3} and from elements. Crystal structure and thermodynamic properties of sublimation process were studied. (Copyright copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Communication: Interaction of BrO radical with the surface of water

    Science.gov (United States)

    Zhu, Chongqin; Gao, Yurui; Zhong, Jie; Huang, Yingying; Francisco, Joseph S.; Zeng, Xiao Cheng

    2016-12-01

    Solvation of a BrO radical in a slab of water is investigated using adaptive buffered force quantum mechanics/molecular mechanics (QM/MM) dynamics simulations. The simulation results show that the BrO radical exhibits preference towards the water surface with respect to the interior region of the water slab, despite BrO's high affinity to water. Another important finding is the weakening of (BrO)Br⋯O(water) interaction at the water surface due to competitive interactions between (BrO)Br⋯O(water) and (water)H⋯O(water). As such, the BrO-water slab interaction is dominated by (BrO)O⋯H(water) interaction, contrary to that in the gas phase, suggesting that the reactive site for the BrO radical at the air/water surface is more likely the Br site. The conclusion from this study can offer deeper insight into the reactivity of the BrO radical at the air/water interface, with regard to atmospheric implications.

  6. Kuidas mõõta brändi mõjukust! / Lauri Talve

    Index Scriptorium Estoniae

    Talve, Lauri

    2002-01-01

    Brändi väärtuse hindamise süsteem ning selle 4 fundamentaalset koostisosa; 9 võimalikku brändimustrit brändi hetkeolukorra hindamiseks. Artikli aluseks on peatükk autori ülikooli lõputööst. Skeemid

  7. File list: His.Brs.20.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Brs.20.AllAg.SK-BR-3 hg19 Histone Breast SK-BR-3 SRX750665,SRX750660,SRX469107,...SRX469108 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.Brs.20.AllAg.SK-BR-3.bed ...

  8. File list: Oth.Brs.10.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Brs.10.AllAg.SK-BR-3 hg19 TFs and others Breast SK-BR-3 SRX155755,SRX128102,SRX...155754 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Brs.10.AllAg.SK-BR-3.bed ...

  9. File list: Oth.Brs.20.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Brs.20.AllAg.SK-BR-3 hg19 TFs and others Breast SK-BR-3 SRX155755,SRX128102,SRX...155754 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Brs.20.AllAg.SK-BR-3.bed ...

  10. File list: His.Brs.05.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Brs.05.AllAg.SK-BR-3 hg19 Histone Breast SK-BR-3 SRX750660,SRX750665,SRX469108,...SRX469107 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.Brs.05.AllAg.SK-BR-3.bed ...

  11. File list: Oth.Brs.50.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Brs.50.AllAg.SK-BR-3 hg19 TFs and others Breast SK-BR-3 SRX128102,SRX155755,SRX...155754 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Brs.50.AllAg.SK-BR-3.bed ...

  12. File list: Oth.Brs.05.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Brs.05.AllAg.SK-BR-3 hg19 TFs and others Breast SK-BR-3 SRX155754,SRX155755,SRX...128102 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Brs.05.AllAg.SK-BR-3.bed ...

  13. File list: His.Brs.10.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Brs.10.AllAg.SK-BR-3 hg19 Histone Breast SK-BR-3 SRX750660,SRX750665,SRX469108,...SRX469107 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.Brs.10.AllAg.SK-BR-3.bed ...

  14. "Brücke dreht sich um!". A Deconstructionist Reading of Kafka's "Die Brücke"

    Directory of Open Access Journals (Sweden)

    Eva Hoffmann

    2014-12-01

    Full Text Available Franz Kafka's (1883-1924 "Die Brücke" is one of the less well-known texts by one of the most prolific authors of literary modernity. However, this short prose text embodies prevalent questions of literary modernity and philosophy as it reflects the crisis of language in regard of identity, communication, and literary production. Placed in the context of fin-de-siècle's discourse of language crisis, this article provides a dialogue between Kafka's "Die Brücke" and Hannah Arendt's (1906-1975 philosophy of thinking and speaking in The Life of the Mind. Contrary to Arendt's understanding of the metaphor as "a carrying over" between the mental activities of the solitude thinker and a reconciliation with the pluralistic world shared with others, this article argues for a deconstructionist reading of "Die Brücke" as a tool to reevaluate Arendt's notion of a shared human experience ensured through language and illustrates the advantages of poetic texts within philosophical discourses.

  15. Semi-Classical Dynamics Studies of the Photodissociation of ICN^{-} and BrCN^{-}

    Science.gov (United States)

    Opoku-Agyeman, Bernice; McCoy, Anne B.

    2017-06-01

    We present the results of surface hopping studies of the photodissociation of ICN^{-} and BrCN^{-} following UV and visible excitations to states that can dissociate to X^{-} + CN or X^{*} + CN^{-} (X = I or Br). Based on previous quantum dynamics studies carried out on the anions, the electronic states that are accessed by the initial UV or visible excitation were found to be coupled, and both photoproducts were observed in the dissociation process. The calculated branching ratios indicated stronger non-adiabatic interactions between the adiabatic electronic states in BrCN^{-} than in ICN^{-}. In this work, we employ Tully's surface hopping algorithm implemented in classical dynamics simulations to investigate the fragmentation processes of these anions. We calculate the branching ratios and the partitioning of the energies among the various degrees of freedom during the dynamics. The results of the surface hopping algorithm are then compared to the reported quantum dynamics results after which the surface hopping approach can then be applied to investigate the dynamics of argon clusters of the ICN^{-} and BrCN^{-}. In addition to comparison between the quantum and classical dynamics calculations, preliminary results for the semi-classical calculations on the ICN^{-} show that during the dissociation process, some of the anions live longer than others. Once the anions are solvated, we expect the presence of the argon atoms to stabilize the complexes as reported in previous work, resulting in longer lifetimes. Since experimental studies carried out on the solvated anions show the existence of recombined products even for clusters as small as ICN^{-}(Ar) or ICN^{-}(Ar)_2, when the clusters are initially excited with visible or UV radiations, respectively,^{b c} the observations of these long-lived anions provide a step towards understanding the dynamics processes that lead to the recombined products in the clusters. B. Opoku-Agyeman, A. S. Case, J. H. Lehman, W

  16. Characterisation of vertical BrO distribution during events of enhanced tropospheric BrO in Antarctica, from combined remote and in-situ measurements

    OpenAIRE

    Roscoe, H. K.; Brough, N.; Jones, A. E.; Wittrock, F.; Richter, A.; Van Roozendael, M.; Hendrick, F.

    2014-01-01

    Tropospheric BrO was measured by a ground-based remote-sensing spectrometer at Halley in Antarctica in spring 2007, and BrO was measured by satellite-borne remote-sensing spectrometers using similar spectral regions and similar Differential Optical Absorption Spectroscopy (DOAS) analyses. Near-surface BrO was simultaneously measured in situ at Halley by Chemical Ionisation Mass Spectrometer (CIMS), and in an earlier year near-surface BrO was measured at Halley over a long path by a ground-bas...

  17. Azimuthal structure of charged particle emission in 28Si-Ag/Br interaction at 14.5A GeV and 32S-Ag/Br interaction at 200A GeV

    Science.gov (United States)

    Mali, Provash; Mukhopadhyay, Amitabha; Sarkar, Soumya; Singh, Gurmukh

    2014-05-01

    Presence of unusual azimuthal structures in the particle emission data obtained from the 28Si-Ag/Br interaction at 14.5A GeV and from the 32S-Ag/Br interaction at 200A GeV, are investigated in the framework of the Cherenkov gluon emission and/or Mach shock wave formation in nuclear/partonic medium. Nuclear photographic emulsion technique is used to collect the experimental data. The experiment is compared with the predictions of two simulations, namely (i) the Relativistic Quantum Molecular Dynamics (RQMD) and (ii) the Ultra-relativistic Quantum Molecular Dynamics (UrQMD). A charge reassignment algorithm is implemented over the outputs of the simulations to mimic the Bose-Einstein correlation (BEC) effect. Our analysis confirms presence of jet-like structures in both experiments beyond statistical noise. Such structures are more pronounced in the 32S data than in the 28Si data.

  18. Modifying CH3NH3PbBr3 nanocrystals with arylamines

    Science.gov (United States)

    Zhu, Ruimin; Liu, Heyuan; Shen, Li; Sun, Dejun; Li, Xiyou

    2017-04-01

    Chemically decorating CH3NH3PbBr3 with a group of para-substituted arylamine (R-An) was investigated, where R ranges from electron-withdrawing trifluoromethoxy(-CF3O), to hydrogen or electron-donating ethoxy (-EtO). Different ratios of R-An ammonium bromide and methylammonium bromide (MA) (R-An/MA=3/7, 4/6, 5/5, 6/4 and 7/3) were tested. XRD patterns revealed that the perovskite nanocomposite were cubic with good crystallinity. TEM and photoluminescence suggested that the perovskite nanocrystals were composed of 2D layered and 3D bulk structures. 1H NMR and TGA experiments revealed that the non-substituted aniline can readily adsorb to the surface of perovskite at any ratios between R-An and MA. But an EtOAn/MA ratio ≥1 is needed to anchor the EOAn molecules on the surface of perovskite. For the arylamine with the electron-withdrawing -CF3O group, it cannot adsorb to the surface of the perovskite at any concentrations. This result reveals that both steric hindrance and alkalinity can affect the anchoring of arylamine on the surface of CH3NH3PbBr3 perovskite. I-V curves of the perovskite nanocrystal films prepared by spin coating suggest that proper surface modification can increase the conductivity significantly.

  19. Synthesis and Crystal Structure of [Cu(acac)(Hdmpz)3]Br·EtOH

    Institute of Scientific and Technical Information of China (English)

    LIU Jiu-Hui; ZHANG Quan-Zheng; HE Xiang; YU Ya-Qing; LU Can-Zhong

    2005-01-01

    The complex [Cu(C5H7O2)(C5H8N2)3]Br. C2H5OH was obtained from a reaction of CuBr, acac, and Hdmpz (Hdmpz = 3, 5-dimethylpyrazole) in a mixed solution of ethanol, ether and water. The crystal belongs to monoclinic system, space group P21/n with a = 8.101 (5), b = 19.264(10), c = 17.19(3) (A), β = 95.54(2)°, V = 2670(5) (A)3, Z = 4, Mr = 577.03, Dc = 1.435 g/cm3, F(000) = 1196, μ = 2.348 mm-1, R = 0.0500 and wR = 0.1188 for 5361 observed reflections (I > 2σ(Ⅰ)). The Cu(Ⅱ) ion is coordinated by three Hdmpz and one acac to form a distorted square-pyramid. The complex contains an ethanol molecule and a bromide anion outside acting as the counter ion.

  20. <i>Femeniasia, novus genus Carduearumi>

    Directory of Open Access Journals (Sweden)

    Susanna de la Serna, Alfonso

    1988-01-01

    Full Text Available The systematic position of <i>Centaurea balearicai> Rodríguez Femenias (<i>Asteraceae-Cardueae> is studied. A detailed analysis or its anatomy, with special reference to the carpology, forces the author lo reject its inclusion in the genus <i>Centaurea> or in any other genus or the tribe. A new genus, <i>Femeniasia> Susanna. is hence described, and the new nomenclatural combinari en <i>Femeniasia balearicai> (Rodríguez Femenías Susanna is proposed. The relationship or <i>Femeniasia> and the other genera of the tribe is discussed; the author concludes that <i>Femeniasia> is a quite isolated genus in the <i>Cardueae-Carduinae> .<br>>[ca] Estudi de la posició sistemàtica de <i>Centaurea balearicai> Rodríguez Femenías (<i>Asteraceae-Cardueae> . De l'anàlisi minuciosa de la seva anatomia, especialment de les seves cípseles, resulta que l'esmentada espècie no és cap <i>Centaurea>; tampoc pot ésser inclosa en cap del altres gèneres de la tribu. En conseqüència, hom descriu un nou gènere, <i>Femeniasia> Susanna, i proposa la combinació <i>Femeniasia balearicai> (Rodríguez Femenías Susanna. Son analitzades les possibles relacions de parentiu amb d'altres gèneres del grup i l'autor arriba a la conclusió que <i>Femeniasia> és un gènere clarament isolat entre les <i>Cardueae-Carduinae>.

  1. Identification of a BrOOO- intermediate species in the ozonolysis of bromide at the liquid/vapor interface from liquid jet XPS

    Science.gov (United States)

    Chen, Shuzhen; Artiglia, Luca; Orlando, Fabrizio; Corral-Arroyo, Pablo; Edebeli, Jacinta; Ammann, Markus

    2017-04-01

    Oxidation of bromide by gas phase ozone (O3) in the absence of photochemistry is believed to be one of the important dark reactions to produce HOBr as the starting point of the multiphase cycling reaction mechanisms that release bromide out of sea water, sea spray or marine aerosols from aqueous solution that later drive O3 depleting chemistry in the troposphere [1]. The reaction of bromide with O3 occurs through an acid catalyzed mechanism involving a BrOOO- complex as an intermediate [2]. Slow oxidation of bromide by O3 in the bulk aqueous phase is of limited relevance; previous kinetic experiments have suspected the reaction to be enhanced at the surface of aqueous solutions. Thus, identifying BrOOO- at the interface would be a major step to understanding the multiphase oxidation of bromide with O3. Here, we provide a direct experimental evidence for the formation of a BrOOO- reaction intermediate at the surface by investigating the reaction of aqueous solutions NaBr with gas phase O3 after millisecond time scale exposure using the surface sensitive in situ liquid jet X-ray photoelectron spectroscopy (XPS) at the Swiss Light Source (SLS). We acquired Br 3d core level spectra of 0.125 M NaBr solution in presence and absence of ozone in the gas phase. We found a new feature with a peak position shifted towards higher binding energy (by ˜0.7 eV) compared to Br-, which was clearly different from the Br 3d core levels spectra of hypobromite and bromate measured with reference solutions. Our results suggest the appearance of the formation of the BrOOO- reaction intermediate as a new component, in agreement with theoretical calculations of the Br- ozonolysis mechanism [3]. Additionally, by varying the photoelectron kinetic energy and thus probe depth via variation of the probing photon energy, the new feature appears to be present near the liquid/vapor interface. Besides, kinetic experiments for the reaction of O3 with bromide are ongoing to investigate the dependence

  2. Thermodynamics limits the reactivity of BrHg radical with volatile organic compounds

    Science.gov (United States)

    Dibble, Theodore S.; Schwid, Abraham C.

    2016-08-01

    Mercury emissions to the atmosphere primarily consist of Hg(0), which tends not to enter ecosystems until it is oxidized. Atomic bromine initiates oxidation of Hg(0) via the BrHg intermediate, but the further reactions of BrHg are just beginning to be explored. Here we use quantum chemistry to determine that hydrogen abstraction from hydrocarbons by BrHg is so endothermic as to be irrelevant. Bonds between BrHg and carbon atoms are so weak that BrHg addition to carbon-carbon double bonds atoms will be somewhat ineffective in leading to further reactions.

  3. Improved Growth Methods for LaBr3 Scintillation Radiation Detectors

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas S

    2011-05-01

    The objective is to develop advanced materials for deployment as high-resolution gamma ray detectors. Both LaBr3 and CeBr3 are advanced scintillation materials, and will be studied in this research. Prototype devices, in collaboration Sandia National Laboratories, will be demonstrated along with recommendations for mass production and deployment. It is anticipated that improved methods of crystal growth will yield larger single crystals of LaBr3 for deployable room-temperature operated gamma radiation spectrometers. The growth methods will be characterized. The LaBr3 and CeBr3 scintillation crystals will be characterized for light yield, spectral resolution, and for hardness.

  4. A Discharge-Excited SrBr2 Vapour Laser

    Institute of Scientific and Technical Information of China (English)

    潘佰良; 姚志欣; 陈钢

    2002-01-01

    A new-style discharge tube for a metal vapour laser has been designed and built. SrBr2 was successfullyused to replace the metal strontium as a working medium. Multi-line laser oscillations from resonance tometastable transition of strontium atoms (6.45um), ions (1.03um/1.O9um) and from strontium ion recombi-nation (416.2nm/430.5nm) have been obtained through longitudinal pulsed discharge. The problem of an in-compatibility reaction between metallic strontium and the discharge tube in the strontium vapour laser has beensolved. Some proposals are presented for further developments of strontium halide lasers.

  5. Brüssel enne Moskvat / Markus Meckel, Matthias Wissmann

    Index Scriptorium Estoniae

    Meckel, Markus

    2005-01-01

    Saksa liiduparlamendi sotsiaaldemokraatide fraktsiooni liikme Markus Meckeli ja Saksa liiduparlamendi Euroopa komisjoni esimehe Matthias Wissmanni avaldus, milles nad kutsuvad tunnistama Balti riikide ajalugu ja korraldama päev enne Moskvas toimuvat Teise maailmasõja lõppu tähistavat üritust Brüsselis sõja lõpu 60. aastapäeva mälestusürituse. Artikkel ilmus samaaegselt ajalehtedes International Herald Tribune, Die Welt, Die Presse, Le Figaro, Gazeta Wyborcza, Lietuvas rytas, Diena

  6. PHARMACOGNOSTIC AND PHYTOCHEMICAL STUDY OF CHLOROPHYTUM LAXUM R. BR.

    Directory of Open Access Journals (Sweden)

    Patil Vishal Narayan

    2011-06-01

    Full Text Available Chlorophytum laxum R. Br. belongs to family Liliaceae and is being used in the indigenous systems of medicine as a galactogogue and aphrodisiac. It is being sold in the market under the common name “safed musali”. The white tuberous roots of this plant are the medicinally useful parts. The tuberous roots of other species of Chlorophytum, Asparagus, Bombax and Orchids are also sometimes called safed musali leading to confusion. In order to ensure correct botanical standardization, the detailed pharmacognostic study on tuberous roots of Chlorophytum laxum has been carried out in this study.

  7. Refurbishment of BR2 (Phases 4 and 5)

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P.; Dekeyser, J.; Van Der Auwera, J

    1998-07-01

    The BR2 is a materials testing reactor and is 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. In phase 4 of the refurbishment programme, various activities were performed to allow reactor start-up. In phase 5, remaining refurbishment works were carried out as well as the extra studies and upgradings required by the licensing authorities. Major achievements in 1997 are described and discussed.

  8. Synthesis of cellulose dehydroabietate in ionic liquid [bmim]Br.

    Science.gov (United States)

    Xu, Xuetang; Duan, Wengui; Huang, Mei; Li, Guanghua

    2011-09-27

    A new type of cellulose derivative, cellulose dehydroabietate (CDA), was synthesized by the O-acylation reaction of cellulose with dehydroabietic acid chloride (DHAC) using ionic liquid 1-butyl-3-methylimidazolium bromide ([bmim]Br) as a solvent and 4-dimethyl-aminopyridine (DMAP) as a catalyst. The resulting CDA was characterized by means of FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and elemental analysis. Also, some properties of CDA were determined. These results showed that CDA has better solubility, water-repellency, and resistance to acids and bases than raw cellulose, and these properties increase with the DS of CDA.

  9. Brüssel enne Moskvat / Markus Meckel, Matthias Wissmann

    Index Scriptorium Estoniae

    Meckel, Markus

    2005-01-01

    Saksa liiduparlamendi sotsiaaldemokraatide fraktsiooni liikme Markus Meckeli ja Saksa liiduparlamendi Euroopa komisjoni esimehe Matthias Wissmanni avaldus, milles nad kutsuvad tunnistama Balti riikide ajalugu ja korraldama päev enne Moskvas toimuvat Teise maailmasõja lõppu tähistavat üritust Brüsselis sõja lõpu 60. aastapäeva mälestusürituse. Artikkel ilmus samaaegselt ajalehtedes International Herald Tribune, Die Welt, Die Presse, Le Figaro, Gazeta Wyborcza, Lietuvas rytas, Diena

  10. Measurement of the Ratio BR(B- --> D*0 K-)/BR(B- --> D*0 pi-) and of the CP Asymmetry of B- --> D*0(CP+) K- Decays

    CERN Document Server

    Aubert, B; Boutigny, D; Couderc, F; Gaillard, J M; Hicheur, A; Karyotakis, Yu; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Shelkov, V G; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Çuhadar-Dönszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Foulkes, S D; Gary, J W; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Lockman, W S; Nesom, G; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Smith, J G; Zhang, J; Zhang, L; Chen, A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q L; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, Klaus R; Schwierz, R; Spaan, B; Sundermann, J E; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Schrenk, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Lavin, D; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, Erwin; Gamet, R; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Cowan, G; Flack, R L; Flächer, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Fabozzi, F; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Malcles, J; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Anulli, F; Biasini, M; Peruzzi, I M; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martínez-Vidal, F; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Geddes, N I; Gopal, G P; Olaiya, E O; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Claus, R; Convery, M R; Cristinziani, M; De Nardo, Gallieno; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Elsen, E E; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Vavra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, Patricia R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Sobie, R J; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mihályi, A; Mohapatra, A K; Pan, Y; Prepost, R; Rubin, A E; Sekula, S J; Tan, P; Von Wimmersperg-Töller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2004-01-01

    We study the decays B- --> D*0 pi- and B- --> D*0 K-, where the D*0 decays into D0 pi0, with the D0 reconstructed in the CP-even (CP+) eigenstates K- K+ and pi- pi+ and in the (non-CP) channels K- pi+, K- pi+ pi+ pi-, and K- pi+ pi0. Using a sample of about 123 million BBbar pairs, we measure the ratios of decay rates R*(non-CP)=BR(B- --> D*0(non-CP) K-)/BR(B- --> D*0(non-CP) pi-) = 0.0813+-0.0040(stat)+0.0042-0.0031}(syst), and provide the first measurements of R*(CP+)= BR(B- --> D*0(CP+) K-)/BR(B- --> D*0(CP+) pi-) = 0.086+-0.021(stat)+-0. 007(syst), and of the CP asymmetry A*(CP+) = (BR(B- --> D*0(CP+) K-) - BR(B+ --> D*0(CP+) K+))/(BR(B- --> D*0(CP+) K-) + BR(B+ --> D*0(CP+) K+)) = -0.10+-0.23(stat)+0.03-0.04(syst).

  11. Synthesis and Crystal Structure of a Copper(Ⅱ) Complex with a Tab-Tab Disulfide Ligand (Tab-Tab)[CuBr4] (Tab = Trimethylammoniumphenyl-4-thiolate)

    Institute of Scientific and Technical Information of China (English)

    TANG Xiao-Yan; CHEN Jin-Xiang; LANG Jian-Ping

    2006-01-01

    Reaction of CuBr2 with TabHPF6/Et3N in methanol followed by dissolving the resulting precipitate in hydrobromic acid yielded purple blocks of the title complex [Tab-Tab][CuBr4] 1 (C18H26CuBr4N2S2). 1 crystallizes in the monoclinic system, space group P21/n with a = 9.686(3),b = 19.257(5), c = 13.399(4) (A), β= 93.610(9)°, V= 2494.2(13) (A)3, Z= 4, Dc = 1.911 g/cm3, T=193(2) K, Mr = 717.71, F(000) = 1396, μ = 74.58 cm-1, S = 1.126, R = 0.0748 and wR = 0.1736 for 2921 observed reflections with I > 2σ(Ⅰ). The structure of 1 contains a discrete [CuBr4]2- dianion and a [Tab-Tab]2+ dication. In the dianion, the Cu atom is coordinated to four Br atoms forming a distorted tetrahedral coordination geometry. The bromides of the dianion interact with the H atoms of the phenyl and methyl groups of the dications to form a 1D hydrogen-bonded chain.

  12. El género <i>Polygala> (<i>Polygalaceae> en el Mediterráneo Occidental

    Directory of Open Access Journals (Sweden)

    Paiva, Jorge

    1989-06-01

    Full Text Available <i>Polygala> L. comprises about 720 species (400 American, 206 African, 32 European, 70 Asiatic and 12 Australian.The genus is extended all over the world except Polynesia. New Zealand and the polar regions. The 24 Western Mediterranean species of <i>Polygala> belong to three subgenera (5 to the subgen. Chamaebuxus, 1 to the subgen. <i>Brachytropis> and 18 to the subgen. <i>Polygala>. Looking into morphological, caryological, Palynological, anatomical and ontogenic data, subgenus <i>Chamaebuxus> looks more primitive than subgenus <i>Polygala>, and subgenus <i>Brachytropis> is perhaps derived from the former.<br>
    Polygala> es un género con cerca de 720 especies (400 americanas, 206 africanas, 32 europeas, 70 asiáticas y 12 australianas distribuidas por casi lodo el globo excepto Polinesia, Nueva Zelanda y las regiones polares. Las 24 especies de <i>Polygala> confinadas en el Mediterráneo Occidental pertenecen a 3 subgéneros (5 al subgénero <i>Chamaebuxus>, 1 al subgénero <i>Brachytropis> y 18 al subgénero <i>Polygala>. De los datos morfológicos, cariológicos, palinológicos, anatómicos y ontogénicos, se desprende que el subgénero <i>Chamaebuxus> resulta más primitivo que el subgénero <i>Polygala> y que el subgénero <i>Brachytropis> se deriva tal vez del primero de los citados.

  13. New results for the formation of a muoniated radical in the Mu + Br2 system: a van der Waals complex or evidence for vibrational bonding in Br-Mu-Br?

    Science.gov (United States)

    Fleming, Donald G; Cottrell, Stephen P; McKenzie, Iain; Macrae, Roderick M

    2012-08-21

    New evidence is presented for the observation of a muoniated radical in the Mu + Br(2) system, from μSR longitudinal field (LF) repolarisation studies in the gas phase, at Br(2) concentrations of 0.1 bar in a Br(2)/N(2) mixture at 300 K and at 10 bar total pressure. The LF repolarisation curve, up to a field of 4.5 kG, reveals two paramagnetic components, one for the Mu atom, formed promptly during the slowing-down process of the positive muon, with a known Mu hyperfine coupling constant (hfcc) of 4463 MHz, and one for a muoniated radical formed by fast Mu addition. From model fits to the Br(2)/N(2) data, the radical component is found to have an unusually high muon hfcc, assessed to be ∼3300 MHz with an overall error due to systematics expected to exceed 10%. This high muon hfcc is taken as evidence for the observation of either the Br-Mu-Br radical, and hence of vibrational bonding in this H[combining low line]-L[combining low line]-H[combining low line] system, or of a MuBr(2) van der Waals complex formed in the entrance channel. Preliminary ab initio electronic structure calculations suggest the latter is more likely but fully rigorous calculations of the effect of dynamics on the hfcc for either system have yet to be carried out.

  14. Photocatalytic transformations of CCl{sub 3}Br, CBr{sub 3}F, CHCl{sub 2}Br and CH{sub 2}BrCl in aerobic and anaerobic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Calza, P.; Minero, C.; Pelizzetti, E. [Dipartimento di Chimica Analitica, Universita di Torino, 10125 Torino (Italy); Hiskia, A.; Papaconstantinou, E. [Institute of Physical Chemistry, NCSR Demokritos, 15310 Athens (Greece)

    2001-01-01

    Phototransformations of halomethanes containing chlorine and bromine (CCl{sub 3}Br, CHCl{sub 2}Br, CH{sub 2}ClBr) or bromine and fluorine (CBr{sub 3}F) have been investigated under aerobic and anaerobic conditions both in homogeneous system and heterogeneous photocatalysis. For all of those compounds, the complete disappearance of the primary compound and the stoichiometric concentration of halides was achieved. Several halogenated intermediates and oxygenated compounds were identified, so that it was possible to predict the degradation pathways followed by such halomethanes. Whereas the reductive steps are predominant in the initial degradation of CCl{sub 3}Br and CBr{sub 3}F, the oxidative steps are predominant in the initial CH{sub 2}ClBr steps. The two pathways have comparable importance for CHCl{sub 2}Br degradation. Methanol, acting as a hole scavenger, strongly increases the rate of disappearance for CCl{sub 3}Br and CBr{sub 3}F.

  15. The role of orbiting resonances in the vibrational predissociation of Ne-Br{sub 2}(B)

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Vela, A [Instituto de Fisica Fundamental, CSIC, Serrano 123, 28006 Madrid (Spain)], E-mail: garciavela@imaff.cfmac.csic.es

    2009-10-15

    The spectrum of Ne-Br{sub 2}(B,v) orbiting resonances embedded in the continuum of the v=25 vibrational manifold has been studied and compared with the spectrum previously obtained for v=26. The spectra of orbiting resonances are found to be very similar in the two vibrational manifolds, with the resonances located at nearly the same energy positions and with similar widths. The same result was found for the spectra of orbiting resonances of He-I{sub 2}(B,v) for v=59 and 60. This confirms that the nature of the continuum resonances is the same in both van der Waals complexes, and suggests that this type of resonance might be present in other van der Waals rare gas-halogen clusters.

  16. Combustion instability investigations on the BR710 jet engine

    Energy Technology Data Exchange (ETDEWEB)

    Konrad, W.; Brehm, N.; Kameier, F. [BMW Rolls-Royce AeroEngines, Dahlewitz (Germany); Freeman, C. [Rolls-Royce PLC, Derby (United Kingdom). Advanced Propulsion Systems; Day, I.J. [Cambridge Univ. (United Kingdom). Whittle Lab.

    1998-01-01

    During the development of the BR710 jet engine, audible combustor instabilities (termed rumble) occurred. Amplitudes measured with test cell microphones were up to 130 dB at around 100 Hz. Disturbances of this amplitude are clearly undesirable, even if only present during start-up, and a research program was initiated to eliminate the problem. Presented here is the methodical and structured approach used to identify, understand, and remove the instability. Some reference is made to theory, which was used for guidance, but the focus of the work is on the research done to find the cause of the problem and to correct it. The investigation followed two separate, but parallel, paths--one looking in detail at individual components of the engine to identify possible involvement in the instability and the other looking at the pressure signals from various parts of a complete engine to help pinpoint the source of the disturbance. The main cause of the BR710 combustor rumble was found to be a self-excited aerodynamic instability arising from the design of the fuel injector head. In the end, minor modifications lead to spray pattern changes, which greatly reduced the combustor noise. As a result of this work, new recommendation are made for reducing the risk of combustion instabilities in jet engines.

  17. Evidence for shape coexistence in sup 7 sup 7 Br

    CERN Document Server

    Ray, I; Bhattacharya, S; Goswami, A; Muralithar, S; Singh, R P; Bhowmik, R K

    2001-01-01

    The nucleus sup 7 sup 7 Br has been studied in the reaction sup 6 sup 5 Cu( sup 1 sup 6 O, 2p2n) at E=75 MeV. Lifetimes have been measured for several states using the Doppler-shift attenuation technique. The B(E2) values for the inband transitions, deduced from the lifetime results, reflect strong collectivity for both the positive-parity yrast band (band 1) and the ground-state negative-parity band (band 2). States with spin above 17/2 sup + in band 1 are found to have a large average quadrupole deformation of beta sub 2 =0.35. The experimental results for band 2 suggest that the 25/2 sup - and 29/2 sup - states are somewhat more strongly deformed than the lower-spin states. A comparison of the experimental results with particle-rotor-model calculations provides evidence for shape coexistence in sup 7 sup 7 Br, favouring a prolate shape for the g sub 9 sub / sub 2 yrast band and an oblate shape for the lowest negative-parity band.

  18. Procedimientos de nominación en la flora silvestre: <i>agavanzo>, <i>escaramujo>, <i>rosal bravíoi>

    Directory of Open Access Journals (Sweden)

    Molina, Isabel

    2002-12-01

    Full Text Available The author describes a classification of the folk names of the <i>dog rosei> in the Peninsular Spanish Geography. This is a well known shrub in the rural space because of its different employments and applications. The linguistic filiation of lexical variants and geographic distribution is also presented.<br>>En este estudio se presenta una clasificación de los nombres populares del <i>escaramujo> en la geografía española peninsular, arbusto muy conocido en el medio rural por sus variados usos y aplicaciones. Se establece la filiación lingüística de las variantes léxicas y se aclara su distribución geográfica.

  19. A thermodynamic description of the KBr–EuBr{sub 2} system

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Weiping, E-mail: gwp@hzu.edu.cn [Laboratory of Electronic Functional Materials, Huizhou University, Huizhou 516001, Guangdong (China); Gaune-Escard, Marcelle [Ecole Polytechnique, Mecanique Energetique, Technopole De Chateau-Gombert, 5 Rue Enrico Fermi, 13453 Marseille Cedex 13 (France)

    2014-01-25

    Highlights: • CALPHAD method was used to derive thermodynamic parameters of the system. • Heat capacities of K{sub 2}EuBr{sub 4} and KEu{sub 2}Br{sub 5} were fitted to literature data. • Phase diagram of KBr–EuBr{sub 2} was calculated. • More investigations were necessary to check the stability of the compounds. -- Abstract: Critical thermodynamic description on KBr–EuBr{sub 2} system was carried out by CALPHAD method. The thermodynamic parameters of the pure KBr and EuBr{sub 2} compounds were taken from the SGTE recommended database and the authors’ previous assessment, respectively. A two-sublattice ionic solution model for the liquid, denoted as (K{sup +}){sub P}:(Br{sup −}, EuBr{sub 4}{sup -2}, EuBr{sub 2}){sub Q}, was employed to represent phase diagram and enthalpy of mixing data. To reach a self-consistent thermodynamic description for the constituent phases in the system, the experimental heat capacity data of the intermediate compounds K{sub 2}EuBr{sub 4} and KEu{sub 2}Br{sub 5} were evaluated.

  20. Crystal growth and characterization of Eu2+ doped RbCaX3 (X = Cl, Br) scintillators

    Science.gov (United States)

    Rebrova, N. V.; Grippa, A. Yu.; Pushak, A. S.; Gorbacheva, T. E.; Pedash, V. Yu.; Viagin, O. G.; Cherginets, V. L.; Tarasov, V. A.; Vistovskyy, V. V.; Vas'kiv, A. P.; Myagkota, S. V.

    2017-05-01

    The single crystals of RbCa1-yEuyX3 (X = Cl, Br; y = 0.03, 0.05, 0.08) were obtained by the Bridgman-Stockbarger technique. The luminescent and luminescent-kinetic properties of RbCaCl3:5%Eu and RbCaBr3:5%Eu under photo- and X-ray excitation (35-40 keV) at 77 and 293 K were studied. The luminescence spectra of the crystals exhibit one dominant band which corresponds to Eu2+ emission. The scintillation properties of all the grown crystals under 137Cs 662 keV gamma-ray excitation were investigated. The maximal values of relative light output were found for RbCaCl3:8%Eu2+ and RbCaBr3:8%Eu2+ which are approximately equal to 50% and 77% of NaI:Tl with decay time 2.7 and 3.6 μs respectively. The hygroscopicity of the crystals was estimated.

  1. Total Absorption Gamma-Ray Spectroscopy of 87Br, 88Br and 94Rb Beta-Delayed Neutron Emitters

    CERN Document Server

    Valencia, E; Algora, A; Agramunt, J; Rubio, B; Rice, S; Gelletly, W; Regan, P; Zakari-Issoufou, A -A; Fallot, M; Porta, A; Rissanen, J; Eronen, T; Aysto, J; Batist, L; Bowry, M; Bui, V M; Caballero-Folch, R; Cano-Ott, D; Elomaa, V -V; Estevez, E; Farrelly, G F; Garcia, A R; Gomez-Hornillos, B; Gorlychev, V; Hakala, J; Jordan, M D; Jokinen, A; Kolhinen, V S; Kondev, F G; Martinez, T; Mendoza, E; Moore, I; Penttila, H; Podolyak, Zs; Reponen, M; Sonnenschein, V; Sonzogni, A A

    2016-01-01

    We investigate the decay of 87Br, 88Br and 94Rb using total absorption gamma-ray spectroscopy. These important fission products are beta-delayed neutron emitters. Our data show considerable gamma-intensity, so far unobserved in high-resolution gamma-ray spectroscopy, from states at high excitation energy. We also find significant differences with the beta intensity that can be deduced from existing measurements of the beta spectrum. We evaluate the impact of the present data on reactor decay heat using summation calculations. Although the effect is relatively small it helps to reduce the discrepancy between calculations and integral measurements of the photon component for 235U fission at cooling times in the range 1 to 100 s. We also use summation calculations to evaluate the impact of present data on reactor antineutrino spectra. We find a significant effect at antineutrino energies in the range of 5 to 9 MeV. In addition, we observe an unexpected strong probability for gamma emission from neutron unbound s...

  2. Theoretical study on O$\\cdots$Br and O$\\cdots$Cl halogen bonds in some small model molecular systems

    Indian Academy of Sciences (India)

    Damanjit Kaur; Rajinder Kaur

    2014-11-01

    Halogen bonding interactions of type X$\\cdots$O=C are important in various fields including biological systems. In this work, theoretical calculations were carried out using B3LYP/6-31++G∗∗, MP2/6-31++G∗∗ and MP2/aug-cc-pVDZ methods on a series of O$\\cdots$X halogen bonds between CH2O andCH3CHO as halogen bond acceptor with X-Y (X = Cl, Br; Y = CF3, CF2 H, CFH2, CN, CCH, CCCN) as halogen bond donors. The strength of interaction energy for O$\\cdots$Br halogen-bonded complexes varies from −2.16 to −5.26 kcal/mol while for O$\\cdots$Cl complexes, it is between −1.65 to −3.67 kcal/mol, which indicate the O$\\cdots$Br bond to be stronger in comparison to O$\\cdots$Cl bond. SAPT analysis suggests that the strength of halogen bonding arises from the electrostatic and induction forces while dispersion is playing a comparatively smaller role. The halogen-bonded interaction energies were found to correlate well with positive electrostatic potential VS,max, halogen bonded distances, and the change in s-character of C-X bond. The halogen-bonded interaction energies were also evaluated for O$\\cdots$I bonded complexes and thus these complexes were found to be stronger than O$\\cdots$Br and O$\\cdots$Cl bonded complexes.

  3. Nutrition chez le brûlé

    Science.gov (United States)

    Perro, G.

    2016-01-01

    Summary La nutrition est un challenge chez le brûlé, paradigme de l’agressé. Les points importants sont les apports entéraux précoces par sonde gastrique voire post pyloriques, la position proclive > 30°, la surveillance du transit et sa régulation par gastro ou entéro-kinétiques, la surveillance du poids, la quantification des apports avec supplémentation parentérale en cas de retard protéino énergétique. Chez l’enfant, l’adhésion à l’alimentation est difficile, de même que chez le senior, où une évaluation nutritionnelle initiale dépiste souvent une dénutrition préexistante. Les compléments alimentaires seront largement prescrits chez les patients de gravité intermédiaire. Les obèses bénéficieront d’un régime hypocalorique et hyperprotidique. Chez l’insuffisant rénal non dialysé il convient de limiter les apports en potassium. En cas brûlure périnéale, on peut proposer soit une constipation de courte durée, soit la mise en place d’un entéro-collecteur, les indications de colostomie étant devenues rares. Les apports entéraux sont difficiles à gérer en cas de décubitus ventral pour SDRA. Chez le brûlé grave de réanimation, l’accent doit plus être mis sur la qualité des nutriments que sur leur quantité. Les anciennes formules d’estimation calorique conduisaient à une surnutrition difficile à administrer et en général mal tolérée; la quantification mesurée par calorimétrie indirecte ou estimée par la formule de Toronto est bien plus adaptée. Plus récemment, l’instauration d’une immunonutrition (supplémentation en vitamines et oligo-éléments, glutamine, arginine, acide Ω 3 et contrôle raisonné de la glycémie) a été proposée pour réduire le stress oxydatif et l’inflammation provoqués par l’accident. PMID:27857647

  4. Pan-Balti bränding - müüt või tegelikkus? / Joel Volkov

    Index Scriptorium Estoniae

    Volkov, Joel, 1972-

    2006-01-01

    Brändil pole kodumaad, on keel ja päritolumaa. Lokaalsed brändid valivad suhtlemiseks kohalikega nende kodukeele, globaalsed brändid harilikult inglise keele. Üks suuremaid ja tugevamaid lokaalsest süsteemist kasvanud Pan-Balti brände on Hansapank. Lisa: Sulev Vedler. Hansast võib saada Swedbank

  5. Inhibition effects of PMA/SbBr3 complex inhibitor on copper and copper-nickel alloy in LiBr solutions

    Institute of Scientific and Technical Information of China (English)

    HU Xian-qi; LIANG Cheng-hao; HUANG Nai-bao

    2005-01-01

    The effects of PMA/SbBr3 inhibitor on copper and copper-nickel alloy in 55%LiBr solution were investigated by chemical immersion and electrochemical measurements. The results indicate that in boiling 55% LiBr solution containing PMA/SbBr3 inhibitor, corrosion rates of copper and copper-nickel alloy are 67.48 μm/a and 38. 14μm/a, respectively. Since both anodic and cathodic electrochemical reactions can be inhibited, PMA/SbBr3 belongs to complex inhibitor. PMA has the effect of inhibiting hydrogen evolution and [PMo12 O40]3- , the anion of PMA,has a strong oxidizing effect. Sb3+ also shows an oxidizing effect. It may exist in LiBr solutions stably with PMA.Because of the synergistic effect of PMA and Sb3+ , a protective film, comprising CuO, Cu2O and Sb, formed on copper and copper-nickel alloy surface may prevent Br- from diffusing to the surface of metals. As a result, the anticorrosion performance of copper and copper-nickel alloy may be improved.

  6. P.R. Subramanian (Chief Editor). <i>Tarkalat Tamil Maraputtotar Akarati (Tamil-Tamil-Ankilam) (Dictionary of Idioms and Phrases in Contemporary Tamil (Tamil-Tamil-English)i>

    OpenAIRE

    Murugan, G.

    2012-01-01

    Review of P.R. Subramanian (Chief Editor). <i>Tarkalat Tamil Maraputtotar Akarati (Tamil-Tamil-Ankilam) (Dictionary of Idioms and Phrases in Contemporary Tamil (Tamil-Tamil-English)i> /><br />Resensie van P.R. Subramanian (Chief Editor). <i>Tarkalat Tamil Maraputtotar Akarati (Tamil-Tamil-Ankilam) (Dictionary of Idioms and Phrases in Contemporary Tamil (Tamil-Tamil-...

  7. Transient resonance Raman spectroscopy and density functional theory investigation of iso-CHBr 2Cl and iso-CCl 3Br photoproducts produced following ultraviolet excitation of CHBr 2Cl and CCl 3Br

    OpenAIRE

    Zheng, X; Lee, CW; Li, YL; Fang, WH; Phillips, DL

    2001-01-01

    Two polyhalomethanes that contain bromine and chlorine atoms (CHBr 2Cl and CCl 2Br) were studied. Transient resonance Raman spectra were obtained for the photoproducts produced after ultraviolet excitation of CHBr 2Cl and CCl 3Br in room temperature solutions and density functional theory calculations for species proposed to be products of the photodissociation reactions in the solution phase. It was found that the iso-CHBrCl-Br and iso-CHClBr-Br species are formed following ultraviolet excit...

  8. CsPb2Br5 Single Crystals: Synthesis and Characterization

    KAUST Repository

    Dursun, Ibrahim

    2017-08-02

    CsPb2Br5 is a ternary halogen-plumbate material with close characteristics to well-reported halide perovskites. Due to its unconventional two-dimensional structure, CsPb2Br5 is being looked at broadly for potential applications in optoelectronics. CsPb2Br5 investigations are currently limited to nanostructures and powder forms of the material, which present unclear and conflicting optical properties. In this study, we present the synthesis and characterization of CsPb2Br5 bulk single crystals, which enabled us to finally clarify the material\\'s optical features. Our CsPb2Br5 crystal has a two-dimensional structure with Pb2Br5- layers spaced by Cs+ cations, and exhibits a ~3.1 eV indirect bandgap with no emission in the visible spectrum.

  9. Radiation-induced pulsed conductivity of CsBr crystals

    CERN Document Server

    Aduev, B P; Shvajko, V N

    2001-01-01

    The radiation-induced conductivity of the CsBr crystals by excitation through the picosecond electron beams (0.2 MeV, 50 ps, 0.1-10 kA/cm sup 2) are studied. The time resolution of the measurement methodology is approx 150 ps. It is shown that the service life of the conductivity zone electrons is limited by the biomolecular recombination with auto localized holes (V sub k -centers). The inertia of the conductivity current pulse growth is determined. The model, according to which the Auger recombination of the valence zone electrons and the upper skeleton zone holes significantly contributes to the conductivity zone electrons generation, is used for explaining this effect

  10. Polyvinylpolypyrrolidone Supported Brønsted Acidic Catalyst for Esterification

    Directory of Open Access Journals (Sweden)

    Song Wang

    2016-01-01

    Full Text Available A polyvinylpolypyrrolidone (PVPP supported Brønsted acidic catalyst ([PVPP-BS]HSO4 was prepared by coupling SO3H-functionalized polyvinylpolypyrrolidone with H2SO4 in this work. After the characterization through FT-IR, FESEM, TG, BET, and elemental analysis, it was found that 1,4-butane sultone (BS and sulfuric acid reacted with PVPP and were immobilized on PVPP surface. The prepared [PVPP-BS]HSO4 catalyst shows high catalytic activity for a series of esterification reactions and could be separated from the reacted mixture easily. Moreover, this catalyst could be recycled and reused for six times without significant loss of catalytic performance.

  11. Numerical modeling of incline plate LiBr absorber

    Science.gov (United States)

    Karami, Shahram; Farhanieh, Bijan

    2011-03-01

    Among major components of LiBr-H2O absorption chillers is the absorber, which has a direct effect on the chillier size and whose characteristics have significant effects on the overall efficiency of absorption machines. In this article, heat and mass transfer process in absorption of refrigerant vapor into a lithium bromide solution of water-cooled incline plate absorber in the Reynolds number range of 5 absorption. An analysis for linear distribution of wall temperature condition carries out to investigate the reliability of the present numerical method through comparing with previous investigation. The effect of plate angle on heat and mass transfer parameters is investigated and the results show that absorption mass flux and heat and mass transfer coefficient increase as the angle of the plate increase. The main parameters of absorber design, namely Nusselt and Sherwood numbers, are correlated as a function of Reynolds Number and the plate angle.

  12. First hydrothermal synthesis of Bi{sub 5}O{sub 7}Br and its photocatalytic properties for molecular oxygen activation and RhB degradation

    Energy Technology Data Exchange (ETDEWEB)

    Su, Yurong; Ding, Chenghua; Dang, Yuanlin [College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061 (China); Wang, Hui [CAS Key Laboratory of Nuclear Radiation and Nuclear Energy Techniques, and Multidisciplinary Initiative Center, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Ye, Liqun, E-mail: yeliquny@163.com [College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061 (China); Jin, Xiaoli [College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061 (China); Xie, Haiquan, E-mail: Xie-hq@163.com [College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061 (China); Liu, Chao [College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061 (China)

    2015-08-15

    Graphical abstract: Bi{sub 5}O{sub 7}Br was firstly synthesized by via hydromel method and showed good photocatalytic properties for molecular oxygen activation and RhB degradation. - Highlights: • Bi{sub 5}O{sub 7}Br, a new Bi{sub x}O{sub y}X{sub z} semiconductor photocatalyst was firstly synthesized by via hydromel method. • As-synthesized Bi{sub 5}O{sub 7}Br can effectively activate molecular oxygen under UV–vis light irradiation. • The appearance of Bi{sub 5}O{sub 7}Br photocatalysis enriched the Bi-O-X photocatalysts. - Abstract: Comparing with BiOX (X = Cl, Br, I), Bi{sub x}O{sub y}X{sub z} as the newest bismuth-based photocatalysts have more appropriate conduction band position. And so, they can be used to active molecular oxygen. In this paper, Bi{sub 5}O{sub 7}Br, a new Bi{sub x}O{sub y}X{sub z} semiconductor photocatalyst was firstly synthesized by via hydromel method. It was characterized by X-ray diffraction (XRD), UV–visible diffused reflectance spectra (DRS), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM) and the corresponding selected-area electron diffraction (SAED) pattern. It can be found that the crystal structure and morphology are same with Bi{sub 5}O{sub 7}I. The size of a single rod is about 2 μm in width and 50 μm in length. As-synthesized Bi{sub 5}O{sub 7}Br can effectively activate molecular oxygen to generate superoxide radical (O{sub 2}{sup •} {sup −}) and hydroxyl radical (• OH) under UV–vis light irradiation. And it also showed high photocatalytic activity than BiOBr for the degradation of dyes. Thus, it can be seen, the appearance of Bi{sub 5}O{sub 7}Br photocatalysis enriched the bismuth-rich strategy of Bi-O-X photocatalysts.

  13. Estudos cromossómicos em <i>Pteridophyta> de Portugal, III

    Directory of Open Access Journals (Sweden)

    Queirós, Margarida

    1997-12-01

    Full Text Available Chromosome numbers of nine taxa of <i>Pteridophyta> from Portugal are reported. Earlier counts of seven of these taxa have been carried out on material from other Portuguese places. <i>Polypodium vulgarei> L. and <i>P. interjectumi> Shivas is now first studied under the caryological point of view.<br>>Se ha estudiado el número cromosómico gamético de nueve táxones de <i>Pteridophyta> portugueses, siete de los cuales coinciden con los datos indicados anteriormente para otras localidades del país. Se dan a conocer por primera vez, en material portugués, los siguientes: <i>Polypodium vulgarei> L. y <i>P. Interjectumi> Shivas.

  14. Infrared spectroscopy of CO sub 2 --D(H)Br: Molecular structure and its reliability

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Y.P.; Sharpe, S.W.; Shin, S.K.; Wittig, C.; Beaudet, R.A. (Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482 (United States))

    1992-10-15

    A high resolution rovibrational absorption spectrum of the weakly bonded CO{sub 2}--DBr complex has been recorded in the 2350 cm{sup {minus}1} region by exciting the CO{sub 2} asymmetric stretch vibration with a tunable diode laser. The CO{sub 2}--DBr band origin associated with this mode is 2348.2710 cm{sup {minus}1}, red-shifted by 0.87 cm{sup {minus}1} from uncomplexed CO{sub 2}. The position of the hydrogen atom is determined from differences in moments-of-inertia between CO{sub 2}--DBr and CO{sub 2}--HBr, i.e., by using the Kraitchman method. From this, we conclude that ground state CO{sub 2}--H(D)Br has an average geometry that is planar and inertially T-shaped, with essentially parallel HBr and CO{sub 2} axes. Average values of intermolecular parameters are: {ital R}{sub cm}=3.58 A, {theta}{sub BrCO}=79.8{degree}, and {theta}{sub HBrC}=93.1{degree}. The validity of using the Kraitchman method, which was designed for use with rigid molecules, with a floppy complex like CO{sub 2}--HBr is discussed. The experimental structure is corroborated qualitatively by results from Moller--Plesset second-order perturbation calculations, corrected for basis set superposition errors. The theoretical equilibrium geometry for the inertially T-shaped complex is planar with structural parameters: {ital R}{sub CBr}=3.62 A, {theta}{sub BrCO}=89{degree}, and {theta}{sub HBrC}=86{degree}. A number of cuts on the four dimensional intermolecular potential surface confirm large zero-point amplitudes, which are known to be characteristic of such systems, and these cuts are used to estimate tunneling splittings. Tunneling is shown to occur by out-of-plane rotation of the H atom, in accord with the experimental observations of Rice {ital et} {ital al}. There is no significant in-plane tunneling.

  15. Infrared spectroscopy of CO2-D(H)Br: Molecular structure and its reliability

    Science.gov (United States)

    Zeng, Y. P.; Sharpe, S. W.; Shin, S. K.; Wittig, C.; Beaudet, R. A.

    1992-10-01

    A high resolution rovibrational absorption spectrum of the weakly bonded CO2-DBr complex has been recorded in the 2350 cm-1 region by exciting the CO2 asymmetric stretch vibration with a tunable diode laser. The CO2-DBr band origin associated with this mode is 2348.2710 cm-1, red-shifted by 0.87 cm-1 from uncomplexed CO2. The position of the hydrogen atom is determined from differences in moments-of-inertia between CO2-DBr and CO2-HBr, i.e., by using the Kraitchman method. From this, we conclude that ground state CO2-H(D)Br has an average geometry that is planar and inertially T-shaped, with essentially parallel HBr and CO2 axes. Average values of intermolecular parameters are: Rcm=3.58 Å, θBrCO=79.8°, and θHBrC=93.1°. The validity of using the Kraitchman method, which was designed for use with rigid molecules, with a floppy complex like CO2-HBr is discussed. The experimental structure is corroborated qualitatively by results from Møller-Plesset second-order perturbation calculations, corrected for basis set superposition errors. The theoretical equilibrium geometry for the inertially T-shaped complex is planar with structural parameters: RCBr=3.62 Å, θBrCO=89°, and θHBrC=86°. A number of cuts on the four dimensional intermolecular potential surface confirm large zero-point amplitudes, which are known to be characteristic of such systems, and these cuts are used to estimate tunneling splittings. Tunneling is shown to occur by out-of-plane rotation of the H atom, in accord with the experimental observations of Rice et al. There is no significant in-plane tunneling. A quasilinear hingelike isomer (OCO-HBr) with ROH=2.35 Å at equilibrium is calculated to be as stable as the T-shaped complex; however, this species has yet to be observed experimentally. Photoinitiated reactions in CO2-HX complexes are discussed.

  16. Research on immune effect of two gene vaccines containing brZPC' and brLDHC4' when in combined inoculation

    Institute of Scientific and Technical Information of China (English)

    Xu Li; Peng Jing-pian

    2012-01-01

    ZPC and LDHC4 play a key role in the process of recognition between sperm and egg or sperm movement,respectively.In this study,partial cDNA sequences of ZPC and LDH-C4 of Microtus branditi (brZPC' and brLDHC4',respectively) were cloned by RT PCR,and directly inserted into pCR3.1 vector to construct two gene vaccines (pCR3.1-brZPC' and pCR3.1-brLDHC4').pCR3.1-brZPC' and pCR3.1-brLDHC4' could express corresponding proteins in transiently transfected CHO cells.The adult female BALB/c mice were inoculated with the recombinant vaccine alone on in combination.The immunized mouse can produce specific antibody that recognizes the corresponding recombinant protein expressed by BL21 in vitro.Moreover,antibodies produced by combinedly immunized mouse were specific and direct,with no inhibitory effect between two vaccines observed when in combined inoculation.The test of cytokines indicated that the expression of IFNγ in pCR3.1-brZPC'-and combinedly inoculated mouse increased obviously and the expression of IL2 in pCR3.1-brLDHC4 '-and combinedly inoculated mouse increased obviously,while the expression of IL4 in pCR3.1-brZPC',pCR3.1-brLDHC4'and combinedly inoculated group increased obviously.It was suggested that the combined inoculation with pCR3.1-brZPC' and pCR3.1-brLDHC4 ' could induce both humoral immune response and CTL response.In some sense,the combined inoculation may achieve a better contraceptive effect.The results also showed that,when used alone or in combination,these two recombinant vaccines did not do much harm to the follicular development of immunized mouse.So the combined inoculation with these two recombinant vaccines could be a better way to immunocontraception.This study may provide a theoretical basis for the following tests on antifertility in vivo.

  17. Retrieval and Observations of Atmospheric BrO from SCIAMACHY nadir Measurements

    OpenAIRE

    Afe, Oluyemi Temitayo

    2005-01-01

    Measurements from the space-borne instrument SCIAMACHY launched in March 2002 onboard the ENVISAT platform, have been analysed for BrO absorption using the Differential Optical Absorption Spectroscopy (DOAS) method. BrO is an important atmospheric trace gas mainly responsible for the depletion of ozone in the polar boundary layer, the free troposphere and the stratosphere. Since 1995, global observations of BrO have been successfully demonstrated by the GOME instrument in several publications...

  18. File list: ALL.Brs.10.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Brs.10.AllAg.SK-BR-3 hg19 All antigens Breast SK-BR-3 SRX155755,SRX750670,SRX75...0675,SRX750660,SRX750665,SRX155756,SRX128102,SRX155754,SRX469109,SRX469108,SRX469107 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.Brs.10.AllAg.SK-BR-3.bed ...

  19. File list: ALL.Brs.50.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Brs.50.AllAg.SK-BR-3 hg19 All antigens Breast SK-BR-3 SRX750670,SRX750665,SRX12...8102,SRX750660,SRX750675,SRX469109,SRX469107,SRX469108,SRX155755,SRX155756,SRX155754 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.Brs.50.AllAg.SK-BR-3.bed ...

  20. File list: ALL.Brs.20.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Brs.20.AllAg.SK-BR-3 hg19 All antigens Breast SK-BR-3 SRX750670,SRX750665,SRX75...0675,SRX155755,SRX155756,SRX128102,SRX750660,SRX155754,SRX469109,SRX469107,SRX469108 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.Brs.20.AllAg.SK-BR-3.bed ...

  1. File list: ALL.Brs.05.AllAg.SK-BR-3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Brs.05.AllAg.SK-BR-3 hg19 All antigens Breast SK-BR-3 SRX155754,SRX155755,SRX75...0670,SRX750660,SRX750675,SRX750665,SRX155756,SRX128102,SRX469109,SRX469108,SRX469107 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.Brs.05.AllAg.SK-BR-3.bed ...

  2. [Oxidation of mercury by CuBr2 decomposition under controlled-release membrane catalysis condition].

    Science.gov (United States)

    Hu, Lin-Gang; Qu, Zan; Yan, Nai-Qiang; Guo, Yong-Fu; Xie, Jiang-Kun; Jia, Jin-Ping

    2014-02-01

    CuBr2 in the multi-porous ceramic membrane can release Br2 at high temperature, which was employed as the oxidant for Hg0 oxidation. Hg0 oxidation efficiency was studied by a membrane catalysis device. Meanwhile, a reaction and in situ monitoring device was designed to avoid the impact of Br2 on the downstream pipe. The result showed that the MnO(x)/alpha-Al2O3 catalysis membrane had a considerable "controlled-release" effect on Br2 produced by CuBr2 decomposition. The adsorption and reaction of Hg0 and Br2 on the surface of catalysis membrane obeyed the Langmuir-Hinshelwood mechanism. The removal efficiency of Hg0 increased with the rising of Br2 concentration. However, when Br2 reached a certain concentration, the removal efficiency was limited by adsorption rate and reaction rate of Hg0 and Br2 on the catalysis membrane. From 473 K to 573 K, the variation of Hg0 oxidation efficiency was relatively stable. SO2 in flue gas inhibited the oxidation of Hg0 while NO displayed no obvious effect.

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

    OpenAIRE

    Theys, N.; Van Roozendael, M.; Hendrick, F.; Yang, X.; Smedt, I. De; Richter, A.; Begoin, M.; Q. Errera; Johnston, P. V.; Kreher, K.; De Mazière, M.

    2011-01-01

    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 ...

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

    OpenAIRE

    Theys, N.; Van Roozendael, M.; Hendrick, F.; Yang, X.; Smedt, I. De; Richter, A.; Begoin, M.; Q. Errera; Johnston, P. V.; Kreher, K.; De Mazière, M.

    2010-01-01

    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 ...

  5. Stratospheric BrO abundance measured by a balloon-borne submillimeterwave radiometer

    Directory of Open Access Journals (Sweden)

    R. A. Stachnik

    2012-11-01

    Full Text Available Measurements of mixing ratio profiles of stratospheric bromine monoxide (BrO were made using observations of BrO otational line emission at 650.179 GHz by a balloon-borne SIS (superconductor-insulator-superconductor submillimeterwave heterodyne receiver. The balloon was launched from Ft. Sumner, New Mexico (34°N on 22 September 2011. Peak mid-day BrO abundance varied from 16 ± 2 ppt at 34 km to 6 ± 4 ppt at 16 km. Corresponding estimates of total inorganic bromine (Bry, derived from BrO vmr (volume mixing ratio using a photochemical box model, were 21 ± 3 ppt and 11 ± 5 ppt, respectively. Inferred Bry abundance exceeds that attributable solely to decomposition of long-lived methyl bromide and other halons, and is consistent with a contribution from bromine-containing very short lived substances, BryVSLS, of 4 ppt to 8 ppt. These results for BrO and Bry were compared with, and found to be in good agreement with, those of other recent balloon-borne and satellite instruments.

  6. Phase diagram and enhanced electrical transport in KBr-NaBr mixed crystals

    Energy Technology Data Exchange (ETDEWEB)

    Manoravi, P. (Dept. of Physics, Indian Inst. of Tech., Kanpur (India)); Shahi, K. (Dept. of Physics, Indian Inst. of Tech., Kanpur (India) Material Science Program, Indian Inst. of Tech., Kanpur (India))

    1991-03-01

    Phase diagram and ionic conductivity of KBr-NaBr mixed crystals system have been studied over the entire composition and stable temperature range. A maximum conductivity enhancement by a factor of 25 with respect to pure KBr, and 8 with respect to pure NaBr, is obtained for the K{sub 0.5}Na{sub 0.5}Br solid solution at 500deg C. The conductivity values are found to follow the melting (solidus) temperature in a correlated manner. The minimum in the solidus curve of the phase diagram is observed between 43 and 72 mole% NaBr at 615deg C. (orig.).

  7. Non-Adiabatic Dynamics of ICN-(Ar)n and BrCN-(Ar)n

    Science.gov (United States)

    Opoku-Agyeman, Bernice; McCoy, Anne B.

    2016-06-01

    We investigate the dynamics of the photodissociation of ICN-(Ar)n and BrCN-(Ar)n following electronic excitation to states that dissociate into X- + CN and X* + CN- (X = I or Br) using classical dynamics approaches. Observations made from previous experiments and calculations of these anions demonstrated that non-adiabatic effects are important in the photodissociation process and are reflected in the branching ratios of the photoproducts. The addition of an argon atom is expected to shift the relative energies of these excited states, thereby altering the product branching. Interestingly, experimental studies show that electronically exciting ICN- solvated with even a single argon atom leads to a small fraction of the products recombine to form ICN-.a In this study, the dynamics are carried out using classical mechanics, treating the non-adiabatic effect with a surface hopping algorithm. We assess the accuracy of this approach by first calculating the branching ratios for the bare anions and comparing the results to those from quantum dynamics calculations.a,b Once the results from both the quantum and classical dynamics are shown to be consistent, the classical dynamics simulations are extended to the argon solvated anions. S. Case, E. M. Miller, J. P. Martin, Y. J. Lu, L. Sheps, A. B. McCoy, and W. C. Lineberger, Angew. Chem., Int. Ed. 51, 2651 (2012). B. Opoku-Agyeman, A. S. Case, J. H. Lehman, W. Carl Lineberger and A. B. McCoy, J. Chem Phys. 141, 084305 (2014). J. C. Tully, J. Chem Phys. 93, 1061 (1990).

  8. Styrene oligomerization as a molecular probe reaction for Brønsted acidity at the nanoscale.

    Science.gov (United States)

    Aramburo, Luis R; Wirick, Sue; Miedema, Piter S; Buurmans, Inge L C; de Groot, Frank M F; Weckhuysen, Bert M

    2012-05-21

    The Brønsted acid-catalyzed oligomerization of 4-fluorostyrene has been studied on a series of H-ZSM-5 zeolite powders, steamed under different conditions, with a combination of UV-Vis micro-spectroscopy and Scanning Transmission X-ray Microscopy (STXM). UV-Vis micro-spectroscopy and STXM have been used to monitor the relative formation of cyclic and linear dimeric carbocations as a function of the steaming post-treatment (i.e., parent vs. steaming at 600, 700 and 800 °C). It was found that the UV-Vis band intensity ratios of linear to cyclic dimeric species increase from 0.79 (parent H-ZSM-5) over 1.41 (H-ZSM-5 steamed at 600 °C) and 1.88 (H-ZSM-5 steamed at 700 °C) to 2.33 (H-ZSM-5 steamed at 800 °C). STXM confirms this trend in reaction product selectivity, as the relative intensities of the transitions attributed to the presence of the cyclic dimer in the carbon K-edge spectra decrease with increasing severity of the steaming post-treatment. Furthermore, STXM reveals spatial heterogeneities in reaction product formation within the H-ZSM-5 zeolite powders at the nanoscale. More specifically, a shrinking carbon core-shell distribution was detected within the zeolite aggregates, in which the relative amount of cyclic dimeric species is higher in the core relative to the shell of the zeolite aggregate and the relative amount of cyclic dimeric species in the zeolite core gradually decreases with increasing severity of the steaming post-treatment. These differences are rationalized in terms of spatial differences in Brønsted acidity within H-ZSM-5 zeolite powders as well as by changes in the formation process of linear and dimeric carbocations within H-ZSM-5 micro- and mesopores.

  9. Spatial distribution of erosion and deposition during a glacier surge: Brúarjökull, Iceland

    Science.gov (United States)

    Korsgaard, Niels J.; Schomacker, Anders; Benediktsson, Ívar Örn; Larsen, Nicolaj K.; Ingólfsson, Ólafur; Kjær, Kurt H.

    2015-12-01

    Time-series of digital elevation models (DEMs) of the forefield of the Brúarjökull surge-type glacier in Iceland were used to quantify the volume of material that was mobilized by the 1963-1964 surge. The DEMs were produced by stereophotogrammetry on aerial photographs from before the surge (1961) and after (1988 and 2003). The analysis was performed on two DEMs of Difference (DoDs), i.e., a 1961-2003 DoD documenting the impact of the surge and a 1988-2003 DoD documenting the post-surge modification of the juvenile surging glacier landsystem. Combined with a digital geomorphological map, the DoDs allow us to quantify the impact of the surge on a landsystem scale down to individual landforms. A total of 34.2 ± 11.3 × 106 m3 of material was mobilized in the 30.7-km2 study area as a result of the most recent surge event. Of these, 17.4 ± 6.6 × 106 m3 of the material were eroded and 16.8 ± 4.7 × 106 m3 were deposited. More than half of the deposited volume was ice-cored landforms. This study demonstrates that although the total mobilized mass volume is high, the net volume gain of ice and sediment deposited as landforms in the forefield caused by the surge is low. Furthermore, deposition of new dead-ice from the 1963-1964 surge constitutes as much as 64% of the volume gain in the forefield. The 1988-2003 DoD is used to quantify the melt-out of this dead-ice and other paraglacial modification of the recently deglaciated forefield of Brúarjökull.

  10. DMS and MSA measurements in the Antarctic Boundary Layer: impact of BrO on MSA production

    Directory of Open Access Journals (Sweden)

    K. A. Read

    2008-06-01

    Full Text Available In situ measurements of dimethyl sulphide (DMS and methane sulphonic acid (MSA were made at Halley Station, Antarctica (75°35' S, 26°19' W during February 2004–February 2005 as part of the CHABLIS (Chemistry of the Antarctic Boundary Layer and the Interface with Snow project. DMS was present in the atmosphere at Halley all year (average 38.1±43 pptV with a maximum monthly average value of 113.6±52 pptV in February 2004 coinciding temporally with a minimum in sea extent. Whilst seasonal variability and interannual variability can be attributed to a number of factors, short term variability appeared strongly dependent on air mass origin and trajectory pressure height. The MSA and derived non-sea salt sulphate (nss-SO42− measurements showed no correlation with those of DMS (regression <i>R>2=0.039, and <i>R>2=0.001 respectively in-line with the complexity of DMS fluxes, alternative oxidation routes, transport of air masses and variable spatial coverage of both sea-ice and phytoplankton. MSA was generally low throughout the year, with an annual average of 42 ng m−3 (9.8±13.2 pptV, however MSA: nss-SO42− ratios were high implying a dominance of the addition oxidation route for DMS. Including BrO measurements into MSA production calculations demonstrated the significance of BrO on DMS oxidation within this region of the atmosphere in austral summer. Assuming an 80% yield of DMSO from the reaction of DMS+BrO, an atmospheric concentration of BrO equal to 3 pptV increased the calculated MSA production from DMS by a factor of 9 above that obtained when considering only reaction with the hydroxyl radical. These findings have significant atmospheric implications, but may also impact on the interpretation of ice cores which previously relied on the understanding of MSA and nss-SO42− chemistry to provide information on

  11. Aproximación a las <i>Epístolas> de Giovanni Manardo

    Directory of Open Access Journals (Sweden)

    Valderas, José María

    1997-12-01

    Full Text Available Up until Manardo's entry into science, most botanical research had been based on Plinian expurgated texts. This began lo change in the 1520s. Manardo's <i>Epistolae Medicinalesi> were a pathbreaking investigations of plants. Dioscorides is now the source.<br>>Las <i>Epistolae> medicinales de Manardo suponen el final de una botánica fundada en la depuración de los textos de Plinio, perdurante hasta finales del siglo XV, y el comienzo de una línea basada en el conocimiento de Dioscórides, curso que seguirán los grandes naturalistas del siglo XVI.

  12. Isolating mechanisms among five sympatric species of Aneilema,/i> R. Br. (Commelinaceae in Kenya

    Directory of Open Access Journals (Sweden)

    R. B. Faden

    1983-12-01

    Full Text Available The reproductive biology and ecology of five non-hybridizing, sympatric species of Aneilema in Kenya is investigated. The high number of species at the study site is believed to be due to the ecological diversity at this locality. Differences in ecology and seasonal flowering periods appear to be inadequate to reproductively isolate these species. However, differences in daily flowering times, pollinators, floral morphology and opening behaviour, and in chromosome number, alone or in combination (perhaps also coacting with other factors not fully evaluated, are effective isolating mechanisms.

  13. Br NQR relaxation and successive phase transitions of CH{sub 3}NH{sub 3}HgBr{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Niki, H., E-mail: niki@sci.u-ryukyu.ac.jp; Higa, K.; Okada, Y.; Oshiro, M.; Yogi, M. [University of the Ryukyus, Department of Physics, Faculty of Science (Japan); Terao, H. [Tokushima University, Department of Chemistry, Faculty of Integrated Arts and Sciences (Japan)

    2010-06-15

    The measurement of {sup 81}Br NQR in CH{sub 3}NH{sub 3}HgBr{sub 3} has been carried out in the temperature range between 80 and 300 K using a pulse NQR method. The temperature dependence of {sup 81}Br NQR frequencies in CH{sub 3}NH{sub 3}HgBr{sub 3} has revealed that it undergoes three characteristic successive phase transitions at T = 123, 184 and 239 K. The phase transition temperature at T = 239 K is the second-order type, whereas those at T = 184 and 123 K are the first-order nature of the phase transitions. Each phase transition seems to be closely related to the motions of methyl ammonium cation as a partial or whole. The enhancement of 1/T{sub 1} at T = 239 K indicates the onset of the molecular motion of the cation as a whole with increasing temperatures.

  14. Ultraviolet Spectroscopy of the Massive LMC Multiple Systems Sk-6718 (Br+.1667em5 and HD+.1667em36402 (Br+.1667em31

    Directory of Open Access Journals (Sweden)

    G. Koenigsberger

    2003-01-01

    Full Text Available Reportamos los resultados de observaciones en el UV de dos sistemas binarios cercanos, ubicados en la Nube Mayor de Magallanes, Br 5 y Br 31. Detectamos variabilidad espectral en Br 31 producida por eclipses atmosféricos, así como variaciones en la velocidad radial de algunas de sus líneas, con el periodo de 3.033 días. El espectro UV de este sistema es consistente con la presencia de 3 estrellas calientes en el sistema. En contraste, no podemos confirmar la presencia de más de 2 estrellas calientes en el sistema Br 5, y la debilidad de Si IV 1400 contradice la presencia de una supergigante O-tardía o B-temprana. Detectamos variaciones de velocidad radial consistentes con el movimiento orbital de la componente O3 If*.

  15. Taxonomic review of the genus <i>Chamaemelum> Miller (<i>Asteraceae> in the Iberian peninsula and the Balearic lslands

    Directory of Open Access Journals (Sweden)

    Benedí i González, Carles

    1988-01-01

    Full Text Available A taxonomic review of the genus <i>Chamaemelum> Miller (<i>Asteraceae> in the Iberian peninsula and the Balearic Islands is carried out. Two changes in nomenclature are proposed: <i>Chamaemelum nobilei> ( L. All. forma <i>discoideum> (Willk. comb. & stat. nov. and <i>C. fuscatumi> (Brot. Vasc. forma <i>minor> (Hoffmanns. & Link comb. & stat. nov. For each taxon the correct name as well as the corresponding synonyms are given. A dichotomic key of the recognized taxa and a list of the herharium sheets studied are provided.<br>>Se realiza una revisión taxonómica del género <i>Chamaemelum> Miller (<i>Asteraceae> en la Península Ibérica e Islas Baleares. Se proponen dos cambios nomenclaturles: <i>Chamaemelum nobilei> (L. All. forma <i>discoideum> (Willk. comb. & stat. nov. y <i>C. fuscatumi> (Brot. Vasc. forma <i>minor> (Hoffmanns. & Link comb. & stat. nov. Para cada taxon se da el nombre correcto, así como las correspondientes sinonimias. Se adjunta una clave dicotómica de los táxones reconocidos y una relación de los testimonios de herbario estudiados.

  16. Barack Obama, Ano I

    OpenAIRE

    ANTÔNIO LASSANCE

    2010-01-01

    Que tipo de presidente é Barack Obama?<br />Este artigo sugere: nem Lincoln, como nos sonhos do<br />próprio Obama, nem Carter, como os Republicanos<br />pintam. Lyndon Johson é o arquétipo mais próximo,<br />devido a vários aspectos. O mais importante são as<br />duas agendas similares: uma, em política externa,<br />herdada, é a agenda da guerra; a outra, nas políticas<br />públicas domésticas, se refere à expansão dos direitos<br />sociais. T...

  17. Systematic hardness measurements on CsClBr(1–x) and NH4ClBr(1–x) mixed crystals

    Indian Academy of Sciences (India)

    K G Subhadra; E Balaiah; D B Sirdeshmukh

    2002-02-01

    Vickers hardness measurements have been made on polycrystalline blanks of CsClBr(1–x) and single crystals of NH4ClBr(1–x). The composition dependence of hardness is highly nonlinear in both systems and follows an empirical model that includes a lattice contribution and a disorder contribution. The Gilman–Chin parameter (/44) has been calculated and its significance discussed.

  18. Nutrient/serum starvation derived TRIP-Br3 down-regulation accelerates apoptosis by destabilizing XIAP

    Science.gov (United States)

    Lee, Soonduck; Jeong, Dongjun; Yang, Young; Kim, Keun-Il; Lim, Jong-Seok; Cheon, Chung-Il; Kim, Changjin; Kang, Young-Sook; Lee, Myeong-Sok

    2015-01-01

    TRIP-Br3 and TRIP-Br1 have shown to have important biological functions. However, the function of TRIP-Br3 in tumorigenesis is not well characterized compared to oncogenic TRIP-Br1. Here, we investigated the function of TRIP-Br3 in tumorigenesis by comparing with that of TRIP-Br1. Under nutrient/serum starvation, TRIP-Br3 expression was down-regulated slightly in cancer cells and significantly in normal cells. Unexpectedly, TRIP-Br1 expression was greatly up-regulated in cancer cells but not in normal cells. Moreover, TRIP-Br3 activated autophagy while TRIP-Br1 inactivated it under serum starvation. In spite of different expression and roles of TRIP-Br3 and TRIP-Br1, both of them alleviate cell death by directly binding to and stabilizing XIAP, a potent apoptosis inhibitor, through blocking its ubiquitination. Taken together, we propose that TRIP-Br3 primarily activates the autophagy and suppresses apoptosis in nutrient sufficient condition. However, the prolonged extreme stressful condition of nutrient starvation causes a dramatic decrease of TRIP-Br3, which in turn induces apoptosis by destabilizing XIAP. Up-regulated TRIP-Br1 in cancer cells compensates this effect and delays apoptosis. This can be explained by the competitive alternative binding of TRIP-Br3 and TRIP-Br1 to the BIR2 domain of XIAP. In an extended study, our immunohistochemical analysis revealed a markedly lower level of TRIP-Br3 protein in human carcinoma tissues compared to normal epithelial tissues, implying the role of TRIP-Br3 as a tumor suppressor rather than onco-protein. PMID:25691055

  19. 可换BR0代数的刻画和性质%Characterizations and properties of commutative BR0-algebras

    Institute of Scientific and Technical Information of China (English)

    凌雪岷; 徐罗山

    2012-01-01

    为了得到基础R0代数(简称BR0代数)的更多表示和性质,利用蕴涵算子给出了可换BR0代数的两种形式更为简单的刻画;证明了可换BR0代数与有界可换BCK代数之间的等价性;证明了满足Heyting性质(HP条件)的可换BR0代数与正则Heyting型FI代数(即HFI代数)等价.%In order to obtain more properties and representations of basic Ro-algebras (in short, Bro-algebras), in this paper, two new characterizations of commutative BR0-algebras are given in terms of implication operators. It is proved that commutative Bro-algebras and bounded commutative BCK-algebras are equivalent. It is also proved that commutative BR0 -algebras satisfying the Heyting property (or, HP condition) are equivalent to regular Heyting type Fl-algebras (in short, HFI-algebras).

  20. Laser cooling of CaBr molecules and production of ultracold Br atoms: A theoretical study including spin-orbit coupling.

    Science.gov (United States)

    Fu, Mingkai; Ma, Haitao; Cao, Jianwei; Bian, Wensheng

    2017-04-07

    Owing to the exciting potential applications of ultracold atoms and molecules in many fields, developing new cooling schemes has attracted great interests in recent years. Here, we investigate laser cooling of CaBr molecules and design a photonic scheme for the production of ultracold Br atoms using the highly accurate ab initio and dynamical methods. We find that the AΠ1/22(ν(')=0)→X(2)Σ1/2(+)(ν=0) transition for CaBr features a large vibrational branching ratio, a significant photon-scattering rate, and no intermediate electronic-state interference, indicating that the ultracold CaBr could be produced through a three-laser cooling scheme. Moreover, an efficient four-pulse excitation scheme from the ground rovibrational level of the cooled CaBr molecules is proposed to yield ultracold Br atoms, in which a few spin-orbit excited states are utilized as the intermediate states. The importance of the spin-orbit coupling is underscored in this work.

  1. Ionic Conductivities of Molten CuI and AgI-CuI Mixtures

    Science.gov (United States)

    Tahara, Shuta; Shimakura, Hironori; Ohno, Satoru; Fukami, Takanori

    2017-08-01

    Ionic conductivities σ for molten CuI and AgI-CuI mixtures were measured in the temperature ranges of approximately 580-800 and 500-850 °C, respectively. The value of σ for molten CuI in the range is smaller than that for molten CuBr and CuCl. σ for molten AgI-CuI mixtures decreases with increasing CuI-concentration. The activation energies Ea for molten AgI-CuI system were determined from the analysis of temperature dependence of σ by using the by Arrhenius type equation. Ea for molten AgI-CuI gradually increase with increasing CuIconcentration.

  2. Data of evolutionary structure change: 1MRUA-2BR1A [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1MRUA-2BR1A 1MRU 2BR1 A A TPSHLSDRYELGEILGFGGMSEVHLARDLRLHRDVAVKV... HHHHHHHHHH HHHH - HHHGGG- HHHH 0 1MRU... A 1MRUA EPPFT--GDSPV ARG CA 259 ARG CA 219 GLU CA 163 1MRU... A 1MRUA IVAVYDTG

  3. Measurement and simulation of proton induced activation of LaBr3 : Ce

    NARCIS (Netherlands)

    Buis, E. J.; Beijers, H.; Brandenburg, S.; Bos, A. J. J.; Dathy, C.; Dorenbos, P.; Drozdowski, W.; Kraft, S.; Maddox, E.; Ostendorf, R. W.; Owens, A.; Quarati, F.

    2007-01-01

    To assess the suitability of LaBr3:Ce scintillators for space mission applications, proton induced activation of LaBr3 has been investigated. The crystals were irradiated using proton beams at several different energies to mimic the spectrum of a solar flare. We have measured the activation both int

  4. Limit on Br(b --> sg) in two Higgs doublet models

    CERN Document Server

    Geng, C Q; Hou Wei Shu; Chao-Qiang Geng; Paul Turcotte; Wei-Shu Hou

    1994-01-01

    Using the recent CLEO measurement of Br(b\\to s \\gamma), we find that the branching ratio of b\\to s g cannot be larger than 10\\% in two Higgs doublet models. The small experimental value of Br(b\\to e\\bar{\

  5. Resonance Raman Spectra of the Transient Cl2 and Br2 Radical Anions

    DEFF Research Database (Denmark)

    Wilbrandt, Robert Walter; Jensen, Niels-Henrik; Sillesen, Alfred Hegaard

    1984-01-01

    The resonance Raman spectra of the short-lived radical anions ClImage 2− and BrImage − in aqueous solution are reported. The observed wavenumbers of 279 cm−1 for ClImage − and 177 cm−1 for BrImage − are about 10% higher than those published for the corresponding species isolated in solid argon...

  6. (abstract) BrO and HOBr: New Results for Familiar Molecules

    Science.gov (United States)

    Cohen, E. A.; Muller, H. S. P.; Tan, T. L.; McRae, G. A.; Johns, J. W. C.

    1996-01-01

    As part of a program at our laboratory to extend the spectroscopic database of the halogen oxides and oxo-acids which participate in atmospheric ozone chemistry, we have continued the investigations on BrO and HOBr. The rotational spectra for certain states of BrO have been observed for the first time. Observations of other states have been extended.

  7. Electrochemical Characterization of Benzoyl Formic Acid at Glassy Carbon Electrode in Ionic Liquid: [emim]Br

    Institute of Scientific and Technical Information of China (English)

    赵鹏; 孙茜; 王欢; 陆嘉星; 何鸣元

    2005-01-01

    The direct electrochemical reduction of benzoyl formic acid was investigated in ionic liquid, 1-ethyl-3-methyl-imidazolium bromide ([emim]Br), using cyclic voltammetry and chronocoulometry. The diffusion coefficient (D) and the transfer coefficient (α) of benzoyl formic acid in [emim]Br were obtained.

  8. Inhibition of hydrogen oxidation by HBr and Br2

    DEFF Research Database (Denmark)

    Dixon-Lewis, Graham; Marshall, Paul; Ruscic, Branko;

    2012-01-01

    The high-temperature bromine chemistry was updated and the inhibition mechanisms involving HBr and Br2 were re-examined. The thermochemistry of the bromine species was obtained using the Active Thermochemical Tables (ATcT) approach, resulting in improved data for, among others, Br, HBr, HOBr and ...

  9. Thermodynamic and structural properties of high temperature solid and liquid EuBr2

    DEFF Research Database (Denmark)

    Rycerz, L.; Gadzuric, S.; Ingier-Stocka, E.

    2005-01-01

    Heat capacity of solid and liq. EuBr2 was measured by differential scanning calorimetry in the temp. range 300-1100 K. The temp. and enthalpy of fusion were also detd. exptl. By combination of these results with the literature data on the entropy at 298.15 K, S(o,m) (EuBr2, s, 298.15 K...

  10. <i>Delphinium> L. Subgen. <i>Delphinium>: origin and evolutionary trends

    Directory of Open Access Journals (Sweden)

    Blanché, Cèsar

    1990-12-01

    Full Text Available The advanced features of <i>Delphinium> lo subgen. <i>Delphinium>(annual taxa are compared with those of subgen. <i>Delphinastrum> (DC. Wang and subgen. <i>Oligophyllon> Dimitrova (perennial taxa. F1ower morphology shows a functional interchange between lateral petals and upper petals. and inflorescence structure favours geitonogamy-autogamy rates. Karyotype evolution is based on a decrease in the total length of chromosomes and on an increase in the degree of asymmetry: the chromosome number remains constant (2n = 16 in the subgen. <i>Delphinium>.The dispersal efficiency of the annual species is higher than that of perennials due to seed set increase and improved floatability. both in water and in air. Other advanced adaptive features are the acquisition or new chemical weapons and the emergence of a new embryonogenic type. The ecological niches or subgen. <i>Delphinium> correspond to open and disturbed habitats in contrast to the stable and relatively closed ones or subgenera <i>Delphinastum> and <i>Oligophyllon>. A final hypothesis is made concerning the evolutionary trends observed in annuals vs. perennials in connexion with biogeographical considerations, and a final taxonomic summary is given.<br>>[ca] Les característiques avançades de <i>Delphinium> L. subgèn. <i>Delphinium> (tàxons anuals són comparades amb les del subgèn. <i>Delphinastrum> (DC. Wang i del subgèn. <i>Oligophyllon> Dimitrova (tàxons perennes. La morfologia norai mostra un intercanvi de funcions entre els pètals laterals i els pètals superiors i l'estructura de la inflorescència de molts tàxons anuals afavoreix un augment de les taxes de geitonogàmia-autogàmia. L'evolució dels cariotips és basada en una disminució de la longitud total dels cromosomes i en un increment del grau d'asimetria; el nombre cromosòmic roman constant per a totes les espècies anuals (2n = 16. l'eficàcia de la dispersió de les esp

  11. Nematocid effects of watercress (Nasturtium officinale R. Br.

    Directory of Open Access Journals (Sweden)

    Helena Zahradníková

    2013-01-01

    Full Text Available The watercress (Nasturtium officinale R. Br. is often grown as a forced leaf vegetable rich in vitamins and minerals. Its specific taste and curative effects result from the presence of mustard glycosides (glucosinolates that may also show nematocidic effects. The aim of this study was to evaluate the effect of watercress eluate and juice on tomato plants inoculated with the northern root-knot nematode (NRKN Meloidogyne hapla. It was found out that after the treatment of plants with solutions derived from watercress the yield of fruit was highly significantly increased. The highest yield increase (by 96 % to 165 % was observed in the variant with the highest concentration of watercress extracts (macerate + 200 ml of juice. Although at lower concentrations of watercress solution the increase in yields was also reduced (by 57–118 %, the difference was still statistically highly significant. The effect of this treatment on the content of vitamin C was similar and the increase was also highly significant and ranged from 24 to 67 %. When evaluating the occurrence of nematodes on roots of tomato plants, the presence of pathogens was equal to zero percent in all treated variants. The treatment with this phyto-solution corroborated not only a nematocidic effect of watercress but also its positive influence on the yield and level of vitamin C in dependence on increasing concentrations of the effective agent. It can be therefore concluded that the watercress solution showed a promoting effect on tomato plants.

  12. Photo-dissociation of dimethylamine by KrBr* excilamp.

    Science.gov (United States)

    Han, Qiuyi; Ye, Zhaolian; Zhao, Jie; Lister, Graeme; Zhang, Shanduan

    2013-10-01

    A study of dimethylamine photo-dissociation in the gas phase has been conducted using UV radiation delivered from a KrBr(*) excilamp, driven by a sinusoidal electronic control gear with maximum emission at wavelength of 207 nm. The electrical input power and radiant power of the lamp were measured to determine their effects on the degradation. The influence of flow velocity and initial concentration of dimethylamine were also examined. In order to evaluate the photo-dissociation process comprehensively, several parameters were investigated, including removal efficiency, energy yield, carbon balance and CO₂ selectivity. It is shown that the removal efficiency increases with enhanced input power and decreased gas flow rate. A high removal efficiency of 68% is achieved for lamp power 102W and flow velocity 15 m(3) h(-1). The optimum dimethylamine initial concentration is around 3520 mg m(-3), for which the energy yield reaches up to 442 gk Wh(-1) when the input power is 65W. In addition, two chain compounds (1,3-bis-dimethylamino-2-propanol; 3-penten-2-one, 4-amino) and three ring organic matters (1-azetidinecarboxaldehyde, 2,2,4,4-tetramethyl; N-m-tolyl-succinamic acid; p-acetoacetanisidide), were identified by GC-MS as secondary products, in order to demonstrate the pathways of the dimethylamine degradation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. An Exergy Analysis of LiBr-Water Absorption Refrigerators

    Science.gov (United States)

    Asano, Hitoshi; Fujii, Terushige; Wang, Xiao; Origane, Takafumi; Katayama, Masatoshi; Inoue, Umeo

    Absorption refrigerators are very efficient as a heat recovery unit in a co-generation system.In order to design an absorption refrigerator for an arbitrary heat source properly, it is important to consider not only quantity but also quality of heat flow. The evaluation of exergy loss in each component is also effective for the improvement of system. This paper deals with the exergy analysis on a LiBr-water absorption refrigerator consisted of a single-and a double-effect cycle driven by the exhaust gas of the micro gas turbine with the output power of about 30 kW. Moreover, exergy loss in absorption process was eva1uated. As a result, it was shown that 80% of the exergy loss in an absorber was caused in absorption process, and the exergy loss decreased with decreasing the change in solution concentration in absorber. In these calculated results,the maximum cooling load of 77.8 kW was obtained from the exhaust gas with the temperature of 2900°C by utilizing both a single-and a double-effect cycles in combination. The energy and exergy efficiency of the system was 88.0% and 25.6%, respectively.

  14. Highly Emissive Divalent-Ion-Doped Colloidal CsPb1-xMxBr3 Perovskite Nanocrystals through Cation Exchange.

    Science.gov (United States)

    van der Stam, Ward; Geuchies, Jaco J; Altantzis, Thomas; van den Bos, Karel H W; Meeldijk, Johannes D; Van Aert, Sandra; Bals, Sara; Vanmaekelbergh, Daniel; de Mello Donega, Celso

    2017-03-22

    Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition tuning through topotactic anion exchange. In contrast, property control by cation exchange is still underdeveloped for colloidal CsPbX3 NCs. Here, we present a method that allows partial cation exchange in colloidal CsPbBr3 NCs, whereby Pb(2+) is exchanged for several isovalent cations, resulting in doped CsPb1-xMxBr3 NCs (M= Sn(2+), Cd(2+), and Zn(2+); 0 cells upon incorporation of the guest cations. The partial Pb(2+) for M(2+) exchange leads to a blue-shift of the optical spectra, while maintaining the high photoluminescence quantum yields (>50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. The blue-shift in the optical spectra is attributed to the lattice contraction that accompanies the Pb(2+) for M(2+) cation exchange and is observed to scale linearly with the lattice contraction. This work opens up new possibilities to engineer the properties of halide perovskite NCs, which to date are demonstrated to be the only known system where cation and anion exchange reactions can be sequentially combined while preserving the original NC shape, resulting in compositionally diverse perovskite NCs.

  15. Antiferroelectric instability in the kagome francisites Cu3Bi (SeO3)2O2X (X =Cl ,Br )

    Science.gov (United States)

    Prishchenko, Danil A.; Tsirlin, Alexander A.; Tsurkan, Vladimir; Loidl, Alois; Jesche, Anton; Mazurenko, Vladimir G.

    2017-02-01

    Density-functional calculations of lattice dynamics and high-resolution synchrotron powder diffraction uncover antiferroelectric distortion in the kagome francisite Cu3Bi (SeO3)2O2Cl below 115 K. Its Br-containing analog is stable in the room-temperature crystal structure down to at least 10 K, although the Br compound is on the verge of a similar antiferroelectric instability and reveals local displacements of Cu and Br atoms. The I-containing compound is stable in its room-temperature structure according to density-functional calculations. We show that the distortion involves cooperative displacements of Cu and Cl atoms, and originates from the optimization of interatomic distances for weakly bonded halogen atoms. The distortion introduces a tangible deformation of the kagome spin lattice and may be responsible for the reduced net magnetization of the Cl compound compared to the Br one. The polar structure of Cu3Bi (SeO3)2O2Cl is only slightly higher in energy than the nonpolar antiferroelectric structure, but no convincing evidence of its formation could be obtained.

  16. Highly Emissive Divalent-Ion-Doped Colloidal CsPb1–xMxBr3 Perovskite Nanocrystals through Cation Exchange

    Science.gov (United States)

    2017-01-01

    Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition tuning through topotactic anion exchange. In contrast, property control by cation exchange is still underdeveloped for colloidal CsPbX3 NCs. Here, we present a method that allows partial cation exchange in colloidal CsPbBr3 NCs, whereby Pb2+ is exchanged for several isovalent cations, resulting in doped CsPb1–xMxBr3 NCs (M= Sn2+, Cd2+, and Zn2+; 0 50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. The blue-shift in the optical spectra is attributed to the lattice contraction that accompanies the Pb2+ for M2+ cation exchange and is observed to scale linearly with the lattice contraction. This work opens up new possibilities to engineer the properties of halide perovskite NCs, which to date are demonstrated to be the only known system where cation and anion exchange reactions can be sequentially combined while preserving the original NC shape, resulting in compositionally diverse perovskite NCs. PMID:28260380

  17. The Crystal and Molecular Structure of a New Macrocyclic Ligand, (H6BDBPH)Br6·4H2O

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The hexahydro-bromide salt of a new 24-membered hexaaza diphenol macrocyclic ligand, (H6BDBPH)Br6·4H2O (C26H56N6O6Br6, M, = 1028.23), crystallizes in the monoclinic system, space group P21/c, with cell parameters: a = 14. 441(5), b=11.482(4), c=12.090(6)A, β=96.92°, V= 1990 (1)A3, Z=2, Dc=1. 716 g/cm3; F(000) = 1024. MoKa radiation, λ= 0. 71013A ), R = 0.0643 and wR = 0. 1356 for 3507 independent reflections with I > 2σ (I). The macrocyclic ligand adapts chair form, and the crystallographic inversion center is located in the macrocyclic cavity, and the six bromide ions and four water molecules are situated symmetrically outside the macrocyclic cavity.

  18. A Prototype of LaBr3:Ce in situ Gamma-Ray Spectrometer for Marine Environmental Monitoring

    CERN Document Server

    Zeng, Zhi; Pan, Xingyu; Xue, Tao; Ma, Hao; Yi, Hongchang; Cheng, Jianping

    2015-01-01

    A prototype of LaBr3:Ce in situ gamma-ray spectrometer for marine environmental monitoring is developed and applied for in situ measurement. A 3-inch LaBr3:Ce scintillator is used in the detector, and a digital pulse process electronics is chosen as the pulse height analyzer. For this prototype, the energy response of the spectrometer is linear and the energy resolution of 662keV is 2.6% (much better than NaI). With the measurement of the prototype in a water tank filled with 137Cs, the detect efficiency for 137Cs is (0.288 0.01)cps/(Bq/L), which is close to the result of Monte Carlo simulation, 0.283cps/(Bq/L). With this measurement, the MDAC for 137Cs in one hour has been calculated to 0.78Bq/L, better than that of NaI(Tl) in-situ gamma spectrometer, which is ~1.0Bq/L.

  19. Synthesis and Characterization of (CH3CH2CH2CH2NH3)2SnBr6

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhang-Jing; GUO Guo-Cong; CAI Li-Zhen; ZHOU Guo-Wei; LIU Bing; CHEN Wen-Tong; WU A-Qing; FU Ming-Lai; HUANG Jin-Shun

    2005-01-01

    The title compound ((CH3CH2CH2CH2NH3)2SnBr6, Mr = 746.44) has been synthesized by hydrothermal technique and its crystal structure was determined by X-ray diffraction method. It crystallizes in monoclinic, space group P21/m with a = 10.633(2), b = 7.6152(15), c = 12.633(3) (A), β = 103.25(3)°, V = 995.7(4) (A)3, Z = 2, Dc = 2.490 g/cm3, F(000) = 692, μ(MoKα) = 13.309 mm-1 and T = 293(2) K. The final R = 0.0634 and wR = 0.1236 for 936 observed reflections with I > 2((I). Each tin atom in the present compound is coordinated by six bromine atoms to adopt a slightly distorted octahedral geometry. The interactions between protonated organic amine and [SnBr6]4- anions are electrostatic. The thermogravimetric analysis shows that the compound is not decomposed until 260 ℃. The optical absorption spectrum of the compound reveals the appearance of a sharp optical gap of 2.95 eV, and fluorescence study shows it displays intense blue emission in solid state.

  20. Annealing effects and DLTS study on PNP silicon bipolar junction transistors irradiated by 20 MeV Br ions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chaoming [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Li, Xingji, E-mail: lxj0218@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yang, Jianqun [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Bollmann, Joachim [Institute of Electronics and Sensor Materials, TU Bergakademie, Freiberg 71691 (Germany)

    2014-01-21

    Isochronal anneal sequences have been carried out on 3CG130 silicon PNP bipolar junction transistors (BJTs) irradiated with 20 MeV bromine (Br) heavy ions. The Gummel curve was utilized to characterize the annealing behavior of defects in both the emitter-base depletion region and the neutral base. The results show that the base current (I{sub B}) decreases with the increasing annealing temperature, while the collector current (I{sub C}) keeps invariably. The current gain varies slightly, when the annealing temperature (T{sub A}) is lower than 500 K, while varies rapidly at T{sub A}>550 K, and the current gain of the 3CG130 BJT annealing at 700 K almost restore to that of the pre-radiation transistor. The deep level transient spectroscopy (DLTS) data was used to assign the relative magnitude of each of the important defects. Based on the in situ electrical measurement and DLTS spectra, it is clear that the V{sub 2}(+/0) trap is the main contribution to the degradation of current gain after the 20 MeV Br ions irradiation. The V{sub 2}(+/0) peak has many characteristics expected for the current gain degradation.