Sample records for lead bromides

  1. Active Control of Interface Shape During the Crystal Growth of Lead Bromide

    NASA Technical Reports Server (NTRS)

    Duval, W. M. B.; Batur, C.; Singh, N. B.

    2003-01-01

    A thermal model for predicting and designing the furnace temperature profile was developed and used for the crystal growth of lead bromide. The model gives the ampoule temperature as a function of the furnace temperature, thermal conductivity, heat transfer coefficients, and ampoule dimensions as variable parameters. Crystal interface curvature was derived from the model and it was compared with the predicted curvature for a particular furnace temperature and growth parameters. Large crystals of lead bromide were grown and it was observed that interface shape was in agreement with the shape predicted by this model.

  2. Strategies for the removal of halides from drinking water sources, and their applicability in disinfection by-product minimisation: a critical review.

    PubMed

    Watson, K; Farré, M J; Knight, N

    2012-11-15

    The presence of bromide (Br(-)) and iodide (I(-)) in source waters leads to the formation of brominated and iodinated disinfection by-products (DBPs), which are often more toxic than their chlorinated analogues. The increasing scarcity of water resources in Australia is leading to use of impaired and alternative water supplies with high bromide and iodide levels, which may result in the production of more brominated and iodinated DBPs. This review aims to provide a summary of research into bromide and iodide removal from drinking water sources. Bromide and iodide removal techniques have been broadly classified into three categories, namely; membrane, electrochemical and adsorptive techniques. Reverse osmosis, nanofiltration and electrodialysis membrane techniques are reviewed. The electrochemical techniques discussed are electrolysis, capacitive deionization and membrane capacitive deionization. Studies on bromide and iodide removal using adsorptive techniques including; layered double hydroxides, impregnated activated carbons, carbon aerogels, ion exchange resins, aluminium coagulation and soils are also assessed. Halide removal techniques have been compared, and areas for future research have been identified. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Preparation and optical characteristics of layered perovskite-type lead-bromide-incorporated azobenzene chromophores

    NASA Astrophysics Data System (ADS)

    Sasai, Ryo; Shinomura, Hisashi

    2013-02-01

    Lead bromide-based layered perovskite powders with azobenzene derivatives were prepared by a homogeneous precipitation method. From the diffuse reflectance (DR) and photoluminescence (PL) spectra of the hybrid powder materials, the present hybrids exhibited sharp absorption and PL peaks originating from excitons produced in the PbBr42- layer. When the present hybrid powder was irradiated with UV light at 350 nm, the absorption band from the trans-azobenzene chromophore, observed around 350 nm, decreased, while the absorption band from the cis-azobenzene chromophore, observed around 450 nm, increased. These results indicate that azobenzene chromophores in the present hybrid materials exhibit reversible photoisomerization. Moreover, it was found that the PL intensity from the exciton also varied due to photoisomerization of the azobenzene chromophores in the present hybrid. Thus, for the first time we succeeded in preparing the azobenzene derivative lead-bromide-based layered perovskite with photochromism before and after UV light irradiation.

  4. Formation of NDMA and halogenated DBPs by chloramination of tertiary amines: the influence of bromide ion.

    PubMed

    Le Roux, Julien; Gallard, Hervé; Croué, Jean-Philippe

    2012-02-07

    The formation of NDMA and other DBPs (including THMs, HANs, and HKs) has been investigated by chloramination of several tertiary amines in the absence and presence of bromide ion. NDMA formation from the most reactive tertiary amines (e.g., dimethylaminomethylfurfuryl alcohol or DMP30) was enhanced in the presence of bromide due to the formation of brominated oxidant species such as bromochloramine (NHBrCl) and the hypothetical UDMH-Br as an intermediate. The formation of NDMA by chloramination of less reactive model compounds was inhibited in the presence of bromide. This can be explained by competitive reactions leading to the production of brominated DBPs (i.e., THMs). In the presence of bromide, the formation of brominated THMs during chloramination can be attributed to the presence of small amounts of HOBr produced by the decomposition of chloramines and bromamines. The results are of particular interest to understand NDMA formation mechanisms, especially during chloramination of wastewaters impacted by anthropogenic tertiary amines and containing bromide ion.

  5. Detection and control of Fusarium oxysporum and Cylindrocarpon destructans in forest nursery soils

    Treesearch

    Catherine Crosby; Lynne Carpenter-Boggs; Stewart Higgins; Nabil Khadduri

    2010-01-01

    Fusarium oxysporum and Cylindrocarpon destructans cause root disease that leads to significant crop losses in forest nurseries when not treated. Treatment currently relies on methyl bromide fumigation to eradicate soil pathogens. New environmental protection laws, however, are phasing out methyl bromide. Alternative chemical treatments are being tested, as well as...

  6. Reactive films for mitigating methyl bromide emissions from fumigated soil

    USDA-ARS?s Scientific Manuscript database

    Emissions of methyl bromide (MeBr) from agricultural fumigation can lead to depletion of the stratospheric ozone layer, and so its use is being phased out. However, as MeBr is still widely used under Critical Use Exemptions, strategies are still required to control such emissions. In this work, nove...

  7. Preparation and optical characteristics of layered perovskite-type lead-bromide-incorporated azobenzene chromophores

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sasai, Ryo, E-mail: rsasai@riko.shimane-u.ac.jp; Shinomura, Hisashi

    Lead bromide-based layered perovskite powders with azobenzene derivatives were prepared by a homogeneous precipitation method. From the diffuse reflectance (DR) and photoluminescence (PL) spectra of the hybrid powder materials, the present hybrids exhibited sharp absorption and PL peaks originating from excitons produced in the PbBr{sub 4}{sup 2-} layer. When the present hybrid powder was irradiated with UV light at 350 nm, the absorption band from the trans-azobenzene chromophore, observed around 350 nm, decreased, while the absorption band from the cis-azobenzene chromophore, observed around 450 nm, increased. These results indicate that azobenzene chromophores in the present hybrid materials exhibit reversible photoisomerization.more » Moreover, it was found that the PL intensity from the exciton also varied due to photoisomerization of the azobenzene chromophores in the present hybrid. Thus, for the first time we succeeded in preparing the azobenzene derivative lead-bromide-based layered perovskite with photochromism before and after UV light irradiation. - Graphical abstract: For the first time, we succeeded in preparing the azobenzene derivative lead-bromide-based layered perovskite with photochromism before and after UV light irradiation. Highlights: Black-Right-Pointing-Pointer PbBr-based layered perovskite with azobenezene derivatives could be synthesized by a homogeneous precipitation method. Black-Right-Pointing-Pointer Azobenzene derivatives incorporated the present hybrid that exhibited reversible photoisomerization under UV and/or visible light irradiation. Black-Right-Pointing-Pointer PL property of the present hybrid could also be varied by photoisomerization.« less

  8. Sodium bromide additive improved film morphology and performance in perovskite light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Li, Jinghai; Cai, Feilong; Yang, Liyan; Ye, Fanghao; Zhang, Jinghui; Gurney, Robert S.; Liu, Dan; Wang, Tao

    2017-07-01

    Organometal halide perovskite is a promising material to fabricate light-emitting diodes (LEDs) via solution processing due to its exceptional optoelectronic properties. However, incomplete precursor conversion and various defect states in the perovskite light-emitting layer lead to low luminance and external quantum efficiency of perovskite LEDs. We show here the addition of an optimum amount of sodium bromide in the methylammonium lead bromide (MAPbBr3) precursor during a one-step perovskite solution casting process can effectively improve the film coverage, enhance the crystallinity, and passivate ionic defects on the surface of MAPbBr3 crystal grains, resulting in LEDs with a reduced turn-on voltage from 2.8 to 2.3 V and an enhanced maximum luminance from 1059 to 6942 Cd/m2 when comparing with the pristine perovskite-based device.

  9. Reversible air-induced optical and electrical modulation of methylammonium lead bromide (MAPbBr3) single crystals

    NASA Astrophysics Data System (ADS)

    Zhang, Huotian; Liu, Yiting; Lu, Haizhou; Deng, Wan; Yang, Kang; Deng, Zunyi; Zhang, Xingmin; Yuan, Sijian; Wang, Jiao; Niu, Jiaxin; Zhang, Xiaolei; Jin, Qingyuan; Feng, Hongjian; Zhan, Yiqiang; Zheng, Lirong

    2017-09-01

    The photoluminescence (PL) variations of organic-inorganic hybrid lead halide perovskites in different atmospheres are well documented, while the fundamental mechanism still lacks comprehensive understandings. This study reports the reversible optical and electrical properties of methylammonium lead bromide (MAPbBr3 or CH3NH3PbBr3) single crystals caused by air infiltration. With the change in the surrounding atmosphere from air to vacuum, the PL intensity of perovskite single crystals decreases, while the conductivity increases. By means of first-principles computational studies, the shallow trap states are considered as key elements in PL and conductivity changes. These results have important implications for the characterization and application of organic-inorganic hybrid lead halide perovskites in vacuum.

  10. MAPbI2.9-xBrxCl0.1 hybrid halide perovskites: Shedding light on the effect of chloride and bromide ions on structural and photoluminescence properties

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

    The optical and structural properties of CH3NH3PbI3 can be adjusted by introducing other extrinsic ions such as chloride and bromide. In this work, mixed bromide iodide lead perovskites with a 10% fraction of chloride were prepared from methylamine, lead nitrate and the corresponding hydro acid (X = I, Br, Cl). The effect of bromide and chloride incorporation on different properties of perovskite thin film was investigated. The Pawley fit method indicates the formation of the iodide halide MAPbI3 Pm-3 m cubic phase for x = 0 and the tetragonal P4/mmm phase for x ≥ 0.3. All deposited films showed a strong absorbance in the UV-vis range. The band gap values were estimated from absorbance measurements. It was found that the onset of the absorption edge for MAPbI2.9-xBrxCl0.1 thin film perovskites ranges between 1.60 and 1.80 eV. Moreover, it was found that both Cl and Br affect the PL emission of the mixed halide lead perovskite, the MAPbI2.9-xBrxCl0.1 films displayed intermediate values from 730 nm (MAPbI2.2Br0.7Cl0.1) to 770 nm (MAPbI2.6Br0.3Cl0.1).

  11. High spectral resolution of gamma-rays at room temperature by perovskite CsPbBr 3 single crystals

    DOE PAGES

    He, Yihui; Matei, Liviu; Jung, Hee Joon; ...

    2018-04-23

    Gamma-ray detection and spectroscopy is the quantitative determination of their energy spectra, and is of critical value and critically important in diverse technological and scientific fields. Here we report an improved melt growth method for cesium lead bromide and a special detector design with asymmetrical metal electrode configuration that leads to a high performance at room temperature. As-grown centimeter-sized crystals possess extremely low impurity levels (below 10 p.p.m. for total 69 elements) and detectors achieve 3.9% energy resolution for 122 keV 57Co gamma-ray and 3.8% for 662 keV 137Cs gamma-ray. Cesium lead bromide is unique among all gamma-ray detection materialsmore » in that its hole transport properties are responsible for the high performance. The superior mobility-lifetime product for holes (1.34 × 10 –3 cm 2 V –1) derives mainly from the record long hole carrier lifetime (over 25 μs). Here, the easily scalable crystal growth and high-energy resolution, highlight cesium lead bromide as an exceptional next generation material for room temperature radiation detection.« less

  12. High spectral resolution of gamma-rays at room temperature by perovskite CsPbBr 3 single crystals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    He, Yihui; Matei, Liviu; Jung, Hee Joon

    Gamma-ray detection and spectroscopy is the quantitative determination of their energy spectra, and is of critical value and critically important in diverse technological and scientific fields. Here we report an improved melt growth method for cesium lead bromide and a special detector design with asymmetrical metal electrode configuration that leads to a high performance at room temperature. As-grown centimeter-sized crystals possess extremely low impurity levels (below 10 p.p.m. for total 69 elements) and detectors achieve 3.9% energy resolution for 122 keV 57Co gamma-ray and 3.8% for 662 keV 137Cs gamma-ray. Cesium lead bromide is unique among all gamma-ray detection materialsmore » in that its hole transport properties are responsible for the high performance. The superior mobility-lifetime product for holes (1.34 × 10 –3 cm 2 V –1) derives mainly from the record long hole carrier lifetime (over 25 μs). Here, the easily scalable crystal growth and high-energy resolution, highlight cesium lead bromide as an exceptional next generation material for room temperature radiation detection.« less

  13. Phase behavior of gemini surfactant hexylene-1,6-bis(dodecyldimethylammonium bromide) and polyelectrolyte NaPAA.

    PubMed

    Pi, Yingying; Shang, Yazhuo; Peng, Changjun; Liu, Honglai; Hu, Ying; Jiang, Jianwen

    2006-07-01

    The phase behavior of aqueous mixtures of gemini surfactant hexylene-1,6-bis(dodecyldimethylammonium bromide) (12-6-12) and oppositely charged polyelectrolyte sodium polyacrylate (NaPAA) has been studied experimentally. Compared to the mixtures of the traditional surfactant dodecyltrimethylammonium bromide (DTAB) and NaPAA, the gel phase region in the 12-6-12/NaPAA solution is larger. Element analysis reveals that NaPAA in the gel phase tends to replace the counterions of surfactant micelle and to release its own counterions. Spherical aggregates are observed in either top or bottom gel phase as detected by transmission electron microscopy. The addition of sodium bromide (NaBr) leads to a decrease in the gel phase region and the occurrence of a new cream phase.

  14. Laboratory Evaluation of Drop-in Solvent Alternatives to n-Propyl Bromide for Vapor Degreasing

    NASA Technical Reports Server (NTRS)

    Mitchell, Mark A.; Lowrey, Nikki M.

    2012-01-01

    Based on this limited laboratory study, solvent blends of trans-1,2 dichloroethylene with HFEs, HFCs, or PFCs appear to be viable alternatives to n-propyl bromide for vapor degreasing. The lower boiling points of these blends may lead to greater solvent loss during use. Additional factors must be considered when selecting a solvent substitute, including stability over time, VOC, GWP, toxicity, and business considerations.

  15. Test report : Raytheon / KTech RK30 Energy Storage System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rose, David Martin; Schenkman, Benjamin L.; Borneo, Daniel R.

    2013-10-01

    The Department of Energy Office of Electricity (DOE/OE), Sandia National Laboratories (SNL) and the Base Camp Integration Lab (BCIL) partnered together to incorporate an energy storage system into a microgrid configured Forward Operating Base to reduce the fossil fuel consumption and to ultimately save lives. Energy storage vendors will be sending their systems to SNL Energy Storage Test Pad (ESTP) for functional testing and then to the BCIL for performance evaluation. The technologies that will be tested are electro-chemical energy storage systems comprising of lead acid, lithium-ion or zinc-bromide. Raytheon/KTech has developed an energy storage system that utilizes zinc-bromide flowmore » batteries to save fuel on a military microgrid. This report contains the testing results and some limited analysis of performance of the Raytheon/KTech Zinc-Bromide Energy Storage System.« less

  16. One-dimensional organic lead halide perovskites with efficient bluish white-light emission

    NASA Astrophysics Data System (ADS)

    Yuan, Zhao; Zhou, Chenkun; Tian, Yu; Shu, Yu; Messier, Joshua; Wang, Jamie C.; van de Burgt, Lambertus J.; Kountouriotis, Konstantinos; Xin, Yan; Holt, Ethan; Schanze, Kirk; Clark, Ronald; Siegrist, Theo; Ma, Biwu

    2017-01-01

    Organic-inorganic hybrid metal halide perovskites, an emerging class of solution processable photoactive materials, welcome a new member with a one-dimensional structure. Herein we report the synthesis, crystal structure and photophysical properties of one-dimensional organic lead bromide perovskites, C4N2H14PbBr4, in which the edge sharing octahedral lead bromide chains [PbBr4 2-]∞ are surrounded by the organic cations C4N2H14 2+ to form the bulk assembly of core-shell quantum wires. This unique one-dimensional structure enables strong quantum confinement with the formation of self-trapped excited states that give efficient bluish white-light emissions with photoluminescence quantum efficiencies of approximately 20% for the bulk single crystals and 12% for the microscale crystals. This work verifies once again that one-dimensional systems are favourable for exciton self-trapping to produce highly efficient below-gap broadband luminescence, and opens up a new route towards superior light emitters based on bulk quantum materials.

  17. One-dimensional organic lead halide perovskites with efficient bluish white-light emission

    PubMed Central

    Yuan, Zhao; Zhou, Chenkun; Tian, Yu; Shu, Yu; Messier, Joshua; Wang, Jamie C.; van de Burgt, Lambertus J.; Kountouriotis, Konstantinos; Xin, Yan; Holt, Ethan; Schanze, Kirk; Clark, Ronald; Siegrist, Theo; Ma, Biwu

    2017-01-01

    Organic-inorganic hybrid metal halide perovskites, an emerging class of solution processable photoactive materials, welcome a new member with a one-dimensional structure. Herein we report the synthesis, crystal structure and photophysical properties of one-dimensional organic lead bromide perovskites, C4N2H14PbBr4, in which the edge sharing octahedral lead bromide chains [PbBr4 2−]∞ are surrounded by the organic cations C4N2H14 2+ to form the bulk assembly of core-shell quantum wires. This unique one-dimensional structure enables strong quantum confinement with the formation of self-trapped excited states that give efficient bluish white-light emissions with photoluminescence quantum efficiencies of approximately 20% for the bulk single crystals and 12% for the microscale crystals. This work verifies once again that one-dimensional systems are favourable for exciton self-trapping to produce highly efficient below-gap broadband luminescence, and opens up a new route towards superior light emitters based on bulk quantum materials. PMID:28051092

  18. One-dimensional organic lead halide perovskites with efficient bluish white-light emission.

    PubMed

    Yuan, Zhao; Zhou, Chenkun; Tian, Yu; Shu, Yu; Messier, Joshua; Wang, Jamie C; van de Burgt, Lambertus J; Kountouriotis, Konstantinos; Xin, Yan; Holt, Ethan; Schanze, Kirk; Clark, Ronald; Siegrist, Theo; Ma, Biwu

    2017-01-04

    Organic-inorganic hybrid metal halide perovskites, an emerging class of solution processable photoactive materials, welcome a new member with a one-dimensional structure. Herein we report the synthesis, crystal structure and photophysical properties of one-dimensional organic lead bromide perovskites, C 4 N 2 H 14 PbBr 4 , in which the edge sharing octahedral lead bromide chains [PbBr 4   2- ] ∞ are surrounded by the organic cations C 4 N 2 H 14   2+ to form the bulk assembly of core-shell quantum wires. This unique one-dimensional structure enables strong quantum confinement with the formation of self-trapped excited states that give efficient bluish white-light emissions with photoluminescence quantum efficiencies of approximately 20% for the bulk single crystals and 12% for the microscale crystals. This work verifies once again that one-dimensional systems are favourable for exciton self-trapping to produce highly efficient below-gap broadband luminescence, and opens up a new route towards superior light emitters based on bulk quantum materials.

  19. Emission characteristics of plasma based on xenon-rubidium bromide mixture

    NASA Astrophysics Data System (ADS)

    Heneral, A. A.; Avtaeva, S. V.

    2017-10-01

    Luminescence spectra of a longitudinal pulse-periodic discharge in xenon mixture with rubidium bromide vapors (Xe-RbBr) are studied experimentally at low pressures. The conditions leading to the appearance of intense bands of ultraviolet radiation of exciplex XeBr* molecules in the spectral interval between 200 and 400 nm are found. The highest yield of UV radiation of XeBr* molecules is achieved when the temperature of discharge-tube walls is equal to 750°C. A maximum power of UV radiation from the entire plasma volume as high as 4.8 W is obtained.

  20. Copper(II)-catalyzed amidations of alkynyl bromides as a general synthesis of ynamides and Z-enamides. An intramolecular amidation for the synthesis of macrocyclic ynamides.

    PubMed

    Zhang, Xuejun; Zhang, Yanshi; Huang, Jian; Hsung, Richard P; Kurtz, Kimberly C M; Oppenheimer, Jossian; Petersen, Matthew E; Sagamanova, Irina K; Shen, Lichun; Tracey, Michael R

    2006-05-26

    A general and efficient method for the coupling of a wide range of amides with alkynyl bromides is described here. This novel amidation reaction involves a catalytic protocol using copper(II) sulfate-pentahydrate and 1,10-phenanthroline to direct the sp-C-N bond formation, leading to a structurally diverse array of ynamides including macrocyclic ynamides via an intramolecular amidation. Given the surging interest in ynamide chemistry, this atom economical synthesis of ynamides should invoke further attention from the synthetic organic community.

  1. Direct Observation of Halide Migration and its Effect on the Photoluminescence of Methylammonium Lead Bromide Perovskite Single Crystals.

    PubMed

    Luo, Yanqi; Khoram, Parisa; Brittman, Sarah; Zhu, Zhuoying; Lai, Barry; Ong, Shyue Ping; Garnett, Erik C; Fenning, David P

    2017-11-01

    Optoelectronic devices based on hybrid perovskites have demonstrated outstanding performance within a few years of intense study. However, commercialization of these devices requires barriers to their development to be overcome, such as their chemical instability under operating conditions. To investigate this instability and its consequences, the electric field applied to single crystals of methylammonium lead bromide (CH 3 NH 3 PbBr 3 ) is varied, and changes are mapped in both their elemental composition and photoluminescence. Synchrotron-based nanoprobe X-ray fluorescence (nano-XRF) with 250 nm resolution reveals quasi-reversible field-assisted halide migration, with corresponding changes in photoluminescence. It is observed that higher local bromide concentration is correlated to superior optoelectronic performance in CH 3 NH 3 PbBr 3 . A lower limit on the electromigration rate is calculated from these experiments and the motion is interpreted as vacancy-mediated migration based on nudged elastic band density functional theory (DFT) simulations. The XRF mapping data provide direct evidence of field-assisted ionic migration in a model hybrid-perovskite thin single crystal, while the link with photoluminescence proves that the halide stoichiometry plays a key role in the optoelectronic properties of the perovskite. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Designing solid-liquid interphases for sodium batteries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Choudhury, Snehashis; Wei, Shuya; Ozhabes, Yalcin

    Secondary batteries based on earth-abundant sodium metal anodes are desirable for both stationary and portable electrical energy storage. Room-temperature sodium metal batteries are impractical today because morphological instability during recharge drives rough, dendritic electrodeposition. Chemical instability of liquid electrolytes also leads to premature cell failure as a result of parasitic reactions with the anode. Here we use joint density-functional theoretical analysis to show that the surface diffusion barrier for sodium ion transport is a sensitive function of the chemistry of solid–electrolyte interphase. In particular, we find that a sodium bromide interphase presents an exceptionally low energy barrier to ion transport,more » comparable to that of metallic magnesium. We evaluate this prediction by means of electrochemical measurements and direct visualization studies. These experiments reveal an approximately three-fold reduction in activation energy for ion transport at a sodium bromide interphase. Direct visualization of sodium electrodeposition confirms large improvements in stability of sodium deposition at sodium bromide-rich interphases.« less

  3. Designing solid-liquid interphases for sodium batteries

    DOE PAGES

    Choudhury, Snehashis; Wei, Shuya; Ozhabes, Yalcin; ...

    2017-10-12

    Secondary batteries based on earth-abundant sodium metal anodes are desirable for both stationary and portable electrical energy storage. Room-temperature sodium metal batteries are impractical today because morphological instability during recharge drives rough, dendritic electrodeposition. Chemical instability of liquid electrolytes also leads to premature cell failure as a result of parasitic reactions with the anode. Here we use joint density-functional theoretical analysis to show that the surface diffusion barrier for sodium ion transport is a sensitive function of the chemistry of solid–electrolyte interphase. In particular, we find that a sodium bromide interphase presents an exceptionally low energy barrier to ion transport,more » comparable to that of metallic magnesium. We evaluate this prediction by means of electrochemical measurements and direct visualization studies. These experiments reveal an approximately three-fold reduction in activation energy for ion transport at a sodium bromide interphase. Direct visualization of sodium electrodeposition confirms large improvements in stability of sodium deposition at sodium bromide-rich interphases.« less

  4. Interaction of pyridostigmine bromide and N,N-diethyl-m-toluamide alone and in combination with P-glycoprotein expressed in Escherichia coli leaky mutant.

    PubMed

    El-Masry, Eman M; Abou-Donia, Mohamed B

    2006-05-01

    P-glycoprotein (P-gp), the most extensively studied ATP-binding transporter, functions as a biological barrier by extruding toxic substances and xenobiotics out of the cell. This study was carried out to determine the effect of N,N-diethyl-m-toluamide (DEET) and pyridostigmine bromide (PB), alone and in combination, on P-gp expression using Escherichia coli leaky mutant transformed with Mdr1 gene (pT5-7/mdr1), which codes for P-gp or lactose permease (pT5-7/lacY) as negative control. Also, daunomycin (a known P-gp sustrate) was used as a positive control and reserpine (a known P-gp inhibitor) served as a negative control. An in vitro cell-resistant assay was used to monitor the potential of test compounds to interact with P-gp. Following exposure of the cells to pyridostigmine bromide or daunomycin, P-gp conferred significant resistance against both compounds, while reserpine and DEET significantly inhibited the glycoprotein. Cells were grown in the presence of noncytotoxic concentrations of daunomycin, pyridostigmine bromide, reserpine, or DEET, and membrane fractions were examined by Western immunoblotting for expression of P-gp. Daunomycin induced P-gp expression quantitatively more than pyridostigmine bromide, while reserpine and DEET significantly inhibited P-gp expression in cells harboring mdr1. Photoaffinity labeling experiment performed with the P-gp ligand [125I]iodoarylazidoprazosin demonstrated that compounds that induced or inhibited P-gp transport activity also bound to P-gp. DEET was also found to be a potent inhibitor of P-gp-mediated ATPase activity, whereas pyridostigmine bromide increased P-gp ATPase activity. Cells expressing P-gp or lac permease were exposed to pyridostigmine bromide and DEET, alone and in combination. Noncytotoxic concentrations of DEET significantly inhibited P-gp-mediated resistance against pyridostigmine bromide, resulting in a reduction of the number of effective drug interactions with biological targets. An explanation of these results might be that DEET is a third-generation inhibitor of P-gp; it has high potency and specificity for P-gp, it inhibits hydrolysis of ATP, it exerts no appreciable impact on cytochrome P-450 3A4, and it prevents transport of xenobiotics, such as pyridostigmine bromide, out of the cell. This conclusion explains, at least in part, the increased toxicity and bioavailability of pyridostigmine bromide following combined administration with DEET. This study improves our understanding of the basis of chemical interactions with DEET by defining the ability of drugs to interact with P-gp either as inhibitors or substrates, which may in turn lead to altered efficacy or toxicity.

  5. A spectrophotometric study of aqueous Au(III) halide-hydroxide complexes at 25-80 °C

    NASA Astrophysics Data System (ADS)

    Usher, Al; McPhail, D. C.; Brugger, Joël

    2009-06-01

    The mobility and transport of gold in low-temperature waters and brines is affected by the aqueous speciation of gold, which is sensitive in particular to pH, oxidation and halide concentrations. In this study, we use UV-Vis spectrophotometry to identify and measure the thermodynamic properties of Au(III) aqueous complexes with chloride, bromide and hydroxide. Au(III) forms stable square planar complexes with hydroxide and halide ligands. Based on systematic changes in the absorption spectra of solutions in three binary systems NaCl-NaBr, NaCl-NaOH and NaBr-NaOH at 25 °C, we derived log dissociation constants for the following mixed and end-member halide and hydroxide complexes: [AuCl 3Br] -, [AuCl 2Br 2] -, [AuBr 3Cl] - and [AuBr 4] -; [AuCl 3(OH)] -, [AuCl 2(OH) 2] -, [AuCl(OH) 3] - and [Au(OH) 4] -; and [AuBr 3(OH)] -, [AuBr 2(OH) 2] - and [AuBr(OH) 3] -. These are the first reported results for the mixed chloride-bromide complexes. Increasing temperature to 80 °C resulted in an increase in the stability of the mixed chloride-bromide complexes, relative to the end-member chloride and bromide complexes. For the [AuCl (4-n)(OH) n] - series of complexes ( n = 0-4), there is an excellent agreement between our spectrophotometric results and previous electrochemical results of Chateau et al. [Chateau et al. (1966)]. In other experiments, the iodide ion (I -) was found to be unstable in the presence of Au(III), oxidizing rapidly to I 2(g) and causing Au to precipitate. Predicted Au(III) speciation indicates that Au(III) chloride-bromide complexes can be important in transporting gold in brines with high bromide-chloride ratios (e.g., >0.05), under oxidizing (atmospheric), acidic (pH < 5) conditions. Native gold solubility under atmospheric oxygen conditions is predicted to increase with decreasing pH in acidic conditions, increasing pH in alkaline conditions, increasing chloride, especially at acid pH, and increasing bromide for bromide/chloride ratios greater than 0.05. The results of our study increase the understanding of gold aqueous geochemistry, with the potential to lead to new methods for mineral exploration, hydrometallurgy and medicine.

  6. Flexible shielding system for radiation protection

    NASA Technical Reports Server (NTRS)

    Babin, A.

    1972-01-01

    Modular construction of low cost flexible radiation shielding panels consists of water filled steels cans, zinc bromide windows, turntable unit, master-slave manipulators, and interlocking lead bricks. Easy modifications of shielding wall thicknesses are obtained by rearranging overall geometry of portable components.

  7. Residues after fumigation with methyl bromide: bromide ion and methyl bromide in middlings and final cereal foodstuffs.

    PubMed

    Cova, D; Molinari, G P; Rossini, L

    1986-01-01

    Methyl bromide and bromide ion concentrations were estimated in pasta manufactured before and after fumigation with methyl bromide. The first trial estimated the bromide ion concentrations in fumigated and unfumigated flours and in pastas obtained from these. The concentration of bromide ions in fumigated flours was not significantly different from unfumigated flours. Only some pastas, manufactured from fumigated flours, showed a higher bromide ion concentration than those manufactured from unfumigated flours. The second trial evaluated the bromide ion concentrations of rices, white flours, flours, pastas made only from flours, pastas with eggs and pastas with eggs and spinach, before and after exposure to methyl bromide in their retail packagings. The bromide ion concentrations in fumigated pastas with eggs, pastas with eggs and spinach and rice were higher than in those unfumigated. In the pastas with eggs the bromide ion concentration after fumigation increased ten times (from about 4 to 40 mg/kg). Results showed that the bromide ion and methyl bromide levels estimated in all the foodstuffs examined were lower than the maximum limits fixed by several different national regulations.

  8. 49 CFR 173.193 - Bromoacetone, methyl bromide, chloropicrin and methyl bromide or methyl chloride mixtures, etc.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... methyl bromide or methyl chloride mixtures, etc. 173.193 Section 173.193 Transportation Other Regulations... bromide, chloropicrin and methyl bromide or methyl chloride mixtures, etc. (a) Bromoacetone must be...) Bromoacetone, methyl bromide, chloropicrin and methyl bromide mixtures, chloropicrin and methyl chloride...

  9. Single crystal growth and surface chemical stability of KPb2Br5

    NASA Astrophysics Data System (ADS)

    Atuchin, V. V.; Isaenko, L. I.; Kesler, V. G.; Tarasova, A. Yu.

    2011-03-01

    Single crystal of KPb2Br5 has been grown using the Bridgman technique. Initially the synthesis of stoichiometric KPb2Br5 compound was performed from high purity bromide salts. Electronic structure of KPb2Br5 has been determined with X-ray photoelectron spectroscopy for powdered sample fabricated by grinding in air. Drastic chemical interaction of KPb2Br5 with atmosphere has not been detected. Chemical bonding in potassium- and lead-containing bromides is considered using binding energy differences ΔK=(BE K 2p3/2-BE Br 3d) and ΔPb=(BE Pb 4f7/2-BE Br 3d), respectively, as representative parameters.

  10. Manganese-Doped One-Dimensional Organic Lead Bromide Perovskites with Bright White Emissions.

    PubMed

    Zhou, Chenkun; Tian, Yu; Khabou, Oussama; Worku, Michael; Zhou, Yan; Hurley, Joseph; Lin, Haoran; Ma, Biwu

    2017-11-22

    Single-component white-emitting phosphors are highly promising to simplify the fabrication of optically pumped white light-emitting diodes. To achieve white emission, precise control of the excited state dynamics is required for a single-component system to generate emissions with different energies in the steady state. Here, we report a new class of white phosphors based on manganese (Mn)-doped one-dimensional (1D) organic lead bromide perovskites. The bright white emission is the combination of broadband blue emission from the self-trapped excited states of the 1D perovskites and red emission from the doped Mn 2+ ions. Because of the indirect nature of the self-trapped excited states in 1D perovskites, there is no energy transfer from these states to the Mn 2+ ions, resulting in an efficient dual emission. As compared to the pristine 1D perovskites with bluish-white emission, these Mn-doped 1D perovskites exhibit much higher color rendering index of up to 87 and photoluminescence quantum efficiency of up to 28%.

  11. Fluoride-containing podophyllum derivatives exhibit antitumor activities through enhancing mitochondrial apoptosis pathway by increasing the expression of caspase-9 in HeLa cells

    PubMed Central

    Zhao, Wei; Yang, Yong; Zhang, Ya-Xuan; Zhou, Chen; Li, Hong-Mei; Tang, Ya-Ling; Liang, Xin-Hua; Chen, Tao; Tang, Ya-Jie

    2015-01-01

    This work aims to provide sampling of halogen-containing aniline podophyllum derivatives and their mode of action with an in-depth comparison among fluorine, chloride and bromide for clarifying the important role and impact of fluorine substitution on enhancing antitumor activity, with an emphasis on the development of drug rational design for antitumor drug. The tumor cytotoxicity of fluoride-containing aniline podophyllum derivatives were in general improved by 10–100 times than those of the chloride and bromide-containing aniline podophyllum derivatives since fluoride could not only strongly solvated in protic solvents but also forms tight ion pairs in most aprotic solvents. When compared with chloride and bromide, the higher electronegativity fluoride substituted derivatives significantly enhanced mitochondrial apoptosis pathway by remarkably increasing the expression of caspase-9 in HeLa cells. The current findings would stimulate an enormous amount of research directed toward exploiting novel leading compounds based on podophyllum derivatives, especially for the fluoride-substituted structures with promising antitumor activity. PMID:26608216

  12. Effects of Nonhydrostatic Stress on Structural and Optoelectronic Properties of Methylammonium Lead Bromide Perovskite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Rong; Cai, Weizhao; Bi, Tiange

    We report synchrotron X-ray diffraction, photoconductivity, and photoluminescence investigations of methylammonium-lead-bromide (MAPbBr3) under various stress conditions, supported by density-functional-theory (DFT) calculations. The properties of MAPbBr3 show substantial dependence on the hydrostatic conditions. While nonhydrostatic compression of MAPbBr3 leads to amorphization above 2.4 GPa, under quasi-hydrostatic (Ar) and hydrostatic (He) pressure, the sample remains in crystalline phases. A sequence of phase transitions between two cubic phases and orthorhombic Pnma phase is observed when using Ar, or no pressure-transmitting-medium (PTM). In helium-PTM only transitions between the two cubic structures and a new isostructural phase transition with a large volume collapse to amore » third cubic-phase at 2.7 GPa was observed. The photoluminescence measurements indicate a pressure-induced band gap-narrowing in the cubic phase I, and a blue-shift in the orthorhombic structure. DFT calculations illustrate that the dynamics of the organic molecules and the inorganic lattice, coupled via the N–H···Br hydrogen-bonding interactions, affect the Pb–Br distance and the bandgap evolution under pressure.« less

  13. Cetyltrimethyl Ammonium Bromide as Corrosion Inhibitor for Zinc Used in Hydrochloric Acid

    NASA Astrophysics Data System (ADS)

    Sun, C. X.; Du, J. J.; Ma, Z. W.; Huang, C. S.; Wu, J. Y.

    2018-05-01

    A compound inhibitor composed of cetyltrimethyl ammonium bromide (CTAB) and bromohexadecyl pyridine was tested as corrosion inhibitor for zinc in hydrochloric acid. The results of static coupon test show that the compound inhibitor can effectively protect zinc from corrosion and the best concentration ratio is CTAB 50 mg/L and bromohexadecyl pyridine 200 mg/L. The polarization results show that the compound inhibitor will cause a negative shift of E0 of zinc in hydrochloric acid. The EIS (electrchemical impedance spectra) results show that the inhibitor leads to a bigger radius and has one time constant. SEM results show that the CTAB and bromohexadecyl pyridine form a uniform and compact membrane on the surface of zinc that can protect zinc from corroding effectively.

  14. Additive-mediated electrochemical synthesis of platelike copper crystals for methanol electrooxidation.

    PubMed

    Venkatasubramanian, Rajesh; He, Jibao; Johnson, Michael W; Stern, Ilan; Kim, Dae Ho; Pesika, Noshir S

    2013-10-29

    A room-temperature electrochemical approach to synthesizing anisotropic platelike copper microcrystals and nanocrystals in the presence of potassium bromide is presented. Morphological and elemental characterization was performed using SEM, TEM, and XRD to confirm the anisotropic morphology and crystal structure of the synthesized copper particles. A possible mechanism for explaining the anisotropic crystal growth is proposed on the basis of the preferential adsorption of bromide ions to selective crystal faces. The shape-dependent electrocatalytic property of copper particles is demonstrated by its enhanced catalytic activity for methanol oxidation. Further development of such anisotropic copper particles localized on an electrode surface will lead us to find a suitable alternative for noble metal-based electrocatalysts for the methanol oxidation reaction relevant to fuel cells.

  15. 77 FR 20752 - Methyl Bromide; Proposed Pesticide Tolerance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... fumigated with methyl bromide requires a tolerance. Without a tolerance or exemption, food or feed... livestock feeding items resulting from fumigation of cottonseed with methyl bromide are covered by existing... produced from cottonseed fumigated with methyl bromide would not contain residues of methyl bromide...

  16. 40 CFR 180.123 - Inorganic bromide residues resulting from fumigation with methyl bromide; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... from fumigation with methyl bromide; tolerances for residues. 180.123 Section 180.123 Protection of... fumigation with methyl bromide; tolerances for residues. (a) General. (1) Tolerances are established for... on dog food, resulting from fumigation with methyl bromide. (ii) 125 parts per million for residues...

  17. 40 CFR 180.123 - Inorganic bromide residues resulting from fumigation with methyl bromide; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... from fumigation with methyl bromide; tolerances for residues. 180.123 Section 180.123 Protection of... fumigation with methyl bromide; tolerances for residues. (a) General. (1) Tolerances are established for... result of fumigation of the processed food with methyl bromide or from such fumigation in addition to the...

  18. A practical comparison of Copper Bromide Laser for the treatment of vascular lesions.

    PubMed

    Lee, SunWoo; Lee, TaeBum; Kim, HoYoun; Kim, JungSoo; Eun, HyeJun; Kim, RyunKyung

    2013-01-01

    The recent rapid growth in demand for aesthetic non-invasive laser treatments such as unwanted skin rejuvenation, removal of age-related vascular blemishes has led to a boom in the medical devices to treat these conditions. Among diverse laser for skin treatment, copper bromide laser is a very effective, safe, and well tolerated treatment for facial telangiectasia at various energy levels and the most important thing of the copper bromide laser device is that the stability of the energy. However there is no evidence about effective copper bromide laser's energy level for the treatment of vascular lesions. We compared energy stability and treatment performance between two energy levels in 2 W and 8 W which commonly use in laser treatment for the vascular lesions. 8 W copper bromide laser was more stable compared than 2 W copper bromide laser. Also, 8 W copper bromide laser was effectively superior to 2 W copper bromide laser in treatment of vascular legion. Consequently, 8 W copper bromide laser treatment for vascular lesion might be more suitable than 2 W copper bromide laser.

  19. Thallium Bromide Deposited Using Spray Coating

    NASA Astrophysics Data System (ADS)

    Ferreira, E. S.; Mulato, M.

    2012-08-01

    Spray coating was used to produce thallium bromide samples on glass substrates. The influence of several fabrication parameters on the final structural properties of the samples was investigated. Substrate position, substrate temperature, solution concentration, carrying gas, and solution flow were varied systematically, the physical deposition mechanism involved in each case being discussed. Total deposition time of about 3.5 h can lead to 62-μm-thick films, comprising completely packed micrometer-sized crystalline grains. X-ray diffraction and scanning electron microscopy were used to characterize the samples. On the basis of the experimental data, the optimum fabrication conditions were identified. The technique offers an alternative method for fast, cheap fabrication of large-area devices for the detection of high-energy radiation, i.e., X-rays and γ-rays, in medical imaging.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rose, David Martin; Schenkman, Benjamin L.; Borneo, Daniel R.

    The Department of Energy Office of Electricity (DOE/OE), Sandia National Laboratories (SNL) and the Base Camp Integration Lab (BCIL) partnered together to incorporate an energy storage system into a microgrid configured Forward Operating Base to reduce the fossil fuel consumption and to ultimately save lives. Energy storage vendors will be sending their systems to SNL Energy Storage Test Pad (ESTP) for functional testing and then to the BCIL for performance evaluation. The technologies that will be tested are electro-chemical energy storage systems comprising of lead acid, lithium-ion or zinc-bromide. GS Battery and EPC Power have developed an energy storage systemmore » that utilizes zinc-bromide flow batteries to save fuel on a military microgrid. This report contains the testing results and some limited analysis of performance of the GS Battery, EPC Power HES RESCU.« less

  1. Designing solid-liquid interphases for sodium batteries.

    PubMed

    Choudhury, Snehashis; Wei, Shuya; Ozhabes, Yalcin; Gunceler, Deniz; Zachman, Michael J; Tu, Zhengyuan; Shin, Jung Hwan; Nath, Pooja; Agrawal, Akanksha; Kourkoutis, Lena F; Arias, Tomas A; Archer, Lynden A

    2017-10-12

    Secondary batteries based on earth-abundant sodium metal anodes are desirable for both stationary and portable electrical energy storage. Room-temperature sodium metal batteries are impractical today because morphological instability during recharge drives rough, dendritic electrodeposition. Chemical instability of liquid electrolytes also leads to premature cell failure as a result of parasitic reactions with the anode. Here we use joint density-functional theoretical analysis to show that the surface diffusion barrier for sodium ion transport is a sensitive function of the chemistry of solid-electrolyte interphase. In particular, we find that a sodium bromide interphase presents an exceptionally low energy barrier to ion transport, comparable to that of metallic magnesium. We evaluate this prediction by means of electrochemical measurements and direct visualization studies. These experiments reveal an approximately three-fold reduction in activation energy for ion transport at a sodium bromide interphase. Direct visualization of sodium electrodeposition confirms large improvements in stability of sodium deposition at sodium bromide-rich interphases.The chemistry at the interface between electrolyte and electrode plays a critical role in determining battery performance. Here, the authors show that a NaBr enriched solid-electrolyte interphase can lower the surface diffusion barrier for sodium ions, enabling stable electrodeposition.

  2. Rocuronium Bromide Inhibits Inflammation and Pain by Suppressing Nitric Oxide Production and Enhancing Prostaglandin E2 Synthesis in Endothelial Cells.

    PubMed

    Baek, Sang Bin; Shin, Mal Soon; Han, Jin Hee; Moon, Sang Woong; Chang, Boksoon; Jeon, Jung Won; Yi, Jae Woo; Chung, Jun Young

    2016-12-01

    Rocuronium bromide is a nondepolarizing neuromuscular blocking drug and has been used as an adjunct for relaxation or paralysis of the skeletal muscles, facilitation of endotracheal intubation, and improving surgical conditions during general anesthesia. However, intravenous injection of rocuronium bromide induces injection pain or withdrawal movement. The exact mechanism of rocuronium bromide-induced injection pain or withdrawal movement is not yet understood. We investigated whether rocuronium bromide treatment is involved in the induction of inflammation and pain in vascular endothelial cells. For this study, calf pulmonary artery endothelial (CPAE) cells were used, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Western blot, nitric oxide detection, and prostaglandin E 2 immunoassay were conducted. Rocuronium bromide treatment inhibited endothelial nitric oxide synthase and suppressed nitric oxide production in CPAE cells. Rocuronium bromide activated cyclooxygenase-2, inducible nitric oxide synthase and increased prostaglandin E 2 synthesis in CPAE cells. Rocuronium bromide induced inflammation and pain in CPAE cells. Suppressing nitric oxide production and enhancing prostaglandin E 2 synthesis might be associated with rocuronium bromide-induced injection pain or withdrawal movement.

  3. Power Plant Bromide Discharges and Downstream Drinking Water Systems in Pennsylvania.

    PubMed

    Good, Kelly D; VanBriesen, Jeanne M

    2017-10-17

    Coal-fired power plants equipped with wet flue gas desulfurization (FGD) systems have been implicated in increasing bromide levels and subsequent increases in disinfection byproducts at downstream drinking water plants. Bromide was not included as a regulated constituent in the recent steam electric effluent limitations guidelines and standards (ELGs) since the U.S. EPA analysis suggested few drinking water facilities would be affected by bromide discharges from power plants. The present analysis uses a watershed approach to identify Pennsylvania drinking water intakes downstream of wet FGD discharges and to assess the potential for bromide discharge effects. Twenty-two (22) public drinking water systems serving 2.5 million people were identified as being downstream of at least one wet FGD discharge. During mean August conditions (generally low-flow, minimal dilution) in receiving rivers, the median predicted bromide concentrations contributed by wet FGD at Pennsylvania intake locations ranged from 5.2 to 62 μg/L for the Base scenario (including only natural bromide in coal) and from 16 to 190 μg/L for the Bromide Addition scenario (natural plus added bromide for mercury control); ranges depend on bromide loads and receiving stream dilution capacity.

  4. Peracetic acid oxidation of saline waters in the absence and presence of H ₂O ₂: secondary oxidant and disinfection byproduct formation.

    PubMed

    Shah, Amisha D; Liu, Zheng-Qian; Salhi, Elisabeth; Höfer, Thomas; von Gunten, Urs

    2015-02-03

    Peracetic acid (PAA) is a disinfectant considered for use in ballast water treatment, but its chemical behavior in such systems (i.e., saline waters) is largely unknown. In this study, the reactivity of PAA with halide ions (chloride and bromide) to form secondary oxidants (HOCl, HOBr) was investigated. For the PAA-chloride and PAA-bromide reactions, second-order rate constants of (1.47 ± 0.58) × 10(-5) and 0.24 ± 0.02 M(-1) s(-1) were determined for the formation of HOCl or HOBr, respectively. Hydrogen peroxide (H2O2), which is always present in PAA solutions, reduced HOCl or HOBr to chloride or bromide, respectively. As a consequence, in PAA-treated solutions with [H2O2] > [PAA], the HOBr (HOCl) steady-state concentrations were low with a limited formation of brominated (chlorinated) disinfection byproducts (DBPs). HOI (formed from the PAA-iodide reaction) affected this process because it can react with H2O2 back to iodide. H2O2 is thus consumed in a catalytic cycle and leads to less efficient HOBr scavenging at even low iodide concentrations (<1 μM). In PAA-treated solutions with [H2O2] < [PAA] and high bromide levels, mostly brominated DBPs are formed. In synthetic water, bromate was formed from the oxidation of bromide. In natural brackish waters, bromoform (CHBr3), bromoacetic acid (MBAA), dibromoacetic acid (DBAA), and tribromoacetic acid (TBAA) formed at up to 260, 106, 230, and 89 μg/L, respectively for doses of 2 mM (ca. 150 mg/L) PAA and [H2O2] < [PAA]. The same brackish waters, treated with PAA with [H2O2] ≫ [PAA], similar to conditions found in commercial PAA solutions, resulted in no trihalomethanes and only low haloacetic acid concentrations.

  5. How Important Is the Organic Part of Lead Halide Perovskite Photovoltaic Cells? Efficient CsPbBr3 Cells.

    PubMed

    Kulbak, Michael; Cahen, David; Hodes, Gary

    2015-07-02

    Hybrid organic-inorganic lead halide perovskite photovoltaic cells have already surpassed 20% conversion efficiency in the few years that they have been seriously studied. However, many fundamental questions still remain unanswered as to why they are so good. One of these is "Is the organic cation really necessary to obtain high quality cells?" In this study, we show that an all-inorganic version of the lead bromide perovskite material works equally well as the organic one, in particular generating the high open circuit voltages that are an important feature of these cells.

  6. The distribution of bromide in water in the Floridan aquifer system, Duval County, northeastern Florida

    USGS Publications Warehouse

    German, E.R.; Taylor, G.F.

    1995-01-01

    Although Duval County, Florida, has ample ground-water resources for public supply, the potential exists for a problem with excessive disinfectant by-products. These disinfectant by-products result from the treatment of raw water containing low concentrations of bromide and naturally occurring organic compounds. Because of this potential problem, the relation of bromide concentrations to aquifer tapped, well location and depth, and chemical characteristics of water in the Floridan aquifer system underlying Duval County were studied to determine if these relations could be applied to delineate water with low-bromide concentrations for future supplies. In 1992, water samples from 106 wells that tap the Floridan aquifer system were analyzed for bromide and major dissolved constituents. A comparison of bromide concentrations from the 1992 sampling with data from earlier studies (1979-80) indicates that higher bromide concentrations were detected during the earlier studies. The difference between the old and new data is probably because of a change in analytical methodology in the analysis of samples. Bromide concentrations exceeded the detection limit (0.10 milligrams per liter) in water from 28 of the 106 wells (26 percent) sampled in 1992. The maximum concentration was 0.56 milligrams per liter. There were no relations between bromide and major dissolved constituents, well depth, or aquifer tapped that would be useful for determining bromide concentrations. Areal patterns of bromide occurrence are not clearly defined, but areas with relatively high bromide concentrations tend to be located in a triangular area near the community of Sunbeam, Florida, and along the St. Johns River throughout Duval County.

  7. Validation of an automated fluorescein method for determining bromide in water

    USGS Publications Warehouse

    Fishman, M. J.; Schroder, L.J.; Friedman, L.C.

    1985-01-01

    Surface, atmospheric precipitation and deionized water samples were spiked with ??g l-1 concentrations of bromide, and the solutions stored in polyethylene and polytetrafluoroethylene bottles. Bromide was determined periodically for 30 days. Automated fluorescein and ion chromatography methods were used to determine bromide in these prepared samples. Analysis of the data by the paired t-test indicates that the two methods are not significantly different at a probability of 95% for samples containing from 0.015 to 0.5 mg l-1 of bromide. The correlation coefficient for the same sets of paired data is 0.9987. Recovery data, except for the surface water samples to which 0.005 mg l-1 of bromide was added, range from 89 to 112%. There appears to be no loss of bromide from solution in either type of container.Surface, atmospheric precipitation and deionized water samples were spiked with mu g l** minus **1 concentrations of bromide, and the solutions stored in polyethylene and polytetrafluoroethylene bottles. Bromide was determined periodically for 30 days. Automated fluorescein and ion chromatography methods were used to determine bromide in these prepared samples. Analysis of the data by the paired t-test indicates that the two methods are not significantly different at a probability of 95% for samples containing from 0. 015 to 0. 5 mg l** minus **1 of bromide. The correlation coefficient for the same sets of paired data is 0. 9987. Recovery data, except for the surface water samples to which 0. 005 mg l** minus **1 of bromide was added, range from 89 to 112%. Refs.

  8. Self-assembly and alignment of semiconductor nanoparticles on cellulose nanocrystals

    Treesearch

    Sonal Padalkar; Jeff R. Capadona; Stuart J. Rowan; Christoph Weder; Robert J. Moon; Lia A. Stanciu

    2011-01-01

    The synthesis of cadmium sulfide (CdS), zinc sulfide (ZnS), and lead sulfide (PbS) nanoparticle chains on cellulose nanocrystal (CNC) templates can be accomplished by the reaction of the precursor salts. The use of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), was critical for the synthesis of well-defined semiconductor nanoparticle chains on the...

  9. Comparison of Heat and Bromide as Ground Water Tracers Near Streams

    USGS Publications Warehouse

    Constantz, J.; Cox, M.H.; Su, G.W.

    2003-01-01

    Heat and bromide were compared as tracers for examining stream/ground water exchanges along the middle reaches of the Santa Clara River, California, during a 10-hour surface water sodium bromide injection test. Three cross sections that comprise six shallow (<1 m) piezometers were installed at the upper, middle, and lower sections of a 17 km long study reach, to monitor temperatures and bromide concentrations in the shallow ground water beneath the stream. A heat and ground water transport simulation model and a closely related solute and ground water transport simulation model were matched up for comparison of simulated and observed temperatures and bromide concentrations in the streambed. Vertical, one-dimensional simulations of sediment temperature were fitted to observed temperature results, to yield apparent streambed hydraulic conductivities in each cross section. The temperature-based hydraulic conductivities were assigned to a solute and ground water transport model to predict sediment bromide concentrations, during the sodium bromide injection test. Vertical, one-dimensional simulations of bromide concentrations in the sediments yielded a good match to the observed bromide concentrations, without adjustment of any model parameters except solute dispersivities. This indicates that, for the spatial and temporal scales examined on the Santa Clara River, the use of heat and bromide as tracers provide comparable information with respect to apparent hydraulic conductivities and fluxes for sediments near streams. In other settings, caution should be used due to differences in the nature of conservative (bromide) versus nonconservative (heat) tracers, particularly when preferential flowpaths are present.

  10. N-heterocycle carbene (NHC)-ligated cyclopalladated N,N-dimethylbenzylamine: a highly active, practical and versatile catalyst for the Heck-Mizoroki reaction.

    PubMed

    Peh, Guang-Rong; Kantchev, Eric Assen B; Zhang, Chi; Ying, Jackie Y

    2009-05-21

    The wide dissemination of catalytic protocols in academic and industrial laboratories is facilitated by the development of catalysts that are not only highly active but also user-friendly, stable to moisture, air and long term storage and easy to prepare on a large scale. Herein we describe a protocol for the Heck-Mizoroki reaction mediated by cyclopalladated N,N-dimethylbenzylamine (dmba) ligated with a N-heterocyclic carbene, 1,3-bis(mesityl)imidazol-2-ylidene (IMes), that fulfils these criteria. The precatalyst can be synthesized on approximately 100 g scale by a tri-component, sequential, one-pot reaction of N,N-dimethylbenzylamine, PdCl2 and IMes.HCl in refluxing acetonitrile in air in the presence of K2CO3. This single component catalyst is stable to air, moisture and long term storage and can be conveniently dispensed as a stock solution in NMP. It mediates the Heck-Mizoroki reaction of a range of aryl- and heteroaryl bromides in reagent grade NMP at the 0.1-2 mol% range without the need for rigorous anhydrous techniques or a glovebox, and is active even in air. The catalyst is capable of achieving very high levels of catalytic activity (TON of up to 5.22 x 10(5)) for the coupling of a deactivated arylbromide, p-bromoanisole, with tBu acrylate as a benchmark substrate pair. A wide range of aryl bromides, iodides and, for the first time with a NHC-Pd catalyst, a triflate was coupled with diverse acrylate derivatives (nitrile, tert-butyl ester and amides) and styrene derivatives. The use of excess (>2 equiv.) of the aryl bromide and tert-butyl acrylate leads to mixture of tert-butyl beta,beta-diarylacrylate and tert-butyl cinnamate derivatives depending on the substitution pattern of the aryl bromide. Electron rich m- and p-substituted arylbromides give the diarylated products exclusively, whereas electron-poor aryl bromides give predominantly mono-arylated products. For o-substituted aryl bromides, no doubly arylated products could be obtained under any conditions. Overall, the active catalyst (IMes-Pd) shows higher activity with electron-rich aryl halides, a marked difference compared with the more commonly used phosphane-Pd or non-ligated Pd catalysts.

  11. 21 CFR 522.275 - N-Butylscopolammonium bromide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false N-Butylscopolammonium bromide. 522.275 Section 522....275 N-Butylscopolammonium bromide. (a) Specifications. Each milliliter of solution contains 20 milligrams (mg) N-butylscopolammonium bromide. (b) Sponsor. See No. 000010 in § 510.600(c) of this chapter...

  12. 21 CFR 522.275 - N-Butylscopolammonium bromide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false N-Butylscopolammonium bromide. 522.275 Section 522....275 N-Butylscopolammonium bromide. (a) Specifications. Each milliliter of solution contains 20 milligrams (mg) N-butylscopolammonium bromide. (b) Sponsor. See No. 000010 in § 510.600(c) of this chapter...

  13. Palladium-Catalyzed Borylation of Primary Alkyl Bromides

    PubMed Central

    Joshi-Pangu, Amruta; Ma, Xinghua; Diane, Mohamed; Iqbal, Sidra; Kribs, Robert J.; Huang, Richard; Wang, Chao-Yuan

    2012-01-01

    A mild Pd-catalyzed process for the borylation of alkyl bromides has been developed using bis(pinacolato)diboron as a boron source. This process accommodates the use of a wide range of functional groups on the alkyl bromide substrate. Primary bromides react with complete selectivity in the presence of a secondary bromide. The generality of this approach is demonstrated by its extension to the use of alkyl iodides and alkyl tosylates, as well as borylation reactions employing bis(neopentyl glycolato)diboron as the boron source. PMID:22774861

  14. Indirect spectrophotometric determination of traces of bromide in water

    USGS Publications Warehouse

    Fishman, M. J.; Skougstad, M.W.

    1963-01-01

    A rapid, accurate, and sensitive indirect spectrophotometric method for the determination of bromide in natural waters is based on the catalytic effect of bromide on the oxidation of iodine to iodate by potassium permanganate in sulfuric acid solution. The method is applicable to concentrations ranging from 1 to 100 ??g. of bromide per liter, but may be modified to extend the concentration range. Most ions commonly occurring in water do not interfere. The standard deviation is 2.9 at bromide concentrations of 100 ??g. per liter and less at lower concentrations. The determination of bromide in samples containing known added amounts gave values ranging from 99 to 105% of the concentration calculated to be present.

  15. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    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 the...

  16. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 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 the...

  17. An improved method for large-scale preparation of negatively and positively supercoiled plasmid DNA.

    PubMed

    Barth, Marita; Dederich, Debra; Dedon, Peter

    2009-07-01

    A rigorous understanding of the biological function of superhelical tension in cellular DNA requires the development of new tools and model systems for study. To this end, an ethidium bromide[#x02013]free method has been developed to prepare large quantities of either negatively or positively super-coiled plasmid DNA. The method is based upon the known effects of ionic strength on the direction of binding of DNA to an archaeal histone, rHMfB, with low and high salt concentrations leading to positive and negative DNA supercoiling, respectively. In addition to fully optimized conditions for large-scale (>500 microg) supercoiling reactions, the method is advantageous in that it avoids the use of mutagenic ethidium bromide, is applicable to chemically modified plasmid DNA substrates, and produces both positively and negatively supercoiled DNA using a single set of reagents.

  18. Lead bromide-based layered perovskite Langmuir-Blodgett films having π-conjugated molecules as organic layer prepared by using squeezed out technique

    NASA Astrophysics Data System (ADS)

    Era, Masanao; Shironita, Yu; Soda, Koichi

    2018-03-01

    Using the squeezed out technique, we successfully prepared PbBr-based layered perovskite Langmuir-Blodgett (LB) films, which have π-conjugated materials as an organic layer (i.e., a phenylenevinylene oligomer, a dithienylethene derivative, and a π-conjugated polyfluorene derivative). The mixed monolayers of π-conjugated materials and octadecylammonium bromide were spread on an aqueous subphase containing saturated PbBr2. During pressing, octadecylammonium molecules were squeezed from the mixed monolayer, and the squeezed ammonium molecules formed the PbBr-based layered perovskite structure at the air-aqueous subphase interface. The monolayers with the PbBr-based layered perovskite structure could be deposited on fused quartz substrates by the LB technique. In addition to the preparation procedure, the structural and optical properties of the layered perovskite LB films and their formation mechanism are reported in this paper.

  19. Selective Synthesis of 5- or 6-Aryl Octahydrocyclopenta[b]pyrroles from a Common Precursor Through Control of Competing Pathways in a Pd-Catalyzed Reaction

    PubMed Central

    Ney, Joshua E.; Wolfe, John P.

    2009-01-01

    The Pd/phosphine-catalyzed reaction of 1 with aryl bromides leads to the selective synthesis of either 6-aryl octahydrocyclopenta[b]pyrroles (3), the corresponding 5-aryl isomers 5, diarylamine 2, or hexahydrocyclopenta[b]pyrrole 4 depending on the structure of the phosphine ligand. These transformations are effective with a variety of different aryl bromides, and provide 3-5 with excellent levels of diastereoselectivity (dr ≥ 20:1). The changes in product distribution are believed to derive from the influence of Pd-catalyst structure on the relative rates of reductive elimination, β-hydride elimination, alkene insertion, and alkene dissociation processes in a mechanistically complex reaction. The effect of phosphine ligand structure on product distribution is described in detail, along with analysis of a proposed mechanism for these transformations. PMID:15954769

  20. Selective Cleavage of the Aryl Ether Bonds in Lignin for Depolymerization by Acidic Lithium Bromide Molten Salt Hydrate under Mild Conditions.

    PubMed

    Yang, Xiaohui; Li, Ning; Lin, Xuliang; Pan, Xuejun; Zhou, Yonghong

    2016-11-09

    The present study demonstrates that the concentrated lithium bromide (LiBr) solution with acid as catalyst was able to selectively cleave the β-O-4 aryl ether bond and lead to lignin depolymerization under mild conditions (e.g., in 60% LiBr with 0.3 M HCl at 110 °C for 2 h). Four industrial lignins from different pulping and biorefining processes, including softwood kraft lignin (SKL), hardwood kraft lignin (HKL), softwood ethanol organosolv lignin (EOL), and acid corncob lignin (ACL), were treated in the LiBr solution. The molecular weight, functional group, and interunit linkages of the lignins were characterized using GPC, FTIR, and NMR. The results indicated that the β-O-4 aryl ether bonds of the lignins were selectively cleaved, and both LiBr and HCl played crucial roles in catalyzing the cleavage of the ether bonds.

  1. Aqueous photochemical reactions of chloride, bromide, and iodide ions in a diode-array spectrophotometer. Autoinhibition in the photolysis of iodide ions.

    PubMed

    Kalmár, József; Dóka, Éva; Lente, Gábor; Fábián, István

    2014-03-28

    The aqueous photoreactions of three halide ions (chloride, bromide and iodide) were studied using a diode array spectrophotometer to drive and detect the process at the same time. The concentration and pH dependences of the halogen formation rates were studied in detail. The experimental data were interpreted by improving earlier models where the cage complex of a halogen atom and an electron has a central role. The triiodide ion was shown to exert a strong inhibiting effect on the reaction sequence leading to its own formation. An assumed chemical reaction between the triiodide ion and the cage complex interpreted the strong autoinhibition effect. It is shown that there is a real danger of unwanted interference from the photoreactions of halide ions when halide salts are used as supporting electrolytes in spectrophotometric experiments using a relatively high intensity UV light source.

  2. The Rise of Highly Efficient and Stable Perovskite Solar Cells.

    PubMed

    Grätzel, Michael

    2017-03-21

    Recently, metal halide perovskite solar cells (PSCs) of the general formular ABX 3 where A is a monovalent cation, that is, methylammonium (MA) CH 3 NH 3 +• , formamidinium CH 2 (NH 2 ) 2 + , Cs + , or Rb + , B stands for Pb(II) or Sn(II), and X for iodide or bromide have achieved solar to electric power conversion efficiencies (PCEs) above 22%, exceeding the efficiency of the present market leader polycrystalline silicon while using 1000 times less light harvesting material and simple solution processing for their fabrication. The top performing devices all employ formulations containing a mixture of up to four A cations and iodide as well as a small fraction of bromide as anion, whose emergence will be described in this Commentary. Apart from leading the current PV efficiency race, these new perovskite materials exhibit intense electroluminescence and an extraordinarily high stability under heat and light stress.

  3. EFFECT OF BROMIDE ION IN WATER TREATMENT. 2. A LITERATURE REVIEW OF OZONE AND BROMIDE ION INTERACTIONS AND THE FORMATION OF ORGANIC BROMINE COMPOUNDS

    EPA Science Inventory

    Where bromide ion is found in water used as a source of drinking water, and chlorination is used for disinfection, bromide ion is oxidized to bromine and can result in the formation of organic bromine compounds. There are presently no treatment techniques available for economic r...

  4. Automated determination of bromide in waters by ion chromatography with an amperometric detector

    USGS Publications Warehouse

    Pyen, G.S.; Erdmann, D.E.

    1983-01-01

    An automated ion chromatograph, including a program controller, an automatic sampler, an integrator, and an amperometric detector, was used to develop a procedure for the determination of bromide in rain water and many ground waters. Approximately 10 min is required to obtain a chromatogram. The detection limit for bromide is 0.01 mg l-1 and the relative standard deivation is <5% for bromide concentrations between 0.05 and 0.5 mg l-1. Chloride interferes if the chloride-to-bromide ratio is greater than 1 000:1 for a range of 0.01-0.1 mg l-1 bromide; similarly, chloride interferes in the 0.1-1.0 mg l-1 range if the ratio is greater than 5 000:1. In the latter case, a maximum of 2 000 mg l-1 of chloride can be tolerated. Recoveries of known concentrations of bromide added to several samples, ranged from 97 to 110%. ?? 1983.

  5. Bromism caused by mix-formulated analgesic injectables.

    PubMed

    Hsieh, P F; Tsan, Y T; Hung, D Z; Hsu, C L; Lee, Y C; Chang, M H

    2007-12-01

    Bromism, chronic bromide intoxication, can be caused by a variety of medicines, but bromism due to pain-relieving injectable medications has not been reported. In this study, the methods used were internet searching on bromide-containing injectables available in Taiwan and the first case report of bromism due to mixed-formulated injectable medication. Many analgesic/antipyretic and antihistamine injections containing bromides are still being used in Taiwan. They contain sodium bromide up to 1000 mg/ampoule or calcium bromide up to 800 mg/amp. A 25-year-old female suffered from forgetfulness and unstable gait after long-term frequent injections of a preparation to relieve head and neck pain. Blood tests showed hyperchloremia (171 mEq/L) and a negative anion gap (-48.7 mEq/L). Serum bromide measured 2150 mg/L. She recovered completely in 3 days with saline treatment. Many bromide-containing injections are still being used in Taiwan. Clinicians should keep alert on this issue to avoid iatrogenic bromism or making misdiagnoses.

  6. Bromide's effect on DBP formation, speciation, and control; Part 1: Ozonation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shukairy, H.M.; Summers, R.S.; Miltner, R.J.

    1994-06-01

    The effect of variable ozone dosage and bromide concentration on the formation of organic disinfection by-products (DBPs) and bromate were evaluated. Low ozone dosages resulted in oxidation of organic precursors, yielding decreases in the formation potential for total trihalomethanes (THMs), six haloacetic acids (HAAs), and total organic halide (TOX). Increasing the ozone dosage oxidized bromide to bromate, decreasing the bromide for incorporation into DBPs. Bromate concentrations were linearly correlated with ozone residuals. Changes in the bromine incorporation factors n and n[prime] reflected differences in the resulting speciation of THMs and HAAs, respectively. Because TOX measurements based on chloride equivalence maymore » underestimate the halogenated DBP yield for high-bromide waters, a procedure is described whereby bromide and bromate concentrations were used to correct the TOX measurement.« less

  7. Ipratropium bromide in patients with nocturnal asthma.

    PubMed Central

    Cox, I. D.; Hughes, D. T.; McDonnell, K. A.

    1984-01-01

    Fourteen patients with nocturnal asthma were recruited to a two period crossover trial which compared a run-in period on nightly salbutamol (200 micrograms) with a period on nightly ipratropium bromide (160 micrograms) and a period on nightly salbutamol plus ipratropium at night. Morning dipping, as assessed by the fall in peak flow overnight, was significantly reduced in the periods when ipratropium bromide was taken. Peak flow in the morning and also at night was improved when taking ipratropium bromide. Ipratropium bromide in adequate dosage appears to be effective in reducing morning dipping in asthma. PMID:6236436

  8. Alternatives to Methyl Bromide (1993)

    EPA Pesticide Factsheets

    The report examines the alternatives that have been discussed as substitutes for current methyl bromide uses if methyl bromide should no longer be available and discusses the economic implications of such a phaseout.

  9. Prostate cancer and toxicity from critical use exemptions of methyl bromide: Environmental protection helps protect against human health risks

    PubMed Central

    2012-01-01

    Background Although ozone-depleting methyl bromide was destined for phase-out by 2005, it is still widely applied as a consequence of various critical-use-exemptions and mandatory international regulations aiming to restrict the spread of pests and alien species (e.g. in globalized transport and storage). The withdrawal of methyl bromide because of its environmental risk could fortuitously help in the containment of its human toxicity. Methods We performed a systematic review of the literature, including in vitro toxicological and epidemiological studies of occupational and community exposure to the halogenated hydrocarbon pesticide methyl bromide. We focused on toxic (especially chronic) or carcinogenic effects from the use of methyl bromide, on biomonitoring data and reference values. Eligible epidemiological studies were subjected to meta-analysis. Results Out of the 542 peer reviewed publications between 1990-2011, we found only 91 referring to toxicity of methyl bromide and 29 using the term "carcinogenic", "neoplastic" or "mutagenic". Several studies provide new additional data pertaining to the mechanistic aspects of methyl bromide toxicity. Few studies have performed a detailed exposure assessment including biomonitoring. Three evaluated epidemiological studies assessed a possible association between cancer and methyl bromide. Overall, exposure to methyl bromide is associated with an increased risk of prostate cancer OR, 1.21; 95% CI (0,98-1.49), P = 0.076. Two epidemiological studies have analyzed environmental, non-occupational exposure to methyl bromide providing evidence for its health risk to the general public. None of the epidemiological studies addressed its use as a fumigant in freight containers, although recent field and case reports do refer to its toxic effects associated with its use in shipping and storage. Conclusions Both the epidemiological evidence and toxicological data suggest a possible link between methyl bromide exposure and serious health problems, including prostate cancer risk from occupational and community exposure. The environmental risks of methyl bromide are not in doubt, but also its health risks, especially for genetically predisposed subjects, should not be underestimated. PMID:22284215

  10. Comparison of phenobarbital with bromide as a first-choice antiepileptic drug for treatment of epilepsy in dogs.

    PubMed

    Boothe, Dawn Merton; Dewey, Curtis; Carpenter, David Mark

    2012-05-01

    To compare efficacy and safety of treatment with phenobarbital or bromide as the first-choice antiepileptic drug (AED) in dogs. Double-blinded, randomized, parallel, clinical trial. 46 AED-naïve dogs with naturally occurring epilepsy. Study inclusion was based on age, history, findings on physical and neurologic examinations, and clinicopathologic test results. For either phenobarbital treatment (21 dogs) or bromide treatment (25), a 7-day loading dose period was initiated along with a maintenance dose, which was adjusted on the basis of monthly monitoring. Efficacy and safety outcomes were compared between times (baseline and study end [generally 6 months]) and between drugs. Phenobarbital treatment resulted in eradication of seizures (17/20 [85%]) significantly more often than did bromide (12/23 [52%]); phenobarbital treatment also resulted in a greater percentage decrease in seizure duration (88 ± 34%), compared with bromide (49 ± 75%). Seizure activity worsened in 3 bromide-treated dogs only. In dogs with seizure eradication, mean ± SD serum phenobarbital concentration was 25 ± 6 μg/mL (phenobarbital dosage, 4.1 ± 1.1 mg/kg [1.9 ± 0.5 mg/lb], p.o., q 12 h) and mean serum bromide concentration was 1.8 ± 0.6 mg/mL (bromide dosage, 31 ± 11 mg/kg [14 ± 5 mg/lb], p.o., q 12 h). Ataxia, lethargy, and polydipsia were greater at 1 month for phenobarbital-treated dogs; vomiting was greater for bromide-treated dogs at 1 month and study end. Both phenobarbital and bromide were reasonable first-choice AEDs for dogs, but phenobarbital was more effective and better tolerated during the first 6 months of treatment.

  11. Abiotic Formation of Methyl Halides in the Terrestrial Environment

    NASA Astrophysics Data System (ADS)

    Keppler, F.

    2011-12-01

    Methyl chloride and methyl bromide are the most abundant chlorine and bromine containing organic compounds in the atmosphere. Since both compounds have relatively long tropospheric lifetimes they can effectively transport halogen atoms from the Earth's surface, where they are released, to the stratosphere and following photolytic oxidation form reactive halogen gases that lead to the chemical destruction of ozone. Methyl chloride and methyl bromide account for more than 20% of the ozone-depleting halogens delivered to the stratosphere and are predicted to grow in importance as the chlorine contribution to the stratosphere from anthropogenic CFCs decline. Today methyl chloride and methyl bromide originate mainly from natural sources with only a minor fraction considered to be of anthropogenic origin. However, until as recently as 2000 most of the methyl chloride and methyl bromide input to the atmosphere was considered to originate from the oceans, but investigations in recent years have clearly demonstrated that terrestrial sources such as biomass burning, wood-rotting fungi, coastal salt marshes, tropical vegetation and organic matter degradation must dominate the atmospheric budgets of these trace gases. However, many uncertainties still exist regarding strengths of both sources and sinks, as well as the mechanisms of formation of these naturally occurring halogenated gases. A better understanding of the atmospheric budget of both methyl chloride and methyl bromide is therefore required for reliable prediction of future ozone depletion. Biotic and abiotic methylation processes of chloride and bromide ion are considered to be the dominant pathways of formation of these methyl halides in nature. In this presentation I will focus on abiotic formation processes in the terrestrial environment and the potential parameters that control their emissions. Recent advances in our understanding of the abiotic formation pathway of methyl halides will be discussed. This will include a consideration on how stable isotope studies assisted advancements in this subject area. For example, it has been shown that the methoxyl groups of lignin and pectin which together constitute the bulk of the C1 plant pool have a carbon isotope signature significantly depleted in 13C. Plant-derived C1 volatile organic compounds (VOCs) are also highly depleted in 13C compared with Cn+1 VOCs. These observations suggest that the plant methoxyl pool is the predominant source of methyl halides released from senescent and dead plant litter. The distinct 13C depletion of plant methoxyl groups and naturally produced methyl halides may provide a helpful tool in constraining complex environmental processes and therefore improve our understanding of the global cycles of atmospheric methyl halides.

  12. METHOD OF SEPARATING URANIUM, PLUTONIUM AND FISSION PRODUCTS BY BROMINATION AND DISTILLATION

    DOEpatents

    Jaffey, A.H.; Seaborg, G.T.

    1958-12-23

    The method for separation of plutonium from uranium and radioactive fission products obtained by neutron irradiation of uranlum consists of reacting the lrradiated material with either bromine, hydrogen bromide, alumlnum bromide, or sulfur and bromine at an elevated temperature to form the bromides of all the elements, then recovering substantlally pure plutonium bromide by dlstillatlon in combinatlon with selective condensatlon at prescribed temperature and pressure.

  13. Subsurface drip application of alternative fumigants to methyl bromide for controlling nematodes in replanted grapevines.

    PubMed

    Cabrera, J Alfonso; Wang, Dong; Schneider, Sally M; Hanson, Bradley D

    2012-05-01

    Many California grape growers use preplant fumigation to ensure uniform and healthy grapevine establishment in replant situations. A field study was conducted to evaluate the performance of subsurface drip-applied chemical alternatives to methyl bromide on plant-parasitic nematodes, plant vigor and fruit yield during the 6 year period following replanting. Subsurface drip fumigation with 1,3-dichloropropene plus chloropicrin and with iodomethane plus chloropicrin had generally similar nematicide activity as methyl bromide in three grape types, while sodium azide was less effective. The combination of 1,3-dichloropropene plus chloropicrin enhanced vine vigor similarly to methyl bromide. However, all plots treated with alternative fumigants produced less fruit yield than methyl bromide over the 4 years of evaluation. Subsurface drip fumigation with alternative chemicals to methyl bromide generally provided adequate management of plant-parasitic nematodes during the vine establishment period. However, further research is required to increase the performance of alternative chemicals against other components of the replant problem, as grape yield in vines grown in the alternative treatments was lower than in methyl bromide. Copyright © 2011 Society of Chemical Industry.

  14. Calix[4]pyrrole: A New Ion-Pair Receptor As Demonstrated by Liquid-Liquid Extraction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wintergerst, Mr. Matthieu; Levitskaia, Tatiana G.; Moyer, Bruce A

    Solvent-extraction studies provide confirming evidence that meso-octamethylcalix[4]pyrrole acts as an ion-pair receptor for cesium chloride and cesium bromide in nitrobenzene solution. The stoichiometry of the interaction under extraction conditions from water to nitrobenzene was determined from plots of the cesium distribution ratios vs cesium salt and receptor concentration, indicating the formation of an ionpaired 1:1:1 cesium:calix[4]pyrrole:halide complex. The extraction results were modeled to evaluate the equilibria inherent to the solvent-extraction system, with either chloride or bromide. The binding energy between the halide anion and the calix[4]pyrrole was found to be about 7 kJ/mol larger for cesium chloride than for themore » cesium bromide. The ion-pairing free energies between the calix[4]pyrrole-halide complex and the cesium cation are nearly the same within experimental uncertainty for either halide, consistent with a structural model in which the Cs+ cation resides in the calix bowl. These results are unexpected since nitrobenzene is a polar solvent that generally leads to dissociated complexes in the organic phase when used as a diluent in extraction studies of univalent ions. Control studies involving nitrate revealed no evidence of ion pairing for CsNO3 under conditions identical to those where it is observed for CsCl and CsBr.« less

  15. Calix[4]pyrrole: A New Ion-Pair Receptor As Demonstrated by Liquid-Liquid Extraction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wintergerst, Mr. Matthieu; Levitskaia, Tatiana G.; Moyer, Bruce A

    Solvent extraction studies provide confirming evidence that meso-octamethylcalix[4]pyrrole acts as an ion-pair receptor for cesium chloride and cesium bromide in nitrobenzene solution. The stoichiometry of the interaction under extraction conditions from water to nitrobenzene was determined from plots of the cesium distribution ratios vs. cesium salt and receptor concentration, indicating the formation of an ion-paired 1:1:1 cesium:calix[4]pyrrole:halide complex. The extraction results were modeled to evaluate the equilibria inherent to the solvent extraction system, either with chloride or bromide. The binding energy between the halide anion and the calix[4]pyrrole was found to be about 7 kJ/mol larger for cesium chloride thanmore » for the cesium bromide. The ion-pairing free energies between the calix[4]pyrrole-halide complex and the cesium cation are nearly the same within experimental uncertainty for either halide, consistent with a structural model in which the Cs+ cation resides in the calix bowl. These results are unexpected since nitrobenzene is a very polar solvent that generally leads to dissociated complexes in the organic phase when used as a diluent in extraction studies of univalent ions. Control studies involving nitrate revealed no evidence of ion-pairing for CsNO3 under conditions identical to those where it is observed for CsCl and CsBr.« less

  16. Dynamic Impact of Electrode Materials on Interface of Single-Crystalline Methylammonium Lead Bromide Perovskite

    DOE PAGES

    Tisdale, Jeremy T.; Muckley, Eric; Ahmadi, Mahshid; ...

    2018-06-19

    One of the current challenges in methylammonium lead halide (MAPbX 3) perovskite application research is understanding contact formation and interfacial phenomena for highly efficient and stable device performance. For semiconductors, development of contact formation is inseparable from device performance and stability. Single–crystalline MAPbX3 has become of great interest for perovskite devices in photodetectors, light–emitting diodes, and more recently in high–energy radiation detection. Deeper research is required to understand interfacial interactions in single–crystalline MAPbX 3. This article focuses on the dynamic impact of electrode metal (Au and Cr) on methylammonium lead bromide (MAPbBr 3) single crystals. It is studied how chargemore » transport properties of single crystal MAPbBr 3 can be tuned via electrode material selection at the metal/MAPbBr 3 interface to improve device performance with proper contact formation. The ability to create an ohmic–like or nonohmic contact by switching the electrode metal from Cr to Au, respectively, is demonstrated. It is observed that the interfacial charge transfer resistance (recombination resistance) of the Cr/MAPbBr 3 interface is 1.79 × 10 9 Ω, compared to 1.32 × 10 7 Ω for the Au/MAPbBr 3. Cr contacts can reduce hysteretic behavior by reducing interfacial recombination and interfacial polarization. Furthermore, these studies provide insight to metal/MAPbX 3 interfacial interactions toward device engineering for hole transport layer–free MAPbX 3 device structures.« less

  17. Dynamic Impact of Electrode Materials on Interface of Single-Crystalline Methylammonium Lead Bromide Perovskite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tisdale, Jeremy T.; Muckley, Eric; Ahmadi, Mahshid

    One of the current challenges in methylammonium lead halide (MAPbX 3) perovskite application research is understanding contact formation and interfacial phenomena for highly efficient and stable device performance. For semiconductors, development of contact formation is inseparable from device performance and stability. Single–crystalline MAPbX3 has become of great interest for perovskite devices in photodetectors, light–emitting diodes, and more recently in high–energy radiation detection. Deeper research is required to understand interfacial interactions in single–crystalline MAPbX 3. This article focuses on the dynamic impact of electrode metal (Au and Cr) on methylammonium lead bromide (MAPbBr 3) single crystals. It is studied how chargemore » transport properties of single crystal MAPbBr 3 can be tuned via electrode material selection at the metal/MAPbBr 3 interface to improve device performance with proper contact formation. The ability to create an ohmic–like or nonohmic contact by switching the electrode metal from Cr to Au, respectively, is demonstrated. It is observed that the interfacial charge transfer resistance (recombination resistance) of the Cr/MAPbBr 3 interface is 1.79 × 10 9 Ω, compared to 1.32 × 10 7 Ω for the Au/MAPbBr 3. Cr contacts can reduce hysteretic behavior by reducing interfacial recombination and interfacial polarization. Furthermore, these studies provide insight to metal/MAPbX 3 interfacial interactions toward device engineering for hole transport layer–free MAPbX 3 device structures.« less

  18. A novel cetyltrimethyl ammonium silver bromide complex and silver bromide nanoparticles obtained by the surfactant counterion.

    PubMed

    Liu, Xian-Hao; Luo, Xiao-Hong; Lu, Shu-Xia; Zhang, Jing-Chang; Cao, Wei-Liang

    2007-03-01

    A novel cetyltrimethyl ammonium silver bromide (CTASB) complex has been prepared simply through the reaction of silver nitrate with cetyltrimethyl ammonium bromide (CTAB) in aqueous solution at room temperature by controlling the concentration of CTAB and the molar ratio of CTAB to silver nitrate in the reaction solution, in which halogen in CTAB is used as surfactant counterion. The structure and thermal behavior of cetyltrimethyl ammonium silver bromide have been investigated by using X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), UV/vis spectroscopy, thermal analysis (TG-DTA), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that the complex possesses a metastable layered structure. Upon heating the CTASB aqueous dispersion to above 80 degrees C, the structure change of the complex took place and CTAB-capped nanosized silver bromide particles further formed.

  19. Structure/Property Relationships of Cyanate Ester Resins from Renewable Sources

    DTIC Science & Technology

    2013-04-11

    derived from lignin . These materials possess favorable thermal and water uptake properties with dry glass transition temperatures above 200°C and wet...distribution is unlimited. Creosol as a Monomer Source 7 • Input material cost is an important consideration for cyanate ester resins • Lignin is...from lignin • Oxidative and reductive coupling reactions lead to precursor phenols, which are then treated with cyanogen bromide to generate cyanate

  20. CsPbBr 3 Solar Cells: Controlled Film Growth through Layer-by-Layer Quantum Dot Deposition

    DOE PAGES

    Hoffman, Jacob B.; Zaiats, Gary; Wappes, Isaac; ...

    2017-10-25

    All inorganic cesium lead bromide (CsPbBr 3) perovskite is a more stable alternative to methylammonium lead bromide (MAPbBr 3) for designing high open-circuit voltage solar cells and display devices. Poor solubility of CsBr in organic solvents makes typical solution deposition methods difficult to adapt for constructing CsPbBr 3 devices. Our layer-by-layer methodology, which makes use of CsPbBr 3 quantum dot (QD) deposition followed by annealing, provides a convenient way to cast stable films of desired thickness. The transformation from QDs into bulk during thermal annealing arises from the resumption of nanoparticle growth and not from sintering as generally assumed. Additionally,more » a large loss of organic material during the annealing process is mainly from 1-octadecene left during the QD synthesis. Utilizing this deposition approach for perovskite photovoltaics is examined using typical planar architecture devices. Devices optimized to both QD spin-casting concentration and overall CsPbBr 3 thickness produce champion devices that reach power conversion efficiencies of 5.5% with a V oc value of 1.4 V. Finally, the layered QD deposition demonstrates a controlled perovskite film architecture for developing efficient, high open-circuit photovoltaic devices.« less

  1. CsPbBr 3 Solar Cells: Controlled Film Growth through Layer-by-Layer Quantum Dot Deposition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoffman, Jacob B.; Zaiats, Gary; Wappes, Isaac

    All inorganic cesium lead bromide (CsPbBr 3) perovskite is a more stable alternative to methylammonium lead bromide (MAPbBr 3) for designing high open-circuit voltage solar cells and display devices. Poor solubility of CsBr in organic solvents makes typical solution deposition methods difficult to adapt for constructing CsPbBr 3 devices. Our layer-by-layer methodology, which makes use of CsPbBr 3 quantum dot (QD) deposition followed by annealing, provides a convenient way to cast stable films of desired thickness. The transformation from QDs into bulk during thermal annealing arises from the resumption of nanoparticle growth and not from sintering as generally assumed. Additionally,more » a large loss of organic material during the annealing process is mainly from 1-octadecene left during the QD synthesis. Utilizing this deposition approach for perovskite photovoltaics is examined using typical planar architecture devices. Devices optimized to both QD spin-casting concentration and overall CsPbBr 3 thickness produce champion devices that reach power conversion efficiencies of 5.5% with a V oc value of 1.4 V. Finally, the layered QD deposition demonstrates a controlled perovskite film architecture for developing efficient, high open-circuit photovoltaic devices.« less

  2. Physicochemical and in vitro deposition properties of salbutamol sulphate/ipratropium bromide and salbutamol sulphate/excipient spray dried mixtures for use in dry powder inhalers.

    PubMed

    Corrigan, Deirdre O; Corrigan, Owen I; Healy, Anne Marie

    2006-09-28

    The physicochemical and aerodynamic properties of spray dried powders of the drug/drug mixture salbutamol sulphate/ipratropium bromide were investigated. The in vitro deposition properties of spray dried salbutamol sulphate and the spray dried drug/excipient mixtures salbutamol sulphate/lactose and salbutamol sulphate/PEG were also determined. Spray drying ipratropium bromide monohydrate resulted in a crystalline material from both aqueous and ethanolic solution. The product spray dried from aqueous solution consisted mainly of ipratropium bromide anhydrous. There was evidence of the presence of another polymorphic form of ipratropium bromide. When spray dried from ethanolic solution the physicochemical characterisation suggested the presence of an ipratropium bromide solvate with some anhydrous ipratropium bromide. Co-spray drying salbutamol sulphate with ipratropium bromide resulted in amorphous composites, regardless of solvent used. Particles were spherical and of a size suitable for inhalation. Twin impinger studies showed an increase in the fine particle fraction (FPF) of spray dried salbutamol sulphate compared to micronised salbutamol sulphate. Co-spray dried salbutamol sulphate:ipratropium bromide 10:1 and 5:1 systems also showed an increase in FPF compared to micronised salbutamol sulphate. Most co-spray dried salbutamol sulphate/excipient systems investigated demonstrated FPFs greater than that of micronised drug alone. The exceptions to this were systems containing PEG 4000 20% or PEG 20,000 40% both of which had FPFs not significantly different from micronised salbutamol sulphate. These two systems were crystalline unlike most of the other spray dried composites examined which were amorphous in nature.

  3. Sympathetic influence on the pupillary light response in three red-eared slider turtles (Trachemys scripta elegans).

    PubMed

    Dearworth, James R; Cooper, Lori J

    2008-01-01

    We investigated the effects of phenylephrine and its combination with vecuronium bromide on the iris of turtles to determine if the pupillary light response is affected by sympathetic innervation. Three red-eared slider turtles, Trachemys scripta elegans. Diameters of light-adapted pupils were tracked before and after topical application of drugs to eyes. Phenylephrine was applied independently; in a second group of trials, vecuronium bromide was applied with phenylephrine. Rates of pupil dilation in response to drugs were quantified by fitting data with time constant (tau) equations. Phenylephrine dilated the pupil 24%, tau = 29 min. Combination of phenylephrine with vecuronium bromide increased the pupil size 35%, and dilation was more rapid, tau = 14 min. We also were able to predict these time constants by performing different mathematical operations with an equation developed from a prior study using only vecuronium bromide. When this equation was subtracted from the equation for eyes treated with both vecuronium bromide and phenylephrine, the difference gave the observed tau for phenylephrine; when added to phenylephrine, the sum closely matched the tau for eyes treated with vecuronium bromide and phenylephrine. Further, the tau for vecuronium bromide treated eyes was predicted by subtracting the equation for phenylephrine from that of eyes treated with both vecuronium bromide and phenylephrine. Our results suggest that sympathetic innervation interacts with the parasympathetic pathway to control the pupillary light response in turtles.

  4. BROMIDE-OXIDANT INTERACTIONS AND THM (TRIHALOMETHANE) FORMATION: A LITERATURE REVIEW

    EPA Science Inventory

    The review focuses on the interactions, not only of bromide and chlorine, but also of bromide and two common oxidation alternatives to chlorine--chlorine dioxide and monochloramine. The data evaluations include discussions of reaction products, potentials for trihalomethane (THM)...

  5. 78 FR 32646 - Protection of Stratospheric Ozone: Request for Methyl Bromide Critical Use Exemption Applications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ... being treated/produced. List how many mills have been fumigated with methyl bromide over the last three... facilities. Dried Cured Pork Applicants must list how many facilities have been fumigated with methyl bromide...

  6. 76 FR 34700 - Protection of Stratospheric Ozone: Request for Methyl Bromide Critical Use Exemption Applications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ... pest control methods. List how many mills have been fumigated with methyl bromide over the last three... been fumigated with methyl bromide over the last three years, rate, volume and target CT of methyl...

  7. Advanced hydrogen electrode for hydrogen-bromide battery

    NASA Technical Reports Server (NTRS)

    Kosek, Jack A.; Laconti, Anthony B.

    1987-01-01

    Binary platinum alloys are being developed as hydrogen electrocatalysts for use in a hydrogen bromide battery system. These alloys were varied in terms of alloy component mole ratio and heat treatment temperature. Electrocatalyst evaluation, performed in the absence and presence of bromide ion, includes floating half cell polarization studies, electrochemical surface area measurements, X ray diffraction analysis, scanning electron microscopy analysis and corrosion measurements. Results obtained to date indicate a platinum rich alloy has the best tolerance to bromide ion poisoning.

  8. Pyridostigmine in the treatment of orthostatic intolerance.

    PubMed

    Gales, Barry J; Gales, Mark A

    2007-02-01

    To review the efficacy of pyridostigmine bromide for the treatment of orthostatic intolerance. MEDLINE and International Pharmaceutical Abstracts were searched (1966-December 2006) using the terms pyridostigmine, acetylcholinesterase inhibitor, orthostatic intolerance, orthostatic hypotension, neurogenic orthostatic hypotension, postural tachycardia syndrome, tachycardia, and orthostatic tachycardia. Pertinent English-language human clinical trials, case reports, and background material were evaluated for safety and efficacy data. The references of reviewed articles were reviewed and used to identify additional sources. Pyridostigmine bromide has been associated with improved baroreceptor sensitivity and presents a novel approach to treatment of orthostatic intolerance. Four single-dose trials and a follow-up survey encompassing a total of 106 patients were identified. One open-label and one placebo-controlled single-dose trial in patients with neurogenic orthostatic hypotension (NOH) found statistically significant improvement in standing diastolic blood pressures (DBP). Absolute improvements in standing DBP were 3.7 and 6.4 mm Hg in the open-label and controlled trials, respectively. Long-term data consist of a single survey of patients receiving open-label pyridostigmine bromide. Twenty-nine percent of patients who initiated maintenance pyridostigmine bromide discontinued therapy. Concomitant NOH medications were taken by 75% of patients, and 85% of patients reported receiving benefit from pyridostigmine bromide. When evaluated for postural tachycardia syndrome, pyridostigmine bromide significantly reduced standing heart rate (10%). Pyridostigmine bromide significantly reduced symptom scores when compared with baseline but not placebo. The majority of patients included in these trials did not have supine hypertension. Single doses of pyridostigmine bromide produced modest but statistically significant improvements in hemodynamic measurements. At this time, long-term data are insufficient to support recommending the routine use of pyridostigmine bromide for treatment of orthostatic intolerance.

  9. Vanadium pentoxide nanoparticles mimic vanadium haloperoxidases and thwart biofilm formation

    NASA Astrophysics Data System (ADS)

    Natalio, Filipe; André, Rute; Hartog, Aloysius F.; Stoll, Brigitte; Jochum, Klaus Peter; Wever, Ron; Tremel, Wolfgang

    2012-08-01

    Marine biofouling--the colonization of small marine microorganisms on surfaces that are directly exposed to seawater, such as ships' hulls--is an expensive problem that is currently without an environmentally compatible solution. Biofouling leads to increased hydrodynamic drag, which, in turn, causes increased fuel consumption and greenhouse gas emissions. Tributyltin-free antifouling coatings and paints based on metal complexes or biocides have been shown to efficiently prevent marine biofouling. However, these materials can damage the environment through metal leaching (for example, of copper and zinc) and bacteria resistance. Here, we show that vanadium pentoxide nanowires act like naturally occurring vanadium haloperoxidases to prevent marine biofouling. In the presence of bromide ions and hydrogen peroxide, the nanowires catalyse the oxidation of bromide ions to hypobromous acid (HOBr). Singlet molecular oxygen (1O2) is formed and this exerts strong antibacterial activity, which prevents marine biofouling without being toxic to marine biota. Vanadium pentoxide nanowires have the potential to be an alternative approach to conventional anti-biofouling agents.

  10. METHYL BROMIDE ALTERNATIVES FOR VINEYARD REPLANT

    USDA-ARS?s Scientific Manuscript database

    Soil fumigation with methyl bromide is needed by grape growers in central California to control soilborne pests. However, use of methyl bromide is banned and soil fumigation with other chemicals subjects to strict regulations to protect human health and air quality. The objective was to determine,...

  11. Methyl bromide: effective pest management tool and environmental threat.

    PubMed

    Thomas, W B

    1996-12-01

    Methyl bromide is used extensively on a global basis as a pesticide against nematodes, weeds, insects, fungi, bacteria, and rodents. As a soil fumigant, it is used in significant quantities in the production of strawberry and tomato, as well as other agriculture commodities. Grain, fresh fruit, forestry products, and other materials are fumigated with methyl bromide to control pest infestations during transport and storage. Structures also are treated with this chemical to control wood-destroying insects and rodents. However, methyl bromide has been identified as a significant ozone-depleting substance, resulting in regulatory actions being taken by the U.S. Environmental Protection Agency and the United Nations Environment Program (Montreal Protocol). The science linking methyl bromide to ozone depletion is strong and was reinforced by the 1994 UNEP Montreal Protocol Science Assessment on Ozone Depletion, which states, "Methyl bromide continues to be viewed as a significant ozone-depleting compound." Identifying efficacious and viable alternatives in the near term is critical.

  12. Effect of Bromide-Hypochlorite Bactericides on Microorganisms1

    PubMed Central

    Shere, Lewis; Kelley, Maurice J.; Richardson, J. Harold

    1962-01-01

    A new principle in compounding stable, granular bactericidal products led to unique combinations of a water-soluble inorganic bromide salt with a hypochlorite-type disinfectant of either inorganic or organic type. Microbiological results are shown for an inorganic bactericide composed of chlorinated trisodium phosphate containing 3.1% “available chlorine” and 2% potassium bromide, and for an organic bactericide formulated from sodium dichloroisocyanurate so as to contain 13.4% “available chlorine” and 8% potassium bromide. Comparison of these products with their nonbromide counterparts are reported for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Streptococcus lactis, Aerobacter aerogenes, and Proteus vulgaris. Test methods employed were the Chambers test, the A.O.A.C. Germicidal and Detergent Sanitizer-Official test, and the Available Chlorine Germicidal Equivalent Concentration test. The minimal killing concentrations for the bromide-hypochlorite bactericides against this variety of organisms were reduced by a factor 2 to 24 times those required for similar hypochlorite-type disinfectants not containing the bromide. PMID:13977149

  13. Selective oxidation of bromide in wastewater brines from hydraulic fracturing.

    PubMed

    Sun, Mei; Lowry, Gregory V; Gregory, Kelvin B

    2013-07-01

    Brines generated from oil and natural gas production, including flowback water and produced water from hydraulic fracturing of shale gas, may contain elevated concentrations of bromide (~1 g/L). Bromide is a broad concern due to the potential for forming brominated disinfection byproducts (DBPs) during drinking water treatment. Conventional treatment processes for bromide removal is costly and not specific. Selective bromide removal is technically challenging due to the presence of other ions in the brine, especially chloride as high as 30-200 g/L. This study evaluates the ability of solid graphite electrodes to selectively oxidize bromide to bromine in flowback water and produced water from a shale gas operation in Southwestern PA. The bromine can then be outgassed from the solution and recovered, as a process well understood in the bromine industry. This study revealed that bromide may be selectively and rapidly removed from oil and gas brines (~10 h(-1) m(-2) for produced water and ~60 h(-1) m(-2) for flowback water). The electrolysis occurs with a current efficiency between 60 and 90%, and the estimated energy cost is ~6 kJ/g Br. These data are similar to those for the chlor-alkali process that is commonly used for chlorine gas and sodium hydroxide production. The results demonstrate that bromide may be selectively removed from oil and gas brines to create an opportunity for environmental protection and resource recovery. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Oxidation of Cr(III)-Fe(III) Mixed-phase Hydroxides by Chlorine: Implications on the Control of Hexavalent Chromium in Drinking Water.

    PubMed

    Chebeir, Michelle; Liu, Haizhou

    2018-05-17

    The occurrence of chromium (Cr) as an inorganic contaminant in drinking water is widely reported. One source of Cr is its accumulation in iron-containing corrosion scales of drinking water distribution systems as Cr(III)-Fe(III) hydroxide, i.e., FexCr(1-x)(OH)3(s), where x represents the Fe(III) molar content and typically varies between 0.25 and 0.75. This study investigated the kinetics of inadvertent hexavalent chromium Cr(VI) formation via the oxidation of FexCr(1-x)(OH)3(s) by chlorine as a residual disinfectant in drinking water, and examined the impacts of Fe(III) content and drinking water chemical parameters including pH, bromide and bicarbonate on the rate of Cr(VI) formation. Data showed that an increase in Fe(III) molar content resulted in a significant decrease in the stoichiometric Cr(VI) yield and the rate of Cr(VI) formation, mainly due to chlorine decay induced by Fe(III) surface sites. An increase in bicarbonate enhanced the rate of Cr(VI) formation, likely due to the formation of Fe(III)-carbonato surface complexes that slowed down the scavenging reaction with chlorine. The presence of bromide significantly accelerated the oxidation of FexCr(1-x)(OH)3(s) by chlorine, resulting from the catalytic effect of bromide acting as an electron shuttle. A higher solution pH between 6 and 8.5 slowed down the oxidation of Cr(III) by chlorine. These findings suggested that the oxidative conversion of chromium-containing iron corrosion products in drinking water distribution systems can lead to the occurrence of Cr(VI) at the tap, and the abundance of iron, and a careful control of pH, bicarbonate and bromide levels can assist the control of Cr(VI) formation.

  15. Stability and Microtox Response of Butenyltin Compounds

    DTIC Science & Technology

    compound was as stable as tributyltin bromide. Stability in seawater, in the absence of ultraviolet (UV) light, was less for both tri-1-butenyltin...bromides necessary to produce a toxic responses were three to six times greater than for tributyltin bromide. Keywords: Marine fouling; Environmental impact statement; Antifouling coatings; Organotin; Reprints.

  16. 76 FR 14320 - Importation of Figs and Pomegranates From Chile Under a Systems Approach

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-16

    ... pomegranates from Chile using mitigation measures other than fumigation with methyl bromide. DATES: We will... with methyl bromide. The Animal and Plant Health Inspection Service (APHIS) also received a request... mitigation measures other than fumigation with methyl bromide. Implementation of this rule will require...

  17. The physicochemical properties of the low-temperature ionic liquid silver bromide-1-butyl-3-methylimidazolium bromide

    NASA Astrophysics Data System (ADS)

    Grishina, E. P.; Ramenskaya, L. M.; Pimenova, A. M.

    2009-11-01

    The physicochemical properties of the low-temperature ionic liquid based on 1-butyl-3-methylimidazolium bromide (BMImBr) and silver bromide were studied. Differential scanning calorimetry, Fourier transform IR spectroscopy, densimetry, viscometry, and conductometry measurements were performed to determine the dependences of the parameters under study on the concentration of AgBr. It was shown that the temperature and concentration behavior of the physicochemical properties of BMImBr-AgBr melts characterized the interaction between the system components with the formation of complex particles.

  18. Emission of methyl bromide from biomass burning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Manoe, S.; Andreae, M.O.

    1994-03-04

    Bromine is, per atom, far more efficient than chlorine in destroying stratospheric ozone, and methyl bromide is the single largest source of stratospheric bromine. The two main previously known sources of this compound are emissions from the ocean and from the compound's use as an agricultural pesticide. Laboratory biomass combustion experiments showed that methyl bromide was emitted in the smoke from various fuels tested. Methyl bromide was also found in smoke plumes from wildfires in savannas, chaparral, and boreal forest. Global emissions of methyl bromide from biomass burning are estimated to be in the range of 10 to 50 gigagramsmore » per year, which is comparable to the amount produced by ocean emission and pesticide use and represents a major contribution ([approximately]30 percent) to the stratospheric bromine budget.« less

  19. Ultraviolet-induced sister chromatid exchanges in V-79 cells with normal and BrdUrd-substituted DNA and the influence of intercalating substances and cysteine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Speit, G.; Mehnert, K.; Wolf, M.

    1982-06-01

    The influence of intercalating substances (proflavine, ethidium bromide) and of an SH compound (L-cysteine) on uv-induced sister chromatid exchanges (SCEs) was investigated in V-79 cells with normal and BrdUrd-substituted DNA. The results are discussed in relation to the primary damages leading to SCE induction produced by uv irradiation. The data indicate that neither the pyrimidine dimers nor DNA single-strand breaks are the primary cause of SCE induction, and that the damages leading to SCEs by uv irradiation differ from those which cause chromosome aberrations.

  20. The effect of silver on the optical, spectral-luminescent, and crystallization properties of bromide photo-thermo-refractive glasses

    NASA Astrophysics Data System (ADS)

    Oreshkina, K. V.; Dubrovin, V. D.; Ignat'ev, A. I.; Nikonorov, N. V.

    2017-10-01

    The effect of silver on the optical, spectral-luminescent, and crystallization properties of bromide photo-thermo-refractive glasses is studied. Multicomponent photosensitive glasses of the Na2O-ZnO-Al2O3-SiO2 system with photosensitizing agents (cerium, antimony, silver) and halogenides (fluorine and bromine) are synthesized. Ultraviolet irradiation and thermal treatment below the glass-transition temperature of the glasses cause the formation of silver molecular clusters, which exhibit luminescence in the visible and infrared regions. UV irradiation and thermal treatment of glasses above the glass-transition temperature lead to the growth of silver nanoparticles with plasmon resonance peak in the region of 420 nm. Further thermal treatment of glasses above the glass-transition temperature shifts the plasmon-resonance maximum by 70 nm to longer wavelengths, which is related to the growth of a crystalline shell consisting of mixed silver and sodium bromides on nanoparticles. This formation of a crystalline phase on colloidal centers results in a local increase in the refractive index of the irradiated region by +Δ n 900 ppm compared to the nonirradiated region. Photo-thermo-refractive glasses with increased silver concentration are promising photosensitive materials for creating holographic optical elements and devices for line narrowing and stabilizing filters, spectral beam combiners, and filters for increasing the spectral brightness of laser diodes. A positive change in the refractive index of Photo-thermo-refractive glasses provides the possibility of recording in them 3D waveguide and integrated-optical structures.

  1. The effects of pyridostigmine bromide and permethrin, alone or in combination, on response acquisition in male and female rats.

    PubMed

    Van Haaren, F; Cody, B; Hoy, J B; Karlix, J L; Schmidt, C J; Tebbett, I R; Wielbo, D

    2000-08-01

    It has been hypothesized that concurrent exposure to pyridostigmine bromide and permethrin may have contributed to the development of neurocognitive symptoms in Gulf War veterans. The present experiment was designed to investigate the effects of pyridostigmine bromide and permethrin alone, or in combination, on the acquisition of a novel response, one measure of normal cognitive functioning. Male and female Sprague-Dawley rats were treated with pyridostigmine bromide (1.5 mg/kg/day, by gavage in a volume of 5 ml/kg) or its vehicle for 7 consecutive days. They then also received an intraperitoneal injection of permethrin (0, 15, or 60 mg/kg) before they were exposed to an experimental session during which they could earn food by pressing a lever in an operant chamber. Serum permethrin levels increased as a function of its dose, and were higher in rats treated with pyridostigmine bromide. Sex differences were observed as permethrin levels were higher in female rats than in male rats following the highest dose. Pyridostigmine bromide delayed response acquisition in male and female rats, and resulted in higher response rates on the inactive lever in female rats than in male rats. Although permethrin levels were higher in subjects treated with pyridostigmine bromide than in those treated with vehicle, there were no differences in the behavioral effects of permethrin. Whether or not these behavioral effects of pyridostigmine bromide are of central or peripheral origin will need to be determined in future studies, as its effects on motor activity and/or gastro-intestinal motility may have affected response acquisition.

  2. Destruction of methyl bromide sorbed to activated carbon by thiosulfate and electrolysis

    USDA-ARS?s Scientific Manuscript database

    Methyl bromide is widely used as a fumigant for post-harvest and quarantine uses at port facilities due to the low treatment times required, but it is vented to the atmosphere after its use. Due to the potential contributions of methyl bromide to stratospheric ozone depletion, technologies for the c...

  3. Solid phase microextraction for active or passive sampling of methyl bromide during fumigations

    USDA-ARS?s Scientific Manuscript database

    The high diffusivity and volatility of methyl bromide make it an ideal compound for Solid Phase Micro Extraction (SPME)-based sampling of air prior to gas-chromatographic quantifications. SPME fibers can be used as active methyl bromide samplers, with high capacities and an equilibrium time of 1-2 m...

  4. 77 FR 59709 - Citrus Greening and Asian Citrus Psyllid; Quarantine and Interstate Movement Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... area quarantined only for ACP, if, among other conditions, the article was treated with methyl bromide... application, followed by an APHIS-approved foliar spray; with methyl bromide; or with irradiation. We intended... fumigated with methyl bromide, it did not authorize nursery stock to be treated with irradiation. We are...

  5. 76 FR 15225 - Importation of Fresh Baby Kiwi From Chile Under a Systems Approach

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-21

    ... fumigation with methyl bromide. DATES: We will consider all comments that we receive on or before May 20... fumigated with methyl bromide. The Animal and Plant Health Inspection Service (APHIS) also received a.... The systems approach would provide an alternative to fumigation with methyl bromide of baby kiwi...

  6. 77 FR 12437 - Importation of Wooden Handicrafts From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ... Regarding Treatment With Methyl Bromide In proposed Sec. 319.40-5(o)(1)(ii), we stated that wooden handicrafts that are less than 6 inches in diameter may be treated with methyl bromide fumigation in... caused by methyl bromide emissions. However, paragraph 5 of Article 2H of the Montreal Protocol does...

  7. 76 FR 65933 - Importation of Fresh Baby Kiwi From Chile Under a Systems Approach

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-25

    ... other than fumigation with methyl bromide. DATES: Effective Date: November 25, 2011. FOR FURTHER... allowed only if the fruit was fumigated with methyl bromide. On March 21, 2011, however, we published in... alternative to fumigation with methyl bromide of baby kiwi imported from Chile into the continental United...

  8. An Ill Wind: Methyl Bromide Use Near California Schools, 1998.

    ERIC Educational Resources Information Center

    Ross, Zev; Walker, Bill

    A California study investigates the use of the toxic pesticide methyl bromide near the state's public schools, explains why proposed safety rules have failed to protect children and others from exposure, and examines regions at particular exposure risk. Study results show an increasing exposure to methyl bromide near schools already at risk while…

  9. Comparison of the efficacy of preservative free ipratropium bromide and Atrovent nebuliser solution.

    PubMed Central

    Rafferty, P; Beasley, R; Holgate, S T

    1988-01-01

    The paradoxical bronchoconstriction observed with commercially available isotonic ipratropium bromide nebuliser solution (Atrovent) in patients with asthma results from an adverse reaction to the preservatives, benzalkonium chloride and ethylenediaminetetra-acetic acid (EDTA). The airway response to inhaled Atrovent and preservative free ipratropium bromide nebuliser solutions has been examined in a double blind study. On separate occasions 30 asthmatic subjects inhaled 2 ml of the solutions and airway calibre was measured in terms of FEV1 for 45 minutes. Atrovent nebuliser solution provoked a greater than 20% fall in FEV1 in five of the 30 subjects, whereas this did not occur after preservative free ipratropium bromide. Inhalation of the preservative free solution resulted in more rapid and greater overall bronchodilatation than Atrovent, with mean maximum increases in FEV1 of 29.2% and 18.5% respectively. It is concluded that the risk of paradoxical bronchoconstriction with ipratropium bromide is considerably reduced by removal of benzalkonium chloride and EDTA and that preservative free ipratropium bromide is a more potent bronchodilator than the currently available Atrovent solution. PMID:2971274

  10. Detection of water contamination from hydraulic fracturing wastewater: a μPAD for bromide analysis in natural waters.

    PubMed

    Loh, Leslie J; Bandara, Gayan C; Weber, Genevieve L; Remcho, Vincent T

    2015-08-21

    Due to the rapid expansion in hydraulic fracturing (fracking), there is a need for robust, portable and specific water analysis techniques. Early detection of contamination is crucial for the prevention of lasting environmental damage. Bromide can potentially function as an early indicator of water contamination by fracking waste, because there is a high concentration of bromide ions in fracking wastewaters. To facilitate this, a microfluidic paper-based analytical device (μPAD) has been developed and optimized for the quantitative colorimetric detection of bromide in water using a smartphone. A paper microfluidic platform offers the advantages of inexpensive fabrication, elimination of unstable wet reagents, portability and high adaptability for widespread distribution. These features make this assay an attractive option for a new field test for on-site determination of bromide.

  11. Pyridostigmine bromide versus fludrocortisone in the treatment of orthostatic hypotension in Parkinson's disease - a randomized controlled trial.

    PubMed

    Schreglmann, S R; Büchele, F; Sommerauer, M; Epprecht, L; Kägi, G; Hägele-Link, S; Götze, O; Zimmerli, L; Waldvogel, D; Baumann, C R

    2017-04-01

    Evidence for effective treatment options for orthostatic hypotension (OH) in Parkinson's disease (PD) is scarce. Elevation of cholinergic tone with pyridostigmine bromide has been reported as a way to improve blood pressure (bp) regulation in neurogenic hypotension without causing supine hypertension. This was a double-centre, double-blind, randomized, active-control, crossover, phase II non-inferiority trial of pyridostigmine bromide for OH in PD (clinicaltrials.gov NCT01993680). Patients with confirmed OH were randomized to 14 days 3 × 60 mg/day pyridostigmine bromide or 1 × 0.2 mg/day fludrocortisone before crossover. Outcome was measured by peripheral and central bp monitoring during the Schellong manoeuvre and questionnaires. Thirteen participants were enrolled between April 2013 and April 2015 with nine participants completing each trial arm. Repeated measures comparison showed a significant 37% improvement with fludrocortisone for the primary outcome diastolic bp drop on orthostatic challenge (baseline 22.9 ± 13.6 vs. pyridostigmine bromide 22.1 ± 17.0 vs. fludrocortisone 14.0 ± 12.6 mmHg; P = 0.04), whilst pyridostigmine bromide had no effect. Fludrocortisone caused an 11% peripheral systolic supine bp rise (baseline 128.4 ± 12.8 vs. pyridostigmine bromide 130.4 ± 18.3 vs. fludrocortisone 143.2 ± 10.1 mmHg; P = 0.01) but no central mean arterial supine bp rise (baseline 107.2 ± 7.8 vs. pyridostigmine bromide 97.0 ± 12.0 vs. fludrocortisone 107.3 ± 6.3 mmHg; P = 0.047). Subjective OH severity, motor score and quality of life remained unchanged by both study interventions. Pyridostigmine bromide is inferior to fludrocortisone in the treatment of OH in PD. This trial provides first objective evidence of the efficacy of 0.2 mg/day fludrocortisone for OH in PD, causing minor peripheral but no central supine hypertension. In addition to peripheral bp, future trials should include central bp measurements, known to correlate more closely with cardiovascular risk. © 2017 EAN.

  12. Effect of perfluorocarbon (perfluorooctyl bromide) vapor on tidal volume measurement during partial liquid ventilation.

    PubMed

    Davies, Mark W; Dunster, Kimble R

    2002-05-01

    To compare measured tidal volumes with and without perfluorocarbon (perfluorooctyl bromide) vapor, by using tidal volumes in the range suitable for neonates ventilated with partial liquid ventilation. We also aimed to determine the correction factor needed to calculate tidal volumes measured in the presence of perfluorooctyl bromide vapor. Prospective, experimental study. Neonatal research laboratory. Reproducible tidal volumes from 5 to 30 mL were produced with a rodent ventilator and drawn from humidifier chambers immersed in a water bath at 37 degrees C. Control tidal volumes were drawn from a chamber containing oxygen and water vapor, and the perfluorocarbon tidal volumes were drawn from a chamber containing oxygen, water vapor, and perfluorooctyl bromide vapor. Tidal volumes were measured by a VenTrak respiratory mechanics monitor with a neonatal flow sensor and a Dräger pneumotachometer attached to a Dräger neonatal ventilator. All tidal volumes measured with perfluorooctyl bromide vapor were increased compared with control. The VenTrak-measured tidal volumes increased by 1.8% to 3.5% (an overall increase of 2.2%). The increase was greater with the Dräger hot-wire anemometer: from 2.4% to 6.1% (an overall increase of 5.9%). Regression equations for mean control tidal volumes (response, Y) vs. mean perfluorooctyl bromide tidal volumes (predictor, X) are as follows: for the VenTrak, Y = -0.026 + (0.978 x X), r =.9999, p <.0001; and for the Dräger, Y = 0.251 + (0.944 x X), r =.9996, p <.0001. The presence of perfluorooctyl bromide vapor in the gas flowing through pneumotachometers gives falsely high tidal volume measurements. An estimate of the true tidal volume allowing for the presence of perfluorooctyl bromide vapor can be made from regression equations. Any calculation of lung mechanics must take into account the effect of perfluorooctyl bromide vapor on the measurement of tidal volume.

  13. Nitrate turnover in a peat soil under drained and rewetted conditions: results from a [(15)N]nitrate-bromide double-tracer study.

    PubMed

    Russow, Rolf; Tauchnitz, Nadine; Spott, Oliver; Mothes, Sibylle; Bernsdorf, Sabine; Meissner, Ralph

    2013-01-01

    Under natural conditions, peatlands are generally nitrate-limited. However, recent concerns about an additional N input into peatlands by atmospheric N deposition have highlighted the risk of an increased denitrification activity and hence the likelihood of a rise of emissions of the greenhouse gas nitrous oxide. Therefore, the aim of the present study was to investigate the turnover of added nitrate in a drained and a rewetted peatland using a [(15)N]nitrate-bromide double-tracer method. The double-tracer method allows a separation between physical effects (dilution, dispersion and dislocation) and microbial and chemical nitrate transformation by comparing with the conservative Br(-) tracer. In the drained peat site, low NO3(-) consumption rates have been observed. In contrast, NO3(-) consumption at the rewetted peat site rises rapidly to about 100% within 4 days after tracer application. Concomitantly, the (15)N abundances of nitrite and ammonium in soil water increased and lead to the conclusion that, besides commonly known NO3(-) reduction to nitrite (i.e. denitrification), a dissimilatory nitrate reduction to ammonium has simultaneously taken place. The present study reveals that increasing NO3(-) inputs into rewetted peatlands via atmospheric deposition results in a rapid NO3(-) consumption, which could lead to an increase in N2O emissions into the atmosphere.

  14. Field results of antifouling techniques for optical instruments

    USGS Publications Warehouse

    Strahle, W.J.; Hotchkiss, F.S.; Martini, Marinna A.

    1998-01-01

    An anti-fouling technique is developed for the protection of optical instruments from biofouling which leaches a bromide compound into a sample chamber and pumps new water into the chamber prior to measurement. The primary advantage of using bromide is that it is less toxic than the metal-based antifoulants. The drawback of the bromide technique is also discussed.

  15. Ease of intubation: A randomized, double-blind study to compare two doses of rocuronium bromide for endotracheal intubation.

    PubMed

    Shukla, Aparna; Misra, Shilpi

    2016-01-01

    Clinical need for a nondepolarizing agent with a rapid onset time and a brief duration of action has led to the development of rocuronium bromide. The aim of this study was to evaluate optimal dose of rocuronium bromide for intubation and to compare the onset time, duration of action, intubating conditions, and hemodynamic effects of two doses of rocuronium bromide. A prospective, randomized, double-blind study. All the patients were divided in a randomized, double-blind fashion into two groups of twenty patients each. Group I patients received rocuronium bromide 0.6 mg/kg intravenously and intubated at 60 s, Group II patients received rocuronium bromide 0.9 mg/kg and intubated at 60 s. The neuromuscular block was assessed using single twitch stimulation of 0.1 Hz at adductor pollicis muscle of hand at every 10 s. The results were compiled and analyzed statistically using Chi-square test for qualitative data and Student's t -test for quantitative data. Time of onset was significantly shorter ( P < 0.01) and duration of action was prolonged ( P < 0.001) for Group II as compared to Group I. The intubating conditions were (excellent + good) in 100% patients of Group II and (excellent + good) in 80% of Group I. There was no significant change in pulse rate and mean arterial pressure from the baseline value after the administration of muscle relaxants in either of the two groups. Rocuronium bromide 0.9 mg/kg is a safer alternative to rocuronium bromide 0.6 mg/kg for endotracheal intubation with shorter time of onset and better intubating conditions.

  16. Examining the interrelationship between DOC, bromide and chlorine dose on DBP formation in drinking water--a case study.

    PubMed

    Bond, Tom; Huang, Jin; Graham, Nigel J D; Templeton, Michael R

    2014-02-01

    During drinking water treatment aqueous chlorine and bromine compete to react with natural organic matter (NOM). Among the products of these reactions are potentially harmful halogenated disinfection by-products, notably four trihalomethanes (THM4) and nine haloacetic acids (HAAs). Previous research has concentrated on the role of bromide in chlorination reactions under conditions of a given NOM type and/or concentration. In this study different concentrations of dissolved organic carbon (DOC) from U.K. lowland water were reacted with varying amounts of bromide and chlorine in order to examine the interrelationship between the three reactants in the formation of THM4, dihaloacetic acids (DHAAs) and trihaloacetic acids (THAAs). Results showed that, in general, molar yields of THM4 increased with DOC, bromide and chlorine concentrations, although yields did fluctuate versus chlorine dose. In contrast both DHAA and THAA yields were mainly independent of changes in bromide and chlorine dose at low DOC (1 mg·L(-1)), but increased with chlorine dose at higher DOC concentrations (4 mg·L(-1)). Bromine substitution factors reached maxima of 0.80, 0.67 and 0.65 for the THM4, DHAAs and THAAs, respectively, at the highest bromide/chlorine ratio studied. These results suggest that THM4 formation kinetics depend on both oxidation and halogenation steps, whereas for DHAAs and THAAs oxidation steps are more important. Furthermore, they indicate that high bromide waters may prove more problematic for water utilities with respect to THM4 formation than for THAAs or DHAAs. While mass concentrations of all three groups increased in response to increased bromide incorporation, only the THMs also showed an increase in molar yield. Overall, the formation behaviour of DHAA and THAA was more similar than that of THM4 and THAA. © 2013.

  17. Residential proximity to methyl bromide use and birth outcomes in an agricultural population in California.

    PubMed

    Gemmill, Alison; Gunier, Robert B; Bradman, Asa; Eskenazi, Brenda; Harley, Kim G

    2013-06-01

    Methyl bromide, a fungicide often used in strawberry cultivation, is of concern for residents who live near agricultural applications because of its toxicity and potential for drift. Little is known about the effects of methyl bromide exposure during pregnancy. We investigated the relationship between residential proximity to methyl bromide use and birth outcomes. Participants were from the CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas) study (n = 442), a longitudinal cohort study examining the health effects of environmental exposures on pregnant women and their children in an agricultural community in northern California. Using data from the California Pesticide Use Reporting system, we employed a geographic information system to estimate the amount of methyl bromide applied within 5 km of a woman's residence during pregnancy. Multiple linear regression models were used to estimate associations between trimester-specific proximity to use and birth weight, length, head circumference, and gestational age. High methyl bromide use (vs. no use) within 5 km of the home during the second trimester was negatively associated with birth weight (β = -113.1 g; CI: -218.1, -8.1), birth length (β = -0.85 cm; CI: -1.44, -0.27), and head circumference (β = -0.33 cm; CI: -0.67, 0.01). These outcomes were also associated with moderate methyl bromide use during the second trimester. Negative associations with fetal growth parameters were stronger when larger (5 km and 8 km) versus smaller (1 km and 3 km) buffer zones were used to estimate exposure. Residential proximity to methyl bromide use during the second trimester was associated with markers of restricted fetal growth in our study.

  18. A laboratory study of colloid and solute transport in surface runoff on saturated soil

    NASA Astrophysics Data System (ADS)

    Yu, Congrong; Gao, Bin; Muñoz-Carpena, Rafael; Tian, Yuan; Wu, Lei; Perez-Ovilla, Oscar

    2011-05-01

    SummaryColloids in surface runoff may pose risks to the ecosystems not only because some of them (e.g., pathogens) are toxic, but also because they may facilitate the transport of other contaminants. Although many studies have been conducted to explore colloid fate and transport in the environment, current understanding of colloids in surface runoff is still limited. In this study, we conducted a range of laboratory experiments to examine the transport behavior of colloids in a surface runoff system, made of a soil box packed with quartz sand with four soil drainage outlets and one surface flow outlet. A natural clay colloid (kaolinite) and a conservative chemical tracer (bromide) were applied to the system under a simulated rainfall event (64 mm/h). Effluent soil drainage and surface flow samples were collected to determine the breakthrough concentrations of bromide and kaolinite. Under the experimental conditions tested, our results showed that surface runoff dominated the transport processes. As a result, kaolinite and bromide were found more in surface flow than in soil drainage. Comparisons between the breakthrough concentrations of bromide and kaolinite showed that kaolinite had lower mobility than bromide in the subsurface flow (i.e., soil drainage), but behaved almost identical to bromide in the surface runoff. Student's t-test confirmed the difference between kaolinite and bromide in subsurface flow ( p = 0.02). Spearman's test and linear regression analysis, however, showed a strong 1:1 correlation between kaolinite and bromide in surface runoff ( p < 0.0001). Our result indicate that colloids and chemical solutes may behave similarly in overland flow on bare soils with limited drainage when surface runoff dominates the transport processes.

  19. Methyl bromide as a microbicidal fumigant for tree nuts.

    PubMed Central

    Schade, J E; King, A D

    1977-01-01

    Methyl bromide (MeBr) has broad microbicidal activity, but its use as a disinfectant for food is limited by the resulting bromide residues. Increasing the MeBr concentration, exposure temperature, or exposure period of a treatment tended to increase both the microbicidal efficacy of MeBr and the bromide residues. Its sporicidal activity was less at high than at low relative humidity within the range of 20 to 99%. Both the efficacy and the resulting residues of a MeBr treatment varied inversely with the load of product in a fumigation chamber due to sorption of the fumigant. Fumigation tests with almond kernels inoculated with Escherichia coli or Salmonella typhimurium indicated that MeBr can be used to disinfect whole nut kernels without resulting in excessive bromide residues, although the MeBr level necessary is higher than that normally used for insect control. PMID:406844

  20. 40 CFR 180.123a - Inorganic bromide residues in peanut hay and peanut hulls; statement of policy.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Inorganic bromide residues in peanut hay and peanut hulls; statement of policy. 180.123a Section 180.123a Protection of Environment... RESIDUES IN FOOD Specific Tolerances § 180.123a Inorganic bromide residues in peanut hay and peanut hulls...

  1. Pyridostigmine bromide protection against acetylcholinesterase inhibition by pesticides.

    PubMed

    Henderson, John D; Glucksman, Gabriela; Leong, Bryan; Tigyi, Andras; Ankirskaia, Anna; Siddique, Imteaz; Lam, Helen; DePeters, Ed; Wilson, Barry W

    2012-01-01

    Pyridostigmine bromide (PB) has been used to protect soldiers from the toxic effects of soman, a chemical warfare agent. Recent research shows that pyridostigmine bromide protects a significant percentage of acetylcholinesterase in isolated human intercostal muscle. Findings presented here indicate that red blood cell acetylcholinesterase is similarly protected by pyridostigmine bromide from the action of diisopropyl fluorophosphate and several organophosphate pesticides including chlorpyrifos-oxon, diazinon-oxon, and paraoxon, but not malaoxon, using the bovine red blood cell as a subject. These findings suggest that pretreatment with PB may protect growers, farmworkers, first responders, and the public, in general, from the effects of selected pesticides. Copyright © 2011 Wiley Periodicals, Inc.

  2. Mepenzolate bromide promotes diabetic wound healing by modulating inflammation and oxidative stress

    PubMed Central

    Zheng, Yongjun; Wang, Xingtong; Ji, Shizhao; Tian, Song; Wu, Haibin; Luo, Pengfei; Fang, He; Wang, Li; Wu, Guosheng; Xiao, Shichu; Xia, Zhaofan

    2016-01-01

    Diabetic wounds are characterized by persistent inflammation and the excessive production of reactive oxygen species, thus resulting in impaired wound healing. Mepenzolate bromide, which was originally used to treat gastrointestinal disorders in clinical settings, has recently been shown to display beneficial effects in chronic obstructive pulmonary disease and pulmonary fibrosis of a mouse model by inhibiting inflammatory responses and reducing oxidative stress. However,the role of mepenzolate bromide in diabetic wound healing is still unclear. In this study, full-thickness excisional skin wounds were created on the backs of db/db mice, and mepenzolate bromide was topically applied to the wound bed. We found that mepenzolate bromide significantly promoted diabetic wound healing by measuring wound closure rate and histomorphometric analyses. Further studies showed that inflammation was inhibited by assessing the number of macrophages and levels of pro-inflammatory cytokines and pro-healing cytokines in the wounds. Furthermore, oxidative stress was reduced by monitoring the levels of MDA and H2O2 and the activities of glutathione peroxidase and catalase in the wounds. These results demonstrated the potential application of mepenzolate bromide for treating diabetic ulcers and other chronic wounds in clinics. PMID:27398156

  3. Study on influence of growth conditions on position and shape of crystal/melt interface of alkali lead halide crystals at Bridgman growth

    NASA Astrophysics Data System (ADS)

    Král, Robert

    2012-12-01

    Suitable conditions for growth of high quality single crystals of ternary alkali lead halides prepared by a Bridgman method were explored using direct observation of a crystal/melt interface when pulling an ampoule out of a furnace, deliberated striations' induction and measurement of a temperature field in the filled ampoule in the vertical Bridgman arrangement, as model compounds lead chloride and ternary rubidium lead bromide were used. By direct observation only position of the crystal/melt interface was markedly determined, while by induced striations both the position and the shape of the interface were visualized but their contrast had to be intensified by adding admixtures. Performed temperature measurements in the filled ampoule brought both a view of temperature field in the 3D radial symmetry and basic data for comparison of a real temperature field with those obtained by projected modeling.

  4. Results from service tests on AI-91 gasoline

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turovskii, F.V.; Bakaleinik, A.M.; Belyaev, A.A.

    1988-01-01

    Research was conducted to establish whether the operational reliability of engines will be affected by the use of a gasoline with an octane number two points lower than that of commercial AI-93 leaded gasoline with knock resistance in acceleration that is better than that of the AI-93 by approximately the same amount. Extended road tests were run in VAZ-2106 and Moskvich-2140 automobiles using gasoline with a research octane number of 91, containing an antiknock additive based on tetramethyl lead, and AI-93. The experimental AI-91 and the commercial AI-93 gasolines were prepared from the same base blend. Average specific fuel consumptionsmore » were identical for automobiles using AI-93 and AI-91 with the tetramethyl lead additive. For automobiles using AI-91 with the additive and with ethyl bromide as a lead scavenger the fuel consumption was 2% lower.« less

  5. Catalysis of the Oligomerization of O-Phospho-Serine, Aspartic Acid, or Glutamic Acid by Cationic Micelles

    NASA Technical Reports Server (NTRS)

    Bohler, Christof; Hill, Aubrey R., Jr.; Orgel, Leslie E.

    1996-01-01

    Treatment of relatively concentrated aqueous solutions of 0-phospho-serine (50 mM), aspartic acid (100 mM) or glutamic acid (100 mM) with carbonyldiimidazole leads to the formation of an activated intermediate that oligomerizes efficiently. When the concentration of amino acid is reduced tenfold, few long oligomers can be detected. Positively-charged cetyltrimethyl ammonium bromide micelles concentrate the negatively-charged activated intermediates of the amino acids at their surfaces and catalyze efficient oligomerization even from dilute solutions.

  6. Catalysis of the Oligomerization of O-Phospho-Serine, Aspartic Acid, or Glutamic Acid by Cationic Micelles

    NASA Technical Reports Server (NTRS)

    Boehler, Christof; Hill, Aubrey R., Jr.; Orgel, Leslie E.

    1996-01-01

    Treatment of relatively concentrated aqueous solutions of O-phospho-serine (50 mM), aspartic acid (100 mM) or glutamic acid (100 mM) with carbonyldiimidazole leads to the formation of an activated intermediate that oligomerizes efficiently. When the concentration of amino acid is reduced tenfold, few long oligomers can be detected. Positively-charged cetyltrimethyl ammonium bromide micelles concentrate the negatively-charged activated intermediates of the amino acids at their surfaces and catalyze efficient oligomerization even from dilute solutions.

  7. Stabilized thallium bromide radiation detectors and methods of making the same

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leao, Cedric Rocha; Lordi, Vincenzo

    According to one embodiment, a crystal includes thallium bromide (TlBr), one or more positively charged dopants, and one or more negatively charged dopants. According to another embodiment, a system includes a monolithic crystal including thallium bromide (TlBr), one or more positively charged dopants, and one or more negatively charged dopants; and a detector configured to detect a signal response of the crystal.

  8. 49 CFR 173.193 - Bromoacetone, methyl bromide, chloropicrin and methyl bromide or methyl chloride mixtures, etc.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... packaged as follows in wooden boxes (4C1, 4C2, 4D or 4F) with inner glass receptacles or tubes in... material. Total amount of liquid in the outer box must not exceed 11 kg (24 pounds). Packagings must... bromide mixtures containing up to 2% chloropicrin must be packaged in 4G fiberboard boxes with inside...

  9. 49 CFR 173.193 - Bromoacetone, methyl bromide, chloropicrin and methyl bromide or methyl chloride mixtures, etc.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... packaged as follows in wooden boxes (4C1, 4C2, 4D or 4F) with inner glass receptacles or tubes in... material. Total amount of liquid in the outer box must not exceed 11 kg (24 pounds). Packagings must... bromide mixtures containing up to 2% chloropicrin must be packaged in 4G fiberboard boxes with inside...

  10. Assessing the occurrence of the dibromide radical (Br₂⁻•) in natural waters: measures of triplet-sensitised formation, reactivity, and modelling.

    PubMed

    De Laurentiis, Elisa; Minella, Marco; Maurino, Valter; Minero, Claudio; Mailhot, Gilles; Sarakha, Mohamed; Brigante, Marcello; Vione, Davide

    2012-11-15

    The triplet state of anthraquinone-2-sulphonate (AQ2S) is able to oxidise bromide to Br(•)/Br(2)(-•), with rate constant (2-4)⋅10(9)M(-1)s(-1) that depends on the pH. Similar processes are expected to take place between bromide and the triplet states of naturally occurring chromophoric dissolved organic matter ((3)CDOM*). The brominating agent Br(2)(-•) could thus be formed in natural waters upon oxidation of bromide by both (•)OH and (3)CDOM*. Br(2)(-•) would be consumed by disproportionation into bromide and bromine, as well as upon reaction with nitrite and most notably with dissolved organic matter (DOM). By using the laser flash photolysis technique, and phenol as model organic molecule, a second-order reaction rate constant of ~3⋅10(2)L(mg C)(-1)s(-1) was measured between Br(2)(-•) and DOM. It was thus possible to model the formation and reactivity of Br(2)(-•) in natural waters, assessing the steady-state [Br(2)(-•)]≈10(-13)-10(-12)M. It is concluded that bromide oxidation by (3)CDOM* would be significant compared to oxidation by (•)OH. The (3)CDOM*-mediated process would prevail in DOM-rich and bromide-rich environments, the latter because elevated bromide would completely scavenge (•)OH. Under such conditions, (•)OH-assisted formation of Br(2)(-•) would be limited by the formation rate of the hydroxyl radical. In contrast, the formation rate of (3)CDOM* is much higher compared to that of (•)OH in most surface waters and would provide a large (3)CDOM* reservoir for bromide to react with. A further issue is that nitrite oxidation by Br(2)(-•) could be an important source of the nitrating agent (•)NO(2) in bromide-rich, nitrite-rich and DOM-poor environments. Such a process could possibly account for significant aromatic photonitration observed in irradiated seawater and in sunlit brackish lagoons. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Low-Dimensional Organic Tin Bromide Perovskites and Their Photoinduced Structural Transformation.

    PubMed

    Zhou, Chenkun; Tian, Yu; Wang, Mingchao; Rose, Alyssa; Besara, Tiglet; Doyle, Nicholas K; Yuan, Zhao; Wang, Jamie C; Clark, Ronald; Hu, Yanyan; Siegrist, Theo; Lin, Shangchao; Ma, Biwu

    2017-07-24

    Hybrid organic-inorganic metal halide perovskites possess exceptional structural tunability, with three- (3D), two- (2D), one- (1D), and zero-dimensional (0D) structures on the molecular level all possible. While remarkable progress has been realized in perovskite research in recent years, the focus has been mainly on 3D and 2D structures, with 1D and 0D structures significantly underexplored. The synthesis and characterization of a series of low-dimensional organic tin bromide perovskites with 1D and 0D structures is reported. Using the same organic and inorganic components, but at different ratios and reaction conditions, both 1D (C 4 N 2 H 14 )SnBr 4 and 0D (C 4 N 2 H 14 Br) 4 SnBr 6 can be prepared in high yields. Moreover, photoinduced structural transformation from 1D to 0D was investigated experimentally and theoretically in which photodissociation of 1D metal halide chains followed by structural reorganization leads to the formation of a more thermodynamically stable 0D structure. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Formation of Long-Lived Color Centers for Broadband Visible Light Emission in Low-Dimensional Layered Perovskites.

    PubMed

    Booker, Edward P; Thomas, Tudor H; Quarti, Claudio; Stanton, Michael R; Dashwood, Cameron D; Gillett, Alexander J; Richter, Johannes M; Pearson, Andrew J; Davis, Nathaniel J L K; Sirringhaus, Henning; Price, Michael B; Greenham, Neil C; Beljonne, David; Dutton, Siân E; Deschler, Felix

    2017-12-27

    We investigate the origin of the broadband visible emission in layered hybrid lead-halide perovskites and its connection with structural and photophysical properties. We study ⟨001⟩ oriented thin films of hexylammonium (HA) lead iodide, (C 6 H 16 N) 2 PbI 4 , and dodecylammonium (DA) lead iodide, (C 12 H 28 N) 2 PbI 4 , by combining first-principles simulations with time-resolved photoluminescence, steady-state absorption and X-ray diffraction measurements on cooling from 300 to 4 K. Ultrafast transient absorption and photoluminescence measurements are used to track the formation and recombination of emissive states. In addition to the excitonic photoluminescence near the absorption edge, we find a red-shifted, broadband (full-width at half-maximum of about 0.4 eV), emission band below 200 K, similar to emission from ⟨110⟩ oriented bromide 2D perovskites at room temperature. The lifetime of this sub-band-gap emission exceeds that of the excitonic transition by orders of magnitude. We use X-ray diffraction measurements to study the changes in crystal lattice with temperature. We report changes in the octahedral tilt and lattice spacing in both materials, together with a phase change around 200 K in DA 2 PbI 4 . DFT simulations of the HA 2 PbI 4 crystal structure indicate that the low-energy emission is due to interstitial iodide and related Frenkel defects. Our results demonstrate that white-light emission is not limited to ⟨110⟩ oriented bromide 2D perovskites but a general property of this class of system, and highlight the importance of defect control for the formation of low-energy emissive sites, which can provide a pathway to design tailored white-light emitters.

  13. Applying Genomic and Genetic Tools to Understand and Mitigate Damage from Exposure to Toxins

    DTIC Science & Technology

    2011-10-01

    Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Use of the pyridostigmine bromide during the 1991 Gulf War has been implicated as a contributing...2 EXECUTIVE SUMMARY Treatment of soldiers of the 1991 Gulf War with the drug pyridostigmine bromide for pretreatment against nerve agents has...organism for the characterization of the effects of pyridostigmine bromide (PB) on gene expression using unbiased, high-throughput techniques, specifically

  14. Circadian Rhythms of Heart Rate and Locomotion After Treatment With Low-Dose Acetylcholinesterase Inhibitors

    DTIC Science & Technology

    2006-01-01

    with pyridostigmine bromide (PB), a carbamate AChE by air conditioned vans and air-freight to the Laboratory inhibitor that does not cross the blood ...15. SUBJECT TERMS Nerve agents, sarin, pyridostigmine bromide, cerebral glucose utilization, cerebrovascular circulation, low dose cholinesterase ...March 2006" Accepted 12 May 2006 ABSTRACT: This study tested the hypothesis that repeated exposure to low levels of sarin, pyridostigmine bromide (PB

  15. Dual role of allylsamarium bromide as a Grignard reagent and a single electron transfer reagent in the one-pot synthesis of terminal olefins.

    PubMed

    Li, Ying; Hu, Yuan-Yuan; Zhang, Song-Lin

    2013-11-21

    The utility of allylsamarium bromide, both as a nucleophilic reagent and a single-electron transfer reagent, in the reaction of carbonyl compounds with allylsamarium bromide in the presence of diethyl phosphate is reported in this communication. From a synthetic point of view, a simple one-pot method for the preparation of terminal olefins is developed.

  16. Contaminant Mass Transfer During Boiling in Fractured Geologic Media

    DTIC Science & Technology

    2011-04-01

    on GC-ECD. Bromide was measured on a Dionex AS50 ion chromatography system equipped with a CD25 conductivity detector and a Dionex guard column...EDB Dibromethane EPICS Equilibrium Partitioning In Closed Systems FID Flame Ionized Detector GC Gas Chromatography IC Ion Chromatography ...International). Bromide was measured from filtered samples with a Dionex ion chromatograph (IC) with an AS11/AG11 column. The eluant for bromide

  17. Synthesis and Mass Spectra of Butenyltin Compounds

    DTIC Science & Technology

    1989-03-01

    activities or operations. One instance of this concern has focused on the Navy’s use of tributyltin compounds as antifoulants on ships’ hulls. Such...butene, and 1-chloro- 2-butene were obtained from Pfaltz & Bauer (Waterbury, CT). Resublimed magne- sium chips, tetrabutyltin and tributyltin bromide...preferential elimination of R minus R to form RSn ’from R3Sn + The fragmentation patterns of tributyltin bromide and tributenyltin bromides are dominated

  18. Determination of bromide in aqueous solutions via the TlBr molecule using high-resolution continuum source graphite furnace molecular absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Cacho, Frantisek; Machynak, Lubomir; Nemecek, Martin; Beinrohr, Ernest

    2018-06-01

    The paper describes the determination of bromide by evaluating the molecular absorption of thallium mono-bromide (TlBr) at the rotational line at 342.9815 nm by making use a high-resolution continuum source graphite furnace atomic absorption spectrometer. The effects of variables such as the wavelength, graphite furnace program, amount of Tl and the use of a modifier were investigated and optimized. Various chemical modifiers have been studied, such as Pd, Mg, Ag and a mixture of Pd/Mg. It was found that best results were obtained by using Ag which prevents losses of bromide during pyrolysis step through precipitation of bromide as AgBr. In this way, a maximum pyrolysis temperature of 400 °C could be used. The optimum molecule forming temperature was found to be 900 °C. Bromide concentrations in various water samples (CRM, bottled drinking water and tap water) were determined. The quantification was made by both linear calibration and standard addition techniques. The results were matched well those of the reference method. The calibration curve was linear in the range between 1 and 1000 ng Br with a correlation coefficient R = 0.999. The limit of detection and characteristic mass of the method were 0.3 ng and 4.4 ng of Br.

  19. Determination of methyl bromide in air samples by headspace gas chromatography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Woodrow, J.E.; McChesney, M.M.; Seiber, J.N.

    1988-03-01

    Methyl bromide is extensively used in agriculture (4 x 10/sup 6/ kg for 1985 in California alone as a fumigant to control nematodes, weeds, and fungi in soil and insect pests in harvested grains and nuts. Given its low boiling point (3.8/sup 0/C) and high vapor pressure (approx. 1400 Torr at 20/sup 0/C), methyl bromide will readily diffuse if not rigorously contained. Methods for determining methyl bromide and other halocarbons in air vary widely. A common practice is to trap the material from air on an adsorbent, such as polymeric resins, followed by thermal desorption either directly into the analyticalmore » instrumentation or after intermediary cryofocusing. While in some cases analytical detection limits were reasonable (parts per million range), many of the published methods were labor intensive and required special handling techniques that precluded high sample throughput. They describe here a method for the sampling and analysis of airborne methyl bromide that was designed to handle large numbers of samples through automating some critical steps of the analysis. The result was a method that allowed around-the-clock operation with a minimum of operator attention. Furthermore, the method was not specific to methyl bromide and could be used to determine other halocarbons in air.« less

  20. The oxidation of reduced nicotinamide nucleotides by hydrogen peroxide in the presence of lactoperoxidase and thiocyanate, iodide or bromide

    PubMed Central

    McC. Hogg, D.; Jago, G. R.

    1970-01-01

    Lactoperoxidase (EC 1.11.1.7) catalysed the oxidation of NADH by hydrogen peroxide in the presence of either thiocyanate, iodide or bromide. In the presence of thiocyanate, net oxidation of thiocyanate occurred simultaneously with the oxidation of NADH, but in the presence of iodide or bromide, only the oxidation of NADH occurred to a significant extent. In the presence of thiocyanate or bromide, NADH was oxidized to NAD+ but in the presence of iodide, an oxidation product with spectral and chemical properties distinct from NAD+ was formed. Thiocyanate, iodide and bromide appeared to function in the oxidation of NADH by themselves being oxidized to products which in turn oxidized NADH, rather than by activating the enzyme. Iodine, which oxidized NADH non-enzymically, appeared to be an intermediate in the oxidation of NADH in the presence of iodide. NADPH was oxidized similarly under the same conditions. An assessment was made of the rates of these oxidation reactions, together with the rates of other lactoperoxidase-catalysed reactions, at physiological concentrations of thiocyanate, iodide and bromide. The results indicated that in milk and saliva the oxidation of thiocyanate to a bacterial inhibitor was likely to predominate over the oxidation of NADH. PMID:4317722

  1. Design, Structure, and Optical Properties of Organic-Inorganic Perovskites Containing an Oligothiophene Chromophore.

    PubMed

    Mitzi, David B.; Chondroudis, Konstantinos; Kagan, Cherie R.

    1999-12-27

    A quaterthiophene derivative, 5,5' "-bis(aminoethyl)-2,2':5',2' ':5' ',2' "-quaterthiophene (AEQT), has been selected for incorporation within the layered organic-inorganic perovskite structure. In addition to having an appropriate molecular shape and two tethering aminoethyl groups to bond to the inorganic framework, AEQT is also a dye and can influence the optical properties of lead(II) halide-based perovskites. Crystals of C(20)H(22)S(4)N(2)PbBr(4) were grown from a slowly cooled aqueous solution containing lead(II) bromide and quaterthiophene derivative (AEQT.2HBr) salts. The new layered perovskite adopts a monoclinic (C2/c) subcell with the lattice parameters a = 39.741(2) Å, b = 5.8420(3) Å, c = 11.5734(6) Å, beta = 92.360(1) degrees, and Z = 4. Broad superstructure peaks are observed in the X-ray diffraction data, indicative of a poorly ordered, doubled supercell along both the a and b axes. The quaterthiophene segment of AEQT(2+) is nearly planar, with a syn-anti-syn relationship between adjacent thiophene rings. Each quaterthiophene chromophore is ordered between nearest-neighbor lead(II) bromide sheets in a herringbone arrangement with respect to neighboring quaterthiophenes. Room temperature optical absorption spectra for thermally ablated films of the perovskites (AEQT)PbX(4) (X = Cl, Br, I) exhibit an exciton peak arising from the lead(II) halide sheets, along with absorption from the quaterthiophene moiety. No evidence of the inorganic sheet excitonic transition is observed in the photoluminescence spectra for any of the chromophore-containing perovskites. However, strong quaterthiophene photoluminescence is observed for X = Cl, with an emission peak at approximately lambda(max) = 532 nm. Similar photoluminescence is observed for the X = Br and I materials, but with substantial quenching, as the inorganic layer band gap decreases relative to the chromophore HOMO-LUMO gap.

  2. Water and Solute Mass Transport in Soils Developed on glacial Drift: A Br Tracer Investigation Using Instrumented Soil Monoliths at an Agricultural Long Term Ecological Research Site (Kellogg Biological Station, Hickory Corners, Southern Michigan)

    NASA Astrophysics Data System (ADS)

    Jin, L.; Hamilton, S. K.; Walter, L. M.

    2004-12-01

    Hydrologic processes control the residence time of water in the soil column. This is of central importance in understanding mineral weathering rates in terms of reaction kinetics and solute transport. In order to better quantify the coupling between water and solute mass transport and to better define controls on carbonate and aluminosilicates weathering rates, we have conducted bromide-tracer introduction experiments at four replicate soil monoliths (4 m3 volume) instrumented and managed by the KBS-LTER. Monolith soils are developed on the pitted outwash plain of the morainic system left by the last retreat of the Wisconsin glaciation, around 12,000 years ago. Soil profiles from the monolith sections extend to 200 cm and they were sampled and characterized texturally and mineralogically. Quartz and feldspar are dominant throughout the soil profile, while carbonates and hornblende occur only in deeper soil horizons. The four replicate monoliths are instrumented with gas and soil water sampling devices (Prenart tension lysimeters) at various depths. The monoliths also have a large capacity tray at the bottom, which permits collection of water for weight and chemical determinations. A bromide tracer solution (as lithium bromide) was applied to coincide as closely as possible with a major snowmelt event (2/27/04). The saturated and unsaturated transport of bromide through the four monoliths was followed as a function of time and soil profile depth for the duration of the snowmelt as well as intermittent rain events. Because the soil was saturated at the time of bromide application, the bromide solution is expected to move rapidly through macropores, followed by slower movement into micropores. The unsaturated transport of bromide is largely controlled by the intensity and duration of the rains if it is dominated by piston flow as opposed to preferential channel flow. In general, the tracer moved through the shallow soils very quickly, which is shown by early sharp peaks in bromide concentrations. Transport of bromide into deeper soil horizons, however, differs markedly among the four monoliths. Even within a given monolith, waters sampled at the same depth by different tension lysimeters show a very different pattern of bromide transport over time with some lyimeters suggesting piston flow, while others in the same monolith suggest preferential channel flow. These differences are likely driven by heterogeneous soil textures. The water recovered from the monolith trays over the first three months of the study period is between 80 and 90 percent of the total precipitation recorded at the LTER site. This recovery is reasonable given the fact that temperature was low and crops were not yet actively growing. The recovery of bromide is different among the monoliths and in general is less than 50 percent, which means more than 50 percent of tracer is still in the soils even after three months. Residence time of water has been calculated after some assumptions on the breakthrough curve. The water mass transport constraints imposed by the bromide tracer study will be utilized in concert with additional data on soil water geochemistry.

  3. Single-Crystal Thin Films of Cesium Lead Bromide Perovskite Epitaxially Grown on Metal Oxide Perovskite (SrTiO 3)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Jie; Morrow, Darien J.; Fu, Yongping

    High-quality metal halide perovskite single crystals have low defect densities and excellent photophysical properties, yet thin films are the most sought after material geometry for optoelectronic devices. Perovskite single-crystal thin films (SCTFs) would be highly desirable for high-performance devices, but their growth remains challenging, particularly for inorganic metal halide perovskites. Herein, we report the facile vapor-phase epitaxial growth of cesium lead bromide perovskite (CsPbBr 3) continuous SCTFs with controllable micrometer thickness, as well as nanoplate arrays, on traditional oxide perovskite SrTiO 3(100) substrates. Heteroepitaxial single-crystal growth is enabled by the serendipitous incommensurate lattice match between these two perovskites, and overcomingmore » the limitation of island-forming Volmer–Weber crystal growth is critical for growing large-area continuous thin films. Time-resolved photoluminescence, transient reflection spectroscopy, and electrical transport measurements show that the CsPbBr 3 epitaxial thin film has a slow charge carrier recombination rate, low surface recombination velocity (10 4 cm s –1), and low defect density of 10 12 cm –3, which are comparable to those of CsPbBr 3 single crystals. This work suggests a general approach using oxide perovskites as substrates for heteroepitaxial growth of halide perovskites. Furthermore, the high-quality halide perovskite SCTFs epitaxially integrated with multifunctional oxide perovskites could open up opportunities for a variety of high-performance optoelectronics devices.« less

  4. Single-Crystal Thin Films of Cesium Lead Bromide Perovskite Epitaxially Grown on Metal Oxide Perovskite (SrTiO 3)

    DOE PAGES

    Chen, Jie; Morrow, Darien J.; Fu, Yongping; ...

    2017-09-05

    High-quality metal halide perovskite single crystals have low defect densities and excellent photophysical properties, yet thin films are the most sought after material geometry for optoelectronic devices. Perovskite single-crystal thin films (SCTFs) would be highly desirable for high-performance devices, but their growth remains challenging, particularly for inorganic metal halide perovskites. Herein, we report the facile vapor-phase epitaxial growth of cesium lead bromide perovskite (CsPbBr 3) continuous SCTFs with controllable micrometer thickness, as well as nanoplate arrays, on traditional oxide perovskite SrTiO 3(100) substrates. Heteroepitaxial single-crystal growth is enabled by the serendipitous incommensurate lattice match between these two perovskites, and overcomingmore » the limitation of island-forming Volmer–Weber crystal growth is critical for growing large-area continuous thin films. Time-resolved photoluminescence, transient reflection spectroscopy, and electrical transport measurements show that the CsPbBr 3 epitaxial thin film has a slow charge carrier recombination rate, low surface recombination velocity (10 4 cm s –1), and low defect density of 10 12 cm –3, which are comparable to those of CsPbBr 3 single crystals. This work suggests a general approach using oxide perovskites as substrates for heteroepitaxial growth of halide perovskites. Furthermore, the high-quality halide perovskite SCTFs epitaxially integrated with multifunctional oxide perovskites could open up opportunities for a variety of high-performance optoelectronics devices.« less

  5. The toxic chemistry of methyl bromide.

    PubMed

    Bulathsinghala, A T; Shaw, I C

    2014-01-01

    Methyl bromide (MeBr) is a chemically reactive compound that has found use as a fire retardant and fumigant used for wood, soil, fruits and grains. Its use is banned in many countries because of its ozone-depleting properties. Despite this ban, the use of MeBr persists in some parts of the world (e.g. New Zealand) due to its important role in maintaining strict biosecurity of exported and imported products. Its high chemical reactivity leads to a broad toxicological profile ranging from acute respiratory toxicity following inhalation exposure, through carcinogenicity to neurotoxicty. In this article, we discuss the chemistry of MeBr in the context of its mechanisms of toxicity. The chemical reactivity of MeBr clearly underlies its toxicity. Bromine (Br) is electronegative and a good leaving group; the δ+ carbon thus facilitates electrophilic methylation of biological molecules including glutathione (GSH) via its δ- sulphur atom, leading to downstream effects due to GSH depletion. DNA alkylation, either directly by MeBr or indirectly due to reduction in GSH-mediated detoxification of reactive alkylating chemical species, might explain the carcinogenicity of MeBr. The neurotoxicity of MeBr is much more difficult to understand, but we speculate that methyl phosphates formed in cells might contribute to its neurone-specific toxicity via cholinesterase inhibition. Finally, evidence reviewed shows that it is unlikely for Br⁻ liberated by the metabolism of MeBr to have any toxicological effect because the Br⁻ dose is very low.

  6. Current Pyridostigmine Bromide and Huperzine A Studies and Future Cholinesterase Screening Using the WRAIR Whole Blood Cholinesterase Assay

    DTIC Science & Technology

    2004-11-15

    1 CURRENT PYRIDOSTIGMINE BROMIDE AND HUPERZINE A STUDIES AND FUTURE CHOLINESTERASE SCREENING USING THE WRAIR WHOLE BLOOD...selective (e.g. Huperzine A ) and non-selective (carbamate) inhibitors (e.g. pyridostigmine bromide, PB). We found that volunteers given pyridostigmine...profile of healthy elderly volunteers receiving Huperzine A . 52.7 ± 1.5% inhibition was observed at the end of an increasing dose regimen (final dose

  7. A comparison between the gastric and salivary concentration of iodide, pertechnetate, and bromide in man

    PubMed Central

    Harden, R. McG.; Alexander, W. D.; Shimmins, J.; Chisholm, D.

    1969-01-01

    The concentration of iodide (I−) and pertechnetate (TcO4−) and bromide (Br−) has been measured simultaneously in gastric juice and parotid saliva. The combined gastric and salivary clearance for iodide and pertechnetate is more than twice the clearance of these ions by the thyroid gland. The concentration of the ions was in the order I−>TcO4−>Br− in both gastric juice and saliva. Differences exist between the secretion of iodide, pertechnetate, and bromide. Bromide, in contrast to iodide and pertechnetate, was found to be more concentrated in gastric juice than in saliva. The ratio of the iodide to pertechnetate clearance was greater in gastric juice than in saliva. PMID:5358585

  8. Effectiveness of methyl bromide as a cargo fumigant for brown treesnakes

    USGS Publications Warehouse

    Savarie, P.J.; Wood, W.S.; Rodda, G.H.; Bruggers, R.L.; Engeman, R.M.

    2005-01-01

    The effectiveness of methyl bromide as a fumigant for brown treesnake (Boiga irregularis) management was evaluated on Guam. Eighteen snakes in secured cloth bags were randomly positioned in a 47.7-m3 tarpaulin-covered cargo container for each fumigation treatment. Methyl bromide treatments tested were: 24 g m−3 and and 12 g m−3, both for 2-h and 1-h exposures. All treatments, except for 12 g m−3 for 1 h, resulted in 100% mortality. Two-hour exposures to methyl bromide at 24 and 12 g m−3 appear to be effective in killing brown treesnakes within reasonable time-frames for shippers under Guam field conditions.

  9. Bromide, Chloride, and Sulfate Concentrations, and Specific Conductance, Lake Texoma, Texas and Oklahoma, 2007-08

    USGS Publications Warehouse

    Baldys, Stanley

    2009-01-01

    The U.S. Geological Survey, in cooperation with the City of Dallas Water Utilities Division, collected water-quality data from 11 sites on Lake Texoma, a reservoir on the Texas-Oklahoma border, during April 2007-September 2008. At 10 of the sites, physical properties (depth, specific conductance, pH, temperature, dissolved oxygen, and alkalinity) were measured and samples were collected for analysis of selected dissolved constituents (bromide, calcium, magnesium, potassium, sodium, carbonate, bicarbonate, chloride, and sulfate); at one site, only physical properties were measured. The primary constituent of interest was bromide. Bromate can form when ozone is used to disinfect raw water containing bromide, and bromate is a suspected human carcinogen. Chloride and sulfate were of secondary interest. Only the analytical results for bromide, chloride, sulfate, and measured specific conductance are discussed in this report. Median dissolved bromide concentrations ranged from 0.28 to 0.60 milligrams per liter. The largest median dissolved bromide concentration (0.60 milligram per liter at site 11) was from the Red River arm of Lake Texoma. Dissolved bromide concentrations generally were larger in the Red River arm of Lake Texoma than in the Washita arm of the lake. Median dissolved chloride concentrations were largest in the Red River arm of Lake Texoma at site 11 (431 milligrams per liter) and smallest at site 8 (122 milligrams per liter) in the Washita arm. At site 11 in the Red River arm, the mean and median chloride concentrations exceeded the secondary maximum contaminant level of 300 milligrams per liter for chloride established by the 'Texas Surface Water Quality Standards' for surface-water bodies designated for the public water supply use. Median dissolved sulfate concentrations ranged from 182 milligrams per liter at site 4 in the Big Mineral arm to 246 milligrams per liter at site 11 in the Red River arm. None of the mean or median sulfate concentrations exceeded the secondary maximum contaminant level of 300 milligrams per liter. Median specific conductance measurements at sites ranged from 1,120 microsiemens per centimeter at site 8 in the Washita arm to 2,100 microsiemens per centimeter in the Red River arm. The spatial distribution of specific conductance in Lake Texoma was similar to that of bromide and chloride, with larger specific conductance values in the Red River arm compared to those in the Washita arm.

  10. Evaluation of propargyl bromide for control of barnyardgrass and Fusarium oxysporum in three soils.

    PubMed

    Ma, Q; Gan, J; Becker, J O; Papiernik, S K; Yates, S R

    2001-09-01

    With the scheduled phasing out of methyl bromide, there is an urgent need for alternatives. We evaluated the efficacy of propargyl bromide as a potential replacement for methyl bromide for the control of barnyardgrass (Echinochloa crus-galli) and Fusarium oxysporum in an Arlington sandy loam, a Carsitas loamy sand and a Florida muck soil. Soil was mixed with barnyardgrass seeds or F oxysporum colonized on millet seeds, and treated with propargyl bromide at a range of concentrations. The mortality of the fungi and weed seeds was determined after 24 h of exposure at 30 degrees C. The concentrations required to inhibit 50% barnyard seed germination (LC50) were 2.8, 2.4 and 48.5 micrograms g-1 in the sandy loam, loamy sand and muck soil, respectively. In contrast, the LC50 values for F oxysporum were 11.2, 10.8 and 182.1 micrograms g-1 in the sandy loam, loamy sand and muck soil, respectively. The low efficacy of propargyl bromide in the muck soil was a result of the rapid degradation and high adsorption of the compound in the soil. The degradation half-life (t1/2) was only 7 h in the muck soil at an initial concentration of 6.8 micrograms g-1, compared to 60 and 67 h in the sandy loam and loamy sand, respectively. The adsorption coefficients (Kd) were 0.96, 0.87 and 5.6 cm3 g-1 in the sandy loam, loamy sand and muck soil, respectively. These results suggest that registration agencies should consider site-specific properties in recommending application rates for propargyl bromide.

  11. Treatment of Memory Impairment and Sensorimotor Deficits in an Animal Model for the Gulf War Veterans Illnesses

    DTIC Science & Technology

    2010-09-01

    B.E. and Khan, W.A., (2001b). Locomotor and sensorimotor performance deficit in rats following exposure to pyridostigmine bromide , DEET, and...Induction of urinary excretion of 3-nitrotyrosine, a m arker of oxidative stress foll owing administration of pyridostigmine bromide , N,N-diethyl-m...Abdel-Rahman, A.A., Bull man, S. L., and Khan, W .A., (2004). Co-exposure to pyridostig mine bromide , DEET and/or perm ethrin causes

  12. Acute Toxicity and Efficacy of Current Medical Countermeasures against VM in Guinea Pigs: A Comparison to VX and VR

    DTIC Science & Technology

    2013-05-01

    and diazepam with and without pretreatment with pyridostigmine bromide . The 24 hr median lethal dose (MLD) of VM was determined using a sequential... pyridostigmine bromide . The 24 hr median lethal dose (MLD) of VM was determined using a sequential stage approach. The efficacy of medical...with and without pyridostigmine bromide (PB) pretreatment against lethal intoxication with VM, VR or VX. Methods Animals: Adult male Hartley

  13. Synthesis and evaluation of new antimalarial analogues of quinoline alkaloids derived from Cinchona ledgeriana Moens ex Trimen.

    PubMed

    Park, Byeoung-Soo; Kim, Dae-Young; Rosenthal, Philip J; Huh, Sun-Chul; Lee, Belinda J; Park, Eun -u; Kim, Sung-Min; Kim, Jang-Eok; Kim, Mi-Hee; Huh, Tae-Lin; Choi, Young-Jae; Suh, Ki-Hyung; Choi, Won-Sik; Lee, Sung-Eun

    2002-05-20

    In the course of attempts to develop antimalarial drugs, we have designed and synthesized a series of quinoline alkaloide derivatives. Three of them, N-(4-methoxy-3,5-di-tert-butylbenzyl)cinchonidinium bromide (OSL-5), O-benzyl-N-(3,5-di-tert-butyl-4-methoxybenzyl)cinchonidinium bromide (OSL-7), and N-(3,5-di-tert-butyl-4-methoxybenzyl)quininium bromide (OSL-14) show potent activity against Plasmodium falciparum.

  14. Simultaneous removal of dissolved organic matter and bromide from drinking water source by anion exchange resins for controlling disinfection by-products.

    PubMed

    Phetrak, Athit; Lohwacharin, Jenyuk; Sakai, Hiroshi; Murakami, Michio; Oguma, Kumiko; Takizawa, Satoshi

    2014-06-01

    Anion exchange resins (AERs) with different properties were evaluated for their ability to remove dissolved organic matter (DOM) and bromide, and to reduce disinfection by-product (DBP) formation potentials of water collected from a eutrophic surface water source in Japan. DOM and bromide were simultaneously removed by all selected AERs in batch adsorption experiments. A polyacrylic magnetic ion exchange resin (MIEX®) showed faster dissolved organic carbon (DOC) removal than other AERs because it had the smallest resin bead size. Aromatic DOM fractions with molecular weight larger than 1600 Da and fluorescent organic fractions of fulvic acid- and humic acid-like compounds were efficiently removed by all AERs. Polystyrene AERs were more effective in bromide removal than polyacrylic AERs. This result implied that the properties of AERs, i.e. material and resin size, influenced not only DOM removal but also bromide removal efficiency. MIEX® showed significant chlorinated DBP removal because it had the highest DOC removal within 30 min, whereas polystyrene AERs efficiently removed brominated DBPs, especially brominated trihalomethane species. The results suggested that, depending on source water DOM and bromide concentration, selecting a suitable AER is a key factor in effective control of chlorinated and brominated DBPs in drinking water. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  15. Large-scale natural gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 1. Experimental design and observed tracer movement

    USGS Publications Warehouse

    LeBlanc, Denis R.; Garabedian, Stephen P.; Hess, Kathryn M.; Gelhar, Lynn W.; Quadri, Richard D.; Stollenwerk, Kenneth G.; Wood, Warren W.

    1991-01-01

    A large-scale natural gradient tracer experiment was conducted on Cape Cod, Massachusetts, to examine the transport and dispersion of solutes in a sand and gravel aquifer. The nonreactive tracer, bromide, and the reactive tracers, lithium and molybdate, were injected as a pulse in July 1985 and monitored in three dimensions as they moved as far as 280 m down-gradient through an array of multilevel samplers. The bromide cloud moved horizontally at a rate of 0.42 m per day. It also moved downward about 4 m because of density-induced sinking early in the test and accretion of areal recharge from precipitation. After 200 m of transport, the bromide cloud had spread more than 80 m in the direction of flow, but was only 14 m wide and 4–6 m thick. The lithium and molybdate clouds followed the same path as the bromide cloud, but their rates of movement were retarded about 50% relative to bromide movement because of sorption onto the sediments.

  16. Synthesis and characterization of [BMIM]bromide using microwave-assisted organic synthesis method and its application for dissolution of palm empty fruit bunch

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arianie, Lucy, E-mail: lucy205@yahoo.com; Wahyuningrum, Deana, E-mail: deana@chem.itb.ac.id; Nurrachman, Zeily, E-mail: deana@chem.itb.ac.id

    The decrease of cellulose crystallinity index of palm empty fruit bunch is crucial for the next application of cellulose as raw material for various biofuel and its derivatives. The aim of this research is to decrease the cellulose crystallinity index of palm empty fruit bunch using 1-butyl-3-methylimidazoliumbromide or [BMIM] bromide which has been synthesized using Microwave-Assisted Organic Synthesis (MAOS) method. Conventional reaction method has also been carried out to synthesize [BMIM]bromide for comparison as well. The characterization of synthesized product using FTIR, {sup 1}H-NMR, {sup 13}C-NMR and LC-MS showed that these reactions have been carried out successfully. The results showedmore » that MAOS method is up to 90% faster in producing [BMIM]bromide compare to the conventional method. The application of [BMIM]bromide for dissolution of palm empty fruit bunch showed that cellulose and lignin could be extracted using stirring process for 20 hours. The decrease of cellulose crystallinity index and its morphology changes were identified using FTIR and Scanning Electron Microscope.« less

  17. SYBR safeTM efficiently replaces ethidium bromide in Aspergillus fumigatus gene disruption.

    PubMed

    Canela, H M S; Takami, L A; Ferreira, M E S

    2017-02-08

    Invasive aspergillosis is a disease responsible for high mortality rates, caused mainly by Aspergillus fumigatus. The available drugs are limited and this disease continues to occur at an unacceptable frequency. Gene disruption is essential in the search for new drug targets. An efficient protocol for A. fumigatus gene disruption was described but it requires ethidium bromide, a genotoxic agent, for DNA staining. Therefore, the present study tested SYBR safe TM , a non-genotoxic DNA stain, in A. fumigatus gene disruption protocol. The chosen gene was cipC, which has already been disrupted successfully in our laboratory. A deletion cassette was constructed in Saccharomyces cerevisiae and used in A. fumigatus transformation. There was no statistical difference between the tested DNA stains. The success rate of S. cerevisiae transformation was 63.3% for ethidium bromide and 70% for SYBR safe TM . For A. fumigatus gene disruption, the success rate for ethidium bromide was 100 and 97% for SYBR safe TM . In conclusion, SYBR safe TM efficiently replaced ethidium bromide, making this dye a safe and efficient alternative for DNA staining in A. fumigatus gene disruption.

  18. Synthesis and characterization of [BMIM]bromide using microwave-assisted organic synthesis method and its application for dissolution of palm empty fruit bunch

    NASA Astrophysics Data System (ADS)

    Arianie, Lucy; Wahyuningrum, Deana; Nurrachman, Zeily; Natalia, Dessy

    2014-03-01

    The decrease of cellulose crystallinity index of palm empty fruit bunch is crucial for the next application of cellulose as raw material for various biofuel and its derivatives. The aim of this research is to decrease the cellulose crystallinity index of palm empty fruit bunch using 1-butyl-3-methylimidazoliumbromide or [BMIM] bromide which has been synthesized using Microwave-Assisted Organic Synthesis (MAOS) method. Conventional reaction method has also been carried out to synthesize [BMIM]bromide for comparison as well. The characterization of synthesized product using FTIR, 1H-NMR, 13C-NMR and LC-MS showed that these reactions have been carried out successfully. The results showed that MAOS method is up to 90% faster in producing [BMIM]bromide compare to the conventional method. The application of [BMIM]bromide for dissolution of palm empty fruit bunch showed that cellulose and lignin could be extracted using stirring process for 20 hours. The decrease of cellulose crystallinity index and its morphology changes were identified using FTIR and Scanning Electron Microscope.

  19. Singlet oxygen production by chloroperoxidase-hydrogen peroxide-halide systems.

    PubMed

    Kanofsky, J R

    1984-05-10

    Singlet oxygen production in the chloroperoxidase-hydrogen peroxide-halide system was studied using 1268 nm chemiluminescence. With chloride or bromide ions, singlet oxygen is produced by the mechanism (formula; see text) (formula; see text) where X- is chloride or bromide ion. Under conditions where there is high enzyme activity and when Reaction B is fast relative to Reaction A, singlet oxygen is produced in near stoichiometric amounts. In contrast, when Reaction A is fast relative to Reaction B, oxidized halogen species (chlorine and hypochlorous acid for chloride ion; bromide, tribromide ion, and hypobromous acid for bromide ion) are the principle reaction products. With iodide ion, no 1268 nm chemiluminescence was detected. Past studies have shown that iodine and iodate ion are the major end products of this system.

  20. Investigating the chlorination of acidic pharmaceuticals and by-product formation aided by an experimental design methodology.

    PubMed

    Quintana, José Benito; Rodil, Rosario; López-Mahía, Purificación; Muniategui-Lorenzo, Soledad; Prada-Rodríguez, Darío

    2010-01-01

    The degradation of seven acidic drugs and two metabolites during chlorination was investigated by liquid chromatography-mass spectrometry (LC-MS). A triple-quadrupole (QqQ) system was used to follow the time course of the pharmaceuticals and by-products, while a quadrupole time-of-flight (Q-TOF) system was also used for the identification of the by-products. Under strong chlorination conditions (10mg/L Cl(2), 24h), only four of the target compounds were significantly degraded: salicylic acid, naproxen, diclofenac and indomethacine. The degradation kinetics of these four compounds were investigated at different concentrations of chlorine, bromide and pH by means of a Box-Behnken experimental design. Depending on these factors, measured pseudo-first order half-lives were in the ranges: 23-573h for salicylic acid, 13-446min for naproxen, 5-328min for diclofenac and 0.4-13.4min for indomethacine. Also, it was observed that chlorine concentration was the overall most significant factor, followed by the bromide concentration (except for indomethacine), resulting in increased degradation kinetics as they are increased. The degradation path of salicylic acid, naproxen and diclofenac consisted of aromatic substitution of one or two hydrogens by chlorine and/or bromide. Moreover, for diclofenac, two other by-products corresponding to a decarboxylation/hydroxylation pathway from the monohalogenated products were also identified. On the other hand, indomethacine degradation did not lead to halogenation products but to oxidation ones. The investigation of these by-products in real samples by LC-MS/MS (QqQ) showed that the halogenated derivates of salicylic acid occurred in all the drinking water and wastewater samples analysed.

  1. Control of aliphatic halogenated DBP precursors with multiple drinking water treatment processes: Formation potential and integrated toxicity.

    PubMed

    Zhang, Yimeng; Chu, Wenhai; Yao, Dechang; Yin, Daqiang

    2017-08-01

    The comprehensive control efficiency for the formation potentials (FPs) of a range of regulated and unregulated halogenated disinfection by-products (DBPs) (including carbonaceous DBPs (C-DBPs), nitrogenous DBPs (N-DBPs), and iodinated DBPs (I-DBPs)) with the multiple drinking water treatment processes, including pre-ozonation, conventional treatment (coagulation-sedimentation, pre-sand filtration), ozone-biological activated carbon (O 3 -BAC) advanced treatment, and post-sand filtration, was investigated. The potential toxic risks of DBPs by combing their FPs and toxicity values were also evaluated. The results showed that the multiple drinking water treatment processes had superior performance in removing organic/inorganic precursors and reducing the formation of a range of halogenated DBPs. Therein, ozonation significantly removed bromide and iodide, and thus reduced the formation of brominated and iodinated DBPs. The removal of organic carbon and nitrogen precursors by the conventional treatment processes was substantially improved by O 3 -BAC advanced treatment, and thus prevented the formation of chlorinated C-DBPs and N-DBPs. However, BAC filtration leads to the increased formation of brominated C-DBPs and N-DBPs due to the increase of bromide/DOC and bromide/DON. After the whole multiple treatment processes, the rank order for integrated toxic risk values caused by these halogenated DBPs was haloacetonitriles (HANs)≫haloacetamides (HAMs)>haloacetic acids (HAAs)>trihalomethanes (THMs)>halonitromethanes (HNMs)≫I-DBPs (I-HAMs and I-THMs). I-DBPs failed to cause high integrated toxic risk because of their very low FPs. The significant higher integrated toxic risk value caused by HANs than other halogenated DBPs cannot be ignored. Copyright © 2017. Published by Elsevier B.V.

  2. Data on snow chemistry of the Cascade-Sierra Nevada Mountains

    USGS Publications Warehouse

    Laird, L.B.; Taylor, Howard E.; Lombard, R.E.

    1986-01-01

    Snow chemistry data were measured for solutes found in snow core samples collected from the Cascade-Sierra Nevada Mountains from late February to mid-March 1983. The data are part of a study to assess geographic variations in atmospheric deposition in Washington, Oregon, and California. The constituents and properties include pH and concentrations of hydrogen ion, calcium, magnesium, sodium, potassium, chloride, sulfate, nitrate, fluoride, phosphate, ammonium, iron, aluminum, manganese, copper, cadmium, lead, and dissolved organic carbon. Concentrations of arsenic and bromide were below the detection limit. (USGS)

  3. Neuroinflammatory Pathobiology in Gulf War Illness: Characterization with an Animal Model

    DTIC Science & Technology

    2013-08-01

    GFAP,IL6,CCL2, TNF, L118, Lif, IL10 Hip, Ctx Ctx Ctx CORT=corticosterone;(200mg/L) for days 7-14 P8= pyridostigmine bromide ;P8(2.5 mg/kg/day, s.c...reversible acetylcholinesterase (AChE) inhibitor pyridostigmine bromide (PB), the insect repellent DEET and, potentially, the nerve agent, sarin. These...acetylcholinesterase (AChE) inhibitor, pyridostigmine bromide (PB), the insect repellent, DEET, and, potentially, acutely to the nerve agent sarin. Previously, we

  4. Influence of bromide on the performance of the amphipod Hyalella azteca in reconstituted waters

    USGS Publications Warehouse

    Ivey, Chris D.; Ingersoll, Christopher G.

    2016-01-01

    Poor performance of the amphipod Hyalella azteca has been observed in exposures using reconstituted waters. Previous studies have reported success in H. azteca water-only exposures with the addition of relatively high concentrations of bromide. The present study evaluated the influence of lower environmentally representative concentrations of bromide on the response ofH. azteca in 42-d water-only exposures. Improved performance of H. azteca was observed in reconstituted waters with >0.02 mg Br/L.

  5. Effects of ipratropium bromide and fenoterol aerosols in pulmonary emphysema.

    PubMed Central

    Hughes, J A; Tobin, M J; Bellamy, D; Hutchison, D C

    1982-01-01

    In patients with radiological evidence of pulmonary emphysema the bronchodilator drugs fenoterol and ipratropium bromide produced a considerable increase in vital capacity and reduction in residual volume. The response to fenoterol was virtually complete 15 minutes after administration, but after ipratropium bromide vital capacity was still increasing at 60 minutes. The change in vital capacity was slightly greater with a combination of the two drugs than with either used alone. Changes in FEV1 and peak flow rate were small. Images PMID:6218647

  6. Bromidotetra-kis-(2-ethyl-1H-imidazole-κN (3))copper(II) bromide.

    PubMed

    Godlewska, Sylwia; Kelm, Harald; Krüger, Hans-Jörg; Dołęga, Anna

    2012-12-01

    The Cu(II) ion in the title mol-ecular salt, [CuBr(C5H8N2)4]Br, is coordinated in a square-pyramidal geometry by four N atoms of imidazole ligands and one bromide anion in the apical position. In the crystal, the ions are linked by N-H⋯Br hydrogen bonds involving both the coordinating and the free bromide species as acceptors. A C-H⋯Br inter-action is also observed. Overall, a three-dimensional network results.

  7. A Fundamental Electrochemical Investigation of Bromoaluminate and Mixed Chloro-Bromoaluminate Room Temperature Molten Salt Systems

    DTIC Science & Technology

    1989-03-01

    Non-Aqueous Bromide Research In the late 1950s, Alexander I. Popov and David H. Geske , published a series of papers dealing with the electrochemistry... Geske has also helped to illuminate the electrochemistry occurring in the Zinc-Bromine battery systems. In 1987 Adanuvor et al. studied the effects of the...oxidation waves present in the basic bromide melt system are due to some form of the bromide anion. While Popov and Geske 7 have attributed the first of

  8. Evaluation of Methods for the Analysis of Small Molecular Weight End-Products of Wastewater Ozonation.

    DTIC Science & Technology

    1980-04-01

    advantage over the benzyl bromide method, which easily detected acetic and formic acid levels as low as 0.25 mg/L. Recovery was quantitative, with a...inner diameter glass, packed with 10% OV-l on 80/100 mesh Chromosorb WHP ( Alltech Associates) Carrier: Nitrogen at 24 cc/minute Column temperature: 150°C...found to be effective for analysis of acetic and formic acids. There was no advantage to the use of pentafluorobenzyl bromide over benzyl bromide, even

  9. Lambert-Eaton Myasthenic Syndrome

    MedlinePlus

    ... giving drugs such as di-amino pyridine or pyridostigmine bromide (Mestinon). For patients with small cell lung cancer, ... giving drugs such as di-amino pyridine or pyridostigmine bromide (Mestinon). For patients with small cell lung cancer, ...

  10. Effect of Methyl Bromide on Mycorrhizae and Growth of Sweetgum Seedlings

    Treesearch

    T. H. Filer; E. R. Toole

    1968-01-01

    Fumigation of nursery beds with methyl bromide improved sweetgum, growth by reducing the population of soil-inhabiting pathogens . Although mycorrhizal fungi were reduced, sufficient inoculum survived for rapid mycorrhizal development

  11. Chloride/bromide ratios in leachate derived from farm-animal waste.

    PubMed

    Hudak, Paul F

    2003-01-01

    Ratios of conservative chemicals have been used to identify sources of groundwater contamination. While chloride/bromide ratios have been reported for several common sources of groundwater contamination, little work has been done on leachate derived from farm-animal waste. In this study, chloride/bromide ratios were measured in leachate derived from longhorn-cattle, quarterhorse, and pygme-goat waste at a farm in Abilene, Texas, USA. (Minimum, median, and maximum) chloride/bromide ratios of (66.5, 85.6, and 167), (119, 146, and 156), and (35.4, 57.8, and 165) were observed for cattle, horses, and goats, respectively. These ratios are below typical values for domestic wastewater and within the range commonly observed for oilfield brine. Results of this study have important implications for identifying sources of contaminated groundwater in settings with significant livestock and/or oil production.

  12. Carbene-catalysed reductive coupling of nitrobenzyl bromides and activated ketones or imines via single-electron-transfer process

    NASA Astrophysics Data System (ADS)

    Li, Bao-Sheng; Wang, Yuhuang; Proctor, Rupert S. J.; Zhang, Yuexia; Webster, Richard D.; Yang, Song; Song, Baoan; Chi, Yonggui Robin

    2016-09-01

    Benzyl bromides and related molecules are among the most common substrates in organic synthesis. They are typically used as electrophiles in nucleophilic substitution reactions. These molecules can also be activated via single-electron-transfer (SET) process for radical reactions. Representative recent progress includes α-carbon benzylation of ketones and aldehydes via photoredox catalysis. Here we disclose the generation of (nitro)benzyl radicals via N-heterocyclic carbene (NHC) catalysis under reductive conditions. The radical intermediates generated via NHC catalysis undergo formal 1,2-addition with ketones to eventually afford tertiary alcohol products. The overall process constitutes a formal polarity-inversion of benzyl bromide, allowing a direct coupling of two initially electrophilic carbons. Our study provides a new carbene-catalysed reaction mode that should enable unconventional transformation of (nitro)benzyl bromides under mild organocatalytic conditions.

  13. Dosage effect of rocuronium on intraoperative neuromonitoring in patients undergoing thyroid surgery.

    PubMed

    Han, Yang-dong; Liang, Feng; Chen, Peng

    2015-01-01

    The effect of different concentrations of rocuronium bromide used for anesthesia induction during thyroid surgery on the intraoperative recurrent laryngeal nerve monitoring was evaluated. One hundred patients undergoing thyroid operation were randomized into five groups (20 patients per group). Patients in group I were operated and monitored without the use of rocuronium bromide. Patients in groups II-V were respectively injected with 0.5x, 1x, 1.5x, and 2x ED95 rocuronium bromide intravenously. The time from injecting the rocuronium bromide to the beginning of tube insertion was recorded, the conditions of tracheal intubation were evaluated, and the changes in blood pressure and pulse during the intubation process were monitored. Vagus nerve/recurrent laryngeal nerve evoked muscle potential was monitored using the NIM-Response3.0 nerve electromyography monitor. The amplitude of electromyography signal was recorded every 5 min during 30 min after successful tracheal intubation. The tracheal intubation success rate was 100% in all groups. Compared with group I, intubating condition scores (Cooper scores) in the patients of groups II-V were higher (P < 0.05). The stability of intraoperative neuromonitoring signal amplitude in groups I-III met the monitoring standards. The findings suggest that the use of 0.5x or 1x ED95 rocuronium bromide during the anesthesia induction can improve the tracheal tube conditions without affecting the intraoperative recurrent laryngeal nerve monitoring. The use of 1x ED95 rocuronium bromide induction was associated with the best results.

  14. Hydrogen bonding Part 53. Correlation of differential scanning calorimetric data with IR and dissociation vapor pressure studies of transitions of hexamethonium chloride and bromide dihydrates and hexamethonium bromide monohydrate

    NASA Astrophysics Data System (ADS)

    Snider, Barbara L.; Harmon, Kenneth M.

    1994-03-01

    Differential scanning calorimetry of hexamethonium chloride dihydrate shows an endothermic transition of 2.70 kcal mol -1 at 36.81°C. This correlates well with the temperatures observed by IR spectra (36°C) and equilibrium dissociation vapor pressure studies (37°C) for the transition between Type I planar cluster and Type II extended linear HOH⋯Cl - hydrogen bonding, and with the value of 2.77 kcal mol -1 for this transition derived by Hess' law treatment of dissociation vapor pressure data. Differential scanning calorimetry of hexamethonium bromide shows a rapid endothermic transition of 2.38 kcal mol -1 at 35.15°C and a very slow endothermic transition of about 12-13 kcal mol -1 centered near 50°C. This latter endotherm corresponds to the transition between Type I and Type II HOH⋯Br - hydrogen bonding observed by IR and vapor pressure studies at 49°C. The nature of the 35.15°C endotherm is not known. Hexamethonium bromide also shows a third endotherm at 142.91°C, which presumably results from melting of hydrate in the sealed DSC cell. Combined analysis of differential scanning calorimetry and dissociation vapor pressure data predicts a value of about -13 kcal mol -1 for an exothermic disproportionation at 52°C of two hexamethonium bromide monohydrate to Type II dihydrate and anhydrous bromide.

  15. X-ray Absorption Spectroscopic Characterization of the Synthesis Process: Revealing the Interactions in Cetyltrimethylammonium Bromide-Modified Sulfur–Graphene Oxide Nanocomposites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ye, Yifan; Kawase, Ayako; Song, Min-Kyu

    In this paper, we have investigated the chemical bonding interaction of S in a CTAB (cetyltrimethylammonium bromide, CH 3(CH 2) 15N +(CH 3) 3Br –)-modified sulfur–graphene oxide (S–GO) nanocomposite used as the cathode material for Li/S cells by S K-edge X-ray absorption spectroscopy (XAS). The results show that the introduction of CTAB to the S–GO nanocomposite and changes in the synthesis recipe including alteration of the S precursor ratios and the sequence of mixing ingredients lead to the formation of different S species. CTAB modifies the cathode materials through bonding with Na 2S x in the precursor solution, which ismore » subsequently converted to C–S bonds during the heat treatment at 155 °C. Moreover, GO bonds with CTAB and acts as the nucleation center for S precipitation. Finally, all these interactions among S, CTAB, and GO help to immobilize the sulfur in the cathode and may be responsible for the enhanced cell cycle life of CTAB–S–GO nanocomposite-based Li/S cells.« less

  16. Primula auriculata Extracts Exert Cytotoxic and Apoptotic Effects against HT-29 Human Colon Adenocarcinoma Cells.

    PubMed

    Behzad, Sahar; Ebrahim, Karim; Mosaddegh, Mahmoud; Haeri, Ali

    2016-01-01

    Primula auriculata (Tootia) is one of the most important local medicinal plants in Hamedan district, Iran. To investigate cytotoxicity and apoptosis induction of crude methanolic extract and different fraction of it, we compared several methods on HT-29 human colon Adenocarcinoma cells. Cancer cell proliferation was measured by 3-(4, 5‑dimethylthiazolyl)2, 5‑diphenyl‑tetrazolium bromide (MTT) assay and apoptosis induction was analyzed by fluorescence microscopy (acridin orange/ethidium bromide, annexin V/propidium iodide staining, TUNEL assay and Caspase-3 activity assay). Crude methanolic extract (CM) inhibited the growth of malignant cells in a dose-dependent manner. Among solvent fractions, the dichloromethane fraction (CF) was found to be the most toxic compared to other fractions. With double staining methods, high percentage of 40 µg/mL of (CM) and (CF) treated cells exhibited typical characteristics of apoptotic cells. Apoptosis induction was also revealed by apoptotic fragmentation of nuclear DNA and activation of caspas-3 in treated cells. These findings indicate that crude methanolic extract and dichloromethan fraction of P.auriculata induced apoptosis and inhibited proliferation in colon cancer cells and could be used as a source for new lead structures in drug design to combat colon cancer.

  17. X-ray Absorption Spectroscopic Characterization of the Synthesis Process: Revealing the Interactions in Cetyltrimethylammonium Bromide-Modified Sulfur–Graphene Oxide Nanocomposites

    DOE PAGES

    Ye, Yifan; Kawase, Ayako; Song, Min-Kyu; ...

    2016-04-22

    In this paper, we have investigated the chemical bonding interaction of S in a CTAB (cetyltrimethylammonium bromide, CH 3(CH 2) 15N +(CH 3) 3Br –)-modified sulfur–graphene oxide (S–GO) nanocomposite used as the cathode material for Li/S cells by S K-edge X-ray absorption spectroscopy (XAS). The results show that the introduction of CTAB to the S–GO nanocomposite and changes in the synthesis recipe including alteration of the S precursor ratios and the sequence of mixing ingredients lead to the formation of different S species. CTAB modifies the cathode materials through bonding with Na 2S x in the precursor solution, which ismore » subsequently converted to C–S bonds during the heat treatment at 155 °C. Moreover, GO bonds with CTAB and acts as the nucleation center for S precipitation. Finally, all these interactions among S, CTAB, and GO help to immobilize the sulfur in the cathode and may be responsible for the enhanced cell cycle life of CTAB–S–GO nanocomposite-based Li/S cells.« less

  18. Crystal structure of hexa­kis­(urea-κO)chromium(III) dichromate bromide monohydrate from synchrotron X-ray data

    PubMed Central

    Moon, Dohyun; Tanaka, Shinnosuke; Akitsu, Takashiro; Choi, Jong-Ha

    2015-01-01

    The title bromide salt, [Cr{CO(NH2)2}6](Cr2O7)Br·H2O, is isotypic to the corresponding chloride salt. Within the complex cation, the CrIII atom is coordinated by six O atoms of six urea ligands, displaying a slightly distorted octa­hedral coordination environment. The Cr—O bond lengths involving the urea ligands are in the range 1.9534 (13)–1.9776 (12) Å. The Cr2O7 2− anion has a nearly staggered conformation, with a bridging angle of 130.26 (10)°. The individual components are arranged in rows extending parallel to [100]. The Br− anion links the complex cation, as well as the solvent water mol­ecule, through N—H⋯Br and O—H⋯Br hydrogen-bonding inter­actions. The supra­molecular architecture also includes N—H⋯O and O—H⋯O hydrogen bonding between urea N—H and water O—H donor groups and the O atoms of the Cr2O7 2− anion as acceptor atoms, leading to a three-dimensional network structure. PMID:26594505

  19. Novel insight into antimicrobial resistance and sensitivity phenotypes associated to qac and norA genotypes in Staphylococcus aureus.

    PubMed

    Marchi, Emmanuela; Furi, Leonardo; Arioli, Stefania; Morrissey, Ian; Di Lorenzo, Valeria; Mora, Diego; Giovannetti, Luciana; Oggioni, Marco Rinaldo; Viti, Carlo

    2015-01-01

    Staphylococcus aureus strains harboring QacA, QacB, QacC, QacG transporters and norA promoter up-regulating mutations were characterized by phenotype microarray (PM), standard methods for susceptibility testing, and ethidium bromide efflux assays, in order to increase knowledge on phenotypes associated to efflux pumps and their substrates. PM data and standard susceptibility testing lead to the identification of new potential efflux targets, such as guanidine hydrochloride or 8-hydroxyquinoline for QacA and QacC pumps, respectively. The identification of compounds to which the presence of efflux pumps induced increased susceptibility opens new perspectives for potential adjunct anti-resistance treatment (i.e. strains bearing QacB transporters showed increased susceptibility to thioridazine, amitriptyline and orphenadrine). Although the tested isolates were characterized by high degree of heterogeneity, a hallmark of clinical isolates, direct ethidium bromide efflux assays were effective in highlighting differences in efflux efficiency among strains. These data add to characterization of substrate specificity in the different classes of staphylococcal multidrug efflux systems conferring specific substrate profiles and efflux features to each of them. Copyright © 2014 Elsevier GmbH. All rights reserved.

  20. A master dynamic flow diagram for the shear thickening transition in micellar solutions.

    PubMed

    Bautista, F; Tepale, N; Fernández, V V A; Landázuri, G; Hernández, E; Macías, E R; Soltero, J F A; Escalante, J I; Manero, O; Puig, J E

    2016-01-07

    The shear thickening behavior of dilute micellar solutions of hexadecyltrimethylammonium-type surfactants with different counterions (tosylate, 3- and 4-fluorobenzoate, vinylbenzoate and salicylate) and of n-alkyltetradecylammonium bromide (CnTAB), with n = 14, 16 and 18, is examined here. These solutions undergo a shear thickening transition due to the formation of shear-induced structures (SISs) in the shear range studied. Here we report a relationship between the shear thickening intensity and the differences in the hydrophobicity of counterions according to the Hofmeister-like anion series, which leads to a master flow diagram. This master flow diagram is produced by plotting a normalized shear thickening intensity (Iη - 1)/(Imax - 1) versus CD/CD,max, where Iη is the shear-thickening intensity, defined as the largest viscosity obtained in the shear-thickening transition (STT) at a given surfactant concentration CD divided by the Newtonian viscosity η0, and Imax is the largest intensity value obtained in the STT at a surfactant concentration CD,max. The master flow diagram is built using several cetyltrimethylammonium-type surfactants with different counterions, according to a Hofmeister-like series, and by n-alkyltetradecylammonium bromide surfactants with different alkyl chain lengths.

  1. NLP-1: a DNA intercalating hypoxic cell radiosensitizer and cytotoxin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Panicucci, R.; Heal, R.; Laderoute, K.

    The 2-nitroimidazole linked phenanthridine, NLP-1 (5-(3-(2-nitro-1-imidazoyl)-propyl)-phenanthridinium bromide), was synthesized with the rationale of targeting the nitroimidazole to DNA via the phenanthridine ring. The drug is soluble in aqueous solution (greater than 25 mM) and stable at room temperature. It binds to DNA with a binding constant 1/30 that of ethidium bromide. At a concentration of 0.5 mM, NLP-1 is 8 times more toxic to hypoxic than aerobic cells at 37 degrees C. This concentration is 40 times less than the concentration of misonidazole, a non-intercalating 2-nitroimidazole, required for the same degree of hypoxic cell toxicity. The toxicity of NLP-1 ismore » reduced at least 10-fold at 0 degrees C. Its ability to radiosensitize hypoxic cells is similar to misonidazole at 0 degrees C. Thus the putative targeting of the 2-nitroimidazole, NLP-1, to DNA, via its phenanthridine group, enhances its hypoxic toxicity, but not its radiosensitizing ability under the present test conditions. NLP-1 represents a lead compound for intercalating 2-nitroimidazoles with selective toxicity for hypoxic cells.« less

  2. Bromate formation from the oxidation of bromide in the UV/chlorine process with low pressure and medium pressure UV lamps.

    PubMed

    Fang, Jingyun; Zhao, Quan; Fan, Chihhao; Shang, Chii; Fu, Yun; Zhang, Xiangru

    2017-09-01

    When a bromide-containing water is treated by the ultraviolet (UV)/chlorine process, hydroxyl radicals (HO) and halogen radicals such as Cl or Br are formed due to the UV photolysis of free halogens. These reactive species may induce the formation of bromate, which is a probable human carcinogen. Bromate formation in the UV/chlorine process using low pressure (LP) and medium pressure (MP) lamps in the presence of bromide was investigated in the present study. The UV/chlorine process significantly enhanced bromate formation as compared to dark chlorination. The bromate formation was elevated with increasing UV fluence, bromide concentration, and pH values under both LP and MP UV irradiations. It was significantly enhanced at pH 9 compared to those at pH 6 and 7 with MP UV irradiation, while it was slightly enhanced at pH 9 with LP UV. The formation by UV/chlorine process started with the formation of free bromine (HOBr/OBr - ) through the reaction of chlorine and bromide, followed by a subsequent oxidation of free bromine and formation of BrO and bromate by reacting with radicals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Direct measurement of torque and twist generated by a dye binding to DNA

    NASA Astrophysics Data System (ADS)

    Gore, Jeff; Bryant, Zev; Bustamante, Carlos

    2004-03-01

    Many biologically important chemicals and proteins change the twist of DNA upon binding. We have used magnetic tweezers to directly measure the torque and twist generated when ethidium bromide binds and unbinds to DNA. One end of the DNA is bound specifically to a glass coverslip and the opposite end is held away from the surface by a paramagnetic bead. Attached to the middle of the DNA is a second fluorescent bead whose position can be tracked with high angular and temporal resolution. On one side of the fluorescent bead binding site we have engineered a single strand nick that acts like a free swivel. Addition of ethidium bromide then powered rotation of the central fluorescent bead. After the ethidium bromide was bound we used magnesium to compete out the intercalated ethidium bromide, thus inducing a rotation in the opposite direction. We studied the torque generation, energetics, and kinetics associated with ethidium bromide binding and unbinding by tracking the rotation of the fluorescent bead. This system is a demonstration of a reversible chemically powered DNA-based rotary motor. We also expect that this technique will be useful in studying proteins that bind to or rotate DNA, including recA, polymerases, and topoisomerases.

  4. Effect of increasing bromide concentration on toxicity in treated drinking water.

    PubMed

    Sawade, Emma; Fabris, Rolando; Humpage, Andrew; Drikas, Mary

    2016-04-01

    Research is increasingly indicating the potential chronic health effects of brominated disinfection by-products (DBPs). This is likely to increase with elevated bromide concentrations resulting from the impacts of climate change, projected to include extended periods of drought and the sudden onset of water quality changes. This will demand more rigorous monitoring throughout distribution systems and improved water quality management at water treatment plants (WTPs). In this work the impact of increased bromide concentration on formation of DBPs following conventional treatment and chlorination was assessed for two water sources. Bioanalytical tests were utilised to determine cytotoxicity of the water post disinfection. Coagulation was shown to significantly reduce the cytotoxicity of the water, indicating that removal of natural organic matter DBP precursors continues to be an important factor in drinking water treatment. Most toxic species appear to form within the first half hour following disinfectant addition. Increasing bromide concentration across the two waters was shown to increase the formation of trihalomethanes and shifted the haloacetic acid species distribution from chlorinated to those with greater bromine substitution. This correlated with increasing cytotoxicity. This work demonstrates the challenges faced by WTPs and the possible effects increasing levels of bromide in source waters could have on public health.

  5. [Bioequivalence of pyridostigmine bromide dispersible tablets in rabbits].

    PubMed

    Wang, Hong; Wang, Hong; Tan, Qun-you; Zhang, Li; Cheng, Xun-guan; Zhang, Jing-qing

    2011-10-01

    To compare the pharmacokinetic parameters of pyridostigmine bromide dispersible tablets and common tablets in rabbits. Twelve rabbits were given an oral dose (60 mg) of pyridostigmine bromide dispersible tablets or common tablets in a randomized crossover study. The plasma concentration of pyridostigmine bromide was determined by reversed-phase ion pair chromatography. The pharmacokinetic parameters were calculated using DAS2.1.1 software. The pharmacokinetic parameters showed no significant differences in rabbit plasma between pyridostigmine bromide dispersible tablets and common tablets. The two tablets had a C(max) of 1.83∓0.08 mg·L(-1) and 1.68∓0.03 mg·L(-1), tmax of 2.33∓0.41 h and 2.58∓0.20 h, AUC(0-24) of 15.50∓0.62 mg·h·L(-1) and 15.14∓0.30 mg·h·L(-1), AUC(0-∞) of 15.82∓0.70 mg·h·L(-1) and 15.57∓0.32 mg·h·L(-1), respectively. The relative bioavailability F(0-24) was 102.38% and F(0-∞) was 101.61% for the dispersible tablets. The two tablets are bioequivalent in rabbits.

  6. 7 CFR 305.6 - Methyl bromide fumigation treatment schedules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., fumigation with methyl bromide for sapote fruit fly. Regulated citrus fruits originating inside an area quarantined for sapote fruit fly that are to be moved outside the quarantined area may be treated with methyl...

  7. 7 CFR 319.40-6 - Universal importation options.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... areas; or (B) Fumigated with methyl bromide in accordance with part 305 of this chapter, heat treated in..., unless accompanied by an importer document stating that the entire lot was fumigated with methyl bromide...

  8. White-Light Emission and Structural Distortion in New Corrugated Two-Dimensional Lead Bromide Perovskites.

    PubMed

    Mao, Lingling; Wu, Yilei; Stoumpos, Constantinos C; Wasielewski, Michael R; Kanatzidis, Mercouri G

    2017-03-29

    Hybrid inorganic-organic perovskites are developing rapidly as high performance semiconductors. Recently, two-dimensional (2D) perovskites were found to have white-light, broadband emission in the visible range that was attributed mainly to the role of self-trapped excitons (STEs). Here, we describe three new 2D lead bromide perovskites incorporating a series of bifunctional ammonium dications as templates which also emit white light: (1) α-(DMEN)PbBr 4 (DMEN = 2-(dimethylamino)ethylamine), which adopts a unique corrugated layered structure in space group Pbca with unit cell a = 18.901(4) Å, b = 11.782(2) Å, and c = 23.680(5) Å; (2) (DMAPA)PbBr 4 (DMAPA = 3-(dimethylamino)-1-propylamine), which crystallizes in P2 1 /c with a = 10.717(2) Å, b = 11.735(2) Å, c = 12.127(2) Å, and β = 111.53(3)°; and (3) (DMABA)PbBr 4 (DMABA = 4-dimethylaminobutylamine), which adopts Aba2 with a = 41.685(8) Å, b = 23.962(5) Å, and c = 12.000(2) Å. Photoluminescence (PL) studies show a correlation between the distortion of the "PbBr 6 " octahedron in the 2D layer and the broadening of PL emission, with the most distorted structure having the broadest emission (183 nm full width at half-maximum) and longest lifetime (τ avg = 1.39 ns). The most distorted member α-(DMEN)PbBr 4 exhibits white-light emission with a color rendering index (CRI) of 73 which is similar to a fluorescent light source and correlated color temperature (CCT) of 7863 K, producing "cold" white light.

  9. Mixtures of Quaternary Ammonium Compounds and Long-chain Fatty Acids as Antifungal Agents

    PubMed Central

    Kull, F. C.; Eisman, P. C.; Sylwestrowicz, H. D.; Mayer, R. L.

    1961-01-01

    The influence of undecylenic acid on the fungistatic effect of phenoxyethyldimethyldodecylammonium bromide (Domiphen bromide) against Trichophyton mentagrophytes was investigated. The unsaturated fatty acid was found to enhance the fungistatic activity of Domiphen bromide against this organism. The ratio of concentrations of these agents has a marked influence on the results of in vitro tests for antifungal action resulting in a completely different effect than heretofore noted in combination experiments against bacteria. The enhancing phenomenon is not particular to T. mentagrophytes, it was observed also with Candida albicans. PMID:14460466

  10. Bromidotetra­kis­(2-ethyl-1H-imidazole-κN 3)copper(II) bromide

    PubMed Central

    Godlewska, Sylwia; Kelm, Harald; Krüger, Hans-Jörg; Dołęga, Anna

    2012-01-01

    The CuII ion in the title mol­ecular salt, [CuBr(C5H8N2)4]Br, is coordinated in a square-pyramidal geometry by four N atoms of imidazole ligands and one bromide anion in the apical position. In the crystal, the ions are linked by N—H⋯Br hydrogen bonds involving both the coordinating and the free bromide species as acceptors. A C—H⋯Br inter­action is also observed. Overall, a three-dimensional network results. PMID:23468738

  11. Buscopan labeled with carbon-14 and deuterium.

    PubMed

    Latli, Bachir; Stiasni, Michael; Hrapchak, Matt; Li, Zhibin; Grinberg, Nelu; Lee, Heewon; Busacca, Carl A; Senanayake, Chris H

    2016-11-01

    Hyosine butyl bromide, the active ingredient in Buscopan, is an anticholinergic and antimuscarinic drug used to treat pain and discomfort caused by abdominal cramps. A straightforward synthesis of carbon-14- and deuterium-labeled Buscopan was developed using scopolamine, n-butyl-1- 14 C bromide, and n-butyl- 2 H 9 bromide, respectively. In a second carbon-14 synthesis, the radioactive carbon was incorporated in the tropic acid moiety to follow its metabolism. Herein, we describe the detailed preparations of carbon-14- and deuterium-labeled Buscopan. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Removal of lead and phosphate ions from aqueous solutions by organo-smectite.

    PubMed

    Bajda, Tomasz; Szala, Barbara; Solecka, Urszula

    2015-01-01

    Smectite has been modified using hexadecyltrimethyl ammonium bromide in an amount of double cationic exchange capacity. This alteration makes it possible to use organo-smectite as a sorbent to remove anionic forms. The experiment consisted of the interchangeable sorption of phosphate(V) and lead(II) by organo-smectite. Research was carried out with varying pH (2-5) and various concentrations (0.1-5 mmol/L). Organo-smectite with previously adsorbed lead ions removed more phosphate than the untreated organo-smectite. Experimental data show that lead is more likely to absorb on the organo-smectite than on the organo-smectite with previously adsorbed phosphate ions. It follows that the most effective use of the organo-smectite is through the sorption of first - Pb cations and then PO4 anions. With an increasing concentration of Pb(II) or P(V), the sorption efficiency increases. The maximum sorption efficiency of lead and phosphate ions is observed at pH 5. This enables the removal of harmful lead and phosphorus compounds from waste water and immobilizes them on the sorbent's surface. The alternating reactions of lead and phosphorus ions result in the crystallization of brompyromorphite Pb5(PO4)3Br.

  13. The study of colloidal lead bromide perovskite nanocrystals and its application in hybrid solar cells

    NASA Astrophysics Data System (ADS)

    Usman, Khurram; Ming, Shuaiqiang; Liu, Xiaohui; Li, Xiaodong; Gui, Zhenzhen; Xie, Qiaomu; Zhang, Wenxiao; Wu, Yulei; Wang, Hai-Qiao; Fang, Junfeng

    2018-03-01

    In this study, we investigated inorganic cesium lead halide perovskite semiconductor and tested its application in photovoltaics. Highly crystalline material was synthesized by two different approaches, including a high temperature route and a low temperature method. Inorganic-polymer hybrid solar cells based on solution-deposited layers of CsPbBr3 nanocrystals were successfully fabricated in ambient, with and without post treatments. The solar cells employing nanocrystals with short ligands, obtained from low temperature route, outperformed the devices with long ligands. The devices exhibited an efficiency up to 1.16%, with an open circuit voltage (V oc) of 0.87 V, a fill factor of 56.2% and a short-circuit current density (J sc) of 2.38 mA/cm2.

  14. Test report :

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rose, David Martin; Schenkman, Benjamin L.; Borneo, Daniel R.

    2013-08-01

    The Department of Energy Office of Electricity (DOE/OE), Sandia National Laboratory (SNL) and the Base Camp Integration Lab (BCIL) partnered together to incorporate an energy storage system into a microgrid configured Forward Operating Base to reduce the fossil fuel consumption and to ultimately save lives. Energy storage vendors have supplied their systems to SNL Energy Storage Test Pad (ESTP) for functional testing and a subset of these systems were selected for performance evaluation at the BCIL. The technologies tested were electro-chemical energy storage systems comprised of lead acid, lithium-ion or zinc-bromide. MILSPRAY Military Technologies has developed an energy storage systemmore » that utilizes lead acid batteries to save fuel on a military microgrid. This report contains the testing results and some limited assessment of the Milspray Scorpion Energy Storage Device.« less

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yoon, Seog Joon; Kuno, Masaru; Kamat, Prashant V.

    Minimizing photoinduced segregation in mixed halide lead perovskites is important for achieving stable photovoltaic performance. The shift in the absorption and the rate of formation of iodide- and bromide-rich regions following visible excitation of mixed halide lead perovskites is found to strongly depend on the halide ion concentration. Slower formation and recovery rates observed in halide-deficient films indicate the involvement of defect sites in influencing halide phase segregation. At higher halide concentrations (in stoichiometric excess), segregation effects become less prominent, as evidenced by faster recovery kinetics. These results suggest that light-induced compositional segregation can be minimized in mixed halide perovskitemore » films by using excess halide ions. In conclusion, the findings from this study further reflect the importance of halide ion post-treatment of perovskite films to improve their solar cell performance.« less

  16. Chlorination of bromide-containing waters: enhanced bromate formation in the presence of synthetic metal oxides and deposits formed in drinking water distribution systems.

    PubMed

    Liu, Chao; von Gunten, Urs; Croué, Jean-Philippe

    2013-09-15

    Bromate formation from the reaction between chlorine and bromide in homogeneous solution is a slow process. The present study investigated metal oxides enhanced bromate formation during chlorination of bromide-containing waters. Selected metal oxides enhanced the decay of hypobromous acid (HOBr), a requisite intermediate during the oxidation of bromide to bromate, via (i) disproportionation to bromate in the presence of nickel oxide (NiO) and cupric oxide (CuO), (ii) oxidation of a metal to a higher valence state in the presence of cuprous oxide (Cu2O) and (iii) oxygen formation by NiO and CuO. Goethite (α-FeOOH) did not enhance either of these pathways. Non-charged species of metal oxides seem to be responsible for the catalytic disproportionation which shows its highest rate in the pH range near the pKa of HOBr. Due to the ability to catalyze HOBr disproportionation, bromate was formed during chlorination of bromide-containing waters in the presence of CuO and NiO, whereas no bromate was detected in the presence of Cu2O and α-FeOOH for analogous conditions. The inhibition ability of coexisting anions on bromate formation at pH 8.6 follows the sequence of phosphate > sulfate > bicarbonate/carbonate. A black deposit in a water pipe harvested from a drinking water distribution system exerted significant residual oxidant decay and bromate formation during chlorination of bromide-containing waters. Energy dispersive spectroscopy (EDS) analyses showed that the black deposit contained copper (14%, atomic percentage) and nickel (1.8%, atomic percentage). Cupric oxide was further confirmed by X-ray diffraction (XRD). These results indicate that bromate formation may be of concern during chlorination of bromide-containing waters in distribution systems containing CuO and/or NiO. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Use of Soybean Lecithin in Shape Controlled Synthesis of Gold Nanoparticles

    NASA Astrophysics Data System (ADS)

    Ayres, Benjamin Robert

    The work presented in this dissertation is a composite of experiments in the growth of gold nanoparticles with specific optical properties of interest. The goal is to synthesize these gold nanoparticles using soybean extract for not only shape control, but for propensity as a biocompatible delivery system. The optical properties of these nanoparticles has found great application in coloring glass during the Roman empire and, over the centuries, has grown into its own research field in applications of nanoparticulate materials. Many of the current functions include use in biological systems as biosensors and therapeutic applications, thus making biocompatibility a necessity. Current use of cetyltrimethylammonium bromide leads to rod-shaped gold nanoparticles, however, the stability of these gold nanoparticles does not endure for extended periods of time in aqueous media. In my research, two important components were found to be necessary for stable, anisotropic growth of gold nanoparticles. In the first experiments, it was found that bromide played a key role in shape control. Bromide exchange on the gold atoms led to specific packing of the growing crystals, allowing for two-dimensional growth of gold nanoparticles. It was also discerned that soybean lecithin contained ligands that blocked specific gold facets leading to prismatic gold nanoparticle growth. These gold nanoprisms give a near infrared plasmon absorption similar to that of rod-shaped gold nanoparticles. These gold nanoprisms are discovered to be extremely stable in aqueous media and remain soluble for extended periods of time, far longer than that of gold nanoparticles grown using cetyltrimethylammonium bromide. Since soy lecithin has a plethora of compounds present, it became necessary to discover which compound was responsible for the shape control of the gold nanoprisms in order to optimize the synthesis and allow for a maximum yield of the gold nanoprisms. Many of these components were identified by high performance liquid chromatography and liquid chromatography-mass spectrometry. However, re-spike of these components into growth solutions did not enhance the growth of gold nanoprisms. Upon separating the shapes of the gold nanoparticles using gel electrophoresis, addition of KCN to the separated gold nanoparticles allowed us to extract the culpable ligands for shape control. Analysis of these ligands by mass spectrometry elucidated the identity of PA and upon re-spike of the PA into a growth solution of PC95, the growth of a near-infrared plasmon absorption was seen. The stability of these gold nanoparticles was tested with and without the addition of decane thiol and it was concluded that addition of the thiol allowed for improved stability of the gold nanoparticles towards cyanide. It was determined that at a concentration of 2 μM decanethiol, spherical gold nanoparticles remained stable to cyanide at the expense of the prismatic gold nanoparticles. However, at 5 μM decanethiol, both spherical and prismatic gold nanoparticles retained stability to cyanide in aqueous conditions.

  18. Cyanogen bromide

    Integrated Risk Information System (IRIS)

    Cyanogen bromide ; CASRN 506 - 68 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  19. Methyl Bromide Commodity Fumigation Buffer Zone Lookup Tables

    EPA Pesticide Factsheets

    Product labels for methyl bromide used in commodity and structural fumigation include requirements for buffer zones around treated areas. The information on this page will allow you to find the appropriate buffer zone for your planned application.

  20. Seeded Growth of Monodisperse Gold Nanorods Using Bromide-Free Surfactant Mixtures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ye, XC; Gao, YZ; Chen, J

    We demonstrate for the first time that monodisperse gold nanorods (NRs) with broadly tunable dimensions and longitudinal surface plasmon resonances can be synthesized using a bromide-free surfactant mixture composed of alkyltrimethylammonium chloride and sodium oleate. It is found that uniform gold NRs can be obtained even with an iodide concentration approaching 100 mu M in the growth solution. In contrast to conventional wisdom, our results provide conclusive evidence that neither bromide as the surfactant counterion nor a high concentration of bromide ions in the growth solution is essential for gold NR formation. Correlated electron microscopy study of three-dimensional structures ofmore » gold NRs reveals a previously unprecedented octagonal prismatic structure enclosed predominantly by high index {310} crystal planes. These findings should have profound implications for a comprehensive mechanistic understanding of seeded growth of anisotropic metal nanocrystals.« less

  1. Carbene-catalysed reductive coupling of nitrobenzyl bromides and activated ketones or imines via single-electron-transfer process

    PubMed Central

    Li, Bao-Sheng; Wang, Yuhuang; Proctor, Rupert S. J.; Zhang, Yuexia; Webster, Richard D.; Yang, Song; Song, Baoan; Chi, Yonggui Robin

    2016-01-01

    Benzyl bromides and related molecules are among the most common substrates in organic synthesis. They are typically used as electrophiles in nucleophilic substitution reactions. These molecules can also be activated via single-electron-transfer (SET) process for radical reactions. Representative recent progress includes α-carbon benzylation of ketones and aldehydes via photoredox catalysis. Here we disclose the generation of (nitro)benzyl radicals via N-heterocyclic carbene (NHC) catalysis under reductive conditions. The radical intermediates generated via NHC catalysis undergo formal 1,2-addition with ketones to eventually afford tertiary alcohol products. The overall process constitutes a formal polarity-inversion of benzyl bromide, allowing a direct coupling of two initially electrophilic carbons. Our study provides a new carbene-catalysed reaction mode that should enable unconventional transformation of (nitro)benzyl bromides under mild organocatalytic conditions. PMID:27671606

  2. Determination of trace quaternary ammonium surfactants in water by combining solid-phase extraction with surface-assisted laser desorption/ionization mass spectrometry.

    PubMed

    Chen, Y C; Sun, M C

    2001-01-01

    This study demonstrates the feasibility of combining solid-phase extraction (SPE) with surface-assisted laser desorption/ionization (SALDI) mass spectrometry to determine trace quaternary ammonium surfactants in water. The trace surfactants in water were directly concentrated on the surface of activated carbon sorbent in SPE. The activated carbon sorbent was then mixed with the SALDI liquid for SALDI analysis. No SPE elution procedure was necessary. Experimental results indicate that the surfactants with longer chain alkyl groups exhibit higher sensitivities than those with shorter chain alkyl groups in SPE-SALDI analysis. The detection limit for hexadecyltrimethylammonium bromide is around 10 ppt in SPE-SALDI analysis by sampling 100 mL of aqueous solution, while that of tetradecyltrimethylammonium bromide is about 100 ppt. The detection limit for decyltrimethylammonium bromide and dodecyltrimethylammonium bromide is in the low-ppb range. Copyright 2001 John Wiley & Sons, Ltd.

  3. Effect of preconditioning on silver leaching and bromide removal properties of silver-impregnated activated carbon (SIAC).

    PubMed

    Rajaeian, Babak; Allard, Sébastien; Joll, Cynthia; Heitz, Anna

    2018-07-01

    Silver impregnated activated carbon (SIAC) has been found to be effective in mitigating the formation of brominated-disinfection by products during drinking water treatment. However, there are still uncertainties regarding its silver leaching properties, and strategies for the prevention of silver leaching have remained elusive. This study focused on the evaluation of one type of commercially available SIAC for its ability to remove bromide while minimising silver leaching from the material. Both synthetic and real water matrices were tested. Depending on solution pH, it was found that changing the surface charge properties of SIAC, as measured by the point of zero charge pH, can result in additional bromide removal while minimising the extent of silver leaching. To better understand the mechanism of silver leaching from the SIAC, eight preconditioning environments, i.e. variable pH and ionic strength were tested for a fixed amount of SIAC and two preconditioning environments were selected for a more detailed investigation. Experiments carried out in synthetic water showed that preconditioning at pH 10.4 did not deteriorate the capacity of SIAC to remove bromide, but significantly decreased the release of silver in the form of ionic silver (Ag + ), silver bromide (AgBr) and silver chloride (AgCl) from 40% for the pristine to 3% for the treated SIAC. This was confirmed using a groundwater sample. These results suggest that preconditioned SIAC has the potential to be an effective method for bromide removal with minimised silver leaching in a long-term field application for drinking water production. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. [The effects of intra-cerebroventricular administered rocuronium on the central nervous system of rats and determination of its epileptic seizure-inducing dose].

    PubMed

    Baykal, Mehmet; Gökmen, Necati; Doğan, Alper; Erbayraktar, Serhat; Yılmaz, Osman; Ocmen, Elvan; Erdost, Hale Aksu; Arkan, Atalay

    The aim of this study was to investigate the effects of intracerebroventricularly administered rocuronium bromide on the central nervous system, determine the seizure threshold dose of rocuronium bromide in rats, and investigate the effects of rocuronium on the central nervous system at 1/5, 1/10, and 1/100 dilutions of the determined seizure threshold dose. A permanent cannula was placed in the lateral cerebral ventricle of the animals. The study was designed in two phases. In the first phase, the seizure threshold dose of rocuronium bromide was determined. In the second phase, Group R 1/5 (n=6), Group 1/10 (n=6), and Group 1/100 (n=6) were formed using doses of 1/5, 1/10, and 1/100, respectively, of the obtained rocuronium bromide seizure threshold dose. The rocuronium bromide seizure threshold value was found to be 0.056±0.009μmoL. The seizure threshold, as a function of the body weight of rats, was calculated as 0.286μmoL/kg -1 . A dose of 1/5 of the seizure threshold dose primarily caused splayed limbs, posturing, and tremors of the entire body, whereas the dose of 1/10 of the seizure threshold dose caused agitation and shivering. A dose of 1/100 of the seizure threshold dose was associated with decreased locomotor activity. This study showed that rocuronium bromide has dose-related deleterious effects on the central nervous system and can produce dose-dependent excitatory effects and seizures. Publicado por Elsevier Editora Ltda.

  5. The effects of intra-cerebroventricular administered rocuronium on the central nervous system of rats and determination of its epileptic seizure-inducing dose.

    PubMed

    Baykal, Mehmet; Gökmen, Necati; Doğan, Alper; Erbayraktar, Serhat; Yılmaz, Osman; Ocmen, Elvan; Erdost, Hale Aksu; Arkan, Atalay

    The aim of this study was to investigate the effects of intracerebroventricularly administered rocuronium bromide on the central nervous system, determine the seizure threshold dose of rocuronium bromide in rats, and investigate the effects of rocuronium on the central nervous system at 1/5, 1/10, and 1/100 dilutions of the determined seizure threshold dose. A permanent cannula was placed in the lateral cerebral ventricle of the animals. The study was designed in two phases. In the first phase, the seizure threshold dose of rocuronium bromide was determined. In the second phase, Group R 1/5 (n=6), Group 1/10 (n=6), and Group 1/100 (n=6) were formed using doses of 1/5, 1/10, and 1/100, respectively, of the obtained rocuronium bromide seizure threshold dose. The rocuronium bromide seizure threshold value was found to be 0.056±0.009μmoL. The seizure threshold, as a function of the body weight of rats, was calculated as 0.286μmoL/kg -1 . A dose of 1/5 of the seizure threshold dose primarily caused splayed limbs, posturing, and tremors of the entire body, whereas the dose of 1/10 of the seizure threshold dose caused agitation and shivering. A dose of 1/100 of the seizure threshold dose was associated with decreased locomotor activity. This study showed that rocuronium bromide has dose-related deleterious effects on the central nervous system and can produce dose-dependent excitatory effects and seizures. Published by Elsevier Editora Ltda.

  6. Utility of bromide and heat tracers for aquifer characterization affected by highly transient flow conditions

    NASA Astrophysics Data System (ADS)

    Ma, Rui; Zheng, Chunmiao; Zachara, John M.; Tonkin, Matthew

    2012-08-01

    A tracer test using both bromide and heat tracers conducted at the Integrated Field Research Challenge site in Hanford 300 Area (300A), Washington, provided an instrument for evaluating the utility of bromide and heat tracers for aquifer characterization. The bromide tracer data were critical to improving the calibration of the flow model complicated by the highly dynamic nature of the flow field. However, most bromide concentrations were obtained from fully screened observation wells, lacking depth-specific resolution for vertical characterization. On the other hand, depth-specific temperature data were relatively simple and inexpensive to acquire. However, temperature-driven fluid density effects influenced heat plume movement. Moreover, the temperature data contained "noise" caused by heating during fluid injection and sampling events. Using the hydraulic conductivity distribution obtained from the calibration of the bromide transport model, the temperature depth profiles and arrival times of temperature peaks simulated by the heat transport model were in reasonable agreement with observations. This suggested that heat can be used as a cost-effective proxy for solute tracers for calibration of the hydraulic conductivity distribution, especially in the vertical direction. However, a heat tracer test must be carefully designed and executed to minimize fluid density effects and sources of noise in temperature data. A sensitivity analysis also revealed that heat transport was most sensitive to hydraulic conductivity and porosity, less sensitive to thermal distribution factor, and least sensitive to thermal dispersion and heat conduction. This indicated that the hydraulic conductivity remains the primary calibration parameter for heat transport.

  7. Chromatographic method for the determination of diazepam, pyridostigmine bromide, and their metabolites in rat plasma and urine.

    PubMed

    Abu-Qare, A W; Abou-Donia, M B

    2001-04-25

    This study describes a chromatographic method for the determination of diazepam, an anxiolytic drug that is also used as an antidote against nerve agent seizures, its metabolites N-desmethyldiazepam, and temazepam, the anti-nerve agent drug pyridostigmine bromide (PB; 3-dimethylaminocarbonyloxy-N-methyl pyridinium bromide) and its metabolite N-methyl-3-hydroxypyridinium bromide in rat plasma and urine. The compounds were extracted using C18 Sep-Pak Vac 3cc (500 mg) cartridges and separated using isocratic mobile phase of methanol, acetonitrile and water (pH 3.2) (10:40:50) at a flow-rate of 0.5 ml/min in a period of 12 min, and UV detection ranging between 240 and 280 nm. The limits of detection for all analytes ranged between 20 and 50 ng/ml, while limits of quantitation were 100 ng/ml. Average percentage extraction recoveries of five spiked plasma samples were 79.1+/-7.7, 83.5+/-6.4, 83.9+/-5.9, 71.3+/-6.0 and 77.7+/-5.6, and from urine 79.4+/-7.9, 83.1+/-6.9, 73.6+/-7.7, 74.3+/-7.1 and 77.6+/-5.9 for diazepam, N-desmethyldiazepam, temazepam, pyridostigmine bromide, and N-methyl-3-hydroxypyridinium bromide, respectively. The relationship between peak areas and concentration was linear over the range between 100 and 1000 ng/ml. This method was applied to determine the above analytes following a single oral administration in rats as a tool to study the pharmacokinetic profile of each compound, alone and in combination.

  8. Utility of Bromide and Heat Tracers for Aquifer Characterization Affected by Highly Transient Flow Conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ma, Rui; Zheng, Chunmiao; Zachara, John M.

    A tracer test using both bromide and heat tracers conducted at the Integrated Field Research Challenge site in Hanford 300 Area (300A), Washington, provided an instrument for evaluating the utility of bromide and heat tracers for aquifer characterization. The bromide tracer data were critical to improving the calibration of the flow model complicated by the highly dynamic nature of the flow field. However, most bromide concentrations were obtained from fully screened observation wells, lacking depth-specific resolution for vertical characterization. On the other hand, depth-specific temperature data were relatively simple and inexpensive to acquire. However, temperature-driven fluid density effects influenced heatmore » plume movement. Moreover, the temperature data contained “noise” caused by heating during fluid injection and sampling events. Using the hydraulic conductivity distribution obtained from the calibration of the bromide transport model, the temperature depth profiles and arrival times of temperature peaks simulated by the heat transport model were in reasonable agreement with observations. This suggested that heat can be used as a cost-effective proxy for solute tracers for calibration of the hydraulic conductivity distribution, especially in the vertical direction. However, a heat tracer test must be carefully designed and executed to minimize fluid density effects and sources of noise in temperature data. A sensitivity analysis also revealed that heat transport was most sensitive to hydraulic conductivity and porosity, less sensitive to thermal distribution factor, and least sensitive to thermal dispersion and heat conduction. This indicated that the hydraulic conductivity remains the primary calibration parameter for heat transport.« less

  9. A novel explicit approach to model bromide and pesticide transport in connected soil structures

    NASA Astrophysics Data System (ADS)

    Klaus, J.; Zehe, E.

    2011-07-01

    The present study tests whether an explicit treatment of worm burrows and tile drains as connected structures is feasible for simulating water flow, bromide and pesticide transport in structured heterogeneous soils at hillslope scale. The essence is to represent worm burrows as morphologically connected paths of low flow resistance in a hillslope model. A recent Monte Carlo study (Klaus and Zehe, 2010, Hydrological Processes, 24, p. 1595-1609) revealed that this approach allowed successful reproduction of tile drain event discharge recorded during an irrigation experiment at a tile drained field site. However, several "hillslope architectures" that were all consistent with the available extensive data base allowed a good reproduction of tile drain flow response. Our second objective was thus to find out whether this "equifinality" in spatial model setups may be reduced when including bromide tracer data in the model falsification process. We thus simulated transport of bromide for the 13 spatial model setups that performed best with respect to reproduce tile drain event discharge, without any further calibration. All model setups allowed a very good prediction of the temporal dynamics of cumulated bromide leaching into the tile drain, while only four of them matched the accumulated water balance and accumulated bromide loss into the tile drain. The number of behavioural model architectures could thus be reduced to four. One of those setups was used for simulating transport of Isoproturon, using different parameter combinations to characterise adsorption according to the Footprint data base. Simulations could, however, only reproduce the observed leaching behaviour, when we allowed for retardation coefficients that were very close to one.

  10. A novel explicit approach to model bromide and pesticide transport in soils containing macropores

    NASA Astrophysics Data System (ADS)

    Klaus, J.; Zehe, E.

    2011-01-01

    The present study tests whether an explicit treatment of worm burrows is feasible for simulating water flow, bromide and pesticide transport in structured heterogeneous soils. The essence is to represent worm burrows as morphologically connected paths of low flow resistance in the spatially highly resolved model domain. A recent Monte Carlo study (Klaus and Zehe, 2010) revealed that this approach allowed successful reproduction of tile drain event discharge recorded during an irrigation experiment at a tile drained field site. However, several "hillslope architectures" that were all consistent with the available extensive data base allowed a good reproduction of tile drain flow response. Our second objective was thus to find out whether this "equifinality" in spatial model setups may be reduced when including bromide tracer data in the model falsification process. We thus simulated transport of bromide and Isoproturon (IPU) for the 13 spatial model setups, which performed best with respect to reproduce tile drain event discharge, without any further calibration. All model setups allowed a very good prediction of the temporal dynamics of cumulated bromide leaching into the tile drain, while only four of them matched the accumulated water balance and accumulated bromide loss into the tile drain. The number of behavioural model architectures could thus be reduced to four. One of those setups was used for simulating transport of IPU, using different parameter combinations to characterise adsorption according to the Footprint data base. Simulations could, however, only reproduce the observed leaching behaviour, when we allowed for retardation coefficients that were very close to one.

  11. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Treatment 8 Hours or Less

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  12. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Treatment Longer than 8 Hours

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  13. Vinyl bromide

    Integrated Risk Information System (IRIS)

    Vinyl bromide ; CASRN 593 - 60 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vercher, E.; Pena, M.P.; Martinez-Andreu, A.

    Isobaric experimental data of vapor-liquid equilibrium for the ethanol-water-strontium bromide system at different mole fractions of strontium bromide have been measured at 100.6 kPa. Data were correlated by Jaques and Furter's method. Thermodynamic consistency was checked by Herington's method with satisfactory results.

  15. 7 CFR 319.74-2 - Conditions governing the entry of cut flowers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (insects of the family Agromyzidae) must be fumigated at the time of importation with methyl bromide in... consist of fumigation with methyl bromide at normal atmospheric pressure in a chamber or under a tarpaulin...

  16. 7 CFR 319.40-5 - Importation and entry requirements for specified articles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Christmas trees have been treated with methyl bromide to kill the pine shoot beetle; or, alternatively, in... certificate must indicate that the regulated articles have been treated with methyl bromide to kill the pine...

  17. 7 CFR 319.40-5 - Importation and entry requirements for specified articles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Christmas trees have been treated with methyl bromide to kill the pine shoot beetle; or, alternatively, in... certificate must indicate that the regulated articles have been treated with methyl bromide to kill the pine...

  18. Gulf War Illness Research Program

    DTIC Science & Technology

    2010-01-01

    will be exposed to pyridostigmine bromide , an antinerve agent drug, and the pesticides DEET and per- methrin, thought to be significant contribu...animal model further by combined exposure of DFP and stress hormone with chronic exposure to pyridostigmine bromide and DEET, two agents widely

  19. 77 FR 31564 - Notice of Availability of a Treatment Evaluation Document; Methyl Bromide Fumigation of Cottonseed

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-29

    ... significant impacts on U.S. cotton production. They are currently found only in Australia. Fumigation with methyl bromide was the only approved treatment for FOV VCG 01111 and 01112, so when the Environmental...

  20. Use of normal propyl bromide solvents for extraction and recovery of asphalt cements

    DOT National Transportation Integrated Search

    2000-11-01

    Four normal propyl bromide (nPB) solvents were evaluated for use as chlorinated solvent replacements in typical hot mix asphalt (HMA) extraction and recovery processes. The experimental design included one method of extraction (centrifuge), one metho...

  1. Scenario Analysis of the Impact on Drinking Water Intakes from Bromide in the Discharge of Treated Oil and Gas Wastewater

    EPA Pesticide Factsheets

    EPA scientists created different scenarios for conventional commercial wastewater treatment plants that treat oil and gas wastewaters to evaluate the impact from bromide in discharges by the CWTP plants.

  2. Temperature Dependence of Mineral Solubility in Water. Part 2. Alkaline and Alkaline Earth Bromides

    NASA Astrophysics Data System (ADS)

    Krumgalz, B. S.

    2018-03-01

    Databases of alkaline and alkaline earth bromide solubilities in water at various temperatures were created using experimental data from publications over about the last two centuries. Statistical critical evaluation of the created databases was produced since there were enough independent data sources to justify such evaluation. The reliable experimental data were adequately described by polynomial expressions over various temperature ranges. Using the Pitzer approach for ionic activity and osmotic coefficients, the thermodynamic solubility products for the discussed bromide minerals have been calculated at various temperature intervals and also represented by polynomial expressions.

  3. Breakdown of ionic character of molecular alkali bromides in inner-valence photoionization

    NASA Astrophysics Data System (ADS)

    Karpenko, A.; Iablonskyi, D.; Urpelainen, S.; Kettunen, J. A.; Cao, W.; Huttula, M.; Aksela, H.

    2014-05-01

    The inner-valence region of alkali bromide XBr (X=Li, Na, K, Rb) vapours has been studied experimentally by means of synchrotron radiation excited photoelectron spectroscopy. Experimental spectra were analyzed by comparing them with available theoretical results and previous experiments. Ionic character of alkali bromides is seen to change in the inner-valence region with increasing atomic number of the alkali atom. A mechanism involving mixing between Br 4s and Rb 4p orbitals has been suggested to account for the fine structure observed in inner-valence ionization region of RbBr.

  4. syn-Selective crotylation of aldehydes using bismuth-crotyl bromide-(1-butyl-3-methylimidazolium bromide) combination: some synthetic applications.

    PubMed

    Goswami, Dibakar; Koli, Mrunesh R; Chatterjee, Sucheta; Chattopadhyay, Subrata; Sharma, Anubha

    2017-05-03

    The Bi-[bmim][Br] combination has been found to offer high syn-selectivity in the crotylation of aldehydes with crotyl bromide using practically stoichiometric amounts of the reagents. The room temperature ionic liquid (RTIL), [bmim][Br], activated Bi metal in the presence of oxygen to produce crotylbismuthdibromide, which reacted with the aldehydes at room temperature. The major anti-syn diastereomeric product obtained from the crotylation of (R)-cyclohexylideneglyceraldehyde was utilized for the synthesis of dictyostatin and cryptophycin segments, and (+)-cis-aerangis lactone, using standard synthetic protocols.

  5. New Scintillator Materials (K2CeBr5) and (Cs2CeBr5)

    NASA Technical Reports Server (NTRS)

    Hawrami, R.; Volz, M. P.; Batra, A. K.; Aggarwal, M. D.; Roy, U. N.; Groza, M.; Burger, A.; Cherepy, Nerine; Niedermayr, Thomas; Payne, Stephen A.

    2008-01-01

    Cesium cerium bromide (Cs2CeBr5) and potassium cerium bromide (K2CeBr5) are new scintillator materials for X-ray and gamma ray detector applications. Recently halide scintillator materials, such as Ce doped lanthanum bromide has been proved to be very important material for the same purpose. These materials are highly hygroscopic; a search for high light yield non-hygroscopic materials was highly desirable to advance the scintillator technology. In this paper, we are reporting the crystal growth of novel scintillator materials, cesium cerium bromide (Cs2CeBr5) and potassium cerium bromide (K2CeBr5). Crystals were successfully grown from the melt using the vertical Bridgman-Stockbarger technique, in a comparison with the high performance LaBr3 or LaCl3 crystals, cerium based alkali halides crystals, (Cs2CeBr5) and (K2CeBr5) have similar scintillation properties, while being much less hygroscopic. Furthermore, cesium based compounds will not suffer from the self-activity present in potassium and lanthanum compounds. However the Cs2CeBr5 crystals did not grow properly probably due to non-congruent melting or to some phase transition during cooling. Keywords." Scintillator materials; Ce3+; Energy resolution; Light yield; K2CeBr5

  6. Study of the antibacterial and antifungal activities of synthetic benzyl bromides, ketones, and corresponding chalcone derivatives.

    PubMed

    Shakhatreh, Muhamad Ali K; Al-Smadi, Mousa L; Khabour, Omar F; Shuaibu, Fatima A; Hussein, Emad I; Alzoubi, Karem H

    2016-01-01

    Several applications of chalcones and their derivatives encouraged researchers to increase their synthesis as an alternative for the treatment of pathogenic bacterial and fungal infections. In the present study, chalcone derivatives were synthesized through cross aldol condensation reaction between 4-( N , N -dimethylamino)benzaldehyde and multiarm aromatic ketones. The multiarm aromatic ketones were synthesized through nucleophilic substitution reaction between 4-hydroxy acetophenone and benzyl bromides. The benzyl bromides, multiarm aromatic ketones, and corresponding chalcone derivatives were evaluated for their activities against eleven clinical pathogenic Gram-positive, Gram-negative bacteria, and three pathogenic fungi by the disk diffusion method. The minimum inhibitory concentration was determined by the microbroth dilution technique. The results of the present study demonstrated that benzyl bromide derivatives have strong antibacterial and antifungal properties as compared to synthetic chalcone derivatives and ketones. Benzyl bromides (1a and 1c) showed high ester activity against Gram-positive bacteria and fungi but moderate activity against Gram-negative bacteria. Therefore, these compounds may be considered as good antibacterial and antifungal drug discovery. However, substituted ketones (2a-b) as well as chalcone derivatives (3a-c) showed no activity against all the tested strains except for ketone (2c), which showed moderate activity against Candida albicans .

  7. Study of the antibacterial and antifungal activities of synthetic benzyl bromides, ketones, and corresponding chalcone derivatives

    PubMed Central

    Shakhatreh, Muhamad Ali K; Al-Smadi, Mousa L; Khabour, Omar F; Shuaibu, Fatima A; Hussein, Emad I; Alzoubi, Karem H

    2016-01-01

    Several applications of chalcones and their derivatives encouraged researchers to increase their synthesis as an alternative for the treatment of pathogenic bacterial and fungal infections. In the present study, chalcone derivatives were synthesized through cross aldol condensation reaction between 4-(N,N-dimethylamino)benzaldehyde and multiarm aromatic ketones. The multiarm aromatic ketones were synthesized through nucleophilic substitution reaction between 4-hydroxy acetophenone and benzyl bromides. The benzyl bromides, multiarm aromatic ketones, and corresponding chalcone derivatives were evaluated for their activities against eleven clinical pathogenic Gram-positive, Gram-negative bacteria, and three pathogenic fungi by the disk diffusion method. The minimum inhibitory concentration was determined by the microbroth dilution technique. The results of the present study demonstrated that benzyl bromide derivatives have strong antibacterial and antifungal properties as compared to synthetic chalcone derivatives and ketones. Benzyl bromides (1a and 1c) showed high ester activity against Gram-positive bacteria and fungi but moderate activity against Gram-negative bacteria. Therefore, these compounds may be considered as good antibacterial and antifungal drug discovery. However, substituted ketones (2a–b) as well as chalcone derivatives (3a–c) showed no activity against all the tested strains except for ketone (2c), which showed moderate activity against Candida albicans. PMID:27877017

  8. United States Department of Agriculture-Agricultural Research Service research on alternatives to methyl bromide: pre-plant and post-harvest.

    PubMed

    Schneider, Sally M; Rosskopf, Erin N; Leesch, James G; Chellemi, Daniel O; Bull, Carolee T; Mazzola, Mark

    2003-01-01

    Methyl bromide is a widely used fumigant for both pre-plant and post-harvest pest and pathogen control. The Montreal Protocol and the US Clean Air Act mandate a phase-out of the import and manufacture of methyl bromide, beginning in 2001 and culminating with a complete ban, except for quarantine and certain pre-shipment uses and exempted critical uses, in January 2005. In 1995, ARS built on its existing programs in soil-borne plant pathology and post-harvest entomology and plant pathology to initiate a national research program to develop alternatives to methyl bromide. The focus has been on strawberry, pepper, tomato, perennial and nursery cropping systems for pre-plant methyl bromide use and fresh and durable commodities for post-harvest use. Recently the program has been expanded to include research on alternatives for the ornamental and cut flower cropping systems. An overview of the national research program is presented. Results from four specific research trials are presented, ranging from organic to conventional systems. Good progress on short-term alternatives is being made. These will be used as the foundation of integrated management systems which begin with pre-plant management decisions and continue through post-harvest processing.

  9. Indium-mediated asymmetric barbier-type allylations: additions to aldehydes and ketones and mechanistic investigation of the organoindium reagents.

    PubMed

    Haddad, Terra D; Hirayama, Lacie C; Singaram, Bakthan

    2010-02-05

    We report a simple, efficient, and general method for the indium-mediated enantioselective allylation of aromatic and aliphatic aldehydes and ketones under Barbier-type conditions in a one-pot synthesis affording the corresponding chiral alcohol products in very good yield (up to 99%) and enantiomeric excess (up to 93%). Our method is able to tolerate various functional groups, such as esters, nitriles, and phenols. Additionally, more substituted allyl bromides, such as crotyl and cinnamyl bromide, can be used providing moderate enantioselectivity (72% and 56%, respectively) and excellent diastereoselectivity when employing cinnamyl bromide (>95/5 anti/syn). However, the distereoselectivity when using crotyl bromide was poor and other functionalized allyl bromides under our method afforded low enantioselectivities for the alcohol products. In these types of indium-mediated additions, solvent plays a major role in determining the nature of the organoindium intermediate and we observed the susceptibility of some allylindium intermediates to hydrolysis in protic solvents. Under our reaction conditions using a polar aprotic solvent, we suggest that an allylindium(III) species is the active allylating intermediate. In addition, we have observed the presence of a shiny, indium(0) nugget throughout the reaction, irrespective of the stoichiometry, indicating disproportionation of indium halide byproduct formed during the reaction.

  10. Nearly Perfect Triplet-Triplet Energy Transfer from Wannier Excitons to Naphthalene in Organic-Inorganic Hybrid Quantum-Well Materials

    NASA Astrophysics Data System (ADS)

    Ema, K.; Inomata, M.; Kato, Y.; Kunugita, H.; Era, M.

    2008-06-01

    We report the observation of extremely efficient energy transfer (greater than 99%) in an organic-inorganic hybrid quantum-well structure consisting of perovskite-type lead bromide well layers and naphthalene-linked ammonium barrier layers. Time-resolved photoluminescence measurements confirm that the transfer is triplet-triplet Dexter-type energy transfer from Wannier excitons in the inorganic well to the triplet state of naphthalene molecules in the organic barrier. Using measurements in the 10 300 K temperature range, we also investigated the temperature dependence of the energy transfer.

  11. A new and efficient synthetic method for 15N3-labeled cytosine nucleosides: Dimroth rearrangement of cytidine N3-oxides.

    PubMed

    Sako, Magoichi; Kawada, Hiroyoshi

    2004-11-12

    The treatment of (15)N(4)-labeled cytidine N(3)-oxide and (15)N(4)-labeled 2'-deoxycytidine N(3)-oxide, prepared from the appropriate unprotected uridines in three reaction steps, with benzyl bromide in the presence of excess lithium methoxide allowed the smooth occurrence of their Dimroth rearrangement even under mild conditions leading to the corresponding (15)N(3)-labeled uridine 4-O-benzyloximes which can easily undergo the reductive N-O bond cleavage to give the desirable (15)N(3)-labeled cytosine nucleosides in high total yields.

  12. Neuroinflammatory Pathobiology in Gulf War Illness: Characterization with an Animal Model

    DTIC Science & Technology

    2011-08-01

    evaluated alone and in combination (i.e. pyridostigmine bromide (PB), diethyl-m-toluamide (DEET), 5 lipopolysaccharide (LPS), corticosterone (CORT) and...acetylcholinesterase (AChE) inhibitor pyridostigmine bromide (PB), the insect repellent DEET and, potentially, the nerve agent, sarin. These combined

  13. Operate A Chemical Surety Program And Studies Supporting The Medical Chemical Defense Research Program

    DTIC Science & Technology

    2010-05-01

    23 Task Execution Plan 34 – Temperature Testing of Pyridostigmine Bromide (PB) .......... 23 KEY RESEARCH ACCOMPLISHMENTS...29, 2010. Staff was assembled and materials have been ordered. Task Execution Plan (TEP) 0034 – Temperature Testing of Pyridostigmine Bromide

  14. 40 CFR 180.123 - Inorganic bromide residues resulting from fumigation with methyl bromide; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Cantaloupe, postharvest 20.0 None Carrot, roots, postharvest 30.0 None Cashew, postharvest 200.0 None Cherry..., postharvest 20.0 None Nut, brazil, postharvest 200.0 None Nut, hickory, postharvest 200.0 None Nut, macadamia...

  15. 40 CFR 180.123 - Inorganic bromide residues resulting from fumigation with methyl bromide; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Cantaloupe, postharvest 20.0 None Carrot, roots, postharvest 30.0 None Cashew, postharvest 200.0 None Cherry..., postharvest 20.0 None Nut, brazil, postharvest 200.0 None Nut, hickory, postharvest 200.0 None Nut, macadamia...

  16. 40 CFR 180.123 - Inorganic bromide residues resulting from fumigation with methyl bromide; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Cantaloupe, postharvest 20.0 None Carrot, roots, postharvest 30.0 None Cashew, postharvest 200.0 None Cherry..., postharvest 20.0 None Nut, brazil, postharvest 200.0 None Nut, hickory, postharvest 200.0 None Nut, macadamia...

  17. BROMIDE'S EFFECT ON DBP FORMATION, SPECIATION, AND CONTROL: PART 1, OZONATION

    EPA Science Inventory

    The effect of variable ozone dosage and bromide concentration on the formation of organic disinfection byproducts (DBPs) and bromate were evaluated. Low ozone dosages resulted in oxidation of organic precursors, yielding decreases in the formation potential for total trihalometha...

  18. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Horizontal Stacks, 8 Hours or Less

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  19. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, No Stack, More than 8 Hours

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  20. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, No Stack, 8 Hours or Less

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  1. Pharmacodynamic Comparison of Rocuronium Bromide between Patients from the Plateau Area and from the Plain Area.

    PubMed

    Xie, Min; Huang, Jianxin; Li, Peng; Ou, Zhiyan; Hou, Jing

    2016-06-23

    We aimed to conduct a pharmacodynamic comparison of rocuronium bromide between patients from the plateau area and from the plain area. A total of 104 patients who received laparoscopic cholecystectomy in Sichuan Provincial People's Hospital and Aba Autonomous Prefecture People's Hospital from October 2015 to December 2015 were included in this study. Among them, 46 patients were from the plateau area and 58 were from the plain area. Both groups received total intravenous anesthesia (TIVA) with a dose of 0.6mg/kg rocuronium bromide during induction. In the meantime, neuromuscular block was monitored using a train-of-four (TOF) stimulation mode. The onset time (time to achieve the lowest TOF value after the injection of rocuronium bromide), duration of maximal neuromuscular block (duration of lowest T1 value), time to 25% recovery, time to 75% recovery, recovery index (time from 25% recovery to 75% recovery), time to extubation, length of stay in Post Anesthesia Care Unit (PACU) and muscle strength upon PACU discharge were all recorded. The onset time, time to 25% recovery, time to 75% recovery and time to extubation were all significantly prolonged in patients from the plateau area after receiving one single dose of rocuronium bromide (P<0.05). However, both groups didn't show any significant difference in maximal neuromuscular block, recovery index (time from 25% recovery to 75% recovery), length of stay in PACU or muscle strength upon PACU discharge (P>0.05). Compared to patients from the plain area, patients from the plateau area showed prolonged onset time of rocuronium bromide, reduced metabolic capabilities and longer duration of muscular relaxation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  2. The speciation of aqueous zinc(II) bromide solutions to 500 °C and 900 MPa determined using Raman spectroscopy

    USGS Publications Warehouse

    Mibe, Kenji; Chou, I-Ming; Anderson, Alan J.; Mayanovic, Robert A.; Bassett, William A.

    2009-01-01

    A Raman spectral study was carried out on 3 solutions of varying concentration and bromide/zinc ratios. Spectra were collected at 11 different temperature-pressure conditions ranging from ambient to 500????C-0.9??GPa. Raman band assignments for zinc(II) bromide species reported in previous studies were used to determine the relative concentrations of ZnBr42-, ZnBr3-, ZnBr2, and ZnBr+ species at various temperatures and pressures. Our results are in close agreement with X-ray absorption spectroscopic (XAS) data, and confirm that the tetrabromo zinc(II) complex, ZnBr42-, is the predominant species up to 500????C in solutions having high Zn concentrations (1??m) and high bromide/zinc molar ratios ([Br]/[Zn] = 8). In agreement with previous solubility and Raman spectroscopic experiments, our measurements indicate that species with a lower number of halide ligands and charge are favored with increasing temperature in dilute solutions, and solutions with low bromide/zinc ratios ([Br]/[Zn] < 2.5). The Raman technique provides an independent experimental means of evaluating the quality of XAS analyses of data obtained from high temperature disordered systems. The combination of these two techniques provides complementary data on speciation and the structure of zinc(II) bromide complexes. The preponderance of the ZnBr42- species in highly saline brines at high temperature is consistent with the predominance of ZnCl42- in chloride-rich brines reported in previous XAS studies. Knowledge of Zn complexing in metal-rich highly saline brines is important for numerical models of ore deposition in high temperature systems such as skarns and porphyry-type deposits. ?? 2008 Elsevier B.V.

  3. Four groups of new aromatic halogenated disinfection byproducts: effect of bromide concentration on their formation and speciation in chlorinated drinking water.

    PubMed

    Pan, Yang; Zhang, Xiangru

    2013-02-05

    Bromide is naturally present in source waters worldwide. Chlorination of drinking water can generate a variety of chlorinated and brominated disinfection byproducts (DBPs). Although substantial efforts have been made to examine the effect of bromide concentration on the formation and speciation of halogenated DBPs, almost all previous studies have focused on trihalomethanes and haloacetic acids. Given that about 50% of total organic halogen formed in chlorination remains unknown, it is still unclear how bromide concentration affects the formation and speciation of the new/unknown halogenated DBPs. In this study, chlorinated drinking water samples with different bromide concentrations were prepared, and a novel approach-precursor ion scan using ultra performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry-was adopted for the detection and identification of polar halogenated DBPs in these water samples. With this approach, 11 new putative aromatic halogenated DBPs were identified, and they were classified into four groups: dihalo-4-hydroxybenzaldehydes, dihalo-4-hydroxybenzoic acids, dihalo-salicylic acids, and trihalo-phenols. A mechanism for the formation of the four groups of new aromatic halogenated DBPs was proposed. It was found that increasing the bromide concentration shifted the entire polar halogenated DBPs as well as the four groups of new DBPs from being less brominated to being more brominated; these new aromatic halogenated DBPs might be important intermediate DBPs formed in drinking water chlorination. Moreover, the speciation of the four groups of new DBPs was modeled: the speciation patterns of the four groups of new DBPs well matched those determined from the model equations, and the reactivity differences between HOBr and HOCl in reactions forming the four groups of new DBPs were larger than those in reactions forming trihalomethanes and haloacetic acids.

  4. Intranasal Insulin: A Novel Treatment for Gulf War Multisymptom Illness

    DTIC Science & Technology

    2014-10-01

    Krengel M, Sullivan K. (2008). Neuropsychological Functioning in Gulf War veterans exposed to pesticides and pyridostigmine bromide . Fort Detrick, MD...Devine S, Heeren T, White RF. (2003). Cognitive functioning in treatment-seeking Gulf War veterans: pyridostigmine bromide use and PTSD. Journal of

  5. IDENTIFICATION OF NEW DRINKING WATER DISINFECTION BY-PRODUCTS FORMED IN THE PRESENCE OF BROMIDE

    EPA Science Inventory

    Using a combination of mass spectrometry and infrared spectroscopy, disinfection by-products (DBPs) were identified in ozonated drinking water containing elevated bromide levels, and in ozonated water treated with secondary chlorine or chloramine. Only one brominated by-product-d...

  6. REVIEW OF CONTROL OPTIONS FOR METHYL BROMIDE IN COMMODITY TREATMENT

    EPA Science Inventory

    The report describes recent developments in the control of methyl bromide (MeBr) and discusses technical considerations and requirements for and economic feasibility of recovery. (NOTE: MeBr, fumigant for agricultural commodities, is an ozone depleting chemical. The U.S. EPA has ...

  7. Ice Wedge Polygon Bromide Tracer Experiment in Subsurface Flow, Barrow, Alaska, 2015-2016

    DOE Data Explorer

    Nathan Wales

    2018-02-15

    Time series of bromide tracer concentrations at several points within a low-centered polygon and a high-centered polygon. Concentration values were obtained from the analysis of water samples via ion chromatography with an accuracy of 0.01 mg/l.

  8. Chemical alternatives to methyl bromide for Florida ornamental production

    USDA-ARS?s Scientific Manuscript database

    This project is a cooperative effort among USDA, ARS and University of Florida researchers, Florida in-ground ornamental producers, and fumigant industry representatives. Funding is provided through the USDA-ARS Area-wide Pest Management Program for Alternatives to Methyl Bromide. The ornamental i...

  9. Treatment of Dysphagia with Pyridostigmine Bromide in a Patient with the Pharyngeal-Cervical-Brachial Variant of Guillain-Barré Syndrome

    PubMed Central

    Lee, Kwang Lae; Lim, Oh Kyung; Park, Ki Deok

    2012-01-01

    A 24-year-old male developed bulbar palsy, ophthalmoplegia, ptosis, and shoulder weakness bilaterally 2 weeks after he had experienced an upper respiratory infection. The electrodiagnostic study demonstrated axonal polyradiculoneuropathy. The repetitive nerve stimulation study (RNS) showed no significant decrement of the compound muscle action potentials (CMAPs). The videofluoroscopic swallowing study (VFSS) showed severe impairment of the pharyngeal phase of swallowing. He was diagnosed as having the pharyngeal-cervical-brachial variant of Guillain-Barré syndrome. The patient's dysphagia was not improved for 3 months. A follow up RNS showed a significant decrement of the CMAPs. Pyridostigmine bromide was tried to improve the dysphagia. The patient showed immediate improvement of his dysphagia on the VFSS after the trial with pyridostigmine bromide. Pyridostigmine bromide was given before each meal for 8 days and he showed continuous improvement of his dysphagia. The follow up VFSS after 3 months showed complete recovery of dysphagia. PMID:22506249

  10. Treatment of Dysphagia with pyridostigmine bromide in a patient with the pharyngeal-cervical-brachial variant of guillain-barré syndrome.

    PubMed

    Lee, Kwang Lae; Lim, Oh Kyung; Lee, Ju Kang; Park, Ki Deok

    2012-02-01

    A 24-year-old male developed bulbar palsy, ophthalmoplegia, ptosis, and shoulder weakness bilaterally 2 weeks after he had experienced an upper respiratory infection. The electrodiagnostic study demonstrated axonal polyradiculoneuropathy. The repetitive nerve stimulation study (RNS) showed no significant decrement of the compound muscle action potentials (CMAPs). The videofluoroscopic swallowing study (VFSS) showed severe impairment of the pharyngeal phase of swallowing. He was diagnosed as having the pharyngeal-cervical-brachial variant of Guillain-Barré syndrome. The patient's dysphagia was not improved for 3 months. A follow up RNS showed a significant decrement of the CMAPs. Pyridostigmine bromide was tried to improve the dysphagia. The patient showed immediate improvement of his dysphagia on the VFSS after the trial with pyridostigmine bromide. Pyridostigmine bromide was given before each meal for 8 days and he showed continuous improvement of his dysphagia. The follow up VFSS after 3 months showed complete recovery of dysphagia.

  11. Highly Reactive, General and Long-Lived Catalysts for Palladium-Catalyzed Amination of Heteroaryl and Aryl Chlorides, Bromides and Iodides: Scope and Structure-Activity Relationships

    PubMed Central

    Shen, Qilong; Ogata, Tokutaro; Hartwig, John F.

    2010-01-01

    We describe a systematic study of the scope and relationship between ligand structure and activity for a highly efficient and selective class of catalysts for the amination of heteroaryl and aryl chlorides, bromides and iodides containing sterically hindered chelating alkylphosphines. In the presence of this catalyst, aryl and heteroaryl chlorides, bromides and iodides react with many primary amines in high yields with part-per-million quantities of palladium precursor and ligand. Many reactions of primary amines with both heteroaryl and aryl chlorides, bromides and iodides occur to completion with 0.0005-0.05 mol % catalysts. A comparison of the reactivity of this catalyst for coupling of primary amines at these loadings is made with catalysts generated from hindered monophosphines and carbenes, and these data illustrate the benefits of chelation. Thus, these complexes constitute a fourth-generation catalyst for the amination of aryl halides, whose activity complements catalysts based on monophosphines and carbenes. PMID:18444639

  12. Surface confined ionic liquid as a stationary phase for HPLC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Qian; Baker, Gary A; Baker, Sheila N

    Trimethoxysilane ionosilane derivatives of room temperature ionic liquids based on alkylimidazolium bromides were synthesized for attachment to silica support material. The derivatives 1-methyl-3-(trimethoxysilylpropyl)imidazolium bromide and 1-butyl-3-(trimethoxysilylpropyl)imidazolium bromide were used to modify the surface of 3 {micro}m diameter silica particles to act as the stationary phase for HPLC. The modified particles were characterized by thermogravimetric analysis (TGA) and {sup 13}C and {sup 29}Si NMR spectroscopies. The surface modification procedure rendered particles with a surface coverage of 0.84 {micro}mol m{sup -2} for the alkylimidazolium bromide. The ionic liquid moiety was predominantly attached to the silica surface through two siloxane bonds of themore » ionosilane derivative (63%). Columns packed with the modified silica material were tested under HPLC conditions. Preliminary evaluation of the stationary phase for HPLC was performed using aromatic carboxylic acids as model compounds. The separation mechanism appears to involve multiple interactions including ion exchange, hydrophobic interaction, and other electrostatic interactions.« less

  13. Improved phase stability of formamidinium lead triiodide perovskite by strain relaxation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zheng, Xiaojia; Wu, Congcong; Jha, Shikhar K.

    2016-10-18

    Though formamidinium lead triiodide (FAPbI 3) possesses a suitable band gap and good thermal stability, the phase transition from the pure black perovskite phase (α-phase) to the undesirable yellow nonperovskite polymorph (δ-phase) at room temperature, especially under humid air, hinders its practical application. Here, we investigate the intrinsic instability mechanism of the α-phase at ambient temperature and demonstrate the existence of an anisotropic strained lattice in the (111) plane that drives phase transformation into the δ-phase. Methylammonium bromide (MABr) alloying (or FAPbI 3-MABr) was found to cause lattice contraction, thereby balancing the lattice strain. This led to dramatic improvement inmore » the stability of α-FAPbI 3. As a result, solar cells fabricated using FAPbI 3-MABr demonstrated significantly enhanced stability under the humid air.« less

  14. Coal resources of New Mexico

    USGS Publications Warehouse

    Read, Charles Brian; Duffner, R.T.; Wood, G.H.; Zapp, A.D.

    1950-01-01

    A study of water quality degradation due to brine contamination was made in an area of about 1,700 sq mi in east-central Oklahoma. The study area coincides in part with the outcrop of the Vamoosa-Ada aquifer of Pennsylvanian age. Water samples collected from 180 wells completed in the Vamoosa-Ada aquifer and at 167 sites from streams draining the Vamoosa-Ada aquifer show scattered occurrences of water quality degradation by brine. Degradation of water quality by brine is indicated where: (1) chloride concentration is > or = to 400 mg/L; (2) bromide concentration is > or = 2 mg/L; (3) the ratio of sodium plus chloride to dissolved solids is > or = 0.64. Ratios of secondary importance that also indicate water quality degradation by brine in the area are: (1) a ratio of lithium to bromide < or = 0.01, when the chloride concentration is > or = 400 mg/L; (2) a sodium/chloride ratio of about 0.46; (3) a sodium/bromide ratio of about 92; and (4) a bromide/chloride ratio of about 0.0048. Values for bromide, lithium, strontium, dissolved solids, calcium, magnesium, sodium, chloride, and sulfate concentrations were subjected to analysis of variance based on use of the index values in partition data sets. The analysis of variance showed the significance of the indexes for all constituents except sulfate. The two most reliable brine indicators are chloride and bromide. Statistically, chloride is a slightly more reliable index than bromide. The developed indexes can be used to indicate water quality degradation by brine. Accuracy is improved if both indexes are used. When geophysical logs from 133 pairs of oil and gas wells were analyzed, data from 5 pairs of wells indicated a possible rise in the interface between fresh water and salt water in the Vamoosa-Ada aquifer. Therefore , any rise of the interface is local rather than regional. The criteria developed in this study indicate that brine has degraded water quality at 63 sites on streams draining the Vamoosa-Ada aquifer, at 15 water wells completed in the Vamoosa-Ada aquifer, and at 5 oil and gas wells penetrating the Vamoosa-Ada aquifer. (Author 's abstract)

  15. Observations of Chemical Composition in Frost Flower Growth Process and Their Implication in Aerosol Production and Bromine Activation Chemistry

    NASA Astrophysics Data System (ADS)

    Alvarez-Aviles, L.; Simpson, W. R.; Douglas, T. A.; Sturm, M.; Perovich, D. K.

    2006-12-01

    Frost flowers are believed to be responsible for most of the salt aerosol and possibly the bromine in the gas phase during springtime in Polar Regions. Frost flowers are vapor deposited ice crystals that form on new forming sea ice and wick brine from the sea-ice surface resulting in high salinities. We propose a conceptual model of frost flower growth and chemical fractionation using chemical analysis to support this model. We also consider how the chemical composition of frost flowers can tell us about the role of frost flowers in bromine activation and aerosol production. Our conceptual model is centered in two important events that occur when sea ice grows and the ice surface temperature gets colder. Brine on the sea-ice surface is drawn up the frost flower by capillary forces, therefore the high salinity values found. Secondarily salt hydrates begin to precipitate at certain temperatures. These precipitation reactions modify the chemical composition of the frost flowers and residual brine, and are the main topic of this research. We found variability and generally depletion of sulfate as compared to sea-water composition in most of the mature frost flowers. This result is in agreement with the literature, which proposes the depletion in sulfate occurs because mirabilite (Na2SO4 · 10H2O) precipitates before the brine is wicked. The observation of some slightly sulfate-enhanced samples in addition to depleted samples indicates that the brine/frost flower environment is the location where mirabilite precipitation and separation from residual brine occurs. Frost flowers bromide enhancement factors are all, within analytical limits, identical to sea water, although nearby snow is depleted in bromide. Because of the high salt concentrations in frost flowers, significant bromine activation could occur from frost flowers without being detected by this measurement. However, if all bromide activation occurred on frost flowers, and frost flowers are not depleted in bromide, no snow would be found that was depleted in bromide. Therefore, the observation of snow that is depleted in bromide shows there must be some activation of bromide subsequent to frost flowers formation.

  16. Spectrophotometric estimation of bromide ion in excess chloride media.

    PubMed

    Adimurthy, S; Susarla, V R K S; Reddy, M P; Ramachandraiah, G

    2005-10-31

    The redox reaction between bromate and chloride ions in the presence and the absence of two or less equivalents of bromide ion ascertaining the formation of bromine chloride species of type BrCl and BrCl(2)(-) in subsequent reactions in 4% H(2)SO(4), has been studied by spectrophotometry. Calibration graphs for the bromide ion estimation in 0.1% KBrO(3)-4% H(2)SO(4) medium are determined separately in the presence of known amounts of NaCl. The effect of Cl(-) ion percentage on the determination of Br(-) ion is studied and reported herewith a suitable equation for a precise, reliable and quick spectrophotometric estimation.

  17. Combined blood cell counting and classification with fluorochrome stains and flow instrumentation.

    PubMed

    Shapiro, H M; Schildkraut, E R; Curbelo, R; Laird, C W; Turner, B; Hirschfeld, T

    1976-01-01

    A multiparameter flow cytophotometer was used to count and classify fixed human blood cells fluorochromed with a mixture of ethidium bromide (EB), brilliant sulfaflavine and a blue fluorescent stilbene disulfonic acid derivative (LN). The system measures light scattered by the cells and absorption at 420 nm for all cells. In addition, nuclear EB fluorescence (540 leads to 610 nm) and cytoplasmic fluorescence from LN (366 leads to 470 nm), brilliant sulfaflavine (420 leads to 520 nm) and EB exicted by energy transfer from LN (366 leads to 610 nm) are measured for all nucleated cells. This information is sufficient to perform red and white blood cell counts and to classify leukocytes as lymphocytes, monocytes, basophils, eosinophils or neutrophils. Light scattering and/or nuclear and cytoplasmic fluorescence values may be further analyzed to obtain the ratio of immature to mature neutrophils. Counts produced by the system are in reasonable agreement with those obtained by electronic cells counting and examination of Wright's-stained blood smears; some discrepancies appear to be due to systematic errors in the manual counting method.

  18. Intrinsic and Extrinsic Stability of Formamidinium Lead Bromide Perovskite Solar Cells Yielding High Photovoltage.

    PubMed

    Arora, Neha; Dar, M Ibrahim; Abdi-Jalebi, Mojtaba; Giordano, Fabrizio; Pellet, Norman; Jacopin, Gwénolé; Friend, Richard H; Zakeeruddin, Shaik Mohammed; Grätzel, Michael

    2016-11-09

    We report on both the intrinsic and the extrinsic stability of a formamidinium lead bromide [CH(NH 2 ) 2 PbBr 3 = FAPbBr 3 ] perovskite solar cell that yields a high photovoltage. The fabrication of FAPbBr 3 devices, displaying an outstanding photovoltage of 1.53 V and a power conversion efficiency of over 8%, was realized by modifying the mesoporous TiO 2 -FAPbBr 3 interface using lithium treatment. Reasons for improved photovoltaic performance were revealed by a combination of techniques, including photothermal deflection absorption spectroscopy (PDS), transient-photovoltage and charge-extraction analysis, and time-integrated and time-resolved photoluminescence. With lithium-treated TiO 2 films, PDS reveals that the TiO 2 -FAPbBr 3 interface exhibits low energetic disorder, and the emission dynamics showed that electron injection from the conduction band of FAPbBr 3 into that of mesoporous TiO 2 is faster than for the untreated scaffold. Moreover, compared to the device with pristine TiO 2 , the charge carrier recombination rate within a device based on lithium-treated TiO 2 film is 1 order of magnitude lower. Importantly, the operational stability of perovskites solar cells examined at a maximum power point revealed that the FAPbBr 3 material is intrinsically (under nitrogen) as well as extrinsically (in ambient conditions) stable, as the unsealed devices retained over 95% of the initial efficiency under continuous full sun illumination for 150 h in nitrogen and dry air and 80% in 60% relative humidity (T = ∼60 °C). The demonstration of high photovoltage, a record for FAPbBr 3 , together with robust stability renders our work of practical significance.

  19. Effects of conventional ozonation and electro-peroxone pretreatment of surface water on disinfection by-product formation during subsequent chlorination.

    PubMed

    Mao, Yuqin; Guo, Di; Yao, Weikun; Wang, Xiaomao; Yang, Hongwei; Xie, Yuefeng F; Komarneni, Sridhar; Yu, Gang; Wang, Yujue

    2018-03-01

    The electro-peroxone (E-peroxone) process is an emerging ozone-based electrochemical advanced oxidation process that combines conventional ozonation with in-situ cathodic hydrogen peroxide (H 2 O 2 ) production for oxidative water treatment. In this study, the effects of the E-peroxone pretreatment on disinfection by-product (DBP) formation from chlorination of a synthetic surface water were investigated and compared to conventional ozonation. Results show that due to the enhanced transformation of ozone (O 3 ) to hydroxyl radicals (OH) by electro-generated H 2 O 2 , the E-peroxone process considerably enhanced dissolved organic carbon (DOC) abatement and significantly reduced bromate (BrO 3 - ) formation compared to conventional ozonation. However, natural organic matter (NOM) with high UV 254 absorbance, which is the major precursors of chlorination DBPs, was less efficiently abated during the E-peroxone process than conventional ozonation. Consequently, while both conventional ozonation and the E-peroxone process substantially reduced the formation of DBPs (trihalomethanes and haloacetic acids) during post-chlorination, higher DBP concentrations were generally observed during chlorination of the E-peroxone pretreated waters than conventional ozonation treated. In addition, because of conventional ozonation or the E-peroxone treatment, DBPs formed during post-chlorination shifted to more brominated species. The overall yields of brominated DBPs exhibited strong correlations with the bromide concentrations in water. Therefore, while the E-peroxone process can effectively suppress bromide transformation to bromate, it may lead to higher formation of brominated DBPs during post-chlorination compared to conventional ozonation. These results suggest that the E-peroxone process can lead to different DBP formation and speciation during water treatment trains compared to conventional ozonation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Physicochemical characterization of epigallocatechin gallate lipid nanoparticles (EGCG-LNs) for ocular instillation.

    PubMed

    Fangueiro, Joana F; Andreani, Tatiana; Fernandes, Lisete; Garcia, Maria L; Egea, Maria A; Silva, Amélia M; Souto, Eliana B

    2014-11-01

    The encapsulation of epigallocatechin gallate (EGCG) in lipid nanoparticles (LNs) could be a suitable approach to avoid drug oxidation and epimerization, which are common processes that lead to low bioavailability of the drug limiting its therapeutic efficacy. The human health benefits of EGCG gained much interest in the pharmaceutical field, and so far there are no studies reporting its encapsulation in LNs. The purpose of this study has been the development of an innovative system for the ocular delivery of EGCG using LNs as carrier for the future treatment of several diseases, such as dry eye, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy and macular oedema. LNs dispersions have been produced by multiple emulsion technique and previously optimized by a factorial design. In order to increase ocular retention time and mucoadhesion by electrostatic attraction, two distinct cationic lipids were used, namely, cetyltrimethylammonium bromide (CTAB) and dimethyldioctadecylammonium bromide (DDAB). EGCG has been successfully loaded in the LNs dispersions and the nanoparticles analysis over 30 days of storage time predicted a good physicochemical stability. The particles were found to be in the nanometer range (<300 nm) and all the evaluated parameters, namely pH, osmolarity and viscosity, were compatible to the ocular administration. The evaluation of the cationic lipid used was compared regarding physical and chemical parameters, lipid crystallization and polymorphism, and stability of dispersion during storage. The results show that different lipids lead to different characteristics mainly associated with the acyl chain composition, i.e. double lipid shows to have influence in the crystallization and stability. Despite the recorded differences between DTAB and DDAB, both cationic LNs seem to fit the parameters for ocular drug delivery. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Attached Vertical Stacks, More than 8 hours, 10 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  2. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Attached Vertical Stacks , 8 Hours or Less, 10 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  3. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Attached Vertical Stacks, 8 Hours or Less, 50 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  4. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Attached Vertical Stacks , 8 Hours or Less, 25 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  5. BROMATE-INDUCED TRANSCRIPTIONAL CHANGES IN LONG-EVANS RAT KIDNEYS

    EPA Science Inventory


    Bromate-Induced Transcriptional Changes in Long-Evans Rat Kidneys.

    Ozone disinfection of surface waters containing bromide ion (Br-) results in the oxidation of bromide to bromate, which can be found in finished drinking water as a by-product. Potassium bromate (KBrO3)...

  6. 77 FR 35295 - Methyl Bromide; Pesticide Tolerances

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    .... SUMMARY: This regulation establishes a tolerance for residues of methyl bromide in or on cotton... on cotton, undelinted seed at 150 parts per million (ppm). EPA issued a proposed rule that explained... were accurate. According to USDA, drought conditions in Texas have reduced cotton production by 13...

  7. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Attached Vertical Stacks, More than 8 hours, 25 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  8. CHLORPYRIFOS TRANSFORMATION BY AQUEOUS CHLORINE IN THE PRESENCE OF BROMIDE AND NATURAL ORGANIC MATTER

    EPA Science Inventory

    The aqueous chlorination of chlorpyrifos (CP) was investigated in the presence of bromide and natural organic matter (NOM), which were identified as naturally occurring aqueous constituents that could impact CP transformation rates to the toxic product chlorpyrifos oxon (CPO). Br...

  9. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Attached Vertical Stacks, More than 8 hours, 50 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  10. Bromine substitution improves excited-state dynamics in mesoporous mixed halide perovskite films.

    PubMed

    Talbert, Eric M; Zarick, Holly F; Boulesbaa, Abdelaziz; Soetan, Naiya; Puretzky, Alexander A; Geohegan, David B; Bardhan, Rizia

    2017-08-24

    In this study, ultrafast transient absorption spectroscopy (TAS) is utilized to examine the excited-state dynamics in methylammonium lead iodide/bromide (MAPb(I 1-x Br x ) 3 ) perovskites as a function of bromide content. TAS spectral behavior reveals characteristic lifetimes for thermalization, recombination, and charge carrier injection of MAPb(I 1-x Br x ) 3 from x = 0 to 0.3 infiltrated in mesoporous titania films. Carrier recombination and charge injection lifetimes demonstrated a discernable increase with Br content likely because high carrier populations are supported by the higher density of vacant electronic states in mixed-halide perovskites due to the increased capacity of the conduction band. However, we observe for the first time that carrier thermalization lifetimes significantly decrease with increasing Br. This suggests that the shift in crystal structure from tetragonal towards pseudocubic accelerates carrier cooling, resulting in the relief of the hot phonon bottleneck. Furthermore, the stabilized MAPb(I 1-x Br x ) 3 samples exhibit a lower Burstein-Moss shift of 0.07-0.08 eV compared to pure MAPbI 3 (0.12 eV). Our results provide evidence that Br inclusion contributes to a broadening of the parabolic conduction band and to improvement in electron-phonon coupling and phonon propagation in the lattice.

  11. Bromine substitution improves excited-state dynamics in mesoporous mixed halide perovskite films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Talbert, Eric M.; Zarick, Holly F.; Boulesbaa, Abdelaziz

    Here in this study, ultrafast transient absorption spectroscopy (TAS) is utilized to examine the excited-state dynamics in methylammonium lead iodide/bromide (MAPb(I 1-xBrx)3) perovskites as a function of bromide content. TAS spectral behavior reveals characteristic lifetimes for thermalization, recombination, and charge carrier injection of MAPb(I 1-xBr x) 3 from x = 0 to 0.3 infiltrated in mesoporous titania films. Carrier recombination and charge injection lifetimes demonstrated a discernable increase with Br content likely because high carrier populations are supported by the higher density of vacant electronic states in mixed-halide perovskites due to the increased capacity of the conduction band. However, wemore » observe for the first time that carrier thermalization lifetimes significantly decrease with increasing Br. This suggests that the shift in crystal structure from tetragonal towards pseudocubic accelerates carrier cooling, resulting in the relief of the hot phonon bottleneck. Furthermore, the stabilized MAPb(I 1-xBrx) 3 samples exhibit a lower Burstein–Moss shift of 0.07–0.08 eV compared to pure MAPbI 3 (0.12 eV). Our results provide evidence that Br inclusion contributes to a broadening of the parabolic conduction band and to improvement in electron–phonon coupling and phonon propagation in the lattice.« less

  12. Primula auriculata Extracts Exert Cytotoxic and Apoptotic Effects against HT-29 Human Colon Adenocarcinoma Cells

    PubMed Central

    Behzad, Sahar; Ebrahim, Karim; Mosaddegh, Mahmoud; Haeri, Ali

    2016-01-01

    Primula auriculata (Tootia) is one of the most important local medicinal plants in Hamedan district, Iran. To investigate cytotoxicity and apoptosis induction of crude methanolic extract and different fraction of it, we compared several methods on HT-29 human colon Adenocarcinoma cells. Cancer cell proliferation was measured by 3-(4, 5‑dimethylthiazolyl)2, 5‑diphenyl‑tetrazolium bromide (MTT) assay and apoptosis induction was analyzed by fluorescence microscopy (acridin orange/ethidium bromide, annexin V/propidium iodide staining, TUNEL assay and Caspase-3 activity assay). Crude methanolic extract (CM) inhibited the growth of malignant cells in a dose-dependent manner. Among solvent fractions, the dichloromethane fraction (CF) was found to be the most toxic compared to other fractions. With double staining methods, high percentage of 40 µg/mL of (CM) and (CF) treated cells exhibited typical characteristics of apoptotic cells. Apoptosis induction was also revealed by apoptotic fragmentation of nuclear DNA and activation of caspas-3 in treated cells. These findings indicate that crude methanolic extract and dichloromethan fraction of P.auriculata induced apoptosis and inhibited proliferation in colon cancer cells and could be used as a source for new lead structures in drug design to combat colon cancer. PMID:27610172

  13. Extremely Low Operating Current Resistive Memory Based on Exfoliated 2D Perovskite Single Crystals for Neuromorphic Computing.

    PubMed

    Tian, He; Zhao, Lianfeng; Wang, Xuefeng; Yeh, Yao-Wen; Yao, Nan; Rand, Barry P; Ren, Tian-Ling

    2017-12-26

    Extremely low energy consumption neuromorphic computing is required to achieve massively parallel information processing on par with the human brain. To achieve this goal, resistive memories based on materials with ionic transport and extremely low operating current are required. Extremely low operating current allows for low power operation by minimizing the program, erase, and read currents. However, materials currently used in resistive memories, such as defective HfO x , AlO x , TaO x , etc., cannot suppress electronic transport (i.e., leakage current) while allowing good ionic transport. Here, we show that 2D Ruddlesden-Popper phase hybrid lead bromide perovskite single crystals are promising materials for low operating current nanodevice applications because of their mixed electronic and ionic transport and ease of fabrication. Ionic transport in the exfoliated 2D perovskite layer is evident via the migration of bromide ions. Filaments with a diameter of approximately 20 nm are visualized, and resistive memories with extremely low program current down to 10 pA are achieved, a value at least 1 order of magnitude lower than conventional materials. The ionic migration and diffusion as an artificial synapse is realized in the 2D layered perovskites at the pA level, which can enable extremely low energy neuromorphic computing.

  14. High Resolution Direct Frequency Comb Spectroscopy of Vinyl Bromide (C_2H_3Br) and Nitromethane (CH_3NO_2) in the CH Stretch Region

    NASA Astrophysics Data System (ADS)

    Changala, Bryan; Spaun, Ben; Patterson, David; Ye, Jun

    2016-06-01

    We present high resolution rovibrational spectra of buffer gas cooled vinyl bromide (C_2H_3Br) and nitromethane (CH_3NO_2) in the 3 μm CH stretch region, acquired via cavity-enhanced direct frequency comb absorption spectroscopy. The ˜10 K translational and rotational temperatures of the molecular gas, as well as the narrow linewidth of the frequency comb, yield well resolved rotational structure, isotope shifts, and nuclear hyperfine splittings. Given the wide bandwidth of the light source and the long path length of the enhancement cavity, we measure entire vibrational bands in a single shot with high signal-to-noise ratios. We discuss spectra of the entire fundamental CH stretch manifolds of both C_2H_3Br and CH_3NO_2, which provide contrasting examples of rovibrational structure of rigid and non-rigid systems. C_2H_3Br is a relatively normal asymmetric top, exhibiting local perturbations to its rotational structure. Conversely, CH_3NO_2 contains an essentially unhindered methyl rotor. Of particular interest are its quasi-degenerate asymmetric CH stretch modes. Here, one must consider multiple couplings between torsional, rotational, and vibrational angular momentum, leading to qualitatively new level patterns and structure.

  15. Bromine substitution improves excited-state dynamics in mesoporous mixed halide perovskite films

    DOE PAGES

    Talbert, Eric M.; Zarick, Holly F.; Boulesbaa, Abdelaziz; ...

    2017-08-02

    Here in this study, ultrafast transient absorption spectroscopy (TAS) is utilized to examine the excited-state dynamics in methylammonium lead iodide/bromide (MAPb(I 1-xBrx)3) perovskites as a function of bromide content. TAS spectral behavior reveals characteristic lifetimes for thermalization, recombination, and charge carrier injection of MAPb(I 1-xBr x) 3 from x = 0 to 0.3 infiltrated in mesoporous titania films. Carrier recombination and charge injection lifetimes demonstrated a discernable increase with Br content likely because high carrier populations are supported by the higher density of vacant electronic states in mixed-halide perovskites due to the increased capacity of the conduction band. However, wemore » observe for the first time that carrier thermalization lifetimes significantly decrease with increasing Br. This suggests that the shift in crystal structure from tetragonal towards pseudocubic accelerates carrier cooling, resulting in the relief of the hot phonon bottleneck. Furthermore, the stabilized MAPb(I 1-xBrx) 3 samples exhibit a lower Burstein–Moss shift of 0.07–0.08 eV compared to pure MAPbI 3 (0.12 eV). Our results provide evidence that Br inclusion contributes to a broadening of the parabolic conduction band and to improvement in electron–phonon coupling and phonon propagation in the lattice.« less

  16. Re-manufacture of cobalt-manganese-bromide as a liquid catalyst from spent catalyst containing cobalt generated from petrochemical processes via hydrometallurgy.

    PubMed

    Joo, Sung-Ho; Shin, Dong Ju; Oh, Chang Hyun; Wang, Jei-Pil; Shin, Shun Myung

    2016-11-15

    Cobalt and manganese have been the subject of individual separation studies because their fields of application are different. However, this study shows that high-value products can be manufactured in the form of a cobalt-manganese-bromide (CMB) liquid catalyst by simultaneously recovering cobalt and manganese. Na-bis-(2,4,4-tri-methyl-pentyl)phosphinic acid was employed in order to manufacture the CMB liquid catalyst from the spent catalyst generated from petroleum chemistry processes. The pH-isotherm, degree of saponification of solvent and separation factor values were investigated. ΔpH50 and separation factor values show that Co and Mn can be separated from impurities such as Mg and Ca. Further, the extraction stages and organic/aqueous ratio isotherms were investigated using counter-current simulation extraction batch tests. To prepare CMB from a loaded organic phase obtained in a stripping study using hydrogen bromide, the Co and Mn were completely stripped and concentrated by a factor of 6 using a 2M hydrogen bromide solution. When compared with manufactured and commercial CMB, the CMB liquid catalyst could be produced by supplying a shortage of Mn in the form of manganese bromide. Finally, the method of manufacture of CMB was subjected to a real pilot plant test. Copyright © 2016. Published by Elsevier B.V.

  17. Analysis of genotoxic activity of ketamine and rocuronium bromide using the somatic mutation and recombination test in Drosophila melanogaster.

    PubMed

    Koksal, Pakize Muge; Gürbüzel, Mehmet

    2015-03-01

    The present study evaluated the mutagenic and recombinogenic effects of two commonly used anesthetic agents, ketamine and rocuronium bromide, in medicine using the wing somatic mutation and recombination test (SMART) in Drosophila. The standard (ST) cross and the high-bioactivation (HB) cross with high sensitivity to procarcinogens and promutagens were used. The SMART test is based on the loss of heterozygosity, which occurs via various mechanisms, such as chromosome loss and deletion, half-translocation, mitotic recombination, mutation, and non-disjunction. Genetic alterations occurring in the somatic cells of the wing's imaginal discs result in mutant clones in the wing blade. Three-day-old trans-heterozygous larvae with two recessive markers, multiple wing hairs (mwh) and flare (flr(3)), were treated with ketamine and rocuronium bromide. Analysis of the ST cross indicated that ketamine exhibited genotoxicity activity and that this activity was particularly dependent on homologous mitotic recombination at concentrations of 250 μg/ml and above. Rocuronium bromide did not exert mutagenic and/or recombinogenic effects. In the HB cross, ketamine at a concentration of 1000 μg/ml and rocuronium bromide at all concentrations, with the exception of 250 μg/ml (inconclusive), exerted genotoxic effects, which could also be associated with the increase in mitotic recombination. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Oral Mucosal Injection of a Local Anesthetic Solution Containing Epinephrine Enhances Muscle Relaxant Effects of Rocuronium

    PubMed Central

    Ninomiya, Asako; Terakawa, Yui; Matsuura, Nobuyuki; Ichinohe, Tatsuya; Kaneko, Yuzuru

    2012-01-01

    The purpose of this study was to examine how submucosal injection of a clinically relevant dose of a lidocaine hydrochloride solution containing epinephrine affects the muscle relaxant effects of rocuronium bromide. Sixteen patients scheduled for orthognathic surgery participated in this study. All patients were induced with fentanyl citrate, a target-controlled infusion of propofol and rocuronium bromide. Anesthesia was maintained by total intravenous anesthesia. After nasotracheal intubation, an infusion of rocuronium bromide was started at 7 µg/kg/min, and the infusion rate was then adjusted to maintain a train of four (TOF) ratio at 10 to 15%. The TOF ratio just prior to oral mucosal injection of a 1% lidocaine hydrochloride solution containing 10 µg/mL epinephrine (LE) was taken as the baseline. TOF ratio was observed for 20 minutes, with 1-minute intervals following the start of injection. Mean epinephrine dose was 85.6 ± 18.6 µg and mean infusion rate of rocuronium bromide was 6.3 ± 1.6 µg/kg/min. TOF ratio began to decrease 2 minutes after the injection of LE, reached the minimum value at 3.1 ± 3.6% 12 minutes after the injection, and then began to recover. We conclude that oral mucosal injection of LE enhances the muscle relaxant effects of rocuronium bromide. PMID:22428970

  19. Predictive models for water sources with high susceptibility for bromine-containing disinfection by-product formation: implications for water treatment.

    PubMed

    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.

  20. Bromide, Chloride, and Sulfate Concentrations and Loads at U.S. Geological Survey Streamflow-Gaging Stations 07331600 Red River at Denison Dam, 07335500 Red River at Arthur City, and 07336820 Red River near DeKalb, Texas, 2007-09

    USGS Publications Warehouse

    Baldys, Stanley; Churchill, Christopher J.; Mobley, Craig A.; Coffman, David K.

    2010-01-01

    The U.S. Geological Survey, in cooperation with the City of Dallas Water Utilities Division, did a study to characterize bromide, chloride, and sulfate concentrations and loads at three U.S. Geological Survey streamflow-gaging stations on the reach of the Red River from Denison Dam, which impounds Lake Texoma, to the U.S. Highway 259 bridge near DeKalb, Texas. Bromide, chloride, and sulfate concentrations and loads were computed for streamflow-gaging stations on the study reach of the Red River. Continuous streamflow and specific conductance data and discrete samples for bromide, chloride, sulfate, and specific conductance were collected at three main-stem streamflow-gaging stations on the Red River: 07331600 Red River at Denison Dam near Denison, Texas (Denison Dam gage), 07335500 Red River at Arthur City, Texas (Arthur City gage), and 07336820 Red River near DeKalb, Texas (DeKalb gage). At each of these streamflow-gaging stations, discrete water-quality data were collected during January 2007-February 2009; continuous water-quality data were collected during March 2007-February 2009. Two periods of high flow resulted from floods during the study; floods during June-July 2007 resulted in elevated flow during June-September 2007 and smaller floods during March-April 2008 resulted in elevated flow during March-April 2008. Bromide, chloride, and sulfate concentrations in samples collected at the three gages decreased downstream. Median bromide concentrations ranged from 0.32 milligram per liter at the Denison Dam gage to 0.19 milligram per liter at the DeKalb gage. Median chloride concentrations ranged from 176 milligrams per liter at the Denison Dam gage to 108 milligrams per liter at the DeKalb gage, less than the 300-milligrams per liter secondary maximum contaminant level established by the Texas Commission on Environmental Quality. Median sulfate concentrations ranged from 213 milligrams per liter at the Denison Dam gage to 117 milligrams per liter at the DeKalb gage, also less than the 300-milligrams per liter secondary maximum contaminant level. Kruskal-Wallis analyses indicated statistically significant differences among bromide, chloride, and sulfate concentrations at the three gages. Regression equations to estimate bromide, chloride, and sulfate loads were developed for each of the three gages. The largest loads were estimated for a period of relatively large streamflow, June-September 2007, when about 50 percent of the load for the study period occurred at each gage. Adjusted R-squared values were largest for regression equations for the DeKalb gage, ranging from .957 for sulfate to .976 for chloride. Adjusted R-squared values for all regression equations developed to estimate loads of bromide, chloride, and sulfate at the three gages were .899 or larger.

  1. Ninety-Day Subchronic Oral Toxicity Study of Pyridostigmine Bromide in Rats. Volume 1

    DTIC Science & Technology

    1990-05-01

    myasthenia gravis because of its relative lack of untoward effects in comparison with other anticholinesterases (2). This relative lack of clinical...treatment of myasthenia gravis . Objecrive of Study The objective of this study was to determine the 90-day subchronic toxicity of pyridostigmine bromide in

  2. 77 FR 48153 - Protection of Stratospheric Ozone: Request for Methyl Bromide Critical Use Exemption Applications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-13

    ... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OAR-2012-0375, FRL-9715-7] Protection of Stratospheric Ozone: Request for Methyl Bromide Critical Use Exemption Applications for 2015, Deadline Extension... Stratospheric Ozone Information Hotline, 1-800-296-1996; also http://www.epa.gov/ozone/mbr . Technical...

  3. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks, More than 8 Hours, 25 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  4. Steam disinfestation as a methyl bromide alternative in California cut flower nurseries

    USDA-ARS?s Scientific Manuscript database

    Steam may be an effective alternative to methyl bromide in cut flower production in California. Advantages of steam include broad spectrum pest control and a zero hour re-entry interval. The principle disadvantage of sheet steaming is cost effectiveness due to current energy prices and application...

  5. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks , 8 Hours or Less, 5 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  6. Intranasal Insulin: A Novel Treatment for Gulf War Multisymptom Illness

    DTIC Science & Technology

    2015-10-01

    exposed to pesticides and pyridostigmine bromide . Fort Detrick, MD: US Army Medical Research and Material Command. Li B, Mahan CM, Kang HK, Eisen SA...War veterans: pyridostigmine bromide use and PTSD. Journal of Psychopathology and Behavioral Assessment. 25(2):95-103. Tillman GD, Green TA, Ferree

  7. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks, More than 8 Hours, 5 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  8. Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters

    EPA Science Inventory

    Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired power plants, conventional oil and gas extraction, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. ...

  9. Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters - slides

    EPA Science Inventory

    Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired powerplants, conventional oil and gas extraction, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. W...

  10. Thallium bromide radiation detectors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shah, K.S.; Lund, J.C.; Olschner, F.

    1989-02-01

    Radiation detectors have been fabricated from crystals of the semiconductor material thallium bromide (TlBr) and the performance of these detectors as room temperature photon spectrometers has been measured. These detectors exhibit improved energy resolution over previously reported TlBr detectors. These results indicate that TlBr is a very promising radiation detector material.

  11. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks, 8 Hours or Less, 10 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  12. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks, 8 Hours or Less, 50 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  13. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks, 8 Hours or Less, 25 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  14. TRIBROMOPYRROLE, BROMINATED ACIDS, AND OTHER DISINFECTION BYPRODUCTS PRODUCED BY DISINFECTION OF DRINKING WATER RICH IN BROMIDE

    EPA Science Inventory

    Using gas chromatography/mass spectrometry (GC/MS), we investigated the formation of disinfection byproducts (DBPs) from high bromide waters (2 mg/L) treated with chlorine or chlorine dioxide used in combination with chlorine and chloramines. This study represents the first comp...

  15. 40 CFR 721.4090 - Ethanaminium, N-[bis(diethylamino)-methylene]-N-ethyl-, bromide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Ethanaminium, N-[bis(diethylamino)-methylene]-N-ethyl-, bromide. 721.4090 Section 721.4090 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.4090 Ethanaminium, N-[bis(diethylamino)-methylene]-N...

  16. GTE_TRACEP_P3B Parameters 1

    Atmospheric Science Data Center

    2013-02-19

    ... Methyl bromide (CH3Br) Bromopropane (C3H7 Br) Methyl Chloride (CH3Cl) Ethyl Chloride (C2H5Cl) Vinyl chloride (C2H3Cl) ... Trichloroethylene (C2HCl3) Tetrachloroethylene (C2Cl4) Methylene bromide (CH2Br2) Chlorodibromomethane (CHClBr2) Bromoform ...

  17. GTE_TRACEP_DC8 Parameters 4

    Atmospheric Science Data Center

    2013-02-18

    ... Methyl bromide (CH3Br) Bromopropane (C3H7Br) Methyl Chloride(CH3Cl) Ethyl Chloride (C2H5Cl) Vinyl chloride (C2H3Cl) ... Trichloroethylene (C2HCl3) Tetrachloroethylene (C2Cl4) Methylene bromide (CH2Br2) Chlorodibromomethane(CHClBr2) Bromoform ...

  18. Evaluation of non-fumigant pesticides as methyl bromide alternatives for managing weeds in vegetables

    USDA-ARS?s Scientific Manuscript database

    The phase out of methyl bromide challenged vegetable growers’ abilities to control weeds in low-density polyethylene (LDPE) mulch production systems. The herbicides halosulfuron, fomesafen, s-metolachlor, and clomazone are needed as part of the pesticide program in LDP vegetable production to contr...

  19. 21 CFR 178.1010 - Sanitizing solutions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... permanganate (CAS Reg. No. 7722-64-7). Magnesium oxide (CAS Reg. No. 1309-48-4) and potassium bromide (CAS Reg... permanganate. (ii) The solution identified in paragraph (b)(37) of this section with potassium bromide shall... potassium permanganate. (iii) Magnesium oxide when used in paragraph (c)(32) (i) or (ii) of this section...

  20. Palladium-Catalyzed Conversion of Aryl and Vinyl Triflates to Bromides and Chlorides

    PubMed Central

    Shen, Xiaoqiang; Hyde, Alan M.; Buchwald, Stephen L.

    2010-01-01

    The palladium-catalyzed conversion of aryl and vinyl triflates to aryl and vinyl halides (bromides and chlorides) has been developed using dialkylbiaryl phosphine ligands. A variety of aryl, heteroaryl and vinyl halides can be prepared via this method in good to excellent yields. PMID:20857936

  1. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks, More than 8 Hours, 50 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  2. Methyl Bromide Buffer Zone Distances for Commodity and Structural Fumigation: Active Aeration, Open Area Vertical Stacks, More than 8 Hours, 10 Foot Stack Height

    EPA Pesticide Factsheets

    This document contains buffer zone tables required by certain methyl bromide commodity fumigant product labels that refer to Buffer Zone Lookup Tables located at epa.gov/pesticide-registration/mbcommoditybuffer on the label.

  3. 40 CFR 721.4090 - Ethanaminium, N-[bis(diethylamino)-methylene]-N-ethyl-, bromide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Ethanaminium, N-[bis(diethylamino)-methylene]-N-ethyl-, bromide. 721.4090 Section 721.4090 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.4090 Ethanaminium, N-[bis(diethylamino)-methylene]-N...

  4. Methyl bromide phase out could affect future reforestation efforts

    USDA-ARS?s Scientific Manuscript database

    Methyl bromide has long been an integral component in producing healthy tree seedlings in forest nurseries of California, Idaho, Montana, Oregon and Washington. The fumigant was supposed to be completely phased out of use in the United States of America by 2005, but many forest nurseries continue to...

  5. Discharges of produced waters from oil and gas extraction via wastewater treatment plants are sources of disinfection by-products to receiving streams

    USGS Publications Warehouse

    Hladik, Michelle; Focazio, Michael J.; Engle, Mark

    2014-01-01

    Fluids co-produced with oil and gas production (produced waters) are often brines that contain elevated concentrations of bromide. Bromide is an important precursor of several toxic disinfection by-products (DBPs) and the treatment of produced water may lead to more brominated DBPs. To determine if wastewater treatment plants that accept produced waters discharge greater amounts of brominated DBPs, water samples were collected in Pennsylvania from four sites along a large river including an upstream site, a site below a publicly owned wastewater treatment plant (POTW) outfall (does not accept produced water), a site below an oil and gas commercial wastewater treatment plant (CWT) outfall, and downstream of the POTW and CWT. Of 29 DBPs analyzed, the site at the POTW outfall had the highest number detected (six) ranging in concentration from 0.01 to 0.09 μg L− 1 with a similar mixture of DBPs that have been detected at POTW outfalls elsewhere in the United States. The DBP profile at the CWT outfall was much different, although only two DBPs, dibromochloronitromethane (DBCNM) and chloroform, were detected, DBCNM was found at relatively high concentrations (up to 8.5 μg L− 1). The water at the CWT outfall also had a mixture of inorganic and organic precursors including elevated concentrations of bromide (75 mg L− 1) and other organic DBP precursors (phenol at 15 μg L− 1). To corroborate these DBP results, samples were collected in Pennsylvania from additional POTW and CWT outfalls that accept produced waters. The additional CWT also had high concentrations of DBCNM (3.1 μg L− 1) while the POTWs that accept produced waters had elevated numbers (up to 15) and concentrations of DBPs, especially brominated and iodinated THMs (up to 12 μg L− 1 total THM concentration). Therefore, produced water brines that have been disinfected are potential sources of DBPs along with DBP precursors to streams wherever these wastewaters are discharged.

  6. On the stereochemical course of palladium-catalyzed cross-coupling of allylic silanolate salts with aromatic bromides.

    PubMed

    Denmark, Scott E; Werner, Nathan S

    2010-03-17

    The stereochemical course of palladium-catalyzed cross-coupling reactions of an enantioenriched, alpha-substituted, allylic silanolate salt with aromatic bromides has been investigated. The allylic silanolate salt was prepared in high geometrical (Z/E, 94:6) and high enantiomeric (94:6 er) purity by a copper-catalyzed S(N)2' reaction of a resolved allylic carbamate. Eight different aromatic bromides underwent cross-coupling with excellent constitutional site-selectivity and excellent stereospecificity. Stereochemical correlation established that the transmetalation event proceeds through a syn S(E)' mechanism which is interpreted in terms of an intramolecular delivery of the arylpalladium electrophile through a key intermediate that contains a discrete Si-O-Pd linkage.

  7. Direct Observation Of Nanoparticle-Surfactant Interactions Using Small Angle Neutron Scattering

    NASA Astrophysics Data System (ADS)

    Kumar, Sugam; Aswal, V. K.

    2010-12-01

    Interactions of anionic silica nanoparticles with anionic, cationic and nonionic surfactants have directly been studied by contrast variation small angle neutron scattering (SANS). The measurements are performed on 1 wt% of both silica nanoparticles and surfactants of anionic sodium dodecyle sulphate (SDS), cationic dodecyltrimethyl ammonium bromide (DTAB) and non-ionic polyoxyethylene 10 lauryl ether (C12E10) in aqueous solution. We show that there is no direct interaction in the case of SDS with silica particles, whereas strong interaction for DTAB leads to the aggregation of silica particles. The interaction of C12E10 is found through the micelles adsorbed on the silica particles.

  8. Optically pumped lasing and electroluminescence of formamidinium perovskite semiconductors prepared by the cast-capping method

    NASA Astrophysics Data System (ADS)

    Sasaki, Fumio; Nguyen, Van-Cao; Yanagi, Hisao

    2018-03-01

    Optically pumped lasing and electroluminescence (EL) have been observed in solution-processed perovskite semiconducting materials of formamidinium lead bromide, CH(NH2)2PbBr3. Microcavities with flat surfaces and sharp edges have been easily obtained by the simple solution process called the “cast-capping method”. The crystals show clear multimode lasing of Fabry-Pérot cavities. The mode intervals are well explained by the optical constants with large dispersions of the materials. We have also fabricated EL devices and obtained clear EL in a single layer of the materials, but the EL intensity has been quenched rapidly.

  9. Characterization of polylactic co-glycolic acid nanospheres modified with PVA and DDAB

    NASA Astrophysics Data System (ADS)

    Mulia, Kamarza; Satyapertiwi, Dwiantari; Devina, Ranee; Krisanti, Elsa

    2017-02-01

    The common treatment for diabetic retinopathy is corticosteroids intravitreal injection that sometimes lead to complications. Dexamethasone-loaded polylactic co-glycolic acid (PLGA) nanospheres, modified with dioctadecyldimethylammonium bromide (DDAB) as the cationic surfactant, is expected to prolong drug retention time. Zeta potential of the PLGA nanospheres prepared using non-ionic surfactant PVA and DDAB confirmed the cationic surfactant increase the surface charge of the PLGA nanospheres. The optimal formulation based on the particle size and high positive surface charge was the PLGA-DDAB nanospheres. SEM analysis showed spherical morphology of the nanospheres having diameter 626.9 ± 98.01 nm positive zeta potential of +22.5 mV.

  10. Enhanced Optical and Electrical Properties of Polymer-Assisted All-Inorganic Perovskites for Light-Emitting Diodes.

    PubMed

    Ling, Yichuan; Tian, Yu; Wang, Xi; Wang, Jamie C; Knox, Javon M; Perez-Orive, Fernando; Du, Yijun; Tan, Lei; Hanson, Kenneth; Ma, Biwu; Gao, Hanwei

    2016-10-01

    Highly bright light-emitting diodes based on solution-processed all-inorganic perovskite thin film are demonstrated. The cesium lead bromide (CsPbBr 3 ) created using a new poly(ethylene oxide)-additive spin-coating method exhibits photoluminescence quantum yield up to 60% and excellent uniformity of electrical current distribution. Using the smooth CsPbBr 3 films as emitting layers, green perovskite-based light-emitting diodes (PeLEDs) exhibit electroluminescent brightness and efficiency above 53 000 cd m -2 and 4%: a new benchmark of device performance for all-inorganic PeLEDs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Halonium ion-assisted deiodination of styrene-based vicinal iodohydrins followed by rearrangement through phenyl migration.

    PubMed

    Agrawal, Manoj K; Ghosh, Pushpito K

    2009-10-16

    Acid activation of bromate/bromide couple at 0-10 degrees C was found to trigger the deiodination of styrene-based vicinal iodohydrins. Violet coloration of the organic layer was ascribed to formation of IBr. Deiodination was followed by phenyl migration and deprotonation leading to formation of phenyl acetone and 2-phenylpropanal in good yields from 1-iodo-2-phenylpropan-2-ol and 2-iodo-1-phenylpropan-1-ol, respectively. Phenyl acetaldehyde--which was obtained in 92% GC yield from styrene iodohydrin--was also presumably formed in analogous manner. NBS and HOCl too were effective for transformation of styrene iodohydrin into phenyl acetaldehyde.

  12. Presence of chemical additives and microbial inhibition capacity in grapefruit seed extracts used in apiculture.

    PubMed

    Spinosi, Valerio; Semprini, Primula; Langella, Vincenzo; Scortichini, Giampiero; Calvarese, Silvano

    2007-01-01

    American foulbrood, caused by Paenibacillus larvae subsp. larvae (White 1906) is one of the most serious diseases of honey bees, causing beekeepers and health workers to make difficult, complex decisions and leading to the development of 'organic' treatments, such as grapefruit seed extract, with minor residue problems in the end product. This study evaluates the chemical composition of grapefruit seed extracts using gas chromatography/mass spectrometry for the detection of benzethonium chloride, cetrimonium bromide and decyltrimethylammonium chloride. The results obtained suggest a close correlation between the microbial effect and the presence of chemical additives in the samples analysed.

  13. Samuel Wilks (1824-1911): neurologist and generalist of the Mid-Victorian Era.

    PubMed

    Eadie, Mervyn J

    2008-11-01

    Sir Samuel Wilks, sometime Physician to Guy's Hospital and President of the Royal College of Physicians (1896-99), was regarded as the leading British scientific physician of his day. His contributions to gastroenterology, cardiology and clinical science in general have been emphasized in recent times. He also recognized that syphilis affected the internal organs as well as the skin. In 1866 he realised that epileptogenesis occurred in the cerebral cortex: independently of Sir Charles Locock (1799-1875), he discovered the antiepileptic properties of potassium bromide. He provided possibly the first account of alcoholic peripheral neuritis and published an early account of probable myasthenia gravis.

  14. Methyl bromide release from activated carbon and the soil/water/carbon interface

    USDA-ARS?s Scientific Manuscript database

    Methyl Bromide (MB) is a major source of stratospheric bromine radical, a known depletor of ozone. The use of ozone-depleting chemicals, including MB, is regulated by the Montreal Protocol. Critical uses of MB are permitted, such as when postharvest fumigation is mandated by an importing country. Fo...

  15. Successes and failures in controlling weeds in hardwood seedbeds at the Arkansas Forestry Commission Baucum Forest Nursery

    Treesearch

    Allan Murray

    2009-01-01

    Fumigation with methyl bromide is essential in the production of hardwood seedlings in nurseries in the southern United States. However, the proposed rules under the 2008 U.S. Environmental Protection Agency (EPA) Risk Mitigation will further restrict the use of methyl bromide for nursery use.

  16. Optimizing postharvest methyl bromide treatments to control spotted wing drosophila, Drosophila suzukii, in sweet cherries from Western USA

    USDA-ARS?s Scientific Manuscript database

    Methyl bromide (MB) chamber fumigations were evaluated for postharvest control of spotted wing drosophila (SWD), Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), in fresh sweet cherry exports from Western USA. Sweet cherries were infested with SWD, incubated to maximize numbers of the most M...

  17. The use of agricultural by-products to capture methyl bromide following post-harvest fumigation

    USDA-ARS?s Scientific Manuscript database

    Activated carbons were prepared from plum and peach stone as well as almond and walnut shell and comparatively evaluated as sorbents to minimize the atmospheric emission of methyl bromide following postharvest fumigations. A variety of methods were used to make the activated carbons and each is desc...

  18. OZONATION BYPRODUCTS: IDENTIFICATION OF BROMOHYDRINS FROM THE OZONATION OF NATURAL WATERS WITH ENHANCED BROMIDE LEVELS

    EPA Science Inventory

    When ozone is used in the treatment of drinking water, it reacts with both inorganic and organic compounds to form byproducts. f bromide is present, it may be oxidized to hydrobromous acid, which may than react with natural organic matter to form brominated organic compounds. he ...

  19. Weed Control in Bareroot Hardwood Nurseries

    Treesearch

    David B. South; William A. Carey

    2005-01-01

    Managers in the southern United States rely on chemical and non-chemical methods of weed control. Chemical treatments include fumigation with methyl bromide and chloropicrin in combination with selective herbicides. If methyl bromide is no longer produced in the future, the amount of handweeding will likely increase unless managers adapt to the change. Some nursery...

  20. EVALUATION OF CONTAINMENT AND CONTROL OPTIONS FOR METHYL BROMIDE IN COMMODITY TREATMENT

    EPA Science Inventory

    The report gives results of an investigation of means for methyl bromide (MeBr) recovery, reuse, and destruction to prevent atmospheric emissions if its limited use were still allowed. (NOTE: MeBr is an ozone-depleting chemical scheduled to be phased out by the Clean Air Act by t...

  1. Iron-catalyzed cross-coupling of N-heterocyclic chlorides and bromides with arylmagnesium reagents.

    PubMed

    Kuzmina, Olesya M; Steib, Andreas K; Flubacher, Dietmar; Knochel, Paul

    2012-09-21

    A simple, practical iron salt catalyzed procedure allows fast cross-couplings of N-heterocyclic chlorides and bromides with various electron-rich and -poor arylmagnesium reagents. A solvent mixture of THF and tBuOMe is found to be essential for achieving high yields mainly by avoiding homocoupling side reactions.

  2. Effect of bromide in a surface water intake on the formation of brominated trihalomethanes at a public water system treatment plant

    EPA Science Inventory

    This project is a collaborative drinking water research study. EPA is evaluating water samples collected by PWS operators in order to investigate relationships between bromide in source water and the formation of brominated DBPs in finished drinking water. This study will includ...

  3. 78 FR 36507 - Notice of Availability of a Treatment Evaluation Document; Methyl Bromide Fumigation of Blueberries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-18

    ...] Notice of Availability of a Treatment Evaluation Document; Methyl Bromide Fumigation of Blueberries... blueberries for Mediterranean fruit fly and South American fruit fly. We have prepared a treatment evaluation... at neutralizing these fruit flies. We are making the treatment evaluation document available to the...

  4. Effects Of Haloacetic Acid Mixtures in a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) Assay

    EPA Science Inventory

    The haloacetic acids (HAAs) are a class of chemicals produced as byproducts of drinking water disinfection. Source water characteristics (such as level of bromide) affects which HAAs are present in drinking water and their concentration. For example, high bromide-source water wil...

  5. 40 CFR 180.3 - Tolerances for related pesticide chemicals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... grown on methyl bromide-treated soil and also fumigated with methyl bromide after harvest is 300 parts...-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide). Endosulfan sulfate (6,7,8,9,10,10-hexachloro-1,5,5a... p-chlorobenzenesulfonate). Sesone (sodium 2,4-dichlorophenoxyethyl sulfate, SES). Sodium 2,4...

  6. 76 FR 23449 - Citrus Canker, Citrus Greening, and Asian Citrus Psyllid; Interstate Movement of Regulated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-27

    ... conditions, the articles are treated with methyl bromide and shipped in a container that has been sealed with... of any regulated article, including citrus nursery stock, provided that: The article is treated with methyl bromide in accordance with 7 CFR part 305. That part contains our phytosanitary treatment...

  7. 7 CFR 301.50-10 - Treatments and management method.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... be treated with methyl bromide at normal atmospheric pressure with 48 g/m3 (3 lb/1000 ft3) for 16... garlands. Cut pine Christmas trees and raw pine materials for pine wreaths and garlands may be treated with methyl bromide at normal atmospheric pressure as follows: Temperature Dosage: pounds per 1000 feet 3...

  8. 40 CFR 180.3 - Tolerances for related pesticide chemicals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... grown on methyl bromide-treated soil and also fumigated with methyl bromide after harvest is 300 parts...-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide). Endosulfan sulfate (6,7,8,9,10,10-hexachloro-1,5,5a... p-chlorobenzenesulfonate). Sesone (sodium 2,4-dichlorophenoxyethyl sulfate, SES). Sodium 2,4...

  9. 75 FR 41177 - Protection of Stratospheric Ozone: Request for Methyl Bromide Critical Use Exemption Applications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-15

    ... this will be the state's agriculture or environmental protection agency) to receive information about.... Government (through EPA, Department of State, U.S. Department of Agriculture, and other interested Federal... baseline year, the U.S. consumption was approximately 25,500 metric tons of methyl bromide. In 2010, the...

  10. Movements of water, solutes, and stable isotopes in the unsaturated zones of two sand plains in the upper Midwest

    USGS Publications Warehouse

    Komor, Stephen C.; Emerson, Douglas G.

    1994-01-01

    Four month-long field experiments investigated movements of water and solutes through unsaturated sand plains near Princeton, Minnesota, and Oakes, North Dakota. Atrazine and bromide were applied to bare soils and soils planted with corn. The field plots were irrigated according to local farming practices. At the end of each experiment, unsaturated soils were analyzed for atrazine and bromide concentrations and oxygen and hydrogen isotope compositions of soil water. Most soil water was affected by evaporation but groundwater beneath the plots had no evaporative isotopic signature. Therefore most recharge consisted of water that was unaffected by evaporation. Sources of such water may have included snowmelt, prolonged or high-intensity rainfalls that were not interrupted by periods of drying, and water that moved through preferential flow paths. Preferential flow also was suggested by the detection of atrazine, deethylatrazine, and bromide in groundwater shortly after each application of irrigation water at Princeton and by isolated concentrations of atrazine and bromide in soil well below the main masses of chemicals at Oakes.

  11. Leisingera methylohalidivorans gen. nov., sp. nov., a marine methylotroph that grows on methyl bromide

    USGS Publications Warehouse

    Schaefer, J.K.; Goodwin, K.D.; McDonald, I.R.; Murrell, J.C.; Oremland, R.S.

    2002-01-01

    A marine methylotroph, designated strain MB2T, was isolated for its ability to grow on methyl bromide as a sole carbon and energy source. Methyl chloride and methyl iodide also supported growth, as did methionine and glycine betaine. A limited amount of growth was observed with dimethyl sulfide. Growth was also noted with unidentified components of the complex media marine broth 2216, yeast extract and Casamino acids. No growth was observed on methylated amines, methanol, formate, acetate, glucose or a variety of other substrates. Growth on methyl bromide and methyl iodide resulted in their oxidation to CO2 with stoichiometric release of bromide and iodide, respectively. Strain MB2T exhibited growth optima at NaCl and Mg2+ concentrations similar to that of seawater. Phylogenetic analysis of the 16S rDNA sequence placed this strain in the ??-Proteobacteria in proximity to the genera Ruegeria and Roseobacter. It is proposed that strain MB2T (= ATCC BAA-92T = DSM 14336T) be designated Leisingera methylohalidivorans gen. nov., sp. nov.

  12. Room temperature synthesis of silver nanowires from tabular silver bromide crystals in the presence of gelatin

    NASA Astrophysics Data System (ADS)

    Liu, Suwen; Wehmschulte, Rudolf J.; Lian, Guoda; Burba, Christopher M.

    2006-03-01

    Long silver nanowires were synthesized at room temperature by a simple and fast process derived from the development of photographic films. A film consisting of an emulsion of tabular silver bromide grains in gelatin was treated with a photographic developer (4-(methylamino)phenol sulfate (metol), citric acid) in the presence of additional aqueous silver nitrate. The silver nanowires have lengths of more than 50 μm, some even more than 100 μm, and average diameters of about 80 nm. Approximately, 70% of the metallic silver formed in the reduction consists of silver nanowires. Selected area electron diffraction (SAED) results indicate that the silver nanowires grow along the [111] direction. It was found that the presence of gelatin, tabular silver bromide crystals and silver ions in solution are essential for the formation of the silver nanowires. The nanowires appear to originate from the edges of the silver bromide crystals. They were characterized by transmission electron microscopy (TEM), SAED, scanning electron microscopy (SEM), and powder X-ray diffraction (XRD).

  13. Room temperature synthesis of silver nanowires from tabular silver bromide crystals in the presence of gelatin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu Suwen; Wehmschulte, Rudolf J.; Lian Guoda

    2006-03-15

    Long silver nanowires were synthesized at room temperature by a simple and fast process derived from the development of photographic films. A film consisting of an emulsion of tabular silver bromide grains in gelatin was treated with a photographic developer (4-(methylamino)phenol sulfate (metol), citric acid) in the presence of additional aqueous silver nitrate. The silver nanowires have lengths of more than 50 {mu}m, some even more than 100 {mu}m, and average diameters of about 80 nm. Approximately, 70% of the metallic silver formed in the reduction consists of silver nanowires. Selected area electron diffraction (SAED) results indicate that the silvermore » nanowires grow along the [111] direction. It was found that the presence of gelatin, tabular silver bromide crystals and silver ions in solution are essential for the formation of the silver nanowires. The nanowires appear to originate from the edges of the silver bromide crystals. They were characterized by transmission electron microscopy (TEM), SAED, scanning electron microscopy (SEM), and powder X-ray diffraction (XRD)« less

  14. Methyl bromide fumigation and delayed mortality: safe trade of live pests?

    PubMed

    Phillips, C B; Iline, I I; Novoselov, M; McNeill, M R; Richards, N K; van Koten, C; Stephenson, B P

    Live organisms intercepted from treated commodities during phytosanitary inspections usually arouse suspicions of treatment failure, sub-standard treatment application, or post-treatment infestation. The additional possibility that some treatments could kill slowly, meaning commodities might be inspected before pests have succumbed, is seldom considered for treatments other than irradiation. We used a novel biochemical viability assay to measure delays between methyl bromide fumigation and mortality of dipteran eggs, and evaluated the correspondence between egg viability and egg morphological features. Our experimental conditions simulated shipping of rock melons from Australia to New Zealand by sea and air. No eggs survived fumigation, but they took 3-20 days to die, whereas phytosanitary inspections of rock melons occur within 2-7 days. Delays were not influenced by methyl bromide concentration, but were significantly lengthened by cooler storage temperatures. Methyl bromide's preservative effects delayed degradation of egg morphology, so the biochemical assay detected mortality long before morphological signs of egg death appeared. The results show that commodities subjected to effective methyl bromide treatments are at risk of being inspected before all pests have either died, or started to exhibit morphological signs of death. This could cause commodities to be unnecessarily rejected by quarantine authorities. Better methods than inspection for live pests are needed to assist authorities to gain assurance that treated commodities have been effectively disinfested. These could be developed by exploiting biochemical responses of pests and commodities to treatments.

  15. Development of a high-performance liquid chromatographic method for the quantification of chlorpyrifos, pyridostigmine bromide, N,N-diethyl-m-toluamide and their metabolites in rat plasma and urine.

    PubMed

    Abu-Qare, A W; Abou-Donia, M B

    2001-04-25

    A method was developed for the separation and quantification of the insecticide chlorpyrifos (O,O-diethyl-O[3,5,6-trichloro-2-pyridinyl] phosphorothioate), its metabolites chlorpyrifos-oxon (O,O-diethyl-O[3,5,6-trichloro-2-pyridinyl] phosphate) and TCP (3,5,6-trichloro-2-pyridinol), the anti-nerve agent drug pyridostigmine bromide (PB; 3-dimethylaminocarbonyloxy-N-methyl pyridinium bromide), its metabolite N-methyl-3-hydroxypyridinium bromide, the insect repellent DEET (N,N-diethyl-m-toluamide), and its metabolites m-toluamide and m-toluic acid in rat plasma and urine. The method is based on using solid-phase extraction and high-performance liquid chromatography (HPLC) with reversed-phase C18 column, and gradient UV detection ranging between 210 and 280 nm. The compounds were separated using a gradient of 1-85% acetonitrile in water (pH 3.20) at a flow-rate ranging between 1 and 1.7 ml/min over a period of 15 min. The retention times ranged from 5.4 to 13.2 min. The limits of detection ranged between 20 and 150 ng/ml, while the limits of quantitation were between 150 and 200 ng/ml. Average percentage recovery of five spiked plasma samples was 80.2+/-7.9, 74.9+/-8.5, 81.7+/-6.9, 73.1+/-7.8, 74.3+/-8.3, 80.8+/-6.6, 81.6+/-7.3 and 81.4+/-6.5, and from urine 79.4+/-6.9, 77.8+/-8.4, 83.3+/-6.6, 72.8+/-9.0, 76.3+/-7.7, 83.4+/-7.9, 81.6+/-7.9 and 81.8+/-6.8 for chlorpyrifos, chlorpyrifos-oxon, TCP, pyridostigmine bromide, N-methyl-3-hydroxypyridinium bromide, DEET, m-toluamide and m-toluic acid, respectively. The relationship between peak areas and concentration was linear over a range between 200 and 2000 ng/ml.

  16. A case report of QT prolongation with glycopyrronium bromide in a patient with chronic tamoxifen use.

    PubMed

    Chiu, Michael H; Al-Majed, Nawaf S; Stubbins, Ryan; Pollmann, Dylan; Sandhu, Roopinder K

    2016-06-14

    Glycopyrronium bromide has recently been approved as a once daily maintenance inhalation therapy for moderate to severe chronic obstructive pulmonary disease (COPD). Efficacy and safety trial data have found rare cases of significant QT prolongation. To our knowledge, we describe the first case report of QT prolongation >600 ms with initiation of glycopyrronium bromide in a real world setting. A 78-year-old female with moderate COPD recently started on glycopyrronium bromide, presented to Emergency Department (ED) with syncope. Her past medical history was significant for a left total mastectomy and she had been on Tamoxifen for 9 months. One day prior to her presentation, she had visited a naturopathic clinic for a vitamin infusion resulting in emesis. The following day she continued to feel dizzy and had a witnessed syncopal episode without any reported cardiac or neurological symptoms preceding the event or after regaining consciousness. In the emergency department, she reported dizziness and was found to be hypotensive. Her symptoms completely resolved with intravenous fluids. Lab work was normal however her electrocardiogram (ECG) demonstrated a QTc interval of 603 and 631 ms (Friderica and Bazett's respectively) with a normal QT interval on her baseline ECG prior to initiating Tamoxifen. She was admitted to the Cardiology service for further work-up of QT prolongation. Her syncope was felt to be due to orthostatic hypotension and the QT prolongation secondary to medications, which were both discontinued during her admission. After 2 days, her QT interval normalized consistent with the half-life of Glycopyrronium bromide (13-57 h) compared to Tamoxifen (8-14 days). Glycopyrronium bromide is guideline recommended as first line therapy for prevention of exacerbation in moderate to severe COPD however safety data had been limited to select populations. This case report highlights the need for future studies to identify high-risk populations at potential risk of life-threatening arrhythmias who may benefit from periodic ECG surveillance.

  17. Formation of vinyl halides via a ruthenium-catalyzed three-component coupling.

    PubMed

    Trost, Barry M; Pinkerton, Anthony B

    2002-06-26

    The ruthenium-catalyzed three-component coupling of an alkyne, an enone, and halide ion to form E- or Z-vinyl halides has been investigated. Through systematic optimization experiments, the conditions effecting the olefin selectivity were examined. In general, more polar solvents such as DMF favored the formation of the E-isomer, and less polar solvents such as acetone favored formation of the Z-isomer. The optimized conditions for the formation of E-vinyl chlorides were found to be the use of cyclopentadienyl ruthenium (II) cyclooctadiene chloride, stannic chloride pentahydrate as a cocatalyst, and for a chloride source, either ammonium chloride in DMF/water mixtures or tetramethylammonium chloride in DMF. A range of several other ruthenium (II) catalysts was also shown to be effective. A wide variety of vinyl chlorides could be formed under these conditions. Substrates with tethered alcohols or ketones either five or six carbons from the alkyne portion gave instead diketone or cyclohexenone products. For formation of vinyl bromides, a catalyst system involving the use of cyclopentadienylruthenium (II) tris(acetonitrile) hexafluorophosphate with stannic bromide as a cocatalyst was found to be most effective. The use of ammonium bromide in DMF/acetone mixtures was optimal for the synthesis of E-vinyl bromides, and the use of lithium bromide in acetone was optimal for formation of the corresponding Z-isomer. Under either set of conditions, a wide range of vinyl bromides could be formed. When alkynes with propargylic substituents are used, enhanced selectivity for formation of the Z-isomer is observed. When aryl acetylenes are used as the coupling partners, complete selectivity for the Z-isomer is obtained. A mechanism involving a cis or trans halometalation is invoked to explain formation of the observed products. The vinyl halides have been shown to be precursors to alpha-hydroxy ketones and cyclopentenones, and as coupling partners in Suzuki-type reactions.

  18. Impact of bromide on halogen incorporation into organic moieties in chlorinated drinking water treatment and distribution systems.

    PubMed

    Tan, J; Allard, S; Gruchlik, Y; McDonald, S; Joll, C A; Heitz, A

    2016-01-15

    The impact of elevated bromide concentrations (399 to 750 μg/L) on the formation of halogenated disinfection by-products (DBPs), namely trihalomethanes, haloacetic acids, haloacetonitriles, and adsorbable organic halogen (AOX), in two drinking water systems was investigated. Bromine was the main halogen incorporated into all of the DBP classes and into organic carbon, even though chlorine was present in large excess to maintain a disinfectant residual. Due to the higher reactivity of bromine compared to chlorine, brominated DBPs were rapidly formed, followed by a slower increase in chlorinated DBPs. Higher bromine substitution and incorporation factors for individual DBP classes were observed for the chlorinated water from the groundwater source (lower concentration of dissolved organic carbon (DOC)), which contained a higher concentration of bromide, than for the surface water source (higher DOC). The molar distribution of adsorbable organic bromine to chlorine (AOBr/AOCl) for AOX in the groundwater distribution system was 1.5:1 and almost 1:1 for the surface water system. The measured (regulated) DBPs only accounted for 16 to 33% of the total organic halogen, demonstrating that AOX measurements are essential to provide a full understanding of the formation of halogenated DBPs in drinking waters. In addition, the study demonstrated that a significant proportion (up to 94%) of the bromide in source waters can be converted AOBr. An evaluation of AOBr and AOCl through a second groundwater treatment plant that uses conventional treatment processes for DOC removal produced 70% of AOX as AOBr, with 69% of the initial source water bromide converted to AOBr. Exposure to organobromine compounds is suspected to result in greater adverse health consequences than their chlorinated analogues. Therefore, this study highlights the need for improved methods to selectively reduce the bromide content in source waters. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Cytotoxicity evaluation of five different dual-cured resin cements used for fiber posts cementation

    PubMed Central

    Dioguardi, M; Perrone, D; Troiano, G; Laino, L; Ardito, F; Lauritano, F; Cicciù, M; Lo Muzio, L

    2015-01-01

    Custom-cast posts and cores are usually used to treat endodontically treated teeth. However, several researches have underlined how these devices may be a much higher elastic modulus than the supporting dentine and the difference in the modulus could lead to stress concentrating in the cement lute, leading to failure. The role of the cement seems to play a fundamental role in order to transfer the strength during the chewing phases. Aim of this research is to record the rate of cytotoxicity of five different dual-cured resin cements used for fiber posts cementation. We tested the cytotoxicity of this five materials on MG63 osteoblast-like cells through two different methods: MTT ([3-4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide succinate) assay which tests for mitochondrial enzyme activity6 and xCELLigence® system. PMID:26309592

  20. Efficient perovskite light-emitting diodes featuring nanometre-sized crystallites

    NASA Astrophysics Data System (ADS)

    Xiao, Zhengguo; Kerner, Ross A.; Zhao, Lianfeng; Tran, Nhu L.; Lee, Kyung Min; Koh, Tae-Wook; Scholes, Gregory D.; Rand, Barry P.

    2017-01-01

    Organic-inorganic hybrid perovskite materials are emerging as highly attractive semiconductors for use in optoelectronics. In addition to their use in photovoltaics, perovskites are promising for realizing light-emitting diodes (LEDs) due to their high colour purity, low non-radiative recombination rates and tunable bandgap. Here, we report highly efficient perovskite LEDs enabled through the formation of self-assembled, nanometre-sized crystallites. Large-group ammonium halides added to the perovskite precursor solution act as a surfactant that dramatically constrains the growth of 3D perovskite grains during film forming, producing crystallites with dimensions as small as 10 nm and film roughness of less than 1 nm. Coating these nanometre-sized perovskite grains with longer-chain organic cations yields highly efficient emitters, resulting in LEDs that operate with external quantum efficiencies of 10.4% for the methylammonium lead iodide system and 9.3% for the methylammonium lead bromide system, with significantly improved shelf and operational stability.

  1. Shift Happens. How Halide Ion Defects Influence Photoinduced Segregation in Mixed Halide Perovskites

    DOE PAGES

    Yoon, Seog Joon; Kuno, Masaru; Kamat, Prashant V.

    2017-06-01

    Minimizing photoinduced segregation in mixed halide lead perovskites is important for achieving stable photovoltaic performance. The shift in the absorption and the rate of formation of iodide- and bromide-rich regions following visible excitation of mixed halide lead perovskites is found to strongly depend on the halide ion concentration. Slower formation and recovery rates observed in halide-deficient films indicate the involvement of defect sites in influencing halide phase segregation. At higher halide concentrations (in stoichiometric excess), segregation effects become less prominent, as evidenced by faster recovery kinetics. These results suggest that light-induced compositional segregation can be minimized in mixed halide perovskitemore » films by using excess halide ions. In conclusion, the findings from this study further reflect the importance of halide ion post-treatment of perovskite films to improve their solar cell performance.« less

  2. Removal of bromide and iodide anions from drinking water by silver-activated carbon aerogels.

    PubMed

    Sánchez-Polo, M; Rivera-Utrilla, J; Salhi, E; von Gunten, U

    2006-08-01

    The aim of this study is to analyze the use of Ag-doped activated carbon aerogels for bromide and iodide removal from drinking water and to study how the activation of Ag-doped aerogels affects their behavior. It has been observed that the carbonization treatment and activation process of Ag-doped aerogels increased the surface area value ( [Formula: see text] ), whereas the volume of meso-(V(2)) and macropores (V(3)) decreased slightly. Chemical characterization of the materials revealed that carbonization and especially activation process considerably increased the surface basicity of the sample. Original sample (A) presented acidic surface properties (pH(PZC)=4.5) with 21% surface oxygen, whereas the sample that underwent activation showed mainly basic surface chemical properties (pH(PZC)=9.5) with only 6% of surface oxygen. Carbonization and especially, activation process considerable increased the adsorption capacity of bromide and iodide ions. This would mainly be produced by (i) an increase in the microporosity of the sample, which increases Ag-adsorption sites available to halide anions, and (ii) a rise of the basicity of the sample, which produces an increase in attractive electrostatic interactions between the aerogel surface, positively charged at the working pH (pH(solution)

  3. 76 FR 7200 - Methyl Bromide; Notice of Receipt of Requests To Voluntarily Amend Registrations To Terminate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-09

    ... Receipt of Requests To Voluntarily Amend Registrations To Terminate Certain Soil Uses AGENCY... terminate or delete one or more soil uses. The requests would delete all methyl bromide soil uses that do... application'' with the exception of the following uses: (1) Soils to be planted with caneberries (use allowed...

  4. Assessment of the Mutagenic Potential of Carbon Disulfide, Carbon Tetrachloride, Dichloromethane, Ethylene Dichloride, and Methyl Bromide: A Comparative Analysis in Relation to Ethylene Dibromide

    EPA Science Inventory

    The document provides an evaluation of the mutagenic potential of five alternative fumigants to ethylene dibromide(EDB). These include carbon disulfide(CS2), carbon tetrachloride(CCl4), dichloromethane(DCM), ethylene dichloride(EDC), and methyl bromide (MB). Of the five proposed ...

  5. 75 FR 5582 - Methyl Bromide; Amendments to Terminate Uses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... Table 2 to amend to terminate post-harvest methyl bromide uses in or on alfalfa hay and cottonseed for... registered for use on alfalfa hay and cotton seed in the United States. In the September 30, 2009 notice, EPA... distribution by the registrant of existing stocks labeled for post-harvest alfalfa hay and post-harvest...

  6. 40 CFR 721.10115 - 1-Hexadecanaminium, N,N-dibutyl-N-(2-hydroxyethyl)-, bromide (1:1).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 1-Hexadecanaminium, N,N-dibutyl-N-(2... New Uses for Specific Chemical Substances § 721.10115 1-Hexadecanaminium, N,N-dibutyl-N-(2... chemical substance identified as 1-hexadecanaminium, N,N-dibutyl-N-(2-hydroxyethyl)-, bromide (1:1) (PMN P...

  7. 40 CFR 721.10115 - 1-Hexadecanaminium, N,N-dibutyl-N-(2-hydroxyethyl)-, bromide (1:1).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 1-Hexadecanaminium, N,N-dibutyl-N-(2... New Uses for Specific Chemical Substances § 721.10115 1-Hexadecanaminium, N,N-dibutyl-N-(2... chemical substance identified as 1-hexadecanaminium, N,N-dibutyl-N-(2-hydroxyethyl)-, bromide (1:1) (PMN P...

  8. Neuropsychological Functioning in Gulf War Veterans Exposed to Pesticides and Pyridostigmine Bromide

    DTIC Science & Technology

    2008-02-01

    processing speed and mood and sequelae from overt poisoning from organophosphate pesticides can result in lasting deficits in the domains of visuomotor...R. G., O’Malley, M., Chrislip, D., & Russo, J. (1994). Chronic neurological sequelae to organophosphate pesticide poisoning . American...War Veterans Exposed to Pesticides and Pyridostigmine Bromide PRINCIPAL INVESTIGATOR: Maxine Krengel, Ph.D

  9. Introducing the New Class of N-Phosphoryl Ynamides via Cu(I)-Catalyzed Amidations of Alkynyl Bromides

    PubMed Central

    Walton, Mary C.; North, Troy D.

    2011-01-01

    We describe here the first synthesis of N-phosphoryl ynamides featuring C- and P-chirality via copper(I)-catalyzed amidative cross-couplings between phosphoramidates and phosphordiamidates with alkynyl bromides. Also featured is a tandem aza-Claisen–hetero-[2+2] cycloaddition for the synthesis of N-phosphoryl azetidin-2-imines. PMID:21848304

  10. Comparison of percent hatch and fungal infestation in channel catfish eggs after copper sulfate, diquat bromide, formalin, and hydrogen peroxide treatment

    USDA-ARS?s Scientific Manuscript database

    Reduced survival is often a result of fungal (Saprolegnia spp.) infestation of fish eggs. However, timely chemical treatments often limit these infestations and increase survival. The effect of copper sulfate pentahydrate (CSP - 10 mg/L), diquat bromide (25 mg/L diquat cation), formalin (433 mg/L)...

  11. A clean start to productive orchards and vineyards: recent research on methyl bromide alternatives for perennial crop nurseries

    USDA-ARS?s Scientific Manuscript database

    Methyl bromide (MB) is an important pest management tool in open field perennial crop nurseries in California for control of many soil borne pests including plant parasitic nematodes, pathogens, and weeds. Because MB is being phased out under the provisions of the Montreal Protocol, alternatives are...

  12. Effects of Fumigant Alternatives to Methyl Bromide on Pest Control in Open Field Nursery Production of Perennial Fruit and Nut Plants

    USDA-ARS?s Scientific Manuscript database

    Producers of deciduous fruit and nut trees and vines rely on preplant fumigation to meet regulatory requirements designed to ensure nematode free planting stock. In the past, preplant treatments with methyl bromide or high rates of 1,3-dichloropropene were the preferred treatments. However, the ph...

  13. Using a Combination of Experimental and Mathematical Method to Explore Critical Micelle Concentration of a Cationic Surfactant

    ERIC Educational Resources Information Center

    Goronja, Jelena; Pejic´, Natas?a; Lez?aic´, Aleksandra Janos?evic´; Stanisavljev, Dragomir; Malenovic, Andelija

    2016-01-01

    An undergraduate electrical conductivity measurement experiment in a physical chemistry lab and basic fitting procedures are presented that allow a characterization of micellar system of hexadecyltrimethylammonium bromide (cetyltrimethylammonium bromide, CTAB) in binary mixture of water and acetonitrile (ACN) as a cosolvent (10%, v/v) at 30.0 °C.…

  14. 75 FR 57864 - Importation of Wooden Handicrafts from China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-23

    ... handicrafts are under 6 inches in diameter and treated with methyl bromide, they must be treated with heat... requirement that would have required that, unless the wooden handicraft is 6 inches or less and treated with methyl bromide, it must be treated with heat treatment in accordance with Sec. 319.40-7(c) or heat...

  15. Multicomponent Synthesis of a N-Protected Alpha-Amino Ester: Ethyl 2-((4-Methoxyphenyl)Amino)-3-Phenylpropanoate

    ERIC Educational Resources Information Center

    Le Gall, Erwan; Pignon, Antoine

    2012-01-01

    This laboratory experiment describes the preparation of a N-protected phenylalanine ethyl ester by a zinc-mediated Mannich-like multicomponent reaction between benzyl bromide, "p"-anisidine, and ethyl glyoxylate. The one-step reaction involves the in situ metallation of benzyl bromide into a benzylzinc reagent and its addition onto imine (Barbier…

  16. [Preparation and quality control of pyridostigmine bromide orally disintegrating tablet].

    PubMed

    Zhang, Li; Tan, Qun-you; Cheng, Xun-guan; Wang, Hong; Hu, Ni-ni; Zhang, Jing-qing

    2012-05-01

    To prepare orally disintegrating tablets containing pyridostigmine bromide and optimize formulations. Solid dispersion was prepared using solvent evaporation-deposition method. The formulation was optimized by central composite design-response surface methodology (RSM plus CCD) with disintegration time as a reference parameter. The orally disintegrating tablets showed integrity and were smooth with desirable taste and feel in mouth. The disintegration time was less than 30 s. The cumulative drug dissolution was around 8.5% (around 2.5 mg which was less than bitterness threshold of pyridostigmine bromide of 3 mg) within 5 min in water while the cumulative drug dissolution was higher than 95% within 2 min in 0.1 N HCl. The orally disintegrating tablets are reasonable in formulation, feasible in technology and patient-friendly.

  17. Experimental study of refrigeration performance based on linear Fresnel solar thermal photovoltaic system

    NASA Astrophysics Data System (ADS)

    Song, Jinghui; Yuan, Hui; Xia, Yunfeng; Kan, Weimin; Deng, Xiaowen; Liu, Shi; Liang, Wanlong; Deng, Jianhua

    2018-03-01

    This paper introduces the working principle and system constitution of the linear Fresnel solar lithium bromide absorption refrigeration cycle, and elaborates several typical structures of absorption refrigeration cycle, including single-effect, two-stage cycle and double-effect lithium bromide absorption refrigeration cycle A 1.n effect absorption chiller system based on the best parameters was introduced and applied to a linear Fresnel solar absorption chiller system. Through the field refrigerator performance test, the results show: Based on this heat cycle design and processing 1.n lithium bromide absorption refrigeration power up to 35.2KW, It can meet the theoretical expectations and has good flexibility and reliability, provides guidance for the use of solar thermal energy.

  18. Synthesis and characterization of new N-heterocyclic carbene ligands: 1,3-Bis(acetamide)imidazol-3-ium bromide and 3-(acetamide)-1-(3-aminopropyl)-1H-imidazol-3-ium bromide

    NASA Astrophysics Data System (ADS)

    Turkyilmaz, Murat; Uluçam, Gühergül; Aktaş, Şaban; Okan, S. Erol

    2017-05-01

    Two new pincer type N-heterocyclic carbene ligands were synthesized. The compounds were characterized by FTIR, NMR (1H, 13C) GC-MS and elemental analyses. They were also both modelled by DFT calculations as the crystal structure of 1,3-bis(acetamide)imidazol-3-ium bromide was determined by XRD which is an orthorhombic system with space group P21212. The structural analyses in gas phase were realized by comparing the experimental NMR and IR spectra with those of the theoretical calculations. In vitro biological activities of the molecules were determined and found that one of them exhibits significant cytotoxic activity.

  19. [The participation of the transport-barrier functions of the plasma membrane in the development of fluoroquinolone (ciprofloxacin) resistance in Acholeplasma laidlawii].

    PubMed

    Abramycheva, N Iu; Govorun, V M

    2000-01-01

    The role of transport activity of Acholeplasma laidlawii plasmatic membrane in the development of resistance to ciprofloxacin was investigated. It was shown that ethidium bromide used as fluoroquinolone analogue in plasmatic membrane efflux pump was accumulated in ciprofloxacin-resistant cells in much less amount. It was estimated that ethidium bromide efflux depended on temperature, glucose and transmembrane electro-chemical proton potential. Inhibitors of efflux systems--reserpine and verapamil enhanced the ethidium bromide accumulation much more intensively in ciprofloxacin resistant cells. The results of investigation allowed to consider the existence of active efflux system for toxic agents in acholeplasma; in the case of ciprofloxacin-resistant strain these systems are inducible.

  20. Demonstration of alcohol as an aviation fuel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1996-07-01

    A recently funded Southeastern Regional Biomass Energy Program (SERBEP) project with Baylor University will demonstrate the effectiveness of ethanols as an aviation fuel while providing several environmental and economic benefits. Part of this concern is caused by the petroleum industry. The basis for the petroleum industry to find an alternative aviation fuel will be dictated mainly by economic considerations. Three other facts compound the problem. First is the disposal of oil used in engines burning leaded fuel. This oil will contain too much lead to be burned in incinerators and will have to be treated as a toxic waste withmore » relatively high disposal fees. Second, as a result of a greater demand for alkalites to be used in the automotive reformulated fuel, the costs of these components are likely to increase. Third, the Montreal Protocol will ban in 1998 the use of Ethyl-Di-Bromide, a lead scavenger used in leaded aviation fuel. Without a lead scavenger, leaded fuels cannot be used. The search for alternatives to leaded aviation fuels has been underway by different organizations for some time. As part of the search for alternatives, the Renewable Aviation Fuels Development Center (RAFDC) at Baylor University in Waco, Texas, has received a grant from the Federal Aviation Administration (FAA) to improve the efficiencies of ethanol powered aircraft engines and to test other non-petroleum alternatives to aviation fuel.« less

  1. Determination of depleted uranium, pyridostigmine bromide and its metabolite in plasma and urine following combined administration in rats.

    PubMed

    Abu-Qare, A W; Abou-Donia, M B

    2001-09-01

    A simple and reliable method was developed for the quantification of depleted uranium, the anti nerve agent drug pyridostigmine bromide (PB;3-dimethylaminocarbonyloxy-N-methyl pyridinium bromide) and its metabolite N-methyl-3-hydroxypyridinium bromide in rat plasma and urine. The method involved using solid phase extraction and spectrophotometric determination of uranium, and high performance liquid chromatography (HPLC) with reversed phase C(18) column, and UV detection at 280 nm for PB and its metabolite. Uranium was derivatized using dibenzoylmethane (DBM) then the absorbance was measured at 405 nm. PB and its metabolite were separated using a gradient of 1--40% acetonitrile in 0.1% triflouroacetic acid water solution (pH 3.2) at a flow rate of 0.8 ml/min in a period of 14 min. Limits of detection were 2 ng/ml for uranium and 50 ng/ml for PB and its metabolite. Limits of quantitation were between 10 and 100 ng/ml for uranium and the other two analytes, respectively. Average percentage recovery of five spiked plasma samples were 83.7+/-8.6, 76.8+/-6.7, 79.1+/-7.1, and from urine 82.7+/-8.6, 79.3+/-9.5 and 78.0+/-6.2, for depleted uranium, PB and N-methyl-3-hydroxypyridinium bromide, respectively. The relationship between peak areas and concentration was linear for standards between 100 and 1000 ng/ml for all three analytes. This method was applied to analyze the above chemicals and metabolites following combined administration in rats.

  2. Hydrology and Water Quality near Bromide Pavilion in Chickasaw National Recreation Area, Murray County, Oklahoma, 2000

    USGS Publications Warehouse

    Andrews, William J.; Burrough, Steven P.

    2002-01-01

    The Bromide Pavilion in Chickasaw National Recreation Area drew many thousands of people annually to drink the mineral-rich waters piped from nearby Bromide and Medicine Springs. Periodic detection of fecal coliform bacteria in water piped to the pavilion from the springs, low yields of the springs, or flooding by adjacent Rock Creek prompted National Park Service officials to discontinue piping of the springs to the pavilion in the 1970s. Park officials would like to resume piping mineralized spring water to the pavilion to restore it as a visitor attraction, but they are concerned about the ability of the springs to provide sufficient quantities of potable water. Pumping and sampling of Bromide and Medicine Springs and Rock Creek six times during 2000 indicate that these springs may not provide sufficient water for Bromide Pavilion to supply large numbers of visitors. A potential problem with piping water from Medicine Spring is the presence of an undercut, overhanging cliff composed of conglomerate, which may collapse. Evidence of intermittent inundation of the springs by Rock Creek and seepage of surface water into the spring vaults from the adjoining creek pose a threat of contamination of the springs. Escherichia coli, fecal coliform, and fecal streptococcal bacteria were detected in some samples from the springs, indicating possible fecal contamination. Cysts of Giardia lamblia and oocysts of Cryptosporidium parvum protozoa were not detected in the creek or the springs. Total culturable enteric viruses were detected in only one water sample taken from Rock Creek.

  3. Large-scale, on-site confirmatory, and varietal testing of a methyl bromide quarantine treatment to control codling moth (Lepidoptera: Tortricidae) in nectarines exported to Japan.

    PubMed

    Yokoyama, V Y; Miller, G T; Hartsell, P L; Leesch, J G

    2000-06-01

    In total, 30,491 codling moth, Cydia pomonella (L.), 1-d-old eggs on May Grand nectarines in two large-scale tests, and 17,410 eggs on Royal Giant nectarines in four on-site confirmatory tests were controlled with 100% mortality after fumigation with a methyl bromide quarantine treatment (48 g3 for 2 h at > or = 21 degrees C and 50% volume chamber load) on fruit in shipping containers for export to Japan. Ranges (mean +/- SEM) were for percentage sorption 34.7 +/- 6.2 to 46.5 +/- 2.5, and for concentration multiplied by time products 54.3 +/- 0.9 to 74.5 +/- 0.6 g.h/m3 in all tests. In large-scale tests with May Grand nectarines, inorganic bromide residues 48 h after fumigation ranged from 6.8 +/- 0.7 to 6.9 +/- 0.5 ppm, which were below the U.S. Environmental Protection Agency tolerance of 20 ppm; and, organic bromide residues were < 0.01 ppm after 1 d and < 0.001 ppm after 3 d in storage at 0-1 degree C. After completion of larger-scale and on-site confirmatory test requirements, fumigation of 10 nectarine cultivars in shipping containers for export to Japan was approved in 1995. Comparison of LD50s developed for methyl bromide on 1-d-old codling moth eggs on May Grand and Summer Grand nectarines in 1997 versus those developed for nine cultivars in the previous 11 yr showed no significant differences in codling moth response among the cultivars.

  4. Modeling Source Water Threshold Exceedances with Extreme Value Theory

    NASA Astrophysics Data System (ADS)

    Rajagopalan, B.; Samson, C.; Summers, R. S.

    2016-12-01

    Variability in surface water quality, influenced by seasonal and long-term climate changes, can impact drinking water quality and treatment. In particular, temperature and precipitation can impact surface water quality directly or through their influence on streamflow and dilution capacity. Furthermore, they also impact land surface factors, such as soil moisture and vegetation, which can in turn affect surface water quality, in particular, levels of organic matter in surface waters which are of concern. All of these will be exacerbated by anthropogenic climate change. While some source water quality parameters, particularly Total Organic Carbon (TOC) and bromide concentrations, are not directly regulated for drinking water, these parameters are precursors to the formation of disinfection byproducts (DBPs), which are regulated in drinking water distribution systems. These DBPs form when a disinfectant, added to the water to protect public health against microbial pathogens, most commonly chlorine, reacts with dissolved organic matter (DOM), measured as TOC or dissolved organic carbon (DOC), and inorganic precursor materials, such as bromide. Therefore, understanding and modeling the extremes of TOC and Bromide concentrations is of critical interest for drinking water utilities. In this study we develop nonstationary extreme value analysis models for threshold exceedances of source water quality parameters, specifically TOC and bromide concentrations. In this, the threshold exceedances are modeled as Generalized Pareto Distribution (GPD) whose parameters vary as a function of climate and land surface variables - thus, enabling to capture the temporal nonstationarity. We apply these to model threshold exceedance of source water TOC and bromide concentrations at two locations with different climate and find very good performance.

  5. Banning of methyl bromide for seed treatment: could Ditylenchus dipsaci again become a major threat to alfalfa production in Europe?

    PubMed

    Mouttet, Raphaëlle; Escobar-Gutiérrez, Abraham; Esquibet, Magali; Gentzbittel, Laurent; Mugniéry, Didier; Reignault, Philippe; Sarniguet, Corinne; Castagnone-Sereno, Philippe

    2014-07-01

    In Europe, the stem and bulb nematode Ditylenchus dipsaci has been listed as a quarantine pest by EPPO: without any control, it may cause complete failure of alfalfa crops. Movement of nematodes associated with seeds is considered to be the highest-risk pathway for the spread of this pest. Since the 2010 official withdrawal of methyl bromide in Europe, and in the absence of any alternative chemical, fumigation of contaminated seed batches is no longer possible, which makes the production of nematode-free alfalfa seeds difficult to achieve and leads to unmarketable seed batches. Thermotherapy is being considered as a realistic alternative strategy, but its efficiency still remains to be validated. The combination of the currently available methods (i.e. use of resistant cultivars, seed production according to a certification scheme, mechanical sieving, seed batch inspection) could significantly reduce the likelihood of seed contamination. However, it does not guarantee a total eradication of the nematode. Although it is already widely distributed all over Europe, reclassification of D. dipsaci as a regulated non-quarantine pest to reduce the possibility of further introductions and the rate of spread of this pest appears to be a risky strategy because of the lack of up-to-date documented data to evaluate damage thresholds and determine acceptable tolerance levels. © 2014 Society of Chemical Industry.

  6. Evaluation of the effect of tetraethylammonium bromide and chloride on the growth and development of terrestrial plants.

    PubMed

    Pawłowska, Barbara; Biczak, Robert

    2016-04-01

    Quaternary ammonium salts (QAS), which also include ionic liquids, constitute a vast group of chemical compounds that are increasingly common in the commercial use. This situation may lead to the contamination of the natural environment and may constitute a potential threat to all its elements, including terrestrial higher plants. This paper presents the effect of tetraethylammonium chloride [TEA][Cl] and tetraethylammonium bromide [TEA][Br] on the growth and development of spring barley and common radish. The applied QAS were characterized with phytotoxicity dependent on the concentration of compound and characteristics of the study plants. Spring barley turned out to be highly susceptible plant to the analyzed compounds, which was confirmed by % inhibition of length of plants, root length and fresh weight of plants and by calculated values for EC50, NOEC as well as LOEC. On the contrary, a common radish revealed the resistance to QAS used in the study; although, phytotoxic symptoms were still observed when high concentrations of dry weight of soil were applied (1000, 3000 and 5000 mg/kg). The applied QAS caused oxidative stress symptoms, mainly in spring barley seedlings, which were manifested by decreased assimilation of pigments content, increased hydrogen peroxide (H2O2) and malondialdehyde (MDA) content in plant cells and with a changed activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Study on simultaneous recycling of EAF dust and plastic waste containing TBBPA.

    PubMed

    Grabda, Mariusz; Oleszek, Sylwia; Shibata, Etsuro; Nakamura, Takashi

    2014-08-15

    In the present work we investigated the fates of zinc, lead, and iron present in electric arc furnace dust during thermal treatment of the dust with tetrabromobisphenol A (TBBPA) and tetrabromobisphenol A diglycidyl ether (TBBPADGE). Mixtures of these materials were compressed into pellets and heated in a laboratory-scale furnace at 550 °C for 80 min, under oxidizing and inert conditions. The solid, condensed, and gaseous-phase products were characterized using an array of analytical methods: scanning electron microscopy, X-ray diffraction, electron probe microscopy, inductively coupled plasma, ion chromatography, and gas chromatography. The results indicated that heating the mixtures under specific conditions enabled high separation of zinc and lead from iron-rich residues, by a bromination-evaporation process. In the case of TBBPADGE, a maximum of 85% of zinc and 81% of lead were effectively separated under the above conditions. The process is based on the reaction between the highly reactive HBr gas evolved during thermal degradation of the flame-retarded materials with zinc (ZnO and ZnFe2O4) and lead in the dust, followed by complete evaporation of the formed metallic bromides from the solid residue. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Development of an activated carbon-based electrode for the capture and rapid electrolytic reductive debromination of methyl bromide from post-harvest fumigations

    USDA-ARS?s Scientific Manuscript database

    Due to concerns surrounding its ozone depletion potential, there is a need for technologies to capture and destroy methyl bromide (CH3Br) emissions from post-harvest fumigations applied to control agricultural pests. Previously we described a system in which CH3Br fumes vented from fumigation chambe...

  9. Human Metabolism and Interactions of Deployment-Related Chemicals

    DTIC Science & Technology

    2003-08-01

    with individual test compounds (final concentration, 100 PM), agent pyridostigmine bromide to protect against possible nerve gas NADPH-generating system...an insect repellent (N,N-diethyl-m- toluamide) a nerve gas prophyllactic (pyridostigmine bromide) did not cause the inhibition of trans-permethrin...mechanism of organophosphorus anticholinesterase agents , namely; covalent modification of the active site of the esterases in question. Carbaryl, another

  10. Effect of Dazomet Rate and Incorporation Method on Pine Production in Southern Pine Nurseries

    Treesearch

    L. David Dwinell; Stephen W. Fraedrich

    1998-01-01

    Southern forest-tree nurseries are growing an average of 1.2 billion seedlings per year or 80 percent of America's total seedling production. To control weeds and soil-borne pathogens, 89 percent of those nurseries fumigate, largely with methyl bromide. Dazomet (Basamide) is a chemical alternative to methyl bromide-chloropicrin for soil fumigation. Although...

  11. Comments on alternatives to methyl bromide for quarantine purposes in forest nurseries

    Treesearch

    David B. South

    2008-01-01

    Viewpoints will vary in regards to the best alternative to methyl bromide (CH3Br) fumigation. In some cases, crop value will determine the best alternative. As the value of the crop increases, the rate (and cost) of the "best" treatment might increase as well. In addition, the recommendation will depend on if the individual has a "...

  12. Seeking alternatives to probit 9 when developing treatments for wood packaging materials under ISPM No. 15

    Treesearch

    R.A. Haack; A. Uzunovic; K. Hoover; J.A. Cook

    2011-01-01

    ISPM No. 15 presents guidelines for treating wood packaging material used in international trade. There are currently two approved phytosanitary treatments: heat treatment and methyl bromide fumigation. New treatments are under development, and are needed given that methyl bromide is being phased out. Probit 9 efficacy (100% mortality of at least 93 613 test organisms...

  13. Fire extinguishant materials

    NASA Technical Reports Server (NTRS)

    Altman, R. L.; Mayer, L. A.; Ling, A. C. (Inventor)

    1983-01-01

    Fire extinguishant composition comprising a mixture of a finely divided aluminum compound and alkali metal, stannous or plumbous halide is provided. Aluminum compound may be aluminum hydroxide, alumina or boehmite but preferably it is an alkali metal dawsonite. The metal halide may be an alkali metal, e.g. potassium iodide, bromide or chloride or stannous or plumbous iodide, bromide or chloride. Potassium iodide is preferred.

  14. The history and future of methyl bromide alternatives in the southern United States

    Treesearch

    Tom E. Starkey

    2012-01-01

    This article gives a brief history of the efforts of the Southern Forest Nursery Management Cooperative (SFNMC) in testing methyl bromide (MBr) alternatives for soil fumigation. In the southeastern United States, fumigation with MBr has been the most commonly used method for producing high quality, pest-free forest seedlings in an environment that is conducive for soil...

  15. 40 CFR 180.123a - Inorganic bromide residues in peanut hay and peanut hulls; statement of policy.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Inorganic bromide residues in peanut hay and peanut hulls; statement of policy. 180.123a Section 180.123a Protection of Environment... combines and leave the hay on the ground to be incorporated into the soil, some growers follow the practice...

  16. Eradicating European pine shoot moth on ornamental pines with methyl bromide.

    Treesearch

    V.M. Carolin; W.H. Klein; R.M. Thompson

    1962-01-01

    The recent introduction of the European pine shoot moth into this region poses a serious threat to natural pine stands. To combat this threat, quarantines were invoked and eradication programs undertaken. Destruction of infested trees has been used tentatively as an eradication technique. In the meantime, fumigation with methyl bromide was tested over the period of a...

  17. Metabolism of proposed nerve agent pretreatment, pyridostigmine bromide. Final report, December 1995-December 1996

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leo, K.U.

    A reverse phase High Pressure Liquid Chromatography (HPLC) method was developed to separate pyridostigmine bromide from four potential metabolites. Using male and female microsomes from both rat and human, our data suggest that pyridostigmine bromide is not metabolized by the human live microsomes or DNA expressed human CYP-450s via direct observation of no metabolites being formed for incubations up to 90 minutes. Indirect evidence that pyridostigmine metabolism is not via the major human hepatic CYP-450s involved in drug metabolism, 1A2, 2C9, 2E1, 2D6, and 3A4, was observed by failure to inhibit these isozymes while co-incubated with substrates specific for thosemore » isozymes at concentrations of 2-3 times Km. The following CYP-450 substrates were co-incubated with pyridostigmine: phenacetin, tolbutamide, chlorzoxazone, bufuralol, and testosterone. Using unlabelled and 14C-pyridostigmine, metabolite formation was not observed in both male and female rat and human subcellular fractions, specifically cytosol and S9, or under conditions favoring human FMO activity (pH 8.3). These findings indicate the metabolism of pyridostigmine bromide is unlikely to be under any component of sexual dimorphism.« less

  18. The Acetyl Bromide Method Is Faster, Simpler and Presents Best Recovery of Lignin in Different Herbaceous Tissues than Klason and Thioglycolic Acid Methods

    PubMed Central

    Moreira-Vilar, Flavia Carolina; Siqueira-Soares, Rita de Cássia; Finger-Teixeira, Aline; de Oliveira, Dyoni Matias; Ferro, Ana Paula; da Rocha, George Jackson; Ferrarese, Maria de Lourdes L.; dos Santos, Wanderley Dantas; Ferrarese-Filho, Osvaldo

    2014-01-01

    We compared the amount of lignin as determined by the three most traditional methods for lignin measurement in three tissues (sugarcane bagasse, soybean roots and soybean seed coat) contrasting for lignin amount and composition. Although all methods presented high reproducibility, major inconsistencies among them were found. The amount of lignin determined by thioglycolic acid method was severely lower than that provided by the other methods (up to 95%) in all tissues analyzed. Klason method was quite similar to acetyl bromide in tissues containing higher amounts of lignin, but presented lower recovery of lignin in the less lignified tissue. To investigate the causes of the inconsistencies observed, we determined the monomer composition of all plant materials, but found no correlation. We found that the low recovery of lignin presented by the thioglycolic acid method were due losses of lignin in the residues disposed throughout the procedures. The production of furfurals by acetyl bromide method does not explain the differences observed. The acetyl bromide method is the simplest and fastest among the methods evaluated presenting similar or best recovery of lignin in all the tissues assessed. PMID:25330077

  19. [Bromate reduction by granular activated carbon].

    PubMed

    Huang, Xin; Gao, Nai-yun; Lu, Pin-pin

    2007-10-01

    Batch experiments were conducted to evaluate the kinetics of reducing bromate to bromide by granular activated carbon. Solution conditions were studied in details, such as pH, ionic strength, temperature and initial bromate concentration. The results showed the removal capacity of GAC was positively relevant to surface basic functional groups. The whole process was inhibited by other anions in solution and the inhibition sequence was NO3(-) > SO4(2-) > Cl(-). Pseudo-second order rate equation and intraparticle diffusion model were applied to fit the process of bromate reduction and the process of bromide formation, respectively, with regression coefficients higher than 0.97 at most cases. Bromate removal was found to be favored under conditions with low pH value and low ionic strength. Both sorption rate of bromate and formation rate of bromide were decreased, and then increased along with the increase of temperature during 15-42 degree C. In this experiment, the maximum adsorption capacity of GAC is 769.23 micromol/g (98.4 mg/g), whereas the sorption process is slow and easily influenced. It is concluded that the sorption of bromate by the micropore portion of GAC was influenced by the release of bromide.

  20. Unsaturated flow and transport through a fault embedded in fractured welded tuff

    USGS Publications Warehouse

    Salve, Rohit; Liu, Hui‐Hai; Cook, Paul; Czarnomski, Atlantis; Hu, Qinhong; Hudson, David

    2004-01-01

    To evaluate the importance of matrix diffusion as a mechanism for retarding radionuclide transport in the vicinity of a fault located in unsaturated fractured rock, we carried out an in situ field experiment in the Exploratory Studies Facility at Yucca Mountain, Nevada. This experiment involved the release of ∼82,000 L of water over a period of 17 months directly into a near‐vertical fault under both constant positive head (at ∼0.04 m) and decreasing fluxes. A mix of conservative tracers (pentafluorobenzoic acid (PFBA) and bromide (applied in the form of lithium bromide)) was released along the fault over a period of 9 days, 7 months after the start of water release along the fault. As water was released into the fault, seepage rates were monitored in a large cavity excavated below the test bed. After the release of tracers, seepage water was continuously collected from three locations and analyzed for the injected tracers. Observations of bromide concentrations in seepage water during the early stages of the experiment and bromide and PFBA concentrations in the seepage water indicate the significant effects of matrix diffusion on transport through a fault embedded in fractured, welded rock.

  1. Toxic impact of bromide and iodide on drinking water disinfected with chlorine or chloramines.

    PubMed

    Yang, Yang; Komaki, Yukako; Kimura, Susana Y; Hu, Hong-Ying; Wagner, Elizabeth D; Mariñas, Benito J; Plewa, Michael J

    2014-10-21

    Disinfectants inactivate pathogens in source water; however, they also react with organic matter and bromide/iodide to form disinfection byproducts (DBPs). Although only a few DBP classes have been systematically analyzed for toxicity, iodinated and brominated DBPs tend to be the most toxic. The objectives of this research were (1) to determine if monochloramine (NH2Cl) disinfection generated drinking water with less toxicity than water disinfected with free chlorine (HOCl) and (2) to determine the impact of added bromide and iodide in conjunction with HOCl or NH2Cl disinfection on mammalian cell cytotoxicity and genomic DNA damage induction. Water disinfected with chlorine was less cytotoxic but more genotoxic than water disinfected with chloramine. For both disinfectants, the addition of Br(-) and I(-) increased cytotoxicity and genotoxicity with a greater response observed with NH2Cl disinfection. Both cytotoxicity and genotoxicity were highly correlated with TOBr and TOI. However, toxicity was weakly and inversely correlated with TOCl. Thus, the forcing agents for cytotoxicity and genotoxicity were the generation of brominated and iodinated DBPs rather than the formation of chlorinated DBPs. Disinfection practices need careful consideration especially when using source waters containing elevated bromide and iodide.

  2. Interaction of ozone and carbon dioxide with polycrystalline potassium bromide and its atmospheric implication

    NASA Astrophysics Data System (ADS)

    Levanov, Alexander V.; Isaikina, Oksana Ya.; Maksimov, Ivan B.; Lunin, Valerii V.

    2017-03-01

    It has been discovered for the first time that gaseous ozone in the presence of carbon dioxide and water vapor interacts with crystalline potassium bromide giving gaseous Br2 and solid salts KHCO3 and KBrO3. Molecular bromine and hydrocarbonate ion are the products of one and the same reaction described by the stoichiometric equation 2KBr(cr.) + O3(gas) + 2CO2(gas) + H2O(gas) → 2KHCO3(cr.) + Br2(gas) + O2(gas). The dependencies of Br2, KHCO3 and KBrO3 formation rates on the concentrations of O3 and CO2, humidity of initial gas mixture, and temperature have been investigated. A kinetic scheme has been proposed that explains the experimental regularities found in this work on the quantitative level. According to the scheme, the formation of molecular bromine and hydrocarbonate is due to the reaction between hypobromite BrO-, the primary product of bromide oxidation by ozone, with carbon dioxide and water; bromate results from consecutive oxidation of bromide ion by ozone Br- → +O3 , -O2 BrO- → +O3 , -O2 BrO2- → +O3, -O2 BrO3- .

  3. Granular Activated Carbon Treatment May Result in Higher Predicted Genotoxicity in the Presence of Bromide.

    PubMed

    Krasner, Stuart W; Lee, Tiffany Chih Fen; Westerhoff, Paul; Fischer, Natalia; Hanigan, David; Karanfil, Tanju; Beita-Sandí, Wilson; Taylor-Edmonds, Liz; Andrews, Robert C

    2016-09-06

    Certain unregulated disinfection byproducts (DBPs) are more of a health concern than regulated DBPs. Brominated species are typically more cytotoxic and genotoxic than their chlorinated analogs. The impact of granular activated carbon (GAC) on controlling the formation of regulated and selected unregulated DBPs following chlorine disinfection was evaluated. The predicted cyto- and genotoxicity of DBPs was calculated using published potencies based on the comet assay for Chinese hamster ovary cells (assesses the level of DNA strand breaks). Additionally, genotoxicity was measured using the SOS-Chromotest (detects DNA-damaging agents). The class sum concentrations of trihalomethanes, haloacetic acids, and unregulated DBPs, and the SOS genotoxicity followed the breakthrough of dissolved organic carbon (DOC), however the formation of brominated species did not. The bromide/DOC ratio was higher than the influent through much of the breakthrough curve (GAC does not remove bromide), which resulted in elevated brominated DBP concentrations in the effluent. Based on the potency of the haloacetonitriles and halonitromethanes, these nitrogen-containing DBPs were the driving agents of the predicted genotoxicity. GAC treatment of drinking or reclaimed waters with appreciable levels of bromide and dissolved organic nitrogen may not control the formation of unregulated DBPs with higher genotoxicity potencies.

  4. Pyridostigmine bromide and the long-term subjective health status of a sample of female reserve component Gulf War veterans: a brief report.

    PubMed

    Schumm, W R; Reppert, E J; Jurich, A P; Bollman, S R; Castelo, C; Sanders, D; Webb, F J

    2001-02-01

    The role of pyridostigmine bromide (PB) pills in explaining the long-term subjective health status of a sample of over 100 female Reserve Component Gulf War veterans was examined through regression analysis. Results fell just short of significance (p < .06) for the prediction of subjective health approximately six years after the war and were clearly not significant for the prediction of subjective health at previous times. Results parallel Golomb's 1999 RAND report, which found suggestive but not conclusive evidence for the possible adverse effects of Gulf War veterans' consumption of pyridostigmine bromide pills. Our data suggest that use of more than 10 pills may have been especially risky with respect to long-term subjective health.

  5. Maintaining Flatness of a Large Aperture Potassium Bromide Beamsplitter Through Mounting and Vibration

    NASA Technical Reports Server (NTRS)

    Losch, Patricia; Lyons, James J., III; Morell, Armando; Heaney, Jim

    1998-01-01

    The Composite Infrared Spectrometer (CIRS) instrument on the Cassini Mission launched in October of 1997. The CIRS instrument contains a mid-infrared (MIR) and a far-infrared interferometer (FIR) and operates at 170 Kelvin. The MIR is a Michelson Fourier transform spectrometer utilizing a 76 mm (3 inch) diameter potassium bromide beamsplitter and compensator pair. The potassium bromide elements were tested to verify effects of cooldown and vibration prior to integration into the instrument. The instrument was then aligned at ambient temperatures, tested cryogenically and re-verified after vibration. 'Me stringent design optical figure requirements for the beamsplitter and compensator included fabrication errors, mounting stresses and vibration load effects. This paper describes the challenges encountered in mounting the elements to minimize distortion and to survive vibration.

  6. Maintaining Flatness of a Large Aperture Potassium Bromide Beamsplitter through Mounting and Vibration

    NASA Technical Reports Server (NTRS)

    Losch, Patricia; Lyons, James, III; Morell, Armando; Heaney, Jim

    1998-01-01

    The Composite Infrared Spectrometer (CIRS) instrument on the Cassini Mission launched in October of 1997. The CIRS instrument contains a mid-infrared and a far-infrared interferometer and operates at 170 Kelvin. The mid-infrared interferometer is a Michelson- type Fourier transform spectrometer utilizing a 3 inch diameter potassium bromide beamsplitter/compensator pair. The potassium bromide elements were tested to verify effects of cooldown and vibration prior to integration into the instrument. The instrument was then aligned at ambient temperatures, tested cryogenically and re-verified after vibration. The stringent design optical figure requirements for the beamsplitter and compensator included fabrication errors, mounting stresses and vibration load effects. This paper describes the challenges encountered in mounting the elements to minimize distortion and to survive vibration.

  7. Sorption of lead from aqueous solution by chemically modified carbon adsorbents.

    PubMed

    Nadeem, Muhammad; Mahmood, A; Shahid, S A; Shah, S S; Khalid, A M; McKay, G

    2006-12-01

    An indigenously prepared, steam activated and chemically modified carbon from husk and pods of Moringa oleifera (M. oleifera), an agricultural waste, was comparatively examined as an adsorbent for the removal of lead from aqueous solutions. Studies were conducted as a function of contact time, initial metal concentration, dose of adsorbent, agitation speed, particle size and pH. Maximum uptake capacities were found to be, 98.89, 96.58, 91.8, 88.63, 79.43% for cetyltrimethyl ammonium bromide (CTAB), phosphoric, sulfuric, hydrochloric acid treated and untreated carbon adsorbents, respectively. Bangham, pseudo-first- and second-order, intra-particle diffusion equations were implemented to express the sorption mechanism by utilized adsorbents. Adsorption rate of lead ions was found to be considerably faster for chemically modified adsorbents than unmodified. The results of adsorption were fitted to both the Langmuir and Freundlich models. Satisfactory agreement between the metal uptake capacities by the adsorbents at different time intervals was expressed by the correlation coefficient (R(2)). The Langmuir model represented the sorption process better than the Freundlich one, with R(2) values ranging from 0.994 to 0.998.

  8. Implications of a Multi-well Tracer Test in the Transport of Pathogens at a Riverbank Filtration Experiment Site.

    NASA Astrophysics Data System (ADS)

    Langford, R. P.; Pillai, S.; Schulze-Makuch, D.; Widmer, K.; Abdel-Fattah, A.; Lerhner, T.

    2003-12-01

    This study tracks the transport of bromide and microspheres mimicking pathogens in an arid environment. The study site uses the Rio Grande that experiences significant annual fluctuations in both water quantity and quality. The pumping well is 17 m from the stream bank and the water table was 2 m below the stream surface. The aquifer is medium and fine-grained sand comprising two flow units. Observation wells are screened over 1 or 1.5 m intervals. The average hydraulic conductivity was about 2 x 10-3 m/s based on a test analysis, however, the responses indicated that sediment heterogeneities affected the hydraulic behavior. A 427 hour tracer test using bromide and fluorescent microspheres provides initial results that are relevant to the transport of pathogens through the subsurface under riverbank filtration conditions. Bromide was injected into an observation well at the channel margin. Differently colored fluorescent microspheres (0.25nm, 1?m, 6?m and 10?m) were injected into the stream bottom and into two observation wells. Conclusions from the tracer test are: 1) Both bromide and microspheres continued to be observed throughout the 18 days of the experiment. 2) The bromide recovery in the pumping well and in the deeper observation wells showed early and late peaks with a long tails indicating that the geological medium at the field site behaves like a double-porosity medium allowing the tracer to move relatively quickly through the higher conductivity units while being significantly retarded in the low hydraulic conductivity units. 3) Some wells showed consistently higher concentrations of bromide. 4) The 1? micospheres were abundant in the observation wells and allowed tracing of flowpaths. These showed multiple peaks similar to the bromide results. This indicates highly preferential transport paths in the sediment. 5) Microspheres from the three injection sites had distinctly different transport paths and rates. 6) Both bromide and microspheres appeared in the stream soon after injection, moving apparently against an 2-m head difference. 7) The 6 ? and 10 ? microspheres were observed in low concentrations and were episodically detected in the stream and in two widely spaced observation wells. The significance of these results is that: 1) Inorganic microspheres may mimic the episodic occurrence of microorganisms in wells. 2) Even in this relatively homogeneous aquifer, preferential transport within the aquifer results in highly divergent transport paths and rates. Microspheres from one of the injection sites traveled essentially perpendicular to the expected transport direction. 3) Even small variations in the sand grain size can effectively compartmentalize the aquifer. The next steps of this project will include field studies to observe the migration and persistence of selected organisms (E.coli, enterococci, coliphages, cysts, oocysts and enteroviruses) in the pumping well and observation wells under different pumping rates. Continued combined chemical sampling along with the microbial sampling will document the whether changes in water chemistry alter the behavior of the organisms.

  9. The toxicity study of functionalized CNT from fermented tapioca on neuroblastoma cell

    NASA Astrophysics Data System (ADS)

    Nurulhuda, I.; Mazatulikhma, M. Z.; Alrokayan, S.; Khan, H.; Rusop, M.

    2018-05-01

    Carbon nanotubes known as one of the most interesting types of nanomaterials, especially use in application directly to cells. Somehow the use should take into consideration regarding the potential adverse impact on human health. Current study, the carbon nanotube was synthesized from fermented tapioca and functionalized with polyethylene glycol and directly test on the neuroblastoma cells in vitro. The toxicity effect on cells was assessed by 3(4, 5-dimethylthiazol-2-yl)-2, 5-tetrazolium bromide assays. It showed a dose-and time-dependent less toxic effect on functionalized carbon nanotube compared to non-functionalized. This leads us to the conclusion that functionalized carbon nanotube can be use for drug delivery in future.

  10. Two-Dimensional Perovskite Activation with an Organic Luminophore.

    PubMed

    Jemli, Khaoula; Audebert, Pierre; Galmiche, Laurent; Trippé-Allard, Gaelle; Garrot, Damien; Lauret, Jean-Sébastien; Deleporte, Emmanuelle

    2015-10-07

    A great advantage of the hybrid organic-inorganic perovskites is the chemical flexibility and the possibility of a molecular engineering of each part of the material (the inorganic part and the organic part respectively) in order to improve or add some functionalities. An adequately chosen organic luminophore has been introduced inside a lead bromide type organic-inorganic perovskite, while respecting the two-dimensional perovskite structure. A substantial increase of the brilliance of the perovskite is obtained. This activation of the perovskite luminescence by the adequate engineering of the organic part is an original approach, and is particularly interesting in the framework of the light-emitting devices such as organic light-emitting diodes (OLEDs) or lasers.

  11. Control of oleylamine to perovskite ratio in synthesis of MAPbBr3 nanoparticles

    NASA Astrophysics Data System (ADS)

    Huang, Jing; Wu, Yi-Hua; Zhu, Zhi-Gang; Shih, Wan Y.; Shih, Wei-Heng

    2018-06-01

    Methylammonium lead bromide (CH3NH3PbBr3) nanocrystals have great potentials for lighting and display applications. Previously we synthesized CH3NH3PbBr3 nanocrystals using oleylamine as capping molecule and found that by increasing the oleylamine to CH3NH3PbBr3 perovskite ratio (OPR), the photoluminescence wavelengths and morphology of CH3NH3PbBr3 nanocrystals could be varied from 530 nm (green) platelets to 460 nm (blue) particles. Here we modified the synthesis to direct injection of precursors into toluene and found that increasing OPR not only changes the wavelength and morphology of nanocrystals but also the size of the unit cells.

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

    NASA Astrophysics Data System (ADS)

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

    2017-04-01

    Oxidation of bromide by gas phase ozone (O3) in the absence of photochemistry is believed to be one of the important dark reactions to produce HOBr as the starting point of the multiphase cycling reaction mechanisms that release bromide out of sea water, sea spray or marine aerosols from aqueous solution that later drive O3 depleting chemistry in the troposphere [1]. The reaction of bromide with O3 occurs through an acid catalyzed mechanism involving a BrOOO- complex as an intermediate [2]. Slow oxidation of bromide by O3 in the bulk aqueous phase is of limited relevance; previous kinetic experiments have suspected the reaction to be enhanced at the surface of aqueous solutions. Thus, identifying BrOOO- at the interface would be a major step to understanding the multiphase oxidation of bromide with O3. Here, we provide a direct experimental evidence for the formation of a BrOOO- reaction intermediate at the surface by investigating the reaction of aqueous solutions NaBr with gas phase O3 after millisecond time scale exposure using the surface sensitive in situ liquid jet X-ray photoelectron spectroscopy (XPS) at the Swiss Light Source (SLS). We acquired Br 3d core level spectra of 0.125 M NaBr solution in presence and absence of ozone in the gas phase. We found a new feature with a peak position shifted towards higher binding energy (by ˜0.7 eV) compared to Br-, which was clearly different from the Br 3d core levels spectra of hypobromite and bromate measured with reference solutions. Our results suggest the appearance of the formation of the BrOOO- reaction intermediate as a new component, in agreement with theoretical calculations of the Br- ozonolysis mechanism [3]. Additionally, by varying the photoelectron kinetic energy and thus probe depth via variation of the probing photon energy, the new feature appears to be present near the liquid/vapor interface. Besides, kinetic experiments for the reaction of O3 with bromide are ongoing to investigate the dependence on the temperature, ozone concentration, which may give further information such as the relative oxidation rate at the liquid/vapor interface versus that in the bulk phase. [1] S. Wang, et al., Proceedings of the National Academy of Sciences, 2015, 112, 9281-9286. [2] Q. Liu, et al., Inorganic Chemistry, 2001, 40, 4436-4442. [3] I. Gladich, et al., The Journal of Physical Chemistry A, 2015, 119, 4482-4488.

  13. Activated carbons from end-products of tree nut and tree fruit production as sorbents for removing methyl bromide in ventilation effluent from postharvest chamber fumigation

    USDA-ARS?s Scientific Manuscript database

    End-products of tree nuts and tree fruits grown in California, USA were evaluated for the ability to remove methyl bromide from the ventilation effluent of postharvest chamber fumigations. Activated carbon sorbents from walnut and almond shells as well as peach and prune pits were prepared using dif...

  14. Formation of Worm-Like Micelles in Mixed N-Hexadecyl-N-Methylpyrrolidinium Bromide-Based Cationic Surfactant and Anionic Surfactant Systems

    PubMed Central

    Dai, Caili; Yan, Zhihu; You, Qing; Du, Mingyong; Zhao, Mingwei

    2014-01-01

    Through the descriptive and rheological characterization of worm-like micelles formed by N-hexadecyl-N-methylpyrrolidinium bromide and sodium laurate, the formation and properties of the worm-like micelles were affected by the concentrations of sodium laurate and temperature. Additionally, cryogenic transmission electron microscopy images further validated the formation of worm-like micelles. PMID:25019152

  15. Alkali Halide FLIR Lens Development

    DTIC Science & Technology

    1981-10-01

    in the atmosphere. The main emphasis in this 3 report has been development of protective coatings for potassium bromide lenses. The most favorable...placed onto the bottom electrode. Pieces of single-crystalline potassium chloride of approximately the same thickness as coated alkali halide samples...none of the samples appeared to be degraded by the high humidity associated with the exposure. 2. UNITS TESTED Four coated potassium bromide lenses

  16. Bromidotetra-kis-(2-isopropyl-1H-imidazole-κN)copper(II) bromide.

    PubMed

    Godlewska, Sylwia; Socha, Joanna; Baranowska, Katarzyna; Dołęga, Anna

    2011-10-01

    The Cu(II) atom in the title salt, [CuBr(C(6)H(10)N(2))(4)]Br, is coordinated in a square-pyramidal geometry by four imidazole N atoms and one bromide anion that is located at the apex of the pyramid. The cations and the anions form a two-dimensional network parallel to (001) through N-H⋯Br hydrogen bonds.

  17. Simultaneous determination of pyridostigmine bromide, N,N-diethyl-m-toluamide, permethrin, and their metabolites in rat plasma and urine by high-performance liquid chromatography.

    PubMed

    Abu-Qare, A W; Abou-Donia, M B

    2000-12-01

    A rapid and simple method was developed for the separation and quantification of the anti nerve agent drug pyridostignmine bromide (PB; 3-dimethylaminocarbonyloxy-N-methyl pyridinium bromide) its metabolite N-methyl-3-hydroxypyridinium bromide, the insect repellent DEET (N,N-diethyl-m-toluamide), its metabolites m-toluamide and m-toluic acid, the insecticide permethrin (3-(2,2-dichloro-ethenyl)-2,2-dimethylcyclopropanecarboxylic acid(3-phenoxyphenyl)methylester), and two of its metabolites m-phenoxybenzyl alcohol, and m-phenoxybenzoic acid in rat plasma and urine. The method is based on using C18 Sep-Pak cartridges for solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) with reversed-phase C18 column, and gradient UV detection ranging between 208 and 230 nm. The compounds were separated using gradient of 1 to 99% acetonitrile in water (pH 3.20) at a flow-rate ranging between 0.5 and 1.7 ml/min in a period of 17 min. The retention times ranged from 5.7 to 14.5 min. The limits of detection were ranged between 20 and 100 ng/ml, while limits of quantitation were 150-200 ng/ml. Average percentage recovery of five spiked plasma samples were 51.4+/-10.6, 71.1+/-11.0, 82.3+/-6.7, 60.4+/-11.8, 63.6+/-10.1, 69.3+/-8.5, 68.3+/-12.0, 82.6+/-8.1, and from urine 55.9+/-9.8, 60.3+/-7.4, 77.9+/-9.1, 61.7+/-13.5, 68.6+/-8.9, 62.0+/-9.5, 72.9+/-9.1, and 72.1+/-8.0, for pyridostigmine bromide, DEET, permethrin, N-methyl-3-hydroxypyridinium bromide, m-toluamide, m-toluic acid, m-phenoxybenzyl alcohol and m-phenoxybenzoic acid, respectively. The relationship between peak areas and concentration was linear over the range between 100 and 5000 ng/ml. This method was applied to analyze the above chemicals and metabolites following their administration in rats.

  18. Efficacy of supplemental anti-inflammatory therapy with fenspiride in chronic obstructive and nonobstructive bronchitis.

    PubMed

    Volkova, L I; Budkova, A A; Filonova, N N; Khristolyubova, E I; Kutuzova, E B; Koroleva, N V; Radzivil, T T; Aminova, Z R; Chuchalin, A G

    2005-01-01

    The objective of this randomised, nonblind study was to assess the efficacy of fenspiride as complementary anti-inflammatory therapy in combination with ipratropium bromide in patients with chronic bronchitis (CB). A comparison was made with ipratropium bromide alone, the generally accepted standard therapy for CB. The study population comprised 20 patients with chronic obstructive bronchitis (COB) and 60 patients without signs of obstruction. Fifty-one males (64%) and 29 females (36%) aged from 25 to 65 years were studied over a 6-month treatment period. Combined therapy with fenspiride (160 mg/day) and ipratropium bromide (160 mug/day) was prescribed to 39 patients (28 with CB and 11 with COB) for 6 months, and monotherapy with ipratropium bromide (160 microg/day) was prescribed for 41 patients (32 with CB and nine with COB). The combined therapy group had a reduced intensity of dyspnoea, improvements in sputum nature and quantity of exudation, and a reduced intensity of coughing. The monotherapy group showed reductions in sputum exudation and cough intensity. Improvements in lung respiratory function were observed in both groups, but were greater in the combined therapy group of patients. Reduced cytosis, percentage and absolute content of neutrophils, and absolute content of lymphocytes and eosinophils in induced sputum were observed with CB patients in the combined therapy group. A reduced content of lymphocytes and an increase in macrophages were observed with CB patients in the monotherapy group. A significant decline in tumour necrosis factor (TNF)-alpha content in sputum was observed with both therapeutic regimens, although a statistically significant decline in serum TNFalpha (10.85 ng/L to 5.58 ng/L; p = 0.03) and reduced interleukin-8 in sputum (311.94 ng/L to 122.02 ng/L; p = 0.027) were observed with patients given combined therapy. The study showed greater efficacy of long-term treatment with fenspiride and ipratropium bromide compared with ipratropium bromide alone in patients with CB. This combination regimen can be recommended for the reduction of inflammation and prevention of disease progression in patients with CB and may also be useful in patients with COB.

  19. Controlling First-Row Catalysts: Amination of Aryl and Heteroaryl Chlorides and Bromides with Primary Aliphatic Amines Catalyzed by a BINAP-Ligated Single-Component Ni(0) Complex

    PubMed Central

    2015-01-01

    First-row metal complexes often undergo undesirable one-electron redox processes during two-electron steps of catalytic cycles. We report the amination of aryl chlorides and bromides with primary aliphatic amines catalyzed by a well-defined, single-component nickel precursor (BINAP)Ni(η2-NC-Ph) (BINAP = 2,2′-bis(biphenylphosphino)-1,1′-binaphthalene) that minimizes the formation of Ni(I) species and (BINAP)2Ni. The scope of the reaction encompasses electronically varied aryl chlorides and nitrogen-containing heteroaryl chlorides, including pyridine, quinoline, and isoquinoline derivatives. Mechanistic studies support the catalytic cycle involving a Ni(0)/Ni(II) couple for this nickel-catalyzed amination and are inconsistent with a Ni(I) halide intermediate. Monitoring the reaction mixture by 31P NMR spectroscopy identified (BINAP)Ni(η2-NC-Ph) as the resting state of the catalyst in the amination of both aryl chlorides and bromides. Kinetic studies showed that the amination of aryl chlorides and bromides is first order in both catalyst and aryl halide and zero order in base and amine. The reaction of a representative aryl chloride is inverse first order in PhCN, but the reaction of a representative aryl bromide is zero order in PhCN. This difference in the order of the reaction in PhCN indicates that the aryl chloride reacts with (BINAP)Ni(0), formed by dissociation PhCN from (BINAP)Ni(η2-NC-Ph), but the aryl bromide directly reacts with (BINAP)Ni(η2-NC-Ph). The overall kinetic behavior is consistent with turnover-limiting oxidative addition of the aryl halide to Ni(0). Several pathways for catalyst decomposition were identified, such as the formation of the catalytically inactive bis(amine)-ligated arylnickel(II) chloride, (BINAP)2Ni(0), and the Ni(I) species [(BINAP)Ni(μ-Cl)]2. By using a well-defined nickel complex as catalyst, the formation of (BINAP)2Ni(0) is avoided and the formation of the Ni(I) species [(BINAP)Ni(μ-Cl)]2 is minimized. PMID:24397570

  20. Pyridostigmine treatment trial in neurogenic orthostatic hypotension.

    PubMed

    Singer, Wolfgang; Sandroni, Paola; Opfer-Gehrking, Tonette L; Suarez, Guillermo A; Klein, Caroline M; Hines, Stacy; O'Brien, Peter C; Slezak, Jeffrey; Low, Phillip A

    2006-04-01

    Midodrine hydrochloride is the only drug demonstrated in a placebo-controlled treatment trial to improve orthostatic hypotension (OH) but it significantly worsens supine hypertension. By enhancing ganglionic transmission, pyridostigmine bromide can potentially ameliorate OH without worsening supine hypertension. To evaluate the efficacy of a single 60-mg dose of pyridostigmine bromide, alone or in combination with a subthreshold (2.5 mg) or suprathreshold (5 mg) dose of midodrine hydrochloride, compared with placebo. We report a double-blind, randomized, 4-way cross-over study of pyridostigmine in the treatment of neurogenic OH. A total of 58 patients with neurogenic OH were enrolled. After 1 day of baseline measurements, patients were given 4 treatments (3 active treatments [60 mg of pyridostigmine bromide; 60 mg of pyridostigmine bromide and 2.5 mg of midodrine hydrochloride; 60 mg of pyridostigmine bromide and 5 mg of midodrine hydrochloride] and a placebo) in random order on successive days. Blood pressure (BP) and heart rate were measured, both supine and standing, immediately before treatment and hourly for 6 hours after the treatment was given. No significant differences were seen in the supine BP, either systolic (P = .36) or diastolic (P = .85). In contrast, the primary end point of the fall in standing diastolic BP was significantly reduced (P = .02) with treatment. Pairwise comparison showed significant reduction by pyridostigmine alone (BP fall of 27.6 mm Hg vs 34.0 mm Hg with placebo; P = .04) and pyridostigmine and 5 mg of midodrine hydrochloride (BP fall of 27.2 mm Hg vs 34.0 mm Hg with placebo; P = .002). Standing BP improvement significantly regressed with improvement in OH symptoms. Pyridostigmine significantly improves standing BP in patients with OH without worsening supine hypertension. The greatest effect is on diastolic BP, suggesting that the improvement is due to increased total peripheral resistance.

  1. High-performance liquid chromatographic determination of pyridostigmine bromide, nicotine, and their metabolites in rat plasma and urine.

    PubMed

    Abu-Qare, A W; Abou-Donia, M B

    2001-07-01

    This study reports on the development of a rapid and simple method for the determination of the antinerve agent drug pyridostigmine bromide (3-dimethylaminocarbonyloxy-N-methyl pyridinium bromide) (PB), its metabolite N-methyl-3-hydroxypyridinium bromide, nicotine (S-1-methyl-5-(3-pyridyl)-2-pyrrolidine), and its metabolites nornicotine (2-(3-pyridyl)pyrrolidine) and cotinine (S-1-methyl-5-(3-pyridyl)-2-pyrrolidone) in rat plasma and urine. The compounds are extracted and eluted by methanol and acetonitrile using C18 Sep-Pak cartridges and separated using high-performance liquid chromatography by a gradient of methanol, acetonitrile, and water (pH 3.2) at a flow rate of 0.8 mL/min in a period of 14 min. UV detection was at 260 nm for nicotine and its metabolites and at 280 nm for PB and its metabolite. The limits of detection ranged between 20 and 70 ng/mL, and the limits of quantitation were 50-100 ng/mL. The average percent recovery of five spiked plasma samples were 85.7 +/- 7.3%, 80.4 +/- 5.8%, 78.9 +/- 5.4%, 76.7 +/- 6.4%, and 79.7 +/- 5.7% and for urine were 85.9 +/- 5.9%, 75.5 +/- 6.9%, 82.6 +/- 7.9%, 73.6 +/- 5.9%, and 77.7 +/- 6.3% for nicotine, nornicotine, cotinine, PB, and N-methyl-3-hydroxypyridinium bromide, respectively. The calibration curves for standard solutions of the compounds of peak areas and concentration are linear for a range between 100 and 1,000 ng/mL. This method is applied in order to analyze the previously mentioned chemicals and metabolites following their oral administration in rats.

  2. Estimating groundwater recharge in Hebei Plain, China under varying land use practices using tritium and bromide tracers

    NASA Astrophysics Data System (ADS)

    Wang, Bingguo; Jin, Menggui; Nimmo, John R.; Yang, Lei; Wang, Wenfeng

    2008-07-01

    SummaryTritium and bromide were used as applied tracers to determine groundwater recharge in Hebei Plain, North China, to evaluate the impacts of different soil types, land use, irrigation, and crop cultivation practice on recharge. Additional objectives were to evaluate temporal variability of recharge and the effect on results of the particular tracer used. Thirty-nine profiles at representative locations were chosen for investigation. Average recharge rates and recharge coefficient determined by tritium and bromide tracing for different sites were 0.00-1.05 mm/d and 0.0-42.5%, respectively. The results showed relative recharge rates for the following paired influences (items within each pair are listed with the influence producing greater recharge first): flood-irrigated cropland and non-irrigated non-cultivation land, flood irrigation (0.42-0.58 mm/d) and sprinkling irrigation (0.17-0.23 mm/d), no stalk mulch (0.56-0.80 mm/d) and stalk mulch (0.44-0.60 mm/d), vegetable (e.g. Chinese cabbage and garlic, 0.70 mm/d) and wheat-maize (0.38 mm/d), peanut (0.51 mm/d) and peach (0.43 mm/d). The results also showed greater recharge for the first year of tracer travel than for the second. Because total precipitation and irrigation were greater in the first year than in the second, this may reflect temporal variability of recharge. The method may not be applicable where the water table is shallow (less than 3 m). A comparison of the near-ideal tritium tracer with the more common but less ideal bromide showed that bromide moved approximately 23% faster than tritiated water, perhaps because of anion exclusion.

  3. Replacing Conventional Carbon Nucleophiles with Electrophiles: Nickel-Catalyzed Reductive Alkylation of Aryl Bromides and Chlorides

    PubMed Central

    2012-01-01

    A general method is presented for the synthesis of alkylated arenes by the chemoselective combination of two electrophilic carbons. Under the optimized conditions, a variety of aryl and vinyl bromides are reductively coupled with alkyl bromides in high yields. Under similar conditions, activated aryl chlorides can also be coupled with bromoalkanes. The protocols are highly functional-group tolerant (−OH, −NHTs, −OAc, −OTs, −OTf, −COMe, −NHBoc, −NHCbz, −CN, −SO2Me), and the reactions are assembled on the benchtop with no special precautions to exclude air or moisture. The reaction displays different chemoselectivity than conventional cross-coupling reactions, such as the Suzuki–Miyaura, Stille, and Hiyama–Denmark reactions. Substrates bearing both an electrophilic and nucleophilic carbon result in selective coupling at the electrophilic carbon (R–X) and no reaction at the nucleophilic carbon (R–[M]) for organoboron (−Bpin), organotin (−SnMe3), and organosilicon (−SiMe2OH) containing organic halides (X–R–[M]). A Hammett study showed a linear correlation of σ and σ(−) parameters with the relative rate of reaction of substituted aryl bromides with bromoalkanes. The small ρ values for these correlations (1.2–1.7) indicate that oxidative addition of the bromoarene is not the turnover-frequency determining step. The rate of reaction has a positive dependence on the concentration of alkyl bromide and catalyst, no dependence upon the amount of zinc (reducing agent), and an inverse dependence upon aryl halide concentration. These results and studies with an organic reductant (TDAE) argue against the intermediacy of organozinc reagents. PMID:22463689

  4. Estimating groundwater recharge in Hebei Plain, China under varying land use practices using tritium and bromide tracers

    USGS Publications Warehouse

    Wang, B.; Jin, M.; Nimmo, J.R.; Yang, L.; Wang, W.

    2008-01-01

    Tritium and bromide were used as applied tracers to determine groundwater recharge in Hebei Plain, North China, to evaluate the impacts of different soil types, land use, irrigation, and crop cultivation practice on recharge. Additional objectives were to evaluate temporal variability of recharge and the effect on results of the particular tracer used. Thirty-nine profiles at representative locations were chosen for investigation. Average recharge rates and recharge coefficient determined by tritium and bromide tracing for different sites were 0.00-1.05 mm/d and 0.0-42.5%, respectively. The results showed relative recharge rates for the following paired influences (items within each pair are listed with the influence producing greater recharge first): flood-irrigated cropland and non-irrigated non-cultivation land, flood irrigation (0.42-0.58 mm/d) and sprinkling irrigation (0.17-0.23 mm/d), no stalk mulch (0.56-0.80 mm/d) and stalk mulch (0.44-0.60 mm/d), vegetable (e.g. Chinese cabbage and garlic, 0.70 mm/d) and wheat-maize (0.38 mm/d), peanut (0.51 mm/d) and peach (0.43 mm/d). The results also showed greater recharge for the first year of tracer travel than for the second. Because total precipitation and irrigation were greater in the first year than in the second, this may reflect temporal variability of recharge. The method may not be applicable where the water table is shallow (less than 3 m). A comparison of the near-ideal tritium tracer with the more common but less ideal bromide showed that bromide moved approximately 23% faster than tritiated water, perhaps because of anion exclusion. ?? 2008 Elsevier B.V.

  5. Ni-catalyzed reductive homocoupling of unactivated alkyl bromides at room temperature and its synthetic application.

    PubMed

    Peng, Yu; Luo, Long; Yan, Chang-Song; Zhang, Jian-Jian; Wang, Ya-Wen

    2013-11-01

    A room-temperature Ni-catalyzed reductive approach to homocoupling of unactivated primary, secondary, and tertiary alkyl bromides is described. The catalytic system can be easily generated from air-stable and cheap materials and demonstrates broad functional group tolerance, thus allowing facile access to useful dimeric triterpene and lignan-like molecules. Moreover, the dimerization of tertiary bromide 6 efficiently establishes sterically hindered vicinal quaternary carbons (C3a and C3a'), which is a key linkage of intriguing bispyrrolo[2,3-b]indoline alkaloids, thereby enabling us to complete the total syntheses of racemic chimonanthine (9) and folicanthine (10). In addition, this dimerization method can be expanded to the highly stereoselective synthesis of bisperhydrofuro[2,3-b]furan (5a) and the dimeric spiroketal 5b, signifying the involvement of possible radical species.

  6. Architecture of the hydrophobic and hydrophilic layers as found from crystal structure analysis of N-benzyl-N,N-dimethylalkylammonium bromides.

    PubMed

    Hodorowicz, Maciej; Stadnicka, Katarzyna; Czapkiewicz, Jan

    2005-10-01

    The molecular and crystal structures of N-benzyl-N,N-dimethylalkylammonium bromides monohydrates with chain length n=8-10 have been determined. The crystals are isostructural with the N-benzyl-N,N-dimethyldodecylammonium bromide monohydrate. The structures consist of alternated hydrophobic and hydrophilic layers perpendicular to [001]. The attraction between N+ of the cation head-groups and Br- anions is achieved through weak C_H...Br interactions. The water molecules incorporated into ionic layers are donors for two O_H...Br hydrogen bonds and serve as the acceptors in two weak interactions of C_H...O type. The methylene chains, with the slightly curved general shape, have the extended all-trans conformation. The mutual packing of the chains in the hydrophobic layers is governed by weak C_H...pi interactions.

  7. Multimetallic Catalysis Enabled Cross-Coupling of Aryl Bromides with Aryl Triflates

    PubMed Central

    Ackerman, Laura K.G.; Lovell, Matthew M.

    2015-01-01

    Transition metal-catalyzed strategies for the formation of new C-C bonds have revolutionized the field of organic chemistry, enabling the efficient synthesis of ligands, materials, and biologically active molecules.1–3 In cases where a single metal fails to promote a selective or efficient transformation, the synergistic cooperation4 of two distinct catalysts – multimetallic catalysis – can be employed instead. Many important reactions rely on multimetallic catalysis,5 including the Wacker oxidation of olefins6–8 and the Sonogashira coupling of alkynes with aryl halides.9–10 However, the application of this strategy, even in recently developed methods11, has largely been limited to the use of metals with distinct reactivities, with only one metal catalyst undergoing an oxidative addition.12 In this manuscript, we demonstrate that cooperativity between two d10 metal catalysts, (bipyridine)nickel and (1,3-bis(diphenylphosphino)propane)palladium, enables a general cross-Ullman reaction.13–15 Our method couples aryl bromides with aryl triflates directly, eliminating the use of arylmetal reagents and avoiding the challenge of differentiating between multiple C–H bonds that is required for many C–H activation methods.16–17 The selectivity does not require an excess of either substrate and originates from the orthogonal activity of the two catalysts and the relative stability of the two arylmetal intermediates. While (dppp)Pd reacts preferentially with aryl triflates to afford a persistent intermediate, (bpy)Ni reacts preferentially with aryl bromides to form a transient, reactive intermediate. Although each catalyst forms less than 5% cross product in isolation, together they are able to achieve up to 94% yield. Our results reveal a new, general method for the synthesis of biaryls, heteroaryls, and dienes, as well as a new mechanism for selective transmetalation between two catalysts. We anticipate that this reaction will simplify the synthesis of pharmaceutical agents, many of which are currently made with pre-formed organometallic reagents,1–3 and lead to the discovery of new multimetallic reactions. PMID:26280337

  8. Discharges of produced waters from oil and gas extraction via wastewater treatment plants are sources of disinfection by-products to receiving streams.

    PubMed

    Hladik, Michelle L; Focazio, Michael J; Engle, Mark

    2014-01-01

    Fluids co-produced with oil and gas production (produced waters) are often brines that contain elevated concentrations of bromide. Bromide is an important precursor of several toxic disinfection by-products (DBPs) and the treatment of produced water may lead to more brominated DBPs. To determine if wastewater treatment plants that accept produced waters discharge greater amounts of brominated DBPs, water samples were collected in Pennsylvania from four sites along a large river including an upstream site, a site below a publicly owned wastewater treatment plant (POTW) outfall (does not accept produced water), a site below an oil and gas commercial wastewater treatment plant (CWT) outfall, and downstream of the POTW and CWT. Of 29 DBPs analyzed, the site at the POTW outfall had the highest number detected (six) ranging in concentration from 0.01 to 0.09 μg L(-1) with a similar mixture of DBPs that have been detected at POTW outfalls elsewhere in the United States. The DBP profile at the CWT outfall was much different, although only two DBPs, dibromochloronitromethane (DBCNM) and chloroform, were detected, DBCNM was found at relatively high concentrations (up to 8.5 μg L(-1)). The water at the CWT outfall also had a mixture of inorganic and organic precursors including elevated concentrations of bromide (75 mg L(-1)) and other organic DBP precursors (phenol at 15 μg L(-1)). To corroborate these DBP results, samples were collected in Pennsylvania from additional POTW and CWT outfalls that accept produced waters. The additional CWT also had high concentrations of DBCNM (3.1 μg L(-1)) while the POTWs that accept produced waters had elevated numbers (up to 15) and concentrations of DBPs, especially brominated and iodinated THMs (up to 12 μg L(-1) total THM concentration). Therefore, produced water brines that have been disinfected are potential sources of DBPs along with DBP precursors to streams wherever these wastewaters are discharged. © 2013.

  9. Methyl bromide and the Montreal Protocol: An update on the critical use exemption and quarantine pre-shipment process

    Treesearch

    Scott Enebak

    2007-01-01

    Over the past 50 years, methyl bromide (MBr) has proven to be a consistently reliable pesticide that enhances seedling production and suppresses soilborne pests. It is the industry standard and an essential component of virtually every pest management program in southern forest tree nurseries. Due to the listing of MBr as a ozone depleting substance, the U.S....

  10. Mononuclear bromide complexes of Sb(V): crystal structures and thermal behaviour

    NASA Astrophysics Data System (ADS)

    Adonin, Sergey A.; Bondarenko, Mikhail A.; Samsonenko, Denis G.; Semitut, Evgeniy Yu; Sokolov, Maxim N.; Fedin, Vladimir P.

    2018-05-01

    Reactions of Sb2O3 dissolved in HBr/Br2 and bromides of pyridinium-derived cations result in mononuclear complexes of Sb(V) - (cation)[SbBr6] (cation = 2-chloropyridinium (1), 2-bromopyridinium (2)). Thermal behaviour of 1 and 2, as well as similar previously reported complexes Et4N [SbBr6] (3) and (N-EtPy)[SbBr6] (4), was studied and discussed.

  11. A comparison between a combination of ipratropium bromide plus fenoterol in a single metered dose inhaler (Duovent) and salbutamol in asthma.

    PubMed Central

    Flint, K. C.; Hockley, B.; Johnson, N. M.

    1983-01-01

    The efficacy of a single metered dose inhaler containing a combination of fenoterol (100 micrograms/puff) and ipratropium bromide (40 micrograms/puff) has been assessed in 12 asthmatics. We conclude that the bronchodilator effect of 2 puffs of the combination inhaler was significantly greater than that achieved by 2 puffs of salbutamol (100 micrograms/puff). PMID:6227877

  12. Synthesis of Improved Polyester Resins.

    DTIC Science & Technology

    1979-07-05

    p-phenylene bis(magnesium bromide) dispersed in 70 ml of hexane was added over a period of one hour. Residual Grignard reagent was washed from the...was prepared from p-phenylenedi(phenylphosphonyl chloride) (PPPC). The PPPC monomer was made from the p-phenylene bis(magnesium bromide) Grignard ...phenylphosphonyl dichloride removal. On cooling, the product was a viscous glassy liquid. It weighed 12.5 grams (113 percent based on 8g of Grignard

  13. Copper(I)-catalyzed aryl bromides to form intermolecular and intramolecular carbon-oxygen bonds.

    PubMed

    Niu, Jiajia; Guo, Pengran; Kang, Juntao; Li, Zhigang; Xu, Jingwei; Hu, Shaojing

    2009-07-17

    A highly efficient Cu-catalyzed C-O bond-forming reaction of alcohol and aryl bromides has been developed. This transformation was realized through the use of copper(I) iodide as a catalyst, 8-hydroxyquinoline as a ligand, and K(3)PO(4) as a base. A variety of functionalized substrates were found to react under these reaction conditions to provide products in good to excellent yields.

  14. WET METHOD OF PREPARING PLUTONIUM TRIBROMIDE

    DOEpatents

    Davidson, N.R.; Hyde, E.K.

    1958-11-11

    S> The preparation of anhydrous plutonium tribromide from an aqueous acid solution of plutonium tetrabromide is described, consisting of adding a water-soluble volatile bromide to the tetrabromide to provide additional bromide ions sufficient to furnish an oxidation-reduction potential substantially more positive than --0.966 volt, evaporating the resultant plutonium tribromides to dryness in the presence of HBr, and dehydrating at an elevated temperature also in the presence of HBr.

  15. Data for methyl bromide decon testing

    EPA Pesticide Factsheets

    Spreadsheets containing data for recovery of spores from different materials. Data on the fumigation parameters are also included.This dataset is associated with the following publication:Wood , J., M. Wendling, W. Richter, A. Lastivka, and L. Mickelsen. Evaluation of the Efficacy of Methyl Bromide in the Decontamination of Building and Interior Materials Contaminated with Bacillus anthracis Spores. APPLIED AND ENVIRONMENTAL MICROBIOLOGY. American Society for Microbiology, Washington, DC, USA, 1-28, (2016).

  16. Bromidotetra­kis­(2-isopropyl-1H-imidazole-κN 3)copper(II) bromide

    PubMed Central

    Godlewska, Sylwia; Socha, Joanna; Baranowska, Katarzyna; Dołęga, Anna

    2011-01-01

    The CuII atom in the title salt, [CuBr(C6H10N2)4]Br, is coordinated in a square-pyramidal geometry by four imidazole N atoms and one bromide anion that is located at the apex of the pyramid. The cations and the anions form a two-dimensional network parallel to (001) through N—H⋯Br hydrogen bonds. PMID:22064905

  17. Design and Synthesis of Novel Isoxazole Tethered Quinone-Amino Acid Hybrids

    PubMed Central

    Ravi Kumar, P.; Sambaiah, M.; Kandula, Venu; Payili, Nagaraju; Jaya Shree, A.; Yennam, Satyanarayana

    2014-01-01

    A new series of isoxazole tethered quinone-amino acid hybrids has been designed and synthesized involving 1,3-dipolar cycloaddition reaction followed by an oxidation reaction using cerium ammonium nitrate (CAN). Using this method, for the first time various isoxazole tethered quinone-phenyl alanine and quinone-alanine hybrids were synthesized from simple commercially available 4-bromobenzyl bromide, propargyl bromide, and 2,5-dimethoxybenzaldehyde in good yield. PMID:25709839

  18. Design and synthesis of novel isoxazole tethered quinone-amino Acid hybrids.

    PubMed

    Ravi Kumar, P; Behera, Manoranjan; Sambaiah, M; Kandula, Venu; Payili, Nagaraju; Jaya Shree, A; Yennam, Satyanarayana

    2014-01-01

    A new series of isoxazole tethered quinone-amino acid hybrids has been designed and synthesized involving 1,3-dipolar cycloaddition reaction followed by an oxidation reaction using cerium ammonium nitrate (CAN). Using this method, for the first time various isoxazole tethered quinone-phenyl alanine and quinone-alanine hybrids were synthesized from simple commercially available 4-bromobenzyl bromide, propargyl bromide, and 2,5-dimethoxybenzaldehyde in good yield.

  19. Volatilization Mechanism of 1-Ethyl-3-methylimidazolium Bromide Ionic Liquid (Briefing Charts)

    DTIC Science & Technology

    2012-04-01

    bromides and alkylimidazoles, presumably through alkyl abstraction via an SN2 type mechanism, and that vaporization of intact ion pairs or the formation...116.1±6.6 kJ/mol and H.‡(CH3CH2Br) = 122.9±7.2 kJ/mol, and the results are found to be in agreement with calculated values for the SN2 reactions

  20. Regular and irregular deswelling of polyacrylate and hyaluronate gels induced by oppositely charged surfactants.

    PubMed

    Nilsson, Peter; Hansson, Per

    2008-09-15

    The deswelling kinetics of macroscopic polyacrylate (PA) gels in solutions of dodecyltrimethylammonium bromide (C(12)TAB) and cetyltrimethylammonium bromide (C(16)TAB), with and without added sodium bromide, as well as hyaluronate (HA) gels in solutions of cetylpyridinium chloride (CPC) are investigated. Additional data are also provided by small-angle X-ray scattering and microgel experiments. The purpose is to study the deswelling behavior of (1) regularly deswelling gels, for which the deswelling is successfully described using a core/shell model earlier employed for microgels, and (2) irregularly deswelling gels, where the gel turns into a balloon-like structure with a dense outer layer surrounding a liquid-filled core. For regularly deswelling gels, the deswelling of PA/C(12)TAB is found to be controlled by diffusion through both stagnant layer and collapsed surface phase, while for PA/C(16)TAB it is found to be controlled mainly by the latter. The difference in deswelling rate between the two is found to correspond to the difference in surfactant diffusion coefficient in the surface phase. Factors found to promote irregular deswelling, described as balloon formation, are rapid surfactant binding, high bromide and surfactant concentration, longer surfactant chain length, and macroscopic gel size. Scattering data indicating a cubic structure for HA/CPC complexes are reported.

  1. Effects of addition of supramolecular assembly on the anatase nanocrystalline precipitation of sol-gel derived SiO2-TiO2 coating films by hot-water treatment.

    PubMed

    Katagiri, Kiyofumi; Harada, Genki; Matsuda, Atsunori; Kogure, Toshihiro; Muto, Hiroyuki; Sakai, Mototsugu

    2006-06-01

    Effects of the addition of a supramolecular assembly of cetyltrimethylammonium bromide in SiO2-TiO2 gel films on the formation of anatase type TiO2 nanocrystals with hot-water treatment were investigated. Anatase nanocrystals were formed in the whole SiO2-TiO2 gel films with the addition of cetyltrimethylammonium bromide by the treatment, whereas the nanocrystals were formed only on the film surface in the case of gel films without cetyltrimethylammonium bromide. Cetyltrimethylammonium bromide molecules in the SiO2-TiO2 gel films were completely removed by the hot-water treatment and the following UV irradiation. In the usual procedure for preparation of porous materials, the removal of template molecular assemblies required high temperature treatment over 400 degrees C. In this system, all the processes were performed at temperatures less than 100 degrees C. Additionally, the porous structure produced by the removal of micellar assembly allowed anatase nanocrystals to be formed inside the films. Therefore, the method presented in this work provides us with the novel photocatalyst coatings of porous membrane with highly-dispersed TiO2 nanocrystals via low temperature process.

  2. Interactions between soil texture and placement of dairy slurry application: I. Flow characteristics and leaching of nonreactive components.

    PubMed

    Glaesner, Nadia; Kjaergaard, Charlotte; Rubaek, Gitte H; Magid, Jakob

    2011-01-01

    Land application of manure can exacerbate nutrient and contaminant transfers to the aquatic environment. This study examined the effect of injecting a dairy cattle (Bostaurus L.) manure slurry on mobilization and leaching of dissolved, nonreactive slurry components across a range of agricultural soils. We compared leaching of slurry-applied bromide through intact soil columns (20 cm diam., 20 cm high) of differing textures following surface application or injection of slurry. The volumetric fraction of soil pores >30 microm ranged from 43% in a loamy sand to 28% in a sandy loam and 15% in a loam-textured soil. Smaller active flow volumes and higher proportions of preferential flow were observed with increasing soil clay content. Injection of slurry in the loam soil significantly enhanced diffusion of applied bromide into the large fraction of small pores compared with surface application. The resulting physical protection against leaching of bromide was reflected by 60.2% of the bromide tracer was recovered in the effluent after injection, compared with 80.6% recovery after surface application. No effect of slurry injection was observed in the loamy sand and sandy loam soils. Our findings point to soil texture as an important factor influencing leaching of dissolved, nonreactive slurry components in soils amended with manure slurry.

  3. Atmospheric volatilization of methyl bromide, 1,3-dichloropropene, and propargyl bromide through two plastic films: transfer coefficient and temperature effect

    NASA Astrophysics Data System (ADS)

    Wang, D.; Yates, S. R.; Gan, J.; Knuteson, J. A.

    Atmospheric emission of methyl bromide (MeBr) and its potential alternative chemicals such as 1,3-dichloropropene (1,3-D) and propargyl bromide (PrBr) can contribute to air pollution and ozone depletion (for MeBr). One of the main sources of these chemicals is from agricultural soil fumigation. To understand the volatilization dynamics, emission of MeBr, 1,3-D, and PrBr through a polyethylene-based high-barrier film (HBF) and a virtually impermeable film (VIF) was measured using an air flow and sampling system that produced >90% mass balance. The experiment was conducted outdoors and was subjected to ambient daily temperature variations. The HBF film was found to be very permeable to 1,3-D and PrBr, but somewhat less permeable to MeBr. The VIF film was very impermeable to 1,3-D, PrBr, or MeBr. Measured volatilization flux, in general, exhibited strong diurnal variations which were controlled by film temperature. Unlike the HBF film, a time lag (˜12 h) was observed between high-temperatures and high-emission flux values for the VIF film. An impermeable film may be used as an effective means of controlling the atmospheric emission of MeBr and its alternative chemicals.

  4. A reconnaissance analysis of groundwater quality in the Eagle Ford shale region reveals two distinct bromide/chloride populations.

    PubMed

    Hildenbrand, Zacariah L; Carlton, Doug D; Meik, Jesse M; Taylor, Josh T; Fontenot, Brian E; Walton, Jayme L; Henderson, Drew; Thacker, Jonathan B; Korlie, Stephanie; Whyte, Colin J; Hudak, Paul F; Schug, Kevin A

    2017-01-01

    The extraction of oil and natural gas from unconventional shale formations has prompted a series of investigations to examine the quality of the groundwater in the overlying aquifers. Here we present a reconnaissance analysis of groundwater quality in the Eagle Ford region of southern Texas. These data reveal two distinct sample populations that are differentiable by bromide/chloride ratios. Elevated levels of fluoride, nitrate, sulfate, various metal ions, and the detection of exotic volatile organic compounds highlight a high bromide group of samples, which is geographically clustered, while encompassing multiple hydrogeological strata. Samples with bromide/chloride ratios representative of connate water displayed elevated levels of total organic carbon, while revealing the detection of alcohols and chlorinated compounds. These findings suggest that groundwater quality in the Western Gulf Basin is, for the most part, controlled by a series of natural processes; however, there is also evidence of episodic contamination events potentially attributed to unconventional oil and gas development or other anthropogenic activities. Collectively, this characterization of natural groundwater constituents and exogenous compounds will guide targeted remediation efforts and provides insight for agricultural entities, industrial operators, and rural communities that rely on groundwater in southern Texas. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Programmable Colloidal Approach to Hierarchical Structures of Methylammonium Lead Bromide Perovskite Nanocrystals with Bright Photoluminescent Properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Teunis, Meghan B.; Johnson, Merrell A.; Muhoberac, Barry B.

    Here, systematic tailoring of nanocrystal architecture could provide unprecedented control over their electronic, photophysical, and charge transport properties for a variety of applications. However, at present, manipulation of the shape of perovskite nanocrystals is done mostly by trial-and-error-based experimental approaches. Here, we report systematic colloidal synthetic strategies to prepare methylammonium lead bromide quantum platelets and quantum cubes. In order to control the nucleation and growth processes of these nano crystals, we appropriately manipulate the solvent system, surface ligand chemistry, and reaction temperature causing syntheses into anisotropic shapes. We demonstrate that both the presence of chlorinated solvent and a long chainmore » aliphatic amine in the reaction mixture are crucial for the formation of ultrathin quantum platelets (similar to 1.5 nm in thickness), which is driven by mesoscale-assisted growth of spherical seed nanocrystals (similar to 1.6 nm in diameter) through attachment of monomers onto selective crystal facets. A combined surface and structural characterization, along with small-angle X-ray scattering analysis, confirm that the long hydrocarbon of the aliphatic amine is responsible for the well ordered hierarchical stacking of the quantum platelets of 3.5 nm separation. In contrast, the formation of similar to 12 nm edge-length quantum cubes is a kinetically driven process in which a high flux of monomers is achieved by supplying thermal energy. The photoluminescence quantum yield of our quantum platelets (similar to 52%) is nearly 2-fold higher than quantum cubes. Moreover, the quantum platelets display a lower nonradiative rate constant than that found with quantum cubes, which suggests less surface trap states. Together, our research has the potential both to improve the design of synthetic methods for programmable control of shape and assembly and to provide insight into optoelectronic properties of these materials for solid-state device fabrication, e.g., light-emitting diodes, solar cells, and lasing materials.« less

  6. BSA modification to reduce CTAB induced nonspecificity and cytotoxicity of aptamer-conjugated gold nanorods

    NASA Astrophysics Data System (ADS)

    Yasun, Emir; Li, Chunmei; Barut, Inci; Janvier, Denisse; Qiu, Liping; Cui, Cheng; Tan, Weihong

    2015-05-01

    Aptamer-conjugated gold nanorods (AuNRs) are excellent candidates for targeted hyperthermia therapy of cancer cells. However, in high concentrations of AuNRs, aptamer conjugation alone fails to result in highly cell-specific AuNRs due to the presence of positively charged cetyltrimethylammonium bromide (CTAB) as a templating surfactant. Besides causing nonspecific electrostatic interactions with the cell surfaces, CTAB can also be cytotoxic, leading to uncontrolled cell death. To avoid the nonspecific interactions and cytotoxicity triggered by CTAB, we report the further biologically inspired modification of aptamer-conjugated AuNRs with bovine serum albumin (BSA) protein. Following this modification, interaction between CTAB and the cell surface was efficiently blocked, thereby dramatically reducing the side effects of CTAB. This approach may provide a general and simple method to avoid one of the most serious issues in biomedical applications of nanomaterials: nonspecific binding of the nanomaterials with biological cells.Aptamer-conjugated gold nanorods (AuNRs) are excellent candidates for targeted hyperthermia therapy of cancer cells. However, in high concentrations of AuNRs, aptamer conjugation alone fails to result in highly cell-specific AuNRs due to the presence of positively charged cetyltrimethylammonium bromide (CTAB) as a templating surfactant. Besides causing nonspecific electrostatic interactions with the cell surfaces, CTAB can also be cytotoxic, leading to uncontrolled cell death. To avoid the nonspecific interactions and cytotoxicity triggered by CTAB, we report the further biologically inspired modification of aptamer-conjugated AuNRs with bovine serum albumin (BSA) protein. Following this modification, interaction between CTAB and the cell surface was efficiently blocked, thereby dramatically reducing the side effects of CTAB. This approach may provide a general and simple method to avoid one of the most serious issues in biomedical applications of nanomaterials: nonspecific binding of the nanomaterials with biological cells. Electronic supplementary information (ESI) available: Fig. S-1 to S-6 are included. See DOI: 10.1039/c5nr01704a

  7. Programmable Colloidal Approach to Hierarchical Structures of Methylammonium Lead Bromide Perovskite Nanocrystals with Bright Photoluminescent Properties

    DOE PAGES

    Teunis, Meghan B.; Johnson, Merrell A.; Muhoberac, Barry B.; ...

    2017-04-05

    Here, systematic tailoring of nanocrystal architecture could provide unprecedented control over their electronic, photophysical, and charge transport properties for a variety of applications. However, at present, manipulation of the shape of perovskite nanocrystals is done mostly by trial-and-error-based experimental approaches. Here, we report systematic colloidal synthetic strategies to prepare methylammonium lead bromide quantum platelets and quantum cubes. In order to control the nucleation and growth processes of these nano crystals, we appropriately manipulate the solvent system, surface ligand chemistry, and reaction temperature causing syntheses into anisotropic shapes. We demonstrate that both the presence of chlorinated solvent and a long chainmore » aliphatic amine in the reaction mixture are crucial for the formation of ultrathin quantum platelets (similar to 1.5 nm in thickness), which is driven by mesoscale-assisted growth of spherical seed nanocrystals (similar to 1.6 nm in diameter) through attachment of monomers onto selective crystal facets. A combined surface and structural characterization, along with small-angle X-ray scattering analysis, confirm that the long hydrocarbon of the aliphatic amine is responsible for the well ordered hierarchical stacking of the quantum platelets of 3.5 nm separation. In contrast, the formation of similar to 12 nm edge-length quantum cubes is a kinetically driven process in which a high flux of monomers is achieved by supplying thermal energy. The photoluminescence quantum yield of our quantum platelets (similar to 52%) is nearly 2-fold higher than quantum cubes. Moreover, the quantum platelets display a lower nonradiative rate constant than that found with quantum cubes, which suggests less surface trap states. Together, our research has the potential both to improve the design of synthetic methods for programmable control of shape and assembly and to provide insight into optoelectronic properties of these materials for solid-state device fabrication, e.g., light-emitting diodes, solar cells, and lasing materials.« less

  8. Synthetic lead bromapatite: X-ray structure at ambient pressure and compressibility up to about 20 GPa

    NASA Astrophysics Data System (ADS)

    Liu, Xi; Fleet, Michael E.; Shieh, Sean R.; He, Qiang

    2011-05-01

    Lead bromapatite [Pb10(PO4)6Br2] has been synthesized via solid-state reaction at pressures up to 1.0 GPa, and its structure determined by single-crystal X-ray diffraction at ambient temperature and pressure. The large bromide anion is accommodated in the c-axis channel by lateral displacements of structural elements, particularly of Pb2 cations and PO4 tetrahedra. The compressibility of bromapatite was also investigated up to about 20.7 GPa at ambient temperature, using a diamond-anvil cell and synchrotron X-ray radiation. The compressibility of lead bromapatite is significantly different from that of lead fluorapatite. The pressure-volume data of lead bromapatite ( P < 10 GPa) fitted to the third-order Birch-Murnaghan equation yield an isothermal bulk modulus ( K T ) of 49.8(16) GPa and first pressure derivative ( KT^' } ) of 10.1(10). If KT^' } is fixed at 4, the derived K T is 60.8(11) GPa. The relative difference of the bulk moduli of these two lead apatites is thus about 12%, which is about two times the relative difference of the bulk moduli (~5%) of the calcium apatites fluorapatite [Ca10(PO4)6F2], chlorapatite [Ca10(PO4)6Cl2] and hydroxylapatite [Ca10(PO4)6(OH)2]. Another interesting feature apparently related to the replacement of F by Br in lead apatite is the switch in the principle axes of the strain ellipsoid: the c-axis is less compressible than the a-axis in lead bromapatite but more compressible in lead fluorapatite.

  9. Ultrafast carrier dynamics in bimetallic nanostructure-enhanced methylammonium lead bromide perovskites.

    PubMed

    Zarick, Holly F; Boulesbaa, Abdelaziz; Puretzky, Alexander A; Talbert, Eric M; DeBra, Zachary R; Soetan, Naiya; Geohegan, David B; Bardhan, Rizia

    2017-01-26

    In this work, we examine the impact of hybrid bimetallic Au/Ag core/shell nanostructures on the carrier dynamics of methylammonium lead tribromide (MAPbBr 3 ) mesoporous perovskite solar cells (PSCs). Plasmon-enhanced PSCs incorporated with Au/Ag nanostructures demonstrated improved light harvesting and increased power conversion efficiency by 26% relative to reference devices. Two complementary spectral techniques, transient absorption spectroscopy (TAS) and time-resolved photoluminescence (trPL), were employed to gain a mechanistic understanding of plasmonic enhancement processes. TAS revealed a decrease in the photobleach formation time, which suggests that the nanostructures improve hot carrier thermalization to an equilibrium distribution, relieving hot phonon bottleneck in MAPbBr 3 perovskites. TAS also showed a decrease in carrier decay lifetimes, indicating that nanostructures enhance photoinduced carrier generation and promote efficient electron injection into TiO 2 prior to bulk recombination. Furthermore, nanostructure-incorporated perovskite films demonstrated quenching in steady-state PL and decreases in trPL carrier lifetimes, providing further evidence of improved carrier injection in plasmon-enhanced mesoporous PSCs.

  10. Charge Transport between Coupling Colloidal Perovskite Quantum Dots Assisted by Functional Conjugated Ligands.

    PubMed

    Dai, Jinfei; Xi, Jun; Li, Lu; Zhao, JingFeng; Shi, Yifei; Zhang, Wenwen; Ran, Chenxin; Jiao, Bo; Hou, Xun; Duan, Xinhua; Wu, Zhaoxin

    2018-05-14

    Long alkyl-chain capping ligands are indispensable for preparing stable colloidal quantum dots. However, its insulating feature blocks efficient carrier transport among QDs, leading to inferior performance in light-emitting diodes (LEDs). The trade-off between conductivity and colloidal stability of QDs has now been overcome. Methylamine lead bromide (MAPbBr 3 ) QDs with a conjugated alkyl-amine, 3-phenyl-2-propen-1-amine (PPA), as ligands were prepared. Owing to electron cloud overlapping and the delocalization effect of conjugated molecules, the conductivity and carrier mobility of PPA-QDs films increased almost 22 times over that of OA-QD films without compromising colloidal stability and photoluminescence. PPA-QDs LEDs exhibit a maximum current efficiency of 9.08 cd A -1 , which is 8 times of that of OA-QDs LEDs (1.14 cd A -1 ). This work provides critical solution for the poor conductivity of QDs in applications of energy-related devices. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Surface Plasmon Resonance Effect in Inverted Perovskite Solar Cells.

    PubMed

    Cui, Jin; Chen, Cheng; Han, Junbo; Cao, Kun; Zhang, Wenjun; Shen, Yan; Wang, Mingkui

    2016-03-01

    This work reports on incorporation of spectrally tuned gold/silica (Au/SiO 2 ) core/shell nanospheres and nanorods into the inverted perovskite solar cells (PVSC). The band gap of hybrid lead halide iodide (CH 3 NH 3 PbI 3 ) can be gradually increased by replacing iodide with increasing amounts of bromide, which can not only offer an appreciate solar radiation window for the surface plasmon resonance effect utilization, but also potentially result in a large open circuit voltage. The introduction of localized surface plasmons in CH 3 NH 3 PbI 2.85 Br 0.15 -based photovoltaic system, which occur in response to electromagnetic radiation, has shown dramatic enhancement of exciton dissociation. The synchronized improvement in photovoltage and photocurrent leads to an inverted CH 3 NH 3 PbI 2.85 Br 0.15 planar PVSC device with power conversion efficiency of 13.7%. The spectral response characterization, time resolved photoluminescence, and transient photovoltage decay measurements highlight the efficient and simple method for perovskite devices.

  12. Degradation of Highly Alloyed Metal Halide Perovskite Precursor Inks: Mechanism and Storage Solutions

    DOE PAGES

    Dou, Benjia; Wheeler, Lance M.; Christians, Jeffrey A.; ...

    2018-03-14

    Whereas the promise of metal halide perovskite (MHP) photovoltaics (PV) is that they can combine high efficiency with solution-processability, the chemistry occurring in precursor inks is largely unexplored. Herein, we investigate the degradation of MHP solutions based on the most widely used solvents, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). For the MHP inks studied, which contain formamidinium (FA+), methylammonium (MA+), cesium (Cs+), lead (Pb2+), bromide (Br-), and iodide (I-), dramatic compositional changes are observed following storage of the inks in nitrogen in the dark. We show that hydrolysis of DMF in the precursor solution forms dimethylammonium formate, which subsequently incorporatesmore » into the MHP film to compromise the ability of Cs+ and MA+ to stabilize FA+-based MHP. The changes in solution chemistry lead to a modification of the perovskite film stoichiometry, band gap, and structure. The solid precursor salts are stable when ball-milled into a powder, allowing for the storage of large quantities of stoichiometric precursor materials.« less

  13. Degradation of Highly Alloyed Metal Halide Perovskite Precursor Inks: Mechanism and Storage Solutions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dou, Benjia; Wheeler, Lance M.; Christians, Jeffrey A.

    Whereas the promise of metal halide perovskite (MHP) photovoltaics (PV) is that they can combine high efficiency with solution-processability, the chemistry occurring in precursor inks is largely unexplored. Herein, we investigate the degradation of MHP solutions based on the most widely used solvents, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). For the MHP inks studied, which contain formamidinium (FA+), methylammonium (MA+), cesium (Cs+), lead (Pb2+), bromide (Br-), and iodide (I-), dramatic compositional changes are observed following storage of the inks in nitrogen in the dark. We show that hydrolysis of DMF in the precursor solution forms dimethylammonium formate, which subsequently incorporatesmore » into the MHP film to compromise the ability of Cs+ and MA+ to stabilize FA+-based MHP. The changes in solution chemistry lead to a modification of the perovskite film stoichiometry, band gap, and structure. The solid precursor salts are stable when ball-milled into a powder, allowing for the storage of large quantities of stoichiometric precursor materials.« less

  14. Intranasal Insulin: A Novel Treatment for Gulf War Multisymptom Illness

    DTIC Science & Technology

    2013-10-01

    pyridostigmine bromide . Fort Detrick, MD: US Army Medical Research and Material Command. Li B, Mahan CM, Kang HK, Eisen SA, Engel CC. (2011, July 27...Sullivan K, Krengel M, Proctor SP, Devine S, Heeren T, White RF. (2003). Cognitive functioning in treatment-seeking Gulf War veterans: pyridostigmine ... bromide use and PTSD. Journal of Psychopathology and Behavioral Assessment. 25(2):95-103. Tillman GD, Green TA, Ferree TC, Calley CS, Maguire MJ

  15. Nitroethylation of Vinyl Triflates and Bromides

    PubMed Central

    Padilla–Salinas, Rosaura; Walvoord, Ryan R.; Tcyrulnikov, Sergei

    2013-01-01

    A two-carbon homologation of vinyl triflates and bromides for the synthesis of homoallylic nitro products is described. This palladium-catalyzed double coupling of nitromethane exploits the anion stabilizing and leaving group properties of nitromethane, generating the homo allyl nitro products via a tandem cross-coupling/π-allylation sequence. The resultant process provides a mild and convenient entry of nitroethylated products, which are versatile precursors to β,γ-unsaturated carbonyls, homoallylic amines, and nitrile oxides. PMID:23885976

  16. The history and future of methyl bromide alternatives used in the production of forest seedlings in the southern United States

    Treesearch

    Scott A. Enebak

    2013-01-01

    This paper gives a brief history of the Southern Forest Nursery Management Cooperative’s (SFNMC) efforts in testing methyl bromide (MBr) alternatives for soil fumigation. In the southeastern United States, fumigation with MBr has been the most commonly used method for producing high quality, pest-free forest-tree seedlings in an environment that is conducive for soil-...

  17. [Affinity between CrIII and purified DNA, studied by competition with an intercalating agent: ethidium bromide].

    PubMed

    Vecchio, D; Balbi, C; Russo, P; Parodi, S; Santi, L

    1981-05-30

    The affinity between CrIII and purified calf- thymus DNA was studied at neutral pH by competition with ethidium bromide. Competition results indicated an affinity between CrIII and DNA of the order of 10(5) 1/mole. These results are in good agreement with previous results CrIII - DNA affinity was studied by the independent method of equilibrium dialysis and chromium dosage by atomic spectrometry.

  18. Pyridostimine Bromide 30mg Stability in Extended Storage Conditions

    DTIC Science & Technology

    2017-12-03

    limit 100 words): Pyridostigmine bromide 30mg is approved by the Federal Drug Administration (FDA) as a pre -treatment of nerve gas exposure. The...under controlled temperatu,re and humidity. The tablets will be tested at 0, 3, 4, 5, and 6 months after removal from refrigerator when stored at both...Guidance definitions of storage conditions required for stability testing to obtain new drug approval in different climate zones in the world. At

  19. Cardiovascular effects of pancuronium bromide in mongrel dogs.

    PubMed

    Reitan, J A; Warpinski, M A

    1975-09-01

    The cardiovascular effects of a new nondepolarizing muscle relaxant, pancuronium bromide, were studied in mongrel dogs. Small, but significant, increases in mean arterial blood pressure were observed after each of 2 intravenous doses (0.01 mg/kg and 0.1 mg/kg) were given. Heart rate increased significantly in dogs administered the larger dosage, and indexes of ventricular functions demonstrated a trend toward positive cardiac inotrophy after either the large or the small dose.

  20. Aluminum electroplating on steel from a fused bromide electrolyte

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Prabhat K. Tripathy; Laura A. Wurth; Eric J. Dufek

    A quaternary bromide bath (LiBr–KBr–CsBr–AlBr3) was used to electro-coat aluminum on steel substrates. The electrolytewas prepared by the addition of AlBr3 into the eutectic LiBr–KBr–CsBr melt. A smooth, thick, adherent and shiny aluminum coating could be obtained with 80 wt.% AlBr3 in the ternary melt. The SEM photographs of the coated surfaces suggest the formation of thick and dense coatings with good aluminum coverage. Both salt immersion and open circuit potential measurement suggested that the coatings did display a good corrosionresistance behavior. Annealing of the coated surfaces, prior to corrosion tests, suggested the robustness of the metallic aluminum coating inmore » preventing the corrosion of the steel surfaces. Studies also indicated that the quaternary bromide plating bath can potentially provide a better aluminumcoating on both ferrous and non-ferrous metals, including complex surfaces/geometries.« less

  1. Limited remyelination of CNS axons by Schwann cells transplanted into the sub-arachnoid space.

    PubMed

    Blakemore, W F

    1984-06-01

    Areas of primary demyelination which did not subsequently remyelinate spontaneously were prepared in the cat spinal cord by injecting small volumes of ethidium bromide into tissue which had previously been exposed to 40 Grays of X-irradiation. Autologous peripheral nerve tissue was placed in the sub-arachnoid space over such lesions, either at the time of injecting ethidium bromide, or at 14 days or 28 days after injecting ethidium bromide. The extent of Schwann cell remyelination was assessed 28 days after transplantation. In no case were all the demyelinated axons remyelinated; rather, remyelination was limited to axons near to blood vessels. It was concluded that Schwann cells migrated from the transplanted tissue into the lesion via the perivascular space and that they failed to remyelinate the bulk of demyelinated axons because of an absence within the CNS of suitable extracellular matrix.

  2. Aluminium Electroplating on Steel from a Fused Bromide Electrolyte

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Prabhat Tripathy; Laura Wurth; Eric Dufek

    A quaternary bromide bath (LiBr-KBr-CsBr-AlBr3) was used to electro-coat aluminium on steel substrates. The electrolyte was prepared by the addition of AlBr3 into the eutectic LiBr-KBr-CsBr melt. A smooth, thick, adherent and shiny aluminium coating could be obtained with 80 wt.% AlBr3 in the ternary melt. The SEM photographs of the coated surfaces suggest the formation of thick and dense coatings with good aluminium coverage. Both salt immersion and open circuit potential measurement suggest that the coatings did display good corrosion-resistance behavior. Annealing of the coated surfaces, prior to corrosion tests, suggested the robustness of the metallic aluminium coating inmore » preventing the corrosion of the steel surfaces. Studies also indicated that the quaternary bromide plating bath can potentially provide a better aluminium coating on both ferrous and non-ferrous metals, including complex surfaces/geometries.« less

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sathyalakshmi, R.; Bhagavannarayana, G.; Ramasamy, P.

    L-(+)-Glutamic acid hydro bromide, an isomorphic salt of L-glutamic acid hydrochloride, was synthesized and the synthesis was confirmed using Fourier transform infrared analysis. Solubility of the material in water was determined. L-Glutamic acid hydro bromide crystals were grown by low temperature solution growth using the solvent evaporation technique. Single crystal X-ray diffraction studies were carried out and the cell parameters, atomic co-ordinates, bond lengths and bond angles were reported. High-resolution X-ray diffraction studies were carried out and good crystallinity for the grown crystal was observed from the diffraction curve. The grown crystals were subjected to dielectric studies. Ultraviolet-visible-near infrared spectralmore » analysis shows good optical transmission in the visible and infrared region of the grown crystals. The second harmonic generation efficiency of L-glutamic acid hydro bromide crystal was determined using the Kurtz powder test and it was found that it had efficiency comparable with that of the potassium di-hydrogen phosphate crystal.« less

  4. Enhancement effect on the chemiluminescence of acridinium esters under neutral conditions.

    PubMed

    Nakazono, Manabu; Nanbu, Shinkoh

    2018-03-01

    Enhancement effect on the chemiluminescence of acridinium ester derivatives under neutral conditions was investigated. Additions of phenols did not enhance the chemiluminescence intensities of acridinium ester derivatives in the presence of horseradish peroxidase and hydrogen peroxide. Additions of cetyltrimethylammonium bromide apparently enhanced the chemiluminescence intensities of phenyl 10-methyl-10λ 4 -acridine-9-carboxylate derivatives with electron-withdrawing groups at the 4-position of the phenyl group. In particular, the chemiluminescence intensity of 4-(trifluoromethyl)phenyl 10-methyl-10λ 4 -acridine-9-carboxylate trifluoromethanesulfonate salt was 5.5 times stronger in the presence of cetyltrimethylammonium bromide than in its absence at pH 7. The chemiluminescence intensity of 3,4-dicyano-phenyl 10-methyl-10λ 4 -acridine-9-carboxylate trifluoromethanesulfonate salt was 46 times stronger in the presence of cetyltrimethylammonium bromide at pH 7 than in its absence at pH 10. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Stepwise cycloaddition reaction of N-phenacylbenzothiazolium bromides and nitroalkenes for tetrahydro-, dihydro- and benzo[d]pyrrolo[2,1-b]thiazoles

    NASA Astrophysics Data System (ADS)

    Jin, Gong; Sun, Jing; Yang, Ren-Yin; Yan, Chao-Guo

    2017-04-01

    The triethylamine promoted stepwise 1,3-dipolar cycloaddition reaction of N-phenacylbenzothiazolium bromides with nitroalkenes in ethanol resulted in a mixture of two isomeric tetrahydrobenzo[d]pyrrolo[2,1-b]thiazoles with cis/trans/cis- and all-trans-configurations. More importantly, the corresponding dihydrobenzo[d]pyrrolo[2,1-b]thiazoles can be selectively prepared in refluxing ethanol and the benzo[d]pyrrolo[2,1-b]thiazoles can be obtained in satisfactory yields by sequential dehydrogenation with DDQ as oxidizer. On the other hand, the similar cycloaddition reaction of N-phenacylbenzothiazolium bromides with 1-methy-1-nitroalkenes in refluxing ethanol afforded benzo[d]pyrrolo[2,1-b]thiazoles with splitting out of nitro group. The stereochemistry of the spiro compounds was clearly elucidated on the basis of NMR spectra and sixteen single crystal structures.

  6. One-pot palladium-catalyzed synthesis of sulfonyl fluorides from aryl bromides† †Electronic supplementary information (ESI) available: Experimental details and supporting characterisation data. See DOI: 10.1039/c6sc03924c Click here for additional data file.

    PubMed Central

    Davies, Alyn T.; Curto, John M.

    2017-01-01

    A mild, efficient synthesis of sulfonyl fluorides from aryl and heteroaryl bromides utilizing palladium catalysis is described. The process involves the initial palladium-catalyzed sulfonylation of aryl bromides using DABSO as an SO2 source, followed by in situ treatment of the resultant sulfinate with the electrophilic fluorine source NFSI. This sequence represents the first general method for the sulfonylation of aryl bromides, and offers a practical, one-pot alternative to previously described syntheses of sulfonyl fluorides, allowing rapid access to these biologically important molecules. Excellent functional group tolerance is demonstrated, with the transformation successfully achieved on a number of active pharmaceutical ingredients, and their precursors. The preparation of peptide-derived sulfonyl fluorides is also demonstrated. PMID:28451264

  7. Potential impacts of imposing methyl bromide phaseout on US strawberry growers: a case study of a nomination for a critical use exemption under the Montreal Protocol.

    PubMed

    Norman, Catherine S

    2005-04-01

    The Montreal Protocol on Substances that Deplete the Ozone Layer requires developed countries to phaseout methyl bromide production and non-quarantine uses by 2005 and developing countries to do the same by 2015. Exemptions to phaseout have been significant in slowing the process of abatement; many countries have applied for exemptions for some uses, partly on grounds that phaseout is economically infeasible. Data on the US strawberry market are used to investigate grower costs arising from substitution away from methyl bromide, the impact of trends in and characteristics of the demand for fresh strawberries, and characteristics of trade with countries not yet required to eliminate use of the compound. It appears that actual net costs to growers will be much smaller than the simple increase in production costs cited in the US nomination for exemption.

  8. Processes affecting the dissipation of the herbicide isoxaflutole and its diketonitrile metabolite in agricultural soils under field conditions.

    PubMed

    Papiernik, Sharon K; Yates, Scott R; Koskinen, William C; Barber, Brian

    2007-10-17

    Two-year field dissipation studies were conducted in three soil types in Minnesota to examine the processes affecting the dissipation of the herbicide isoxaflutole and its phytotoxic diketonitrile metabolite (DKN) under relatively cool, wet soil conditions. Plots of cuphea were treated with isoxaflutole and potassium bromide, a nonsorbed, nondegraded tracer. Replicate soil cores were collected six times during the growing season to a depth of 1 m, and the bromide or herbicide concentration was measured in each of five depth increments. The dissipation half-life (DT50) of isoxaflutole + DKN was 8-18 days in each soil. Bromide and herbicide concentrations were low at depths >40 cm throughout the study, and herbicide concentrations in soil 100 days after application were usually undetectable. Simulation modeling using Hydrus-1D for the loam soil suggested that plant uptake was an important mechanism of dissipation.

  9. Synthesis and bio-physicochemical properties of amide-functionalized N-methylpiperazinium surfactants.

    PubMed

    Chauhan, Vinay; Singh, Sukhprit; Mishra, Rachana; Kaur, Gurcharan

    2014-12-15

    Four new amide functionalized N-methylpiperazinium amphiphiles having tetradecyl, hexadecyl alkyl chain lengths and counterions; chloride or bromide have been synthesized and characterized by various spectroscopic techniques. These new surfactants have been investigated in detail for their self-assembling behavior by surface tension, conductivity and fluorescence measurements. The thermodynamic parameters of these surfactants indicate that micellization is exothermic and entropy-driven. The dynamic light scattering (DLS) and transmission electron microscopy (TEM) experiments have been performed to insight the aggregate size of these cationics. Thermal degradation of these new surfactants has also been evaluated by thermal gravimetric analysis (TGA). These new surfactants form stable complexes with DNA as acknowledged by agarose gel electrophoresis, ethidium bromide exclusion and zeta potential measurements. They have also been found to have low cytotoxicity by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on the C6 glioma cell line. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. The colorimetric detection of Pb2+ by using sodium thiosulfate and hexadecyl trimethyl ammonium bromide modified gold nanoparticles.

    PubMed

    Zhang, Yujie; Leng, Yumin; Miao, Lijing; Xin, Junwei; Wu, Aiguo

    2013-04-21

    A simple, rapid colorimetric detection method for Pb(2+) in aqueous solution has been developed by using sodium thiosulfate (Na2S2O3) and hexadecyl trimethyl ammonium bromide (CTAB) modified gold nanoparticles (Au NPs). Na2S2O3 was added into the Au NP solution and thiosulfate ions (S2O3(2-)) were adsorbed on the surface of the Au NPs due to electrostatic interactions. Au atoms on the surface of the Au NPs were then oxidized to Au(i) by the O2 that existed in the solution in presence of thiosulfate. The addition of Pb(2+) (the final concentration was lower than 10 μM), accelerated the leaching of the Au NPs, and Pb-Au alloys also formed on the surface of the Au NPs. There was an obvious decrease in the surface plasmon resonance (SPR) absorption of the Au NPs. The lowest concentration for Pb(2+) that could be detected by the naked eye was 0.1 μM and using UV-vis spectroscopy was 40 nM. This is lower than the lead toxic level defined by the US Environmental Protection Agency (US EPA), which is 75 nM. In this method, CTAB, as a stabilizing agent for Au NPs, can accelerate the adsorption of S2O3(2-) on the surface of the Au NPs, which shortened the detection time to within 30 min. Moreover, this detection method is simple, cheap and environmentally friendly.

  11. Photodegradation routes of the herbicide bromoxynil in solution and sorbed on silica nanoparticles.

    PubMed

    Escalada, Juan P; Arce, Valeria B; Carlos, Luciano; Porcal, Gabriela V; Biasutti, M Alicia; Criado, Susana; García, Norman A; Mártire, Daniel O

    2014-04-01

    Some organic contaminants dissolved in natural waters tend to adsorb on suspended particles and sediments. In order to mimic the photodegradation routes in natural waters of bromoxynil (BXN) adsorbed on silica, we here prepare and characterize silica nanoparticles modified with BXN (NP-BXN). We measure the direct photolysis quantum yield of aqueous BXN at 307 nm (0.064 ± 0.001) and detect the formation of bromide ions as a reaction product. Under similar conditions the photolysis quantum yield of BXN bonded to NP-BXN is much lower (0.0021 ± 0.0004) and does not lead to formation of bromide ions. The rate constant of the reaction of NP-BXN with the excited triplet states of riboflavin, a molecule employed as a proxy of chromophore dissolved organic matter (DOM) was measured in laser flash-photolysis experiments. The rate constants for the overall (kt) and chemical interaction (kr) of singlet oxygen with NP-BXN were also measured. Kinetic computer simulations show that the relevance of the direct and indirect (through reactions with reactive species generated in photoinduced processes) photodegradation routes of BXN is very much affected by sorption on silica. Immobilization of the herbicide on the particles, on one hand, affects the photolysis mechanism and lowers its photolysis quantum yield. On the other hand, the results obtained in aqueous suspensions indicate that immobilization also lowers the rate of collisional encounter, which affects the quenching rate constants of excited triplet states and singlet oxygen with the herbicide.

  12. Color-Pure Violet-Light-Emitting Diodes Based on Layered Lead Halide Perovskite Nanoplates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liang, Dong; Peng, Yuelin; Fu, Yongping

    Violet electroluminescence is rare in both inorganic and organic light-emitting diodes (LEDs). Low-cost and room- temperature solution-processed lead halide perovskites with high- efficiency and color-tunable photoluminescence are promising for LEDs. Here, we report room-temperature color-pure violet LEDs based on a two-dimensional lead halide perovskite material, namely, 2-phenylethylammonium (C 6H 5CH 2CH 2NH 3 +, PEA) lead bromide [(PEA) 2PbBr 4]. The natural quantum confinement of two-dimen- sional layered perovskite (PEA) 2PbBr 4 allows for photoluminescence of shorter wavelength (410 nm) than its three-dimensional counterpart. By converting as-deposited polycrystalline thin films to micrometer-sized (PEA) 2PbBr 4 nanoplates using solvent vapor annealing,more » we successfully integrated this layered perovskite material into LEDs and achieved efficient room-temperature violet electroluminescence at 410 nm with a narrow bandwidth. This conversion to nanoplates significantly enhanced the crystallinity and photophysical properties of the (PEA) 2PbBr 4 samples and the external quantum efficiency of the violet LED. Finally, the solvent vapor annealing method reported herein can be generally applied to other perovskite materials to increase their grain size and, ultimately, improve the performance of optoelectronic devices based on perovskite materials.« less

  13. Color-Pure Violet-Light-Emitting Diodes Based on Layered Lead Halide Perovskite Nanoplates

    DOE PAGES

    Liang, Dong; Peng, Yuelin; Fu, Yongping; ...

    2016-06-23

    Violet electroluminescence is rare in both inorganic and organic light-emitting diodes (LEDs). Low-cost and room- temperature solution-processed lead halide perovskites with high- efficiency and color-tunable photoluminescence are promising for LEDs. Here, we report room-temperature color-pure violet LEDs based on a two-dimensional lead halide perovskite material, namely, 2-phenylethylammonium (C 6H 5CH 2CH 2NH 3 +, PEA) lead bromide [(PEA) 2PbBr 4]. The natural quantum confinement of two-dimen- sional layered perovskite (PEA) 2PbBr 4 allows for photoluminescence of shorter wavelength (410 nm) than its three-dimensional counterpart. By converting as-deposited polycrystalline thin films to micrometer-sized (PEA) 2PbBr 4 nanoplates using solvent vapor annealing,more » we successfully integrated this layered perovskite material into LEDs and achieved efficient room-temperature violet electroluminescence at 410 nm with a narrow bandwidth. This conversion to nanoplates significantly enhanced the crystallinity and photophysical properties of the (PEA) 2PbBr 4 samples and the external quantum efficiency of the violet LED. Finally, the solvent vapor annealing method reported herein can be generally applied to other perovskite materials to increase their grain size and, ultimately, improve the performance of optoelectronic devices based on perovskite materials.« less

  14. Magnetically induced orientation of mesochannels in mesoporous silica films at 30 tesla.

    PubMed

    Yamauchi, Yusuke; Sawada, Makoto; Komatsu, Masaki; Sugiyama, Atsushi; Osaka, Tetsuya; Hirota, Noriyuki; Sakka, Yoshio; Kuroda, Kazuyuki

    2007-12-03

    We demonstrate the magnetically induced orientation of mesochannels in mesoporous silica films prepared with low-molecular-weight surfactants under an extremely high magnetic field of 30 T. This process is principally applicable to any type of surfactant that has magnetic anisotropy because such a high magnetic field provides sufficient magnetic energy for smooth magnetic orientation. Hexadecyltrimethylammonium bromide (CTAB) and polyoxyethylene-10-cetyl ether (Brij 56) were used as cationic and nonionic surfactants, respectively. According to XRD and cross-sectional TEM, mesochannels aligned perpendicular to the substrates were observed in films prepared with low-molecular-weight surfactants, although the effect was incomplete. The evolution of these types of films should lead to future applications such as highly sensitive chemical sensors and selective separation.

  15. Generation of Benzyne Species from Diphenylphosphoryl Derivatives: Simultaneous Exchange of Three Functional Groups.

    PubMed

    Gorobets, Evgueni; Parvez, Masood; Derksen, Darren J; Keay, Brian A

    2016-06-13

    Interaction of (2-diphenylphosphoryl-3-iodo-4-methoxy-phenyl) methanol with NaH in DMF at ambient temperature results in the generation of benzyne intermediates that can be trapped by furan or DMF. Trapping with DMF forms 3-(dimethylaminomethyl)-2-hydroxy-6-methoxybenzaldehyde demonstrating the simultaneous exchange of three functionalities in a single step. The presence of the alkoxy substituent adjacent to iodine is critical for high regioselectivity addition of DMF. The corresponding bromide or triflate can be used in place of the iodide with equal efficiency. This methodology was used to synthesize the reported structure of gigasol and leading to a structural reassignment of this biscoumarin natural product. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. The role of Pif1p, a DNA helicase in Saccharomyces cerevisiae, in maintaining mitochondrial DNA.

    PubMed

    Cheng, Xin; Dunaway, Stephen; Ivessa, Andreas S

    2007-05-01

    Mitochondrial DNA (mtDNA) is highly susceptible to oxidative and chemically induced damage, and these insults lead to a number of diseases. In Saccharomyces cerevisiae, the DNA helicase Pif1p is localized to the nucleus and mitochondria. We show that pif1 mutant cells are sensitive to ethidium bromide-induced damage and this mtDNA is prone to fragmentation. We also show that Pif1p associates with mtDNA. In pif1 mutant cells, mtDNA breaks at specific sites that exhibit Pif1-dependent recombination. We conclude that Pif1p participates in the protection from double-stranded (ds) DNA breaks or alternatively in the repair process of dsDNA breaks in mtDNA.

  17. Self-tuning multivariable pole placement control of a multizone crystal growth furnace

    NASA Technical Reports Server (NTRS)

    Batur, C.; Sharpless, R. B.; Duval, W. M. B.; Rosenthal, B. N.

    1992-01-01

    This paper presents the design and implementation of a multivariable self-tuning temperature controller for the control of lead bromide crystal growth. The crystal grows inside a multizone transparent furnace. There are eight interacting heating zones shaping the axial temperature distribution inside the furnace. A multi-input, multi-output furnace model is identified on-line by a recursive least squares estimation algorithm. A multivariable pole placement controller based on this model is derived and implemented. Comparison between single-input, single-output and multi-input, multi-output self-tuning controllers demonstrates that the zone-to-zone interactions can be minimized better by a multi-input, multi-output controller design. This directly affects the quality of crystal grown.

  18. In vitro Cell Viability by CellProfiler® Software as Equivalent to MTT Assay.

    PubMed

    Gasparini, Luciana S; Macedo, Nayana D; Pimentel, Elisângela F; Fronza, Marcio; Junior, Valdemar L; Borges, Warley S; Cole, Eduardo R; Andrade, Tadeu U; Endringer, Denise C; Lenz, Dominik

    2017-07-01

    This study evaluated in vitro cell viability by the colorimetric MTT stands for 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay compared to image analysis by CellProfiler ® software. Hepatoma (Hepa-1c1c7) and fibroblast (L929) cells were exposed to isolated substances, camptothecin, lycorine, tazettine, albomaculine, 3-epimacronine, trispheridine, galanthine and Padina gymnospora , Sargassum sp. methanolic extract, and Habranthus itaobinus Ravenna ethyl acetate in different concentrations. After MTT assay, cells were stained with Panotic dye kit. Cell images were obtained with an inverted microscope equipped with a digital camera. The images were analyzed by CellProfiler ® . No cytotoxicity at the highest concentration analyzed for 3-epimacronine, albomaculine, galanthine, trispheridine, P. gymnospora extract and Sargassum sp. extract where detected. Tazettine offered cytotoxicity only against the Hepa1c1c7 cell line. Lycorine, camptothecin, and H. itaobinus extract exhibited cytotoxic effects in both cell lines. The viability methods tested were correlated demonstrated by Bland-Atman test with normal distribution with mean difference between the two methods close to zero, bias value 3.0263. The error was within the limits of the confidence intervals and these values had a narrow difference. The correlation between the two methods was demonstrated by the linear regression plotted as R 2 . CellProfiler ® image analysis presented similar results to the MTT assay in the identification of viable cells, and image analysis may assist part of biological analysis procedures. The presented methodology is inexpensive and reproducible. In vitro cell viability assessment with MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay may be replaced by image analysis by CellProfiler ® . The viability methods tested were correlated demonstrated by Bland-Atman test with normal distribution with mean difference between the two methods close to zero, bias value 3.0263. The correlation between the two methods was demonstrated by the linear regression plotted as R2. Abbreviations: HPLC: High pressure liquid chromatography MTT: (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide).

  19. Synthesis and application of imidazolium-based ionic liquids as extraction solvent for pretreatment of triazole fungicides in water samples.

    PubMed

    Yang, Jiale; Fan, Chen; Kong, Dandan; Tang, Gang; Zhang, Wenbing; Dong, Hongqiang; Liang, You; Wang, Deng; Cao, Yongsong

    2018-02-01

    Five novel ionic liquids (ILs), 1,3-dibutylimidazolium bromide [BBMIm][Br], 1-pentyl-3-butylimidazolium bromide [BPMIm][Br], 1-hexyl-3-butylimidazolium bromide [BHMIm][Br], 1,1'-(butane-1,4-diyl)bis(3-butylimidazolium) bromide [C 4 (BMIm) 2 ][Br 2 ], and 1,1'-(butane-1,4-diyl)bis(3-methylimidazolium) bromide [C 4 (MIm) 2 ][Br 2 ], were prepared and used in situ to react with bis(trifluoromethane)sulfonamide lithium salt to extract the myclobutanil, tebuconazole, cyproconazole, and prothioconazole from water samples. The results showed that mono-cationic ILs had much better recovery than dicationic ILs, and mono-imidazolium IL bearing butyl groups at N-1 and N-3 sites had the best recovery. When the length of the alkyl substituent group was more than four carbons at N-3 site, the recovery decreased with increase of alkyl chain length of 1-butylimidazolium IL. The extraction efficiency order of triazoles from high to low was [BBMIm][Br], [BPMIm][Br], [BHMIm][Br], [BMIm][Br] (1-butyl-3-methylimidazolium bromide), [C 4 (BMIm) 2 ]Br 2 , [C 4 (MIm) 2 ]Br 2 . An in situ ionic liquid dispersive liquid-liquid microextraction combined with ultrasmall superparamagnetic Fe 3 O 4 was established as a pretreatment method for enrichment of triazole fungicides in water samples by using the synthetic [BBMIm][Br] as the cationic IL and used to detect analytes followed by high-performance liquid chromatography. Under the optimized conditions, the proposed method showed a good linearity within a range of 5-250 μg L -1 , with the determination coefficient (r 2 ) varying from 0.998 to 0.999. High mean enrichment factors were achieved ranging from 187 to 323, and the recoveries of the target analytes from real water samples at spiking levels of 10.0, 20.0, and 50.0 μg L -1 were between 70.1% and 115.0%. The limits of detection for the analytes were 0.74-1.44 μg L -1 , and the intra-day relative standard deviations varied from 5.23% to 8.65%. The proposed method can be further applied to analyze and monitor pesticides in other related samples. Graphical Abstract The scheme of the in-situ DLLME method for the determination of triazoles using the imidazolium-based ionic liquids.

  20. 49 CFR 173.193 - Bromoacetone, methyl bromide, chloropicrin and methyl bromide or methyl chloride mixtures, etc.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... fiberboard boxes with inside metal cans containing not over one pound each, or inside metal cans with a... packaged as follows in metal boxes (4A, 4B or 4N) or wooden boxes (4C1, 4C2, 4D or 4F) with inner glass... mm (0.5 inch) of absorbent material. Total amount of liquid in the outer box must not exceed 11 kg...

  1. 49 CFR 173.193 - Bromoacetone, methyl bromide, chloropicrin and methyl bromide or methyl chloride mixtures, etc.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... fiberboard boxes with inside metal cans containing not over one pound each, or inside metal cans with a... packaged as follows in metal boxes (4A, 4B or 4N) or wooden boxes (4C1, 4C2, 4D or 4F) with inner glass... mm (0.5 inch) of absorbent material. Total amount of liquid in the outer box must not exceed 11 kg...

  2. WRAIR Protocols for Soldier Status and Readiness to Organophosphate Exposure: Unprocessed Whole Blood Cholinesterase and Pyridostigmine Bromide Quantification

    DTIC Science & Technology

    2003-07-01

    blood in the presence and absence of selective ( huperzine - a and Iso-OMPA), and non-selective (pyridostigmine bromide) cholinesterase inhibitors...cholinesterases after exposure to CWAs such as GD and pharmaceuticals such as huperzine - a and pyridostigmine have been determined in animals and man...activity. Since urban terrorism is on the rise, Federal,State, and local authorities need a reliable, fast, inexpensive method for confirming such an

  3. Projecting Medical Supply Requirements for a Highly Mobile Forward Resuscitative Surgery System

    DTIC Science & Technology

    1999-10-01

    Sulfate Injection 0.5MG/ML 20ML Vial 6505013859409 Ephedrine Sulfate Injection 50MG/ML Ampoules 100S 6505012385634 Epinephrine Injection 1ML Syringe...Container 12S 6505010410558 Theopental Sodium Injection 500MG Vial 25S 6505012582004 Vecuronium Bromide Injection IMG/ML 10ML Vial 10S...Sterile 1GM Container 12S 6505012582004 Vecuronium Bromide Injection IMG/ML 10ML Vial 10S 6135009857845 Battery Nonrechargeable 1.5Volt Size AA 24S

  4. RNA extraction from various recalcitrant plant tissues with a cethyltrimethylammonium bromide-containing buffer followed by an acid guanidium thiocyanate-phenol-chloroform treatment.

    PubMed

    Suzuki, Yuji; Mae, Tadahiko; Makino, Amane

    2008-07-01

    High-quality total RNA was extracted using a cethyltrimethylammonium bromide-containing buffer followed by an acid guanidium thiocyanate-phenol-chloroform treatment from recalcitrant plant tissues such as tree leaves (pine, Norway spruce, ginkgo, Japanese cedar, rose), flowers (rose, Lotus japonicus) and storage tissues (seeds of Lotus japonicus and rice, sweet potato tuber, banana fruit). This protocol greatly reduced the time required for RNA extraction.

  5. The Underpotential Deposition of Copper on Pt(311): Site Selective Deposition and Anion Effects

    DTIC Science & Technology

    1994-03-14

    water (18 MOhms Millipore Milli-Q water). Aqueous acid solutions were prepared from high-purity (ULTREX) sulfuric acid . Copper ion solutions were...prepared by dissolution of CuSO 4 .5H 2 0 (Aldrich Gold Label 5N5) in sulfuric acid solutions. Chloride and bromide containing solutions were prepared by...Voltammetric characteristics of a Pt(311) electrode in acidic solutions containing chloride and bromide. Fig. 1 shows cyclic voltammograxns for the

  6. Thermal Decomposition Mechanism of 1-ethyl-3-methylimidazolium Bromide Ionic Liquid (Preprint)

    DTIC Science & Technology

    2011-09-14

    TetraethylammoniumTrifluoromentanesulfonate Ionic Liquid and Neutralized Nafion 117 for High-Temperature Fuel Cells J. Am. Chem. Soc. 2010, 132, 2183-2195. (7) Kim, S. Y.; Kim, S...bromide 5b. GRANT NUMBER ionic liquid (Preprint) 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Steven D. Chambreau, Jerry A. Boatz, Ghanshyam L. Vaaghjiani...In order to better understand the volatilization process for ionic liquids , the vapor evolved from heating the ionic liquid 1-ethyl-3

  7. [Cetyltrimethylammonium bromide for fluorescence enhancement of anhydrotetracycline hydrochloride and iso-tetracycline].

    PubMed

    Zha, Jian-peng; Lin, Ying; Yang, Xing-hui; Hou, Hai-ni; Wei, Tie-jun; Chen, Xing-li

    2002-06-01

    Fluorescence enhancement of anhydrotetracycline hydrochloride and iso-tetracycline has been described. The fluorescence intensities of anhydrotetracycline hydrochloride and iso-tetracycline with cetyltrimethylammonium bromide (CTMAB) enhanced by micellar solution have been examined. It is found that fluorescence enhancement of anhydrotetracycline hydrochloride and iso-tetracycline depends on the concentration of CTMAB and pH of the solution. It can be used to develop sensitive methods for the determination of tetracycline hydrochloride and its decomposition product.

  8. Bis(2,2'-bipyridyl-κN,N')(carbonato-κO,O')cobalt(III) bromide trihydrate.

    PubMed

    Ma, Peng-Tao; Wang, Yu-Xia; Zhang, Guo-Qian; Li, Ming-Xue

    2007-12-06

    The title complex, [Co(CO(3))(C(10)H(8)N(2))(2)]Br·3H(2)O, is isostructural with the chloride analogue. The six-coordinated octahedral [Co(2,2'-bipy)(2)CO(3)](+) cation (2,2'-bipy is 2,2'-bipyrid-yl), bromide ion and water mol-ecules are linked together via O-H⋯Br and O-H⋯O hydrogen bonds, generating a one-dimensional chain.

  9. Role of physical heterogeneity in the interpretation of small-scale laboratory and field observations of bacteria, microbial-sized microsphere, and bromide transport through aquifer sediments

    USGS Publications Warehouse

    Harvey, Ronald W.; Kinner, Nancy E.; MacDonald, Dan; Metge, David W.; Bunn, Amoret

    1993-01-01

    The effect of physical variability upon the relative transport behavior of microbial-sized microspheres, indigenous bacteria, and bromide was examined in field and flow-through column studies for a layered, but relatively well sorted, sandy glaciofluvial aquifer. These investigations involved repacked, sieved, and undisturbed aquifer sediments. In the field, peak abundance of labeled bacteria traveling laterally with groundwater flow 6 m downgradient from point of injection was coincident with the retarded peak of carboxylated microspheres (retardation factor, RF = 1.7) at the 8.8 m depth, but preceded the bromide peak and the retarded microsphere peak (RF = 1.5) at the 9.0 m depth. At the 9.5 m depth, the bacterial peak was coincident with both the bromide and the microsphere peaks. Although sorption appeared to be a predominant mechanism responsible for immobilization of microbial-sized microspheres in the aquifer, straining appeared to be primarily responsible for their removal in 0.6-m-long columns of repacked, unsieved aquifer sediments. The manner in which the columns were packed also affected optimal size for microsphere transport, which in one experiment was near the size of the small (∼2 μm) groundwater protozoa (flagellates). These data suggest that variability in aquifer sediment structure can be important in interpretation of both small-scale field and laboratory experiments examining microbial transport behavior.

  10. The discovery and development of aclidinium bromide for the treatment of chronic obstructive pulmonary disease.

    PubMed

    Malerba, Mario; Radaeli, Alessandro; Santini, Giuseppe; Morjaria, Jaymin; Mores, Nadia; Mondino, Chiara; Macis, Giuseppe; Montuschi, Paolo

    2018-06-01

    Bronchodilators, including long-acting muscarinic receptor antagonists (LAMAs), are a mainstay of the pharmacological treatment of chronic obstructive pulmonary disease (COPD). LAMAs act as bronchodilators principally by antagonizing airway smooth muscle cells M 3 muscarinic receptors. Aclidinium bromide is a twice-daily LAMA which was developed to improve on the efficacy and/or safety of previous LAMAs. Area covered: Herein, the authors present the pharmacotherapeutic role of aclidinium in COPD and point out unmet need in this research area. The following aspects are covered: a) the discovery and medicinal chemistry of aclidinium bromide; b) an overview of the market; c) its mechanism of action; d) its pharmacokinetic/pharmacodynamic profile derived from pre-clinical studies; e) the clinical studies which led to its licensing; f) the evidence from meta-analyses; g) the aclidinium/formoterol fixed dose combination for COPD and h) priorities in this area of research. Expert opinion: Aclidinium bromide has the pharmacological properties, safety and efficacy profile and inhaler characteristics which makes it a valuable therapeutic option for pharmacological management of patients with COPD. Due to its rapid biotransformation into inactive metabolites, aclidinium is potentially one of the safest LAMAs. Further head-to-head randomized clinical trials are required to define efficacy and safety of aclidinium when compared to once-daily LAMAs. The clinical relevance of airway anti-remodeling effects of aclidinium has to be defined.

  11. Bromide-free TEMPO-mediated oxidation of primary alcohol groups in starch and methyl alpha-D-glucopyranoside.

    PubMed

    Bragd, P L; Besemer, A C; van Bekkum, H

    2000-09-22

    TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl)-mediated oxidation of potato starch and methyl alpha-D-glucopyranoside (MGP) was performed in the absence of sodium bromide (NaBr) as co-catalyst, solely using sodium hypochlorite (NaOCl) as the primary oxidant. The low reaction rate associated with a bromide-free process was increased by performing the oxidation at increased temperatures. The reaction proceeded stoichiometrically and with high selectivity and with only minor depolymerisation, provided that temperature and pH were kept < or = 20 degrees C and < 9.0, respectively. At 20 degrees C and pH 8.5, the reaction rate was comparable to that of a corresponding oxidation catalysed by NaBr at 2 degrees C. Consequently, this is a simple approach to raise the TEMPO/NaOCl reaction rate under bromide-free conditions while still maintaining good product properties. At higher oxidation temperatures (> or = 25 degrees C) and under more alkaline conditions (pH > or = 9.0) degradation of the starch skeleton occurred. Simultaneously, side-reactions of the nitrosonium ion lowered the yield of the oxidation. Despite the absence of the NaBr catalyst, the reaction rate-controlling step was found to be the oxidation of the primary hydroxyl groups with the nitrosonium ion. The reaction was first-order in MGP and in TEMPO.

  12. Palladium-Catalyzed Coupling of Ammonia with Aryl Chlorides, Bromides, Iodides and Sulfonates: A General Method for the Preparation of Primary Arylamines

    PubMed Central

    Vo, Giang D.

    2010-01-01

    We report that the complex generated from Pd[P(o-tol)3]2 and the alkylbisphosphine CyPF-t-Bu is a highly active and selective catalyst for the coupling of ammonia with aryl chlorides, bromides, iodides, and sulfonates. The couplings of ammonia with this catalyst conducted with a solution of ammonia in dioxane form primary arylamines from a variety of aryl electrophiles in high yields. Catalyst loadings as low as 0.1 mol % were sufficient for reactions of many aryl chlorides and bromides. In the presence of this catalyst, aryl sulfonates also coupled with ammonia for the first time in high yields. A comparison of reactions in the presence of this catalyst versus those in the presence of existing copper and palladium systems revealed a complementary, if not broader substrate scope. The utility of this method to generate amides, imides and carbamates is illustrated by a one-pot synthesis of a small library of these carbonyl compounds from aryl bromides and chlorides. Mechanistic studies show that Pd[P(o-tol)3]2 and CyPF-t-Bu generate a more active and general catalyst than that generated from CyPF-t-Bu and palladiun(II) precursors because of the low concentration of active catalyst that is generated from the combination of palladium(II), ammonia and base. PMID:19591470

  13. What is your diagnosis? Marked hyperchloremia in a dog.

    PubMed

    Piperisova, Ida; Neel, Jennifer A; Papich, Mark G

    2009-09-01

    A 5-year-old neutered male Cavalier King Charles Spaniel was evaluated for a 3-week history of progressive paresis. The dog had been receiving potassium citrate capsules to acidify urine for the past 2 years because of an earlier history of urolithiasis. Results of neurologic examination, spinal cord radiography, and magnetic resonance imaging of the skull and spinal cord revealed no lesions that could have accounted for the neurologic signs. The main abnormalities on a clinical chemistry profile were marked hyperchloremia (179 mmol/L, reference interval 108-122 mmol/L) and an anion gap of -50.4 mmol/L (reference interval 16.3-28.6 mmol/L). Because of the severe hyperchloremia, serum bromide concentration was measured (400 mg/dL; toxic concentration >150 mg/dL; some dogs may tolerate up to 300 mg/dL). Analysis of the potassium citrate capsules, which had been compounded at a local pharmacy, yielded a mean bromide concentration of 239 mg/capsule. Administration of the capsules was discontinued and there was rapid resolution of the dog's neurologic signs. This case of extreme bromide toxicity, which apparently resulted from inadvertent use of bromide instead of citrate at the pharmacy, illustrates the importance of knowing common interferents with analyte methodologies and of pursing logical additional diagnostic tests based on clinical and laboratory evidence, even when a patient's history appears to rule out a potential etiology.

  14. Trends in bromide wet deposition concentrations in the contiguous United States, 2001-2016.

    PubMed

    Wetherbee, Gregory A; Lehmann, Christopher M B; Kerschner, Brian M; Ludtke, Amy S; Green, Lee A; Rhodes, Mark F

    2018-02-01

    Bromide (Br - ) and other solute concentration data from wet deposition samples collected and analyzed by the National Atmospheric Deposition Program (NADP) from 2001 to 2016, were statistically analyzed for trends both geographically and temporally by precipitation type. Analysis was limited to NADP sites in the contiguous 48 United States. The Br - concentrations for this time period had a high number of values censored at the detection limits with greater than 86 percent of sample concentrations below analytical detection. Bromide was more frequently detected at NADP sites in coastal regions. Analysis using specialized statistical techniques for censored data revealed that Br - concentrations varied by precipitation type with higher concentrations usually observed in liquid versus precipitation containing snow. Negative temporal trends in Br - wet deposition concentrations were observed at a majority of NADP sites; approximately 25 percent of these trend values were statistically significant at less than 0.05 to 0.10 significance levels. Potential causes for the negative trends were explored, including annual and seasonal changes in precipitation depth, reduced emissions of methyl bromide (CH 3 Br) from coastal wetlands, and declining industrial use of bromine compounds. The results indicate that Br - in non-coastal wet-deposition comes mainly from long-range transport, not local sources. Correlations between Br - , chloride, and nitrate concentrations also were evaluated. Published by Elsevier Ltd.

  15. Effect of phytosanitary irradiation and methyl bromide fumigation on the physical, sensory, and microbiological quality of blueberries and sweet cherries.

    PubMed

    Thang, Karen; Au, Kimberlee; Rakovski, Cyril; Prakash, Anuradha

    2016-10-01

    The objective of this study was to determine whether irradiation could serve as a suitable phytosanitary treatment alternative to methyl bromide (MB) fumigation for blueberries and sweet cherry and also to determine the effect of phytosanitary irradiation treatment on survival of Salmonella spp. and Listeria monocytogenes on these fruit. 'Bluecrop' blueberries (Vaccinium corymbosum) and 'Sweetheart' cherries (Prunus avium) were irradiated at 0.4 kGy or fumigated with methyl bromide and evaluated for quality attributes during storage. Irradiation caused an immediate decrease in firmness of both fruit without further significant change during storage. Fumigated fruit, in contrast, softened by 11-14% during storage. Irradiation did not adversely affect blueberry and cherry shelf-life. MB fumigation did not impact blueberry and cherry quality attributes initially; however, fumigated fruit exhibited greater damage and mold growth than the control and irradiated samples during storage. Irradiation at 400 Gy resulted in a ∼1 log CFU g(-1) reduction in Salmonella spp. and Listeria monocytogenes counts, indicating that this treatment cannot significantly enhance safety. This study indicates that irradiation at a target dose of 0.4 kGy for phytosanitary treatment does not negatively impact blueberry and cherry quality and can serve as an alternative to methyl bromide fumigation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  16. Absorbed dose in AgBr in direct film for photon energies ( < 150 keV): relation to optical density. Theoretical calculation and experimental evaluation.

    PubMed

    Helmrot, E; Alm Carlsson, G

    1996-01-01

    In the radiological process it is necessary to develop tools so as to explore how X-rays can be used in the most effective way. Evaluation of models to derive measures of image quality and risk-related parameters is one possibility of getting such a tool. Modelling the image receptor, an important part of the imaging chain, is then required. The aim of this work was to find convenient and accurate ways of describing the blackening of direct dental films by X-rays. Since the beginning of the 20th century, the relation between optical density and photon interactions in the silver bromide in X-ray films has been investigated by many authors. The first attempts used simple quantum theories with no consideration of underlying physical interaction processes. The theories were gradually made more realistic by the introduction of dosimetric concepts and cavity theory. A review of cavity theories for calculating the mean absorbed dose in the AgBr grains of the film emulsion is given in this work. The cavity theories of GREENING (15) and SPIERS-CHARLTON (37) were selected for calculating the mean absorbed dose in the AgBr grains relative to the air collision kerma (Kc,air) of the incident photons of Ultra-speed and Ektaspeed (intraoral) films using up-to-date values of interaction coefficients. GREENING'S theory is a multi-grain theory and the results depend on the relative amounts of silver bromide and gelatine in the emulsion layer. In the single grain theory of SPIERS-CHARLTON, the shape and size of the silver bromide grain are important. Calculations of absorbed dose in the silver bromide were compared with measurements of optical densities in Ultra-speed and Ektaspeed films for a broad range (25-145 kV) of X-ray energy. The calculated absorbed dose values were appropriately averaged over the complete photon energy spectrum, which was determined experimentally using a Compton spectrometer. For the whole range of tube potentials used, the measured optical densities of the films were found to be proportional to the mean absorbed dose in the AgBr grains calculated according to GREENING'S theory. They were also found to be proportional to the collision kerma in silver bromide (Kc,AgBr) indicating proportionality between Kc,AgBr and the mean absorbed dose in silver bromide. While GREENING'S theory shows that the quotient of the mean absorbed dose in silver bromide and Kc,AgBr varies with photon energy, this is not apparent when averaged over the broad (diagnostic) X-ray energy spectra used here. Alternatively, proportionality between Kc,AgBr and the mean absorbed dose in silver bromide can be interpreted as resulting from a combination of the SPIERS-CHARLTON theory, valid at low photon energies ( < 30 keV) and GREENING'S theory, which is strictly valid at energies above 50 keV. This study shows that the blackening of non-screen films can be related directly to the energy absorbed in the AgBr grains of the emulsion layer and that, for the purpose of modelling the imaging chain in intraoral radiography, film response can be represented by Kc,AgBr (at the position of the film) independent of photon energy. The importance of taking the complete X-ray energy spectrum into full account in deriving Kc,AgBr is clearly demonstrated, showing that the concept of effective energy must be used with care.

  17. Mechanism of HERG potassium channel inhibition by tetra-n-octylammonium bromide and benzethonium chloride

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Long, Yan; Lin, Zuoxian; Xia, Menghang

    Tetra-n-octylammonium bromide and benzethonium chloride are synthetic quaternary ammonium salts that are widely used in hospitals and industries for the disinfection and surface treatment and as the preservative agent. Recently, the activities of HERG channel inhibition by these compounds have been found to have potential risks to induce the long QT syndrome and cardiac arrhythmia, although the mechanism of action is still elusive. This study was conducted to investigate the mechanism of HERG channel inhibition by these compounds by using whole-cell patch clamp experiments in a CHO cell line stably expressing HERG channels. Tetra-n-octylammonium bromide and benzethonium chloride exhibited concentration-dependentmore » inhibitions of HERG channel currents with IC{sub 50} values of 4 nM and 17 nM, respectively, which were also voltage-dependent and use-dependent. Both compounds shifted the channel activation I–V curves in a hyperpolarized direction for 10–15 mV and accelerated channel activation and inactivation processes by 2-fold. In addition, tetra-n-octylammonium bromide shifted the inactivation I–V curve in a hyperpolarized direction for 24.4 mV and slowed the rate of channel deactivation by 2-fold, whereas benzethonium chloride did not. The results indicate that tetra-n-octylammonium bromide and benzethonium chloride are open-channel blockers that inhibit HERG channels in the voltage-dependent, use-dependent and state-dependent manners. - Highlights: ► Tetra-n-octylammonium and benzethonium are potent HERG channel inhibitors. ► Channel activation and inactivation processes are accelerated by the two compounds. ► Both compounds are the open-channel blockers to HERG channels. ► HERG channel inhibition by both compounds is use-, voltage- and state dependent. ► The in vivo risk of QT prolongation needs to be studied for the two compounds.« less

  18. To compare the effect of camylofin dihydrochloride (anafortin) with combination of valethamate bromide (epidosin) and hyoscine butyl-N-bormide (buscopan) on cervical dilation.

    PubMed

    Sarbhjit, Kaur; S K, Bajwa; Parmjit, Kaur; Surinder, Bhupal

    2013-09-01

    Various drugs have been tried to hasten cervical dilatation so that problems and hazards of prolonged labour both for the mother and fetus are minimised without increasing maternal or perinatal mortality and morbidity. To compare the effect of camylofin dihydrochloride with combination of valethemate bromide (epidosin) & hyoscine N butyl bromide (buscopan) on cervical dilatation, evaluate the incidence of side effects and to look for neonatal outcome. Two hundred cases were included of primigravidae or multigravidae with gestational age of 37 to 40 weeks with full term with single foetus,vertex presentation and no major antenatal complication of women in labour, admitted to labour room of gynaecology Department, Government Medical College, Patiala, India, was studied and divided into 2 groups Group A-100 Cases - labour accelerated by camylofin dihydro chloride and Group B-100 Cases-labour accelerated by valethemate bromide (epidosin) and hyoscine N butyl bromide. The mean age, parity and period of gestation in Anafortan group was 24.13 ± 3.60 years, 49% primigravidae and 51% multigravidae and 38.81 ± 1.09 weeks, while that in Epidosin + Buscopan group was 24.43 ± 3.42 years, 45% primigravidae and 51% multigravidae and 38.94 ± 1.09 weeks respectively. The difference was insignificant and both the groups were comparable. Mean duration of Active phase of 1st stage of labor was 141.40 ± 55.41 minutes in Anafortan group and 181.46 ± 75.58 minutes in Epidosin + Buscopan group. Mean rate of cervical dilatation according to active phase of first stage was 3.33 ± 1.03 cm/hours in Anafortan group and 2.69 ± 1.03 cm/hr in Epidosin + Buscopan group. The difference between the two groups is highly significant (p < 0.01) thus it is concluded that Anafortan hastened the rate of cervical dilatation.

  19. To Compare the Effect of Camylofin Dihydrochloride (Anafortin) with Combination of Valethamate Bromide (Epidosin) and Hyoscine Butyl-N-Bormide (Buscopan) on Cervical Dilation

    PubMed Central

    Sarbhjit, Kaur; S.K., Bajwa; Parmjit, Kaur; Surinder, Bhupal

    2013-01-01

    Background: Various drugs have been tried to hasten cervical dilatation so that problems and hazards of prolonged labour both for the mother and fetus are minimised without increasing maternal or perinatal mortality and morbidity. Aims and Objectives: To compare the effect of camylofin dihydrochloride with combination of valethemate bromide (epidosin) & hyoscine N butyl bromide (buscopan) on cervical dilatation, evaluate the incidence of side effects and to look for neonatal outcome. Material and Methods: Two hundred cases were included of primigravidae or multigravidae with gestational age of 37 to 40 weeks with full term with single foetus,vertex presentation and no major antenatal complication of women in labour, admitted to labour room of gynaecology Department, Government Medical College, Patiala, India, was studied and divided into 2 groups Group A–100 Cases – labour accelerated by camylofin dihydro chloride and Group B–100 Cases–labour accelerated by valethemate bromide (epidosin) and hyoscine N butyl bromide. Observations: The mean age, parity and period of gestation in Anafortan group was 24.13 ± 3.60 years, 49% primigravidae and 51% multigravidae and 38.81 ± 1.09 weeks, while that in Epidosin + Buscopan group was 24.43 ± 3.42 years, 45% primigravidae and 51% multigravidae and 38.94 ± 1.09 weeks respectively. The difference was insignificant and both the groups were comparable. Results: Mean duration of Active phase of 1st stage of labor was 141.40 ± 55.41 minutes in Anafortan group and 181.46 ± 75.58 minutes in Epidosin + Buscopan group. Mean rate of cervical dilatation according to active phase of first stage was 3.33 ± 1.03 cm/hours in Anafortan group and 2.69 ± 1.03 cm/hr in Epidosin + Buscopan group. The difference between the two groups is highly significant (p < 0.01) thus it is concluded that Anafortan hastened the rate of cervical dilatation. PMID:24179892

  20. Effect of chronic administration of phenobarbital, or bromide, on pharmacokinetics of levetiracetam in dogs with epilepsy.

    PubMed

    Muñana, K R; Nettifee-Osborne, J A; Papich, M G

    2015-01-01

    Levetiracetam (LEV) is a common add-on antiepileptic drug (AED) in dogs with refractory seizures. Concurrent phenobarbital administration alters the disposition of LEV in healthy dogs. To evaluate the pharmacokinetics of LEV in dogs with epilepsy when administered concurrently with conventional AEDs. Eighteen client-owned dogs on maintenance treatment with LEV and phenobarbital (PB group, n = 6), LEV and bromide (BR group, n = 6) or LEV, phenobarbital and bromide (PB-BR group, n = 6). Prospective pharmacokinetic study. Blood samples were collected at 0, 1, 2, 4, and 6 hours after LEV administration. Plasma LEV concentrations were determined by high-pressure liquid chromatography. To account for dose differences among dogs, LEV concentrations were normalized to the mean study dose (26.4 mg/kg). Pharmacokinetic analysis was performed on adjusted concentrations, using a noncompartmental method, and area-under-the-curve (AUC) calculated to the last measured time point. Compared to the PB and PB-BR groups, the BR group had significantly higher peak concentration (Cmax ) (73.4 ± 24.0 versus 37.5 ± 13.7 and 26.5 ± 8.96 μg/mL, respectively, P < .001) and AUC (329 ± 114 versus 140 ± 64.7 and 98.7 ± 42.2 h*μg/mL, respectively, P < .001), and significantly lower clearance (CL/F) (71.8 ± 22.1 versus 187 ± 81.9 and 269 ± 127 mL/h/kg, respectively, P = .028). Concurrent administration of PB alone or in combination with bromide increases LEV clearance in epileptic dogs compared to concurrent administration of bromide alone. Dosage increases might be indicated when utilizing LEV as add-on treatment with phenobarbital in dogs. Copyright © 2015 by the American College of Veterinary Internal Medicine.

  1. Use of bromide:Chloride ratios to differentiate potential sources of chloride in a shallow, unconfined aquifer affected by brackish-water intrusion

    USGS Publications Warehouse

    Andreasen, D.C.; Fleck, W.B.

    1997-01-01

    Brackish water from Chesapeake Bay and its tributaries has entered the Aquia aquifer in east-central Anne Arundel County, Maryland, USA. This determination was made based on chloride analyses of water samples collected in wells screened in the Aquia aquifer between October 1988 and May 1989. The Aquia aquifer, which is composed of fine- to medium-grained sand, is a shallow, unconfined aquifer in this area. Land use is primarily urban, consisting of a mixture of residential and light commercial areas. Associated with the urban setting is the potential for chloride contamination to enter the Aquia aquifer from anthropogenic sources, such as residential septic-tank effluent, leaky public sewer lines, road-deicing salt, stormwater infiltration basins, and domestic water-conditioning recharge effluent. In order to map the distribution of bay-water intrusion in the Aquia aquifer, chloride derived from Chesapeake Bay was differentiated from chloride derived from anthropogenic sources by comparing the ratio of dissolved bromide to dissolved chloride (bromide:chloride) in groundwater to the distinctive ratio in Chesapeake Bay water. Two additional factors considered in determining the source of the chloride were nitrogen concentrations and well-screen positions of sampled wells in relation to the estimated depth of the fresh-water/brackish-water interface. Of 36 Aquia-aquifer water samples with chloride concentrations greater than 30 mg/L, 22 had bromide:chloride ratios similar to the ratio in Chesapeake Bay water, an indication that bay water is the primary source of the chloride. Of the other 14 samples with bromide:chloride ratios dissimilar to the ratio in Chesapeake Bay water, seven were from wells where screen positions were substantially above the estimated fresh-water/brackish-water interface. Three of these samples had nitrogen concentrations (as nitrite plus nitrate) greater than 3.0 mg/L, an indication that chloride in these groundwater samples comes from anthropogenic sources, at least in part.

  2. By-products formation during degradation of isoproturon in aqueous solution. II: Chlorination.

    PubMed

    Mascolo, G; Lopez, A; James, H; Fielding, M

    2001-05-01

    After a previous study in which the considered oxidant was ozone (Part I), a laboratory investigation has been carried out to study the degradation of the herbicide isoproturon during its reaction with another oxidant, i.e. chlorine, in aqueous solution (Part II; this paper). The specific aim was to identify the by-products formed. The effects of pH and the presence of bromide ions were studied. Reactions have been carried out at room temperature, in phosphate buffered aqueous solutions, at four pHs (6, 7, 8 and 9). By-products identification was first performed using relatively high initial reagent concentrations which were analytically convenient ([isoproturon] = 40 mg/l, [HClO + ClO-] = 160 mg Cl/l, [Br-] = 80 mg/l). In follow-up studies, the by-products identified during this preliminary step were searched for when using concentration values closer to those actually encountered at real water treatment plants ([isoproturon] = 0.4 and 0.004 mg/l, [HClO + ClO-] = 1.6 mg Cl/l, [Br-] = 0.8 and 0.008 mg/l). Under all of the studied conditions, the results showed that isoproturon is completely degraded and that it decays much faster in the presence of bromide. The pH has a negligible influence when bromide ions are absent. On the contrary, if bromide ions are present, the isoproturon decay is slower at higher pH values. High-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses have led to the identification of several by-products as a result of simultaneous oxidation and substitution reactions, both occurring on the aromatic ring of the herbicide. However, the more abundant by-products are those resulting from the oxidation of the isoproturon aromatic ring. As far as halogenated by-products are concerned, the higher the bromide ion concentration the higher the ratio of brominated to chlorinated by-products. On the basis of the analytical results, a pathway for isoproturon degradation under the studied conditions is proposed.

  3. The transport and behaviour of isoproturon in unsaturated chalk cores

    NASA Astrophysics Data System (ADS)

    Besien, T. J.; Williams, R. J.; Johnson, A. C.

    2000-04-01

    A batch sorption study, a microcosm degradation study, and two separate column leaching studies were used to investigate the transport and fate of isoproturon in unsaturated chalk. The column leaching studies used undisturbed core material obtained from the field by dry percussion drilling. Each column leaching study used 25 cm long, 10 cm wide unsaturated chalk cores through which a pulse of isoproturon and bromide was eluted. The cores were set-up to simulate conditions in the unsaturated zone of the UK Chalk aquifer by applying a suction of 1 kPa (0.1 m H 2O) to the base of each column, and eluting at a rate corresponding to an average recharge rate through the unsaturated Chalk. A dye tracer indicated that the flow was through the matrix under these conditions. The results from the first column study showed high recovery rates for both isoproturon (73-92%) and bromide (93-96%), and that isoproturon was retarded by a factor of about 1.23 relative to bromide. In the second column study, two of the four columns were eluted with non-sterile groundwater in place of the sterile groundwater used on all other columns, and this study showed high recovery rates for bromide (85-92%) and lower recovery rates for isoproturon (66-79% — sterile groundwater, 48-61% — non-sterile groundwater). The enhanced degradation in the columns eluted with non-sterile groundwater indicated that groundwater microorganisms had increased the degradation rate within these columns. Overall, the reduced isoproturon recovery in the second column study was attributed to increased microbial degradation as a result of the longer study duration (162 vs. 105 days). The breakthrough curves (BTCs) for bromide had a characteristic convection-dispersion shape and were accurately simulated with the minimum of calibration using a simple convection-dispersion model (LEACHP). However, the isoproturon BTCs had an unusual shape and could not be accurately simulated.

  4. Evaluating equilibrium and non-equilibrium transport of bromide and isoproturon in disturbed and undisturbed soil columns.

    PubMed

    Dousset, S; Thevenot, M; Pot, V; Simunek, J; Andreux, F

    2007-12-07

    In this study, displacement experiments of isoproturon were conducted in disturbed and undisturbed columns of a silty clay loam soil under similar rainfall intensities. Solute transport occurred under saturated conditions in the undisturbed soil and under unsaturated conditions in the sieved soil because of a greater bulk density of the compacted undisturbed soil compared to the sieved soil. The objective of this work was to determine transport characteristics of isoproturon relative to bromide tracer. Triplicate column experiments were performed with sieved (structure partially destroyed to simulate conventional tillage) and undisturbed (structure preserved) soils. Bromide experimental breakthrough curves were analyzed using convective-dispersive and dual-permeability (DP) models (HYDRUS-1D). Isoproturon breakthrough curves (BTCs) were analyzed using the DP model that considered either chemical equilibrium or non-equilibrium transport. The DP model described the bromide elution curves of the sieved soil columns well, whereas it overestimated the tailing of the bromide BTCs of the undisturbed soil columns. A higher degree of physical non-equilibrium was found in the undisturbed soil, where 56% of total water was contained in the slow-flow matrix, compared to 26% in the sieved soil. Isoproturon BTCs were best described in both sieved and undisturbed soil columns using the DP model combined with the chemical non-equilibrium. Higher degradation rates were obtained in the transport experiments than in batch studies, for both soils. This was likely caused by hysteresis in sorption of isoproturon. However, it cannot be ruled out that higher degradation rates were due, at least in part, to the adopted first-order model. Results showed that for similar rainfall intensity, physical and chemical non-equilibrium were greater in the saturated undisturbed soil than in the unsaturated sieved soil. Results also suggested faster transport of isoproturon in the undisturbed soil due to higher preferential flow and lower fraction of equilibrium sorption sites.

  5. Evaluating equilibrium and non-equilibrium transport of bromide and isoproturon in disturbed and undisturbed soil columns

    NASA Astrophysics Data System (ADS)

    Dousset, S.; Thevenot, M.; Pot, V.; Šimunek, J.; Andreux, F.

    2007-12-01

    In this study, displacement experiments of isoproturon were conducted in disturbed and undisturbed columns of a silty clay loam soil under similar rainfall intensities. Solute transport occurred under saturated conditions in the undisturbed soil and under unsaturated conditions in the sieved soil because of a greater bulk density of the compacted undisturbed soil compared to the sieved soil. The objective of this work was to determine transport characteristics of isoproturon relative to bromide tracer. Triplicate column experiments were performed with sieved (structure partially destroyed to simulate conventional tillage) and undisturbed (structure preserved) soils. Bromide experimental breakthrough curves were analyzed using convective-dispersive and dual-permeability (DP) models (HYDRUS-1D). Isoproturon breakthrough curves (BTCs) were analyzed using the DP model that considered either chemical equilibrium or non-equilibrium transport. The DP model described the bromide elution curves of the sieved soil columns well, whereas it overestimated the tailing of the bromide BTCs of the undisturbed soil columns. A higher degree of physical non-equilibrium was found in the undisturbed soil, where 56% of total water was contained in the slow-flow matrix, compared to 26% in the sieved soil. Isoproturon BTCs were best described in both sieved and undisturbed soil columns using the DP model combined with the chemical non-equilibrium. Higher degradation rates were obtained in the transport experiments than in batch studies, for both soils. This was likely caused by hysteresis in sorption of isoproturon. However, it cannot be ruled out that higher degradation rates were due, at least in part, to the adopted first-order model. Results showed that for similar rainfall intensity, physical and chemical non-equilibrium were greater in the saturated undisturbed soil than in the unsaturated sieved soil. Results also suggested faster transport of isoproturon in the undisturbed soil due to higher preferential flow and lower fraction of equilibrium sorption sites.

  6. Thermal decomposition mechanism of 1-ethyl-3-methylimidazolium bromide ionic liquid.

    PubMed

    Chambreau, Steven D; Boatz, Jerry A; Vaghjiani, Ghanshyam L; Koh, Christine; Kostko, Oleg; Golan, Amir; Leone, Stephen R

    2012-06-21

    In order to better understand the volatilization process for ionic liquids, the vapor evolved from heating the ionic liquid 1-ethyl-3-methylimidazolium bromide (EMIM(+)Br(-)) was analyzed via tunable vacuum ultraviolet photoionization time-of-flight mass spectrometry (VUV-PI-TOFMS) and thermogravimetric analysis mass spectrometry (TGA-MS). For this ionic liquid, the experimental results indicate that vaporization takes place via the evolution of alkyl bromides and alkylimidazoles, presumably through alkyl abstraction via an S(N)2 type mechanism, and that vaporization of intact ion pairs or the formation of carbenes is negligible. Activation enthalpies for the formation of the methyl and ethyl bromides were evaluated experimentally, ΔH(‡)(CH(3)Br) = 116.1 ± 6.6 kJ/mol and ΔH(‡)(CH(3)CH(2)Br) = 122.9 ± 7.2 kJ/mol, and the results are found to be in agreement with calculated values for the S(N)2 reactions. Comparisons of product photoionization efficiency (PIE) curves with literature data are in good agreement, and ab initio thermodynamics calculations are presented as further evidence for the proposed thermal decomposition mechanism. Estimates for the enthalpy of vaporization of EMIM(+)Br(-) and, by comparison, 1-butyl-3-methylimidazolium bromide (BMIM(+)Br(-)) from molecular dynamics calculations and their gas phase enthalpies of formation obtained by G4 calculations yield estimates for the ionic liquids' enthalpies of formation in the liquid phase: ΔH(vap)(298 K) (EMIM(+)Br(-)) = 168 ± 20 kJ/mol, ΔH(f, gas)(298 K) (EMIM(+)Br(-)) = 38.4 ± 10 kJ/mol, ΔH(f, liq)(298 K) (EMIM(+)Br(-)) = -130 ± 22 kJ/mol, ΔH(f, gas)(298 K) (BMIM(+)Br(-)) = -5.6 ± 10 kJ/mol, and ΔH(f, liq)(298 K) (BMIM(+)Br(-)) = -180 ± 20 kJ/mol.

  7. Evaluating of the Anticonvulsant Gabapentin against Nerve Agent-Induced Seizures in a Guinea Pig Model

    DTIC Science & Technology

    2010-07-01

    from Cutter Labs, Inc. (Berkeley, CA). Pyridostigmine bromide was obtained from Hoffmann- La Roche, Inc. (Nutley, NJ), and pyridine-2-aldoxime... Pyridostigmine bromide was prepared in sterile water to a concentration of 0.052 mg/ml. Atropine sulfate (4 mg/ml) and 2-PAM (50 mg/ml) were prepared in...activity. After a week recovery, animals were pretreated with pyridostigmine 30 min prior to subcutaneous soman challenge (56 ug/kg; 2 X LD50

  8. Sucrose tricarboxylate by sonocatalysed TEMPO-mediated oxidation.

    PubMed

    Lemoine, S; Thomazeau, C; Joannard, D; Trombotto, S; Descotes, G; Bouchu, A; Queneau, Y

    2000-06-16

    Oxidation of sucrose by the NaOCl/TEMPO system provided sucrose tricarboxylate without the addition of sodium bromide as co-catalyst when high-frequency (500 kHz) ultrasound was applied, in contrast to very limited conversion without sonication. In the presence of sodium bromide, sonication also caused acceleration of the oxidation. The rate increase due to sonication of the oxidant system prior to sucrose addition suggests that ultrasound acts at the level of the formation of the nitrosonium ion, the active oxidising species in the catalytic cycle.

  9. Metal cluster's effect on the optical properties of cesium bromide thin films

    NASA Astrophysics Data System (ADS)

    Kumar, Kuldeep; Arun, P.; Ravi Kant, Chhaya; Juluri, Bala Krishna

    2012-06-01

    Cesium bromide (CsBr) films grown on glass substrates by thermal evaporation showed prominent absorption peaks in the UV-visible region. Interestingly, these absorption spectra showed peaks which red shifted over time in ambient exposure. Structural and morphological studies suggested decrease in particle size overtime which was unusual. Electron micrographs show the formation of "daughter" cesium nanorods from parent CsBr particles. Theoretical calculations show the optical behavior observed to be due to localized surface plasmon resonance resulting from cesium nanorods.

  10. An Electrochemical Investigation of the 1-Methyl-3-Ethylimidazolium Bromide Aluminum Bromide Molten Salt System

    DTIC Science & Technology

    1991-02-01

    until no color was Although Popov and Geske (3), among others, have char- observed in the collected material (a total of 3-5 subli- acterized the...voltammetry. scan rate was extrapolated to a scan rate of zero. The re- The assignments pruposed by Popov and Geske (3) for suiting formal electrode...Popov and D. H. Geske , J. Am. Chem. Soc.. 80, 1045 (1969). 5346 (1958). 14. M. Lipsztajn and R. A. Osteryoung, Inorg. Chem., 23, 4. J. S. Wilkes, J

  11. Synthesis of isoflavones by room-temperature nickel-catalyzed cross-couplings of 3-iodo(bromo)chromones with arylzincs.

    PubMed

    Zhang, Zunting; Qiao, Jinfeng; Wang, Ding; Han, Ling; Ding, Ru

    2014-05-01

    A new concise, facile method for synthesis of isoflavones was accomplished in moderate to good yields for 3-iodochromones or 3-bromochromones and arylzinc bromides via Negishi cross-coupling reaction catalyzed by NiCl(2)/PPh(3) or NiCl(2)(PPh(3))(2) at room temperature. The Isoflavone core was synthesized in four steps in good yield, starting from commercially available 2-hydroxyacetophenone and aromatic bromide. Three steps of the procedure were carried out at room temperature.

  12. Colorimetric susceptibility testing for Aspergillus fumigatus: comparison of menadione-augmented 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide and Alamar blue tests.

    PubMed Central

    Jahn, B; Stüben, A; Bhakdi, S

    1996-01-01

    Two colorimetric methods that use Alamar Blue or 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) for assaying the in vitro activities of antifungal agents have been described. We report that both tests performed similarly when the antifungal activity of amphotericin B against Candida albicans was determined. However, only the MTT test generated interpretable data when Aspergillus fumigatus was used. PMID:8818910

  13. Bis(2,2′-bipyridyl-κ2 N,N′)(carbonato-κ2 O,O′)cobalt(III) bromide trihydrate

    PubMed Central

    Ma, Peng-Tao; Wang, Yu-Xia; Zhang, Guo-Qian; Li, Ming-Xue

    2008-01-01

    The title complex, [Co(CO3)(C10H8N2)2]Br·3H2O, is isostructural with the chloride analogue. The six-coordinated octahedral [Co(2,2′-bipy)2CO3]+ cation (2,2′-bipy is 2,2′-bipyrid­yl), bromide ion and water mol­ecules are linked together via O—H⋯Br and O—H⋯O hydrogen bonds, generating a one-dimensional chain. PMID:21200495

  14. Large-scale natural gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 2. Analysis of spatial moments for a nonreactive tracer

    USGS Publications Warehouse

    Garabedian, Stephen P.; LeBlanc, Dennis R.; Gelhar, Lynn W.; Celia, Michael A.

    1991-01-01

    A large-scale natural gradient tracer test was conducted to examine the transport of reactive and nonreactive tracers in a sand and gravel aquifer on Cape Cod, Massachusetts. As part of this test the transport of bromide, a nonreactive tracer, was monitored for about 280 m and quantified using spatial moments. The calculated mass of bromide for each sampling date varied between 85% and 105% of the injected mass using an estimated porosity of 0.39, and the center of mass moved at a nearly constant horizontal velocity of 0.42 m per day. A nonlinear change in the bromide longitudinal variance was observed during the first 26 m of travel distance, but afterward the variance followed a linear trend, indicating the longitudinal dispersivity had reached a constant value of 0.96 m. The transverse dispersivities were much smaller; transverse horizontal dispersivity was 1.8 cm, and transverse vertical dispersivity was about 1.5 mm.

  15. Aclidinium bromide plus formoterol for the treatment of chronic obstructive pulmonary disease.

    PubMed

    Lal, Chitra; Strange, Charlie

    2015-02-01

    Drugs that target dynamic hyperinflation such as long-acting β-2 agonists and long-acting antimuscarinic antagonists form a cornerstone of chronic obstructive pulmonary disease (COPD) management. The idea of combining these two medications in a single formulation, which may potentially improve patient compliance, is novel and attractive. The pharmacologic profiles of aclidinium bromide and formoterol fumarate are discussed. However, studies to define drug interactions and alterations in the pharmacodynamics and pharmacokinetics of the fixed dose combination (FDC) of aclidinium bromide/formoterol fumarate in large populations remain unpublished. Results of Phase II and two Phase III pivotal trials, ACLIFORM/COPD and AUGMENT COPD, evaluating the FDC are discussed. Initial data for the aclidinium/formoterol inhaler appears to be promising for impacting the lung function. To define if this benefit translates into improved long-term outcomes of decreased exacerbation frequency, improved quality of life and decreased disease-specific mortality are important. The introduction of this combination will likely have a significant impact on the prescribing habits of physicians across the world.

  16. Design, evaluation and recommedation effort relating to the modification of a residential 3-ton absorption cycle cooling unit for operation with solar energy

    NASA Technical Reports Server (NTRS)

    Merrick, R. H.; Anderson, P. P.

    1973-01-01

    The possible use of solar energy powered absorption units to provide cooling and heating of residential buildings is studied. Both, the ammonia-water and the water-lithium bromide cycles, are considered. It is shown that the air cooled ammonia water unit does not meet the criteria for COP and pump power on the cooling cycle and the heat obtained from it acting as a heat pump is at too low a temperature. If the ammonia machine is water cooled it will meet the design criteria for cooling but can not supply the heating needs. The water cooled lithium bromide unit meets the specified performance for cooling with appreciably lower generator temperatures and without a mechanical solution pump. It is recommeded that in the demonstration project a direct expansion lithium bromide unit be used for cooling and an auxiliary duct coil using the solar heated water be employed for heating.

  17. Pyridostigmine bromide and the long-term subjective health status of a sample of over 700 male Reserve Component Gulf War era veterans.

    PubMed

    Schumm, Walter R; Reppert, Earl J; Jurich, Anthony P; Bollman, Stephan R; Webb, Farrell J; Castelo, Carlos S; Stever, James C; Kaufman, Mark; Deng, Liang-Yu; Krehbiel, Michelle; Owens, Barbara L; Hall, Carolyn A; Brown, Beverlyn F Cay; Lash, Jeanne F; Fink, Carol J; Crow, Janet R; Bonjour, Gabriele N

    2002-06-01

    Data from a 1996-1997 survey of approximately 700 Reserve Component male veterans indicate that the consumption of pyridostigmine bromide pills, used as a pretreatment for potential exposure to the nerve agent Soman, was a significant predictor of declines in reported subjective health status after the war, even after controlling for a number of other possible factors. Reported reactions to vaccines and other medications also predicted declines in subjective health. While higher military rank generally predicted better health during and after the war, educational attainment, minority status, number of days in theater, and age generally did not predict changes in subjective health. Although servicemembers were directed to take three pills a day, veterans reported a range of compliance--less than a fourth (24%) followed the medical instructions compared to 61% who took fewer than three pills daily and 6% who took six or more pills a day. Implications for use of pyridostigmine bromide are discussed.

  18. Inorganic bromine in organic molecular crystals: Database survey and four case studies

    NASA Astrophysics Data System (ADS)

    Nemec, Vinko; Lisac, Katarina; Stilinović, Vladimir; Cinčić, Dominik

    2017-01-01

    We present a Cambridge Structural Database and experimental study of multicomponent molecular crystals containing bromine. The CSD study covers supramolecular behaviour of bromide and tribromide anions as well as halogen bonded dibromine molecules in crystal structures of organic salts and cocrystals, and a study of the geometries and complexities in polybromide anion systems. In addition, we present four case studies of organic structures with bromide, tribromide and polybromide anions as well as the neutral dibromine molecule. These include the first observed crystal with diprotonated phenazine, a double salt of phenazinium bromide and tribromide, a cocrystal of 4-methoxypyridine with the neutral dibromine molecule as a halogen bond donor, as well as bis(4-methoxypyridine)bromonium polybromide. Structural features of the four case studies are in the most part consistent with the statistically prevalent behaviour indicated by the CSD study for given bromine species, although they do exhibit some unorthodox structural features and in that indicate possible supramolecular causes for aberrations from the statistically most abundant (and presumably most favourable) geometries.

  19. Integration of Bromine and Cyanogen Bromide Generators for the Continuous-Flow Synthesis of Cyclic Guanidines.

    PubMed

    Glotz, Gabriel; Lebl, René; Dallinger, Doris; Kappe, C Oliver

    2017-10-23

    A continuous-flow process for the in situ on-demand generation of cyanogen bromide (BrCN) from bromine and potassium cyanide that makes use of membrane-separation technology is described. In order to circumvent the handling, storage, and transportation of elemental bromine, a continuous bromine generator using bromate-bromide synproportionation can optionally be attached upstream. Monitoring and quantification of BrCN generation was enabled through the implementation of in-line FTIR technology. With the Br 2 and BrCN generators connected in series, 0.2 mmol BrCN per minute was produced, which corresponds to a 0.8 m solution of BrCN in dichloromethane. The modular Br 2 /BrCN generator was employed for the synthesis of a diverse set of biologically relevant five- and six-membered cyclic amidines and guanidines. The set-up can either be operated in a fully integrated continuous format or, where reactive crystallization is beneficial, in semi-batch mode. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Fumigation of Jute Bags with Ethylene Oxide and Methyl Bromide to Eradicate Potato Ring Rot Bacteria1

    PubMed Central

    Richardson, L. T.; Monro, H. A. U.

    1962-01-01

    In a series of full-scale tests, the effectiveness of various fumigant treatments for the eradication of potato ring rot bacteria from bulk lots of contaminated jute bags was evaluated. Survival of these bacteria on infested sample fibers located at various positions within and around a tightly wired bale was determined quantitatively from the growth lag in a liquid medium as indicated by the rate of turbidity development. Ethylene oxide, though highly toxic to Corynebacterium sepedonicum in laboratory tests, failed to penetrate the jute sufficiently to be effective in the interior of a bale. Methyl bromide showed better penetration, but was not sufficiently toxic at practical dosage levels. A mixture of 5% ethylene oxide and 10% methyl bromide achieved complete eradication throughout a bale in an 18-hr exposure period. On the basis of these results, eradication of ring rot bacteria from contaminated jute bags by fumigation with a combination of these two gases would appear to be feasible under commercial conditions. PMID:13982125

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