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Sample records for bromine 79 target

  1. Bromine

    Czech Academy of Sciences Publication Activity Database

    Pavelka, Stanislav

    2. Weinheim : WileyVCH, 2004 - (Merian, E.; Anke, M.; Ihnat, M.; Stoeppler, M.), s. 1445-1455 ISBN 3-527-30459-2. - (3) Institutional research plan: CEZ:AV0Z5011922 Keywords : bromine * analysis * biological relevance Subject RIV: CA - Inorganic Chemistry

  2. Addition of bromine as a diagnostic gas to inertial confinement fusion target microspheres

    International Nuclear Information System (INIS)

    Currently, direct fuel rho r measurements on Inertial Confinement Fusion (ICF) targets by neutron activation of the argon tracer gas mixed with the DT fuel would require a 100 fold increase in neutron yield. Bromine, on the other hand, has excellent properties for neutron activation analysis at neutron yields of 10two' to 108, when present at an internal pressure of from 0.1 to 0.2 atmospheres. Bromine addition is accomplished in a 2 furnace system using the dried-gel method of microsphere production. An upper furnace operated at 15000C is separated from a lower furnace by a cooled zone. The lower furnace is filled with bromine gas and operated at approximately 12500C. The upper furnace is the glass production furnace. The cooled zone in between the upper and lower furnace is to prevent the hot bromine gas from rising into the upper furnace. The microspheres pass through the cooled zone and immediately into the 12500C bromine furnace where the bromine permeates into the spheres

  3. Bromine Safety

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, B

    2001-04-09

    The production and handling in 1999 of about 200 million kilograms of bromine plus substantial derivatives thereof by Great Lakes Chemical Corp. and Albemarle Corporation in their southern Arkansas refineries gave OSHA Occupational Injury/Illness Rates (OIIR) in the range of 0.74 to 1.60 reportable OIIRs per 200,000 man hours. OIIRs for similar industries and a wide selection of other U.S. industries range from 1.6 to 23.9 in the most recent OSHA report. Occupational fatalities for the two companies in 1999 were zero compared to a range in the U.S.of zero for all computer manufacturing to 0.0445 percent for all of agriculture, forestry and fishing in the most recent OSHA report. These results show that bromine and its compounds can be considered as safe chemicals as a result of the bromine safety standards and practices at the two companies. The use of hydrobromic acid as an electrical energy storage medium in reversible PEM fuel cells is discussed. A study in 1979 of 20 megawatt halogen working fluid power plants by Oronzio de Nora Group found such energy to cost 2 to 2.5 times the prevailing base rate at that time. New conditions may reduce this relative cost. The energy storage aspect allows energy delivery at maximum demand times where the energy commands premium rates. The study also found marginal cost and performance advantages for hydrobromic acid over hydrochloric acid working fluid. Separate studies in the late 70s by General Electric also showed marginal performance advantages for hydrobromic acid.

  4. Direct methylation of FXR by Set7/9, a lysine methyltransferase, regulates the expression of FXR target genes

    OpenAIRE

    Balasubramaniyan, Natarajan; Ananthanarayanan, Meena; Suchy, Frederick J.

    2012-01-01

    The farnesoid X receptor (FXR) is a ligand (bile acid)-dependent nuclear receptor that regulates target genes involved in every aspect of bile acid homeostasis. Upon binding of ligand, FXR recruits an array of coactivators and associated proteins, some of which have intrinsic enzymatic activity that modify histones or even components of the transcriptional complex. In this study, we show chromatin occupancy by the Set7/9 methyltransferase at the FXR response element (FXRE) and direct methylat...

  5. Analysis of X-Ray Appearance in 79 Cases of Breast Cancer by Molybdenum Target Mammography%79例乳腺癌钼靶X线征象分析

    Institute of Scientific and Technical Information of China (English)

    王敏红; 陈方满; 张锡龙; 汪婷; 水海燕; 周理想

    2011-01-01

    Objective To analyze the imaging features of the breast cancer by molybdenum target mammography, in order to improve the diagnostic accuracy. Methods The findings by molybdenum target mammography in 79 cases of breast cancer confinned by surgery and pathology were analyzed retrospectively. Results Among the 79 cases,53 cases showed mass(67.1% ),25 cases appeared burr( 31.6% );31 cases presented malignant calcification (39.3%); 17 cases show non compact nature (21.5%). Conclusion The molybdenum target mammography,with a clear finding,is of great value in the diagnosis of breast cancer, and is preferable in clinic for screening the disease.%目的 通过对乳腺癌钼靶X线征象的分析,提高乳腺癌的诊断正确率.方法 对79例经手术病理证实为乳腺癌患者的钼靶X线征象进行回顾性分析、总结.结果 79例乳腺癌患者X线征象:直接见肿块53例(67.1%),毛刺征25例(31.6%),恶性钙化31例(39.2%),不对称性致密影17例(21.5%).结论 乳腺钼靶摄影对乳腺癌显示清楚,具有较高的诊断正确率,可作为乳腺癌首选的影像学检查方法.

  6. Peculiar and rapid photocatalytic degradation of tetrabromodiphenyl ethers over Ag/TiO2 induced by interaction between silver nanoparticles and bromine atoms in the target.

    Science.gov (United States)

    Lei, Ming; Wang, Nan; Zhu, Lihua; Tang, Heqing

    2016-05-01

    As a typical moderately-brominated diphenylethers, 2,2',4,4'-tetrabromodiphenyl ether (BDE47) is hardly debrominated by a conventional TiO2-mediated photocatalysis. However, its reductive debromination was rapid achieved over silver nanoparticle-loaded TiO2 (Ag/TiO2) in UV-irradiated anoxic acetonitrile-water within 13 min. An "Ag-promoted electron transfer and C-Br cleavage" concept was proposed based on experimental results and density functional theory calculations. Ag(0) exerted affinity interaction with bromine atoms, and the storing of electrons on Ag(0) increased the binding interaction, which elongated the C-Br bond of BDE47 and facilitated its cleavage. The initiating of the BDE47 debromination on Ag(0) required an induction period to enrich a critical amount of electrons, leading to a stronger driving force for both injecting electron to BDE47 and stretching the C-Br bond. Stronger photo-excitation, higher polar solvent, and a moderate Ag(0) load strengthened the interfacial electron transfer over Ag/TiO2, and thereby shortening the induction time and accelerating the BDE47 degradation. PMID:26546118

  7. Accurate measurement of bromine contents in plastic samples by instrumental neutron activation analysis.

    Science.gov (United States)

    Kim, I J; Lee, K S; Hwang, E; Min, H S; Yim, Y H

    2013-03-26

    Accurate measurements of bromine contents in plastic samples were made by the direct comparator instrumental neutron activation analysis (INAA). Individual factors affecting the measurements were comprehensively evaluated and compensated, including the volatility loss of bromine from standard comparators, the background bromine level in the filter papers used for preparation of the standard comparators, nuclear interference, γ-ray spectral interference and the variance among replicates of the samples. Uncertainty contributions from those factors were thoroughly evaluated and included in the uncertainty budgeting of the INAA measurement. (81)Br was chosen as the target isotope, and the INAA measurements for bromine were experimentally confirmed to exhibit good linearity within a bromine content range of 10-170 μg. The established method has been applied to the analysis of eight plastic samples: four commercially available certified reference materials (CRMs) of polyethylene and polystyrene and four acrylonitrile butadiene styrene (ABS) samples prepared as the candidate reference materials (KRISS CRM 113-01-012, -013, -014 and -015). The bromine contents of the samples were calculated at three different γ-ray energies and compared, showing good agreement. The results of the four CRMs also showed good consistency with their certified values within the stated uncertainties. Finally, the bromine contents of the ABS samples were determined with expanded uncertainties (at a 95% level of confidence) between 2.5% and 5% in a bromine content range of 25-900 mg kg(-1). PMID:23498117

  8. Two new brominated diterpenes from Laurencia decumbens

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Two new brominated diterpenes, namely, laurendecumtriol and 11-deacetylpinnaterpene C, were isolated and identified from the marine red alga Laurencia decumbens. Their structures were established on the basis of various NMR spectroscopic techniques and HR-ESI-MS analyses.

  9. Bromine accumulation in acidic black colluvial soils

    Science.gov (United States)

    Cortizas, Antonio Martínez; Vázquez, Cruz Ferro; Kaal, Joeri; Biester, Harald; Casais, Manuela Costa; Rodríguez, Teresa Taboada; Lado, Luis Rodríguez

    2016-02-01

    Recent investigations showed that bromine is incorporated to soil organic matter (SOM), its content increasing with humification. But few research was done on its long-term accumulation and the role played by pedogenetic processes, as those involved in organic matter stabilization. We investigated bromine content and distribution in four deep, acidic, organic-rich, Holocene soils from an oceanic area of Western Europe. Bromine concentrations (93-778 μg g-1) in the silt + clay (area, and total estimated retention was low (6-16%). The degree of SOM bromination, expressed as the Br/C molar ratio, varied between 0.03 and 1.20 mmol Br/mol C. The ratio was highly correlated (n = 23, r2 0.88, p pool of metal-clay-stabilized organic matter.

  10. Microbial degradation of the brominated flame retardant TBNPA by groundwater bacteria: laboratory and field study.

    Science.gov (United States)

    Balaban, Noa; Bernstein, Anat; Gelman, Faina; Ronen, Zeev

    2016-08-01

    In the present study, the biodegradation of the brominated flame retardant tribromoneopentylalcohol (TBNPA) by a groundwater enrichment culture was investigated using a dual carbon ((13)C/(12)C)- bromine ((81)Br/(79)Br) stable isotope analysis. An indigenous aerobic bacterial consortium was enriched from the polluted groundwater underlying an industrial site in the northern Negev Desert, Israel, where TBNPA is an abundant pollutant. Aerobic biodegradation was shown to be rapid, with complete debromination within a few days, whereas anaerobic biodegradation was not observed. Biodegradation under aerobic conditions was accompanied by a significant carbon isotope effect with an isotopic enrichment factor of ɛCbulk = -8.8‰ ± 1.5‰, without any detectable bromine isotope fractionation. It was found that molecular oxygen is necessary for biodegradation to occur, suggesting an initial oxidative step. Based on these results, it was proposed that H abstraction from the C-H bond is the first step of TBNPA biodegradation under aerobic conditions, and that the C-H bond cleavage results in the formation of unstable intermediates, which are rapidly debrominated. A preliminary isotopic analysis of TBNPA in the groundwater underlying the industrial area revealed that there are no changes in the carbon and bromine isotope ratio values downstream of the contamination source. Considering that anoxic conditions prevail in the groundwater of the contaminated site, the lack of isotope shifts in TBNPA indicates the lack of TBNPA biodegradation in the groundwater, in accordance with our findings. PMID:27183339

  11. Bromine-77-labeled estrogen receptor-binding radiopharmaceuticals for breast tumor imaging

    International Nuclear Information System (INIS)

    Two derivatives of 16α-bromoestradiol, both with and without an 11β-methoxy substituent, have been labeled with bromine-77 and evaluated as potential breast tumor imaging agents. Extensive characterization of these radiotracers in animal models has demonstrated their effective concentration in estrogen target tissues. Preliminary clinical studies have demonstrated the potential of radiolabeled estrogens for breast tumor imaging; however, the suboptimal decay properties of bromine-77 limit the utility of these agents in imaging studies. These results with 77-Br-labeled estrogens suggest that estrogen derivatives labeled with other radionuclides should provide enhanced image resolution with various imaging devices. Although the decay characteristics of bromine-77 are such that it is not ideally suited to imaging with conventional gamma cameras, it may be a useful radionuclide for therapeutic applications

  12. 40 CFR 721.3085 - Brominated phthalate ester.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Brominated phthalate ester. 721.3085... Substances § 721.3085 Brominated phthalate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as brominated phthalate ester (PMN P-90-581)...

  13. 40 CFR 721.9740 - Brominated triazine derivative.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Brominated triazine derivative. 721... Substances § 721.9740 Brominated triazine derivative. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a brominated triazine...

  14. Simultaneous production of high-pure 76Br, 77Br and 79Kr using an isotope separator

    International Nuclear Information System (INIS)

    A production method of the bromine radioisotopes 76Br and 77Br in high radiochemical purity has been developed without using an isotopically enriched target, instead, their precursors 76Kr and 77Kr produced in a NaBr target by proton irradiation were mass-separated and implanted into Al foils together with 79Kr by means of a high-resolution isotope separator. The isotope separation efficiencies of the radiokryptons with a compact ECR ion source were found to be 15±2%. The 79Kr was recovered cryogenically from the Al foil heated, while 76Kr and 77Kr were allowed to decay for 14.6 h and 1.24 h, respectively during which the almost maximum growth of 76Br and 77Br occurred. A comparison was made between anion and cation exchange methods for chemical separation of the radiobromines from the Al foils. The recovery efficiencies were found to be almost identical between then, and better than 95%. (author)

  15. Hormonal activities of new brominated flame retardants

    Czech Academy of Sciences Publication Activity Database

    Ezechiáš, Martin; Svobodová, Kateřina; Cajthaml, Tomáš

    2012-01-01

    Roč. 87, č. 7 (2012), s. 820-824. ISSN 0045-6535 R&D Projects: GA ČR GA104/09/0694 Institutional research plan: CEZ:AV0Z50200510 Keywords : Brominated flame retardants * 2,4,6-Tribromophenol * Endocrine disruptors Subject RIV: EE - Microbiology, Virology Impact factor: 3.137, year: 2012

  16. Brominated dioxins and dibenzofurans in human adipose tissue. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, P.H.; Stanley, J.S.; Bauer, K.; Ayling, R.E.; Thornburg, K.R.

    1990-04-11

    The report describes the analytical efforts for the determination of polybrominated dioxins (PBDDs) and furans (PBDFs) in human adipose tissues. Data on the precision and accuracy of the method for three tetra- through hexabrominated dioxins and three tetra- through hexabrominated furans (specific 2,3,7,8-substituted isomers) were generated from the analysis of 5 unspiked and 10 spiked (5 replicates at 2 spike levels) adipose tissue samples that were included with the analysis of the FY 1987 samples. In addition, data are presented on the results of the analysis of 48 composite samples for the six specific PBDD and PBDF compounds. The targeted 2,3,7,8-substituted PBDDs and PBDFs were not detected in any of the samples except those prepared as spiked QC materials. The detection limits calculated for the tetrabromo congeners in the samples ranged from 0.46 to 8.9 pg/g (lipid basis). The detection limits for the higher brominated congeners were typically greater than that observed for the tetrabrominated compounds. There is some evidence for the presence of other brominated compounds in the adipose tissue samples. Specifically, responses were noted that correspond to the qualitative criteria for polybrominated diphenyl ethers (hexa through octabromo).

  17. Symproportionation versus Disproportionation in Bromine Redox Systems

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted -- Highlights: • The disproportionation and symproportionation of bromine in different media is presented. • All the redox systems are elaborated according to the principles of the generalized approach to electrolytic redox systems (GATES/GEB). • All physicochemical knowledge is involved in the algorithm applied for this purpose. • The graphical representation of the systems is the basis of gaining the detailed physicochemical knowledge on the systems in question. -- Abstract: The paper refers to dynamic (titration) redox systems where symproportionation or disproportionation of bromine species occur. The related systems are modeled according to principles assumed in the Generalized Approach to Electrolytic Redox Systems (GATES), with Generalized Electron Balance (GEB) concept involved in the GATES/GEB software. The results obtained from calculations made with use of iterative computer programs prepared according to MATLAB computational software, are presented graphically, as 2D and 3D graphs

  18. Membrane-less hydrogen bromine flow battery

    CERN Document Server

    Braff, W A; Buie, C R

    2014-01-01

    In order for the widely discussed benefits of flow batteries for electrochemical energy storage to be applied at large scale, the cost of the electrochemical stack must come down substantially. One promising avenue for reducing stack cost is to increase the system power density while maintaining efficiency, enabling smaller stacks. Here we report on a membrane-less, hydrogen bromine laminar flow battery as a potential high power density solution. The membrane-less design enables power densities of 0.795 W cm$^{-2}$ at room temperature and atmospheric pressure, with a round-trip voltage efficiency of 92\\% at 25\\% of peak power. Theoretical solutions are also presented to guide the design of future laminar flow batteries. The high power density achieved by the hydrogen bromine laminar flow battery, along with the potential for rechargeable operation, will translate into smaller, inexpensive systems that could revolutionize the fields of large-scale energy storage and portable power systems.

  19. Brominated flame retardants and endocrine disruption

    OpenAIRE

    Vos, J G; Becher, G; Berg, van den, C.A.; Boer; Leonards, P.E.G.

    2003-01-01

    From an environmental point of view, an increasing important group of organohalogen compounds are the brominated flame retardants (BFRs), which are widely used in polymers and textiles and applied in construction materials, furniture, and electronic equipment. BFRs with the highest production volume are the polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBP-A), and hexabromocyclododecane (HBCD). Because of their persistence and low biodegradation profile, several of the PBDE ...

  20. Brominated thiophenes as precursors in the preparation of brominated and arylated anthraquinones.

    Science.gov (United States)

    Thiemann, Thies; Tanaka, Yasuko; Iniesta, Jesus

    2009-01-01

    Brominated anthraquinones can be synthesized directly from bromothiophenes when these are reacted with 1,4-naphthoquinones in the presence of meta-chloroperoxybenzoic acid. The bromoanthraquinones are versatile building blocks in the preparation of arylated anthraquinones and of extended pi-systems with interspersed anthraquinone units. PMID:19305356

  1. Brominated Thiophenes as Precursors in the Preparation of Brominated and Arylated Anthraquinones

    Directory of Open Access Journals (Sweden)

    Thies Thiemann

    2009-03-01

    Full Text Available Brominated anthraquinones can be synthesized directly from bromothiophenes when these are reacted with 1,4-naphthoquinones in the presence of meta-chloroperoxybenzoic acid. The bromoanthraquinones are versatile building blocks in the preparation of arylated anthraquinones and of extended π-systems with interspersed anthraquinone units.

  2. Brominated Thiophenes as Precursors in the Preparation of Brominated and Arylated Anthraquinones

    OpenAIRE

    Thies Thiemann; Jesus Iniesta; Yasuko Tanaka

    2009-01-01

    Brominated anthraquinones can be synthesized directly from bromothiophenes when these are reacted with 1,4-naphthoquinones in the presence of meta-chloroperoxybenzoic acid. The bromoanthraquinones are versatile building blocks in the preparation of arylated anthraquinones and of extended π-systems with interspersed anthraquinone units.

  3. The BRomine, Ozone, and Mercury EXperiment (BROMEX)

    Science.gov (United States)

    Nghiem, S. V.; Shepson, P. B.; Simpson, W. R.; Perovich, D. K.; Sturm, M.; Douglas, T. A.; Rigor, I. G.; Clemente-Colon, P.; Burrows, J. P.; Richter, A.; Bottenheim, J. W.; Steffen, A.; Barber, D. G.; Kaleschke, L.; Hall, D. K.; Markus, T.; Eicken, H.; Neumann, G.

    2011-12-01

    In the decade of the 2000s, Arctic perennial (multi-year) sea ice has diminished drastically, whereas seasonal (first-year) sea ice has become the dominant ice class. This change effectively increases the overall surface salinity of the sea ice cover and in the overlying snowpack. Satellite results in 2010 and 2011 show the extent of perennial sea ice remains minimal with significant bromine explosions in the springtime. Key science questions still remain to be answered to understand the impact of the Arctic perennial sea ice reduction on low-atmospheric physical and chemical processes. Of the highest priority is to investigate the impact on bromine explosion events that lead to depletion of ozone and gaseous elementary mercury in the atmosphere. With that objective, we present the development of the BRomine, Ozone, and Mercury EXperiment in (BROMEX) in spring 2012 around Barrow, extending out to 200 km offshore and inland. In BROMEX, chemical, sea ice, snow, and ocean measurements will be made across sea ice leads both upwind and downwind areas of newly opened leads. Chemical-measurement buoys and other types of buoys will be deployed with helicopter flights to both sides of the leads. Various flight patterns of aircraft carrying ozone and bromine-measuring sensors will be used to characterize the chemical distribution over sea ice, land, and mountainous regions. Our approach will use data from multiple satellite instruments including MODIS, AMSR-E, QuikSCAT, GOME-2, SCIAMACHY, OMI, RADARSAT-2, Envisat ASAR, TerraSAR-X, TanDEM-X, SMOS, CryoSat-2 altimeter, and Oceansat-2 scatterometer. Moreover, results from recent field campaigns such as the IPY OASIS, INCATPA, CFL, SALT, and IceBridge, from sea ice and snow products generated by the U.S. Naval and National Ice Center, from NASA cryospheric observations, and from surface observation networks such as SIZONet will be utilized together with new measurements from BROMEX. Further collaborations with the international

  4. Effects of Assistant Solvents and Mixing Intensity on the Bromination Process of Butyl Rubber

    Institute of Scientific and Technical Information of China (English)

    王伟; 邹海魁; 初广文; 向阳; 彭晗; 陈建峰

    2014-01-01

    A slow bromination process of butyl rubber (IIR) suffers from low efficiency and low selectivity (S) of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixing inten-sity on the bromination process were systemically studied in this paper. The reaction process was found constantly accelerated with the increasing dosage and polarity of assistant solvent. Hexane with 30%(by volume) dichloro-methane was found as the suitable solvent component, where the stable conversion of 1,4-isoprene transferring to target product (xA1s) of 80.2%and the corresponding S of 91.2%were obtained in 5 min. The accelerated reaction process was demonstrated being remarkably affected by mixing intensity until the optimal stirring rate of 1100 r·min-1 in a stirred tank reactor. With better mixing condition, a further intensification of the process was achieved in a ro-tating packed bed (RPB) reactor, where xA1s of 82.6% and S of 91.9% were obtained in 2 min. The usage of the suitable solvent component and RPB has potential application in the industrial bromination process intensification.

  5. Formation of THMs and HANs during bromination of Microcystis aeruginosa

    Institute of Scientific and Technical Information of China (English)

    Yunzhu Pu; Lingzhao Kong; Xin Huang; Guoji Ding; Naiyun Gao

    2013-01-01

    Bromine-contained disinfectants and biocides are widely used in swimming pools,recreational waters and cooling towers.The objective of this study was to evaluate the formation of thrihalomethanes (THMs) and haloacetonitriles (HANs) and their cytotoxicity in algae solutions during free bromine disinfection.Disinfection by-products formation potential experiments were conducted using modelsolutions containing 7mg/L (as total organic carbon) Microcystis aeruginosa cells.Effects of free bromine dosage,pH and ammonia were investigated.The results showed that brominated disinfection by-products were the major products when free bromine was applied.The total THMs formed during bromination was much as that formed during chlorination,whereas HANs were elevated by using bromination instead of chlorination.Dibromoacetonitrice (C2H2NBr2) and bromoform (CHBr3) were the only detected species during free bromine disinfection.The production of C2H2NBr2 and CHBr3 increased with disinfectant dosage but decreased with dosing ammonia.CHBr3 increased with the pH changing from 5 to 9.However,C2H2NBr2 achieved the highest production at neutral pH,which was due to a joint effect of variation in hydrolysis rate and free bromine reactivity.The hydrolysis of C2H2NBr2 was basecatalytic and nearly unaffected by disinfectant.Finally,estimation of cytotoxicity of the disinfected algae solutions showed that HANs formation was responsible for the majority of toxicity.Considering its highest toxicity among the measured disinfection by-products,the elevated C2H2NBr2 should be considered when using bromine-related algaecide.

  6. New infrared spectroscopic database for bromine nitrate

    Science.gov (United States)

    Wagner, Georg; Birk, Manfred

    2016-08-01

    Fourier transform infrared measurements of bromine nitrate have been performed in the spectral region 675-1400 cm-1 at 0.014 cm-1 spectral resolution. Absorption cross sections were derived from 38 spectra covering the temperature range from 203 to 296 K and air pressure range from 0 to 190 mbar. For line-by-line analysis, further spectra were recorded at 0.00094 cm-1 spectral resolution at 223 and 293 K. The sample was synthesized from ClONO2 and Br2. Band strengths of the bands ν3 around 803 cm-1 and ν2 around 1286 cm-1 were determined from three pure BrONO2 measurements at different temperatures and pressures. Number densities in the absorption cell were derived from pressure measurements of the purified sample taking into account small amounts of impurities determined spectroscopically. Resulting band strengths are Sν3 = 2.872(52) × 10-17 cm2 molec-1 cm-1 and Sν2 = 3.63(15) × 10-17 cm2 molec-1 cm-1. Absorption cross sections of all measurements were scaled to these band strengths. Further data reduction was achieved with an interpolation scheme based on two-dimensional polynomials in ln(pressure) and temperature. The database is well-suited for remote-sensing application and should reduce the atmospheric bromine nitrate error budget substantially.

  7. Effect of Bromine Substitution on Human Dermal Absorption of Polybrominated Diphenyl Ethers.

    Science.gov (United States)

    Abdallah, Mohamed Abou-Elwafa; Pawar, Gopal; Harrad, Stuart

    2015-09-15

    Human dermal absorption of eight mono- to deca-brominated diphenyl ethers (PBDEs) was investigated for the first time using EPISKIN human skin equivalent tissue. Using a standard in vitro protocol, EPISKIN tissues mounted in specially designed diffusion cells were exposed to the target PBDEs for 24 h. Estimated steady-state flux (Jss) and permeation coefficients (Papp) across the skin increased with decreasing bromine substitution from BDE-153 (Papp = 4.0 × 10(-4) cm/h) to BDE-1 (Papp = 1.1 × 10(-2) cm/h). This was accompanied by an increase in the time required to traverse the skin tissue into the receptor fluid (lag time) from 0.25 h for BDE-1 to 1.26 h for BDE-153. Papp values for the studied PBDEs were correlated significantly (P water solubility and log KOW. While less brominated congeners achieved faster dermal penetration, higher PBDEs displayed greater accumulation within the skin tissue. The PBDEs thus accumulated represent a contaminant depot from which they may be slowly released to the systemic circulation over a prolonged period. Maximal percutaneous penetration was observed for BDE-1 (∼ 30% of the applied 500 ng/cm(2) dose). Interestingly, BDE-183 and BDE-209 showed very low dermal absorption, exemplified by a failure to reach the steady state within the 24 h exposure period that was studied. PMID:26301594

  8. Ruthenium-Catalyzed meta-Selective C—H Bromination

    Science.gov (United States)

    Teskey, Christopher J; Lui, Andrew Y W; Greaney, Michael F

    2015-01-01

    The first example of a transition-metal-catalyzed, meta-selective C–H bromination procedure is reported. In the presence of catalytic [{Ru(p-cymene)Cl2}2], tetrabutylammonium tribromide can be used to functionalize the meta C–H bond of 2-phenylpyridine derivatives, thus affording difficult to access products which are highly predisposed to further derivatization. We demonstrate this utility with one-pot bromination/arylation and bromination/alkenylation procedures to deliver meta-arylated and meta-alkenylated products, respectively, in a single step. PMID:26288217

  9. Ruthenium-Catalyzed meta-Selective C—H Bromination

    OpenAIRE

    Teskey, Christopher J; Lui, Andrew Y W; Greaney, Michael F.

    2015-01-01

    The first example of a transition-metal-catalyzed, meta-selective C–H bromination procedure is reported. In the presence of catalytic [{Ru(p-cymene)Cl2}2], tetrabutylammonium tribromide can be used to functionalize the meta C–H bond of 2-phenylpyridine derivatives, thus affording difficult to access products which are highly predisposed to further derivatization. We demonstrate this utility with one-pot bromination/arylation and bromination/alkenylation procedures to deliver meta-arylated and...

  10. Magnetic Trapping of Cold Bromine Atoms

    CERN Document Server

    Rennick, C J; Doherty, W G; Softley, T P

    2014-01-01

    Magnetic trapping of bromine atoms at temperatures in the milliKelvin regime is demonstrated for the first time. The atoms are produced by photodissociation of Br$_2$ molecules in a molecular beam. The lab-frame velocity of Br atoms is controlled by the wavelength and polarization of the photodissociation laser. Careful selection of the wavelength results in one of the pair of atoms having sufficient velocity to exactly cancel that of the parent molecule, and it remains stationary in the lab frame. A trap is formed at the null point between two opposing neodymium permanent magnets. Dissociation of molecules at the field minimum results in the slowest fraction of photofragments remaining trapped. After the ballistic escape of the fastest atoms, the trapped slow atoms are only lost by elastic collisions with the chamber background gas. The measured loss rate is consistent with estimates of the total cross section for only those collisions transferring sufficient kinetic energy to overcome the trapping potential...

  11. The metabolism and de-bromination of bromotyrosine in vivo

    NARCIS (Netherlands)

    A.R. Mani (Ali); J.C. Moreno (José C.); T.J. Visser (Theo J.); K.P. Moore (Kevin P.)

    2016-01-01

    textabstractDuring inflammation, leukocyte-derived eosinophil peroxidase catalyses the formation of hypobromous acid, which can brominate tyrosine residues in proteins to form bromotyrosine. Since eosinophils are involved in the pathogenesis of allergic reactions, such as asthma, urinary bromotyrosi

  12. Bromine number should replace FIA in gasoline olefins testing

    International Nuclear Information System (INIS)

    Fluorescent indicator adsorption (FIA) analysis, the ASTM test method proposed by the U.S. Environmental Protection Agency (EPA) for monitoring olefins in reformulated gasoline, is subject to significant bias and imprecision. This paper reports on a more accurate, environmentally pertinent measure of olefin content in reformulated gasoline is bromine number another ASTM method. Petroleum chemists should therefore work together with the EPA to select and optimize a bromine number procedure specifically designed for reformulated gasoline to replace FIA

  13. A comparison of the in vitro cyto- and neurotoxicity of brominated and halogen-free flame retardants : prioritization in search for safe(r) alternatives

    NARCIS (Netherlands)

    Hendriks, Hester S; Meijer, Marieke; Muilwijk, Mirthe; van den Berg, Martin; Westerink, Remco H S

    2014-01-01

    Brominated flame retardants (BFRs) are abundant persistent organic pollutants with well-studied toxicity. The toxicological and ecological concerns associated with BFRs argue for replacement by safe(r) alternatives. Though previous research identified the nervous system as a sensitive target organ f

  14. Probing the tropical tropopause layer for organic and inorganic bromine

    Science.gov (United States)

    Werner, Bodo; Pfeilsticker, Klaus; Atlas, Elliot; Cheung, Ross; Chipperfield, Martyn; Colosimo, Fedele; Deutschmann, Tim; Elkins, Jim; Fahey, David; Feng, Wu; Festa, James; Gao, Ru-Shan; Hossaini, Ryan; Navarro, Maria; Raecke, Rasmus; Scalone, Lisa; Spolaor, Max; Thornberry, Troy; Tsai, Catalina; Stutz, Jochen

    2016-04-01

    Bromine chemistry impacts the levels of ozone in the upper troposphere and the stratosphere. An accurate quantitative understanding of the sources, sinks, and chemical transformation of bromine species is thus important to understand the photochemistry and budget of bromine in the tropical upper troposphere, tropopause layer and lowermost stratosphere (UT/TTL/LS). These regions are also known to serve as a gateway for delivery of ozone depleting gases to the stratosphere. CH3Br, halons, short-lived organic bromine precursors (VSLS), such as CHBr3, CH2Br2, and possibly inorganic product gases have been identified as the main bromine gases delivered to the stratosphere. However, many important details of the transport and delivery of VSLS and inorganic bromine compounds through the TTL are still uncertain. Moreover, a number of chemical processes, including the transformation of the source gases and cycling of inorganic bromine species at low ambient temperature and on ice particles are also poorly understood. The presentation reports measurements of CH4, O3, NO2, and BrO performed by different instruments and techniques during the 2013 NASA-ATTREX flights in the TTL and LS. The interpretation of our measurements is supported by chemical transport model (SLIMCAT) simulations. SLIMCAT results, in conjunction with extensive radiative transfer calculations using the Monte Carlo model McArtim, also are used to improve retrieval of O3, NO2, and BrO concentrations from limb scattered sunlight measurements made with the Differential Optical Absorption Spectroscopy (DOAS) technique during ATTREX. The chemical transport model also allows us to attribute observed concentration variations to transport and to photochemical processes. When properly accounting for the transport-related concentration variations in methane and ozone, we find that measured BrO mostly agrees with model simulations. An exception are regions where the contribution of the short-lived CH2Br2 or the

  15. Bromine pretreated chitosan for adsorption of lead (II) from water

    Indian Academy of Sciences (India)

    Rajendra Dongre; Minakshi Thakur; Dinesh Ghugal; Jostna Meshram

    2012-10-01

    Pollution by heavy metals like lead (II) is responsible for health hazards and environmental degradation. Adsorption is a prevalent method applied for removal of heavy metal pollutants from water. This study explored adsorption performances of 30% bromine pretreated chitosan for lead (II) abatement from water. Bromine pretreatment alters porosity and specific surface area of chitosan by means of physicochemical interaction with cationic sites of chitosan skeleton, besides imparting anionic alteration at amino linkages of chitosan, to remove lead (II) by chemical interactions on superfluous active sites as characterized by FTIR, SEM, DTA and elemental analysis. Lead adsorptions were studied in batch mode by varying parameters viz. pH, bromine loading, sorbent dosage, initial lead concentration, contact time and temperature. The adsorption equilibrium data was well fitted to Freundlich isotherm and maximum sorption capacity of 30% bromine pretreated chitosan sorbent was 1.755 g/kg with 85–90% lead removal efficiency. Though cost and applicability of sorbent is unproven, yet contrast to raw chitosan derivatives, activated carbons and some resins, 30% bromine pretreated chitosan endow benign and efficient lead abatement technique.

  16. Levels and trends of brominated flame retardants in the European environment

    NARCIS (Netherlands)

    Law, R.J.; Allchin, C.R.; Boer, de J.; Covaci, A.; Herzke, D.; Lepom, P.; Morris, S.; Tronczynski, J.; Wit, de C.A.

    2006-01-01

    In this paper, we review those data which have recently become available for brominated flame retardants (particularly the brominated diphenyl ethers (BDEs) and hexabromocyclododecane (HBCD)) in samples from the European environment. Environmental compartments studied comprise the atmosphere, sedime

  17. An Efficient and Facile Methodology for Bromination of Pyrimidine and Purine Nucleosides with Sodium Monobromoisocyanurate (SMBI

    Directory of Open Access Journals (Sweden)

    Roger Stromberg

    2013-10-01

    Full Text Available An efficient and facile strategy has been developed for bromination of nucleosides using sodium monobromoisocyanurate (SMBI. Our methodology demonstrates bromination at the C-5 position of pyrimidine nucleosides and the C-8 position of purine nucleosides. Unprotected and also several protected nucleosides were brominated in moderate to high yields following this procedure.

  18. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bromide ion and residual bromine... Tolerances § 180.519 Bromide ion and residual bromine; tolerances for residues. (a) General. The food additives, bromide ion and residual bromine, may be present in water, potable in accordance with...

  19. Speciation of the bio-available iodine and bromine forms in edible seaweed by high performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Romaris-Hortas, Vanessa; Bermejo-Barrera, Pilar [Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n. 15782 - Santiago de Compostela (Spain); Moreda-Pineiro, Jorge [Department of Analytical Chemistry, Faculty of Sciences, University of A Coruna, Campus da Zapateira, s/n. 15071, A Coruna (Spain); Moreda-Pineiro, Antonio, E-mail: antonio.moreda@usc.es [Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n. 15782 - Santiago de Compostela (Spain)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer Bioavailable iodine and bromine speciation in edible seaweed were developed. Black-Right-Pointing-Pointer In vitro dialyzability was used to assess the bioavailable fractions. Black-Right-Pointing-Pointer AEC hyphenated with inductively coupled plasma-mass spectrometry was used. Black-Right-Pointing-Pointer Iodide, MIT, DIT, bromide and bromate were found in dialyzates from edible seaweed. Black-Right-Pointing-Pointer Positive correlation between bioavailability and protein contents was found. - Abstract: A bioavailability study based on an in vitro dialyzability approach has been applied to assess the bio-available fractions of iodine and bromine species from edible seaweed. Iodide, iodate, 3-iodo-tyrosine (MIT), 3,5-diiodo-tyrosine (DIT), bromide and bromate were separated by anion exchange chromatography under a gradient elution mode (175 mM ammonium nitrate plus 15% (v/v) methanol, pH 3.8, as a mobile phase, and flow rates within the 0.5-1.5 mL min{sup -1} range). Inductively coupled plasma-mass spectrometry (ICP-MS) was used as a selective detector for iodine ({sup 127}I) and bromine ({sup 79}Br). Low dialyzability ratios (within the 2.0-18% range) were found for iodine species; whereas, moderate dialyzability percentages (from 9.0 to 40%) were obtained for bromine species. Iodide and bromide were the major species found in the dialyzates from seaweed, although MIT and bromate were also found in the dialyzates from most of the seaweed samples analysed. However, DIT was only found in dialyzates from Wakame, Kombu, and NIES 09 (Sargasso) certified reference material; whereas, iodate was not found in any dialyzate. Iodine dialyzability was found to be dependent on the protein content (negative correlation), and on the carbohydrate and dietary fibre levels (positive correlation). However, bromine dialyzability was only dependent on the protein amount in seaweed (negative correlation).

  20. Speciation of the bio-available iodine and bromine forms in edible seaweed by high performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry

    International Nuclear Information System (INIS)

    Highlights: ► Bioavailable iodine and bromine speciation in edible seaweed were developed. ► In vitro dialyzability was used to assess the bioavailable fractions. ► AEC hyphenated with inductively coupled plasma-mass spectrometry was used. ► Iodide, MIT, DIT, bromide and bromate were found in dialyzates from edible seaweed. ► Positive correlation between bioavailability and protein contents was found. - Abstract: A bioavailability study based on an in vitro dialyzability approach has been applied to assess the bio-available fractions of iodine and bromine species from edible seaweed. Iodide, iodate, 3-iodo-tyrosine (MIT), 3,5-diiodo-tyrosine (DIT), bromide and bromate were separated by anion exchange chromatography under a gradient elution mode (175 mM ammonium nitrate plus 15% (v/v) methanol, pH 3.8, as a mobile phase, and flow rates within the 0.5–1.5 mL min−1 range). Inductively coupled plasma-mass spectrometry (ICP-MS) was used as a selective detector for iodine (127I) and bromine (79Br). Low dialyzability ratios (within the 2.0–18% range) were found for iodine species; whereas, moderate dialyzability percentages (from 9.0 to 40%) were obtained for bromine species. Iodide and bromide were the major species found in the dialyzates from seaweed, although MIT and bromate were also found in the dialyzates from most of the seaweed samples analysed. However, DIT was only found in dialyzates from Wakame, Kombu, and NIES 09 (Sargasso) certified reference material; whereas, iodate was not found in any dialyzate. Iodine dialyzability was found to be dependent on the protein content (negative correlation), and on the carbohydrate and dietary fibre levels (positive correlation). However, bromine dialyzability was only dependent on the protein amount in seaweed (negative correlation).

  1. Brominated Dioxins: Little-Known New Health Hazards - A Review

    Directory of Open Access Journals (Sweden)

    Piskorska-Pliszczyńska Jadwiga

    2014-10-01

    Full Text Available This article reviews the present state of the science concerning the polybrominated dibenzo-p-dioxins (PBDDs and dibenzofurans (PBDFs. Everywhere in the world people are exposed to anthropogenic origin chemicals. Some of them are long-lived organic compounds, which persist over the years in the environment. Persistent organic pollutants, such as organohalogen compounds, accumulate in environmental and biological compartments and have adverse effects on the health of humans and animals. Little is known about the brominated and mixed chloro/bromo dioxin and furans. Existing literature suggests that brominated dioxins and furans have similar toxicity profiles to their chlorinated analogues. The exposure data are extremely limited, showing a major data gap in estimating the potential environmental and health risk of these chemicals. The rapid increase in the use of brominated flame retardants (the main source of these pollutants has raised the level of concern over environmental and health damage from brominated dioxins and furans. It is likely that human as well as wildlife exposure to these contaminants will increase with their greater use. The findings reported here present strong evidence of the PBDDs and PBDFs as an emerging new class of contaminants.

  2. Ecotoxicity and biodegradability of new brominated flame retardants: A review

    Czech Academy of Sciences Publication Activity Database

    Ezechiáš, Martin; Covino, Stefano; Cajthaml, Tomáš

    2014-01-01

    Roč. 110, č. 2 (2014), s. 153-167. ISSN 0147-6513 R&D Projects: GA MŠk(CZ) EE2.3.30.0003; GA TA ČR TE01020218 Institutional support: RVO:61388971 Keywords : Ecotoxicity * brominated flame retardants * biodegradation * review Subject RIV: EE - Microbiology, Virology Impact factor: 2.762, year: 2014

  3. Discovery of Zinc, Selenium, Bromine, and Neodymium Isotopes

    OpenAIRE

    J.L. Gross; Claes, J.; Kathawa, J.; Thoennessen, M

    2010-01-01

    Currently, thirty-two zinc, thirty-two selenium, twenty-nine bromine and thirty-one neodymium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  4. 21 CFR 180.30 - Brominated vegetable oil.

    Science.gov (United States)

    2010-04-01

    ... “Food Chemicals Codex,” 3d Ed. (1981), pp. 40-41, which is incorporated by reference, except that free... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Brominated vegetable oil. 180.30 Section 180.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  5. Discovery of zinc, selenium, bromine, and neodymium isotopes

    International Nuclear Information System (INIS)

    Currently, thirty-two zinc, thirty-two selenium, twenty-nine bromine, and thirty-one neodymium isotopes have been observed and the discovery of these isotopes is described here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  6. Bromine provides new weapons to combat mercury emissions

    Energy Technology Data Exchange (ETDEWEB)

    Hardtke, W. [Albermarle Europe (Germany)

    2011-04-15

    Brominated powdered activated carbon has been demonstrated to capture over 90% of mercury emissions from coal fired plants, operating at high temperatures and capturing the metal in concrete-friendly, non-leaching forms to help tackle a rising global health threat. 6 refs., 5 figs.

  7. Bromine measurements in ozone depleted air over the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    J. A. Neuman

    2010-07-01

    Full Text Available In situ measurements of ozone, photochemically active bromine compounds, and other trace gases over the Arctic Ocean in April 2008 are used to examine the chemistry and geographical extent of ozone depletion in the arctic marine boundary layer (MBL. Data were obtained from the NOAA WP-3D aircraft during the Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC study and the NASA DC-8 aircraft during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS study. Fast (1 s and sensitive (detection limits at the low pptv level measurements of BrCl and BrO were obtained from three different chemical ionization mass spectrometer (CIMS instruments, and soluble bromide was measured with a mist chamber. The CIMS instruments also detected Br2. Subsequent laboratory studies showed that HOBr rapidly converts to Br2 on the Teflon instrument inlets. This detected Br2 is identified as active bromine and represents a lower limit of the sum HOBr + Br2. The measured active bromine is shown to likely be HOBr during daytime flights in the arctic. In the MBL over the Arctic Ocean, soluble bromide and active bromine were consistently elevated and ozone was depleted. Ozone depletion and active bromine enhancement were confined to the MBL that was capped by a temperature inversion at 200–500 m altitude. In ozone-depleted air, BrO rarely exceeded 10 pptv and was always substantially lower than soluble bromide that was as high as 40 pptv. BrCl was rarely enhanced above the 2 pptv detection limit, either in the MBL, over Alaska, or in the arctic free troposphere.

  8. Why does bromine square palladium off? An ab initio study of brominated palladium and its nanomorphology.

    Science.gov (United States)

    Yoo, Su-Hyun; Lee, Ji-Hwan; Delley, Bernard; Soon, Aloysius

    2014-09-14

    A first-principles description and prediction of brominated nanocrystals of Pd is presented. In particular, we conducted an extensive study of the adsorption behaviour of Br on various Pd surfaces (including both low and high Miller-index surfaces) as a function of its surface coverage. By coupling our calculated surface energies with ab initio (electrochemical) thermodynamics and the Gibbs-Wulff shape model, we find that the relative stability of the Pd surfaces is strongly modified by Br, allowing high Miller-index surfaces of Pd (namely the (210) surface) to become competitively favourable at moderate concentrations of Br. We also show that Pd nanoparticles assume a cube-like crystal shape at high concentrations of Br, exposing mainly the (100) facets with a Br surface coverage of 0.5 ML. This not only confirms and explains recent solution synthesis results, but also provides a quantitative atomic picture of the exposed surface facets, which is crucial in understanding the local surface chemistry of shape-controlled nanoparticles for better nanocatalyst design. PMID:25075669

  9. Occurrence of bromine in fluidised bed combustion of solid recovered fuel

    Energy Technology Data Exchange (ETDEWEB)

    Vainikka, P.

    2011-12-15

    Corrosive ash species are the single most important factor limiting the electric efficiency of steam boiler plants fired with waste or biomass. Chlorine has been found to have a central role in the chemistry involved as it reduces the melting temperature of ash, forms corrosive vapour and gas species in the furnace and halogenated deposits on boiler heat transfer surfaces. In this context chlorine has been extensively researched. At the time of writing this thesis there was hardly any published data available on the occurrence of bromine (Br) in the aforementioned context. The objective of this work was to review the occurrence of bromine in solid fuels and characterise the behaviour of bromine in full-scale fluidised bed combustion. The review on the occurrence of bromine in solid fuels revealed that in anthropogenic wastes bromine is mainly found in connection to flame retarded substances. Several weight percentages of bromine can be found in plastics treated with brominated flame retardants (BFRs). Bromine is typically found some 100-200 mg kg-1 in mixed municipal solid wastes (MSW). Bromine may be enriched in fuels with high share of plastics, such as solid recovered fuel (SRF) or refuse derived fuel (RDF). Up to 2000 mg kg-1 was found as a monthly average in SRF, typical levels being 20-200 mg kg-1. Wastewater sludge from paper mills may contain bromine 20-100 mg kg-1 due the use of bromine based biocides. In other fuels bromine may be found in significant amounts in marine influenced coal deposits and peat as well as in biomass treated with brominated pesticides. In the experimental part SRF, spruce bark and wastewater sludge from a paper mill were co-fired in a full- scale bubbling fluidised bed (BFB) boiler, and the collected fuels, aerosols and waterwall deposits were analysed with the focus on the fate of bromine. Bromine was mainly found to form water soluble high vapour pressure alkali metal halides in the furnace - in the form of KBr(g) and NaBr(g) as

  10. Simultaneous balloon-borne measurements of the key inorganic bromine species BrO and BrONO2 in the stratosphere: DOAS and MIPAS-B evaluation

    Science.gov (United States)

    Kazarski, Sebastian; Maucher, Guido; Ebersoldt, Andreas; Butz, André; Friedl-Vallon, Felix; Höpfner, Michael; Kleinert, Anne; Nordmeyer, Hans; Oelhaf, Hermann; Pfeilsticker, Klaus; Sinnhuber, Björn-Martin; Wetzel, Gerald; Orphal, Johannes

    2015-04-01

    Inorganic bromine contributes to a loss of stratospheric ozone of about 25 - 30%. Past studies have demonstrated several uncertainties in the photochemistry of stratospheric bromine, especially by considering the three body reaction (kBrONO2) BrO + NO2 + M → BrONO2 + M, and the photolysis frequencies of BrONO2 (jBrONO2). Hence, an improved knowledge of the ratio jBrONO2/kBrONO2 is crucial to better assess the bromine-related loss of ozone as well as the total amount of bromine in the stratosphere. Here, we report on the first simultaneous balloon-borne measurements of NO2, BrO, and BrONO2 in the stratosphere, performed over Timmins (Ontario, 49 °N, Canada) on Sept., 7th and 8th, 2014. During the flight the targeted species were monitored by remote sensing in the UV, visible and mid-IR spectral ranges by Differential Optical Absorption Spectroscopy (DOAS) and Michelson Interferometer for Passive Atmospheric Sounding (MIPAS-B), respectively. The analysis and interpretation of the measurements involves radiative transfer as well as photochemical modelling. Major features of the applied techniques are reported and first results of the DOAS as well as MIPAS-B evaluation are discussed. Further investigations address inter-comparisons of the retrieved NO2, BrO, and O3 concentrations and volume mixing ratios, to demonstrate validations of both evaluation methods.

  11. 45 CFR 79.25 - Fees.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Fees. 79.25 Section 79.25 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROGRAM FRAUD CIVIL REMEDIES § 79.25 Fees. The party requesting a subpoena shall pay the cost of the fees and mileage of any witness subpoenaed in...

  12. 44 CFR 79.5 - Application process.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Application process. 79.5 Section 79.5 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... § 79.5 Application process. (a) Applicant or grantee. (1) States will be notified of the...

  13. 25 CFR 700.79 - Marriage.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Marriage. 700.79 Section 700.79 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Policies and Instructions Definitions § 700.79 Marriage. Marriage is a legally recorded marriage or a traditional...

  14. 14 CFR 141.79 - Flight training.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight training. 141.79 Section 141.79... OTHER CERTIFICATED AGENCIES PILOT SCHOOLS Operating Rules § 141.79 Flight training. (a) No person other... ratings and the minimum qualifications specified in the approved training course outline may give...

  15. 14 CFR 65.79 - Skill requirements.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Skill requirements. 65.79 Section 65.79... CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Mechanics § 65.79 Skill requirements. Each applicant for a... cover the applicant's basic skill in performing practical projects on the subjects covered by...

  16. 45 CFR 79.34 - Evidence.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Evidence. 79.34 Section 79.34 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROGRAM FRAUD CIVIL REMEDIES § 79.34 Evidence. (a) The ALJ shall determine the admissibility of evidence. (b) Except as provided in this part,...

  17. 49 CFR 79.9 - Design.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Design. 79.9 Section 79.9 Transportation Office of the Secretary of Transportation MEDALS OF HONOR § 79.9 Design. The Department is authorized to adopt and revise the existing designs for the award, rosette, and ribbon provided for by statute....

  18. Brominated flame retardants and organochlorine compounds in duplicate diet samples from a Portuguese academic community.

    Science.gov (United States)

    Coelho, Sónia D; Sousa, Ana C A; Isobe, Tomohiko; Kunisue, Tatsuya; Nogueira, António J A; Tanabe, Shinsuke

    2016-10-01

    Concentrations of persistent organic pollutants (POPs), including polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDDs), polychlorinated biphenyls (PCBs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), chlordane compounds (CHLs) and dichlorodiphenyltrichloroethane and its metabolites (DDTs), were measured in duplicate diet samples from 21 volunteers at a Portuguese academic community (University of Aveiro). Overall, the levels of the target compounds were low, with detection frequencies varying widely depending on the compounds and with brominated flame retardants (BFRs) registering the lowest detection frequencies. Among PCB congeners, nondioxin-like PCBs were predominant and detected in the majority of the samples. Organochlorine pesticides were also detected in the majority of the samples, with 100% detection for DDTs and HCHs. Estimated daily intakes (EDIs) were calculated using lower and upper bound estimations, and in both cases values were far below the currently established tolerable daily intakes for PCBs and OCs and the reference doses for PBDEs and HBCDDs. PMID:27367176

  19. Endocrine effects of some new brominated flame retardants

    Czech Academy of Sciences Publication Activity Database

    Ezechiáš, Martin; Svobodová, Kateřina; Cajthaml, Tomáš

    Praha : VŠCHT, 2012. s. 77-78. ISBN 978-80-7080-811-5. [Průmyslová ekologie /3./. 20.03.2012-23.03.2012, Hustopeče u Brna] R&D Projects: GA ČR GA104/09/0694 Institutional research plan: CEZ:AV0Z50200510 Keywords : Brominated flame retardants * Endocrine disruptors Subject RIV: EE - Microbiology, Virology

  20. Band structure of 79Br

    International Nuclear Information System (INIS)

    High-spin states of 79Br have been studied in the reaction 76Ge(7Li, 4nγ) at 32 MeV. A gamma-detector array with twelve Compton-suppressed HPGe detectors was used. The positive-parity yrast states, interpreted as a rotationally aligned g(9(2)) proton band, and the negative-parity ground state band have been extended to spins of (33(2+)) and (25(2-)), respectively. Lifetime measurements indicate that both bands have a similar quadrupole deformation of β2 ∼ 0.2. The positive-parity α = -(1(2)) band has been identified. Several new inter-band transitions are observed. A cranked-shell model analysis shows that the νg(9(2)) and πg(9(2)) alignments occur in the positive-parity and the negative-parity bands at rotational frequencies of ℎω ∼ 0.6 and 0.4 MeV, respectively. The level energies and the electromagnetic properties of the g(9(2)) band can be well reproduced by a particle-rotor model calculation with an axially symmetric core

  1. Measurement-based modeling of bromine chemistry in the boundary layer: 1. Bromine chemistry at the Dead Sea

    OpenAIRE

    Tas, E.; Peleg, M.; D. U. Pedersen; Matveev, V; Pour Biazar, A.; Luria, M.

    2006-01-01

    International audience The Dead Sea is an excellent natural laboratory for the investigation of Reactive Bromine Species (RBS) chemistry, due to the high RBS levels observed in this area, combined with anthropogenic air pollutants up to several ppb. The present study investigated the basic chemical mechanism of RBS at the Dead Sea using a numerical one-dimensional chemical model. Simulations were based on data obtained from comprehensive measurements performed at sites along the Dead Sea. ...

  2. High selectively oxidative bromination of toluene derivatives by the H2O2-HBr system

    Institute of Scientific and Technical Information of China (English)

    Jie Ju; Yu Jin Li; Jian Rong Gao; Jian Hong Jia; Liang Han; Wei Jian Sheng; Yi Xia Jia

    2011-01-01

    An aqueous solution of hydrogen peroxide and hydrogen bromide illuminated by a 60 W incandescent light bulb serves as a source of bromine radicals. Various substituted toluenes (NO2,Cl, Br, H, CH3) were high selectively brominated at the benzyl position for monobromination in CH2C12 at ice water with catalyst free. This simple but effective bromination of toluene derivatives with an aqueous H2O2-HBr system is characterized with the use of inexpensive reagents and a lower impact on the environment, which make it a good alternative to the existing bromination methods.

  3. Shuttle Environmental Assurance: Brominated Flame Retardants - Concerns, Drivers, Potential Impacts and Mitigation Strategies

    Science.gov (United States)

    Clark-Ingram, Marceia

    2010-01-01

    Brominated Flame Retardants (BFRs) are widely used in the manufacture of electrical and electronic components and as additives in formulations for foams, plastics and rubbers. The United States (US) and the European Union (EU)have increased regulation and monitoring of of targeted BFRs, such as Polybrominated Diphenyl Ethers (PBDEs) due to the bioaccumulative effects in humans and animals. In response, manufacturers and vendors of BFR-containing materials are changing flame-retardant additives, sometimes without notifying BFR users. In some instances, Deca-bromodiphenylether (Deca-BDE) and other families of flame retardants are being used as replacement flame retardants for penta-BDE and octa-BDE. The reformulation of the BFR-containing material typically results in the removal of the targeted PBDE and replacement with a non-PBDE chemical or non-targeted PBDE. Many users of PBDE -based materials are concerned that vendors will perform reformulation and not inform the end user. Materials performance such as flammability, adhesion , and tensile strength may be altered due to reformulation. The requalification of newly formulated materials may be required, or replacement materials may have to be identified and qualified. The Shuttle Enviornmental Assurance (SEA) team indentified a risk to the Space Shuttle Program associated with the possibility that targeted PBDEs may be replaced without notification. Resultant decreases in flame retardancy, Liquid Oxygen (LOX) compatibility, or material performance could have serious consequences.

  4. New insight into photo-bromination processes in saline surface waters: The case of salicylic acid

    International Nuclear Information System (INIS)

    It was shown, through a combination of field and laboratory observations, that salicylic acid can undergo photo-bromination reactions in sunlit saline surface waters. Laboratory-scale experiments revealed that the photochemical yields of 5-bromosalicylic acid and 3,5-dibromosalicylic acid from salicylic acid were always low (in the 4% range at most). However, this might be of concern since these compounds are potential inhibitors of the 20α-hydroxysteroid dehydrogenase enzyme, with potential implications in endocrine disruption processes. At least two mechanisms were involved simultaneously to account for the photo-generation of brominated substances. The first one might involve the formation of reactive brominated radical species (Br·, Br2·−) through hydroxyl radical mediated oxidation of bromide ions. These ions reacted more selectively than hydroxyl radicals with electron-rich organic pollutants such as salicylic acid. The second one might involve the formation of hypobromous acid, through a two electron oxidation of bromine ions by peroxynitrite. This reaction was catalyzed by nitrite, since these ions play a crucial role in the formation of nitric oxide upon photolysis. This nitric oxide further reacts with superoxide radical anions to yield peroxynitrite and by ammonium through the formation of N-bromoamines, probably due to the ability of N-bromoamines to promote the aromatic bromination of phenolic compounds. Field measurements revealed the presence of salicylic acid together with 5-bromosalicylic and 3,5-dibromosalicylic acid in a brackish coastal lagoon, thus confirming the environmental significance of the proposed photochemically induced bromination pathways. -- Highlights: ► Brominated derivatives of salicylic acid were detected in a brackish lagoon. ► A photochemical pathway was hypothesized to account for bromination of salicylic acid. ► Radical bromine species are partly responsible for the bromination process. ► Hypobromous acid might

  5. 44 CFR 79.9 - Grant administration.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Grant administration. 79.9... § 79.9 Grant administration. (a) The Grantee must follow FEMA grant requirements, including submission of performance and financial status reports, and shall follow adequate competitive...

  6. 7 CFR 1.79 - Credits.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Credits. 1.79 Section 1.79 Agriculture Office of the... Credits. On films on which the Department or one of its agencies provides special assistance it shall be mutually agreed by the producer and the Director of Information what credits shall be given to...

  7. 27 CFR 46.79 - Supervision.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Supervision. 46.79 Section... § 46.79 Supervision. Before payment is made under this subpart in respect of the tax, or tax and duty... under the supervision of an appropriate TTB officer who will be assigned for that purpose by...

  8. 44 CFR 79.3 - Responsibilities.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Responsibilities. 79.3... § 79.3 Responsibilities. (a) Federal Emergency Management Agency (FEMA). Administer and provide... responsibilities of the “State” as the term is used in this part, as applicant or grantee, described in...

  9. 40 CFR 79.66 - Neuropathology assessment.

    Science.gov (United States)

    2010-07-01

    ... fixed in fixative for at least 48 hours prior to further tissue processing. (B) Dehydration. All tissue... evaluation. In addition to information meeting the requirements stated under 40 CFR 79.60 and 79.61, the... information on this test guideline, the following references should be consulted. (1) 40 CFR...

  10. 32 CFR 552.79 - Suspension action.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Suspension action. 552.79 Section 552.79 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL... Suspension action. (a) When suspended for cause, immediately notify the company and the agent, in writing,...

  11. 40 CFR 79.54 - Tier 3.

    Science.gov (United States)

    2010-07-01

    ... testing may be indicated if the results of the In vivo Micronucleus Assay, required under § 79.64, the In... FUELS AND FUEL ADDITIVES Testing Requirements for Registration § 79.54 Tier 3. (a) General Criteria for Requiring Tier 3 Testing. (1) Tier 3 testing shall be required of a manufacturer or group of...

  12. Bayesian statistical modeling of disinfection byproduct (DBP) bromine incorporation in the ICR database.

    Science.gov (United States)

    Francis, Royce A; Vanbriesen, Jeanne M; Small, Mitchell J

    2010-02-15

    Statistical models are developed for bromine incorporation in the trihalomethane (THM), trihaloacetic acids (THAA), dihaloacetic acid (DHAA), and dihaloacetonitrile (DHAN) subclasses of disinfection byproducts (DBPs) using distribution system samples from plants applying only free chlorine as a primary or residual disinfectant in the Information Collection Rule (ICR) database. The objective of this study is to characterize the effect of water quality conditions before, during, and post-treatment on distribution system bromine incorporation into DBP mixtures. Bayesian Markov Chain Monte Carlo (MCMC) methods are used to model individual DBP concentrations and estimate the coefficients of the linear models used to predict the bromine incorporation fraction for distribution system DBP mixtures in each of the four priority DBP classes. The bromine incorporation models achieve good agreement with the data. The most important predictors of bromine incorporation fraction across DBP classes are alkalinity, specific UV absorption (SUVA), and the bromide to total organic carbon ratio (Br:TOC) at the first point of chlorine addition. Free chlorine residual in the distribution system, distribution system residence time, distribution system pH, turbidity, and temperature only slightly influence bromine incorporation. The bromide to applied chlorine (Br:Cl) ratio is not a significant predictor of the bromine incorporation fraction (BIF) in any of the four classes studied. These results indicate that removal of natural organic matter and the location of chlorine addition are important treatment decisions that have substantial implications for bromine incorporation into disinfection byproduct in drinking waters. PMID:20095529

  13. The Evolution of a Green Chemistry Laboratory Experiment: Greener Brominations of Stilbene

    Science.gov (United States)

    McKenzie, Lallie C.; Huffman, Lauren M.; Hutchison, James E.

    2005-01-01

    The use of green metrics to compare three bromination laboratory procedures demonstrates the effectiveness of an incremental greening process for chemistry curricula. Due to this process, the bromination of alkenes can be introduced to students through the use of a safe, effective, modern practice.

  14. 40 CFR 721.775 - Brominated aromatic com-pound (generic name).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Brominated aromatic com-pound (generic name). 721.775 Section 721.775 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.775 Brominated aromatic com-pound (generic name). (a)...

  15. Biosynthesis of brominated tyrosine metabolites by Aplysina fistularis.

    Science.gov (United States)

    Carney, J R; Rinehart, K L

    1995-07-01

    The biosynthesis of brominated tyrosine metabolites by the marine sponge Aplysina fistularis was investigated. [U-14C]-L-Tyrosine, [U-14C]-L-3-bromotyrosine, and [U-14C]-L-3,5-dibromotyrosine were incorporated into both dibromoverongiaquinol [1] and aeroplysinin-1 [2], and [methyl-14C]methionine was specifically incorporated into the O-methyl group group of 2. [Methyl-14C]-L-O-methyltyrosine, [methyl-14C]-L-3,5-dibromo-O-methyltyrosine, and several putative nitrile precursors were not incorporated into 1 or 2. PMID:7561906

  16. Future chlorine-bromine loading and ozone depletion

    Science.gov (United States)

    Prather, Michael J.; Ibrahim, Abdel Moneim; Sasaki, Toru; Stordal, Frode; Visconti, Guido

    1991-01-01

    The prediction of future ozone requires three elements: (1) a scenario for the net emissions of chemically and radiatively active trace gases from the land and oceans; (2) a global atmospheric model that projects the accumulation of these gases; and (3) a chemical transport model that describes the distribution of ozone for a prescribed atmospheric composition and climate. This chapter, of necessity, presents models for all three elements and focuses on the following: (1) atmospheric abundance of chlorine and bromine in the form of halocarbons; and (2) the associated perturbations to stratospheric ozone.

  17. Research on the phenomenon of graphitization. Crystallographic study - Study of bromine sorption

    International Nuclear Information System (INIS)

    This research thesis reports the study of the mechanism of graphitization of carbon by using X-ray diffraction analysis and the physical and chemical study of lamellar reactions between carbon and bromine. The author first presents generalities and results of preliminary studies (meaning of graphitization, presentation of the various carbon groups and classes), and then reports the study of the graphitization of compact carbons (soft carbons). More precisely, he reports the crystallographic study of partially graphitized carbons: methods and principles, experimental results and their analysis, discussion of the graphitization mechanism. In the next part, the author reports the study of bromine sorption on carbons: experimental method, isotherms of a natural graphite and of a graphitized carbon, structure of carbon-bromine complexes, isotherms of graphitizable carbons and of all other carbons, distribution of bromine layers in partially graphitized carbons, bromine sorption and Fermi level

  18. Labeling of receptor ligands with bromine radionuclides. Progress report, March 1, 1981-February 28, 1982

    International Nuclear Information System (INIS)

    In recent years there has been an interest in the use of various radioisotopes of bromine as labels for radiopharmaceuticals. Although radioisotopes of iodine have been used extensively as radiopharmaceutical labels, there are several advantages associated with the use of radiobromine as a label, due primarily to increased stability of bonds to the radiohalide and smaller steric perturbation resulting from substitution of the radiohalide. Methods of attaching radiobromine to receptor ligands with the potential of mapping estrogen receptors in mammary tumors and uteri were studied. Two ligands were studied extensively in vitro and in animal models; preliminary studies were also carried out in humans. To date, the only radioisotope of bromine used was bromine-77. In addition, a series of model compounds were labeled with bromine-77 using a recently described method for rapid bromination; the scope and limitations of this new rapid radiobromination technique were evaluated

  19. Algae form brominated organic compounds in surface waters

    Energy Technology Data Exchange (ETDEWEB)

    Huetteroth, A.; Putschew, A.; Jekel, M. [Tech. Univ. Berlin (Germany)

    2004-09-15

    Monitoring of organic halogen compounds, measured as adsorbable organic bromine (AOBr) revealed seasonal high concentrations of organic bromine compounds in a surface water (Lake Tegel, Berlin, Germany). Usually, in late summer, concentrations are up to five times higher than during the rest of the year. The AOBr of the lake inflows (throughout the year less then 6 {mu}g/L) were always lower then those in the lake, which indicates a production of AOBr in the lake. A correlation of the AOBr and chlorophyll-a concentration (1) in the lake provides first evidence for the influence of phototrophic organisms. The knowledge of the natural production of organohalogens is relatively recent. Up to now there are more then 3800 identified natural organohalogen compounds that have been detected in marine plants, animals, and bacteria and also in terrestrial plants, fungi, lichen, bacteria, insects, some higher animals, and humans. Halogenated organic compounds are commonly considered to be of anthropogenic origin; derived from e.g. pharmaceuticals, herbicides, fungicides, insecticides, flame retardants, intermediates in organic synthesis and solvents. Additionally they are also produced as by-products during industrial processes and by waste water and drinking water disinfection. Organohalogen compounds may be toxic, persistent and/or carcinogenic. In order to understand the source and environmental relevance of naturally produced organobromine compounds in surface waters, the mechanism of the formation was investigated using batch tests with lake water and algae cultures.

  20. Comparative environmental analysis of waste brominated plastic thermal treatments

    International Nuclear Information System (INIS)

    The aim of this research activity is to investigate the environmental impact of different thermal treatments of waste electric and electronic equipment (WEEE), applying a life cycle assessment methodology. Two scenarios were assessed, which both allow the recovery of bromine: (A) the co-combustion of WEEE and green waste in a municipal solid waste combustion plant, and (B) the staged-gasification of WEEE and combustion of produced syngas in gas turbines. Mass and energy balances on the two scenarios were set and the analysis of the life cycle inventory and the life cycle impact assessment were conducted. Two impact assessment methods (Ecoindicator 99 and Impact 2002+) were slightly modified and then used with both scenarios. The results showed that scenario B (staged-gasification) had a potentially smaller environmental impact than scenario A (co-combustion). In particular, the thermal treatment of staged-gasification was more energy efficient than co-combustion, and therefore scenario B performed better than scenario A, mainly in the impact categories of 'fossil fuels' and 'climate change'. Moreover, the results showed that scenario B allows a higher recovery of bromine than scenario A; however, Br recovery leads to environmental benefits for both the scenarios. Finally the study demonstrates that WEEE thermal treatment for energy and matter recovery is an eco-efficient way to dispose of this kind of waste

  1. Pulse radiolysis studies of the reactions of bromine atoms and dimethyl sulfoxide-bromine atom complexes with alcohols

    International Nuclear Information System (INIS)

    Dimethylsulfoxide (DMSO)-Br complexes were generated by pulse radiolysis of DMSO/bromomethane mixtures and the formation mechanism and spectral characteristics of the formed complexes were investigated in detail. The rate constant for the reaction of bromine atoms with DMSO and the extinction coefficient of the complex were obtained to be 4.6x109 M-1 s-1 and 6300 M-1 cm-1 at the absorption maximum of 430 nm. Rate constants for the reaction of bromine atoms with a series of alcohols were determined in CBrCl3 solutions applying a competitive kinetic method using the DMSO-Br complex as the reference system. The obtained rate constants were ∼108 M-1 s-1, one or two orders larger than those reported for highly polar solvents. Rate constants of DMSO-Br complexes with alcohols were determined to be ∼ 107 M-1 s-1. A comparison of the reactivities of Br atoms and DMSO-Br complexes with those of chlorine atoms and chlorine atom complexes which are ascribed to hydrogen abstracting reactants strongly indicates that hydrogen abstraction from alcohols is not the rate determining step in the case of Br atoms and DMSO-Br complexes

  2. Effects of bromination on the viscoelastic response of vinyl ester nanocomposites

    Directory of Open Access Journals (Sweden)

    2009-11-01

    Full Text Available Fire, smoke and toxicity are of significant concern for composite materials used in marine applications. Bromination of vinyl ester resin imparts fire retardancy as manifested by a reduction in the amount of smoke, carbon monoxide, and corrosive combustion products. In this research, the viscoelastic properties, modulus (stiffness and damping (energy dissipation, of 1.25 and 2.5 wt. percent nanoclay and exfoliated graphite nanoplatelet (xGnP reinforced non-brominated and brominated vinyl ester have been studied over a range of temperature and frequency. Effects of frequency on the viscoelastic behavior were investigated using a Dynamic Mechanical Analyzer (DMA by sweeping the frequency over three decades: 0.01, 0.1, 1 and 10 Hz, and temperature range from 30–150°C at a step rate of 4°C per minute. Master curves were generated by time-temperature superposing the experimental data at a reference temperature. The nano reinforced composites showed a drop in initial storage modulus with bromination. Nanocomposites with 1.25 and 2.5 wt. percent graphite had the highest storage modulus among brominated specimens. Bromination was also found to significantly increase the glass transition temperature (Tg and damping for all nanocomposites. Among the brominated specimens, 1.25 wt. Percent graphite platelet reinforced vinyl ester exhibited the best viscoelastic response with high damping and glass transition temperature, along with superior storage modulus over a longer time period.

  3. The contribution of anthropogenic bromine emissions to past stratospheric ozone trends: a modelling study

    Directory of Open Access Journals (Sweden)

    B.-M. Sinnhuber

    2009-04-01

    Full Text Available Bromine compounds play an important role in the depletion of stratospheric ozone. We have calculated the changes in stratospheric ozone in response to changes in the halogen loading over the past decades, using a two-dimensional (latitude/height model constrained by source gas mixing ratios at the surface. Model calculations of the decrease of total column ozone since 1980 agree reasonably well with observed ozone trends, in particular when the contribution from very short-lived bromine compounds is included. Model calculations with bromine source gas mixing ratios fixed at 1959 levels, corresponding approximately to a situation with no anthropogenic bromine emissions, show an ozone column reduction between 1980 and 2005 at Northern Hemisphere mid-latitudes of only ≈55% compared to a model run including all halogen source gases. In this sense anthropogenic bromine emissions are responsible for ≈45% of the model estimated column ozone loss at Northern Hemisphere mid-latitudes. However, since a large fraction of the bromine induced ozone loss is due to the combined BrO/ClO catalytic cycle, the effect of bromine would have been smaller in the absence of anthropogenic chlorine emissions. The chemical efficiency of bromine relative to chlorine for global total ozone depletion from our model calculations, expressed by the so called α-factor, is 64 on an annual average. This value is much higher than previously published results. Updates in reaction rate constants can explain only part of the differences in α. The inclusion of bromine from very short-lived source gases has only a minor effect on the global mean α-factor.

  4. Fate and metabolism of the brominated flame retardant tetrabromobisphenol A (TBBPA) in rice cell suspension culture.

    Science.gov (United States)

    Wang, Songfeng; Cao, Siqi; Wang, Yongfeng; Jiang, Bingqi; Wang, Lianhong; Sun, Feifei; Ji, Rong

    2016-07-01

    Tetrabromobisphenol A (TBBPA) is the brominated flame retardant with the highest production volume and its bioaccumulation in environment has caused both human health and environmental concerns, however the fate and metabolism of TBBPA in plants is unknown. We studied the fate, metabolites, and transformation of (14)C-labeled TBBPA in rice cell suspension culture. During the incubation for 14 days, TBBPA degradation occurred continuously in the culture, accompanied by formation of one anisolic metabolite [2,6-dibromo-4-(2-(2-hydroxy)-propyl)-anisole] (DBHPA) (50% of the degraded TBBPA) and cellular debris-bound residues (46.4%) as well as mineralization (3.6%). The cells continuously accumulated TBBPA in the cytoplasm, while a small amount of DBHPA (2.1% of the initially applied TBBPA) was detectable inside the cells only at the end of incubation. The majority of the accumulated residues in the cells was attributed to the cellular debris-bound residues, accounting for 70-79% of the accumulation after the first incubation day. About 5.4% of the accumulation was associated with cell organelles, which contributed 7.5% to the cellular debris-bound residues. Based on the fate and metabolism of TBBPA in the rice cell suspension culture, a type II ipso-substitution pathway was proposed to describe the initial step for TBBPA degradation in the culture and balance the fate of TBBPA in the cells. To the best of our knowledge, our study provides for the first time the insights into the fate and metabolism of TBBPA in plants and points out the potential role of type II ipso-hydroxylation substitution in degradation of alkylphenols in plants. Further studies are required to reveal the mechanisms for the bound-residue formation (e.g., binding of residues to specific cell wall components), nature of the binding, and toxicological effects of the bound residues and DBHPA. PMID:27105166

  5. 溴化蓖麻油多元醇合成及其制备的阻燃聚氨酯硬泡性能%The Synthesis of Bromine-containing Castor Oil Polyol and the Flame-retardant Polyurethane Foam Prooerties

    Institute of Scientific and Technical Information of China (English)

    何明; 罗振扬; 史以俊; 顾晓利; 张银萍

    2011-01-01

    A novel bromine-containing castor oil based polyol was prepared via the reaction of glycerin-exchanged castor oil and bromine.Structure of bromation product was analyzed by FT-IR.The basic characters of the polyol, such as viscosity, hydroxyl value and acid value were investigated.The effects of bromine-containing castor oil based polyols on properties of the rigid polyurethane foams, especially on their resistance to combustion, were studied by foam experiment, oxygen index, smoke density and horizontal burning experiments.It was compared with the foam prepared by RB-79 of Albemarle Corporation.It was found that the bromine-containing castor oil based polyols were effective for improving the resistance to combustion of rigid polyurethane foams, having the same effects with the commercial flame retardant RB-79 of Albemarle Corporation.%采用可再生的醇解蓖麻油多元醇为原料,与液溴进行加成反应制备溴化蓖麻油多元醇,通过红外光谱证实发生了溴化反应,并测定了产物粘度、羟值、酸值.通过发泡实验和氧指数、烟密度、水平燃烧等测试手段,考察了溴化蓖麻油基聚氨酯硬泡发泡参数和阻燃性质,并与工业级阻燃荆雅保RB-79制备的聚氨酯硬泡进行比较.结果表明,由溴化蓖麻油多元醇制备的泡沫体现出较好阻燃性能,与RB-79的阻燃效果相当.

  6. Enhancement of the carbon electrode capacitance by brominated hydroquinones

    Science.gov (United States)

    Gastol, Dominika; Walkowiak, Jedrzej; Fic, Krzysztof; Frackowiak, Elzbieta

    2016-09-01

    This paper presents supercapacitors utilizing new redox-active electrolytes with bromine species. Two sources of Br specimen were investigated, i.e. dibromodihydroxybenzene dissolved in KOH and potassium bromide dissolved in KOH with hydroxybenzene additive. KOH-activated carbon, exhibiting a well-developed porosity, was incorporated as an electrode material. The tested systems revealed a capacitance enhancement explained by Br- and partial BrO3- redox activity. The optimisation of the electrolyte concentration resulted in a capacitance value of 314 F g-1 achieved at 1.1 V voltage range. Good cyclability performance (11% capacitance loss) combined with a high capacitance value (244 F g-1) were obtained for the system operating in 0.2 mol L- 1 C6H4Br2O2 in 2 mol L-1 KOH electrolytic solution.

  7. Preparation and evaluation of composite membranes for zinc/bromine storage batteries

    Science.gov (United States)

    Arnold, Charles, Jr.; Assink, Roger A.

    Low coulombic efficiencies of zinc/bromine redox batteries were attributed to migration of bromine and negatively charged bromine moieties through the microporous separator used to separate the catholyte from the anolyte. While it was demonstrated that improvements in coulombic efficiency can be achieved by replacing the microporous separator with a cationic ion exchange membrane, these membranes are expensive and/or not sufficiently conductive to be practicable. It was found that the rate of bromine permeation can be reduced by two orders of magnitude with minimal decreases in conductivity by impregnating commercial microporous polyethylene type separators with sulfonated polysulfone, a cationic polyelectrolyte that was developed in earlier work for other redox storage batteries.

  8. A Novel Protocol for the Regioselective Bromination of Primary Alcohols in Unprotected Carbohydrates or Glycosides

    Institute of Scientific and Technical Information of China (English)

    薛伟华; 张立芬

    2012-01-01

    The regioselective and efficient bromination of primary hydroxyl groups in unprotected carbohydrates or glycosides is successfully achieved by using (chloro-phenylthio-methylene)dimethylammoniumchloride (CPMA) in the presence of tetrabutylammonium bromide (TBAB) in dry DMF.

  9. Evaluation of carbon cryogels used as cathodes for non-flowing zinc-bromine storage cells

    Energy Technology Data Exchange (ETDEWEB)

    Ayme-Perrot, David; Walter, Serge; Gabelica, Zelimir [Groupe Securite et Ecologie Chimiques (GSEC), ENSCMu, 3 rue Alfred Werner, F-68093 Mulhouse Cedex (France); Valange, Sabine [Laboratoire de Catalyse en Chimie Organique (LACCO), ESIP, 40 Avenue du Recteur Pineau, F-86022 Poitiers Cedex (France)

    2008-01-03

    Monolithic megaloporous carbon cryogels were examined for their potential applications as cathodic electrodes in secondary zinc-bromine cells. This work investigates the possibility of using their particular macroporous texture as microscopic bromine tanks in a zinc/bromine battery. The electrochemical behaviour of a cell based upon such a Br{sub 2} electrode was studied and discussed in terms of energy yields, energy storage capability and cycle life. Good storages (over 20 Wh kg{sup -1}) could be obtained during the first 2 h of cell charging for currents between 10 and 20 mA g{sup -1}. The energy yield remains almost constant during a fairly large number of cycles, basically for weak charges (e.g. 25 C g{sup -1}). Our findings show that the good cyclability of the cathodic electrode is a consequence of the liquid state of the active bromine phase. (author)

  10. Dynamic dielectric properties and the γ transition of bromine doped polyacrylonitrile

    Directory of Open Access Journals (Sweden)

    2007-10-01

    Full Text Available Based on monitoring the γ process (the lowest temperature-relaxation in polyacrylonitrile (PAN by dynamic dielectric spectroscopy, new evidence for the formation of a charge transfer complex between bromine dopants and nitrile groups is presented. The experimental work is carried out on PAN and nitrile polymerized PAN with and without bromine doping and the effects of these factors on the γ process are measured. Nitrile polymerization results in diminishing of the γ process and in a 15% increase in its activation energy, whereas bromine doping produces splitting of the original γ process in PAN – coupled with a significant activation energy increase – and its complete disappearance in nitrile polymerized PAN. Both the splitting of the γ process and the higher activation energy reflect bromine-nitrile adduct formation..

  11. Strand breaks in plasmid DNA, natural and brominated, by low-energy X-rays

    International Nuclear Information System (INIS)

    Single- and double-strand breaks were measured in Col E1 plasmid DNA, natural and partially brominated, irradiated with monoenergetic X-rays (from a synchrotron radiation source) on both sides of the K-absorption edge for Br. The fraction of the undamaged supercoiled form decreased exponentially with the photon dose; its yield in the brominated DNA did not exhibit any energy-dependence. This result is consistent with the calculated relative contributions of photoelectric interactions with individual component atoms which show that an electron flux originating in light atoms outweighs that from bromine. However, X-rays of energy above the Br K-edge appear slightly more efficient in producing double-strand breaks. This result seems to suggest that the positive charge and submolecular effects associated with the photo-absorption in bromine play some role in damaging processes, besides the initial distribution of deposited electron energy. (author)

  12. Bromine determination by neutron activation analysis and its distribution in the atmosphere

    International Nuclear Information System (INIS)

    Bromine, one of the main participants in ozone layer destruction, is 10 to 100 times more effective than chlorine. There are two principal sources of methyl bromide emissions: the oceans and some pesticides that are used in farming. Bromine was detected in 'premium' and 'magna sin' gasolines (2.86±0.96 and 1.54±0.38 ppm, respectively) as well as in condensed water found in exhaust pipes of vehicles. In addition, samples of rainwater were also analyzed to determine atmospheric bromine concentration. In water samples Br concentrations ranging from 2.09 to 0.06 ppm were found. The techniques utilised were neutron activation analysis and high voltage electrophoresis, the latter to determine the chemical form of bromine in condensed water samples. Finally, suspended particles from rainwater were also analysed by scanning electron microscopy (SEM). (author)

  13. New insight into photo-bromination processes in saline surface waters: The case of salicylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Tamtam, Fatima; Chiron, Serge, E-mail: serge.chiron@msem.univ-montp2.fr

    2012-10-01

    It was shown, through a combination of field and laboratory observations, that salicylic acid can undergo photo-bromination reactions in sunlit saline surface waters. Laboratory-scale experiments revealed that the photochemical yields of 5-bromosalicylic acid and 3,5-dibromosalicylic acid from salicylic acid were always low (in the 4% range at most). However, this might be of concern since these compounds are potential inhibitors of the 20{alpha}-hydroxysteroid dehydrogenase enzyme, with potential implications in endocrine disruption processes. At least two mechanisms were involved simultaneously to account for the photo-generation of brominated substances. The first one might involve the formation of reactive brominated radical species (Br{center_dot}, Br{sub 2}{center_dot}{sup -}) through hydroxyl radical mediated oxidation of bromide ions. These ions reacted more selectively than hydroxyl radicals with electron-rich organic pollutants such as salicylic acid. The second one might involve the formation of hypobromous acid, through a two electron oxidation of bromine ions by peroxynitrite. This reaction was catalyzed by nitrite, since these ions play a crucial role in the formation of nitric oxide upon photolysis. This nitric oxide further reacts with superoxide radical anions to yield peroxynitrite and by ammonium through the formation of N-bromoamines, probably due to the ability of N-bromoamines to promote the aromatic bromination of phenolic compounds. Field measurements revealed the presence of salicylic acid together with 5-bromosalicylic and 3,5-dibromosalicylic acid in a brackish coastal lagoon, thus confirming the environmental significance of the proposed photochemically induced bromination pathways. -- Highlights: Black-Right-Pointing-Pointer Brominated derivatives of salicylic acid were detected in a brackish lagoon. Black-Right-Pointing-Pointer A photochemical pathway was hypothesized to account for bromination of salicylic acid. Black

  14. Bromine as a Potential Threat to the Aquatic Environment in Areas of Mining Operations

    OpenAIRE

    Winid Bogumiła

    2013-01-01

    Fresh water normally contains limited quantities of bromine. The average content of bromine in the surface and groundwater active exchange zone generally does not exceed 200 μg/dm3 (0.2 mg/dm3). Mineralized waters, including some specific therapeutic waters, thermal waters, and brines, may contain bromides in amounts greater than in ordinary groundwater. Bromides will penetrate into groundwater and surface water due to salty groundwater inflow. In areas of mining operations, the management of...

  15. Complete Reductive Dehalogenation of Brominated Biphenyls by Anaerobic Microorganisms in Sediment

    OpenAIRE

    Bedard, Donna L.; Van Dort, Heidi M.

    1998-01-01

    We sought to determine whether microorganisms from the polychlorinated biphenyl (PCB)-contaminated sediment in Woods Pond (Lenox, Mass.) could dehalogenate brominated biphenyls. The PCB dechlorination specificities for the microorganisms in this sediment have been well characterized. This allowed us to compare the dehalogenation specificities for brominated biphenyls and chlorinated biphenyls within a single sediment. Anaerobic sediment microcosms were incubated separately at 25°C with 16 dif...

  16. Characterization and cyclic performance of membranes in hydrogen-bromine battery

    OpenAIRE

    Hugo, Yohanes

    2015-01-01

    A large renewable energy integration needs to be coupled with a low cost energy storage technology. One of the promising energy storage alternatives for the commercial market segment is the hydrogen bromine flow battery. Although the technology has been explored since 1980, the development of the hydrogen bromine flow battery system is still in the research phase due to the system complexity, the safety aspect, and technical problems. The literature review revealed that costs of the system an...

  17. Performance and Degradation of A Lithium-Bromine Rechargeable Fuel Cell Using Highly Concentrated Catholytes

    OpenAIRE

    Bai, Peng; Bazant, Martin Z.

    2016-01-01

    Lithium-air batteries have been considered as ultimate solutions for the power source of long-range electrified transportation, but state-of-the-art prototypes still suffer from short cycle life, low efficiency and poor power output. Here, a lithium-bromine rechargeable fuel cell using highly concentrated bromine catholytes is demonstrated with comparable specific energy, improved power density, and higher efficiency. The cell is similar in structure to a hybrid-electrolyte Li-air battery, wh...

  18. Bromine atom production and chain propagation during springtime Arctic ozone depletion events in Barrow, Alaska

    OpenAIRE

    Thompson, Chelsea R.; Shepson, Paul B.; Liao, Jin; Huey, L. Greg; Cantrell, Chris; Flocke, Frank; Orlando, John

    2016-01-01

    Ozone depletion events (ODEs) in the Arctic are primarily controlled by a bromine radical-catalyzed destruction mechanism that depends on the efficient production and recycling of Br atoms. Numerous laboratory and modeling studies have suggested the importance of heterogeneous recycling of Br through HOBr reaction with bromide on saline surfaces. However, the gas-phase regeneration of bromine atoms through BrO-BrO radical reactions has been assumed to be an efficient, if not dominant, pa...

  19. Gaia Paradigm: A Biotic Origin Of The Polar Sunrise Arctic Bromine Explosion

    OpenAIRE

    Iudin, M.

    2008-01-01

    The main attention is given to discussion of the natural causes and regularities of the Arctic bromine pollution. We make notice of marine microbial organisms and their metabolism as a prime driving force for the elemental biogeochemical cycles. One of the important conclusions of this study is on similarity between ocean bromine concentrating as by-product of the marine microbial activities and nitrogen fixation by soil bacteria. In both cases, microbial organisms and their food webs maintai...

  20. Springtime surface ozone fluctuations at high Arctic latitudes and their possible relationship to atmospheric bromine

    Science.gov (United States)

    Oltmans, Samuel J.; Sheridan, Patrick J.; Schnell, Russell C.; Winchester, John W.

    1988-01-01

    At high Arctic stations such as Barrow, Alaska, springtime near-surface ozone amounts fluctuate between the highest and lowest values seen during the course of the year. Episodes when the surface ozone concentration is essentially zero last up to several days during this time of year. In the Arctic Gas and Aerosol Sampling Program (AGASP-I and AGASP-II) in 1983 and 1986, it was found that ozone concentrations often showed a very steep gradient in altitude with very low values near the surface. The cold temperatures, and snow-covered ground make it unlikely that the surface itself would rapidly destroy significant amounts of ozone. The AGASP aircraft measurements that found low ozone concentrations in the lowest layers of the troposphere also found that filterable excess bromine (the amount of bromine in excess of the sea salt component) in samples collected wholly or partially beneath the temperature inversion had higher bromine concentrations than other tropospheric samples. Of the four lowest ozone minimum concentrations, three of them were associated with the highest bromine enrichments. Surface measurements of excess filterable bromine at Barrow show a strong seasonal dependence with values rising dramatically early in March, then declining in May. The concentration of organic bromine gases such as bromoform rise sharply during the winter and then begin to decline after March with winter and early spring values at least three times greater than the summer minimum.

  1. Photothermally induced bromination of carbon/polymer bipolar plate materials for fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Schade, Martin; Franzka, Steffen [Fakultät für Chemie, Universität Duisburg-Essen, 45117 Essen (Germany); Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Carl-Benz-Straße 199, 47057 Duisburg (Germany); Cappuccio, Franco; Peinecke, Volker; Heinzel, Angelika [Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Carl-Benz-Straße 199, 47057 Duisburg (Germany); Zentrum für BrennstoffzellenTechnik (ZBT), Carl-Benz-Straße 201, 47057 Duisburg (Germany); Hartmann, Nils, E-mail: nils.hartmann@uni-due.de [Fakultät für Chemie, Universität Duisburg-Essen, 45117 Essen (Germany); Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Carl-Benz-Straße 199, 47057 Duisburg (Germany)

    2015-05-01

    Graphical abstract: - Highlights: • Photothermal laser bromination of carbon/polymer materials is demonstrated. • Using a microfocused laser functionalized domains with diameters of 5 μm and 100 μm and more can be fabricated. • Bromine groups can be transformed in a variety of other chemical functionalities, i.e. amine groups. • Depending on the chemical functionality, the local chemical affinity and wettability is changed. • The routine can be applied to standard bipolar plate materials used for fuel cell applications. - Abstract: A facile photothermal procedure for direct functionalization of carbon/polymer bipolar plate materials is demonstrated. Through irradiation with a microfocused beam of an Ar{sup +}-laser at λ = 514 nm in gaseous bromine and distinct laser powers and pulse lengths local bromination of the carbon/polymer material takes place. At a 1/e spot diameter of 2.1 μm, functionalized surface areas with diameters down to 5 μm are fabricated. In complementary experiments large-area bromination is investigated using an ordinary tungsten lamp. For characterization contact angle goniometry, X-ray photoelectron spectroscopy and electron microscopy in conjunction with labeling techniques are employed. After irradiation bromine groups can easily be substituted by other chemical functionalities, e.g. azide and amine groups. This provides a facile approach in order to fabricate surface patterns and gradient structures with varying wetting characteristics. Mechanistic aspects and prospects of photothermal routines in micropatterning of carbon/polymer materials are discussed.

  2. Photothermally induced bromination of carbon/polymer bipolar plate materials for fuel cell applications

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Photothermal laser bromination of carbon/polymer materials is demonstrated. • Using a microfocused laser functionalized domains with diameters of 5 μm and 100 μm and more can be fabricated. • Bromine groups can be transformed in a variety of other chemical functionalities, i.e. amine groups. • Depending on the chemical functionality, the local chemical affinity and wettability is changed. • The routine can be applied to standard bipolar plate materials used for fuel cell applications. - Abstract: A facile photothermal procedure for direct functionalization of carbon/polymer bipolar plate materials is demonstrated. Through irradiation with a microfocused beam of an Ar+-laser at λ = 514 nm in gaseous bromine and distinct laser powers and pulse lengths local bromination of the carbon/polymer material takes place. At a 1/e spot diameter of 2.1 μm, functionalized surface areas with diameters down to 5 μm are fabricated. In complementary experiments large-area bromination is investigated using an ordinary tungsten lamp. For characterization contact angle goniometry, X-ray photoelectron spectroscopy and electron microscopy in conjunction with labeling techniques are employed. After irradiation bromine groups can easily be substituted by other chemical functionalities, e.g. azide and amine groups. This provides a facile approach in order to fabricate surface patterns and gradient structures with varying wetting characteristics. Mechanistic aspects and prospects of photothermal routines in micropatterning of carbon/polymer materials are discussed

  3. 79 new cyclopeptides discovered from 28 plants

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ A key innovative research result has been achieved in systematic chemistry of plant cyclopeptides (PCPs), a group of important plant metabolites, by a research team with the CAS Kunming Institute of Botany (KIB)in the capital of southwest China's Yunnan Province. According to a recent announcement released by the Institute, its chemists have brought to light 79 new PCPs.

  4. 40 CFR 79.59 - Reporting requirements.

    Science.gov (United States)

    2010-07-01

    ... applicability of the special provisions for aerosol products, pursuant to § 79.58(e), then the purpose and... governed by the provisions of 40 CFR part 2. .... (a) Timing. (1) The manufacturer of each designated fuel or fuel additive shall submit to EPA...

  5. Hariduskulud kasvavad 7,9% / Lauri Luik

    Index Scriptorium Estoniae

    Luik, Lauri, 1982-

    2011-01-01

    Õpetajate palga tõstmisest. 2011. aasta riigieelarves on hariduskulude tõus 7,9 protsenti. Vastukaja Kalle Kalda avalikule kirjale: Lauri Luik, valet vähemaks enne valimisi! Õpetajate Leht 2010 8. okt. lk. 2

  6. 28 CFR 79.11 - Definitions.

    Science.gov (United States)

    2010-07-01

    ...) The Nevada Test Site (NTS), Nevada; (2) The Pacific Test Sites (Bikini Atoll, Enewetak Atoll, Johnston... for the purpose of monitoring fallout from an atmospheric nuclear test conducted at the Nevada Test... test conducted by the United States prior to January 1, 1963, as listed in § 79.31(d). (c)...

  7. 40 CFR 86.337-79 - Information.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Information. 86.337-79 Section 86.337... Information. The following information, as applicable, shall be recorded for each test: (a) Engine description and specification. A copy of the information specified in this paragraph must accompany each...

  8. Utilization of a Green Brominating Agent for the Spectrophotometric Determination of Pipazethate HCl in Pure Form and Pharmaceutical Preparations

    OpenAIRE

    Ayman A. Gouda

    2013-01-01

    Five simple, accurate, and sensitive spectrophotometric methods (A–E) have been described for the indirect assay of pipazethate HCl (PZT) either in pure form or in pharmaceutical preparations. The proposed methods are based on the bromination of pipazethate HCl with a solution of excess bromate-bromide mixture in hydrochloric acid medium and subsequent estimation of the residual bromine by different reaction schemes. In the first three methods (A–C), the determination of the residual bromine ...

  9. Occurrences and inventories of heavy metals and brominated flame retardants in wastes from printed circuit board production.

    Science.gov (United States)

    Zhou, Xiaoyu; Guo, Jie; Zhang, Wei; Zhou, Peng; Deng, Jingjing; Lin, Kuangfei

    2014-09-01

    Pollutants including heavy metals and brominated flame retardant were detected in 10 types of production wastes from a typical printed circuit board manufacturing plant, and their inventories were estimated. Rinsing water from etching process had the highest concentrations of copper (665.51 mg/L), lead (1.02 mg/L), nickel (3.60 mg/L), chromium (0.97 mg/L), and tin (1.79 mg/L). Powdered solid waste (SW) from the cut lamination process contained the highest tetrabromobisphenol-A (TBBPA) levels (49.86 mg/kg). Polybrominated diphenyl ethers (PBDEs) were absent in this plant, in agreement with the international regulations of PBDE phase out. The pollutant inventories in the wastes exhibited in the order of copper > > zinc > tin ≈ nickel > lead > chromium > > TBBPA. The potential environmental impact of pollutants in SW during production and disposal were further investigated. A high partitioning of pollutant concentration between the total suspended particle and SW (-0.10 leaching procedure, drilling powder with the smallest particle diameter still showed high leachabilities of lead and tin which may lead to a negative environmental impact during disposal. PMID:24777328

  10. Antimycobacterial brominated metabolites from two species of marine sponges.

    Science.gov (United States)

    de Oliveira, Maria Fernanda; de Oliveira, Jaine Honorata; Galetti, Fabio C; de Souza, Ana Olívia; Silva, Célio Lopes; Hajdu, Eduardo; Peixinho, Solange; Berlinck, Roberto G

    2006-04-01

    A screening of 500 crude extracts of marine invertebrates against the growth of Mycobacterium tuberculosis H37Rv yielded MeOH extracts of the sponges Aplysina cauliformis and Pachychalina sp. with significant activity. Further bioassay-guided fractionation of both crude extracts led to the isolation of four bromine-containing metabolites. The known (+)-fistularin-3 (1) and 11-deoxyfistularin-3 (2), and the new compound 2-(3-amino-2,4-dibromo-6-hydroxyphenyl)acetic acid (3) were isolated from the sponge A. cauliformis, while the new bromotyrosine-derived 3-(3,5-dibromo-4-methoxyphenyl)-2-methoxy- N-methylpropan-1-ammonium (4) was isolated from Pachychalina sp. Compound 4 exhibited weak antimycobacterial activity while compounds 1-3 displayed activity against Mycobacterium tuberculosis H37Rv, with MICs of 7.1, 7.3 and 49 microM, respectively. Compounds 1 and 2 also exhibited low cytotoxicity against J744 macrophages, indicating that both 1 and 2 are interesting leads for the development of new anti-tuberculosis agents. PMID:16557458

  11. Excited atomic bromine energy transfer and quenching mechanisms

    Science.gov (United States)

    Johnson, Ray O.

    1993-08-01

    Pulsed and steady-state photolysis experiments have been conducted to determine the rate coefficients for collisional deactivation of the spin-orbit excited state of atomic bromine, Br((sup 2)P(sub 1/2)). Pulsed lifetime studies for quenching by Br2 and CO2 established absolute rate coefficients at room temperature of k(sub Br2) = 1.2 +/- 0.1 x 10(exp-12) and k(sub CO2) = 1.5 +/0.2 x 10(exp-11) cu cm/molecule-s. Steady-state photolysis methods were used to determine the quenching rates for the rare gases, N2, 02, H2, D2, NO, NO2, N2O, SF6, CF4, CH4, CO, CO2, COS, SO2, H2S, HBr, HC1, and HI relative to that for Br2. Quenching rate temperature dependence was examined for Br2, CO2, N2O, HCl, COS, NO, and NO2 for temperatures from 300 to 420 K. Diffusion and three body effects were examined in order to determine the slowest relative quenching rate measurable by this experimental technique.

  12. Untypical bromine corrosion in boilers co-firing biomass

    Directory of Open Access Journals (Sweden)

    A. Hernas

    2012-09-01

    Full Text Available Purpose: The aim of this study was to determine the untypical corrosion resistance of rotary air preheaters in a biomass co-fired power plant.Design/methodology/approach: The selected results of some components of regenerative rotary air preheaters in a biomass co-fired power plant are presented. The macro and microstructure of corroded components of a LUVO preheater after 3 years of service are presented. The chemical composition of corrosion products was determined by X-ray microanalysis.Findings: Data concerning toxicity and identification of PBDEs (Polibrominated diphenyl ethers in the biomass is very limited. The presented research provides information and the proposed corrosion reaction mechanism in environments containing biomass with aggressive compounds like Cl, Si, H and Br.Research limitations/implications: An extended research on PBDEs in power plant fuels is necessary to give a full assessment of the corrosion mechanism in the presented environment; obligatory classification of the co-fired biomass.Originality/value: Firstly, an assessment of the danger for boiler materials co-firing biomass containing brominated organic flame and presentation of the reaction during the corrosion process and degradation of power boiler components in the presented environment. Secondly, the highlighting of the problem that there is a need to properly select and determine the chemical composition of the biomass used.

  13. Hydrogen cycle employing calcium-bromine and electrolysis

    International Nuclear Information System (INIS)

    The Secure Transportable Autonomous Reactor (STAR) project is part of the U.S. Department of Energy's (DOE's) Nuclear Energy Research Initiative (NERI) to develop Generation IV nuclear reactors that will supply high-temperature heat at over 800 C. The NERI project goal is to develop an economical, proliferation-resistant, sustainable, nuclear-based energy supply system based on a modular-sized fast reactor that is passively safe and cooled with heavy liquid metal. STAR consists of: (1) A combined thermochemical water-splitting cycle to generate hydrogen, (2) A steam turbine cycle to generate electricity, and (3) An optional capability to produce potable water from brackish or salt water. However, there has been limited reporting on critical elements of the thermochemical cycle: (1) establishing chemical reaction kinetics and operating pressures and (2) addressing materials issues for hydrogen production. This paper reviews the thermodynamic basis for a three-stage Calcium-Bromine water-splitting cycle based on the University of Tokyo Cycle No.3 [UT-3] and discusses the further chemistry work that is required to develop an economical process including modifying UT-3 to incorporate HBr dissociation

  14. Modelling chemistry over the Dead Sea: bromine and ozone chemistry

    Directory of Open Access Journals (Sweden)

    L. Smoydzin

    2009-02-01

    Full Text Available Measurements of O3 and BrO concentrations over the Dead Sea indicate that Ozone Depletion Events (ODEs, widely known to happen in polar regions, are also likely to occur over the Dead Sea due to the very high bromine content of the Dead Sea water. However, we show that BrO and O3 levels as they are detected cannot solely be explained by high Br levels in the Dead Sea water and the release of gas phase halogen species out of sea borne aerosol particles and their conversion to reactive halogen species. It is likely that other sources for reactive halogen compounds are needed to explain the observed concentrations for BrO and O3. To explain the chemical mechanism taking place over the Dead Sea leading to BrO levels of several pmol/mol we used the single column model MISTRA which calculates microphysics, meteorology, gas and aerosol phase chemistry. We performed pseudo Lagrangian studies by letting the model column first move over the desert which surrounds the Dead Sea region and then let it move over the Dead Sea itself. To include an additional source for gas phase halogen compounds, gas exchange between the Dead Sea water and the atmosphere is treated explicitly. Model calculations indicate that this process has to be included to explain the measurements.

  15. Modelling chemistry over the Dead Sea: bromine and ozone chemistry

    Directory of Open Access Journals (Sweden)

    R. von Glasow

    2009-07-01

    Full Text Available Measurements of O3 and BrO concentrations over the Dead Sea indicate that Ozone Depletion Events (ODEs, widely known to happen in polar regions, are also occuring over the Dead Sea due to the very high bromine content of the Dead Sea water. However, we show that BrO and O3 levels as they are detected cannot solely be explained by high Br levels in the Dead Sea water and the release of gas phase halogen species out of sea borne aerosol particles and their conversion to reactive halogen species. It is likely that other sources for reactive halogen compounds are needed to explain the observed concentrations for BrO and O3. To explain the chemical mechanism taking place over the Dead Sea leading to BrO levels of several pmol/mol we used the one-dimensional model MISTRA which calculates microphysics, meteorology, gas and aerosol phase chemistry. We performed pseudo Lagrangian studies by letting the model column first move over the desert which surrounds the Dead Sea region and then let it move over the Dead Sea itself. To include an additional source for gas phase halogen compounds, gas exchange between the Dead Sea water and the atmosphere is treated explicitly. Model calculations indicate that this process has to be included to explain the measurements.

  16. Non-polar halogenated natural products bioaccumulated in marine samples. II. Brominated and mixed halogenated compounds.

    Science.gov (United States)

    Vetter, Walter; Jun, Wu

    2003-07-01

    Several identified and potential natural brominated bioaccumulative compounds were studied in this work. 4,6-dibromo-2-(2('),4(')-dibromo)phenoxyanisole (BC-2) previously detected in Australian marine mammals and isolated from sponges, was synthesized. Two byproducts (a tetrabromo isomer and a tribromo congener) were investigated as well. The byproducts of the synthesis were not identified in the environmental samples investigated. Previously described natural brominated compounds (BC-1, BC-2, BC-3, BC-10, BC-11, MHC-1) and anthropogenic brominated diphenyl ethers (BDE-47, BDE-99, BDE-100, BDE-154) were detected in a sample of human milk. The sample was from a woman from the Faeroe Islands who frequently consumed fish as well as whale blubber and meat. The most abundant compound originated from the natural tetrabromo phenoxyanisole BC-3 which may have a 3:1 distribution of bromine on the two phenyl units. This sample also accumulated a dibromochloroanisole, as well as a previously unknown mixed halogenated compound (MHC-X) and an unknown, most likely aromatic brominated compound. Co-elutions on a DB-5 column were found for BDE-99 and BC-11 as well as BDE-154 and the unknown brominated compound. This suggests that quantification of these two compounds has to be carried out carefully.Two samples of lower trophic level, namely Baltic cod liver and Mexican mussel tissue, were investigated as well. The cod liver samples contained BDE congeners but also abundant signals for the natural 2,3,3('),4,4('),5,5(')-heptachloro-1(')-methyl-1,2(')-bipyrrole Q1 and tribromoanisole (TBA). The mussel sample contained Q1, TBA, another halogenated anisole, BC-1, BC-2, and BC-3, as well as additional, potential natural brominated compounds in the elution range of tribromophenoxyanisoles. PMID:12738265

  17. Impact of deep convection and dehydration on bromine loading in the upper troposphere and lower stratosphere

    Directory of Open Access Journals (Sweden)

    J. Aschmann

    2011-03-01

    Full Text Available Stratospheric bromine loading due to very short-lived substances is investigated with a three-dimensional chemical transport model over a period of 21 years using meteorological input data from the European Centre for Medium-Range Weather Forecasts ERA-Interim reanalysis from 1989 to the end of 2009. Within this framework we analyze the impact of dehydration and deep convection on the amount of stratospheric bromine using an idealized and a detailed full chemistry approach. We model the two most important brominated short-lived substances, bromoform (CHBr3 and dibromomethane (CH2Br2, assuming a uniform convective detrainment mixing ratio of 1 part per trillion by volume (pptv for both species. The contribution of very short-lived substances to stratospheric bromine varies drastically with the applied dehydration mechanism and the associated scavenging of soluble species ranging from 3.4 pptv in the idealized setup up to 5 pptv using the full chemistry scheme. In the latter case virtually the entire amount of bromine originating from very short-lived source gases is able to reach the stratosphere thus rendering the impact of dehydration and scavenging on inorganic bromine in the tropopause insignificant. Furthermore, our long-term calculations show that the mixing ratios of very short-lived substances are strongly correlated to convective activity, i.e. intensified convection leads to higher amounts of very short-lived substances in the upper troposphere/lower stratosphere especially under extreme conditions like El Niño seasons. However, this does not apply to the inorganic brominated product gases whose concentrations are anti-correlated to convective activity mainly due to convective dilution and possible scavenging, depending on the applied approach.

  18. Impact of deep convection and dehydration on bromine loading in the upper troposphere and lower stratosphere

    Directory of Open Access Journals (Sweden)

    J. Aschmann

    2011-01-01

    Full Text Available Stratospheric bromine loading due to very short-lived substances is investigated with a three-dimensional chemical transport model over a period of 21 years using meteorological input data from the European Centre for Medium-Range Weather Forecasts ERA-Interim reanalysis from 1989 to the end of 2009. Within this framework we analyze the impact of dehydration and deep convection on the amount of stratospheric bromine using an idealized and a detailed full chemistry approach. We model the two most important brominated short-lived substances, bromoform (CHBr3 and dibromomethane (CH2Br2, assuming a uniform detrainment mixing ratio of 1 part per trillion by volume (pptv for both species. The contribution of very short-lived substances to stratospheric bromine varies drastically with the applied dehydration mechanism and the associated scavenging of soluble species ranging from 3.4 pptv in the idealized setup up to 5 pptv using the full chemistry scheme. In the latter case virtually the entire amount of bromine originating from very short-lived source gases is able to reach the stratosphere thus rendering the impact of dehydration and scavenging on inorganic bromine in the tropopause insignificant. Furthermore, our long-term calculations show that the mixing ratios of very short-lived substances are strongly correlated to convective activity, i.e. intensified convection leads to higher amounts of very short-lived substances in the upper troposphere/lower stratosphere especially under extreme conditions like El Niño seasons. However, this does not apply to the inorganic brominated product gases whose concentrations are anti-correlated to convective activity mainly due to convective dilution and possible scavenging, depending on the applied approach.

  19. An exemplary case of a bromine explosion event linked to cyclone development in the Arctic

    Science.gov (United States)

    Blechschmidt, A.-M.; Richter, A.; Burrows, J. P.; Kaleschke, L.; Strong, K.; Theys, N.; Weber, M.; Zhao, X.; Zien, A.

    2016-02-01

    Intense, cyclone-like shaped plumes of tropospheric bromine monoxide (BrO) are regularly observed by GOME-2 on board the MetOp-A satellite over Arctic sea ice in polar spring. These plumes are often transported by high-latitude cyclones, sometimes over several days despite the short atmospheric lifetime of BrO. However, only few studies have focused on the role of polar weather systems in the development, duration and transport of tropospheric BrO plumes during bromine explosion events. The latter are caused by an autocatalytic chemical chain reaction associated with tropospheric ozone depletion and initiated by the release of bromine from cold brine-covered ice or snow to the atmosphere. In this manuscript, a case study investigating a comma-shaped BrO plume which developed over the Beaufort Sea and was observed by GOME-2 for several days is presented. By making combined use of satellite data and numerical models, it is shown that the occurrence of the plume was closely linked to frontal lifting in a polar cyclone and that it most likely resided in the lowest 3 km of the troposphere. In contrast to previous case studies, we demonstrate that the dry conveyor belt, a potentially bromine-rich stratospheric air stream which can complicate interpretation of satellite retrieved tropospheric BrO, is spatially separated from the observed BrO plume. It is concluded that weather conditions associated with the polar cyclone favoured the bromine activation cycle and blowing snow production, which may have acted as a bromine source during the bromine explosion event.

  20. Measurement-based modeling of bromine chemistry in the boundary layer: 1. Bromine chemistry at the Dead Sea

    Directory of Open Access Journals (Sweden)

    A. Pour Biazar

    2006-06-01

    Full Text Available The Dead Sea is an excellent natural laboratory for the investigation of Reactive Bromine Species (RBS chemistry, due to the high RBS levels observed in this area, combined with anthropogenic air pollutants up to several ppb. The present study investigated the chemical mechanism of RBS at the Dead Sea using a numerical one-dimensional chemical model. Simulations were based on data obtained from comprehensive measurements performed at sites along the Dead Sea. The simulations showed that the high BrO levels measured frequently at the Dead Sea could only partially be attributed to the highly concentrated Br− present in the Dead Sea water. Further, the RBS activity at the Dead Sea cannot solely be explained by a pure gas phase mechanism. This paper presents a chemical mechanism which can account for the observed chemical activity at the Dead Sea, with the addition of only two heterogeneous processes: the "Bromine Explosion" mechanism and the heterogeneous decomposition of BrONO2. Ozone frequently dropped below a threshold value of ~1 to 2 ppbv at the Dead Sea evaporation ponds, and in such cases, O3 became a limiting factor for the production of BrOx (BrO+Br. The entrainment of O3 fluxes into the evaporation ponds was found to be essential for the continuation of RBS activity, and to be the main reason for the positive correlation observed between BrO and O3 at low O3 concentrations, and for the jagged diurnal pattern of BrO observed in the Dead Sea area. The present study has shown that the heterogeneous decomposition of BrONO2 has the potential to greatly affect the RBS activity in areas under anthropogenic influence, mainly due to the positive correlation between the rate of this process and the levels of NO2. Further investigation of the influence of the decomposition of BrONO2 may be especially important in understanding the RBS activity at mid-latitudes.

  1. Measurement-based modeling of bromine chemistry in the boundary layer: 1. Bromine chemistry at the Dead Sea

    Directory of Open Access Journals (Sweden)

    E. Tas

    2006-01-01

    Full Text Available The Dead Sea is an excellent natural laboratory for the investigation of Reactive Bromine Species (RBS chemistry, due to the high RBS levels observed in this area, combined with anthropogenic air pollutants up to several ppb. The present study investigated the basic chemical mechanism of RBS at the Dead Sea using a numerical one-dimensional chemical model. Simulations were based on data obtained from comprehensive measurements performed at sites along the Dead Sea. The simulations showed that the high BrO levels measured frequently at the Dead Sea could only partially be attributed to the highly concentrated Br− present in the Dead Sea water. Furthermore, the RBS activity at the Dead Sea cannot solely be explained by a pure gas phase mechanism. This paper presents a chemical mechanism which can account for the observed chemical activity at the Dead Sea, with the addition of only two heterogeneous processes: the "Bromine Explosion" mechanism and the heterogeneous decomposition of BrONO2. Ozone frequently dropped below a threshold value of ~1 to 2 ppbv at the Dead Sea evaporation ponds, and in such cases, O3 became a limiting factor for the production of BrOx (BrO+Br. The entrainment of O3 fluxes into the evaporation ponds was found to be essential for the continuation of RBS activity, and to be the main reason for the jagged diurnal pattern of BrO observed in the Dead Sea area, and for the positive correlation observed between BrO and O3 at low O3 concentrations. The present study has shown that the heterogeneous decomposition of BrONO2 has a great potential to affect the RBS activity in areas influenced by anthropogenic emissions, mainly due to the positive correlation between the rate of this process and the levels of NO2. Further investigation of the influence of the decomposition of BrONO2 may be especially important in understanding the RBS activity at mid-latitudes.

  2. 45 CFR 79.5 - Review by the reviewing official.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Review by the reviewing official. 79.5 Section 79... REMEDIES § 79.5 Review by the reviewing official. (a) If, based on the report of the investigating official under § 79.4(b), the reviewing official determines that there is adequate evidence to believe that...

  3. Absorption and biotransformation of polybrominated diphenyl ethers DE-71 and DE-79 in chicken (Gallus gallus), mallard (Anas platyrhynchos), American kestrel (Falco sparverius) and black-crowned night-heron (Nycticorax nycticorax) eggs

    Science.gov (United States)

    McKernan, Moira A.; Rattner, Barnett A.; Hatfield, Jeff S.; Hale, Robert C.; Ottinger, Mary Ann

    2010-01-01

    We recently reported that air cell administration of penta-brominated diphenyl ether (penta-BDE; DE-71) evokes biochemical and immunologic effects in chicken (Gallus gallus) embryos at very low doses, and impairs pipping (i.e., stage immediately prior to hatching) and hatching success at 1.8 ug g-1 egg (actual dose absorbed) in American kestrels (Falco sparverius). I n the present study, absorption of polybrominated diphenyl ether (PBDE) congeners was measured following air cell administration of a penta-BDE mixture (11.1 ug DE-71 g-1 egg) or an octa-brominated diphenyl ether mixture (octa-BDE; DE-79; 15.4 ug DE-79 g-1 egg). Uptake of PBDE congeners was measured at 24 h post-injection, midway through incubation, and at pipping in chicken, mallard (Anas platyrhynchos), and American kestrel egg contents, and at the end of incubation in black-crowned night-heron (Nycticorax nycticorax) egg contents. Absorption of penta-BDE and octa-BDE from the air cell into egg contents occurred throughout incubation; at pipping, up to 29.6% of penta-BDE was absorbed, but only 1.40-6.48% of octa-BDE was absorbed. Higher brominated congeners appeared to be absorbed more slowly than lower brominated congeners, and uptake rate was inversely proportional to the log Kow of predominant BDE congeners. Six congeners or co-eluting pairs of congeners were detected in penta-BDE-treated eggs that were not found in the dosing solution suggesting debromination in the developing embryo, extraembryonic membranes, and possibly even in the air cell membrane. This study demonstrates the importance of determining the fraction of xenobiotic absorbed into the egg following air cell administration for estimation of the lowest-observed-effect level.

  4. Brominated skeletal components of the marine demosponges, Aplysina cavernicola and Ianthella basta: analytical and biochemical investigations.

    Science.gov (United States)

    Kunze, Kurt; Niemann, Hendrik; Ueberlein, Susanne; Schulze, Renate; Ehrlich, Hermann; Brunner, Eike; Proksch, Peter; van Pée, Karl-Heinz

    2013-04-01

    Demosponges possess a skeleton made of a composite material with various organic constituents and/or siliceous spicules. Chitin is an integral part of the skeleton of different sponges of the order Verongida. Moreover, sponges of the order Verongida, such as Aplysina cavernicola or Ianthella basta, are well-known for the biosynthesis of brominated tyrosine derivates, characteristic bioactive natural products. It has been unknown so far whether these compounds are exclusively present in the cellular matrix or whether they may also be incorporated into the chitin-based skeletons. In the present study, we therefore examined the skeletons of A. cavernicola and I. basta with respect to the presence of bromotyrosine metabolites. The chitin-based-skeletons isolated from these sponges indeed contain significant amounts of brominated compounds, which are not easily extractable from the skeletons by common solvents, such as MeOH, as shown by HPLC analyses in combination with NMR and IR spectroscopic measurements. Quantitative potentiometric analyses confirm that the skeleton-associated bromine mainly withstands the MeOH-based extraction. This observation suggests that the respective, but yet unidentified, brominated compounds are strongly bound to the sponge skeletons, possibly by covalent bonding. Moreover, gene fragments of halogenases suggested to be responsible for the incorporation of bromine into organic molecules could be amplified from DNA isolated from sponge samples enriched for sponge-associated bacteria. PMID:23595055

  5. Removal of brominated flame retardant from electrical and electronic waste plastic by solvothermal technique

    International Nuclear Information System (INIS)

    Highlights: ► A process for brominated flame retardants (BFRs) removal in plastic was established. ► The plastic became bromine-free with the structure maintained after this treatment. ► BFRs transferred into alcohol solvent were easily debrominated by metallic copper. - Abstract: Brominated flame retardants (BFRs) in electrical and electronic (E and E) waste plastic are toxic, bioaccumulative and recalcitrant. In the present study, tetrabromobisphenol A (TBBPA) contained in this type of plastic was tentatively subjected to solvothermal treatment so as to obtain bromine-free plastic. Methanol, ethanol and isopropanol were examined as solvents for solvothermal treatment and it was found that methanol was the optimal solvent for TBBPA removal. The optimum temperature, time and liquid to solid ratio for solvothermal treatment to remove TBBPA were 90 °C, 2 h and 15:1, respectively. After the treatment with various alcohol solvents, it was found that TBBPA was finally transferred into the solvents and bromine in the extract was debrominated catalyzed by metallic copper. Bisphenol A and cuprous bromide were the main products after debromination. The morphology and FTIR properties of the plastic were generally unchanged after the solvothermal treatment indicating that the structure of the plastic maintained after the process. This work provides a clean and applicable process for BFRs-containing plastic disposal.

  6. Electrochemical performance and transport properties of a Nafion membrane in a hydrogen-bromine cell environment

    Science.gov (United States)

    Baldwin, Richard S.

    1987-01-01

    The overall energy conversion efficiency of a hydrogen-bromine energy storage system is highly dependent upon the characteristics and performance of the ion-exchange membrane utilized as a half-cell separator. The electrochemical performance and transport properties of a duPont Nafion membrane in an aqueous HBr-Br2 environment were investigated. Membrane conductivity data are presented as a function of HBr concentration and temperature for the determination of ohmic voltage losses across the membrane in an operational cell. Diffusion-controlled bromine permeation rates and permeabilities are presented as functions of solution composition and temperature. Relationships between the degree of membrane hydration and the membrane transport characteristics are discussed. The solution chemistry of an operational hydrogen-bromine cell undergoing charge from 45% HBr to 5% HBr is discussed, and, based upon the experimentally observed bromine permeation behavior, predicted cell coulombic losses due to bromine diffusion through the membrane are presented as a function of the cell state-of-charge.

  7. The bromine enhancement ratio in mammalian cells in vitro and experimental mouse tumours

    International Nuclear Information System (INIS)

    Human kidney cells in culture and cells of mouse sarcoma-180 were allowed to incorporate bromine into their DNA. Cultured cells with and without incorporated BUdR were irradiated with electromagnetic radiations ranging in energy from 12 keV X-rays to 60Co γ-rays to find out whether or not there exists any energy dependence of the bromine dose enhancement ratio BER. Such a dependence should show in the immediate neighbourhood of the K-absorption edge of bromine (13.5 keV). Any influence of the Auger effect triggered in bromine by external irradiation should show by a significant increase of the BER for energies rising from slightly below to slight above the bromine K-edge. Values of D37, D0 and the extrapolation numbers of the cell survival curves served as biological endpoints. Measured values of BER ranged from 1.12-2.00 without any significant dependence on energy. A weakly pronounced peak was found for 50 kV X-rays of 26 keV mean energy. Sarcoma-180 were irradiated with 14 keV X-rays and 60C γ-rays. BUdR was administered i.v., i.p. and directly into the tumours in quantities of up to 1 ml of a 10-3M solution. (Auth.)

  8. Bromine and bromide content in soils: Analytical approach from total reflection X-ray fluorescence spectrometry.

    Science.gov (United States)

    Gallardo, Helena; Queralt, Ignasi; Tapias, Josefina; Candela, Lucila; Margui, Eva

    2016-08-01

    Monitoring total bromine and bromide concentrations in soils is significant in many environmental studies. Thus fast analytical methodologies that entail simple sample preparation and low-cost analyses are desired. In the present work, the possibilities and drawbacks of low-power total reflection X-ray fluorescence spectrometry (TXRF) for the determination of total bromine and bromide contents in soils were evaluated. The direct analysis of a solid suspension using 20 mg of fine ground soil (water soil extracts. In this case, the TXRF analysis can be directly performed by depositing 10 μL of the internal standardized soil extract sample on a quartz glass reflector in a measuring time of 1500 s. The bromide limit of detection by this approach was 10 μg L(-1). Good agreement was obtained between the TXRF results for the total bromine and bromide determinations in soils and those obtained by other popular analytical techniques, e.g. energy dispersive X-ray fluorescence spectrometry (total bromine) and ionic chromatography (bromide). As a study case, the TXRF method was applied to study bromine accumulation in two agricultural soils fumigated with a methyl bromide pesticide and irrigated with regenerated waste water. PMID:27179429

  9. Brominated Skeletal Components of the Marine Demosponges, Aplysina cavernicola and Ianthella basta: Analytical and Biochemical Investigations

    Directory of Open Access Journals (Sweden)

    Eike Brunner

    2013-04-01

    Full Text Available Demosponges possess a skeleton made of a composite material with various organic constituents and/or siliceous spicules. Chitin is an integral part of the skeleton of different sponges of the order Verongida. Moreover, sponges of the order Verongida, such as Aplysina cavernicola or Ianthella basta, are well-known for the biosynthesis of brominated tyrosine derivates, characteristic bioactive natural products. It has been unknown so far whether these compounds are exclusively present in the cellular matrix or whether they may also be incorporated into the chitin-based skeletons. In the present study, we therefore examined the skeletons of A. cavernicola and I. basta with respect to the presence of bromotyrosine metabolites. The chitin-based-skeletons isolated from these sponges indeed contain significant amounts of brominated compounds, which are not easily extractable from the skeletons by common solvents, such as MeOH, as shown by HPLC analyses in combination with NMR and IR spectroscopic measurements. Quantitative potentiometric analyses confirm that the skeleton-associated bromine mainly withstands the MeOH-based extraction. This observation suggests that the respective, but yet unidentified, brominated compounds are strongly bound to the sponge skeletons, possibly by covalent bonding. Moreover, gene fragments of halogenases suggested to be responsible for the incorporation of bromine into organic molecules could be amplified from DNA isolated from sponge samples enriched for sponge-associated bacteria.

  10. Human health risk associated with brominated flame-retardants (BFRs).

    Science.gov (United States)

    Lyche, Jan L; Rosseland, Carola; Berge, Gunnar; Polder, Anuschka

    2015-01-01

    The purposes of this review are to assess the human exposure and human and experimental evidence for adverse effects of brominated flame-retardants (BFRs) with specific focus on intake from seafood. The leakage of BFRs from consumer products leads to exposure of humans from fetal life to adulthood. Fish and fish products contain the highest levels of BFRs and dominate the dietary intake of frequent fish eaters in Europe, while meat, followed by seafood and dairy products accounted for the highest US dietary intake. House dust is also reported as an important source of exposure for children as well as adults. The levels of BFRs in the general North American populations are higher than those in Europe and Japan and the highest levels are detected in infants and toddlers. The daily intake via breast milk exceeds the RfD in 10% of US infants. BFRs including PBDEs, HBCDs and TBBP-A have induced endocrine-, reproductive- and behavior effects in laboratory animals. Furthermore, recent human epidemiological data demonstrated association between exposure to BFRs and similar adverse effects as observed in animal studies. Fish including farmed fish and crude fish oil for human consumption may contain substantial levels of BFRs and infants and toddlers consuming these products on a daily basis may exceed the tolerable daily intake suggesting that fish and fish oil alone represent a risk to human health. This intake comes in addition to exposure from other sources (breast milk, other food, house dust). Because potential harmful concentrations of BFRs and other toxicants occur in fish and fish products, research on a wider range of products is warranted, to assess health hazard related to the contamination of fish and fish products for human consumption. PMID:25454234

  11. Determination of bromine contents in blood and hair of workers exposed to methyl by radioactivation analysis method bromide

    International Nuclear Information System (INIS)

    The bromine contained in blood and hair samples obtained from workers exposed to methyl bromide was analyzed by nondestructive activation analysis. The samples were irradiated for 1 min in pneumatic irradiation facility of Kyoto University research reactor with an estimated thermal neutron flux density at 2 x 1013 n.cm-2.sec-1. The irradiation was counted with Ge(Li) detector. The duration of measurement of radionuclide bromine in blood and hair was 200 sec within 2 - 10 min after irradiation. The bromine content of serum sample obtained from a worker suspected of methyl bromide poisoning was found to be 412 μg/g on 13 days apart from exposure to methyl bromide. The biological half-life of bromine in this case was found to be about 16 days. Then bromine contents in serum and hair samples obtained from workers exposed to methyl bromide were found to be 1.7 and 2.6 times higher respectively than those of nonexposed workers. Any correlations of bromine contents were not observed between serum and hair samples obtained from workers exposed to methyl bromide, nor between bromine amount in the serum of workers exposed to methyl bromide and the terms exposed to it, but statistically significant positive correlation was observed between bromine amount in the hair of workers exposed to methyl bromide and the terms exposed to it. (author)

  12. Determination by neutron activation analysis of loss of arsenic, antimony, bromine and mercury during lyophilization

    International Nuclear Information System (INIS)

    Neutron activation analysis has been used to monitor the loss of arsenic, as dimethylarsinic acid, (CH3)2AsOOH, or as sodium arsenate (Na2HAsO4.7H2O), antimony (as potassium antimony, tartrate, KSbC4O7.1/2H2O) and bromine (as bromide ion) during lyophilization of acidified and neutral aqueous synthetic and environmental samples. Losses of Sb and As ranged from zero to 60%, while losses of bromine were constant (at 91%) in acidic solutions. The variable losses of As and Sb were due solely to the presence of and partial decomposition of the (CH3)2AsOOH. Electrochemical oxidation of Br- to Br2 is responsible for the high losses of bromine. In addition losses of mercury (as methylmercuric chloride) were 1O0% in both acidic and neutral aqueous synthetic samples during lyophilization. (author)

  13. Leaching characteristics of heavy metals and brominated flame retardants from waste printed circuit boards

    International Nuclear Information System (INIS)

    Highlights: ► Cu and Pb were the most leachable heavy metals in WPCBs according to TCLP and SPLP. ► Penta-BDE congeners were dominated in all extracts. ► High dissolved organic matter condition promoted the BFRs leaching rate. ► Leaching from WPCBs was a significant emission source of BFRs in landfill. -- Abstract: Leaching assessment on five heavy metals (copper, zinc, lead, nickel and cadmium) and two brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA), from waste printed circuit boards (WPCBs) were conducted using various leaching methods. The mean leaching concentrations of copper were the highest in both toxicity characteristic leaching procedures (TCLP) and synthetic precipitation leaching procedures (SPLP) tests at 8.6 mg/L and 1.1 mg/L, while only lead (6.2 mg/L) exceeded the TCLP criteria and Chinese EPA regulatory limit (both 5.0 mg/L). However, PBDEs and TBBPA were not detected in TCLP and SPLP tests. Then the BFRs leaching trends and potential leachabilities were further investigated in actual landfill leachates using a modified method. Leaching characteristics that fast-leaching initially followed by slow-desorption over time were generally observed. In landfill leachate tests, the highest leaching concentrations of PBDEs and TBBPA were determined at 30.39 and 12.27 μg/L. Meanwhile, the highest leaching rates were estimated to reach 0.08% and 1.00%, respectively, which were significantly influenced by the dissolved organic carbon contents of extracts, the hydrophobicities of target BFRs and the specific surface areas of WPCBs materials. These results proved that leaching from WPCBs was a significant emission source of BFRs in landfill and electronic waste recycling dumpsite

  14. Coulomb excitation of radioactive {sup 79}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Lister, C.J.; Blumenthal, D.; Davids, C.N. [and others

    1995-08-01

    The technical challenges expected in experiments with radioactive beams can already be explored by using ions produced in primary reactions. In addition, the re-excitation of these ions by Coulomb excitation allows a sensitive search for collective states that are well above the yrast line. We are building an experiment to study Coulomb excitation of radioactive ions which are separated from beam particles by the Fragment Mass Analyzer. An array of gamma detectors will be mounted at the focal plane to measure the gamma radiation following re-excitation. Five Compton-suppressed Ge detectors and five planar LEPS detectors will be used. The optimum experiment of this type appears to be the study of {sup 79}Rb following the {sup 24}Mg ({sup 58}Ni,3p) reaction. We calculate that about 5 x 10{sup 5} {sup 79}Rb nuclei/second will reach the excitation foil. This rubidium isotope was selected for study as it is strongly produced and is highly deformed, so easily re-excited. The use of a {sup 58}Ni re-excitation foil offers the best yields. After re-excitation the ions will be subsequently transported into a shielded beamdump to prevent the accumulation of activity.

  15. Regional variation and possible sources of brominated contaminants in breast milk from Japan

    International Nuclear Information System (INIS)

    This study focuses on the regional trends and possible sources of brominated organic contaminants accumulated in breast milk from mothers in southeastern (Okinawa) and northwestern (Hokkaido) areas of Japan. For persistent brominated flame retardants, polybrominated diphenyl ethers (PBDEs; major components, BDE-47 and BDE-153) were distributed at higher levels in mothers from Okinawa (mean, 2.1 ng/g lipid), while hexabromobenzene (HeBB) and its metabolite 1,2,4,5-tetrabromobenzene were more abundantly detected in mothers from Hokkaido (0.86 and 2.6 ng/g lipid), suggesting that there are regional differences in their exposure in Japan. We also detected naturally produced brominated compounds, one of which was identified as 2′-methoxy-2,3′,4,5′-tetrabromodiphenyl ether (2′-MeO-BDE68) at higher levels in mothers from Okinawa (0.39 ng/g lipid), while the other was identified as 3,3′,4,4′-tetrabromo-5,5′-dichloro-2,2′-dimethyl-1,1′-bipyrrole in mothers from Hokkaido (0.45 ng/g lipid). The regional variation may be caused by source differences, i.e. southern seafood for MeO-PBDEs and northern biota for halogenated bipyrroles in the Japanese coastal water. - Highlights: ► In this study, we detected brominated organic contaminants in Japanese breast milk. ► Naturally produced brominated organic contaminants were also detected. ► Northern and southern Japan showed regional differences in these contaminants. ► Exposure to the contaminants is suggested to arise from different specific sources. - Brominated organic contaminants were detected in Japanese breast milk.

  16. Dichlorinated and Brominated Rugulovasines, Ergot Alkaloids Produced by Talaromyces wortmannii

    DEFF Research Database (Denmark)

    Soman De Medeiros, Lívia; da Silva, José Vinícius; Abreu, Lucas Magalhães;

    2015-01-01

    . Brominated rugulovasines were also detected when the microbial incubation medium was supplemented with bromine sources. Studies from 1D/2D NMR and HRMS spectroscopy data allowed the structural elucidation of the dichlorinated compounds, while tandem MS/HRMS data analysis supported the rationalization of......UHPLC-DAD-HRMS based dereplication guided the detection of new halogenated alkaloids co-produced by Talaromyces wortmannii. From the fungal growth in large scale, the epimers 2,8-dichlororugulovasines A and B were purified and further identified by means of a HPLC-SPE/NMR hyphenated system...

  17. Photochemical bromination of substituted indan-1-one derivatives: synthesis of new polybromoindan-1-one derivatives

    OpenAIRE

    KUŞ, Nermin Şimşek

    2009-01-01

    The photobromination of substituted indan derivatives was studied. Four products, 2,3-dibromo-inden-1-one (5), trans-2,3-dibromoindan-1-one (6), 2,2-dibromoindan-1,3-dione (7) and 2,2-dibromoindan-1-one (8), were obtained by the bromination of indan-1-one (4). The bromination of 2-methyl indanone (9) and 3-methyl-indanone (13) gave the corresponding monobromo, dibromo, and tribromo compounds in high yield. 4-Nitro indan (16) was tribrominated under same condition reaction. The stru...

  18. Effect of Brominated Furanones on the Formation of Biofilm by Escherichia coli on Polyvinyl Chloride Materials

    OpenAIRE

    Lianhua, Ye; Yunchao, Huang; Geng, Xu; Youquang, Zhou; Guangqiang, Zhao; Yujie, Lei

    2013-01-01

    To study the influence of brominated furanones on the biofilm (BF) formation by Escherichia coli (E. coli) on polyvinyl chloride (PVC) material, and to provide new ways of surface modification of materials to clinically prevent biomaterial centered infection. Three brominated furanones, dissolved in ethanol, furanone-1(3,4-dibromo-5-hydroxyl-furanone), furanone-2(4-bromo-5-(4-methoxypheny)-3-(methylamino)-furanone), and furanone-3(3,4-dibromo-5,5-dimethoxypheny-2(5H)-furanone) with representa...

  19. 45 CFR 81.79 - Cross-examination.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Cross-examination. 81.79 Section 81.79 Public... UNDER PART 80 OF THIS TITLE Hearing Procedures § 81.79 Cross-examination. A witness may be cross-examined on any matter material to the proceeding without regard to the scope of his direct examination....

  20. 48 CFR 1511.011-79 - Information resources management.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Information resources management. 1511.011-79 Section 1511.011-79 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY ACQUISITION PLANNING DESCRIBING AGENCY NEEDS 1511.011-79 Information resources management....

  1. Calculation of half-life for 79Se decay

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The half-life for 79Se decay is calculated by using the Logf1ut systematics method. Based on the data analysis and comparison with experimental data the 79Se half-life is recommended. The scheme for 79Se decay is also shown and the radiation data are calculated in the text.

  2. 40 CFR 79.68 - Salmonella typhimurium reverse mutation assay.

    Science.gov (United States)

    2010-07-01

    ... recommendations as specified under 40 CFR 79.60, the following specific information shall be reported: (i... consulted. (1) 40 CFR 798.5265, The Salmonella typhimurium reverse mutation asay. (2) Ames, B.N., McCann, J... mutation assay. 79.68 Section 79.68 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  3. Regioselective chlorination and bromination of unprotected anilines under mild conditions using copper halides in ionic liquids

    OpenAIRE

    Han Wang; Kun Wen; Nurbiya Nurahmat; Yan Shao; He Zhang; Chao Wei; Ya Li; Yongjia Shen; Zhihua Sun

    2012-01-01

    By using ionic liquids as solvents, the chlorination or bromination of unprotected anilines at the para-position can be achieved in high yields with copper halides under mild conditions, without the need for potentially hazardous operations such as supplementing oxygen or gaseous HCl.

  4. Regioselective chlorination and bromination of unprotected anilines under mild conditions using copper halides in ionic liquids

    Directory of Open Access Journals (Sweden)

    Han Wang

    2012-05-01

    Full Text Available By using ionic liquids as solvents, the chlorination or bromination of unprotected anilines at the para-position can be achieved in high yields with copper halides under mild conditions, without the need for potentially hazardous operations such as supplementing oxygen or gaseous HCl.

  5. Kinetics of aerobic cometabolic biodegradation of chlorinated and brominated aliphatic hydrocarbons: A review.

    Science.gov (United States)

    Jesus, João; Frascari, Dario; Pozdniakova, Tatiana; Danko, Anthony S

    2016-05-15

    This review analyses kinetic studies of aerobic cometabolism (AC) of halogenated aliphatic hydrocarbons (HAHs) from 2001-2015 in order to (i) compare the different kinetic models proposed, (ii) analyse the estimated model parameters with a focus on novel HAHs and the identification of general trends, and (iii) identify further research needs. The results of this analysis show that aerobic cometabolism can degrade a wide range of HAHs, including HAHs that were not previously tested such as chlorinated propanes, highly chlorinated ethanes and brominated methanes and ethanes. The degree of chlorine mineralization was very high for the chlorinated HAHs. Bromine mineralization was not determined for studies with brominated aliphatics. The examined research period led to the identification of novel growth substrates of potentially high interest. Decreasing performance of aerobic cometabolism were found with increasing chlorination, indicating the high potential of aerobic cometabolism in the presence of medium- and low-halogenated HAHs. Further research is needed for the AC of brominated aliphatic hydrocarbons, the potential for biofilm aerobic cometabolism processes, HAH-HAH mutual inhibition and the identification of the enzymes responsible for each aerobic cometabolism process. Lastly, some indications for a possible standardization of future kinetic studies of HAH aerobic cometabolism are provided. PMID:26874310

  6. Performance and Degradation of A Lithium-Bromine Rechargeable Fuel Cell Using Highly Concentrated Catholytes

    CERN Document Server

    Bai, Peng

    2016-01-01

    Lithium-air batteries have been considered as ultimate solutions for the power source of long-range electrified transportation, but state-of-the-art prototypes still suffer from short cycle life, low efficiency and poor power output. Here, a lithium-bromine rechargeable fuel cell using highly concentrated bromine catholytes is demonstrated with comparable specific energy, improved power density, and higher efficiency. The cell is similar in structure to a hybrid-electrolyte Li-air battery, where a lithium metal anode in nonaqueous electrolyte is separated from aqueous bromine catholytes by a lithium-ion conducting ceramic plate. The cell with a flat graphite electrode can discharge at a peak power density around 9mW cm-2 and in principle could provide a specific energy of 791.8 Wh kg-1, superior to most existing cathode materials and catholytes. It can also run in regenerative mode to recover the lithium metal anode and free bromine with 80-90% voltage efficiency, without any catalysts. Degradation of the sol...

  7. On the bromination of the dihydroazulene/vinylheptafulvene photo-/thermoswitch

    DEFF Research Database (Denmark)

    Mazzanti, Virginia; Cacciarini, Martina; Broman, Søren Lindbæk;

    2012-01-01

    Background: The dihydroazulene (DHA)/vinylheptafulvene (VHF) system (with two cyano groups at C1) functions as a photo-/thermoswitch. Direct ionic bromination of DHA has previously furnished a regioselective route to a 7,8-dibromide, which by elimination was converted to a 7-bromo-substituted DHA...

  8. Photothermally induced bromination of carbon/polymer bipolar plate materials for fuel cell applications

    Science.gov (United States)

    Schade, Martin; Franzka, Steffen; Cappuccio, Franco; Peinecke, Volker; Heinzel, Angelika; Hartmann, Nils

    2015-05-01

    A facile photothermal procedure for direct functionalization of carbon/polymer bipolar plate materials is demonstrated. Through irradiation with a microfocused beam of an Ar+-laser at λ = 514 nm in gaseous bromine and distinct laser powers and pulse lengths local bromination of the carbon/polymer material takes place. At a 1/e spot diameter of 2.1 μm, functionalized surface areas with diameters down to 5 μm are fabricated. In complementary experiments large-area bromination is investigated using an ordinary tungsten lamp. For characterization contact angle goniometry, X-ray photoelectron spectroscopy and electron microscopy in conjunction with labeling techniques are employed. After irradiation bromine groups can easily be substituted by other chemical functionalities, e.g. azide and amine groups. This provides a facile approach in order to fabricate surface patterns and gradient structures with varying wetting characteristics. Mechanistic aspects and prospects of photothermal routines in micropatterning of carbon/polymer materials are discussed.

  9. Bromine-82 Labelling of Human Serum Albumin, Insulin and Fibrinogen by Electrochemical Means

    International Nuclear Information System (INIS)

    The authors describe results obtained with a method using bromine-82 to label human serum albumin, fibrinogen and insulin, three organic substances of special importance in diagnostics and biological research. The method involves electrolytic bromination in an aqueous solution; this is performed in an electrolysis cell, whose anodic zone containing the substance to be labelled is partitioned from the cathodic zone by a dialysis membrane. For each of the three substances mentioned, the degree of bromination produced by a direct current (200, 200, 300 x 10-6 Å) was studied as a function of anode potential in 10-3 and 10-4 M solutions of NH4Br, the amount of bromine-labelled substance formed being checked by radio electrophoresis for various anodic potential values differing from each other by 50 mV. By immuno- electrophoresis it was ascertained that denaturation of albumin and fibrinogen only starts at anodic potential values for which the degree of labelling is already very high as compared with that yielded by chemical methods of labelling. The method here described has the advantage of rapid execution and is well suited to remote handling in a shielded zone. (author)

  10. Electron stimulated desorption of anions from native and brominated single stranded oligonucleotide trimers

    Energy Technology Data Exchange (ETDEWEB)

    Polska, Katarzyna; Rak, Janusz [Department of Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Bass, Andrew D.; Cloutier, Pierre; Sanche, Leon [Research Group in the Radiation Sciences, Faculty of Medicine, Universite de Sherbrooke, Sherbrooke, Quebec J1H 5N4 (Canada)

    2012-02-21

    We measured the low energy electron stimulated desorption (ESD) of anions from thin films of native (TXT) and bromine monosubstituted (TBrXT) oligonucleotide trimers deposited on a gold surface (T = thymidine, X = T, deoxycytidine (C), deoxyadenosine (A) or deoxyguanosine (G), Br = bromine). The desorption of H{sup -}, CH{sub 3}{sup -}/NH{sup -}, O{sup -}/NH{sub 2}{sup -}, OH{sup -}, CN{sup -}, and Br{sup -} was induced by 0 to 20 eV electrons. Dissociative electron attachment, below 12 eV, and dipolar dissociation, above 12 eV, are responsible for the formation of these anions. The comparison of the results obtained for the native and brominated trimers suggests that the main pathways of TBrXT degradation correspond to the release of the hydride and bromide anions. Significantly, the presence of bromine in oligonucleotide trimers blocks the electron-induced degradation of nuclobases as evidenced by a dramatic decrease in CN{sup -} desorption. An increase in the yields of OH{sup -} is also observed. The debromination yield of particular oligonucleotides diminishes in the following order: BrdU > BrdA > BrdG > BrdC. Based on these results, 5-bromo-2{sup '}-deoxyuridine appears to be the best radiosensitizer among the studied bromonucleosides.

  11. Assessment of the zinc-bromine battery for utility load leveling. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Will, F. G.; Iacovangelo, C. D.; Jackowski, J. S.; Secor, F. W.

    1978-03-15

    The technical and economic prospects of zinc-bromine batteries employing Nafion/sup R*/ fluorinated ion exchange membranes was evaluated. The applicability and performance limits of a variety of materials and concepts were explored, noval all-carbon electrode structures developed and tested in cells of up to 36 w-hr size, and a system design and cost analysis was performed.

  12. Biodegradation of brominated aromatics by cultures and laccase of Trametes versicolor

    Czech Academy of Sciences Publication Activity Database

    Uhnáková, Bronislava; Petříčková, Alena; Biedermann, David; Homolka, Ladislav; Vejvoda, Vojtěch; Bednář, P.; Papoušková, B.; Šulc, Miroslav; Martínková, Ludmila

    2009-01-01

    Roč. 76, č. 6 (2009), s. 826-832. ISSN 0045-6535 R&D Projects: GA MŠk 2B06151 Institutional research plan: CEZ:AV0Z50200510 Keywords : Brominated phenols * Tetrabromobisphenol A * Laccase Subject RIV: CE - Biochemistry Impact factor: 3.253, year: 2009

  13. Thermoelectric properties of bromine filled CoSb3 skutterudite

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, Brenden R.; Crawford, Caitlin M.; McKinney, Robert W.; Parilla, Philip A.; Toberer, Eric S.

    2016-01-01

    Historically, the improved thermoelectric performance of skutterudite compounds has largely been driven by the incorporation of electropositive donors on interstitial sites. These 'rattlers' serve to optimize both electronic and thermal properties by tuning the carrier concentration and scattering phonons. In this work, we show that interstitial bromine can be incorporated into CoSb3 and assess the impact on electronic and thermal transport. In contrast to prior high pressure syntheses with iodine, interstitial bromine incorporation is achieved at ambient pressure. Transport properties are stable up to at least 375 degrees C. Bromine serves as an electronegative acceptor and can induce degenerate (>5 x 1019 cm-3) hole densities. In contrast to other p-type skutterudite compositions, bromine preserves the intrinsically high hole mobility of CoSb3 while significantly reducing the lattice thermal conductivity. The development of a stable p-type dopant for the interstitial filler site enables the development of skutterudites with both donor and acceptor interstitials to maximize phonon scattering while maintaining the high mobility of CoSb3.

  14. XAS AND XPS CHARACTERIZATION OF MERCURY BINDING ON BROMINATED ACTIVATED CARBON

    Science.gov (United States)

    Brominated powdered activated carbon sorbents have been shown to e quite effective for mercury capture when injected into the flue gas duct at coal-fired power plants and are especially useful when buring Western low-chlorine subbituminous coals. X-ray absorption spectroscopy (X...

  15. Ullmann-type coupling of brominated tetrathienoanthracene on copper and silver

    Czech Academy of Sciences Publication Activity Database

    Gutzler, R.; Cardenas, L.; Lipton-Duffin, J.; El Garah, M.; Dinca, L.E.; Szakacs, C.E.; Fu, Ch.; Gallagher, M.; Vondráček, Martin; Rybachuk, M.; Perepichka, D.F.; Rosei, F.

    2014-01-01

    Roč. 6, č. 5 (2014), 2660-2668. ISSN 2040-3364 R&D Projects: GA MŠk(CZ) LM2011029 Institutional support: RVO:68378271 Keywords : Ullmann reaction * brominated tetrathienoanthracene * high resolution photoemission * STM Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.394, year: 2014

  16. Surface characteristics of photoaligned polyimide film interfacial reacted with bromine or ethanethiol

    International Nuclear Information System (INIS)

    The surface characteristics of polyimide films containing cinnamate groups which promote the uniform alignment in adjacent liquid crystal (LC) upon photodimerization by linearly polarized ultraviolet (LPUV) lights were studied [M. Schadt, K. Schmitt, V. Koznikov, V. Chignirov, Jpn. J. Appl. Phys. 31 (1992) 2155. ]. But photoalignment methods have an image sticking problem by un-reacted photosensitive functional groups, which can be a severe defect to achieve high reliability of liquid crystal display (LCD) panels. So the un-reacted photosensitive functional groups were deactivated using bromine or ethanethiol. Bromine and ethanethiol lead to the formation of carbon-bromine or carbon-sulfur bonds from carbon-carbon double bonds. The interfacial reaction of bromine or ethanethiol on the polyimide surface has been studied using in situ X-ray photoelectron spectroscopy (XPS). The change of surface tension was observed by using a contact angle analyzer. The photoelastic modulator (PEM) was used to analyze the optical anisotropy on the polyimide surface. Also, the atomic force microscopy (AFM) was used to observe the morphology of polyimide surface [K. Rajesh, M.K. Ram, S.C. Jain, S.B. Samanta, A.V. Narliker, Thin Solid Films 325 (1998) 251.

  17. METABOLISM OF BROMINATED FLAME RETARDANTS IN HUMAN ASTROCYTES AND EFFECTS ON THYROID HORMONE HOMEOSTASIS

    Science.gov (United States)

    In this proposed study, hydroxylated PBDEs and brominated phenols likely will be formed in astrocytes as a result of cytochrome p450-mediated metabolism. Previous studies have shown that polychlorinated biphenyls (PCBs) affect the regulation of thyroid hormones at the bloo...

  18. Bromine release from blowing snow and its impact on tropospheric chemistry

    Science.gov (United States)

    Griffiths, Paul; Yang, Xin; Abraham, N. Luke; Archibald, Alexander; Pyle, John

    2016-04-01

    In the last two decades, significant depletion of boundary layer ozone (ozone depletion events, ODEs) has been observed in both Arctic and Antarctic spring. ODEs are attributed to catalytic destruction by bromine radicals (Br plus BrO), especially during bromine explosion events (BEs), when high concentrations of BrO periodically occur. The source of bromine and the mechanism that sustains the high BrO levels are still the subject of study. Recent work by Pratt et al. (2013) posits Br2 production within saline snow and sea ice which leads to sudden ODEs. Previously, Yang et al. (2008) suggested snow could provide a source of (depleted) sea-salt aerosol if wicked from the surface of ice. They suggest that rapid depletion of bromide from the aerosol will constitute a source of photochemical Bry. Given the large sea ice extent in polar regions, this may constitute a significant source of sea salt and bromine in the polar lower atmosphere. While bromine release from blowing snow is perhaps less likely to trigger sudden ODEs, it may make a contribution to regional scale processes affecting ozone levels. Currently, the model parameterisations of Yang et al. assumes that rapid release of bromine occurs from fresh snow on sea ice during periods of strong wind. The parameterisation depends on an assumed sea-salt aerosol distribution generated via sublimation of the snow above the boundary layer, as well as taking into account the salinity of the snow. In this work, we draw on recent measurements by scientists from the British Antarctic Survey during a cruise aboard the Polarstern in the southern oceans. This has provided an extensive set of measurements of the chemical and physical characteristics of blowing snow over sea ice, and of the aerosol associated with it. Based on the observations, we have developed an improved parameterisation of the release of bromine from blowing snow. The paper presents results from the simulation performed using the United Kingdom Chemistry

  19. Monitoring of WEEE plastics in regards to brominated flame retardants using handheld XRF

    International Nuclear Information System (INIS)

    Highlights: • Specification of an empirical factor for conversion from bromine to PBB and PBDE. • The handheld XRF device was validated for this particular application. • A very large number of over 4600 pieces of monitor housings was analysed. • The recyclable fraction mounts up to 85% for TV but only 53% of PC waste plastics. • A high percentage of pieces with bromine contents of over 50,000 ppm was obtained. - Abstract: This contribution is focused on the on-site determination of the bromine content in waste electrical and electronic equipment (WEEE), in particular waste plastics from television sets (TV) and personal computer monitors (PC) using a handheld X-ray fluorescence (XRF) device. The described approach allows the examination of samples in regards to the compliance with legal specifications for polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) directly after disassembling and facilitates the sorting out of plastics with high contents of brominated flame retardants (BFRs). In all, over 3000 pieces of black (TV) and 1600 pieces of grey (PC) plastic waste were analysed with handheld XRF technique for this study. Especially noticeable was the high percentage of pieces with a bromine content of over 50,000 ppm for TV (7%) and PC (39%) waste plastics. The applied method was validated by comparing the data of handheld XRF with results obtained by GC–MS. The results showed the expected and sufficiently accurate correlation between these two methods. It is shown that handheld XRF technique is an effective tool for fast monitoring of large volumes of WEEE plastics in regards to BFRs for on-site measurements

  20. Monitoring of WEEE plastics in regards to brominated flame retardants using handheld XRF

    Energy Technology Data Exchange (ETDEWEB)

    Aldrian, Alexia, E-mail: alexia.aldrian@unileoben.ac.at [Chair of Waste Processing Technology and Waste Management, Montanuniversitaet Leoben, Franz-Josef-Straße 18, 8700 Leoben (Austria); Ledersteger, Alfred, E-mail: a.ledersteger@saubermacher.at [Saubermacher Dienstleistungs AG, Hans-Roth-Straße 1, 8073 Feldkirchen bei Graz (Austria); Pomberger, Roland, E-mail: roland.pomberger@unileoben.ac.at [Chair of Waste Processing Technology and Waste Management, Montanuniversitaet Leoben, Franz-Josef-Straße 18, 8700 Leoben (Austria)

    2015-02-15

    Highlights: • Specification of an empirical factor for conversion from bromine to PBB and PBDE. • The handheld XRF device was validated for this particular application. • A very large number of over 4600 pieces of monitor housings was analysed. • The recyclable fraction mounts up to 85% for TV but only 53% of PC waste plastics. • A high percentage of pieces with bromine contents of over 50,000 ppm was obtained. - Abstract: This contribution is focused on the on-site determination of the bromine content in waste electrical and electronic equipment (WEEE), in particular waste plastics from television sets (TV) and personal computer monitors (PC) using a handheld X-ray fluorescence (XRF) device. The described approach allows the examination of samples in regards to the compliance with legal specifications for polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) directly after disassembling and facilitates the sorting out of plastics with high contents of brominated flame retardants (BFRs). In all, over 3000 pieces of black (TV) and 1600 pieces of grey (PC) plastic waste were analysed with handheld XRF technique for this study. Especially noticeable was the high percentage of pieces with a bromine content of over 50,000 ppm for TV (7%) and PC (39%) waste plastics. The applied method was validated by comparing the data of handheld XRF with results obtained by GC–MS. The results showed the expected and sufficiently accurate correlation between these two methods. It is shown that handheld XRF technique is an effective tool for fast monitoring of large volumes of WEEE plastics in regards to BFRs for on-site measurements.

  1. Interactions of bromine, chlorine, and iodine photochemistry during ozone depletions in Barrow, Alaska

    Directory of Open Access Journals (Sweden)

    C. R. Thompson

    2014-11-01

    Full Text Available The springtime depletion of tropospheric ozone in the Arctic is known to be caused by active halogen photochemistry resulting from halogen atom precursors emitted from snow, ice, or aerosol surfaces. The role of bromine in driving ozone depletion events (ODEs has been generally accepted, but much less is known about the role of chlorine radicals in ozone depletion chemistry. While the potential impact of iodine in the High Arctic is more uncertain, there have been indications of active iodine chemistry through observed enhancements in filterable iodide, probable detection of tropospheric IO, and recently, detection of atmospheric I2. Despite decades of research, significant uncertainty remains regarding the chemical mechanisms associated with the bromine-catalyzed depletion of ozone, as well as the complex interactions that occur in the polar boundary layer due to halogen chemistry. To investigate this, we developed a zero-dimensional photochemical model, constrained with measurements from the 2009 OASIS field campaign in Barrow, Alaska. We simulated a 7 day period during late March that included a full ozone depletion event lasting 3 days and subsequent ozone recovery to study the interactions of halogen radicals under these different conditions. In addition, the effects of iodine added to our base model were investigated. While bromine atoms were primarily responsible for ODEs, chlorine and iodine were found to enhance the depletion rates and iodine was found to be more efficient per atom at depleting ozone than Br. The interaction between chlorine and bromine is complex, as the presence of chlorine can increase the recycling and production of Br atoms, while also increasing reactive bromine sinks under certain conditions. Chlorine chemistry was also found to have significant impacts on both HO2 and RO2. The results of this work highlight the need for future studies on the production mechanisms of Br2 and Cl2, as well as on the potential

  2. Interactions of bromine, chlorine, and iodine photochemistry during ozone depletions in Barrow, Alaska

    Science.gov (United States)

    Thompson, C. R.; Shepson, P. B.; Liao, J.; Huey, L. G.; Apel, E. C.; Cantrell, C. A.; Flocke, F.; Orlando, J.; Fried, A.; Hall, S. R.; Hornbrook, R. S.; Knapp, D. J.; Mauldin, R. L., III; Montzka, D. D.; Sive, B. C.; Ullmann, K.; Weibring, P.; Weinheimer, A.

    2015-08-01

    The springtime depletion of tropospheric ozone in the Arctic is known to be caused by active halogen photochemistry resulting from halogen atom precursors emitted from snow, ice, or aerosol surfaces. The role of bromine in driving ozone depletion events (ODEs) has been generally accepted, but much less is known about the role of chlorine radicals in ozone depletion chemistry. While the potential impact of iodine in the High Arctic is more uncertain, there have been indications of active iodine chemistry through observed enhancements in filterable iodide, probable detection of tropospheric IO, and recently, observation of snowpack photochemical production of I2. Despite decades of research, significant uncertainty remains regarding the chemical mechanisms associated with the bromine-catalyzed depletion of ozone, as well as the complex interactions that occur in the polar boundary layer due to halogen chemistry. To investigate this, we developed a zero-dimensional photochemical model, constrained with measurements from the 2009 OASIS field campaign in Barrow, Alaska. We simulated a 7-day period during late March that included a full ozone depletion event lasting 3 days and subsequent ozone recovery to study the interactions of halogen radicals under these different conditions. In addition, the effects of iodine added to our Base Model were investigated. While bromine atoms were primarily responsible for ODEs, chlorine and iodine were found to enhance the depletion rates and iodine was found to be more efficient per atom at depleting ozone than Br. The interaction between chlorine and bromine is complex, as the presence of chlorine can increase the recycling and production of Br atoms, while also increasing reactive bromine sinks under certain conditions. Chlorine chemistry was also found to have significant impacts on both HO2 and RO2, with organic compounds serving as the primary reaction partner for Cl atoms. The results of this work highlight the need for future

  3. A case study of a transported bromine explosion event in the Canadian high arctic

    Science.gov (United States)

    Zhao, X.; Strong, K.; Adams, C.; Schofield, R.; Yang, X.; Richter, A.; Friess, U.; Blechschmidt, A.-M.; Koo, J.-H.

    2016-01-01

    Ozone depletion events in the polar troposphere have been linked to extremely high concentrations of bromine, known as bromine explosion events (BEE). However, the optimum meteorological conditions for the occurrence of these events remain uncertain. On 4-5 April 2011, a combination of both blowing snow and a stable shallow boundary layer was observed during a BEE at Eureka, Canada (86.4°W, 80.1°N). Measurements made by a Multi-Axis Differential Optical Absorption Spectroscopy spectrometer were used to retrieve BrO profiles and partial columns. During this event, the near-surface BrO volume mixing ratio increased to ~20 parts per trillion by volume, while ozone was depleted to ~1 ppbv from the surface to 700 m. Back trajectories and Global Ozone Monitoring Experiment-2 satellite tropospheric BrO columns confirmed that this event originated from a bromine explosion over the Beaufort Sea. From 30 to 31 March, meteorological data showed high wind speeds (24 m/s) and elevated boundary layer heights (~800 m) over the Beaufort Sea. Long-distance transportation (~1800 km over 5 days) to Eureka indicated strong recycling of BrO within the bromine plume. This event was generally captured by a global chemistry-climate model when a sea-salt bromine source from blowing snow was included. A model sensitivity study indicated that the surface BrO at Eureka was controlled by both local photochemistry and boundary layer dynamics. Comparison of the model results with both ground-based and satellite measurements confirmed that the BEE observed at Eureka was triggered by transport of enhanced BrO from the Beaufort Sea followed by local production/recycling under stable atmospheric shallow boundary layer conditions.

  4. Global atmospheric model for mercury including oxidation by bromine atoms

    Directory of Open Access Journals (Sweden)

    C. D. Holmes

    2010-12-01

    Full Text Available Global models of atmospheric mercury generally assume that gas-phase OH and ozone are the main oxidants converting Hg0 to HgII and thus driving mercury deposition to ecosystems. However, thermodynamic considerations argue against the importance of these reactions. We demonstrate here the viability of atomic bromine (Br as an alternative Hg0 oxidant. We conduct a global 3-D simulation with the GEOS-Chem model assuming gas-phase Br to be the sole Hg0 oxidant (Hg + Br model and compare to the previous version of the model with OH and ozone as the sole oxidants (Hg + OH/O3 model. We specify global 3-D Br concentration fields based on our best understanding of tropospheric and stratospheric Br chemistry. In both the Hg + Br and Hg + OH/O3 models, we add an aqueous photochemical reduction of HgII in cloud to impose a tropospheric lifetime for mercury of 6.5 months against deposition, as needed to reconcile observed total gaseous mercury (TGM concentrations with current estimates of anthropogenic emissions. This added reduction would not be necessary in the Hg + Br model if we adjusted the Br oxidation kinetics downward within their range of uncertainty. We find that the Hg + Br and Hg + OH/O3 models are equally capable of reproducing the spatial distribution of TGM and its seasonal cycle at northern mid-latitudes. The Hg + Br model shows a steeper decline of TGM concentrations from the tropics to southern mid-latitudes. Only the Hg + Br model can reproduce the springtime depletion and summer rebound of TGM observed at polar sites; the snowpack component of GEOS-Chem suggests that 40% of HgII deposited to snow in the Arctic is transferred to the ocean and land reservoirs, amounting to a net deposition flux to the Arctic of 60 Mg a−1. Summertime events of depleted Hg0 at Antarctic sites due to subsidence are much better simulated by

  5. CYP79F1 and CYP79F2 have distinct functions in the biosynthesis of aliphatic glucosinolates in Arabidopsis.

    Science.gov (United States)

    Chen, Sixue; Glawischnig, Erich; Jørgensen, Kirsten; Naur, Peter; Jørgensen, Bodil; Olsen, Carl-Erik; Hansen, Carsten H; Rasmussen, Hasse; Pickett, John A; Halkier, Barbara A

    2003-03-01

    Cytochromes P450 of the CYP79 family catalyze the conversion of amino acids to oximes in the biosynthesis of glucosinolates, a group of natural plant products known to be involved in plant defense and as a source of flavor compounds, cancer-preventing agents and bioherbicides. We report a detailed biochemical analysis of the substrate specificity and kinetics of CYP79F1 and CYP79F2, two cytochromes P450 involved in the biosynthesis of aliphatic glucosinolates in Arabidopsis thaliana. Using recombinant CYP79F1 and CYP79F2 expressed in Escherichia coli and Saccharomyces cerevisiae, respectively, we show that CYP79F1 metabolizes mono- to hexahomomethionine, resulting in both short- and long-chain aliphatic glucosinolates. In contrast, CYP79F2 exclusively metabolizes long-chain elongated penta- and hexahomomethionines. CYP79F1 and CYP79F2 are spatially and developmentally regulated, with different gene expression patterns. CYP79F2 is highly expressed in hypocotyl and roots, whereas CYP79F1 is strongly expressed in cotyledons, rosette leaves, stems, and siliques. A transposon-tagged CYP79F1 knockout mutant completely lacks short-chain aliphatic glucosinolates, but has an increased level of long-chain aliphatic glucosinolates, especially in leaves and seeds. The level of long-chain aliphatic glucosinolates in a transposon-tagged CYP79F2 knockout mutant is substantially reduced, whereas the level of short-chain aliphatic glucosinolates is not affected. Biochemical characterization of CYP79F1 and CYP79F2, and gene expression analysis, combined with glucosinolate profiling of knockout mutants demonstrate the functional role of these enzymes. This provides valuable insights into the metabolic network leading to the biosynthesis of aliphatic glucosinolates, and into metabolic engineering of altered aliphatic glucosinolate profiles to improve nutritional value and pest resistance. PMID:12609033

  6. The effect of bromination of carbon fibers on the coefficient of thermal expansion of graphite fiber-epoxy composites

    Science.gov (United States)

    Jaworske, D. A.; Maciag, C.

    1987-01-01

    To examine the effect of bromination of carbon fibers on the coefficient of thermal expansion (CTE) of carbon fiber epoxy composites, several pristine and brominated carbon fiber-epoxy composite samples were subjected to thermomechanical analysis. The CTE's of these samples were measured in the uniaxial and transverse directions. The CTE was dominated by the fibers in the uniaxial direction, while it was dominated by the matrix in the transverse directions. Bromination had no effect on the CTE of any of the composites. In addition, the CTE of fiber tow was measured in the absence of a polymer matrix, using an extension probe. The results from this technique were inconclusive.

  7. Three-quasiparticle excitations in 79Kr

    International Nuclear Information System (INIS)

    Excited states in 79Kr have been investigated up to spin 27/2 using techniques of in-beam γ-ray spectroscopy. Mean lifetimes of 33 levels have been determined applying Doppler-shift and γ-RF methods. The bands built on the g9/2, [303]5/2, [301]1/2 and [301]3/2 neutron configurations have been interpreted in terms of the cranking model. The g9/2 band is a rotation-aligned band. The band crossing at spin 21/2 is attributed to the alignment of a pair of g9/2 protons. The 3qp band above the second 21+/2 state includes M1 transitions with high transition rates up to 0.6 W.u. The negative-parity bands show a regular structure at low spins. Irregularities in these bands above spin 15/2 are interpreted as due to the alignment of two g9/2 protons as well. A ΔI=1 sequence starting at a (17-/2) state includes M1 transitions of rates of about 0.3 W.u. This structure has been proposed to involve a non-collective 3qp excitation with two g9/2 nucleons. Deformed-shell-model cranking calculations with the Woods-Saxon potential predict the coexistence of prolate and oblate shapes at low spin due to the polarization of the core by the valence neutron, and a change towards prolate shapes after the alignment of two g9/2 protons. (orig.)

  8. Combustion and inorganic bromine emission of waste printed circuit boards in a high temperature furnace

    International Nuclear Information System (INIS)

    Highlights: ► The combustion efficiency of waste printed circuit boards (PCBs) depends on temperature, excess air factor, and high temperature zone residence time. Temperature has the most significant impact. Under the proposed condition, combustion of waste PCBs alone is quite complete within the furnace. ► High temperature prompts a more complete bromine release and conversion. When temperature is high enough, 99.9% organobrominated compounds, the potential precursors for brominated dixoins formation, are destroyed efficiently and convert to inorganic bromine in flue gas, as HBr and Br2. ► Temperature has crucial influence over the inhibition of HBr conversion to Br2, while the oxygen partial pressure plays a reverse role in the conversion to a very small extent. Increasing temperature will decrease the volume percentage ratio of Br2/HBr in flue gas greatly. ► The thermodynamic equilibrium approach of bromine conversion was investigated. The two forms of inorganic bromine in flue gas substantially reach thermodynamic equilibrium within 0.25 s. Under the proposed operating condition, the reaction of Br transfer and conversion finish. - Abstract: High temperature combustion experiments of waste printed circuit boards (PCBs) were conducted using a lab-scale system featuring a continuously-fed drop tube furnace. Combustion efficiency and the occurrence of inorganic bromine (HBr and Br2) were systematically studied by monitoring the main combustion products continuously. The influence of furnace temperature (T) was studied from 800 to 1400 °C, the excess air factor (EAF) was varied from 1.2 to 1.9 and the residence time in the high temperature zone (RTHT) was set at 0.25, 0.5, or 0.75 s. Combustion efficiency depends on temperature, EAF and RTHT; temperature has the most significant effect. Conversion of organic bromine from flame retardants into HBr and Br2 depends on temperature and EAF. Temperature has crucial influence over the ratio of HBr to Br2

  9. Distribution of brominated compounds within the sponge Aplysina aerophoba: coupling of X-ray microanalysis with cryofixation techniques.

    Science.gov (United States)

    Turon, X; Becerro, M A; Uriz, M J

    2000-08-01

    The major secondary metabolites of the sponge Aplysina aerophoba are brominated compounds. X-ray energy dispersive microanalysis was therefore used to locate secondary metabolites via the Br signal in energy emission spectra from sponge sections. To test the reliability of this method in the face of the loss or redistribution of metabolites during processing, we compared the results obtained by conventional aldehyde fixation with those obtained by cryofixation and cryosubstitution with and without cryoembedding. Bromine appeared to be concentrated in two sponge structures, viz. fibres and spherulous cells, when cryofixed material was examined. However, X-ray microanalysis failed to demonstrate the presence of bromine in spherulous cells in chemically fixed samples, showing the need for cryotechniques to avoid the loss of compounds. Cryofixation plus cryosubstitution methods performed best regarding structural preservation and the immobilization of metabolites. The presence of bromine in the spherulous cells suggests that this cell type is the producer of the secondary metabolites, as described for other sponge species. Nevertheless, the presence of bromine in sponge fibres indicates that they can accumulate metabolic substances, although we have been unable to assess whether the chemicals are in their original form or in a modified state within the fibres. A. aerophoba has both bacterial and cyanobacterial symbionts in its mesohyl; the absence of brominated compounds in them contrasts with previous findings in other sponges with prokaryote symbionts. PMID:10955726

  10. Molten-Phase Hydrolysis Stage Analysis and Experiments for the Calcium Bromine Thermochemical Cycle

    International Nuclear Information System (INIS)

    The goal of the United States Department of Energy Nuclear Hydrogen Initiative as linked with the Generation IV Nuclear Energy Systems Initiative for Gas Reactor Deployment is to develop a cost-effective, proliferation-resistant, low-greenhouse-gas emissions, and sustainable, nuclear-based energy supply system. The calcium-bromine cycle under development at Argonne National Laboratory combines both experimental and modeling studies of a novel continuous 'hybrid' cycle for hydrogen production, where 'hybrid' means that both nuclear heat and electricity are employed. Engineering the calcium-bromine cycle for continuous operation should facilitate its practical development since there will be an inherent advantage to using components and materials which will operate in a constant, non-cycling chemical and thermal environment. This paper focuses on the first and important calcium bromide hydrolysis stage to generate hydrogen bromide, which when split by electrolysis, produces hydrogen. (authors)

  11. Co-doping of Potassium and Bromine in Carbon Nanotubes: A Density Functional Theory Study

    Institute of Scientific and Technical Information of China (English)

    XIAO Yong; YAN xiao-Hong; DING Jian-Wen

    2007-01-01

    We investigate the co-doping of potassium and bromine in singlewalled carbon nanotubes (SWCNTs)and doublewalled carbon nanotubes(DWCNTs)based on density functional theory.In the co-doped(6,O)SWCNTs,the 4s electron of potassium is transferred to nanotube and Br,leading to the n-type feature of SWCNTs.When potassium is intercalated into inner tube and bromine is put on outer tube,the positive and negative charges reside on the outer and inner tubes of the(7.0)@(16,0)DWCNT,respectively.It is expected that DWCNTs would be an ideal candidate for p-n junction and diode applications.

  12. Stratospheric ozone depletion and future levels of atmospheric chlorine and bromine

    Science.gov (United States)

    Prather, Michael J.; Watson, Robert T.

    1990-01-01

    The rise in atmospheric chlorine levels caused by the emission of chlorofluorocarbons and other halocarbons is thought to be the main cause of the appearance of the Antarctic ozone 'hole' in the late 1970s, and the more modest ozone depletion observed over parts of the Northern Hemisphere. Atmospheric bromine, also associated with halocarbon emissions, is believed to contribute to ozone depletion. Over the next decade, further increases in these compounds are inevitable. Model calculations show that by the end of the next century, atmospheric chlorine and bromine levels may return to those prevalent before the onset of the ozone hole, but only if more stringent regulations are applied to halocarbon production than those currently proposed.

  13. First measurements of total chlorine and bromine in the lower stratosphere

    International Nuclear Information System (INIS)

    A total halogen collection system employing ultra-pure activated charcoal traps has been developed for use in the stratosphere aboard aircraft and balloon sampling platforms. Neutron activation techniques for low-level chlorine, bromine, and iodine analysis within the activated charcoal sampling matrix were developed. Initial results from six aircraft flights and one balloon mission in the lower stratosphere are presented for latitudes ranging from 160N to 670N. Little variability was observed in twelve total, gaseous and particulate chlorine (Cl/sub tot/) determinations as a function of latitude at 20 km with values ranging between 2.7 +- 9 ppbV and 3.2 +- .7 ppbV. Five total bromine (Br/sub tot/) values showed substantial variability ranging from 7 +- 4 pptV to 40 +- 11 pptV. No iodine was observed in any samples but a calculated I/sub tot/ upper limit of < 3 pptV was determined

  14. Occupational exposure to brominated flame retardants : With emphasis on polybrominated diphenyl ethers

    OpenAIRE

    Thuresson, Kaj

    2004-01-01

    Brominated flame retardants (BFRs) are a diverse group of chemicals, which are used to slow down or inhibit the development of fires. BFRs are incorporated into a wide range of consumer products that are considered as potential fire hazards, such as TV-sets, household appliances, computers, and textiles. The production and use of BFRs is extensive and consists of mainly tetrabromobisphenol A (TBBPA), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecan (HBCD). BFRs in general, but...

  15. Assessing oestrogenic effects of brominated flame retardants Hexabromocyclododecane and Tetrabromobisphenol A on MCF-7 cells

    Czech Academy of Sciences Publication Activity Database

    Dorosh, Andriy; Děd, Lukáš; Elzeinová, Fatima; Pěknicová, Jana

    2010-01-01

    Roč. 56, - (2010), s. 35-39. ISSN 0015-5500 R&D Projects: GA MŠk(CZ) 1M06011; GA MŠk(CZ) 2B06151 Institutional research plan: CEZ:AV0Z50520701 Keywords : endocrine disruptors * BRF - brominated flame retardant * MCF-7 cells * TFF1 - trefoil factor Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 0.729, year: 2010

  16. Brominated Skeletal Components of the Marine Demosponges, Aplysina cavernicola and Ianthella basta: Analytical and Biochemical Investigations

    OpenAIRE

    Eike Brunner; Peter Proksch; Hermann Ehrlich; Renate Schulze; Susanne Ueberlein; Hendrik Niemann; Kurt Kunze; Karl-Heinz van Pée

    2013-01-01

    Demosponges possess a skeleton made of a composite material with various organic constituents and/or siliceous spicules. Chitin is an integral part of the skeleton of different sponges of the order Verongida. Moreover, sponges of the order Verongida, such as Aplysina cavernicola or Ianthella basta, are well-known for the biosynthesis of brominated tyrosine derivates, characteristic bioactive natural products. It has been unknown so far whether these compounds are exclusively present in the ce...

  17. Reductive Dehalogenation of Brominated Phenolic Compounds by Microorganisms Associated with the Marine Sponge Aplysina aerophoba

    OpenAIRE

    Ahn, Young-Beom; Rhee, Sung-Keun; Fennell, Donna E.; Kerkhof, Lee J.; Hentschel, Ute; Häggblom, Max M.

    2003-01-01

    Marine sponges are natural sources of brominated organic compounds, including bromoindoles, bromophenols, and bromopyrroles, that may comprise up to 12% of the sponge dry weight. Aplysina aerophoba sponges harbor large numbers of bacteria that can amount to 40% of the biomass of the animal. We postulated that there might be mechanisms for microbially mediated degradation of these halogenated chemicals within the sponges. The capability of anaerobic microorganisms associated with the marine sp...

  18. Ship-source pollution by polychlorinated biphenyls and brominated flame retardants

    OpenAIRE

    ČULIN, Jelena; Bielić, Toni

    2015-01-01

    Polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) are groups of anthropogenic contaminants that have been routinely used in many applications for several decades. Prior to the discovery of their detrimental health effects and subsequent implementation of regulatory measures they were widely applied in shipbuilding. They are still found onboard active and inactive ships and pose a risk to human and environment. Therefore, it is important to continue to carry out preven...

  19. Tropospheric bromine chemistry: implications for present and pre-industrial ozone and mercury

    Directory of Open Access Journals (Sweden)

    J. P. Parrella

    2012-04-01

    Full Text Available We present a new model for the global tropospheric chemistry of inorganic bromine (Bry coupled to oxidant-aerosol chemistry in the GEOS-Chem chemical transport model (CTM. Sources of tropospheric Bry include debromination of sea-salt aerosol, photolysis and oxidation of short-lived bromocarbons, and transport from the stratosphere. Comparison to a GOME-2 satellite climatology of tropospheric BrO columns shows that the model can reproduce the observed increase of BrO with latitude, the northern mid-latitudes maximum in winter, and the Arctic maximum in spring. This successful simulation is contingent on the HOBr + HBr reaction taking place in aqueous aerosols and ice clouds. Bromine chemistry in the model decreases tropospheric ozone concentrations by <1−8 nmol mol−1 (6.5% globally, with the largest effects in the northern extratropics in spring. The global mean tropospheric OH concentration decreases by 4%. Inclusion of bromine chemistry improves the ability of global models (GEOS-Chem and p-TOMCAT to simulate observed 19th-century ozone and its seasonality. Bromine effects on tropospheric ozone are comparable in the present-day and pre-industrial atmospheres so that estimates of anthropogenic radiative forcing are minimally affected. Br atom concentrations are 40% higher in the pre-industrial atmosphere due to lower ozone, which would decrease by a factor of 2 the atmospheric lifetime of elemental mercury against oxidation by Br. This suggests that historical anthropogenic mercury emissions may have mostly deposited to northern mid-latitudes, enriching the corresponding surface reservoirs. The persistent rise in background surface ozone at northern mid-latitudes during the past decades could possibly contribute to the observations of elevated mercury in subsurface waters of the North Atlantic.

  20. Tropospheric bromine chemistry: implications for present and pre-industrial ozone and mercury

    Directory of Open Access Journals (Sweden)

    J. P. Parrella

    2012-08-01

    Full Text Available We present a new model for the global tropospheric chemistry of inorganic bromine (Bry coupled to oxidant-aerosol chemistry in the GEOS-Chem chemical transport model (CTM. Sources of tropospheric Bry include debromination of sea-salt aerosol, photolysis and oxidation of short-lived bromocarbons, and transport from the stratosphere. Comparison to a GOME-2 satellite climatology of tropospheric BrO columns shows that the model can reproduce the observed increase of BrO with latitude, the northern mid-latitudes maximum in winter, and the Arctic maximum in spring. This successful simulation is contingent on the HOBr + HBr reaction taking place in aqueous aerosols and ice clouds. Bromine chemistry in the model decreases tropospheric ozone mixing ratios by <1–8 nmol mol−1 (6.5% globally, with the largest effects in the northern extratropics in spring. The global mean tropospheric OH concentration decreases by 4%. Inclusion of bromine chemistry improves the ability of global models (GEOS-Chem and p-TOMCAT to simulate observed 19th-century ozone and its seasonality. Bromine effects on tropospheric ozone are comparable in the present-day and pre-industrial atmospheres so that estimates of anthropogenic radiative forcing are minimally affected. Br atom concentrations are 40% higher in the pre-industrial atmosphere due to lower ozone, which would decrease by a factor of 2 the atmospheric lifetime of elemental mercury against oxidation by Br. This suggests that historical anthropogenic mercury emissions may have mostly deposited to northern mid-latitudes, enriching the corresponding surface reservoirs. The persistent rise in background surface ozone at northern mid-latitudes during the past decades could possibly contribute to the observations of elevated mercury in subsurface waters of the North Atlantic.

  1. A comparison of the virucidal properties of chlorine, chlorine dioxide, bromine chloride and iodine.

    OpenAIRE

    Taylor, G R; Butler, M

    1982-01-01

    Chlorine dioxide, bromine chloride and iodine were compared with chlorine as virucidal agents. Under optimal conditions all disinfectants were effective at low concentrations, but each disinfectant responded differently to acidity and alkalinity. Disinfection by chlorine was impaired by the presence of ammonia, but the other disinfectants retained much of their potency. Disinfection of poliovirus by iodine resulted in structural changes in the virions as seen by electron micrroscopy, but the ...

  2. Bromine monoxide / sulphur dioxide ratios in relation to volcanological observations at Mt. Etna 2006–2009

    OpenAIRE

    N. Bobrowski; Giuffrida, G

    2012-01-01

    Over a 3-yr period, from 2006 to 2009, frequent scattered sunlight DOAS measurements were conducted at Mt. Etna at a distance of around 6 km downwind from the summit craters. During the same period and in addition to these measurements, volcanic observations were made by regularly visiting various parts of Mt. Etna. Here, results from these measurements and observations are presented and their relation is discussed. The focus of the investigation is the bromine monoxide/sulphur dioxide (BrO ...

  3. Mercury oxidation from bromine chemistry in the free troposphere over the southeastern US

    OpenAIRE

    S. Coburn; Dix, B.; Edgerton, E.; Holmes, C. D; Kinnison, D.; Liang, Q; A. ter Schure; Wang, S.; R. Volkamer

    2015-01-01

    The elevated deposition of atmospheric mercury over the Southeastern United States is currently not well understood. Here we measure partial columns and vertical profiles of bromine monoxide (BrO) radicals, a key component of mercury oxidation chemistry, to better understand the processes and altitudes at which mercury is being oxidized in the atmosphere. We use the data from a ground-based MAX-DOAS instrument located at a coastal site ~ 1 km from the Gulf o...

  4. Toxicity of brominated flame retardants with focus on retinoid system disturbances

    OpenAIRE

    Litens Karlsson, Sabina

    2015-01-01

    Background: Brominated flame retardants (BFR) are detected in the environment and biota all over the world. They contribute to the human body burden of industrial chemicals and exposure is mainly via food. Indoor dust contributes substantially in some exposure situations, which involve small children. Regulatory restrictions and bans have been introduced as some BFRs can impact proper development, potentially via the endocrine system. Objectives: The study aim was to clarify the role of...

  5. Volcanic plumes: Evaluation of spectroscopic measurements, early detection, and bromine chemistry

    OpenAIRE

    Vogel, Leif

    2011-01-01

    Volcanos emit inter alia highly reactive chemical compounds, which influence the atmosphere on a local, regional and global scale. Subject of this study are measurements of volcanic plumes via differential optical absorption spectroscopy (DOAS). A new tool for analysis and optimisation of evaluation schemes was developed, which is applicable to any DOAS measurement. Measurements of bromine monoxide (BrO) and sulphur dioxide (SO2 ) are presented, which were gathered at Mt. Etna (Italy) and Pac...

  6. Thermal Recycling of Brominated Flame Retardants with Fe2O3.

    Science.gov (United States)

    Altarawneh, Mohammednoor; Ahmed, Oday H; Jiang, Zhong-Tao; Dlugogorski, Bogdan Z

    2016-08-01

    Plastics containing brominated flame retardants (BFRs) constitute the major fraction of nonmetallic content in e-waste. Co-pyrolysis of BFRs with hematite (Fe2O3) represents a viable option for the thermal recycling of BFRs. Consensus of experimental findings confirms the excellent bromine fixation ability of Fe2O3 and the subsequent formation of iron bromides. This contribution provides a comprehensive mechanistic account of the primary reactions between a cluster model of Fe2O3 and major bromine-bearing products from the decomposition of tetrabromobisphenol A (TBBA), the most commonly deployed BFR. We estimate the thermo-kinetic parameters for interactions of Fe2O3 with HBr, brominated alkanes and alkenes, bromobenzene, and bromophenol. Dissociative addition of HBr at a Fe-O bond proceeds through a trivial barrier of 8.2 kcal/mol with fitted parameters in the Arrhenius equation of k(T) = 7.96 × 10(11) exp(-6400/RT) s(-1). The facile and irreversible nature for HBr addition to Fe2O3 accords with the experimentally reported 90% reduction in HBr emission when Fe2O3 interacts with TBBA pyrolysates. A detailed kinetic analysis indicates that, transformation of Fe2O3 into iron bromides and oxybromides occurs via successive addition of HBr to Fe(Br)-O(H) entities. Elimination of a water molecule proceeds through an intramolecular H transfer. A direct elimination one-step mechanism operates in the dehydrohalogenation of bromoethane into ethene over Fe2O3. Dissociative decomposition and direct elimination channels assume comparable reaction rates in formation of acetylene from vinyl bromide. Results from this study provide an atomic-based insight into a promising thermal recycling route of e-waste. PMID:27366936

  7. Brominated Biphenyls Prime Extensive Microbial Reductive Dehalogenation of Aroclor 1260 in Housatonic River Sediment

    OpenAIRE

    Bedard, Donna L.; Van Dort, Heidi; DeWeerd, Kim A.

    1998-01-01

    The upper Housatonic River and Woods Pond (Lenox, Mass.), a shallow impoundment on the river, are contaminated with polychlorinated biphenyls (PCBs), the residue of partially dechlorinated Aroclor 1260. Certain PCB congeners have the ability to activate or “prime” anaerobic microorganisms in Woods Pond sediment to reductively dehalogenate the Aroclor 1260 residue. We proposed that brominated biphenyls might have the same effect and tested the priming activities of 14 mono-, di-, and tribromin...

  8. The bromination Hypocrellin A and the spectra character of the reaction of gelatin with the derivative

    International Nuclear Information System (INIS)

    The bromination derivates of hypocrellin A (Br-HA) was prepared in this paper, and the photodynamic activity also was appraised. UV-Vis spectroscopy and Fluorescence spectrophotometer were employed to detect the reaction of Br-HA with gelatin. The result shown the Br-HA can react with gelatin, and the HA-Br also photodegraded the pyridinoline cross-link formation in gelatin.

  9. Reactive airways dysfunction and systemic complaints after mass exposure to bromine.

    OpenAIRE

    Woolf, A; Shannon, M.

    1999-01-01

    Occasionally children are the victims of mass poisoning from an environmental contaminant that occurs due to an unexpected common point source of exposure. In many cases the contaminant is a widely used chemical generally considered to be safe. In the following case, members of a sports team visiting a community for an athletic event were exposed to chemicals while staying at a local motel. Bromine-based sanitizing agents and other chemicals such as hydrochloric acid, which were used in exces...

  10. On bromine, nitrogen oxides and ozone depletion in the tropospheric plume of Erebus volcano (Antarctica)

    OpenAIRE

    Boichu, Marie; Oppenheimer, Clive; Roberts, Tjarda J.; V. I. Tsanev; Kyle, Philip R

    2011-01-01

    International audience Since the discovery of bromine oxide (BrO) in volcanic emissions, there has been speculation concerning its role in chemical evolution and notably ozone depletion in volcanic plumes. We report the first measurements using Differential Optical Absorption Spectroscopy (DOAS) of BrO in the tropospheric plume of the persistently degassing Erebus volcano (Antarctica). These are the first observations pertaining to emissions from an alkaline phonolitic magma. The observed ...

  11. Interactions of bromine, chlorine, and iodine photochemistry during ozone depletions in Barrow, Alaska

    OpenAIRE

    Thompson, C. R.; P. B. Shepson; Liao, J.; Huey, L.G.; E. C. Apel; Cantrell, C. A.; Flocke, F.; Orlando, J.; Fried, A.; Hall, S. R; R. S. Hornbrook; D. J. Knapp; Mauldin III, R. L; Montzka, D. D.; B. C. Sive

    2014-01-01

    The springtime depletion of tropospheric ozone in the Arctic is known to be caused by active halogen photochemistry resulting from halogen atom precursors emitted from snow, ice, or aerosol surfaces. The role of bromine in driving ozone depletion events (ODEs) has been generally accepted, but much less is known about the role of chlorine radicals in ozone depletion chemistry. While the potential impact of iodine in the High Arctic is more uncertain, there ha...

  12. Interactions of bromine, chlorine, and iodine photochemistry during ozone depletions in Barrow, Alaska

    OpenAIRE

    Thompson, C. R.; P. B. Shepson; Liao, J.; Huey, L.G.; E. C. Apel; Cantrell, C. A.; Flocke, F.; Orlando, J.; Fried, A.; Hall, S. R; R. S. Hornbrook; D. J. Knapp; Mauldin III, R. L; Montzka, D. D.; B. C. Sive

    2015-01-01

    The springtime depletion of tropospheric ozone in the Arctic is known to be caused by active halogen photochemistry resulting from halogen atom precursors emitted from snow, ice, or aerosol surfaces. The role of bromine in driving ozone depletion events (ODEs) has been generally accepted, but much less is known about the role of chlorine radicals in ozone depletion chemistry. While the potential impact of iodine in the High Arctic is more uncertain, there have been indicatio...

  13. Brominated and organophosphate flame retardants in selected consumer products on the Japanese market in 2008

    International Nuclear Information System (INIS)

    Highlights: → We examined the flame retardants in electronics, curtains, wallpaper and insulator. → Use of alternative brominated and organophosphate flame retardants was suggested. → All the products investigated also contained PBDEs, TBBPA and polybromophenols. → Incorporation of recycled materials containing hazardous substance was suggested. - Abstract: The concentrations of traditional brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs) in new consumer products, including electronic equipment, curtains, wallpaper, and building materials, on the Japanese market in 2008 were investigated. Although some components of the electronic equipment contained bromine at concentrations on the order of percent by weight, as indicated by X-ray fluorescence analysis, the bromine content could not be fully accounted for by the BFRs analyzed in this study, which included polybrominated diphenylethers, decabromodiphenyl ethane, tetrabromobisphenol A, polybromophenols, and hexabromocyclododecanes. These results suggest the use of alternative BFRs such as newly developed formulations derived from tribromophenol, tetrabromobisphenol A, or both. Among the 11 OPFRs analyzed, triphenylphosphate was present at the highest concentrations in all the products investigated, which suggests the use of condensed-type OPFRs as alternative flame retardants, because they contain triphenylphosphate as an impurity. Tripropylphosphate was not detected in any samples; and trimethylphosphate, tributyl tris(2-butoxyethyl)phosphate, and tris(1,3-dichloro-2-propyl)phosphate were detected in only some components and at low concentrations. Note that all the consumer products evaluated in this study also contained traditional BFRs in amounts that were inadequate to impart flame retardancy, which implies the incorporation of recycled plastic materials containing BFRs that are of global concern.

  14. Simultaneous determination of bromine and iodine in the rat thyroid by short-term INAA

    Czech Academy of Sciences Publication Activity Database

    Pavelka, Stanislav; Vobecký, Miloslav; Babický, Arnošt

    Tokyo: Tokyo Metropolitan University, 2007. s. 118-118. [International Conference on Modern Trends in Activation Analysis /12./. 16.09.2007-21.09.2007, Hachioji] R&D Projects: GA AV ČR(CZ) KJB401630701 Institutional research plan: CEZ:AV0Z50110509; CEZ:AV0Z40310501 Keywords : spo2 * bromine * iodine * thyroid gland Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition

  15. Detailed modeling of the atmospheric degradation mechanism of very-short lived brominated species

    OpenAIRE

    G. Krysztofiak; Catoire, Valéry; Poulet, G.; Marécal, V.; Pirre, Michel; Louis, F.; Canneaux, S.; B. Josse

    2012-01-01

    International audience Detailed chemical reaction schemes for the atmospheric degradations of the very short-lived species (VSLS) bromoform (CHBr3) and dibromomethane (CH2Br2) have been established. These degradation schemes have been implemented in the meteorological/tracer transport model CATT-BRAMS used in the present case as pseudo one-dimensional model with chemistry of CH4, CO, HOx, NOx, NOy and Ox. They include the main possible reactions of the intermediate brominated peroxy radica...

  16. Meteorological controls on the vertical distribution of bromine monoxide in the lower troposphere

    OpenAIRE

    Peterson, P K; Simpson, W. R.; K. A. Pratt; P. B. Shepson; U. Frieß; J. Zielcke; Platt, U.; Walsh, S J; S. V. Nghiem

    2014-01-01

    Multiple axis differential absorption spectroscopy (MAX-DOAS) measurements of bromine monoxide (BrO) probed the vertical structure of halogen activation events during March–May 2012 at Barrow, Alaska. An analysis of the BrO averaging kernels and degrees of freedom obtained by optimal-estimation-based inversions from raw MAX-DOAS measurements reveals the information is best represented by reducing the retrieved BrO profile to two ...

  17. MISCIBILITY AND MORPHOLOGY OF THIN FILMS OF BLENDS OF POLYSTYRENE WITH BROMINATED POLYSTYRENES: EFFECTS OF VARYING THE MOLECULAR WEIGHT,BROMINATION DEGREE AND ANNEALING

    Institute of Scientific and Technical Information of China (English)

    Rui Song; De-bin Yang; Ling-hao He; Guang-tao Yao

    2006-01-01

    Thin films of incompatible polymer blends can form a variety of structures during preparation and subsequent annealing process. For the polymer blend system consisting of polystyrene and poly(styrene-co-p-bromo-styrene), I.e.,PS/PBrxS, its compatibility could be adjusted by varying the degree of bromination and the molecular weight of both components comprised. In this paper, surface chemical compositions of the cast and the annealing films were investigated by X-ray photoelectron spectroscopy (XPS) and contact angle measurement; meanwhile, surface topographical changes are followed by atomic force microscopy (AFM). In addition, substantial attention was paid to the effect of annealing on the morphologic variations induced by phase separation and/or dewetting of the thin film. Moreover, the influences of the molecular weight, Mw, as well as the brominated degree, x%, on the sample surface are explored systematically, and the corresponding observations are explained in virtue of the Flory-Huggins theory, along with the dewetting of the polymer thin film.

  18. Monitoring of WEEE plastics in regards to brominated flame retardants using handheld XRF.

    Science.gov (United States)

    Aldrian, Alexia; Ledersteger, Alfred; Pomberger, Roland

    2015-02-01

    This contribution is focused on the on-site determination of the bromine content in waste electrical and electronic equipment (WEEE), in particular waste plastics from television sets (TV) and personal computer monitors (PC) using a handheld X-ray fluorescence (XRF) device. The described approach allows the examination of samples in regards to the compliance with legal specifications for polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) directly after disassembling and facilitates the sorting out of plastics with high contents of brominated flame retardants (BFRs). In all, over 3000 pieces of black (TV) and 1600 pieces of grey (PC) plastic waste were analysed with handheld XRF technique for this study. Especially noticeable was the high percentage of pieces with a bromine content of over 50,000ppm for TV (7%) and PC (39%) waste plastics. The applied method was validated by comparing the data of handheld XRF with results obtained by GC-MS. The results showed the expected and sufficiently accurate correlation between these two methods. It is shown that handheld XRF technique is an effective tool for fast monitoring of large volumes of WEEE plastics in regards to BFRs for on-site measurements. PMID:25464945

  19. Computer simulation of the cluster destruction of stratospheric ozone by bromine

    Institute of Scientific and Technical Information of China (English)

    A.E.Galashev; O.R.Rakhmanova

    2012-01-01

    The interaction of (Br-)i(H2O)50-i,0≤i≤6 clusters with oxygen and ozone molecules is investigated by the method of molecular dynamics simulation.The ozone molecules as well as the bromine ions do not leave the cluster during the calculation of 25 ps.The ability of the cluster containing molecular oxygen to absorb the infrared (IR)radiation is reduced in the frequency range of 0 ≤ ω ≤ 3500 cm-1 when the number of the bromine ions in the cluster grows.The intensity of the Raman spectrum is not changed significantly when the Br-ions are added to the ozonecontaining system.The power of the emitted IR radiation is increased when the number of bromine ions grows in the oxygen-containing system.The data obtained in this study on the IR and the Raman spectra of the water clusters that contain ozone,oxygen,and Br-can be used to develop an investigation of the mechanisms of ozone depletion.

  20. Measurement and human exposure assessment of brominated flame retardants in household products from South China

    International Nuclear Information System (INIS)

    Brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs), and decabromodiphenyl ethane (DBDPE) were examined in household products in the Pearl River Delta, South China, including electronic appliances, furniture and upholstery, car interiors, and raw materials for electronics. The concentrations of PBDEs derived from penta-BDE mixture were much lower (<111 ng/g) than those for octa- and deca-BDE commercially derived PBDEs, with maximum values of 15,107 and 1,603,343 ng/g, respectively, in all the household products. Our findings suggest the recycling of old electronic products and their reuse might be also a potential important source of discontinued PBDEs to the environment. DBDPE was found in 20.0% of all the samples, ranging from 311 to 268,230 ng/g. PBDE congener profiles in both the household products and raw materials suggest that some less brominated BDEs in the environment may be derived from the decomposition of higher brominated PBDEs in PBDE-containing products in process of the manufacturing, use and/or recycling. Human exposure to PBDEs from household products via inhalation ranged from 175 to 612 pg/kg bw day, accounting for a small proportion of the total daily exposure via indoor inhalation. Despite the low deleterious risk associated with household products with regard to PBDEs, they are of special concern because of the relatively higher exposures observed for young children and further work is required.

  1. Computer simulation of the cluster destruction of stratospheric ozone by bromine

    International Nuclear Information System (INIS)

    The interaction of (Br−)i(H2O)50−i, 0 ≤ i ≤ 6 clusters with oxygen and ozone molecules is investigated by the method of molecular dynamics simulation. The ozone molecules as well as the bromine ions do not leave the cluster during the calculation of 25 ps. The ability of the cluster containing molecular oxygen to absorb the infrared (IR) radiation is reduced in the frequency range of 0 ≤ ω ≤ 3500 cm−1 when the number of the bromine ions in the cluster grows. The intensity of the Raman spectrum is not changed significantly when the Br− ions are added to the ozone-containing system. The power of the emitted IR radiation is increased when the number of bromine ions grows in the oxygen-containing system. The data obtained in this study on the IR and the Raman spectra of the water clusters that contain ozone, oxygen, and Br− can be used to develop an investigation of the mechanisms of ozone depletion

  2. Bromine recovery in residual solutions generated in the 15 N isotopic determination methodology (Rittenberg, 1946)

    International Nuclear Information System (INIS)

    The isotopic determination of 15 N (Rittenberg, 1946) is a methodology used in the Laboratory of Isotope Stable (CENA/USP). In this procedure, in the oxidation of nitrogen species for N2, solution of Li Br O is used, generating as residue 50 L y-1 of solution contends Li Br and Li Br O. Seeking to recover the bromine contained in that residue, very toxic substance, a special line was built composed by reaction balloons (1 and 2 liters), addition funnel, gas flow regulator and connections in glass. In the system proposed, after the acidification (sulfuric acid) of the alkaline residual solution, the liberated bromine (Br2) it was then dragged by flow of nitrogen and reacted with solution of LiOH. That reaction facilitated the production of Li Br O in solution (Efficiency = 82±2%), that was reused later on same analytic procedure. The high cost of the liquid bromine is another attractiveness that corroborates the employment of the developed procedure. They took place isotopic determinations using the recovered solutions and prepared, and the observed values didn't show statistical difference (T test of Student). The presented procedure is part of the Management Program of Chemical Residues of CENA/USP, which seeks to destine the residues of responsibility of the institution appropriately, forming professionals to the practices of environmental management. (author)

  3. A satellite based study of tropospheric bromine explosion events and their linkages to polar cyclone development

    Science.gov (United States)

    Blechschmidt, Anne-Marlene; Richter, Andreas; Burrows, John P.; Kaleschke, Lars; Strong, Kimberly; Theys, Nicolas; Weber, Mark; Zhao, Xiaoyi; Zien, Achim; Hodges, Kevin I.

    2016-04-01

    Intense, cyclone-like shaped plumes of tropospheric bromine monoxide (BrO) are regularly observed by the UV-vis satellite instruments GOME-2/MetOp-A and SCIAMACHY/Envisat over Arctic and Antarctic sea ice in polar spring. The plumes are associated with an autocatalytic chemical chain reaction involving tropospheric ozone depletion and initiated by the release of bromine from cold brine-covered ice or snow to the atmosphere. This influences atmospheric chemistry as it affects the oxidising capacity of the troposphere through OH production and may also influence the local weather/temperature of the polar atmosphere, as ozone is a major greenhouse gas. Here, we make combined use of satellite retrievals and numerical model simulations to study individual BrO plume cases in the polar atmosphere. In agreement with previous studies, our analysis shows that the plumes are often transported by high latitude cyclones, sometimes over several days despite the short atmospheric lifetime of BrO. Moreover, general characteristics of bromine explosion events linked to transport by polar weather systems, such as frequency, spatial distribution and favourable weather conditions are derived based on a new detection method. Our results show that BrO cyclone transport events are by far more common in the Antarctic than in the Arctic.

  4. 30 CFR 816.79 - Protection of underground mining.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Protection of underground mining. 816.79 Section 816.79 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PERMANENT PROGRAM PERFORMANCE STANDARDS PERMANENT PROGRAM PERFORMANCE STANDARDS-SURFACE...

  5. 40 CFR 86.343-79 - Chart reading.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Chart reading. 86.343-79 Section 86.343-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... reading. (a) A computer or any other automatic data processing device(s) may be used as long as the...

  6. 7 CFR 2.79 - Administrator, Agricultural Marketing Service.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Administrator, Agricultural Marketing Service. 2.79... for Marketing and Regulatory Programs § 2.79 Administrator, Agricultural Marketing Service. (a... the Administrator, Agricultural Marketing Service: (1) Exercise the functions of the Secretary...

  7. 36 CFR 7.79 - Amistad Recreation Area.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Amistad Recreation Area. 7.79... REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.79 Amistad Recreation Area. (a) Hunting. (1) Hunting is... (PWC). (1) PWCs are allowed within Amistad National Recreation Area with the following exceptions:...

  8. 47 CFR 79.1 - Closed captioning of video programming.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Closed captioning of video programming. 79.1... CLOSED CAPTIONING AND VIDEO DESCRIPTION OF VIDEO PROGRAMMING § 79.1 Closed captioning of video programming. (a) Definitions. For purposes of this section the following definitions shall apply: (1)...

  9. 47 CFR 79.3 - Video description of video programming.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Video description of video programming. 79.3... CLOSED CAPTIONING AND VIDEO DESCRIPTION OF VIDEO PROGRAMMING § 79.3 Video description of video programming. (a) Definitions. For purposes of this section the following definitions shall apply:...

  10. 34 CFR 101.79 - Cross-examination.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Cross-examination. 101.79 Section 101.79 Education Regulations of the Offices of the Department of Education OFFICE FOR CIVIL RIGHTS, DEPARTMENT OF EDUCATION...-examination. A witness may be cross-examined on any matter material to the proceeding without regard to...

  11. 28 CFR 79.75 - Procedures for payment of claims.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Procedures for payment of claims. 79.75 Section 79.75 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE RADIATION... awarded under the Act and to verify the identity of the claimant or, in the case of a deceased...

  12. 28 CFR 16.79 - Exemption of Pardon Attorney System.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Exemption of Pardon Attorney System. 16.79 Section 16.79 Judicial Administration DEPARTMENT OF JUSTICE PRODUCTION OR DISCLOSURE OF MATERIAL... recommendations to the President in clemency matters, and disclose the identity of persons who...

  13. 46 CFR 111.79-15 - Receptacles for refrigerated containers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Receptacles for refrigerated containers. 111.79-15... ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Receptacles § 111.79-15 Receptacles for refrigerated containers. Receptacles for refrigerated containers must meet one of the following: (a) Each receptacle for...

  14. 28 CFR 79.4 - Determination of claims and affidavits.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Determination of claims and affidavits. 79.4 Section 79.4 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE... the claimant's uranium mining employment history for purposes of determining working level months...

  15. 7 CFR 1753.79 - Construction by force account.

    Science.gov (United States)

    2010-01-01

    ... project number, shall be kept to record labor and materials used as construction is performed. (c) The... 7 Agriculture 11 2010-01-01 2010-01-01 false Construction by force account. 1753.79 Section 1753... § 1753.79 Construction by force account. The borrower shall require that: (a) Minor construction by...

  16. 40 CFR 79.32 - Motor vehicle gasoline.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Motor vehicle gasoline. 79.32 Section...) REGISTRATION OF FUELS AND FUEL ADDITIVES Designation of Fuels and Additives § 79.32 Motor vehicle gasoline. (a) The following fuels commonly or commercially known or sold as motor vehicle gasoline are...

  17. 45 CFR 400.79 - Development of an employability plan.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Development of an employability plan. 400.79... Requirements for Employability Services and Employment General Requirements § 400.79 Development of an employability plan. (a) An individual employability plan must be developed as part of a family...

  18. 40 CFR 79.33 - Motor vehicle diesel fuel.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Motor vehicle diesel fuel. 79.33... (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Designation of Fuels and Additives § 79.33 Motor vehicle diesel fuel. (a) The following fuels commonly or commercially known or sold as motor vehicle diesel...

  19. Targeted Delivery of Immunomodulators to Lymph Nodes

    OpenAIRE

    Jamil Azzi; Qian Yin; Mayuko Uehara; Shunsuke Ohori; Li Tang; Kaimin Cai; Takaharu Ichimura; Martina McGrath; Omar Maarouf; Eirini Kefaloyianni; Scott Loughhead; Jarolim Petr; Qidi Sun; Mincheol Kwon; Stefan Tullius

    2016-01-01

    Active-targeted delivery to lymph nodes represents a major advance toward more effective treatment of immune-mediated disease. The MECA79 antibody recognizes peripheral node addressin molecules expressed by high endothelial venules of lymph nodes. By mimicking lymphocyte trafficking to the lymph nodes, we have engineered MECA79-coated microparticles containing an immunosuppressive medication, tacrolimus. Following intravenous administration, MECA79-bearing particles showed marked accumulation...

  20. Surface Snowpack Key to Bromine Activation in a Changing Arctic Environment

    Science.gov (United States)

    Pratt, Kerri; Custard, Kyle; Shepson, Paul; Douglas, Thomas; Pöhler, Denis; Stephan, General; Zielcke, Johannes; Simpson, William; Platt, Ulrich; von Glasow, Roland; Tanner, David; Huey, L. Gregory; Carlsen, Mark; Stirm, Brian

    2013-04-01

    Arctic sea ice is rapidly declining and transforming from a multiyear ice pack to thinner, more saline, seasonal ice, which has important implications for Arctic atmospheric composition. Following springtime polar sunrise, "ozone depletion events", attributed to bromine chemistry, lead to episodic decreases in lower tropospheric ozone concentrations to near zero, concurrent with mercury depletion and deposition. Despite our increasing understanding of the spatial variability of BrO and possible reaction pathways based on laboratory studies, important questions remain regarding the most efficient sources of and mechanisms for Arctic halogen activation. During the March-April 2012 BRomine, Ozone, and Mercury EXperiment (BROMEX) in Barrow, Alaska, outdoor chamber experiments with snow and ice samples were conducted. Ozone was added as the precursor oxidant, and the samples were investigated with and without ambient sunlight. Samples included first-year sea ice, brine icicles, several layers of snow above first-year sea ice, and seasonal snow above the tundra. Chemical ionization mass spectrometry was utilized to monitor Br2 production. Tundra snow and surface snow above sea ice produced the most Br2, with no production resulting from sea ice and basal snow directly above sea ice. Overall, the most efficient Br2 production was observed from snow samples characterized by lower pH and higher bromide/chloride ratios. Br2 was only observed in the presence of sunlight, indicating the role of snowpack photochemical reactions and the hydroxyl radical in its production. Br2 production via the surface snowpack explains previously-observed BrO enhancements above sea ice, as well as observations of inland tundra hotspots in measured BrO by aircraft-based nadir MAX-DOAS (Multi Axis-Differential Optical Absorption Spectroscopy) measurements, conducted during BROMEX. The findings indicate that atmospherically processed snow is likely a major source of Arctic bromine release, which

  1. Bromine monoxide / sulphur dioxide ratios in relation to volcanological observations at Mt. Etna 2006–2009

    Directory of Open Access Journals (Sweden)

    G. Giuffrida

    2012-12-01

    Full Text Available Over a 3-yr period, from 2006 to 2009, frequent scattered sunlight DOAS measurements were conducted at Mt. Etna at a distance of around 6 km downwind from the summit craters. During the same period and in addition to these measurements, volcanic observations were made by regularly visiting various parts of Mt. Etna. Here, results from these measurements and observations are presented and their relation is discussed. The focus of the investigation is the bromine monoxide/sulphur dioxide (BrO / SO2 ratio, and its variability in relation to volcanic processes. That the halogen/sulphur ratio can serve as a precursor or indicator for the onset of eruptive activity was already proposed by earlier works (e.g. Noguchi and Kamiya 1963; Menyailov, 1975; Pennisi and Cloarec, 1998; Aiuppa et al., 2002. However, there is still a limited understanding today because of the complexity with which halogens are released, depending on magma composition and degassing conditions. Our understanding of these processes is far from complete, for example of the rate and mechanism of bubble nucleation, growth and ascent in silicate melts (Carroll and Holloway, 1994, the halogen vapour-melt partitioning and the volatile diffusivity in the melt (Aiuppa et al., 2009. With this study we aim to add one more piece to the puzzle of what halogen/sulphur ratios might tell about volcanic activities. Our data set shows an increase of the BrO / SO2 ratio several weeks prior to an eruption, followed by a decline before and during the initial phase of eruptive activities. Towards the end of activity or shortly thereafter, the ratio increases to baseline values again and remains more or less constant during quiet phases. To explain the observed evolution of the BrO / SO2 ratio, a first empirical model is proposed. This model suggests that bromine, unlike chlorine and fluorine, is less soluble in the magmatic melt than sulphur. By using the DOAS method to determine SO2, we actually

  2. The effect of ROCK-1 activity change on the adhesive and invasive ability of Y79 retinoblastoma cells

    International Nuclear Information System (INIS)

    Retinoblastoma (Rb) is the most common intraocular tumor in childhood worldwide. It is a deadly pediatric eye cancer. The main cause of death in Rb patients is intracranial and systemic metastasis. ROCK is the main downstream effector of Ras-homologous (Rho) family of GTPases which are involved in many cellular functions, such as cell proliferation, invasion and metastasis. Overexpression of ROCK promotes invasion and metastasis of many solid tumors. However, the effect of ROCK in Rb is largely unknown. ROCK-1 and ROCK-2 mRNA expression in Y79 cell lines were examined by RT-PCR. Protein expression in the Y79 cell line were examined by western blot analyses. ROCK-1 and ROCK-2 siRNA were transfected into Y79 cells with Lipofectamine 2000. Cell proliferation was evaluated by CCK-8 assay after exposure to ROCK inhibitor (Y-27632). We examined the effect of ROCK inhibitors (Y-27632, ROCK-1 and ROCK-2 siRNA) on Y79 cell adhesive capacity by cell adhesion assay. Cell invasion assay through matrigel was used to study the effect of ROCK inhibitors on Y79 cell invasive capacity. The expression of mRNA of ROCK-1 was more than that of ROCK-2 in the Y79 cell line. The protein expression levels of ROCK-1 and ROCK-2 were downregulated in the cells transfected with siRNA. Y-27632 treatment didn’t lead to any changes of Y79 cells proliferation. Adhesive ability of Y79 cells was enhanced following Y-27632 or ROCK-1 siRNA treatment. The invasive capacity of Y79 cells showed an inverse relationship with increasing Y-27632 concentration. Invasiveness of Y79 cells also decreased in Y79 cells transfected with ROCK-1 siRNA. However, there was no change in adhesive ability or invasive capacity in Y79 cells transfected with siRNA against ROCK-2. The findings of this study demonstrate that ROCK-1 protein plays a key role in regulating metastasis and invasion of Y79 cells, suggesting that the ROCK-1 dependent pathway may be a potential target for therapy of Rb

  3. Bromine-80m-labeled estrogens: Auger-electron emitting, estrogen receptor-directed ligands with potential for therapy of estrogen receptor positive cancers

    International Nuclear Information System (INIS)

    A triphenylbromoethylene, 1,1-bis(p-hydroxyphenyl)-2-bromo-2-phenylethylene, Br-BHPE, and a bromosteroidal estrogen, 17α- bromovinylestradiol, BrVE2, were labeled with the Auger electron emitting nuclide bromine-80m, prepared by the [p,n] reaction with 80Se. To assess their potential as estrogen receptor (ER) directed therapeutic substrates the bromine-80m labeled estrogens were injected into immature female rats and the tissue distribution studied at 0.5 and 2 hours. Both radiobromoestrogens showed substantial diethylstilbesterol (DES)-inhibitable localization in the ER rich tissues, uterus, pituitary, ovary and vagina at both time points. While the percent dose per gram tissue was higher for the Br-BHPE, the BrVE2 showed higher tissue to blood ratios, especially at 2 hr, reflecting the lower blood concentrations of radiobromine following administration of the steroidal bromoestrogen. Comparing intraperitoneal, intravenous and subcutaneous routes of administration for the radiobromine labeled Br-BHPE, the intraperitoneal route was particularly advantageous to provide maximum, DES-inhibitable concentrations in the peritoneal, ER-rich target organs, the uterus, ovary and vagina. While uterine concentrations after BrBHPE were from 10--48% dose/g and after BrVE2 were 15--25% dose/g, similar treatment with /sup 80m/Br as sodium bromide showed uniform low concentrations in all tissues at about the levels seen in blood. The effective specific activity of [/sup 80m/Br]BrBHPE, assayed by specific binding to ER in rat uterine cytosol, was 8700 Ci/mmole. 23 refs., 9 figs., 2 tabs

  4. Production of HBR from bromine and steam for off-peak electrolytic hydrogen generation

    Energy Technology Data Exchange (ETDEWEB)

    Schlief, R.E.; Hanrahan, R.J.; Stoy, M.A. [Univ. of Florida, Gainesville, FL (United States)] [and others

    1995-09-01

    Progress is reported on the development of a renewable energy source based solar-electrolytic system for production of hydrogen and oxygen. It employs water, bromine, solar energy and supplemental electrical power. The concept is being developed by Solar Reactor Technologies, Inc., (SRT), with the U.S. Department of Energy (DOE). An overview of the nature and objectives of this program is provided here, and technical progress made during the first (three-month) performance period of the Phase I work effort is reported. The SRT concept entails (1) absorption of concentrated solar radiation by bromine vapor Br{sub 2(g)} in a high-temperature reactor producing Br{sub (g)} atoms, (2) reaction of Br{sub (g)} with water yielding hydrogen bromide (HBr), and (3) electrolysis of stored hydrogen bromide for production of H{sub 2(g)} and recovery of Br{sub 2(I)}. Incorporation of solar radiation in the primary photochemical step (1) reduces by 50 - 70% the electrical power required to split water. The SRT concept is very attractive from an economic viewpoint as well. The reversible fuel cell, employed in the SRT electrolysis concept is capitalized via its use in load leveling by the utility. A 1 kW solar reactor was designed and constructed during the first three-month performance period by SRT personnel at the University of Florida, Gainesville. It was employed in taking survey data of the reaction between bromine and steam at temperatures between 900 and 1300 K. This reaction was run under purely thermal conditions, i.e. in the absence of solar photons. The experimental data are reported and interpreted employing concomitant thermodynamic calculations. The anticipated improvement is discussed briefly as well as the effect of a photochemical boost to the reaction. The amount of this enhancement will be studied in the next three month performance period.

  5. Molecular simulations and density functional theory calculations of bromine in clathrate hydrate phases

    International Nuclear Information System (INIS)

    Bromine forms a tetragonal clathrate hydrate structure (TS-I) very rarely observed in clathrate hydrates of other guest substances. The detailed structure, energetics, and dynamics of Br2 and Cl2 in TS-I and cubic structure I (CS-I) clathrate hydrates are studied in this work using molecular dynamics and quantum chemical calculations. X-ray diffraction studies show that the halogen-water–oxygen distances in the cages of these structures are shorter than the sum of the van der Waals radii of halogen and oxygen atoms. This suggests that the stabilizing effects of halogen bonding or other non-covalent interactions (NCIs) may contribute to the formation of the unique tetragonal bromine hydrate structure. We performed molecular dynamics simulations of Br2 and Cl2 clathrate hydrates using our previously developed five-site charge models for the dihalogen molecules [Dureckova et al. Can. J. Chem. 93, 864 (2015)] which reproduce the computed electrostatic potentials of the dihalogens and account for the electropositive σ-hole of the halogen bond donor (the dihalogen). Analysis of the radial distribution functions, enthalpies of encapsulation, velocity and orientation autocorrelation functions, and polar angle distributions are carried out for Br2 and Cl2 guests in various cages to contrast the properties of these guests in the TS-I and CS-I phases. Quantum chemical partial geometry optimizations of Br2 and Cl2 guests in the hydrate cages using the M06-2X functional give short halogen-water distances compatible with values observed in X-ray diffraction experiments. NCI plots of guest-cage structures are generated to qualitatively show the relative strength of the non-bonding interactions between dihalogens and water molecules. The differences between behaviors of Br2 and Cl2 guests in the hydrate cages may explain why bromine forms the unique TS-I phase

  6. Trophic transfer of naturally produced brominated aromatic compounds in a Baltic Sea food chain.

    Science.gov (United States)

    Dahlgren, Elin; Lindqvist, Dennis; Dahlgren, Henrik; Asplund, Lillemor; Lehtilä, Kari

    2016-02-01

    Brominated aromatic compounds (BACs) are widely distributed in the marine environment. Some of these compounds are highly toxic, such as certain hydroxylated polybrominated diphenyl ethers (OH-PBDEs). In addition to anthropogenic emissions through use of BACs as e.g. flame retardants, BACs are natural products formed by marine organisms such as algae, sponges, and cyanobacteria. Little is known of the transfer of BACs from natural producers and further up in the trophic food chain. In this study it was observed that total sum of methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and OH-PBDEs increased in concentration from the filamentous red alga Ceramium tenuicorne, via Gammarus sp. and three-spined stickleback (Gasterosteus aculeatus) to perch (Perca fluviatilis). The MeO-PBDEs, which were expected to bioaccumulate, increased in concentration accordingly up to perch, where the levels suddenly dropped dramatically. The opposite pattern was observed for OH-PBDEs, where the concentration exhibited a general trend of decline up the food web, but increased in perch, indicating metabolic demethylation of MeO-PBDEs. Debromination was also indicated to occur when progressing through the food chain resulting in high levels of tetra-brominated MeO-PBDE and OH-PBDE congeners in fish, while some penta- and hexa-brominated congeners were observed to be the dominant products in the alga. As it has been shown that OH-PBDEs are potent disruptors of oxidative phosphorylation and that mixtures of different congener may act synergistically in terms of this toxic mode of action, the high levels of OH-PBDEs detected in perch in this study warrants further investigation into potential effects of these compounds on Baltic wildlife, and monitoring of their levels. PMID:26517387

  7. The measurement of bromine monoxide from Fairbanks, AK and comparison with OMI/AURA

    Science.gov (United States)

    Mount, G. H.; Spinei, E.; Herman, J. R.; Cede, A.; Abuhassan, N.; Simpson, W. R.; McPeters, R. D.; Bhartia, P. K.; Johnson, B. J.; Salawitch, R. J.; Canty, T. P.; Chance, K.; Kurosu, T. P.; Suleiman, R. M.

    2011-12-01

    Enhanced column bromine monoxide in the Arctic has been observed by satellites for some time and is related to bromine "hotspots" that result in nearly complete removal of surface ozone in springtime. Salawitch et al. (2010) have demonstrated that these enhancements show little relation, at times, to satellite-enhanced column BrO. Several recent studies have shown that closure of the budget for total column BrO is achieved by summing observed tropospheric partial column BrO with a calculated stratospheric partial column that accounts for the supply of 7 ppt of Bry from natural, short-lived biogenic bromocarbons to the lowermost stratosphere. However, the burden of Bry in the upper stratosphere in these studies, 26 ppt, is at the upper limit of Bry levels inferred from upper stratospheric BrO. A ground-based NASA-sponsored field campaign was held in Fairbanks, AK in March and April 2011 to measure bromine monoxide and other trace gases by direct sun and multi-axis scattered skylight in combination with daily ozonesondes and OMI/AURA satellite data of BrO. The tropospheric contribution to column BrO should be near zero at this time/location. The campaign was therefore focused on defining the stratospheric BrO burden and evaluating the accuracy of total column BrO reported by OMI. The comparison of the ground-based BrO data with the OMI data is reported. Additionally, the DOAS derivation of BrO is explored using various spectral fitting windows and an error budget compiled showing the sensitivity of the deduced BrO vertical column with instrument-dependent spectral window.

  8. Thermodynamic properties of bromine fluorene derivatives: An experimental and computational study

    International Nuclear Information System (INIS)

    Highlights: • Vapour pressures of two bromine derivatives of fluorene were measured. • Combustion energies of two bromine derivatives of fluorene were determined. • Standard molar ΔH, ΔS and ΔG of sublimation and vapourisation were derived. • Standard molar ΔH, ΔS and ΔG of formation in crystal and gas phases were calculated. • Gas phase ΔH of formation was also estimated by quantum chemical calculations. - Abstract: This report presents a comprehensive experimental and computational study of the thermodynamic properties of two bromine fluorene derivatives: 2-bromofluorene and 2,7-dibromofluorene. The standard (p° = 0.1 MPa) molar enthalpies of formation in the crystalline phase of these compounds were derived from the standard molar energies of combustion, in oxygen, at T = 298.15 K, measured by rotating bomb combustion calorimetry. The vapour pressures of the crystalline phase of the two compounds were measured using the Knudsen effusion method and a static method that has also been used to measure the liquid vapour pressures of 2-bromofluorene. From these results the standard molar enthalpies, entropies and Gibbs energies of sublimation of the two compounds studied and of vapourisation of 2-bromofluorene were derived. The enthalpies and temperatures of fusion were determined from DSC experiments. Derived results of standard enthalpies and Gibbs energies of formation, in both gaseous and crystalline phases, were compared with the ones reported in the literature for fluorene. The experimental values of the gas-phase enthalpies of formation of each compound were compared with estimates based on density functional theory calculations using the B3LYP hybrid exchange–correlation energy functional with the 6-311++G(d,p) basis set

  9. With bromine against mercury. Reduction of emission of mercury from combustion gases by 90 % minimally; Mit Brom gegen Quecksilber. Hg-Emissionen aus Verbrennungsabgasen um mindestens 90 % senken

    Energy Technology Data Exchange (ETDEWEB)

    Kanefke, Rico [Currenta GmbH und Co. OHG, Leverkusen (Germany)

    2009-01-15

    Emission of mercury is a global problem. If mercury once arrived into the environment, it remains there for a long period of time and increasingly becomes a strain for humans. In particular, the combustion of coal releases mercury. Under this aspect, the author of the contribution under consideration reports on a new procedure to an almost complete separation of mercury from exhaust gases. The complete oxidation of mercury in the flue gas is the basis to the improved separation of mercury. During bromination of mercury in the cooling down flue gas of boilers, mercury bromide is developed. Bromine is given as a bromine compound such as calcium bromide to the fuel such as coal. At temperatures greater than 1,000 Celsius, at first hydrogen bromide is developed which is converted to bromine by means of the bromine-Deacon-process during cooling. At temperatures below 100 Celsius, the formed bromine reacts with sulphur dioxide so that bromine is available in the entire reaction vessel for the oxidation of mercury. With comparable amount of SO{sub 2}, the oxidation of mercury with bromine is at least 25 times more efficient than the oxidation with chlorine. After this, mercury bromide is separated in the wet scrubber and precipitated during the treatment of rinsing water. Then the resulting mercury sulphide is separated as a filter cake from the water and spent on the dump. Thus, mercury is withdrawn from the atmospheric mercury cycle.

  10. Assessment of PCDD/F and PBDD/F Emissions from Coal-fired Power Plants during Injection of Brominated Activated Carbon for Mercury Control

    Science.gov (United States)

    The effect of the injection of brominated powdered activated carbon (Br-PAC) on the emission of brominated and chlorinated dioxins and furans in coal combustion flue gas has been evaluated. The tests were performed at two U.S. Department of Energy (DOE) demonstration sites where ...

  11. Reaction modelling of Iron Oxide Bromination in the UT-3 thermochemical cycle for Hydrogen production from water

    International Nuclear Information System (INIS)

    Analysis modelling of the iron oxide bromination had been carried out using experiment data from the iron oxide bromination in the UT-3 thermochemical cycle. Iron oxide in the form of pellets were made of the calcination of the mixture of iron oxide, silica, graphite and cellulose at 1473 K. Thermobalance reactor was used to study the kinetic reactions of the iron oxide bromination at a temperature of 473 K for 2 - 6 hours. The data collected from the experiments were used as input for the common models. However, none of these models could not explain the result of the experiments. A new model, a combination of two kinetic reactions : exposed particle and coated particle was created and worked successfully

  12. Origin of bromine in ancient sutras of the Otani collection. PIXE application to preservation of cultural assets

    International Nuclear Information System (INIS)

    Some small fragments of rag paper - made more than a thousand and a few hundred years ago, and excavated at Turfan, west of China by the Otani-expedition dispatched there during the late Meiji and the Taisho eras - were measured by PIXE. Bromine was highly detected in all of these ancient fragments and modern paper samples that had been placed together with these Turfan manuscripts. In other paper samples, bromine could not be detected (H+, 4 MeV, 50 μC and H+, 2 MeV, 100 μC) and their average concentration was about 1.1 ppm (S.D. = 1.11 ppm, N = 15, 0.3 - 3.4 ppm). The bromine contamination of ancient sutras is mainly caused by larvicide of methyl bromide, and the observation suggests that the ancient manuscripts might be spoiled gradually by agricultural chemicals for protecting them from vermin. (author)

  13. Enriched concentrations of bromine, chlorine, and iodine in urban rainfall as determined by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Concentrations of bromine, chlorine and iodine were determined in bulk rain as part of a detailed urban monitoring program. Instrumental neutron activation gives simultaneous non-destructive analysis of these halogens with detection limits of 2, 30 and 1 ng/g for bromine, chlorine, and iodine, respectively. Results for enrichment factor calculations based on crustal, seawater and lake water reference elements were somewhat contradictory. Elemental ratios of Br/Cl, I/Cl, Br/Pb, and Cl/Pb, together with an analysis of chlorine in urban surface materials, support the suggestions that local anthropogenic sources may cause the high bromine and chlorine concentrations observed in urban precipitation while fractionation from an oceanic source is likely responsible for high iodine concentrations. (author)

  14. Natural and anthropogenically-produced brominated compounds in endemic dolphins from Western South Atlantic: Another risk to a vulnerable species

    International Nuclear Information System (INIS)

    Liver samples from 53 Franciscana dolphins along the Brazilian coast were analyzed for organobrominated compounds. Target substances included the following anthropogenic pollutants: polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), as well as the naturally-generated methoxylated-PBDEs (MeO-PBDEs). PBDE concentrations ranged from 6 to 1797 ng/g lw (mean 166 ± 298 ng/g lw) and were similar to those observed in cetaceans from Northern Hemisphere. PBBs were found in all sampling locations (< LOQ to 57 ng/g lw). DBDPE was detected in 42% of the dolphins from the most industrialized Brazilian state and the concentrations ranging from < LOQ to 352 ng/g lw. Franciscana dolphins from the tropical Brazilian shore presented the highest MeO-PBDE concentrations ever reported for coastal cetaceans (up to 14 μg/g lw). Eight MeO-PBDE congeners were detected and the present investigation constituted the first record of occurrence of six of them in marine mammal livers. - Highlights: ► PBDE, emerging BFR and MeO-PBDE levels in Franciscana dolphin from Brazil were reported. ► Six MeO-PBDEs were detected for the first time in marine mammals. ► PBDE contamination was similar than those from other industrialized areas around the world. ► MeO-PBDEs presented the higher concentrations found in coastal biota worldwide. - Concentrations and accumulation profiles of PBDEs, MeO-PBDEs and emerging brominated compounds in livers of dolphins from South Atlantic.

  15. Magnetically enhanced triode etching of large area silicon membranes in a molecular bromine plasma

    International Nuclear Information System (INIS)

    The optimization of a process for etching 125 mm silicon membranes formed on 150 mm wafers and bonded to Pyrex rings is discussed. A magnetically enhanced triode etching system was designed to provide an intense, remote plasma surrounding the membrane while, at the same time, suppressing the discharge over the membrane itself. For the optimized molecular bromine process, the silicon etch rate is 40 nm/min and the selectivity relative to SiO2 is 160:1. 14 refs., 6 figs

  16. Neutron Activation Analysis of Vanadium, Copper, Zinc, Bromine and Iodine in Pyura Microcosmus

    International Nuclear Information System (INIS)

    Most of the tunicates seem to accumulate vanadium more energetically than other marine organisms. However, there is a very great variation within the group. Maximum amounts of vanadium were found in the Ascididae family whereas in some species of the Pyuridae family vanadium was apparently absent. This paper describes the simple and rapid determination by activation analysis of vanadium, copper, zinc, bromine and iodine in Pyura microcosmus, a species of the Pyuridae family. The same elements were also investigated in the environmental sea-water. Samples of P. microcosmus and sea-water were collected from a point about 15 m below the surface in the Saronic Gulf near Athens. All irradiations of samples and standards were carried out with the DEMOCRITUS Reactor of the Nuclear Research Centre of Greece, at a neutron flux of 2 x 1011 n/cm2s. The time of irradiation with the pneumatic transfer system ranged from 1 to 25 min, depending on the element being determined. After irradiation and addition of inactive carriers, the radioisotopes of interest were isolated by fast radiochemical procedures based on solvent extraction techniques. Vanadium and copper were extracted as cupferrates into chloroform, and zinc was extracted with 8% methyldioctylamine into trichloroethylene. Bromine and iodine were distilled first and then separated from each other by selective redox and extraction procedures. The photopeak areas of 52V, 64Cu, 69mZn, 82Br and 128I were measured by means of a multichannel analyser and compared with those of standards of the above radionuclides processed in the same manner. After irradiation the time to complete the analysis ranged from 5 to 35 min depending on the element being determined. The quantities of the elements determined in P. microcosmus, expressed in micrograms per gram of dry matter, were: vanadium 1.0, copper 7.5, iodine 14.1, bromine 406 and zinc 702. The per cent concentration of the same elements found in the sea-water was as follows

  17. SYNTHESIS AND GREEN BROMINATION OF SOME CHALCONES AND THEIR ANTIMICROBIAL SCREENING

    Directory of Open Access Journals (Sweden)

    Mayur R. Adokar

    2013-04-01

    Full Text Available Chalcones are the versatile molecules having the structural flexibility which permits structural transformations into flavonoids, flavanones, pyrazoles, oxazoles, pyrimidines etc. Changes in their structure have offered the development of new medicinal agents having improved pharmacological potency. Their derivatives have attracts increasing attention due to numerous pharmacological potential. In the present communication we report the synthesis of chalcones from various acetophenone derivatives with different aromatic aldehydes and green chemistry approach to their bromination with the help of Tetrabutylammonium Tribromide (TBATB. All the synthesized chalcone dibromides were screened for their antimicrobial activity against Aspergillus flavus, Rhizopus sp., Fusarium solani and Aspergillus niger.

  18. Levels of persistent fluorinated, chlorinated and brominated compounds in human blood collected in Sweden in 1997-2000

    Energy Technology Data Exchange (ETDEWEB)

    Lindstroem, G.; Kaerrman, A.; Bavel, B. van [MTM Research Centre, Oerebro Univ. (Sweden); Hardell, L. [Dept. of Oncology, Univ. Hospital, Oerebro (Sweden); Hedlund, B. [Environmental Monitoring Section, Swedish EPA, Stockholm (Sweden)

    2004-09-15

    Levels of persistent fluorinated, chlorinated and brominated compounds in blood collected from the Swedish population have been determined in connection with several exposure and monitoring studies at the MTM Research Centre. A data base with 631 individual congener specific measurements on halogenated POPs such as dioxins, PCBs, HCB, DDE, chlordanes, PBDEs and PFAs including information on residency, age, BMI, diet, occupation, number of children, smoking habits, immunological status etc. has been compiled from samples collected between 1994 and 2004. A brief overview focusing on levels of some persistent chlorinated, brominated and fluorinated, compounds in blood collected in a background population group (n=83) in 1997-2000 is given here.

  19. Price Wars and the Stability of Collusion: A Study of the Pre-World War I Bromine Industry

    OpenAIRE

    Margaret Levenstein

    1993-01-01

    Bromine producers colluded to raise prices and profits during most of the period between 1885 and 1914. Collusion was punctuated by price wars in which prices fell sharply. The characteristics of these price wars are compared with those in the Green-Porter and Abreu- Pearce-Stachetti models. Some of the bromine price wars resulted from the imperfect monitoring problems in these models. Those price wars were short and mild. More severe price wars were part of a bargaining process, in which fir...

  20. Synchrotron X-ray fluorescence studies of a bromine-labelled cyclic RGD peptide interacting with individual tumor cells

    International Nuclear Information System (INIS)

    The first example of synchrotron X-ray fluorescence imaging of cultured mammalian cells in cyclic peptide research is reported. The study reports the first quantitative analysis of the incorporation of a bromine-labelled cyclic RGD peptide and its effects on the biodistribution of endogenous elements (for example, K and Cl) within individual tumor cells. The first example of synchrotron X-ray fluorescence imaging of cultured mammalian cells in cyclic peptide research is reported. The study reports the first quantitative analysis of the incorporation of a bromine-labelled cyclic RGD peptide and its effects on the biodistribution of endogenous elements (for example, K and Cl) within individual tumor cells

  1. Occurrence and risk assessment of organophosphorus and brominated flame retardants in the River Aire (UK)

    International Nuclear Information System (INIS)

    This study presents the occurrence and risk of PBDEs, new brominated and organophosphorus flame retardants along a river affected by urban and industrial pressures (River Aire, UK). Tris(2-choroethyl) phosphate (TCEP), tris(2-chloro-1-methylethyl) phosphate (TCPP), tris[2-chloro-1-(chloromethyl)ethyl] phosphate (TDCP) and triphenyl phosphate (TPhP) were detected in all samples, with TCPP present at the highest concentrations, ranging from 113 to 26 050 ng L-1. BDE-209 was detected in most of the sampled sites, ranging from 17 to 295 ng L−1, while hexabromobenzene (HBB) and pentabromoethyl benzene (PBEB) were seldom detected. A risk quotients based on predicted no effect concentrations (PNEC) and flame retardants water concentration proved significant risk for adverse effects for algae, Daphnia and fish in sites close to industrial and urban sewage discharges. This study provides a protocol for the risk estimation of priority and new generation flame retardants based on river concentrations and toxicological values. -- Highlights: •Brominated and organophosphorus flame retardants were monitored in River Aire (UK). •BDE-209 and organophosphorus flame retardants were detected at high concentrations. •A risk assessment was performed based on water concentration and acute toxicity data. •Low to significant risk for adverse effects was observed for algae, fish and Daphnia. -- Organophosphorus flame retardants and BDE-209 were detected at high concentrations along River Aire (UK) and a risk assessment indicated significant risk for adverse effects to aquatic organisms

  2. Iodine-123 and bromine-75 production and development program at Juelich

    International Nuclear Information System (INIS)

    The iodine-123 and bromine-75 production and development program at the Nuclear Research Center in Juelich as of 1982 is described, and examples of recent 123I- and 75Br-analogue tracers that have been developed to the level of clinical trial are given. Iodine-123 is produced via the 127I(d,6n)123Xe → 123I process and by the 124Te(p,2n)123I and 122Te(d,n)123I reactions. These production methods are critically reviewed. Bromine-75-labeled benzodiazenes have been prepared for in vivo mapping of benzodiazepine receptor sites. The 7-(75Br)-5-(2-fluorophenyl)-1-methyl-1,3-dihydro-2H-1,4-benzodiazepine-2-one (BFB) was prepared with a specific activity of > 104 Ci/mmole. Finally, preparation and applications of the halogenated amino acid L-3-(123I)-iodo-α-methyltyrosine (IMT) and the analogous 75Br compound (BMT) are reported. Both IMT and BMT have been successfully applied for pancreas imaging and tomography, and IMT has been used for imaging both melanotic and amelanotic malignant melanoma of the eye

  3. Brominated diphenyl ethers in the sediments, porewater, and biota of the Chesapeake Bay, USA

    Energy Technology Data Exchange (ETDEWEB)

    Baker, K.; Klosterhaus, S.; Liebert, D.; Stapleton, H. [Maryland Univ., Solomons, MD (United States)

    2004-09-15

    Levels of brominated diphenyl ethers (BDEs) are rapidly increasing in the environment, and in a short time these chemicals have evolved from 'emerging contaminants' to globally-distributed organic pollutants. Recent research demonstrates BDEs are sufficiently stable to be transported long distances in the environment and to accumulate in higher trophic levels. Photolysis and metabolism appear to be dominant loss processes for the parent compounds, generating a variety of lower brominated diphenyl ethers, hydroxylated metabolites, and other products. BDEs are hydrophobic, and therefore their transport in aquatic systems is likely controlled by sorption to sediments and perhaps exchange across the air-water interface. To date, few studies have examined the geochemistry of BDEs in natural waters. In this paper, we review our recent measurements of BDEs in the Chesapeake Bay, a shallow, productive estuary in eastern North America. We focus on the distribution of BDE congeners sediment, porewater, and in faunal benthos along a contamination gradient downstream from a wastewater treatment plant and on the spatial distribution of BDEs in bottom-feeding and pelagic fish species.

  4. Levelized cost of energy and sensitivity analysis for the hydrogen-bromine flow battery

    Science.gov (United States)

    Singh, Nirala; McFarland, Eric W.

    2015-08-01

    The technoeconomics of the hydrogen-bromine flow battery are investigated. Using existing performance data the operating conditions were optimized to minimize the levelized cost of electricity using individual component costs for the flow battery stack and other system units. Several different configurations were evaluated including use of a bromine complexing agent to reduce membrane requirements. Sensitivity analysis of cost is used to identify the system elements most strongly influencing the economics. The stack lifetime and round-trip efficiency of the cell are identified as major factors on the levelized cost of electricity, along with capital components related to hydrogen storage, the bipolar plate, and the membrane. Assuming that an electrocatalyst and membrane with a lifetime of 2000 cycles can be identified, the lowest cost market entry system capital is 220 kWh-1 for a 4 h discharge system and for a charging energy cost of 0.04 kWh-1 the levelized cost of the electricity delivered is 0.40 kWh-1. With systems manufactured at large scales these costs are expected to be lower.

  5. Dissolution of brominated epoxy resins by dimethyl sulfoxide to separate waste printed circuit boards.

    Science.gov (United States)

    Zhu, Ping; Chen, Yan; Wang, Liangyou; Qian, Guangren; Zhang, Wei Jie; Zhou, Ming; Zhou, Jin

    2013-03-19

    Improved methods are required for the recycling of waste printed circuit boards (WPCBs). In this study, WPCBs (1-1.5 cm(2)) were separated into their components using dimethyl sulfoxide (DMSO) at 60 °C for 45 min and a metallographic microscope was used to verify their delamination. An increased incubation time of 210 min yielded a complete separation of WPCBs into their components, and copper foils and glass fibers were obtained. The separation time decreased with increasing temperature. When the WPCB size was increased to 2-3 cm(2), the temperature required for complete separation increased to 90 °C. When the temperature was increased to 135 °C, liquid photo solder resists could be removed from the copper foil surfaces. The DMSO was regenerated by rotary decompression evaporation, and residues were obtained. Fourier transform infrared spectroscopy (FT-IR), thermal analysis, nuclear magnetic resonance, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were used to verify that these residues were brominated epoxy resins. From FT-IR analysis after the dissolution of brominated epoxy resins in DMSO it was deduced that hydrogen bonding may play an important role in the dissolution mechanism. This novel technology offers a method for separating valuable materials and preventing environmental pollution from WPCBs. PMID:23398278

  6. Stable bromine isotopic composition of methyl bromide released from plant matter

    Science.gov (United States)

    Horst, Axel; Holmstrand, Henry; Andersson, Per; Thornton, Brett F.; Wishkerman, Asher; Keppler, Frank; Gustafsson, Örjan

    2014-01-01

    Methyl bromide (CH3Br) emitted from plants constitutes a natural source of bromine to the atmosphere, and is a component in the currently unbalanced global CH3Br budget. In the stratosphere, CH3Br contributes to ozone loss processes. Studies of stable isotope composition may reduce uncertainties in the atmospheric CH3Br budget, but require well-constrained isotope fingerprints of the source end members. Here we report the first measurements of stable bromine isotopes (δ81Br) in CH3Br from abiotic plant emissions. Incubations of both KBr-fortified pectin, a ubiquitous cell-stabilizing macromolecule, and of a natural halophyte (Salicornia fruticosa), yielded an enrichment factor (ε) of -2.00 ± 0.23‰ (1σ, n = 8) for pectin and -1.82 ± 0.02‰ (1σ, n = 4) for Salicornia (the relative amount of the heavier 81Br was decreased in CH3Br compared to the substrate salt). For short incubations, and up to 10% consumption of the salt substrate, this isotope effect was similar for temperatures from 30 up to 300 °C. For longer incubations of up to 90 h at 180 °C the δ81Br values increased from -2‰ to 0‰ for pectin and to -1‰ for Salicornia. These δ81Br source signatures of CH3Br formation from plant matter combine with similar data for carbon isotopes to facilitate multidimensional isotope diagnostics of the CH3Br budget.

  7. Synthesis of α-Bromine- Terminated Polystyrene Macroinitiator and Its Initiation of MMA Polymerization by ATRP

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In the present paper the synthesis of block copolymers via the transformation from living anionic polymerization (LAP) to atom transfer radical polymerization (ATRP) was described. Α-Bromine-terminated polystyrenes(PStBr) in the LAP step was prepared by using n-BuLi as initiator, tetrahydrofuran (THF) as the activator, α-methylstyrene (α-MeSt) as the capping group and liquid bromine (Br2) as the bromating agent. The effects of reaction conditions such as the amounts of α-MeSt, THF, and Br2 as well as molecular weight of polystyrene on the bromating efficiency (BE) and coupling extent (CE) were examined. The present results show that the yield of PStBr obtained was more than 93.8% and the coupling reaction was substantially absent. PStBr was further used as the macroinitiator in the polymerization of methyl-methacrylate(MMA) in the presence of copper(Ⅰ) halogen and 2,2-bipyridine(bpy) complexes. It was found that the molecular weight of the resulted PSt-b-PMMA increased linearly with the increase of the conversion of MMA and the polydispersity was 1.2-1.6. The structures of PStBr and P(St-b-MMA) were characterized by 1H NMR spectra.

  8. Ultrafast optical limiting properties and transient dynamics of symmetrical phenoxazinium bromine salt

    Science.gov (United States)

    Xiao, Zhengguo; Ge, Jianfeng; Li, Zhongguo; Wu, Xingzhi; Fang, Yu; Shi, Guang; Zhang, Xueru; Wang, Yuxiao; Song, Yinglin

    2015-12-01

    A symmetrical phenoxazinium bromine salt with resonant D-π-D structure was prepared and spectroscopically characterized. The ultrafast nonlinear optical (NLO) response of the compound dissolved in DMF was investigated using open aperture Z-scan method with 190 fs laser pulses at 515 nm. And the photo-physical dynamics of the compound was studied using transient absorption spectra at femtosecond time regime. The titled sample showed strong reverse saturable absorption (RSA) at 515 nm. Transient absorption results demonstrated that the compound exhibited RSA signals at 478-580 nm and SA signals at 600-780 nm. A simplified three-energy-level model was used to determine the photo-physical parameters. And the excited-state lifetime was evaluated to be around one nanosecond. Our results show that the phenoxazinium bromine salt has a large ratio of singlet excited-state absorption cross-section to that of ground state cross-section (18.7), indicating it is a candidate material for future ultrafast optical limiters.

  9. Natural solar photolysis of total organic chlorine, bromine and iodine in water.

    Science.gov (United States)

    Abusallout, Ibrahim; Hua, Guanghui

    2016-04-01

    Municipal wastewater has been increasingly used to augment drinking water supplies due to the growing water scarcity. Wastewater-derived disinfection byproducts (DBPs) may negatively affect the aquatic ecosystems and human health of downstream communities during water reuse. The objective of this research was to determine the degradation kinetics of total organic chlorine (TOCl), bromine (TOBr) and iodine (TOI) in water by natural sunlight irradiation. Outdoor solar photolysis experiments were performed to investigate photolytic degradation of the total organic halogen (TOX) formed by fulvic acid and real water and wastewater samples. The results showed that TOX degradation by sunlight irradiation followed the first-order kinetics with half-lives in the range of 2.6-10.7 h for different TOX compounds produced by fulvic acid. The TOX degradation rates were generally in the order of TOI > TOBr ≅ TOCl(NH2Cl) > TOCl(Cl2). High molecular weight TOX was more susceptible to solar photolysis than corresponding low molecular weight halogenated compounds. The nitrate and sulfite induced indirect TOX photolysis rates were less than 50% of the direct photolysis rates under the conditions of this study. Fulvic acid and turbidity in water reduced TOX photodegradation. These results contribute to a better understanding of the fate of chlorinated, brominated and iodinated DBPs in surface waters. PMID:26841230

  10. Novel Spectrophotometric Method for Determination of Macro-paracetamol via Reaction with Bromine

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The reaction between Br2 and paracetamol(p-AAP) leads to the formation of a coloured product, which can be used for spectrophotometric determination of the p-AAP content in its pure form and in different pharmaceutical preparations with p-AAP. The stoichiometric composition of the reaction was found to be n(p-AAP)∶n(bromine)=1∶3. The effects of pH and time on the spectra of p-AAP-bromine redox reaction product were studied. The interference of different additives on the measured spectra of the obtained product was also studied. The results obtained by the present method were compared with those obtained by the standard method. The F- and t- test values were calculated for both of the applied procedures and they met a confidence level of 99%. The proposed procedure actually needs no separation of these drugs from their sources before analysis and was unaffected by interference of other phenolic compounds. The proposed method is simpler and faster than the repoeted ones.

  11. Selected chlorobornanes, polychlorinated naphthalenes and brominated flame retardants in Bjornoya (Bear Island) freshwater biota

    International Nuclear Information System (INIS)

    Levels of selected sparsely investigated persistent organic pollutants (POPs) have been measured in organisms from two Arctic lakes on Bjornoya (Bear Island). Elevated levels of chlorobornanes (CHBs) (up to 46.7 ng/g wet weight=ww), polybrominated diphenyl ethers (PBDEs) (up to 27.2 ng/g ww), polybrominated biphenyls (PBBs) (up to 1.1 ng/g ww) and polychlorinated naphthalenes (PCNs, only 4 congeners) (up to 62.7 pg/g ww), were measured in biota from Lake Ellasjoen. In Lake Oyangen, located only 5 km north of Ellasjoen, levels of these contaminants were significantly lower. δ15N-values were 7-10%o higher in organisms from Ellasjoen as compared to Oyangen. This is attributed to biological inputs related to seabird activities. The present study illustrates that contaminants such as CHBs, brominated flame retardants and PCNs accumulate in the Ellasjoen food web in a manner similar to PCBs and conventional organochlorine pesticides. Transport mechanisms that control PCB and DDT distributions, i.e. atmospheric long-range transport and biotransport by seabirds, are also relevant for the contaminants investigated in the present study. - Elevate levels of chlorobornanes, polychlorinated naphthalenes and brominated flame retardants have been measured in biota from a Norwegian Arctic lake

  12. Development of Zinc/Bromine Batteries for Load-Leveling Applications: Phase 2 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    CLARK,NANCY H.; EIDLER,PHILLIP

    1999-10-01

    This report documents Phase 2 of a project to design, develop, and test a zinc/bromine battery technology for use in utility energy storage applications. The project was co-funded by the U.S. Department of Energy Office of Power Technologies through Sandia National Laboratories. The viability of the zinc/bromine technology was demonstrated in Phase 1. In Phase 2, the technology developed during Phase 1 was scaled up to a size appropriate for the application. Batteries were increased in size from 8-cell, 1170-cm{sup 2} cell stacks (Phase 1) to 8- and then 60-cell, 2500-cm{sup 2} cell stacks in this phase. The 2500-cm{sup 2} series battery stacks were developed as the building block for large utility battery systems. Core technology research on electrolyte and separator materials and on manufacturing techniques, which began in Phase 1, continued to be investigated during Phase 2. Finally, the end product of this project was a 100-kWh prototype battery system to be installed and tested at an electric utility.

  13. Tropospheric Bromine Chemistry: Implications for Present and Pre-industrial Ozone and Mercury

    Science.gov (United States)

    Parella, J. P.; Jacob, D. J.; Liang, Q.; Zhang, Y.; Mickley, L. J.; Miller, B.; Evans, M. J.; Yang, X.; Pyle, J. A.; Theys, N.; VanRoozendael, M.

    2012-01-01

    We present a new model for the global tropospheric chemistry of inorganic bromine (Bry) coupled to oxidant-aerosol chemistry in the GEOS-Chem chemical transport model (CTM). Sources of tropospheric Bry include debromination of sea-salt aerosol, photolysis and oxidation of short-lived bromocarbons, and transport from the stratosphere. Comparison to a GOME-2 satellite climatology of tropospheric BrO columns shows that the model can reproduce the observed increase of BrO with latitude, the northern mid-latitudes maximum in winter, and the Arctic maximum in spring. This successful simulation is contingent on the HOBr + HBr reaction taking place in aqueous aerosols and ice clouds. Bromine chemistry in the model decreases tropospheric ozone mixing ratios by mercury against oxidation by Br. This suggests that historical anthropogenic mercury emissions may have mostly deposited to northern mid-latitudes, enriching the corresponding surface reservoirs. The persistent rise in background surface ozone at northern mid-latitudes during the past decades could possibly contribute to the observations of elevated mercury in subsurface waters of the North Atlantic.

  14. Small mammal populations in Maryland meadows during four years of herbicide (Brominal? ) applications

    Science.gov (United States)

    Clark, D.R., Jr.; Moulton, C.A.; Hines, J.E.; Hoffman, D.J.

    1996-01-01

    The herbicide Brominal? was applied at the recommended rate to one plot in each of three paired 0.6-ha plots; the other three plots were used as controls. Plots were sprayed once in the fall of 1988 and 1989 and twice in the spring of 1990 and 1991. Small mammals were trapped three times during each activity season (April?October) to obtain population estimates before and after spraying and in the spring preceding fall spraying or the fall following spring spraying. Population estimates immediately after spraying gave no evidence of direct mortality. By 1991, dicot vegetation on treated plots was suppressed and mean numbers of meadow voles (Microtus pennsylvanicus) were less than on control plots. Because meadow voles favor dicots over monocots in their diet, reduced availability of dicots may have been related to the smaller vole population estimates. Species diversity of small mammals was negatively correlated with size of vole populations, but was not different between treated and control plots. Brominal apparently induced opaque corneas in nine voles. The condition was found in two voles too small to have been conceived at the time of the last previous spray nearly 8 months earlier, suggesting exposure to residue alone.

  15. The low radio frequency properties of the SNR Kes 79

    Science.gov (United States)

    Castelletti, G.; Giacani, E.; Paron, S.; Dubner, G.

    2009-05-01

    Observations of the supernova remnants (SNRs) at meter and longer wavelengths are powerful tools to differentiate physical processes taking place either in the SNRs (e.g. shock acceleration) or in the interstellar medium intervening along the line of sight towards them (e.g. thermal absorption). Kes 79 (G33.6+0.1) is a Galactic SNR rich in spatial structures in both, radio and X-ray bands, that make it ideal for addressing questions of SNR physics. Its radio morphology at 1.5 Ghz is dominated by a system of two concentric incomplete shells with diameters about 8' and 12'. Chandra observations of Kes 79 reveal many filaments, multiple partial shells, a loop, and a protrusion. The X-ray point source, CXOUJ 185238.6+004020, located close to the geometric center of the remnant was proposed to be the compact stellar remnant formed in the supernova event, although no evidence for a surrounding pulsar wind nebula was found in the X-rays. It has also been suggested that Kes 79 is interacting with a molecular cloud that appears to be partially surrounding its east and southeast borders. In this work we present new high quality images of Kes 79 obtained at low radio frequencies. The observations at 74 and 324 MHz were carried out using multiple-configurations of the Very Large Array (VLA) of the NRAO. We use these data and existing VLA observations at 1.5 GHz to perform an accurate study of the spectral index behaviour over the remnant and its relationship with the properties in the X-ray band of Kes 79. In addition, using HI and CO data from public databases we investigate the influence of the surrounding gas on the morphology of Kes 79.

  16. Anomalous dose-response characteristics induced by caffeine in ultraviolet-irradiated V79-79 Chinese hamster cells

    International Nuclear Information System (INIS)

    Cultured Chinese hamster cell line V79-79 exhibited an increase in survival with increasing UV fluence after a sharp decrease when exposed to 2.5 mM caffeine for 44 h after far-UV irradiation resulting in an anomalous maximum in the survival curve. No survival maximum was evident when either 0 or 1 mM caffeine is administered under the same conditions. The UV survival curve for 2.5 mM caffeine crossed the corresponding 1 mM curve and apparently became asymptotic to the 0 mM curve as UV fluence was increased. Chinese hamster cell lines V79-753B (related to V79-79 by derivation from the same parental line) and M3-1F3 (unrelated) exhibited only potentiation of post-UV lethality by the same concentration of caffeine and had no caffeine-induced anomalies in their survival curves. Xanthine, used alone or in combination with caffeine, only potentiated a slight amount of lethality and appeared not to be a major causative factor of the anomaly. (author)

  17. Targeted Delivery of Immunomodulators to Lymph Nodes.

    Science.gov (United States)

    Azzi, Jamil; Yin, Qian; Uehara, Mayuko; Ohori, Shunsuke; Tang, Li; Cai, Kaimin; Ichimura, Takaharu; McGrath, Martina; Maarouf, Omar; Kefaloyianni, Eirini; Loughhead, Scott; Petr, Jarolim; Sun, Qidi; Kwon, Mincheol; Tullius, Stefan; von Andrian, Ulrich H; Cheng, Jianjun; Abdi, Reza

    2016-05-10

    Active-targeted delivery to lymph nodes represents a major advance toward more effective treatment of immune-mediated disease. The MECA79 antibody recognizes peripheral node addressin molecules expressed by high endothelial venules of lymph nodes. By mimicking lymphocyte trafficking to the lymph nodes, we have engineered MECA79-coated microparticles containing an immunosuppressive medication, tacrolimus. Following intravenous administration, MECA79-bearing particles showed marked accumulation in the draining lymph nodes of transplanted animals. Using an allograft heart transplant model, we show that targeted lymph node delivery of microparticles containing tacrolimus can prolong heart allograft survival with negligible changes in tacrolimus serum level. Using MECA79 conjugation, we have demonstrated targeted delivery of tacrolimus to the lymph nodes following systemic administration, with the capacity for immune modulation in vivo. PMID:27134176

  18. Targeted Delivery of Immunomodulators to Lymph Nodes

    Directory of Open Access Journals (Sweden)

    Jamil Azzi

    2016-05-01

    Full Text Available Active-targeted delivery to lymph nodes represents a major advance toward more effective treatment of immune-mediated disease. The MECA79 antibody recognizes peripheral node addressin molecules expressed by high endothelial venules of lymph nodes. By mimicking lymphocyte trafficking to the lymph nodes, we have engineered MECA79-coated microparticles containing an immunosuppressive medication, tacrolimus. Following intravenous administration, MECA79-bearing particles showed marked accumulation in the draining lymph nodes of transplanted animals. Using an allograft heart transplant model, we show that targeted lymph node delivery of microparticles containing tacrolimus can prolong heart allograft survival with negligible changes in tacrolimus serum level. Using MECA79 conjugation, we have demonstrated targeted delivery of tacrolimus to the lymph nodes following systemic administration, with the capacity for immune modulation in vivo.

  19. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains: Field measurements and model calculations

    NARCIS (Netherlands)

    Veltman, K.; Hendriks, J.; Huijbregts, M.; Leonards, P.E.G.; Heuvel-Greve, van den M.J.; Vethaak, D.

    2005-01-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and marin

  20. Corrosion mechanism of 13Cr stainless steel in completion fluid of high temperature and high concentration bromine salt

    International Nuclear Information System (INIS)

    Highlights: • The corrosion behavior of 13Cr steel exposed to bromine salt completion fluid containing high concentration bromine ions was investigated. • There are passive circles around pits on the 13Cr steel surface after 7 d of exposure. • Macroscopic galvanic corrosion formed between the passive halo and the pit. • The mechanism of pitting corrosion on 13Cr stainless steel exposed to heavy bromine brine was established. - Abstract: A series of corrosion tests of 13Cr stainless steel were conducted in a simulated completion fluid environment of high temperature and high concentration bromine salt. Corrosion behavior of specimens and the component of corrosion products were investigated by means of scanning electron microscope (SEM), confocal laser scanning microscopy (CLSM) and X-ray photoelectron spectroscopy (XPS). The results indicate that 13Cr steel suffers from severe local corrosion and there is always a passive halo around every pit. The formation mechanism of the passive halo is established. OH− ligand generates and adsorbs in a certain scale because of abundant OH− on the surface around the pits. Passive film forms around each pit, which leads to the occurrence of passivation in a certain region. Finally, the dissimilarities in properties and morphologies of regions, namely the pit and its corresponding passive halo, can result in different corrosion sensitivities and may promote the formation of macroscopic galvanic pairs

  1. Corrosion mechanism of 13Cr stainless steel in completion fluid of high temperature and high concentration bromine salt

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan [Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China); Xu, Lining, E-mail: xulining@ustb.edu.cn [Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China); Lu, Minxu [Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China); Meng, Yao [Beijing Institute of Aeronautical Materials, Beijing 100095 (China); Zhu, Jinyang; Zhang, Lei [Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China)

    2014-09-30

    Highlights: • The corrosion behavior of 13Cr steel exposed to bromine salt completion fluid containing high concentration bromine ions was investigated. • There are passive circles around pits on the 13Cr steel surface after 7 d of exposure. • Macroscopic galvanic corrosion formed between the passive halo and the pit. • The mechanism of pitting corrosion on 13Cr stainless steel exposed to heavy bromine brine was established. - Abstract: A series of corrosion tests of 13Cr stainless steel were conducted in a simulated completion fluid environment of high temperature and high concentration bromine salt. Corrosion behavior of specimens and the component of corrosion products were investigated by means of scanning electron microscope (SEM), confocal laser scanning microscopy (CLSM) and X-ray photoelectron spectroscopy (XPS). The results indicate that 13Cr steel suffers from severe local corrosion and there is always a passive halo around every pit. The formation mechanism of the passive halo is established. OH{sup −} ligand generates and adsorbs in a certain scale because of abundant OH{sup −} on the surface around the pits. Passive film forms around each pit, which leads to the occurrence of passivation in a certain region. Finally, the dissimilarities in properties and morphologies of regions, namely the pit and its corresponding passive halo, can result in different corrosion sensitivities and may promote the formation of macroscopic galvanic pairs.

  2. Exposure to brominated trihalomethanes in water during pregnancy and micronuclei frequency in maternal and cord blood lymphocytes

    DEFF Research Database (Denmark)

    Stayner, Leslie Thomas; Pedersen, Marie; Patelarou, Evridiki;

    2014-01-01

    BACKGROUND: Water disinfection by-products have been associated with an increased cancer risk. Micronuclei (MN) frequency in lymphocytes is a marker of genomic damage and can predict adult cancer risk. OBJECTIVE: We evaluated maternal exposure to drinking water brominated trihalomethanes (BTHM) i...

  3. Preparation of bromine-77 labelled monoclonal anti-hPLAP [human placental alkaline phosphatase] antibody using chloramine-T

    International Nuclear Information System (INIS)

    A tumor-associated monoclonal antibody, named 7E8 and raised against human placental alkaline phosphatase (hPLAP), is labelled with bromine-77 by means of chloramine-T. The paper describes optimum radiobromination conditions resulting in 34 % radiochemical yield of labelled antibody with more than 90 % immunoreactivity. (author)

  4. Prenatal Exposure to Organohalogens, Including Brominated Flame Retardants, Influences Motor, Cognitive, and Behavioral Performance at School Age

    NARCIS (Netherlands)

    Roze, Elise; Meijer, Lisethe; Bakker, Attie; Van Braeckel, Koenraad N. J. A.; Sauer, Pieter J. J.; Bos, Arend F.

    2009-01-01

    BACKGROUND: Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain. OBJECTIVE: We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age. METHOD

  5. 28 CFR 79.57 - Proof of chronic renal disease.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of chronic renal disease. 79.57... disease. (a) In determining whether a claimant developed chronic renal disease following pertinent... conclusion that a claimant developed chronic renal disease must be supported by medical documentation. (b)...

  6. 28 CFR 79.67 - Proof of chronic renal disease.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of chronic renal disease. 79.67... renal disease. (a) In determining whether a claimant developed chronic renal disease following pertinent... claimant. A conclusion that a claimant developed chronic renal disease must be supported by...

  7. The Ph.D. Job Market: 1978-79.

    Science.gov (United States)

    Kirschner, Ann G.

    1980-01-01

    Among the results of a study of the employment of the 955 English doctorate recipients in 1978-79 were that 60 percent found full-time teaching positions, although only 46 percent of males and 35 percent of females received full-time, tenure-track positions; 12 percent found part-time teaching appointments or postdoctoral fellowships; and 16…

  8. 28 CFR 79.71 - Filing of claims.

    Science.gov (United States)

    2010-07-01

    ... are eligible to file claims for compensation under the Act in the following order: (1) The claimant... the claimant must be established by submitting a birth certificate or one of the other documents identified in § 79.14(a) when the person has no birth certificate. Additionally, documentation...

  9. 28 CFR 79.45 - Proof of primary lung cancer.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of primary lung cancer. 79.45... cancer. (a) In determining whether a claimant developed primary lung cancer following pertinent... conclusion that a claimant developed primary lung cancer must be supported by medical documentation. To...

  10. 28 CFR 79.54 - Proof of primary lung cancer.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of primary lung cancer. 79.54... cancer. (a) In determining whether a claimant developed primary lung cancer following pertinent... conclusion that a claimant developed primary lung cancer must be supported by medical documentation. To...

  11. 28 CFR 79.64 - Proof of primary lung cancer.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of primary lung cancer. 79.64... cancer. (a) In determining whether a claimant developed primary lung cancer following pertinent... claimant. A conclusion that a claimant developed primary lung cancer must be supported by...

  12. 40 CFR 86.344-79 - Humidity calculations.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Humidity calculations. 86.344-79... Humidity calculations. (a) The following abbreviations (and units) are used in this section: BARO = barometric pressure (Pa) H = specific humidity, (gm H2O/gm of dry air) K = 0.6220 gm H2O/gm dry air M...

  13. 44 CFR 7.9 - Assurances from institutions.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Assurances from institutions...) Nondiscrimination in FEMA-Assisted Programs-General § 7.9 Assurances from institutions. (a) In the case of any application for Federal financial assistance to an institution of higher education, the assurance required...

  14. 44 CFR 79.4 - Availability of funding.

    Science.gov (United States)

    2010-10-01

    ... § 79.4 Availability of funding. (a) Allocation. (1) For the amount made available for the SRL program... applicants that have at least 1 SRL property and that receive little or no allocation. (2) For the amount... planning grants nationally. A planning grant will not be awarded to a State or community more than...

  15. Decrease in collectivity at high spins in 79Rb nucleus

    International Nuclear Information System (INIS)

    The life time for the +ve and -ve parity πg9/2 πp3/2 bands in 79Rb were measured by the Doppler Shift Attenuation Methods (DSAM) to investigate nuclear collectivity as a function of rotational frequency

  16. Does College Education Pay? Evidence from the NLSY-79 Data

    Science.gov (United States)

    Afxentiou, Diamando; Kutasovic, Paul

    2010-01-01

    This study examines if the college wage premium favoring college graduates still exists. The NLSY-79 data is employed. The sample includes individuals who received their high school degree and college degree in 1980 and 1981. These individuals were followed until the year 2004. A cross sectional regression model was estimated for the years 1982,…

  17. Economic Analysis. Volume V. Course Segments 65-79.

    Science.gov (United States)

    Sterling Inst., Washington, DC. Educational Technology Center.

    The fifth volume of the multimedia, individualized course in economic analysis produced for the United States Naval Academy covers segments 65-79 of the course. Included in the volume are discussions of monopoly markets, monopolistic competition, oligopoly markets, and the theory of factor demand and supply. Other segments of the course, the…

  18. 40 CFR 86.331-79 - Hydrocarbon analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Hydrocarbon analyzer calibration. 86....331-79 Hydrocarbon analyzer calibration. The following steps are followed in sequence to calibrate the hydrocarbon analyzer. It is suggested, but not required, that efforts be made to minimize relative...

  19. 40 CFR 86.317-79 - Hydrocarbon analyzer specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Hydrocarbon analyzer specifications....317-79 Hydrocarbon analyzer specifications. (a) Hydrocarbon measurements are to be made with a heated... measures hydrocarbon emissions on a dry basis is permitted for gasoline-fueled testing; Provided,...

  20. 40 CFR 79.67 - Glial fibrillary acidic protein assay.

    Science.gov (United States)

    2010-07-01

    ... addition to information meeting the requirements stated under 40 CFR 79.60, the following specific... use rocking or orbital shakers. Perform the following steps in enough solution to cover the nitrocellulose sheets to a depth of 1 cm. (A) Incubate 20 minutes in fixer (25 percent (v/v) isopropanol,...

  1. 9 CFR 3.79 - Mobile or traveling housing facilities.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Mobile or traveling housing facilities... Transportation of Nonhuman Primates 2 Facilities and Operating Standards § 3.79 Mobile or traveling housing facilities. (a) Heating, cooling, and temperature. Mobile or traveling housing facilities must...

  2. 28 CFR 79.16 - Proof of medical condition.

    Science.gov (United States)

    2010-07-01

    ... COMPENSATION ACT Eligibility Criteria for Claims Relating to Leukemia § 79.16 Proof of medical condition. (a... contain a verified diagnosis of leukemia, the Radiation Exposure Compensation Program will notify the...) Autopsy report; (iv) Hospital discharge summary; (v) Physician summary report; (vi) History and...

  3. 42 CFR 84.79 - Breathing gas; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51....S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American National Standards Institute... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing gas; minimum requirements. 84.79...

  4. 40 CFR 761.79 - Decontamination standards and procedures.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Decontamination standards and..., AND USE PROHIBITIONS Storage and Disposal § 761.79 Decontamination standards and procedures. (a) Applicability. This section establishes decontamination standards and procedures for removing PCBs, which...

  5. 40 CFR 79.64 - In vivo micronucleus assay.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Testing Requirements for Registration § 79.64 In vivo... information on this test guideline, the following references should be consulted. (1) 40 CFR 798.5395, In Vivo... 40 Protection of Environment 16 2010-07-01 2010-07-01 false In vivo micronucleus assay....

  6. 40 CFR 79.63 - Fertility assessment/teratology.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Testing Requirements for Registration § 79.63 Fertility assessment/teratology. (a) Purpose. Fertility assessment/teratology is an in vivo study designed to provide... vehicle/engine emissions before and during her pregnancy. By including a mating of test animals, the...

  7. 40 CFR 86.327-79 - Quench checks; NOX analyzer.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Quench checks; NOX analyzer. 86.327-79... Quench checks; NOX analyzer. (a) Perform the reaction chamber quench check for each model of high vacuum... capillary, and if used, dilution capillary. (c) Quench check as follows: (1) Calibrate the NOX analyzer...

  8. Investigating the lifetime of bromine-quenched G.M. Counters with temperature

    International Nuclear Information System (INIS)

    The amount of halogen quench gas as a percentage of the total fill gas contained within a gas-filled Geiger–Müller detector is directly linked to its operational characteristics. Preserving this halogen gas will help maintain the operating lifetime of the detectors. Such halogen gases are highly corrosive and the small quantities within a gas-filled detector can deplete rapidly via interactions with surrounding materials. The rate of interactions is thought to be proportional to not only temperature, but also to the current initiated by ionisation events associated with the formation of each signal pulse. As all pulses are of similar magnitudes, GM detector operational lifetimes are quantified in accumulated counts rather than a given operating time. We have studied three different types of corrosion-resistant mechanisms to protect the bromine halogen gas from any interactions with 446 stainless steel detector components of ZP1200 Geiger–Müller tubes at temperatures up to 125 °C. Three types of surface treatments for these detectors used were labelled as “raw” using only an oxygen-plasma-bombardment process, “passivated” using a combination of nitric acid passivation followed by an oxygen plasma-bombardment process, and thirdly plating with a few micron thickness of chromium followed by an oxygen plasma-bombardment process. 32 detector samples were irradiated at room temperature with a Caesium-137 source at dose rates of approximately 1.3 mSv/hr up to 5.7×1010 accumulated counts; another 32 detector samples were aged to 3.3×1010 counts at 125 °C. At room temperature, the chromium-plated samples exhibited an initial rise in their starting voltage readings. All other detector performance characteristics, for all detector types, did not change significantly during the ageing process, and the surface morphology of the detector cathodes was unaffected. At 125 °C, the chromium-based plating produced the most stable long-term response. These chromium

  9. Mercury oxidation from bromine chemistry in the free troposphere over the southeastern US

    Directory of Open Access Journals (Sweden)

    S. Coburn

    2015-10-01

    Full Text Available The elevated deposition of atmospheric mercury over the Southeastern United States is currently not well understood. Here we measure partial columns and vertical profiles of bromine monoxide (BrO radicals, a key component of mercury oxidation chemistry, to better understand the processes and altitudes at which mercury is being oxidized in the atmosphere. We use the data from a ground-based MAX-DOAS instrument located at a coastal site ~ 1 km from the Gulf of Mexico in Gulf Breeze, FL, where we had previously detected tropospheric BrO (Coburn et al., 2011. Our profile retrieval assimilates information about stratospheric BrO from the WACCM chemical transport model, and uses only measurements at moderately low solar zenith angles (SZA to estimate the BrO slant column density contained in the reference spectrum (SCDRef. The approach has 2.6 degrees of freedom, and avoids spectroscopic complications that arise at high SZA; knowledge about SCDRef helps to maximize sensitivity in the free troposphere (FT. A cloud-free case study day with low aerosol load (9 April 2010 provided optimal conditions for distinguishing marine boundary layer (MBL: 0–1 km and free tropospheric (FT: 1–15 km BrO from the ground. The average daytime tropospheric BrO vertical column density (VCD of ~ 2.3 × 1013 molec cm−2 (SZA 5 molec cm−2 s−1 for bromine, while contributions from ozone (O3 and chlorine (Cl were 0.9 × 105 and 0.2 × 105 molec cm−2 s−1, respectively. The GOM formation rate is sensitive to recently proposed atmospheric scavenging reactions of the HgBr adduct by nitrogen dioxide (NO2, and to a lesser extent also HO2 radicals. Using a 3-D chemical transport model, we find that surface GOM variations are typical also of other days, and are mainly derived from the free troposphere. Bromine chemistry is active in the FT over Gulf Breeze, where it forms water-soluble GOM that is subsequently available for wet scavenging by thunderstorms or transport to

  10. Bromine release during Plinian eruptions along the Central American Volcanic Arc

    Science.gov (United States)

    Hansteen, T. H.; Kutterolf, S.; Appel, K.; Freundt, A.; Perez-Fernandez, W.; Wehrmann, H.

    2010-12-01

    Volcanoes of the Central American Volcanic Arc (CAVA) have produced at least 72 highly explosive eruptions within the last 200 ka. The eruption columns of all these “Plinian” eruptions reached well into the stratosphere such that their released volatiles may have influenced atmospheric chemistry and climate. While previous research has focussed on the sulfur and chlorine emissions during such large eruptions, we here present measurements of the heavy halogen bromine by means of synchrotron radiation induced micro-XRF microanalysis (SR-XRF) with typical detection limits at 0.3 ppm (in Fe rich standard basalt ML3B glass). Spot analyses of pre-eruptive glass inclusions trapped in minerals formed in magma reservoirs were compared with those in matrix glasses of the tephras, which represent the post-eruptive, degassed concentrations. The concentration difference between inclusions and matrix glasses, multiplied by erupted magma mass determined by extensive field mapping, yields estimates of the degassed mass of bromine. Br is probably hundreds of times more effective in destroying ozone than Cl, and can accumulate in the stratosphere over significant time scales. Melt inclusions representing deposits of 22 large eruptions along the CAVA have Br contents between 0.5 and 13 ppm. Br concentrations in matrix glasses are nearly constant at 0.4 to 1.5 ppm. However, Br concentrations and Cl/Br ratios vary along the CAVA. The highest values of Br contents (>8 ppm) and lowest Cl/Br ratios (170 to 600) in melt inclusions occur across central Nicaragua and southern El Salvador, and correlate with bulk-rock compositions of high Ba/La > 85 as well as low La/Yb discharged 700 kilotons of Br. On average, each of the remaining 21 CAVA eruptions studied have discharged c.100 kilotons of bromine. During the past 200 ka, CAVA volcanoes have emitted a cumulative mass of 3.2 Mt of Br through highly explosive eruptions. There are six periods in the past (c. 2ka, 6ka, 25ka, 40ka, 60ka, 75

  11. Mercury oxidation from bromine chemistry in the free troposphere over the southeastern US

    Science.gov (United States)

    Coburn, Sean; Dix, Barbara; Edgerton, Eric; Holmes, Christopher D.; Kinnison, Douglas; Liang, Qing; ter Schure, Arnout; Wang, Siyuan; Volkamer, Rainer

    2016-03-01

    The elevated deposition of atmospheric mercury over the southeastern United States is currently not well understood. Here we measure partial columns and vertical profiles of bromine monoxide (BrO) radicals, a key component of mercury oxidation chemistry, to better understand the processes and altitudes at which mercury is being oxidized in the atmosphere. We use data from a ground-based MAX-DOAS instrument located at a coastal site ˜ 1 km from the Gulf of Mexico in Gulf Breeze, FL, where we had previously detected tropospheric BrO (Coburn et al., 2011). Our profile retrieval assimilates information about stratospheric BrO from the WACCM chemical transport model (CTM), and uses only measurements at moderately low solar zenith angles (SZAs) to estimate the BrO slant column density contained in the reference spectrum (SCDRef). The approach has 2.6 degrees of freedom, and avoids spectroscopic complications that arise at high SZA; knowledge about SCDRef further helps to maximize sensitivity in the free troposphere (FT). A cloud-free case study day with low aerosol load (9 April 2010) provided optimal conditions for distinguishing marine boundary layer (MBL: 0-1 km) and free-tropospheric (FT: 1-15 km) BrO from the ground. The average daytime tropospheric BrO vertical column density (VCD) of ˜ 2.3 × 1013 molec cm-2 (SZA vertical profile locates essentially all tropospheric BrO above 4 km, and shows no evidence for BrO inside the MBL (detection limit rates are about 3.6 × 105 molec cm-2 s-1 for bromine, while the contribution from ozone (O3) is 0.8 × 105 molec cm-2 s-1. Chlorine-induced oxidation is estimated to add rates. The GOM formation rate is sensitive to recently proposed atmospheric scavenging reactions of the HgBr adduct by nitrogen dioxide (NO2), and to a lesser extent also HO2 radicals. Using a 3-D CTM, we find that surface GOM variations are also typical of other days, and are mainly derived from the FT. Bromine chemistry is active in the FT over Gulf

  12. Investigating the lifetime of bromine-quenched G.M. Counters with temperature

    Science.gov (United States)

    Abilama, Marc; Bates, Mike; Lohstroh, Annika

    2015-09-01

    The amount of halogen quench gas as a percentage of the total fill gas contained within a gas-filled Geiger-Müller detector is directly linked to its operational characteristics. Preserving this halogen gas will help maintain the operating lifetime of the detectors. Such halogen gases are highly corrosive and the small quantities within a gas-filled detector can deplete rapidly via interactions with surrounding materials. The rate of interactions is thought to be proportional to not only temperature, but also to the current initiated by ionisation events associated with the formation of each signal pulse. As all pulses are of similar magnitudes, GM detector operational lifetimes are quantified in accumulated counts rather than a given operating time. We have studied three different types of corrosion-resistant mechanisms to protect the bromine halogen gas from any interactions with 446 stainless steel detector components of ZP1200 Geiger-Müller tubes at temperatures up to 125 °C. Three types of surface treatments for these detectors used were labelled as "raw" using only an oxygen-plasma-bombardment process, "passivated" using a combination of nitric acid passivation followed by an oxygen plasma-bombardment process, and thirdly plating with a few micron thickness of chromium followed by an oxygen plasma-bombardment process. 32 detector samples were irradiated at room temperature with a Caesium-137 source at dose rates of approximately 1.3 mSv/hr up to 5.7×1010 accumulated counts; another 32 detector samples were aged to 3.3×1010 counts at 125 °C. At room temperature, the chromium-plated samples exhibited an initial rise in their starting voltage readings. All other detector performance characteristics, for all detector types, did not change significantly during the ageing process, and the surface morphology of the detector cathodes was unaffected. At 125 °C, the chromium-based plating produced the most stable long-term response. These chromium-plated samples

  13. Molecular simulations and density functional theory calculations of bromine in clathrate hydrate phases

    Energy Technology Data Exchange (ETDEWEB)

    Dureckova, Hana, E-mail: houci059@uottawa.ca; Woo, Tom K., E-mail: tom.woo@uottawa.ca [Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 5N6 (Canada); Alavi, Saman, E-mail: saman.alavi@nrc-cnrc.gc.ca [Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 5N6 (Canada); National Research Council of Canada, 100 Sussex Dr., Ottawa, Ontario K1N 6N5 (Canada); Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, British Columbia V6T 1Z3 (Canada)

    2016-01-28

    Bromine forms a tetragonal clathrate hydrate structure (TS-I) very rarely observed in clathrate hydrates of other guest substances. The detailed structure, energetics, and dynamics of Br{sub 2} and Cl{sub 2} in TS-I and cubic structure I (CS-I) clathrate hydrates are studied in this work using molecular dynamics and quantum chemical calculations. X-ray diffraction studies show that the halogen-water–oxygen distances in the cages of these structures are shorter than the sum of the van der Waals radii of halogen and oxygen atoms. This suggests that the stabilizing effects of halogen bonding or other non-covalent interactions (NCIs) may contribute to the formation of the unique tetragonal bromine hydrate structure. We performed molecular dynamics simulations of Br{sub 2} and Cl{sub 2} clathrate hydrates using our previously developed five-site charge models for the dihalogen molecules [Dureckova et al. Can. J. Chem. 93, 864 (2015)] which reproduce the computed electrostatic potentials of the dihalogens and account for the electropositive σ-hole of the halogen bond donor (the dihalogen). Analysis of the radial distribution functions, enthalpies of encapsulation, velocity and orientation autocorrelation functions, and polar angle distributions are carried out for Br{sub 2} and Cl{sub 2} guests in various cages to contrast the properties of these guests in the TS-I and CS-I phases. Quantum chemical partial geometry optimizations of Br{sub 2} and Cl{sub 2} guests in the hydrate cages using the M06-2X functional give short halogen-water distances compatible with values observed in X-ray diffraction experiments. NCI plots of guest-cage structures are generated to qualitatively show the relative strength of the non-bonding interactions between dihalogens and water molecules. The differences between behaviors of Br{sub 2} and Cl{sub 2} guests in the hydrate cages may explain why bromine forms the unique TS-I phase.

  14. Investigating the lifetime of bromine-quenched G.M. Counters with temperature

    Energy Technology Data Exchange (ETDEWEB)

    Abilama, Marc [Centronic Ltd., Croydon (United Kingdom); University of Surrey, Guildford (United Kingdom); Bates, Mike [Centronic Ltd., Croydon (United Kingdom); Lohstroh, Annika [University of Surrey, Guildford (United Kingdom)

    2015-09-21

    The amount of halogen quench gas as a percentage of the total fill gas contained within a gas-filled Geiger–Müller detector is directly linked to its operational characteristics. Preserving this halogen gas will help maintain the operating lifetime of the detectors. Such halogen gases are highly corrosive and the small quantities within a gas-filled detector can deplete rapidly via interactions with surrounding materials. The rate of interactions is thought to be proportional to not only temperature, but also to the current initiated by ionisation events associated with the formation of each signal pulse. As all pulses are of similar magnitudes, GM detector operational lifetimes are quantified in accumulated counts rather than a given operating time. We have studied three different types of corrosion-resistant mechanisms to protect the bromine halogen gas from any interactions with 446 stainless steel detector components of ZP1200 Geiger–Müller tubes at temperatures up to 125 °C. Three types of surface treatments for these detectors used were labelled as “raw” using only an oxygen-plasma-bombardment process, “passivated” using a combination of nitric acid passivation followed by an oxygen plasma-bombardment process, and thirdly plating with a few micron thickness of chromium followed by an oxygen plasma-bombardment process. 32 detector samples were irradiated at room temperature with a Caesium-137 source at dose rates of approximately 1.3 mSv/hr up to 5.7×10{sup 10} accumulated counts; another 32 detector samples were aged to 3.3×10{sup 10} counts at 125 °C. At room temperature, the chromium-plated samples exhibited an initial rise in their starting voltage readings. All other detector performance characteristics, for all detector types, did not change significantly during the ageing process, and the surface morphology of the detector cathodes was unaffected. At 125 °C, the chromium-based plating produced the most stable long-term response. These

  15. Nuclear-spectroscopic measurements related to the design of 79Br, 81Br, and 87Rb solar-neutrino detectors

    International Nuclear Information System (INIS)

    Spectroscopic properties for low-lying states in 79Kr, 81Kr, and 87Sr were studied using the 78Kr(dvector,p)79Kr, 80Kr(dvector,p)81Kr, and 86Sr(dvector,p)87Sr reactions initiated by 11 MeV purely vector-polarized deuteron beams at Triangle Universities Nuclear Laboratory. A Distorted-Wave Born Approximation analysis of the resulting angular distributions of cross section and vector analyzing power enabled the assignment of spin-parity and extraction of neutron spectroscopic factors for 48 nuclear states. A technique for preparation of thin targets using ion implantation was developed as a means to improve spectrum resolution by reducing projectile straggling in the entrance and exit foils of gas cell targets. The neutrino capture process, sigma + (Z,A) → (Z + 1,A) + e-, is equivalent to inverse beta decay. In order to interpret the results of a solar neutrino experiment using 79Br, 81Br, or 87Rb, low-lying states in the daughter nuclei, 79Kr, 81Kr, and 87Sr, must be studied. In particular, the states in the daughter nuclei that have appropriate spin-parity to be populated by allowed inverse beta decay must be identified

  16. Air-snowpack exchange of bromine, ozone and mercury in the springtime Arctic simulated by the 1-D model PHANTAS – Part 1: In-snow bromine activation and its impact on ozone

    Directory of Open Access Journals (Sweden)

    K. Toyota

    2013-08-01

    Full Text Available To provide a theoretical framework towards better understanding of ozone depletion events (ODEs and atmospheric mercury depletion events (AMDEs in the polar boundary layer, we have developed a one-dimensional model that simulates multiphase chemistry and transport of trace constituents from porous snowpack and through the atmospheric boundary layer (ABL as a unified system. In this paper, we describe a general configuration of the model and the results of simulations related to reactive bromine release from the snowpack and ODEs during the Arctic spring. The model employs a chemical mechanism adapted from the one previously used for the simulation of multiphase halogen chemistry involving deliquesced sea-salt aerosols in the marine boundary layer. A common set of aqueous-phase reactions describe chemistry both in the liquid-like (or brine layer on the grain surface of the snowpack and in "haze" aerosols mainly composed of sulfate in the atmosphere. The process of highly soluble/reactive trace gases, whether entering the snowpack from the atmosphere or formed via gas-phase chemistry in the snowpack interstitial air (SIA, is simulated by the uptake on brine-covered snow grains and subsequent reactions in the aqueous phase while being traveled vertically within the SIA. A "bromine explosion", by which, in a conventional definition, HOBr formed in the ambient air is deposited and then converted heterogeneously to Br2, is a dominant process of reactive bromine formation in the top 1 mm (or less layer of the snowpack. Deeper in the snowpack, HOBr formed within the SIA leads to an in-snow bromine explosion, but a significant fraction of Br2 is also produced via aqueous radical chemistry in the brine on the surface of the snow grains. These top- and deeper-layer productions of Br2 both contribute to the Br2 release into the atmosphere, but the deeper-layer production is found to be more important for the net outflux of reactive bromine. Although ozone

  17. Optimization and Simultaneous Determination of Alkyl Phenol Ethoxylates and Brominated Flame Retardants in Water after SPE and Heptafluorobutyric Anhydride Derivatization followed by GC/MS.

    Science.gov (United States)

    Chokwe, Tlou B; Okonkwo, Jonathan O; Sibali, Linda L; Ncube, Esper J

    2012-10-01

    A gas chromatography-mass spectrometry (GC-MS) method was investigated for the simultaneous analysis of two types of endocrine disrupting compounds (EDCs), i.e., alkylphenol ethoxylates and brominated flame retardants (BFRs), by extraction and derivatization followed by GC-MS. Different solid phase extraction (SPE) cartridges (Cleanert PestiCarb, C18, Cleanert-SAX and Florosil), solvents (toluene, tetrahydrofuran, acetone, acetonitrile and ethyl acetate) and bases (NaHCO3, triethylamine and pyridine) were tested and the best chromatographic analysis was achieved by extraction with Strata-X (33 μm, Reverse Phase) cartridge and derivatization with heptafluorobutyric anhydride at 55 °C under Na2CO3 base in hexane. It was observed that APE together with lower substituted PBBs (PBB1, PBB10, PBB18 and PBB49), HBCD and TBBPA can be determined simultaneously under the same GC conditions. This simple and reliable analytical method was applied to determining trace amounts of these compounds from wastewater treatment plant samples. The recoveries of the target compounds from simulated water were above 60 %. The limit of detection ranged from 0.01 to 0.15 μg L(-1) and the limit of quantification ranged from 0.05 to 0.66 μg L(-1). There were no appreciable differences between filtered and unfiltered wastewater samples from Leeuwkil treatment plant although concentration of target analytes in filtered influent was slightly lower than the concentration of target analytes in unfiltered influent water. The concentrations of the target compounds from the wastewater treatment were determined from LOQ upwards. PMID:23864736

  18. Thinning of CIGS solar cells: Part I: Chemical processing in acidic bromine solutions

    Energy Technology Data Exchange (ETDEWEB)

    Bouttemy, M.; Tran-Van, P. [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France); Gerard, I., E-mail: gerard@chimie.uvsq.fr [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France); Hildebrandt, T.; Causier, A. [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France); Pelouard, J.L.; Dagher, G. [Laboratoire de Photonique et de Nanostructures (LPN-CNRS), route de Nozay 91460 Marcoussis (France); Jehl, Z.; Naghavi, N. [Institut de Recherche et Developpement sur l' Energie Photovoltaique (IRDEP -UMR 7174 CNRS/EDF/Chimie-ParisTech), 6 quai Watier, 78401 Chatou (France); Voorwinden, G.; Dimmler, B. [Wuerth Elektronik Research GmbH, Industriestr. 4, 70565 Stuttgart (Germany); Powalla, M. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung (ZSW), Industriestr. 6, 70565 Stuttgart (Germany); Guillemoles, J.F. [Institut de Recherche et Developpement sur l' Energie Photovoltaique (IRDEP -UMR 7174 CNRS/EDF/Chimie-ParisTech), 6 quai Watier, 78401 Chatou (France); Lincot, D. [Laboratoire de Photonique et de Nanostructures (LPN-CNRS), route de Nozay 91460 Marcoussis (France); Etcheberry, A. [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France)

    2011-08-31

    CIGSe absorber was etched in HBr/Br{sub 2}/H{sub 2}O to prepare defined thicknesses of CIGSe between 2.7 and 0.5 {mu}m. We established a reproducible method of reducing the absorber thickness via chemical etching. We determine the dissolution kinetics rate of CIGSe using trace analysis by graphite furnace atomic absorption spectrometry of Ga and Cu. The roughness of the etching surface decreases during the first 500 nm of the etching to a steady state value of the root-mean-square roughness near 50 nm. X-ray photoelectron spectroscopy analyses demonstrate an etching process occurring with a constant chemical composition of the treated surface acidic bromine solutions provide a controlled chemical thinning process resulting in an almost flat surface and a very low superficial Se{sup 0} enrichment.

  19. Highly sensitive spectrofluorimetric determination of trace amounts of indium with 5-bromine-salicylaldehyde salicyloylhydrazone

    International Nuclear Information System (INIS)

    The fluorescent reaction of 5-bromine-salicylaldehyde salicyloylhydrazone (5-Br-SASH) with indium was studied in detail. Based on this chelating reaction, a sensitive spectrofluorimetric method was developed for the determination of indium in a water-ethanol (37:63) medium at pH 4.6. Under these conditions, the In-5-Br-SASH complex has excitation and emission maximum at 395 nm and 461 nm, respectively. The linear range of the method is from 0 to 1000 ng ml-1 and the detection limit is 2.4 ng ml-1. The molar ratio of indium to the reagent is 1:3. Interferences of other ions were studied. The method was successfully applied to the determination of indium in the chemical reagents such as lead, tin, spelter, zinc sulfide by standard additions method

  20. Labeling of receptor ligands with bromine radionuclides. Progress report, March 1, 1981-February 29, 1984

    International Nuclear Information System (INIS)

    We have developed techniques to label several types of organic molecules with radiobromine. We have emphasized techniques to label ligands for the estrogen receptor and have studied two brominated compounds in rat models. One of these compounds has been studied in a limited number of patients and estrogen containing tumors visualized by nuclear medicine imaging. We have recently expanded the size of the work to label receptor ligands with fluorine-18 and have carried out preliminary animal studies which suggest that a clinically useful compound can be prepared. In addition to the receptor studies, we have collaborated in assessing 77Br-labeled compounds as therapeutic agents and in studying 77Br-labeled compounds using perturbed angular correlation techniques

  1. Responses of marine unicellular algae to brominated organic compounds in six growth media

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, G.E.; Yoder, M.J.; McLaughlin, L.L.; Lores, E.M.

    1987-12-01

    Marine unicellular algae, Skeletonema costatum, Thalassiosira pseudonana, and Chlorella sp. were exposed to the industrial brominated compounds tetrabromobisphenol A, decabromobiphenyloxide (DBBO), hexabromocyclododecane (HBCD), pentabromomethylbenzene (PBMB), pentabromoethylbenzene (PBEB), and the herbicide bromoxynil (BROM), in six algal growth media. High concentrations of DBBO (1 mg liter-1), PBMB (1 mg liter-1), and PBEB (0.5 mg liter-1) reduced growth by less than 50%. EC50s of the other compounds varied with growth medium, with high EC50/low EC50 ratios between 1.3 and 9.9. Lowest EC50s, 9.3 to 12.0 micrograms liter-1, were obtained with S. costatum and HBCD. It is concluded that responses to toxicants in different media are the results of interactions among algae, growth medium, toxicant, and solvent carrier.

  2. Radio- and photo-sensitization of DNA with compounds containing platinum and bromine atoms

    International Nuclear Information System (INIS)

    Irradiations of plasmid DNA by both X-rays and UV light in the presence and absence of compounds containing platinum and bromine atoms, were performed in order to assess the sensitization potential of these compounds. Plasmid DNA pBR322 was incubated with platinum (II) bromide, hydrogen hexabromoplatinate (IV), hydrogen hexahydroxyplatinate (IV) and sodium hexahydroxyplatinate (IV). Incubation was followed by X-ray or UV irradiations. It was found that amongst the sensitizers tested, during irradiations carried out in the presence of platinum (II) bromide, the highest levels of double strand breaks formation upon X-ray treatment were recorded. In contrast much less damage was induced by UV light. Data presented here suggests that this compound may be a promising radiosensitizer for cancer treatment. (authors)

  3. Surface-confined 2D polymerization of a brominated copper-tetraphenylporphyrin on Au(111)

    CERN Document Server

    Smykalla, Lars; Korb, Marcus; Lang, Heinrich; Hietschold, Michael

    2015-01-01

    A coupling-limited approach for the Ullmann reaction-like on-surface synthesis of a two-dimensional covalent organic network starting from a halogenated metallo-porphyrin is demonstrated. Copper-octabromo-tetraphenylporphyrin molecules can diffuse and self-assemble when adsorbed on the inert Au(111) surface. Splitting-off of bromine atoms bonded at the macrocyclic core of the porphyrin starts at room temperature after the deposition and is monitored by X-ray photoelectron spectroscopy for different annealing steps. Direct coupling between the reactive carbon sites of the molecules is, however, hindered by the molecular shape. This leads initially to an ordered non-covalently interconnected supramolecular structure. Further heating to 300{\\deg}C and an additional hydrogen dissociation step is required to link the molecular macrocycles via a phenyl group and form large ordered polymeric networks. This approach leads to a close-packed covalently bonded network of overall good quality. The structures are characte...

  4. Bioactive brominated diterpenes from the marine red alga Jania Rubens (L.) Lamx.

    Science.gov (United States)

    Awad, Nagwa E

    2004-04-01

    Seven brominated diterpenes of the parguerene and isoparguerene series were isolated for the first time from the red alga Jania rubens (L.) Lamx., collected from the Red Sea coast at Hurghada, Egypt. The diterpenes were identified as isoparguerol (1), isoparguerol-16-acetate (2), isoparguerol-7,16-diacetate (3), parguerol-16-acetate (4), parguerol-7,16-diacetate (5), deoxyparguerol (6) and deoxyparguerol-7-acetate (7). The isolated diterpenes had a marked antitumour activity. Isoparguerol derivatives were slightly more effective than parguerol derivatives. Moreover, the data implied that the cytotoxicity of these compounds were dependent on the number of acetoxy groups. Also, anthelmintic activities of the isolated compounds on earthworms (Allolobophora caliginosa) were studied. PMID:15162360

  5. Short-lived brominated hydrocarbons – observations in the source regions and the tropical tropopause layer

    Directory of Open Access Journals (Sweden)

    S. Brinckmann

    2012-02-01

    Full Text Available We conducted measurements of the five important short-lived organic bromine species in the marine boundary layer (MBL. Measurements were made in the Northern Hemisphere mid-latitudes (Sylt Island, North Sea in June 2009 and in the tropical Western Pacific during the TransBrom ship campaign in October 2009. For the one-week time series on Sylt Island, mean mixing ratios of CHBr3, CH2Br2, CHBr2Cl and CH2BrCl were 2.0, 1.1, 0.2, 0.1 ppt, respectively. We found maxima of 5.8 and 1.6 ppt for the two main components CHBr3 and CH2Br2. Along the cruise track in the Western Pacific (between 41° N and 13° S we measured mean mixing ratios of 0.9, 0.9, 0.2, 0.1 and 0.1 ppt for CHBr3, CH2Br2, CHBrCl2, CHBr2Cl and CH2BrCl. Air samples with coastal influence showed considerably higher mixing ratios than the samples with open ocean origin. Correlation analyses of the two data sets yielded strong linear relationships between the mixing ratios of four of the five species (except for CH2BrCl. Using a combined data set from the two campaigns and a comparison with the results from two former studies, rough estimates of the molar emission ratios between the correlated substances were: 9/1/0.35/0.35 for CHBr3/CH2Br2/CHBrCl2/CHBr2Cl. Additional measurements were made in the tropical tropopause layer (TTL above Teresina (Brazil, 5° S in June 2008, using balloon-borne cryogenic whole air sampling technique. Near the level of zero clear-sky net radiative heating (LZRH at 14.8 km about 2.25 ppt organic bromine was bound to the five short-lived species, making up 13% of total organic bromine (17.82 ppt. CH2Br2 (1.45 ppt and CHBr3 (0.56 ppt accounted for 90% of the budget of short-lived compounds in that region. Near the

  6. Resonant x-ray reflectivity from a bromine-labeled fatty acid Langmuir monolayer

    International Nuclear Information System (INIS)

    Resonant x-ray reflectivity exploits the energy dependence of atomic scattering factors to locate resonant atoms within the electron density distribution of thin films. We apply the technique to a monolayer of bromo-stearic acid at the air/water interface. The data collection protocol employed cycles through several energies in the vicinity of the bromine K absorption edge and verifies that the energy dependencies observed are indeed resonant effects. The analysis specifies the location of the Br atom with sub-angstrom precision and must consider both the real and imaginary parts of the changes in the scattering factor to be consistent with the known structure and stoichiometry of this test case

  7. Kinetics and mechanism of the oxidation of some -hydroxy acids by hexamethylenetetramine-bromine

    Indian Academy of Sciences (India)

    Dimple Garg; Seema Kothari

    2004-11-01

    The oxidation of lactic acid, mandelic acid and ten monosubstituted mandelic acids by hexamethylenetetramine-bromine (HABR) in glacial acetic acid, leads to the formation of the corresponding oxoacid. The reaction is first order with respect to each of the hydroxy acids and HABR. It is proposed that HABR itself is the reactive oxidizing species. The oxidation of -deuteriomandelic acid exhibits the presence of a substantial kinetic isotope effect (/ = 5.91 at 298 K). The rates of oxidation of the substituted mandelic acids show excellent correlation with Brown’s + values. The reaction constants are negative. The oxidation exhibits an extensive cross conjugation between the electron-donating substituent and the reaction centre in the transition state. A mechanism involving transfer of a hydride ion from the acid to the oxidant is postulated.

  8. Associations between brominated flame retardants in house dust and hormone levels in men

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Paula I. [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Stapleton, Heather M. [Nicholas School of the Environment, Box 90328, Duke University, Durham, NC 27708 (United States); Mukherjee, Bhramar [Department of Biostatistics, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Hauser, Russ [Department of Environmental Health, Harvard School of Public Health, 677 Huntington Ave., Boston, MA 02115 (United States); Meeker, John D., E-mail: meekerj@umich.edu [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)

    2013-02-15

    Brominated flame retardants (BFRs) are used in the manufacture of a variety of materials and consumer products in order to meet fire safety standards. BFRs may persist in the environment and have been detected in wildlife, humans and indoor dust and air. Some BFRs have demonstrated endocrine and reproductive effects in animals, but human studies are limited. In this exploratory study, we measured serum hormone levels and flame retardant concentrations [31 polybrominated diphenyl ether (PBDE) congeners and 6 alternate flame retardants] in house dust from men recruited through a US infertility clinic. PBDE congeners in dust were grouped by commercial mixtures (i.e. penta-, octa- and deca-BDE). In multivariable linear regression models adjusted by age and body mass index (BMI), significant positive associations were found between house dust concentrations of pentaBDEs and serum levels of free T4, total T3, estradiol, and sex hormone binding globulin (SHBG), along with an inverse association with follicle stimulating hormone (FSH). There were also positive associations of octaBDE concentrations with serum free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH) and testosterone and an inverse association of decaBDE concentrations with testosterone. Hexabromocyclododecane (HBCD) was associated with decreased SHBG and increased free androgen index. Dust concentrations of bis-tribromophenoxyethane (BTBPE) and tetrabromo-diethylhexylphthalate (TBPH) were positively associated with total T3. These findings are consistent with our previous report of associations between PBDEs (BDE 47, 99 and 100) in house dust and hormone levels in men, and further suggest that exposure to contaminants in indoor dust may be leading to endocrine disruption in men. - Highlights: ► Brominated flame retardants (BFRs) including PBDEs and alternates were measured. ► Exposure to BFRs is characterized from concentrations in participant vacuum bag dust. ► Exposure to PBDEs and

  9. Scientific Opinion on Emerging and Novel Brominated Flame Retardants (BFRs in Food

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Contaminants in the Food Chain (CONTAM

    2012-10-01

    Full Text Available EFSA was asked to deliver a scientific opinion on brominated flame retardants (BFRs other than PBDEs, PBBs, HBCDDs, TBBPA and brominated phenols and their derivatives. The BFRs that are the subject of the current opinion, were classified in groups termed ‘emerging’ and ‘novel’ BFRs. Information on 17 emerging and 10 novel BFRs was collected. The information varied widely for these BFRs. There is a lack of experimental data on physico-chemical characteristics, stability/reactivity and current use and production volume of all the emerging and novel BFRs. Due to the very limited information on occurrence, exposure and toxicity, the CONTAM Panel could not perform a risk characterisation for any of the BFRs considered. Instead, an attempt was made to identify those BFRs that could be a potential health concern and should be considered first for future investigations. For this purpose the Panel first evaluated the available experimental data on occurrence in food, behaviour in the environment and toxicity. Secondly, a modelling exercise was performed focussing on the potential of the emerging and novel BFRs for persistence in the environment and for their possible bioaccumulation potential. There is convincing evidence that tris(2,3-dibromopropyl phosphate (TDBPP and dibromoneopentyl glycol (DBNPG are genotoxic and carcinogenic, warranting further surveillance of their occurrence in the environment and in food. Based on the limited experimental data on environmental behaviour, 1,2-bis(2,4,6-tribromophenoxyethane (BTBPE and hexabromobenzene (HBB were identified as compounds that could raise a concern for bioaccumulation. For the modelling exercise, the CONTAM Panel selected two environmental characteristics, overall persistence and potential for bioaccumulation, as being most relevant to provide insight into the possibility that emerging or novel BFRs might accumulate in the food chain, and thus might appear in food intended for human

  10. Determination of chlorine, fluorine, bromine, and iodine in coals with ICP-MS and IC

    Energy Technology Data Exchange (ETDEWEB)

    Bettinelli, M.; Spezia, S.; Minoia, C.; Ronchi, A. [Salvatore Maugeri Foundation, Pavia (Italy)

    2002-07-01

    The combustion process releases many organic and inorganic pollutants into the atmosphere, both in gaseous and solid form. During coal combustion in thermal power plants without pollution control equipment, chlorine, fluorine, bromine, and iodine present in coals are mainly volatilized as gaseous compounds. Limiting pollutant emissions is a precise requirement of the Italian legislation that fixes (in the case of power plants) 100 mg/Nm{sup 3} as the limit value for chlorine, and 5 mg/Nm{sup 3} for fluorine and bromine (expressed as hydrofluoric and hydrobromic acid respectively). No limit for iodine emissions has been established. From this point of view and in order to maintain control of emissions from combustion plants, it is important to monitor the concentration of halogens in fuels. Unfortunately, in literature there are very few data published with regard to the amount of halogens in fossil fuels, which emphasizes the analytical difficulties with regard to the determination of these analytes. In the present paper a, pyrohydrolysis of the sample at 1100{degree}C, followed by the absorption of volatilized compounds in Na{sub 2}CO{sub 3}/NaHCO{sub 3} solution and the final instrumental analysis of Cl, Br, and F with ion chromatography (IC) and Br and I with inductively coupled plasma mass spectrometry (ICP-MS) has been adopted. The accuracy of the method, evaluated by analyzing some certified reference materials, was better than 95% for all analytes and the detection limits adequate to the analytical requirements (0.1 mg/kg for Br and I, 1 mg/kg for F, and 10 mg/kg for C1).

  11. Meteorological controls on the vertical distribution of bromine monoxide in the lower troposphere

    Directory of Open Access Journals (Sweden)

    P. K. Peterson

    2014-09-01

    Full Text Available Multiple axis differential absorption spectroscopy (MAX-DOAS measurements of bromine monoxide (BrO probed the vertical structure of halogen activation events during March–May 2012 at Barrow, Alaska. An analysis of the BrO averaging kernels and degrees of freedom obtained by optimal-estimation-based inversions from raw MAX-DOAS measurements reveals the information is best represented by reducing the retrieved BrO profile to two quantities, the integrated column from the surface through 200 m (VCD200 m, and the lower tropospheric vertical column density (LT-VCD which represents the integrated column of BrO from the surface through 2 km. The percentage of lower-tropospheric BrO in the lowest 200 m was found to be highly variable ranging from shallow layer events, where BrO is present primarily in the lowest 200 m to distributed column events where BrO is observed at higher altitudes. The highest observed LT-VCD events occurred when BrO was distributed throughout the lower troposphere, rather than concentrated near the surface. Atmospheric stability in the lowest 200 m influenced the percentage of LT-VCD that is in the lowest 200 m, with inverted temperature structures having a first-to-third quartile range (Q1–Q3 of VCD200 m/LT-VCD from 15–39% while near neutral temperature structures had a Q1–Q3 range of 7–13%. Data from this campaign show no clear influence of wind speed on either lower-tropospheric bromine activation (LT-VCD or the vertical distribution of BrO, while examination of seasonal trends and the temperature dependence of the vertical distribution supported the conclusion that the atmospheric stability affects the vertical distribution of BrO.

  12. UTILIZATION OF BROMINATION REACTION FOR THE SPECTROPHOTOMETRIC ASSAY OF DOMPERIDONE IN PHARMACEUTICALS

    Directory of Open Access Journals (Sweden)

    O. ZENITA DEVI

    2011-03-01

    Full Text Available Three simple and sensitive spectrophotometric methods are described for the determination of domperidone (DOM in bulk drug and in dosage forms using bromate-bromide mixture as brominating agent in acid medium and three dyes, meta-cresol purple (MCP, amaranth (AMR and erioglaucine (EGC. The methods involve the addition of a known excess of bromate-bromide mixture to an acidified solution of DOM followed by the determination of the residual bromine by reacting with a fixed amount of either MCP dye and measuring the absorbance at 530 nm (method A or AMR dye and measuring the absorbance at 520 nm (method B or EGC dye and measuring the absorbance at 630 nm (method C. Beer’s law is obeyed over the concentration ranges, 0.63–10.0, 0.25-4.0 and 0.13-2.0 µg mL-1 for method A, B and C, respectively. The ap¬parent molar absorptivities are calculated to be 3.751x104, 6.604x104 and 1.987x105 L mol-1cm-1 for method A, B and C, respectively, and the corresponding sandell sensitivity values are 0.011, 0.006 and 0.002 μg cm-2. The limit of detection and the limit of quantification are also reported for all the three methods. No interference was observed from common additives found in pharmaceutical preparations. Statistical comparisons of the results with those of the reference method showed excellent agreement, and indicated no significant difference in accuracy and precision. The accuracy and reliability of the methods were further ascertained by performing recovery tests via standardaddition technique.

  13. Associations between brominated flame retardants in house dust and hormone levels in men

    International Nuclear Information System (INIS)

    Brominated flame retardants (BFRs) are used in the manufacture of a variety of materials and consumer products in order to meet fire safety standards. BFRs may persist in the environment and have been detected in wildlife, humans and indoor dust and air. Some BFRs have demonstrated endocrine and reproductive effects in animals, but human studies are limited. In this exploratory study, we measured serum hormone levels and flame retardant concentrations [31 polybrominated diphenyl ether (PBDE) congeners and 6 alternate flame retardants] in house dust from men recruited through a US infertility clinic. PBDE congeners in dust were grouped by commercial mixtures (i.e. penta-, octa- and deca-BDE). In multivariable linear regression models adjusted by age and body mass index (BMI), significant positive associations were found between house dust concentrations of pentaBDEs and serum levels of free T4, total T3, estradiol, and sex hormone binding globulin (SHBG), along with an inverse association with follicle stimulating hormone (FSH). There were also positive associations of octaBDE concentrations with serum free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH) and testosterone and an inverse association of decaBDE concentrations with testosterone. Hexabromocyclododecane (HBCD) was associated with decreased SHBG and increased free androgen index. Dust concentrations of bis-tribromophenoxyethane (BTBPE) and tetrabromo-diethylhexylphthalate (TBPH) were positively associated with total T3. These findings are consistent with our previous report of associations between PBDEs (BDE 47, 99 and 100) in house dust and hormone levels in men, and further suggest that exposure to contaminants in indoor dust may be leading to endocrine disruption in men. - Highlights: ► Brominated flame retardants (BFRs) including PBDEs and alternates were measured. ► Exposure to BFRs is characterized from concentrations in participant vacuum bag dust. ► Exposure to PBDEs and

  14. Meteorological controls on the vertical distribution of bromine monoxide in the lower troposphere

    Science.gov (United States)

    Peterson, P. K.; Simpson, W. R.; Pratt, K. A.; Shepson, P. B.; Frieß, U.; Zielcke, J.; Platt, U.; Walsh, S. J.; Nghiem, S. V.

    2014-09-01

    Multiple axis differential absorption spectroscopy (MAX-DOAS) measurements of bromine monoxide (BrO) probed the vertical structure of halogen activation events during March-May 2012 at Barrow, Alaska. An analysis of the BrO averaging kernels and degrees of freedom obtained by optimal-estimation-based inversions from raw MAX-DOAS measurements reveals the information is best represented by reducing the retrieved BrO profile to two quantities, the integrated column from the surface through 200 m (VCD200 m), and the lower tropospheric vertical column density (LT-VCD) which represents the integrated column of BrO from the surface through 2 km. The percentage of lower-tropospheric BrO in the lowest 200 m was found to be highly variable ranging from shallow layer events, where BrO is present primarily in the lowest 200 m to distributed column events where BrO is observed at higher altitudes. The highest observed LT-VCD events occurred when BrO was distributed throughout the lower troposphere, rather than concentrated near the surface. Atmospheric stability in the lowest 200 m influenced the percentage of LT-VCD that is in the lowest 200 m, with inverted temperature structures having a first-to-third quartile range (Q1-Q3) of VCD200 m/LT-VCD from 15-39% while near neutral temperature structures had a Q1-Q3 range of 7-13%. Data from this campaign show no clear influence of wind speed on either lower-tropospheric bromine activation (LT-VCD) or the vertical distribution of BrO, while examination of seasonal trends and the temperature dependence of the vertical distribution supported the conclusion that the atmospheric stability affects the vertical distribution of BrO.

  15. Ice flux divergence anomalies on 79north Glacier, Greenland

    DEFF Research Database (Denmark)

    Seroussi, H.; Morlighem, M.; Rignot, E.;

    2011-01-01

    The ice flux divergence of a glacier is an important quantity to examine because it determines the rate of temporal change of its thickness. Here, we combine high-resolution ice surface velocity observations of Nioghalvfjerdsfjorden (79north) Glacier, a major outlet glacier in north Greenland, with...... a dense grid of ice thickness data collected with an airborne radar sounder in 1998, to examine its ice flux divergence. We detect large variations, up to 100 m/yr, in flux divergence on grounded ice that are incompatible with what we know of the glacier surface mass balance, basal mass balance and...... onto a regular grid using a scheme (here block kriging) that does not conserve mass or ice flux. This problem is not unique to 79north Glacier but is common to all conventional ice thickness surveys of glaciers and ice sheets; and fundamentally limits the application of ice thickness grids to high...

  16. 79th Annual Meeting of the Psychometric Society

    CERN Document Server

    Bolt, Daniel; Wang, Wen-Chung; Douglas, Jeffrey; Chow, Sy-Miin

    2015-01-01

    These research articles from the 79th Annual Meeting of the Psychometric Society (IMPS) cover timely quantitative psychology topics, including new methods in item response theory, computerized adaptive testing, cognitive diagnostic modeling, and psychological scaling. Topics within general quantitative methodology include structural equation modeling, factor analysis, causal modeling, mediation, missing data methods, and longitudinal data analysis. These methods will appeal, in particular, to researchers in the social sciences. The 79th annual meeting took place in Madison, WI between July 21nd and 25th, 2014. Previous volumes to showcase work from the Psychometric Society’s Meeting are New Developments in Quantitative Psychology: Presentations from the 77th Annual Psychometric Society Meeting (Springer, 2013) and Quantitative Psychology Research: The 78th Annual Meeting of the Psychometric Society  (Springer, 2015).

  17. Identification of a group of brominated flame retardants as novel androgen receptor antagonists and potential neuronal and endocrine disrupters.

    Science.gov (United States)

    Kharlyngdoh, Joubert Banjop; Pradhan, Ajay; Asnake, Solomon; Walstad, Anders; Ivarsson, Per; Olsson, Per-Erik

    2015-01-01

    Brominated flame-retardants (BFRs) are used in industrial products to reduce the risk of fire. However, their continuous release into the environment is a concern as they are often persistent, bioaccumulating and toxic. Information on the impact these compounds have on human health and wildlife is limited and only a few of them have been identified to disrupt hormone receptor functions. In the present study we used in silico modeling to determine the interactions of selected BFRs with the human androgen receptor (AR). Three compounds were found to dock into the ligand-binding domain of the human AR and these were further tested using in vitro analysis. Allyl 2,4,6-tribromophenyl ether (ATE), 2-bromoallyl 2,4,6-tribromophenyl ether (BATE) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) were observed to act as AR antagonists. These BFRs have recently been detected in the environment, in house dust and in aquatic animals. The compounds have been detected at high concentrations in both blubber and brain of seals and we therefore also assessed their impact on the expression of L-type amino acid transporter system (LAT) genes, that are needed for amino acid uptake across the blood-brain barrier, as disruption of LAT gene function has been implicated in several brain disorders. The three BFRs down-regulated the expression of AR target genes that encode for prostate specific antigen (PSA), 5α-reductases and β-microseminoprotein. The potency of PSA inhibition was of the same magnitude as the common prostate cancer drugs, demonstrating that these compounds are strong AR antagonists. Western blot analysis of AR protein showed that ATE, BATE and DPTE decreased the 5α-dihydrotestosterone-induced AR protein levels, further confirming that these BFRs act as AR antagonists. The transcription of the LAT genes was altered by the three BFRs, indicating an effect on amino-acid uptake across cellular membranes and blood-brain barrier. This study demonstrated that ATE, BATE

  18. Raumanmeren peruskoulun 7.-9.-luokkalaisten ravitsemustottumukset ja kokemukset ravitsemuskasvatuksesta

    OpenAIRE

    Arvonen, Heidi

    2015-01-01

    Tämän opinnäytetyön tarkoituksena oli selvittää, millaiset ravitsemustottumukset Raumanmeren peruskoulun 7.-9.-luokkalaisilla on ja millaisia kokemuksia heillä on ravitsemuskasvatuksesta. Tavoitteena oli tuottaa luotettavaa tietoa oppilaiden ravitsemuksesta. Tutkimustiedolla voitaisiin tarvittaessa kehittää koulussa ja kouluterveydenhuollossa tapahtuvaa ravitsemuskasvatusta ja kohdentaa sitä eri osa-alueisiin. Opinnäytetyö toteutettiin kvantitatiivisella eli määrällisellä tutkimusmenetelm...

  19. Flotol-7,9 - a precipitant for ionic flotation

    International Nuclear Information System (INIS)

    The flotation properties of the industrial flotation agent flotol-7,9 are investigated using the extraction of Eu(III) from dilute HNO3 solutions as an example. Dependences are presented for the degree of Eu separation on the duration of keeping its complex precipitate with flotol and of the subsequent flotation and on the concentrations of flotation agent and HNO3. 3 refs., 4 tabs

  20. NT79: a Novel Neurotensin Analog with Selective Behavioral Effects

    OpenAIRE

    Boules, Mona; Liang, Yanqi; Briody, Siobhan; Miura, Tomofumi; Fauq, Irfan; Oliveros, Alfredo; Wilson, Mina; Khaniyev, Shaheen; Williams, Katrina; Li, Zhimin; Qi, Yanfei; Katovich, Michael; Richelson, Elliott

    2009-01-01

    Neurotensin, a tridecapeptide, is widely distributed in the brain and gastrointestinal tract. It possesses analgesic, hypothermic, and antipsychotic-like properties. Neurotensin’s effects are mediated mainly through two receptor subtypes, NTS1 and NTS2. Activation of NTS1 has been implicated in most of the pharmacological effects of neurotensin, but is associated with hypothermia and hypotension. We report on a novel neurotensin analog with higher selectivity to NTS2, namely, NT79 which exhib...

  1. Spectroscopy Division Progress report for 1977-79

    International Nuclear Information System (INIS)

    An account of the activities of the Spectroscopy Division of the Bhabha Atomic Research Centre, Bombay, covering the period 1977-79 is given. The activities broadly cover the areas of spectrochemical analysis, research and development programmes in the fields of atomic and molecular spectroscopy and design and fabrication of high precision optical instruments and electronic components required for the above programmes. (K.B.)

  2. 78 FR 55241 - Foreign-Trade Zone 79-Tampa, Florida, Foreign-Trade Subzone 79C-Cutrale Citrus Juices USA, Inc...

    Science.gov (United States)

    2013-09-10

    ... Register inviting public comment (78 FR 38922, 6/28/2013). The FTZ staff examiner reviewed the application... Foreign-Trade Zones Board Foreign-Trade Zone 79--Tampa, Florida, Foreign-Trade Subzone 79C--Cutrale Citrus... to the existing activation limit of FTZ 79, on behalf of Cutrale Citrus Juices USA, Inc....

  3. Kepler-79's low density planets

    International Nuclear Information System (INIS)

    Kepler-79 (KOI-152) has four planetary candidates ranging in size from 3.5 to 7 times the size of the Earth, in a compact configuration with orbital periods near a 1:2:4:6 chain of commensurability, from 13.5 to 81.1 days. All four planets exhibit transit timing variations with periods that are consistent with the distance of each planet to resonance with its neighbors. We perform a dynamical analysis of the system based on transit timing measurements over 1282 days of Kepler photometry. Stellar parameters are obtained using a combination of spectral classification and the stellar density constraints provided by light curve analysis and orbital eccentricity solutions from our dynamical study. Our models provide tight bounds on the masses of all four transiting bodies, demonstrating that they are planets and that they orbit the same star. All four of Kepler-79's transiting planets have low densities given their sizes, which is consistent with other studies of compact multiplanet transiting systems. The largest of the four, Kepler-79 d (KOI-152.01), has the lowest bulk density yet determined among sub-Saturn mass planets.

  4. Human Y-79 retinoblastoma cells exhibit specific insulin receptors

    Energy Technology Data Exchange (ETDEWEB)

    Saviolakis, G.A.; Kyritsis, A.P.; Chader, G.J.

    1986-07-01

    The presence of insulin receptors was investigated in human Y-79 retinoblastoma cells grown in suspension culture. The binding of (/sup 125/I) insulin to these cells was time, temperature, and pH dependent, was competed for by insulin and proinsulin but not other peptides, and was inhibited by antibodies against the insulin receptor. The Scatchard plot of insulin competition data was curvilinear and was resolved into a high-affinity (KD approximately 0.5 X 10(-9) M)/low-capacity (approximately 3000 sites/cell) and a low-affinity (KD approximately 1 X 10(-7) M)/high-capacity (approximately 155,000 sites/cell) component. Negative cooperativity was not found, in agreement with other studies in rodent neural cells. However, in contrast to studies with rodent cells, insulin specifically down-regulated its receptor on human Y-79 cells after prolonged exposure. In conclusion, these data show for the first time the presence of specific insulin receptors in human Y-79 retinoblastoma cells. Because these cells were previously shown to have several characteristics typical of neural cells, we propose their use as a model to study the effects of insulin on neural and retinal tissues of human origin.

  5. 40 CFR 79.60 - Good laboratory practices (GLP) standards for inhalation exposure health effects testing.

    Science.gov (United States)

    2010-07-01

    ... the CAA, it shall be a violation of this section and a violation of this rule (40 CFR part 79, subpart... under 40 CFR part 79 and may require the sponsor to develop data in accordance with the requirements of...) standards for inhalation exposure health effects testing. 79.60 Section 79.60 Protection of...

  6. Bromine monoxide/sulphur dioxide ratios in relation to volcanological observations at Mt. Etna 2006–2009

    OpenAIRE

    N. Bobrowski; Giuffrida, G

    2012-01-01

    Over a three year period, from 2006 to 2009, frequent scattered sun light DOAS measurements were conducted at Mt. Etna in a distance of around six kilometres downwind from the summit craters. During the same period and in addition to these measurements, volcanic observations were made by regularly visiting various parts of Mt. Etna.

    Results from these measurements and observations are presented and their relation is discussed. The focus of the investigation is the bromin...

  7. Utilization of a Green Brominating Agent for the Spectrophotometric Determination of Pipazethate HCl in Pure Form and Pharmaceutical Preparations

    Directory of Open Access Journals (Sweden)

    Ayman A. Gouda

    2013-01-01

    Full Text Available Five simple, accurate, and sensitive spectrophotometric methods (A–E have been described for the indirect assay of pipazethate HCl (PZT either in pure form or in pharmaceutical preparations. The proposed methods are based on the bromination of pipazethate HCl with a solution of excess bromate-bromide mixture in hydrochloric acid medium and subsequent estimation of the residual bromine by different reaction schemes. In the first three methods (A–C, the determination of the residual bromine is based on its ability to bleach the color of methyl orange, indigo carmine, or thymol blue dyes and measuring the absorbance at 520, 610, and 550 nm for methods A, B, and C, respectively. Methods D and E involves treating the unreacted bromine with a measured excess of iron(II, and the remaining iron(II is complexed with 1,10-phenanthroline, and the increase in absorbance is measured at 510 nm for method D and the resulting iron(III is complexed with thiocyanate and the absorbance is measured at 480 nm for method E. The different experimental parameters affecting the development and stability of the color are carefully studied and optimized. Regression analysis of the Beer-Lambert plots showed good correlation in the concentration ranges of 0.5–8.0 μg . The apparent molar absorptivity, Sandell's sensitivity, detection and quantitation limits were evaluated. The proposed methods have been applied and validated successfully for the analysis of the drug in its pure form and pharmaceutical formulations with mean recoveries of 99.94%–100.15% and relative standard deviation ≤1.53. No interference was observed from a common pharmaceutical adjuvant. Statistical comparison of the results with the reference method shows excellent agreement and indicates no significant difference in accuracy and precision.

  8. Comparison of Nuclear Activation Methods for Bromine. Instrumental Analyses of Pesticides in Plant Materials Close to the Limit of Sensitivity

    International Nuclear Information System (INIS)

    There has been worldwide interest in pesticide residue analysis for control and ecological purposes. Although several agricultural research establishments have in the past developed suitable radioisotope tracer techniques to detect and remove organic pesticides from food, suitable micro-analytical techniques for the measurement of traces of toxic elements present in these materials have not been available. In cooperation with the United States Department of Agriculture, Plant Pest Control Laboratory, an investigation has been conducted on the use of neutron activation techniques for determining bromine, arsenic and mercury residues in soils, foliage, fruit, and vegetable materials. This paper discusses the various instrumental and data reduction techniques which were developed to measure traces of bromine by neutron activation methods, especially those employed in the limit of sensitivity range wherein special statistical methods are necessary. A large number of samples of soils, foliage, orange and vegetable materials, activated in the Texas A and M Research Reactor were counted at appropriate times after activation using three different counting systems: firstly, an automated system with an Nal (Tl) spectrometer; secondly, a 2 cm3 Ge(Li) solid-state detector connected to a Victoreen 3200-channel analyzer; and thirdly a slow γ-γ coincidence unit. The spectral data from the automated system were reduced by the AA-6 least squares method, and alternatively by means of computer spectrum stripping and peak area computation methods. The photopeak activities from the solid-state detector spectra were measured by the peak area method. The results obtained from the three counting systems using different data reduction techniques were compared to determine the best for the measurement of bromine concentration in the limit-of-sensitivity range. The γ-γ coincidence counting technique appears to have advantages in measuring the bromine content even in the ppm range in

  9. Bromine is an essential trace element for assembly of collagen IV scaffolds in tissue development and architecture

    OpenAIRE

    McCall, A. Scott; Cummings, Christopher F.; Bhave, Gautam; Vanacore, Roberto; Page-McCaw, Andrea; Hudson, Billy G.

    2014-01-01

    Bromine is ubiquitously present in animals as ionic bromide (Br−) yet has no known essential function. Herein, we demonstrate that Br− is a required cofactor for peroxidasin-catalyzed formation of sulfilimine crosslinks, a post-translational modification essential for tissue development and architecture found within the collagen IV scaffold of basement membranes (BMs). Bromide, converted to hypobromous acid, forms a bromosulfonium-ion intermediate that energetically selects for sulfilimine fo...

  10. Prenatal Exposure to Organohalogens, Including Brominated Flame Retardants, Influences Motor, Cognitive, and Behavioral Performance at School Age

    OpenAIRE

    Roze, Elise; Meijer, Lisethe; Bakker, Attie; Van Braeckel, Koenraad N. J. A.; Sauer, Pieter J. J.; Bos, Arend F

    2009-01-01

    Background Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain. Objective We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age. Methods This study was part of the prospective Groningen infant COMPARE (Comparison of Exposure-Effect Pathways to Improve the Assessment of Human Health Risks of Complex Environmental Mixtures of Organoha...

  11. An investigation into the sensitivity of the atmospheric chlorine and bromine loading using a globally averaged mass balance model

    Science.gov (United States)

    Dowdell, David C.; Matthews, G. Peter; Wells, Ian

    Two globally averaged mass balance models have been developed to investigate the sensitivity and future level of atmospheric chlorine and bromine as a result of the emission of 14 chloro- and 3 bromo-carbons. The models use production, growth, lifetime and concentration data for each of the halocarbons and divide the production into one of eight uses, these being aerosol propellants, cleaning agents, blowing agents in open and closed cell foams, non-hermetic and hermetic refrigeration, fire retardants and a residual "other" category. Each use category has an associated emission profile which is built into the models to take into account the proportion of halocarbon retained in equipment for a characteristic period of time before its release. Under the Montreal Protocol 3 requirements, a peak chlorine loading of 3.8 ppb is attained in 1994, which does not reduce to 2.0 ppb (the approximate level of atmospheric chlorine when the ozone hole formed) until 2053. The peak bromine loading is 22 ppt, also in 1994, which decays to 12 ppt by the end of next century. The models have been used to (i) compare the effectiveness of Montreal Protocols 1, 2 and 3 in removing chlorine from the atmosphere, (ii) assess the influence of the delayed emission assumptions used in these models compared to immediate emission assumptions used in previous models, (iii) assess the relative effect on the chlorine loading of a tightening of the Montreal Protocol 3 restrictions, and (iv) calculate the influence of chlorine and bromine chemistry as well as the faster phase out of man-made methyl bromide on the bromine loading.

  12. Crosstalk between SET7/9-dependent methylation and ARTD1-mediated ADP-ribosylation of histone H1.4

    Directory of Open Access Journals (Sweden)

    Kassner Ingrid

    2013-01-01

    Full Text Available Abstract Background Different histone post-translational modifications (PTMs fine-tune and integrate different cellular signaling pathways at the chromatin level. ADP-ribose modification of histones by cellular ADP-ribosyltransferases such as ARTD1 (PARP1 is one of the many elements of the histone code. All 5 histone proteins were described to be ADP-ribosylated in vitro and in vivo. However, the crosstalk between ADP-ribosylation and other modifications is little understood. Results In experiments with isolated histones, it was found that ADP-ribosylation of H3 by ARTD1 prevents H3 methylation by SET7/9. However, poly(ADP-ribosylation (PARylation of histone H3 surprisingly allowed subsequent methylation of H1 by SET7/9. Histone H1 was thus identified as a new target for SET7/9. The SET7/9 methylation sites in H1.4 were pinpointed to the last lysine residues of the six KAK motifs in the C-terminal domain (K121, K129, K159, K171, K177 and K192. Interestingly, H1 and the known SET7/9 target protein H3 competed with each other for SET7/9-dependent methylation. Conclusions The results presented here identify H1.4 as a novel SET7/9 target protein, and document an intricate crosstalk between H3 and H1 methylation and PARylation, thus implying substrate competition as a regulatory mechanism. Thereby, these results underline the role of ADP-ribosylation as an element of the histone code.

  13. Inorganic bromine and iodine in the TTL and in the mid-latitude lower stratosphere

    Science.gov (United States)

    Volkamer, Rainer; Apel, Eric; Atlas, Elliot; Bowdalo, Dene; Bresch, Jim; Dix, Barbara; Eloranta, Ed; Evans, Matthew; Gao, Ru-Shan; Jacob, Daniel; Kinnison, Doug; Koenig, Theodore; Lamarque, Jean-Francois; Morley, Bruce; Pierce, Brad; Saiz-Lopez, Alfonso; Salawitch, Ross; Schmidt, Johan; Wang, Siyuan

    2015-04-01

    Tropospheric chemistry of halogens (bromine and iodine) over tropical oceans modifies ozone and atmospheric aerosols, yet atmospheric models remain largely untested for lack of vertically resolved measurements of bromine monoxide (BrO) and iodine monoxide (IO) in the tropical troposphere. We present recent field measurements of BrO, IO, and their organic precursors that were conducted within the framework of the Tropical Ocean tRoposphere Exchange of Reactive halogen species and Oxygenated volatile organic compounds (TORERO, Jan/Feb 2012) over the tropical Eastern Pacific Ocean (tEPO). TORERO deployed an innovative payload of optical spectroscopic-, mass spectrometric-, and remote sensing instruments aboard the NSF/NCAR GV aircraft (HIAPER) with the objective to probe the composition of the TTL. BrO and IO were measured by the University of Colorado Airborne Multi AXis Differential Optical Absorption Spectroscopy (CU AMAX-DOAS) instrument, organic precursor gases by the Trace Organic Gas Analyzer (TOGA), and in situ aerosol size distributions by an Ultra High Sensitivity Aerosol Spectrometer (UHSAS); other parameters were also measured on the aircraft and used to constrain a photochemical box model to infer BrY. The measured BrO concentration strongly increased with altitude to 3.0 pptv BrO at 14.5 km (RF12, 9.1 to 8.6°N; 101.2 to 97.4°W). The average tropospheric BrO VCD in the tropics was 1.5 x1013 molec cm-2, which is in reasonable agreement with earlier satellite observations in the study area (~1.6 x1013 molec cm-2, Theys et al., 2011). However, the observed BrO VCD is 2-4 times higher than predictions from the GEOS-Chem model. Early results from the recent CONTRAST field campaign (CONvective TRansport of Active Species in the Tropics, Jan/Feb 2014) suggest lower tropospheric BrO over the Western Pacific Ocean (compared to the tEPO), but BrO is still higher than predicted by the CAM-Chem model. The largest model-measurement differences are observed in the

  14. Brominated flame retardants in the surrounding soil of two manufacturing plants in China: Occurrence, composition profiles and spatial distribution.

    Science.gov (United States)

    Li, Wen-Long; Liu, Li-Yan; Zhang, Zi-Feng; Song, Wei-Wei; Huo, Chun-Yan; Qiao, Li-Na; Ma, Wan-Li; Li, Yi-Fan

    2016-06-01

    Surface soil samples were collected surrounding two brominated flame retardants (BFRs) manufacturing plants in China in August 2014 and analyzed for 23 polybrominated diphenyl ethers (PBDEs) and 8 novel brominated flame retardants (NBFRs). BDE209 and decabromodiphenylethane (DBDPE) were the predominant compounds in soil with the median levels of 1600 and 560 ng/g dw, respectively. The PBDEs profiles in soil samples were consistent with that of commercial product (comDecaBDE). The percentage contributions to total PBDEs decreased from higher to lower brominated homologues. Lower concentrations of NBFRs (excluding DBDPE) were detected in soil surrounding the two plants, suggesting they are byproducts or degradation products of the manufacturing activities. The concentrations of most BFRs dropped exponentially within 3-5 km of the manufacturing plants, suggesting recent deposition of these compounds to the soil. Directional distribution indicated that PBDEs and DBDPE concentrations were highest in the north direction of Plants 1. Three-day air parcel forward trajectories confirmed that the air parcel was responsible for the higher concentration of BFRs in the soil of north direction of the plant. PMID:26874313

  15. Occurrence of brominated flame retardants in black thermo cups and selected kitchen utensils purchased on the European market.

    Science.gov (United States)

    Samsonek, J; Puype, F

    2013-01-01

    In order to screen for the presence of a recycled polymer waste stream from waste electric and electronic equipment (WEEE), a market survey was conducted on black plastic food-contact articles (FCA). An analytical method was applied combining X-ray fluorescence spectrometry (XRF) with thermal desorption gas chromatography coupled with mass spectrometry (thermal desorption GC-MS). Firstly, XRF spectrometry was applied to distinguish bromine-positive samples. Secondly, bromine-positive samples were submitted for identification by thermal desorption GC-MS. Generally, the bromine-positive samples contained mainly technical decabromodiphenyl ether (decaBDE). Newer types of BFRs such as tetrabromobisphenol A (TBBPA), tetrabromobisphenol A bis(2,3-dibromopropyl), ether (TBBPA-BDBPE) and decabromodiphenylethane (DBDPE), replacing the polybrominated diphenyleters (PBDEs) and polybrominated diphenyls (PBBs), were also identified. In none of the tested samples were PBBs or hexabromocyclododecane (HBCD) found. Polymer identification was carried out using Fourier-transformed infrared spectroscopy measurement (FTIR) on all samples. The results indicate that polypropylene-polyethylene copolymers (PP-PE) and mainly styrene-based food-contact materials, such as acrylonitrile-butadiene-styrene (ABS) have the highest risk of containing BFRs. PMID:24040839

  16. Bromination of Graphene: A New Route to Making High Performance Transparent Conducting Electrodes with Low Optical Losses

    KAUST Repository

    Mansour, Ahmed E.

    2015-07-22

    The unique optical and electrical properties of graphene have triggered great interest in its application as a transparent conducting electrode material and significant effort has been invested in achieving high conductivity while maintaining transparency. Doping of graphene has been a popular route for reducing its sheet resistance, but this has typically come at a significant cost in optical transmission. We demonstrate doping of few layers graphene with bromine as a means of enhancing the conductivity via intercalation without major optical losses. Our results demonstrate the encapsulation of bromine leads to air-stable transparent conducting electrodes with five-fold improvement of sheet resistance reaching at the cost of only 2-3% loss of optical transmission. The remarkably low tradeoff in optical transparency leads to the highest enhancements in the figure of merit reported thus far for FLG. Furthermore, we tune the workfunction by up to 0.3 eV by tuning the bromine content. These results should help pave the way for further development of graphene as a potential substitute to transparent conducting polymers and metal oxides used in optoelectronics, photovoltaics and beyond.

  17. Occurrence of PBDEs and other alternative brominated flame retardants in sludge from wastewater treatment plants in Korea.

    Science.gov (United States)

    Lee, Sunggyu; Song, Geum-Ju; Kannan, Kurunthachalam; Moon, Hyo-Bang

    2014-02-01

    Studies on the occurrence of polybrominated diphenyl ethers (PBDEs) and other alternative brominated flame retardants in the environment are scarce. In this study, PBDEs and non-PBDE brominated flame retardants (NBFRs), including decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), were measured in sludge collected from three types of wastewater treatment plants (WWTPs) in Korea. Total concentrations of PBDEs (∑PBDE) in sludge ranged from 298 to 48,000 (mean: 3240) ng/g dry weight. Among 10 NBFRs analyzed, DBDPE and BTBPE were the only ones detected in sludge samples. Concentrations of DBDPE and BTBPE ranged from parametric multidimensional scaling ordination showed that congener profiles of PBDEs in sludge are dependent on the types of WWTPs. Almost all sludge samples contained a low ratio (mean: 0.18) of DBDPE/BDE 209, indicating an on-going contamination by PBDEs in Korea. However, the high ratios (>1) of DBDPE/BDE 209 were found in sludge from I-WWTPs, reflecting a shift in the usage pattern of BFRs by the Korean industry. The nationwide annual emission fluxes of ∑PBDE, DBDPE and BTBPE via WWTPs to the environment were estimated to be 7400, 480, and 3.7 kg/year, respectively. This is the first study on the occurrence of alternative brominated flame retardants in sludge from Korea. PMID:23993837

  18. Potential formation of PCDD/Fs and related bromine-substituted compounds from heating processes for ashes

    International Nuclear Information System (INIS)

    Thermal experiments were conducted using real boiler ash and fly ash samples from three types of municipal or industrial solid waste incineration plants to understand the formation reactions of polychlorinated dibenzo-p-dioxin and furans (PCDD/Fs) and related bromine compounds that were chlorinated-brominated dibenzodioxins and furans (PXDD/Fs) and polybrominated dibenzo-p-dioxin and furans (PBDD/Fs). The results obtained were as follows: The formation of PCDD/Fs was clearly shown, and fly ash containing abundant carbon matter had a significant potential for de novo synthesis. The homologous distribution change apparently showed that the formation of PXDD/Fs occurred from the substitution of a bromine atom with a chlorine atom in the PCDD/F molecules. This suggests that PXDD/Fs are usually formed with PCDD/Fs on the ash. PBDD/Fs might be formed from any reaction mechanism different from that of PXDD/Fs. The existence of carbonaceous matters always does not mean the potential formation of PCDD/Fs. However, any addition of catalytic copper may influence the nature of ash to increase the formation potential. The findings suggest that there are many instances that result in the unintended production of trace hazardous pollutants in the incineration process and show that careful and sophisticated control is required to prevent the formation of pollutants.

  19. Lumbar myelography in 79 dogs, using different puncture sites

    International Nuclear Information System (INIS)

    Lumbar myelography was performed in 79 dogs either before spinal surgery or as part of an investigation of neurological disease. In small dogs the site of the puncture was between L1 and L5, avoiding the lumbosacral intumescence, whereas in large dogs the site was between T13 and L2. It was found that a lumbar puncture cranial to the lumbar intumescence was easier and caused no problems. The lumbar puncture was unsuccessful in three obese dogs. In 72 per cent of the cases the myelogram revealed a lesion, and the main cause of a non-diagnostic myelogram was epidural leakage

  20. The Iranian Revolution, 1977–79: Interaction and Transformation

    DEFF Research Database (Denmark)

    Seeberg, Peter

    2014-01-01

    enhanced the attention it received, and still receives from academic research. Taking its point of departure in theories of revolution by Theda Skocpol, this article discusses the character of the revolution. The article problematises Skocpol’s theories through a discussion of the special characteristics......ABSTRACT Within a short time after the Iranian revolution of 1977-79, a number of studies were published concerning the dramatic process. It was presumably the spectacular turn of events, comprehensive media coverage, and relatively long period of time over which the revolution took place that...

  1. Theoretical study of the reaction kinetics of atomic bromine with tetrahydropyran

    KAUST Repository

    Giri, Binod

    2015-02-12

    A detailed theoretical analysis of the reaction of atomic bromine with tetrahydropyran (THP, C5H10O) was performed using several ab initio methods and statistical rate theory calculations. Initial geometries of all species involved in the potential energy surface of the title reaction were obtained at the B3LYP/cc-pVTZ level of theory. These molecular geometries were reoptimized using three different meta-generalized gradient approximation (meta-GGA) functionals. Single-point energies of the stationary points were obtained by employing the coupled-cluster with single and double excitations (CCSD) and fourth-order Møller-Plesset (MP4 SDQ) levels of theory. The computed CCSD and MP4(SDQ) energies for optimized structures at various DFT functionals were found to be consistent within 2 kJ mol-1. For a more accurate energetic description, single-point calculations at the CCSD(T)/CBS level of theory were performed for the minimum structures and transition states optimized at the B3LYP/cc-pVTZ level of theory. Similar to other ether + Br reactions, it was found that the tetrahydropyran + Br reaction proceeds in an overall endothermic addition-elimination mechanism via a number of intermediates. However, the reactivity of various ethers with atomic bromine was found to vary substantially. In contrast with the 1,4-dioxane + Br reaction, the chair form of the addition complex (c-C5H10O-Br) for THP + Br does not need to undergo ring inversion to form a boat conformer (b-C4H8O2-Br) before the intramolecular H-shift can occur to eventually release HBr. Instead, a direct, yet more favorable route was mapped out on the potential energy surface of the THP + Br reaction. The rate coefficients for all relevant steps involved in the reaction mechanism were computed using the energetics of coupled cluster calculations. On the basis of the results of the CCSD(T)/CBS//B3LYP/cc-pVTZ level of theory, the calculated overall rate coefficients can be expressed as kov.,calc.(T) = 4.60 × 10

  2. Development of Zinc/Bromine Batteries for Load-Leveling Applications: Phase 1 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Eidler, Phillip

    1999-07-01

    The Zinc/Bromine Load-Leveling Battery Development contract (No. 40-8965) was partitioned at the outset into two phases of equal length. Phase 1 started in September 1990 and continued through December 1991. In Phase 1, zinc/bromine battery technology was to be advanced to the point that it would be clear that the technology was viable and would be an appropriate choice for electric utilities wishing to establish stationary energy-storage facilities. Criteria were established that addressed most of the concerns that had been observed in the previous development efforts. The performances of 8-cell and 100-cell laboratory batteries demonstrated that the criteria were met or exceeded. In Phase 2, 100-kWh batteries will be built and demonstrated, and a conceptual design for a load-leveling plant will be presented. At the same time, work will continue to identify improved assembly techniques and operating conditions. This report details the results of the efforts carried out in Phase 1. The highlights are: (1) Four 1-kWh stacks achieved over 100 cycles, One l-kWh stack achieved over 200 cycles, One 1-kWh stack achieved over 300 cycles; (2) Less than 10% degradation in performance occurred in the four stacks that achieved over 100 cycles; (3) The battery used for the zinc loading investigation exhibited virtually no loss in performance for loadings up to 130 mAh/cm{sup 2}; (4) Charge-current densities of 50 ma/cm{sup 2} have been achieved in minicells; (5) Fourteen consecutive no-strip cycles have been conducted on the stack with 300+ cycles; (6) A mass and energy balance spreadsheet that describes battery operation was completed; (7) Materials research has continued to provide improvements in the electrode, activation layer, and separator; and (8) A battery made of two 50-cell stacks (15 kWh) was produced and delivered to Sandia National Laboratories (SNL) for testing. The most critical development was the ability to assemble a battery stack that remained leak free. The

  3. Modelling the impact of chlorine and bromine emissions from large Plinian eruptions on ozone

    Science.gov (United States)

    Brenna, Hans; Krüger, Kirstin; Kutterolf, Steffen

    2016-04-01

    Large Plinian volcanic eruptions inject large amounts of atmosphere-relevant gases (e.g. S, Cl, Br) and materials into the stratosphere. If the eruption occurs in the tropics, it can have a global impact due to the dispersal through the large scale meridional overturning circulation. Most climate model studies concentrate on the sulfate aerosol effects on climate. In contrast, ozone-depletion initiated by volcanic halogens from tropical eruptions was believed to play an insignificant role for the global atmosphere, based on observations from the recent El Chichon and Pinatubo eruptions. New results regarding the halogen release by Plinian eruptions, as well as recent volcanic plume observations and model simulations facilitate now our investigation into what effect the combined chlorine and bromine emissions from large tropical eruptions have on ozone and the atmosphere in general. A complete halogen data set for the last 200 ka (Kutterolf et al., 2015), derived by the petrological method from paleo-eruptions of the Central American Volcanic Arc (CAVA), are used to force simulations with the advanced chemistry climate model WACCM (Whole Atmosphere Community Climate Model). The goal is to quantify the impact of volcanic halogens on the preindustrial atmosphere when the background chlorine levels were low compared to the present day with the main focus on stratospheric ozone. We carried out 5 model simulations assuming that 10% of the Cl and Br (9.51e+6 kg Br and 2.93e+9 kg Cl) emitted from the average CAVA eruption is injected into the tropical stratosphere during January. The model response reveals a global impact on the ozone layer affecting via radiation also atmospheric dynamics for more than 5 years. Given the current decline in anthropogenic chlorine, the results will become relevant for future halogen-rich explosive eruptions in the tropics. References: Kutterolf, S., T. Hansteen, A. Freundt, H. Wehrmann, K. Appel, K. Krüger, and W. Pérez (2015), Bromine

  4. Temperature dependence of bromine activation due to reaction with ozone in a proxy for organic aerosols

    Science.gov (United States)

    Edebeli, Jacinta; Ammann, Markus; Gilgen, Anina; Eichler, Anja; Schneebeli, Martin; Bartels-Rausch, Thorsten

    2016-04-01

    The discovery of boundary layer ozone depletion events in the Polar Regions [1] and in the mid-latitudes [2], two areas of very different temperature regimes, begs the question of temperature dependence of reactions responsible for these observations [3]. These ODEs have been attributed to ozone reacting with halides leading to reactive halogens (halogen activation) of which bromide is extensively studied, R1 - R3 [4, 5] (R1 is a multiphase reaction). O3 + Br‑→ O2 + OBr‑ (R1) OBr‑ + H+ ↔ HOBr (R2) HOBr + H+ + Br‑→ Br2 + H2O (R3) Despite extensive studies of ozone-bromide interactions, the temperature dependence of bromine activation is not clear [3]. This limits parameterization of the involved reactions and factors in atmospheric models [3, 6]. Viscosity changes in the matrix (such as organic aerosols) due to temperature have been shown to influence heterogeneous reaction rates and products beyond pure temperature effect [7]. With the application of coated wall flow-tubes, the aim of this study is therefore to investigate the temperature dependence of bromine activation by ozone interaction while attempting to characterize the contributions of the bulk and surface reactions to observed ozone uptake. Citric acid is used in this study as a hygroscopically characterized matrix whose viscosity changes with temperature and humidity. Here, we present reactive ozone uptake measured between 258 and 289 K. The data show high reproducibility. Comparison of measured uptake with modelled bulk uptake at different matrix compositions (and viscosities) indicate that bulk reactive uptake dominates, but there are other factors which still need further consideration in the model. References 1. Barrie, L.A., et al., Nature, 1988. 334: p. 138 - 141. 2. Hebestreit, K., et al., Science, 1999. 283: p. 55-57. 3. Simpson, W.R., et al., Atmospheric Chemistry and Physics, 2007. 7: p. 4375 - 4418. 4. Haag, R.W. and J. Hoigné, Environ Sci Technol, 1983. 17: p. 261-267. 5. Oum

  5. Investigation of the Stratospheric Bromine Chemistry by Balloon-Borne Spectroscopic Observations and Photochemical Modelling: A Case Study of J(BrONO2) / k[BrO][NO2

    OpenAIRE

    Kreycy, Sebastian

    2013-01-01

    Besides chlorine, bromine is the second most important halogen when it comes to the destruction of ozone in the stratosphere. Although 150 times more chlorine than bromine is transported into the stratosphere, the higher ozone-depleting efficiency of bromine (by a factor of 45) makes it very important for catalytic cycles. In this study, balloon-borne DOAS (Differential Optical Absorption Spectroscopy) measurements of direct sunlight and limb measurements of scattered skylight, recorded...

  6. Analysis of reactive bromine production and ozone depletion in the Arctic boundary layer using 3-D simulations with GEM-AQ: inference from synoptic-scale patterns

    Directory of Open Access Journals (Sweden)

    K. Toyota

    2011-04-01

    Full Text Available Episodes of high bromine levels and surface ozone depletion in the springtime Arctic are simulated by an online air-quality model, GEM-AQ, with gas-phase and heterogeneous reactions of inorganic bromine species and a simple scheme of air-snowpack chemical interactions implemented for this study. Snowpack on sea ice is assumed to be the only source of bromine to the atmosphere and to be capable of converting relatively stable bromine species to photolabile Br2 via air-snowpack interactions. A set of sensitivity model runs are performed for April 2001 at a horizontal resolution of approximately 100 km×100 km in the Arctic, to provide insights into the effects of temperature and the age (first-year, FY, versus multi-year, MY of sea ice on the release of reactive bromine to the atmosphere. The model simulations capture much of the temporal variations in surface ozone mixing ratios as observed at stations in the high Arctic and the synoptic-scale evolution of areas with enhanced BrO column amount ("BrO clouds" as estimated from satellite observations. The simulated "BrO clouds" are in modestly better agreement with the satellite measurements when the FY sea ice is assumed to be more efficient at releasing reactive bromine to the atmosphere than on the MY sea ice. Surface ozone data from coastal stations used in this study are not sufficient to evaluate unambiguously the difference between the FY sea ice and the MY sea ice as a source of bromine. The results strongly suggest that reactive bromine is released ubiquitously from the snow on the sea ice during the Arctic spring while the timing and location of the bromine release are largely controlled by meteorological factors. It appears that a rapid advection and an enhanced turbulent diffusion associated with strong boundary-layer winds drive transport and dispersion of ozone to the near-surface air over the sea ice, increasing the oxidation rate of bromide (Br in the surface

  7. Bromine monoxide/sulphur dioxide ratios in relation to volcanological observations at Mt. Etna 2006–2009

    Directory of Open Access Journals (Sweden)

    N. Bobrowski

    2012-03-01

    Full Text Available Over a three year period, from 2006 to 2009, frequent scattered sun light DOAS measurements were conducted at Mt. Etna in a distance of around six kilometres downwind from the summit craters. During the same period and in addition to these measurements, volcanic observations were made by regularly visiting various parts of Mt. Etna.

    Results from these measurements and observations are presented and their relation is discussed. The focus of the investigation is the bromine monoxide/sulphur dioxide (BrO/SO2 ratio, and its variability in relation to volcanic processes.

    That the halogen/sulphur ratio can serve as a precursor or indicator for the onset of eruptive activity was already proposed by earlier works (e.g. Noguchi and Kamiya, 1963; Menyailov, 1975; Pennisi and Cloarec, 1998; Aiuppa, 2002. However, there is still a limited understanding today because of the complexity with which halogens are released, depending on magma composition and degassing conditions. Our understanding of these processes is far from complete, for example of the rate and mechanism of bubble nucleation, growth and ascent in silicate melts (Carroll and Holloway, 1994, the halogen vapour-melt partitioning and the volatile diffusivity in the melt (Aiuppa et al., 2009.

    With this study we aim to add one more piece to the puzzle of what halogen/sulphur ratios might tell about volcanic activities. Our data set shows an increase of the BrO/SO2 ratio several weeks prior to an eruption, followed by a decline before and during the initial phase of eruptive activities. Towards the end of activity or short afterwards, the ratio increases to baseline values again and remains more or less constant during quiet phases. To explain the observed evolution of the BrO/SO2 ratio, a first empirical model is proposed. This model suggests that bromine, unlike chlorine and fluorine, is less soluble in the magmatic melt than sulphur

  8. Brominated flame retardants in the indoor environment - Comparative study of indoor contamination from three countries.

    Science.gov (United States)

    Venier, Marta; Audy, Ondřej; Vojta, Šimon; Bečanová, Jitka; Romanak, Kevin; Melymuk, Lisa; Krátká, Martina; Kukučka, Petr; Okeme, Joseph; Saini, Amandeep; Diamond, Miriam L; Klánová, Jana

    2016-09-01

    Concentrations of more than 20 brominated flame retardants (FRs), including polybrominated diphenyl ethers (PBDEs) and emerging FRs, were measured in air, dust and window wipes from 63 homes in Canada, the Czech Republic and the United States in the spring and summer of 2013. Among the PBDEs, the highest concentrations were generally BDE-209 in all three matrices, followed by Penta-BDEs. Among alternative FRs, EHTBB and BEHTBP were detected at the highest concentrations. DBDPE was also a major alternative FR detected in dust and air. Bromobenzenes were detected at lower levels than PBDEs and other alternative FRs; among the bromobenzenes, HBB and PBEB were the most abundant compounds. In general, FR levels were highest in the US and lowest in the Czech Republic - a geographic trend that reflects the flame retardants' market. No statistically significant differences were detected between bedroom and living room FR concentrations in the same house (n=10), suggesting that sources of FRs are widespread indoors and mixing between rooms. The concentrations of FRs in air, dust, and window film were significantly correlated, especially for PBDEs. We found a significant relationship between the concentrations in dust and window film and in the gas phase for FRs with log KOA values values >14. This hypothesis was confirmed by a large discrepancy between values predicted using a partitioning model and the measured values for FRs with log KOA values >14. PMID:27248661

  9. Simple and rapid quantification of brominated vegetable oil in commercial soft drinks by LC-MS.

    Science.gov (United States)

    Chitranshi, Priyanka; Gamboa da Costa, Gonçalo

    2016-12-15

    We report here a simple and rapid method for the quantification of brominated vegetable oil (BVO) in soft drinks based upon liquid chromatography-electrospray ionization mass spectrometry. Unlike previously reported methods, this novel method does not require hydrolysis, extraction or derivatization steps, but rather a simple "dilute and shoot" sample preparation. The quantification is conducted by mass spectrometry in selected ion recording mode and a single point standard addition procedure. The method was validated in the range of 5-25μg/mL BVO, encompassing the legal limit of 15μg/mL established by the US FDA for fruit-flavored beverages in the US market. The method was characterized by excellent intra- and inter-assay accuracy (97.3-103.4%) and very low imprecision [0.5-3.6% (RSD)]. The direct nature of the quantification, simplicity, and excellent statistical performance of this methodology constitute clear advantages in relation to previously published methods for the analysis of BVO in soft drinks. PMID:27451219

  10. Formation of brominated trihalomethanes in chlorinated drinking-water from Lake Constance

    International Nuclear Information System (INIS)

    The formation of trihalomethanes (THMs) in raw water and drinking water from Lake Constance containing low amounts of DOC and bromide was studied with special emphasis on brominated trihalomethanes (Br-THMs). If the raw water was ozonated prior to chlorination, the formation of THMs was reduced by 37%, and if a rapid sandfiltration was interposed, the THM-formation was again slightly enhanced. The percentage of Br-THMs on total-THMs increased from 16% to 35% during the treatment process. In the drinking water distribution system of BWV the formation of Br-THMs and CHCl3 was studied with respect to residence time and post-chlorination. Unless the post-chlorination was performed, the THM-formation in the distribution system resembled that obtained from laboratory studies, except for small amounts of THMs being purged due to transport in the mains and residence in the reservoirs. Post-chlorination increased CHCl3- and the CHBrCl2-formation, but there was no effect on the formation of CHBr2Cl and CHBr3. However, the total THM-concentration in the drinking water never exceeded the German drinking water standard of 10 μg/L. (orig.)

  11. In vitro screening of the endocrine disrupting potency of brominated flame retardants and their metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Hamers, T.; Kamstra, J.H. [Inst. for Environmental Studies (IVM), Amsterdam (Netherlands); Sonneveld, E. [BioDetection Systems (BDS), Amsterdam (Netherlands); Murk, A.J. [Wageningen Univ., Toxicology Group, Wageningen (Netherlands); Zegers, B.N.; Boon, J.P. [Royal Netherlands Inst. for Sea Research (NIOZ), Den Burg (Netherlands); Brouwer, A. [Umea Univ., Umea (Sweden)

    2004-09-15

    Substantial evidence is recently becoming available that brominated flame retardants (BFRs) are potential endocrine disruptors. The toxicological profile of BFRs, however, is too incomplete and insufficient to perform human and ecological risk assessment. To fill these gaps, the EU funded research program FIRE was started in December 2002. This program aims at the identification and toxicological characterization of the most potent and environmentally relevant BFRs and their possible risk for human and wildlife health. As part of a hazard identification approach, twenty seven BFRs have been selected within the framework of FIRE for pre-screening their endocrinedisrupting potencies. Selection of test compounds was based on a maximal variation in physicochemical characteristics of BFRs within the test set, allowing the establishment of quantitative structure-activity relationships (QSARs). In addition, environmental relevance (e.g. high production volumes and persistence) and availability for testing were used as selection criteria. BFRs were tested in seven different in vitro bioassays for their potency to interfere via estrogenic, thyroidal, androgenic, progestagenic, and Ah-receptor mediated pathways. Metabolisation rates of BFRs were determined using phenobarbital-induced rat liver microsomes. Finally, the endocrine disrupting potency of the metabolites was determined in the same in vitro bio-assays and compared to the potency of the parent compounds.

  12. Characterizing Variability in the Spatial Distribution of Bromine Explosion Events in the Vicinity of Barrow, Alaska

    Science.gov (United States)

    Peterson, P.; Pratt, K.; Simpson, W. R.; Shepson, P. B.; Pöhler, D.; Friess, U.; Zielcke, J.; Platt, U.; Nghiem, S. V.; Sihler, H.

    2015-12-01

    Reactive halogens (e.g. Br, BrO) are produced photochemically during springtime in the Arctic. Some dramatic effects of these halogen species are known (e.g. ozone depletion, mercury deposition), but changes in atmospheric composition related to this halogen chemistry, particularly those related to increasing sea ice loss and the transformation of Arctic sea ice cover, are unknown. In March 2012, the Bromine, Ozone, Mercury EXperiment (BROMEX) provided an opportunity to enhance our understanding of the spatial and temporal variability of halogen chemistry in the vicinity of Barrow, Alaska. During BROMEX, we used Multiple Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) to measure BrO lower tropospheric vertical column densities (LT-VCD) and near-surface mixing ratios at Barrow, as well as on land-fast ice 40 km north east of Barrow, and a drifting platform on seasonal sea ice west of Barrow. Concurrently, an aircraft equipped with the Heidelberg Airborne Imaging DOAS Instrument (HAIDI) collected airborne BrO data at altitudes up to 3 km. These measurements showed several instances of spatial gradients in BrO between measurement sites, as well as times when BrO was present up to 1km aloft. We explore explanations for these features using local and synoptic meteorology, back-trajectory modelling, MODIS and airborne imagery, as well as satellite-instrument-based maps of synoptic sea ice classes and tropospheric BrO.

  13. [Optimization of determination of aflatoxins in foods with bromine postcolumn derivatization].

    Science.gov (United States)

    Czerwiecki, Ludwik; Wilczyńska, Grazyna

    2007-01-01

    The method for determination of aflatoxin B1, B2, G1 i G2 in nuts, culinary spices, cereals and cereal products was described. To optimize the analytical procedure in several products, condition of proper extraction, clean-up, HPLC and detection were selected. After extraction by means of methanol and water (80+20 v/v) or (70+30 v/v), clean-up on IAC columns, HPLC on C18 columns--Nucleosil and Nova Pak with mobile phase-methanol, acetonitrile, water (20+20+60 v/v) was performed. For fluorometric detection at 362/430 nm, post-column derivatization of aflatoxin B1 and G1 with bromine was carried out. The mean recovery of the method depending on matrix and aflatoxin, was 52-102% at RSD% 0.2-8.3. LOD and LOQ, respectively were: 0.01 and 0.02 microg/kg for nuts and 0.05 and 0.1 microg/kg for culinary spices and cereal products. The concentrations of aflatoxins in 86 samples of foods from market were below the permissible maximum levels legally binding. PMID:18246653

  14. Identification of highly brominated analogues of Q1 in marine mammals.

    Science.gov (United States)

    Teuten, Emma L; Pedler, Byron E; Hangsterfer, Alexandra N; Reddy, Christopher M

    2006-11-01

    Three novel halogenated organic compounds (HOCs) have been identified in the blubber of marine mammals from coastal New England with the molecular formulae C(9)H(3)N(2)Br(6)Cl, C(9)H(3)N(2)Br(7), and C(9)H(4)N(2)Br(5)Cl. They were identified using high and low resolution gas chromatography mass spectrometry (GCMS) and appear to be highly brominated analogues of Q1, a heptachlorinated HOC suspected to be naturally produced. These compounds were found in Atlantic white sided dolphin (Lagenorhynchus acutus), bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena), beluga whale (Delphinapterus leucas), fin whale (Balaenoptera physalus), grey seal (Halichoerus grypus), harp seal (Phoca groenlandica) and a potential food source (Loligo pealei) with concentrations as high as 2.7 microg/g (lipid weight). The regiospecificity of C(9)H(3)N(2)Br(6)Cl is suggestive of a biogenic origin. Debromination of C(9)H(3)N(2)Br(6)Cl may be significant in the formation of C(9)H(4)N(2)Br(5)Cl. PMID:16517037

  15. Photochemical transformation of five novel brominated flame retardants: Kinetics and photoproducts.

    Science.gov (United States)

    Zhang, Ya-Nan; Chen, Jingwen; Xie, Qing; Li, Yingjie; Zhou, Chengzhi

    2016-05-01

    Many novel brominated flame retardants (NBFRs) are used as substitutes of polybrominated diphenyl ethers (PBDEs) in recent years. However, little is known about their phototransformation behavior, which may influence the environmental fate of these chemicals. In this study, photochemical behavior of five NBFRs, allyl-2,4,6-tribromophenyl ether (ATE), 2-bromoallyl-2,4,6-tribromophenyl ether (BATE), 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ) was investigated. Results show all the five NBFRs can undergo photochemical transformation under simulated sunlight irradiation. Quantum yields (Φ) of the five NBFRs varied from 0.012 of TTBP-TAZ in hexane to 0.091 of BTBPE in methanol. Half-lives (t1/2) relevant with solar irradiation of these NBFRs were estimated using the determined Φ, and the values are 1.5-12.0 d in summer and 17.1-165.0 d in winter. Debrominated and ether bond cleavage products were identified in the phototransformation of DPTE and BTBPE. Debromination on the phenyl is a main phototransformation pathway for DPTE, and both debromination and ether bond cleavage are main phototransformation pathways for BTBPE. This study is helpful to better understand the phototransformation behavior of the NBFRs. PMID:26796587

  16. Nickel foam and carbon felt applications for sodium polysulfide/bromine redox flow battery electrodes

    International Nuclear Information System (INIS)

    The first use of nickel foam (NF) as electrocatalytic negative electrode in a polysulfide/bromine battery (PSB) is described. The performance of a PSB employing NF and polyacrylonitrile (PAN)-based carbon felt (CF) as negative and positive electrode materials, respectively, was evaluated by constant current charge-discharge tests in a single cell. Charge/discharge curves of the cell, positive and negative electrodes show that the rapid fall in cell voltage is due to the drop of positive potential caused by depletion of Br2 dissolved in the catholyte at the end of discharge. Cell voltage efficiency was limited by the relatively high internal ohmic resistance drop (iR drop). Polarization curves indicated that both NF and CF have excellent catalytic activity for the positive and negative redox reactions of PSB. The average energy efficiency of the single cell designed in this work could be as high as 77.2% at 40 mA cm-2 during 48 charge-discharge cycles

  17. Identification of highly brominated analogues of Q1 in marine mammals

    International Nuclear Information System (INIS)

    Three novel halogenated organic compounds (HOCs) have been identified in the blubber of marine mammals from coastal New England with the molecular formulae C9H3N2Br6Cl, C9H3N2Br7, and C9H4N2Br5Cl. They were identified using high and low resolution gas chromatography mass spectrometry (GCMS) and appear to be highly brominated analogues of Q1, a heptachlorinated HOC suspected to be naturally produced. These compounds were found in Atlantic white sided dolphin (Lagenorhynchus acutus), bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena), beluga whale (Delphinapterus leucas), fin whale (Balaenoptera physalus), grey seal (Halichoerus grypus), harp seal (Phoca groenlandica) and a potential food source (Loligo pealei) with concentrations as high as 2.7 μg/g (lipid weight). The regiospecificity of C9H3N2Br6Cl is suggestive of a biogenic origin. Debromination of C9H3N2Br6Cl may be significant in the formation of C9H4N2Br5Cl. - Three novel bioaccumulated compounds were identified as C9H3N2Br6Cl, C9H3N2Br7 and C9H4N2Br5Cl

  18. Is cloud seeding in coastal Antarctica linked to bromine and nitrate variability in snow?

    International Nuclear Information System (INIS)

    Considering the significance of methanesulfonate (MSA) in the sulfur cycle and global climate, we analyzed MSA and other ionic species in snow from the coastal Larsemann Hills, East Antarctica. MSA concentrations recorded were high (0.58 ± 0.7 μM) with ice-cap regions showing significantly higher concentrations (df = 10, p 2 cells l-1) with subsequent production of brominated compounds. The consequent elevated Br- (3.2 ± 2.2 μM) in the ice-cap region could result in the release of Br atoms through photoactivated reactions on aerosols and the snow surface. Activated Br atoms in the atmosphere could react with ozone leading to BrO enhancement with subsequent dimethylsulfide (DMS) oxidation and production of sulfur aerosols. Since BrO based DMS oxidation is much faster than the OH/NO3 pathway, elevated Br- in ice-cap snow could contribute more than ice-free sites towards formation of cloud condensation nuclei at the expense of ozone.

  19. On temperate sources of bromoform and other reactive organic bromine gases

    Science.gov (United States)

    Carpenter, L. J.; Liss, P. S.

    2000-08-01

    Current estimates of annual bromoform production by temperate marine algae underestimate, by at least an order of magnitude, the flux required to sustain atmospheric concentrations. In the light of recent evidence of the potential of bromoform to deplete upper-tropospheric/lower-stratospheric ozone, such a substantial discrepancy in global emission rates is of considerable concern. Here we present new information on air and seawater CHBr3, CH2Br2, and CHBr2Cl concentrations in the coastal east Atlantic and review previous data from widespread locations which suggest that concentrations and ratios of reactive organobromines are consistent with marine macroalgal emissions. Detailed reviews of algal halocarbon emissions and biomass estimates imply that macroalgae produce around 70% of the world's bromoform, rather than only ˜20% as previously thought, and that the underestimation was most likely caused by over conservative biomass estimates. Our total global source strength estimate of 2.2×1011 g CHBr3 yr-1 agrees well with recent calculations derived from atmospheric data. Given the dominant role of macroalgae in producing bromoform, the effect of changing climate and environment on seaweed populations and consequent effect on biogenic bromine emissions should be investigated.

  20. Brominated flame retardants in Chinese air before and after the phase out of polybrominated diphenyl ethers

    Science.gov (United States)

    Li, Wen-Long; Qi, Hong; Ma, Wan-Li; Liu, Li-Yan; Zhang, Zhi; Mohammed, Mohammed O. A.; Song, Wei-Wei; Zhang, Zifeng; Li, Yi-Fan

    2015-09-01

    Brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs) and novel non-BDE flame retardants (NBFRs), were analyzed in Chinese air during China's POPs Soil and Air Monitoring Program Phase I (SAMP-I) and Phase II (SAMP-II). The levels of Σ12PBDEs and Σ6NBFRs in urban sites were significantly higher than those in rural sites and background sites. The higher detection rate and concentrations of high molecular weight PBDEs and NBFRs in Phase II indicated the changing of the commercial pattern of BFRs after the phase out of PBDEs in China. Temperature was the major factor affecting the seasonal variations of molecular weight BFRs in atmosphere. A significant correlation between BFRs concentration and gross domestic product (GDP) was observed, with the GDP parameter explained 59.4% and 72.7% of the total variability for Octa-BDEs and low molecular weight NBFRs, respectively. Our findings indicated an evolving commercial usage of BFRs from SAMP-I to SAMP-II, i.e. shifting from lower molecular weight to higher molecular weight congeners in China.

  1. A study of the presence of brominated flame retardants in Australian fauna

    Energy Technology Data Exchange (ETDEWEB)

    Symons, R.; Burniston, D.; Piro, N.; Stevenson, G.; Yates, A. [Australian Government Analytical Laboratories, Sydney (Australia)

    2004-09-15

    Brominated flame retardants, in particular polybrominated diphenyl ethers (PBDEs) gained prominence in the late nineties when Noren et al. reported an exponential increase in PBDE levels found in Swedish mothers milk over a quarter of a century period with an associated decrease in levels of dioxin-like compounds. PBDEs have since become exceptionally widely studied being detected in most environmental compartments and food as well as human tissues. Only limited information on the distribution if PBDEs is available for the Southern Hemisphere, however, elevated levels of PBDEs in pork fat were detected during the routine screening for organochlorine pesticide residues. More recently an investigation of breast milk for PBDE levels also demonstrated that levels were comparable with those in the Northern Hemisphere. BFRs are not manufactured in Australia but it has been estimated that over 500 tonnes are imported yearly of which 340 tonnes are PBDEs. In addition, the amount of PBDEs that are contained in imported articles used both in domestic and industrial applications is unknown. In this paper, we report levels of PBDEs in a range of different Australian fauna that show that these POPs have indeed become widely distributed both in terms of the types of the fauna but also the levels determined.

  2. Two herbivore-induced cytochrome P450 enzymes CYP79D6 and CYP79D7 catalyze the formation of volatile aldoximes involved in poplar defense.

    Science.gov (United States)

    Irmisch, Sandra; McCormick, Andrea Clavijo; Boeckler, G Andreas; Schmidt, Axel; Reichelt, Michael; Schneider, Bernd; Block, Katja; Schnitzler, Jörg-Peter; Gershenzon, Jonathan; Unsicker, Sybille B; Köllner, Tobias G

    2013-11-01

    Aldoximes are known as floral and vegetative plant volatiles but also as biosynthetic intermediates for other plant defense compounds. While the cytochrome P450 monooxygenases (CYP) from the CYP79 family forming aldoximes as biosynthetic intermediates have been intensively studied, little is known about the enzymology of volatile aldoxime formation. We characterized two P450 enzymes, CYP79D6v3 and CYP79D7v2, which are involved in herbivore-induced aldoxime formation in western balsam poplar (Populus trichocarpa). Heterologous expression in Saccharomyces cerevisiae revealed that both enzymes produce a mixture of different aldoximes. Knockdown lines of CYP79D6/7 in gray poplar (Populus × canescens) exhibited a decreased emission of aldoximes, nitriles, and alcohols, emphasizing that the CYP79s catalyze the first step in the formation of a complex volatile blend. Aldoxime emission was found to be restricted to herbivore-damaged leaves and is closely correlated with CYP79D6 and CYP79D7 gene expression. The semi-volatile phenylacetaldoxime decreased survival and weight gain of gypsy moth (Lymantria dispar) caterpillars, suggesting that aldoximes may be involved in direct defense. The wide distribution of volatile aldoximes throughout the plant kingdom and the presence of CYP79 genes in all sequenced genomes of angiosperms suggest that volatile formation mediated by CYP79s is a general phenomenon in the plant kingdom. PMID:24220631

  3. Expression pattern and functional analysis of a MADS-box gene M79 from rice

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using a degenerated primer and a T-primer, a MADS-box gene, M79,was amplified by RT-PCR from rice fluorescence at meiosis stage and then cloned. Sequence analysis shows that M79 shares 98.2% homology with OsMADS7 at DNA level while only 92% at the amino acid level. The transcript of M79 possesses five different polyadenylation sites. Only a single copy of M79 gene has been found in rice genome, which is located on chromosome 8. M79 is expressed specifically in flower organs, from pre-meiosis stage through pollen maturation. Ectopic expression of M79 in T0 and T1 transgenic rice results in early-flowering, implying that M79 is involved in controlling the flowering time. In the same time, M79 may be involved in controlling the branching process to make more flower buds.

  4. Modification of radiation response in V79 cells with solcoseryl

    International Nuclear Information System (INIS)

    Solcoseryl is a deproteinized extract of calf serum which has been used for various purposes. It has been shown to simulate wound healing, to protect against carbon monoxide poisoning and to prevent teratogenic effects of cyclosphosphamide in mice. In addition, it has been reported to be a radiation protector and to modify radiation response in patients undergoing radiation treatment. The present study attempted to assess the effect of Solcoseryl on V79 cell survival and DNA damage after gamma irradiation. WR-1065 (4mM) was tested for comparative purpose. DNA damage was assayed using the alkaline elution technique while cell survival was determined in vitro using a standard clongenic assay. The results indicate that Solcoseryl doses protect against single-strand DNA breaks (SSB) but has little if any protective effect on cell survival. WR-1065- however, protects against both SSB and survival after gamma irradiation

  5. The poetic structure and strategy of Psalm 79

    Directory of Open Access Journals (Sweden)

    Phil J Botha

    2004-10-01

    Full Text Available This paper endeavours to analyse Psalm 79 as a poetic composition and� an ideological document. From the analysis, it seems that the psalm primarily served a Judaean community of believers as a means of coping with their feelings of indignation, shame, and frustration some time after the destruction� of� the temple in Jerusalem. The argument used is that Yahweh�s efforts to exact punishment from his people for their contravening stipulations of the covenant have become detrimental to his honour. It suggests that it is time for Yahweh to act on behalf� of his honour. The psalm simultaneously seems to have served as a confession of the community�s faith that Yahweh can and will intervene on their behalf.

  6. Morphological changes of V-79 cells after equinatoxin II treatment.

    Science.gov (United States)

    Batista, U; Jezernik, K

    1992-02-01

    Morphological observations on the V-79-379 A cells after treatment with equinatoxin II (EqT II), isolated from the sea anemone Actina equina L., and fetal calf serum (FCS) treated toxin were examined by transmission electron microscopy. Our results showed that the cells incubated with FCS treated EqT II were almost ultrastructurally unaltered. When the cells were treated with low concentrations of EqT II alone cell ultrastructure was altered with the evidence of numerous blebs and decreased microvilli number on the cell surface and appearance of numerous vesicles in the Golgi regions. High concentrations of EqT II caused disintegration of plasmalemma and intracellular membranes as well as degradation of cytosol. PMID:1348018

  7. High Rydberg resonances in dielectronic recombination of pb(79+).

    Science.gov (United States)

    Brandau, C; Bartsch, T; Hoffknecht, A; Knopp, H; Schippers, S; Shi, W; Müller, A; Grün, N; Scheid, W; Steih, T; Bosch, F; Franzke, B; Kozhuharov, C; Mokler, P H; Nolden, F; Steck, M; Stöhlker, T; Stachura, Z

    2002-07-29

    Dielectronic recombination resonances of Pb (79+) associated with 2s(1/2)-->2p(1/2) excitations were measured at the heavy-ion storage ring ESR at GSI. The fine structure of the energetically lowest resonance manifold Pb (78+)(1s(2)2p(1/2)20l(j)) at around 18 eV could partially be resolved, and rate coefficients on an absolute scale were obtained. A comparison of the experimental data with results of a fully relativistic theoretical approach shows that high-angular-momentum components up to j=31/2 significantly contribute to the total resonance strength demonstrating the necessity to revise the widespread notion of negligible high-angular-momentum contributions at least for very highly charged ions. PMID:12144440

  8. Radiological safety evaluation report for NUWAX-79 exercise

    International Nuclear Information System (INIS)

    An analysis of the radiological safety of the NUWAX-79 exercise to be conducted on the Nevada Test Site in April 1979 is given. An evaluation of the radiological safety to the participants is made using depleted uranium (D-38) in mock weapons parts, and 223Ra and its daughters as a radioactive contaminant of equipment and terrain. The radiological impact to offsite persons is also discussed, particularly for people living at Lathrop Wells, Nevada, which is located 7 miles south of the site proposed for the exercise. It is the conclusion of this evaluation that the potential radiological risk of this exercise is very low, and that no individual should receive exposure to radioactivity greater than one-tenth of the level permitted under current federal radiation exposure guidelines

  9. Greenland ice core evidence of the 79 AD Vesuvius eruption

    Directory of Open Access Journals (Sweden)

    C. Barbante

    2013-06-01

    Full Text Available Volcanic tephra are independent age horizons and can synchronize strata of various paleoclimate records including ice and sediment cores. The Holocene section of the Greenland Ice Core Project (GRIP ice core is dated by multi-parameter annual layer counting, and contains peaks in acidity, SO42− and microparticle concentrations at a depth of 429.1 to 429.3 m, which have not previously been definitively ascribed to a volcanic eruption. Here, we identify tephra particles and determine that volcanic shards extracted from a depth of 429.3 m in the GRIP ice core are likely due to the 79 AD Vesuvius eruption. The chemical composition of the tephra particles is consistent with the K-phonolitic composition of the Vesuvius juvenile ejecta and differs from the chemical composition of other major eruptions (≥ VEI 4 between 50–100 AD.

  10. The role of bromine and chlorine chemistry for arctic ozone depletion events in Ny-Ålesund and comparison with model calculations

    Directory of Open Access Journals (Sweden)

    M. Martinez

    Full Text Available During the Arctic Tropospheric Ozone Chemistry (ARCTOC campaigns at Ny-Ålesund, Spitsbergen, the role of halogens in the depletion of boundary layer ozone was investigated. In spring 1995 and 1996 up to 30 ppt bromine monoxide were found whenever ozone decreased from normal levels of about 40 ppb. Those main trace gases and others were specifically followed in the UV-VIS spectral region by differential optical absorption spectroscopy (DOAS along light paths running between 20 and 475 m a.s.l.. The daily variation of peroxy radicals closely followed the ozone photolysis rate J(O3(O1D in the absence of ozone depletion most of the time. However, during low ozone events this close correlation was no longer found because the measurement of radicals by chemical amplification (CA turned out to be sensitive to peroxy radicals and ClOx. Large CA signals at night can sometimes definitely be assigned to ClOx and reached up to 2 ppt. Total bromine and iodine were both stripped quantitatively from air by active charcoal traps and measured after neutron activation of the samples. Total bromine increased from background levels of about 15 ppt to a maximum of 90 ppt during an event of complete ozone depletion. For the spring season a strong source of bromine is identified in the pack ice region according to back trajectories. Though biogenic emission sources cannot be completely ruled out, a primary activation of halogenides by various oxidants seems to initiate an efficient autocatalytic process, mainly driven by ozone and light, on ice and perhaps on aerosols. Halogenides residing on pack ice surfaces are continuously oxidised by hypohalogenous acids releasing bromine and chlorine into the air. During transport and especially above open water this air mixes with upper layer pristine air. As large quantities of bromine, often in the form of BrO, have been observed at polar sunrise also around Antarctica, its release

  11. 7 CFR 3.79 - Review of USDA records related to the debt.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Review of USDA records related to the debt. 3.79 Section 3.79 Agriculture Office of the Secretary of Agriculture DEBT MANAGEMENT Federal Salary Offset § 3.79 Review of USDA records related to the debt. (a) Notification by employee. An employee who...

  12. 28 CFR 79.12 - Criteria for eligibility for claims relating to leukemia.

    Science.gov (United States)

    2010-07-01

    ... relating to leukemia. 79.12 Section 79.12 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE RADIATION EXPOSURE COMPENSATION ACT Eligibility Criteria for Claims Relating to Leukemia § 79.12 Criteria for eligibility for claims relating to leukemia. To establish eligibility...

  13. 26 CFR 1.79-2 - Exceptions to the rule of inclusion.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Exceptions to the rule of inclusion. 1.79-2... Exceptions to the rule of inclusion. (a) In general. (1) Section 79(b) provides exceptions for the cost of... to the rule of inclusion set forth in section 79(a), but determined without regard to the amount...

  14. 41 CFR 102-79.105 - What is the Integrated Workplace?

    Science.gov (United States)

    2010-07-01

    ... Workplace? 102-79.105 Section 102-79.105 Public Contracts and Property Management Federal Property... UTILIZATION OF SPACE Assignment and Utilization of Space Integrated Workplace § 102-79.105 What is the Integrated Workplace? The Integrated Workplace, developed by the GSA Office of Governmentwide Policy, is...

  15. 45 CFR 79.40 - Stays ordered by the Department of Justice.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Stays ordered by the Department of Justice. 79.40 Section 79.40 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROGRAM FRAUD CIVIL REMEDIES § 79.40 Stays ordered by the Department of Justice. If at any time the Attorney...

  16. 40 CFR 86.309-79 - Sampling and analytical system; schematic drawing.

    Science.gov (United States)

    2010-07-01

    ...; schematic drawing. 86.309-79 Section 86.309-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Procedures § 86.309-79 Sampling and analytical system; schematic drawing. (a) Any variation from the... only with prior approval by the Administrator. (b) Schematic drawing. (1) An example of a sampling...

  17. 33 CFR 151.79 - Operating requirements: Discharge of sewage within Antarctica.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Operating requirements: Discharge of sewage within Antarctica. 151.79 Section 151.79 Navigation and Navigable Waters COAST GUARD... Pollution and Sewage § 151.79 Operating requirements: Discharge of sewage within Antarctica. (a) A...

  18. 33 CFR 173.79 - Expiration of Coast Guard certificate of number.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Expiration of Coast Guard certificate of number. 173.79 Section 173.79 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Certificate of Number § 173.79 Expiration of Coast Guard certificate of number. A certificate of number...

  19. 41 CFR 102-79.110 - What Integrated Workplace policy must Federal agencies strive to promote?

    Science.gov (United States)

    2010-07-01

    ... Workplace policy must Federal agencies strive to promote? 102-79.110 Section 102-79.110 Public Contracts and... Integrated Workplace § 102-79.110 What Integrated Workplace policy must Federal agencies strive to promote... maximize his or her productivity and satisfaction; (e) Are comfortable, efficient, and...

  20. Novel analytical approach for brominated flame retardants based on the use of gas chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry with emphasis in highly brominated congeners.

    Science.gov (United States)

    Portolés, Tania; Sales, Carlos; Gómara, Belén; Sancho, Juan Vicente; Beltrán, Joaquim; Herrero, Laura; González, María José; Hernández, Félix

    2015-10-01

    The analysis of brominated flame retardants (BFRs) commonly relies on the use of gas chromatography coupled to mass spectrometry (GC-MS) operating in electron ionization (EI) and electron capture negative ionization (ECNI) modes using quadrupole, triple quadrupole, ion trap, and magnetic sector analyzers. However, these brominated contaminants are examples of compounds for which a soft and robust ionization technique might be favorable since they show high fragmentation in EI and low specificity in ECNI. In addition, the low limits of quantification (0.01 ng/g) required by European Commission Recommendation 2014/118/EU on the monitoring of traces of BFRs in food put stress on the use of highly sensitive techniques/methods. In this work, a new approach for the extremely sensitive determination of BFRs taking profit of the potential of atmospheric pressure chemical ionization (APCI) combined with GC and triple quadrupole (QqQ) mass analyzer is proposed. The objective was to explore the potential of this approach for the BFRs determination in samples at pg/g levels, taking marine samples and a cream sample as a model. Ionization and fragmentation behavior of 14 PBDEs (congeners 28, 47, 66, 85, 99, 100, 153, 154, 183, 184, 191, 196, 197, and 209) and two novel BFRs, decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), in the GC-APCI-MS system has been investigated. The formation of highly abundant (quasi) molecular ion was the main advantage observed in relation to EI. Thus, a notable improvement in sensitivity and specificity was observed when using it as precursor ion in tandem MS. The improved detectability (LODs < 10 fg) achieved when using APCI compared to EI has been demonstrated, which is especially relevant for highly brominated congeners. Analysis of samples from an intercomparison exercise and samples from the marine field showed the potential of this approach for the reliable identification and quantification at very low

  1. Emissions of Bromine and Iodine from the Marine Environment in New Zealand

    Science.gov (United States)

    Martinez-Aviles, M.; Kreher, K.; Johnston, P. V.; Hay, T.; Thomas, A.; Schofield, R.

    2009-12-01

    of determining coastal sites where high active halogen release could be observed. The selected sites had high biomass concentration of marine algae that would be exposed by low tides. Local macro algae type, tidal height, sunlight, temperature, and wind speed were recorded and correlated to the resulting data in order to better understand the environmental factors that modulate the emissions of halogen oxides from the marine environment to the troposphere. Results of this multi-disciplinary approach to studying brominated VSLS and their atmospheric implications are presented. As well, the chemical processes taking place and producing these halogen oxides are discussed in a thorough manner. This study contributes to a better understanding of the origin of bromine and iodine in the lowermost atmosphere (i.e. marine boundary layer). Particularly, the role that natural emissions of halogenated VSLS from the ocean may play in the halogen budget of the lower atmosphere is addressed by quantitatively understanding key links in this chain so that its potential future impacts on atmospheric chemistry, surface UV radiation, and the biosphere can be thoroughly assessed.

  2. The Reaction between Bromine and the Water Dimer and the Highly Exothermic Reverse Reaction.

    Science.gov (United States)

    Li, Guoliang; Wang, Hui; Li, Qian-Shu; Xie, Yaoming; Schaefer, Henry F

    2016-01-15

    The entrance complex, transition state, and exit complex for the bromine atom plus water dimer reaction Br + (H2O)2 → HBr + (H2O)OH and its reverse reaction have been investigated using the CCSD(T) method with correlation consistent basis sets up to cc-pVQZ-PP. Based on the CCSD(T)/cc-pVQZ-PP results, the reaction is endothermic by 31.7 kcal/mol. The entrance complex Br⋯(H2O)2 is found to lie 6.5 kcal/mol below the separated reactants. The classical barrier lies 28.3 kcal/mol above the reactants. The exit complex HBr⋯(H2O)OH is bound by 6.0 kcal/mol relative to the separated products. Compared with the corresponding water monomer reaction Br + H2 O → HBr + OH, the second water molecule lowers the relative energies of the entrance complex, transition state, and exit complex by 3.0, 3.8, and 3.7 kcal/mol, respectively. Both zero-point vibrational energies and spin-orbit coupling effects make significant changes to the above classical energetics. Including both effects, the predicted energies relation to separated Br + (H2O)2 are -3.0 kcal/mol [Br···(H2O)2 ], 28.2 kcal/mol [transition state], 26.4 kcal/mol [HBr···(H2O)OH], and 30.5 kcal/mol [separated HBr + (H2O)OH]. The potential energy surface for the Br + (H2O)2 reaction is related to that for the valence isoelectronic Cl + (H2O)2 system but radically different from the F + (H2O)2 system. PMID:26040856

  3. Reductive dehalogenation of brominated phenolic compounds by microorganisms associated with the marine sponge Aplysina aerophoba.

    Science.gov (United States)

    Ahn, Young-Beom; Rhee, Sung-Keun; Fennell, Donna E; Kerkhof, Lee J; Hentschel, Ute; Häggblom, Max M

    2003-07-01

    Marine sponges are natural sources of brominated organic compounds, including bromoindoles, bromophenols, and bromopyrroles, that may comprise up to 12% of the sponge dry weight. Aplysina aerophoba sponges harbor large numbers of bacteria that can amount to 40% of the biomass of the animal. We postulated that there might be mechanisms for microbially mediated degradation of these halogenated chemicals within the sponges. The capability of anaerobic microorganisms associated with the marine sponge to transform haloaromatic compounds was tested under different electron-accepting conditions (i.e., denitrifying, sulfidogenic, and methanogenic). We observed dehalogenation activity of sponge-associated microorganisms with various haloaromatics. 2-Bromo-, 3-bromo-, 4-bromo-, 2,6-dibromo-, and 2,4,6-tribromophenol, and 3,5-dibromo-4-hydroxybenzoate were reductively debrominated under methanogenic and sulfidogenic conditions with no activity observed in the presence of nitrate. Monochlorinated phenols were not transformed over a period of 1 year. Debromination of 2,4,6-tribromophenol, and 2,6-dibromophenol to 2-bromophenol was more rapid than the debromination of the monobrominated phenols. Ampicillin and chloramphenicol inhibited activity, suggesting that dehalogenation was mediated by bacteria. Characterization of the debrominating methanogenic consortia by using terminal restriction fragment length polymorphism (TRFLP) and denaturing gradient gel electrophoresis analysis indicated that different 16S ribosomal DNA (rDNA) phylotypes were enriched on the different halogenated substrates. Sponge-associated microorganisms enriched on organobromine compounds had distinct 16S rDNA TRFLP patterns and were most closely related to the delta subgroup of the proteobacteria. The presence of homologous reductive dehalogenase gene motifs in the sponge-associated microorganisms suggested that reductive dehalogenation might be coupled to dehalorespiration. PMID:12839794

  4. Bromination vis-a-vis chlorination as a biocide feasibility study

    International Nuclear Information System (INIS)

    friendly. This paper highlights the brief details on the feasibility studies carried out on bromination. (author)

  5. The NOx dependence of bromine chemistry in the Arctic atmospheric boundary layer

    Science.gov (United States)

    Custard, K. D.; Thompson, C. R.; Pratt, K. A.; Shepson, P. B.; Liao, J.; Huey, L. G.; Orlando, J. J.; Weinheimer, A. J.; Apel, E.; Hall, S. R.; Flocke, F.; Mauldin, L.; Hornbrook, R. S.; Pöhler, D.; S., General; Zielcke, J.; Simpson, W. R.; Platt, U.; Fried, A.; Weibring, P.; Sive, B. C.; Ullmann, K.; Cantrell, C.; Knapp, D. J.; Montzka, D. D.

    2015-09-01

    Arctic boundary layer nitrogen oxides (NOx = NO2 + NO) are naturally produced in and released from the sunlit snowpack and range between 10 to 100 pptv in the remote background surface layer air. These nitrogen oxides have significant effects on the partitioning and cycling of reactive radicals such as halogens and HOx (OH + HO2). However, little is known about the impacts of local anthropogenic NOx emission sources on gas-phase halogen chemistry in the Arctic, and this is important because these emissions can induce large variability in ambient NOx and thus local chemistry. In this study, a zero-dimensional photochemical kinetics model was used to investigate the influence of NOx on the unique springtime halogen and HOx chemistry in the Arctic. Trace gas measurements obtained during the 2009 OASIS (Ocean - Atmosphere - Sea Ice - Snowpack) field campaign at Barrow, AK were used to constrain many model inputs. We find that elevated NOx significantly impedes gas-phase halogen radical-based depletion of ozone, through the production of a variety of reservoir species, including HNO3, HO2NO2, peroxyacetyl nitrate (PAN), BrNO2, ClNO2 and reductions in BrO and HOBr. The effective removal of BrO by anthropogenic NOx was directly observed from measurements conducted near Prudhoe Bay, AK during the 2012 Bromine, Ozone, and Mercury Experiment (BROMEX). Thus, while changes in snow-covered sea ice attributable to climate change may alter the availability of molecular halogens for ozone and Hg depletion, predicting the impact of climate change on polar atmospheric chemistry is complex and must take into account the simultaneous impact of changes in the distribution and intensity of anthropogenic combustion sources. This is especially true for the Arctic, where NOx emissions are expected to increase because of increasing oil and gas extraction and shipping activities.

  6. Formation and emission of brominated dioxins and furans during secondary aluminum smelting processes.

    Science.gov (United States)

    Wang, Mei; Liu, Guorui; Jiang, Xiaoxu; Li, Sumei; Liu, Wenbin; Zheng, Minghui

    2016-03-01

    Secondary aluminum smelting (SAl) processes have previously been found to be important sources of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs). It is crucial that the key factors that influence the formation and emission of PBDD/Fs are identified to allow techniques for decreasing PBDD/F emissions during SAl processes to be developed. In this study, stack gas samples were collected from four typical secondary aluminum smelters that used different raw materials, and the samples were analyzed to allow differences between PBDD/F emissions from different SAl plants to be assessed. The composition of the raw materials was found to be one of the key factors influencing the amounts of PBDD/Fs emitted. The PBDD/F emission factors (per tonne of aluminum produced) for the plants using 100% (Plant1), 80% (Plant2), and 50% (Plant3) dirty aluminum scrap in the raw material feed were 180, 86, and 14 μg t(-1), respectively. The amounts of PBDD/Fs emitted at different stages of the smelting process (feeding-fusion, refining, and casting) were compared, and the feeding-fusion stage was found to be the main stage in which PBDD/Fs were formed and emitted. Effective aluminum scrap pretreatments could significantly decrease PBDD/F emissions. Much higher polybrominated dibenzofuran concentrations than polybrominated dibenzo-p-dioxin concentrations were found throughout the SAl process. The more-brominated congeners (including octabromodibenzo-p-dioxin, octabromodibenzofuran, heptabromodibenzo-p-dioxins, and heptabromodibenzofurans) were the dominant contributors to the total PBDD/F concentrations. The results could help in the development of techniques and strategies for controlling PBDD/F emissions during metallurgical processes. PMID:26706932

  7. Fabric phase sorptive extraction: Two practical sample pretreatment techniques for brominated flame retardants in water.

    Science.gov (United States)

    Huang, Guiqi; Dong, Sheying; Zhang, Mengfei; Zhang, Haihan; Huang, Tinglin

    2016-09-15

    Sample pretreatment is the critical section for residue monitoring of hazardous pollutants. In this paper, using the cellulose fabric as host matrix, three extraction sorbents such as poly (tetrahydrofuran) (PTHF), poly (ethylene glycol) (PEG) and poly (dimethyldiphenylsiloxane) (PDMDPS), were prepared on the surface of the cellulose fabric. Two practical extraction techniques including stir bar fabric phase sorptive extraction (stir bar-FPSE) and magnetic stir fabric phase sorptive extraction (magnetic stir-FPSE) have been designed, which allow stirring of fabric phase sorbent during the whole extraction process. In the meantime, three brominated flame retardants (BFRs) [tetrabromobisphenol A (TBBPA), tetrabromobisphenol A bisallylether (TBBPA-BAE), tetrabromobisphenol A bis(2,3-dibromopropyl)ether (TBBPA-BDBPE)] in the water sample were selected as model analytes for the practical evaluation of the proposed two techniques using high-performance liquid chromatography (HPLC). Moreover, various experimental conditions affecting extraction process such as the type of fabric phase, extraction time, the amount of salt and elution conditions were also investigated. Due to the large sorbent loading capacity and unique stirring performance, both techniques possessed high extraction capability and fast extraction equilibrium. Under the optimized conditions, high recoveries (90-99%) and low limits of detection (LODs) (0.01-0.05 μg L(-1)) were achieved. In addition, the reproducibility was obtained by evaluating the intraday and interday precisions with relative standard deviations (RSDs) less than 5.1% and 6.8%, respectively. The results indicated that two pretreatment techniques were promising and practical for monitoring of hazardous pollutants in the water sample. Due to low solvent consumption and high repeated use performance, proposed techniques also could meet green analytical criteria. PMID:27300591

  8. Accurate determination and certification of bromine in plastic by isotope dilution inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ohata, Masaki, E-mail: m-oohata@aist.go.jp; Miura, Tsutomu

    2014-07-21

    Highlights: • Accurate analytical method of Br in plastic was studied by isotope dilution ICPMS. • A microwave acid digestion using quartz vessel was suitable for Br analysis. • Sample dilution by NH{sub 3} solution could remove memory effect for ICPMS measurement. • The analytical result of the ID-ICPMS showed consistency with that of INAA. • The ID-ICPMS developed could apply to certification of Br in candidate plastic CRM. - Abstract: The accurate analytical method of bromine (Br) in plastic was developed by an isotope dilution inductively coupled plasma mass spectrometry (ID-ICPMS). The figures of merit of microwave acid digestion procedures using polytetrafluoroethylene (PTFE) or quartz vessels were studied and the latter one was suitable for Br analysis since its material was free from Br contamination. The sample dilution procedures using Milli-Q water or ammonium (NH{sub 3}) solution were also studied to remove memory effect for ICPMS measurement. Although severe memory effect was observed on Milli-Q water dilution, NH{sub 3} solution could remove it successfully. The accuracy of the ID-ICPMS was validated by a certified reference material (CRM) as well as the comparison with the analytical result obtained by an instrumental neutron activation analysis (INAA) as different analytical method. From these results, the ID-ICPMS developed in the present study could be evaluated as accurate analytical method of Br in plastic materials and it could apply to certification of Br in candidate plastic CRM with respect to such regulations related to RoHS (restriction of the use of hazardous substances in electrical and electronics equipment) directive.

  9. Characterization of bromine-76-labelled 5-bromo-6-nitroquipazine for PET studies of the serotonin transporter

    Energy Technology Data Exchange (ETDEWEB)

    Lundkvist, Camilla E-mail: Lundkvis@shfj.cea.fr; Loc' h, Christian; Halldin, Christer; Bottlaender, Michel; Ottaviani, Michele; Coulon, Christine; Fuseau, Chantal; Mathis, Chester; Farde, Lars; Maziere, Bernard

    1999-07-01

    The development of suitable radioligands for brain imaging of the serotonin transporter is of great importance for the study of depression and other affective disorders. The potent and selective serotonin transporter ligand, 5-iodo-6-nitro-2-piperazinylquinoline, has been labelled with iodine-123 and used as a radioligand for single photon emission computerized tomography. To evaluate the potential of the bromine-76-labelled analogue, 5-bromo-6-nitroquipazine, as a radioligand for positron emission tomography (PET), its brain distribution and binding characteristics were examined in rats. In vivo brain distribution and ex vivo autoradiography demonstrated that [{sup 76}Br]5-bromo-6-nitroquipazine enters the brain rapidly. The regional brain distribution of [{sup 76}Br]5-bromo-6-nitroquipazine was consistent with the known distribution of serotonin transporters in the midbrain, pons, thalamus, striatum, and neocortex. Specific binding was inhibited by the selective serotonin reuptake inhibitor citalopram. The peripheral metabolism in plasma was rapid, but more than 90% of the radioactivity in brain represented unchanged radioligand 2 h postinjection (p.i.). A preliminary PET study was also performed in a baboon. Following the intravenous injection of [{sup 76}Br]5-bromo-6-nitroquipazine in a baboon, there was a conspicuous accumulation of radioactivity in thalamus, striatum, and pons. The radioactivity in these brain regions was 1.5 times higher than in the cerebellum at 3 h and 2.5-4 times higher at 24 h. A rapid metabolism of the radioligand in plasma was observed (38% unchanged after 5 min). The results indicate that [{sup 76}Br]5-bromo-6-nitroquipazine has potential for PET imaging of the serotonin transporter.

  10. Batch sorption experiments with iodine, bromine, strontium, sodium and cesium on Grimsel mylonite

    International Nuclear Information System (INIS)

    Promylonite surrounding the fracture at the migration site was not available in sufficient amounts, so mylonite from an adjacent fault zone was used. All the work has been carried out in glove boxes in a nitrogen atmosphere with very low O2 and CO2 levels. Mylonite was equilibrated with the natural Grimsel groundwater (NGW) prior to sorption experiments. The first series of sorption experiments was carried out without shaking. This caused sedimentation of the mylonite and led to slow kinetics. In the later experiments therefore, gentle, continuous agitation was used. No sorption of iodine and bromine on mylonite was observed under the experimental conditions used. It was observed that the sorption coefficient of 85Sr and 22Na were not affected by varying nuclide concentrations, provided these were kept much below their natural levels in NGW. This indicates that, in this nuclide concentration range, isotopic exchange takes place. Sorption coefficients did not vary with the rock/water ratio. Experiments with a bulky displacing cation suggested that some sodium ions were on less accessible internal sites and this could account for the slow kinetics for sodium. Further experiments with samples with smaller particle size confirmed this hypothesis. Batch sorption experiments on mylonite at initial cesium concentrations of between 3,2.10-8 and 5,0.10-4 M showed that sorption was reversible and non-linear; sorption coefficients were between 3800 and 21 ml/g. Increasing the potassium concentration in the solution led to reduced sorption of cesium, suggesting that Cs and K compete for the sorption sites. At the lowest Cs concentration used, sorption appears to be due to exchange with K at specific sites on mica, together with possible isotopic exchange. For these conditions and by making some assumptions, a Cs sorption coefficient for waters with different concentrations could be estimated. (author) 7 figs., 12 tabs., 42 refs

  11. Accurate determination and certification of bromine in plastic by isotope dilution inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Highlights: • Accurate analytical method of Br in plastic was studied by isotope dilution ICPMS. • A microwave acid digestion using quartz vessel was suitable for Br analysis. • Sample dilution by NH3 solution could remove memory effect for ICPMS measurement. • The analytical result of the ID-ICPMS showed consistency with that of INAA. • The ID-ICPMS developed could apply to certification of Br in candidate plastic CRM. - Abstract: The accurate analytical method of bromine (Br) in plastic was developed by an isotope dilution inductively coupled plasma mass spectrometry (ID-ICPMS). The figures of merit of microwave acid digestion procedures using polytetrafluoroethylene (PTFE) or quartz vessels were studied and the latter one was suitable for Br analysis since its material was free from Br contamination. The sample dilution procedures using Milli-Q water or ammonium (NH3) solution were also studied to remove memory effect for ICPMS measurement. Although severe memory effect was observed on Milli-Q water dilution, NH3 solution could remove it successfully. The accuracy of the ID-ICPMS was validated by a certified reference material (CRM) as well as the comparison with the analytical result obtained by an instrumental neutron activation analysis (INAA) as different analytical method. From these results, the ID-ICPMS developed in the present study could be evaluated as accurate analytical method of Br in plastic materials and it could apply to certification of Br in candidate plastic CRM with respect to such regulations related to RoHS (restriction of the use of hazardous substances in electrical and electronics equipment) directive

  12. Identification of highly brominated analogues of Q1 in marine mammals

    Energy Technology Data Exchange (ETDEWEB)

    Teuten, Emma L. [Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 (United States)]. E-mail: emma.teuten@plymouth.ac.uk; Pedler, Byron E. [Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 (United States)]. E-mail: bpedler@whoi.edu; Hangsterfer, Alexandra N. [Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 (United States)]. E-mail: ahangsterfer@whoi.edu; Reddy, Christopher M. [Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 (United States)]. E-mail: creddy@whoi.edu

    2006-11-15

    Three novel halogenated organic compounds (HOCs) have been identified in the blubber of marine mammals from coastal New England with the molecular formulae C{sub 9}H{sub 3}N{sub 2}Br{sub 6}Cl, C{sub 9}H{sub 3}N{sub 2}Br{sub 7}, and C{sub 9}H{sub 4}N{sub 2}Br{sub 5}Cl. They were identified using high and low resolution gas chromatography mass spectrometry (GCMS) and appear to be highly brominated analogues of Q1, a heptachlorinated HOC suspected to be naturally produced. These compounds were found in Atlantic white sided dolphin (Lagenorhynchus acutus), bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena), beluga whale (Delphinapterus leucas), fin whale (Balaenoptera physalus), grey seal (Halichoerus grypus), harp seal (Phoca groenlandica) and a potential food source (Loligo pealei) with concentrations as high as 2.7 {mu}g/g (lipid weight). The regiospecificity of C{sub 9}H{sub 3}N{sub 2}Br{sub 6}Cl is suggestive of a biogenic origin. Debromination of C{sub 9}H{sub 3}N{sub 2}Br{sub 6}Cl may be significant in the formation of C{sub 9}H{sub 4}N{sub 2}Br{sub 5}Cl. - Three novel bioaccumulated compounds were identified as C{sub 9}H{sub 3}N{sub 2}Br{sub 6}Cl, C{sub 9}H{sub 3}N{sub 2}Br{sub 7} and C{sub 9}H{sub 4}N{sub 2}Br{sub 5}Cl.

  13. Brominated flame retardants - Exposure and risk assessment for the general population.

    Science.gov (United States)

    Fromme, H; Becher, G; Hilger, B; Völkel, W

    2016-01-01

    Brominated flame retardants (BFRs) are a large group of different substances used in numerous products to prevent fire hazards. Some of them are persistent in the environment, accumulate in the food chain and are of toxicological concern, while for others current data are limited. Meanwhile, BFRs have been found in many environmental media, foods, and biota including humans. This review presents recent findings obtained from monitoring data in environmental media relevant for human exposure, as well as dietary exposure. In this context, concentrations in indoor and ambient air and in house dust are outlined. Furthermore, we summarize human biomonitoring data on BFR levels in blood and breast milk. Current estimates of the overall exposure of the general population using different relevant subsets are also addressed. All of these data are discussed in relation to currently available toxicological reference values used for risk assessment purposes. Obviously, the exposure of the general population varies considerably in different parts of the world and even within countries. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) show the highest intake during infancy. While the highest intake for BDE 47 for all groups was observed in the US, the total BDE 209 and HBCD intake was highest in the UK. For HBCD and all PBDEs except BDE 209, diet accounts for a large proportion of the total intake during infancy in all countries. With regard to toddlers and adults, the contribution of diet to total intake is high in Germany and the UK, while in the US, the high concentrations of PBDE in dust resulted in a notably smaller proportion of the intake being attributed to diet. PMID:26412400

  14. Feline coronavirus type II strains 79-1683 and 79-1146 originate from a double recombination between feline coronavirus type I and canine coronavirus

    NARCIS (Netherlands)

    Horzinek, M.C.; Herrewegh, A.A.; Rottier, P.J.M.; Groot, R.J. de

    1998-01-01

    Recent evidence suggests that the type II feline coronavirus (FCoV) strains 79-1146 and 79-1683 have arisen from a homologous RNA recombination event between FCoV type I and canine coronavirus (CCV). In both cases, the template switch apparently took place between the S and M genes, giving rise to r

  15. 78 FR 38922 - Foreign-Trade Zone 79-Tampa, Florida, Foreign-Trade Subzone 79C-Cutrale Citrus Juices USA, Inc...

    Science.gov (United States)

    2013-06-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE Foreign-Trade Zones Board Foreign-Trade Zone 79--Tampa, Florida, Foreign-Trade Subzone 79C--Cutrale Citrus Juices USA, Inc., Application for Additional Subzone Sites An application has been submitted to...

  16. Field and Satellite Observations of the Formation and Distribution of Arctic Atmospheric Bromine Above a Rejuvenated Sea Ice Cover

    Science.gov (United States)

    Nghiem, Son V.; Rigor, Ignatius G.; Richter, Andreas; Burrows, John P.; Shepson, Paul B.; Bottenheim, Jan; Barber, David G.; Steffen, Alexandra; Latonas, Jeff; Wang, Feiyue; Stern, Gary; Clemente-Colon, Pablo; Martin, Seelye; Hall, Dorothy K.; Kaleschke, Lars; Tackett, Philip; Neumann, Gregory; Asplin, Matthew G.

    2012-01-01

    Recent drastic reduction of the older perennial sea ice in the Arctic Ocean has resulted in a vast expansion of younger and saltier seasonal sea ice. This increase in the salinity of the overall ice cover could impact tropospheric chemical processes. Springtime perennial ice extent in 2008 and 2009 broke the half-century record minimum in 2007 by about one million km2. In both years seasonal ice was dominant across the Beaufort Sea extending to the Amundsen Gulf, where significant field and satellite observations of sea ice, temperature, and atmospheric chemicals have been made. Measurements at the site of the Canadian Coast Guard Ship Amundsen ice breaker in the Amundsen Gulf showed events of increased bromine monoxide (BrO), coupled with decreases of ozone (O3) and gaseous elemental mercury (GEM), during cold periods in March 2008. The timing of the main event of BrO, O3, and GEM changes was found to be consistent with BrO observed by satellites over an extensive area around the site. Furthermore, satellite sensors detected a doubling of atmospheric BrO in a vortex associated with a spiral rising air pattern. In spring 2009, excessive and widespread bromine explosions occurred in the same region while the regional air temperature was low and the extent of perennial ice was significantly reduced compared to the case in 2008. Using satellite observations together with a Rising-Air-Parcel model, we discover a topographic control on BrO distribution such that the Alaskan North Slope and the Canadian Shield region were exposed to elevated BrO, whereas the surrounding mountains isolated the Alaskan interior from bromine intrusion.

  17. Accumulation of chlorinated and brominated persistent toxic substances (PTS) and their relationship to testosterone suppression in Norway rats from Japan

    Energy Technology Data Exchange (ETDEWEB)

    Takasuga, T.; Senthilkumar, K. [Shimadzu Techno-Research Inc. (Japan); Ishizuka, M.; Fujita, S. [Graduate School of Veterinary Medicine, Hokkaido Univ. (Japan); Tanikawa, R. [Inst. of Tech., Ikari Corp. (Japan)

    2004-09-15

    Contamination of chlorinated/brominated persistent toxic substances (PTS) such as polychlorinated, -dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs), -biphenyls (PCBs), - organochlorine pesticides (OCPs) {l_brace}e.g., aldrin, dieldrin, endrin, chlordane compounds [cis/transchlordane, cis/trans-nonachlor, oxychlordane, heptachlor, heptachlor epoxide], hexachlorobenzene (HCB), 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDTs) and its metabolities [o,p/p,p'-DDD and DDE] and hexachlorocyclohexane (HCHs){r_brace} and -brominated diphenyl ethers (PBDEs) are considered to important class of chemicals due to persistence in nature, bioaccumulation potential and adverse health effects in wildlife and humans. Among South East Asian countries, Japan reported to contaminated with aforesaid chemicals with considerable amounts. There is no document reports contamination of PTS in wild animals, which in-habit near humans. Norway rat (NR) inhabits not only near human environment but also distributed worldwide. Especially, NR feeds on human waste and shelter in and around human environment and thus exposure of toxic contaminants in this animal considered to similar with those in humans. In addition, rats have unique physiology that match with humans (e.g., they have similar pathogens as humans have). Therefore, analysis of toxic contaminants in NR considered as indirect measure in humans. Considering those facts, in this study, we analyzed NR collected from urban area, rural area, waste dumping or land fill site and isolated remote island from Japan. Particularly several chlorinated and brominated organic contaminants such as PCDDs, PCDFs, PCBs, DDTs, HCHs, chlordane compounds, heptachlor, heptachlor epoxide, HCB, aldrin, dieldrin, endrin and PBDEs were analyzed in rat livers by isotope dilution technique using HRGC-HRMS. In addition, laboratory Wistar rats (WR) were used as control.

  18. Stabilization of Z-DNA by chemical bromination and its recognition by anti-Z-DNA antibodies

    International Nuclear Information System (INIS)

    Limited chemical bromination of poly[r(C-G)] (32% br8G, 26% br5C) results in partial modification of guanine C8 and cytosine C5, producing a mixture of A- and Z-RNA forms. The Z conformation in the brominated polynucleotide is stabilized at much lower ionic strength than in the unmodified polynucleotide. Raising the ionic strength to 6 M NaBr or NaClO4 results in a transition in Br-poly[r(C-G)] to a Z-RNA (Z/sub R/) conformation as judged by CD spectroscopy. 1H NMR data demonstrate a 1/1 mixture of A- and Z-RNAs in 110 mM NaBr buffer at 370C. Nuclear Overhauser effect (NOE) experiments permit complete assignments of GH8, CH6, CH5, GH1', AND CH1' resonances in both the A- and Z-forms. The NMR results indicate that unbrominated guanine residues undergo transition to the syn conformation (Z-form). Raman scattering data are consistent with a mixture of A- and Z-RNAs in 110 mM NaCl buffer at 37 0C. 31P NMR spectra show six to eight resonances spread over a 1.8 ppm range whose chemical shifts are also consistent with an equilibrium mixture of A- and Z-RNAs. Radioimmunoassay and nitrocellulose filter binding competition experiments were performed to determine the extent of recognition of Br-poly[r(C-G)] by anti-Z-DNA antibodies. Competition RIA experiments verify the presence of a Z-DNA-like determinant in left-handed Br-poly[r(C-G)] at physiological NaCl concentration. In summary, these spectroscopic and immunochemical studies demonstrate that under conditions of conformational stress (i.e., containing brominated nucleosides) left-handed Z-RNA is stable and is specifically recognized by proteins at physiological temperature and ionic strength

  19. Chicago's Sanitary and Ship Canal sediment: Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, brominated flame retardants, and organophosphate esters.

    Science.gov (United States)

    Peverly, Angela A; O'Sullivan, Colin; Liu, Liang-Ying; Venier, Marta; Martinez, Andres; Hornbuckle, Keri C; Hites, Ronald A

    2015-09-01

    The Chicago Sanitary and Ship Canal (CSSC) links the Great Lakes to the Mississippi River starting in downtown Chicago. In addition to storm water, the CSSC receives water from Chicago's wastewater treatment plants (WWTP). Such effluents are known to be sources of organic pollutants to water and sediment. Therefore in 2013, we collected 10 sediment samples from the CSSC and measured the concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), brominated flame retardants, and organophosphate esters (OPEs). Geometric mean concentrations of the summed concentrations of 16 PAHs ranged from 11,000 to 420,000 ng/g dw, with the highest concentrations located at each end of the canal. Total PCB concentrations had a geometric mean of 1,400 ± 500 ng/g dw. Brominated flame retardants were separated into two groups: polybrominated diphenyl ethers (PBDEs) and non-PBDEs. Concentrations of PBDEs and those of the non-PBDE flame retardants had a geometric average of 83 ± 19 and 7.0 ± 5.8 ng/g dw, respectively. The summed concentrations of 8 OPEs ranged from 470 to 2,800 ng/g dw, with the highest concentration detected at a site located downstream of the Stickney water reclamation plant. Using ANOVA results, some hypotheses on sources to the CSSC could be formulated: downtown Chicago is probably a source of PAHs, the Cal-Sag Channel may be a source of PCBs, and neither the WWTP nor the Cal-Sag Channel seem to be significant sources of brominated flame retardants or OPEs. PMID:25981316

  20. Formation of brominated phenolic contaminants from natural manganese oxides-catalyzed oxidation of phenol in the presence of Br(.).

    Science.gov (United States)

    Lin, Kunde; Song, Lianghui; Zhou, Shiyang; Chen, Da; Gan, Jay

    2016-07-01

    Brominated phenolic compounds (BPCs) are a class of persistent and potentially toxic compounds ubiquitously present in the aquatic environment. However, the origin of BPCs is not clearly understood. In this study, we investigated the formation of BPCs from natural manganese oxides (MnOx)-catalyzed oxidation of phenol in the presence of Br(-). Experiments at ambient temperature clearly demonstrated that BPCs were readily produced via the oxidation of phenol by MnOx in the presence of Br(-). In the reaction of MnOx sand with 0.213 μmol/L phenol and 0.34 mmol/L Br(-) for 10 min, more than 60% of phenol and 56% of Br(-) were consumed to form BPCs. The yield of BPCs increased with increasing concentrations of phenol and Br(-). Overall, a total of 14 BPCs including simple bromophenols (4-bromophenol, 2,4-dibromophenol, and 2,4,6-tribromophenol), hydroxylated polybrominated diphenyl ethers (OH-PBDEs), and hydroxylated polybrominated biphenyls (OH-PBBs) were identified. The production of BPCs increased with increasing concentrations of Br(-) or phenol. It was deduced that Br(-) was first oxidized to form active bromine, leading to the subsequent bromination of phenol to form bromophenols. The further oxidation of bromophenols by MnOx resulted in the formation of OH-PBDEs and OH-PBBs. In view of the ubiquity of phenol, Br(-), and MnOx in the environment, MnOx-mediated oxidation may play a role on the natural production of BPCs. PMID:27131033

  1. Synthesis and evaluation of a bromine-76-labeled PPAR{gamma} antagonist 2-bromo-5-nitro-N-phenylbenzamide

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hsiaoju [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Finck, Brian N. [Department of Internal Medicine, Division of Geriatrics and Nutritional Science, Washington University School of Medicine, St. Louis. MO 63110 (United States); Jones, Lynne A. [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Welch, Michael J. [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Mach, Robert H. [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110 (United States)]. E-mail: rhmach@mir.wustl.edu

    2006-10-15

    Peroxisome proliferator activated-receptor gamma (PPAR{gamma}) binds to peroxisome receptor response elements with its heterodimeric partner, retinoid X receptor, and regulates downstream gene expression. PPAR{gamma} transcriptionally modulates fat metabolism, and receptor agonists have been developed to treat type II diabetes. PPAR{gamma} is also overexpressed in some tumor cell lines and primary tumors, including breast and prostate tumors. Two PPAR{gamma} antagonists, 2-chloro-5-nitro-N-phenylbenzamide (GW9662) and 2-chloro-5-nitro-N-pyridin-4-yl-benzamide (T0070907), represent good lead compounds for radiotracer development. In the current study, four additional halogen substituted analogs were synthesized and evaluated in a whole cell screening assay for PPAR{gamma} binding activity. Two bromine-containing analogs having EC{sub 5} values <5 nM were chosen for bromine-76 radiolabeling. Bromine-76-labeled 2-bromo-5-nitro-N-phenyl-benzamide was selected for subsequent in vitro and in vivo studies due to its superior radiolabeling yield ({approx}70%) and the well-characterized pharmacological properties of its analog GW9662. An in vitro stability study showed that 40% of the compound remained intact in plasma and about 25% in whole blood after 30 min. Biodistribution studies in MDA-MB-435 human breast tumor-bearing nude mice were carried out at 5 min, 30 min, 2 h and 24 h post injection of the radiotracer. Although in vivo metabolite studies demonstrated rapid compound degradation, at least 10% of the parent compound was delivered to the tumor. We are currently exploring second generation analogs of these lead compounds for the development of radiolabeled antagonists of the PPAR{gamma} receptor.

  2. Microwave assisted extraction of iodine and bromine from edible seaweed for inductively coupled plasma-mass spectrometry determination.

    Science.gov (United States)

    Romarís-Hortas, Vanessa; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar

    2009-08-15

    The feasibility of microwave energy to assist the solubilisation of edible seaweed samples by tetramethylammonium hydroxide (TMAH) has been investigated to extract iodine and bromine. Inductively coupled plasma-mass spectrometry (ICP-MS) has been used as a multi-element detector. Variables affecting the microwave assisted extraction/solubilisation (temperature, TMAH volume, ramp time and hold time) were firstly screened by applying a fractional factorial design (2(5-1)+2), resolution V and 2 centre points. When extracting both halogens, results showed statistical significance (confidence interval of 95%) for TMAH volume and temperature, and also for the two order interaction between both variables. Therefore, these two variables were finally optimized by a 2(2)+star orthogonal central composite design with 5 centre points and 2 replicates, and optimum values of 200 degrees C and 10 mL for temperature and TMAH volume, respectively, were found. The extraction time (ramp and hold times) was found statistically non-significant, and values of 10 and 5 min were chosen for the ramp time and the hold time, respectively. This means a fast microwave heating cycle. Repeatability of the over-all procedure has been found to be 6% for both elements, while iodine and bromine concentrations of 24.6 and 19.9 ng g(-1), respectively, were established for the limit of detection. Accuracy of the method was assessed by analyzing the NIES-09 (Sargasso, Sargassum fulvellum) certified reference material (CRM) and the iodine and bromine concentrations found have been in good agreement with the indicative values for this CRM. Finally, the method was applied to several edible dried and canned seaweed samples. PMID:19576469

  3. In vitro and in ovo effects of four brominated flame retardants on toxicity and hepatic mRNA expression in chicken embryos.

    Science.gov (United States)

    Egloff, Caroline; Crump, Doug; Chiu, Suzanne; Manning, Gillian; McLaren, Kristina K; Cassone, Cristina G; Letcher, Robert J; Gauthier, Lewis T; Kennedy, Sean W

    2011-11-10

    Some currently used brominated flame retardants (BFRs), such as hexachlorocyclopentadienyl-dibromocyclooctane (HCDBCO), bis(2-ethylhexyl)tetrabromophthalate (BEHTBP), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenylethane (DBDPE), are persistent organic contaminants detected in various environmental matrices, including wild birds. Data on potential toxicological and molecular responses to exposure of these BFRs are lacking for avian species. A combined in vitro/in ovo approach was used to determine the concentration-dependent effects of these BFRs on overt toxicity and hepatic messenger RNA (mRNA) expression levels of 11 transcripts in (1) primary cultures of chicken embryonic hepatocytes (CEH; all four BFRs) and (2) chicken embryos (HCDBCO and BTBPE only). Neither hepatocyte viability nor embryonic pipping success were affected by the BFRs at any of the administered concentrations (CEH: 0.001-30 μM, egg injection: 0.1-10 μg/g nominal dose). In CEH, 10 μM HCDBCO induced cytochrome P450 2H1 (CYP2H1) and CYP3A37, while CYP1A4/5 were down-regulated at all tested concentrations. In contrast, only transthyretin was down-regulated by HCDBCO in embryonic liver. There was concordance between the BTBPE-induced transcriptional responses in vitro and in ovo for CYP1A4/5 (up-regulated) and type III iodothyronine 5'-deiodinase (DIO3; down-regulated). DBDPE induced CYP1A4/5 29- and 59-fold at 0.2 μM in CEH and increased DIO1. None of the gene targets were responsive to BEHTBP exposure in CEH. The multi-tiered in vitro/in ovo screening approach was effective for assessing toxicological and molecular biological effects of these BFRs in an avian species. PMID:21893176

  4. Neurobehavioral function and low-level exposure to brominated flame retardants in adolescents: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Kiciński Michał

    2012-11-01

    Full Text Available Abstract Background Animal and in vitro studies demonstrated a neurotoxic potential of brominated flame retardants, a group of chemicals used in many household and commercial products to prevent fire. Although the first reports of detrimental neurobehavioral effects in rodents appeared more than ten years ago, human data are sparse. Methods As a part of a biomonitoring program for environmental health surveillance in Flanders, Belgium, we assessed the neurobehavioral function with the Neurobehavioral Evaluation System (NES-3, and collected blood samples in a group of high school students. Cross-sectional data on 515 adolescents (13.6-17 years of age was available for the analysis. Multiple regression models accounting for potential confounders were used to investigate the associations between biomarkers of internal exposure to brominated flame retardants [serum levels of polybrominated diphenyl ether (PBDE congeners 47, 99, 100, 153, 209, hexabromocyclododecane (HBCD, and tetrabromobisphenol A (TBBPA] and cognitive performance. In addition, we investigated the association between brominated flame retardants and serum levels of FT3, FT4, and TSH. Results A two-fold increase of the sum of serum PBDE’s was associated with a decrease of the number of taps with the preferred-hand in the Finger Tapping test by 5.31 (95% CI: 0.56 to 10.05, p = 0.029. The effects of the individual PBDE congeners on the motor speed were consistent. Serum levels above the level of quantification were associated with an average decrease of FT3 level by 0.18 pg/mL (95% CI: 0.03 to 0.34, p = 0.020 for PBDE-99 and by 0.15 pg/mL (95% CI: 0.004 to 0.29, p = 0.045 for PBDE-100, compared with concentrations below the level of quantification. PBDE-47 level above the level of quantification was associated with an average increase of TSH levels by 10.1% (95% CI: 0.8% to 20.2%, p = 0.033, compared with concentrations below the level of quantification. We did not

  5. Highly brominated anthracenes as precursors for the convenient synthesis of 2,9,10-trisubstituted anthracene derivatives

    Directory of Open Access Journals (Sweden)

    2008-12-01

    Full Text Available When 9,10-dibromoanthracene was treated with bromine in CCl4 without a catalyst, 1,2,3,4,9,10-hexabromo-1,2,3,4-tetrahydroanthracene (3 was obtained in 95% yield in the absence of other stereoisomers or rearomatization products. We investigated the base-induced elimination reaction of hexabromide 3 under various conditions. Pyridine-induced elimination of hexabromide 3 afforded 2,9,10-tribromoanthracene (12 in 75% yield, and tribromide 12 was transformed to trimethoxy compound 13 and trinitrile 14 by copper-assisted nucleophilic substitution reactions.

  6. Experimental transition probabilities of intercombination transitions in Mg-like and Al-like ions of bromine

    International Nuclear Information System (INIS)

    Time-resolved extreme ultraviolet spectra of foil-excited 120-MeV Br ions have been recorded, using a spectrometer equipped with a position-sensitive detector. The spectra near λ=20--30 nm were measured at times after excitation of up to 6 ns. Prominent in the delayed spectra were the long-lived decays of the intercombination transitions in the Mg-like Br23+ and Al-like Br22+ ions. The present paper reports on lifetime measurements for intercombination transitions in highly charged bromine ions using such a position-sensitive detector

  7. Department of Atomic Energy [India]: Annual report 1978-79

    International Nuclear Information System (INIS)

    The research and development activities and achievements of the research organizations of the Department of Atomic Energy (DAE, India), progress of various DAE projects underway and performance of nuclear power plants and other public sector underking of DAE have been reported. The report covers the financial year 1978-79. Some of the major achievements during the year have been: (1) development of a portable local vacuum electron beam welding machine, (2) commissioning of the Variable Energy Cyclotron, Calcutta for obtaining an external beam of 30 MeV alphas, (4) locating minute leaks by tracer techniques on the 140 km. Koyali-Viramgam Oil pipeline and (5) investigation by tracer technique of geological fault at the Lakya dam site of the Kudremukh Iron Ore Project in Karnataka. The R and D work of the Bhabha Atomic Research Centre, Bombay; Reactor Research Centre, Kalpakkam; Tata Institute of Fundamental Research, Bombay; Saha Institute of Nuclear Physics, Calcutta, Tata Memorial Centre and Cancer Research Centre both at Bombay is summarised. (M.G.B.)

  8. Atmospheric neutrino oscillations in IceCube-79

    International Nuclear Information System (INIS)

    We present the results of an analysis of data collected by IceCube/DeepCore in 2010-2011 when operating in the 79 string configuration. This analysis results in the first significant detection of neutrino oscillations in a high-energy neutrino telescope. A low-energy muon neutrino sample (20-100 GeV) containing the oscillation signal was extracted from data collected by DeepCore. A high-energy muon neutrino sample (100 GeV-10 TeV) was extracted from IceCube data in order to constrain the systematic uncertainties. The non-oscillation hypothesis was rejected with more than 5σ. We fitted the oscillation parameters Δ m223 and sin22 θ23 to these data samples. In a 2-flavor formalism we find Δ m223 = (2.5±0.6). 10-3 eV2 and sin22 θ23 > 0.92 while maximum mixing is favored. These results are in good agreement with the world average values.

  9. Greenland ice core evidence of the 79 AD Vesuvius eruption

    Directory of Open Access Journals (Sweden)

    C. Barbante

    2012-11-01

    Full Text Available Volcanic tephra are indepenent age horizons and can synchronize strata of various paleoclimate records including ice and sediment cores. Before such paleoclimate records can be synchronized, it is essential to first confidently identify individual independent marker horizons. The Greenland Ice Core Project (GRIP ice core from Central Greenland is often used as a "golden spike" to synchronize Northern Hemisphere paleoclimte records. The Holocene section of the GRIP ice core is dated by multi-parameter annual layer counting, and contains peaks in acidity, SO42− and microparticle concentrations at a depth of 428.4 to 429.6 m, which have not previously been definitively ascribed to a volcanic eruption. Here, we identify tephra particles and determine that volcanic shards extracted from a depth of 429.2 m in the GRIP ice core are likely due to the 79 AD Vesuvius eruption. The chemical compositon of the tephra particles is consistent with the K-phonolitic composition of the Vesuvius juvinile ejecta and differs from the chemical composition of other major eruptions (≥VEI 4 between 50–100 AD.

  10. Implementation of thermal processes for feedstock recycling of bromine and antimony, with energy recovery, from plastics waste of electrical and electronic equipment (WEEE). Phase 1. Literature survey/status update, evaluation, and ranking of combustion, gasification, and pyrolysis based technologies

    Energy Technology Data Exchange (ETDEWEB)

    Boerrigter, H. [ECN Biomass, Petten (Netherlands)

    2000-11-01

    The bromine industry wants to process plastic Waste from Electrical and Electronic Equipment (WEEE), containing brominated flame retardants (BFRs), to recycle bromine, antimony, and other valuable metals, with energy recovery for sustainable production and closing the bromine loop at the End-of-Life. The motivation to perform the underlying study was that insufficient detailed information was available regarding the technical and economical feasibility of processing of WEEE with thermal processes (i.e. combustion, gasification, and pyrolysis-based technologies). The objective of the study was to make an inventory of available processes and evaluate them based on the following six criteria:Energy efficiency, Bromine and Antimony recovery, Emissions (legislation permits), General quality of residues/secondary products, Operational experience, and Profit expectations (ROI). 57 refs.

  11. CERN: Fixed target targets

    International Nuclear Information System (INIS)

    Full text: While the immediate priority of CERN's research programme is to exploit to the full the world's largest accelerator, the LEP electron-positron collider and its concomitant LEP200 energy upgrade (January, page 1), CERN is also mindful of its long tradition of diversified research. Away from LEP and preparations for the LHC proton-proton collider to be built above LEP in the same 27-kilometre tunnel, CERN is also preparing for a new generation of heavy ion experiments using a new source, providing heavier ions (April 1992, page 8), with first physics expected next year. CERN's smallest accelerator, the LEAR Low Energy Antiproton Ring continues to cover a wide range of research topics, and saw a record number of hours of operation in 1992. The new ISOLDE on-line isotope separator was inaugurated last year (July, page 5) and physics is already underway. The remaining effort concentrates around fixed target experiments at the SPS synchrotron, which formed the main thrust of CERN's research during the late 1970s. With the SPS and LEAR now approaching middle age, their research future was extensively studied last year. Broadly, a vigorous SPS programme looks assured until at least the end of 1995. Decisions for the longer term future of the West Experimental Area of the SPS will have to take into account the heavy demand for test beams from work towards experiments at big colliders, both at CERN and elsewhere. The North Experimental Area is the scene of larger experiments with longer lead times. Several more years of LEAR exploitation are already in the pipeline, but for the longer term, the ambitious Superlear project for a superconducting ring (January 1992, page 7) did not catch on. Neutrino physics has a long tradition at CERN, and this continues with the preparations for two major projects, the Chorus and Nomad experiments (November 1991, page 7), to start next year in the West Area. Delicate neutrino oscillation effects could become

  12. Spectroscopic UV/vis limb measurements from aboard the NASA Global Hawk: Implications for the photochemistry and budget of bromine in the tropical tropopause layer

    OpenAIRE

    Werner, Bodo

    2016-01-01

    The present thesis reports on the world's first measurements of the second most important ozone-depleting halogen bromine at the entrance to the stratosphere (14 - 18.5 km, theta = 330 - 400 K) over the East and Central Pacific in late winter 2013. The measurements were performed within the NASA-ATTREX project from aboard the unmanned aerial vehicle Global Hawk. For the interpretation of the remote-sensing DOAS measurements of O3, NO2 and BrO, use of complementary measurements of brominated s...

  13. Sputter target

    Science.gov (United States)

    Gates, Willard G.; Hale, Gerald J.

    1980-01-01

    The disclosure relates to an improved sputter target for use in the deposition of hard coatings. An exemplary target is given wherein titanium diboride is brazed to a tantalum backing plate using a gold-palladium-nickel braze alloy.

  14. Residues Met76 and Gln79 in HLA-G α1 domain involved in KIR2DL4 recognition

    Institute of Scientific and Technical Information of China (English)

    Wei Hua YAN; Li An FAN

    2005-01-01

    Human leukocyte antigen-G (HLA-G) has long been speculated as a beneficial factor for a successful pregnancy for its restricted expression on fetal-maternal extravillous cytotrophoblasts and its capability of modulating uterine natural killer cell (uNK) function such as cytotoxicity and cytokine production through NK cell receptors. HLA class I α1domain is an important killer cell Ig-like receptor (KIR) recognition site and the Met76 and Gln79 are unique to HLA-G in this region. NK cell receptor KIR2DL4 is a specific receptor for HLA-G, yet the recognition site on HLA-G remains unknown. In this study, retroviral transduction was applied to express the wild type HLA-G (HLA-wtG), mutant HLA-G (HLA-mG) on the chronic myelogenous leukemia cell line K562 cells and KIR2DL4 molecule on NK-92 cells,respectively. KIR2DL4-IgG Fc fusion protein was generated to determine the binding specificity between KIR2DL4and HLA-G. Our results showed that residue Met76, Gln79 mutated to Ala76,79 in the α1 domain of HLA-G protein could affect the binding affinity between KIR2DL4 and HLA-G, meanwhile, the KIR2DL4 transfected NK-92 cells (NK-92-2DL4) showed a considerably different cytolysis ability against the HLA-wtG and HLA-mG transfected K562 targets.Taken together, our data indicated that residue Met76 and Gln79 in HLA-G α1 domain plays a critical role in the recognition of KIR2DL4, which could be an explanation for the isoforms of HLA-G, all containing the α1 domain, with the potential to regulate NK functions.

  15. Physics landscape-fixed target energies

    International Nuclear Information System (INIS)

    An introductory review is presented of physics issues and opportunities at Fermilab fixed-target energies. Included are discussions of precision electroweak studies; deep inelastic lepton scattering; heavy quark production, spectroscopy, and decays; perturbative QCD; prompt photon production; massive lepton production; and spin dependence. 79 refs., 7 figs

  16. Set7/9, a methyltransferase, regulates the thermogenic program during brown adipocyte differentiation through the modulation of p53 acetylation.

    Science.gov (United States)

    Son, Min Jeong; Kim, Won Kon; Park, Anna; Oh, Kyoung-Jin; Kim, Jeong-Hoon; Han, Baek Soo; Kim, Il Chul; Chi, Seung-Wook; Park, Sung Goo; Lee, Sang Chul; Bae, Kwang-Hee

    2016-08-15

    Brown adipose tissue, which is mainly composed of brown adipocytes, plays a key role in the regulation of energy balance via dissipation of extra energy as heat, and consequently counteracts obesity and its associated-disorders. Therefore, brown adipocyte differentiation should be tightly controlled at the multiple regulation steps. Among these, the regulation at the level of post-translational modifications (PTMs) is largely unknown. Here, we investigated the changes in the expression level of the enzymes involved in protein lysine methylation during brown adipocyte differentiation by using quantitative real-time PCR (qPCR) array analysis. Several enzymes showing differential expression patterns were identified. In particular, the expression level of methyltransferase Set7/9 was dramatically repressed during brown adipocyte differentiation. Although there was no significant change in lipid accumulation, ectopic expression of Set7/9 led to enhanced expression of several key thermogenic genes, such as uncoupling protein-1 (UCP-1), Cidea, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), and PR domain containing 16 (PRDM16). In contrast, knockdown of endogenous Set7/9 led to significantly reduced expression of these thermogenic genes. Furthermore, suppressed mitochondrial DNA content and decreased oxygen consumption rate were also detected upon Set7/9 knockdown. We found that p53 acetylation was regulated by Set7/9-dependent interaction with Sirt1. Based on these results, we suggest that Set7/9 acts as a fine regulator of the thermogenic program during brown adipocyte differentiation by regulation of p53 acetylation. Thus, Set7/9 could be used as a valuable target for regulating thermogenic capacity and consequently to overcome obesity and its related metabolic diseases. PMID:27132805

  17. Thyroid cancer incidence among atomic bomb survivors, 1958-79

    International Nuclear Information System (INIS)

    One hundred and twelve cases of thyroid cancer diagnosed during the period 1958-79 among the extended Life Span Study cohort in Hiroshima and Nagasaki were studied. There was a statistically significant association between thyroid cancer incidence and exposure to atomic bomb radiation. The adjusted excess relative risk (ERR) per gray was 1.1 (95% confidence interval=0.3-2.5) and the adjusted absolute risk per 104 PYGy was 0.59 (95% confidence interval=0.2-1.7). Based on a comparison of the deviances obtained from relative and absolute risk models, a simple linear relative risk model appeared to fit the data better than an absolute risk model; however, it would not be appropriate to conclude that the data conform strictly to a relative risk pattern. The incidence of thyroid cancer among the members of the Adult Health Study (AHS) population, who have received biennial medical examinations at the Atomic Bomb Casualty Commission and its successor the Radiation Effects Research Foundation, since 1958, was 70% higher than that among the rest of the extended LSS cohort after adjustments for city, sex, log age, calendar year, and Dosimetry System 1986 dose. There was no significant difference between the slope of the dose-response curve for AHS and non-AHS participants, although the estimated ERRs at 1 Gy for the AHS and non-AHS population were 1.6 and 0.3, respectively. The elevated risk appeared to be confined to women, and there was an increasing risk with decreasing attained age and age at exposure. (J.P.N.)

  18. Direct spectral analysis and determination of high content of carcinogenic bromine in bread using UV pulsed laser induced breakdown spectroscopy.

    Science.gov (United States)

    Mehder, A O; Gondal, Mohammed A; Dastageer, Mohamed A; Habibullah, Yusuf B; Iqbal, Mohammed A; Oloore, Luqman E; Gondal, Bilal

    2016-06-01

    Laser induced breakdown spectroscopy (LIBS) was applied for the detection of carcinogenic elements like bromine in four representative brands of loaf bread samples and the measured bromine concentrations were 352, 157, 451, and 311 ppm, using Br I (827.2 nm) atomic transition line as the finger print atomic transition. Our LIBS system is equipped with a pulsed laser of wavelength 266 nm with energy 25 mJ pulse(-1), 8 ns pulse duration, 20 Hz repetition rate, and a gated ICCD camera. The LIBS system was calibrated with the standards of known concentrations in the sample (bread) matrix and such plot is linear in 20-500 ppm range. The capability of our system in terms of limit of detection and relative accuracy with respect to the standard inductively coupled plasma mass spectrometry (ICPMS) technique was evaluated and these values were 5.09 ppm and 0.01-0.05, respectively, which ensures the applicability of our system for Br trace level detection, and LIBS results are in excellent agreement with that of ICPMS results. PMID:26950676

  19. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains: field measurements and model calculations.

    Science.gov (United States)

    Veltman, Karin; Hendriks, Jan; Huijbregts, Mark; Leonards, Pim; van den Heuvel-Greve, Martine; Vethaak, Dick

    2005-10-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and marine mammals. Accumulation of polychlorinated biphenyls is predicted well by OMEGA for herbi-detritivores and primary and secondary carnivorous fish. Ratios are similar to those found for fresh water species. Accumulation ratios for fish-eating birds and mammals are overestimated by the model, which is attributed partly to biotransformation of meta-para unsubstituted congeners. Additionally, birds may feed in other less polluted areas. For brominated diphenylethers (BDE) accumulation patterns are highly species and congener specific. Accumulation depends on both K(ow) and metabolization capacities. BDE47 is the predominant congener in lower trophic levels. For marine birds and mammals accumulation ratios of BDE99 and 100 are similar to or higher than ratios of persistent PCBs. PMID:15893330

  20. Bromination of graphene: a new route to making high performance transparent conducting electrodes with low optical losses

    KAUST Repository

    Mansour, Ahmed

    2015-09-03

    The high optical transmittance, electrical conductivity, flexibility and chemical stability of graphene have triggered great interest in its application as a transparent conducting electrode material and as a potential replacement for indium doped tin oxide. However, currently available large scale production methods such as chemical vapor deposition produce polycrystalline graphene, and require additional transfer process which further introduces defects and impurities resulting in a significant increase in its sheet resistance. Doping of graphene with foreign atoms has been a popular route for reducing its sheet resistance which typically comes at a significant loss in optical transmission. Herein, we report the successful bromine doping of graphene resulting in air-stable transparent conducting electrodes with up to 80% reduction of sheet resistance reaching ~180 Ω/ at the cost of 2-3% loss of optical transmission in case of few layer graphene and 0.8% in case of single layer graphene. The remarkably low tradeoff in optical transparency leads to the highest enhancements in figure of merit reported thus far. Furthermore, our results show a controlled increase in the workfunction up to 0.3 eV with the bromine content. These results should help pave the way for further development of graphene as potentially a highly transparent substitute to other transparent conducting electrodes in optoelectronic devices.

  1. Cobalt catalyzed peroxymonosulfate oxidation of tetrabromobisphenol A: Kinetics, reaction pathways, and formation of brominated by-products.

    Science.gov (United States)

    Ji, Yuefei; Kong, Deyang; Lu, Junhe; Jin, Hao; Kang, Fuxing; Yin, Xiaoming; Zhou, Quansuo

    2016-08-01

    Degradation of tetrabromobisphenol A (TBBPA), a flame retardant widely spread in the environment, in Co(II) catalyzed peroxymonosulfate (PMS) oxidation process was systematically explored. The second-order-rate constant for reaction of sulfate radical (SO4(-)) with TBBPA was determined to be 5.27×10(10)M(-1)s(-1). Apparently, degradation of TBBPA showed first-order kinetics to the concentrations of both Co(II) and PMS. The presence of humic acid (HA) and bicarbonate inhibited TBBPA degradation, most likely due to their competition for SO4(-). Degradation of TBBPA was initiated by an electron abstraction from one of the phenolic rings. Detailed transformation pathways were proposed, including β-scission of isopropyl bridge, phenolic ring oxidation, debromination and coupling reactions. Further oxidative degradation of intermediates in Co(II)/PMS process yielded brominated disinfection by-products (Br-DBPs) such as bromoform and brominated acetic acids. Evolution profile of Br-DBPs showed an initially increasing and then decreasing pattern with maximum concentrations occurring around 6-10h. The presence of HA enhanced the formation of Br-DBPs significantly. These findings reveal potentially important, but previously unrecognized, formation of Br-DBPs during sulfate radical-based oxidation of bromide-containing organic compounds that may pose toxicological risks to human health. PMID:27107323

  2. Association between exposures to brominated trihalomethanes, hepatic injury and type II diabetes mellitus.

    Science.gov (United States)

    Makris, Konstantinos C; Andrianou, Xanthi D; Charisiadis, Pantelis; Burch, James B; Seth, Ratanesh K; Ioannou, Androniki; Picolos, Michael; Christophi, Costas A; Chatterjee, Saurabh

    2016-01-01

    Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver disorder in the Western world, commonly diagnosed in the majority of obese patients with type 2 diabetes mellitus (T2DM). Metabolic disrupting chemicals with short half-lives, such as those of halogenated structure (trihalomethanes, THM) have been linked with hepatic insulin resistance phenomena in animal studies. However, human studies evaluating the role of THM exposure on liver pathogenesis and T2DM disease process are scarce. The objectives of this study were to: i) determine the association of urinary brominated THM (BrTHM) levels and T2DM disease status, and ii) investigate the association between urinary BrTHM levels and serum alanine aminotransferase (ALT) concentrations, often used as surrogate markers of NAFLD. A pilot case-control study was conducted in Nicosia, Cyprus (n=95). Cases were physician-diagnosed T2DM patients and controls were healthy individuals. Liver enzymes, leptin and TNF-α were measured in sera, while urinary THM levels were measured using tandem mass spectrometry. Diabetics had higher levels of serum leptin, body mass index and ALT than the controls. Among all study participants those with serum ALT levels above the median (17IU/L) had higher mean tribromomethane (TBM) concentrations compared to those with serum ALT below 17IU/L. A significant increase in the odds of having above the median serum ALT levels [OR 6.38, 95% CI: 1.11, 42.84 (p=0.044)] was observed for each unit increase in creatinine-unadjusted urinary TBM levels, along with BMI and past smoking, after adjusting for possible confounders, such as urinary creatinine, age, sex, and leptin; no other THM compound showed a significant association with serum ALT. Logistic regression models for T2DM using the urinary BrTHM as exposure variables did not reach the predetermined level of significance. The interplay between exposures to BrTHM and the initiation of key pathophysiological events relating to

  3. Hydrogen generation using a calcium-bromine thermochemical water-splitting cycle

    International Nuclear Information System (INIS)

    The Secure Transportable Autonomous (STAR-H2) project is part of the US Department of Energy's (DOE's) Nuclear Energy Research Initiative (NERI) to develop Generation IV (Gen IV) nuclear reactors that will supply high-temperature (over 1100 K; 800 deg C) heat. The goal of NERI is to develop an economical, proliferation-resistant, sustainable, nuclear-based energy supply system based on a modular-sized fast reactor that is passively safe and cooled with heavy liquid metal. STAR-H2 consists of the following: - A 400-MWThermal reactor with Pb as the primary coolant; - Exchange of primary Pb coolant for a salt heat transfer pipe; - Exchange of salt for steam; - A combined thermochemical water-splitting cycle to generate hydrogen; - CO2 Brayton cycle to generate electricity (η = 47%), and - An optional capability to produce potable water from brackish or salt water. Here we review the thermodynamic basis for a three-stage calcium-bromine (Ca-Br) water-splitting cycle. The research builds upon pioneering work on the four-stage University of Tokyo Cycle no.3 (UT--3) process, but employs a plasma-chemical stage for the recovery of HBr as H2 and Br2 as a substitute for the final two stages of UT-3. A detailed process design, developed by using the ASPEN model, suggests that the practical efficiency is 39-45% for the STAR-H2 Ca-Br cycle. For each tonne of H2 produced hourly (1 000 kg/h), the demand for electricity for the plasma-chemical stage (13.5 MWe) is much lower than the demand (28.5 MWe) for a steam-electrolysis system. At current power grid heat-to-electricity efficiencies (η = 33%), there is a clear benefit for using the STAR-H2 Ca-Br cycle. Anticipating Brayton cycle performance (η = 47%), H2 production will demand a total power of 74 MWThermal per ton of H2 from the Gen IV reactor. It is important to recognize that there are capital and operating cost tradeoffs that will depend on the market value of low-carbon electricity in the future. Steam-electrolysis is a

  4. Revision and extension to the analysis of the third spectrum of bromine: Br III

    International Nuclear Information System (INIS)

    The spectrum of doubly ionized bromine (Br III) has been investigated in the vacuum ultraviolet wavelength region. Br2+ is an As-like ion with ground configuration of 4s24p3, thus a 3-electron system possessing a complex structure. The theoretical prediction was made using Cowan's quasi-relativistic Hartree–Fock code with superposition of configurations involving the 4s4p4, 4s24p2 (4d+5d+6d+5s+6s+7s), 4s4p3 (5p+4f), 4p4(4d+5s), 4s24p5s5p, 4s4p2 (4d2+5s2), 4s4p24f2 configurations for the even parity matrix and the 4s24p3, 4s24p2 (5p+6p+4f+5f) configurations for the odd parity matrix. Several previously reported levels of Br III have been revised, and new configurations have been added to the analysis. The spectrum used for this work was recorded on a 3-m normal incidence spectrograph in the wavelength region of 400–1326 Å using a triggered vacuum spark source. One hundred and two energy levels belonging to the 4s24p3, 4s4p4, 4s24p2 (4d+5d+6d+5s+6s +7s) configurations have been established, eighty-six being new. Two hundred and seventy-eight lines have been identified in this spectrum. The accuracy of our wavelength measurements for sharp and unblended lines is ±0.006 Å. The ionization potential of Br III was found to be 281,250±100 cm−1 (34.870±0.012 eV). - Highlights: • The spectrum of Br was recorded on a 3-m grating spectrograph with a triggered spark source. • Most of the known energy levels have been revised and further new configurations have been added. • Superposition-of-configurations calculations with relativistic corrections were made for theoretical predictions. • Radiative weighted oscillator strength (gf) & radiative transition probabilities (gA) were calculated. • Ionization Potential of Br III was determined experimentally

  5. Measurement-based modelling of bromine-induced oxidation of mercury above the Dead Sea

    Directory of Open Access Journals (Sweden)

    E. Tas

    2012-03-01

    Full Text Available Atmospheric mercury depletion events (AMDEs outside the polar region – driven by high levels of gaseous Br and BrO (i.e., BrOx – were observed recently in the warm Dead Sea boundary layer. The efficient oxidation of gaseous elemental mercury (GEM under temperate conditions by BrOx was unexpected considering that the thermal back dissociation reaction of HgBr is about 2.5 orders of magnitude higher under Dead Sea temperatures compared to polar temperatures, and hence was expected to significantly slow down GEM oxidation under warm temperatures. The goal of this modelling study was to improve understanding of the interaction of reactive bromine and mercury during Dead Sea AMDEs using numerical simulations based on a comprehensive measurement campaign in summer 2009.

    Our analysis is focused on daytime AMDE when chemical processes dominate concentration changes. Best agreements between simulations and observations were achieved using rate constants for kHg+Br and kHg+BrO of 2.7 × 10−13 cm3 molecule−1 s−1 and 1.5 × 10−13 cm3 molecule−1 s−1, respectively. Our model also predicted that a rate constant kHg+BrO of 5.0 × 10−14 cm3 molecule−1 s−1 may be considered as a minimum, which is higher than most reported values. These rate constants suggest that BrO could be a more efficient oxidant than Br in the troposphere as long as [Br]/[BrO] ratios are smaller than ~0.2 to 0.5. Under Dead Sea conditions, these kinetics demonstrate a high efficiency and central role of BrOx for AMDEs, with relative contributions to GEM depletion of more than ~90%. Unexpectedly, BrO was found to be the dominant oxidant with relative contributions above 80%. The strong contribution of BrO could explain why the efficiency of GEM

  6. Target capture and target ghosts

    Science.gov (United States)

    Auerbach, Steven P.

    1996-05-01

    Optimal detection methods for small targets rely on whitened matched filters, which convolve the measured data with the signal model, and whiten the result with the noise covariance. In real-world implementations of such filters, the noise covariance must be estimated from the data, and the resulting covariance estimate may be corrupted by presence of the target. The resulting loss in SNR is called 'target capture'. Target capture is often thought to be a problem only for bright targets. This presentation shows that target capture also arises for dim targets, leading to an SNR loss which is independent of target strength and depends on the averaging method used to estimate the noise covariance. This loss is due to a 'coherent beat' between the true noise and that portion of the estimated noise covariance due to the target. This beat leads to 'ghost targets', which diminish the target SNR by producing a negative target ghost at the target's position. A quantitative estimate of this effect will be given, and shown to agree with numerical results. The effect of averaging on SNR is also discussed for data scenes with synthetic injected targets, in cases where the noise covariance is estimated using 'no target' data. For these cases, it is shown that the so-called 'optimal' filter, which uses the true noise covariance, is actually worse than a 'sub-optimal' filter which estimates the noise from scene. This apparent contradiction is resolved by showing that the optimal filter is best if the same filter is used for many scenes, but is outperformed by a filter adapted to a specific scene.

  7. Effectiveness of the KiVa Antibullying Program: Grades 1-3 and 7-9

    Science.gov (United States)

    Karna, Antti; Voeten, Marinus; Little, Todd D.; Alanen, Erkki; Poskiparta, Elisa; Salmivalli, Christina

    2013-01-01

    This study investigated the effectiveness of the KiVa Antibullying Program in two samples of students, one from Grades 1-3 (7-9 years old, N = 6,927) and the other from Grades 7-9 (13-15 years old, N = 16, 503). The Grades 1-3 students were located in 74 schools and Grades 7-9 students in 73 schools that were randomly assigned to intervention and…

  8. Landscape response to the Mw7.9 Gorkha earthquake

    Science.gov (United States)

    Andermann, Christoff; Turowski, Jens; Behling, Robert; Cook, Kristen; Hovius, Niels; Marc, Odin; Roessner, Sigrid; Sens-Schoenfelder, Christoph; Emberson, Robert; Burtin, Arnaud; Dietze, Michael; Adhikari, Basanta; Parajuli, Binod

    2016-04-01

    Strong earthquakes cause transient perturbations of the near Earth's surface system. These include the widespread landsliding and subsequent mass movement and the loading of rivers with sediments. In addition, rock mass is shattered during the event, forming cracks that affect rock strength and hydrological conductivity. Often overlooked in the immediate aftermath of an earthquake, these perturbations can represent a major part of the overall disaster with an impact that can last for years before restoring to background conditions. Thus, the relaxation phase is part of the seismically induced change by an earthquake and need to be monitored in order to understand the full impact of earthquakes on the Earth system. Here, we present first results from the rapid respond earth surface processes monitoring program put in place by several European groups after the Mw7.9 Gorkha earthquake. To monitor the transient effects of the earthquake on the Earth surface system, we have installed a comprehensive network of 13 river sampling locations for daily water and sediment sampling, covering all major rivers draining the earthquake-affected areas immediately after the event. Nested within this regional network, we have installed an array of 16 seismometers and geophones and 6 weather stations in the upper Bhotekoshi catchment, covering an area of ~50 km2. The field measurements are accompanied by repeated mapping of landslide activities and volumes over subsequent seasons using high resolution optical (RapidEye) and radar imagery (TanDEM TerraSAR-X). The combination of all of these data will help when interpreting our field observation in the regional context of catastrophic failure of hillslopes and their link with sediment transport in the rivers. First river gauging observation show a pronounced increase in river discharge in the order of >20% for the respective pre-monsoon season. We interpreted this as a direct impact of the shaking on the valley-ridge scale sub

  9. Comparison of direct injection nebulizer and desolvating microconcentric nebulizer for analysis of chlorine-, bromine- and iodine-containing compounds by reversed phase HPLC with ICP-MS detection

    DEFF Research Database (Denmark)

    Jensen, B.P.; Gammelgaard, Bente; Hansen, S.H.;

    2003-01-01

    With the purpose of finding ways to combine micro-bore reversed phase HPLC with ICP-MS detection for analysis of drug substances containing chlorine, bromine and iodine, the suitability of a direct injection nebulizer and an Aridus desolvating microconcentric nebulizer was compared. Using the...

  10. Synthesis, characterization, crystal structure, catalytic activity in oxidative bromination, and thermal study of a new oxidovanadium Schiff base complex containing O, N-bidentate Schiff base ligand

    Czech Academy of Sciences Publication Activity Database

    Grivani, G.; Tahmasebi, V.; Khalaji, A.D.; Eigner, Václav; Dušek, Michal

    2014-01-01

    Roč. 67, č. 22 (2014), s. 3664-3677. ISSN 0095-8972 Institutional support: RVO:68378271 Keywords : oxidovanadium(IV) * Schiff base * single crystal * oxidative bromination Subject RIV: CA - Inorganic Chemistry Impact factor: 2.012, year: 2014

  11. Brominated flame retardant levels in human milk and serum from MAMA study participants: Correlations over time, matrix, and with questionnaire results

    Science.gov (United States)

    Brominated flame retardants (BFRs) are synthetic, lipophilic, and bioaccumulative compounds used to prevent the combustion of a variety of items including electronics and furniture. There are 75 classes of BFRs, two of which are the polybrominated biphenyls (PBB) and the polybrom...

  12. Resistivity features in intercalated graphite compounds with bromine and iodine chloride in the region of structural phase transitions in the layer of intercalate

    International Nuclear Information System (INIS)

    In the paper anomalous changes of resistivity in graphite intercalated compounds with iodine chloride and bromine are investigated in the phase transition temperature interval. It is shown that these anomalies are caused by the change of carriers mobility in the phase transitional interval as well as by the origin of ''mobile ions liquids''

  13. Formation of brominated disinfection byproducts from natural organic matter isolates and model compounds in a sulfate radical-based oxidation process

    KAUST Repository

    Wang, Yuru

    2014-12-16

    A sulfate radical-based advanced oxidation process (SR-AOP) has received increasing application interest for the removal of water/wastewater contaminants. However, limited knowledge is available on its side effects. This study investigated the side effects in terms of the production of total organic bromine (TOBr) and brominated disinfection byproducts (Br-DBPs) in the presence of bromide ion and organic matter in water. Sulfate radical was generated by heterogeneous catalytic activation of peroxymonosulfate. Isolated natural organic matter (NOM) fractions as well as low molecular weight (LMW) compounds were used as model organic matter. Considerable amounts of TOBr were produced by SR-AOP, where bromoform (TBM) and dibromoacetic acid (DBAA) were identified as dominant Br-DBPs. In general, SR-AOP favored the formation of DBAA, which is quite distinct from bromination with HOBr/OBr- (more TBM production). SR-AOP experimental results indicate that bromine incorporation is distributed among both hydrophobic and hydrophilic NOM fractions. Studies on model precursors reveal that LMW acids are reactive TBM precursors (citric acid > succinic acid > pyruvic acid > maleic acid). High DBAA formation from citric acid, aspartic acid, and asparagine was observed; meanwhile aspartic acid and asparagine were the major precursors of dibromoacetonitrile and dibromoacetamide, respectively.

  14. Treatment with connexin 46 siRNA suppresses the growth of human Y79 retinoblastoma cell xenografts in vivo.

    Science.gov (United States)

    Burr, Diana B; Molina, Samuel A; Banerjee, Debarshi; Low, Derek M; Takemoto, Dolores J

    2011-04-01

    Tumors with a hypoxic component, including human Y79 retinoblastoma cells, express a specific gap junction protein, Connexin 46 (Cx46), which is usually only found in naturally hypoxic tissues such as the differentiated lens. The aim of this study was to investigate if Cx46 downregulation would suppress Y79 tumor formation in vivo. Five-week old nude mice were subcutaneously implanted with human Y79 retinoblastoma cells and treated with intratumor siRNA injections of 30 μg Cx46 siRNA (n = 6), 30 μg non-silencing siRNA (n = 6), or no siRNA treatment (n = 6) every 2 days for a maximum of 10 treatments. Tumor volume (TV) was calculated from the recorded caliper measurements of length and width. Excised tumors were measured and weighed. Western blot analyses were performed to evaluate Cx46 and Cx43 expression in tumors which received Cx46 siRNA, non-silencing siRNA, or no siRNA treatment. Tumor histopathology was used to assess tumor features. Cx46 siRNA treated Y79 tumors had a reduced TV (287 mm(3) ± 77 mm(3)) when compared to the tumors of mice receiving the negative control siRNA (894 mm(3) ± 218 mm(3); P ≤ 0.03) or no siRNA (1068 mm(3) ± 192 mm(3); P ≤ 0.002). A 6-fold knockdown of Cx46 and a 3-fold rise in Cx43 protein expression was observed from western blots of tumors treated with Cx46 siRNA compared to mice treated with non-silencing siRNA. Knockdown of Cx46 with siRNA had an antitumor effect on human Y79 retinoblastoma tumors in the nude mouse model. The results suggest that anti-Cx46 therapy may be a potential target in the future treatment of retinoblastoma. PMID:21320488

  15. Deriving an atmospheric budget of total organic bromine using airborne in situ measurements from the western Pacific area during SHIVA

    Science.gov (United States)

    Sala, S.; Bönisch, H.; Keber, T.; Oram, D. E.; Mills, G.; Engel, A.

    2014-07-01

    During the recent SHIVA (Stratospheric Ozone: Halogen Impacts in a Varying Atmosphere) project an extensive data set of all halogen species relevant for the atmospheric budget of total organic bromine was collected in the western Pacific region using the Falcon aircraft operated by the German Aerospace agency DLR (Deutsches Zentrum für Luft- und Raumfahrt) covering a vertical range from the planetary boundary layer up to the ceiling altitude of the aircraft of 13 km. In total, more than 700 measurements were performed with the newly developed fully automated in situ instrument GHOST-MS (Gas chromatograph for the Observation of Tracers - coupled with a Mass Spectrometer) by the Goethe University of Frankfurt (GUF) and with the onboard whole-air sampler WASP with subsequent ground-based state-of-the-art GC / MS analysis by the University of East Anglia (UEA). Both instruments yield good agreement for all major (CHBr3 and CH2Br2) and minor (CH2BrCl, CHBrCl2 and CHBr2Cl) VSLS (very short-lived substances), at least at the level of their 2σ measurement uncertainties. In contrast to the suggestion that the western Pacific could be a region of strongly increased atmospheric VSLS abundance (Pyle et al., 2011), we found only in the upper troposphere a slightly enhanced amount of total organic bromine from VSLS relative to the levels reported in Montzka and Reimann et al. (2011) for other tropical regions. From the SHIVA observations in the upper troposphere, a budget for total organic bromine, including four halons (H-1301, H-1211, H-1202, H-2402), CH3Br and the VSLS, is derived for the level of zero radiative heating (LZRH), the input region for the tropical tropopause layer (TTL) and thus also for the stratosphere. With the exception of the two minor VSLS CHBrCl2 and CHBr2Cl, excellent agreement with the values reported in Montzka and Reimann et al. (2011) is found, while being slightly higher than previous studies from our group based on balloon-borne measurements.

  16. 海水提溴技术的发展与研究现状%Research and development status of bromine extracting technique from sea water

    Institute of Scientific and Technical Information of China (English)

    林源; 王浩宇; 周亚蓉; 叶俊伟; 宁桂玲

    2012-01-01

    Bromine is one of the important chemical materials.lt has been widely used in the fields of flame retardants,oil exploration,fungicides,pesticides, photographic materials,and pharmaceutical etc..Bromine's preparation technology and potential value are highly attached by domestic and foreign scholars.The status of bromine production and extraction methods from sea water,including air stripping method,steam distillation method,ion exchange adsorption method,and membrane separation method at home and abroad were briefly introduced.The advantages and disadvantages of those methods were compared.Meanwhile, the preparation method of ultrapure bromine was briefly described.Finally, the future development direction of extracting bromine from sea water was suggested.%溴素是重要的化工原料之一,在阻燃剂、石油开采、杀菌剂、农药、感光材料及医药等领域广泛应用,其制备技术和应用价值受到国内外学者的高度重视.综述了国内外溴素生产现状和海水提溴的方法,介绍了空气吹出法、水蒸气蒸馏法、离子交换吸附法和膜分离法提溴技术的研究现状,分析了各种方法的优缺点.简述了超纯溴的制备方法.提出了海水提溴的未来发展方向.

  17. Maternal transfer of emerging brominated and chlorinated flame retardants in European eels

    Energy Technology Data Exchange (ETDEWEB)

    Sühring, Roxana, E-mail: roxana.suehring@hzg.de [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg (Germany); Freese, Marko [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Schneider, Mandy [Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg (Germany); Schubert, Sophia; Pohlmann, Jan-Dag [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Alaee, Mehran [Water Science and Technology Directorate, Environment Canada, Burlington, Ontario, L7R4A6 Canada (Canada); Wolschke, Hendrik [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg (Germany); Hanel, Reinhold [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Ebinghaus, Ralf [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Marohn, Lasse [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany)

    2015-10-15

    The European eel (Anguilla anguilla) is regarded as a critically endangered species. Scientists are in agreement that the “quality of spawners” is a vital factor for the survival of the species. This quality can be impaired by parasites, disease and pollution. Especially endocrine disrupting organic chemicals pose a potential threat to reproduction and development of offspring. To our knowledge, the findings in this publication for the first time describe maternal transfer of contaminants in eels. We analysed the concentrations of in total 53 polybrominated diphenyl ethers (PBDEs) and their halogenated substitutes in muscle, gonads and eggs of artificially matured European eels and in muscle and gonads of untreated European eels that were used for comparison. We found evidence that persistent organic pollutants such as PBDEs, as well as their brominated and chlorinated substitutes are redistributed from muscle tissue to gonads and eggs. Concentrations ranged from 0.001 ng g{sup −1} ww for sum Dechlorane metabolites (DPMA, aCL{sub 10}DP, aCl{sub 11}DP) to 2.1 ng g{sup −1} ww for TBA in eggs, 0.001 ng g{sup −1} ww for Dechlorane metabolites to 9.4 ng g{sup −1} ww for TBA in gonads and 0.002 ng g{sup −1} ww for Dechlorane metabolites to 54 ng g{sup −1} ww for TBA in muscle tissue. Average egg muscle ratios (EMRs) for compounds detectable in artificially matured eels from both Schlei Fjord and Ems River ranged from 0.01 for Dechlorane 602 (DDC-DBF) to 10.4 for PBEB. Strong correlations were found between flame retardant concentrations and lipid content in the analysed tissue types, as well as transfer rates and octanol–water partitioning coefficient, indicating that these parameters were the driving factors for the observed maternal transfer. Furthermore, indications were found, that TBP-DBPE, TBP-AE, BATE and TBA have a significant uptake from the surrounding water, rather than just food and might additionally be formed by metabolism or

  18. Maternal transfer of emerging brominated and chlorinated flame retardants in European eels

    International Nuclear Information System (INIS)

    The European eel (Anguilla anguilla) is regarded as a critically endangered species. Scientists are in agreement that the “quality of spawners” is a vital factor for the survival of the species. This quality can be impaired by parasites, disease and pollution. Especially endocrine disrupting organic chemicals pose a potential threat to reproduction and development of offspring. To our knowledge, the findings in this publication for the first time describe maternal transfer of contaminants in eels. We analysed the concentrations of in total 53 polybrominated diphenyl ethers (PBDEs) and their halogenated substitutes in muscle, gonads and eggs of artificially matured European eels and in muscle and gonads of untreated European eels that were used for comparison. We found evidence that persistent organic pollutants such as PBDEs, as well as their brominated and chlorinated substitutes are redistributed from muscle tissue to gonads and eggs. Concentrations ranged from 0.001 ng g−1 ww for sum Dechlorane metabolites (DPMA, aCL10DP, aCl11DP) to 2.1 ng g−1 ww for TBA in eggs, 0.001 ng g−1 ww for Dechlorane metabolites to 9.4 ng g−1 ww for TBA in gonads and 0.002 ng g−1 ww for Dechlorane metabolites to 54 ng g−1 ww for TBA in muscle tissue. Average egg muscle ratios (EMRs) for compounds detectable in artificially matured eels from both Schlei Fjord and Ems River ranged from 0.01 for Dechlorane 602 (DDC-DBF) to 10.4 for PBEB. Strong correlations were found between flame retardant concentrations and lipid content in the analysed tissue types, as well as transfer rates and octanol–water partitioning coefficient, indicating that these parameters were the driving factors for the observed maternal transfer. Furthermore, indications were found, that TBP-DBPE, TBP-AE, BATE and TBA have a significant uptake from the surrounding water, rather than just food and might additionally be formed by metabolism or biotransformation processes. Dechloranes seem to be of

  19. SPS Outstanding Student Award for Undergraduate Research Talk: Lifetime Measurements and Deformation in 79Sr

    Science.gov (United States)

    Ryu, Yun Kyoung; Kaye, Robert; Arora, S. R.; Tabor, S. L.; Doring, J.; Sun, Y.; Baldwin, T. D.; Campbell, D. B.; Chandler, C.; Cooper, M. W.; Gerbick, S. M.; Wiedeking, M.; Hoffman, C. R.; Pavan, J.; Grubor-Urosevic, O.; Riley, L. A.

    2008-04-01

    High-spin states in ^79Sr were produced following the ^54Fe(^28Si, 2pn) fusion-evaporation reaction using a beam kinetic energy of 90 MeV at the Florida State University (FSU) Tandem-Linac particle accelerator facility, and the resulting de-exciting γ rays were detected with the FSU array of 10 Compton-suppressed high-purity Ge detectors comprised of three Clover detectors and seven single-crystal detectors. The synthesized nuclei were stopped completely in the target, resulting in Doppler-shifted γ-ray line shapes that could be analyzed using the Doppler-shift attenuation method. The experimental line shapes were acquired at detection angles of 35 and 145 , and the resulting Doppler-shifted peaks were analyzed to extract the lifetime of their parent states. In all, 23 lifetimes were measured in three separate band structures using this method, and then used to infer transition quadrupole moments (Qt) and quadrupole deformations (β2) using the rotational model. The resulting Qt values indicated a high degree of collectivity and deformation in all three observed sequences of excited states (bands) with only a modest decline in collectivity with increasing angular momentum. The results show good qualitative agreement with the predictions of both cranked Woods-Saxon (CWS) and projected shell model (PSM) calculations. In addition, the pattern of excited energy states and their de-exciting gamma-ray transitions (level scheme) was re-examined and compared to the most recent study of ^79Sr using γ-γ coincidence measurements, intensity measurements, and directional correlation of oriented nuclei (DCO) ratios in addition to the lifetime measurements. Overall, the level scheme was verified, with the exception of the re-arrangement of one transition. The band based on the intrinsic d5/2 single-particle orbital from the shell model, was found to have the largest average deformation (β2,ave = 0.41) among the three observed bands, in agreement with the CWS and PSM

  20. Controlled indole-3-acetaldoxime production through ethanol-induced expression of CYP79B2

    DEFF Research Database (Denmark)

    Mikkelsen, M.D.; Fuller, V.L.; Hansen, Bjarne Gram;

    2009-01-01

    Indole-3-acetaldoxime (IAOx) is a key branching point between primary and secondary metabolism. IAOx serves as an intermediate in the biosynthesis of indole glucosinolates (I-GLSs), camalexin and the plant hormone indole-3-acetic acid (IAA). The cytochrome P450s CYP79B2 and CYP79B3 catalyze the...

  1. 19 CFR 111.79 - Employment of broker who has lost license.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Employment of broker who has lost license. 111.79... Monetary Penalty in Lieu of Suspension or Revocation § 111.79 Employment of broker who has lost license... petition will not be approved unless the Assistant Commissioner is satisfied that the petitioner...

  2. 28 CFR 79.53 - Proof of employment as a miller.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of employment as a miller. 79.53 Section 79.53 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE RADIATION... that the employment history for the time period indicated in records listed in paragraph (a) of...

  3. 28 CFR 79.63 - Proof of employment as an ore transporter.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of employment as an ore transporter. 79.63 Section 79.63 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE... employment history for the time period indicated in such records will be presumed to be correct. If...

  4. 28 CFR 79.43 - Proof of employment as a miner.

    Science.gov (United States)

    2010-07-01

    ... Security Administration exist that indicate the claimant's work history, the Program will estimate the... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of employment as a miner. 79.43 Section 79.43 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE...

  5. 45 CFR 79.16 - Disqualification of reviewing official or ALJ.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Disqualification of reviewing official or ALJ. 79... PROGRAM FRAUD CIVIL REMEDIES § 79.16 Disqualification of reviewing official or ALJ. (a) A reviewing... with the ALJ a motion for disqualification of a reviewing official or an ALJ. Such motion shall...

  6. 29 CFR 1960.79 - Self-evaluations of occupational safety and health programs.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Self-evaluations of occupational safety and health programs. 1960.79 Section 1960.79 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health...

  7. 9 CFR 79.7 - Waiver of requirements for scrapie control pilot projects.

    Science.gov (United States)

    2010-01-01

    ... contains testing or other procedures that indicate that an animal, despite meeting the definition of high... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Waiver of requirements for scrapie control pilot projects. 79.7 Section 79.7 Animals and Animal Products ANIMAL AND PLANT HEALTH...

  8. Corrosion mechanism of 13Cr stainless steel in completion fluid of high temperature and high concentration bromine salt

    Science.gov (United States)

    Liu, Yan; Xu, Lining; Lu, Minxu; Meng, Yao; Zhu, Jinyang; Zhang, Lei

    2014-09-01

    A series of corrosion tests of 13Cr stainless steel were conducted in a simulated completion fluid environment of high temperature and high concentration bromine salt. Corrosion behavior of specimens and the component of corrosion products were investigated by means of scanning electron microscope (SEM), confocal laser scanning microscopy (CLSM) and X-ray photoelectron spectroscopy (XPS). The results indicate that 13Cr steel suffers from severe local corrosion and there is always a passive halo around every pit. The formation mechanism of the passive halo is established. OH- ligand generates and adsorbs in a certain scale because of abundant OH- on the surface around the pits. Passive film forms around each pit, which leads to the occurrence of passivation in a certain region. Finally, the dissimilarities in properties and morphologies of regions, namely the pit and its corresponding passive halo, can result in different corrosion sensitivities and may promote the formation of macroscopic galvanic pairs

  9. Fission and nuclear fragmentation of silver and bromine nuclei by photons of 1-6 GeV

    International Nuclear Information System (INIS)

    The studies of fission and fragmentation of silver and bromine nuclei by Bremsstrahlung photons of 1.6 GeV energy range are presented. The Il ford-KO nuclear emulsion submitted to Bremsstrahlung beams in Deutsches Elektronen Synchrotron (DESY) with total doses of 10'' equivalent photons, was used for nuclear fragment detection. The discrimination of fission and fragmentation events was done analysing angular distribution, range and angles between fragments. The results of fragment range distributions, angular distributions, distributions of angles between fragments, distributions of ratio between range, velocity distributions forward/backward ratio, cross sections of fission and fragmentation, nuclear fissionability and ternary fission frequency are presented and discussed. (M.C.K.)

  10. Variation in concentrations of organochlorines and brominated flame retardants among eggs in abandoned clutches of a terrestrial raptor.

    Science.gov (United States)

    Bustnes, Jan O; Bangjord, Georg; Yoccoz, Nigel G

    2015-01-01

    Bird eggs are often used to measure various pollutants in monitoring programs. In protected species, however, it might only be possible to collect eggs abandoned by the parent birds. In order to assess the appropriateness of abandoned eggs for contaminant monitoring we examined intra-clutch variation in concentrations of 24 halogenated organic pollutants (16 organochlorines [OCs] and 8 brominated flame retardants) in six abandoned tawny owl (Strix aluco) clutches from central Norway. The variation among eggs within a clutch was low for nearly all compounds (intra-class correlation >0.9 both for lipid- and wet weight). This study suggests that abandoned eggs provide a relatively reliable measurement of lipophilic pollutants in clutches of terrestrial raptors such as the tawny owl. PMID:25463262

  11. Atmospheric bromine flux from the coastal Abu Dhabi sabkhat: A ground-water mass-balance investigation

    Science.gov (United States)

    Wood, W.W.; Sanford, W.E.

    2007-01-01

    A solute mass-balance study of ground water of the 3000 km2 coastal sabkhat (salt flats) of the Emirate of Abu Dhabi, United Arab Emirates, documents an annual bromide loss of approximately 255 metric tons (0.0032 Gmoles), or 85 kg/km2. This value is an order of magnitude greater than previously published direct measurements from the atmosphere over an evaporative environment of a salar in Bolivia. Laboratory evidence, consistent with published reports, suggests that this loss is by vapor transport to the atmosphere. If this bromine flux to the atmosphere is representative of the total earth area of active salt flats then it is a significant, and generally under recognized, input to the global atmospheric bromide flux.

  12. Determination of bromine, chlorine and iodine in environmental aqueous samples by epithermal neutron activation analysis and Compton suppression

    Science.gov (United States)

    Landsberger, S.; O'Kelly, D. J.; Braisted, J.; Panno, S.

    2006-01-01

    Halides, particularly Br- and Cl-, have been used as indicators of potential sources of Na+ and Cl- in surface water and groundwater with limited success. Contamination of groundwater and surface water by Na+ and Cl- is a common occurrence in growing urban areas and adversely affects municipal and private water supplies in Illinois and other states, as well as vegetation in environmentally sensitive areas. Neutron activation analysis (NAA) can be effectively used to determine these halogens, but often the elevated concentrations of sodium and chlorine in water samples can give rise to very high detection limits for bromine and iodine due to elevated backgrounds from the activation process. We present a detailed analytical scheme to determine Cl, Br and I in aqueous samples with widely varying Na and Cl concentrations using epithermal NAA in conjunction with Compton suppression. ?? 2006 Akade??miai Kiado??.

  13. Antiproton Target

    CERN Multimedia

    1980-01-01

    Antiproton target used for the AA (antiproton accumulator). The first type of antiproton production target used from 1980 to 1982 comprised a rod of copper 3mm diameter and 120mm long embedded in a graphite cylinder that was itself pressed into a finned aluminium container. This assembly was air-cooled and it was used in conjunction with the Van der Meer magnetic horn. In 1983 Fermilab provided us with lithium lenses to replace the horn with a view to increasing the antiproton yield by about 30%. These lenses needed a much shorter target made of heavy metal - iridium was chosen for this purpose. The 50 mm iridium rod was housed in an extension to the original finned target container so that it could be brought very close to the entrance to the lithium lens. Picture 1 shows this target assembly and Picture 2 shows it mounted together with the lithium lens. These target containers had a short lifetime due to a combination of beam heating and radiation damage. This led to the design of the water-cooled target in...

  14. Identification of Cyproheptadine as an Inhibitor of SET Domain Containing Lysine Methyltransferase 7/9 (Set7/9) That Regulates Estrogen-Dependent Transcription.

    Science.gov (United States)

    Takemoto, Yasushi; Ito, Akihiro; Niwa, Hideaki; Okamura, Mutsumi; Fujiwara, Takashi; Hirano, Tomoya; Handa, Noriko; Umehara, Takashi; Sonoda, Takeshi; Ogawa, Kenji; Tariq, Mohammad; Nishino, Norikazu; Dan, Shingo; Kagechika, Hiroyuki; Yamori, Takao; Yokoyama, Shigeyuki; Yoshida, Minoru

    2016-04-28

    SET domain containing lysine methyltransferase 7/9 (Set7/9), a histone lysine methyltransferase (HMT), also methylates non-histone proteins including estrogen receptor (ER) α. ERα methylation by Set7/9 stabilizes ERα and activates its transcriptional activities, which are involved in the carcinogenesis of breast cancer. We identified cyproheptadine, a clinically approved antiallergy drug, as a Set7/9 inhibitor in a high-throughput screen using a fluorogenic substrate-based HMT assay. Kinetic and X-ray crystallographic analyses revealed that cyproheptadine binds in the substrate-binding pocket of Set7/9 and inhibits its enzymatic activity by competing with the methyl group acceptor. Treatment of human breast cancer cells (MCF7 cells) with cyproheptadine decreased the expression and transcriptional activity of ERα, thereby inhibiting estrogen-dependent cell growth. Our findings suggest that cyproheptadine can be repurposed for breast cancer treatment or used as a starting point for the discovery of an anti-hormone breast cancer drug through lead optimization. PMID:27088648

  15. The Effects of Oxy-firing Conditions on Gas-phase Mercury Oxidation by Chlorine and Bromine

    Energy Technology Data Exchange (ETDEWEB)

    Buitrago, Paula; Silcox, Geoffrey

    2010-06-30

    Bench-scale experiments were conducted in a quartz-lined, natural gas-fired reactor with the combustion air replaced with a blend of 27 mole percent oxygen, with the balance carbon dioxide. Quench rates of 210 and 440 K/s were tested. In the absence of sulfur dioxide, the oxy-firing environment caused a remarkable increase in oxidation of mercury by chlorine. At 400 ppm chlorine (as HCl equivalent), air-firing results in roughly 5 percent oxidation. At the same conditions with oxy-firing, oxidation levels are roughly 80 percent. Oxidation levels with bromine at 25 and 50 ppm (as HBr equivalent) ranged from 80 to 95 percent and were roughly the same for oxy- and air-firing conditions. Kinetic calculations of levels of oxidation at air- and oxy-conditions captured the essential features of the experimental results but have not revealed a mechanistic basis for the oxidative benefits of oxy-firing conditions. Mixtures of 25 ppm bromine and 100 and 400 ppm chlorine gave more than 90 percent oxidation. At all conditions, the effects of quench rate were not significant. The presence of 500 ppm SO2 caused a dramatic decline in the levels of oxidation at all oxy-fired conditions examined. This effect suggests that SO2 may be preventing oxidation in the gas phase or preventing oxidation in the wetconditioning system that was used in quantifying oxidized and elemental mercury concentrations. Similar effects of SO2 have been noted with air-firing. The addition of sodium thiosulfate to the hydroxide impingers that are part of wet conditioning systems may prevent liquid-phase oxidation from occurring.

  16. Brominated flame retardants (BFRs) in indoor and outdoor air in a community in Guangzhou, a megacity of southern China.

    Science.gov (United States)

    Ding, Nan; Wang, Tao; Chen, She-Jun; Yu, Mei; Zhu, Zhi-Cheng; Tian, Mi; Luo, Xiao-Jun; Mai, Bi-Xian

    2016-05-01

    Indoor environments contribute a significant portion of human exposure to brominated flame retardants (BFRs) because of their extensive use in various household products. This study investigates the occurrence of a number of BFRs in the indoor and outdoor air in a megacity in southern China, in which little information on indoor BFRs contamination is available. The estimated total PBDE concentrations ranged from 1.43 to 57 pg/m(3) indoors and from 1.21 to 1522 pg/m(3) outdoors. The indoor concentrations of lower brominated PBDEs that are mainly derived from the technical penta- and octa-BDE mixtures were higher than or comparable to the outdoors, while the indoor levels of DecaBDEs and decabromodiphenyl ethane (DBDPE) were apparently lower than the outdoors. The seasonal variations of BFR concentrations indicated that evaporation from old indoor products is the primary source of Penta- and OctaBDEs in the air, whereas most DecaBDEs and DBDPE concentrations showing weak temperature-dependence are largely released from industrial activities. The PBDE congener profiles in the air were generally similar, which were dominated by BDE209, 28, and 47; whereas the appreciable indoor-outdoor differences in the compositions are possibly due to emission sources, photochemical degradation, or congener-specific transport of BFRs in the indoor and outdoor air. Significant correlations between the indoor and outdoor BFRs were observed suggesting the exchange of BFRs between the two compartments, which are more noticeable for PentaBDEs and DecaBDEs with strong indoor and outdoor emission sources, respectively. This study provides significant insights into the sources of BFRs in urban air in China. PMID:26952274

  17. Ranges of Iodine and Bromine Isotopes Produced in the Interaction of High-Energy Protons with Uranium

    International Nuclear Information System (INIS)

    Conventional range experiments using a thick uranium foil together with aluminium catchers and monitors are carried out at the two CERN accelerators with 0.55-GeV and 18.2-GeV protons. Iodine (or bromine) is chemically isolated and separated in the CERN radioisotope separator. This gives carrier-free samples containing essentially only one pure radioactive isotope. The chemical yield is determined also. The analysis of the data gives directly the range for each isotope in uranium. All iodine isotopes have the same range at 0.55-GeV proton energy, i.e. they are all produced in a fission process. It was known previously that neutron-rich iodine isotopes have about the same range whether the proton energy is above or below I GeV, and that neutron-deficient iodine isotopes show a drastic decrease of about one half when the proton energy increases above 1 GeV. It is shown that this decrease in range occurs rather suddenly, giving a step-function in the range - versus - iodine isotopic mass curve. The neutron-deficient isotopes having a decreased range above 1-GeV proton energy are the same as those for which a strong increase in their excitation function above 1 GeV has been observed. Bromine isotopes show essentially the same range behaviour. The strong increase in the production of neutron.-deficient isotopes is again observed at high bombarding energies. The discussion will concentrate on these neutron-deficient isotopes. They are produced essentially only above 1 GeV and have at the higher combarding energy only about one half the range of normal fission products, indicating that they are produced by a process other than fission. These findings will be discussed in the light of ''spallation'' and ''fragmentation'' models, both terms being redefined. (author)

  18. Levels of brominated flame retardants and other pesistent organic pollutants in breast milk samples from Limpopo province, South Africa

    International Nuclear Information System (INIS)

    The non-occupational exposure to brominated flame retardants, and other persistent organic pollutants (POPs) was studied by collecting human breast milk samples from mothers residing in Thohoyandou area, a rural district in the Limpopo Province, northern part of South Africa (SA). Of all collected samples to be analysed (n = 28), those with large enough milk volumes, (n = 14) were quantified for polybrominated diphenyl ethers (PBDEs) (9 congeners: BDE-28, 47, 66, 99, 100, 138, 153, 154, and 183) and hexabromocyclododecane (HBCD) on a GC equipped with dual capillary columns and dual electron-capture detectors (ECD). The levels of PBDE congeners (median sumBDE 1.3 ng/g of lipids) and of HBCD were not far from levels generally found in European studies, and this study may be the first report on the presence of PBDEs and HBCD in SA breast milk. On a congener basis, the finding of comparably high BDE-183 levels suggests a specific PBDE usage, or contamination situation in SA. Apart from BFRs, the high DDT levels found in the breast milk from this area (median and maximum sumDDT levels of about 4 600 and over 20 000 ng/g of lipids, respectively; n = 28) have earlier been reported. In addition, other POPs (PCBs, HCB and HCHs) were found in SA breast milk, at relatively low levels. To conclude, measurable levels of PBDEs and HBCD, and a specific BDE congener pattern, were found in breast milk from the Limpopo province, SA. A number of other POPs, including DDTs in high levels, were also present. - Highlights: → Persistent organic pollutants (POPs) were analysed in South African breast milk. → Focus of interest were brominated flame retardants (BRFs). → Sampling area was the rural Limpopo Province, northern SA. → Probably the first reported African data on BFRs (PBDEs, HBCD) in breast milk. → Reported BFR data similar to European levels.

  19. In vitro effects of brominated flame retardants and metabolites on CYP17 catalytic activity: A novel mechanism of action?

    International Nuclear Information System (INIS)

    Fire incidents have decreased significantly over the last 20 years due, in part, to regulations requiring addition of flame retardants (FRs) to consumer products. Five major classes of brominated flame retardants (BFRs) are hexabromocyclododecane isomers (HBCDs), tetrabromobisphenol-A (TBBPA) and three commercial mixtures of penta-, octa- and deca-polybrominated diphenyl ether (PBDE) congeners, which are used extensively as commercial FR additives. Furthermore, concentrations of PBDEs have been rapidly increasing during the 1999s in human breast milk and a number of endocrine effects have been reported. We used the H295R human adrenocortical carcinoma cell line to assess possible effects of some of these BFRs (PBDEs and several of their hydroxylated (OH) and methoxylated (CH3O) metabolites or analogues), TBBPA and brominated phenols (BPs) on the combined 17α-hydroxylase and 17,20-lyase activities of CYP17. CYP17 enzyme catalyzes an important step in sex steroidogenesis and is responsible for the biosynthesis of dehydroepiandrosterone (DHEA) and androstenedione in the adrenals. In order to study possible interactions with BFRs, a novel enzymatic method was developed. The precursor substrate of CYP17, pregnenolone, was added to control and exposed H295R cells, and enzymatic production of DHEA was measured using a radioimmunoassay. In order to avoid pregnenolone metabolism via different pathways, specific chemical inhibitor compounds were used. None of the parent/precursor BFRs had a significant effect (P 3O group eliminated this cytotoxic effect, but CYP17 activity measured as DHEA production was still significantly inhibited. Other OH- or CH3O-PBDE analogues were used to elucidate possible structural properties behind this CYP17 inhibition and associated cytotoxicity, but no distinct structure activity relationship could be determined. These in vitro results indicate that OH and CH3O-PBDEs have potential to interfere with CYP17 activity for which the in vivo

  20. A potential yeast actin allosteric conduit dependent on hydrophobic core residues val-76 and trp-79.

    Science.gov (United States)

    Wen, Kuo-Kuang; McKane, Melissa; Stokasimov, Ema; Fields, Jonathon; Rubenstein, Peter A

    2010-07-01

    Intramolecular allosteric interactions responsible for actin conformational regulation are largely unknown. Previous work demonstrated that replacing yeast actin Val-76 with muscle actin Ile caused decreased nucleotide exchange. Residue 76 abuts Trp-79 in a six-residue linear array beginning with Lys-118 on the surface and ending with His-73 in the nucleotide cleft. To test if altering the degree of packing of these two residues would affect actin dynamics, we constructed V76I, W79F, and W79Y single mutants as well as the Ile-76/Phe-79 and Ile-76/Tyr-79 double mutants. Tyr or Phe should decrease crowding and increase protein flexibility. Subsequent introduction of Ile should restore packing and dampen changes. All mutants showed decreased growth in liquid medium. W79Y alone was severely osmosensitive and exhibited vacuole abnormalities. Both properties were rescued by Ile-76. Phe-79 or Tyr decreased the thermostability of actin and increased its nucleotide exchange rate. These effects, generally greater for Tyr than for Phe, were reversed by introduction of Ile-76. HD exchange showed that the mutations caused propagated conformational changes to all four subdomains. Based on results from phosphate release and light-scattering assays, single mutations affected polymerization in the order of Ile, Phe, and Tyr from least to most. Introduction of Ile-76 partially rescued the polymerization defects caused by either Tyr-79 or Phe-79. Thus, alterations in crowding of the 76-79 residue pair can strongly affect actin conformation and behavior, and these results support the theory that the amino acid array in which they are located may play a central role in actin regulation. PMID:20442407

  1. Comparison of fluorine-18 and bromine-76 imaging in positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, M.J.; Ferreira, N. [Service Hospitalier Frederic Joliot, CEA, Orsay (France)]|[Servico de Biofisica - IBILI - FMC, Coimbra (Portugal); Almeida, P.; Strul, D.; Loc`h, C.; Brulon, V.; Trebossen, R.; Maziere, B.; Bendriem, B. [Service Hospitalier Frederic Joliot, CEA, Orsay (France)

    1999-07-01

    State of the art positron emission tomography (PET) systems allow for scatter and attenuation correction. However, the size of the structure being studied and the region of interest (ROI) chosen also influence the accuracy of measurements of radioactive concentration. Furthermore, the limited spatial resolution of PET tomographs, which depends, among other factors, on the range of positrons in matter, can also contribute to a loss in quantitation accuracy. In this paper we address the influence of positron range, structure size and ROI size on the quantitation of radioactive concentration using PET. ECAT EXACT HR+ (HR+) and ECAT 953B/31 (ECAT 953B) PET systems were used in phantom acquisitions performed with two radioisotopes with different positron ranges. The 3D Hoffman phantom was scanned on both scanners with both radioisotopes, to visually analyse the image quality. A resolution phantom having six spheres of different diameters in a Plexiglas cylinder was used to calculate the values of the contrast recovery coefficient or hot spot recovery coefficient and of the spill-over or cold spot recovery coefficient under different imaging conditions used in clinical routine at our institution. Activity ratios were varied between 2 and 30 or between 0.4 and 200 by filling the spheres with fluorine-18 or bromine-76 respectively and the cylinder with {sup 11}C. Dynamic scans were performed on each scanner. Data were reconstructed using the same parameters as are used in clinical protocols. The variations in sphere and cylinder activities with time were fitted using the function M(t)=k{sub 1}.A(t)+k{sub 2}.B(t), where M(t) is the radioactivity concentration measured in an ROI placed on each sphere and A(t) and B(t) represent the true radioactivity concentrations present at time t in the spheres and in the cylinder respectively. k{sub 1} and k{sub 2} are factors representing the contrast recovery coefficient and the spill-over from surrounding activity on measurements

  2. Modeling and experimental studies to optimize the performance of a hydrogen - bromine fuel cell

    Science.gov (United States)

    Yarlagadda, Venkata Raviteja

    The regenerative Hydrogen-Bromine (H2-Br 2) fuel cells are considered to be one of the viable systems for large scale energy storage because of their high energy conversion efficiency, flexible operation, highly reversible reactions and low capital cost. The preliminary performance of a H2-Br2 fuel cell using both conventional as well as novel materials (Nafion and electrospun composite membranes along with platinum and rhodium sulfide electrocatalysts) was discussed. A maximum power density of 0.65 W/cm2 was obtained with a thicker Br 2 electrode (780 mum) and cell temperature of 45°C. The active area and wetting characteristics of Br2 electrodes were improved upon by either pre-treating with HBr or boiling them in de-ionized water. On the other hand, similar or better performances were obtained using dual fiber electrospun composite membranes (maximum power densities of 0.61 W/cm2 and 0.45 W/cm2 obtained with 25 mum and 65 mum electrospun membranes at 45°C) versus using Nafion membranes (maximum power densities of 0.52 W/cm 2 and 0.41 W/cm2 obtained with Nafion 212 and Nafion 115 membranes at 45°C). The rhodium sulfide (RhxSy) electrocatalyst proved to be more stable in the presence of HBr/Br2 than pure Pt. However, the H2 oxidation activity on RhxS y was quite low compared to that of Pt. In conclusion, a stable H 2 electrocatalyst that can match the hydrogen oxidation activity obtained with Pt and a membrane with low Br2/Br- permeability are essential to prolong the lifetime of a H2-Br2 fuel cell. A 1D mathematical model was developed to serve as a theoretical guiding tool for the experimental studies. The impact of convective and diffusive transport and kinetic rate on the performance of a H2-Br2 fuel cell is shown in this study. Of the two flow designs (flow-by and flow-through) incorporated in this study, the flow-through design demonstrated better performance, which can be attributed to the dominant convective transport inside the porous electrode. Both

  3. A Potential Yeast Actin Allosteric Conduit Dependent on Hydrophobic Core Residues Val-76 and Trp-79*

    OpenAIRE

    Wen, Kuo-Kuang; McKane, Melissa; Stokasimov, Ema; Fields, Jonathon; Rubenstein, Peter A.

    2010-01-01

    Intramolecular allosteric interactions responsible for actin conformational regulation are largely unknown. Previous work demonstrated that replacing yeast actin Val-76 with muscle actin Ile caused decreased nucleotide exchange. Residue 76 abuts Trp-79 in a six-residue linear array beginning with Lys-118 on the surface and ending with His-73 in the nucleotide cleft. To test if altering the degree of packing of these two residues would affect actin dynamics, we constructed V76I, W79F, and W79Y...

  4. Targeted Learning

    CERN Document Server

    van der Laan, Mark J

    2011-01-01

    The statistics profession is at a unique point in history. The need for valid statistical tools is greater than ever; data sets are massive, often measuring hundreds of thousands of measurements for a single subject. The field is ready to move towards clear objective benchmarks under which tools can be evaluated. Targeted learning allows (1) the full generalization and utilization of cross-validation as an estimator selection tool so that the subjective choices made by humans are now made by the machine, and (2) targeting the fitting of the probability distribution of the data toward the targe

  5. Preparation of radiopharmaceuticals labelled with bromine positron emitting isotopes for the study of dopaminergic receptors of the central nervous system using positron emission tomography

    International Nuclear Information System (INIS)

    The in vivo study of dopaminergic receptors of the central nervous system using positron emission tomography requires the preparation of radiopharmaceuticals labelled with β+ emitting isotopes. The chemical and pharmacological properties of these ligands are evaluated. Cyclotron produced 75 and 76 bromine β+ emitting isotopes are incorporated into dopaminergic ligands by electrophilic substitution using peracetic acid in a no-carrier added form. Purity, lipophilicity and specific activity are analyzed. Pharmacological criteria (specificity, saturability, displacement, localization) required for ligand-receptor binding studies are evaluated in vitro on striatal membranes and in vivo in the rat. Positron emission tomographic studies show that the study of dopaminergic D2 receptors is possible using 75 and 76 bromine labelled bromospiperone and bromolisuride. These ligands are used in physiological and pharmacological studies of the central nervous system

  6. Standard test method for determination of bromine and chlorine in UF6 and uranyl nitrate by X-Ray fluorescence (XRF) spectroscopy

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2001-01-01

    1.1 This method covers the determination of bromine (Br) and chlorine (Cl) in uranium hexafluoride (UF6) and uranyl nitrate solution. The method as written covers the determination of bromine in UF6 over the concentration range of 0.2 to 8 μg/g, uranium basis. The chlorine in UF6 can be determined over the range of 4 to 160 μg/g, uranium basis. Higher concentrations may be covered by appropriate dilutions. The detection limit for Br is 0.2 μg/g uranium basis and for Cl is 4 μg/g uranium basis. 1.2 This standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  7. Stereoselective Chlorination and Bromination of Enamides and Enamines via an Electrostatic Attraction Effect Using (1,1-Diacetoxyiodo)benzene and a Halide Source.

    Science.gov (United States)

    Xing, Linlin; Li, Chunbao

    2015-10-16

    The direct chlorination and bromination of (E)-enamines and (Z)-enamides to the corresponding (Z)-configurated α-chloroenamines, α-bromoenamines, and α-chloroenamides have been realized using NiCl2·6H2O or tetrabutyl ammonium bromide as a halide source and (1,1-diacetoxyiodo)benzene as an oxidant. The high stereoselective reactions which produce products with only (Z)-configurations can be attributed to the structure of the intermediates, the conformations of which are controlled by the electrostatic attractions between the positively charged nitrogen atoms and the oxygen atoms of the carbonyl group. This type of electrostatic effect has never been reported in olefin halogenations. For this reason, the three-membered bromonium ion is only a minor intermediate in the enamine bromination pathway. These methods open pathways to prepare α-chloroenamines and α-chloroenamides, which are not accessible via the currently used methods. PMID:26421836

  8. Evaluation of N-ethyl-N-methyl-morpholinium bromide and N-ethyl-N-methyl-pyrrolidinium bromide as bromine complexing agents in vanadium bromide redox flow batteries

    International Nuclear Information System (INIS)

    Evolution of bromine gas in the positive half cell of the Generation 2 (G2) vanadium bromide (V/Br) battery during charging is a concern which can be resolved by the use of bromine complexing agents. In this paper, for the first time, we report the effect of the addition of two quaternary ammonium bromides; N-ethyl-N-methyl-morpholinium bromide (MEM) and N-ethyl-N-methyl-pyrrolidinium bromide (MEP) to the positive and negative half cell electrolytes of the V/Br. Cyclic voltammetry (CV), linear sweep voltammetry and electrochemical impedance spectroscopy (EIS) studies showed that the addition of MEM–MEP effectively reduce Br2 vapours. Although the presence of MEM and MEP did not affect the mechanism of the electrode reactions, performance tests conducted in lab scale V/Br cells employing the VF11 cation exchange membrane resulted in lower average cell efficiencies possibly due to the increase in membrane resistance caused by membrane fouling

  9. What’s in the Pool? A Comprehensive Identification of Disinfection By-Products and Assessment of Mutagenicity of Chlorinated and Brominated Swimming Pool Water

    OpenAIRE

    Richardson, S.D.; Demarini, D.M.; Kogevinas, M; Fernandez, P.; Marco, E.; Lourencetti, C.; Balleste, C.; Heederik, D; Meliefste, K.; McKague, A.B.; Marcos, R.; Font-Ribera, L.; J.O. Grimalt; Villanueva, C M

    2010-01-01

    BACKGROUND: Swimming pool disinfectants and disinfection by-products (DBPs) have been linked to human health effects, including asthma and bladder cancer, but no studies have provided a comprehensive identification of DBPs in the water and related that to mutagenicity. OBJECTIVES: We performed a comprehensive identification of DBPs and disinfectant species in waters from public swimming pools in Barcelona, Catalonia, Spain, that disinfect with either chlorine or bromine, and we determined the...

  10. Quorum Sensing-Disrupting Brominated Furanones Protect the Gnotobiotic Brine Shrimp Artemia franciscana from Pathogenic Vibrio harveyi, Vibrio campbellii, and Vibrio parahaemolyticus Isolates†

    OpenAIRE

    Defoirdt, Tom; Crab, Roselien; Wood, Thomas K.; Sorgeloos, Patrick; Verstraete, Willy; Bossier, Peter

    2006-01-01

    Autoinducer 2 (AI-2) quorum sensing was shown before to regulate the virulence of Vibrio harveyi towards the brine shrimp Artemia franciscana. In this study, several different pathogenic V. harveyi, Vibrio campbellii, and Vibrio parahaemolyticus isolates were shown to produce AI-2. Furthermore, disruption of AI-2 quorum sensing by a natural and a synthetic brominated furanone protected gnotobiotic Artemia from the pathogenic isolates in in vivo challenge tests.

  11. Synthesis and antimicrobial evaluation of some novel 2-imino-3-(4′-carboxamido pyridyl)-5-arylidene-4-thiazolidinones and their brominated derivatives

    OpenAIRE

    Mishra P; Lukose T; Kashaw S

    2007-01-01

    Various novel 2-Imino-3-(4′-carboxamidopyridyl)-5-arylidene-4-thiazolidinones, structurally related to isonicotinic acid hydrazide (isoniazid) were synthesized and evaluated for their antimicrobial and antifungal activities together with their brominated products. Structure of the synthesized compounds was confirmed by means of their IR, 1 H-NMR spectral data and elemental analysis. Investigation of antimicrobial and antifungal activities of compounds was done by liquid dilution metho...

  12. Recent Development on Environmental Geochemistry of Bromine in Atmosphere%大气中溴的环境地球化学研究进展

    Institute of Scientific and Technical Information of China (English)

    彭炳先; 吴代赦; 李萍

    2011-01-01

    溴是大气平流层和对流层中的重要物种,能参与大气中的多种化学过程,对臭氧的损耗影响很大,同时也干扰大气的硫循环和汞循环,在大气化学中起着十分重要的作用.综述了近年来大气对流层和平流层溴的种类和含量、自然来源和人为来源,以及化学性质,并重点总结了活性溴物种BrO在大气中的存在情况及其在臭氧损耗中的作用.最后,提出了目前大气研究的不足之处和尚待深入开展研究的一些重要科学问题.%Bromine species are important components in troposphere and stratosphere, which can participate in many atmospheric chemical processes, play important role in the ozone depletion, and affect sulfur and mercury cycle of atmosphere. This paper provides an up-to-date overview of global bromine emissions from natural and anthropogenic sources, summarizes the level, species and chemistry of bromine in troposphere and stratosphere, and especially reviews the presence and important role of BrO of reactive bromine species in the ozone depletion. Finally,the shortcomings in current atmospheric research and prospect of main scientific problems are put forward.

  13. Quorum Sensing-Disrupting Brominated Furanones Protect the Gnotobiotic Brine Shrimp Artemia franciscana from Pathogenic Vibrio harveyi, Vibrio campbellii, and Vibrio parahaemolyticus Isolates†

    Science.gov (United States)

    Defoirdt, Tom; Crab, Roselien; Wood, Thomas K.; Sorgeloos, Patrick; Verstraete, Willy; Bossier, Peter

    2006-01-01

    Autoinducer 2 (AI-2) quorum sensing was shown before to regulate the virulence of Vibrio harveyi towards the brine shrimp Artemia franciscana. In this study, several different pathogenic V. harveyi, Vibrio campbellii, and Vibrio parahaemolyticus isolates were shown to produce AI-2. Furthermore, disruption of AI-2 quorum sensing by a natural and a synthetic brominated furanone protected gnotobiotic Artemia from the pathogenic isolates in in vivo challenge tests. PMID:16957276

  14. Coupled evolution of BrOx-ClOx-HOx-NOx chemistry during bromine-catalyzed ozone depletion events in the arctic boundary layer

    OpenAIRE

    M. J. Evans; Jacob, Daniel James; Atlas, E.; Cantrell, C; Eisele, F.; Flocke, F.; Fried, A.; Mauldin, R; Ridley, B.; Wert, B; Talbot, R.; Blake, D.; B. Heikes; Snow, J.; Walega, J

    2003-01-01

    Extensive chemical characterization of ozone (O3) depletion events in the Arctic boundary layer during the TOPSE aircraft mission in March–May 2000 enables analysis of the coupled chemical evolution of bromine (BrOx), chlorine (ClOx), hydrogen oxide (HOx) and nitrogen oxide (NOx) radicals during these events. We project the TOPSE observations onto an O3 chemical coordinate to construct a chronology of radical chemistry during O3 depletion events, and we compare this chronology to results from...

  15. Dependence of the vertical distribution of bromine monoxide in the lower troposphere on meteorological factors such as wind speed and stability

    OpenAIRE

    Peterson, P K; Simpson, W. R.; K. A. Pratt; P. B. Shepson; U. Frieß; J. Zielcke; Platt, U.; Walsh, S J; S. V. Nghiem

    2015-01-01

    Multiple axis differential absorption spectroscopy (MAX-DOAS) measurements of bromine monoxide (BrO) probed the vertical structure of halogen activation events during March–May 2012 at Barrow, Alaska. An analysis of the BrO averaging kernels and degrees of freedom obtained by optimal-estimation-based inversions from raw MAX-DOAS measurements reveals the information is best represented by reducing the retrieved BrO profile to two ...

  16. Multiband optical surface brightness profile decompositions of the Seyfert galaxies Mrk 79 and NGC 5548

    OpenAIRE

    Mihov, Boyko; Slavcheva-Mihova, Lyuba

    2007-01-01

    We present preliminary results of the Johnson-Cousins (U)BVRI surface brightness profile decompositions of the Seyfert galaxies Mrk 79 and NGC 5548. The profiles were modelled as a sum of a Gaussian law for the nucleus, a Sersic law for the bulge and an exponent law for the disk. A flat bar was added to the model profile of Mrk 79. The parameters and the total magnitudes of the structural components were derived.

  17. Emissions of brominated flame retardants in Asia: consideration of its potential risk form the view point of the Norwegian regulation

    Science.gov (United States)

    Kikuchi, Ryunosuke; Gerardo, Romeu; Gorbacheva, Tamara

    2010-05-01

    Flame retardants can be divided into two broad categories: additive or reactive, which can be further more divided into brominated or non-brominated sub-categories. These retardants are found in many commercial products such as computers, television sets, furniture, carpets, etc. They are of environmental concern due to their persistence, potential for bioaccumulation and widespread distribution via atmospheric transport, and possible adverse effects in wildlife and humans. Tetrabromobisphenol-A (TBBPA) is mainly used in electrical and electronic appliances (circuit board in particular), and the application of TBBPA accounts for about two thirds of the global production of brominated flame retardant (BFR). The European Union Risk Assessment does not support the restriction of TBBPA: i.e. no risk is identified for the reactive use of TBBPA such as in epoxy resin used in circuit boards. By contrast, in 2007 Norway notified the World Trade Organization of its intention to prohibit 18 substances from consumer goods (Notification No. 2007/9016/N), called the Prohibition on Certain Hazardous Substances in Consumer Products (PoHS). TBBPA is listed in this prohibition list. Marine conservation is recognized as a key issue in Norwegian fishery management e.g. wastewater management in the framework of the North Sea Declarations. TBBPA is very water-soluble, and dimethyl-TBBPA is lipophilic and may accumulate in fat. TBBPA is not readily biodegradable and can have long-term effects in the aquatic environment. Norwegian examples are summarized: TBBPA was found in marine sediment samples from Tromsø harbor (northern Norway) and in Atlantic cod from Lofoten and Varanger; TBBPA has been detected in Norwegian peregrine falcon and golden eagle eggs; and TBBPA has been detected in the blood in the general population of Norway. From these viewpoints, it can be considered that Norway needs to strictly control TBBPA emissions. In recent times, Asia has emerged as one of the leading

  18. Effect of KIOM-79 on Diabetes-Induced Myocardial Fibrosis in Zucker Diabetic Fatty Rats

    Directory of Open Access Journals (Sweden)

    Junghyun Kim

    2013-01-01

    Full Text Available KIOM-79, a herbal mixture of parched Puerariae radix, gingered Magnoliae cortex, Glycyrrhizae radix, and Euphorbiae radix, has a strong inhibitory effect on advanced glycation end products (AGEs formation. We investigated the beneficial effects of KIOM-79 on cardiac fibrosis in Zucker diabetic fatty (ZDF rats. KIOM-79 (50 or 500 mg/kg/day was orally administered for 13 weeks. AGEs formation and collagen expression in the myocardium were assessed by immunohistochemistry. The expression levels of the receptor for AGEs (RAGE, transforming growth factor-β1 (TGF-β1, collagen IV, fibronectin, urotensin II, and urotensin II receptor were examined in the myocardial tissue of ZDF rats. KIOM-79 treatment at 500 mg/kg inhibited the accumulation of AGEs, reduced RAGE mRNA and protein expression, and reduced the upregulation of cardiac fibrogenic factors, such as fibronectin and collagen IV, in heart of ZDF rats. Additionally, KIOM-79 ameliorated urotensin II/receptor gene expression in the cardiac tissue of ZDF rats. Our findings indicate that KIOM-79 diminishes cardiac fibrosis in ZDF rats by preventing AGEs accumulation and RAGE overexpression and by modulating the cardiac urotensin II/receptor pathway, which decreases the amount of profibrotic factors, such as TGF-β1, fibronectin, and collagen in cardiac tissue.

  19. Ultraviolet/Ozone as a Tool To Control Grafting Density in Surface-Initiated Controlled-Radical Polymerizations via Ablation of Bromine.

    Science.gov (United States)

    Sheridan, Richard J; Orski, Sara V; Muramoto, Shin; Stafford, Christopher M; Beers, Kathryn L

    2016-08-16

    We used an ultraviolet-ozone (UVO) cleaner to create substrates for atom-transfer radical polymerization (ATRP) with varying surface initiator coverage. We collected complementary time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) measurements to investigate the precise chemical origin of the variation in grafting density. At short exposure times, the atomic composition underwent minor changes except for the relative amount of bromine. At longer UVO exposure times, there is clear evidence of exposure-dependent surface initiator oxidation. We interpret these data as evidence of a bromine ablation process within the UVO cleaner, with additional oxidative modification of the rest of the surface. We then used these substrates to create a series of poly(methyl methacrylate) (PMMA) brushes varying in grafting density, demonstrating the utility of this tool for the control of polymer brush density. The measured brush grafting densities were correlated with the bromine concentration measured by both ToF-SIMS and XPS. XPS and brush thicknesses correlated strongly, following an exponential decay with a half-life of 18 ± 1 s. PMID:27442615

  20. Bromine and Chlorine in Aerosols and Fly Ash when Co-Firing Solid Recovered Fuel, Spruce Bark and Paper Mill Sludge in a 80MWth BFB Boiler

    Science.gov (United States)

    Vainikka, P.; Silvennoinen, J.; Yrjas, P.; Frantsi, A.; Hietanen, L.; Hupa, M.; Taipale, R.

    Aerosol and fly ash sampling was carried out at a 80MWth bubbling fluidised bed (BFB) boiler plant co-firing solid recovered fuel (SRF), spruce bark and paper mill wastewater sludge in two experimental conditions. The SRF-Bark ratio in the fuel mix was kept constant at 50%-50% on dry mass basis in both experiments but two sludge proportions were used: 15% and 4% on dry mass basis. Aerosol samples were collected from the superheater region of the boiler furnace and fly ash from the electrostatic precipitator (ESP). Na, K, Cl and S were found to be in mainly water soluble compounds in the aerosols sampled by means of a Dekati type Low Pressure Impactor (DLPI). Bromine was found in several weight percentages in aerosols and it was amongst the main elements in some of the samples collected. Bromine is assumed to mainly originate from flame retarded plastics and textiles in the SRF. According to the measurements, the fate of Br seems to be analogous to the other main halogen, Cl, and its conversion from fuel to aerosols was high, indicating a strong tendency to form bromine salts.

  1. Predictive models for water sources with high susceptibility for bromine-containing disinfection by-product formation: implications for water treatment.

    Science.gov (United States)

    Watson, Kalinda; Farré, Maria José; Birt, James; McGree, James; Knight, Nicole

    2015-02-01

    This study examines a matrix of synthetic water samples designed to include conditions that favour brominated disinfection by-product (Br-DBP) formation, in order to provide predictive models suitable for high Br-DBP forming waters such as salinity-impacted waters. Br-DBPs are known to be more toxic than their chlorinated analogues, in general, and their formation may be favoured by routine water treatment practices such as coagulation/flocculation under specific conditions; therefore, circumstances surrounding their formation must be understood. The chosen factors were bromide concentration, mineral alkalinity, bromide to dissolved organic carbon (Br/DOC) ratio and Suwannee River natural organic matter concentration. The relationships between these parameters and DBP formation were evaluated by response surface modelling of data generated using a face-centred central composite experimental design. Predictive models for ten brominated and/or chlorinated DBPs are presented, as well as models for total trihalomethanes (tTHMs) and total dihaloacetonitriles (tDHANs), and bromide substitution factors for the THMs and DHANs classes. The relationships described revealed that increasing alkalinity and increasing Br/DOC ratio were associated with increasing bromination of THMs and DHANs, suggesting that DOC lowering treatment methods that do not also remove bromide such as enhanced coagulation may create optimal conditions for Br-DBP formation in waters in which bromide is present. PMID:25163557

  2. Experimental and theoretical analysis of the kinetics of the reaction of atomic bromine with 1,4-dioxane.

    Science.gov (United States)

    Giri, Binod Raj; Roscoe, John M; González-García, Núria; Olzmann, Matthias

    2010-01-14

    The rate coefficient for the reaction of atomic bromine with 1,4-dioxane was measured from approximately 300 to 340 K using the relative rate method. Iso-octane and iso-butane were used as reference compounds, and the experiments were made in a bath of argon containing up to 210 Torr of O(2) at total pressures between 200 and 820 Torr. The rate coefficients were not affected by changes in pressure or O(2) concentration over our range of experimental conditions. The ratios of rate coefficients for the reaction of dioxane relative to the reference compound were put on an absolute basis by using the published absolute rate coefficients for the reference reactions. The variation of the experimentally determined rate coefficients with temperature for the reaction of Br with 1,4-dioxane can be given by k(1)(exp)(T) = (1.4 +/- 1.0) x 10(-11)exp[-23.0 +/- 1.8) kJ mol(-1)/(RT)] cm(3) molecule(-1) s(-1). We rationalized our experimental results in terms of transition state theory with molecular data from quantum chemical calculations. Molecular geometries and frequencies were obtained from MP2/aug-cc-pVDZ calculations, and single-point energies of the stationary points were obtained at CCSD(T)/CBS level of theory. The calculations indicate that the 1,4-dioxane + Br reaction proceeds in an overall endothermic addition-elimination mechanism via a number of intermediates. The rate-determining step is a chair-to-boat conformational change of the Br-dioxane adduct. The calculated rate coefficients, given by k(1)(calc)(T) = 5.6 x 10(-11)exp[-26.6 kJ mol(-1)/(RT)] cm(3) molecule(-1) s(-1), are in very good agreement with the experimental values. Comparison with results reported for the reactions of Br with other ethers suggests that this multistep mechanism differs significantly from that for abstraction of hydrogen from other ethers by atomic bromine. PMID:19848396

  3. Enhancement of the volcanogenic "bromine explosion" via reactive nitrogen chemistry (Kīlauea volcano, Hawai'i

    Directory of Open Access Journals (Sweden)

    G. G. Salerno

    2010-04-01

    Full Text Available Since the first detection of bromine monoxide in volcanic plumes attention has focused on the atmospheric synthesis and impact of volcanogenic reactive halogens. We report here new measurements of BrO in the volcanic plume emitted from Kīlauea volcano – the first time reactive halogens have been observed in emissions from a hotspot volcano. Observations were carried out by ground-based Differential Optical Absorption Spectroscopy in 2007 and 2008 at Pu'u'O'o crater, and at the 2008 magmatic vent that opened within Halema'uma'u crater. BrO was readily detected in the Halema'uma'u plume (average column amount of 3×1015 molec cm−2 and its abundance was strongly correlated with that of SO2. However, anticorrelation between NO2 and SO2 (and BrO abundances in the same plume strongly suggest an active role of NOx in reactive halogen chemistry. The calculated SO2/BrO molar ratio of ~1600 is comparable to observations at other volcanoes, although the BrO mixing ratio is roughly double that observed elsewhere. While BrO was not observed in the Pu'u'O'o plume this was probably merely a result of the detection limit of our measurements and based on understanding of the Summit and East Rift magmatic system we expect reactive halogens to be formed also in the Pu'u'O'o emissions. If this is correct then based on the long term SO2 flux from Pu'u'O'o we calculate that Kīlauea emits ~480 Mg yr−1 of reactive bromine and may thus represent an

  4. Inclusion of polar sea-ice emissions and sea-salt aerosol recycling of bromine into the global CAM-Chem chemistry-climate model

    Science.gov (United States)

    Fernandez, Rafael Pedro; Ordoñez, Carlos; Kinnison, Douglas; Lamarque, Jean-Francois; Saiz-Lopez, Alfonso

    2013-04-01

    The global CAM-Chem chemistry climate model has been updated by including a coupled polar module with a full halogen chemistry mechanism and time-varying organic and inorganic halogen emissions into the polar marine boundary layer. The baseline halogen CAM-Chem setup has already been validated for the tropics and mid-latitudes and includes natural sources of very short-lived (VSL) halocarbons from the oceans; reactive chlorine, bromine and iodine species; related photochemical, gas-phase and heterogeneous reactions, as well as wet and dry deposition for relevant species. The coupled polar module considers i) time-dependent sea-ice emissions of Br2 and BrCl as result of recycling over the deposited snow over sea-ice, ii) sea-salt aerosol recycling of BrONO2, BrNO2 and HOBr in the polar boundary layer and iii) improved sea-salt recycling efficiency over fresh sea-ice regions representing the contributions from blowing snow. The external brominated sources posses a 2-fold dependence on both solar zenith angle and local sea-ice cover. The time/sea-ice dependent local Br2 flux was scaled to reproduce observations of reactive bromine species over coastal Antarctica. This results in an Antarctic mean sea-ice flux of ~200 Gg Br yr-1 with maximum emissions in late spring, as a compromise between sea-ice coverage and intensity of radiation. Recycling of bromine over sea-salt aerosol is the dominant factor controlling the tropospheric vertical column density (VCD) of BrO and other inorganic bromine species. A monthly-dependent depletion factor is introduced to account for the net fraction of Br in sea-salt that is released to the atmosphere. Model results have been validated locally against measurements of BrO performed at several Antarctic stations, showing a good agreement both in the boundary layer concentrations for the entire year and the springtime maximum BrO observed in October. The seasonality and intensity of the BrO total and tropospheric columns are also in

  5. 36 CFR 51.79 - May the Director waive payment of a franchise fee or other payments?

    Science.gov (United States)

    2010-07-01

    ... payment of a franchise fee or other payments? 51.79 Section 51.79 Parks, Forests, and Public Property....79 May the Director waive payment of a franchise fee or other payments? The Director may not waive the concessioner's payment of a franchise fee or other payments or consideration required by...

  6. Mitochondrial ORF79 levels determine pollen abortion in cytoplasmic male sterile rice.

    Science.gov (United States)

    Kazama, Tomohiko; Itabashi, Etsuko; Fujii, Shinya; Nakamura, Takahiro; Toriyama, Kinya

    2016-03-01

    Cytoplasmic male sterility (CMS) is an important agricultural trait characterized by lack of functional pollen, and caused by ectopic and defective mitochondrial gene expression. The pollen function in CMS plants is restored by the presence of nuclear-encoded restorer of fertility (Rf) genes. Previously, we cloned Rf2, which restores the fertility of Lead Rice (LD)-type CMS rice. However, neither the function of Rf2 nor the identity of the mitochondrial gene causing CMS has been determined in LD-CMS rice. Here, we show that the mitochondrial gene orf79 acts as a CMS-associated gene in LD-CMS rice, similar to its role in BT-CMS rice originating from Chinsurah Boro II, and Rf2 weakly restores fertility in BT-CMS rice. We also show that RF2 promotes degradation of atp6-orf79 RNA in a different manner from that of RF1, which is the Rf gene product in BT-CMS rice. The amount of ORF79 protein in LD-CMS rice was one-twentieth of the amount in BT-CMS rice. The difference in ORF79 protein levels probably accounts for the mild and severe pollen defects in LD-CMS and BT-CMS rice, respectively. In the presence of Rf2, accumulation of ORF79 was reduced to almost zero and 25% in LD-CMS and BT-CMS rice, respectively, which probably accounts for the complete and weak fertility restoration abilities of Rf2 in LD-CMS and BT-CMS rice, respectively. These observations indicate that the amount of ORF79 influences the pollen fertility in two strains of rice in which CMS is induced by orf79. PMID:26850149

  7. Safety concept for spallation target system. JAERI/KEK joint project

    International Nuclear Information System (INIS)

    A MW-class mercury target of the spallation target generates much larger amounts of radioactive nuclides than existing spallation neutron sources. To estimate the maximum level of public exposure under the guillotine break of mercury pipelines that is one of the major accidents of the target system, the hazard analyses were carried out by using a transportation model which considers heat transmission of mercury decay heat, diffusion of evaporated radioactive nuclides, etc. In the analyses, mercury, iodine, bromine and noble gas were selected as the effective source term because of their high vapor pressures and activation levels. From the preliminary analytical results obtained under the conservative conditions of 2 m/s of the air velocity around the mercury leakage area, the maximum level of the public exposure was approximately 5.8 x 10-3 mSv. This level is negligible in comparison with 1 mSV one-year natural radiation exposure. (author)

  8. Bioactive brominated metabolites from the natural habitat and tank-maintained cuttings of the Jamaican sponge Aplysina fistularis.

    Science.gov (United States)

    Gallimore, Winklet A

    2013-06-01

    Cut specimens of the common reef sponge of the Verongid family, Aplysina fistularis, were retained in flow-through seawater tanks over a six-week period to assess the metabolite profile of the sponge when subjected to stress, compare the profile with the source material, and assess the preliminary feasibility of the protocol for sponge culture. The living specimens were harvested, extracted with MeOH/CH₂Cl₂ 1:1, and subjected to column chromatography to identify metabolites. The brominated isoxazoline compounds, aerothionin (1) and 11-oxoaerothionin (2), along with aeroplysinin 2 (3) and 2-(3,5-dibromo-4-hydroxyphenol)acetamide (4), were detected in the cuttings from the tank-maintained sponge. An examination of the metabolite profile of the sponge from the natural habitat showed that the compounds 1 and 2 were present. The identities of all the compounds were ascertained by analysis of the mass-spectral data and NMR spectra (¹H, ¹³C, HMBC, and HSQC) of the compounds, which were compared with reported data. The survival rate was 44% with limited necrosis or exposed skeletal tissue being observed in eight of the 18 cuttings, suggesting that protocol modifications would be required for culturing the sponge. PMID:23776020

  9. Brominated and organophosphate flame retardants in indoor dust of Jeddah, Kingdom of Saudi Arabia: Implications for human exposure.

    Science.gov (United States)

    Ali, Nadeem; Eqani, Syed Ali Musstjab Akber Shah; Ismail, Iqbal Mohammad Ibrahim; Malarvannan, Govindan; Kadi, Mohammad W; Albar, Hussain Mohammed Salem; Rehan, Mohammad; Covaci, Adrian

    2016-11-01

    Different flame retardants (FRs) namely polybrominated diphenyl ethers (PBDEs), emerging brominated/chlorinated flame retardants (Br/Cl FRs), and organophosphate FRs (OPFRs) were analyzed in cars, air conditioner (AC) filters and floor dust of different households from Jeddah, Kingdom of Saudi Arabia (KSA). To the best of our knowledge, this is first study in literature reporting emerging Br/Cl FRs and OPFRs in AC filter dust and also first to report on their occurrence in dust from KSA. Chlorinated alkyl phosphate, penta-BDEs, BDE-209, and decabromodiphenylethane (DBDPE) were the major chemicals in dust samples from all microenvironments. ΣOPFRs occurred at median concentrations (ng/g dust) of 15,400, 10,500, and 3750 in AC filter, car and house floor dust, respectively. For all analyzed chemicals, relatively lower levels were observed in floor dust than car and AC filter dust. The profiles of FRs in car dust were different from AC filter and floor dust, which reflected their wider application as FR and plasticizer in variety of household and commercial products. For toddlers, assuming high dust intake and 95th percentile concentrations, the computed exposure estimation for BDE-99 was higher than RfD values. PMID:27343946

  10. Bromine and iodine observation over the tropical Eastern and Western Pacific: impacts on atmospheric ozone and mercury

    Science.gov (United States)

    Dix, Barbara; Volkamer, Rainer; Baidar, Sunil; Koenig, Theodore; Coburn, Sean; Ortega, Ivan; Huey, Greg; Apel, Eric; Carpenter, Lucy; Evans, Mathew; Sherwin, Tomas; Kinnison, Doug; Lamarque, Jean-Francois; Saiz-Lopez, Alfonso; Pierce, Brad; Jacob, Daniel; Schmidt, Johan; Atlas, Elliot; Pan, Laura; Salawitch, Ross

    2015-04-01

    Tropospheric halogens catalytically destroy ozone, modify oxidative capacity, and oxidize atmospheric mercury. About 75% of the global tropospheric O3 loss occurs at tropical latitudes, where O3 radiative forcing is most sensitive to changes in O3. Here we report on BrO and IO observations by the CU Airborne MAX-DOAS instrument aboard the NSF/NCAR GV aircraft during the Tropical Ocean tRoposphere Exchange of Reactive halogen species and Oxygenated VOC (TORERO) and CONvective TRansport of Active Species in the Tropics (CONTRAST) field campaigns. We have measured BrO and IO vertical profiles over the tropical and sub-tropical Western and Eastern Pacific Ocean, including a detection of IO in the UTLS and lower stratosphere. Observed IO abundances are 2-3 times higher in the Southern hemisphere than in the Northern hemisphere free troposphere. Measurements in the lower stratosphere and tropical UTLS provide the first quantification of IO in these layers by limb observations of scattered sunlight. BrO concentrations increase with altitude and are 2-4 times higher than predicted by models. We compare our observations with predictions from the global models CAM-Chem, GEOS-Chem and RAQMS. Our measurements indicate that these halogens are responsible for 34% of the column integrated loss of tropospheric O3. At the observed levels bromine oxidizes mercury at up to 3.5 times faster rates, and at lower altitudes than models predict, which has implications for global mercury distributions and deposition to ecosystem.

  11. Brominated flame retardants and perfluorinated chemicals, two groups of persistent contaminants in Belgian human blood and milk

    Energy Technology Data Exchange (ETDEWEB)

    Roosens, Laurence [Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); D' Hollander, Wendy; Bervoets, Lieven [Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Reynders, Hans; Van Campenhout, Karen [Environment and Health Unit, Department of Environment, Nature and Energy, Flemish Government - Koning Albert II-laan 20, Bus 8, 1000 Brussels (Belgium); Cornelis, Christa; Van Den Heuvel, Rosette; Koppen, Gudrun [Unit Environmental Risk and Health, Flemish Institute of Technological Research (VITO), Boeretang 200, 2400 Mol (Belgium); Covaci, Adrian, E-mail: adrian.covaci@ua.ac.b [Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

    2010-08-15

    We assessed the exposure of the Flemish population to brominated flame retardants (BFRs) and perfluorinated compounds (PFCs) by analysis of pooled cord blood, adolescent and adult serum, and human milk. Levels of polybrominated diphenyl ethers (PBDEs) in blood (range 1.6-6.5 ng/g lipid weight, lw) and milk (range 2.0-6.4 ng/g lw) agreed with European data. Hexabromocyclododecane ranged between <2.1-5.7 ng/g lw in milk. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) dominated in blood and ranged between 1 and 171 ng/mL and <0.9-9.5 ng/mL, respectively. Total PFC levels in milk ranged between <0.5-29 ng/mL. A significant increase in PBDE concentrations was detected from newborns (median 2.1) to the adolescents and adults (medians 3.8 and 4.6 ng/g lw, respectively). An identical trend was observed for PFOS, but not for PFOA. We estimated that newborn exposure to BFRs and PFCs occurs predominantly post-natally, whereas placental transfer has a minor impact on the body burden. - The exposure to BFRs and PFCs of general Flemish population has been assessed throughout several age groups.

  12. Three decades (1983-2010) of contaminant trends in East Greenland polar bears (Ursus maritimus). Part 2: brominated flame retardants.

    Science.gov (United States)

    Dietz, Rune; Rigét, Frank F; Sonne, Christian; Born, Erik W; Bechshøft, Thea; McKinney, Melissa A; Drimmie, Robert J; Muir, Derek C G; Letcher, Robert J

    2013-09-01

    Brominated flame retardants were determined in adipose tissues from 294 polar bears (Ursus maritimus) sampled in East Greenland in 23 of the 28years between 1983 and 2010. Significant linear increases were found for sum polybrominated diphenyl ether (ΣPBDE), BDE100, BDE153, and hexabromocyclododecane (HBCD). Average increases of 5.0% per year (range: 2.9-7.6%/year) were found for the subadult polar bears. BDE47 and BDE99 concentrations did not show a significant linear trend over time, but rather a significant non-linear trend peaking between 2000 and 2004. The average ΣPBDE concentrations increased 2.3 fold from 25.0ng/g lw (95% C.I.: 15.3-34.7ng/g lw) in 1983-1986 to 58.5ng/g lw (95% C.I.: 43.6-73.4ng/g lw) in 2006-2010. Similar but fewer statistically significant trends were found for adult females and adult males likely due to smaller sample size and years. Analyses of δ(15)N and δ(13)C stable isotopes in hair revealed no clear linear temporal trends in trophic level or carbon source, respectively, and non-linear trends differed among sex and age groups. These increasing concentrations of organobromine contaminants contribute to complex organohalogen mixture, already causing health effects to the East Greenland polar bears. PMID:23137556

  13. Brominated flame retardants (BFRs) in breast milk and associated health risks to nursing infants in Northern Tanzania.

    Science.gov (United States)

    Müller, M H B; Polder, A; Brynildsrud, O B; Lie, E; Løken, K B; Manyilizu, W B; Mdegela, R H; Mokiti, F; Murtadha, M; Nonga, H E; Skaare, J U; Lyche, J L

    2016-01-01

    The main aim of this study was to assess brominated flame retardants (BFRs) in breast milk in the Northern parts of Tanzania. Ninety-five colostrum samples from healthy, primiparous mothers at Mount Meru Regional Referral Hospital (MMRRH), Arusha Tanzania, were analyzed for polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), hexabromobenzene (HBB), (2,3-dibromopropyl) (2,4,6-tribromophenyl) ether (DPTE), pentabromoethylbenzene (PBEB) and 2,3,4,5,6-pentabromotoluene (PBT). The Ʃ7PBDE (BDE 28, 47, 99, 100, 153, 154, 183) ranged from below level of detection (

  14. Evaluation of 3D-human skin equivalents for assessment of human dermal absorption of some brominated flame retardants.

    Science.gov (United States)

    Abdallah, Mohamed Abou-Elwafa; Pawar, Gopal; Harrad, Stuart

    2015-11-01

    Ethical and technical difficulties inherent to studies in human tissues are impeding assessment of the dermal bioavailability of brominated flame retardants (BFRs). This is further complicated by increasing restrictions on the use of animals in toxicity testing, and the uncertainties associated with extrapolating data from animal studies to humans due to inter-species variations. To overcome these difficulties, we evaluate 3D-human skin equivalents (3D-HSE) as a novel in vitro alternative to human and animal testing for assessment of dermal absorption of BFRs. The percutaneous penetration of hexabromocyclododecanes (HBCD) and tetrabromobisphenol-A (TBBP-A) through two commercially available 3D-HSE models was studied and compared to data obtained for human ex vivo skin according to a standard protocol. No statistically significant differences were observed between the results obtained using 3D-HSE and human ex vivo skin at two exposure levels. The absorbed dose was low (less than 7%) and was significantly correlated with log Kow of the tested BFR. Permeability coefficient values showed increasing dermal resistance to the penetration of γ-HBCD>β-HBCD>α-HBCD>TBBPA. The estimated long lag times (>30 min) suggests that frequent hand washing may reduce human exposure to HBCDs and TBBPA via dermal contact. PMID:26232142

  15. Application of supercritical water to decompose brominated epoxy resin and environmental friendly recovery of metals from waste memory module.

    Science.gov (United States)

    Li, Kuo; Xu, Zhenming

    2015-02-01

    Waste Memory Modules (WMMs), a particular kind of waste printed circuit board (WPCB), contain a high amount of brominated epoxy resin (BER), which may bring a series of environmental and health problems. On the other hand, metals like gold and copper are very valuable and are important to recover from WMMs. In the present study, an effective and environmental friendly method using supercritical water (SCW) to decompose BER and recover metals from WMMs was developed instead of hydrometallurgy or pyrometallurgy simultaneously. Experiments were conducted under external-catalyst-free conditions with temperatures ranging from 350 to 550 °C, pressures from 25 to 40 MPa, and reaction times from 120 to 360 min in a semibatch-type reactor. The results showed that BER could be quickly and efficiently decomposed under SCW condition, and the mechanism was possibly free radical reaction. After the SCW treatments, the glass fibers and metal foils in the solid residue could be easily liberated and recovered, respectively. The metal recovery rate reached 99.80%. The optimal parameters were determined as 495 °C, 33 MPa, and 305 min on the basis of response surface methodology (RSM). This study provides an efficient and environmental friendly approach for WMMs recycling compared with electrolysis, pyrometallurgy, and hydrometallurgy. PMID:25582426

  16. Fission and fragmentation of silver and bromine nuclei by 1-6 GeV energy photons

    International Nuclear Information System (INIS)

    Fission and fragmentation of silver and bromine nuclei induced by bremsstrahlung photons in the maximum energy range of 1-6 GeV are studied. A special technique of nuclear emulsion for the highly ionizing nuclear fragment detection is used in the discrimination between nuclear fission and fragmentation events. Films of Ilford-KO nuclear emulsion (approximatelly 1020 atoms/cm2 of Ag, Br) which had been exposed to bremsstrahlung beams in 'Deutsches Elektronen Synchrotron' (DESY, Hamburg) with total doses of approximatelly 1011 equivalent photons are used. Through a detailed analysis of range, angular and angle between fragment distributions, and empirical relations which permit to estimate nuclear fragment energy, range and velocity, the discrimination between fission and fragmentation events is made. Results related to fragment range distribution, angular distribution, distribution of angle between fragments, distribution of ratio between ranges, velocity distributions, forward/backward ratio, fission and fragmentation cross sections, nuclear fissionability and ternary fission frequency are presented and discussed. The results show that the mean photofragmentation cross section in the internal 1-6 GeV (0,09+-0,02mb) is significant when compared to the photofission (0,29+-0,05mb). It is also shown that the mean photofission cross section between 1 and 6 GeV is great by a factor of approximatelly 10 when compared to the foreseen by the cascade-evaporation nuclear model for monoenergetic photons of 0,6 GeV. (L.C.)

  17. ICP-MS measurements of iodine and bromine in environmental samples collected along the Kuji River, Japan

    International Nuclear Information System (INIS)

    From a viewpoint of monitoring the distribution and transfer of long-lived radioiodine (129I) and possible hazardous brominated substances, I and Br contents in various environmental samples collected in the Kuji River area, Japan, were studied by ICP-MS. The feature of the change in concentrations of I and Br, as well as those of other general properties such as pH etc., in Kuji River watershed were coincident with each other. It is considered from the obtained data that the environmental conditions, especially those of the soil of the area, mainly control the distribution of I and Br in the river water. The circulation characteristics of I and Br showed different features in different transfer media, which could be ascribed to the different chemical properties of these elements in each media. It was also shown that the distributions of I and Br are varied even within a small zone of about 20 km width around a high mountain of this area, which is also considered to reflect the environmental characteristics of the district. (author)

  18. Selected chlorobornanes, polychlorinated naphthalenes and brominated flame retardants in Bjørnøya (Bear Island) freshwater biota.

    Science.gov (United States)

    Evenset, Anita; Christensen, Guttorm N; Kallenborn, Roland

    2005-08-01

    Levels of selected sparsely investigated persistent organic pollutants (POPs) have been measured in organisms from two Arctic lakes on Bjørnøya (Bear Island). Elevated levels of chlorobornanes (CHBs) (up to 46.7 ng/g wet weight=ww), polybrominated diphenyl ethers (PBDEs) (up to 27.2 ng/g ww), polybrominated biphenyls (PBBs) (up to 1.1 ng/g ww) and polychlorinated naphthalenes (PCNs, only 4 congeners) (up to 62.7 pg/g ww), were measured in biota from Lake Ellasjøen. In Lake Øyangen, located only 5 km north of Ellasjøen, levels of these contaminants were significantly lower. delta(15)N-values were 7-10 per thousand higher in organisms from Ellasjøen as compared to Øyangen. This is attributed to biological inputs related to seabird activities. The present study illustrates that contaminants such as CHBs, brominated flame retardants and PCNs accumulate in the Ellasjøen food web in a manner similar to PCBs and conventional organochlorine pesticides. Transport mechanisms that control PCB and DDT distributions, i.e. atmospheric long-range transport and biotransport by seabirds, are also relevant for the contaminants investigated in the present study. PMID:15862396

  19. Trophodynamics of hexabromocyclododecanes and several other non-PBDE brominated flame retardants in a freshwater food web.

    Science.gov (United States)

    Wu, Jiang-Ping; Guan, Yun-Tao; Zhang, Ying; Luo, Xiao-Jun; Zhi, Hui; Chen, She-Jun; Mai, Bi-Xian

    2010-07-15

    Several currently used non-polybrominated diphenyl ether (PBDE) brominated flame retardants (BFRs), including hexabromocyclododecanes (HBCDs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE), hexabromobenzene (HBB), pentabromoethylbenzene (PBEB), and pentabromotoluene (PBT), are examined in the components of a freshwater food web from an electronic waste recycling site, South China. All these BFRs are detectable in the food web, with average concentrations of 13.9-868, 1.71-518, Food web magnification is observed for (+)-alpha-, (-)-alpha-, (+/-)-alpha-, and total HBCDs, and HBB, with trophic magnification factors (TMFs) of 2.22, 2.18, 2.19, 1.82, and 1.46, respectively; whereas there is trophic dilution of BTBPE and PBT through the food web. The TMFs for (+)-alpha-, (-)-alpha-, and (+/-)-alpha-HBCDs are comparable to those of PBDEs detected previously in the same food web. Biota samples show a shift from gamma- toward alpha-HBCD compared with the suspended particles, sediment, and HBCD technical mixtures, with a significant increase of alpha-HBCD on ascending trophic levels. Except for alpha-HBCD in suspended particles and sediment, all the HBCD enantiomers detected are nonracemic in the environmental matrix. In biota, nonracemic residues of alpha-HBCD were observed in mud carp and crucian carp; beta-HBCD in prawn, mud carp, and crucian carp; and gamma-HBCD in water snake, with preferences for (+)-alpha-, (-)-beta-, and (+)-gamma-HBCDs. PMID:20575536

  20. A comparative study of carbon felt and activated carbon based electrodes for sodium polysulfide/bromine redox flow battery

    International Nuclear Information System (INIS)

    Carbon felt (CF) and activated carbon (AC) based electrodes for sodium polysulfide/bromine redox flow battery (PSB) were prepared and compared with a laboratory scale PSB flow cell in terms of structure and application performances. The structural properties of the two types of electrodes were characterized by filamentary analog and BET analysis, respectively. Catalyst coating, discharge behavior analysis and thermogravimetric analysis-mass spectrometry (TG-MS) were carried out to make out the different dominant factor in the application performances of the two materials. Compared to AC based electrode (ACE), despite of the relatively low surface area, CF demonstrates almost the same application performances, much more gains in electrochemical activity towards negative half-cell reactions by catalyst coating, and more even discharge voltage curve and stable cycling performance. At current density of 40 mA cm-2, an average energy efficiency of up to 81% over 50 cycles (about 600 h) has been achieved with cobalt coated CF, but with ACE only 64.7% within 16 cycles, which decreases quickly due to the loss of surface area resulted from sulfur depositing. The difference in structure related to mass transport makes the application performances gap between the two types of materials in PSB