WorldWideScience

Sample records for dysprosium bromides

  1. Dysprosium magneto-optical traps

    CERN Document Server

    Youn, Seo Ho; Ray, Ushnish; Lev, Benjamin L

    2010-01-01

    Magneto-optical traps (MOTs) of highly magnetic lanthanides open the door to explorations of novel phases of strongly correlated matter such as lattice supersolids and quantum liquid crystals. We recently reported the first MOTs of the five high abundance isotopes of the most magnetic atom, dysprosium. Described here are details of the experimental technique employed for repumper-free Dy MOTs containing up to half a billion atoms. Extensive characterization of the MOTs' properties---population, temperature, loading, metastable decay dynamics, trap dynamics---is provided.

  2. On polymorphism of dysprosium trichloride

    Energy Technology Data Exchange (ETDEWEB)

    Zakiryanova, Irina D.; Khokhlov, Vladimir A.; Salyulev, Alexander B.; Korzun, Iraida V. [RAS Ural Branch, Ekaterinburg (Russian Federation). Institute of High-Temperature Electrochemistry

    2015-07-01

    For the first time, the structure of crystalline DyCl{sub 3} over a wide temperature range from room temperature to melting point was studied by Raman spectroscopy. The phonon modes (cm{sup -1}) of dysprosium trichloride (monoclinic crystal lattice of AlCl{sub 3} type, Z = 4, CN = 6) at room temperature are 257 (A{sub 1g}), 201 (E{sub g}), 112 (E{sub g}), 88 (A{sub 1g}), and 63 (E{sub g}). The monoclinic structure of the crystalline DyCl{sub 3} C{sub 2h}{sup 3} symmetry was found to remain constant over the studied temperature range. No polymorphic transformation in the solid state was detected. Gravimetry, calorimetry, and mass spectrometry have been used in addition to support the conclusions made on the basis of Raman spectroscopic data.

  3. Resonance ionization spectroscopy in dysprosium

    Energy Technology Data Exchange (ETDEWEB)

    Studer, D., E-mail: dstuder@uni-mainz.de; Dyrauf, P.; Naubereit, P.; Heinke, R.; Wendt, K. [Johannes Gutenberg-Universität Mainz, Institut für Physik (Germany)

    2017-11-15

    We report on resonance ionization spectroscopy (RIS) of high-lying energy levels in dysprosium. We developed efficient excitation schemes and re-determined the first ionization potential (IP) via analysis of Rydberg convergences. For this purpose both two- and three-step excitation ladders were investigated. An overall ionization efficiency of 25(4) % could be demonstrated in the RISIKO mass separator of Mainz University, using a three-step resonance ionization scheme. Moreover, an extensive analysis of the even-parity 6sns- and 6snd-Rydberg-series convergences, measured via two-step excitation was performed. To account for strong perturbations in the observed s-series, the approach of multichannel quantum defect theory (MQDT) was applied. Considering all individual series limits we extracted an IP-value of 47901.76(5) cm{sup −1}, which agrees with the current literature value of 47901.7(6) cm{sup −1}, but is one order of magnitude more precise.

  4. Aclidinium Bromide

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli

    2012-01-01

    Long-acting bronchodilators are the mainstay of pharmacological treatment for patients with chronic obstructive pulmonary disease (COPD). The aim of this review is to provide an overview of the clinical studies evaluating the safety and efficacy of inhaled aclidinium bromide, a novel long...

  5. The dysprosium-tin phase diagram

    Energy Technology Data Exchange (ETDEWEB)

    Eremenko, V.N.; Bulanova, M.V.; Martsenjuk, P.S. (I.N. Frantsevich Inst. for Problems of Materials Science, Kiev (Ukraine))

    1992-12-07

    The dysprosium-tin phase diagram was established by means of differential thermal, X-ray and microscopic analyses of 22 alloys. Seven intermetallic compounds were found to exist in the system. Dy[sub 5]Sn[sub 3] melts congruently at 1870 degC, and undergoes a polymorphous transformation at 1823 [+-] 6 degC. The intermetallics Dy[sub 5]Sn[sub 4], Dy[sub 11]Sn[sub 10], DySn, Dy[sub 4]Sn[sub 5], DySn[sub 2], DySn[sub 3] are formed peritectically at 1712 [+-]11, 1605 [+-]12, 1208 [+-]3, 1166 [+-]7, 1138 [+-]3 and 747 [+-]6 degC respectively. DySn[sub 3] exists in a narrow temperature range, in two polymorphous modifications. The transformation [beta]-DySn[sub 3] [yields] [alpha]-DySn[sub 3] occurs at 608 [+-] 12 degC, and at 499 [+-]2 degC [alpha]-DySn[sub 3] decomposes to DySn[sub 2] and the tin-rich melt. The dysprosium-rich eutectic crystallizes at 1204 [+-]10 degC and contains 13 at.% tin. The solid-state solubility of tin in dysprosium is about 3 at.%, and that of dysprosium in tin is negligible.

  6. Towards a new measurement of parity violation in dysprosium

    CERN Document Server

    Leefer, N; Antypas, D; Budker, D

    2014-01-01

    The dysprosium parity violation experiment concluded nearly 17 years ago with an upper limit on weak interaction induced mixing of nearly degenerate, opposite parity states in atomic dysprosium. While that experiment was limited in sensitivity by statistics, a new apparatus constructed in the interim for radio-frequency spectroscopy is expected to provide significant improvements to the statistical sensitivity. Preliminary work from the new PV experiment in dysprosium is presented with a discussion of the current statistical sensitivity and outlook.

  7. Dysprosium Modification of Cobalt Ferrite Ionic Magnetic Fluids

    Institute of Scientific and Technical Information of China (English)

    JIANG Rong-li; LIU Yong-chao; GENG Quan-rong; ZHAO Wen-tao

    2005-01-01

    Dysprosium composite cobalt ferrite ionic magnetic fluids were prepared by precipitation in the presence of Tri-sodium citrate. Influence of dysprosium modification on magnetic property is studied. The result shows that magnetic response toward exterior magnetic field can be improved by adding Dy3+. Studies also show that the increase of reaction temperature may improve the modification effect of dysprosium. By adding dysprosium ions, the average diameter of the magnetic nanoparticles will be decreased evidently. It is clear that the particles appear as balls, Cobalt ferrite with sizes of 12-15 nm, rare earth composite cobalt ferrite with sizes of 6-8 nm.

  8. Can a dysprosium shortage threaten green energy technologies?

    NARCIS (Netherlands)

    Hoenderdaal, S.; Tercero Espinoza, L.; Marschneider-Weidemann, F.; Crijns - Graus, Wina

    2013-01-01

    Dysprosium, one of the various rare earth elements, is currently for more than 99% mined in China. As China is reducing its exports, new mining projects outside of China are needed to sustain supply and meet future demands. Dysprosium is mainly used in permanent magnets to retain the magnet's streng

  9. Phenalenyl-based mononuclear dysprosium complexes

    Directory of Open Access Journals (Sweden)

    Yanhua Lan

    2016-07-01

    Full Text Available The phenalenyl-based dysprosium complexes [Dy(PLN2(HPLNCl(EtOH] (1, [Dy(PLN3(HPLN]·[Dy(PLN3(EtOH]·2EtOH (2 and [Dy(PLN3(H2O2]·H2O (3, HPLN being 9-hydroxy-1H-phenalen-1-one, have been synthesized. All compounds were fully characterized by means of single crystal X-ray analysis, paramagnetic 1H NMR, MALDI-TOF mass spectrometry, UV–vis spectrophotometry and magnetic measurements. Both static (dc and dynamic (ac magnetic properties of these complexes have been investigated, showing slow relaxation of magnetization, indicative of single molecule magnet (SMM behavior. Attempts to synthesize sublimable phenalenyl-based dysprosium complexes have been made by implementing a synthetic strategy under anhydrous conditions. The sublimed species were characterized and their thermal stability was confirmed. This opens up the possibility to deposit phenalenyl-based lanthanides complexes by sublimation onto surfaces, an important prerequisite for ongoing studies in molecular spintronics.

  10. Anisotropy in the Interaction of Ultracold Dysprosium

    CERN Document Server

    Kotochigova, Svetlana

    2011-01-01

    The nature of the interaction between ultracold atoms with a large orbital and spin angular momentum has attracted considerable attention. It was suggested that such interactions can lead to the realization of exotic states of highly correlated matter. Here, we report on a theoretical study of the competing anisotropic dispersion, magnetic dipole-dipole, and electric quadrupole-quadrupole forces between two dysprosium atoms. Each dysprosium atom has an orbital angular momentum L=6 and magnetic moment $\\mu=10\\mu_B$. We show that the dispersion coefficients of the ground state adiabatic potentials lie between 1865 a.u. and 1890 a.u., creating a non-negligible anisotropy with a spread of 25 a.u. and that the electric quadrupole-quadrupole interaction is weak compared to the other interactions. We also find that for interatomic separations $R< 50\\,a_0$ both the anisotropic dispersion and magnetic dipole-dipole potential are larger than the atomic Zeeman splittings for external magnetic fields of order 10 G to ...

  11. First search for double $\\beta$ decay of dysprosium

    CERN Document Server

    Belli, P; Cappella, F; Cerulli, R; Danevich, F A; d'Angelo, S; Di Vacri, M L; Incicchitti, A; Laubenstein, M; Nagorny, S S; Nisi, S; Tolmachev, A V; Tretyak, V I; Yavetskiy, R P

    2011-01-01

    A search for double $\\beta$ decay of dysprosium was realized for the first time with the help of an ultra low-background HP Ge $\\gamma$ detector. After 2512 h of data taking with a 322 g sample of dysprosium oxide limits on double beta processes in $^{156}$Dy and $^{158}$Dy have been established on the level of $T_{1/2}\\geq 10^{14}-10^{16}$ yr. Possible resonant double electron captures in $^{156}$Dy and $^{158}$Dy were restricted on a similar level. As a by-product of the experiment we have measured the radioactive contamination of the Dy$_2$O$_3$ sample and set limits on the $\\alpha$ decay of dysprosium isotopes to the excited levels of daughter nuclei as $T_{1/2}\\geq 10^{15} - 10^{17}$ yr.

  12. Neutron resonance parameters of dysprosium isotopes using neutron capture yields

    Energy Technology Data Exchange (ETDEWEB)

    Shin, S. G.; Kye, Y. U.; Cho, M. H. [POSTECH, Pohang (Korea, Republic of); Namkung, W. [Pohang Accelerator Laboratory, Pohang (Korea, Republic of); Kim, G. N. [Kyungpook National University, Daegu (Korea, Republic of); Lee, M. W.; Kang, Y. R. [Dongnam Inst. Of Radiological and Medical Science, Busan (Korea, Republic of)

    2015-10-15

    Dysprosium is used in the field of nuclear reactor system because it has a very large thermal neutron absorption cross-section. The dysprosium alloyed with special stainless steels is attractive for control in nuclear reactor because of the ability to absorb neutrons readily without swelling or contracting over time and its high melting point. Dysprosium is also one of fission products from the thermal fission of {sup 234}U, {sup 233}U, and {sup 239}Pu. The fission products are accumulated in the reactor core by the burn-up of the nuclear fuel and the poison effect is increased. Therefore, it is required to understand how Dysprosium as both a poison and an absorbing material in the control rod has an effect on the neutron population in a nuclear reactor system over all energy regions. Neutron Capture experiments on Dy isotopes were performed at the electron linear accelerator (LINAC) facility of the Rensselear Polytechnic Institute (RPI) in the neutron energy region from 10 eV to 1 keV. Resonance parameters were extracted by fitting the neutron capture data using the SAMMY multilevel R-matrix Bayesian code.

  13. Properties of Polydisperse Tin-doped Dysprosium and Indium Oxides

    Directory of Open Access Journals (Sweden)

    Malinovskaya Tatyana

    2017-01-01

    Full Text Available The results of investigations of the complex permittivity, diffuse-reflectance, and characteristics of crystal lattices of tin-doped indium and dysprosium oxides are presented. Using the methods of spectroscopy and X-ray diffraction analysis, it is shown that doping of indium oxide with tin results in a significant increase of the components of the indium oxide complex permittivity and an appearance of the plasma resonance in its diffuse-reflectance spectra. This indicates the appearance of charge carriers with the concentration of more than 1021 cm−3 in the materials. On the other hand, doping of the dysprosium oxide with the same amount of tin has no effect on its optical and electromagnetic properties.

  14. Dysprosium titanate as an absorber material for control rods

    Science.gov (United States)

    Risovany, V. D.; Varlashova, E. E.; Suslov, D. N.

    2000-09-01

    Disprosium titanate is an attractive control rod material for the thermal neutron reactors. Its main advantages are: insignificant swelling, no out-gassing under neutron irradiation, rather high neutron efficiency, a high melting point (˜1870°C), non-interaction with the cladding at temperatures above 1000°C, simple fabrication and easily reprocessed non-radioactive waste. It can be used in control rods as pellets and powder. The disprosium titanate control rods have worked off in the MIR reactor for 17 years, in VVER-1000 - for 4 years without any operating problems. After post-irradiation examinations this type of control rod having high lifetime was recommended for the VVER and RBMK. The paper presents the examination results of absorber element dummies containing dysprosium titanate, irradiated in the SM reactor to the neutron fluence of 3.4×10 22 cm -2 ( E>0.1 MeV) and, also, the data on structure, thermal-physical properties of dysprosium titanate, efficiency of dysprosium titanate control rods.

  15. Dysprosium electrodeposition from a hexaalkylguanidinium-based ionic liquid

    Science.gov (United States)

    Berger, Claudia A.; Arkhipova, Maria; Maas, Gerhard; Jacob, Timo

    2016-07-01

    The rare-earth element dysprosium (Dy) is an important additive that increases the magnetocrystalline anisotropy of neodymium magnets and additionally prevents from demagnetizing at high temperatures. Therefore, it is one of the most important elements for high-tech industries and is mainly used in permanent magnetic applications, for example in electric vehicles, industrial motors and direct-drive wind turbines. In an effort to develop a more efficient electrochemical technique for depositing Dy on Nd-magnets in contrast to commonly used costly physical vapor deposition, we investigated the electrochemical behavior of dysprosium(iii) trifluoromethanesulfonate in a custom-made guanidinium-based room-temperature ionic liquid (RTIL). We first examined the electrodeposition of Dy on an Au(111) model electrode. The investigation was carried out by means of cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS). The initial stages of metal deposition were followed by in situ scanning tunneling microscopy (STM). CV measurements revealed a large cathodic reduction peak, which corresponds to the growth of monoatomic high islands, based on STM images taken during the initial stages of deposition. XPS identified these deposited islands as dysprosium. A similar reduction peak was also observed on an Nd-Fe-B substrate, and positively identified as deposited Dy using XPS. Finally, we varied the concentration of the Dy precursor, electrolyte flow and temperature during Dy deposition and demonstrated that each of these parameters could be used to increase the thickness of the Dy deposit, suggesting that these parameters could be tuned simultaneously in a temperature-controlled flow cell to enhance the thickness of the Dy layer.The rare-earth element dysprosium (Dy) is an important additive that increases the magnetocrystalline anisotropy of neodymium magnets and additionally prevents from demagnetizing at high temperatures. Therefore, it is one of the most important

  16. Rapacuronium bromide (Organon Teknika).

    Science.gov (United States)

    Plowman, A N

    1999-07-01

    Organon Teknika's rapacuronium bromide (Org-9487), the 16-N-allyl, 17-beta-propionate analog of vecuronium bromide, is in phase III clinical trials in the US and Europe for potential use as an anesthetic. It is a steroidal neuromuscular blocking drug characterized by low potency, rapid rate of block development and short time course of neuromuscular blocking action as compared with other non-depolarizing compounds [170210,221422]. A multicenter, randomized, assessor-blind, placebo-controlled, dose-finding study in patients undergoing tracheal intubation showed that the drug produced a dose dependent neuromuscular block. Doses of 1.5 to 2 mg/kg allowed rapid intubation and short duration of action [273336]. Another study showed that the drug does not cause cardiovascular side-effects [273336]. A meeting was held in Europe on 8 February 1999 to brief company employees on the registration and release of rapacuronium [319211] for which the company anticipates a launch in late 1999 [320706]. Organon estimates that the market value of Org-9487 is between dollar 100 m and dollar 250 m a year, each for Europe and the US [221422].

  17. Methylnaltrexone bromide methanol monosolvate

    Directory of Open Access Journals (Sweden)

    Xinbo Zhou

    2012-03-01

    Full Text Available In the title compound [systematic name: (4R,4aS,7aR,12bS-3-cyclopropylmethyl-4a,9-hydroxy-7-oxo-2,3,4,4a,5,6,7,7a-octahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinolin-3-ium bromide methanol monosolvate], C21H26NO4+·Br−·CH3OH, two of the three six-membered rings adopt chair conformations while the third, which contains a C=C double bond, adopts an approximate half-boat conformation. The 2,3-dihydrofuran ring adopts an envelope conformation. In the crystal, the components are linked by O—H...O and O—H...Br hydrogen bonds. The absolute stereochemistry was inferred from one of the starting materials.

  18. Iron bromide vapor laser

    Science.gov (United States)

    Sukhanov, V. B.; Shiyanov, D. V.; Trigub, M. V.; Dimaki, V. A.; Evtushenko, G. S.

    2016-03-01

    We have studied the characteristics of a pulsed gas-discharge laser on iron bromide vapor generating radiation with a wavelength of 452.9 nm at a pulse repetition frequency (PRF) of 5-30 kHz. The maximum output power amounted to 10 mW at a PRF within 5-15 kHz for a voltage of 20-25 kV applied to electrodes of the discharge tube. Addition of HBr to the medium produced leveling of the radial profile of emission. Initial weak lasing at a wavelength of 868.9 nm was observed for the first time, which ceased with buildup of the main 452.9-nm line.

  19. Dysprosium detector for neutron dosimetry in external beam radiotherapy

    Science.gov (United States)

    Ostinelli, A.; Berlusconi, C.; Conti, V.; Duchini, M.; Gelosa, S.; Guallini, F.; Vallazza, E.; Prest, M.

    2014-09-01

    Radiotherapy treatments with high-energy (>8 MeV) photon beams are a standard procedure in clinical practice, given the skin and near-target volumes sparing effect, the accurate penetration and the uniform spatial dose distribution. On the other hand, despite these advantages, neutrons may be produced via the photo-nuclear (γ,n) reactions of the high-energy photons with the high-Z materials in the accelerator head, in the treatment room and in the patient, resulting in an unwanted dose contribution which is of concern, given its potential to induce secondary cancers, and which has to be monitored. This work presents the design and the test of a portable Dysprosium dosimeter to be used during clinical treatments to estimate the "in vivo" dose to the patient. The dosimeter has been characterized and validated with tissue-equivalent phantom studies with a Varian Clinical iX 18 MV photon beam, before using it with a group of patients treated at the S. Anna Hospital in Como. The working principle of the dosimeter together with the readout chain and the results in terms of delivered dose are presented.

  20. Dysprosium detector for neutron dosimetry in external beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Ostinelli, A.; Berlusconi, C.; Conti, V.; Duchini, M.; Gelosa, S. [Medical Physics - Sant' Anna Hospital, Como (Italy); Guallini, F. [EL.SE s.r.l. (Italy); Vallazza, E. [INFN, Trieste (Italy); Prest, M. [University of Insubria, Como (Italy)

    2014-09-21

    Radiotherapy treatments with high-energy (>8MeV) photon beams are a standard procedure in clinical practice, given the skin and near-target volumes sparing effect, the accurate penetration and the uniform spatial dose distribution. On the other hand, despite these advantages, neutrons may be produced via the photo-nuclear (γ,n) reactions of the high-energy photons with the high-Z materials in the accelerator head, in the treatment room and in the patient, resulting in an unwanted dose contribution which is of concern, given its potential to induce secondary cancers, and which has to be monitored. This work presents the design and the test of a portable Dysprosium dosimeter to be used during clinical treatments to estimate the “in vivo” dose to the patient. The dosimeter has been characterized and validated with tissue-equivalent phantom studies with a Varian Clinical iX 18 MV photon beam, before using it with a group of patients treated at the S. Anna Hospital in Como. The working principle of the dosimeter together with the readout chain and the results in terms of delivered dose are presented.

  1. Low Field Magnetic and Thermal Hysteresis in Antiferromagnetic Dysprosium

    Directory of Open Access Journals (Sweden)

    Iuliia Liubimova

    2017-06-01

    Full Text Available Magnetic and thermal hysteresis (difference in magnetic properties on cooling and heating have been studied in polycrystalline Dy (dysprosium between 80 and 250 K using measurements of the reversible Villari effect and alternating current (AC susceptibility. We argue that measurement of the reversible Villari effect in the antiferromagnetic phase is a more sensitive method to detect magnetic hysteresis than the registration of conventional B(H loops. We found that the Villari point, recently reported in the antiferromagnetic phase of Dy at 166 K, controls the essential features of magnetic hysteresis and AC susceptibility on heating from the ferromagnetic state: (i thermal hysteresis in AC susceptibility and in the reversible Villari effect disappears abruptly at the temperature of the Villari point; (ii the imaginary part of AC susceptibility is strongly frequency dependent, but only up to the temperature of the Villari point; (iii the imaginary part of the susceptibility drops sharply also at the Villari point. We attribute these effects observed at the Villari point to the disappearance of the residual ferromagnetic phase. The strong influence of the Villari point on several magnetic properties allows this temperature to be ranked almost as important as the Curie and Néel temperatures in Dy and likely also for other rare earth elements and their alloys.

  2. A Low-Symmetry Dysprosium Metallocene Single-Molecule Magnet with a High Anisotropy Barrier.

    Science.gov (United States)

    Pugh, Thomas; Chilton, Nicholas F; Layfield, Richard A

    2016-09-05

    The single-molecule magnet (SMM) properties of the isocarbonyl-ligated dysprosium metallocene [Cp*2 Dy{μ-(OC)2 FeCp}]2 (1Dy ), which contains a rhombus-shaped Dy2 Fe2 core, are described. Combining a strong axial [Cp*](-) ligand field with a weak equatorial field consisting of the isocarbonyl ligands leads to an anisotropy barrier of 662 cm(-1) in zero applied field. The dominant thermal relaxation pathways in 1Dy involves at least the fourth-excited Kramers doublet, thus demonstrating that prominent SMM behavior can be observed for dysprosium in low-symmetry environments.

  3. Malonate complexes of dysprosium: synthesis, characterization and application for LI-MOCVD of dysprosium containing thin films.

    Science.gov (United States)

    Milanov, Andrian P; Seidel, Rüdiger W; Barreca, Davide; Gasparotto, Alberto; Winter, Manuela; Feydt, Jürgen; Irsen, Stephan; Becker, Hans-Werner; Devi, Anjana

    2011-01-07

    A series of malonate complexes of dysprosium were synthesized as potential metalorganic precursors for Dy containing oxide thin films using chemical vapor deposition (CVD) related techniques. The steric bulkiness of the dialkylmalonato ligand employed was systematically varied and its influence on the resulting structural and physico-chemical properties that is relevant for MOCVD was studied. Single crystal X-ray diffraction analysis revealed that the five homoleptic tris-malonato Dy complexes (1-5) are dimers with distorted square-face bicapped trigonal-prismatic geometry and a coordination number of eight. In an attempt to decrease the nuclearity and increase the solubility of the complexes in various solvents, the focus was to react these dimeric complexes with Lewis bases such as 2,2'-biypridyl and pyridine (6-9). This resulted in monomeric tris-malonato mono Lewis base adduct complexes with improved thermal properties. Finally considering the ease of synthesis, the monomeric nature and promising thermal characteristics, the silymalonate adduct complex [Dy(dsml)(3)bipy] (8) was selected as single source precursor for growing DySi(x)O(y) thin films by liquid injection metalorganic chemical vapor deposition (LI-MOCVD) process. The as-deposited films were analyzed for their morphology and composition by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, Rutherford backscattering (RBS) analysis and X-ray photoelectron spectroscopy.

  4. Exploration of dysprosium: the most critical element for Japan

    Science.gov (United States)

    Watanabe, Y.

    2012-04-01

    Dysprosium (Dy), one of the heavy rare earth elements, is used mainly as an additive for NdFeB permanent magnets which are installed in various modern industrial products such as voice coil motors in computers, factory automation machinery, hybrid and electric vehicles, home electronics, and wind turbine, to improve heat resistance of the magnets. Dy has been produced about 2,000t per year from the ores from ion adsorption type deposits in southern China. However, the produced amount of Dy was significantly reduced in 2011 in China due to reservation of heavy rare earth resources and protection of natural environment, resulting in soaring of Dy price in the world. In order to respond the increasing demand of Dy, unconventional supply sources are inevitably developed, in addition to heavy rare earth enriched ion adsorption type deposits outside China. Heavy rare earth elements including Dy are dominantly hosted in xenotime, fergusonite, zircon, eudialyte, keiviite, kainosite, iimoriite, etc. Concentration of xenotime is found in placer deposits in Malaysia and India, hydrothermal deposits associated with unconformity-type uranium mineralization (Athabasca basin in Canada, Western Australia), iron-oxide fluorite mineralization (South Africa) and Sn-bearing alkaline granite (Brazil). Zircon and fergusontie concentration is found as igneous and hydrothermal products in peralkaline syenite, alkaline granite and pegmatite (e.g., Nechalacho in Canada). Eudialyte concentration is found in some peralkaline syenite bodies in Greenland, Canada, Sweden and Russia. Among these sources, large Dy resources are estimated in the deposits hosted in peralkaline rocks (Nechalacho: 79,000t, Kvanefjeld: 49,000t, Norra Karr: 15,700t, etc.) compared to the present demand of Dy. Thus, Dy will be supplied from the deposits associated with peralkaline and alkaline deposits in future instead of ion adsorption type deposits in southern China.

  5. Long afterglow of trivalent dysprosium doped strontium aluminate

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yuan Ming, E-mail: dongshanisland@126.com [School of Mathematics and Physics, Changzhou University, Jiangsu 213164 (China); Ma, Qing-lan [School of Mathematics and Physics, Changzhou University, Jiangsu 213164 (China); School of Electronics and Information, Nantong University, Jiangsu 226019 (China)

    2015-04-15

    Trivalent dysprosium doped strontium aluminate (SrA1{sub 2}O{sub 4}:Dy{sup 3+}) was synthesized via the sol–gel combustion method to realize green afterglow in the absence of Eu{sup 2+} luminescent centers. The morphology, crystal structure, photoluminescence and long afterglow of the SrAl{sub 2}O{sub 4}:Dy{sup 3+} were characterized with scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and photoluminescence spectroscopy, respectively. The bluish-green photoluminescence of SrAl{sub 2}O{sub 4}:Dy{sup 3+} consists of a broad emission band centered at about 520 nm and two characteristic emissions of Dy{sup 3+} ions centered at 480 and 575 nm, respectively. The green afterglow of SrAl{sub 2}O{sub 4}:Dy{sup 3+} is a broad emission band centered at around 520 nm, and the lifetime extracted from afterglow decay is found to be 53 s. The mechanism on the green afterglow from SrAl{sub 2}O{sub 4}:Dy{sup 3+} is discussed in terms of the possible defect levels in the host. - Highlights: • Broad band long-lasting afterglow is observed in SrAl{sub 2}O{sub 4}:Dy{sup 3+} phosphors. • Characteristic emissions of Dy{sup 3+} ions are superimposed on the broad PL of phosphors. • Dy{sup 3+} ions can also act as luminescent centers in addition to electron traps. • A mechanism on long afterglow of SrAl{sub 2}O{sub 4}:Dy{sup 3+} is proposed without Eu{sup 2+} activator.

  6. Low temperature spin reorientation in dysprosium iron garnet

    Energy Technology Data Exchange (ETDEWEB)

    Lahoubi, M; Younsi, W; Soltani, M L [Department of Physics, Badji-Mokhtar University, BP-12 Annaba, 23000 (Algeria); Voiron, J; Schmitt, D, E-mail: mlahoubi@gmail.co [Louis Neel Laboratory, CNRS-UJF, BP-166, 38042 Grenoble Cedex 9 (France)

    2009-03-01

    The spin reorientation (SR) phase transition in dysprosium iron garnet (Dy{sub 3}Fe{sub 5}O{sub 12} or DyIG) have been studied by specific heat C{sub p}(T) and high field magnetisation measurements M{sub T}(H) and M{sub H}(T) on single crystals at low temperature. A first order SR is observed with a sharp jump at T{sub SR} = 14.5+-0.5 K in the C{sub p}(T) curve which corresponds to a spontaneous change from the high temperature (HT) easy direction (111) to an (uuw) angular low temperature (LT) phases. Above T{sub SR}, the magnetic structure is described by the irreducible representation (IR) A{sub 2g} of the rhombohedral space group R 3 c. Below T{sub SR}, the magnetic structure changes in the monoclinic the space group C2/c with the IR A{sub g}. When the field H is kept aligned along the hard symmetry directions (100) and (110), we obtain respectively the variation of the angular positions theta(T) and theta'(T) from the total spontaneous magnetisation down to 1.5 K (theta = 39.23 deg. and theta' = 30.14 deg.) and the results are in good agreement with the previous observations in low fields. When the sample is allowed to rotate freely on itself, the critical field H{sub c}(T) between the HT(111) and the LT(uuw) angular phases permits us to precise the transition line up to 15 T and 40 K between the so called canted field induced (FI) and the associated collinear magnetic phases. The experimental magnetic phase diagram (MPD) is precisely determined in the (H{sub c}-T) plane and the domains of the existence and the stability of the two magnetic phases are specified.

  7. Anisotropic magnetic properties of dysprosium iron garnet (DyIG)

    Energy Technology Data Exchange (ETDEWEB)

    Lahoubi, M; Younsi, W; Soltani, M-L [Department of Physics, Badji-Mokhtar University, BP 12 - 23000 Annaba (Algeria); Ouladdiaf, B, E-mail: mlahoubi@gmail.co [Institut Laue Langevin, BP 156 - 38042 Grenoble Cedex 9 (France)

    2010-01-01

    The magnetic properties of dysprosium iron garnet (DyIG) have been studied by performing high resolution powder neutron diffraction experiments and high dc fields magnetizations on single crystals. Among all the reflections (hkl) indexed in the nuclear cubic space group (CSG) Ia 3-bar d with h+k+l=2n and k=[000], the superstructure lines (hkl)* forbidden by the symmetry (222)* and (622)* are not observed in the patterns at all temperatures. The pattern at 130 K is well interpreted within the magnetic modes F belonging to the irreducible representation (IR) T{sub 1g} of the CSG and identified to the room temperature ferrimagnetic Neel model. The high magnetic field behavior of the spontaneous collinear magnetic structure (MS) along the easy axis (EA) <111> is isotropic. Below 130 K, the patterns exhibit additional magnetic superstructure lines. They are associated to the appearance of the spontaneous non collinear MS which is described in the subgroup of the CSG, R 3-bar c within the IR A{sub 2g}. A strong magnetization anisotropy (MA) is observed at 1.5 K in the low symmetry phases were the spin reorientation transition (SR) occur at T{sub RS}=14.5 K. The onset of MA is detected below two characteristic temperatures, Ta{sub 1}=125 K and Ta{sub 2}=75 K respectively to the hard axis (HA) <100> and <110>. Symmetry arguments are used in the framework of the theory of representation analysis (RA) applied to the subgroup of R 3-bar c, C2/c within the IR A{sub g}. It seems that this MA results essentially from the difference between the spontaneous non collinear MS and the field induced (FI) configurations. All results are discussed with previous neutrons studies.

  8. Dysprosium-containing layered double hydroxides nanoparticles intercalated with biologically active species as an approach for theranostic systems

    KAUST Repository

    Arratia-Quijada, Jenny

    2015-10-23

    A layered double hydroxide structure including dysprosium cations was prepared by co-precipitation. The nanoparticles showed a linear relationship with the reciprocal relaxation spin-lattice (T1) time of water protons which is reflected as contrast in aqueous suspensions analyzed by magnetic resonance imaging. The interlayer space of dysprosium containing LDH was successfully intercalated with folate, ibuprofen and gallate ions, which are key molecules for recognition of some cancer cells and treatment of diseases. The paramagnetic property of the dysprosium-containing LDH detected in this work beside the ability to transport drugs open up the opportunity to design theranostic materials in a single crystal phase with nanometric dimensions.

  9. Effects of Dysprosium Oxide Doping on Microstructure and Properties of Barium Titanate Ceramic

    Institute of Scientific and Technical Information of China (English)

    Pu Yongping; Ren Huijun; Chen Wei; Chen Shoutian

    2005-01-01

    Different amounts of dysprosium oxide were incorporated into barium titanate powders synthesized by hydrothermal method. Relations of substitution behaviors and lattice parameters with solid-solubility were studied. Furthermore, the influences of dysprosium oxide doping fraction on grain size and dielectric properties of barium titanate ceramic, including dielectric constant and breakdown electric field strength, were investigated via scanning electron microscope, X-ray diffraction and electric property tester. The results show that dysprosium oxide can restrain abnormal grain growth during sintering and that fine-grained and high density of barium titanate ceramic can result in excellent dielectric properties. As mass fraction of dysprosium oxide is 0.6%, the lattice parameters of grain increase to the maximum because of the lowest vacancy concentration. The electric property parameters are cited as following: dielectric constant (25 ℃) reaches 4100, the change in relative dielectric constant with temperature is -10% to 10% within the range of -15~100 ℃, breakdown electric field strength (alternating current) achieves 3.2 kV·mm-1, which can be used in manufacturing high voltage ceramic capacitors.

  10. Sandwich-type tetrakis(phthalocyaninato) dysprosium-cadmium quadruple-decker SMM.

    Science.gov (United States)

    Wang, Hailong; Qian, Kang; Wang, Kang; Bian, Yongzhong; Jiang, Jianzhuang; Gao, Song

    2011-09-14

    Homoleptic tetrakis[2,3,9,10,16,17,23,24-octa(butyloxy)phthalocyaninato] dysprosium-cadmium quadruple-decker complex 1 was isolated in relatively good yield of 43% from a simple one-pot reaction. This compound represents the first sandwich-type tetrakis(phthalocyaninato) rare earth-cadmium quadruple-decker SMM that has been structurally characterized.

  11. In situ characterization of the nitridation of dysprosium during mechanochemical processing

    Energy Technology Data Exchange (ETDEWEB)

    Jaques, Brian J.; Osterberg, Daniel D.; Alanko, Gordon A.; Tamrakar, Sumit; Smith, Cole R.; Hurley, Michael F.; Butt, Darryl P., E-mail: DarrylButt@BoiseState.edu

    2015-01-15

    Highlights: • A nitridation reaction in a high energy planetary ball mill was monitored in situ. • Dysprosium mononitride was synthesized from Dy at low temperatures in short times. • Ideal gas law and in situ temperature and pressure used to assess reaction extent. • It is proposed that reaction rate is proportional to the creation of new surface. - Abstract: Processing of advanced nitride ceramics traditionally requires long durations at high temperatures and, in some cases, in hazardous atmospheres. In this study, dysprosium mononitride (DyN) was rapidly formed from elemental dysprosium in a closed system at ambient temperatures. An experimental procedure was developed to quantify the progress of the nitridation reaction during mechanochemical processing in a high energy planetary ball mill (HEBM) as a function of milling time and intensity using in situ temperature and pressure measurements, SEM, XRD, and particle size analysis. No intermediate phases were formed. It was found that the creation of fresh dysprosium surfaces dictates the rate of the nitridation reaction, which is a function of milling intensity and the number of milling media. These results show clearly that high purity nitrides can be synthesized with short processing times at low temperatures in a closed system requiring a relatively small processing footprint.

  12. Bromide in some coastal and oceanic waters of India

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, F.P.; Dalal, V.N.K.

    Bromide concentration and bromide/chlorinity ratio are estimated in coastal waters of Goa, Minicoy Lagoon, Western Arabian Sea and Western Bay of Bengal. The influence of precipitation and river runoff on bromide and bromide/chlorinity ratio...

  13. Dysprosium complexes with the tetraphenylporphyrin macrocyclic ligand; Complejos de disprosio con el ligante macrociclico tetrafenilporfirina

    Energy Technology Data Exchange (ETDEWEB)

    Martinez M, V.; Padilla, J.; Ramirez, F.M

    1992-04-15

    In this report, the results obtained on the synthesis, characterization and study of the chemical behavior of dysprosium complex with the acetylacetone chelating agent (Hacac) and the tetraphenylporphyrin macrocyclic ligand (H{sub 2}TFP) are given. Based on the literature but according to our necessities and interest, the appropriate methodology settled down from the synthesis of prime matters until the obtaining and characterization of the products. The acetyl acetonate complex was obtained of mono hydrated dysprosium [Dy(acac){sub 3}. H{sub 2}0] and trihydrated [Dy(acac){sub 3} .3 H{sub 2}0], the mono tetra phenyl porphyrinate [Dy(TFP)(acac). 2 ac] the double sandwich of the dysprosium porphyrinate [Dy(TFP){sub 2}] and the triple sandwich of the dysprosium porphyrinate [Dy(TFP){sub 3}. 2 TCB] (TCB = trichlorobenzene). Its were characterized by their melting points, solubility, IR, UV, TGA and DTA both first and besides the techniques already mentioned for NMR'H, RPE and Magnetic susceptibility the three last complexes. From the spectroscopic point of view, IR and RPE its suggested the existence of a complex of inverse mixed valence [Dy(TFP){sup 2-} (TFP) {sup 1-}] for the Dy(TFP){sub 2} as a result of the existence of the free radical (TFP' {sup 1-} and that it was not in none of the other porphyrin compounds. In the NMR'H spectra of the compounds were not observed signals in the region from 0 to 10 ppm that which shows that the dysprosium complexes in special those of the porphyrin type are highly paramagnetic and its could be used as displacement reagents, creators of images and contrast agents of great utility in these days in studies of NMR, technique today by today used in medical diagnoses. (Author)

  14. Synthesis, structural characterization and in vitro testing of dysprosium containing silica particles as potential MRI contrast enhancing agents

    Science.gov (United States)

    Chiriac, L. B.; Trandafir, D. L.; Turcu, R. V. F.; Todea, M.; Simon, S.

    2016-11-01

    The work is focused on synthesis and structural characterization of novel dysprosium-doped silica particles which could be considered as MRI contrast agents. Sol-gel derived silica rich particles obtained via freeze-drying and spray-drying processing methods were structurally characterized by XRD, 29Si MAS-NMR and XPS methods. The occurrence of dysprosium on the outermost layer of dysprosium containing silica particles was investigated by XPS analysis. The MRI contrast agent characteristics have been tested using RARE-T1 and RARE-T2 protocols. The contrast of MRI images delivered by the investigated samples was correlated with their local structure. Dysprosium disposal on microparticles with surface structure characterised by decreased connectivity of the silicate network units favours dark T2-weighted MRI contrast properties.

  15. Dysprosium-containing layered double hydroxides nanoparticles intercalated with biologically active species as an approach for theranostic systems

    Energy Technology Data Exchange (ETDEWEB)

    Arratia-Quijada, Jenny [Departamento de Ciencias de la Salud, Centro Universitario Tonalá, Universidad de Guadalajara, Av. Nuevo Periférico No. 555, C.P. 48525, Tonalá, Jalisco (Mexico); Sánchez Jiménez, Cecilia [Departamento de Química, Universidad de Guadalajara, Boulevard Marcelino García Barragán 1421, C.P. 44430, Guadalajara, Jalisco (Mexico); Gurinov, Andrey [Research Resources Center for Magnetic Resonance, St. Petersburg State University, Universitetskiy pr. 26, 198504 St. Petersburg (Russian Federation); NMR Core Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia); Pérez Centeno, Armando; Ceja Andrade, Israel [Departamento de Física, Universidad de Guadalajara, Boulevard Marcelino García Barragán 1421, C.P. 44430, Guadalajara, Jalisco (Mexico); Carbajal Arízaga, Gregorio Guadalupe, E-mail: gregoriocarbajal@yahoo.com.mx [Departamento de Química, Universidad de Guadalajara, Boulevard Marcelino García Barragán 1421, C.P. 44430, Guadalajara, Jalisco (Mexico)

    2016-01-15

    Graphical abstract: - Highlights: • LDH structure including dysprosium was prepared by co-precipitation. • LDH was capable to produce contrast in the T1 mode of MRI. • LDH were intercalated with folate, ibuprofen and gallate ions. - Abstract: A layered double hydroxide structure including dysprosium cations was prepared by co-precipitation. The nanoparticles showed a linear relationship with the reciprocal relaxation spin-lattice (T1) time of water protons which is reflected as contrast in aqueous suspensions analyzed by magnetic resonance imaging. The interlayer space of dysprosium containing LDH was successfully intercalated with folate, ibuprofen and gallate ions, which are key molecules for recognition of some cancer cells and treatment of diseases. The paramagnetic property of the dysprosium-containing LDH detected in this work beside the ability to transport drugs open up the opportunity to design theranostic materials in a single crystal phase with nanometric dimensions.

  16. Slow magnetic relaxation in a hydrogen-bonded 2D array of mononuclear dysprosium(III) oxamates.

    Science.gov (United States)

    Fortea-Pérez, Francisco R; Vallejo, Julia; Julve, Miguel; Lloret, Francesc; De Munno, Giovanni; Armentano, Donatella; Pardo, Emilio

    2013-05-01

    The reaction of N-(2,6-dimethylphenyl)oxamic acid with dysprosium(III) ions in a controlled basic media afforded the first example of a mononuclear lanthanide oxamate complex exhibiting a field-induced slow magnetic relaxation behavior typical of single-ion magnets (SIMs). The hydrogen-bond-mediated self-assembly of this new bifunctional dysprosium(III) SIM in the solid state provides a unique example of 2D hydrogen-bonded polymer with a herringbone net topology.

  17. Dysprosium-Catalyzed Growth of Single-Walled Carbon Nanotube Arrays on Substrates

    Directory of Open Access Journals (Sweden)

    Qian Yong

    2009-01-01

    Full Text Available Abstract In this letter, we report that dysprosium is an effective catalyst for single-walled carbon nanotubes (SWNTs growth via a chemical vapor deposition (CVD process for the first time. Horizontally superlong well-oriented SWNT arrays on SiO2/Si wafer can be fabricated by EtOH-CVD under suitable conditions. The structure and properties are characterized by scanning electron microscopy, transition electron microscopy, Raman spectroscopy and atomic force microscopy. The results show that the SWNTs from dysprosium have better structural uniformity and better conductivity with fewer defects. This rare earth metal provides not only an alternative catalyst for SWNTs growth, but also a possible method to generate high percentage of superlong semiconducting SWNT arrays for various applications of nanoelectronic device.

  18. Direct Search for keV Sterile Neutrino Dark Matter with a Stable Dysprosium Target

    CERN Document Server

    Lasserre, T; Cribier, M; Merle, A; Mertens, S; Vivier, M

    2016-01-01

    We investigate a new method to search for keV-scale sterile neutrinos that could account for Dark Matter. Neutrinos trapped in our galaxy could be captured on stable $^{163}$Dy if their mass is greater than 2.83~keV. Two experimental realizations are studied, an integral counting of $^{163}$Ho atoms in dysprosium-rich ores and a real-time measurement of the emerging electron spectrum in a dysprosium-based detector. The capture rates are compared to the solar neutrino and radioactive backgrounds. An integral counting experiment using several kilograms of $^{163}$Dy could reach a sensitivity for the sterile-to-active mixing angle $\\sin^2\\theta_{e4}$ of $10^{-5}$ significantly exceeding current laboratory limits. Mixing angles as low as $\\sin^2\\theta_{e4} \\sim 10^{-7}$ / $\\rm m_{^{163}\\rm Dy}\\rm{(ton)}$ could possibly be explored with a real-time experiment.

  19. n-Dodecylammonium bromide monohydrate

    Directory of Open Access Journals (Sweden)

    Wenyan Dan

    2010-04-01

    Full Text Available In the title compound, C12H28N+·Br−·H2O, the ionic pairs formed by n-dodecylammonium cations and bromide anions are arranged into thick layers; these layers are linked in a nearly perpendicular fashion [the angle between the layers is 85.84 (5°] by hydrogen-bonding interactions involving the water molecules. The methylene part of the alkyl chain in the cation adopts an all-trans conformation. In the crystal structure, molecules are linked by intermolecular N—H...Br, O—H...Br and N—H...O hydrogen bonds.

  20. Preparation of Dysprosium Ferrite/Polyacrylamide Magnetic Composite Microsphere and Its Characterization

    Institute of Scientific and Technical Information of China (English)

    Hidehiro Kumazawa; Wang Zhifeng; Zhou Lanxiang; Zhang Hong; Li Yourong; Zhang Ming

    2005-01-01

    Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure, average particle size, morphology of composite microsphere were characterized by FTIR, XRD, TEM and TGA. The magnetic responsibility of composite microsphere was also investigated. The results indicate that the magnetic composite microsphere possess high magnetic responsibility and suspension stability.

  1. {Delta}I = 2 energy staggering in normal deformed dysprosium nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Riley, M.A.; Brown, T.B.; Archer, D.E. [Florida State Univ., Tallahassee, FL (United States)] [and others

    1996-12-31

    Very high spin states (I{ge}50{Dirac_h}) have been observed in {sup 155,156,157}Dy. The long regular band sequences, free from sharp backbending effects, observed in these dysprosium nuclei offer the possibility of investigating the occurence of any {Delta}I = 2 staggering in normal deformed nuclei. Employing the same analysis techniques as used in superdeformed nuclei, certain bands do indeed demonstrate an apparent staggering and this is discussed.

  2. Poly[[[μ3-N′-(carboxymethylethylenediamine-N,N,N′-triacetato]dysprosium(III] trihydrate

    Directory of Open Access Journals (Sweden)

    Xiaomei Zhuang

    2010-11-01

    Full Text Available In the title coordination polymer, {[Dy(C10H13N2O8]·3H2O}n, the dysprosium(III ion is coordinated by two N atoms and six O atoms from three different (carboxymethylethylenediaminetriacetate ligands in a distorted square-antiprismatic geometry. The ligands connect the metal atoms, forming layers parallel to the ab plane. O—H...O hydrogen bonds further assemble adjacent layers into a three-dimensional supramolecular network.

  3. Making two dysprosium atoms rotate - Einstein-de Haas effect revisited

    OpenAIRE

    Górecki, Wojciech; Rzążewski, Kazimierz

    2016-01-01

    We present a numerical study of the behaviour of two magnetic dipolar atoms trapped in a harmonic potential and exhibiting the standard Einstein-de Haas effect while subject to a time dependent homogeneous magnetic field. Using a simplified description of the short range interaction and the full expression for the dipole-dipole forces we show, that under experimentally realisable conditions two dysprosium atoms may be pumped to a high ($l>20$) value of the relative orbital angular momentum.

  4. Phosphor Dysprosium-Doped Layered Double Hydroxides Exchanged with Different Organic Functional Groups

    Directory of Open Access Journals (Sweden)

    David Ricardo Martínez Vargas

    2013-01-01

    Full Text Available The layers of a Zn/Al layered double hydroxide (LDH were doped with Dy3+ cations. Among some compositions, the Zn2+ : Al3+ : Dy3+ molar ratio equal to 30 : 9 : 1 presented a single crystalline phase. Organic anions with carboxylic, amino, sulfate, or phosphate functional groups were intercalated as single layers between LDH layers as confirmed by X-ray diffraction and infrared spectroscopy. Photoluminescence spectra of the nitrate intercalated LDH showed a wide emission band with strong intensity in the yellow region (around 574 nm, originated due to symmetry distortion of the octahedral coordination in dysprosium centers. Moreover, a broad red band emission was also detected apparently due to the presence of zinc oxide. The distorted symmetry of the dysprosium coordination environment, also confirmed by X-ray photoelectron spectroscopy analysis, was modified after the intercalation with phenyl phosphonate (PP, aspartate (Asp, adipate (Adip, and serinate (Ser anions; the emission as measured from PL spectra of these LDH was more intense in the blue region (ca. 486 nm, thus indicating an increase in symmetry of dysprosium octahedrons. The red emission band from zinc oxide kept the same intensity after intercalation of dodecyl sulfate (DDS. An additional emission of unknown origin at λ = 767 nm was present in all LDHs.

  5. Conversion of Alcohols to Bromides by Trimethylsilane and lithium Bromide in Acetone

    Institute of Scientific and Technical Information of China (English)

    Wei Feng; Zhang Xiao-xia; Zhang Qing; Wang Ji-yu; Chen Dai-mo

    2004-01-01

    Conversion of alcohols to alkyl bromides is one of the most frequently used functional group transformation reactions. Phosphorus tribromide is one of the most popular classical reagents.Triphenylphosphine has been used in combination with bromine,carbon tetrabromide,N-halo imides and other bromide compounds as a mild reagents for the preparation of alkyl bromides.More reacently, halotrimethylsilanes were found to be useful for halogenation of alcohols. George A.Olah successfully converted alcohols to bromides with chlorotrimethylsilane/lithium bromide in acetonitrile. But in our research, we found that we got no bromides but methylation products when we planed to convered our substances to bromides according to Gerge's method. We did some experiments, and we found that when the substituent group in the 2-N was donor group,we got the methylation products,but when it was acceptor group,the bromide could be got.(Scheme 1).Then we did some experiments with several other solvents, we found excitedly that when the solvent was acetone ,the bromides could be got even the substituent group was donor.(Scheme 2).When we changed the substances to normal alcohols ,such as ethyl alcohol,benzyl alcohol,isopropyl alcohol and 3,4-dimethoxy benzyl alcohol,we also got the bromides.In conclusion, we found a simple method to convert alcohols to bromides with trimethylsilane/li thium bromide in acetone,which was better than Geroge's method.

  6. Systematic study on surface and magnetostructural changes in Mn-substituted dysprosium ferrite by hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Rekha, G. [Department of Physics, College of Engineering Guindy, Anna University, Sardar Patel Road, Chennai 600025 (India); Tholkappiyan, R. [Department of Physics, College of Engineering Guindy, Anna University, Sardar Patel Road, Chennai 600025 (India); Department of Physics, College of Science, UAE University, Al-Ain 15551 (United Arab Emirates); Vishista, K., E-mail: raovishista@gmail.com [Department of Physics, College of Engineering Guindy, Anna University, Sardar Patel Road, Chennai 600025 (India); Hamed, Fathalla [Department of Physics, College of Science, UAE University, Al-Ain 15551 (United Arab Emirates)

    2016-11-01

    Highlights: • Garnet type Dy{sub 3}Fe{sub 5-x}Mn{sub x}O{sub 12} (x = 0–0.06) nanoparticles of 88.4–86.8 nm were synthesized by hydrothermal method. • The Dy, Mn, Fe and O elements in the ferrites were confirmed from XPS. • The multiple oxidation states of Fe and Mn ions, bonding energy and cationic distributions of the samples were examined by XPS. • The magnetic property shows ferromagnetic behavior from VSM technique. • The results from these studies are correlated with respect to Mn dopant. - Abstract: Dysprosium iron garnets are of scientific importance because of the wide range of magnetic properties that can be obtained in substituting dysprosium by a rare earth metal. In the present work, the effect of Mn substitution on magnetostructural changes in dysprosium ferrite nanoparticles is studied. Highly crystalline pure and Mn doped dysprosium ferrite nanoparticles were synthesized by hydrothermal method. The samples were calcined at 1100 °C for 2 h in air atmosphere which is followed by characterization using XRD, FT-IR analysis, SEM, XPS and VSM. The average crystallite size of synthesized samples were calculated by X-ray diffraction falls in the range of 88.4–86.8 nm and was found to be in cubic garnet structure. For further investigation of the structure and corresponding changes in the tetrahedral and octahedral stretching vibrational bonds, FT-IR was used. The synthesized samples consist of multiple oxidation (Fe{sup 3+} and Fe{sup 2+}) states for Fe ions and (Mn{sup 3+} and Mn{sup 2+}) Mn ions analyzed in three ways of Fe 2p and Mn 2p spectra from the XPS analysis. With respect to Mn dopant in Dy{sub 3}Fe{sub 5}O{sub 12}, the cationic distributions of elements were discussed from high resolution XPS spectra by peak position and shift, area, width. To find out the porous/void surface morphology of the sample, scanning electron microscopy was used. From XPS analysis, the presence of elements (Dy, Mn, Fe and O) and their composition in the

  7. Synthesis, structural characterization and in vitro testing of dysprosium containing silica particles as potential MRI contrast enhancing agents

    Energy Technology Data Exchange (ETDEWEB)

    Chiriac, L.B.; Trandafir, D.L. [Faculty of Physics & National Magnetic Resonance Center, Babeş-Bolyai University, Cluj-Napoca, RO-400084 (Romania); Interdisciplinary Research Institute on Bio-Nano-Sciences & Faculty of Physics, Babeş-Bolyai University, Cluj-Napoca, RO-400084 (Romania); Turcu, R.V.F. [Faculty of Physics & National Magnetic Resonance Center, Babeş-Bolyai University, Cluj-Napoca, RO-400084 (Romania); Todea, M. [Interdisciplinary Research Institute on Bio-Nano-Sciences & Faculty of Physics, Babeş-Bolyai University, Cluj-Napoca, RO-400084 (Romania); Simon, S., E-mail: simons@phys.ubbcluj.ro [Faculty of Physics & National Magnetic Resonance Center, Babeş-Bolyai University, Cluj-Napoca, RO-400084 (Romania); Interdisciplinary Research Institute on Bio-Nano-Sciences & Faculty of Physics, Babeş-Bolyai University, Cluj-Napoca, RO-400084 (Romania)

    2016-11-01

    Highlights: • Dysprosium containing silica microparticles obtained by freeze and spray drying. • Higher structural units interconnection achieved in freeze vs. spray dried samples. • Dy occurance on the outermost layer of the microparticles evidenced by XPS. • Enhanced MRI contrast observed for freeze dried samples with 5% mol Dy{sub 2}O{sub 3}. - Abstract: The work is focused on synthesis and structural characterization of novel dysprosium-doped silica particles which could be considered as MRI contrast agents. Sol-gel derived silica rich particles obtained via freeze-drying and spray-drying processing methods were structurally characterized by XRD, {sup 29}Si MAS-NMR and XPS methods. The occurrence of dysprosium on the outermost layer of dysprosium containing silica particles was investigated by XPS analysis. The MRI contrast agent characteristics have been tested using RARE-T{sub 1} and RARE-T{sub 2} protocols. The contrast of MRI images delivered by the investigated samples was correlated with their local structure. Dysprosium disposal on microparticles with surface structure characterised by decreased connectivity of the silicate network units favours dark T{sub 2}-weighted MRI contrast properties.

  8. Pharmacological studies on otilonium bromide.

    Science.gov (United States)

    Giachetti, A

    1991-11-01

    Otilonium bromide (OB) is a quaternary ammonium compound characterized by a long aliphatic chain. Its chemical properties are responsible for both a poor penetration in CNS and a prolonged binding to cell membranes. OB is a spasmolytic agent which acts by modifying Ca++ fluxes from extra and intracellular sites. It has been documented that iv administration (10 mg/kg) of OB causes a marked reduction of colonic motility lasting from 2 to 3 hours, whereas an inhibition of upper GI motor activity is present only at higher dosages. In conclusion, OB seems to exert its activity mainly on distal GI tract, and its spasmolytic effect may be due to its ability to inhibit Ca++ fluxes and to a direct action of the drug on the contractile proteins of the smooth muscle.

  9. Influence of exchange splitting on optical properties in gadolinium and dysprosium single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, Yu.V.; Bolotin, G.A. (AN SSSR, Sverdlovsk. Inst. Fiziki Metallov)

    1984-12-01

    The temperature dependences of optical conductivity in gadolinium and dysprosium single crystals at the light wave vector polarization along a hexagonal axis and in the basis plane are considered. A substantial anisotropy of interzonal absorption has been found. The sample transition into magnetically ordered state is shown to be accompanied by the emergence of resonance absorption peaks in the near infrared spectral region. The manifestation of these peculiarities is associated with quantum electron transitions between the s-, d-f- interaction-split energy bands near the Fermi level. Main peculiarities of the experimental spectrum of gadolinium optical conductivity found their reflection in theoretically calculated dispersion dependence.

  10. Therapeutic application of dysprosium-165-FHMA in the treatment of rheumatoid knee effusions

    Energy Technology Data Exchange (ETDEWEB)

    English, R.J.; Zalutsky, M.; Venkatesan, P.; Sledge, C.B.

    1986-03-01

    Radiation synovectomy utilizing a variety of radionuclides has proven to be an effective technique in the treatment of rheumatoid arthritis. The recent introduction of the short-lived radionuclide, Dysprosium-165 (/sup 165/Dy), as a replacement for the longer-lived radiocolloids has reduced nontarget dosimetry caused by leakage of the agent from the articular cavity. A review of the methods and status of radiation synovectomy, and the application of /sup 165/Dy-ferric hydroxide macroaggregates (FHMA) as an alternative therapeutic agent is described.

  11. Properties of dysprosium-doped gallium lanthanum sulfide fiber amplifiers operating at 1.3 microm.

    Science.gov (United States)

    Samson, B N; Schweizer, T; Hewak, D W; Laming, R I

    1997-05-15

    In light of recent progress in the fabrication of gallium lanthanum sulfide (GaLaS) fibers, we have modeled the performance of dysprosium-doped GaLaS fiber amplifiers operating at 1.3 microm . Based on experimental data, we find that the incorporation of a codopant (terbium) in the fiber core significantly shortens the optimum amplifier length from >30 m to approximately 3 m . Such a device may be practical, given the fiber losses currently achieved in GaLaS fibers.

  12. Isotachophoretic separation of cetyltrimethylammonium bromide.

    Science.gov (United States)

    Praus, Petr

    2005-01-15

    Capillary isotachophoresis (ITP), equipped with the conductivity detection, was tested for the separation of cetyltrimethylamonium (CTMA) bromide. To prevent adsorption of CTMA to the capillary walls, several neutral polymers and ethanol were added into the leading electrolytes. Unlike polymer additives, the CTMA free monomers and micelles, created as a result of the isotachophoretic concentration effect, were recognised in the presence of ethanol from 10 to 25% (v/v). At 30% of ethanol, only a single zone of CTMA monomer was registered because the micellization process did not take place under this condition. Employing an ITP apparatus in the column-coupling configuration, the operational system with 30% of ethanol was tested for the determination of CTMA in hair conditioners. The achieved detection limits were about 0.02mM. Both model solutions and real samples of hair conditioners were analysed with the precision about R.S.D. = 3%. One analysis in the column-coupled system takes circa 15min.

  13. 2,6-Dimethylpyridinium bromide

    Directory of Open Access Journals (Sweden)

    Salim F. Haddad

    2012-10-01

    Full Text Available The asymmetric unit of the title salt, C7H10N+·Br−, comprises two 2,6-dimethylpyridinium cations and two bromide anions. One cation and one anion are situated in general positions, while the other cation and the other anion lie on a crystallographic mirror plane parallel to (010. Each pair of ions interact via N—H...Br and C—H...Br hydrogen bonding, generating motifs depending on the cation and anion involved. Thus, the cation and the anion on the mirror plane generate infinite chains along the c axis, while the other ionic pair leads to sheets parallel to the ac plane. In the overall crystal packing, both motifs alternate along the b axis, with a single layer of the chain motif sandwiched between two double layers of the sheet motif. The sheets and chains are further connected via aryl π–π interactions [centroid–centroid distances = 3.690 (2 and 3.714 (2 Å], giving a three-dimensional network.

  14. Growth and characterization of lead bromide crystals

    Science.gov (United States)

    Singh, N. B.; Gottlieb, M.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.; Glicksman, M. E.; Coriell, S. R.; Santoro, G. J.; Duval, W. M. B.

    1992-01-01

    Lead(II) bromide was purified by a combination of directional freezing and zone-refining methods. Differential thermal analysis of the lead bromide showed that a destructive phase transformation occurs below the melting temperature. This transformation causes extensive cracking, making it very difficult to grow a large single crystal. Energy of phase transformation for pure lead bromide was determined to be 24.67 cal/g. To circumvent this limitation, crystals were doped by silver bromide which decreased the energy of phase transformation. The addition of silver helped in achieving the size, but enhanced the inhomogeneity in the crystal. The acoustic attenuation constant was almost identical for the pure and doped (below 3000 ppm) crystals.

  15. Rapid Synthesis of Glycosyl Bromides by Ultrasound Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jin-zhong; ZHANG Xue-qin; WU Xin; XING Ze-bing; YUE Ai-qin; SHAO Hua-wu

    2013-01-01

    A convenient and environmentally friendly reactor for the synthesis of glycosyl bromides via ultrasound irradiation was designed.Peracetylated glycosyl bromides were synthesized from free saccharides by means of a one-pot method.Benzoylated and 6-subsituted glycosyl bromides were prepared from protected saccharides.The glycosyl bromides were obtained in isolated yields of 83% to 96%.

  16. Effect of dysprosium on the kinetics and structural transformations during the decomposition of the supersaturated solid solution in magnesium-samarium alloys

    Science.gov (United States)

    Rokhlin, L. L.; Luk'yanova, E. A.; Tabachkova, N. Yu.; Dobatkina, T. V.; Tarytina, I. E.; Korol'kova, I. G.

    2017-03-01

    The effect of dysprosium added in the amounts such that it does not form an individual phase in equilibrium with solid magnesium on the decomposition of the supersaturated magnesium solid solution in Mg-Sm alloys is studied. The presence of dysprosium in Mg-Sm alloys is found to retard the decomposition of the supersaturated magnesium solid solution and to increase the hardening effect upon aging. When these alloys are aged, dysprosium is partly retained in the magnesium solid solution and partly enters into the compositions of the phases that form during the decomposition of the solid solution and are characteristic of Mg-Sm alloys.

  17. Cyclic single-molecule magnets: from the odd-numbered heptanuclear to a dimer of heptanuclear dysprosium clusters.

    Science.gov (United States)

    Tian, Haiquan; Bao, Song-Song; Zheng, Li-Min

    2016-02-01

    A heptanuclear and a dimer of heptanuclear dysprosium clusters (Dy7 and Dy14) have been successfully synthesized by ingenious coalescence of the single and double pyrazinyl hydrazone as well as phosphonate ligands. The complexes feature the largest odd-numbered cyclic lanthanide clusters reported thus far. Both exhibit single molecule magnet behaviors at low temperature.

  18. A comparison of the effects of symmetry and magnetoanisotropy on paramagnetic relaxation in related dysprosium single ion magnets.

    Science.gov (United States)

    Williams, Ursula J; Mahoney, Brian D; DeGregorio, Patrick T; Carroll, Patrick J; Nakamaru-Ogiso, Eiko; Kikkawa, James M; Schelter, Eric J

    2012-06-07

    Dysprosium complexes of the tmtaa(2-) ligand were synthesized and characterized by X-band EPR and magnetism studies. Both complexes demonstrate magnetoanisotropy and slow paramagnetic relaxation. Comparison of these compounds with the seminal phthalocyanine complex [Dy(Pc)(2)](-) shows the azaannulide complexes are more susceptible to relaxation through non-thermal pathways.

  19. Dual responsive dysprosium-doped hydroxyapatite particles and toxicity reduction after functionalization with folic and glucuronic acids

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez Lafarga, Ana Karen; Pacheco Moisés, Fermín P. [Departamento de Química, Universidad de Guadalajara, Marcelino García Barragán 1421, C.P. 44430, Guadalajara, Jalisco (Mexico); Gurinov, Andrey [Research Resources Center for Magnetic Resonance, Saint Petersburg State University, Universitetskij pr. 26, 198504 St. Petersburg (Russian Federation); Ortiz, Genaro Gabriel [Laboratorio Desarrollo-Envejecimiento, Enfermedades Neurodegenerativas, Centro de Investigación Biomédica de Occidente (CIBO), Instituto Mexicano de Seguro Social (IMSS), Guadalajara, Jalisco (Mexico); Carbajal Arízaga, Gregorio Guadalupe, E-mail: gregoriocarbajal@yahoo.com.mx [Departamento de Química, Universidad de Guadalajara, Marcelino García Barragán 1421, C.P. 44430, Guadalajara, Jalisco (Mexico)

    2015-03-01

    The development of probes for biomedical applications demands materials with low toxicity levels besides fluorescence or magnetic properties to be detected by confocal microscopes or MRI resonators. Several drug delivery systems or other biomedical materials prepared with hydroxyapatite have been proposed, however, toxicity effects might arise when the size of particles is nanometric. In this study, hydroxyapatite functionalized with glucuronic or folic acids presented lower oxidative stress, measured from lipoperoxides and nitric oxide indicators in rats than pure hydroxyapatite. In separated experiments, hydroxyapatite was doped with dysprosium cations by coprecipitation producing a single crystal phase with fluorescent properties easily visualized by confocal microscopy when excited at 488 nm. These particles also presented the ability to modify the proton relaxation time in T1 maps collected by magnetic resonance imaging. These modified hydroxyapatite nanoparticles could be candidates to design bimodal probes with low toxicity. - Highlights: • Hydroxyapatite functionalized with glucuronic acid reduced oxidative stress in rats. • Functionalization with folic acid reduced oxidative stress in rats. • Dysprosium doping does not affect the crystalline structure of hydroxyapatite. • Dysprosium doped particles are visible in fluorescent microscope. • Dysprosium doped particles act as MRI contrast agents.

  20. Tuning Slow Magnetic Relaxation in a Two-Dimensional Dysprosium Layer Compound through Guest Molecules.

    Science.gov (United States)

    Chen, Qi; Li, Jian; Meng, Yin-Shan; Sun, Hao-Ling; Zhang, Yi-Quan; Sun, Jun-Liang; Gao, Song

    2016-08-15

    A novel two-dimensional dysprosium(III) complex, [Dy(L)(CH3COO)]·0.5DMF·H2O·2CH3OH (1), has been successfully synthesized from a new pyridine-N-oxide (PNO)-containing ligand, namely, N'-(2-hydroxy-3-methoxybenzylidene)pyridine-N-oxidecarbohydrazide (H2L). Single-crystal X-ray diffraction studies reveal that complex 1 is composed of a dinuclear dysprosium subunit, which is further extended by the PNO part of the ligand to form a two-dimensional layer. Magnetic studies indicate that complex 1 shows well-defined temperature- and frequency-dependent signals under a zero direct-current (dc) field, typical of slow magnetic relaxation with an effective energy barrier Ueff of 33.6 K under a zero dc field. Interestingly, powder X-ray diffraction and thermogravimetric analysis reveal that compound 1 undergoes a reversible phase transition that is induced by the desorption and absorption of methanol and water molecules. Moreover, the desolvated sample [Dy(L)(CH3COO)]·0.5DMF (1a) also exhibits slow magnetic relaxation but with a higher anisotropic barrier of 42.0 K, indicating the tuning effect of solvent molecules on slow magnetic relaxation.

  1. Dosimetric properties of dysprosium doped calcium magnesium borate glass subjected to Co-60 gamma ray

    Energy Technology Data Exchange (ETDEWEB)

    Omar, R. S., E-mail: ratnasuffhiyanni@gmail.com; Wagiran, H., E-mail: husin@utm.my; Saeed, M. A. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru (Malaysia)

    2016-01-22

    Thermoluminescence (TL) dosimetric properties of dysprosium doped calcium magnesium borate (CMB:Dy) glass are presented. This study is deemed to understand the application of calcium as the modifier in magnesium borate glass with the presence of dysprosium as the activator to be performed as TL dosimeter (TLD). The study provides fundamental knowledge of a glass system that may lead to perform new TL glass dosimetry application in future research. Calcium magnesium borate glass systems of (70-y) B{sub 2}O{sub 3} − 20 CaO – 10 MgO-(y) Dy{sub 2}O{sub 3} with 0.05  mol % ≤ y ≤ 0.7  mol % of dyprosium were prepared by melt-quenching technique. The amorphous structure and TL properties of the prepared samples were determined using powder X-ray diffraction (XRD) and TL reader; model Harshaw 4500 respectively. The samples were irradiated to Co-60 gamma source at a dose of 50 Gy. Dosimetric properties such as annealing procedure, time temperature profile (TTP) setting, optimization of Dy{sub 2}O{sub 3} concentration of 0.5 mol % were determined for thermoluminescence dosimeter (TLD) reader used.

  2. Palladium-catalyzed cross-coupling of cyclopropylmagnesium bromide with aryl bromides mediated by zinc halide additives.

    Science.gov (United States)

    Shu, Chutian; Sidhu, Kanwar; Zhang, Li; Wang, Xiao-Jun; Krishnamurthy, Dhileepkumar; Senanayake, Chris H

    2010-10-01

    The key Pd-catalyzed cross-coupling of aryl bromides or triflates and cyclopropylmagnesium bromide in the presence of substoichiometric amounts of zinc bromide produces cyclopropyl arenes in good to excellent yields. The cross-coupling of other alkyl, cycloalkyl, and aryl Grignard reagents with aryl bromides under the same conditions gives the corresponding substituted arenes in good yields.

  3. [Pharmacology of the bronchospasmolytic oxitropium bromide].

    Science.gov (United States)

    Bauer, V R

    1985-01-01

    The anticholinergic substance (8r)-6 beta, 7 beta-epoxy-8-ethyl-3 alpha-[(-)-tropoyloxyl]-1 alpha H, 5 alpha H-tropanium bromide (oxitropium bromide, Ba 253 BR, Ventilat) is a competitive antagonist of acetylcholine. In vitro, it is many times as effective as atropine. In vivo, oxitropium bromide, following i.v. administration, is also more effective than atropine. Due to its quaternary structure, a central anticholinergic effect cannot be demonstrated. Furthermore, poor enteral resorption is to be expected. Locally administered, as an aqueous aerosol, the effect of the substance is distinctly greater than that of atropine, both in potency and duration of action. This is also true when administered by metered-dose inhaler compared with ipratropium bromide. As, following aerosol administration, the margin between major effect and the most sensitive side-effect is in the ratio 1 : 100, side-effects are unlikely even with marked inhalational overdosage. Oxitropium bromide can be described, therefore, as a preparation free of side-effects which represents in prophylactic use in many cases of obstructive airway disease, an alternative to beta-mimetics and xanthine derivatives.

  4. [The clinical pharmacological profile of pinaverium bromide].

    Science.gov (United States)

    Guslandi, M

    1994-04-01

    Pinaverium bromide is a locally acting spasmolytic agent of the digestive tract. Its mechanism of action relies upon inhibition of calcium ion entrance into smooth muscle cells (calcium-antagonist effect). In humans pinaverium facilitates gastric emptying and decreases intestinal transit time in patients with constipation. Pinaverium is very effective in improving symptoms of irritable bowel syndrome (abdominal pain, gas, diarrhea or constipation). In this respect the drug proved to be significantly superior to placebo, at least as effective as trimebutine and on the whole more active than otilonium and prifinium bromide, being always extremely well tolerated.

  5. Luminescent properties of dysprosium(Ⅲ) ions in LaAlO3 nanocrystallites

    Institute of Scientific and Technical Information of China (English)

    K. Lema(n)ski; P.J. Dere(n)

    2011-01-01

    The absorption and emission spectra as well as decay time profile of Dy3+ ions in LaAlO3 nanocrystals were analyzed.The crystal structure of LaAlO3 was confirmed from XRD measurement.The emission peaks from blue to red came from main emitting level of dysprosium 4F9/2 to the ground and other excited levels of Dy3+ ions.Cross relaxation process led to non-radiative quenching of luminescence,so that the lifetime of the 4F9/2 energy level ions decreased with increasing amount of doped Dy3+ ions.The cross relaxation transfer rates were experimentally determined as a function of Dy3+ concentration.

  6. Magnetic ordering temperatures in rare earth metal dysprosium under ultrahigh pressures

    Science.gov (United States)

    Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.; Vohra, Yogesh K.

    2014-04-01

    Magnetic ordering temperatures in heavy rare earth metal dysprosium (Dy) have been studied using an ultrasensitive electrical transport measurement technique in a designer diamond anvil cell to a pressure of 69 GPa and a temperature of 10 K. Previous studies using magnetic susceptibility measurements at high pressures were able to track magnetic ordering temperature only till 7 GPa in the hexagonal close packed (hcp) phase of Dy. Our studies indicate that the magnetic ordering temperature shows an abrupt drop of 80 K at the hcp-Sm phase transition followed by a gradual decrease that continues till 17 GPa. This is followed by a rapid increase in the magnetic ordering temperatures in the double hcp phase and finally leveling off in the distorted face centered cubic phase of Dy. Our studies reaffirm that 4f-shell remains localized in Dy and there is no loss of magnetic moment or 4f-shell delocalization for pressures up to 69 GPa.

  7. Electrochemical behaviour of dysprosium in the eutectic LiCl-KCl at W and Al electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Castrillejo, Y. [Dpto de Quimica Analitica, Facultad de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain)]. E-mail: ycastril@qa.uva.es; Bermejo, M.R. [Dpto de Quimica Analitica, Facultad de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Barrado, A.I. [Dpto de Quimica Analitica, Facultad de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Pardo, R. [Dpto de Quimica Analitica, Facultad de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Barrado, E. [Dpto de Quimica Analitica, Facultad de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Martinez, A.M. [Department of Materials Technology, Sem Saelands vei 6, 7491 Trondheim (Norway)

    2005-03-15

    The electrochemical behaviour of DyCl{sub 3} was studied in the eutectic LiCl-KCl at different temperatures. The cathodic reaction can be written:Dy(III)+3e-bar Dy(0)which can be divided in two very close cathodic steps:Dy(III)+1e-bar Dy(II)andDy(II)+2e-bar Dy(0)Transient electrochemical techniques, such as cyclic voltammetry, chronopotentiometry, and chronoamperometry were used in order to study the reaction mechanism and the transport parameters of electroactive species at a tungsten electrode. The results showed that in the eutectic LiCl-KCl, electrocrystallization of dysprosium seems to be the controlling electrochemical step. Chronoamperometric studies indicated instantaneous nucleation of dysprosium with three dimensional growth of the nuclei whatever the applied overpotential.Mass transport towards the electrode is a simple diffusion process, and the diffusion coefficient of the electroactive species, i.e. Dy(III), has been calculated. The validity of the Arrhenius law was also verified by plotting the variation of the logarithm of the diffusion coefficient versus 1/T.In addition, the electrode reactions of the LiCl-KCl-DyCl{sub 3} solutions at an Al wire were also investigated by cyclic voltammetry and open circuit chronopotentiometry. The redox potential of the Dy(III)/Dy couple at the Al electrode was observed at more positive potentials values than those at the inert electrode. This potential shift was thermodynamically analyzed by a lowering of activity of Dy in the metal phase due to the formation of intermetallic compounds.

  8. Electrical polarization of lead bromide crystals. I

    NARCIS (Netherlands)

    Schoonman, A.; Macke, A.J.H.

    1972-01-01

    An attempt was made to measure electronic conductivity in lead bromide in equilibrium with lead, since experimental data on the cell −Pb/PbBr2/C+ in the literature are not consistent with existing theories. Combination of our results with published data for bromine-induced hole conduction in lead br

  9. Electrical polarization of lead bromide crystals. I

    NARCIS (Netherlands)

    Schoonman, A.; Macke, A.J.H.

    An attempt was made to measure electronic conductivity in lead bromide in equilibrium with lead, since experimental data on the cell −Pb/PbBr2/C+ in the literature are not consistent with existing theories. Combination of our results with published data for bromine-induced hole conduction in lead

  10. A comparison of the action of otilonium bromide and pinaverium bromide: study conducted under clinical control.

    Science.gov (United States)

    Defrance, P; Casini, A

    1991-11-01

    We studied 40 patients with irritable bowel syndrome (IBS) which received in a simple-blind fashion otilonium and pinaverium bromide (15 days each drug). During each 15-day period we evaluated: number of pain episodes, intensity of pain, number of bowel movements, side effects. Otilonium bromide, (OB), compared with pinaverium bromide was able to significantly (p less than 0.05) reduce the number of pain attacks, whereas no significant differences were found between the 2 groups as regards the other parameters. The occurrence of side effects was similar in the two treatment courses. We can conclude that the two types of treatment were similarly useful in IBS, although OB seems more effective than pinaverium bromide.

  11. Structural, optical, thermal, mechanical and dielectric studies of Sulfamic acid single crystals: An influence of dysprosium (Dy3+) doping

    Science.gov (United States)

    Singh, Budhendra; Shkir, Mohd.; AlFaify, S.; Kaushal, Ajay; Nasani, Narendar; Bdikin, Igor; Shoukry, H.; Yahia, I. S.; Algarni, H.

    2016-09-01

    Sulfamic acid is a potential material that exhibits excellent optical properties. A good quality, pure and dysprosium (Dy3+) doped (2.5 and 5 mol %) Sulfamic acid (SA) single crystals were grown successfully by slow cooling method. Structural study revealed a slight change in its lattice parameters and volume, suggesting the successful incorporation of Dy3+ in crystal system. The existence of dysprosium in the system was also confirmed. Presence of various vibrational modes was confirmed. Optical transparency was found to have a significant effect with variation in the doping concentration. Furthermore, a marked enhancement in its mechanical parameters with doping was also identified by nanoindentation technique. Etching study was also performed on the grown crystals to study the etch-pit formation and growth mechanism. Effect of doping on the thermal stability was analysed. All the results were compared and discussed in detail to get insight of the effect of doping concentration on Sulfamic acid crystal.

  12. Optical trapping of ultracold dysprosium atoms: transition probabilities, dynamic dipole polarizabilities and van der Waals $C_6$ coefficients

    CERN Document Server

    Li, Hui; Dulieu, Olivier; Nascimbene, Sylvain; Lepers, Maxence

    2016-01-01

    The efficiency of optical trapping of ultracold atoms depend on the atomic dynamic dipole polarizability governing the atom-field interaction. In this article, we have calculated the real and imaginary parts of the dynamic dipole polarizability of dysprosium in the ground and first excited level. Due to the high electronic angular momentum of those two states, the polarizabilities possess scalar, vector and tensor contributions that we have computed, on a wide range of trapping wavelengths, using the sum-over-state formula. Using the same formalism, we have also calculated the $C_6$ coefficients characterizing the van der Waals interaction between two dysprosium atoms in the two lowest levels. We have computed the energies of excited states and the transition probabilities appearing in the sums, using a combination of \\textit{ab initio} and least-square-fitting techniques provided by the Cowan codes and extended in our group. Regarding the real part of the polarizability, for field frequencies far from atomic...

  13. 21 CFR 522.275 - N-Butylscopolammonium bromide.

    Science.gov (United States)

    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...

  14. Mixed (phthalocyaninato)(Schiff-base) di-dysprosium sandwich complexes. Effect of magnetic coupling on the SMM behavior.

    Science.gov (United States)

    Wang, Hailong; Liu, Chenxi; Liu, Tao; Zeng, Suyuan; Cao, Wei; Ma, Qi; Duan, Chunying; Dou, Jianmin; Jiang, Jianzhuang

    2013-11-21

    Reaction between Schiff-base ligand and half-sandwich complex M(Pc)(acac) led to the isolation of new sandwich-type mixed (phthalocyaninato)(Schiff-base) di-lanthanide compounds M2(Pc)2(L)H2O (M = Dy, Gd) (1, 2) [H2Pc = metal free phthalocyanine, Hacac = acetylacetone, H2L = N,N'-bis(3-methyloxysalicylidene)benzene-1,2-diamine] with the triple-decker molecular structure clearly revealed by single crystal X-ray diffraction analysis. For the comparative studies, sandwich triple-decker analogues with pure Schiff-base ligand M2(L)3H2O (M = Dy, Gd) (3, 4) were also prepared. Dynamic magnetic measurement result reveals the single-molecule magnet (SMM) nature of the di-dysprosium derivative 1, while the static magnetic investigation over both pure and the diamagnetic diluted samples of this compound discloses the interionic ferromagnetic coupling between the two dysprosium ions, which in turn effectively suppresses the QTM and enhances the energy barrier of this SMM. Nevertheless, comparative studies over the static magnetic properties of the di-dysprosium triple-decker complexes 1 and 3 indicate the stronger magnetic coupling between the two lanthanide ions in mixed (phthalocyaninato)(Schiff-base) species than in the pure Schiff-base triple-decker analogue, suggesting the special coordination sphere around the dysprosium ions in the former compound over the latter one on the more intense inter-ionic ferromagnetic coupling. As a very small step towards understanding the structure-property relationship, the present result will be surely helpful for the design and synthesis of the multinuclear lanthanide-based SMMs with good properties.

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

    Science.gov (United States)

    2010-07-01

    ... on dog food, resulting from fumigation with methyl bromide. (ii) 125 parts per million for residues... PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances § 180.123 Inorganic bromide residues resulting from... residues of inorganic bromides (calculated as Br) in or on the following food commodities which have been...

  16. Evaluating United States and world consumption of neodymium, dysprosium, terbium, and praseodymium in final products

    Science.gov (United States)

    Hart, Matthew

    This paper develops scenarios of future rare-earth-magnet metal (neodymium, dysprosium, terbium, and praseodymium) consumption in the permanent magnets used in wind turbines and hybrid electric vehicles. The scenarios start with naive base-case scenarios for growth in wind-turbine and hybrid-electric-vehicle sales over the period 2011 to 2020, using historical data for each good. These naive scenarios assume that future growth follows time trends in historical data and does not depend on any exogenous variable. Specifically, growth of each technological market follows historical time trends, and the amount of rare earths used per unit of technology remains fixed. The chosen reference year is 2010. Implied consumptions of the rare earth magnet metals are calculated from these scenarios. Assumptions are made for the material composition of permanent magnets, the market share of permanent-magnet wind turbines and vehicles, and magnet weight per unit of technology. Different scenarios estimate how changes in factors like the material composition of magnets, growth of the economy, and the price of a substitute could affect future consumption. Each scenario presents a different method for reducing rare earth consumption and could be interpreted as potential policy choices. In 2010, the consumption (metric tons, rare-earth-oxide equivalent) of each rare-earth-magnet metal was as follows. Total neodymium consumption in the world for both technologies was 995 tons; dysprosium consumption was 133 tons; terbium consumption was 50 tons; praseodymium consumption was zero tons. The base scenario for wind turbines shows there could be strong, exponential growth in the global wind turbine market. New U.S. sales of hybrid vehicles would decline (in line with the current economic recession) while non-U.S. sales increase through 2020. There would be an overall increase in the total amount of magnetic rare earths consumed in the world. Total consumption of each rare earth in the short

  17. Nitroethylation of vinyl triflates and bromides.

    Science.gov (United States)

    Padilla-Salinas, Rosaura; Walvoord, Ryan R; Tcyrulnikov, Sergei; Kozlowski, Marisa C

    2013-08-02

    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 to nitroethylated products, which are versatile precursors to β,γ-unsaturated carbonyls, homoallylic amines, and nitrile oxides.

  18. Propantheline bromide is effective against dog drooling

    DEFF Research Database (Denmark)

    Gyldenløve, Mette; Thyssen, Jacob P

    2015-01-01

    Hyperhidrosis is a common condition characterized by extensive sweat secretion. Systemic treatment with anticholinergics might prove effective, but patients often suffer from side effects, e.g. dryness of the mouth. We present a clinical case of severe polydipsia in a six-month-old puppy who had ...... accidentally consumed 50 tablets of propantheline bromide 15 mg. Afterwards the puppy suffered from severe polydipsia, which cleared without treatment after three days....

  19. Luminescence features of dysprosium and phosphorus oxide co-doped lithium magnesium borate glass

    Science.gov (United States)

    Hashim, S.; Mhareb, M. H. A.; Ghoshal, S. K.; Alajerami, Y. S. M.; Saripan, M. I.; Bradley, D. A.

    2017-08-01

    Lithium magnesium borate (LMB) glass system co-doped with the oxides of dysprosium (Dy2O3) and phosphorus (P2O5) were synthesized using melt-quenching method. Prepared samples were characterized using various techniques to determine the effects of co-dopants concentration variation on their thermoluminescence (TL) and photoluminescence (PL) properties. TL glow curves of LMB:0.5Dy sample revealed a single prominent peak at Tm=190 °C, where TL intensity was enhanced by a factor of 2.5 with the increase of P2O5 concentration up to 1 mol%. This enhancement was accompanied by a shift in Tm towards higher temperature. Good linearity in the range of 1-100 Gy with linear correlation coefficient of 0.998 was achieved. PL spectra displayed two significant peaks centred at 481 nm and 573 nm. These attractive luminescence features of the proposed glass system may be useful for the development of radiation dosimetry.

  20. Single-molecule magnet behavior for an antiferromagnetically superexchange-coupled dinuclear dysprosium(III) complex.

    Science.gov (United States)

    Long, Jérôme; Habib, Fatemah; Lin, Po-Heng; Korobkov, Ilia; Enright, Gary; Ungur, Liviu; Wernsdorfer, Wolfgang; Chibotaru, Liviu F; Murugesu, Muralee

    2011-04-13

    A family of five dinuclear lanthanide complexes has been synthesized with general formula [Ln(III)(2)(valdien)(2)(NO(3))(2)] where (H(2)valdien = N1,N3-bis(3-methoxysalicylidene)diethylenetriamine) and Ln(III) = Eu(III)1, Gd(III)2, Tb(III)3, Dy(III)4, and Ho(III)5. The magnetic investigations reveal that 4 exhibits single-molecule magnet (SMM) behavior with an anisotropic barrier U(eff) = 76 K. The step-like features in the hysteresis loops observed for 4 reveal an antiferromagnetic exchange coupling between the two dysprosium ions. Ab initio calculations confirm the weak antiferromagnetic interaction with an exchange constant J(Dy-Dy) = -0.21 cm(-1). The observed steps in the hysteresis loops correspond to a weakly coupled system similar to exchange-biased SMMs. The Dy(2) complex is an ideal candidate for the elucidation of slow relaxation of the magnetization mechanism seen in lanthanide systems.

  1. A comparative study of donor formation in dysprosium, holmium, and erbium implanted silicon

    Energy Technology Data Exchange (ETDEWEB)

    Emtsev, V.V.; Emtsev, V.V. Jr.; Poloskin, D.S.; Shek, E.I.; Sobolev, N.A. [Division of Solid State Electronics, Ioffe Physicotechnical Institute, Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation)

    1998-12-01

    Formation of donor centers in Czochralski grown silicon doped with dysprosium, holmium, and erbium is discussed. Donor states of three kinds are introduced in the implanted layers after annealing at T=700C. Shallow donor states with ionization energies between 20 and 40 meV are attributed to oxygen -related thermal donors. Other donor centers in the energy range of E{sub C}-(60...70) meV and E{sub C}-(100...120) meV appear to be dependent on dopants. After a 900C anneal strong changes in the donor formation are observed only in silicon doped with erbium. Instead of donors at E{sub C}-(118{+-}5) meV, new donor centres at E{sub C}-(145{+-}5) meV are formed. Reportedly, the latter ones are involved in the excitation process of the Er{sup 3+} ions with a characteristic luminescence line at {approx}1.54 {mu}m. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  2. Thermoluminescence properties of lithium magnesium borate glasses system doped with dysprosium oxide.

    Science.gov (United States)

    Mhareb, M H A; Hashim, S; Ghoshal, S K; Alajerami, Y S M; Saleh, M A; Razak, N A B; Azizan, S A B

    2015-12-01

    We report the impact of dysprosium (Dy(3+)) dopant and magnesium oxide (MgO) modifier on the thermoluminescent properties of lithium borate (LB) glass via two procedures. The thermoluminescence (TL) glow curves reveal a single prominent peak at 190 °C for 0.5 mol% of Dy(3+). An increase in MgO contents by 10 mol% enhances the TL intensity by a factor of 1.5 times without causing any shift in the maximum temperature. This enhancement is attributed to the occurrence of extra electron traps created via magnesium and the energy transfer to trivalent Dy(3+) ions. Good linearity in the range of 0.01-4 Gy with a linear correlation coefficient of 0.998, fading as low as 21% over a period of 3 months, excellent reproducibility without oven annealing and tissue equivalent effective atomic numbers ~8.71 are achieved. The trap parameters, including geometric factor (μg), activation energy (E) and frequency factor (s) associated with LMB:Dy are also determined. These favorable TL characteristics of prepared glasses may contribute towards the development of Li2O-MgO-B2O3 radiation dosimeters.

  3. Optical properties of zinc borotellurite glass doped with trivalent dysprosium ion

    Science.gov (United States)

    Ami Hazlin, M. N.; Halimah, M. K.; Muhammad, F. D.; Faznny, M. F.

    2017-04-01

    The zinc borotellurite doped with dysprosium oxide glass samples with chemical formula {[(TeO2) 0 . 7(B2O3) 0 . 3 ] 0 . 7(ZnO) 0 . 3 } 1 - x(Dy2O3)x (where x=0.01, 0.02, 0.03, 0.04 and 0.05 M fraction) were prepared by using conventional melt quenching technique. The structural and optical properties of the proposed glass systems were characterized by using X-ray diffraction (XRD) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, and UV-VIS spectroscopy. The amorphous nature of the glass systems is confirmed by using XRD technique. The infrared spectra of the glass systems indicate three obvious absorption bands which are assigned to BO3 and TeO4 vibrational groups. Based on the absorption spectra obtained, the direct and indirect optical band gaps, as well as the Urbach energy were calculated. It is observed that both the direct and indirect optical band gaps increase with the concentration of Dy3+ ions. On the other hand, the Urbach energy is observed to decrease as the concentration of Dy3+ ions increases.

  4. Isolation of {sup 163}Ho from dysprosium target material by HPLC for neutrino mass measurements

    Energy Technology Data Exchange (ETDEWEB)

    Mocko, Veronika; Taylor, Wayne A.; Nortier, Francois M.; Engle, Jonathan W.; Pollington, Anthony D.; Kunde, Gerd J.; Rabin, Michael W.; Birnbaum, Eva R. [Los Alamos National Laboratory, Los Alamos, NM (United States). Chemistry Div.; Barnhart, Todd E.; Nickles, Robert J. [Univ. Wisconsinn, Madison, WI (United States). Dept. of Medical Physics

    2015-07-01

    The rare earth isotope {sup 163}Ho is of interest for neutrino mass measurements. This report describes the isolation of {sup 163}Ho from a proton-irradiated dysprosium target and its purification. A Dy metal target was irradiated with 16 MeV protons for 10 h. After target dissolution, {sup 163}Ho was separated from the bulk Dy via cation-exchange high performance liquid chromatography using 70 mmol dm{sup -3} α-hydroxyisobutyric acid as the mobile phase. Subsequent purification of the collected Ho fraction was performed to remove the α-hydroxyisobutyrate chelating agent and to concentrate the Ho in a low ionic strength aqueous matrix. The final solution was characterized by MC-ICP-MS to determine the {sup 163}Ho/{sup 165}Ho ratio, {sup 163}Ho and the residual Dy content. The HPLC purification process resulted in a decontamination factor 1.4 x 10{sup 5} for Dy. The isolated Ho fraction contained 24.8 ± 1.3 ng of {sup 163}Ho corresponding to holmium recovery of 72 ± 3%.

  5. Reductive cross-coupling of nonaromatic, heterocyclic bromides with aryl and heteroaryl bromides.

    Science.gov (United States)

    Molander, Gary A; Traister, Kaitlin M; O'Neill, Brian T

    2014-06-20

    Reductive cross-coupling allows the direct C-C bond formation between two organic halides without the need for preformation of an organometallic reagent. A method has been developed for the reductive cross-coupling of nonaromatic, heterocyclic bromides with aryl or heteroaryl bromides. The developed conditions use an air-stable Ni(II) source in the presence of a diamine ligand and a metal reductant to allow late-stage incorporation of saturated heterocyclic rings onto aryl halides in a functional-group tolerant manner.

  6. IBS and the role of otilonium bromide.

    Science.gov (United States)

    Boeckxstaens, Guy; Corazziari, Enrico S; Mearin, Fermín; Tack, Jan

    2013-03-01

    Awareness of the seriousness of irritable bowel disorder (IBS) remains low among clinicians. In this review, we summarize the current knowledge of IBS and highlight the major personal, economic, and social burden of the disease, and the importance of adequate treatment of what is still often viewed as a trivial disorder. In fact, IBS is a major reason for referral. It is crucial that the varied pathophysiologies of this complex heterogeneous disease are understood in order to be able to treat both the presenting symptoms (pain, bloating, flatulence, abnormal defecation, diarrhea, constipation) and the underlying disorder effectively. Low-grade inflammatory and immune activation has been observed, but the precise triggers and mechanisms, and the relevance to symptom generation, remain to be established. IBS patients require different treatment strategies according to the pattern, severity, frequency, and symptoms. While initial therapy traditionally targets the most bothersome symptom, long-term therapy aims at maintaining symptom control and preventing recurrence. In addition to dietary/lifestyle interventions and psychosocial strategies, a wide range of pharmacologic therapies are approved for use in IBS depending on the symptoms reported. Musculotropic spasmolytics, which act directly on intestinal smooth muscle contractility, such as otilonium bromide, are effective, particularly in the relief of abdominal pain and bloating, and are well tolerated in IBS. THE OBIS TRIAL: The recent large placebo-controlled Otilonium Bromide in Irritable Bowel Syndrome study demonstrated the superiority of otilonium bromide versus placebo not only in the reduction of pain and bloating, but also in protection from relapse due to the long-lasting effect.

  7. Europium-doped barium bromide iodide

    Energy Technology Data Exchange (ETDEWEB)

    Gundiah, Gautam; Hanrahan, Stephen M.; Hollander, Fredrick J.; Bourret-Courchesne, Edith D.

    2009-10-21

    Single crystals of Ba0.96Eu0.04BrI (barium europium bromide iodide) were grown by the Bridgman technique. The title compound adopts the ordered PbCl2 structure [Braekken (1932). Z. Kristallogr. 83, 222-282]. All atoms occupy the fourfold special positions (4c, site symmetry m) of the space group Pnma with a statistical distribution of Ba and Eu. They lie on the mirror planes, perpendicular to the b axis at y = +-0.25. Each cation is coordinated by nine anions in a tricapped trigonal prismatic arrangement.

  8. EFFICACY OF HYOSCINE BUTYL BROMIDE SUPPOSITORY FOR POSTOPERATIVE PAIN RELIEF

    National Research Council Canada - National Science Library

    Soniya C. Alphonse; Acka Priya Varghese

    2017-01-01

    .... MATERIALS AND METHODS The study is a prospective randomized controlled study conducted at a tertiary care hospital to study the effect of Hyoscine Butyl Bromide Suppositories for postoperative...

  9. Acute dysprosium toxicity to Daphnia pulex and Hyalella azteca and development of the biotic ligand approach.

    Science.gov (United States)

    Vukov, Oliver; Smith, D Scott; McGeer, James C

    2016-01-01

    The toxicological understanding of rare earth elements (REEs) in the aquatic environment is very limited but of increasing concern. The objective of this research is to compare the toxicological effect of the REE dysprosium to the freshwater invertebrates Daphnia pulex and Hyalella azteca and in the more sensitive organism, understand the toxicity modifying influence of Ca, Na, Mg, pH and dissolved organic matter (DOM). Standard methods (Environment Canada) were followed for testing and culture in media of intermediate hardness (60mg CaCO3 mg/L) at pH 7.8 with Ca at 0.5, Na 0.5, Mg 0.125 (mM) and 23°C. Acute toxicity tests were done with azteca and D. pulex revealed Hyalella to be 1.4 times more sensitive than Daphnia. Additions of Ca and Na but not Mg provided significant protection against Dy toxicity to Hyalella. Similarly, low pH was associated with reduction in toxicity. Exposures which were pH buffered with and without MOPS were significantly different and indicated that MOPS enhanced Dy toxicity. DOM also mitigated Dy toxicity. Biotic ligand based parameters (LogK values) were calculated based on free ion relationships as determined by geochemical equilibrium modeling software (WHAM ver. 7.02). The logK value for Dy(3+) toxicity to Hyalella was 7.75 while the protective influence of Ca and Na were 3.95 and 4.10, respectively. This study contributes data towards the development of site specific water quality guidelines and criteria for Dy and possibly REEs in general and offers insight into the complex bio-geochemical nature of this element.

  10. Conduction bands and invariant energy gaps in alkali bromides

    NARCIS (Netherlands)

    Boer, P.K. de; Groot, R.A. de

    1998-01-01

    Electronic structure calculations of the alkali bromides LiBr, NaBr, KBr, RbBr and CsBr are reported. It is shown that the conduction band has primarily bromine character. The size of the band gaps of bromides and alkali halides in general is reinterpreted.

  11. Optical trapping of ultracold dysprosium atoms: transition probabilities, dynamic dipole polarizabilities and van der Waals C 6 coefficients

    Science.gov (United States)

    Li, H.; Wyart, J.-F.; Dulieu, O.; Nascimbène, S.; Lepers, M.

    2017-01-01

    The efficiency of the optical trapping of ultracold atoms depends on the atomic dynamic dipole polarizability governing the atom-field interaction. In this article, we have calculated the real and imaginary parts of the dynamic dipole polarizability of dysprosium in the ground and first excited levels. Due to the high electronic angular momentum of those two states, the polarizabilities possess scalar, vector and tensor contributions that we have computed, on a wide range of trapping wavelengths, using the sum-over-state formula. Using the same formalism, we have also calculated the C 6 coefficients characterizing the van der Waals interaction between two dysprosium atoms in the two lowest levels. We have computed the energies of excited states and the transition probabilities appearing in the sums, using a combination of ab initio and least-square-fitting techniques provided by the Cowan codes and extended in our group. Regarding the real part of the polarizability, for field frequencies far from atomic resonances, the vector and tensor contributions are two-orders-of-magnitude smaller than the scalar contribution, whereas for the imaginary part, the vector and tensor contributions represent a noticeable fraction of the scalar contribution. Finally, our anisotropic C 6 coefficients are much smaller than those published in the literature.

  12. Kinetic spectrophotometric determination of bromide in clidinium-c drug

    Institute of Scientific and Technical Information of China (English)

    Ali Sheibani; M. Reza Shishehbore; Zahra Tavakolian Ardakani

    2011-01-01

    A simple, rapid and sensitive method has been described for the determination of the trace amounts of bromide. The method is based on the catalytic effect of bromide ion on the oxidation of methylene blue by bromate in sulfuric acid media. The reaction is monitored spectrophotometrically by measuring the decrease in the absorbance of methylene blue at 665 nm. Bromide was determined in the range of 0.05-1.90 μg/mL with the detection limit of 0.03 μg/mL. The relative standard deviations of five replicate determinations of 0.20 and 10.0 μg/mL of bromide were 2.4% and 1.8%, respectively. The influence of potential interfering ions and substances was studied. The method is applied to the analysis of bromide in clidinium-c tablet as a real sample.

  13. Irritable bowel syndrome: focus on otilonium bromide.

    Science.gov (United States)

    Boeckxstaens, Guy; Clavé, Pere; Corazziari, Enrico S; Tack, Jan

    2014-02-01

    Irritable bowel syndrome is a prevalent and chronic disorder, characterized by recurrent abdominal pain/discomfort, bloating and altered bowel habits. This condition affects an estimated 10-15% of the population worldwide and impacts heavily on a patient's daily life and ability to work, as well as healthcare resource utilization. Drug therapy aimed at correcting the primary symptoms of diarrhea/constipation/bloating may have little effect on abdominal pain, which results from visceral hypersensitivity. Smooth muscle relaxants or antispasmodics decrease the tone and contractility of intestinal smooth muscle, effectively managing abdominal pain. Otilonium bromide has been widely used worldwide and has been found to be safe and well tolerated, and superior to placebo for the reduction of symptoms and the prevention of symptom relapse in patients with irritable bowel syndrome.

  14. Receptor binding profile of Otilonium bromide.

    Science.gov (United States)

    Evangelista, S; Giachetti, A; Chapelain, B; Neliat, G; Maggi, C A

    1998-08-01

    The interaction of Otilonium bromide (OB) with binding sites for 63 different receptors and ion channels in appropriate preparations has been investigated. Experiments were also performed in rat colon, the preferred tissue for OB 'in vivo' uptake after oral administration. Among the receptors investigated OB binds with sub microM affinity to muscarinic M1, M2, M4, M5 and PAF receptors and with microM affinity to the diltiazem binding site on L type Ca2+ channels. In the rat colon OB shows competitive interaction with the verapamil binding site on L type Ca2+ channels and with muscarinic M2 receptors with IC50 of 1020 and 1220 nM, respectively. These findings provide a molecular rationale to explain the spasmolytic action exerted by OB on intestinal smooth muscle. In particular, a combination of antimuscarinic and Ca2+ channel blocker properties seems to best account for the action of this compound.

  15. Acute dysprosium toxicity to Daphnia pulex and Hyalella azteca and development of the biotic ligand approach

    Energy Technology Data Exchange (ETDEWEB)

    Vukov, Oliver, E-mail: vuko3930@mylaurier.ca [Biology Department, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada); Smith, D. Scott [Chemistry Department, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada); McGeer, James C. [Biology Department, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada)

    2016-01-15

    The toxicological understanding of rare earth elements (REEs) in the aquatic environment is very limited but of increasing concern. The objective of this research is to compare the toxicological effect of the REE dysprosium to the freshwater invertebrates Daphnia pulex and Hyalella azteca and in the more sensitive organism, understand the toxicity modifying influence of Ca, Na, Mg, pH and dissolved organic matter (DOM). Standard methods (Environment Canada) were followed for testing and culture in media of intermediate hardness (60 mg CaCO{sub 3} mg/L) at pH 7.8 with Ca at 0.5, Na 0.5, Mg 0.125 (mM) and 23 °C. Acute toxicity tests were done with <24 h old neonates for 48 h in the case of D. pulex and with 2–9 days old offspring for 96 h tests with Hyalella. The potential protective effect of cationic competition was tested with Ca (0.5–2.0 mM), Na (0.5–2.0 mM) and Mg (0.125–0.5 mM). The effect of pH (6.5–8.0) and Suwannee River DOM complexation (at dissolved organic carbon (DOC) concentrations of 9 and 13 mg C/L) were evaluated. Dissolved Dy concentrations were lower than total (unfiltered) indicating precipitation, particularly at higher concentrations. Acute toxicity of Dy to H. azteca and D. pulex revealed Hyalella to be 1.4 times more sensitive than Daphnia. Additions of Ca and Na but not Mg provided significant protection against Dy toxicity to Hyalella. Similarly, low pH was associated with reduction in toxicity. Exposures which were pH buffered with and without MOPS were significantly different and indicated that MOPS enhanced Dy toxicity. DOM also mitigated Dy toxicity. Biotic ligand based parameters (Log K values) were calculated based on free ion relationships as determined by geochemical equilibrium modeling software (WHAM ver. 7.02). The log K value for Dy{sup 3+} toxicity to Hyalella was 7.75 while the protective influence of Ca and Na were 3.95 and 4.10, respectively. This study contributes data towards the development of site specific

  16. White light emission of dysprosium doped lanthanum calcium phosphate oxide and oxyfluoride glasses

    Science.gov (United States)

    Luewarasirikul, N.; Kim, H. J.; Meejitpaisan, P.; Kaewkhao, J.

    2017-04-01

    Lanthanum calcium phosphate oxide and oxyfluoride glasses doped with dysprosium oxide were prepared by melt-quenching technique with chemical composition 20La2O3:10CaO:69P2O5:1Dy2O3 and 20La2O3:10CaF2:69P2O5:1Dy2O3. The physical, optical and luminescence properties of the glass samples were studied to evaluate their potential to using as luminescence materials for solid-state lighting applications. The density, molar volume and refractive index of the glass samples were carried out. The optical and luminescence properties were studied by investigating absorption, excitation, and emission spectra of the glass samples. The absorption spectra were investigated in the UV-Vis-NIR region from 300 to 2000 nm. The excitation spectra observed under 574 nm emission wavelength showed the highest peak centered at 349 nm (6H15/2 → 6P7/2). The emission spectra, excited with 349 nm excitation wavelength showed two major peaks corresponding to 482 nm blue emission (4F9/2 → 6H15/2) and 574 nm yellow emission (4F9/2 → 6H13/2). The experimental lifetime were found to be 0.539 and 0.540 for oxide and oxyfluoride glass sample, respectively. The x,y color coordinates under 349 nm excitation wavelength were (0.38, 0.43) for both glass samples, that be plotted in white region of CIE 1931 chromaticity diagram. The CCT values obtained from the glass samples are 4204 K for oxide glass and 4228 K for oxyfluoride glass corresponding to the commercial cool white light (3100-4500 K). Judd-Ofelt theory had also been employed to obtain the J-O parameters (Ω2, Ω4 and Ω6), oscillator strength, radiative transition possibility, stimulated emission cross section and branching ratio. The Ω2 > Ω4 > Ω6 trend of J-O parameters of both glass samples may indicate the good quality of a glass host for using as optical device application. Temperature dependence of emission spectra was studied from 300 K to 10 K and found that the intensity of the emission peak was found to be increased with

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

    Science.gov (United States)

    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.

  18. Chloride, bromide and iodide scintillators with europium

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2016-09-27

    A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX.sub.3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa.sub.1-yEu.sub.yI.sub.3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA.sub.1-yEu.sub.yX.sub.3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0.ltoreq.y.ltoreq.1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

  19. Selective oxidation of alcohols with alkali metal bromides as bromide catalysts: experimental study of the reaction mechanism.

    Science.gov (United States)

    Moriyama, Katsuhiko; Takemura, Misato; Togo, Hideo

    2014-07-03

    A bromide-catalyzed oxidation of alcohols was developed which proceeded in the presence of an alkali metal bromide and an oxidant under mild conditions. The reaction involved an organic-molecule-free oxidation using KBr and Oxone and a Brønsted acid assisted oxidation using KBr and aqueous H2O2 solution to provide a broad range of carbonyl compounds in high yields. Moreover, the bromide-catalyzed oxidation of primary alcohols enabled the divergent synthesis of carboxylic acids and aldehydes under both reaction conditions in the presence of TEMPO. A possible catalytic mechanism was suggested on the basis of various mechanistic studies.

  20. Limits on violations of Lorentz symmetry and the Einstein equivalence principle using radio-frequency spectroscopy of atomic dysprosium.

    Science.gov (United States)

    Hohensee, M A; Leefer, N; Budker, D; Harabati, C; Dzuba, V A; Flambaum, V V

    2013-08-02

    We report a joint test of local Lorentz invariance and the Einstein equivalence principle for electrons, using long-term measurements of the transition frequency between two nearly degenerate states of atomic dysprosium. We present many-body calculations which demonstrate that the energy splitting of these states is particularly sensitive to violations of both special and general relativity. We limit Lorentz violation for electrons at the level of 10(-17), matching or improving the best laboratory and astrophysical limits by up to a factor of 10, and improve bounds on gravitational redshift anomalies for electrons by 2 orders of magnitude, to 10(-8). With some enhancements, our experiment may be sensitive to Lorentz violation at the level of 9 × 10(-20).

  1. Nonlinear optical properties of lutetium and dysprosium bisphthalocyanines at 1550 nm with femto- and nanosecond pulse excitation

    Science.gov (United States)

    Plekhanov, A. I.; Basova, T. V.; Parkhomenko, R. G.; Gürek, A. G.

    2017-02-01

    In this work, the nonlinear optical properties of unsubstituted lutetium (LuPc2) and dysprosium (DyPc2) bisphthalocyanines as well as octasubstituted Lu(PcR8)2 derivative with R=-S(C6H13) were studied at a wavelength of 1550 nm with 10 ns and 300 fs pulses. Based on Z-scan measurements the nonlinear absorption and refraction coefficient as well as the nature of nonlinear optical properties were analyzed for these materials. Open aperture Z-scan indicates strong two-photon absorption in all three bisphthalocyanines in nano- and femtosecond regimes. With good nonlinear optical coefficients, bisphthalocyanines of rare earth elements are expected to be promising materials for the creation of optical limiters.

  2. Miyaura Borylations of Aryl Bromides in Water at Room Temperature

    OpenAIRE

    Lipshutz, Bruce H.; Moser, Ralph; Voigtritter, Karl R.

    2010-01-01

    New technology for palladium-catalyzed cross-couplings between B2pin2 and aryl bromides leading to arylboronates is described. Micellar catalysis serves to enable borylations to take place in water as the only medium at ambient temperatures.

  3. A new convenient access to highly functionalized ()-2-arylvinyl bromides

    Indian Academy of Sciences (India)

    Yubo Jiang; Chunxiang Kuang

    2009-11-01

    Highly functionalized ()-2-arylvinyl bromides were prepared in high yields through a new convenient access by acylation of ()-4-(2-bromovinyl)phenol with fatty and aromatic acids at room temperature using dicyclohexyl carbodiimide (DCC) and dimethylaminopyridine (DMAP).

  4. Methyl Bromide Commodity Fumigation Buffer Zone Lookup Tables

    Science.gov (United States)

    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.

  5. Homocoupling of Aryl Bromides Catalyzed by Nickel Chloride in Pyridine

    Institute of Scientific and Technical Information of China (English)

    TAO, Xiao-Chun; ZHOU, Wei; ZHANG, Yue-Ping; DAI, Chun-ya; SHEN, Dong; HUANG, Mei

    2006-01-01

    Pyridine was used as a solvent for homocoupling of aryl bromides catalyzed by nickel chloride/triarylphosphine in the presence of zinc and recycled easily. Triphenylphosphine was the best ligand for nickel in this coupling reaction.

  6. Pd-catalyzed nucleophilic fluorination of aryl bromides.

    Science.gov (United States)

    Lee, Hong Geun; Milner, Phillip J; Buchwald, Stephen L

    2014-03-12

    On the basis of mechanism-driven reaction design, a Pd-catalyzed nucleophilic fluorination of aryl bromides and iodides has been developed. The method exhibits a broad substrate scope, especially with respect to nitrogen-containing heteroaryl bromides, and proceeds with minimal formation of the corresponding reduction products. A facilitated ligand modification process was shown to be critical to the success of the reaction.

  7. Disinfection byproduct regulatory compliance surrogates and bromide-associated risk.

    Science.gov (United States)

    Kolb, Chelsea; Francis, Royce A; VanBriesen, Jeanne M

    2017-08-01

    Natural and anthropogenic factors can alter bromide concentrations in drinking water sources. Increasing source water bromide concentrations increases the formation and alters the speciation of disinfection byproducts (DBPs) formed during drinking water treatment. Brominated DBPs are more toxic than their chlorinated analogs, and thus have a greater impact on human health. However, DBPs are regulated based on the mass sum of DBPs within a given class (e.g., trihalomethanes and haloacetic acids), not based on species-specific risk or extent of bromine incorporation. The regulated surrogate measures are intended to protect against not only the species they directly represent, but also against unregulated DBPs that are not routinely measured. Surrogates that do not incorporate effects of increasing bromide may not adequately capture human health risk associated with drinking water when source water bromide is elevated. The present study analyzes trihalomethanes (THMs), measured as TTHM, with varying source water bromide concentrations, and assesses its correlation with brominated THM, TTHM risk and species-specific THM concentrations and associated risk. Alternative potential surrogates are evaluated to assess their ability to capture THM risk under different source water bromide concentration conditions. The results of the present study indicate that TTHM does not adequately capture risk of the regulated species when source water bromide concentrations are elevated, and thus would also likely be an inadequate surrogate for many unregulated brominated species. Alternative surrogate measures, including THM3 and the bromodichloromethane concentration, are more robust surrogates for species-specific THM risk at varying source water bromide concentrations. Copyright © 2017. Published by Elsevier B.V.

  8. Pharmacology of the anticholinergic bronchospasmolytic agent flutropium bromide.

    Science.gov (United States)

    Bauer, R; Fügner, A

    1986-09-01

    The anticholinergic agent (8r)-8-(2-fluoroethyl)-3 alpha-hydroxy-1 alpha H,tropanium bromide benzilic acid ester (flutropium bromide, Ba 598 BR) is a classic competitive antagonist of acetylcholine. In in vitro experiments it is more effective than atropine. In addition there are indications, that flutropium bromide may interfere with the anaphylactic reaction in a certain dose range in vitro. In in vivo experiments for the characterization of the anticholinergic properties flutropium bromide is also somewhat more effective than atropine after parenteral administration. Because of its quaternary structure no central anticholinergic effect is detectable. Furthermore, a poor enteral absorption is to be expected; this can be concluded from the low relative effectiveness after oral administration. After systemic administration, flutropium bromide is only slightly more effective than atropine. The duration of action is longer. After local administration as an aerosol it is superior to atropine with regard to both effectiveness and duration of action. Since in aerosol administration the ratio of the main effect to the most sensitive side effects, inhibition of salivary secretion, is 1:100, no side effects are to be expected even after high inhalational overdoses. Flutropium bromide can therefore be described as a preparation which is free of side effects. When used prophylactically it represents a therapeutic alternative to beta-mimetics and xanthine derivatives for most cases of obstructive airway diseases.

  9. Metastable fragmentation of silver bromide clusters

    Energy Technology Data Exchange (ETDEWEB)

    L' Hermite, J.M.; Rabilloud, F.; Marcou, L.; Labastie, P. [Lab. CAR/IRSAMC, Univ. Paul Sabatier, Toulouse (France)

    2001-06-01

    The abundance spectra and the fragmentation channels of silver bromide clusters have been measured and analyzed. The most abundant species are Ag{sub n}Br{sub n} {sub -} {sub 1}{sup +} and Ag {sub n}Br {sub n} {sub +} {sub 1}{sup -} and Ag {sub 14}Br {sub 13}{sup +} is a magic number, revealing their ionic nature. However, some features depart from what is generally observed for alkali-halide ionic clusters. From a certain size, Ag {sub n}Br {sub n} {sub -} {sub 1}{sup +} is no more the main series, and Ag {sub n}Br {sub n} {sub -} {sub 2,} {sub 3}{sup +} series become almost as important. The fast fragmentation induced by a UV laser makes the cations lose more bromine than silver ions and lead to more silver-rich clusters. Negative ions mass spectra contain also species with more silver atoms than required by stoichiometry. We have investigated the metastable fragmentation of the cations using a new experimental method. The large majority of the cations release mainly a neutral Ag {sub 3}Br {sub 3} cluster. These decay channels are in full agreement with our recent ab initio DFT calculations, which show that Ag {sup +}-Ag {sup +} repulsion is reduced due to a globally attractive interaction of their d orbitals. This effect leads to a particularly stable trimer (AgBr) {sub 3} and to quasi-planar cyclic structures of (AgBr) {sub n} clusters up to n = 6. We have shown that these two features may be extended to other silver halides, to silver hydroxides (AgOH) {sub n}, and to cuprous halide compounds. (orig.)

  10. Spectroscopic data of the 1.8-, 2.9-, and 4.3- mu m transitions in dysprosium-doped gallium lanthanum sulfide glass

    Science.gov (United States)

    Schweizer, T.; Hewak, D. W.; Samson, B. N.; Payne, D. N.

    1996-10-01

    Infrared emission at 1.8, 2.9, and 4.3 mu m is measured in dysprosium-doped gallium lanthanum sulfide (Ga:La:S) glass excited at 815 nm. Emission cross sections were calculated by Judd-Ofelt analysis, the Fuchtbauer-Ladenburg equation, and the theory of McCumber. The sigma tau value for the 4.3- mu m transition is \\similar 4000 times larger in the Ga:La:S glass than in a dysprosium-doped LiYF4 crystal, which has lased on this transition. The large sigma tau value and the recently reported ability of Ga:La:S glass to be fabricated into fiber form show the potential for an efficient, low-threshold mid-infrared fiber laser. The fluorescence peak at 4.3 mu m coincides with the fundamental absorption of atmospheric carbon dioxide, making the glass a potential laser source for gas-sensing applications.

  11. Spectroscopic data of the 1.8-, 2.9-, and 4.3-microm transitions in dysprosium-doped gallium lanthanum sulfide glass.

    Science.gov (United States)

    Schweizer, T; Hewak, D W; Samson, B N; Payne, D N

    1996-10-01

    Infrared emission at 1.8, 2.9, and 4.3 microm is measured in dysprosium-doped gallium lanthanum sulfide (Ga:La:S) glass excited at 815 nm. Emission cross sections were calculated by Judd-Ofelt analysis, the Füchtbauer- Ladenburg equation, and the theory of McCumber. The sigmatau value for the 4.3-microm transition is ~4000 times larger in the Ga:La:S glass than in a dysprosium-doped LiYF(4) crystal, which has lased on this transition. The large sigmatau value and the recently reported ability of Ga:La:S glass to be fabricated into fiber form show the potential for an efficient, low-threshold mid-infrared fiber laser. The f luorescence peak at 4.3 microm coincides with the fundamental absorption of atmospheric carbon dioxide, making the glass a potential laser source for gas-sensing applications.

  12. Assessment of Ethidium bromide and Ethidium monoazide bromide removal from aqueous matrices by adsorption on cupric oxide nanoparticles.

    Science.gov (United States)

    Fakhri, Ali

    2014-06-01

    The present study was undertaken to develop an effective adsorbent and to study the adsorption of Ethidium bromide and Ethidium monoazide bromide from aqueous solution using the CuO nanoparticles. The characteristics of CuO nanoparticles were determined and found to have a surface area 89.59m(2)/g. Operational parameters such as pH, contact time and adsorbent concentration, initial concentration and temperature were also studied. The amount of removal increases with the increase in pH from one to seven and reaches the maximum when the pH is nine. Adsorption data fitted well with the Langmuir, Freundlich and Florry-Huggins models. The results show that the best fit was achieved with the Langmuir isotherm equation with maximum adsorption capacities of 0.868 and 0.662mg/g for Ethidium bromide and Ethidium monoazide bromide, respectively. The adsorption process was found to follow pseudo-second-order kinetics. The calculated thermodynamic parameters, namely ΔG, ΔH and ΔS showed that adsorption of Ethidium bromide and Ethidium monoazide bromide was spontaneous and endothermic under examined conditions.

  13. On-line complexation/cloud point preconcentration for the sensitive determination of dysprosium in urine by flow injection inductively coupled plasma-optical emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Claudia; Cerutti, Soledad; Silva, Maria F. [Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, 5700, San Luis (Argentina); Olsina, Roberto A.; Martinez, Luis D. [Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, 5700, San Luis (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Avda. Rivadavia 1917, CP C1033AAJJ, Buenos Aires (Argentina)

    2003-01-01

    An on-line dysprosium preconcentration and determination system based on the hyphenation of cloud point extraction (CPE) to flow injection analysis (FIA) associated with ICP-OES was studied. For the preconcentration of dysprosium, a Dy(III)-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol complex was formed on-line at pH 9.22 in the presence of nonionic micelles of PONPE-7.5. The micellar system containing the complex was thermostated at 30 C in order to promote phase separation, and the surfactant-rich phase was retained in a microcolumn packed with cotton at pH 9.2. The surfactant-rich phase was eluted with 4 mol L{sup -1} nitric acid at a flow rate of 1.5 mL min{sup -1}, directly in the nebulizer of the plasma. An enhancement factor of 50 was obtained for the preconcentration of 50 mL of sample solution. The detection limit value for the preconcentration of 50 mL of aqueous solution of Dy was 0.03 {mu}g L{sup -1}. The precision for 10 replicate determinations at the 2.0 {mu}g L{sup -1}Dy level was 2.2% relative standard deviation (RSD), calculated from the peak heights obtained. The calibration graph using the preconcentration system for dysprosium was linear with a correlation coefficient of 0.9994 at levels near the detection limits up to at least 100 {mu}g L {sup -1}. The method was successfully applied to the determination of dysprosium in urine. (orig.)

  14. Clinical potential of aclidinium bromide in chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Zhong J

    2014-06-01

    Full Text Available Jun Zhong, Michael Roth Pneumology and Pulmonary Cell Research, Department of Biomedicine and Internal Medicine, University Hospital Basel, Basel, Switzerland Abstract: Chronic obstructive pulmonary disease (COPD is increasing worldwide and is predicted to become the third most frequent cause of death by 2030. Muscarinic receptor antagonists, alone or in combination with long-acting ß2-agonists, are frequently used for COPD therapy. Aclidinium bromide is a novel muscarinic receptor antagonist, and clinical studies indicate that its metabolism is more rapid than that of other muscarinic receptor inhibitors, so systemic side effects are expected to occur less frequently. Aclidinium bromide is well tolerated, and when compared with other muscarinic receptor antagonists, the drug achieves better control of lung function, especially night-time symptoms in COPD patients. This review summarizes the safety profile and side effects reported by recent clinical studies using aclidinium bromide alone. Keywords: aclidinium, tiotropium, side effects, clinical safety

  15. Water- Lithium Bromide-γ- Butyrolactone Absorption Refrigerating Machine

    Science.gov (United States)

    Iyoki, Shigeki; Uemura, Tadashi

    This investigation was carried out in order to find corrosion inhibitors which would be effective in controlling the corrosion for the water-lithium bromide-γ-butyrolactone (20 moles water/1 mole γ-butyrolactone) absorption refrigerating machine. The experiments were carried out on continuous boiling test, intermittent boiling test and galvanic corrosion test with the use of organic inhibitors and inorganic inhibitors in γ-butyrolactone aqueous solution of lithium bromide. The metals used in these corrosion tests were mainly SS 41 and copper. From these experimental results, the most suitable corrosion inhibitors for SS 41 and copper in γ-butyrolactone aqueous solution of lithium bromide Were recognized to be benzotriazole, tolyltriazole and lithium molybdate.

  16. Intensification of sonochemical degradation of malachite green by bromide ions.

    Science.gov (United States)

    Moumeni, Ouarda; Hamdaoui, Oualid

    2012-05-01

    Sonochemical oxidation has been investigated as a viable advanced oxidation process (AOP) for the destruction of various pollutants in water. Ultrasonic irradiation generates ()OH radicals that can recombine, react with other gaseous species present in the cavity, or diffuse out of the bubble into the bulk liquid medium where they are able to react with solute molecules. The extent of degradation of an organic dye such as malachite green (MG) is limited by the quantity of hydroxyl radicals diffused from cavitation bubbles. In this work, the effect of bromide ions on sonolytic degradation of MG was investigated. The obtained results clearly demonstrated the considerable enhancement of sonochemical destruction of MG in the presence of bromide. No significant differences were observed in the presence of chloride and sulfate, excluding the salting-out effect. Positive effect of bromide ions, which increases with increasing bromide level and decreasing MG concentration, is due to the generation of dibromine radical anion (Br(2)(-)) formed by reaction of Br(-) with ()OH radicals followed by rapid complexation with another anion. The generated Br(2)(-) radicals, reactive but less than ()OH, are likely able to migrate far from the cavitation bubbles towards the solution bulk and are suitable for degradation of an organic dye such as MG. Additionally, Br(2)(-) radicals undergo radical-radical recombination at a lesser extent than hydroxyl radicals and would be more available than ()OH for substrate degradation, both at the bubble surface and in the solution bulk. This effect compensates for the lower reactivity of Br(2)(-) compared to ()OH toward organic substrate. Addition of bromide to natural and sea waters induces a slight positive effect on MG degradation. In the absence of bromide, ultrasonic treatment for the removal of MG was promoted in complex matrices such as natural and sea waters.

  17. Glycosylation with Disarmed Glycosyl Bromides Promoted by Iodonium Ions

    DEFF Research Database (Denmark)

    Lanz, Gyrithe; Madsen, Robert

    2016-01-01

    Iodonium ions have been developed for activating glycosyl bromides in the coupling to glycosyl acceptors. The iodonium ions are generated from N-iodosuccinimide and a protic acid such as camphorsulfonic acid or triflic acid, where the latter gives the most reactive promoter system. The couplings...... occur with the release of iodine monobromide, and the best results are obtained with benzoylated glycosyl donors and acceptors. In this way, disarmed glycosyl bromides can serve as glycosyl donors without the use of heavy-metal salts....

  18. Preparation and characterization of rosin glycerin ester and its bromide

    Institute of Scientific and Technical Information of China (English)

    Yu Caili; Zhang Faai

    2006-01-01

    Rosin glycerin ester and its bromide were prepared from natural renewable rosin,glycerin and liquid bromine which were first subjected to an esterification reaction,followed by an addition reaction.Their structures were characterized by an infrared(IR)spectrum and their thermal resistance was conducted with thermal gravity(TG)and differential scanning calorimetry(DSC).It showed that the bromide in the rosin glycerin ester decomposed faster than the ester;hence it may be used as fire-resistant material.

  19. Synthesis and Crystal Structure of Tri-(2-mercaptopyridine N-oxide)bis(dimethyl sulfoxide) Dysprosium(Ⅲ)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A range of rare earth metal complexes of 2-mercaptopyridine N-oxide (Hmpo) have been synthesized, and studied by elemental analysis and IR spectroscopic technique. Crystal structure of Dy(mpo)3(DMSO)2 (DMSO = dimethyl sulfoxide) has been determined. The complex crystallizes in the triclinic system, space group Pī with lattice parameters: a = 9.602(3), b = 9.803(3), c = 15.498(5)A, α= 89.51(1), β= 85.73(1), γ= 62.99(1)°, Dc = 1.787 g/cm3, C19H24N3O5S5Dy, Mr = 697.21, Z = 2, F(000) = 690, μ = 3.321mm-1, the final R = 0.0237 and wR = 0.0587 for 4116 reflections with I>σ2(I). The coordination number of dysprosium Ⅲ is eight, and its coordination geometry is a somewhat distorted square antiprism with O(3), O(4), O(5), S(3) and O(1), O(2), S(1), S(2) at the tetragonal bases (dihedral angle between their mean planes is 2.9(1)0). Around the Dy atom, three five-membered ring planes (Dy, O, N, C, S) make the dihedral angles of 74.42, 11.31 and 83.72, respectively.

  20. Photo-, cathodo- and thermoluminescent properties of dysprosium-doped HfO2 films deposited by ultrasonic spray pyrolysis.

    Science.gov (United States)

    Manríquez, R Reynoso; Góngora, J A I Díaz; Guzmán-Mendoza, J; Montalvo, T Rivera; Olguín, J C Guzmán; Ramírez, P V Cerón; García-Hipólito, M; Falcony, C

    2014-09-01

    In this work, the photoluminescent (PL), cathodoluminescent (CL) and thermoluminescent (TL) properties of hafnium oxide films doped with trivalent dysprosium ions are reported. The films were deposited on glass substrates at temperatures ranging from 300 to 600°C, using chlorides as precursor reagents. The surface morphology of films showed a veins shaped microstructure at low deposition temperatures, while at higher temperatures the formation of spherical particles was observed on the surface. X-ray diffraction showed the presence of HfO2 monoclinic phase in the films deposited at temperatures greater than 400°C. The PL and CL spectra of the doped films showed the highest emission band centered at 575nm corresponding to the transitions (4)F9/2→(6)H13/2, which is a characteristic transition of Dy(3+) ion. The greatest emission intensities were observed in samples doped with 1 atomic percent (at%) of DyCl3 in the precursor solution. Regarding the TL behavior, the glow curve of HfO2:Dy(+3) films exhibited spectrum with one broad band centered at about 150°C. The highest intensity TL response was observed on the films deposited at 500°C. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Workplace testing of the new single sphere neutron spectrometer based on Dysprosium activation foils (Dy-SSS)

    Science.gov (United States)

    Bedogni, R.; Gómez-Ros, J. M.; Esposito, A.; Gentile, A.; Chiti, M.; Palacios-Pérez, L.; Angelone, M.; Tana, L.

    2012-08-01

    A photon insensitive passive neutron spectrometer consisting of a single moderating polyethylene sphere with Dysprosium activation foils arranged along three perpendicular axes was designed by CIEMAT and INFN. The device is called Dy-SSS (Dy foil-based Single Sphere Spectrometer). It shows nearly isotropic response in terms of neutron fluence up to 20 MeV. The first prototype, previously calibrated with 14 MeV neutrons, has been recently tested in workplaces having different energy and directional distributions. These are a 2.5 MeV nearly mono-chromatic and mono-directional beam available at the ENEA Frascati Neutron Generator (FNG) and the photo-neutron field produced in a 15 MV Varian CLINAC DHX medical accelerator, located in the Ospedale S. Chiara (Pisa). Both neutron spectra are known through measurements with a Bonner Sphere Spectrometer. In both cases the experimental response of the Dy-SSS agrees with the reference data. Moreover, it is demonstrated that the spectrometric capability of the new device are independent from the directional distribution of the neutron field. This opens the way to a new generation of moderation-based neutron instruments, presenting all advantages of the Bonner sphere spectrometer without the disadvantage of the repeated exposures. This concept is being developed within the NESCOFI@BTF project of INFN (Commissione Scientifica Nazionale 5).

  2. Ferroelectric properties of dysprosium-doped Bi4Ti3O12 thin films crystallized in various atmospheres

    Institute of Scientific and Technical Information of China (English)

    CHENG Chuan-pin; TANG Ming-hua; YE Zhi; ZHOU Yic-hun; ZHENG Xue-jun; ZHONG Xiang-li; HU Zeng-shun

    2006-01-01

    Dysprosium-doped Bi4Ti3O12 (Bi3.4Dy0.6Ti3O12,BDT) ferroelectric thin films were deposited on Pt(111)/Ti/SiO2/Si(111) substrates by chemical solution deposition (CSD) and crystallized in nitrogen,air and oxygen atmospheres,respectively. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to identify the crystal structure,the surface and cross-section morphology of the deposited ferroelectric films. The results show that the crystallization atmosphere has significant effect on determining the crystallization and ferroelectric properties of the BDT films. The film crystallized in nitrogen at a relatively low temperature of 650 ℃,exhibits excellent crystallinity and ferroelectricity with a remanent polarization of 2Pr = 24.9 μC/cm2 and a coercive field of 144.5 kV/cm. While the films annealed in air and oxygen at 650 ℃ do not show good crystallinity and ferroelectricity until they are annealed at 700 ℃. The structure evolution and ferroelectric properties of BDT thin films annealed under different temperatures (600-750 ℃) were also investigated. The crystallinity of the BDT films is improved and the average grain size increases when the annealing temperature increases from 600 ℃ to 750 ℃ at an interval of 50 ℃. However,the polarization of the films is not monotonous function of the annealing temperature.

  3. Een ionchromatografische methode voor de simultane bepaling van nitriet, bromide en sulfiet in water

    NARCIS (Netherlands)

    Beld WA van den; Cleven RFMJ; LAC

    1996-01-01

    Betreft resultaten van een onderzoek naar het ontwikkelen van een geautomatiseerde ionchromatografische methode voor de bepaling van nitriet, bromide en sulfiet. Het onderzoek heeft geresulteerd in een betrouwbare, selectieve en gevoelige methode voor de simultane bepaling van nitriet, bromide e

  4. 77 FR 20752 - Methyl Bromide; Proposed Pesticide Tolerance

    Science.gov (United States)

    2012-04-06

    ... necessary to prevent the introduction of a plant pest into the United States or the dissemination of a plant... partition into organic vs. aqueous environments, and is therefore commonly used to predict the likelihood...). See the February 22, 2002, Residue Chemistry Chapter for the methyl bromide RED available in...

  5. Direct acylation of aryl bromides with aldehydes by palladium catalysis.

    Science.gov (United States)

    Ruan, Jiwu; Saidi, Ourida; Iggo, Jonathan A; Xiao, Jianliang

    2008-08-13

    A new protocol for the direct acylation of aryl bromides with aldehydes is established. It appears to involve palladium-amine cooperative catalysis, affording synthetically important alkyl aryl ketones in moderate to excellent yields in a straightforward manner, and broadening the scope of metal-catalyzed coupling reactions.

  6. On the existence of ‘L-alanine cadmium bromide'

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R.

    2013-12-01

    It is argued that the recently reported nonlinear optical crystal L-alanine cadmium bromide, grown by slow solvent evaporation method at room temperature [P. Ilayabarathi, J. Chandrasekaran, Spectrochim. Acta 96A (2012) 684-689] is the well-known L-alanine crystal. The isolation of L-alanine crystal is explained due to fractional crystallization.

  7. On the existence of 'L-alanine cadmium bromide'.

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R

    2013-12-01

    It is argued that the recently reported nonlinear optical crystal L-alanine cadmium bromide, grown by slow solvent evaporation method at room temperature [P. Ilayabarathi, J. Chandrasekaran, Spectrochim. Acta 96A (2012) 684-689] is the well-known L-alanine crystal. The isolation of L-alanine crystal is explained due to fractional crystallization.

  8. Preozonation of bromide-bearing source water in south China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effectiveness of preozonation was evaluated on treating a bromide-bearing dam source water in south China through batch-scale experiments. Preozonation at ozone doses of 0.5-1.0 mg/L (at ozone consumption base) enhanced total organic carbon(TOC) removal through coagulation, and resulted in an almost linear reduction of ultraviolet absorbance at 254 nm (UV254). The removals of TOC (after coagulation) and UV254 at the ozone dose of 1.0 mg/L were 36% and 70%, respectively. Preozonation at an ozone dose between 0.5 and 1.0 mg/L resulted in the removal of disinfection byproducts formation potential (DBFP) including trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP) for about 50%. The removals of THMFP and HAAFP decreased with the further increase of ozone dose. Ozonation of bromide-bearing water (bromide concentration,34 μg/L) produced a bromate concentration under the detection limit(2 μg/L) at ozone doses < 1.5 mg/L. However, bromate >10 μg/L could be produced when the bromide concentration was increased to 96 μg/L.

  9. T-type Ca(2+) channel modulation by otilonium bromide.

    Science.gov (United States)

    Strege, Peter R; Sha, Lei; Beyder, Arthur; Bernard, Cheryl E; Perez-Reyes, Edward; Evangelista, Stefano; Gibbons, Simon J; Szurszewski, Joseph H; Farrugia, Gianrico

    2010-05-01

    Antispasmodics are used clinically to treat a variety of gastrointestinal disorders by inhibition of smooth muscle contraction. The main pathway for smooth muscle Ca(2+) entry is through L-type channels; however, there is increasing evidence that T-type Ca(2+) channels also play a role in regulating contractility. Otilonium bromide, an antispasmodic, has previously been shown to inhibit L-type Ca(2+) channels and colonic contractile activity. The objective of this study was to determine whether otilonium bromide also inhibits T-type Ca(2+) channels. Whole cell currents were recorded by patch-clamp technique from HEK293 cells transfected with cDNAs encoding the T-type Ca(2+) channels, Ca(V)3.1 (alpha1G), Ca(V)3.2 (alpha1H), or Ca(V)3.3 (alpha1I) alpha subunits. Extracellular solution was exchanged with otilonium bromide (10(-8) to 10(-5) M). Otilonium bromide reversibly blocked all T-type Ca(2+) channels with a significantly greater affinity for Ca(V)3.3 than Ca(V)3.1 or Ca(V)3.2. Additionally, the drug slowed inactivation in Ca(V)3.1 and Ca(V)3.3. Inhibition of T-type Ca(2+) channels may contribute to inhibition of contractility by otilonium bromide. This may represent a new mechanism of action for antispasmodics and may contribute to the observed increased clinical effectiveness of antispasmodics compared with selective L-type Ca(2+) channel blockers.

  10. T-type Ca2+ channel modulation by otilonium bromide

    Science.gov (United States)

    Strege, Peter R.; Sha, Lei; Beyder, Arthur; Bernard, Cheryl E.; Perez-Reyes, Edward; Evangelista, Stefano; Gibbons, Simon J.; Szurszewski, Joseph H.

    2010-01-01

    Antispasmodics are used clinically to treat a variety of gastrointestinal disorders by inhibition of smooth muscle contraction. The main pathway for smooth muscle Ca2+ entry is through L-type channels; however, there is increasing evidence that T-type Ca2+ channels also play a role in regulating contractility. Otilonium bromide, an antispasmodic, has previously been shown to inhibit L-type Ca2+ channels and colonic contractile activity. The objective of this study was to determine whether otilonium bromide also inhibits T-type Ca2+ channels. Whole cell currents were recorded by patch-clamp technique from HEK293 cells transfected with cDNAs encoding the T-type Ca2+ channels, CaV3.1 (α1G), CaV3.2 (α1H), or CaV3.3 (α1I) alpha subunits. Extracellular solution was exchanged with otilonium bromide (10−8 to 10−5 M). Otilonium bromide reversibly blocked all T-type Ca2+ channels with a significantly greater affinity for CaV3.3 than CaV3.1 or CaV3.2. Additionally, the drug slowed inactivation in CaV3.1 and CaV3.3. Inhibition of T-type Ca2+ channels may contribute to inhibition of contractility by otilonium bromide. This may represent a new mechanism of action for antispasmodics and may contribute to the observed increased clinical effectiveness of antispasmodics compared with selective L-type Ca2+ channel blockers. PMID:20203058

  11. Silver-catalyzed cross-coupling reactions of alkyl bromides with alkyl or aryl Grignard reagents

    OpenAIRE

    Someya, Hidenori; Yorimitsu, Hideki; Oshima, Koichiro

    2009-01-01

    reatment of secondary or tertiary alkyl bromides with alkyl Grignard reagents in the presence of catalytic amounts of silver bromide and potassium fluoride in CH2Cl2 afforded the corresponding cross-coupling products in reasonable yields. Moreover, silver showed catalytic activity for the cross-coupling reactions of alkyl bromides with aryl Grignard reagents.

  12. Association of defects in lead chloride and lead bromide: Ionic conductivity and dielectric loss measurements

    NARCIS (Netherlands)

    Brom, W.E. van den; Schoonman, J.; Wit, J.H.W. de

    The ionic conductivity data of pure and doped lead bromide without associated defects are used in order to explain the anomalous conductivity behaviour of copper (I) bromide and lead oxide-doped lead-bromide crystals. In these crystals precipitated dopant and associated defects are present. The

  13. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Science.gov (United States)

    2010-07-01

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

  14. Association of defects in lead chloride and lead bromide: Ionic conductivity and dielectric loss measurements

    NARCIS (Netherlands)

    Brom, W.E. van den; Schoonman, J.; Wit, J.H.W. de

    1972-01-01

    The ionic conductivity data of pure and doped lead bromide without associated defects are used in order to explain the anomalous conductivity behaviour of copper (I) bromide and lead oxide-doped lead-bromide crystals. In these crystals precipitated dopant and associated defects are present. The asso

  15. Uptake of ozone to mixed sodium bromide/ citric acid solutions

    Science.gov (United States)

    Lee, Ming-Tao; Steimle, Emilie; Bartels-Rausch, Thorsten; Kato, Shunsuke; Lampimäki, Markus; Brown, Matthew; van Bokhoven, Jeroen; Nolting, Frithjof; Kleibert, Armin; Türler, Andreas; Ammann, Markus

    2013-04-01

    Sea-salt solution - air interfaces play an important role in the chemistry of the marine boundary layer. The reaction of ozone (O3) with bromide is of interest in the context of formation of photolabile halogens (Br2, BrCl) in the marine boundary layer. Recent experiments have suggested that the bromide oxidation rate is related to the surface concentration of bromide [1] and inversely related to the gas phase concentration of O3, an indication for a precursor mediated reaction at the surface [2]. So far, the effect of organics (such as those occurring at the ocean surface or in marine aerosols) on the reaction of O3 with bromide aerosols has not been studied yet. In our study we investigate the uptake kinetics of O3 to a mixed solution of sodium bromide (NaBr) and citric acid (CA), which represents highly oxidized organic compounds present in the environment, with a well-established coated wall flow tube technique, which leads to exposure of the film to O3 allowing the heterogeneous reactions to take place and the loss of O3 being measured. The results indicate that the uptake of O3 to the films with the higher bromide concentrations (0.34M and 4M) is independent of the gas phase concentration and roughly consistent with uptake limited by reaction in the bulk. For the lower bromide concentration (84mM), however, we observe a trend of the uptake coefficient to decrease with increasing O3 concentration, indicating an increasing importance of a surface reaction. In an attempt to constrain the kinetic data, we employed X-ray photoelectron spectroscopy (XPS) to get insight into the surface composition of the aqueous solution - air interface. Previous XPS studies have shown that halide ion concentrations are enhanced at the aqueous solution air interface [3-4], which likely promotes the surface reactions of bromide or iodide with O3. A first XPS study of ternary solutions of KI with butanol indicated the importance of specific interactions of the cation with the alcohol

  16. Sensitive search for the temporal variation of the fine structure constant using radio-frequency E1 transitions in atomic dysprosium

    CERN Document Server

    Nguyen, A T; Lamoreaux, S K; Torgerson, J R

    2003-01-01

    It has been proposed that the radio-frequency electric-dipole (E1) transition between two nearly degenerate opposite-parity states in atomic dysprosium should be highly sensitive to possible temporal variation of the fine structure constant ($\\alpha$) [V. A. Dzuba, V. V. Flambaum, and J. K. Webb, Phys. Rev. A {\\bf 59}, 230 (1999)]. We discuss here an experimental realization of the proposed search, which involves monitoring the E1 transition frequency over a period of time using direct frequency counting techniques. We estimate that a statistical sensitivity of $|\\adota| \\sim 10^{-18}$/yr may be achieved and discuss possible systematic effects in such a measurement.

  17. Synthesis and Crystal Structures of Azolo[b]1,3,4-Thiadiazinium Bromides

    Directory of Open Access Journals (Sweden)

    Gerhard Laus

    2014-12-01

    Full Text Available Three azolo[b]1,3,4-thiadiazinium bromides were prepared from the respective N-amino-N'-methylazolethiones and phenacyl bromide, and their crystal structures were determined. 6-Phenyl-1-methylimidazo[2,1-b]1,3,4-thiadiazinium bromide (1 crystallized as methanol solvate (P21/n, 6-phenyl-1-methyl-1,2,4-triazolo[3,4-b]1,3,4-thiadiazinium bromide (2 as hemi-ethanol solvate (P21/n, and 6-phenyl-1-methyl-1,2,4-triazolo[3,2-b]1,3,4-thiadiazinium bromide (3 solvent-free (P21/c. Interionic contacts were identified.

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

    Science.gov (United States)

    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 (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.

  19. Viscosity and density of some lower alkyl chlorides and bromides

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, W.M.

    1988-07-01

    A high-pressure capillary viscometer, used previously to measure the viscosity of methyl chloride was rebuilt to eliminate the first-order dependence of the measured viscosity on the value assumed for the density of the fluid being investigated. At the same time, the system was arranged so that part of the apparatus could be used to measure density by a volumetric displacement technique. Viscosity and density were measured for ethyl chloride, 1-chloropropane, 1-chlorobutane, methyl bromide, ethyl bromide, and 1-bromopropane. The temperature and pressure ranges of the experiments were 20-150 /sup 0/C and 0.27-6.99 MPa, respectively. The accuracy of the viscosity measurements was estimated to be +-1% and of the density measurements, +-0.2%.

  20. Study of ferroelectric characteristics of diisopropylammonium bromide films

    Science.gov (United States)

    Thirmal, C.; Biswas, P. P.; Shin, Y. J.; Noh, T. W.; Giridharan, N. V.; Venimadhav, A.; Murugavel, P.

    2016-09-01

    Organic molecular ferroelectrics are highly desirable due to their numerous advantages. In the present work, a thick film of diisopropylammonium bromide organic molecular ferroelectric is fabricated on the ITO/glass substrate. The grown film shows preferential orientation along the c-axis with a ferroelectric transition at 419 K. The piezoresponse force microscopic measurements are done in a dual ac resonance tracking mode for its switching characteristics. The amplitude and phase images of the oppositely written domain patterns exhibit a clear contrast with 180° phase difference. The dynamical spectroscopic studies reveal a butterfly loop in amplitude and hysteretic character of the phase which are the expected characteristics features of ferroelectrics. In addition, the macroscopic polarization versus electric field hysteresis gives an additional proof for ferroelectric character of the film with the maximum polarization of 3.5 μC/cm2. Overall, we have successfully fabricated diisopropylammonium bromide organic films and demonstrated its room temperature ferroelectric characteristics.

  1. A novel and robust conditioning lesion induced by ethidium bromide.

    Science.gov (United States)

    Hollis, Edmund R; Ishiko, Nao; Tolentino, Kristine; Doherty, Ernest; Rodriguez, Maria J; Calcutt, Nigel A; Zou, Yimin

    2015-03-01

    Molecular and cellular mechanisms underlying the peripheral conditioning lesion remain unsolved. We show here that injection of a chemical demyelinating agent, ethidium bromide, into the sciatic nerve induces a similar set of regeneration-associated genes and promotes a 2.7-fold greater extent of sensory axon regeneration in the spinal cord than sciatic nerve crush. We found that more severe peripheral demyelination correlates with more severe functional and electrophysiological deficits, but more robust central regeneration. Ethidium bromide injection does not activate macrophages at the demyelinated sciatic nerve site, as observed after nerve crush, but briefly activates macrophages in the dorsal root ganglion. This study provides a new method for investigating the underlying mechanisms of the conditioning response and suggests that loss of the peripheral myelin may be a major signal to change the intrinsic growth state of adult sensory neurons and promote regeneration.

  2. Aluminium Electroplating on Steel from a Fused Bromide Electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Prabhat Tripathy; Laura Wurth; Eric Dufek; Toni Y. Gutknecht; Natalie Gese; Paula Hahn; Steven Frank; Guy Fredrickson; J Stephen Herring

    2014-08-01

    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 in 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.

  3. Preparation of ethyl magnesium bromide for regiospecific analysis of triacylglycerols.

    Science.gov (United States)

    Ando, Yasuhiro; Tomita, Yuki; Haba, Yusuke

    2008-01-01

    This paper presents a procedure for preparation of a Grignard reagent, ethyl magnesium bromide, used for partial deacylation of triacylglycerols (TAG) in their regiospecific analysis. Magnesium turnings were reacted with ethereal solution of bromoethane in a screw-capped test tube to synthesize 2 mL of 1 M ethyl magnesium bromide. Continuously stirred with a vortex mixer, the reaction smoothly proceeded at room temperature. Regiospecific analysis of 1,3-distearoyl-2-oleoylglycerol using this product showed that fatty acid compositions of the sn-1(3) and sn-2 positions were contaminated by less than 2 mol% of fatty acids migrated from isomeric positions. The analyses of lard and cod liver/mackerel oil TAG showed typical distribution patterns of 16:0, 22:5n-3 and 22:6n-3 in pig and fish depot TAG. These results confirmed the view that the freshly prepared reagent is usable for regiospecific analysis of TAG.

  4. Antibacterial Activity of Cetyltrimethylammonium Bromide Modified Silver-Bentonite

    OpenAIRE

    Nik Malek Nik Ahmad Nizam; Azalisa Wan Nur; Yieh Lin Clara Chong

    2016-01-01

    Organo-Ag-bentonite was prepared by the attachment of cationic surfactant cetyltrimethylammonium bromide on silver(A)g-exchanged bentonite. The prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and energy dispersive X-ray (EDX) analysis and antibacterial assay was performed against Escherichia coli in different percentage of saline solutions through minimum inhibition concentration (MIC) method. Organo-Ag-bentonite showed higher ant...

  5. Transformation of bromide in thermo activated persulfate oxidation processes.

    Science.gov (United States)

    Lu, Junhe; Wu, Jinwei; Ji, Yuefei; Kong, Deyang

    2015-07-01

    Sulfate radicals ( [Formula: see text] ) are applied to degrade various organic pollutants. Due to its high oxidative potential, [Formula: see text] is presumed to be able to transform bromide to reactive bromine species that can react with natural organic matter subsequently to form brominated products including brominated disinfection by-products (Br-DBPs). This research was designed to investigate the transformation of bromide in thermo activated persulfate oxidation process in the presence of humic acid (HA). Significant formation of bromoform and bromoacetic acids was verified. Their formation was attributed to the reactions of HA and reactive bromine species including Br·, [Formula: see text] HOBr(-), and free bromine resulted from the oxidation of bromide by [Formula: see text] . Yields of Br-DBPs increased monotonically at persulfate concentration of 1.0 mM and working temperature of 70 °C. However, the time-depended formation exhibited an increasing and the decreasing profile when persulfate was 5.0 mM, suggesting further degradation of organic bromine. HPLC/ICP-MS analysis demonstrated that the organic bromine was eventually transformed to bromate at this condition. Thus, a transformation scheme was proposed in which the bromine could be recycled multiple times between inorganic bromide and organic bromine before being finally transformed to bromate. This is the first study that reveals the comprehensive transformation map of bromine in [Formula: see text] based reaction systems, which should be taken into consideration when such technologies are used to eliminate contamination in real practice.

  6. A Lithium Bromide Absorption Chiller with Cold Storage

    Science.gov (United States)

    2011-01-15

    TO R A G E A LITHIUM BROMIDE ABSORPTION CHILLER WITH COLD STORAGE William Gerstler, et al, General Electric Global Research UNCLASSIFIED UNLIMITED...Research ABSTRACT A LiBr-based absorption chiller can use waste heat or solar energy to produce useful space cooling for small buildings...However, operating this absorption chiller at high ambient tem- peratures may result in performance degradation, crystallization in the absorber, and

  7. COMPARISON OF DROTAVERINE HYDROCHLORIDE AND VALETHAMATE BROMIDE ON CERVICAL DILATATION

    OpenAIRE

    Mallika Selvaraj; Sumathi

    2016-01-01

    AIM To compare the two drugs drotaverine hydrochloride and valethamate bromide and their effects on cervical dilatation and labour duration. METHODOLOGY It is a prospective study undertaken at Government Rajaji Hospital on 150 randomly selected primigravidae patients. RESULTS The duration of active phase of first stage of labour was significantly reduced (p value 0.003), rate of cervical dilatation was higher (p value 0.0001) with drotaverine hydrochloride. CONCLUS...

  8. Water-solubilization of alkyloxo(methoxo)porphyrinatoantimony bromides.

    Science.gov (United States)

    Matsumoto, Jin; Tanimura, Shin-ichiro; Shiragami, Tsutomu; Yasuda, Masahide

    2009-11-14

    In order to develop water-soluble porphyrins, alkyloxo(methoxo)porphyrinatoantimony bromides (alkyl = hexyl (1a), decyl (1b), dodecyl (1c), tetradecyl (1d), octadecyl (1e)) were prepared. 1 had more than 1 mmol dm(-3) of solubility in water. From the dependence of the half-width of the bands in the absorption spectra and surface tension on the concentration of 1, it was estimated that 1b-d were present as aggregates in concentrations higher than 10 micromol dm(-3). From the NMR analysis in D(2)O, it was deduced that the alkyloxo ligands of 1 were arranged alternately in the aggregates. The diameter of the aggregates of 1 in water was determined to be around 100 nm by the dynamic light scattering method. Since the solubilities of di(methoxo)tetraphenylporphyrinatoantimony bromide and 5-(4'-decyloxyphenyl)-10,15,20-triphenylporphyrinato(dimethoxo)antimony(v) bromide were low, it was calculated that the long alkyl axial ligands were requisite for the high solubility in water.

  9. Conservative tracer bromide inhibits pesticide mineralisation in soil.

    Science.gov (United States)

    Bech, Tina B; Rosenbom, Annette E; Sørensen, Sebastian R; Jacobsen, Carsten S

    2017-03-01

    Bromide is a conservative tracer that is often applied with non-conservative solutes such as pesticides to estimate their retardation in the soil. It has been applied in concentrations of up to 250 g Br L(-1), levels at which the growth of single-celled organisms can be inhibited. Bromide applications may therefore affect the biodegradation of non-conservative solutes in soil. The present study investigated the effect of potassium bromide (KBr) on the mineralisation of three pesticides - glyphosate, MCPA and metribuzin - in four agricultural A-horizon soils. KBr was added to soil microcosms at concentrations of 0, 0.5, 2.5 and 5 g Br(-) L(-1) in the soil solution. The study concluded that KBr had a negative effect on pesticide mineralisation. The inhibitory effect varied depending on the KBr concentration, the type of pesticide and the type of soil. Furthermore, 16 S amplicon sequencing revealed that the KBr treatment generally reduced the abundance of bacteroidetes and proteobacteria on both an RNA and DNA level. Therefore, in order to reduce the effect of KBr on the soil bacterial community and consequently also on xenobiotic degradation, it is recommended that KBr be applied in a concentration that does not exceed 0.5 g Br(-) L(-1) in the soil water.

  10. Structural, vibrational and theoretical studies of L-histidine bromide

    Science.gov (United States)

    Ahmed, A. Ben; Feki, H.; Abid, Y.; Boughzala, H.; Mlayah, A.

    2008-10-01

    This paper presents the results of our calculations of the geometric parameters, vibrational spectra and hyperpolarizability of a non linear optical material, L-histidine bromide. Due to the lack of sufficiently precise information on the geometric structure available in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystals of L-histidine bromide have been grown by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro symmetric space group P2 12 12 1 of the orthorhombic system. Raman spectra have been recorded in the range [200-3500 cm -1]. All observed vibrational bands have been discussed and assigned to normal mode or to combinations and overtones on the basis of our calculations. The optimized geometric bond lengths and bond angles obtained by using HF and DFT (B3LYP and BLYP) show good agreement with the experimental data. Comparison between the measured and the calculated vibrational frequencies indicate that B3LYP is superior to the scaled HF approach for molecular vibrational problems. To investigate microscopic second order non linear optical properties of L-histidine bromide, the electric dipole μ, the polarizability α and the hyperpolarizability β were computed using DFT//B3LYP/6-31G(d) method. According to our calculations, the title compound exhibits non-zero β value revealing microscopic second order NLO behaviour.

  11. Oral teratogenicity studies of methyl bromide in rats and rabbits.

    Science.gov (United States)

    Kaneda, M; Hojo, H; Teramoto, S; Maita, K

    1998-05-01

    Teratogenicity studies of methyl bromide, a widely used fumigant, were conducted in rats and rabbits. Methyl bromide was dissolved in corn oil and administered orally to groups of 24 copulated female Crj:CD (SD) rats at dose levels of 0 (corn oil), 3, 10 or 30 mg/kg/day on days 6-15 of gestation and to groups of 18 artificially inseminated female Kbl:JW rabbits at 0, 1, 3 or 10 mg/kg/day on days 6-18 of gestation. Maternal rats and rabbits were euthanized on respective days 20 and 27 of gestation. Foetuses were examined for survival, growth and teratological alterations. Maternal toxicity was evident in the high-dose groups for both species. In these groups, maternal body weight gains and food consumption were significantly decreased during the dosing and post-dosing periods. Necropsy of maternal rats also revealed erosive lesions in the stomach and the surrounding organs. However, no treatment-related adverse effects were found in foetuses of the treated groups for both rat and rabbit studies. These results led to the conclusion that methyl bromide was not foetotoxic or teratogenic to rat and rabbit foetuses up to dose levels of 30 and 10 mg/kg/day, respectively, at which maternal toxicity was evident for both species.

  12. Dysprosium doping induced shape and magnetic anisotropy of Fe3-xDyxO4 (x=0.01-0.1) nanoparticles

    Science.gov (United States)

    Jain, Richa; Luthra, Vandna; Gokhale, Shubha

    2016-09-01

    The effect of dysprosium doping on evolution of structural and magnetic properties of magnetite (Fe3O4) nanoparticles is reported. A standard route of co-precipitation was used for the synthesis of undoped and doped magnetite nanoparticles Fe3-xDyxO4 (x=0.0-0.1). Transmission electron microscopy (TEM) shows formation of round shaped particles with diameter in the range of 8-14 nm for undoped sample. On doping beyond x=0.01, the formation of rod like structures is initiated along with the round shaped particles. The number of rods is found to increase with increasing doping concentration. Magnetic characterization using Vibrating Sample Magnetometer (VSM) revealed doping dependent magnetic properties which can be correlated with the crystallite size as determined from X-ray diffraction (XRD). Enhancement in the saturation magnetization in the initial stages of doping can be explained on the basis of incorporation of Dy3+ ions in the inverse spinel structure at the octahedral site in place of Fe3+ ions. Subsequent decrease in saturation magnetization observed beyond x=0.03 could be attributed to precipitation of excess Dy in form of dysprosium ferrite phase.

  13. Solid miscibility of common-anion lithium and sodium halides. Experimental determination of the region of demixing in lithium bromide + sodium bromide

    NARCIS (Netherlands)

    Oonk, H.A.J.; Wijk, H.J. van; Doornhof, D.

    1984-01-01

    The region of demixing of solid lithium bromide + sodium bromide mixtures has been measured by X-ray diffraction. The critical temperature of mixing corresponding to a thermodynamic fit of the experimental data is 513 K. Estimates are given of the regions of demixing in solid lithium chloride + sodi

  14. On the distribution of bromide and bromide/chlorinity ratios in the waters of the Arabian sea off central Indian coast

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, F.P.; SenGupta, R.

    Water samples from surface to 2000 m depth at two stations in the Arabian Sea collected during the 82nd cruise of R V Gaveshani in November, 1980 were analysed for bromide. The average bromide concentration was 0.068 g/kg plus or minus 0...

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

    Science.gov (United States)

    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.

  16. EFFICACY OF HYOSCINE BUTYL BROMIDE SUPPOSITORY FOR POSTOPERATIVE PAIN RELIEF

    Directory of Open Access Journals (Sweden)

    Soniya C. Alphonse

    2017-07-01

    Full Text Available BACKGROUND Caesarean Section is on the rise all over the world. Women undergoing Caesarean section often wish to be awake post operatively and to avoid excessive medications affecting interactions with the new born infant. Multimodal pain therapy has been advocated for postoperative pain management after caesarean section. MATERIALS AND METHODS The study is a prospective randomized controlled study conducted at a tertiary care hospital to study the effect of Hyoscine Butyl Bromide Suppositories for postoperative analgesia following elective repeat caesarean section. The study included sixty patients divided into two groups- Group1 (study group were given Hyoscine Butyl Bromide Suppository (10 mg along with Injection. Tramadol 50 mg IM and Group II (control group were given Injection Tramadol IM only at the end of surgery. Pain score of the patient assessed at 1 hr, 2 hrs, 6hrs and 24 hrs post operatively. The total no of doses of injection tramadol needed in 24 hrs and the interval between 1st and 2nd dose of tramadol was also noted. The adverse effects of the drug and additional advantages of the drug if any were also assessed. RESULTS There was no statistically significant difference in pain score during the assessment intervals between the two groups. There was no difference in the number of doses of tramadol needed in the first 24 hrs. The mean interval between the 1st and 2nd dose of tramadol was found to be 7.6538 hours for group 1 patients and 6.9130 for group patients which was found to be statistically significant. There was no statistically significant side effects/ additional advantages for the drugs. CONCLUSION Concurrent administration of Hyoscine Butyl Bromide Suppository (10 mg and injection Tramadol 50 mg IM offers a longer postoperative analgesia without any increased adverse effects.

  17. Interaction between gaseous ozone and crystalline potassium bromide

    Science.gov (United States)

    Levanov, A. V.; Maksimov, I. B.; Isaikina, O. Ya.; Antipenko, E. E.; Lunin, V. V.

    2016-07-01

    The formation of nonvolatile products of the oxidation of a bromide ion during the interaction between gaseous ozone and powdered crystalline KBr is studied. It is found that potassium bromate KBrO3 is the main product of the reaction. The influence of major experimental factors (the duration of ozonation, the concentration of ozone, the humidity of the initial gas, and the temperature) on the rate of formation of bromate is studied. The effective constants of the formation of bromate during the interaction between O3 and Br- in a heterogeneous gas-solid body system and in a homogeneous aqueous solution are compared.

  18. Rhodium(NHC)-catalyzed O-arylation of aryl bromides.

    Science.gov (United States)

    Kim, Hyun Jin; Kim, Min; Chang, Sukbok

    2011-05-06

    The first example of the rhodium-catalyzed O-arylation of aryl bromides is reported. While the right combination of rhodium species and N-heterocyclic carbene (NHC) offered an effective catalytic system enabling the arylation to proceed, the choice of NHC was determined to be most important. The developed O-arylation protocol has a wide range of substrate scope, high functional group tolerance, and flexibility allowing a complementary route to either N- or O-arylation depending on the choice of NHC.

  19. DBU-Promoted Trifluoromethylation of Aryl Iodides with Difluoromethyltriphenylphosphonium Bromide

    Institute of Scientific and Technical Information of China (English)

    Yun Wei; Liuying Yu; Jinhong Lin; Xing Zheng; Jichang Xiao

    2016-01-01

    DBU-promoted trifluoromethylation of aryl iodides with difluoromethyltriphenylphosphonium bromide (DFPB) in the presence of copper source is described.In this transformation,DBU not only acts as base to deprotonate the difluoromethyl group in DFPB to generate difluoromethylene phosphonium ylide Ph3P+CF2,but also converts the difluorocarbene generated from ylide Ph3P+CF2 into trifluoromethyl anion,finally resulting in the trifluoromethylation of aryl iodides.The reactions proceeded smoothly to afford expected products in moderate to good yields.

  20. Suicide by intravenous injection of rocuronium-bromide: Case report

    Directory of Open Access Journals (Sweden)

    Nikolić Slobodan

    2005-01-01

    Full Text Available Suicides by intravenous injection of an overdose of medicaments are uncommon. In this paper, we present the case of a suicide by rocuronium-bromide injection in combination with an oral overdose of metoprolol. Unfortunately, in Belgrade, there is no toxicological laboratory capable of detecting rocuronium. The interpretation of autopsy and toxicological data in this case was made difficult due to the extreme putrefaction of the body of the deceased. So, by forensic investigation, the case was solved indirectly, through circumstantial evidence: an empty ampoule of rocuronium found near the body, as well as a plastic syringe and cloth-bandage found in the left hand of the deceased.

  1. COMPARISON OF DROTAVERINE HYDROCHLORIDE AND VALETHAMATE BROMIDE ON CERVICAL DILATATION

    Directory of Open Access Journals (Sweden)

    Mallika Selvaraj

    2016-06-01

    Full Text Available AIM To compare the two drugs drotaverine hydrochloride and valethamate bromide and their effects on cervical dilatation and labour duration. METHODOLOGY It is a prospective study undertaken at Government Rajaji Hospital on 150 randomly selected primigravidae patients. RESULTS The duration of active phase of first stage of labour was significantly reduced (p value 0.003, rate of cervical dilatation was higher (p value 0.0001 with drotaverine hydrochloride. CONCLUSION Drotaverine hydrochloride is a safe, potent and effective drug to be used in the active phase of labour.

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

    Science.gov (United States)

    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.

  3. Transient neuromyopathy after bromide intoxication in a dog with idiopathic epilepsy

    Directory of Open Access Journals (Sweden)

    Steinmetz Sonja

    2012-12-01

    Full Text Available Abstract A seven-year old Australian Shepherd, suffering from idiopathic epilepsy under treatment with phenobarbitone and potassium bromide, was presented with generalised lower motor neuron signs. Electrophysiology and muscle-nerve biopsies revealed a neuromyopathy. The serum bromide concentration was increased more than two-fold above the upper reference value. Clinical signs disappeared after applying diuretics and reducing the potassium bromide dose rate. This is the first case report describing electrophysiological and histopathological findings associated with bromide induced lower motor neuron dysfunction in a dog.

  4. The in vitro and in vivo profile of aclidinium bromide in comparison with glycopyrronium bromide.

    Science.gov (United States)

    Gavaldà, Amadeu; Ramos, Israel; Carcasona, Carla; Calama, Elena; Otal, Raquel; Montero, José Luis; Sentellas, Sonia; Aparici, Monica; Vilella, Dolors; Alberti, Joan; Beleta, Jorge; Miralpeix, Montserrat

    2014-08-01

    This study characterised the in vitro and in vivo profiles of two novel long-acting muscarinic antagonists, aclidinium bromide and glycopyrronium bromide, using tiotropium bromide and ipratropium bromide as comparators. All four antagonists had high affinity for the five muscarinic receptor sub-types (M1-M5); aclidinium had comparable affinity to tiotropium but higher affinity than glycopyrronium and ipratropium for all receptors. Glycopyrronium dissociated faster from recombinant M3 receptors than aclidinium and tiotropium but more slowly than ipratropium; all four compounds dissociated more rapidly from M2 receptors than from M3 receptors. In vitro, aclidinium, glycopyrronium and tiotropium had a long duration of action at native M3 receptors (>8 h versus 42 min for ipratropium). In vivo, all compounds were equi-potent at reversing acetylcholine-induced bronchoconstriction. Aclidinium, glycopyrronium and ipratropium had a faster onset of bronchodilator action than tiotropium. Aclidinium had a longer duration of action than glycopyronnium (time to 50% recovery of effect [t½ offset] = 29 h and 13 h, respectively); these compare with a t½ offset of 64 h and 8 h for tiotropium and ipratropium, respectively. Aclidinium was less potent than glycopyrronium and tiotropium at inhibiting salivation in conscious rats (dose required to produce half-maximal effect [ED50] = 38, 0.74 and 0.88 μg/kg, respectively) and was more rapidly hydrolysed in rat, guinea pig and human plasma compared with glycopyrronium or tiotropium. These results indicate that while aclidinium and glycopyrronium are both potent antagonists at muscarinic receptors with similar kinetic selectivity for M3 receptors versus M2, aclidinium has a longer dissociation half-life at M3 receptors and a longer duration of bronchodilator action in vivo than glycopyrronium. The rapid plasma hydrolysis of aclidinium, coupled to its kinetic selectivity, may confer a reduced propensity for systemic

  5. Octahedral Rotation Preferences in Perovskite Iodides and Bromides.

    Science.gov (United States)

    Young, Joshua; Rondinelli, James M

    2016-03-03

    Phase transitions in ABX3 perovskites are often accompanied by rigid rotations of the corner-connected BX6 octahedral network. Although the mechanisms for the preferred rotation patterns of perovskite oxides are fairly well recognized, the same cannot be said of halide variants (i.e., X = Cl, Br, or I), several of which undergo an unusual displacive transition to a tetragonal phase exhibiting in-phase rotations about one axis (a(0)a(0)c(+) in Glazer notation). To discern the chemical factors stabilizing this unique phase, we investigated a series of 12 perovskite bromides and iodides using density functional theory calculations and compared them with similar oxides. We find that in-phase tilting provides a better arrangement of the larger bromide and iodide anions, which minimizes the electrostatic interactions, improves the bond valence of the A-site cations, and enhances the covalency between the A-site metal and Br(-) or I(-) ions. The opposite effect is present in the oxides, with out-of-phase tilting maximizing these factors.

  6. Development of copper bromide laser master oscillator power amplifier system

    Indian Academy of Sciences (India)

    G N Tiwari; R K Mishra; R Khare; S V Nakhe

    2014-02-01

    Development of master oscillator power amplifier (MOPA) system of copper bromide laser (CBL) operating at 110 W average power is reported. The spectral distribution of power at green (510.6 nm) and yellow (578.2 nm) components in the output of a copper bromide laser is studied as a function of operating parameters. The electrical input power was varied from 2.6 to 4.3 kW, the pulse repetition frequency (PRF) was changed from 16 to 19 kHz, and the pressure of the buffer gas (neon) was kept fixed at 20 mbar. When the electrical input power was increased to 4.3 kW from 2.6 kW, the tube-wall temperature also increased to 488°C from 426°C but the ratio of the green to yellow power decreased to 1.53 from 3.73. The ratio of green to yellow power decreased to 1.53 from 1.63 when the PRF of the laser was increased to 19 kHz from 16 kHz. These observations are explained in terms of electron temperature, energy levels of transitions, and voltage and current waveforms across the laser head.

  7. Single-molecule magnet behavior in an octanuclear dysprosium(iii) aggregate inherited from helical triangular Dy3 SMM-building blocks.

    Science.gov (United States)

    Zhang, Li; Zhang, Peng; Zhao, Lang; Wu, Jianfeng; Guo, Mei; Tang, Jinkui

    2016-06-28

    An unprecedented octanuclear dysprosium(iii) cluster with the formula [Dy8L6(μ3-OH)4(μ2-CH3O)2(CH3OH)6(H2O)2]·6H2O·10CH3OH·2CH3CN () based on a nonlinearly tritopic aroylhydrazone ligand H3L has been isolated, realizing the successful linking of pairwise interesting triangular Dy3 SMMs. It is noteworthy that two enantiomers (Λ and Δ configurations) individually behaving as a coordination-induced chirality presented in the Dy3 helicate are connected in the meso Dy8 cluster. Remarkably, alternating-current magnetic susceptibility measurements revealed that the Dy8 cluster shows typical SMM behavior inherited from its Dy3 helical precursor. It is one of the rare polynuclear Lnn SMMs (n > 7) under zero dc field.

  8. Another challenge to paramagnetic relaxation theory: a study of paramagnetic proton NMR relaxation in closely related series of pyridine-derivatised dysprosium complexes.

    Science.gov (United States)

    Rogers, Nicola J; Finney, Katie-Louise N A; Senanayake, P Kanthi; Parker, David

    2016-02-14

    Measurements of the relaxation rate behaviour of two series of dysprosium complexes have been performed in solution, over the field range 1.0 to 16.5 Tesla. The field dependence has been modelled using Bloch-Redfield-Wangsness theory, allowing estimates of the electronic relaxation time, T1e, and the size of the magnetic susceptibility, μeff, to be made. Changes in relaxation rate of the order of 50% at higher fields were measured, following variation of the para-substituent in the single pyridine donor. The magnetic susceptibilities deviated unexpectedly from the free-ion values for certain derivatives in each series examined, in a manner that was independent of the electron-releasing/withdrawing ability of the pyridine substituent, suggesting that the polarisability of just one pyridine donor in octadenate ligands can play a significant role in defining the magnetic susceptibility anisotropy.

  9. Vapour pressures, densities, and viscosities of the (water + lithium bromide + potassium acetate) system and (water + lithium bromide + sodium lactate) system

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Antonio de [Department of Chemical Engineering, University of Castilla - La Mancha, Avda. de Camilo Jose Cela s/n, 13004 Ciudad Real (Spain); Donate, Marina [Department of Chemical Engineering, University of Castilla - La Mancha, Avda. de Camilo Jose Cela s/n, 13004 Ciudad Real (Spain); Rodriguez, Juan F. [Department of Chemical Engineering, University of Castilla - La Mancha, Avda. de Camilo Jose Cela s/n, 13004 Ciudad Real (Spain)]. E-mail: juan.rromero@uclm.es

    2006-02-15

    Measurements of thermophysical properties (vapour pressure, density, and viscosity) of the (water + lithium bromide + potassium acetate) system LiBr:CH{sub 3}COOK = 2:1 by mass ratio and the (water + lithium bromide + sodium lactate) system LiBr:CH{sub 3}CH(OH)COONa = 2:1 by mass ratio were measured. The system, a possible new working fluid for absorption heat pump, consists of absorbent (LiBr + CH{sub 3}COOK) or (LiBr + CH{sub 3}CH(OH)COONa) and refrigerant H{sub 2}O. The vapour pressures were measured in the ranges of temperature and absorbent concentration from T = (293.15 to 333.15) K and from mass fraction 0.20 to 0.50, densities and viscosities were measured from T = (293.15 to 323.15) K and from mass fraction 0.20 to 0.40. The experimental data were correlated with an Antoine-type equation. Densities and viscosities were measured in the same range of temperature and absorbent concentration as that of the vapour pressure. Regression equations for densities and viscosities were obtained with a minimum mean square error criterion.

  10. The first barium tin(II) bromide fluoride

    Science.gov (United States)

    Dénès, Georges; Merazig, Hocine; Muntasar, Abdualhafeed; Porterfield, Robyn

    2014-04-01

    In an effort to prepare barium tin(II) bromide fluorides for the first time, possibly similar to the chloride fluorides obtained earlier in our laboratory, precipitation reactions were carried out by mixing aqueous solutions of SnF2 and of BaBr2.2H2O. In contrast with the chloride fluoride system, a single powdered phase was obtained throughout the SnF2 - BaBr2 system, with the yield being maximum at X ≈ 0.25, where X is the molar fraction of barium bromide in the reaction mixture. Phase identification with the JCPDS database failed to produce a match, confirming that a new phase had been produced. The exact chemical composition of the new compound has not been obtained yet. Based on the X value for the maximum yield, the Sn/Ba ratio is likely to be 3/1 or 2/1. The Mössbauer spectrum at ambient conditions shows that bonding to tin(II) is covalent, therefore with the tin lone pair being stereoactive. The Mössbauer parameters ( δ = 3.68 mm/s, Δ = 0.99 mm/s) are similar to those of SnBrF and of Sn2BrF5, thereby showing that tin is bonded to both fluorine and bromine. The larger isomer shift and lower quadrupole splitting than in tin(II) fluorides show that the stereoactivity of the tin lone pair is lower than in the fluorides. The Mössbauer parameters fit well the linear correlation of the quadrupole splitting versus the isomer shift" that has been shown to be present in other series of tin(II) compounds. The linear decrease on this correlation shows that the contribution of non-spherical orbitals ( p and d) to the lone pair is a much larger contributor to the quadrupole splitting than lattice distortions. The structure is likely made of Ba2+ cations and tin(II) fluoride bromide polyatomic anions, with covalent bonding withinthe anions.

  11. SYNTHESIS AND CATALYTIC PROPERTIES OF HYDROPHOBICALLY MODIFIED POLY(ALKYLMETHYLDIALLYLAMMONIUM BROMIDES)

    NARCIS (Netherlands)

    YANG, YJ; ENGBERTS, JBFN

    1991-01-01

    A series of hydrophobically modified homo- and copolymers of the poly(alkylmethyldiallylammonium bromide) type has been prepared by free-radical cyclo(co)polymerization of alkylmethyldiallylammonium bromide monomers in aqueous solution. Depending on the length of the alkyl side chain (varied between

  12. Effects of Inhalation or Incubation of Oxitropium Bromide on Diaphragm Muscle Contractility in Mice

    Directory of Open Access Journals (Sweden)

    Chiyohiko Shindoh

    2011-01-01

    Conclusions: We speculate that the increment of muscle contractility with the inhalation of oxitropium bromide was induced by the antagonization of musucarinic acetylcholine receptors (mAChR. In addition, the changes of fatigue resistance provoked by oxitropium bromide, which also is speculated to antagonize mAChR, may be beneficial in the treatment of patients with COPD.

  13. Pancreatitis associated with potassium bromide/phenobarbital combination therapy in epileptic dogs.

    OpenAIRE

    Gaskill, C L; Cribb, A E

    2000-01-01

    In a retrospective study, at least 10% of dogs receiving potassium bromide/phenobarbital combination therapy, compared with 0.3% of dogs receiving phenobarbital monotherapy, had probable pancreatitis. Pancreatitis may be a more frequent and more serious adverse effect of potassium bromide/phenobarbital combination therapy than has been reported previously.

  14. A study of bromide in the Mandovi-Zuari river system of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, F.P.; Dalal, V.N.K.

    concentrations were computed. The variation of bromide with chlorinity was linear indicating the purely conservative character of bromide and its seawater origin. Seawater ranged between 1 and 3% in monsoon, 76 and 91% in post-monsoon and 92 and 97% in pre...

  15. Acrolein as Potential Alternative to Methyl Bromide in California-Grown Calla Lilies

    Science.gov (United States)

    Cut flower and ornamental bulb industries rely heavily on a methyl bromide/chloropicrin (MB/Pic) mixture as a key pest management tool. The loss of methyl bromide (MB) will seriously affect the cut flower and bulb industry, and in the future, will require growers to use alternative fumigants. Theref...

  16. SYNTHESIS AND CATALYTIC PROPERTIES OF HYDROPHOBICALLY MODIFIED POLY(ALKYLMETHYLDIALLYLAMMONIUM BROMIDES)

    NARCIS (Netherlands)

    YANG, YJ; ENGBERTS, JBFN

    1991-01-01

    A series of hydrophobically modified homo- and copolymers of the poly(alkylmethyldiallylammonium bromide) type has been prepared by free-radical cyclo(co)polymerization of alkylmethyldiallylammonium bromide monomers in aqueous solution. Depending on the length of the alkyl side chain (varied between

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

    Science.gov (United States)

    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...

  18. Ammonium Chloride Promoted Palladium-Catalyzed Ullmann Coupling of Aryl Bromide

    Institute of Scientific and Technical Information of China (English)

    李金恒; 梁云; 刘文杰; 唐石; 谢叶香

    2004-01-01

    In water, ammonium chloride was found to promote palladium-catalyzed Ullmann coupling reactions of aryl bromides. In the presence of Pd/C, zinc, NH4Cl, and water, coupling of various aryl bromides was carried out smoothly to afford the corresponding homocoupling products in moderate yields.

  19. Zinc--bromide secondary cell. [C anode, C or Zr cathode with ion exchange diaphragm between

    Energy Technology Data Exchange (ETDEWEB)

    Leddy, J.J.; Gritzner, G.

    1975-12-30

    A zinc-bromine secondary cell is divided into two compartments by an ion exchange diaphragm. The electrolyte system includes an essentially bromide-ion-free, aqueous solution containing a zinc ion as an anolyte and a bromide ion containing catholyte. A method of operating the cell is disclosed. 2 figures, 2 tables. (auth)

  20. Antibacterial Activity of Cetyltrimethylammonium Bromide Modified Silver-Bentonite

    Directory of Open Access Journals (Sweden)

    Nik Malek Nik Ahmad Nizam

    2016-01-01

    Full Text Available Organo-Ag-bentonite was prepared by the attachment of cationic surfactant cetyltrimethylammonium bromide on silver(Ag-exchanged bentonite. The prepared samples were characterized by X-ray diffraction (XRD, Fourier transform infrared (FTIR spectroscopy and energy dispersive X-ray (EDX analysis and antibacterial assay was performed against Escherichia coli in different percentage of saline solutions through minimum inhibition concentration (MIC method. Organo-Ag-bentonite showed higher antibacterial activity than organo-bentonite and Ag-bentonite especially in saline solution suggesting that the precipitation of AgCl in the presence of Ag-bentonite in saline solution could be avoided by the attachment of cationic surfactant on Ag-bentonite surfaces, hence increased their antibacterial activity.

  1. Design and Fabrication of Externally heated Copper Bromide Laser

    Directory of Open Access Journals (Sweden)

    J.P. Dudeja

    1993-04-01

    Full Text Available An externally-heated, longitudinally-discharged, low-repetition-rate copper bromide laser, was designed and fabricated. The green-coloured wavelength at 5106 A from this laser can be used for underwater ranging and detection of submerged objects. Several new changes in the design of discharge tube, heating technique, buffer-gas-flow sub-system and electrical circuit have been conceived and incorporated advantageously in our system. Various parameters, for example, the type of buffer gas and its flow rate, mixture of gases, temperature of the discharge tube, delay between dissociation and excitation pulses, dissociation and excitation energies, and various resonator configurations are being optimised to get the maximum output power/energy from the laser system.

  2. Solvent effects in the reaction between piperazine and benzyl bromide

    Indian Academy of Sciences (India)

    S Ranga Reddy; P Manikyamba

    2007-11-01

    The reaction between piperazine and benzyl bromide was studied conductometrically and the second order rate constants were computed. These rate constants determined in 12 different protic and aprotic solvents indicate that the rate of the reaction is influenced by electrophilicity (), hydrogen bond donor ability () and dipolarity/polarizability (*) of the solvent. The LSER derived from the statistical analysis indicates that the transition state is more solvated than the reactants due to hydrogen bond donation and polarizability of the solvent while the reactant is more solvated than the transition state due to electrophilicity of the solvent. Study of the reaction in methanol, dimethyl formamide mixtures suggests that the rate is maximum when dipolar interactions between the two solvents are maximum.

  3. Xanthine Biosensor Based on Didodecyldimethylammonium Bromide Modified Pyrolytic Graphite Electrode

    Institute of Scientific and Technical Information of China (English)

    TANG,Ji-Lin(唐纪琳); HAN,Xiao-Jun(韩晓军); HUANG,Wei-Min(黄卫民); WANG,Er-Kang(汪尔康)

    2002-01-01

    The vesicle of didodecyldimethylammonium bromide (DDAB)which contained tetrathiafulvalene (TTF) was mixed with xanthine oxidase, and the mixture was cast on the pyrolytic graphite electrode. The lipid films were used to supply a biological environment resembling biomembrane on the surface of the electrode. TTF was used as a mediator because of its high electron-transfer efficiency. A novel xanthine biosensor based on cast DDAB film was developed. The effects of pH and operating potential were explored for optimum analytical performance by using the amperometric method. The response time of the biosensor was less than 10 s. The detection limit of the biosensor was 3.2 × 10-7 mol/L and the liner range was from 4 × 10-7 mol/L to 2.4 × 10-6 mol/L.

  4. Mechanism of the Deaquation of Aquopentaaminocobalt(Ⅲ) Bromide

    Institute of Scientific and Technical Information of China (English)

    MA,Li-Dun(马礼敦); CHENG,Guang-Hui(程广辉); WU,Hong-Xiang(吴宏翔); LIN,Han-Yi(林涵毅); SHEN,Xiao-Liang(沈孝良); SHI,Guo-Shun(施国顺)

    2002-01-01

    There are two theories, SN1 and SN2, for the mechanism of the deaquation of aquopentaamincobalt(Ⅲ) bromide (AAC-B).Both of the theories are supported by some experimental and calculated data. But there are not any experiments to determine directly the structure of the intermediates at different reaction time. In this paper the structures of the intermediates at different reaction time in deaquation-anation of AACB were de-termined by extended X-ray absorption fine structure (EXAFS)and the reaction process wes studied by the combination of Xray powder diffraction and EXAFS. It was demonstrated that the deaquation-anation of AACB obeys the SN2 theory.

  5. Mechanism of the Deaquation of Aquopentaaminocobalt(Ⅲ)Bromide

    Institute of Scientific and Technical Information of China (English)

    MA,Li-Dun; CHENG,Guang-Hui; 等

    2002-01-01

    There are two theories,SN1 and SN2, for the mechanism of the deaquation of aquopentaamincobalt(Ⅲ) bromide(AAC-B). Both of the theories are supported by some experimental and calculated data. But there are not any experiments to determine directly the structure of the intermediates at dififferent reaction time.In this paper the structures of the intermediates at different reaction time in deaquation-anation of AACB were determined by extended X-ray absorption fine structure (EXAFS) and the reaction process was studied by the combination of X-ray powder diffraction and EXAFS.It was demonstrated that the deaquation-anation of AACB obeys the SN2 theory.

  6. Classifying the Basic Parameters of Ultraviolet Copper Bromide Laser

    Science.gov (United States)

    Gocheva-Ilieva, S. G.; Iliev, I. P.; Temelkov, K. A.; Vuchkov, N. K.; Sabotinov, N. V.

    2009-10-01

    The performance of deep ultraviolet copper bromide lasers is of great importance because of their applications in medicine, microbiology, high-precision processing of new materials, high-resolution laser lithography in microelectronics, high-density optical recording of information, laser-induced fluorescence in plasma and wide-gap semiconductors and more. In this paper we present a statistical study on the classification of 12 basic lasing parameters, by using different agglomerative methods of cluster analysis. The results are based on a big amount of experimental data for UV Cu+ Ne-CuBr laser with wavelengths 248.6 nm, 252.9 nm, 260.0 nm and 270.3 nm, obtained in Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences. The relevant influence of parameters on laser generation is also evaluated. The results are applicable in computer modeling and planning the experiments and further laser development with improved output characteristics.

  7. Oral bioavailability and enterohepatic recirculation of otilonium bromide in rats.

    Science.gov (United States)

    Shin, Beom Soo; Kim, Jung Jun; Kim, John; Hu, Sul Ki; Kim, Hyoung Jun; Hong, Seok Hyun; Kim, Han Kyung; Lee, Hye Suk; Yoo, Sun Dong

    2008-01-01

    This study was conducted to examine the oral bioavailability and the possibility of enterohepatic recirculation of otilonium bromide in rats. A sensitive LC/MS/MS assay (LLOQ 0.5 ng/mL) was developed for the determination of otilonium and applied to i.v. and oral administration studies in bile duct cannulated (BDC) and non-BDC rats. After i.v. injection to BDC rats (1 mg/ kg as otilonium), average t(1/2), CL, Vz and AUC were 7.9 +/- 1.9 h, 8.7 +/- 3.1 mL/min/kg, 5.7 +/- 1.4 L/kg and 2,088 +/- 676 ng h/mL, respectively, and these values were comparable to those found in non-BDC rats. The percentages of i.v. dose excreted unchanged in bile and urine in BDC rats were 11.6 +/- 3.0 and 3.1 +/- 0.7%, respectively. Upon oral administration to non-BDC rats (20 mg/kg as otilonium), t(1/2), Cmax, Tmax and AUC were 6.4 +/- 1.3 h, 182.8 +/- 44.6 ng/mL, 1.9 +/- 1.6 h and 579 +/- 113 ng h/mL, respectively. The absolute oral bioavailability was low (1.1%), while the drug was preferentially distributed to gastrointestinal tissues. A secondary peak was observed in the serum concentration-time profiles in non-BDC rats following both i.v. and oral administration, indicating that otilonium bromide was subject to enterohepatic recirculation.

  8. Comparative mobility of sulfonamides and bromide tracer in three soils

    Science.gov (United States)

    Kurwadkar, S.T.; Adams, C.D.; Meyer, M.T.; Kolpin, D.W.

    2011-01-01

    In animal agriculture, sulfonamides are one of the routinely used groups of antimicrobials for therapeutic and sub-therapeutic purposes. It is observed that, the animals when administered the antimicrobials, often do not completely metabolize them; and excrete the partially metabolized forms into the environment. Due to the continued use of antimicrobials and disposal of untreated waste, widespread occurrence of partially metabolized antimicrobials in aquatic and terrestrial environments has been reported in various scientific journals. In this research, the mobility of two sulfonamides - sulfamethazine (SMN), sulfathiazole (STZ) and a conservative bromide tracer was investigated in three soils collected from regions in the United States with large number of concentrated animal-feed operations. Results of a series of column studies indicate that the mobility of these two sulfonamides was dependent on pH, soil charge density, and contact time. At low pH and high charge density, substantial retention of sulfonamides was observed in all three soils investigated, due to the increased fraction of cationic and neutral forms of the sulfonamides. Conversely, enhanced mobility was observed at high pH, where the sulfonamides are predominantly in the anionic form. The results indicate that when both SMN and STZ are predominantly in anionic forms, their mobility approximates the mobility of a conservative bromide tracer. This observation is consistent for the mobility of both SMN and STZ individually, and also in the presence of several other antimicrobials in all three soils investigated. Higher contact time indicates lower mobility due to increased interaction with soil material. ?? 2011.

  9. Gold micro- and nano-particles for surface enhanced vibrational spectroscopy of pyridostigmine bromide

    DEFF Research Database (Denmark)

    Dolgov, Leonid; Fesenko, Olena; Kavelin, Vladyslav

    2017-01-01

    Triangular gold microprisms and spherical silica nanoparticles with attached gold nano-islands were examined as an active nanostructures for the surface enhanced Raman and infrared spectroscopy. These particles were probed for the detection of pyridostigmine bromide as a safe analog of military...... compound sarin. Raman and infrared spectral bands of the pyridostigmine bromide were measured. Detailed correlation of obtained spectral bands with specific vibrations in pyridostigmine bromide was done. Silica nanoparticles with attached gold nano-islands showed more essential enhancement of the Raman...

  10. Highly stereoselective synthesis of functionalized 1,3-dienes from a new allyl bromide

    Directory of Open Access Journals (Sweden)

    Asma Fray

    2014-05-01

    Full Text Available New and highly functionalized 1,3-dienes 3 and 4 have been synthesized via two different pathways starting from allyl bromide 1. Firstly, the reaction of allyl bromide 1 with triethylphosphite leads to an allylphosphonate 2, which undergoes the Wittig-Horner reaction with a range of saturated and unsaturated aldehydes gives rise to the corresponding 1,3-dienes 3. Secondly, a highly stereoselective reaction between allyl bromide 1 and nitroalkane salts, offers the possibility to obtaining functionalized (E-1,3-dienes 4.

  11. Tuning the composition and magnetostructure of dysprosium iron garnets by Co-substitution: An XRD, FT-IR, XPS and VSM study

    Energy Technology Data Exchange (ETDEWEB)

    Tholkappiyan, R.; Vishista, K., E-mail: raovishista@gmail.com

    2015-10-01

    Graphical abstract: - Highlights: • Garnet type Dy{sub 3}Fe{sub 5−x}Co{sub x}O{sub 12} (x = 0–0.06) nanoparticles were synthesized by glycine assisted combustion method. • To investigate and confirm the phases in the synthesized ferrite nanoparticles by FT-IR and XRD analysis. • To investigate the compositional and oxidation state of the samples by X-ray photoelectron spectroscopy. • The detailed core level spectra of Dy 4d, Fe 2p, Co 2p and O 1s were analyzed using XPS. • The magnetic property was studied by VSM technique. - Abstract: We report the Co-substituting on the synthesis and properties of garnet type dysprosium ferrite nanoparticles by basic composition Dy{sub 3}Fe{sub 5−x}Co{sub x}O{sub 12} (x = 0–0.06) synthesized through glycine assisted combustion method. A possible formation mechanism of synthesized Dy{sub 3}Fe{sub 5−x}Co{sub x}O{sub 12} samples by controlling the synthesis process has been proposed. XRD, FT-IR, XPS and VSM studies were used to investigate the compositional and magnetostructural properties of the prepared nanoparticles. XRD results confirm that all the samples are single-phase cubic garnet structure with mean crystallite size of 97–105 nm obtained from Scherrer method and 95–102 nm from W–H method. FT-IR analysis shows the presence of three expected bands in the frequency limit of 450–600 cm{sup −1} attributed to metal–O stretching vibration in tetrahedral site of garnet structure. A typical survey spectrum from XPS results confirmed the presence of Dy, Fe, Co and O elements in the samples. This study also to characterize the different oxidation states of the samples by fitting the parameters of high resolution Dy 4d, Fe 2p, Co 2p and O 1s XPS spectra. The XPS data of Dy 4d spectrum show that Dy{sup 3+} ion occupy in dodecahedral (D) site. The XPS analysis of Fe 2p and Co 2p data suggests that (Fe{sup 3+} and Fe{sup 2+}), (Co{sup 3+} and Co{sup 2+}) are distributed in tetrahedral and octahedral sites

  12. Phytoremediation potentials of selected tropical plants for ethidium bromide.

    Science.gov (United States)

    Uera, Raynato B; Paz-Alberto, Annie Melinda; Sigua, Gilbert C

    2007-11-01

    Research and development has its own benefits and inconveniences. One of the inconveniences is the generation of enormous quantity of diverse toxic and hazardous wastes and its eventual contamination to soil and groundwater resources. Ethidium bromide (EtBr) is one of the commonly used substances in molecular biology experiments. It is highly mutagenic and moderately toxic substance used in DNA-staining during electrophoresis. Interest in phytoremediation as a method to solve chemical contamination has been growing rapidly in recent years. The technology has been utilized to clean up soil and groundwater from heavy metals and other toxic organic compounds in many countries like the United States, Russia, and most of European countries. Phytoremediation requires somewhat limited resources and very useful in treating wide variety of environmental contaminants. This study aimed to assess the potential of selected tropical plants as phytoremediators of EtBr. This study used tomato (Solanum lycopersicum), mustard (Brassica alba), vetivergrass (Vetiveria zizanioedes), cogongrass (Imperata cylindrica), carabaograss (Paspalum conjugatum), and talahib (Saccharum spontaneum) to remove EtBr from laboratory wastes. The six tropical plants were planted in individual plastic bags containing soil and 10% EtBr-stained agarose gel. The plants were allowed to establish and grow in soil for 30 days. Ethidium bromide content of the test plants and the soil were analyzed before and after soil treatment. Ethidium bromide contents of the plants and soils were analyzed using an UV VIS spectrophotometer. Results showed a highly significant (psoils. Mustard registered the highest absorption of EtBr (1.4+/-0.12 microg kg(-1)) followed by tomato and vetivergrass with average uptake of 1.0+/-0.23 and 0.7+/-0.17 microg kg(-1) EtBr, respectively. Cogongrass, talahib, and carabaograss had the least amount of EtBr absorbed (0.2+/-0.6 microg kg(-1)). Ethidium bromide content of soil planted to

  13. Adsorption of anionic polyelectrolytes to dioctadecyldimethylammonium bromide monolayers

    Science.gov (United States)

    Engelking, J.; Menzel, H.

    Monolayers of dioctadecyldimethylammonium bromide (DODA) at the air/water interface were used as model for charged surfaces to study the adsorption of anionic polyelectrolytes. After spreading on a pure water surface the monolayers were compressed and subsequently transferred onto a polyelectrolyte solution employing the Fromherz technique. The polyelectrolyte adsorption was monitored by recording the changes in surface pressure at constant area. For poly(styrene sulfonate) and carboxymethylcellulose the plot of the surface pressure as function of time gave curves which indicate a direct correlation between the adsorbed amount and surface pressure as well as a solely diffusion controlled process. In the case of rigid rod-like poly(p-phenylene sulfonate)s the situation is more complicated. Plotting the surface pressure as function of time results in a curve with sigmoidal shape, characterized by an induction period. The induction period can be explained by a domain formation, which can be treated like a crystallization process. Employing the Avrami expression developed for polymer crystallization, the change in the surface pressure upon adsorption of rigid rod-like poly(p-phenylene sulfonate)s can be described.

  14. Vibrational spectroscopic and computational studies on diisopropylammonium bromide

    Science.gov (United States)

    Sahoo, Shradhanjali; Ravindran, T. R.; Chandra, Sharat; Sarguna, R. M.; Das, B. K.; Sairam, T. N.; Sivasubramanian, V.; Thirmal, C.; Murugavel, P.

    2017-09-01

    Diisopropylammonium bromide (DIPAB) can be crystallized either in an orthorhombic (P212121) or in a monoclinic (P21) structure at room temperature depending on synthesis conditions. The non-polar orthorhombic structure exhibits a subtle, irreversible transformation into the ferroelectric monoclinic-II (m-II) phase above 421 K. At a slightly higher temperature of 426 K this m-II (P21) phase reversibly transforms into a disordered, paraelectric monoclinic-I (P21/m) structure. We synthesized DIPAB in the orthorhombic structure, heated it to obtain the m-II phase and carried out a systematic study of their Raman and IR spectra. We obtained the phonon irreducible representations from factor group analysis of the orthorhombic and m-II structures based on the reported structural information. DIPAB is an organic molecular crystal, and the vibrational spectra in the intramolecular region (200-3500 cm- 1) of the two different phases are identical to each other, indicating weak inter-molecular interactions in both crystalline structures. In the low wavenumber region (10-150 cm- 1) the Raman spectra of the two phases are different due to their sensitivity to molecular environment. We also carried out first principles calculations using Gaussian 09 and CASTEP codes to analyze the vibrational frequencies. Mode assignments were facilitated by isolated molecule calculations that are also in good agreement with intramolecular vibrations, whereas CASTEP (solid state) results could explain the external modes.

  15. Fabrication of double-sided thallium bromide strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Hitomi, Keitaro, E-mail: keitaro.hitomi@qse.tohoku.ac.jp [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Nagano, Nobumichi [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Onodera, Toshiyuki [Department of Electronics and Intelligent Systems, Tohoku Institute of Technology, Sendai 982-8577 (Japan); Kim, Seong-Yun; Ito, Tatsuya; Ishii, Keizo [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2016-07-01

    Double-sided strip detectors were fabricated from thallium bromide (TlBr) crystals grown by the traveling-molten zone method using zone-purified materials. The detectors had three 3.4-mm-long strips with 1-mm widths and a surrounding electrode placed orthogonally on opposite surfaces of the crystals at approximately 6.5×6.5 mm{sup 2} in area and 5 mm in thickness. Excellent charge transport properties for both electrons and holes were observed from the TlBr crystals. The mobility-lifetime products for electrons and holes in the detector were measured to be ~3×10{sup −3} cm{sup 2}/V and ~1×10{sup −3} cm{sup 2}/V, respectively. The {sup 137}Cs spectra corresponding to the gamma-ray interaction position were obtained from the detector. An energy resolution of 3.4% of full width at half maximum for 662-keV gamma rays was obtained from one “pixel” (an intersection of the strips) of the detector at room temperature.

  16. Improved spectrometric characteristics of thallium bromide nuclear radiation detectors

    CERN Document Server

    Hitomi, K; Shoji, T; Suehiro, T; Hiratate, Y

    1999-01-01

    Thallium bromide (TlBr) is a compound semiconductor with a high atomic number and wide band gap. In this study, nuclear radiation detectors have been fabricated from the TlBr crystals. The TlBr crystals were grown by the horizontal travelling molten zone (TMZ) method using the materials purified by many pass zone refining. The crystals were characterized by measuring the resistivity, the mobility-lifetime (mu tau) product and the energy required to create an electron-hole pair (the epsilon value). Improved energy resolution has been obtained by the TlBr radiation detectors. At room temperature the full-width at half-maximum (FWHM) for the 59.5, 122 and 662 keV gamma-ray photo peak obtained from the detectors were 3.3, 8.8 and 29.5 keV, respectively. By comparing the saturated peak position of the TlBr detector with that of the CdTe detector, the epsilon value has been estimated to be about 5.85 eV for the TlBr crystal.

  17. Micellization of cetyltrimethylammonium bromide: effect of small chain Bola electrolytes.

    Science.gov (United States)

    Pan, Animesh; Sil, Pallabi; Dutta, Sounak; Das, Prasanta Kumar; Bhattacharya, Subhash Chandra; Rakshit, Animesh Kumar; Aswal, Vinod Kumar; Moulik, Satya Priya

    2014-03-20

    Sodium dicarboxylates (or Bola salts) with methylene spacers 0, 2, 4, 6, 8, and 10 were studied in aqueous solution to investigate their influence on the micellization of cetyltrimethylammonium bromide (CTAB). Since bolas with spacer length ≤12 are known not to micellize in general, the herein used sodium dicarboxylates were treated as 2:1 amphiphilic electrolytes which reduced surface tension of water (except sodium oxalate with zero spacer) without self-association. Their concentration dependent conductance was also linear without breaks. The bolas affected the micellization of CTAB but acted like salts to decrease its CMC. Their combinations did not form bilayer aggregates as found in vesicles. Nevertheless, they synergistically interacted with CTAB at the air/water interface as revealed from Rosen's thermodynamic model. Hydrodynamic radius (Rh), Zeta-potential (ζ), and electrical double layer behavior of bola interacted CTAB micelles were assessed. From SANS measurements, micelle shape, shape parameters, aggregation number (Nagg), surface charge of the bola influenced CTAB micelles were also determined. NMR study as well supported the non-mixing of bolas with the CTAB micelles. They interacted in solution like "amphiphilic electrolytes" to influence the surface and micelle forming properties of CTAB.

  18. Evaluation of Alkali Bromide Salts for Potential Pyrochemical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Prabhat K. Tripathy; Steven D. Herrmann; Guy L. Fredrickson; Tedd E. Lister; Toni Y. Gutknecht

    2013-10-01

    Transient techniques were employed to study the electrochemical behavior, reduction mechanism and transport properties of REBr3 (RE - La, Nd and Gd) in pure LiBr, LiBr-KBr (eutectic) and LiBr-KBr-CsBr (eutectic) melts. Gd(III) showed a reversible single step soluble-insoluble exchange phenomenon in LiBr melt at 973K. Although La (III), Nd(III) and Gd(III) ions showed reversible behavior in eutectic LiBr-KBr melts, these ions showed a combination of temperature dependent reversible and pseudo-reversible behavior. While both La(III) and Gd(III) showed one step reduction, the reduction of Nd(III) was observed to be a two step process. La metal could be electrodeposited from the ternary electrolyte at a temperature of 673K. Various electrochemical measurements suggest that both binary and ternary bromide melts can potentially be used to electrodeposit high purity RE metals at comparatively lower operating temperatures.

  19. Organomontmorillonites Modified with 2-Methacryloyloxy Ethyl Alkyl Dimethyl Ammonium Bromide

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-quan; WU Wen-hui

    2007-01-01

    Organomontmorillonites (organo-MMT) were synthesized by means of montmorillonites (MMT) modified with a series of 2-methacryloyloxy ethyl alkyl dimethyl ammonium bromide (MAAB) having different alkyl chain lengths as cationic surfactants through a cationic exchanging reaction, and were characterized by FTIR, TG, elemental analysis, and XRD. The microenvironment of the organic interlayer such as the orientation and arrangement of the alkyl chains of MAAB, as well as the properties of nanocomposite hydrogels, were also investigated. The amount of organic components absorbed on interlayer and the basal spacing of organo-MMT both increase with the increasing of alkyl length of MAAB. When carbon number of alkyl chain is in the region of 8 to 14, the alkyl chains between layers would adopt a disordered gauche conformation; while the carbon number is 16, an ordered all-trans conformation with a vertical orientation would be found together with the disordered gauche conformation according to the results of XRD and FTIR. Due to the difference of microenvironment of organic interlayer, the Young's moduli of the nanocomposite hydrogels increased as the alkyl chains of MAAB became longer.

  20. Accommodation coefficient of HOBr on deliquescent sodium bromide aerosol particles

    Directory of Open Access Journals (Sweden)

    M. Wachsmuth

    2002-01-01

    Full Text Available Uptake of HOBr on sea salt aerosol, sea salt brine or ice is believed to be a key process providing a source of photolabile bromine (Br2 and sustaining ozone depletion cycles in the Arctic troposphere. In the present study, uptake of HOBr on sodium bromide (NaBr aerosol particles was investigated at an extremely low HOBr concentration of 300 cm-3 using the short-lived radioactive isotopes 83-86Br. Under these conditions, at maximum one HOBr molecule was taken up per particle. The rate of uptake was clearly limited by the mass accommodation coefficient, which was calculated to be 0.6 ± 0.2. This value is a factor of 10 larger than estimates used in earlier models. The atmospheric implications are discussed using the box model "MOCCA'', showing that the increase of the accommodation coefficient of HOBr by a factor of 10 only slightly affects net ozone loss, but significantly increases chlorine release.

  1. Otilonium bromide: a selective spasmolytic for the gastrointestinal tract.

    Science.gov (United States)

    Evangelista, S

    1999-01-01

    Experimental studies have shown that otilonium bromide (OB) inhibits both baseline and chemically or physically stimulated gastrointestinal motility. The spasmolytic activity of OB in the gastrointestinal tract occurs at doses that do not affect gastric secretion or produce typical atropine-like side-effects. The mechanism of action is composite: interference with calcium ion movement from intra- and extracellular sites; blockade of calcium channels; and binding to muscarinic receptors and tachykinin neurokinin-2 receptors. Pharmacokinetic studies have shown that OB accumulates in the lower intestine and has poor systemic absorption. Clinical studies have confirmed OB as a potent spasmolytic drug with a good tolerability profile. Studies in patients with irritable bowel syndrome demonstrated OB to be superior to placebo and reference drugs in parameters such as pain, abdominal distension and motility. The composite and local mechanism of OB action reduces hypermotility and modulates visceral sensation: factors thought to be responsible for pain improvement recorded in clinical trials. The compound is marketed worldwide and no serious adverse events have been reported as yet, confirming its excellent tolerability.

  2. Structural and electronic properties of Diisopropylammonium bromide molecular ferroelectric crystal

    Science.gov (United States)

    Alsaad, A.; Qattan, I. A.; Ahmad, A. A.; Al-Aqtash, N.; Sabirianov, R. F.

    2015-10-01

    We report the results of ab-initio calculations based on Generalized Gradient Approximation (GGA) and hybrid functional (HSE06) of electronic band structure, density of states and partial density of states to get a deep insight into structural and electronic properties of P21 ferroelectric phase of Diisopropylammonium Bromide molecular crystal (DIPAB). We found that the optical band gap of the polar phase of DIPAB is ∼ 5 eV confirming it as a good dielectric. Examination of the density of states and partial density of states reveal that the valence band maximum is mainly composed of bromine 4p orbitals and the conduction band minimum is dominated by carbon 2p, carbon 2s, and nitrogen 2s orbitals. A unique aspect of P21 ferroelectric phase is the permanent dipole within the material. We found that P21 DIPAB has a spontaneous polarization of 22.64 consistent with recent findings which make it good candidate for the creation of ferroelectric tunneling junctions (FTJs) which have the potential to be used as memory devices.

  3. Bioreactors for removing methyl bromide following contained fumigations

    Science.gov (United States)

    Miller, L.G.; Baesman, S.M.; Oremland, R.S.

    2003-01-01

    Use of methyl bromide (MeBr) as a quarantine, commodity, or structural fumigant is under scrutiny because its release to the atmosphere contributes to the depletion of stratospheric ozone. A closed-system bioreactor consisting of 0.5 L of a growing culture of a previously described bacterium, strain IMB-1, removed MeBr (> 110 ??mol L-1) from recirculating air. Strain IMB-1 grew slowly to high cell densities in the bioreactor using MeBr as its sole carbon and energy source. Bacterial oxidation of MeBr produced CO2 and hydrobromic acid (HBr), which required continuous neutralization with NaOH for the system to operate effectively. Strain IMB-1 was capable of sustained oxidation of large amounts of MeBr (170 mmol in 46 d). In an open-system bioreactor (10-L fermenter), strain IMB-1 oxidized a continuous supply of MeBr (220 ??mol L-1 in air). Growth was continuous, and 0.5 mol of MeBr was removed from the air supply in 14 d. The specific rate of MeBr oxidation was 7 ?? 10-16 mol cell-1 h-1. Bioreactors such as these can therefore be used to remove large quantities of contaminant MeBr, which opens the possibility of biodegradation as a practical means for its disposal.

  4. Chloride, bromide and iodide scintillators with europium doping

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2014-08-26

    A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX.sub.3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa.sub.1-yEu.sub.yI.sub.3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA.sub.1-yEu.sub.yX.sub.3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0.ltoreq.y.ltoreq.1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

  5. Delayed remyelination in rat spinal cord following ethidium bromide injection.

    Science.gov (United States)

    Graça, D L; Blakemore, W F

    1986-01-01

    Areas of demyelination were produced by injecting ethidium bromide into the white matter of the lumbar spinal cord of rats. There was variation in the nature of the process of demyelination and a difference in the speed with which Schwann cells remyelinated the demyelinated axons. In some lesions, or areas within lesions, myelin debris was rapidly processed by macrophages and axons were rapidly remyelinated by Schwann cells, while in other lesions of similar duration, or in areas within the same lesion, the myelin was transformed into lattices of membranous profiles which persisted around axons for long periods of time. In the lesions containing such myelin derived membranes, there were few macrophages and remyelination by Schwann cells was delayed compared to that seen in the more rapidly resolving lesions. It was concluded that the slow resolution of some lesions resulted from the delay between intoxication and cell disintegration (7-10 days) which meant that the cell responses to demyelination took place in a glial free area which could not support cell movement needed for removal of myelin debris and remyelination. This study indicates that the tempo and results of demyelination can be altered by the cellular events which accompany degeneration of oligodendrocytes.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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. Efficient loading of primary alcohols onto a solid phase using a trityl bromide linker

    DEFF Research Database (Denmark)

    Crestey, François; Ottesen, Lars Korsgaard; Jaroszewski, Jerzy Witold

    2008-01-01

    The Letter describes an improved, rapid and mild strategy for the loading of primary alcohols onto a polystyrene trityl resin via a highly reactive trityl bromide linker. This protocol facilitates an efficient resin loading even of acid-sensitive or heat-labile alcohols, which otherwise require...... of a sensitive alcohol containing an activated aziridine functionality, the use of the trityl bromide linker proved superior to a recently described silver triflate-assisted trityl chloride resin-based procedure....

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

    Science.gov (United States)

    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.

  10. Tribromoisocyanuric acid/triphenylphosphine: a new system for conversion of alcohols into alkyl bromides

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Vitor S.C. de; Mattos, Marcio C.S. de, E-mail: mmattos@iq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Quimica. Departamento de Quimica Organica

    2014-05-15

    An efficient and facile method has been developed for the conversion of alcohols into alkyl bromides under neutral conditions using tribromoisocyanuric acid and triphenylphosphine (molar ratio 1.0:0.7:2.0, alcohol/tribromoisocyanuric acid/triphenylphosphine) in dichloromethane at room temperature. This method can be applied for the conversion of primary, secondary, benzilic and allylic alcohols, and their corresponding bromides are obtained in 67-82 % yield. Tertiary alcohols do not react under these conditions. (author)

  11. Interaction of removal Ethidium Bromide with Carbon Nanotube: Equilibrium and Isotherm studies

    OpenAIRE

    Moradi, Omid; Norouzi, Mehdi; Fakhri, Ali; Naddafi, Kazem

    2014-01-01

    Drinking water resources may be contaminated with Ethidium Bromide (EtBr) which is commonly used in molecular biology laboratories for DNA identification in electrophoresis. Carbon nanotubes are expected to play an important role in sensing, pollution treatment and separation techniques. In this study adsorption of Ethidium Bromide on single-walled carbon nanotubes (SWCNTs) and carboxylate group functionalized single-walled carbon nanotube (SWCNT-COOH) surfaces have been investigated by UV–vi...

  12. Control of insects with fumigants at low temperatures: toxicity of mixtures of methyl bromide and acrylonitrile to three species of insects

    Energy Technology Data Exchange (ETDEWEB)

    Bond, E.J.; Buckland, C.T.

    1976-12-15

    Acrylonitrile can be mixed with methyl bromide to increase toxicity so that the quantity of methyl bromide required for control of Sitophilus granarius (L.), Tenebrio molitor L., and Tribolium confusum Jacquelin duval is reduced by one half. Mixtures of methyl bromide and acrylonitrile are considerably more effective at low temperatures than methyl bromide alone.

  13. [Otilonium bromide-diazepam in the treatment of the irritable colon. A controlled study versus otilonium bromide].

    Science.gov (United States)

    Mollica, G; Manno, G

    1992-08-01

    Octylonium bromide (OB) is a drug with spasmolytic properties acting selectively on the smooth muscle of the gastrointestinal tract by interfering with calcium mobilization from extra- and intra-cellular deposits. The etiopathogenetic implications of a psychosomatic nature of the irritable bowel syndrome amply justify the use of a spasmolytic (OB) with a benzodiazepine. In our study, we compared the combination OB + DZ (20 mg + 2 mg) T.I.D. versus OB alone (20 mg) in 30 patients suffering from irritable bowel syndrome. The double-blind study lasting 3 weeks was aimed at evaluating gastrointestinal symptoms (bowel motions, aspect of faeces, abdominal pain, pre-evacuation pain, bloating) during the three days preceding the study and during the last five days of treatment, as well as the anxiogenic situation as assessed by the STAI scale (State Tract Anxiety Inventory) before and at the end of the treatment period. The results obtained showed that both treatments considerably reduced gastrointestinal symptoms even though OB alone did not appear to be equally effective and the anxiety component was significantly reduced only by treatment with the combination. The absence of side effects and the perfect tolerability of both treatments showed the OB + D combination T.I.D. to be the treatment of choice for patients suffering from irritable bowel syndrome.

  14. Otilonium bromide enhances sensory thresholds of volume and pressure in patients with irritable bowel syndrome.

    Science.gov (United States)

    Czimmer, J; Süto, G; Király, A; Mózsik, G

    2001-01-01

    Visceral hyperalgesia has been suggested to play a role in the development of symptoms presented by irritable bowel syndrome patients. Otilonium bromide was developed to block smooth muscle Ca release to control cramping pain of these patients. to determine whether otilonium bromide can influence sensory thresholds of patients suffering from irritable bowel syndrome. 15 patients with Rome-II positive IBS were tested by Synectics Visceral Stimulator Barostat using rapid phasic distension (870 ml/min). The sensory threshold for first sensation, stool, pain and maximum tolerable volume and pressure were measured. All of the parameters were tested before and 1 week after the initiation of otilonium bromide (Spasmomen, Berlin Chemie, 3x40 mg) therapy. The perceptual thresholds for first sensation, stool, pain and maximum tolerable distention were, 8.8+/-1.7 Hgmm, 19.2+/-2.1 Hgmm, 26.3+/-2.8 Hgmm, 28.7+/-2.8 Hgmm for pressure, 90+/-21 ml, 145+/-28 ml, 208+/-25 ml, 213+/-28 ml for volume, before treatment, respectively. Otilonium bromide treatment did not influence the thresholds for first sensation and stool, 7.4+/-1.4 Hgmm, 20.7+/-4.6 Hgmm and 83+/-21 ml, 178+/-35.8 ml, respectively. The pressure threshold of pain was significantly higher 1 week after treatment (26.3+/-2.8 Hgmm vs. 29.1+/-5.5 Hgmm, Potilonium bromide treatment. These data suggest that otilonium bromide enhances sensory thresholds to recto-sigmoideal distention.

  15. Otilonium bromide in irritable bowel syndrome: a double-blind, placebo-controlled, 15-week study.

    Science.gov (United States)

    Battaglia, G; Morselli-Labate, A M; Camarri, E; Francavilla, A; De Marco, F; Mastropaolo, G; Naccarato, R

    1998-10-01

    To evaluate the efficacy of otilonium bromide, a spasmolytic agent, in the treatment of irritable bowel syndrome using modern and validated diagnostic criteria. Three hundred and seventy-eight patients with irritable bowel syndrome were enrolled in the study. At entry, endoscopy/barium enema, clinical examination and laboratory tests were used to rule out organic diseases. After a 2-week placebo run-in, 325 patients were randomly assigned to receive either otilonium bromide 40 mg t.d.s. or placebo for 15 weeks. Abdominal pain, abdominal distension and disturbed defecation were scored at the beginning of the study and every 5 weeks. A global determination of well-being by visual analogue scale and the tenderness of the sigmoid colon were also scored. The reduction in the number of abdominal pain episodes was significantly higher (P otilonium bromide patients (55.3%) than in those taking placebo (39.9%) as was the severity of abdominal distension (42.0%, vs. 30.2%; P otilonium bromide. The investigators' global positive assessment was in favour of otilonium bromide (65.2%) compared with placebo (49.6%) (P Otilonium bromide may represent an effective treatment for irritable bowel syndrome because it reduces its predominant symptom (abdominal pain/ discomfort) more than placebo does.

  16. Electrochemical Recognition of Metalloproteins by Bromide-modified Silver Electrode - A New Method

    Directory of Open Access Journals (Sweden)

    Abbas Ali Rostami

    2007-07-01

    Full Text Available A bromide–modified silver electrode is reported, in the present study, to catalyzethe redox reactions of metalloproteins. This study describes that the bromide ions showvery good redox behavior with silver electrode. The cathodic and anodic peak potentialswere related to the concentration of bromide ions involved in making bromide-modifiedsilver electrode. The electrode reaction in the bromine solution was a diffusion-controlledprocess. Positive potential shift of the bromide ions was seen when different proteins wereadded to the solution using a silver electrode. New cathodic and anodic peaks wereobserved at different potential ranges for myoglobin, cytochrome c and catalase. A linearlyincreasing cathodic peak current of bromide ions was seen when the concentration ofsuperoxide dismutase was increased in the test solution. However, no change for albuminwas observed when its concentration was increased in the test solution. Present data provesour methodology as an easy-to-use analysis for comparing the redox potentials of differentmetalloproteins and differentiating the metallo- from non-metalloproteins. In this study, weintroduced an interesting method for bio-electrochemical analyses.

  17. Effect of ferric and bromide ions on the formation and speciation of disinfection byproducts during chlorination

    Institute of Scientific and Technical Information of China (English)

    Shaogang Liu; Zhiliang Zhu; Yanling Qiu; Jianfu Zhao

    2011-01-01

    The effects of ferric ion, pH, and bromide on the formation and distribution of disinfection byproducts (DBPs) during chlorination were studied. Two raw water samples from Huangpu River and Yangtze River, two typical drinking water sources of Shanghai, were used for the investigation. Compared with the samples from Huangpu River, the raw water samples from Yangtze River had lower content of total organic carbon (TOC) and ferric ions, but higher bromide concentrations. Under controlled chlorination conditions,four trihalomethanes (THMs), nine haloacetic acids (HAAs), total organic halogen (TOX) and its halogen species fractions, including total organic chlorine (TOC1) and total organic bromide (TOBr), were determined. The results showed that co-existent ferric and bromide ions significantly promoted the formation of total THMs and HAAs for both raw water samples. Higher concentration of bromide ions significantly changed the speciation of the formed THMs and HAAs. There was an obvious shift to brominated species,which might result in a more adverse influence on the safety of drinking water. The results also indicated that high levels of bromide ions in raw water samples produced higher percentages of unknown TOBr.

  18. Effect of ferric and bromide ions on the formation and speciation of disinfection byproducts during chlorination.

    Science.gov (United States)

    Liu, Shaogang; Zhu, Zhiliang; Qiu, Yanling; Zhao, Jianfu

    2011-01-01

    The effects of ferric ion, pH, and bromide on the formation and distribution of disinfection byproducts (DBPs) during chlorination were studied. Two raw water samples from Huangpu River and Yangtze River, two typical drinking water sources of Shanghai, were used for the investigation. Compared with the samples from Huangpu River, the raw water samples from Yangtze River had lower content of total organic carbon (TOC) and ferric ions, but higher bromide concentrations. Under controlled chlorination conditions, four trihalomethanes (THMs), nine haloacetic acids (HAAs), total organic halogen (TOX) and its halogen species fractions, including total organic chlorine (TOC1) and total organic bromide (TOBr), were determined. The results showed that co-existent ferric and bromide ions significantly promoted the formation of total THMs and HAAs for both raw water samples. Higher concentration of bromide ions significantly changed the speciation of the formed THMs and HAAs. There was an obvious shift to brominated species, which might result in a more adverse influence on the safety of drinking water. The results also indicated that high levels of bromide ions in raw water samples produced higher percentages of unknown TOBr.

  19. A dysprosium-based metal-organic framework: Synthesis, characterization, crystal structure and interaction with calf thymus-DNA and bovine serum albumin

    Indian Academy of Sciences (India)

    Biplab Mondal; Buddhadeb Sen; Ennio Zangrando; Pabitra Chattopadhyay

    2014-07-01

    A dysprosium-based metallo-organic framework (MOF) containing calcium ions formulated as {Dy(pyda)3Ca1.5(H2O)6} · 5.5H2O (1) (H2pyda = pyridine-2,6-dicarboxylic acid) was solvothermally synthesized in ethanolic medium and characterized by physico-chemical and spectroscopic tools. A detailed structural analysis of the solid state structure of 1 by single crystal X-ray diffraction study showed a tricapped trigonal prism geometry for lanthanide in the [Dy(pyda)3]3− fragment. The mode of interaction of 1 with calf thymus- DNA and with protein bovine serum albumin (BSA) was investigated by using absorption and emission spectroscopic tools. The apparent association constant of complex 1 with CT-DNA was deduced from an absorption spectral study (b = 4.08 × 104 M-1). Spectral and viscosity measurements indicated a groove-binding mode of 1 with CT-DNA, and from spectroscopic study the formation of a metal complex-BSA adduct was assumed to be the result of the interaction of 1 with BSA.

  20. Dual-mode T1 and T2 magnetic resonance imaging contrast agent based on ultrasmall mixed gadolinium-dysprosium oxide nanoparticles: synthesis, characterization, and in vivo application

    Science.gov (United States)

    Tegafaw, Tirusew; Xu, Wenlong; Wasi Ahmad, Md; Baeck, Jong Su; Chang, Yongmin; Bae, Ji Eun; Chae, Kwon Seok; Kim, Tae Jeong; Lee, Gang Ho

    2015-09-01

    A new type of dual-mode T1 and T2 magnetic resonance imaging (MRI) contrast agent based on mixed lanthanide oxide nanoparticles was synthesized. Gd3+ (8S7/2) plays an important role in T1 MRI contrast agents because of its large electron spin magnetic moment resulting from its seven unpaired 4f-electrons, and Dy3+ (6H15/2) has the potential to be used in T2 MRI contrast agents because of its very large total electron magnetic moment: among lanthanide oxide nanoparticles, Dy2O3 nanoparticles have the largest magnetic moments at room temperature. Using these properties of Gd3+ and Dy3+ and their oxide nanoparticles, ultrasmall mixed gadolinium-dysprosium oxide (GDO) nanoparticles were synthesized and their potential to act as a dual-mode T1 and T2 MRI contrast agent was investigated in vitro and in vivo. The D-glucuronic acid coated GDO nanoparticles (davg = 1.0 nm) showed large r1 and r2 values (r2/r1 ≈ 6.6) and as a result clear dose-dependent contrast enhancements in R1 and R2 map images. Finally, the dual-mode imaging capability of the nanoparticles was confirmed by obtaining in vivo T1 and T2 MR images.

  1. Experimental and molecular dynamics studies of dysprosium(III) salt solutions for a better representation of the microscopic features used within the binding mean spherical approximation theory.

    Science.gov (United States)

    Ruas, Alexandre; Guilbaud, Philippe; Den Auwer, Christophe; Moulin, Christophe; Simonin, Jean-Pierre; Turq, Pierre; Moisy, Philippe

    2006-10-19

    This work is aimed at a predictive description of the thermodynamic properties of actinide(III) salt solutions at high concentration and 25 degrees C. A new solution of the binding mean spherical approximation (BIMSA) theory, based on the Wertheim formalism, for taking into account 1:1 and also 1:2 complex formation, is used to reproduce, from a simple procedure, experimental osmotic coefficient variation with concentration for three binary salt solutions of the same lanthanide(III) cation: dysprosium(III) perchlorate, nitrate, and chloride. The relevance of the fitted parameters is discussed, and their values are compared with available literature values. UV-vis/near-IR, time-resolved laser-induced fluorescence spectroscopy experiments, and molecular dynamics (MD) calculations were conducted for dilute to concentrated solutions (ca. 3 mol.kg-1) for a study of the microscopic behavior of DyCl3 binary solutions. Coupling MD calculations and extended X-ray absorption fine structure led to the determination of reliable distances. The MD results were used for a discussion of the parameters used in the BIMSA.

  2. Experimental and molecular dynamics studies of dysprosium(III) salt solutions for a better representation of the microscopic features used within the binding mean spherical approximation theory

    Energy Technology Data Exchange (ETDEWEB)

    Ruas, Alexandre; Guilbaud, Philippe; Den Auwer, Christophe; Moulin, Christophe; Simonin, Jean-Pierre; Turq, Pierre; Moisy, Philippe [DEN/DRCP/SCPS, CEA-Valrho Marcoule, BP 17171, 30207 Bagnols-sur-Ceze Cedex, DEN/DPC/SECR/LSRM, CEA-Saclay, Bat 391, BP 91191 Gif sur Yvette, Cedex (France); Laboratoire LI2C (UMR 7612), Universite Pierre et Marie Curie-Paris 6, Boite No. 51, 4 Place Jussieu, 75252 Paris Cedex 05 (France)

    2006-07-01

    This work is aimed at a predictive description of the thermodynamic properties of actinide (III) salt solutions at high concentration and 25 deg. C. A new solution of the binding mean spherical approximation (BIMSA) theory, based on the Wertheim formalism, for taking into account 1: 1 and also 1: 2 complex formation, is used to reproduce, from a simple procedure, experimental osmotic coefficient variation with concentration for three binary salt solutions of the same lanthanide (III) cation: dysprosium (III) perchlorate, nitrate, and chloride. The relevance of the fitted parameters is discussed, and their values are compared with available literature values. UV-vis/near-IR, time-resolved laser-induced fluorescence spectroscopy experiments, and molecular dynamics (MD) calculations were conducted for dilute to concentrated solutions (ca. 3 mol, kg{sup -1}) for a study of the microscopic behavior of DyCl{sub 3} binary solutions. Coupling MD calculations and extended X-ray absorption fine structure led to the determination of reliable distances. The MD results were used for a discussion of the parameters used in the BIMSA. (authors)

  3. Elucidation of Dual Magnetic Relaxation Processes in Dinuclear Dysprosium(III) Phthalocyaninato Triple-Decker Single-Molecule Magnets Depending on the Octacoordination Geometry.

    Science.gov (United States)

    Katoh, Keiichi; Aizawa, Yu; Morita, Takaumi; Breedlove, Brian K; Yamashita, Masahiro

    2017-08-07

    When applying single-molecule magnets (SMMs) to spintronic devices, control of the quantum tunneling of the magnetization (QTM) as well as a spin-lattice interactions are important. Attempts have been made to use not only coordination geometry but also magnetic interactions between SMMs as an exchange bias. In this manuscript, dinuclear dysprosium(III) (Dy(III) ) SMMs with the same octacoordination geometry undergo dual magnetic relaxation processes at low temperature. In the dinuclear Dy(III) phthalocyaninato (Pc(2-) ) triple-decker type complex [(Pc)Dy(ooPc)Dy(Pc)] (1) (ooPc(2-) =2,3,9,10,16,17,23,24-octakis(octyloxy)phthalocyaninato) with a square-antiprismatic (SAP) geometry, the ground state is divided by the Zeeman effect, and level intersection occurs when a magnetic field is applied. Due to the ground state properties of 1, since the Zeeman diagram where the levels intersect in an Hdc of 2500 Oe, two kinds of QTM and direct processes occur. However, dinuclear Dy(III) -Pc systems with C4 geometry, which have a twist angle (ϕ) of less than 45° do not undergo dual magnetic relaxation processes. From magnetic field and temperature dependences, the dual magnetic relaxation processes were clarified. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Annealing behaviour and crystal structure of RF-sputtered Bi-substituted dysprosium iron-garnet films having excess co-sputtered Bi-oxide content

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, M; Nur-E-Alam, M; Alameh, K [Electron Science Research Institute, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027 (Australia); Premchander, P; Lee, Y T [Department of Information and Communications, Gwangju Institute of Science and Technology (GIST), Gwangju, 500-712 (Korea, Republic of); Kotov, V A [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 11 Mohovaya St, Moscow, 125009 (Russian Federation); Lee, Y P, E-mail: m.vasiliev@ecu.edu.au [Quantum Photonic Science Research Center, Department of Physics, Hanyang University, 133-791 (Korea, Republic of)

    2011-02-23

    We investigate the magneto-optic properties, crystal structure and annealing behaviour of nano-composite media with record-high magneto-optic quality exceeding the levels reported so far in sputtered iron-garnet films. Bi-substituted dysprosium-gallium iron-garnet films having excess bismuth oxide content are deposited using RF co-sputtering, and a range of garnet materials are crystallized using conventional oven-annealing processes. We report, for the first time ever, the results of optimization of thermal processing regimes for various high-performance magneto-optic iron-garnet compositions synthesized and describe the evolution of the optical and magneto-optical properties of garnet-Bi-oxide composite-material films occurring during the annealing processes. The crystallization temperature boundaries of the system (BiDy){sub 3}(FeGa){sub 5}O{sub 12} : Bi{sub 2}O{sub 3} are presented. We also report the results of x-ray diffraction and energy-dispersive x-ray spectroscopy studies of this recently developed class of high-performance magneto-optic composites. Our hypothesis of iron oxides being the cause of excess optical absorption in sputtered Bi-iron-garnet films is confirmed experimentally.

  5. Silica nanoparticles separation from water: aggregation by cetyltrimethylammonium bromide (CTAB).

    Science.gov (United States)

    Liu, Y; Tourbin, M; Lachaize, S; Guiraud, P

    2013-07-01

    Nanoparticles will inevitably be found in industrial and domestic wastes in the near future and as a consequence soon in water resources. Due to their ultra-small size, nanoparticles may not only have new hazards for environment and human health, but also cause low separation efficiency by classical water treatments processes. Thus, it would be an important challenge to develop a specific treatment with suitable additives for recovery of nanoparticles from waters. For this propose, this paper presents aggregation of silica nanoparticles (Klebosol 30R50 (75nm) and 30R25 (30nm)) by cationic surfactant cetyltrimethylammonium bromide (CTAB). Different mechanisms such as charge neutralization, "depletion flocculation" or "volume-restriction", and "hydrophobic effect" between hydrocarbon tails of CTAB have been proposed to explicate aggregation results. One important finding is that for different volume concentrations between 0.05% and 0.51% of 30R50 suspensions, the same critical coagulation concentration was observed at CTAB=0.1mM, suggesting the optimized quantity of CTAB during the separation process for nanoparticles of about 75nm. Furthermore, very small quantities of CTAB (0.01mM) can make 30R25 nanosilica aggregated due to the "hydrophobic effect". It is then possible to minimize the sludge and allow the separation process as "greener" as possible by studying this case. It has also shown that aggregation mechanisms can be different for very small particles so that a special attention has to be paid to the treatment of nanoparticles contained in water and wastewaters.

  6. Predicting bromide incorporation in a chlorinated indoor swimming pool.

    Science.gov (United States)

    Chowdhury, Shakhawat; Mazumder, Abu Jafar; Husain, Tahir

    2016-06-01

    The water in and air above swimming pools often contain high levels of disinfection byproducts (DBPs) due to chemical reactions between chlorine- or bromine-based disinfectants and organic/inorganic matter in the source water and released from swimmers. Exposure to these DBPs, though inevitable, can pose health threats to humans. In this study, DBPs in tap water (S1), and water from a chlorinated indoor swimming pool before (S2) and after swimming (S3) were measured. The brominated species constituted the majority of DBPs formed in S1, S2, and S3. Trihalomethanes (THMs) in S3 was 6.9 (range 2.9-11.1) and 1.4 (range 0.52-2.9) times those in S1 and S2, respectively; and the haloacetic acids (HAAs) in S3 was 4.2 (range 2.5-7.5) and 1.2 (range 0.6-2.6) times those in S1 and S2, respectively. The mean THMs in air above the swimming pool before (S2-A) and after swimming (S3-A) were 72.2 and 93.0 μg/m(3), respectively, and their ranges were 36.3-105.8 and 44.1-133.6 μg/m(3), respectively. The average percentages of bromide incorporation (BI) into THMs in S1, S2, and S3 were 3.0, 9.3, and 10.6 %, respectively; and the BI into HAAs in S1, S2, and S3 were 6.6, 12.0, and 12.2 %, respectively. Several models were trained for predicting the BI into THMs and HAAs. The results indicate that additional information is required to develop predictive models for BI in swimming pools.

  7. Otilonium bromide as spasmolytic during endoscopic retrograde cholangiopancreatography.

    Science.gov (United States)

    Karahan, Ömer; Sevinç, Barış; Okuş, Ahmet; Ay, Serden; Aksoy, Nergis

    2015-08-01

    Endoscopic retrograde cholangiopancreatography (ERCP) is commonly used in both the diagnosis and the treatment of biliary and pancreatic disorders. The aim of this study is to evaluate the effects of OB usage during ERCP on duodenal motility, the tolerability of the procedure (by patients) and the difficulty of the procedure (by the endoscopist). The study was conducted in Konya Training and Research Hospital General Surgery Endoscopy Unit in randomized prospective pattern. The patients were divided into the two groups as spasmolytic and control groups. The procedure was performed under topical anesthesia and sedation. There were 100 cases included into the study (50 cases in each group). The mean duodenal motility score was found to be 1.9 ± 0.5 in the study group and 3 ± 0.6 in the control group. In the study group, the tolerability of the procedure score by the endoscopist was moderate in 16 % and well/very well in 78 % of the cases. On the other hand, in the control group, the scores were poor in 21 %, moderate in 71 %, and well/very well in 24 % of the cases. In terms of patient satisfaction, in study group 42 % of the cases reported the procedure as moderate and 58 % reported as well/very well. However, in the control group 16 % of the cases reported the procedure as poor, 58 % moderate, and 26 % as well/very well. Otilonium bromide is a safe agent with low side effects. It can be used before the ERCP procedure to decrease the duodenal motility. It eases the procedure, moreover, it increases the patients' satisfaction.

  8. Bacterial oxidation of methyl bromide in fumigated agricultural soils

    Science.gov (United States)

    Miller, L.G.; Connell, T.L.; Guidetti, J.R.; Oremland, R.S.

    1997-01-01

    The oxidation of [14C]methyl bromide ([14C]MeBr) to 14CO2 was measured in field experiments with soils collected from two strawberry plots fumigated with mixtures of MeBr and chloropicrin (CCI3NO2). Although these fumigants are considered potent biocides, we found that the highest rates of MeBr oxidation occurred 1 to 2 days after injection when the fields were tarped, rather than before or several days after injection. No oxidation of MeBr occurred in heat-killed soils, indicating that microbes were the causative agents of the oxidation. Degradation of MeBr by chemical and/or biological processes accounted for 20 to 50% of the loss of MeBr during fumigation, with evasion to the atmosphere inferred to comprise the remainder. In laboratory incubations, complete removal of [14C]MeBr occurred within a few days, with 47 to 67% of the added MeBr oxidized to 14CO2 and the remainder of counts associated with the solid phase. Chloropicrin inhibited the oxidation of MeBr, implying that use of this substance constrains the extent of microbial degradation of MeBr during fumigation. Oxidation was by direct bacterial attack of MeBr and not of methanol, a product of the chemical hydrolysis of MeBr. Neither nitrifying nor methane-oxidizing bacteria were sufficiently active in these soils to account for the observed oxidation of MeBr, nor could the microbial degradation of MeBr be linked to cooxidation with exogenously supplied electron donors. However, repeated addition of MeBr to live soils resulted in higher rates of its removal, suggesting that soil bacteria used MeBr as an electron donor for growth. To support this interpretation, we isolated a gram-negative, aerobic bacterium from these soils which grew with MeBr as a sole source of carbon and energy.

  9. Eudragit RS PO nanoparticles for sustained release of pyridostigmine bromide

    Energy Technology Data Exchange (ETDEWEB)

    Hoobakht, Fatemeh; Ganji, Fariba, E-mail: fganji@modares.ac.ir; Vasheghani-Farahani, Ebrahim [Tarbiat Modares University, Biomedical Engineering Group, Chemical Engineering Department (Iran, Islamic Republic of); Mousavi, Seyyed Mohammad [Tarbiat Modares University, Biotechnology Group, Chemical Engineering Department (Iran, Islamic Republic of)

    2013-09-15

    Pyridostigmine bromide (PB) is an inhibitor of cholinesterase, which is used in the treatment of myasthenia gravis and administered for protection against exposure to toxic nerve agents. Tests were done to investigate prolonging the half-life of PB and improving its release behavior. PB was loaded in nanoparticles (NPs) of Eudragit RS PO (Eu-RS) prepared using the technique of quasi emulsion solvent diffusion. Variables of output power of the sonicator, bath temperature and mixing time, were chosen as the optimization factors to obtain the minimum sized NPs. In addition, emulsions were tested at different ratios of drug-to-polymer by dynamic light scattering to determine size and zeta potential of NPs. UV-spectroscopy was used to determine PB content of the NPs. Drug-loaded NPs were characterized by scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectra. Results determined that mixing time had a significant impact on the size of Eu-RS NPs, but power output of sonicator and bath temperature had no significant effect. The particle size obtained at the optimum condition (power output of 70 W, bath temperature of 33 Degree-Sign C, and mixing time of 7 min) was less than 200 nm (optimum sizes were 138.9 and 179.5 nm for Eu-RS and PB-loaded Eu-RS NPs, respectively). The optimum PB-loaded Eu-RS NPs at the PB to Eu-RS weight ratio of 1-4 and 20 % of loaded PB released from the nanocarriers within 100 h.

  10. A combined solid-state NMR and X-ray crystallography study of the bromide ion environments in triphenylphosphonium bromides.

    Science.gov (United States)

    Burgess, Kevin M N; Korobkov, Ilia; Bryce, David L

    2012-04-27

    Multinuclear ((31)P and (79/81)Br), multifield (9.4, 11.75, and 21.1 T) solid-state nuclear magnetic resonance experiments are performed for seven phosphonium bromides bearing the triphenylphosphonium cation, a molecular scaffold found in many applications in chemistry. This is undertaken to fully characterise their bromine electric field gradient (EFG) tensors, as well as the chemical shift (CS) tensors of both the halogen and the phosphorus nuclei, providing a rare and novel insight into the local electronic environments surrounding them. New crystal structures, obtained from single-crystal X-ray diffraction, are reported for six compounds to aid in the interpretation of the NMR data. Among them is a new structure of BrPPh(4), because the previously reported one was inconsistent with our magnetic resonance data, thereby demonstrating how NMR data of non-standard nuclei can correct or improve X-ray diffraction data. Our results indicate that, despite sizable quadrupolar interactions, (79/81)Br magnetic resonance spectroscopy is a powerful characterisation tool that allows for the differentiation between chemically similar bromine sites, as shown through the range in the characteristic NMR parameters. (35/37)Cl solid-state NMR data, obtained for an analogous phosphonium chloride sample, provide insight into the relationship between unit cell volume, nuclear quadrupolar coupling constants, and Sternheimer antishielding factors. The experimental findings are complemented by gauge-including projector-augmented wave (GIPAW) DFT calculations, which substantiate our experimentally determined strong dependence of the largest component of the bromine CS tensor, δ(11), on the shortest Br-P distance in the crystal structure, a finding that has possible application in the field of NMR crystallography. This trend is explained in terms of Ramsey's theory on paramagnetic shielding. Overall, this work demonstrates how careful NMR studies of underexploited exotic nuclides, such

  11. Once-daily glycopyrronium bromide (Seebri Breezhaler(®)) for the treatment of chronic obstructive pulmonary disease (COPD)

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli

    2015-01-01

    glycopyrronium bromide (Seebri Breezhaler®) is a well-tolerated long-acting anti-muscarinic agent (LAMA) with a fast onset of action. In patients with moderate to severe COPD, glycopyrronium bromide has clinically important effects on level of FEV1, use of relief medication, day-time dyspnea scores, and probably...... also on health status. Furthermore, glycopyrronium bromide also has beneficial effects on dynamic hyperinflation and, probably by that, exercise tolerance. Glycopyrronium bromide has been shown to reduce the rate of exacerbations in patients with moderate to severe COPD, although as a secondary outcome...... only. EXPERT OPINION: Once-daily inhaled glycopyrronium bromide has positive impact on important COPD outcomes, comparable to the effects of other marketed LAMAs. Once-daily administration may improve adherence, and glycopyrronium bromide has the potential for a role in the future management of COPD...

  12. Global use structures of the magnetic materials neodymium and dysprosium. A scenario-based analysis of the effect of the diffusion of electromobility on the demand for rare earths; Globale Verwendungsstrukturen der Magnetwerkstoffe Neodym und Dysprosium. Eine szenariobasierte Analyse der Auswirkung der Diffusion der Elektromobilitaet auf den Bedarf an Seltenen Erden

    Energy Technology Data Exchange (ETDEWEB)

    Gloeser-Chahoud, Simon; Kuehn, Andre; Tercero Espinoza, Luis

    2016-06-15

    Neodymium-iron-boron magnets (NdFeB) have experienced a significant demand as the most powerful permanent magnet in recent years, especially for the manufacture of compact electric servomotors with high efficiency and high power density, especially for mobile applications in hybrid traction motors and electric vehicles or for electric bikes. However, NdFeB magnets are also increasingly being used in general mechanical engineering (conveying and pumping systems, tools, air conditioning systems, lift motors, etc.), in the small electric motors of conventional passenger cars or in the generators of large wind power plants with permanent magnetic direct drive. Nevertheless, there is still high uncertainty in the use structures of NdFeB magnets and the contained rare earth elements neodymium and dysprosium. An effective instrument for increasing the market transparency and the understanding of complex anthropogenic material cycles is the dynamic material flow modeling. In the present work paper, this instrument is used for an in-depth analysis of the use structures of NdFeB magnets and the contained rare earths on a global scale. The dynamic modeling of product usage cycles reveals today's usage structures and quantifies future magnetic quantities in obsolete product flows. It could be shown that the magnets in today's scrap volume are mainly contained in obsolete electronics applications such as hard disks (HDD), CD and DVD drives, which makes the recycling hardly seem to be economical due to the small magnets and the high material spread, but in the foreseeable future with larger magnetic quantities from synchronous servomotors and generators can be expected, which significantly increases the recycling potential. In a further step, the effect of the diffusion of alternative drives in the automotive market on the dysprosium requirement is analyzed using a system dynamics model and possible adaptation mechanisms in the form of different substitution effects in

  13. Magnetic behavior of manganese bromide hydrates including deuteration effects

    Energy Technology Data Exchange (ETDEWEB)

    DeFotis, G.C., E-mail: gxdefo@wm.edu [Chemistry Department, College of William & Mary, Williamsburg, VA 23187 (United States); Van Dongen, M.J.; Hampton, A.S.; Komatsu, C.H.; Pothen, J.M.; Trowell, K.T.; Havas, K.C.; Chan, D.G.; Reed, Z.D. [Chemistry Department, College of William & Mary, Williamsburg, VA 23187 (United States); Hays, K.; Wagner, M.J. [Chemistry Department, George Washington University, Washington, D.C. 20052 (United States)

    2016-07-15

    The magnetic properties of previously unexamined MnBr{sub 2}·2H{sub 2}O, MnBr{sub 2}·H{sub 2}O, MnBr{sub 2}·2D{sub 2}O and MnBr{sub 2}·D{sub 2}O are studied. Curie–Weiss fits to high temperature data yield θ of −13.1, −3.9, −8.2 and −5.0 K, respectively, in χ{sub M}=C/(T−θ). The net antiferromagnetic exchange yields susceptibility maxima at 6.34, 3.20, 2.10, and 3.40 K, with χ{sub max} of 0.197, 0.357, 0.465 and 0.348 emu/mol, respectively. Noteworthy is the contrast between dideuterate and dihydrate, the largest deuteration effect observed for hydrated transition metal halides. Antiferromagnetic ordering is estimated to occur at 5.91, 2.65, 2.00 and 2.50 K, respectively. The ratio T{sub c}/T{sub max} is 0.93, 0.83, 0.95 and 0.74 in the same order, implying low dimensional magnetism for monohydrate and monodeuterate. Heisenberg model fits to susceptibilities yield primary and secondary exchange interactions. Magnetization data at moderate fields and different temperatures are presented for each substance, and high field data to 70 kG at 2.00 K. Spin-flop transitions are estimated to occur at 45, 33 and 30 kG, respectively, for dihydrate, monohydrate and monodeuterate, but are not observable for MnBr{sub 2}·2D{sub 2}O. The results are analyzed from various perspectives. A different monoclinic unit cell is determined for MnBr{sub 2}·2D{sub 2}O than for MnBr{sub 2}·2H{sub 2}O, with 1.3% larger volume, providing some rationale for the difference in magnetic properties. - Highlights: • The magnetic properties of Mn(II) bromide dihydrate and monohydrate are studied. • The effects of replacing H{sub 2}O by D{sub 2}O are examined for both hydration states. • For monohydrate the change in magnetic behavior on deuteration is small. • For dihydrate the change in magnetic behavior on deuteration is large. • The unit cell of MnBr{sub 2}·2D{sub 2}O is different from and slightly larger than for MnBr{sub 2}·2H{sub 2}O.

  14. Bronchodilator efficacy of extrafine glycopyrronium bromide: the Glyco 2 study

    Directory of Open Access Journals (Sweden)

    Singh D

    2017-07-01

    Full Text Available Dave Singh,1 Mario Scuri,2 Sara Collarini,2 Stefano Vezzoli,2 Fabrizia Mariotti,2 Annamaria Muraro,2 Daniela Acerbi2 1Medicines Evaluation, University Of Manchester, University Hospital of South Manchester, Manchester, UK; 2Global Clinical Development, Chiesi Farmaceutici SpA, Parma, Italy Abstract: An extrafine formulation of the long-acting muscarinic antagonist glycopyrronium bromide (GB is in development for chronic obstructive pulmonary disease (COPD, in combination with beclometasone dipropionate and formoterol fumarate – a “fixed triple”. This two-part study was randomized, double blind, placebo controlled in patients with moderate-to-severe COPD: Part 1: single-dose escalation, GB 12.5, 25, 50, 100 or 200 µg versus placebo; Part 2: repeat-dose (7-day, four-period crossover, GB 12.5, 25 or 50 µg twice daily (BID versus placebo, with an open-label extension in which all patients received tiotropium 18 µg once daily. On the morning of Day 8 in all five periods, patients also received formoterol 12 µg. In study Part 1, 27 patients were recruited. All GB doses significantly increased from baseline forced expiratory volume in 1 second (FEV1 area under the curve (AUC0–12h and peak FEV1, with a trend toward greater efficacy with higher GB dose. All adverse events were mild–moderate in severity, with a lower incidence with GB than placebo and no evidence of a dose–response relationship. In study Part 2, of 38 patients recruited, 34 completed the study. Adjusted mean differences from placebo in 12 h trough FEV1 on Day 7 (primary were 115, 142 and 136 mL for GB 12.5, 25 and 50 µg BID, respectively (all P<0.001. GB 25 and 50 µg BID were superior (P<0.05 to GB 12.5 µg BID for pre-dose morning FEV1 on Day 8. For this endpoint, GB 25 and 50 µg BID were also superior to tiotropium. Compared with Day 7, addition of formoterol significantly increased Day 8 FEV1 peak and AUC0–12h with all GB doses and placebo (all P<0.001. All

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

    Science.gov (United States)

    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.

  16. Comparison of salbutamol and ipratropium bromide versus salbutamol alone in the treatment of acute severe asthma.

    Science.gov (United States)

    Hossain, A S; Barua, U K; Roy, G C; Sutradhar, S R; Rahman, I; Rahman, G

    2013-04-01

    The use of nebulized Ipratropium bromide, quaternary anticholinergic bronchodilators in combination with beta-agonist for the treatment of acute asthma in adults is controversial. In a view of different recommendation the present study is undertaken in Bangladeshi patients. Combination of inhaled Ipratropium bromide and Salbutamol provides greater bronchodilatation than mono therapy with Salbutamol alone in acute severe asthma. Patients of severe asthma (PEFR Salbutamol only) and case (Salbutamol + Ipratropium bromide) group. After measurement of peak expiratory flow, patient received 3 doses of 2.5 mg Salbutamol (n=40) only or 3 doses of both 2.5mg Salbutamol and 500mcg Ipratropium bromide at an interval of 20 minutes (n=40) through a jet nebulizer. Peak flow was reassessed 30 & 60 minutes after treatment. Peak flow at baseline was similar in two groups. Then at 30 minutes after nebulization, the mean±SD percentage increase in peak flow was greater in combination group (60.01±35.01%) than Salbutamol group (44.47±25.03%) with difference of 16% (p=0.025). At 60 minutes the percentage increase in peak flow was about 32% greater in combination group than Salbutamol group (94.44±33.70% vs. 62.57±29.26%, p=0.000) and combination group reached percentage predicted peak flow more than 60% while Sabutamol group did not. Ipratropium Bromide and Salbutamol nebulized combinedly have better bronchodilating effect than Salbultamol alone in acute severe asthma.

  17. The role of dysprosium on the structural and magnetic properties of (Nd1-xDyx)2Fe14B nanoparticles

    Science.gov (United States)

    Rahimi, Hamed; Ghasemi, Ali; Mozaffarinia, Reza; Tavoosi, Majid

    2017-02-01

    In current work, Nd2Fe14B nanoparticles was synthesized by sol-gel method. Dysprosium powders were added into Nd2Fe14B nanoparticles by mechanical alloying process in order to enhancement of coercivity. The phase analysis, structure, and magnetic properties of annealed (Nd1-xDyx)2Fe14B nanoparticles with different Dy-content (x=0.1, 0.2, 0.3, 0.4, 0.5, 0.6) were investigated by employing X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, field emission scanning electron microscope, transmission electron microscope and vibrating sample magnetometer techniques. The results showed that with an increase in Dy amounts, the coercivity of particles increased from 2.9 kOe to 13.4 kOe and then decreased to 5.6 kOe. By adding an optimum amount of Dy (x=0.4), the coercivity was significantly increased from 2.9 kOe to 13.4 kOe. The average particle size of annealed (Nd1-xDyx)2Fe14B nanoparticles was below 10 nm. Magnetization reversal studies indicate that the coercivity of milled and annealed (Nd1-xDyx)2Fe14B nanoparticles is controlled by the nucleation of reversed magnetic domains. The experimental results in the angular dependence of coercivity for (Nd1-xDyx)2Fe14B permanent magnets showed that the normalized coercivity of the permanent magnets Hc(θ)/Hc(0) increases from 1 to about 1.2-1.5 with increasing θ from 0 to about π/3, for x=0.4-0.6.

  18. Alternatives to methyl bromide treatments for stored-product and quarantine insects.

    Science.gov (United States)

    Fields, Paul G; White, Noel D G

    2002-01-01

    Methyl bromide is used to control insects as a space fumigant in flour and feed mills and ship holds, as a product fumigant for some fruit and cereals, and for general quarantine purposes. Methyl bromide acts rapidly, controlling insects in less than 48 h in space fumigations, and it has a wide spectrum of activity, controlling not only insects but also nematodes and plant-pathogenic microbes. This chemical will be banned in 2005 in developed countries, except for exceptional quarantine purposes, because it depletes ozone in the atmosphere. Many alternatives have been tested as replacements for methyl bromide, from physical control methods such as heat, cold, and sanitation to fumigant replacements such as phosphine, sulfuryl fluoride, and carbonyl sulfide, among others. Individual situations will require their own type of pest control techniques, but the most promising include integrated pest management tactics and combinations of treatments such as phosphine, carbon dioxide, and heat.

  19. Salty glycerol versus salty water surface organization: bromide and iodide surface propensities.

    Science.gov (United States)

    Huang, Zishuai; Hua, Wei; Verreault, Dominique; Allen, Heather C

    2013-07-25

    Salty NaBr and NaI glycerol solution interfaces are examined in the OH stretching region using broadband vibrational sum frequency generation (VSFG) spectroscopy. Raman and infrared (IR) spectroscopy are used to further understand the VSFG spectroscopic signature. The VSFG spectra of salty glycerol solutions reveal that bromide and iodide anions perturb the interfacial glycerol organization in a manner similar as that found in aqueous halide salt solutions, thus confirming the presence of bromide and iodide anions at the glycerol surface. Surface tension measurements are consistent with the surface propensity suggested by the VSFG data and also show that the surface excess increases with increasing salt concentration, similar to that of water. In addition, iodide is shown to have more surface prevalence than bromide, as has also been determined from aqueous solutions. These results suggest that glycerol behaves similarly to water with respect to surface activity and solvation of halide anions at its air/liquid interface.

  20. [Use of spasmolytic agent otilonium bromide (spasmomen) in digestive endoscopy: a prospective study in 63 patients].

    Science.gov (United States)

    Gómez, N A; León, C J; Gutiérrez, J

    1997-01-01

    Otilonium bromide is a calcium antagonist with a direct myolytic effect, that is indicated in spastic conditions and functional dyskinesias of the gastroenteric apparatus (irritable bowel syndrome) and as a premedication for gastrointestinal endoscopic procedures. The present study assessed otilonium bromide 40 mg PO the night before and 40 mg PO the morning in 49 upper and 14 lower flexible endoscopies in 63 patients, to determine the presence or absence of peristalsis and relaxation of the pylorus. No side effects were observed due to the medication. In 46 (93.8%) upper endoscopies marked relaxation of the gastrointestinal tract and also pylorus relaxation were observed. In 13 (92.8%) lower endoscopies, marked relaxation of the colonic tract was also seen. All patients tolerated well the endoscopies. Otilonium bromide was useful as premedication in order to enable upper and lower endoscopic explorations, because of its spasmolytic effect.

  1. Efficient Planar Heterojunction Perovskite Solar Cells Based on Formamidinium Lead Bromide.

    Science.gov (United States)

    Hanusch, Fabian C; Wiesenmayer, Erwin; Mankel, Eric; Binek, Andreas; Angloher, Philipp; Fraunhofer, Christina; Giesbrecht, Nadja; Feckl, Johann M; Jaegermann, Wolfram; Johrendt, Dirk; Bein, Thomas; Docampo, Pablo

    2014-08-21

    The development of medium-bandgap solar cell absorber materials is of interest for the design of devices such as tandem solar cells and building-integrated photovoltaics. The recently developed perovskite solar cells can be suitable candidates for these applications. At present, wide bandgap alkylammonium lead bromide perovskite absorbers require a high-temperature sintered mesoporous TiO2 photoanode in order to function efficiently, which makes them unsuitable for some of the above applications. Here, we present for the first time highly efficient wide bandgap planar heterojunction solar cells based on the structurally related formamidinium lead bromide. We show that this material exhibits much longer diffusion lengths of the photoexcited species than its methylammonium counterpart. This results in planar heterojunction solar cells exhibiting power conversion efficiencies approaching 7%. Hence, formamidinium lead bromide is a strong candidate as a wide bandgap absorber in perovskite solar cells.

  2. A study of the interaction between ethidium bromide and rye chromatin: comparison with calf thymus chromatin.

    Science.gov (United States)

    LaRue, H; Pallotta, D

    1976-09-01

    We studied the interaction of ethidium bromide with rye and calf thymus chromatin. Both types of chromatin have the same dye accessibility, which is about 50% of that of DNA. From this result we conclude that the molecular structure of these two chromatins is similar. For rye, the extraction of H1 produces no change in the binding of ethidium bromide. The subsequent extraction of H2A and H2B produces a 14% increase in the binding, and the removal of H3 and H4, another 54% increase. At this stage, the number of binding sites is still less than that of DNA. This is presumably due to the presence of some tightly bound non-histones. Thus, the arginine-rich histones and the tightly bound non-histones are most responsible for limiting the binding of ethidium bromide to rye chromatin.

  3. Valence photoelectron spectra of alkali bromides calculated within the propagator theory

    DEFF Research Database (Denmark)

    Karpenko, Alexander; Iablonskyi, Denys; Aksela, Helena

    2013-01-01

    The valence ionization spectra covering the binding energy range 0-45 eV of alkali bromide XBr (X = Li, Na, K, Rb) vapors are studied within the framework of the propagator theory. Relativistic Algebraic Diagrammatic Construction calculations have been carried out in order to investigate photoion......The valence ionization spectra covering the binding energy range 0-45 eV of alkali bromide XBr (X = Li, Na, K, Rb) vapors are studied within the framework of the propagator theory. Relativistic Algebraic Diagrammatic Construction calculations have been carried out in order to investigate...

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

    Science.gov (United States)

    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

  5. Halide-mediated regioselective 6-O-glycosylation of unprotected hexopyranosides with perbenzylated glycosyl bromide donors

    DEFF Research Database (Denmark)

    Niedbal, Dominika Alina; Madsen, Robert

    2016-01-01

    The regio- and stereoselective glycosylation at the 6-position in 2,3,4,6-unprotected hexopyranosides has been investigated with dibutyltin oxide as the directing agent. Perbenzylated hexopyranosyl bromides were employed as the donors and the glycosylations were promoted by tetrabutylammonium...... bromide. The couplings were completely selective for both glucose and galactose donors and acceptors as long as the stannylene acetal of the acceptor was soluble in dichloromethane. This gave rise to a number of 1,2-cis-linked disaccharides in reasonable yields. Mannose donors and acceptors, on the other...

  6. Well-Defined Copper(I) Fluoroalkoxide Complexes for Trifluoroethoxylation of Aryl and Heteroaryl Bromides

    KAUST Repository

    Huang, Ronglu

    2015-03-17

    © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Copper(I) fluoroalkoxide complexes bearing dinitrogen ligands were synthesized and the structure and reactivity of the complexes toward trifluoroethoxylation, pentafluoropropoxylation, and tetrafluoropropoxylation of aryl and heteroaryl bromides were investigated. Efficiency drive: A series of copper(I) fluoroalkoxide complexes bearing N,N ligands have been prepared and structurally characterized. These well-defined complexes serve as efficient reagents for the fluoroalkoxylation of aryl and heteroaryl bromides to produce a wide range of trifluoroethyl, pentafluoropropyl, and tetrafluoropropyl (hetero)aryl ethers in good to excellent yields.

  7. Thermodynamic evaluation of new absorbent mixtures of lithium bromide and organic salts for absorption refrigeration machines

    Energy Technology Data Exchange (ETDEWEB)

    Donate, Marina; Rodriguez, Luis; Lucas, Antonio De; Rodriguez, Juan F. [Department of Chemical Engineering, University of Castilla-La Mancha, Avda. de Camilo Jose Cela s/n, 13004 Ciudad Real (Spain)

    2006-01-01

    Mixtures of lithium bromide and organic salts of sodium and potassium (formate, acetate and lactate) have been evaluated as alternative absorbents for absorption refrigeration machines. The main objective is to overpass the limitations of lithium bromide and improve the characteristics and the efficiency of the refrigeration cycle. In order to select the mixture that presents better properties for its employment in absorption refrigeration cycles, a thermodynamic analysis have been done. Density, viscosity, enthalpies of dilution, solubility and vapour pressure data of the proposed mixtures have been measured. A simulation program has been developed to evaluate temperatures, heats exchanged in the different sections and the efficiency of the cycle. (author)

  8. Bromidotetrakis(2-ethyl-1H-imidazole-κN3copper(II bromide

    Directory of Open Access Journals (Sweden)

    Sylwia Godlewska

    2012-12-01

    Full Text Available The CuII ion in the title molecular salt, [CuBr(C5H8N24]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.

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

    Science.gov (United States)

    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.

  10. Comparison of injection drotaverine and injection valethamate bromide on duration and course of labor

    Directory of Open Access Journals (Sweden)

    Pradnya Rajendra Changede

    2016-06-01

    Results: The mean duration of active phase of first stage of labor was significantly shorter in the drotaverine and valethamate bromide groups as compared to control group in both primigravida and multigravida patients. Conclusions: The rate of cervical dilatation under the influence of valethamate bromide and drotaverine is significantly higher as compared to control group. In each group dilatation was faster in multigravida patients as compared to primigravida and it was fastest in the drotaverine group. [Int J Reprod Contracept Obstet Gynecol 2016; 5(6.000: 1836-1842

  11. Density functional study on ionic liquid of 1-propyl-4,5-dibromo-3-methylimidazolium bromide

    Science.gov (United States)

    Lü, Renqing; Wang, Shutao; Lu, Yukun

    2011-03-01

    The density functional method and DNP basis set were employed to study 1-pair, 2-pair, and 3-pair of cation-anion interactions of 1-propyl-4,5-dibromo-3-methylimidazolium bromides. The calculated results reveal that H 2 atoms of 1-propyl-4,5-dibromo-3-methylimidazolium form hydrogen bondings with Br -. The natural bond orbital (NBO) and atoms in molecules (AIM) analyzes show that halogen bondings between Br - anion and imidazolium ring substituted bromine atoms were formed in the gas phase, in agreement with the crystal phase of 1-propyl-4,5-dibromo-3-methylimidazolium bromide which is governed by both hydrogen bondings and halogen bondings.

  12. Uroporphyria development in cultured chick embryo fibroblasts long-term treated with chloramphenicol and ethidium bromide.

    Science.gov (United States)

    de Muys, J M; Morais, R

    1984-07-23

    Long-term chloramphenicol- and ethidium bromide-treated chick embryo fibroblasts synthesize large amounts of porphyrins from exogenously added delta-aminolevulinic acid. The porphyrins consist mainly of uro- and heptacarboxyporphyrins and are retained within cells. Uroporphyria development is a time-dependent process which accompanies a step-wise decrease in the capacity of the mitochondrial respiratory chain. Upon removal of chloramphenicol from the medium, the pattern of porphyrin production readily returns to normal (mainly proto- and coproporphyrins found in the medium) while ethidium bromide-treated cells remain uroporphyric. The results suggest that impairment of mitochondrial functions in chicken by xenobiotics leads to uroporphyria development.

  13. An efficient method for the preparation of tertiary esters by palladium-catalyzed alkoxycarbonylation of aryl bromides.

    Science.gov (United States)

    Xin, Zhuo; Gøgsig, Thomas M; Lindhardt, Anders T; Skrydstrup, Troels

    2012-01-06

    The palladium-catalyzed alkoxycarbonylation of aryl bromides is described for the efficient preparation of tertiary esters. The protocol proved compatible with a wide variety of functionalized (hetero)aromatic bromides, as well as several different sterically hindered tertiary alcohols, affording the alkoxycarbonylated products in high yields. Finally, the formation of aromatic trityl esters is discussed. © 2011 American Chemical Society

  14. The copper catalysed reaction of sodium methoxide with aryl bromides. A mechanistic study leading to a facile synthesis of anisole derivatives

    NARCIS (Netherlands)

    Koten, G. van; Aalten, H.L.; Grove, D.M.; Kuilman, T.; Piekstra, O.G.; Hulshof, L.A.; Sheldon, R.A.

    1989-01-01

    The copper catalysed reaction of unactivated aryl bromides with sodium methoxide has been investigated by studying a number of parameters (copper catalyst, cosolvent, concentration and relative ratio of the reactants, additives and aryl bromide substituents) which influence this reaction. The

  15. Mild Pd-catalyzed aminocarbonylation of (hetero)aryl bromides with a palladacycle precatalyst.

    Science.gov (United States)

    Friis, Stig D; Skrydstrup, Troels; Buchwald, Stephen L

    2014-08-15

    A palladacyclic precatalyst is employed to cleanly generate a highly active XantPhos-ligated Pd-catalyst. Its use in low temperature aminocarbonylations of (hetero)aryl bromides provides access to a range of challenging products in good to excellent yields with low catalyst loading and only a slight excess of CO. Some products are unattainable by traditional carbonylative coupling.

  16. Methyl Bromide Alternatives Area-Wide Pest Management Project - South Atlantic Progress Report

    Science.gov (United States)

    Protocols and Standard Operational Procedures (SOPs) were developed for collecting environmental and soil edaphic information during and after application of methyl bromide alternatives. Parameters measured included soil moisture, soil bulk density, percent moisture at field capacity (-0.3 bars wat...

  17. SYNTHESIS AND CATALYTIC PROPERTIES OF CROSS-LINKED HYDROPHOBICALLY ASSOCIATING POLY(ALKYLMETHYLDIALLYLAMMONIUM BROMIDES)

    NARCIS (Netherlands)

    WANG, GJ; ENGBERTS, JBFN

    1994-01-01

    Cross-linked, hydrophobically associating homo- and copolymers were synthesized by free-radical cyclo(co)polymerization of alkylmethyldiallylammonium bromide monomers with a small amount of N,N'-methylenebisacrylamide in aqueous solution using ammonium persulfate as the initiator. The cross-linked h

  18. Microwave-Enhanced Cross-Coupling Reactions Involving Alkynyltrifluoroborates with Aryl Bromides

    Directory of Open Access Journals (Sweden)

    George W. Kabalka

    2013-01-01

    Full Text Available Palladium-catalyzed alkynylation has emerged as one of the most reliable methods for the synthesis of alkynes which are often used in natural product syntheses and material science. An efficient method for coupling alkynyltrifluoroborates with various aryl bromides in the presence of a palladium catalyst has been developed using microwave irradiation. The microwave reactions are rapid and efficient.

  19. Palladium-catalyzed conversion of aryl and vinyl triflates to bromides and chlorides.

    Science.gov (United States)

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

    2010-10-13

    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.

  20. Aclidinium bromid forbedrer lungefunktionen og reducerer dyspnø hos patienter med KOL

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli

    2014-01-01

    Long-acting bronchodilators are central for treatment of COPD. This short review provides an overview of studies evaluating the efficacy of aclidinium bromide, a long-acting anticholinergic bronchodilator, for the treatment of COPD. Twice-daily dosing of aclidinium leads to clinically important...

  1. Palladium-catalyzed carbonylative synthesis of quinazolinones from 2-aminobenzamide and aryl bromides.

    Science.gov (United States)

    Wu, Xiao-Feng; He, Lin; Neumann, Helfried; Beller, Matthias

    2013-09-16

    C from CO! A straightforward procedure for the carbonylative synthesis of quinazolinones from readily available 2-aminobenzamide and aryl bromides has been developed. In the presence of a palladium catalyst, various quinazolinones were produced in moderate to excellent yields. Remarkably, no chromatography was needed for purification (see scheme).

  2. Palladium-catalyzed carbonylation reaction of aryl bromides with 2-hydroxyacetophenones to form flavones.

    Science.gov (United States)

    Wu, Xiao-Feng; Neumann, Helfried; Beller, Matthias

    2012-10-01

    Flavone of the month: a general and efficient method for the palladium-catalyzed carbonylative synthesis of flavones has been developed. Starting from aryl bromides and 2-hydroxyacetophenones, the corresponding flavones have been isolated in good yields. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Microwave-enhanced cross-coupling reactions involving alkynyltrifluoroborates with aryl bromides.

    Science.gov (United States)

    Coltuclu, Vitali; Dadush, Eric; Naravane, Abhijit; Kabalka, George W

    2013-01-29

    Palladium-catalyzed alkynylation has emerged as one of the most reliable methods for the synthesis of alkynes which are often used in natural product syntheses and material science. An efficient method for coupling alkynyltrifluoroborates with various aryl bromides in the presence of a palladium catalyst has been developed using microwave irradiation. The microwave reactions are rapid and efficient.

  4. Once-daily glycopyrronium bromide, a long-acting muscarinic antagonist, for chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli

    2012-01-01

    Long-acting bronchodilators are central in the pharmacological management of patients with chronic obstructive pulmonary disease (COPD). The aim of this systematic review is to provide an overview of the studies evaluating the safety and clinical efficacy of inhaled glycopyrronium bromide, a novel...

  5. An improved palladium-catalyzed conversion of aryl and vinyl triflates to bromides and chlorides.

    Science.gov (United States)

    Pan, Jun; Wang, Xinyan; Zhang, Yong; Buchwald, Stephen L

    2011-09-16

    A facile Pd-catalyzed conversion of aryl and vinyl triflates to aryl and vinyl halides (bromides and chlorides) is described. This method allows convenient access to a variety of aryl, heteroaryl, and vinyl halides in good to excellent yields and with greatly simplified conditions relative to our previous report. © 2011 American Chemical Society

  6. Valence photoelectron spectra of alkali bromides calculated within the propagator theory.

    Science.gov (United States)

    Karpenko, Alexander; Iablonskyi, Denys; Aksela, Helena

    2013-04-28

    The valence ionization spectra covering the binding energy range 0-45 eV of alkali bromide XBr (X = Li, Na, K, Rb) vapors are studied within the framework of the propagator theory. Relativistic Algebraic Diagrammatic Construction calculations have been carried out in order to investigate photoionization processes and to describe molecular electronic structure. Theoretical results are compared with available experimental data.

  7. Efficient palladium-catalyzed coupling reactions of aryl bromides and chlorides with phenols.

    Science.gov (United States)

    Hu, Tongjie; Schulz, Thomas; Torborg, Christian; Chen, Xiaorong; Wang, Jun; Beller, Matthias; Huang, Jun

    2009-12-21

    A convenient and general palladium-catalyzed coupling reaction of aryl bromides and chlorides with phenols was developed. Various functional groups such as nitriles, aldehydes, ketones and esters are well tolerated and the corresponding products are obtained in good to excellent yield.

  8. Highly efficient synthesis of phenols by copper-catalyzed hydroxylation of aryl iodides, bromides, and chlorides.

    Science.gov (United States)

    Yang, Kai; Li, Zheng; Wang, Zhaoyang; Yao, Zhiyi; Jiang, Sheng

    2011-08-19

    8-Hydroxyquinolin-N-oxide was found to be a very efficient ligand for the copper-catalyzed hydroxylation of aryl iodides, aryl bromides, or aryl chlorides under mild reaction conditions. This methodology provides a direct transformation of aryl halides to phenols and to alkyl aryl ethers. The inexpensive catalytic system showed great functional group tolerance and excellent selectivity. © 2011 American Chemical Society

  9. Nickel-catalyzed sonogashira reactions of non-activated secondary alkyl bromides and iodides.

    Science.gov (United States)

    Yi, Jun; Lu, Xi; Sun, Yan-Yan; Xiao, Bin; Liu, Lei

    2013-11-18

    A nicked reaction: The title reaction of terminal alkynes with non-activated secondary alkyl iodides and bromides was accomplished for the first time. This reaction provides a new and practical approach for the synthesis of substituted alkynes (see scheme; cod=cyclo-1,5-octadiene). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Palladium-catalyzed carbonylative sonogashira coupling of aryl bromides using near stoichiometric carbon monoxide

    DEFF Research Database (Denmark)

    Neumann, Karoline T.; Laursen, Simon R.; Lindhardt, Anders T.

    2014-01-01

    A general procedure for the palladium-catalyzed carbonylative Sonogashira coupling of aryl bromides is reported, using near stoichiometric amounts of carbon monoxide. The method allows a broad substrate scope in moderate to excellent yields. The formed alkynone motive serves as a platform...

  11. 76 FR 29238 - Methyl Bromide; Cancellation Order for Registration Amendments To Terminate Certain Soil Uses

    Science.gov (United States)

    2011-05-20

    ... AGENCY Methyl Bromide; Cancellation Order for Registration Amendments To Terminate Certain Soil Uses... for the amendments to terminate soil uses, voluntarily requested by the registrants and accepted by... Corporation. 5785-48 Terr-O-Gas 50 Great Lakes Chemical Corporation. 8536-05 Pic-Brom 33 Soil...

  12. 77 FR 29341 - Protection of Stratospheric Ozone: Request for Methyl Bromide Critical Use Exemption Applications...

    Science.gov (United States)

    2012-05-17

    .... Alternatives for which such information is needed include: Sulfuryl fluoride, propylene oxide (PPO), phosphine... costs to retrofit equipment or design and construct new fumigation chambers for these alternatives. For...) that are not needed when methyl bromide is used for fumigation. Include information on the size...

  13. Distribution of bromine in mixed iodide-bromide organolead perovskites and its impact on photovoltaic performance

    NARCIS (Netherlands)

    Zhou, Yang; Wang, Feng; Fang, Hong-Hua; Loi, Maria Antonietta; Xie, Fang-Yan; Zhao, Ni; Wong, Ching-Ping

    2016-01-01

    Mixed iodide-bromide (I-Br) organolead perovskites are of great interest for both single junction and tandem solar cells since the optical bandgap of the materials can be tuned by varying the bromine to iodine ratio. Yet, it remains unclear how bromine incorporation modifies the properties of the pe

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

    Science.gov (United States)

    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.

  15. Measurement and Computation of Movement of Bromide Ions and Carbofuran in Ridged HUmic-Sandy Soil

    NARCIS (Netherlands)

    Leistra, M.; Boesten, J.J.T.I.

    2010-01-01

    Water flow and pesticide transport in the soil of fields with ridges and furrows may be more complex than in the soil of more level fields. Prior to crop emergence, the tracer bromide ion and the insecticide carbofuran were sprayed on the humic-sandy soil of a potato field with ridges and furrows. R

  16. Ozone decomposition under the irradiation of 253.7 nm in the presence of methyl bromide

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper the mechanism and kinetic of ozone decomposition under the irradiation of 253.7 nm UV-light were studied.The quantum yield of the ozone depletion in the presence of methyl bromide is further determined and a reaction model is provided to explain the experimental fact.

  17. Simultaneous determination of otilonium bromide and diazepam by first-derivative spectroscopy.

    Science.gov (United States)

    Mannucci, C; Bertini, J; Cocchini, A; Perico, A; Salvagnini, F; Triolo, A

    1992-12-01

    A rapid, simple assay procedure was developed for simultaneous analysis of otilonium bromide, a smooth-muscle relaxant, and diazepam in tablets containing 20 mg of otilonium bromide and 2 mg of diazepam (20:2 tablets) or 40 mg of otilonium bromide and 2 mg of diazepam (40:2 tablets) by "zero-crossing" first-derivative spectroscopy. The tablets were dissolved in 0.01 N HCl, mixtures were centrifuged at 3500 rpm (2472 x g) for 5 min, and first-derivative spectra were recorded. The absolute values of the derivative were measured at 264 nm for determination of otilonium bromide and between 406 and 408 nm (380 nm for analysis of 40:2 tablets) for determination of diazepam. The method is linear, quantitative, and reproducible and can also be used for the tablet dissolution test. Ten tablets of the same batch were analyzed by the described method and by a high-performance liquid chromatographic method, and the results were in good agreement.

  18. Effects exerted by otilonium bromide administration on precipitated opioid withdrawal syndrome in rats.

    Science.gov (United States)

    Pinelli, A; Trivulzio, S; Vignati, S

    1997-09-26

    An opioid withdrawal syndrome was induced in rats by repeated morphine administration and final naloxone injection. The withdrawal causes alteration of several physiological signs. The aim of the study was to prevent the altered physiological profiles by utilising otilonium bromide. Morphine was administered in three daily i.p. injections for 4 days at doses of 9, 16 and 25 mg/kg (1st day), 25, 25 and 50 mg/kg (2nd day), 50, 50 and 50 mg/kg (3rd day) and 50, 50 and 100 mg/kg (4th day). Naloxone was injected (30 mg/kg) i.p. 180 min after the last morphine injection. Otilonium bromide was administered orally at 0, 2, 4 and 8 mg/kg, 120 min before the naloxone administration. Signs like faecal and urine excretion, rectal temperature and pain threshold levels, salivation, jumping and wet dog shakes were affected in different ways. Notably the administration of otilonium bromide in rats receiving morphine together with naloxone decreased the intensity of certain withdrawal symptoms, such as excretion of faeces, wet dog shake behaviour, and elevated the nociceptive threshold values. The effects exhibited by otilonium bromide administration may be explained through its calcium antagonist activity interfering with a mechanism involved in the regulation of these previously mentioned withdrawal symptoms. The use of this drug is thus suggested as a possible control of some acute opioid withdrawal signs in heroin addicts.

  19. Otilonium bromide inhibits calcium entry through L-type calcium channels in human intestinal smooth muscle.

    Science.gov (United States)

    Strege, P R; Evangelista, S; Lyford, G L; Sarr, M G; Farrugia, G

    2004-04-01

    Otilonium bromide (OB) is used as an intestinal antispasmodic. The mechanism of action of OB is not completely understood. As Ca(2+) entry into intestinal smooth muscle is required to trigger contractile activity, our hypothesis was that OB blocked Ca(2+) entry through L-type Ca(2+) channels. Our aim was to determine the effects of OB on Ca(2+), Na(+) and K(+) ion channels in human jejunal circular smooth muscle cells and on L-type Ca(2+) channels expressed heterologously in HEK293 cells. Whole cell currents were recorded using standard patch clamp techniques. Otilonium bromide (0.09-9 micromol L(-1)) was used as this reproduced clinical intracellular concentrations. In human circular smooth muscle cells, OB inhibited L-type Ca(2+) current by 25% at 0.9 micromol L(-1) and 90% at 9 micromol L(-1). Otilonium bromide had no effect on Na(+) or K(+) currents. In HEK293 cells, 1 micromol L(-1) OB significantly inhibited the expressed L-type Ca(2+) channels. Truncation of the alpha(1C) subunit C and N termini did not block the inhibitory effects of OB. Otilonium bromide inhibited Ca(2+) entry through L-type Ca(2+) at concentrations similar to intestinal tissue levels. This effect may underlie the observed muscle relaxant effects of the drug.

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

    Science.gov (United States)

    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 ...

  1. SYBR safe(TM) efficiently replaces ethidium bromide in Aspergillus fumigatus gene disruption.

    Science.gov (United States)

    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.

  2. Strontium and bromide as tracers in X-ray microanalysis of biological tissue

    Energy Technology Data Exchange (ETDEWEB)

    Wroblewski, J.; Sagstroem, S.M.; Mulders, H.; Roomans, G.M. (Karolinska Institutet, Stockholm (Sweden))

    1989-09-01

    Since energy dispersive X-ray microanalysis cannot distinguish between isotopes of the same element, alternative methods have to be used to get information similar to that obtained in experiments with radioactive tracers. In the present study, strontium was used as a tracer for calcium, and bromide as a tracer for chloride. Rats were injected with strontium chloride in vivo, and the uptake of strontium in the acinar cells of the submandibular gland was studied. Eventually a Sr/Ca ratio of 0.3 was reached. In some animals, secretion of mucus had been elicited by stimulation with isoproterenol 4 h prior to injection of strontium chloride. Exchange of calcium for strontium was enhanced by prior injection with isoproterenol. In a second experiment, rats were injected with sodium bromide, and the uptake of bromide by the submandibular acinar cells was followed in time, both in pilocarpine-stimulated and unstimulated glands. Under the experimental conditions, bromide was rapidly taken up by the cells, and the cellular Br/Cl ratio was close to that found in serum. Submandibular glands take up Br somewhat faster than other tissues (liver, heart muscle, skeletal muscle). The uptake of Br in pancreatic acinar cells was studied in vitro. These experiments showed a 1:1 ratio (molar) exchange of Cl for Br.

  3. Experimental study of negative temperatures in lithium-bromide absorption refrigerating machines

    Science.gov (United States)

    Stepanov, K. I.; Mukhin, D. G.; Alekseenko, S. V.; Volkova, O. V.

    2015-07-01

    The authors have developed a method and presented experimental data for obtaining negative temperatures of evaporation in lithium-bromide absorption chillers driven by heat recovery. It has been found that the attainable temperature of the refrigerated medium is the value of -5 °C.

  4. Kinetics and mechanism of the oxidation of bromide by periodate in aqueous acidic solution.

    Science.gov (United States)

    Szél, Viktor; Csekő, György; Horváth, Attila K

    2014-11-13

    The periodate–bromide reaction has been studied spectrophotometrically mainly in excess of bromide ion, monitoring the formation of the total amount of bromine at 450 nm at acidic buffered conditions and at a constant ionic strength in the presence of a phosphoric acid/dihydrogen phosphate buffer. The stoichiometry of the reaction was established to be strictly IO4(–) + 2Br(–) + 2H(+) → Br2 + IO3(–) + H2O. The formal kinetic order of the reactants was found to be perfectly one and two in the cases of periodate and bromide, respectively, but that of the hydrogen ion lies between one and two. We have also provided experimental evidence that dihydrogen phosphate accelerates the formation of bromine, suggesting the appearance of strong buffer assistance. On the basis of the experiments, a simple two-step kinetic model is proposed involving BrIO3 as a key intermediate that perfectly explains all of the experimental findings. Furthermore, we have also shown that in huge excess of bromide, the apparent rate coefficient obtained from the individual curve fitting method of the absorbance–time series is necessarily independent of the initial periodate concentration that may falsely be interpreted as the rate of bromine formation is also independent of the concentration of periodate.

  5. The carbonylation of phenyl bromide and its derivatives under visible light irradiation

    Institute of Scientific and Technical Information of China (English)

    Wen Hui Zhong; Ying Na Cui; Shen Min Li; Ying Ping Jia; Jing Mei Yin

    2012-01-01

    The carbonylation of phenyl bromide catalyzed by Co(OAc)2 has been investigated with PhCOPh as a sensitizer under visible light in the presence of basic additive.With strong base CH3ONa,PhCOOCH3 is produced in 70% yield with 100% selectivity,the similar results are also obtained with a stronger base (CH3)3CONa.However,with another strong base NaOH,the yield of the ester is only 40%.On the other hand,with weak base NaOAc or (n-C4Hg)3N,phenyl bromide cannot be carbonylated.The results of carbonylation of the six substituted phenyl bromides suggest that the activities of o,m,p-BrC6H4CH3 are similar to phenyl bromide,while the activities of o,m,p-BrC6H4Cl are higher with the high yields (≥93%) of the corresponding chloro-esters.In addition,the relative position of bromine and chlorine or methyl on phenyl ring has little effect on the activity of the carbonylation.

  6. Palladium Catalyzed Suzuki Cross-coupling Reaction in Molten Tetra-n-butylammonium Bromide

    Institute of Scientific and Technical Information of China (English)

    ZOU, Yue(邹岳); WANG, Quan-Rui(王全瑞); TAO, Feng-Gang(陶凤岗); DING, Zong-Biao(丁宗彪)

    2004-01-01

    A practical procedure for palladium catalyzed Suzuki cross-coupling reaction of arylboronic acids with aryl halides, including aryl chlorides in molten tetra-n-butylammonium bromide (TBAB) was developed. The reaction exhibits high efficiency and functional group tolerance. The recovery of the catalyst and molten n-Bu4NBr was also investigated.

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

    Science.gov (United States)

    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...

  8. METHOD OF INFRARED SPECTRA REGISTRATION OF ACTIVATED CARBONS IN POTASSIUM BROMIDE PELLETS

    Directory of Open Access Journals (Sweden)

    Diana Shepel

    2015-06-01

    Full Text Available This communication is devoted to the elaboration of a new optimal technique of infrared spectra registration of activated carbons in potassium bromide pellets. Authors investigated the dependence of the intensity of the least overlapping infrared bands of activated carbons on the conditions of preparation, recording of the spectrum, and the degree of homogenization with KBr.

  9. Detection of DNA cross-links in tumor cells with the ethidium bromide fluorescence assay

    NARCIS (Netherlands)

    de Jong, Steven; Zijlstra, J G; Timmer-Bosscha, H; Mulder, N H; de Vries, Liesbeth

    1986-01-01

    Until now the fluorescence assay with ethidium bromide has only been used on pure DNA. This assay depends on the difference in fluorescence between single- and double-stranded DNA (dsDNA). Cross-links in DNA are measured by the return of fluorescence of dsDNA after heat denaturation at pH 12. Under

  10. Iodine catalyzed and tertiary butyl ammonium bromide promoted p reparation of b enzoxazaphosphininyl phenylboronates

    Directory of Open Access Journals (Sweden)

    K. R. Kishore K. Reddy,

    2009-05-01

    Full Text Available Benzoxazaphosphininyl Phenylboronates were prepared by O-Phosphorylation of potassium salt ofphenylboronic acid with cyclic phosphoromonochloridates in the presence of stoichiometric amount of Iodineand catalytic amount of tertiary butyl ammonium bromide at 50-60 °C in dry toluene.

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

    Science.gov (United States)

    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

  12. Dielectric relaxation losses in lead chloride and lead bromide: Localized dipoles

    NARCIS (Netherlands)

    Brom, W.E. van den; Volger, J.

    1974-01-01

    A further analysis of previous reported measurements of dielectric relaxation losses in lead chloride and lead bromide crystals shows that the dipoles may occupy several energetically different positions, giving rise to localization of the dipoles and anomalous behaviour of the susceptibility. This

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

    Science.gov (United States)

    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...

  14. Palladium-Catalyzed Carbonylation of Aryl Bromides with N-Substituted Cyanamides

    DEFF Research Database (Denmark)

    Lian, Zhong; Friis, Stig D.; Lindhardt, Anders T.;

    2014-01-01

    The palladium(0)-catalyzed three-component coupling reaction of aryl bromides, carbon monoxide, and N-alkyl cyan­amides has been developed employing a two-chamber system with ex situ generation of carbon monoxide from a silacarboxylic acid. The reactions proceeded well and were complete with a re...

  15. Sn-free Ni-catalyzed reductive coupling of glycosyl bromides with activated alkenes.

    Science.gov (United States)

    Gong, Hegui; Andrews, R Stephen; Zuccarello, Joseph L; Lee, Stephen J; Gagné, Michel R

    2009-02-19

    A mild, stereoselective method for the Ni-catalyzed synthesis of alpha-C-alkylglycosides is reported. This approach entails the reductive coupling of glycosyl bromides with activated alkenes at room temperature, with low alkene loading as an important feature. Diastereoselective coupling with 2-substituted acrylate derivatives was made possible through the use of 2,4-dimethyl-3-pentanol as a proton source.

  16. Distribution of bromine in mixed iodide-bromide organolead perovskites and its impact on photovoltaic performance

    NARCIS (Netherlands)

    Zhou, Yang; Wang, Feng; Fang, Hong-Hua; Loi, Maria Antonietta; Xie, Fang-Yan; Zhao, Ni; Wong, Ching-Ping

    2016-01-01

    Mixed iodide-bromide (I-Br) organolead perovskites are of great interest for both single junction and tandem solar cells since the optical bandgap of the materials can be tuned by varying the bromine to iodine ratio. Yet, it remains unclear how bromine incorporation modifies the properties of the pe

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

    Directory of Open Access Journals (Sweden)

    J. Liao

    2012-02-01

    Full Text Available A focus of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS mission was examination of bromine photochemistry in the spring time high latitude troposphere based on aircraft and satellite measurements of bromine oxide (BrO and related species. The NASA DC-8 aircraft utilized a chemical ionization mass spectrometer (CIMS to measure BrO and a mist chamber (MC to measure soluble bromide. We have determined that the MC detection efficiency to molecular bromine (Br2, hypobromous acid (HOBr, bromine oxide (BrO, and hydrogen bromide (HBr as soluble bromide (Br was 0.9±0.1, 1.06+0.30/−0.35, 0.4±0.1, and 0.95±0.1, respectively. These efficiency factors were used to estimate soluble bromide levels along the DC-8 flight track of 17 April 2008 from photochemical calculations constrained to in situ BrO measured by CIMS. During this flight, the highest levels of soluble bromide and BrO were observed and atmospheric conditions were ideal for the space-borne observation of BrO. The good agreement (R2 = 0.76; slope = 0.95; intercept = −3.4 pmol mol−1 between modeled and observed soluble bromide, when BrO was above detection limit (>2 pmol mol−1 under unpolluted conditions (NO<10 pmol mol−1, indicates that the CIMS BrO measurements were consistent with the MC soluble bromide and that a well characterized MC can be used to derive mixing ratios of some reactive bromine compounds. Tropospheric BrO vertical column densities (BrOVCD derived from CIMS BrO observations compare well with BrOTROPVCD from OMI on 17 April 2008.

  18. Dysprosium(III) complexes with a square-antiprism configuration featuring mononuclear single-molecule magnetic behaviours based on different β-diketonate ligands and auxiliary ligands.

    Science.gov (United States)

    Zhang, Sheng; Ke, Hongshan; Shi, Quan; Zhang, Jangwei; Yang, Qi; Wei, Qing; Xie, Gang; Wang, Wenyuan; Yang, Desuo; Chen, Sanping

    2016-03-28

    Three mononuclear dysprosium(III) complexes derived from three β-diketonate ligands, 4,4,4-trifluoro-1-(4-methylphenyl)-1,3-butanedione (tfmb), 4,4,4-trifluoro-1-(4-fluorophenyl)-1,3-butanedione (tffb) and 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione (tfnb) as well as auxiliary ligands, 5-nitro-1,10-phenanthroline (5-NO2-Phen), DMF and 2,2'-bipyridine (bpy) have been synthesized and structurally characterized, namely [Dy(5-NO2-Phen)(tfmb)3] (1), [Dy(DMF)2(tffb)3] (2) and [Dy(bpy)2(tfnb)3]·0.5(1,4-dioxane) (3). The metal ions in 1-3 adopt an approximately square-antiprismatic (SAP) coordination environment with D4d axial symmetry. The magnetic properties of 1-3 have been investigated, displaying weak out-of-phase AC signals under a zero-DC field. With an applied DC field of 1200 Oe, the quantum tunnelling of the magnetization was suppressed in 1-3 with the pre-exponential factor τ0 = 5.3 × 10(-7) s and the effective barrier ΔE/kB = 83 K for 1 as well as the pre-exponential factor τ0 = 3.09 × 10(-7) s and the effective barrier ΔE/kB = 39 K for 3. Interestingly, for the frequency dependence of the out-of-phase (χ'') of the AC susceptibility of 2, two slow relaxation of the magnetization processes occurred under the applied magnetic field of 1200 Oe, corresponding to the fast relaxation (FR) phase and slow relaxation (SR) phase, respectively. Arrhenius analysis gave the effective energy barrier (ΔE/kB) of 55 K and the pre-exponential factor (τ0) of 8.23 × 10(-12) for the SR. It is thus very likely that the FR process in complex 2 results from QTM enhanced by dipolar interactions between the Dy ions or the presence of the applied field. The structure-property relationship of some Dy(III) based mononuclear SMMs with the SAP configuration was further discussed.

  19. Magnetic Phase Transition of Nanocrystalline Bulk Metal Gadolinium and Dysprosium%纳米块体金属钆和镝的磁性相变分析

    Institute of Scientific and Technical Information of China (English)

    刘凤艳; 侯碧辉; 岳明; 王克军

    2011-01-01

    The magnetic properties of bulk nanocrystalline metal gadolinium (Gd) and dysprosium (Dy)samples were studied.The magnetization and Curie temperature TC of nanocrystalline Gd and Dy decreased usually as compared with the polycrystal.However,when the mean grain size was 10 nm, the Curie temperature Tc of nanocrystalline Dy increased to 100 K instead and there was an antiferromagnetic phase in nanocrystalline Gd.According to the calculation based on Ruderman-Kittel-Kasuya-Yosida exchange interaction, the exchange integral of the grain boundary atoms and crystalline surface atoms had its sign changed from plus to minus or vice versa, and there were three orderly phases in the steady state with the lowest energy, ferromagnetic phase, antiferromagnetic phase and fan phase.For the nanocrystals with mean grain size of 10 nm, the proportion of grain boundary to crystalline surface atoms was high, and as the result of superposition of the three phases, and there appeared a peak near the phase transition temperature for the nanocrystalline Gd.While for the Dy, the magnetization decreased gently with temperature, and showing a higher Curie temperature than in the case of the polycrystal.%对纳米晶钆(Gd)和镝(Dy)块体材料的磁性进行了研究.与多晶比较,通常纳米晶的磁化强度减小,居里温度TC降低,但平均粒径为10 nm的纳米晶Dy的居里温度TC反而升高到100 K,平均粒径为10 nm的纳米晶Gd中还存在明显的反铁磁相.通过RKKY交换作用的计算知道,晶面晶界处原子的交换积分会发生正负号的变化,能量最低的稳定状态对应三种有序相:铁磁相、反铁磁相和扇相,晶粒中在一定条件下出现三相共存.对于平均粒径为10 nm的纳米晶,晶面晶界处原子所占比例很大,三相叠加的结果,对于Gd,即是在相变点附近出现磁化强度尖峰;对于Dy,则是磁化强度随温度升高下降缓慢,表现为居里温度TC比多晶升高.

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

    Directory of Open Access Journals (Sweden)

    Shakhatreh MA

    2016-11-01

    Full Text Available Muhamad Ali K Shakhatreh,1 Mousa L Al-Smadi,2 Omar F Khabour,1,3 Fatima A Shuaibu,1 Emad I Hussein,4 Karem H Alzoubi51Department of Medical Laboratory Sciences, 2Department of Applied Chemical Sciences, Jordan University of Science and Technology, Irbid, Jordan; 3Faculty of Applied Medical Sciences, Taibah University, Madina, Saudi Arabia; 4Department of Biological Sciences, Yarmouk University, 5Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid, Jordan Abstract: 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-dimethylaminobenzaldehyde 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

  1. Effect of Ispaghula and Oxyphenonium Bromide on the Symptoms of Irritable Bowel Syndrome - A Comparative Study

    Directory of Open Access Journals (Sweden)

    B Paik

    2010-07-01

    Full Text Available Background: Irritable bowel syndrome is a chronic continuous or remittent gastrointestinal illness characterized byfrequent unexplained symptoms that include abdominal pain, bloating, and bowel disturbance, in our country, no studyhas been conducted using the Ispaghula husk and oxyphenonium bromide for the treatment of IBS patients. Objectives:To compare the efficacy of treatment with Ispaghula husk and Oxyphenonium bromide. Methods: Total sixty patientsdiagnosed clinically as irritable bowel syndrome irrespective of subtype who fulfilled the Rome II criteria were includedequally into two groups-Group-I (Ispaghula group & Group-II (Oxyphenonium group. In Group-I patients were given30gm of Ispaghula husk at night daily and in Group-II patients were given 5mg of oxyphenonium bromide. After sixweeks the clinical parameters of both the groups recorded in the case record forms were taken for analysis. Results: Themean age of the patients in the Group- I were 33.4±11.9 yrs and that of the patients in the Group-II were 31.0±17.5 yrs.Male and female ratio in group I was 14:1 and in group II was 23:7. Most of the patients were recorded in the age groupof 26-30 in both groups. Symptom free patients were graded in 16.7% patients in Group-I and in 20% patients in Group-II. No improvement was occurred in 16.7% patients in Group-I and in 10% patients in Group-II. Conclusions: Ispaghulahusk shows the better efficacy to improve the symptoms of IBS like abdominal pain or discomfort and sense of well beingthan Oxyphenonium bromide. Oxephenonium bromide shows the better efficacy to decrease the stool frequency frombase line than Ispaghula husk.DOI: 10.3329/bsmmuj.v3i1.5506BSMMU J 2010; 3(1: 3-8

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

    Science.gov (United States)

    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.

  3. Evaluation of the influence of base and alkyl bromide on synthesis of pyrazinoic acid esters through fatorial design

    Directory of Open Access Journals (Sweden)

    João Paulo dos Santos Fernandes

    2009-01-01

    Full Text Available Pyrazinoic acid esters have been synthesized as prodrugs of pyrazinoic acid. In the literature, its preparation is reported through the reaction of pyrazinoyl chloride with alcohols and the reaction with DCC/DMAP. In this work, it is reported a 2² factorial design to evaluate the preparation of these esters through the substitution of alkyl bromides with carboxylate anion. The controlled factors were alkyl chain length of bromides (ethyl and hexyl and the used base (triethylamine and DBU. Results revealed that the used base used has significant effect on yield, and alkyl bromide used has neither significant influence, nor its interaction effect with base.

  4. GREEN CHEMISTRY APPLICATION FOR THE SYNTHESIS OF (1)-N-4’-METHOXYBENZYL-1,10-PHENANTHROLINIUM BROMIDE

    OpenAIRE

    Firdaus, Maulidan; Jumina, Jumina; Anwar, Chairil

    2010-01-01

    A simple, energy-efficient, and relatively quick synthetic procedure for the synthesis of (1)-N-4'-methoxybenzyl-1,10-phenanthrolinium bromide, based on green chemistry principles has been carried out. The synthesis was started by solvent-free reduction of p-anisaldehyde with NaBH4 to give 4-methoxybenzyl alcohol in 98% yield to be followed by solvent-free treatment of the resulted alcohol with PBr3 to yield 4-methoxybenzyl bromide (86%). Furthermore, the obtained bromide was reacted with 1,1...

  5. Synthesis of polyhydroxylated pyrrolidines from sugar-derived bromonitriles through a cascade addition of allylmagnesium bromide/cyclization/reduction.

    Science.gov (United States)

    Malik, Michał; Jarosz, Sławomir

    2016-02-01

    The synthesis of polyhydroxylated 2-allylpyrrolidines from sugar-derived bromonitriles in a cascade addition of allylmagnesium bromide/SN2 cyclization/reduction with Zn(BH4)2 is described. The stereochemical course of the reduction step is rationalized. Two of the obtained compounds are transformed into stereoisomers of naturally-occurring iminosugar (+)-lentiginosine. In an alternative approach, 2,2-diallylpyrrolidines are obtained from bromonitriles in a cascade addition of allylmagnesium bromide/SN2 cyclization/addition of another equivalent of allylmagnesium bromide.

  6. Comparative microvascular exchange kinetics of [{sup 77}Br]bromide and {sup 99m}Tc-DTPA in humans

    Energy Technology Data Exchange (ETDEWEB)

    Cousins, Claire [Department of Clinical Radiology, Addenbrooke' s Hospital, Cambridge (United Kingdom); Skehan, Stephen J.; Rolph, Susan M.; Flaxman, Mary E.; Ballinger, James R.; Bird, Nicholas J.; Barber, Robert W.; Peters, Michael A. [Department of Nuclear Medicine, Addenbrooke' s Hospital, Cambridge (United Kingdom)

    2002-05-01

    The plasma clearance curves of small hydrophilic solutes comprise three exponentials, consistent with a three-compartmental distribution model. A previous comparison between inulin and diethylene triamine penta-acetic acid (DTPA) suggested that these three compartments are in series, the first being plasma and the second and third representing compartments within the extravascular space. Moreover, whilst the total distribution volumes of these two indicators were similar, the volume of the second compartment was higher for DTPA. The purpose of the current study was to investigate whether a solute smaller than DTPA, namely bromide, fits the hypothesis that the second space volume is an inverse function of the size of the solute. Two groups of subjects were studied: group A comprised eight patients undergoing routine diagnostic arteriography and group B, eight patients referred for routine measurement of glomerular filtration rate plus two normal volunteers. {sup 99m}Tc-DTPA and sodium [{sup 77}Br]bromide were intravenously administered simultaneously. In group A, frequent arterial samples were obtained up to 40 min after injection, and antecubital venous samples 30 s after each arterial sample. In group B, frequent venous samples were obtained up to 280 min after injection. Volume measurements based on bromide were corrected for erythrocyte bromide accumulation. In both subject groups, the normalised venous concentration ratio of bromide to DTPA, corrected for red cell bromide uptake, was significantly less than unity in the earliest blood samples, being 0.56 (SD 0.08) at 1 min, consistent with faster diffusion of bromide from plasma to interstitial fluid. Furthermore, the extraction fraction of bromide from plasma to interstitial fluid in the forearm was about 0.6, higher than that of DTPA (about 0.5) in spite of red cell bromide accumulation which equilibrated with plasma bromide within 20 s and resulted in a red cell to plasma concentration ratio of 0.51 (0

  7. Extension of the energy range of the experimental activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium up to 65 MeV

    CERN Document Server

    Tárkányi, F; Takács, S; Hermanne, A; Ignatyuk, A V

    2016-01-01

    Activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium were extended up to 65 MeV by using stacked foil irradiation and gamma spectrometry experimental methods. Experimental cross-sections data for the formation of the radionuclides $^{159}$Dy, $^{157}$Dy, $^{155}$Dy, $^{161}$Tb, $^{160}$Tb, $^{156}$Tb, $^{155}$Tb, $^{154m2}$Tb, $^{154m1}$Tb, $^{154g}$Tb, $^{153}$Tb, $^{152}$Tb and $^{151}$Tb are reported in the 36-65 MeV energy range, and compared with an old dataset from 1964. The experimental data were also compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction model code as listed in the latest on-line libraries TENDL 2013.

  8. Extension of the energy range of the experimental activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium up to 65MeV.

    Science.gov (United States)

    Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

    2015-04-01

    Activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium were extended up to 65MeV by using stacked foil irradiation and gamma spectrometry experimental methods. Experimental cross-sections data for the formation of the radionuclides (159)Dy, (157)Dy, (155)Dy, (161)Tb, (160)Tb, (156)Tb, (155)Tb, (154m2)Tb, (154m1)Tb, (154g)Tb, (153)Tb, (152)Tb and (151)Tb are reported in the 36-65MeV energy range, and compared with an old dataset from 1964. The experimental data were also compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction model code as listed in the latest on-line libraries TENDL 2013. Copyright © 2015. Published by Elsevier Ltd.

  9. Comparative study between 1-Propyl-3-methylimidazolium bromide and trimethylene bis-methylimidazolium bromide ionic liquids by FTIR/ATR and FT-RAMAN spectroscopies

    Science.gov (United States)

    Kadari, Mohamed; Belarbi, El Habib; Moumene, Taqiyeddine; Bresson, Serge; Haddad, Boumediene; Abbas, Ouissam; Khelifa, Brahim

    2017-09-01

    In this study, we synthesized two ionic liquids based on imidazolium: one is a monocationic and the other is a dicationic. They are respectively 1-Propyl-3-methylimidazolium bromide ([PrMIM+][Br-]) and trimethylene bis-methylimidazolium bromide ([M(CH2)3IM2+][2Br-]). The structures of these two ionic liquids which are composed of ions with atoms of the same nature were first identified by 1H,13C NMR, and then compared in a study by FT-RAMAN and FTIR/ATR spectroscopies. FT-RAMAN spectras of the dicationic ionic liquid are richer in modes in the different spectral regions. Hence this richness seems to be a consequence of the passage from one to two rings in the imidazolium cation. In particular, the vibrational modes in the spectral ranges 700-600 cm-1, 1700-1500 cm-1 and 3200-2700 cm-1 by FTIR/ATR seem to be sensitive to the change from mono to dicationic than in FT-RAMAN. The spectral range in which the intermolecular interactions are present (200-50 cm-1) is a marker of differentiation between the mono and the dicationic. The spectral ranges on 1700-1200 cm-1 and 3200-2700 cm-1 also show signs of upheaval between our two samples. We can also notice that there are much more active modes in FT-RAMAN spectroscopy than in FTIR/ATR spectroscopy.

  10. Thermodynamic Properties of Hydrogen + Tetra-n-Butyl Ammonium Bromide Semi-Clathrate Hydrate

    Directory of Open Access Journals (Sweden)

    Shunsuke Hashimoto

    2010-01-01

    Full Text Available Thermodynamic stability and hydrogen occupancy on the hydrogen + tetra-n-butyl ammonium bromide semi-clathrate hydrate were investigated by means of Raman spectroscopic and phase equilibrium measurements under the three-phase equilibrium condition. The structure of mixed gas hydrates changes from tetragonal to another structure around 95 MPa and 292 K depending on surrounding hydrogen fugacity. The occupied amount of hydrogen in the semi-clathrate hydrate increases significantly associated with the structural transition. Tetra-n-butyl ammonium bromide semi-clathrate hydrates can absorb hydrogen molecules by a pressure-swing without destroying the hydrogen bonds of hydrate cages at 15 MPa or over.

  11. Ni-catalyzed reductive homocoupling of unactivated alkyl bromides at room temperature and its synthetic application.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  13. Different Performance of Two Isomeric Phosphinobiphenyl Amidosulfonates in Pd-Catalyzed Cyanation of Aryl Bromides

    Directory of Open Access Journals (Sweden)

    Jiří Schulz

    2016-11-01

    Full Text Available A hydrophilic phosphinobiphenyl amidosulfonate, 2′-(dicyclohexylphosphino-2- {[(sulfonatomethylamino]carbonyl}[1,1′-biphenyl], triethylammonium salt (L2, was prepared and, together with its isomer bearing the polar amido-sulfonate tag in the position 4 of the biphenyl scaffold (compound L1, evaluated as a supporting ligand in Pd-catalyzed cyanation of aryl bromides using K4[Fe(CN6] as the non-toxic cyanide source. The less sterically demanding ligand L1 was found to form more active catalysts than the newly prepared compound L2. A catalyst formed in situ from palladium(II acetate and L1 efficiently mediated cyanation of aryl bromides bearing electron-donating substituents but failed in the analogous reactions with electron-poor substrates.

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

    Science.gov (United States)

    Ivey, Chris D; Ingersoll, Chris G

    2016-10-01

    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 of H. azteca in 42-d water-only exposures. Improved performance of H. azteca was observed in reconstituted waters with >0.02 mg Br/L. Environ Toxicol Chem 2016;35:2425-2429. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.

  15. Technical report. Video imaging of ethidium bromide-stained DNA gels with surface UV illumination.

    Science.gov (United States)

    Solioz, M

    1994-06-01

    We describe here the use of surface UV illumination to record ethidium bromide-stained DNA gels with a video camera. This mode of illumination allows the use of a standard video camera equipped with a red filter and results in a high signal strength. The assembly of a low-cost video system on this basis is described. It uses the public domain software called Image on a Macintosh computer and PostScript laser printer or a thermal printer to generate hard copies. The setup is sensitive enough to detect 500 pg of DNA on an ethidium bromide-stained DNA gel. The UV illumination method described here can also greatly improve the sensitivity of existing video recording equipment.

  16. Clinical and functional evaluation of the efficacy of otilonium bromide: a multicenter study in Italy.

    Science.gov (United States)

    Baldi, F; Longanesi, A; Blasi, A; Monello, S; Cestari, R; Missale, G; Corazziari, E; Badiali, G; Pescatori, M; Anastasio, G

    1991-11-01

    Seventy-two patients complaining of abdominal pain were studied in a double blind trial with otilonium bromide (OB) (40 mg tid or placebo). In our patients we performed, before and after the treatment, a clinical evaluation (symptom variations) and functional studies (sigmoid manometry during bowel distension). As regards clinical parameters, otilonium bromide significantly reduced abdominal pain and bloating and significantly increased (p less than 0.02) the pain threshold. However the comparison with the placebo group did not show any difference between the two groups. Sigmoid motility during distension was significantly reduced (p less than 0.05) in OB group, whereas it did not change in the placebo group. We can conclude that, in irritable bowel syndrome (IBS) patients, OB is able to improve symptoms and to reduce stimulated motor activity of the sigmoid.

  17. Underpotential deposition of Cu on Pt(001): Interface structure and the influence of adsorbed bromide

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, C.A. [Oliver Lodge Laboratory, Department of Physics, University of Liverpool, Liverpool, L697ZE (United Kingdom); Markovic, N.M.; Ross, P.N. [Materials Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States)

    1998-05-01

    Using {ital in situ} x-ray diffraction, we studied the underpotential deposition (UPD) of copper onto a Pt(001) electrode both in pure perchloric acid and in the presence of bromide anions. In pure perchloric acid, the Cu is deposited in pseudomorphic p(1{times}1) islands. In the presence of bromide anions, the strong Pt-Br interaction significantly broadens the potential range of Cu UPD. We propose that Br remains in the interface region throughout the UPD process, at first in a disordered Cu-Br phase and then, at more negative potential, forming a c(2{times}2) closed-packed monolayer on top of the completed p(1{times}1) Cu monolayer. The structures are compared to those found during Cu UPD onto Pt(111), and explained in terms of the metal-halide interactions and the Pt surface atomic geometry. {copyright} {ital 1998} {ital The American Physical Society}

  18. Facile Synthesis of Heterocycles via 2-Picolinium Bromide and Antimicrobial Activities of the Products

    Directory of Open Access Journals (Sweden)

    Elham S. Darwish

    2008-05-01

    Full Text Available The 2-picolinium N-ylide 4, generated in situ from the N-acylmethyl-2-picolinium bromide 3, underwent cycloaddition to N-phenylmaleimide or carbon disulfideto give the corresponding cycloadducts 6 and 8, respectively similar reactions ofcompound 3 with some electron-deficient alkenes in the presence of MnO2 yielded theproducts 11 and 12. In addition, reaction of 4 with arylidene cyanothioacetamide andmalononitrile derivatives afforded the thiophene and aniline derivatives 15 and 17,respectively. Heating of picolinium bromide 3 with triethylamine in benzene furnished 2-(2-thienylindolizine (18. The structures of the isolated products were confirmed byelemental analysis as well as by 1H- and 13C-NMR, IR, and MS data. Both thestereochemistry and the regioselectivity of the studied reactions are discussed. Thebiological activity of the newly synthesized compounds was examined and showedpromising results.

  19. A novel model-based approach for dose determination of glycopyrronium bromide in COPD

    Directory of Open Access Journals (Sweden)

    Arievich Helen

    2012-12-01

    Full Text Available Abstract Background Glycopyrronium bromide (NVA237 is an inhaled long-acting muscarinic antagonist in development for treatment of COPD. This study compared the efficacy and safety of once-daily (OD and twice-daily (BID glycopyrronium bromide regimens, using a novel model-based approach, in patients with moderate-to-severe COPD. Methods Double-blind, randomized, dose-finding trial with an eight-treatment, two-period, balanced incomplete block design. Patients (smoking history ≥10 pack-years, post-bronchodilator FEV1 ≥30% and 1/FVC 1 at Day 28. Results 385 patients (mean age 61.2 years; mean post-bronchodilator FEV1 53% predicted were randomized; 88.6% completed. All OD and BID dosing regimens produced dose-dependent bronchodilation; at Day 28, increases in mean trough FEV1 versus placebo were statistically significant for all regimens, ranging from 51 mL (glycopyrronium bromide 12.5 μg OD to 160 mL (glycopyrronium bromide 50 μg BID. Pharmacodynamic steady-state was reached by Day 7. There was a small separation (≤37 mL between BID and OD dose–response curves for mean trough FEV1 at steady-state in favour of BID dosing. Over 24 hours, separation between OD and BID regimens was even smaller (FEV1 AUC0-24h maximum difference for equivalent daily dose regimens: 8 mL. Dose–response results for FEV1 at 12 hours, FEV1 AUC0-12h and FEV1 AUC0-4h at steady-state showed OD regimens provided greater improvement over placebo than BID regimens for total daily doses of 25 μg, 50 μg and 100 μg, while the reverse was true for OD versus BID regimens from 12–24 hours. The 12.5 μg BID dose produced a marginally higher improvement in trough FEV1 versus placebo than 50 μg OD, however, the response at 12 hours over placebo was suboptimal (74 mL. Glycopyrronium bromide was safe and well tolerated at all doses. Conclusions Glycopyrronium bromide 50 μg OD provides significant bronchodilation over a 24 hour period

  20. Formation pathways of brominated products from benzophenone-4 chlorination in the presence of bromide ions

    Institute of Scientific and Technical Information of China (English)

    Ming Xiao; Dongbin Wei; Liping Li; Qi Liu; Huimin Zhao; Yuguo Du

    2014-01-01

    The brominated products,formed in chlorination treatment of benzophenone-4 in the presence of bromide ions,were identified,and the formation pathways were proposed.Under disinfection conditions,benzophenone-4 would undertake electrophilic substitution generating mono-or di-halogenated products,which would be oxidized to esters and further hydrolyzed to phenol derivatives.The generated catechol intermediate would be transformed into furan-like heterocyclic product.The product species were pH-dependent,while benzophenone-4 ehmination was chlorine dose-dependent.When the chlorination treatment was performed on ambient water spiked with benzophenone-4 and bromide ions,most of brominated byproducts could be detected,and the acute toxicity significantly increased as well.

  1. 3-Dodecyloxy-2-hydroxy-N,N,N-trimethylpropan-1-aminium bromide

    Directory of Open Access Journals (Sweden)

    Shizhou Fu

    2009-08-01

    Full Text Available In the title compound, C18H40NO2+·Br−, the ion pairs formed by the hydrogen-bonded bromide anions and organic cations are arranged into thick layers with the alkyl groups directed to the inside and the trimethylaminium groups and the bromide anions situated on the layer surface. The long alkyl chain in the cation adopts an all-trans conformation. In the crystal structure, molecules are connected by intermolecular O—H...Br hydrogen bonds, forming ionic pairs that are further connected into an extended chain structure via C—H...O hydrogen-bonding interactions. The crystal is chiral but nearly 90% of atoms in the unit cell are related by a pseudo-inversion center. The crystal shows racemic twinning with a 0.33:0.67 domain ratio.

  2. Synergistic Actions of Pyridostigmine Bromide and Insecticides on Muscle and Vascular Nociceptors

    Science.gov (United States)

    2014-01-01

    or increased the absorption of permethrin ( Baynes et al., 2002; Choi et al., 2004; Rose et al., 2005; see also Abu-Qare and Abou-Donia, 2008...widespread pain among veterans following the first Gulf War. Clin J Pain 22, 554-563. Baynes RE, Monteiro-Riviere NA, Riviere JE. Pyridostigmine bromide...Binns et al., 2008; Steele et al., 2011). Some of these agents increase absorption and/or retard catabolism of permethrin ( Baynes et al., 2002; Choi

  3. Nickel-mediated radioiodination of aryl and heteroaryl bromides: rapid synthesis of tracers for SPECT imaging.

    Science.gov (United States)

    Cant, Alastair A; Champion, Sue; Bhalla, Rajiv; Pimlott, Sally L; Sutherland, Andrew

    2013-07-22

    Rapid and efficient radioiodination of aryl and heteroaryl bromides has been achieved using a nickel(0)-mediated halogen-exchange reaction. This transformation gives direct access to [(123)I]- and [(125)I]-imaging agents for single photon emission computed tomography (SPECT), such as 5-[(123)I]-A85380 (see scheme, Boc = tert-butyloxycarbonyl, cod = 1,5-cyclooctadiene, TFA = trifluoroacetic acid). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Synthesis of dimethyl aryl acylsulfonium bromides from aryl methyl ketones in a DMSO-HBr system.

    Science.gov (United States)

    Cao, Zhiling; Shi, Dahua; Qu, Yingying; Tao, Chuanzhou; Liu, Weiwei; Yao, Guowei

    2013-12-16

    A new, simplified method for the synthesis of dimethyl aryl acylsulfonium salts has been developed. A series of dimethyl aryl acylsulfonium bromides were prepared by the reaction of aryl methyl ketones with hydrobromic acid and dimethylsulfoxide (DMSO). This sulfonium salt confirms that bromine production and the bromination reaction take place in the DMSO-HBr oxidation system. What's more, it is also a key intermediate for the synthesis of arylglyoxals.

  5. Synthesis of Dimethyl Aryl Acylsulfonium Bromides from Aryl Methyl Ketones in a DMSO-HBr System

    Directory of Open Access Journals (Sweden)

    Zhiling Cao

    2013-12-01

    Full Text Available A new, simplified method for the synthesis of dimethyl aryl acylsulfonium salts has been developed. A series of dimethyl aryl acylsulfonium bromides were prepared by the reaction of aryl methyl ketones with hydrobromic acid and dimethylsulfoxide (DMSO. This sulfonium salt confirms that bromine production and the bromination reaction take place in the DMSO-HBr oxidation system. What’s more, it is also a key intermediate for the synthesis of arylglyoxals.

  6. Pd-catalyzed decarboxylative cross coupling of potassium polyfluorobenzoates with aryl bromides, chlorides, and triflates.

    Science.gov (United States)

    Shang, Rui; Xu, Qing; Jiang, Yuan-Ye; Wang, Yan; Liu, Lei

    2010-03-05

    Pd-catalyzed decarboxylative cross coupling of potassium polyfluorobenzoates with aryl bromides, chlorides, and triflates is achieved by using diglyme as the solvent. The reaction is useful for synthesis of polyfluorobiaryls from readily accessible and nonvolatile polyfluorobenzoate salts. Unlike the Cu-catalyzed decarboxylation cross coupling where oxidative addition is the rate-limiting step, in the Pd-catalyzed version decarboxylation is the rate-limiting step.

  7. Replacing conventional carbon nucleophiles with electrophiles: nickel-catalyzed reductive alkylation of aryl bromides and chlorides.

    Science.gov (United States)

    Everson, Daniel A; Jones, Brittany A; Weix, Daniel J

    2012-04-11

    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, -SO(2)Me), 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 (-SnMe(3)), and organosilicon (-SiMe(2)OH) 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. © 2012 American Chemical Society

  8. Copper(I)-catalyzed aryl bromides to form intermolecular and intramolecular carbon-oxygen bonds.

    Science.gov (United States)

    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.

  9. Aminomethylations via Cross-Coupling of Potassium Organotrifluoroborates with Aryl Bromides

    Science.gov (United States)

    Sandrock, Deidre L.

    2008-01-01

    The Suzuki-Miyaura cross-coupling reaction of N,N-dialkylaminomethyltrifluoroborates with aryl halides allows the construction of an aminomethyl aryl linkage through a disconnection based on dissonant reactivity patterns. A variety of these aminomethyltrifluoroborate substrates were prepared in good to excellent yields and then shown to cross-couple with equal facility to both electron-rich and electron-poor aryl halides as well as to a variety of heteroaromatic bromides. PMID:17367156

  10. Eco-friendly synthesis of 2-substituted benzothiazoles catalyzed by cetyltrimethyl ammonium bromide (CTAB) in water

    OpenAIRE

    Yang, Xiao-Liang; Xu, Chun-Mei; Lin,Shao-Miao; Chen,Jiu-Xi; Ding,Jin-Chang; Wu,Hua-Yue; Su,Wei-Ke

    2010-01-01

    A series of 2-substituted benzothiazoles have been synthesized by the condensation of 2-aminothiophenol with aldehydes (RCHO: R = Alkyl, Aryl, Heteroaryl, 2-Arylformyl) in the presence of a catalytic amount of cetyltrimethyl ammonium bromide (CTAB) "on water" by a one-pot procedure without additional organic solvents and oxidants. Thereinto, 2-alkylbenzothiazoles were synthesized in high yields and 2-arylformylbenzothiazoles were obtained from the condensation of 2-aminothiophenol with arylfo...

  11. Linear free energy relationship in reactions between diphenyl amine and benzyl bromides

    Indian Academy of Sciences (India)

    S Ranga Reddy; P Manikyamba

    2006-05-01

    Rate of reaction between benzyl bromide and diphenyl amine is retarded by electron-donating groups and enhanced by electron-withdrawing groups present on the benzene ring of the substrate. Hammett's reaction constant of the reaction decreases with increase in temperature according to the equation, \\rho = -11.92 + 3.54/ T. Minimal structural effects observed are attributed to the fact that the isokinetic temperature of the reaction is close to the reaction temperature.

  12. Effect of lignocaine, sodium cromoglycate, and ipratropium bromide in exercise-induced asthma

    Science.gov (United States)

    Tullett, WM; Patel, KR; Berkin, KE; Kerr, JW

    1982-01-01

    Eight patients with exercise-induced asthma participated in a single-blind trial comparing the protective effects of inhaled lignocaine (estimated dose 48 mg), sodium cromoglycate (estimated dose 12 mg), and ipratropium bromide (estimated dose 120 μg). Saline was used as control. Effects were assessed from the mean maximal percentage fall in forced expiratory volume in one second (FEV1) and maximal mid-expiratory flow rates (MMFR) after they had run on a treadmill for eight minutes. There was no significant change in baseline FEV1 or MMFR before each agent was given. Saline, lignocaine, and sodium cromoglycate did not alter the mean baseline FEV1 or MMFR significantly. Ipratropium caused bronchodilatation with an increase of 16·3% in the mean FEV1 (p<0·001) and of 43·4% in the mean MMFR (p<0·05). After exercise the maximal percentage falls in FEV1 (means and SEM) after saline, lignocaine, sodium cromoglycate, and ipratropium bromide were 38·1% (5·0), 34·5% (6·1), 11·3% (3·7), and 19·3% (7·4) respectively. Similarly, the mean maximal falls in MMFR after saline, lignocaine, sodium cromoglycate, and ipratropium bromide were 54·4% (5·2), 52·9% (7·7), 23·6% (6·6), and 32·1% (10·5) respectively. The inhibitory effects of sodium cromoglycate and ipratropium bromide were significant whereas lignocaine failed to produce an effect. These results suggest that mediator release is an important factor in exercise-induced asthma and that in some patients the effects of the mediators may be on the postsynaptic muscarinic receptors. Local anaesthesia of sensory vagal receptors, on the other hand, does not prevent exercise asthma and these receptors do not appear to have any important role in exercise-induced bronchoconstriction. PMID:6218645

  13. Bromidotetra-kis-(2-isopropyl-1H-imidazole-κN)copper(II) bromide.

    Science.gov (United States)

    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.

  14. Bromidotetrakis(2-isopropyl-1H-imidazole-κN3copper(II bromide

    Directory of Open Access Journals (Sweden)

    Anna Dołęga

    2011-10-01

    Full Text Available The CuII atom in the title salt, [CuBr(C6H10N24]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.

  15. Comparison of injection drotaverine and injection valethamate bromide on duration and course of labor

    OpenAIRE

    Pradnya Rajendra Changede

    2016-01-01

    Background: Numerous drugs have been used to shorten the active phase of labor. How rationale is it to use these drugs to shorten the active phase of labor? Do they really shorten the duration of labor? What adverse effects do they have on the baby and the mother? These questions were the basis to perform the present study of comparing two of such drugs, injection drotaverine and injection Valethamate bromide with control subjects. Methods: This was a prospective study conducted in a terti...

  16. Nickel-catalyzed cross-electrophile coupling of 2-chloropyridines with alkyl bromides.

    Science.gov (United States)

    Everson, Daniel A; Buonomo, Joseph A; Weix, Daniel J

    2014-01-01

    The synthesis of 2-alkylated pyridines by the nickel-catalyzed cross-coupling of two different electrophiles, 2-chloropyridines with alkyl bromides, is described. Compared to our previously published conditions for aryl halides, this method uses the different, more rigid bathophenanthroline ligand and is conducted at high concentration in DMF solvent. The method displays promising functional group compatibility and the conditions are orthogonal to the Stille coupling.

  17. Influence of the Amino Substituents in the Interaction of Ethidium Bromide with DNA

    OpenAIRE

    Garbett, Nichola C.; Hammond, Nicholas B.; Graves, David E.

    2004-01-01

    A key step in the rational design of new DNA binding agents is to obtain a complete thermodynamic characterization of small molecule-DNA interactions. Ethidium bromide has served as a classic DNA intercalator for more than four decades. This work focuses on delineating the influence(s) of the 3- and 8-amino substituents of ethidium on the energetic contributions and concomitant fluorescent properties upon DNA complex formation. Binding affinities decrease by an order of magnitude upon the rem...

  18. Synthesis of 3-Allyl-4-phosphachromones by Cyclized Coupling of Ethyl o-Hydroxyphenyl(ethynyl)phosphinate with Allyl Bromide

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    3-Allyl-4-phosphachromones as the phosphorus analogues of chromone were firstly prepared in good yields and high regioselectivity by the palladium(Ⅱ)-catalyzed cyclized coupling reaction of ethyl o-hydroxyphenyl(ethynyl)-phosphinate with allyl bromide.

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

    Science.gov (United States)

    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, Horizontal Stacks, 8 Hours or Less

    Science.gov (United States)

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

    Science.gov (United States)

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

    Science.gov (United States)

    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.

  3. 78 FR 68021 - Notice of Affirmation of Addition of a Treatment Schedule for Methyl Bromide Fumigation of...

    Science.gov (United States)

    2013-11-13

    ... species, Ceratitis capitata (Mediterranean fruit fly) and Anastrepha fraterculus (South American fruit fly... bromide treatment schedule to mitigate risk from C. capitata and A. fraterculus, as described in the TED...

  4. Efficient ring-closing metathesis of alkenyl bromides: the importance of protecting the catalyst during the olefin approach.

    Science.gov (United States)

    Gatti, Michele; Drinkel, Emma; Wu, Linglin; Pusterla, Ivano; Gaggia, Fiona; Dorta, Reto

    2010-11-01

    We present the first productive ring-closing metathesis reaction that leads to the construction of cyclic alkenyl bromides. Efficient catalysis employing commercially available Grubbs II catalyst is possible through appropriate modification of the starting bromoalkene moiety.

  5. Recent trends in atmospheric methyl bromide: analysis of post-Montreal Protocol variability

    Directory of Open Access Journals (Sweden)

    S. A. Yvon-Lewis

    2009-03-01

    Full Text Available The atmospheric methyl bromide (CH3Br burden has declined in recent years, in response to the phaseout of agricultural and structural fumigation consumption under the amendments to the Montreal Protocol. The timing and magnitude of this decrease represents an opportunity to examine our current understanding of the CH3Br budget, the phaseout schedule, and recent estimates of interannual variability in biomass burning and global OH. In this study, simulations obtained from a time-dependent global model of atmospheric CH3Br emissions and uptake are compared to observations from the NOAA flask network. The model includes an updated global methyl bromide source inventory that includes biofuel combustion emissions estimated at 6.1±3 Gg yr−1 globally. The phaseout of CH3Br production for agricultural uses began in 1998, concurrent with the pulse in biomass burning associated with the 1998 El Niño. The combined effects of three factors (biomass burning, global OH, and anthropogenic phaseout appear to explain most of the observed atmospheric methyl bromide trend over the 1997–2005 period. The global budget remains imbalanced, with a large missing source. These results suggest that more than 80% of the missing source does not exhibit significant interannual variability during the phaseout period and, therefore, does not result from underestimating agricultural CH3Br emissions.

  6. Transport of bromide measured by soil coring, suction plates, and lysimeters under transient flow conditions.

    Science.gov (United States)

    Kasteel, R.; Pütz, Th.; Vereecken, H.

    2003-04-01

    Lysimeter studies are one step within the registration procedure of pesticides. Flow and transport in these free-draining lysimeters do not reflect the field situation mainly because of the occurence of a zone of local saturation at the lower boundary (seepage face). The objective of this study is to evaluate the impact of flow and transport behaviour of bromide detected with different measuring devices (lysimeters, suction plates, and soil coring) by comparing experimental results with numerical simulations in heterogeneous flow domains. We applied bromide as a small pulse to the bare soil surface (Orthic Luvisol) of the three devices and the displacement of bromide was regurlarly sampled for three years under natural wheather conditions. Based on the mean breakthrough curves we observe experimentally that lysimeters have a lower effective pore-water velocity and exhibit more solute spreading resulting in a larger dispersivity than the suction plates. This can be ascribed to the artefact of the lower boundary. We performed numerical transport simulations in 2-D heterogeneous flow fields (scaling approach) choosing appropriate boundary conditions for the various devices. The simulations allow to follow the temporal evolution of flow and transport processes in the various devices and to gain additional process understanding. We conclude that the model is essentially capable to reproduce the main experimental findings only if we account for the spatial correlation structure of the hydraulic properties, i.e. soil heterogeneity.

  7. A bio-product as alternative to methyl bromide for replant disease control on strawberry

    Institute of Scientific and Technical Information of China (English)

    Yu ZHANG; Tongle HU; Lijing JI; Keqiang CAO

    2008-01-01

    Pre-plant soil fumigation with methyl bromide (MB) is a standard practice for controlling soil-borne diseases especially for strawberry diseases. However, the application of MB will be forbidden in China in the year 2015. For this reason, a bio-product named Kangdi 3 was tested as an alternative to MB in strawberry greenhouses in Mancheng (Hebei Province) and Donggang (Liaoning province), China in 2005 and 2006. Methyl bromide at a normal dosage of 500 kg/hm2 and Kangdi 3 at three dosages of 750, 1500 and 2250 kg/hm2 were tested. Plots without any treatment were used as the control. During the growing stage, assessments were made on fungal communities in rhizosphere, growth status of strawberry, the disease levels on roots as well as the yields. Results showed that Kangdi 3 significantly reduced the quantity of fungi and the disease index, while enhancing strawberry growth and the yields compared with the untreated control. Therefore, Kangdi 3 is a great potential substitute for methyl bromide to control replant diseases in strawberry.

  8. Interaction of ozone and carbon dioxide with polycrystalline potassium bromide and its atmospheric implication

    Science.gov (United States)

    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- .

  9. The influence of ipratropium bromide and sodium cromoglycate on benzalkonium chloride-induced bronchoconstriction in asthma.

    Science.gov (United States)

    Miszkiel, K A; Beasley, R; Holgate, S T

    1988-01-01

    1. Benzalkonium chloride, an antibacterial preservative that is added to nebuliser solutions, has been shown to cause bronchoconstriction when inhaled by asthmatic subjects. 2. To investigate the potential role of reflex and mast cell-dependent mechanisms in the pathogenesis of bronchoconstriction produced by benzalkonium chloride we examined the effects of ipratropium bromide and sodium cromoglycate on this response in both concentration-response and time-course studies in nine asthmatic subjects. 3. Pretreatment with inhaled ipratropium bromide (1 mg) and sodium cromoglycate (40 mg) displaced the benzalkonium chloride concentration-response curves to the right by a mean 2.2 fold and 3.1 fold respectively. 4. Ipratropium bromide and sodium cromoglycate markedly attenuated the airway response to benzalkonium chloride throughout the 45 min time course period, inhibiting the overall response by 56% and 78% respectively. 5. We conclude that benzalkonium chloride provokes bronchoconstriction in asthmatic subjects through a combination of mast cell activation and stimulation of peripheral and central neural pathways. PMID:2972308

  10. Enhancement of Pool Boiling Heat Transfer to Lithium Bromide Aqueous Solution

    Science.gov (United States)

    Furukawa, Masahiro; Kaji, Masuo; Suyama, Takayuki; Sekoguchi, Kotohiko

    An experimental study on enhancement of nucleate pool boiling heat tranfer by placing a sponge metal close to a plain heated surface was conducted in order to improve the heat transfer performance of the high temperature generator of absorption chiller/heater. The sponge metal has three dimensional porous mesh framework like sponge. Boiling curves of water under the atmospheric pressure were compared with those of lithium bromide aqueous solution of mass concentration 55 to 58%. Heat transfer characteristics were improved by 2 to3 times both for water and lithium bromide aqueous solution when the sponge metal was placed on the heated surface with and without cleareance. Three kinds of sponge metals were used for lithium bromide aqueous solution under the reduced pressure (24 kPa). At lower heat fluxes,#6 sponge metal which has the finest mesh and the lowest porosity shows excellent results. At high heat fluxes, however,it causes deterioration of heat transfer. Over the wide range of heat fluxes,# 4 sponge metal was found to be most suitable and the optimal clearence was determined as 0.5 mm. The sponge metal is of good practical use as a device to enhance the boiling, since no special manufacturing is required for placing it on the heated surface.

  11. Replacing methyl bromide in annual strawberry production with glucosinolate-containing green manure crops.

    Science.gov (United States)

    Lazzeri, Luca; Baruzzi, Gianluca; Malaguti, Lorena; Antoniacci, Loredana

    2003-09-01

    The use of biocidal green manure crops is an agronomic technique for amending soil with fresh organic matter containing volatile compounds active in controlling some soil-borne pests and diseases. Two new selections of the Brassicaceae family were cultivated, incorporated before planting strawberries and tested as an alternative to fumigation with methyl bromide. Two biocidal green manure crops (Brassica juncea L sel ISCI20, Eruca sativa Mill cv Nemat) containing glucosinolate-myrosinase systems, a conventional green manure (barley), untreated soil and a fumigated control were evaluated during two seasons. The effect of these soil management systems on subsequent strawberry performance was evaluated by monitoring yield and plant growth parameters. In both years, biocidal plant green manure treatments led to a fruit yield lower than with methyl bromide, but higher than with conventional green manure or untreated soil. These results confirm the good prospects for biocidal green manures, not only as an environmentally friendly alternative to methyl bromide in conventional agriculture, but also in organic agriculture as an alternative to conventional green manure crops.

  12. Toxic impact of bromide and iodide on drinking water disinfected with chlorine or chloramines.

    Science.gov (United States)

    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.

  13. The Effect of Ozonation Process on Bromide-Containing Groundwaters in Bandung Area and Its Surroundings

    Directory of Open Access Journals (Sweden)

    Mindriany Syafila

    2012-11-01

    Full Text Available Disinfection process was applied as the last step of the water treatment to kill pathogenic bacteria in the water. However, according to several studies, the ozonation disinfection process could form undesired by-products. One of the by-products potentially affecting human life is bromate produced from bromide ionic-containing water. This study was carried out to examine the effect of raw water characteristics and pH on bromate formation. Also, the performance of bromate formation for a period of exposure time was analyzed. Raw waters taken from four different areas around Bandung were exposed to ozone introduced to a reactor with a flow rate of 2 L/min. The pH of the raw waters varied from 4, 7 to 10. The results show that there was no evidence of an initial bromide ion concentration, whereas a change in pH value gives a significantly different outcome. In acidic condition (pH of 4 the bromate formation tends to decrease, whereas when the pH value increases to a pH of 10, the bromate formation increases. Therefore, for drinking water with a neutral pH, when bromide ions are detected in the raw water, the drinking water may be toxic due to the presence of bromate.

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

    Directory of Open Access Journals (Sweden)

    Budnik Lygia T

    2012-01-01

    Full Text Available Abstract 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

  15. Polyvinylpyrrolidone-bromine complex: An efficient polymeric reagent for selective preparation of benzyl bromides in the presence of hexamethyldisilane

    Directory of Open Access Journals (Sweden)

    Moslem M. Lakouraj

    2012-08-01

    Full Text Available Benzylic bromides were conveniently obtained in high yields via the reaction of the corresponding alcohols with crosslinked polyvinylpyrrolidone-bromine complex (PVPP-Br2/hexamethyldisilane in chloroform at reflux condition. Selective conversion of benzyl alcohol to benzyl bromide in the presence of primary aliphatic alcohols, e.g. 2-phenylethanol was also achieved.DOI: http://dx.doi.org/10.4314/bcse.v26i2.14

  16. A general synthesis of fluoroalkylated alkenes by palladium-catalyzed Heck-type reaction of fluoroalkyl bromides.

    Science.gov (United States)

    Feng, Zhang; Min, Qiao-Qiao; Zhao, Hai-Yang; Gu, Ji-Wei; Zhang, Xingang

    2015-01-19

    An efficient palladium-catalyzed Heck-type reaction of fluoroalkyl halides, including perfluoroalkyl bromides, trifluoromethyl iodides, and difluoroalkyl bromides, has been developed. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, and provides a general and straightforward access to fluoroalkylated alkenes which are of interest in life and material sciences. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Palladium-catalyzed carbonylation reactions of aryl bromides at atmospheric pressure: a general system based on Xantphos.

    Science.gov (United States)

    Martinelli, Joseph R; Watson, Donald A; Freckmann, Dominique M M; Barder, Timothy E; Buchwald, Stephen L

    2008-09-19

    A method for the Pd-catalyzed carbonylation of aryl bromides has been developed using Xantphos as the ligand. This method is effective for the direct synthesis of Weinreb amides, primary and secondary benzamides, and methyl esters from the corresponding aryl bromides at atmospheric pressure. In addition, a putative catalytic intermediate, (Xanphos)Pd(Br)benzoyl, was prepared and an X-ray crystal structure was obtained revealing an unusual cis-coordination mode of Xantphos in this palladium-acyl complex.

  18. Dysprosium selective potentiometric membrane sensor

    Energy Technology Data Exchange (ETDEWEB)

    Zamani, Hassan Ali, E-mail: haszamani@yahoo.com [Department of Applied Chemistry, Mashhad Branch, Islamic Azad University, Mashhad (Iran, Islamic Republic of); Faridbod, Farnoush; Ganjali, Mohammad Reza [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of)

    2013-03-01

    A novel Dy(III) ion-selective PVC membrane sensor was made using a new synthesized organic compound, 3,4-diamino-N Prime -((pyridin-2-yl)methylene)benzohydrazide (L) as an excellent sensing element. The electrode showed a Nernstian slope of 19.8 {+-} 0.6 mV per decade in a wide concentration range of 1.0 Multiplication-Sign 10{sup -6}-1.0 Multiplication-Sign 10{sup -2} mol L{sup -1}, a detection limit of 5.5 Multiplication-Sign 10{sup -7} mol L{sup -1}, a short conditioning time, a fast response time (< 10 s), and high selectivity towards Dy(III) ion in contrast to other cations. The proposed sensor was successfully used as an indicator electrode in the potentiometric titration of Dy(III) ions with EDTA. The membrane sensor was also applied to the F{sup -} ion indirect determination of some mouth washing solutions and to the Dy{sup 3+} determination in binary mixtures. Highlights: Black-Right-Pointing-Pointer The novelty of this work is based on the high affinity of the ionophore toward the Dy{sup 3+} ions. Black-Right-Pointing-Pointer This technique is very simple, fast and inexpensive and it is not necessary to use sophisticated equipment. Black-Right-Pointing-Pointer The newly developed sensor is superior to the formerly reported Dy{sup 3+} sensors in terms of selectivity.

  19. The magnetocaloric effect in dysprosium

    Science.gov (United States)

    Benford, S. M.

    1979-01-01

    The magnetocaloric effect in polycrystalline Dy was measured in the 84-280-K range in measuring fields from 1 to 7 T. These adiabatic temperature changes reflect structural changes in Dy with applied field and temperature, and include the first magnetocaloric data for a helical antiferromagnet. Above the Neel point (179 K) a field increase always caused heating; below the Neel point fields less than about 2 T cause cooling for some values of initial temperature. The largest temperature increase with a 7 T field occurs at the Neel point and at fields below 2 T near the Curie point. For refrigeration purposes the optimal working region for a Dy cooling element is field dependent.

  20. Removal of bromide from aqueous solutions using the UV/ZnO process based on the multivariate analysis model

    Directory of Open Access Journals (Sweden)

    Kolsoom Mohammad Moradi

    2017-02-01

    Full Text Available Background: Bromide is found naturally in groundwater and surface water. The rapid growth of industrial activities, drainage of surface runoff, and use of methyl bromide in pesticides has increased bromide discharge to the environment. Disinfection of water-containing bromide causes the creation of additional products of organo-halogenated that are considered cancer-causing agents. In this study, the effect and optimization of factors in removal of this ion was evaluated by using the nano-photocatalytic UV/ZnO process. Methods: This analytical study was conducted in a batch system by the phenol-red method. The test design was performed through the analysis model of multi-factor variance with 99 subjects, while the main, interactive, and reciprocal effects of variables, such as reaction time, catalyst concentration, bromide concentration, and pH at different levels of each factor, were analysed by using SPSS version 16. Results: The main, interactive, and reciprocal effects of factors were significant in three different levels with P < 0.001, and the optimal level of the factors reaction time, catalyst concentration, bromide concentration, and pH were 120 minutes, 0.5, 0.1, and 7 mg/L, respectively, by using the Schaffer test. The highest removal efficiency of 95% was obtained at least 91.56 and a maximum of 94.76% was obtained under optimal conditions of all factors. Conclusion: The results show that by optimization of factors, this process can be effectively used to remove bromide from aquatic environments.

  1. Enhanced degradation of the volatile fumigant-nematicides 1,3-d and methyl bromide in soil.

    Science.gov (United States)

    Ou, L T

    1998-03-01

    The use of the gaseous funaigant-nematicide methyl bromide in agriculture is scheduled to be phased out in the year 2001.1,3-Dichloropropene (1,3-D) in combination with chloropicrin and an herbicide is considered to be a viable alternative to methyl bromide for some crops. 1,3-Dichloropropene consists of two isomers, cis- and trans-l,3-D. A number of soil bacteria have been shown to initially degrade 1,3-D or one of its isomers, cis-l,3-D, via hydrolysis. Until recently, the degradation of cis- and trans-l,3-D in soils was considered to exhibit similar kinetics, witla their degradation rates increasing with increases in soil temperature. Enhanced degradation of 1,3-D in soil from a site in Florida with a history of repeated annual applications of 1,3-D was observed in 1994. Biological hydrolysis was involved in the initial degradation of cis- and trans-l,3-D. The two isomers were degraded at different rates, with the trans isomer being degraded more rapidly than the cis isomer. Cis- and trans-l,3-D in soil from the control site were degraded at a similar rate but more slowly than in the enhanced soil. Methyl bromide in soils can be degraded through chemical hydrolysis and methylation to soil organic matter. Some methanotrophic bacteria and ammonia-oxidation bacteria during the oxidation of their primary substrates (methane and ammonia) also have the capacity to cooxidize methyl bromide to formaldehyde and bromide ion. It was recently observed that degradation of methyl bromide was stimulated in methanotrophic soils and in soils treated with ammonium sulfate. Soil methanotrophic bacteria and soil nitrifiers are apparently responsible for cooxidation of methyl bromide in methanotrophic and ammonia treated soils, respectively.

  2. ACCIDENTAL SUBCUTANEOUS INJECTION OF VECURONIUM BROMIDE IN A PATIENT WITH BURNS

    Directory of Open Access Journals (Sweden)

    Usha Dev

    2014-10-01

    Full Text Available BACKGROUND AND OBJECTIVES: In patients with burn injury drug pharmacology will be altered and this poses special anaesthetic challenge when an subcutaneous injection of a non- depolarizing muscle relaxant occurs in such a patient. Small studies remain an important source of knowledge and hence this study aims to provide information on the anaesthetic management in a case of accidental subcutaneous injection of vecuronium bromide in a burns patient. PRESENTATION, DIAGNOSIS & MANAGEMENT: A 22 year young male with 4 days old hot water induced grade 1 burns involving 45% of body surface area was posted for burns dressing. Anaesthesia was induced with propofol and vecuronium bromide through an external jugular vein to aid tracheal intubation. As the patient was not anaesthetized even after 10 minutes routine check lead to the discovery of fullness at the tip of the intravenous catheter indicating an extravasation of the drugs. Hence the other external jugular vein was cannulated and the patient induced and intubated using propofol, sevoflurane, nitrous oxide and oxygen. The action of vecuronium outlasted the duration of surgery. So the patient continued to receive support of mechanical ventilation with nitrous oxide and oxygen. It took 130 minutes for the clinical signs of recovery from the muscle relaxant to manifest. He was then reversed & extubated with subsequent good recovery. CONCLUSION: Subcutaneous injection of these drugs poses problems of delayed onset of action and prolonged duration of action. In an inadvertent accidental subcutaneous 0.1 mg/kg vecuronium bromide injection in a patient with 4 day old 45% burns showed delayed onset action and prolonged neuromuscular blockade due to subcutaneous deposition of the drug which was managed with mechanical ventilation .The reported resistance to the action of NDMR drugs in patient with burns was not noticed here probably because of the age of the thermal injury.

  3. Ethidium bromide-induced demyelination of the sciatic nerve of adult Wistar rats

    Directory of Open Access Journals (Sweden)

    Riet-Correa G.

    2002-01-01

    Full Text Available Peripheral nerve ultrastructure was assessed after single or multiple local injections of the intercalating dye ethidium bromide. Thirty-four adult Wistar rats of both sexes were divided into five groups and maintained in a controlled environment with rat chow and water ad libitum throughout the experiment. The experimental animals were injected with 1 µl of 0.1% ethidium bromide in 0.9% saline into the central third of the left sciatic nerve 1 (group 1, 2 (group 2, 4 (group 3, 6 (group 4 or 8 (group 5 times. In groups 2 to 5 the injections were made at 28-day intervals. Control animals received the same amount of 0.9% saline. The animals were killed at different times after injection: group 1 at 7 days (2 rats and 15 days (2 rats; for groups 2, 3, 4 and 5, all rats were killed 10 days after the last injection and the lesions were investigated by light and transmission electron microscopy. In the acute lesions, intoxicated Schwann cells showed a vacuolated cytoplasm and separation of the sheaths from the axon. Myelin sheaths underwent progressive vesiculation and subsequent segmental demyelination. Myelin debris were withdrawn by macrophages and remyelination by Schwann cells was prominent. With the increase in the number of injections collagen fibers also increased in number and progressively enveloped smaller numbers of remyelinated axons composing new fascicles. Wallerian degeneration of fibers apparently not affected by ethidium bromide was more intense in the nerves from groups 4 and 5. The peripheral nerve repairs itself after demyelinating challenges with a profusion of collagen fibers and new fasciculations. This experimental model is valid to mimic recurrent demyelinating neuropathies.

  4. Measurement and computation of movement of bromide ions and carbofuran in ridged humic-sandy soil.

    Science.gov (United States)

    Leistra, Minze; Boesten, Jos J T I

    2010-07-01

    Water flow and pesticide transport in the soil of fields with ridges and furrows may be more complex than in the soil of more level fields. Prior to crop emergence, the tracer bromide ion and the insecticide carbofuran were sprayed on the humic-sandy soil of a potato field with ridges and furrows. Rainfall was supplemented by sprinkler irrigation. The distribution of the substances in the soil profile of the ridges and furrows was measured on three dates in the potato growing season. Separate ridge and furrow systems were simulated by using the pesticide emission assessment at regional and local scales (PEARL) model for pesticide behavior in soil-plant systems. The substances travelled deeper in the furrow soil than in the ridge soil, because of runoff from the ridges to the furrows. At 19 days after application, the peak of the bromide distribution was measured to be in the 0.1-0.2 m layer of the ridges, while it was in the 0.3-0.5 m layer of the furrows. After 65 days, the peak of the carbofuran distribution in the ridge soil was still in the 0.1 m top layer, while the pesticide was rather evenly distributed in the top 0.6 m of the furrow soil. The wide ranges in concentration measured with depth showed that preferential water flow and substance transport occurred in the sandy soil. Part of the bromide ion distribution was measured to move faster in soil than the computed wave. The runoff of water and pesticide from the ridges to the furrows, and the thinner root zone in the furrows, are expected to increase the risk of leaching to groundwater in ridged fields, in comparison with more level fields.

  5. Otilonium bromide inhibits muscle contractions via L-type calcium channels in the rat colon.

    Science.gov (United States)

    Martin, M T; Hove-Madsen, L; Jimenez, M

    2004-04-01

    The aim of this study is to evaluate in vitro the effect of otilonium bromide (OB) on the mechanical and electrical activities of the rat colonic smooth muscle using muscle bath, microelectrodes and patch-clamp techniques. Otilonium bromide dose dependently inhibited the spontaneous activity (logIC(50) +/- SE: -5.31 +/- 0.05). This effect was not modified by TTX (10(-6) mol L(-1)). Cyclic depolarizations were abolished by OB (10(-4) mol L(-1)). Electrical field stimulation induced inhibitory junction potentials (IJPs) followed by a depolarization with superimposed spikes causing a contraction. In the presence of OB (10(-4) mol L(-1)) IJPs were recorded, but spikes and contractions were abolished. Otilonium bromide (3 x 10(-6) mol L(-1)) inhibited inward current obtained in isolated cells (amphotericin perforated patch technique). The otilonium-sensitive current amplitude was maximal (75pA) around 0 mV. The effect of different doses of OB was tested by depolarizing cells from -70 mV to 0 mV. OB dose dependently inhibited the inward current with an EC(50) of 885 nmol L(-1). Abolishment of the otilonium-sensitive current by 3 x 10(-6) mol L(-1) nifedipine confirmed that it was an L-type Ca(2+) current. Our results show that OB inhibits the spontaneous and triggered muscular contractions. This effect is produced by the inhibition of muscular action potentials carried by L-type calcium current, confirming the spasmolytic properties of OB.

  6. Effect of otilonium bromide on contractile patterns in the human sigmoid colon.

    Science.gov (United States)

    Gallego, D; Aulí, M; Aleu, J; Martínez, E; Rofes, L; Martí-Ragué, J; Jiménez, M; Clavé, P

    2010-06-01

    The mechanism of action of the spasmolytic compound otilonium bromide (OB) on human colonic motility is not understood. The aim of our study was to characterize the pharmacological effects of OB on contractile patterns in the human sigmoid colon. Circular sigmoid strips were studied in organ baths. Isolated smooth muscle cells from human sigmoid colon were examined using the calcium imaging technique. Otilonium bromide inhibited by 85% spontaneous non-neural rhythmic phasic contractions (RPCs), (IC(50) = 49.9 nmol L(-1)) and stretch-induced tone (IC(50) = 10.7 nmol L(-1)) with maximum effects at micromolar range. OB also inhibited by 50% both on- (IC(50) = 38.0 nmol L(-1)) and off-contractions induced by electrical stimulation of excitatory motor neurons. In contrast, the inhibitory latency period prior to off-contractions was unaffected by OB. OB inhibited acetylcholine-, substance P-, and neurokinin A-induced contractions. The L-type Ca(2+) channel agonist BayK8644 reversed the effects of OB on RPCs, on- and off-contractions. Hexamethonium, atropine, the NK(2) antagonist, or depletion of intracellular Ca(2+) stores by thapsigargin did not prevent the inhibitory effect of OB on RPCs and electrical contractions. KCl-induced calcium transients in isolated smooth muscle cells were also inhibited by OB (IC(50) = 0.2 micromol L(-1)). Otilonium bromide strongly inhibited the main patterns of human sigmoid motility in vitro by blocking calcium influx through L-type calcium channels on smooth muscle cells. This pharmacological profile may mediate the clinically observed effects of the drug in patients with irritable bowel syndrome.

  7. COMPARISION OF ROCURONIUM BROMIDE AND SUXAMETHONIUM CHLORIDE FOR USE DURING RAPID SEQUENCE INDUCTION OF ANAESTHESIA

    Directory of Open Access Journals (Sweden)

    Sarita

    2015-12-01

    Full Text Available AIM To evaluate the quality of intubating conditions with Suxamethonium chloride and Rocuronium bromide for rapid sequence induction intubation and to observe the correlation between the intubating conditions and the response to single twitch stimulation. MATERIALS AND METHODS The present study, entitled “Comparison of Rocuronium bromide and Suxamethonium chloride for use during rapid sequence induction of anaesthesia was done in 50 adult patients divided into two groups and were randomly allocated Group-I: IV Rocuronium 0.9mg/kg and Group-II: IV Suxamethonium 1mg/kg. Laryngoscopy was attempted at 60 sec. and assessment of quality of intubating conditions was performed by using a Viby Mogensen Scale. Neuromuscular monitor was used to observe the correlation between the intubating conditions and the adductor pollicis response to single twitch ulnar nerve stimulation. RESULTS Intubating conditions were excellent (Score 15 in 88% of cases in Group-I whereas vocal cord position was intermediate (10- 14 in 12% of cases, in Group-II all cases could be intubated at 60 sec. (Score 15 in 100% cases. The onset of maximal blockade at adductor pollicis was found to correlate well with satisfactory intubating conditions in Group-II (Sch whereas in 20% of patients in Group-I had single twitch response (though diminished at the time of intubation. CONCLUSION Rocuronium bromide in dose of 0.9mg/kg provided neuromuscular blockade with a fast onset time and good to excellent intubating conditions at 60 sec. resembling those of Suxamethonium.

  8. [Efficacy of glycopyrronium bromide and scopolamine hydrobromide in patients with death rattle: a randomized controlled study].

    Science.gov (United States)

    Likar, Rudolf; Rupacher, Ernst; Kager, Hans; Molnar, Mario; Pipam, Wofgang; Sittl, Reinhard

    2008-01-01

    Death rattle is an extremely distressing symptom for the dying patient and for his environment. The aim of this study was to assess the efficacy of glycopyrronium bromide as compared with scopolamine hydrobromide in alleviating death rattle in terminal cancer patients with cognitive impairment. In a randomized, controlled study design patients were allocated in two groups. Group A received scopolamine hydrobromide in a dose of 0.5 mg intravenously every 6 hours for a period of 12 hours, group B received glycopyrronium bromide 0.4 mg every 6 hours for a period of 12 hours. In addition, standardized sedatives were administered as required and the analgesic therapy continued either orally or, if necessary, subcutaneously or intravenously in equipotent doses. Every 2 hours death rattle was assessed and rated on a scale of 1 to 5 (1 = audible breathing noises, 5 = very severe rattling noises). In addition, restlessness and expressions of pain were assessed and rated on a scale of 1 to 3 (1 = mild, 2 = moderate, 3 = severe). 13 patients were included in the study, 7 patients were allocated to group A and 6 patients to group B. There were no significant differences in demographic data, age, weight and diagnosis distribution between the two groups. Group B demonstrated a significant reduction of death rattle in the first 12 hours (p = 0.029) in comparison to group A. There were no significant differences concerning the side effects (restlessness, expressions of pain) in both groups. Glycopyrronium bromide given in a dose of 0,4 mg every six hours demonstrated a significant reduction of death rattle compared to scopolamine hydrobromide. Concerning side effects (restlessness, expressions of pain) there was no difference between both substances.

  9. Inhibition of methoxamine-induced bronchoconstriction by ipratropium bromide and disodium cromoglycate in asthmatic subjects.

    Science.gov (United States)

    Black, J; Vincenc, K; Salome, C

    1985-01-01

    We compared the effects of pretreatment with saline, ipratropium bromide, and disodium cromoglycate (DSCG) on bronchoconstriction induced by methoxamine--an alpha-adrenoceptor agonist, in asthmatic subjects. All 12 patients bronchoconstricted in response to methoxamine after saline. The PD20 (the dose of methoxamine causing a 20% fall in forced expiratory volume in 1 s [FEV1]) ranged from 0.3-18 mumol. Ipratropium bromide (200 micrograms administered by aerosol) significantly inhibited (P less than 0.05) the response to methoxamine in all patients without producing significant changes in the mean baseline lung function. The mean PD20 for methoxamine after saline was 6.8 mumol and 95% confidence limits (CL) were 3.6, 12.7 mumol. The mean PD20 for methoxamine after ipratropium bromide was 35.4 (95% CL 28.8, 43.6) mumol. DSCG also produced significant (P less than 0.05) shifts to the right in the methoxamine dose response curves, but did not affect resting airway calibre as measured by the FEV1. The mean PD20 for methoxamine increased from 3.3 mumol (95% CL 1.1, 10.0 mumol) after saline to 25.1 mumol (95% CL 14.1, 44.6) after DSCG pretreatment. These findings suggest that alpha-adrenoceptors in the airways of asthmatic subjects may be located at sites other than smooth muscle--possibly on mast cells but more likely on nerve endings and/or parasympathetic ganglia. PMID:2992563

  10. Structures, electronic properties and stability phase diagrams for copper(I/II) bromide surfaces.

    Science.gov (United States)

    Altarawneh, Mohammednoor; Marashdeh, Ali; Dlugogorski, Bogdan Z

    2015-04-14

    This study presents a comprehensive periodic slab DFT investigation into structures, electronic properties and thermodynamic stability of all plausible terminations of CuBr and CuBr2 surfaces. We first estimate lattice constants, formation and cohesive energies for the two bulk copper bromides before proceeding to analyse geometrical and electronic features of CuBr and CuBr2 configurations. Surface geometries exhibit, to a large extent, corresponding bulk structures. Nevertheless, certain CuBr2 surfaces experience a downward displacement of the topmost Cu-containing layers. We plot total and projected density of states for bulk and surface geometries of these two copper bromides and calculate their associated Bader's electronic charges. Electronic structure analysis for the bulk and surfaces of these two copper bromides show that CuBr bulk and its most stable surface (CuBr(001)_Br) do not exhibit any metallic character, whereas CuBr2 bulk and its most stable surface (CuBr2(001)_Br) both exhibit metallic characters. The formalism of the ab initio atomistic thermodynamics affords the construction of energy phase diagrams. We predict that the CuBr(001) surface, truncated with Br atoms, is the most stable structure among the considered CuBr slabs at all physically meaningful ranges of the chemical potential of bromine. This surface resembles a c(2 × 2)-bromine sheet that was characterised experimentally from initial interaction of Br2 with a Cu(100) surface. We find that surfaces terminated with the electronegative bromine atoms, if accompanied by significant relaxation, tend to be more stable. Calculated surface energies predict the shapes of CuBr and CuBr2 nanoparticles as the chemical potential of bromine changes.

  11. General method for the preparation of active esters by palladium-catalyzed alkoxycarbonylation of aryl bromides.

    Science.gov (United States)

    de Almeida, Angelina M; Andersen, Thomas L; Lindhardt, Anders T; de Almeida, Mauro V; Skrydstrup, Troels

    2015-02-06

    A useful method was developed for the synthesis of active esters by palladium-catalyzed alkoxycarbonylation of (hetero)aromatic bromides. The protocol was general for a range of oxygen nucleophiles including N-hydroxysuccinimide (NHS), pentafluorophenol (PFP), hexafluoroisopropyl alcohol (HFP), 4-nitrophenol, and N-hydroxyphthalimide. A high functional group tolerance was displayed, and several active esters were prepared with good to excellent isolated yields. The protocol was extended to access an important synthetic precursor to the HIV-protease inhibitor, saquinavir, by formation of an NHS ester followed by acyl substitution.

  12. Biphilic Organophosphorus Catalysis: Regioselective Reductive Transposition of Allylic Bromides via PIII/PV Redox Cycling

    Science.gov (United States)

    Reichl, Kyle D.; Dunn, Nicole L.; Fastuca, Nicholas J.; Radosevich, Alexander T.

    2016-01-01

    We report that a regioselective reductive transposition of primary allylic bromides is catalyzed by a biphilic organophosphorus (phosphetane) catalyst. Spectroscopic evidence supports the formation of a pentacoordinate (σ5-P) hydridophosphorane as a key reactive intermediate. Kinetics experiments and computational modeling are consistent with a unimolecular decomposition of the σ5-P hydridophosphorane via a concerted cyclic transition structure that delivers the observed allylic transposition and completes a novel PIII/PV redox catalytic cycle. These results broaden the growing repertoire of reactions catalyzed within the PIII/PV redox couple and suggest additional opportunities for organophosphorus catalysis in a biphilic mode. PMID:25874950

  13. Synthesis of the Multisubstituted Halogenated Olefins via Cross-Coupling of Dihaloalkenes with Alkylzinc Bromides

    Science.gov (United States)

    Andrei, Daniela

    2008-01-01

    The 1-fluoro-1-haloalkenes undergo Pd-catalyzed Negishi cross-couplings with primary alkylzinc bromides to give multisubstituted fluoroalkenes. The alkylation was trans-selective giving pure Z-fluoroalkenes in most cases. The highest yields were obtained with Pd2(dba)3 and PdCl2(dppb) catalysts but the best stereochemical outcome was obtained with less reactive Pd(PPh3)4. The tertiary alkylzincs also produced desired fluoroalkenes in high yields. Coupling of 1,1-dichloroalkene with organozinc reagent resulted in the formation of mono-coupled product. PMID:16388671

  14. Efficient SN2 fluorination of primary and secondary alkyl bromides by copper(I) fluoride complexes

    KAUST Repository

    Liu, Yanpin

    2013-11-11

    Copper(I) fluoride complexes ligated by phenanthroline derivatives have been synthesized and structurally characterized by X-ray crystallography. These complexes adopt as either ionic or neutral forms in the solid state, depending on the steric bulkiness of the substituent groups on the phenanthroline ligands. These complexes react with primary and secondary alkyl bromides to produce the corresponding alkyl fluorides in modest to good yields. This new method is compatible with a variety of important functional groups such as ether, thioether, amide, nitrile, methoxyl, hydroxyl, ketone, ester, and heterocycle moieties. © 2013 American Chemical Society.

  15. Cetyltrimethyl ammonium bromide-Mg/Al hydrotalcite for removal phenol in water

    Science.gov (United States)

    Kurniawati, Puji; Wiyantoko, Bayu; Purbaningtias, Tri Esti; Muzdalifah

    2017-03-01

    Hydrotalcite materials was synthesized by using Cetyltrimethyl Ammonium Bromide (CTAB) and Mg/Al layered double hydroxide with ratio molar 3:1. Synthesis of CTAB-Mg/Al hydrotalcite was carried out using ex situ co-precipitation method at pH 10±0.5. Removal of phenol was optimum at medium pH 6 and it had optimum contact time in 300 min. It followed pseudo second order with adsorption rate constant was 1.15.10-4 mM-1.min-1. The maximum adsorption capacities obtained from the Langmuir model was 35.71 mg.g-1 at room temperature.

  16. Copper bromide vapour laser with an output pulse duration of up to 320 ns

    Energy Technology Data Exchange (ETDEWEB)

    Gubarev, F A; Fedorov, K V; Evtushenko, G S [National Research Tomsk Polytechnic University, Tomsk (Russian Federation); Fedorov, V F; Shiyanov, D V [V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk (Russian Federation)

    2016-01-31

    We report the development of a copper bromide vapour laser with an output pulse duration of up to 320 ns. To lengthen the pulse, the discharge current was limited using a compound switch comprising a pulsed hydrogen thyratron and a tacitron. This technique permits limiting the excitation of the working levels at the initial stage of the discharge development to lengthen the inversion lifetime. The longest duration of a laser pulse was reached in tubes 25 and 50 mm in diameter for a pulse repetition rate of 2 – 4 kHz. (lasers and laser beams)

  17. Comparative characteristics of copper, copper chloride, and copper bromide vapor lasers

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian, M.A.; Petrash, G.G.; Trofimov, A.N.

    1980-03-01

    The paper reports the results of a comparative study of copper and copper halide vapor lasers emitting in a repetitively-pulsed regime. Copper chloride and copper bromide vapor lasers are found to have identical lasing characteristics under any excitation conditions. These characteristics are different from those of a copper vapor laser. An average lasing power of 13 W has been obtained for all lasers studied for an efficiency of 1%. It is shown that the choice of a laser will largely depend on the laser design suitability for a specific application.

  18. Eco-friendly synthesis of 2-substituted benzothiazoles catalyzed by cetyltrimethyl ammonium bromide (CTAB) in water

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiao-Liang; Xu, Chun-Mei; Lin, Shao-Miao; Chen, Jiu-Xi; Ding, Jin-Chang; Wu, Hua-Yue [Wenzhou University (China). College of Chemistry and Materials Engineering; Su, Wei-Ke [Zhejiang University of Technology, Hangzhou (China). College of Pharmaceutical Sciences. Zhejiang Key Laboratory of Pharmaceutical Engineering

    2010-07-01

    A series of 2-substituted benzothiazoles have been synthesized by the condensation of 2-aminothiophenol with aldehydes (RCHO: R = Alkyl, Aryl, Heteroaryl, 2-Arylformyl) in the presence of a catalytic amount of cetyltrimethyl ammonium bromide (CTAB) 'on water' by a one-pot procedure without additional organic solvents and oxidants. Thereinto, 2-alkylbenzothiazoles were synthesized in high yields and 2-arylformylbenzothiazoles were obtained from the condensation of 2-aminothiophenol with arylformyl aldehydes for the first time using the present protocol. (author)

  19. Vapour pressure and enthalpy of aqueous lithium bromide solutions. [Used in absorption heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A.; Patwardhan, V.S. (National Chemical Lab., Poona (India))

    1992-07-01

    In this paper we present new equations for accurate calculations of the vapour pressure and enthalpy of aqueous lithium bromide solutions which are commonly used in absorption heat pumps and absorption heat transformers. The number of empirical parameters involved in these equations is much smaller than those in earlier equations. Moreover, the present equations for both vapour pressure and enthalpy involve the same constants as both these equations are derived from a single free energy equation using standard thermodynamic concepts. The present methodology can be used with any other electrolyte for which enthalpy-concentration diagrams may not be readily available. (Author).

  20. Improved detection of rhamnolipid production using agar plates containing methylene blue and cetyl trimethylammonium bromide.

    Science.gov (United States)

    Pinzon, Neissa M; Ju, Lu-Kwang

    2009-10-01

    Rhamnolipids, produced predominantly by Pseudomonas aeruginosa, are biosurfactants with important applications. For efficient culture screening according to rhamnolipid productivity, the method using agar plates containing methylene blue (MB) and cetyl trimethylammonium bromide (CTAB) was re-examined. An alternative set-up using a fixed underneath light source and image analysis software improved the detection of the circles formed due to complexation between anionic rhamnolipids and cationic MB/CTAB. The roles and effects of MB and CTAB concentrations and pH on the complexation phenomena are reported.

  1. Thermal and optical studies of some di-methyl-di-alkyl ammonium bromides

    Science.gov (United States)

    Witko, Waclaw; Godlewska, Malgorzata; Dynarowicz, Patrycja

    1998-01-01

    Phase situation of homologous series of di-alkyl-di-methyl ammonium bromides represented by the general formula: 2CnN+2C1Br-, with n equals 10, 12, 14, 16, 18, was investigated by means of differential scanning calorimetry and optical microscopy methods in the temperature range 20-180 degrees C. A more complex polymorphism as already reported was detected. All the compounds studied show at least tow anomalies on the DSC curves. The high-temperature phase which appears below the isotropic phase has lancet-like dendritic texture which can be attributed to SmB phase. The enthalpy changes at the transitions were calculated.

  2. Nitrate ion photolysis in thin water films in the presence of bromide ions.

    Science.gov (United States)

    Richards, Nicole K; Wingen, Lisa M; Callahan, Karen M; Nishino, Noriko; Kleinman, Michael T; Tobias, Douglas J; Finlayson-Pitts, Barbara J

    2011-06-16

    Nitrate ions commonly coexist with halide ions in aged sea salt particles, as well as in the Arctic snowpack, where NO(3)(-) photochemistry is believed to be an important source of NO(y) (NO + NO(2) + HONO + ...). The effects of bromide ions on nitrate ion photochemistry were investigated at 298 ± 2 K in air using 311 nm photolysis lamps. Reactions were carried out using NaBr/NaNO(3) and KBr/KNO(3) deposited on the walls of a Teflon chamber. Gas phase halogen products and NO(2) were measured as a function of photolysis time using long path FTIR, NO(y) chemiluminescence and atmospheric pressure ionization mass spectrometry (API-MS). Irradiated NaBr/NaNO(3) mixtures show an enhancement in the rates of production of NO(2) and Br(2) as the bromide mole fraction (χ(NaBr)) increased. However, this was not the case for KBr/KNO(3) mixtures where the rates of production of NO(2) and Br(2) remained constant over all values of χ(KBr). Molecular dynamics (MD) simulations show that the presence of bromide in the NaBr solutions pulls sodium toward the solution surface, which in turn attracts nitrate to the interfacial region, allowing for more efficient escape of NO(2) than in the absence of halides. However, in the case of KBr/KNO(3), bromide ions do not appreciably affect the distribution of nitrate ions at the interface. Clustering of Br(-) with NO(3)(-) and H(2)O predicted by MD simulations for sodium salts may facilitate a direct intermolecular reaction, which could also contribute to higher rates of NO(2) production. Enhanced photochemistry in the presence of halide ions may be important for oxides of nitrogen production in field studies such as in polar snowpacks where the use of quantum yields from laboratory studies in the absence of halide ions would lead to a significant underestimate of the photolysis rates of nitrate ions.

  3. Cooperative dynamics of didodecyldimethylammonium bromide / water / n-dodecane microemulsions: a dielectric relaxation study

    OpenAIRE

    Wachter, Wolfgang

    2008-01-01

    A systematic study of the dielectric relaxation spectra of W/O (water-in-oil) microemulsions composed of didodecyldimethylammonium bromide (DDAB), water (W) and n-dodecane (D) has been made over the whole stability region in the phase diagram and over a wide range of frequencies (0.005 < nu/GHz < 89) at 25 °C. The spectra were best described by a superposition of six or five Debye processes, respectively, depending on the position of the sample in the phase diagram. Process 1 at 40 ns can be ...

  4. Promotion of hexadecyltrimethyleamine bromide to the damage of Alexandrium sp. LC3 by cupric glutamate

    Institute of Scientific and Technical Information of China (English)

    LI Hao; MIAO Jin-lai; CUI Feng-xia; LI Guang-you

    2006-01-01

    The effect of hexadecyltrimethyleamine bromide (HDTMAB) on the removal of A lexandrium sp. LC3 under cupric glutamate stress was investigated. Toxic effect of cupric glutamate on A lexandrium sp. LC3 was significantly promoted in the presence of HDTMAB, especially at 3.0 cmc of HDTMAB. It was found that the sulfhydryl group content of the cell decreased, while the malonaldehyde content and membrane permeability increased when Alexandrium sp. LC3 was treated with HDTMAB and cupric glutamate complex, compared with cupric glutamate alone. The data suggest that HDTMAB might stimulate the damage of A lexandrium sp. LC3 by enhancing the membrane permeability.

  5. Mixed micelles of benzyldimethyltetradecylammonium chloride with tetradecyltrimethylammonium and tetradecyltriphenylphosphonium bromides: a head group contribution.

    Science.gov (United States)

    Bakshi, Mandeep Singh; Kaur, Ishpinder; Sood, Rohit; Singh, Jasmeet; Singh, Kulbir; Sachar, Shweta; Singh, Kanwar Jit; Kaur, Gurinder

    2004-03-01

    Mixed micelle formation by tetradecyltrimethylammonium (TTAB) and tetradecyltriphenylphosphonium bromides (TTPB) with benzyldimethyltetradecylammonium chloride (BTDACl) was studied with the help of conductivity and Kraft point measurements. The BTDACl + TTAB mixtures showed synergistic interactions whereas those of BTDACl + TTPB indicated weak antagonistic behavior. From Kraft temperature measurements, the enthalpy of fusion (H(1)(0)) from solid hydrated BTDACl to the liquid state in the presence of TTAB or TTPB was computed. It was found that DeltaH(1)(0) was much more positive for BTDACl + TTPB than for BTDACl + TTAB mixtures.

  6. Cytotoxicity evaluation of Clinacanthus nutans through dimethylthiazol diphenyltetrazolium bromide and neutral red uptake assays

    OpenAIRE

    Vajrabhaya, La-ongthong; Korsuwannawong, Suwanna

    2016-01-01

    Objectives: The aim of this study was to compare the results of dimethylthiazol diphenyltetrazolium bromide (MTT) and neutral red uptake (NRU) assays of Clinacanthus nutans cytotoxicity. Materials and Methods: Mouse fibroblast (L929) cells were exposed to 0.01%, 0.1%, 0.25%, and 0.5% (W/V) C. nutans in a 96-cluster-well-culture plate for 24 h. The cell viability after exposure to C. nutans was determined by MTT and NRU assays in separate tissue culture plates. The two assays were compared thr...

  7. Generation, spectroscopy, and structure of cyanoformyl chloride and cyanoformyl bromide, XC(O)CN.

    Science.gov (United States)

    Pasinszki, Tibor; Vass, Gábor; Klapstein, Dieter; Westwood, Nicholas P C

    2012-04-01

    Cyanoformyl chloride and cyanoformyl bromide, XC(O)CN (X = Cl and Br), have been investigated in the gas phase by UV photoelectron and mid-infrared spectroscopies. The ground-state geometries of the neutral molecules have been obtained from quantum-chemical calculations at the B3LYP and CCSD(T) levels using the aug-cc-pVTZ basis set. The individual spectroscopies provide a detailed investigation into the vibrational and electronic character of the molecules and are supported by quantum-chemical calculations. The results are compared to data for structurally and chemically related molecules.

  8. Palladium-catalyzed cross coupling reaction of N-alkoxyimidoyl bromides and its application to one-pot synthesis of N-arylamines.

    Science.gov (United States)

    Ueda, Masafumi; Sugita, Shoichi; Aoi, Naoki; Sato, Aoi; Ikeda, Yuki; Ito, Yuta; Miyoshi, Tetsuya; Naito, Takeaki; Miyata, Okiko

    2011-01-01

    The synthetic utility of N-alkoxyimidoyl halides is demonstrated using the palladium-catalyzed cross-coupling reaction. The Sonogashira and Suzuki-Miyaura coupling reactions of N-alkoxyimidoyl bromides produced versatile ketoxime ethers in good to excellent yields. A one-pot reaction of the imidoyl bromides with arylboronic acid and allylmagnesium bromide to produce N-arylamines via Suzuki-Miyaura coupling followed by domino reaction involving sequential addition-eliminative rearrangement-addition reactions was developed.

  9. p-Bromophenacyl bromide prevents cumene hydroperoxide-induced mitochondrial permeability transition by inhibiting pyridine nucleotide oxidation.

    Science.gov (United States)

    Zhukova, A; Gogvadze, G; Gogvadze, V

    2004-01-01

    Mitochondrial permeability transition is commonly characterized as a Ca2+ -dependent non-specific increase in inner membrane permeability that results in swelling of mitochondria and their de-energization. In the present study, the effect of different inhibitors of phospholipase A2--p-bromophenacyl bromide, dibucaine, and aristolochic acid--on hydroperoxide-induced permeability transitions in rat liver mitochondria was tested. p-Bromophenacyl bromide completely prevented the hydroperoxide-induced mitochondrial permeability transition while the effects of dibucaine or aristolochic acid were negligible. Organic hydroperoxides added to mitochondria undergo reduction to corresponding alcohols by mitochondrial glutathione peroxidase. This reduction occurs at the expense of GSH which, in turn, can be reduced by glutathione reductase via oxidation of mitochondrial pyridine nucleotides. The latter is considered a prerequisite step for mitochondrial permeability transition. Among all the inhibitors tested, only p-bromophenacyl bromide completely prevented hydroperoxide-induced oxidation of mitochondrial pyridine nucleotides. Interestingly, p-bromophenacyl bromide had no affect on mitochondrial glutathione peroxidase, but reacted with mitochondrial glutathione that prevented pyridine nucleotides from being oxidized. Our data suggest that p-bromophenacyl bromide prevents hydroperoxide-induced deterioration of mitochondria via interaction with glutathione rather than through inhibition of phospholipase A2.

  10. The use of anti-spasmodics in the treatment of irritable bowel syndrome: focus on otilonium bromide.

    Science.gov (United States)

    Forte, E; Pizzoferrato, M; Lopetuso, L; Scaldaferri, F

    2012-01-01

    Aim of this review is to summarize the studies carried out, with particular interest in those who dealt with otilonium bromide in treatment of IBS. Irritable bowel syndrome (IBS). IBS is a frequent gastrointestinal disease, characterized by a combination of several symptoms including abdominal pain or discomfort, flatulence and problems related to bowel habits (constipation and/or diarrhea). It affects about 15% of the western population, with a negative impact on the quality of life and also on health care costs. Face to such important complexity and negative impact, therapeutic options are still very limited and most of the pharmacological compounds mostly validated for short term use, are only partially controlling symptoms. Among those, anti-spasmodics are commonly used in clinical settings. Despite a discrete literature in support of these drugs, systematic collections of clinical evidence to support the use of anti-spasmodics and in particular the use of otilonium bromide in course of IBS are scarce. Otilonium bromide is a systemically poorly absorbed antispasmodic, which has shown clear efficacy compared to placebo, in controlling symptoms related to IBS. Otilonium bromide was effective also in comparison to other drugs, such as pinaverium bromide and mebeverine, with a favorable tolerability profile. Further studies are necessary to better define duration of treatment and maximum therapeutic dose.

  11. 苯扎溴铵酊处方改进及苯扎溴铵的含量测定%Improvement of prescription on Benzalkonium Bromide Tincture and de-termination of benzalkonium bromide

    Institute of Scientific and Technical Information of China (English)

    吴海伟; 王晓青; 刘皈阳; 马建丽

    2015-01-01

    Objective To improve prescription of Benzalkonium Bromide Tincture and establish a titration method in determination for content of benzalkonium bromide in Benzalkonium Bromide Alcoholic Solution (eosin was removed from Benzalkonium Bromide Tincture). Methods The content of benzalkonium bromide was detected by setting up capacity analysis method, and found eosin can affect the result of content determination at different degree, therefore eosin com-position was removed from the prescription. The content of benzalkonium bromide in Benzalkonium Bromide Alcoholic Solution was detected by titration method with tetraphenylboron sodium volumetric solution (0.02 mol/L). Results Ben-zalkonium Bromide Tincture changed to Benzalkonium Bromide Alcohol Solution, in content determination, the change of titration end point was obvious and easy to judge. Within the range from 0.4 mg/mL to 1.4 mg/mL, benzalkonium bromide presented a good linear relationship with the consumption volume of tetraphenylboron sodium volumetric solu-tion (r=0.9995), and the equation of linear regression was V=18.3C-0.32. The average recovery of benzalkonium bro-mide in low, middle and high dose was 99.12%, and RSD was 0.84%. Conclusion The method is simple, fast and ac-curate, it can be used for the quality control of Benzalkonium Bromide Alcoholic Solution.%目的:改进苯扎溴铵酊处方,并建立容量分析法测定苯扎溴铵醇溶液(苯扎溴铵酊去除曙红成分)中苯扎溴铵的含量。方法在建立容量分析法测定苯扎溴铵的含量时,发现曙红在不同程度上均能影响含量测定结果,故将曙红成分从处方中删去。采用四苯硼钠(0.02 mol/L)为滴定液,滴定苯扎溴铵醇溶液中苯扎溴铵的含量。结果苯扎溴铵酊制剂更改为苯扎溴铵醇溶液,在含量测定中,滴定终点变化明显,易于判断。苯扎溴铵在浓度0.4~1.4 mg/mL的范围内与消耗四苯硼钠滴定液体积呈良好线性关系,r=0

  12. Illness associated with exposure to methyl bromide-fumigated produce--California, 2010.

    Science.gov (United States)

    2011-07-15

    Methyl bromide (MeBr) is a toxic gas used to fumigate agricultural fields and some produce. The U.S. Department of Agriculture (USDA) requires MeBr fumigation of grapes imported from Chile to prevent invasion by the Chilean false red mite, Brevipalpus chilensis. In 2010, two workers were exposed intermittently to MeBr over several months as part of their job inspecting produce at a cold-storage facility in Carson, California. Both workers had disabling neurologic symptoms (e.g., ataxia, memory difficulties, and dizziness) and elevated serum bromide concentrations. An environmental investigation revealed the potential for MeBr to accumulate in enclosed areas during the transportation and storage of fumigated grapes. Some MeBr air concentrations measured at a single point in time exceeded current 8-hour exposure limits, suggesting that exposure in confined areas could result in poisoning. Possible measures for facilities managers to consider to reduce postfumigation MeBr exposures include 1) increased aeration time, 2) reduction of packaging that might absorb MeBr or limit aeration, and 3) changes in the stacking of pallets to improve air flow. Facilities should monitor air MeBr levels if they store MeBr-fumigated commodities in enclosed spaces entered by workers. Clinicians should consider occupational and environmental exposures in their differential diagnosis, and workers who might become exposed to fumigants should be informed of the health hazards related to these pesticides.

  13. Pressure-Induced Structural and Optical Properties of Organometal Halide Perovskite-Based Formamidinium Lead Bromide.

    Science.gov (United States)

    Wang, Lingrui; Wang, Kai; Zou, Bo

    2016-07-07

    Organometal halide perovskites (OMHPs) are attracting an ever-growing scientific interest as photovoltaic materials with moderate cost and compelling properties. In this Letter, pressure-induced optical and structural changes of OMHP-based formamidinium lead bromide (FAPbBr3) were systematically investigated. We studied the pressure dependence of optical absorption and photoluminescence, both of which showed piezochromism. Synchrotron X-ray diffraction indicated that FAPbBr3 underwent two phase transitions and subsequent amorphization, leading directly to the bandgap evolution with redshift followed by blueshift during compression. Raman experiments illustrated the high pressure behavior of organic cation and the surrounding inorganic octahedra. Additionally, the effect of cation size and the different intermolecular interactions between organic cation and inorganic octahedra result in the fact that FAPbBr3 is less compressible than the reported methylammonium lead bromide (MAPbBr3). High pressure studies of the structural evolution and optical properties of OMHPs provide important clues in optimizing photovoltaic performance and help to design novel OMHPs with higher stimuli-resistant ability.

  14. Self-assembling systems based on amphiphilic alkyltriphenylphosphonium bromides: elucidation of the role of head group.

    Science.gov (United States)

    Gainanova, Gulnara A; Vagapova, Guzalia I; Syakaev, Victor V; Ibragimova, Alsu R; Valeeva, Farida G; Tudriy, Elena V; Galkina, Irina V; Kataeva, Olga N; Zakharova, Lucia Ya; Latypov, Shamil K; Konovalov, Alexander I

    2012-02-01

    A systematic study of the aggregation behavior of alkyltriphenylphosphonium bromides (TPPB-n; n=8, 10, 12, 14, 16, 18; here n is the number of carbon atoms in alkyl groups) in aqueous solutions has been carried out and compared with trimethyl ammonium bromides (TMAB-n). Critical micelle concentrations (cmcs) of TPPB-n and TMAB-n decrease with the number of carbon atoms with the slope parameter of ca.0.3. The low cmcs and effective solubilization power toward Orange OT indicate high micellization capacity of phosphonium surfactants. The low counterion binding parameter β is revealed for TPPB-10 and TPPB-12, while high counterion binding of ≥80% is observed for high TPPB-n homologs. Values of the surface potential ψ calculated on the basis of pK(a) shifts of p-nitrophenols is similar for both series and monotonously increase with alkyl chain length. Several points indicate non-monotonic changes within TPPB-n series. There are peculiarities of the tensiometry and solubilization plots for high homologs and above mentioned increases in counterion binding on transiting from low to high molecular weight surfactants. Differences in aggregation behavior between TPPB and TMAB series and between low and high homologs can be due to the specific structural character of the TPP(+) cation, which is supported by X-ray data. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Recent trends in atmospheric methyl bromide: analysis of post-Montreal Protocol variability

    Directory of Open Access Journals (Sweden)

    S. A. Yvon-Lewis

    2009-08-01

    Full Text Available The atmospheric methyl bromide (CH3Br burden has declined in recent years, in response to the phaseout of agricultural and structural fumigation consumption under the amendments to the Montreal Protocol. The timing and magnitude of this decrease represents an opportunity to examine our current understanding of atmospheric CH3Br and its budget, response to the phaseout, and response to interannual variability in biomass burning and global OH. In this study, simulations obtained from a time-dependent global model of atmospheric CH3Br emissions and uptake are compared to observations from the NOAA flask network. The model includes a detailed gridded ocean model coupled to a time-dependant atmospheric 2-box model. The phaseout of CH3Br production for agricultural uses began in 1998, concurrent with the pulse in biomass burning associated with the 1998 El Niño. The combined effects of three factors (biomass burning, global OH, and anthropogenic phaseout appear to explain most of the observed atmospheric methyl bromide variability over the 1997–2008 period. The global budget remains imbalanced, with a large missing source indicated. The missing source does not exhibit a systematic decline during the phaseout period, and therefore, is not the result of significantly underestimating non-QPS agricultural CH3Br emissions. The model results suggest that the oceans should be less undersaturated than before the phaseout began.

  16. Chemical alternatives to methyl bromide for the control of root-knot nematodes in greenhouses.

    Science.gov (United States)

    Giannakou, Ioannis O; Sidiropoulos, Artemios; Prophetou-Athanasiadou, Demetra

    2002-03-01

    The complete phase-out of methyl bromide from use in developed countries by 1 January 2005 will cause many problems in agricultural industries that are now heavily reliant on its use. Three field experiments were established to compare management tactics on tomato and cucumber in commercial greenhouses naturally infested with root-knot nematodes (Meloidogyne spp). Reduction of nematode juveniles in soil and roots to nil detection levels was observed in all plots following soil fumigation with methyl bromide. A significant reduction of nematode juveniles and root-galling index was observed in plots treated with metham-sodium, dazomet and 1,3-dichloropropene compared with the control and plots treated with non-fumigant nematicides. Reduction of the nematode population led to an increase in fruit yield. However, data collected from the second cultivation season indicated that single control methods such as fumigant or contact nematicides alone cannot drastically decrease initial nematode population and those nematodes which escape control lead to population increase by the end of the cropping season.

  17. Model prediction uncertainty of bromide and pesticides transport in laboratory column

    Science.gov (United States)

    Dusek, Jaromir; Dohnal, Michal; Snehota, Michal; Sobotkova, Martina; Ray, Chittaranjan; Vogel, Tomas

    2016-04-01

    Knowledge of transport parameters of reactive solutes such as pesticides is a prerequisite for reliable predictions of their fate and transport in soil porous systems. Water flow and transport of bromide tracer and five pesticides (atrazine, imazaquin, sulfometuron methyl, S-metolachlor, and imidacloprid) through an undisturbed soil column of tropical Oxisol were analyzed using a one-dimensional numerical model. Laboratory column leaching experiment with three flow interruptions was conducted. The applied numerical model is based on Richards' equation for solving water flow and the advection-dispersion equation for solving solute transport. A global optimization method was used to evaluate the model's sensitivity to transport parameters and the uncertainty of model predictions. Within the Monte Carlo modeling framework, multiple forward simulations searching through the parametric space, were executed to describe the observed breakthrough curves. All pesticides were found to be relatively mobile. Experimental data indicated significant non-conservative behavior of bromide tracer. All pesticides, with the exception of imidacloprid, were found less persistent. Three of the five pesticides (atrazine, sulfometuron methyl, and S-metolachlor) were better described by the linear kinetic sorption model, while the breakthrough curves of imazaquin and imidacloprid were more appropriately approximated using nonlinear instantaneous sorption. Sensitivity analysis suggested that the model is most sensitive to sorption distribution coefficient. The prediction limits contained most of the measured points of the experimental breakthrough curves, indicating adequate model concept and model structure for the description of transport processes in the soil column under study.

  18. Surface Electronic Structure of Hybrid Organo Lead Bromide Perovskite Single Crystals

    KAUST Repository

    Komesu, Takashi

    2016-08-24

    The electronic structure and band dispersion of methylammonium lead bromide, CH3NH3PbBr3, has been investigated through a combination of angle-resolved photoemission spectroscopy (ARPES) and inverse photoemission spectroscopy (IPES), as well as theoretical modeling based on density functional theory. The experimental band structures are consistent with the density functional calculations. The results demonstrate the presence of a dispersive valence band in MAPbBr3 that peaks at the M point of the surface Brillouin zone. The results also indicate that the surface termination of the CH3NH3PbBr3 is the methylammonium bromide (CH3NH3Br) layer. We find our results support models that predict a heavier hole effective mass in the region of -0.23 to -0.26 me, along the Γ (surface Brillouin center) to M point of the surface Brillouin zone. The surface appears to be n-type as a result of an excess of lead in the surface region. © 2016 American Chemical Society.

  19. Effect of chronic administration of phenobarbital, or bromide, on pharmacokinetics of levetiracetam in dogs with epilepsy.

    Science.gov (United States)

    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 phenobarbital in dogs. Copyright © 2015 by the American College of Veterinary Internal Medicine.

  20. Natural Oxidation of Bromide to Bromine in Evaporated Dead Sea Brines

    Science.gov (United States)

    Gavrieli, Ittai; Golan, Rotem; Lazar, Boaz; Baer, Gidi; Zakon, Yevgeni; Ganor, Jiwchar

    2016-04-01

    Highly evaporated Dead Sea brines are found in isolated sinkholes along the Dead Sea. Many of these brines reach densities of over 1.3 kg/L and pHDead Sea brine that drain into the sinkholes. The low pH and the reddish to brownish hue of these brines were an enigma until recently. Despite the rather high total alkalinity (TA) of the Dead Sea (3.826 mmol/kg) the pH of the Dead Sea brine is known to be slightly acidic with a value of ~6.3. In comparison, seawater with the same alkalinity would have a pH value well above 8.3, meaning that H+ activity is 100 fold lower than that of Dead Sea brine. In the present work we assess the apparent dissociation constant value of boric acid (K`B) for the Dead Sea brine and use it to explain the brine's low pH value. We then show that pH decreases further as the brine evaporates and salinity increases. Finally we explain the reddish hue of the hypersaline brines in the sinkholes as due to the presence of dissolved bromine. The latter is the product of oxidation of dissolved bromide, a process that is enabled by the low pH of the hypersaline brines and their high bromide concentration.

  1. Thermodynamics of micellization of hexadecyltrimethylammonium bromide in propylene glycol-water mixture: A conductivity study

    Directory of Open Access Journals (Sweden)

    Janošević-Ležaić Aleksandra M.

    2014-01-01

    Full Text Available Micellization of hexadecyltrimethylammonium bromide (syn. cetyltrimethylammonium bromide, CTAB in propylene glycol-water (30% v/v binary mixture, as well as the thermodynamic properties of the resulting micelles, were investigated by electrical conductivity measurements. The conductivity data were used to determine both the critical micellar concentration (CMC and the micellar ionization degree (α of CTin the temperature range 298.2-310.2 K. The equilibrium model of micelle formation was applied in order to obtain the thermodynamic parameters (the standard molar Gibbs free energy, ΔGm0, enthalpy, ΔHm0 and entropy, ΔSm0 of the micellization process. The values of DGm0 and DHm0 were found to be negative at all investigated temperatures, while the values of ΔSm0 were positive and became more positive as temperature increased. A linear dependence between ΔSm0 and ΔHm0, i.e. an enthalpy-entropy compensation effect, was observed. [Projekat Ministarstva nauke Republike Srbije, br. 172015

  2. Chemical vapor transport and solid-state exchange synthesis of new copper selenite bromides

    Science.gov (United States)

    Charkin, Dmitri O.; Kayukov, Roman A.; Zagidullin, Karim A.; Siidra, Oleg I.

    2017-02-01

    A new dimorphic copper selenite bromide, Cu5(SeO3)4Br2 was obtained via chemical transport reactions. α-Cu5(SeO3)4Br2, monoclinic (1m) and β-Cu5(SeO3)4Br2, triclinic (1a) polymorphs were produced simultaneously upon reaction of amorphous, partially dehydrated copper selenite and copper bromide. 1m is similar to Cu5(SeO3)4Cl2, whereas 1a is distantly related to Ni5(SeO3)4Br2 and Co5(SeO3)4Br2. Attempts to reproduce synthesis of 1a via exchange reaction between Na2SeO3 and CuBr2 resulted in a new Na2[Cu7O2](SeO3)4Br4 (2). Current study demonstrates for the first time, that both chemical vapor and exchange reactions can be employed in preparation of new selenite halides.

  3. Preparation and evaluation of a novel hybrid monolithic column based on pentafluorobenzyl imidazolium bromide ionic liquid.

    Science.gov (United States)

    Shan, Yuanhong; Qiao, Lizhen; Shi, Xianzhe; Xu, Guowang

    2015-01-02

    To develop a novel hybrid monolithic column based on pentafluorobenzyl imidazolium bromide ionic liquid, a new ionic liquid monomer was synthesized from 1-vinylimidazole and pentafluorobenzyl bromide. By employing a facile one-step copolymerization of polyhedral-oligomeric-silsesquioxane-type (POSS) cross-linking agent and the home-made ionic liquid monomer, the hybrid monolithic columns were in situ fabricated in fused-silica capillary. The morphology of monolithic column was characterized by scanning electron microscope (SEM) and the chemical composition was confirmed by Fourier-transform infrared spectroscopy (FT-IR) and elemental analysis. Excellent mechanical stability and slight swelling propensity were exhibited which was ascribed to the rigid hybrid monolithic skeleton. Reproducibility results of run-to-run, column-to-column, batch-to-batch and day-to-day were investigated and the RSDs were less than 0.46%, 1.84%, 3.96% and 3.17%, respectively. The mixed-mode retention mechanism with hydrophobic interaction, π-π stacking, ion-exchange, electrostatic interaction and dipole-dipole interaction was explored systematically using analytes with different structure types. Satisfied separation capability and column efficiency were achieved for the analysis of small molecular compounds such as alkylbenzenes, polycyclic aromatic hydrocarbons, nucleosides and halogenated compounds. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. [Comparative effects of terbutaline sulphate and ipratropium bromide on the respiratory system (author's transl)].

    Science.gov (United States)

    Villate Navarro, J I; Sobradillo Peña, V; Atxotequi Iaraoligoitia, V; Salaverri Nalda, A; Orive Martínez, C

    1980-04-10

    Bronchodilator action of two pharmacologically different drugs have been compared. Ipratropium bromide (Sch 1000) is a synthetic atropine derivative and terbutaline sulphate is a beta-stimulating agent. Twelve asthmatic patients and eight patients with chronic bronquitis received terbutaline 0.50 mg. and ipratropium 0.04 mg by aerosol inhalation. Both drugs were given at random on a consecutive-day schedule. All patients were clinically stable before treatment (basal FEV/VC less than 60 percent). Total lung capacity (TLC) forced expiratory volume (FEV), SRaw, and V'/V curves before and at 15, 60, 120, and 240 minutes after the produce administration were registered. Presence of side-effects was also checked. An intensive bronchodilator action was observed either after inhalation of ipratropium bromide or terbutaline, but statistical studies showed no significant differences between both drugs in relation to intensity and duration of their actions. Sch 1000 caused similar bronchodilator effects in all cases; a more intense effect in patients with chronic bronchitis could not be noticed. Evaluation of V'/V curve, and especially its relation to a same pulmonary volume, pointed out that both drugs act upon small respiratory airways. Advance side-effects were not present.

  5. Interaction of removal Ethidium Bromide with Carbon Nanotube: Equilibrium and Isotherm studies.

    Science.gov (United States)

    Moradi, Omid; Norouzi, Mehdi; Fakhri, Ali; Naddafi, Kazem

    2014-01-08

    Drinking water resources may be contaminated with Ethidium Bromide (EtBr) which is commonly used in molecular biology laboratories for DNA identification in electrophoresis. Carbon nanotubes are expected to play an important role in sensing, pollution treatment and separation techniques. In this study adsorption of Ethidium Bromide on single-walled carbon nanotubes (SWCNTs) and carboxylate group functionalized single-walled carbon nanotube (SWCNT-COOH) surfaces have been investigated by UV-vis spectrophotometer. The effect of contact time, initial concentration and temperature were investigated. The adsorbents exhibits high efficiency for EtBr adsorption and equilibrium can be achieved in 6 and 3 min for SWCNTs and SWCNT-COOH, respectively. The effect of temperature on adsorption of EtBr by toward adsorbents shows the process in this research has been endothermic. The results showed that the equilibrium data were well described by the Langmuir isotherm model, with a maximum adsorption capacity of 0.770 and 0.830 mg/g for SWCNTs and SWCNT-COOH, respectively. The adsorption of EtBr on SWCNT-COOH is more than SWCNTs surfaces. A comparison of kinetic models was evaluated for the pseudo first-order, pseudo second-order models. Pseudo second-order was found to agree well with the experimental data.

  6. Moving away from methyl bromide: political economy of pesticide transition for California strawberries since 2004.

    Science.gov (United States)

    Mayfield, Erin N; Norman, Catherine Shelley

    2012-09-15

    We examine the progress of the phaseout of the use of the pesticide methyl bromide in the production of California field strawberries. This phaseout is required under the Montreal Protocol and has been contentious in this sector, which receives exemptions from the schedule initially agreed under the treaty, and in international negotiations over the future of the Protocol. We examine the various ex-ante predictions of the impacts on growers, consumers and trade patterns in light of several years of declining allocations under the Critical Use provisions of the Protocol and the 2010 approval of iodomethane for use in California and subsequent 2012 withdrawal of this alternative from the US market. We find that, contrary to ex-ante industry claims, the years of declining methyl bromide use have been years of rising yields, acreage, exports, revenues and market share for California growers, even when faced with a global recession and increased imports from Mexican growers who retain the right to use the chemical under the Protocol. This has implications for the Protocol as a whole and for the remainder of the US phaseout of this chemical in particular. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Bromide as a tracer for studying water movement and nitrate displacement in soils: comparison with stable isotope tracers; Bromid als Tracer zur Untersuchung der Wasserbewegung und der Nitratverlagerung in Boeden: Vergleich mit stabilisotopen Tracern

    Energy Technology Data Exchange (ETDEWEB)

    Russow, R.; Knappe, S. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Bad Lauchstaedt (Germany). Sektion Bodenforschung

    1999-02-01

    Tracers are an ideal means of studying water movement and associated nitrate displacement. Often bromide is preferred as a tracer because it is considered a representative tracer for water and because, being a conservative tracer (i.e. not involved in chemical and biological soil processes), it can be used for studying anion transport in soils. Moreover, it is less expensive and easier to measure than the stable isotopes deuterium and {sup 15}N. Its great advantage over radioactive tracers (e.g. tritium), which outweighs their extreme sensitivity and ease of measurement and which it has in common with stable isotopes, is that it does not require radiation protection measures. However, there are also constraints on the use of bromide as a tracer in soil/water/plant systems. Our own studies on different soils using D{sub 2}O, bromide and [{sup 15}N]-nitrate in lysimeters suggest that the above assumptions on bromide tracers need not always be valid under conditions as they prevail in biologically active soils. As the present paper shows, these studies permit a good assessment of the possibilities and limits to these tracers. [Deutsch] Fuer die Untersuchung der Wasserbewegung sowie der daran gekoppelten Nitrat-Verlagerung ist der Einsatz von Tracern das Mittel der Wahl. Dabei wird Bromid als Tracer haeufig bevorzugt, da es allgemein als ein repraesentativer Tracer fuer Wasser und als konservativer Tracer (nicht involviert in chemische und biologische Bodenprozesse) zur Untersuchung des Anionentransportes in Boeden angesehen wird und es gegenueber den stabilen Isotopen Deuterium und {sup 15}N billiger und einfacher zu bestimmen ist. Gegenueber den radioaktiven Tracern (z.B. Tritium), die zwar sehr empfindlich und einfach messbar sind, besteht der grosse Vorteil, dass, wie bei den stabilen Isotopen, keine Strahlenschutzmassnahmen ergriffen werden muessen. Es gibt jedoch auch einschraenkende Hinweise fuer die Verwendung von Bromid als Tracer im System Boden

  8. The Research on Programmable Control System of Lithium-Bromide Absorption Refrigerating Air Conditioner Based on the Network

    Directory of Open Access Journals (Sweden)

    Sun Lunan

    2016-01-01

    Full Text Available This article regard the solar lithium-bromide absorption refrigerating air conditioning system as the research object, and it was conducting adequate research of the working principle of lithium bromide absorption refrigerating machine, also it was analyzing the requirements of control system about solar energy air conditioning. Then the solar energy air conditioning control system was designed based on PLC, this system was given priority to field bus control system, and the remote monitoring is complementary, which was combining the network remote monitoring technology. So that it realized the automatic control and intelligent control of new lithium bromide absorption refrigerating air conditioning system with solar energy, also, it ensured the control system can automatically detect and adjust when the external conditions was random changing, to make air conditioning work effectively and steadily, ultimately ,it has great research significance to research the air conditioning control system with solar energy.

  9. Combination of ozonation and photocatalysis for purification of aqueous effluents containing formic acid as probe pollutant and bromide ion.

    Science.gov (United States)

    Parrino, F; Camera-Roda, G; Loddo, V; Palmisano, G; Augugliaro, V

    2014-03-01

    The treatment by advanced oxidation processes (AOPs) of waters contaminated by organic pollutants and containing also innocuous bromide ions may generate bromate ions as a co-product. In the present work heterogeneous photocatalysis and ozonation have individually been applied and in combination (integrated process) to degrade the organic compounds in water containing also bromide anions. The results show that: i) the sole photocatalysis does not produce bromate ions and in the case of its presence, it is able to reduce bromate to innocuous bromide ions; ii) the integration of photocatalysis and ozonation synergistically enhances the oxidation capabilities; and iii) in the integrated process bromate ions are not produced as long as some oxidizable organics are present.

  10. Rapid, microscale, acetyl bromide-based method for high-throughput determination of lignin content in Arabidopsis thaliana.

    Science.gov (United States)

    Chang, Xue Feng; Chandra, Richard; Berleth, Thomas; Beatson, Rodger P

    2008-08-27

    The acetyl bromide method has been modified to enable the rapid microscale determination of lignin content in Arabidopsis with the goal of determining the genes that control lignin in plants. Modifications include reduction in sample size, use of a microball mill, adoption of a modified rapid method of extraction, use of an ice-bath to stabilize solutions and reduction in the volume of solutions. The microscale method was shown to be rapid, accurate and precise with values in agreement with those determined by the full-scale acetyl bromide method. The extinction coefficient for Arabidopsis lignin, dissolved using acetyl bromide, was determined to be 23.35 g(-1) L cm(-1) at 280 nm. This value is independent of the Arabidopsis accession, environmental growth conditions and is insensitive to lignin structure. The newly developed method can be used to determine lignin content in the inflorescence stems of Arabidopsis for mapping of lignin-related genes.

  11. Off-site air monitoring following methyl bromide chamber and building fumigations and evaluation of the ISCST air dispersion model

    Energy Technology Data Exchange (ETDEWEB)

    Barry, T.; Swgawa, R.; Wofford, P. [Cal EPA, Sacramento, CA (United States)] [and others

    1995-12-31

    The Department of Pesticide Regulation`s preliminary risk characterization of methyl bromide indicated an inadequate margin of safety for several exposure scenarios. Characterization of the air concentrations associated with common methyl bromide use patterns was necessary to determine specific scenarios that result in an unacceptable margin of safety. Field monitoring data were used in conjunction with the Industrial Source Complex, Short Tenn (ISCST) air dispersion model to characterize air concentrations associated with various types of methyl bromide applications. Chamber and building fumigations were monitored and modelled. For each fumigation the emission rates, chamber or building specifications and on-site meteorological data were input into the ISCST model. The model predicted concentrations were compared to measured air concentrations. The concentrations predicted by the ISCST model reflect both the pattern and magnitude of the measured concentrations. Required buffer zones were calculated using the ISCST output.

  12. [Effects of bromide and ferric ions on formation of tri-halomethanes during disinfection of drinking water by chlorine].

    Science.gov (United States)

    Zhu, Zhi-Liang; Wang, Jing; Ge, Yuan-Xin; Ma, Hong-Mei; Zhao, Jian-Fu

    2007-06-01

    Effects of bromide and ferric ions on the formation and distribution of tri-halomethanes (THMs) have been investigated. As disinfection by-product (DBP) model precursors of natural water, humic acid solutions were used and a series of experiments were conducted. The results showed that bromide in this reaction system not only contributed to the increase of brominated species, but also the total tri-halomethanes. When the concentration of Br(-) was 1.0 mg/L, the total amount of produced THMs reached to 270% of that without bromide ions. In the presence of bromide, ferric ions decreased the production of THMs at pH 6, but increased the production of THMs at pH 8, especially for the amount of tri-bromomethanes. When the concentration of Fe3+ was 5 mg/L, the amount of produced tri-bromomethanes had an increment of 54% (from 51.7 microg/L to 79.4 microg/L), and the total amount of THMs increased from 113.49 microg/L to 162.09 microg/L. Bromide ions had a significant effect on carcinogenicity risk in disinfection of drinking water by chlorine, and the co-existence of ferric ion and bromide in alkalescent environment can result in the biggest challenge on carcinogenicity risk. Under the condition of 0.2 mg/L Br(-), 5 mg/L Fe3+ and pH 6, the carcinogenicity risk increased 2.5 times than that without Br(-) and Fe3+, and much higher increment of 5.1 times appeared when pH was 8.

  13. Extended analysis of a double-blind, placebo-controlled, 15-week study with otilonium bromide in irritable bowel syndrome.

    Science.gov (United States)

    Glende, Manfred; Morselli-Labate, Antonio M; Battaglia, Giuseppe; Evangelista, Stefano

    2002-12-01

    In order to follow the most recent developments and recommendations in trial methodology for drug evaluation in patients with irritable bowel syndrome, we performed an extended analysis of a large clinical trial from a previously published study of otilonium bromide, using an assessment that integrates the key symptoms of irritable bowel syndrome. A large-scale clinical trial with a double-blind, placebo-controlled, parallel-group study design was conducted in 378 patients, treated for 15 weeks with the recommended standard dose of 40 mg otilonium bromide or placebo three times daily. The study was based on the collection of 12 single efficacy endpoints. The new efficacy assessment was based on the data reported by the patients. Rather than demonstrating score differences between the treatment groups of the study, we carried out an assessment that integrates the most frequent symptoms reported (pain frequency and intensity, presence of meteorism and distension) by the patient. The rate of response to treatment within 2-4 months (the primary efficacy outcome measure) was significantly higher in the otilonium bromide group (36.9%) than in the placebo group (22.5%; P = 0.007). In each month of treatment, the rate of monthly response was higher in the otilonium bromide group as compared to the placebo group (P otilonium bromide than in the placebo-treated group, with differences ranging from 10% to 20%. The subgroup analysis of the intestinal habits endpoint indicates that patients with diarrhoea have an additional benefit. The present re-evaluation of a previously published study confirms that otilonium bromide is more effective than placebo for the treatment of irritable bowel syndrome, being very efficient in relieving pain and discomfort.

  14. Investigation of thermodynamic parameters of cetyl pyridinium bromide sorption onto ZSM-5 and natural clinoptilolite[Thermodynamic properties; Sorption; Cetyl pyridinium bromide; ZSM-5 and natural clinoptilolite

    Energy Technology Data Exchange (ETDEWEB)

    Ghiaci, M. E-mail: mghiaci@cc.iut.ac.ir; Kia, R.; Kalbasi, R.J

    2004-02-01

    A study was undertaken to determine the influence of temperature and surfactant concentration on the adsorption of cetyl pyridinium bromide on two ZSM-5 zeolites, and on natural clinoptilolite. The effect of temperature on adsorption and thermodynamic properties was investigated by making measurements at (297, 303, 307, 313) K. The results show that the calculated curves from the general isotherm equation can represent the experimental data very well up to T=313 K. Based on the calculation of the thermodynamics of adsorption, it is evident that the principle contribution to the {delta}G{sup compfn}{sub hm} of negative value is the large positive value of {delta}S{sup compfn}{sub hm} (36 to 52 J {center_dot} mol{sup -1}), whereas {delta}H{sup compfn}{sub hm} is positive and in the range of 1 to 7 kJ {center_dot} mol{sup -1}. Therefore, similar to the micellisation in bulk solution, the second step of surfactant adsorption is an entropy-driven process.

  15. Protective effect of testosterone on cognitive deficits induced by ethidium bromide in experimental model of multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Sallahadin Feizollah

    2015-11-01

    Full Text Available Background: Multiple Sclerosis (MS is a neurodegenerative disease of the central nervous system (CNS. The hippocampus is a vital center for learning and memory; it is extremely vulnerable to neurodegenerative diseases. The male hormones could be neuroprotective for the CNS. The current study is an attempt to investigate the effect of testosterone on learning and spatial memory following the demyelination of CA1 area by the injection of ethidium bromide in the rats' hippocampus. Methods: This experimental study has been conducted on healthy rats in the faculty of science of the Urmia University from September 2013 to February 2015. For demyelination in all previously gonadectomized healthy rats, 3µl ethidium bromide was injected into the CA1 area of rats by stereotaxic surgery. In addition, the treatment groups received 1µl testosterone (6µg/µl during a 20-day timeframe on a daily basis after demyelination by the ethidium bromide. The control groups had no drug injection. The process of the learning and spatial memory of the rats were closely monitored by the radial Maze. The demyelination and remyelination in the hippocampus were checked by the myelin-specific coloring (Luxol fast blue and Cresyl violet. Results: The histological results suggest that the testosterone is capable of minimizing the destructive impacts of ethidium bromide in the treatment group as well as enhancing the remyelination process. In the group treated by testosterone, the percentage of the pyknotic cells 20 days after demyelination induction, represented a significant reduction compared to that of ethidium bromide group (P=0.008. The behavioral studies analyses show that the amount of the food finding time in those groups received ethidium bromide was significantly longer than those of the control groups (P=0.001. Furthermore, the application of the testosterone in the treatment groups reduced the extent of demyelination while the memory impairment induced by the

  16. Copper/N,N-Dimethylglycine Catalyzed Goldberg Reactions Between Aryl Bromides and Amides, Aryl Iodides and Secondary Acyclic Amides

    Directory of Open Access Journals (Sweden)

    Liqin Jiang

    2014-08-01

    Full Text Available An efficient and general copper-catalyzed Goldberg reaction at 90–110 °C between aryl bromides and amides providing the desired products in good to excellent yields has been developed using N,N-dimethylglycine as the ligand. The reaction is tolerant toward a wide range of amides and a variety of functional group substituted aryl bromides. In addition, hindered, unreactive aromatic and aliphatic secondary acyclic amides, known to be poor nucleophiles, are efficiently coupled with aryl iodides through this simple and cheap copper/N,N-dimethylglycine catalytic system.

  17. Palladium-Catalyzed Carbonylation Reactions of Aryl Bromides at Atmospheric Pressure: A General System Based on Xantphos

    OpenAIRE

    Martinelli, Joseph R.; Watson, Donald A.; Freckmann, Dominique M. M.; Barder, Timothy E.; Buchwald, Stephen L.

    2008-01-01

    A method for the Pd-catalyzed carbonylation of aryl bromides has been developed using Xantphos as the ligand. This method is effective for the direct synthesis of Weinreb amides, 1° and 2° benzamides and methyl esters from the corresponding aryl bromides at atmospheric pressure. In addition, a putative catalytic intermediate, (Xanphos)Pd(Br)benzoyl, was prepared and an X-ray crystal structure was obtained revealing an unusual cis-coordination mode of Xantphos in this palladium-acyl complex.

  18. Characterization of the corrosion products formed on mild steel in acidic medium with N-octadecylpyridinium bromide as corrosion inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Nava, N., E-mail: tnava@imp.mx; Likhanova, N. V. [Direccion de Investigacion y Posgrado, Instituto Mexicano del Petroleo (Mexico); Olivares-Xometl, O. [Benemerita Universidad Autonoma de Puebla, Facultad de Ingenieria Quimica (Mexico); Flores, E. A. [Direccion de Investigacion y Posgrado, Instituto Mexicano del Petroleo (Mexico); Lijanova, I. V. [CIITEC, Instituto Politecnico Nacional (Mexico)

    2011-11-15

    The characterization of the corrosion products formed on mild steel SAE 1018 after 2 months exposure in aqueous sulfuric acid with and without corrosion inhibitor N-octadecylpyridinium bromide has been carried out by means of transmission {sup 57}Fe Moessbauer spectroscopy and X-ray powder diffraction (XRD). The major constituent of the rust formed in this environment without corrosion inhibitor is goethite ({alpha}-FeOOH). The samples with N-octadecylpyridinium bromide contain rozenite and large amounts of melanterite in the corrosion layers.

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

    Science.gov (United States)

    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

  20. Effect of ethidium bromide on transmission of mitochondrial genomes and DNA synthesis in the petite negative yeast Schizosaccharomyces pomhe.

    Science.gov (United States)

    Wolf, K; Del Giudice, L

    1980-04-01

    Treatment of haploid strains of the petite negative yeast Schizosaccharomyces pomhe with ethidium bromide prior to mating with untreated cells reduces transmission of mitochondrial markers from the treated strains. This effect is fully reversible after 20 generations of growth in drug free medium before mating. In contrast to the petite positive yeast Saccharomyces cerevisiae, where nuclear DNA synthesis is not affected but mitochondrial DNA is degraded in the presence of 20 μg/ml ethidium bromide, the same concentration decreases both nuclear and mitochondrial DNA synthesis in Schizosaccharomyces pomhe. After removal of the drug, nuclear DNA synthesis increases faster than its mitochondrial counterpart in Schizosaccharomyces pomhe.

  1. An innovative experimental design reveals the spatial correlation between landuse, irrigation properties, and bromide leaching

    Science.gov (United States)

    Schwen, A.; Yang, Y.; Walton, J.; Wendroth, O.

    2012-04-01

    Understanding the relationship between leaching of pesticides and soil hydraulic properties under different land use conditions is critical to our understanding of the flow of water and solutes in soils and efforts to model these flow characteristics. One problem inherent in the measurement of solute leaching in field experiments is the considerable high natural spatial variability of flow-controlling soil properties. Thus, analyzing treatment effects based on the mean and the variance of observations can become obsolete if there is a huge inherent variance in the set of measurements. Moreover, no spatial range of influence can be derived from the observations. To overcome this limitation, the spatial covariance and cross-variance between measurements was used as decision and quality criteria in the present study. This study aims to demonstrate that focussing on the spatial covariance of observations and considering their spatial process can provide a measure of spatial representativity or scale-specific variance. We introduce a novel experimental scheme, where the treatments are arranged in a scale-dependent manner. In a field trial in Lexington, Kentucky, bromide leaching under two contrasting land use systems (no-till agricultural crops vs. pasture) was compared. After surface application of tracer solution (KBr), the experimental field was irrigated using different time-delays (1, 4 and 24 hours) as well as two different irrigation amounts and two different intensities. At the end, the KBr-concentration in the soil profile was determined using auger samplings. The data was correlated with the applied boundary conditions by spatial statistical methods such as semivariograms, cross-semivariograms and spectral analysis. Our results show distinct differences in the leaching behaviour between the two analyzed land uses with an deeper infiltration in the no-till agricultural field. This can be partly related to a higher initial soil water content in this treatment

  2. Nanosized sustained-release pyridostigmine bromide microcapsules: process optimization and evaluation of characteristics

    Directory of Open Access Journals (Sweden)

    Tan Q

    2013-02-01

    Full Text Available Qunyou Tan,1,* Rong Jiang,3,* Meiling Xu,2,4,* Guodong Liu,5,* Songlin Li,1 Jingqing Zhang21Department of Thoracic Surgery, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 2Medicine Engineering Research Center, Chongqing Medical University, 3Stem Cells and Tissue Engineering Research, Chongqing Medical University, 4Department of Pharmacy, Chongqing Emergency Medical Center, 5Eighth Department, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, People’s Republic of China*These authors contributed equally to this workBackground: Pyridostigmine bromide (3-[[(dimethylamino-carbonyl]oxy]-1-methylpyridinium bromide, a reversible inhibitor of cholinesterase, is given orally in tablet form, and a treatment schedule of multiple daily doses is recommended for adult patients. Nanotechnology was used in this study to develop an alternative sustained-release delivery system for pyridostigmine, a synthetic drug with high solubility and poor oral bioavailability, hence a Class III drug according to the Biopharmaceutics Classification System. Novel nanosized pyridostigmine-poly(lactic acid microcapsules (PPNMCs were expected to have a longer duration of action than free pyridostigmine and previously reported sustained-release formulations of pyridostigmine.Methods: The PPNMCs were prepared using a double emulsion-solvent evaporation method to achieve sustained-release characteristics for pyridostigmine. The preparation process for the PPNMCs was optimized by single-factor experiments. The size distribution, zeta potential, and sustained-release behavior were evaluated in different types of release medium.Results: The optimal volume ratio of inner phase to external phase, poly(lactic acid concentration, polyvinyl alcohol concentration, and amount of pyridostigmine were 1:10, 6%, 3% and 40 mg, respectively. The negatively charged PPNMCs had an average particle size of 937.9 nm

  3. COPD patient satisfaction with ipratropium bromide/albuterol delivered via Respimat: a randomized, controlled study

    Directory of Open Access Journals (Sweden)

    Ferguson GT

    2013-03-01

    Full Text Available Gary T Ferguson,1 Mo Ghafouri,2 Luyan Dai,2 Leonard J Dunn31Pulmonary Research Institute of Southeast Michigan, Livonia, MI, USA; 2Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA; 3Clinical Research of West Florida, Inc, Clearwater, FL, USABackground: Ipratropium bromide/albuterol Respimat inhaler (CVT-R was developed as an environmentally friendly alternative to ipratropium bromide/albuterol metered-dose inhaler (CVT-MDI, which uses a chlorofluorocarbon propellant.Objective: The objective of this study was to evaluate patient satisfaction, device usage, and long-term safety of CVT-R compared to CVT-MDI, and to the simultaneous administration of ipratropium bromide hydrofluoroalkane (HFA; I and albuterol HFA (A metered-dose inhalers as dual monotherapies (I + A.Design: This is a 48-week, open-label, randomized, active-controlled, parallel-group study (n = 470 comparing CVT-R to CVT-MDI and to I + A.Participants: Patients were at least 40 years of age, diagnosed with chronic obstructive pulmonary disease (COPD, and current or exsmokers.Interventions: Patients were randomized to receive: (1 CVT-R, one inhalation four times daily (QID; or (2 CVT-MDI, two inhalations QID; or (3 I + A two inhalations of each inhaler QID.Main measures: Patient Satisfaction and Preference Questionnaire (PASAPQ performance score (primary endpoint and adverse events.Key results: PASAPQ performance score was significantly higher (CVT-R versus CVT-MDI, 9.6; and CVT-R versus I + A, 6.2; both P < 0.001 when using CVT-R compared to CVT-MDI or I + A at all visits starting from week 3, while CVT-MDI and I + A treatment groups were similar. Time to first COPD exacerbation was slightly longer in the CVT-R group compared to the other treatment groups, although it did not reach statistical significance (CVT-R versus CVT-MDI, P = 0.57; CVT-R versus I + A, P = 0.22. Rates of withdrawal and patient refusal to continue treatment were lower in CVT-R compared with CVT

  4. Physicochemical and thermodynamic characterization of N-alkyl-N-methylpyrrolidinium bromides and its aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Zawadzki, Maciej, E-mail: mzawadzki@ch.pw.edu.pl; Królikowska, Marta; Lipiński, Paweł

    2014-08-10

    Highlights: • The aqueous solutions of bromide-based ionic liquids have been studied. • The synthesis and basic thermal characterization of pure IL have been done. • The density, dynamic viscosity, SLE and VLE have been determined. • The experimental data have been correlated using appropriate equations. - Abstract: This work is a continuation of our research of ionic liquids to investigate the physicochemical and thermodynamic properties of (ionic liquid + water) binary mixtures as a novel alternative working pair for the absorption heat pump cycle. In this work, a series of organic salts: N-propyl-N-methyl-pyrrolidinium bromide, [C{sub 1}C{sub 3}PYR]Br; N-butyl-N-methylpyrrolidinium, [C{sub 1}C{sub 4}PYR]Br and N-pentyl-N-methylpyrrolidinium bromide, [C{sub 1}C{sub 5}PYR]Br have been synthesized. The structures of new compounds have been confirmed using NMR spectra and elementary analysis. The basic thermal characterization of pure ILs, including temperature and enthalpy of phase transition (T{sub tr}, Δ{sub tr}H), temperature and enthalpy of melting (T{sub m,} Δ{sub m}H) have been measured using a differential scanning microcalorimetry technique (DSC). Decomposition temperature of the tested ILs were detected by the simultaneous TG/DTA experiments. The effect of temperature on the density (ρ) and dynamic viscosity (η) is reported over a wide temperature range from 298.15 to 343.15 K at ambient pressure. From experimental density data, the excess molar volumes (V{sup E}) were calculated and correlated using Redlich–Kister equation. The isothermal vapour–liquid phase equilibria (VLE) have been measured by an ebulliometric method at wide temperature range from 328.15 to 368.15 K and pressure up to 85 kPa. Experimental data have been correlated by means of NRTL equation. The solid–liquid phase equilibria (SLE) for the tested binary mixtures have been determined over whole composition range using dynamic method. The NRTL equation using parameters

  5. Copper-catalysed N-arylation of arylsulfonamides with aryl bromides and aryl iodides using KF/Al2O3

    Indian Academy of Sciences (India)

    Rahman Hosseinzadeh; Mahmood Tajbakhsh; Maryam Mohadjerani; Mohammad Alikarami

    2010-03-01

    An efficient synthesis of -arylsulfonamides with a variety of aryl bromides, aryl iodides and heteroaryl bromides using KF/Al2O3 as a suitable base, CuI as an inexpensive catalyst and ,'-dimethylethylenediamine (,'-DMEDA) as an effective ligand is described.

  6. Effect of emepronium bromide (Cetiprin) on symptoms and urinary bladder function after transurethral resection of the prostate. A double-blind randomized trial

    DEFF Research Database (Denmark)

    Bonnesen, T; Tikjøb, G; Kamper, A L

    1984-01-01

    75 patients were randomized to be treated with either emepronium bromide (Cetiprin) 200 mg 4 times a day or placebo after transurethral resection of the prostate. The patients were evaluated urodynamically pre- and postoperatively, and further evaluated by micturition symptom charts. No significant...... differences in symptoms or objective findings were found between the patients treated with emepronium bromide and those treated with placebo....

  7. Increased paracellular absorption by bile salts and P-glycoprotein stimulated efflux of otilonium bromide in Caco-2 cells monolayers as a model of intestinal barrier.

    Science.gov (United States)

    Catalioto, Rose-Marie; Triolo, Antonio; Giuliani, Sandro; Altamura, Maria; Evangelista, Stefano; Maggi, Carlo Alberto

    2008-09-01

    The present study investigates the intestinal permeability of otilonium bromide, a spasmolytic drug used to treat irritable bowel syndrome, across Caco-2 cell monolayers. The amount of otilonium bromide transported was determined by high-performance liquid chromatography-mass spectrometry. Epithelial barrier integrity was estimated by measuring transepithelial electrical resistance and the transport of reference compounds, P-glycoprotein activity by measuring rhodamine 123 efflux. Results showed that the apparent permeability of otilonium bromide was comparable to that of our zero permeability marker, inulin, in the apical-to-basal direction and similar to that of rhodamine 123 in the basal-to-apical direction. The P-glycoprotein substrate, verapamil, prevented otilonium bromide efflux and, conversely, otilonium bromide inhibited P-glycoprotein activity. Bile salts induced a transient opening of tight junctions, as measured by selective increase of paracellular transport, and significantly enhanced the absorption of otilonium bromide. In turn otilonium bromide potentiates the effect of bile salts on tight junctions without modifying their critical micellar concentration or altering cell viability. In conclusion, otilonium bromide is a paracellularly transported drug whose absorption, in amounts sufficient to exert a spasmolytic effect, is favoured by bile salts. P-glycoprotein, by stimulating efflux, contributes to remove excess compound, restraining its distribution and site of action to the intestinal wall.

  8. Increase in mitotic recombination in diploid cells of Aspergillus nidulans in response to ethidium bromide

    Directory of Open Access Journals (Sweden)

    Tânia C.A. Becker

    2003-01-01

    Full Text Available Ethidium bromide (EB is an intercalating inhibitor of topoisomerase II and its activities are related to chemotherapeutic drugs used in anti-cancer treatments. EB promotes several genotoxic effects in exposed cells by stabilising the DNA-enzyme complex. The recombinagenic potential of EB was evaluated in our in vivo study by the loss of heterozygosity of nutritional markers in diploid Aspergillus nidulans cells through Homozygotization Index (HI. A DNA repair mutation, uvsZ and a chromosome duplication DP (II-I were introduced in the genome of tested cells to obtain a sensitive system for the recombinagenesis detection. EB-treated diploid cells had HI values significantly greater than the control at both concentrations (4.0 x 10-3 and 5.0 x 10-3 mM. Results indicate that the intercalating agent is potentially capable of inducing mitotic crossing-over in diploid A. nidulans cells.

  9. Interaction between dimethyldioctadecylammonium bromide-modified PLGA microspheres and hyaluronic acid

    Science.gov (United States)

    Mulia, Kamarza; Devi, Krisanti, Elsa

    2017-02-01

    In application of intravitreal injection, an extended drug delivery system is desired so that the frequency of injection to treat diabetic retinopathy may be reduced. Poly(lactic-co-glycolic acid) polymer (PLGA) was used to encapsulate a model drug in the form of microspheres. The zeta potential of dimethyldioctadecylammonium bromide (DDAB)-modified PLGA microspheres in water was proportional to the DDAB concentration used in the preparation step, up to +57.8 mV. The scanning electron microscope pictures and the zeta potential data (SEM) confirmed that the surface of the PLGA has been modified by the cationic surfactant and that electrostatic interaction between the positively charged microspheres and the negatively charged vitreous were present.

  10. [Investigation of the oxidation reaction of O3 with bromide ion in aqueous solution].

    Science.gov (United States)

    Yu, Xiao-Ting; Zhang, Jia-Hui; Pan, Xun-Xi; Zhang, Ren-Xi; Hou, Hui-Qi

    2012-09-01

    The reaction mechanism of O3 with bromide ion in aqueous solution was studied by ion chromatography and UV-Vis spectrometry instruments. Ion chromatography analysis showed that only 10% of Br- which was oxidized by ozone was formed into bromate ion. The results demonstrated that the final products of the oxidation reaction were identified as Br2 and Br3- except for BrO3-. The formation of Br3- which was yielded from the reaction of Br2 with Br- was the major process in the reaction of Br attacked by O3. The characteristic absorption spectrum of Br3- with an absorption peak at 260 nm was also investigated. The results may provide helpful information about the mechanism of the oxidation reaction of Br- with O3 and fate of Br- or its derivatives in the environment by the oxidation processes.

  11. Study of cyclic quaternary ammonium bromides by B3LYP calculations, NMR and FTIR spectroscopies.

    Science.gov (United States)

    Brycki, Bogumił; Szulc, Adrianna; Kowalczyk, Iwona

    2010-08-16

    N,N-dioctyl-azepanium, -piperidinium and -pyrrolidinium bromides 1-3, have been obtained and characterized by FTIR and NMR spectroscopy. DFT calculations have also been carried out. The optimized bond lengths, bond angles and torsion angles calculated by B3LYP/6-31G(d,p) approach have been presented. Both FTIR and Raman spectra of 1-3 are consistent with the calculated structures in the gas phase. The screening constants for 13C and 1H atoms have been calculated by the GIAO/B3LYP/6-31G(d,p) approach and analyzed. Linear correlations between the experimental 1H and 13C chemical shifts and the computed screening constants confirm the optimized geometry.

  12. Behavior of aqueous Tetrabutylammonium bromide - a combined approach of microscopic simulation and neutron scattering

    CERN Document Server

    Bhowmik, Debsindhu

    2016-01-01

    Aqueous solution of tetrabutylammonium bromide is studied by quasi-elastic neutron scattering, to give information on the dynamic modes involving the ions present. Using a careful combination of two techniques, time-of-flight (TOF) and neutron spin echo (NSE), we de- couple the dynamic information in both the coherently and incoherently scattered signal from this system. We take advantage of the different intensity ratio of the two signals, as detected by each of the techniques, to achieve this decoupling. By using heavy water as the sol- vent, the tetrabutylammonium cation is the only hydrogen-containing species in the system and gives rise to a significant incoherent scattered intensity. The dynamic analysis of the incoherent signal (measured by TOF) leads to a translational diffusion coefficient of the cation as that is in good agreement with previous NMR, neutron scattering and tracer diffusion measurements. The dynamic analysis of the coherent signal observed at wave-vectors < 0.6 angstrom^(-1) (measu...

  13. Synthesis of thio-heterocyclic analogues from Baylis-Hillman bromides as potent cyclooxygenase-2 inhibitors.

    Science.gov (United States)

    Santhoshi, Amlipur; Mahendar, Budde; Mattapally, Saidulu; Sadhu, Partha Sarathi; Banerjee, Sanjay Kumar; Jayathirtha Rao, Vaidya

    2014-04-15

    A series of thio-substituted pyrimidine, benzoxazole, benzothiazole and triazole analogues were synthesized from Baylis-Hillman bromides in a clean and efficient way. The synthesized twenty new compounds were subjected to in vitro COX-1 and COX-2 inhibitory activity. Majority of compounds found to be highly selective COX-2 inhibitor. Seven compounds (16e, 16f, 16k, 16l, 16m, 16r and 16s) displayed anti-inflammatory activity at micromolar concentrations with IC50 values for COX-2 inhibition ranging from 2.93 to 5.34 μM compared to reference drug whose IC50 is 2.66 μM. All these seven compounds had very little COX-1 inhibition property and thus are suitable candidates for anti-inflammatory drugs with less gastrointestinal side effect. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Study of Cyclic Quaternary Ammonium Bromides by B3LYP Calculations, NMR and FTIR Spectroscopies

    Directory of Open Access Journals (Sweden)

    Iwona Kowalczyk

    2010-08-01

    Full Text Available N,N-dioctyl-azepanium, -piperidinium and -pyrrolidinium bromides 1-3, have been obtained and characterized by FTIR and NMR spectroscopy. DFT calculations have also been carried out. The optimized bond lengths, bond angles and torsion angles calculated by B3LYP/6-31G(d,p approach have been presented. Both FTIR and Raman spectra of 1-3 are consistent with the calculated structures in the gas phase. The screening constants for 13C and 1H atoms have been calculated by the GIAO/B3LYP/6-31G(d,p approach and analyzed. Linear correlations between the experimental 1H and 13C chemical shifts and the computed screening constants confirm the optimized geometry.

  15. Characterization of potassium bromide crystals grown in the aqueous solution of picric acid

    Energy Technology Data Exchange (ETDEWEB)

    Maheswari, J. Uma, E-mail: umak.anand@gmail.com [Department of Physics, The M.D.T.Hindu College, Tirunelveli 627010, Tamilnadu (India); Krishnan, C. [Department of Physics, Arignar Anna College, Aralvoymoli 629301, Tamilnadu (India); Kalyanaraman, S. [Physics Research Centre, Sri Paramakalyani College, Alwarkurichi 627412, Tamilnadu (India); Selvarajan, P. [Department of Physics, Aditanar College of Arts and Science, Tiruchendur 628216, Tamilnadu (India)

    2016-12-01

    Potassium bromide crystals were grown in the aqueous solution of picric acid by slow evaporation technique at room temperature. X-ray Diffraction (XRD) analysis ensures that the grown sample is in Fm3m space group and FCC structure. Energy Dispersive X-ray Spectroscopy (EDX) reveals the presence of elements in the title compound. UV–Vis-NIR spectrum reveals that the grown sample is a promising nonlinear optical (NLO) material. FTIR analysis confirms the functional groups present in the sample. The thermogravimetric (TG) and differential thermogravimetric (DTA) analyses ensure that the sample material is thermally stable up to 160 °C. The second harmonic efficiency of the sample is 1.3 times greater than that of standard KDP. The mechanical strength of the grown sample is estimated by Vickers microhardness tester. The electrical properties were investigated by impedance analysis and the results of various studies of the grown crystals are discussed.

  16. Cobalt-catalyzed hydroalkylation of [60]fullerene with active alkyl bromides: selective synthesis of monoalkylated fullerenes.

    Science.gov (United States)

    Lu, Shirong; Jin, Tienan; Bao, Ming; Yamamoto, Yoshinori

    2011-08-17

    The Co-catalyzed hydroalkylation of C(60) with reactive alkyl bromides 1 (RBr) in the presence of Mn reductant and H(2)O at ambient temperature gave the monoalkylated C(60) (2) in good to high yields. The use of CoLn/Mn/H(2)O under Ar atmosphere is crucial for the success of the present transformation. The reaction most probably proceeds through the Co(0 or I) complex-promoted generation of a radical (R(•)) followed by addition to C(60). This hydroalkylation method was applied to the synthesis of zinc porphyrin attached C(60) (2l), dendrimer attached C(60) (2m), and fullerene dimer (2n), which were not easily available through the previously known methods.

  17. Adsorption layer properties of alkyltrimethylammonium bromides at interfaces between water and different alkanes.

    Science.gov (United States)

    Mucic, N; Kovalchuk, N M; Aksenenko, E V; Fainerman, V B; Miller, R

    2013-11-15

    We measured the interfacial tensions of aqueous solutions against different oil phases using drop profile analysis tensiometry (PAT-1, Sinterface Technologies, Germany) for decyl- and dodecyltrimethylammonium bromide (C10TAB and C12TAB) in phosphate buffer (10 mM, pH7). The following alkanes were used as oil phases: hexane, heptane, octane, nonane, decane, dodecane and tetradecane. The obtained equilibrium interfacial tension isotherms were fitted by the Frumkin Ionic Compressibility model (FIC). The surfactants adsorb at the water/oil interface in competition with the oil molecules. At high surfactant surface coverage this competitive adsorption is manifested in two ways. First, for short chain surfactants, the oil molecules are embedded into the adsorption layer. Second, for long chain surfactants, the short alkane chains of the oil molecules are squeezed out from the adsorption layer due to strong mutual interaction between surfactants' chains. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Interaction between DNA and Trimethyl-Ammonium Bromides with Different Alkyl Chain Lengths

    Directory of Open Access Journals (Sweden)

    Chao Cheng

    2014-01-01

    Full Text Available The interaction between λ—DNA and cationic surfactants with varying alkyl chain lengths was investigated. By dynamic light scattering method, the trimethyl-ammonium bromides-DNA complex formation was shown to be dependent on the length of the surfactant’s alkyl chain. For surfactants with sufficient long alkyl chain (CTAB, TTAB, DTAB, the compacted particles exist with a size of ~60–110 nm at low surfactant concentrations. In contrast, high concentration of surfactants leads to aggregates with increased sizes. Atomic force microscope scanning also supports the above observation. Zeta potential measurements show that the potential of the particles decreases with the increase of surfactant concentration (CTAB, TTAB, DTAB, which contributes much to the coagulation of the particles. For OTAB, the surfactant with the shortest chain in this study, it cannot fully neutralize the charges of DNA molecules; consequently, the complex is looser than other surfactant-DNA structures.

  19. Fluorescence studies on the interaction of ethidium bromide with duplex, triplex and quadruplex DNA structures

    Institute of Scientific and Technical Information of China (English)

    孙雪光; 曹恩华; 何裕建; 秦静芬

    1999-01-01

    Under different conditions, oligonucleotides can form several alternative DNA structures such as duplex, triplex and quadruplex. All these structures can interact with ethidium bromide (EB) and make its fluorescence intensity change. The fluorescence spectra and other related parameters provided by static fluorescence techniques showed that the interaction mechanisms between EB and these structures were not always the same. Among them, B type duplex and triplex DNA adopt an intercalative mode when binding to the EB, which has a relatively high efficiency of energy transfer and the fluorescence of EB cannot be quenched easily. While for the parallel duplex DNA, the interaction mode is an outside binding in which energy transfer can hardly happen and its fluorescence intensity as well as Stern-Volmer constant is almost the same to the free EB. For the quadruplex, the binding mechanism to EB is more complex. Results from the energy transfer and quenching studies indicate that the two interaction modes note

  20. Improved hydrogen evolution on glassy carbon electrode modified with novel Pt/cetyltrimethylammonium bromide nanoscale aggregates

    Institute of Scientific and Technical Information of China (English)

    Jahan-Bakhsh Raoof; Sayed Reza Hosseini; Seyedeh Zeinab Mousavi-Sani

    2015-01-01

    A novel, cost‐effective, and simple electrocatalyst based on a Pt‐modified glassy carbon electrode (GCE), using cetyltrimethylammonium bromide (CTAB) as a cationic surfactant, is reported. Am‐phiphilic CTAB molecules were adsorbed on GCE by immersion in a CTAB solution. The positively charged hydrophilic layer, which consisted of small aggregates of average size less than 100 nm, was used for accumulation and complexation of [PtCl6]2− anions by immersing the electrode in K2PtCl6 solution. The modified electrode was characterized using scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, impedance spectroscopy, and electrochemical methods. The electrocatalytic activity of the Pt particles in the hydrogen evolution reaction (HER) was investigat‐ed. The results show that the CTAB surfactant enhances the electrocatalytic activity of the Pt parti‐cles in the HER in acidic solution.

  1. Flotation de-silicating from diasporic-bauxite with cetyl trimethylammonium bromide

    Institute of Scientific and Technical Information of China (English)

    王毓华; 胡岳华; 刘晓文

    2003-01-01

    Using cetyl trimethylammonium bromide (CTAB) as collector, the flotation de-silicating from diasporicbauxite was investigated. And the Zeta potentials and contact-angles of silicate minerals and diaspore were also stuite and illite become more positive, and the contact angles of these three silicates also increase evidently in the pH range of 2-8, but the Zeta potentials and contact angles of diaspore change little. So, the floatability of the four minerals is in the following order: pyrophyllite>kaolinite≈illite>diaspore. The open-circuit flotation results also show that a bauxite concentrate with m(Al2 O3 )/m(SiO2 ) over 9.3 and Al2 O3 recovery over 76% can be obtained from diasporic-bauxite ore. The result of XRD of the bauxite concentrate shows that pyrophyllite is easier to be removed from diasporic-bauxite than illite and kaolinite due to its better floatability.

  2. Suzuki Reaction of Aryl Bromides Using a Phosphine-Free Magnetic Nanoparticle-Supported Palladium Catalyst

    Institute of Scientific and Technical Information of China (English)

    Nghia T. BUI; Trung B. DANG; Ha V. LE; Nam T. S. PHAN

    2011-01-01

    A palladium catalyst immobilized on superparaganetic nanoparticles was prepared with a palladium loading of 0.30 mmol/g.The catalyst was characterized using X-ray diffraction,scanning electron microscopy,transmission electron microscopy,vibrating sample magnetometry,thermogravimetric analysis,Fourier transform infrared,atomic absorption spectrophotometry,and nitrogen adsorption.The immobilized palladium catalyst was an efficient catalyst without added phosphine ligands for the Suzuki cross-coupling reaction of several aryl bromides with phenylboronic acid.The recovery of catalyst was simply by magnetic decantation in the presence of a magnet.The immobilized palladium catalyst can be reused many times without significant degradation in catalytic activity.No leaching of active palladium species into the reaction solution was detected.

  3. Lithium bromide absorption machines: Pressure drop and mass transfer in solutions conical sheets

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, E. [Escuela Universitaria de Ingenieria Tecnica Industrial, U.P.M., Ronda de Valencia 3, Madrid 28012 (Spain); Izquierdo, M. [Instituto de Ciencias de la Construccion Eduardo Torroja. C.S.I.C., Serrano Galvache 4, Madrid 28033 (Spain); Lizarte, R. [Escuela Politecnica Superior, Universidad Carlos III de Madrid, Avda. de la Universidad 30, Madrid 28911 (Spain); Marcos, J.D. [Escuela Tecnica Superior de Ingenieria Industrial, U.N.E.D., Juan del Rosal 12, Madrid 28040 (Spain)

    2009-07-15

    Adiabatic vapour absorption in conical liquid sheets is studied with a view to use in air conditioning. The sheets consist in a lithium bromide aqueous solution sprayed at mass flow rates ranging from 0.0078 to 0.0116 kg/s (28-42 kg/h). The experimental results show that the deformation rate associated with conical sheet development has a significant effect on absorption, with 60% of the total reached by the time the liquid sheet disintegrates, 4 ms after injection. In the conical sheet configuration, about 150 g of vapour are absorbed per kJ of solution flow work. The vapour absorption rate per chamber absorption volume, in turn, is found to be over 1 g/s l in absorption chambers 75 mm long or less. (author)

  4. Metal-enhanced ethidium bromide emission: Application to dsDNA detection

    Science.gov (United States)

    Dragan, A. I.; Bishop, E. S.; Strouse, R. J.; Casas-Finet, J. R.; Schenerman, M. A.; Geddes, C. D.

    2009-10-01

    Ethidium bromide (EB) is a commonly used probe for fluorescence detection and quantification of nucleic acids, since EB forms a highly luminescent complex with dsDNA. Typical detection sensitivity of EB-based assays to dsDNA in solution is about 0.1 μg. With the aim to increase the sensitivity of EB assays we have employed the Metal-Enhanced Fluorescence technology. We show that deposition of the EB/DNA complex solutions onto the silver nanoparticle surface additionally increases the far-field observable fluorescence ≈5-fold, yielding a net fluorescence enhancement factor of ≈180-fold, as compared to the free dye in solution. Subsequently, our approach enables the more sensitive detection of dsDNA.

  5. Spectroscopic probe of the competitive binding of ethidium bromide and neomycin to DNA

    Science.gov (United States)

    Pal, Medini Kanta; Ghosh, Jimut Kanti

    1995-03-01

    The three spectroscopic changes of ethidium bromide (EB) on its binding to DNA, namely red-shift of the νmax, enhancement of fluorescence and induced dichroism are utilized to study the competitive binding of neomycin (NMC) and EB to DNA. Reversion of νmax, decrease in fluorescence and reduction of dichroism of DNA-EB on addition of NMC shows that the binding of NMC and EB to DNA is competitive in nature, over a limited concentration of the polymer. The binding constant of EB-DNA falls from 4.00 × 10 6 to 2.27 × 10 4 1 mol -1 in the presence of added NMC.

  6. A New, More Stable Polymorphic Form of Otilonium Bromide: Solubility, Crystal Structure, and Phase Transformation.

    Science.gov (United States)

    Vega, Daniel R; Halac, Emilia; Segovia, Luciano; Baggio, Ricardo

    2016-10-01

    A new polymorphic form of otilonium bromide is presented (Form I), and a thorough analysis of its crystal and molecular structure is performed. The compound suffers a temperature-driven first-order phase transition at about 396 K, which transforms it into the polymorph reported by Dapporto P and Sega A (Acta Cryst. 1986;C42:474-478) (Form II). Through thermal analysis and solubility experiments the relative stability of both crystal modifications were determined, confirming that at room temperature this new Form I is the more stable one, Form II existing just in a metastable state. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  7. [The otilonium bromide-benzodiazepine combination in the therapy of the irritable colon syndrome].

    Science.gov (United States)

    Capurso, L; Del Sette, F; Ferrario, F; Tarquini, M

    1992-08-01

    The irritable bowel syndrome is classified ad "disturbance of intestinal motility without an identifiable anatomic substrate". However, the clear etiopathogenetic implications of a psychosomatic nature complicate the search for an adequate therapeutic strategy. Based on this clinical experience, we set out to check the importance of a spasmolytic with a benzodiazepine and the tolerability of this type of combination. We therefore compared the results in 60 patients with irritable bowel syndrome of 8 weeks' treatment with tablets containing octylonium bromide (OB) 20 mg plus diazepam (DZ) 2 mg or OB 40 mg + 2 mg DZ. The doubling of the spasmolytic without increasing the daily dose of anxiolytic appeared to be useful for reducing the symptoms typical for the irritable bowel syndrome. In addition, the combination was found to be perfectly tolerated.

  8. Determination of critical micelle concentration of cetyltrimethylammonium bromide: Different procedures for analysis of experimental data

    Directory of Open Access Journals (Sweden)

    Goronja Jelena M.

    2016-01-01

    Full Text Available Conductivity of two micellar systems was measured in order to determine critical micelle concentration (CMC of cetyltrimethylammonium bromide (CTAB. Those systems were: CTin water and CTin binary mixture acetonitrile (ACN-water. Conductivity (κ-concentration (c data were treated by four different methods: conventional method, differential methods (first and second derivative and method of integration (methods A-D, respectively. As CTin water micellar system shows a sharp transition between premicellar and postmicellar part of the κ/c curve, any of the applied methods gives reliable CMC values and there is no statistically significant difference between them. However, for CTin ACN-water mixture micellar system the integration method for CMC determination is recommended due to a weak curvature of κ/c plot.

  9. Pitting corrosion transformation of SUS304 stainless steel in lithium bromide solution at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.X.; Ma, X.H.; Chen, J.B.; Bo, S.S. [Institute of Chemical Engineering, Dalian University of Technology, Dalian (China)

    2009-05-15

    The foundational data and rules of SUS304 corrosion in aqueous lithium bromide solution at 150-200 C have been investigated by means of weight loss in this paper. The Taguchi method was chosen to investigate the effects of variables on corrosion at higher temperature. Concentration of dissolved oxygen was controlled by keeping the vessel pressure at 1.3 kPa (absolute) before the experiment. The results showed that there was a transformation tendency from pitting corrosion to general corrosion and transition concentration of pitting and film corrosion decreased with increase in solution temperature. The adsorption, activity, and diffusivity of bromine ion led to different corrosion modalities. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  10. Strain IMB-1, a novel bacterium for the removal of methyl bromide in fumigated agricultural soils

    Science.gov (United States)

    Connell, Hancock T.L.; Costello, A.M.; Lidstrom, M.E.; Oremland, R.S.

    1998-01-01

    A facultatively methylotrophic bacterium, strain IMB-1, that has been isolated from agricultural soil grows on methyl bromide (MeBr), methyl iodide, methyl chloride, and methylated amines, as well as on glucose, pyruvate, or acetate. Phylogenetic analysis of its 16S rRNA gene sequence indicates that strain IMB-1 classes in the alpha subgroup of the class Proteobacteria and is closely related to members of the genus Rhizobium. The ability of strain IMB-1 to oxidize MeBr to CO2 is constitutive in cells regardless of the growth substrate. Addition of cell suspensions of strain IMB-1 to soils greatly accelerates the oxidation of MeBr, as does pretreatment of soils with low concentrations of methyl iodide. These results suggest that soil treatment strategies can be devised whereby bacteria can effectively consume MeBr during field fumigations, which would diminish or eliminate the outward flux of MeBr to the atmosphere.

  11. Viscosity B Coefficients of Some Tetraalkylammonium Bromides, Lithium Tetrafluoroborate and Tetrabutylammonium Tetraphenyl borate in Propylene Carbonate

    Science.gov (United States)

    Muhuri, Prakash K.; Hazra, Dilip K.

    1993-03-01

    The viscosities of solutions of tetraalkylammonium bromides, R4NBr (R = -C2H5 to -C7H15), lithium tetrafluoroborate (LiBF4) and tetrabutylammonium tetraphenylborate (Bu4NBPh4) in propylene carbonate (PC) have been measured at 25, 35 and 45 °C. The relative viscosities have been analyzed using the Jones-Dole equation in the form of unassociated electrolytes, and the viscosity B-coefficients have been evaluated. The thermodynamic parameters have been calculated using the transition-state treatment and the measured temperature dependencies. Ionic B values have also been derived and discussed in terms of Einstein's equation. The analysis shows that Li+ is highly solvated compared to other cations and anions in this medium.

  12. Exchange equilibria between bicarbonate, carbonate, chloride and bromide on dowex 1 x 8.

    Science.gov (United States)

    Lundström, U; Olin, A

    1984-07-01

    The exchange reaction 2R(+)HCO(3)(2-) + CO(3)(2-) right harpoon over left harpoon R(2)(+) CO(3)(2-) + 2HCO(3)(2-) has been studied on Dowex 1 x 8 in the presence of bicarbonate solution in equilibrium with atmospheric carbon dioxide (open system). The experiments showed, as theory predicts, that the composition of the resin phase is independent of the concentration of the bicarbonate solution. The mole fraction of carbonate at equilibrium is about 0.4 and the equilibrium constant is 0.15M at 20 degrees . With this value of the constant, the composition of the ion-exchanger for various bicarbonate concentrations has been calculated for a closed system. At [HCO(3)(-)] Chromatographie enrichment of bromide from fresh water.

  13. Characterization of potassium bromide crystals grown in the aqueous solution of picric acid

    Science.gov (United States)

    Maheswari, J. Uma; Krishnan, C.; Kalyanaraman, S.; Selvarajan, P.

    2016-12-01

    Potassium bromide crystals were grown in the aqueous solution of picric acid by slow evaporation technique at room temperature. X-ray Diffraction (XRD) analysis ensures that the grown sample is in Fm3m space group and FCC structure. Energy Dispersive X-ray Spectroscopy (EDX) reveals the presence of elements in the title compound. UV-Vis-NIR spectrum reveals that the grown sample is a promising nonlinear optical (NLO) material. FTIR analysis confirms the functional groups present in the sample. The thermogravimetric (TG) and differential thermogravimetric (DTA) analyses ensure that the sample material is thermally stable up to 160 °C. The second harmonic efficiency of the sample is 1.3 times greater than that of standard KDP. The mechanical strength of the grown sample is estimated by Vickers microhardness tester. The electrical properties were investigated by impedance analysis and the results of various studies of the grown crystals are discussed.

  14. Growth, photoluminescence, thermal and mechanical behaviour of Ethyltriphenylphosphonium bromide dihydrate crystal

    Science.gov (United States)

    Parthasarathy, M.; Gopalakrishnan, R.

    2013-10-01

    Single crystal of Ethyltriphenylphosphonium bromide dihydrate (ETPB) was grown by slow evaporation solution growth technique. The grown crystal was confirmed by single crystal X-ray diffraction. The functional groups and vibrational frequencies were identified using FT-IR and FT-Raman spectral analyses. Optical properties were studied by UV-Visible and photoluminescence spectroscopic techniques to explore its efficacy towards device fabrication. Thermal characteristics of ETPB were studied using the TGA/DTA and DSC response curves. The mechanical behaviour of the grown crystal was studied using Vicker's microhardness tester and the work hardening coefficient was evaluated. The second harmonic generation of the title compound was tested by Kurtz-Perry powder technique.

  15. Growth and characterization of Cadmium Thiosemicarbazide Bromide crystals for antibacterial and nonlinear optical applications

    Science.gov (United States)

    Thomas Joseph Prakash, J.; Martin Sam Gnanaraj, J.

    2015-01-01

    Semiorganic nonlinear optical crystals of Cadmium Thiosemicarbazide Bromide was grown by slow evaporation solution growth technique. The unit cell parameters were estimated by subjecting the crystals to single crystal X-ray diffraction. The grown crystals were subjected to Powder X-ray diffraction for analyzing the crystalline nature of the sample. FTIR studies reveal the functional groups and the optical characters were analyzed by UV-Vis spectral studies. Mechanical stability of the sample was assessed by Vicker's micro hardness test. The presence of surface dislocations was identified by chemical etching technique. Antibacterial study was carried out against ACDP declared harmful pathogens. SHG efficiency of CTSB crystal was tested using Nd: YAG laser and it was found to be ∼1.8 times that of potassium dihydrogen phosphate.

  16. Bromidotetra-kis-(1H-2-ethyl-5-methyl-imidazole-κN)copper(II) bromide.

    Science.gov (United States)

    Godlewska, Sylwia; Baranowska, Katarzyna; Socha, Joanna; Dołęga, Anna

    2011-12-01

    The Cu(II) ion in the title compound, [CuBr(C(6)H(10)N(2))(4)]Br, is coordinated in a square-based-pyramidal geometry by the N atoms of four imidazole ligands and a bromide anion in the apical site. Both the Cu(II) and Br(-) atoms lie on a crystallographic fourfold axis. In the crystal, the [CuBr(C(6)H(10)N(2))(4)](+) complex cations are linked to the uncoordinated Br(-) anions (site symmetry [Formula: see text]) by N-H⋯Br hydrogen bonds, generating a three-dimensional network. The ethyl group of the imidazole ligand was modelled as disordered over two orientations with occupancies of 0.620 (8) and 0.380 (8).

  17. Bromidotetrakis(1H-2-ethyl-5-methylimidazole-κN3copper(II bromide

    Directory of Open Access Journals (Sweden)

    Sylwia Godlewska

    2011-12-01

    Full Text Available The CuII ion in the title compound, [CuBr(C6H10N24]Br, is coordinated in a square-based-pyramidal geometry by the N atoms of four imidazole ligands and a bromide anion in the apical site. Both the CuII and Br− atoms lie on a crystallographic fourfold axis. In the crystal, the [CuBr(C6H10N24]+ complex cations are linked to the uncoordinated Br− anions (site symmetry overline{4} by N—H...Br hydrogen bonds, generating a three-dimensional network. The ethyl group of the imidazole ligand was modelled as disordered over two orientations with occupancies of 0.620 (8 and 0.380 (8.

  18. The matlockite-type praseodymium(III oxide bromide PrOBr

    Directory of Open Access Journals (Sweden)

    Pia Talmon-Gros

    2011-12-01

    Full Text Available The crystal structure of the praseodymium(III oxide bromide, PrOBr, can be best described with layers of agglomerated square antiprisms [PrO4Br4]9−. These slabs are stacked along the c axis and linked via two different secondary contacts between Pr3+ and Br−. The Pr3+ cations occupy the Wyckoff site 2c with 4mm symmetry and carry four O2− anions as well as four primary Br− anions, yielding a coordination number of 8. While the Br− anions exhibit the same site symmetry as the Pr3+ cations, the oxide anions are located at the Wyckoff position 2a with site symmetry overline{4}m2 and have four Pr3+ cations as neighbours, defining a tetrahedron.

  19. Tetrabutylammonium Bromide (TBABr-Based Deep Eutectic Solvents (DESs and Their Physical Properties

    Directory of Open Access Journals (Sweden)

    Rizana Yusof

    2014-06-01

    Full Text Available Density, viscosity and ionic conductivity data sets of deep eutectic solvents (DESs formed by tetrabutylammonium bromide (TBABr paired with ethlyene glycol, 1,3-propanediol, 1,5-pentanediol and glycerol hydrogen bond donors (HBDs are reported. The properties of DES were measured at temperatures between 303 K and 333 K for HBD percentages of 66.7% to 90%. The effects of HBDs under different temperature and percentages are systematically analyzed. As expected, the measured density and viscosity of the studied DESs decreased with an increase in temperature, while ionic conductivity increases with temperature. In general, DESs made of TBABr and glycerol showed the highest density and viscosity and the lowest ionic conductivity when compared to other DESs. The presence of an extra hydroxyl group on glycerol in a DES affected the properties of the DES.

  20. Crystal structure of {2-[({2-[(2-aminoethylamino]ethyl}iminomethyl]phenolato}aquacopper(II bromide

    Directory of Open Access Journals (Sweden)

    Nataliya I. Plyuta

    2014-09-01

    Full Text Available In the mononuclear copper(II title complex, [Cu(C11H16N3O(H2O]Br, the CuII atom is coordinated by one O and three N atoms of the Schiff base ligand that forms together with one water molecule a slightly distorted [CuN3O2] square-pyramidal polyhedron. The deviation of the CuII atom from the mean equatorial plane is 0.182 (2 Å. The equatorial plane is nearly coplanar to the aromatic ring of the ligand [angle between planes = 10.4 (1°], and the water molecule is situated in the apical site. All coordinating atoms (except the imine nitrogen and the bromide ion contribute to the formation of the N—H...Br, O—H...Br and O—H...O hydrogen bonds, which link molecules into chains along [01-1].

  1. Methyl-β-Cyclodextrin /Cetyltrimethyl Ammonium Bromide Synergistic Sensitized Fluorescence Method for the Determination of Levofloxacin.

    Science.gov (United States)

    Ren, Qiuyi; Zhu, Xiashi

    2016-03-01

    A novel method of methyl-β-cyclodextrin (methyl-β-CD) and cetyltrimethyl ammonium bromide (CTAB) synergistic sensitized fluorescence analysis to determine levofloxacin (LVFX) was developed. The results were shown that the fluorescence intensity of LVFX was increased a lot in the system of methyl-β-cyclodextrin-CTAB medium. Under the conditions of λ(ex/em )= 330/507 nm and pH 4.5, the linear range and the detection limit for LVFX were found to be 0.040 ~ 4.0 μg/mL and 0.3 ng/mL, respectively. The mechanism of sensitized fluorescence method was discussed by the solubilization capacity and the microenvironment of medium. The proposed method has been applied for the determination of LVFX in eye drops real samples and human serum with satisfactory recovery.

  2. Copper bromide vapor brightness amplifiers with 100 kHz pulse repetition frequency

    Science.gov (United States)

    Trigub, M. V.; Evtushenko, G. S.; Torgaev, S. N.; Shiyanov, D. V.; Evtushenko, T. G.

    2016-10-01

    The paper presents a laser monitor with 10 μs time-resolution based on a high-frequency copper bromide vapor brightness amplifier. A sync circuit has been designed for single-pulse imaging. The analysis of amplifying characteristics of the active elements and active optical system (laser monitor) parameters allowed to determine the optimal concentration of HBr at which the images can be obtained with minimum distortions. For the active element operating at high frequencies (more than 50 kHz) as a brightness amplifier, the concentration of HBr must be lower than that needed for obtaining the maximum output power. The limiting brightness temperature of the background radiation which does not affect the image quality is determined. The potential feasibility of using a proposed brightness amplifier for visualizing processes blocked from viewing by the background radiation with the brightness temperature up to 8000 K is demonstrated.

  3. INTERACTION OF POLY(SODIUM SULFODECYL METHACRYLATE) WITH CETYLTRIMETHYL AMMONIUM BROMIDE IN AQUEOUS SOLUTION

    Institute of Scientific and Technical Information of China (English)

    Cong-hua Lu; Chuan-qiou Luo; Wei-xiao Cao

    2003-01-01

    The interaction of poly(sodium sulfodecyl methacrylate) (PSSM) with cetyltrimethyl ammonium bromide (CTAB)was studied. It was found that the precipitate formed from PSSM and CTAB will be dissolved by excessive CTAB, resultingin the appearance of two maxima of the solution viscosity at the molar ratio (CTAB/-SO3-) of ≈ 0.68 and ≈ 1.30,respectively. The first one is related closely to the aggregation of polymer chains via CTAB molecules and the second oneshould be ascribed to the formation of the mixed micelles comprising surfactant and the polymer's hydrophobic chains. Theeffect of NaCl on the viscosity, the transmittance of the aqueous solution and the solubility of oil-soluble dye (dimethylyellow) in the mixed system were also investigated.

  4. Rapid isolation of plasmid DNA by LiCl-ethidium bromide treatment and gel filtration.

    Science.gov (United States)

    Kondo, T; Mukai, M; Kondo, Y

    1991-10-01

    We established a simple and rapid plasmid DNA purification method. Crude plasmid DNA preparations are treated with 4 M LiCl in the presence of 0.6 mg/ml ethidium bromide to precipitate RNA and proteins contained in the DNA preparations. After removal of RNA and protein precipitates, the supernatant is filtered through a Sepharose CL6B column to remove low-molecular-weight contaminants. This procedure takes only 30 min and provides pure plasmid DNA preparations that consist mainly of covalently closed circular plasmid DNA but have no detectable RNA and protein. The purified DNA preparations are susceptible to various six- and four-base-recognition restriction endonucleases, T4 DNA ligase, the Klenow fragment of DNA polymerase I, and T7 and Taq DNA polymerase. Since no special equipment is needed for this purification method, 20 or more samples of microgram to milligram levels can be treated in parallel.

  5. Successful treatment of migrating partial seizures in Wolf-Hirschhorn syndrome with bromide.

    Science.gov (United States)

    Itakura, Ayako; Saito, Yoshiaki; Nishimura, Yoko; Okazaki, Tetsuya; Ohno, Koyo; Sejima, Hitoshi; Yamamoto, Toshiyuki; Maegaki, Yoshihiro

    2016-08-01

    A girl with mild psychomotor developmental delay developed right or left hemiclonic convulsion at 10months of age. One month later, clusters of hemiclonic or bilateral tonic seizures with eyelid twitching emerged, resulting in status epilepticus. Treatment with phenobarbital and potassium bromide completely terminated the seizures within 10days. Ictal electroencephalography revealed a migrating focus of rhythmic 3-4Hz waves from the right temporal to right frontal regions and then to the left frontal regions. Genetic analysis was conducted based on the characteristic facial appearance of the patient, which identified a 2.1-Mb terminal deletion on chromosome 4p. This is the first case of Wolf-Hirschhorn syndrome complicated by epilepsy with migrating partial seizures.

  6. Multimetallic catalysed cross-coupling of aryl bromides with aryl triflates.

    Science.gov (United States)

    Ackerman, Laura K G; Lovell, Matthew M; Weix, Daniel J

    2015-08-27

    The advent of transition-metal catalysed strategies for forming new carbon-carbon bonds has revolutionized the field of organic chemistry, enabling the efficient synthesis of ligands, materials, and biologically active molecules. In cases where a single metal fails to promote a selective or efficient transformation, the synergistic cooperation of two distinct catalysts--multimetallic catalysis--can be used instead. Many important reactions rely on multimetallic catalysis, such as the Wacker oxidation of olefins and the Sonogashira coupling of alkynes with aryl halides, but this approach has largely been limited to the use of metals with distinct reactivities, with only one metal catalyst undergoing oxidative addition. Here, we demonstrate that cooperativity between two group 10 metal catalysts--(bipyridine)nickel and (1,3-bis(diphenylphosphino)propane)palladium--enables a general cross-Ullmann reaction (the cross-coupling of two different aryl electrophiles). Our method couples aryl bromides with aryl triflates directly, eliminating the use of arylmetal reagents and avoiding the challenge of differentiating between multiple carbon-hydrogen bonds that is required for direct arylation methods. Selectivity can be achieved without an excess of either substrate and originates from the orthogonal reactivity of the two catalysts and the relative stability of the two arylmetal intermediates. While (1,3-bis(diphenylphosphino)propane)palladium reacts preferentially with aryl triflates to afford a persistent intermediate, (bipyridine)nickel reacts preferentially with aryl bromides to form a transient, reactive intermediate. Although each catalyst forms less than 5 per cent cross-coupled product in isolation, together they are able to achieve a yield of up to 94 per cent. Our results reveal a new method for the synthesis of biaryls, heteroaryls, and dienes, as well as a general mechanism for the selective transfer of ligands between two metal catalysts. We anticipate that this

  7. The aqueous catanionic system sodium perfluorooctanoate-dodecyltrimethylammonium bromide at low concentration.

    Science.gov (United States)

    López-Fontán, José Luis; Blanco, Elena; Ruso, Juan M; Prieto, Gerardo; Schulz, Pablo C; Sarmiento, Félix

    2007-08-15

    The interaction between sodium perfluorooctanoate (SPFO) and dodecyltrimethylammonium bromide (DTAB) was studied by several methods and it was found strongly synergistic. Above a mole fraction of SPFO in the surfactant mixture (alpha(SPFO))=0.38, the interaction is repulsive and increases with the content of SPFO in both, the overall mixture and micelles, whereas the interaction is attractive if DTAB is in excess. At alpha(SPFO)=0.38 the low miscibility between hydrocarbon and fluorocarbon is counterbalanced by the electrostatic attraction between the opposite charged head groups, and the micelle composition is ideal (i.e., the mole fraction of SPFO in micelles X(SPFO)=alpha(SPFO)=0.38). The solubility of fluorocarbon in hydrocarbon is lower than that of hydrocarbon in fluorocarbon. Micelles of DTAB act as a solvent for SPFO without important structural changes, whilst micelles of SPFO undergo important changes when dissolve DTAB. This asymmetry may be interpreted as caused by the difference in chain length that favors the inclusion of the shorter chain in micelles of the longer surfactant, but disfavors the opposite process. Above X(SPFO)=0.5 there is an excess adsorption of bromide ions on the mixed micelles surface, giving rise to a high zeta potential. Micelles of pure SPFO or pure DTAB show an important energy barrier which prevents micelle flocculation. The inclusion of SPFO in DTAB micelles produces a reduction of the energy barrier, which disappeared when alpha(SPFO)=0.5. This produces the flocculation of micelles giving rise to the formation of a non-birefringent coacervate, which is probably formed by unordered isometric clusters of micelles.

  8. Role of combined indacaterol and glycopyrronium bromide (QVA149 for the treatment of COPD in Japan

    Directory of Open Access Journals (Sweden)

    Horita N

    2015-04-01

    Full Text Available Nobuyuki Horita, Takeshi Kaneko Department of Pulmonology, Yokohama City University Graduate School of Medicine, Yokohama, Japan Abstract: Once-daily dual-bronchodilator therapy with combined indacaterol and glycopyrronium bromide in one device (Ultibro, Breezhaler, often called QVA149, was first approved in 2013 in Japan and Europe. As of November 2014, more than 40 countries had approved this medication except for the USA. This is the first dual bronchodilator in one device. Now, the Breezhaler is the only device that can provide long-acting muscarinic antagonist (glycopyrronium bromide, long-acting beta agonist (indacaterol, and a combination of the two medications (QVA149. The choice among the three medications allows a patient to use the same inhalation device even when the regimen is changed from single-bronchodilator therapy to dual-bronchodilator therapy. In addition, the quick bronchodilation effect and once-daily administration can improve patient adherence to medical treatment for chronic obstructive pulmonary disease (COPD. To our knowledge, as of November 2014, the safety and the efficacy of QVA149 have been evaluated in 14 randomized controlled trials. The 14 trials generally showed good safety profiles, and there were better or not-inferior bronchodilator effects of QVA149 when compared with placebo, or other inhaled medication. According to the Japanese Respiratory Society guidelines, QVA149 is a combination of the two first-line bronchodilators. Our meta-analysis indicated that QVA149 is superior to the salmeterol–fluticasone combination to treat COPD in respect of the frequency of adverse effects, exacerbation, pneumonia, and improvement of trough forced expiratory volume in 1 second (FEV1. Thus, we believe that QVA149 can be a key medication for COPD treatments. Keywords: bronchodilator agents, dry powder inhalers, delivery of health care, guideline, meta-analysis, muscarinic antagonists 

  9. Role of once-daily glycopyrronium bromide (NVA237 in the management of COPD

    Directory of Open Access Journals (Sweden)

    D’Urzo A

    2013-08-01

    Full Text Available Anthony D'UrzoDepartment of Family and Community Medicine, University of Toronto, Toronto, ON, CanadaAbstract: Progressive airflow limitation is a hallmark feature of chronic obstructive pulmonary disease (COPD that ultimately leads to breathlessness, impaired quality of life, and reduced exercise capacity. Pharmacotherapy is used in patients with COPD to prevent and control symptoms, reduce both the frequency and severity of exacerbations, improve health status, and increase exercise tolerance. These strategies are intended to address management issues which promote both current disease control and a reduction in the risk of disease deterioration in the future. At the present time, long-acting β2-agonists (LABAs and long-acting muscarinic antagonists (LAMAs are available for maintenance therapy in patients with persistent symptoms. Tiotropium was the first LAMA to be approved for management of COPD, and many studies have described its beneficial effects on multiple clinically relevant outcomes. Glycopyrronium bromide (NVA237, a new LAMA, has been developed and received regulatory approval for management of COPD in a number of countries around the world. Results from pivotal Phase III trials suggest that NVA237 is safe and well tolerated in patients with moderate to severe COPD, and provides rapid and sustained improvements in lung function. Further, these changes are associated with statistically and clinically meaningful improvements in dyspnea, health-related quality of life, and exercise tolerance. Treatment with NVA237 also results in a significant reduction in risk of exacerbations and the need for rescue medication, and has been comparable with tiotropium with respect to safety and efficacy outcomes. Finally, emerging data indicate that NVA237 is efficacious both as monotherapy and in combination with indacaterol.Keywords: glycopyrronium bromide, NVA237, chronic obstructive pulmonary disease, inhaled long-acting bronchodilators

  10. Multimetallic catalysed cross-coupling of aryl bromides with aryl triflates

    Science.gov (United States)

    Ackerman, Laura K. G.; Lovell, Matthew M.; Weix, Daniel J.

    2015-08-01

    The advent of transition-metal catalysed strategies for forming new carbon-carbon bonds has revolutionized the field of organic chemistry, enabling the efficient synthesis of ligands, materials, and biologically active molecules. In cases where a single metal fails to promote a selective or efficient transformation, the synergistic cooperation of two distinct catalysts--multimetallic catalysis--can be used instead. Many important reactions rely on multimetallic catalysis, such as the Wacker oxidation of olefins and the Sonogashira coupling of alkynes with aryl halides, but this approach has largely been limited to the use of metals with distinct reactivities, with only one metal catalyst undergoing oxidative addition. Here, we demonstrate that cooperativity between two group 10 metal catalysts--(bipyridine)nickel and (1,3-bis(diphenylphosphino)propane)palladium--enables a general cross-Ullmann reaction (the cross-coupling of two different aryl electrophiles). Our method couples aryl bromides with aryl triflates directly, eliminating the use of arylmetal reagents and avoiding the challenge of differentiating between multiple carbon-hydrogen bonds that is required for direct arylation methods. Selectivity can be achieved without an excess of either substrate and originates from the orthogonal reactivity of the two catalysts and the relative stability of the two arylmetal intermediates. While (1,3-bis(diphenylphosphino)propane)palladium reacts preferentially with aryl triflates to afford a persistent intermediate, (bipyridine)nickel reacts preferentially with aryl bromides to form a transient, reactive intermediate. Although each catalyst forms less than 5 per cent cross-coupled product in isolation, together they are able to achieve a yield of up to 94 per cent. Our results reveal a new method for the synthesis of biaryls, heteroaryls, and dienes, as well as a general mechanism for the selective transfer of ligands between two metal catalysts. We anticipate that this

  11. Direct palladium-catalyzed arylations of aryl bromides with 2/9-substituted pyrimido[5,4-b]indolizines.

    Science.gov (United States)

    Jiang, Min; Li, Ting; Meng, Linghua; Yang, Chunhao; Xie, Yuyuan; Ding, Jian

    2009-01-01

    C-5 arylated 2/9-substituted pyrimido[5,4-b]indolizines were synthesized via palladium-catalyzed direct arylation. A variety of substituents on both pyrimido[5,4-b]indolizines and aryl/heteroaryl bromides are tolerated, providing rapid access to substituted pyrimido[5,4-b]indolizines in good to excellent yields.

  12. FLUORESCENCE PROBING OF THE FORMATION OF HYDROPHOBIC MICRODOMAINS BY CROSS-LINKED POLY(ALKYLMETHYLDIALLYLAMMONIUM BROMIDES) IN AQUEOUS-SOLUTION

    NARCIS (Netherlands)

    WANG, GJ; ENGBERTS, J B F N

    Pyrene has been used as a fluorescence probe to investigate the conformational behavior of cross-linked poly(alkylmethyldiallylammonium bromides) in aqueous solutions. Binding of pyrene to hydrophobic microdomains, formed by the polysoaps, is reflected by a change in the ratio I-1/I-3 of the

  13. Regio- and Enantioselective Copper-Catalyzed Allylic Alkylation of Ortho-Substituted Cinnamyl Bromides with Grignard Reagents

    NARCIS (Netherlands)

    van der Molen, Nathalie C; Tiemersma-Wegman, Theodora D; Fañanás-Mastral, Martín; Feringa, Ben L

    2015-01-01

    A highly efficient method for the copper-catalyzed asymmetric allylic alkylation of ortho-substituted cinnamyl bromides with Grignard reagents is reported. The use of a catalytic system comprising CuBr center dot SMe2 and TaniaPhos as chiral ligands gives rise to a range of branched products with

  14. Nickel-catalyzed cross-coupling reactions of benzylic zinc reagents with aromatic bromides, chlorides and tosylates.

    Science.gov (United States)

    Schade, Matthias A; Metzger, Albrecht; Hug, Stephan; Knochel, Paul

    2008-07-14

    Benzylic zinc reagents prepared by direct insertion of zinc to benzylic chlorides in the presence of LiCl undergo smooth cross-coupling reactions with aromatic chlorides, bromides and tosylates using Ni(acac)(2) and PPh(3) as a catalyst system.

  15. FLUORESCENCE SPECTROSCOPIC STUDY OF THE FORMATION OF HYDROPHOBIC MICRODOMAINS IN AQUEOUS-SOLUTIONS OF POLY(ALKYLMETHYLDIALLYLAMMONIUM BROMIDES)

    NARCIS (Netherlands)

    YANG, YJ; Engberts, Jan B F N

    The conformational state of poly(alkylmethyldiallylammonium bromides) was studied in aqueous solutions using pyrene as a fluorescence probe. The results are indicative for the formation of hydrophobic microdomains in the case of several copolymers which possess sufficiently hydrophobic alkyl side

  16. Visible light-photocatalysed carbazole synthesis via a formal (4+2) cycloaddition of indole-derived bromides and alkynes.

    Science.gov (United States)

    Yuan, Zhi-Guang; Wang, Qiang; Zheng, Ang; Zhang, Kai; Lu, Liang-Qiu; Tang, Zilong; Xiao, Wen-Jing

    2016-04-14

    We successfully developed an unprecedented route to carbazole synthesis through a visible light-photocatalysed formal (4+2) cycloaddition of indole-derived bromides and alkynes. This novel protocol features extremely mild conditions, a broad substrate scope and high reaction efficiency.

  17. Hydrobromination of alkenes with PBr3/SiO2: a simple and efficient regiospecific preparation of alkyl bromides

    Directory of Open Access Journals (Sweden)

    Sanseverino Antonio M.

    2001-01-01

    Full Text Available The reaction of several alkenes with 0.4 mol equiv. PBr3/SiO2 in dichloromethane at room temperature gave the alkyl bromides with Markovnikov regiospecificity in 50 - 100% yield and short reaction time. Isoprene at - 8 °C in these conditions gave 1-bromo-3-methyl-2-butene only (54%.

  18. C-N Coupling of nitrogen nucleophiles with aryl and heteroaryl bromides using aminoarenethiolato-copper(I) (pre-)catalyst

    NARCIS (Netherlands)

    Sperotto, Elena; Klink, Gerard P.M. van; Vries, Johannes G. de; Koten, Gerard van

    2010-01-01

    The activity of a library of 2-aminoarenethiolato-copper(I) (CuSAr) (pre-)catalyst was explored in the arylation reaction of amines and N-containing heterocycles with aryl and heteroaryl bromides, respectively. These CuSAr pre-catalysts are thermally stable, are soluble in common organic solvents

  19. Efficient, regioselective palladium-catalyzed tandem Heck-isomerization reaction of aryl bromides and non-allylic benzyl alcohols.

    Science.gov (United States)

    Crawley, Matthew L; Phipps, Kristin M; Goljer, Igor; Mehlmann, John F; Lundquist, Joseph T; Ullrich, John W; Yang, Cuijian; Mahaney, Paige E

    2009-03-05

    An efficient and mild method to couple aryl bromides and activated non-allylic alcohols in a Heck reaction with tandem isomerization to selectively afford high yields of 1,5-diarylalkan-1-ones has been developed. Mechanistic insight was gained through NMR studies of products derived from deuterium-labeled intermediates.

  20. C-H activation dependent Pd-catalyzed carbonylative coupling of (hetero)aryl bromides and polyfluoroarenes.

    Science.gov (United States)

    Lian, Zhong; Friis, Stig D; Skrydstrup, Troels

    2015-02-04

    The carbonylative coupling of aryl and heteroaryl bromides with polyfluoroarenes via palladium-catalyzed C-H activation is presented. This transformation proceeds efficiently at moderate reaction temperatures and does not require strong base or reactive intermediates. A near stoichiometric amount of CO is sufficient and the methodology can thus be easily expanded to include the preparation of [(13)C]-acyl labeled benzopolyfluorophenones.

  1. tBuLi-Mediated One-Pot Direct Highly Selective Cross-Coupling of Two Distinct Aryl Bromides

    NARCIS (Netherlands)

    Vila, Carlos; Cembellin, Sara; Hornillos, Valentin; Giannerini, Massimo; Fananas-Mastral, Martin; Feringa, Ben L.

    2015-01-01

    A Pd-catalyzed direct cross-coupling of two distinct aryl bromides mediated by tBuLi is described. The use of [Pd-PEPPSI-IPr] or [Pd-PEPPSI-IPent] as catalyst allows for the efficient one-pot synthesis of unsymmetrical biaryls at room temperature. The key for this selective cross-coupling is the use

  2. FLUORESCENCE SPECTROSCOPIC STUDY OF THE FORMATION OF HYDROPHOBIC MICRODOMAINS IN AQUEOUS-SOLUTIONS OF POLY(ALKYLMETHYLDIALLYLAMMONIUM BROMIDES)

    NARCIS (Netherlands)

    YANG, YJ; ENGBERTS, JBFN

    1991-01-01

    The conformational state of poly(alkylmethyldiallylammonium bromides) was studied in aqueous solutions using pyrene as a fluorescence probe. The results are indicative for the formation of hydrophobic microdomains in the case of several copolymers which possess sufficiently hydrophobic alkyl side ch

  3. Charging of Poly(methyl methacrylate) (PMMA) Colloids in Cyclohexyl Bromide : Locking, Size Dependence, and Particle Mixtures

    NARCIS (Netherlands)

    van der Linden, Marjolein N.; Stiefelhagen, Johan C. P.; Heessels-Gurboga, Gulsen; der Hoeven, Jessi E. S. van; Elbers, Nina A.; Dijkstra, Marjolein; van Blaaderen, Alfons

    2015-01-01

    We studied suspensions of sterically stabilized poly(methyl methacrylate) (PMMA) particles in the solvent cyclohexyl bromide (CHB; epsilon(r) = 7.92). We performed microelectrophoresis measurements on suspensions containing a single particle species and on binary mixtures, using confocal microscopy

  4. Optimisation and validation of a capillary electrophoresis method for the simultaneous determination of diazepam and otilonium bromide.

    Science.gov (United States)

    Furlanetto, S; Orlandini, S; Massolini, G; Faucci, M T; La Porta, E; Pinzauti, S

    2001-10-01

    A simultaneous assay of diazepam and otilonium bromide in coated tablets by capillary zone electrophoresis (CZE) was developed. The influence of various parameters (voltage, temperature, buffer concentration and pH, ethanol percentage) on analysis time and on the theoretical plates of the two peaks was investigated by means of experimental design. A response surface study was carried out by means of a 27-run D-optimal matrix. The best background electrolyte was found to be 0.13 M, pH 2.9 Britton-Robinson buffer, containing 10% v/v ethanol. Other optimised parameters were voltage (30 kV) and temperature (30 degrees C). The UV detector for quantitation of otilonium bromide and diazepam was set at 280 nm and 230 nm, respectively. Procaine hydrochloride was used as internal standard and run time was less than five minutes. Validation was performed, for drug substance and drug product, according to ICH3 guidelines. For drug product the recovery for otilonium bromide and diazepam ranged from 98.3% to 101.2% and from 97.1% to 99.0%, respectively; the RSD values found for otilonium bromide and diazepam ranged from 2.4% to 3.0% and from 1.1% to 4.5%, respectively.

  5. Alternative fumigants to methyl bromide for killing pupae and preventing emergence of apple maggot fly (Diptera:Tephritidae)

    Science.gov (United States)

    Effects of methyl bromide, ECO2FUME (phosphine gas + CO2), Vapam (sodium methyldithiocarbamate), chloropicrin, Telone II (1, 3 dichloropropene), and chloropicrin + Telone II on killing the pupae and preventing adult emergence of apple maggot fly, Rhagoletis pomonella (Walsh) was determined. In an e...

  6. ENTHALPIES OF INTERACTION BETWEEN DIMETHYLDIOCTADECYLAMMONIUM BROMIDE VESICLES IN AQUEOUS-SOLUTION AND EITHER DIPICOLINATE OR SULFATE ANIONS

    NARCIS (Netherlands)

    BLANDAMER, MJ; BRIGGS, B; BUTT, MD; CULLIS, PM; WATERS, M; ENGBERTS, JBFN; HOEKSTRA, D

    1994-01-01

    Injection of small aliquots of dipicolinate anions (sodium salt) into an aqueous solution containing dimethyldioctadecylammonium bromide (DOAB) vesicles is endothermic at 50-degrees-C, becoming first more and then less endothermic. The injection process is effectively athermal for solutions containi

  7. Iodide Impurities in Hexadecyltrimethylammonium Bromide (CTAB) Products: Lot−Lot Variations and Influence on Gold Nanorod Synthesis

    NARCIS (Netherlands)

    Rayavarapu, Raja Gopal; Ungureanu, Constantin; Krystec, Petra; Leeuwen, van Ton G.; Manohar, Srirang

    2010-01-01

    Recent reports [Smith and Korgel Langmuir 2008, 24, 644−649 and Smith et al.Langmuir 2009, 25, 9518−9524] have implicated certain hexadecyltrimethylammonium bromide (CTAB) products with iodide impurities, in the failure of a seed-mediated, silver and surfactant-assisted growth protocol, to produce g

  8. High-Speed Analyzing PCR Products of M. tuberculosis Genome Stained by Ethidium Bromide on Microchip Gel Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    JIN,Qing-Hui(金庆辉); CHEN,Ji-Feng(陈继锋); JING,Feng-Xiang(景奉香); ZHAO,Jian-Long(赵建龙); XU,Yuan-Sen(徐元森)

    2002-01-01

    The technique of microchip gel electrophoresis (MCGE) was used to analyze the polymerase chain reaction (PCR) products of M. tuberculosis Genome stained by ethidium bromide. The electrophoretic process was completed within 3-4 min and the results show that the technique of microchip electrophoresis is a high-speed and high-sensitivity analyzing method.

  9. High—Speed Analyzing PCR Products of M.tuberculosis Genome Stained by Ethidium Bromide on Microchip Gel Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    金庆辉; 陈继锋; 等

    2002-01-01

    The technique of microchip gel electrophoresis(MCGE) was used to analyze the polymerase chain reaction (PCR) products of M.tuberculosis Genome stained by ethidium bromide,The electrophoretic Process was completed within 3-4 min and the results show that the technique of microchip electrophoresis is a high-speed and high-sensitivity analyzing method.

  10. Regioselective Propargylation of Aldehydes with Propargyl Bromide Mediated by Sn-In in Aqueous Media under Microwave Irradiation

    Institute of Scientific and Technical Information of China (English)

    Cheng Zhi GU; Qian Rong LI; Hao YIN

    2005-01-01

    Tin-indium were employed in the propargylations of various aldehydes with propargyl bromide in the presence of SnCl2 and C6 H5(CH3)3NBr under microwave irradiation to afford the corresponding homopropargyl alcohols exclusively in high yields. All the reactions were completed smoothly in predominantly aqueous media in 200 seconds only.

  11. Formation of halogenated organic byproducts during medium-pressure UV and chlorine coexposure of model compounds, NOM and bromide.

    Science.gov (United States)

    Zhao, Quan; Shang, Chii; Zhang, Xiangru; Ding, Guoyu; Yang, Xin

    2011-12-01

    When chlorine is applied before or during UV disinfection of bromide-containing water, interactions between chlorine, bromide and UV light are inevitable. Formation of halogenated organic byproducts was studied during medium-pressure UV (MPUV) and chlorine coexposure of phenol, nitrobenzene and benzoic acid and maleic acid, chosen to represent electron-donating aromatics, electron-withdrawing aromatics, and aliphatic structures in natural organic matter (NOM), respectively. All were evaluated in the presence and absence of bromide. MPUV and chlorine coexposure of phenol produced less total organic halogen (TOX, a collective parameter for halogenated organic byproducts) than chlorination in the dark, and more haloacetic acids instead of halophenols. Increases in TOX were found in the coexposure of nitrobenzene and benzoic acid, but maleic acid was rather inert during coexposure. The presence of bromide increased the formation of brominated TOX but did not significantly affect total TOX formation, in spite of the fact that it reduced hydroxyl radical levels. MPUV and chlorine coexposure of NOM gave a higher differential UV absorbance of NOM and a larger shift to lower molecular weight compounds than chlorination in the dark. However, TOX formation with NOM remained similar to that observed from dark chlorination.

  12. Grafting, metham sodium, soil solarization and virtually impermeable films as alternative technologies to methyl bromide for Chinese protected tomatoes

    Institute of Scientific and Technical Information of China (English)

    Han Xuemei; Cao Zhiping; Chen Yunfeng; Chen Guokang; Andrea Camponogara; Yang Hang; Maria Lodovica Gullino

    2009-01-01

    In the frame of the Sino-ltalian Cooperation Program for Environmental Protection,jointly launched in the year 2000 by the Italian Ministry for Environment and Territory and Sea (IMETS) and the China State Environ nental Protection Administration (SEPA),experimental trials were carried out in Qingzhou city (Shandong Prov ince,China) during 2001-2003 to test several methyl bromide alternative methods to control soilborne diseases in greenhouse tomatoes.Grafting tomatoes on resistant rootstock (Lycopersicon lycopersicum×L.hirsutum),metham sodium applied under traditional polyethylene ptastic films,metham sodium applied at low rate under virtually im permeable films and soil solarization combined with biocontrol agents were the alternatives tested and compared to methyl bromide applied under virtually impermeable plastic films too.Collected data show that resistant rootstock (Lycopersicon lycopersicum × L.hirsutum) introduced from Italy is a promising alternative to methyl bromide for to cal tomato cultivars.Metham sodium applied under traditional polyethylene plastic films is an effective alternative Moreover,virtually impermeable.films demonstrate the help to reduce methyl bromide and metham sodium rates.Finally,soil solarization combined with biocontrol agents does not provide satisfactory resuhs in terms of disease control.

  13. Impact of bromide on halogen incorporation into organic moieties in chlorinated drinking water treatment and distribution systems.

    Science.gov (United States)

    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.

  14. Microstructure and dielectric properties of dysprosium-doped barium titanate ceramics Microestrutura e propriedades dielétricas de cerâmicas de titanato de bário dopado com disprósio

    Directory of Open Access Journals (Sweden)

    Y. Pu

    2005-09-01

    Full Text Available The substitution behavior and lattice parameter of barium titanate between solid_solubility with a dopant concentration in the range of 0.25 to 1.5 mol% are studied. The influences of dysprosium-doped fraction on the grain size and dielectric properties of barium titanate ceramic, including dielectric constant and breakdown electric field strength, are investigated via scanning electronic microscopy, X-ray diffraction and electric property tester. The results show that, at a dysprosium concentration of 0.75 mol%, the abnormal grain growth is inhibited and the lattice parameters of grain rise up to the maximum because of the lowest vacancy concentration. In addition, the finegrain and high density of barium titanate ceramic result in its excellent dielectric properties. The relative dielectric constant (25 °C reaches to 4100. The temperature coefficient of the capacitance varies from -10 to 10% within the temperature range of -15 °C -100 °C, and the breakdown electric field strength (alternating current achieves 3.2 kV/mm. These data suggest that our barium titanate could be used in the manufacture of high voltage ceramic capacitors.Foram estudados o comportamento da substituição e o parâmetro de rede de titanato de bário da solubilidade sólida com uma concentração de dopante na faixa 0,25-1,5 mol%. As influências da fração do dopante disprósio no tamanho de grão e nas propriedades dielétricas da cerâmica de titanato de bário, incluindo constante dielétrica e rigidez dielétrica foram investigadas por meio de microscopia eletrônica de varredura, difração de raios X e teste de propriedades elétricas. Os resultados mostram que a uma concentração de disprósio de 0,75 mol% o crescimento anormal de grão é inibido e os parâmetros de rede aumentam até um máximo devido a menor concentração de vacâncias. Além disso, as cerâmicas de grãos pequenos e alta densidade resultam em excelentes propriedades dielétricas. A

  15. Neodymium Dysprosium Modified Starch- coated Magnetic Fluid Preparation of Ferrite%淀粉包覆镝钕改性铁氧体磁性液体的制备

    Institute of Scientific and Technical Information of China (English)

    林穗云; 周育辉

    2011-01-01

    In this paper, in order to obtain the ferrite magnetic fluids of higher saturation magnetic intensity with simple technology, nanometer magnetite ( Fe3O4 ) particles ware prepared by chemical co - precipitation. And to a certain proportion of Dysprosium Neodymium ferrite magnetic fluids on the modification, we selected starch prepara- tion for the relief of water - based coating of rare earth iron oxide magnetic fluid composites. We also investigated the amount of Nd - Dy, the amount of coating agent, reaction temperature, coating temperature on the performance of the products and the effects of particle size, and its preliminary characterization was also performed . Through experiment,we summed up, under n (Fe) : [ n ( Nd3+ ) + n ( Dy3+ ) ] = 30:1 and n ( Fe3 + ) : n ( Fe2 + ) = 1.70 ~ 1. 75, the ratio for use of dysprosium and neodymium is n(Dy3+ ) : n(Nd3+ ) =4:1, 25%NH3 · H2O(A. R. ) as precipitating agent and pH value conditioner; the reacting system temperature was controlled in 35 ℃, and the pH value was adjusted to 9 ~ 11 ; the best dosage of starch as the relief is O. 0050g each 6OraL magnetic fluids, the temperature of surfactant was controlled in 50℃ and the pH value was adjusted to 2 ~ 3. In such system under the conditions of a water - based rare - earth compound Nd Dy Fe Magnetic, fluid magnetic oxygen was higher than or- dinary water- based ferrite.%为制备工艺简单且饱和磁化强度高的磁流体,本文采用化学共沉淀法制得了纳米磁性Fe304粒子.然后以一定比例的镝钕对铁氧体磁流体改性,选择淀粉为包覆剂制备水基稀土复合铁氧磁流体.考察了镝钕的用量、包覆剂的用量、反应温度、包覆温度等因素对产物粒径及性能的影响,并对其进行了初步的性能表征.实验总结出适宜的条件:在n(Fe):[n(Nd3+)+n(Dy3+)]=30:1,n(Fe3+):n(Fe2+)=1.70~1.75

  16. Reasoned opinion on the review of the existing maximum residue levels (MRLs for methyl bromide according to Article 12 of Regulation (EC No 396/2005

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2013-07-01

    Full Text Available According to Article 12 of Regulation (EC No 396/2005, the European Food Safety Authority (EFSA has reviewed the Maximum Residue Levels (MRLs currently established at European level for the pesticide active substance methyl bromide. Although this active substance is no longer authorised within the European Union, guideline levels for methyl bromide (at point of retail sale or when offered for consumption and MRLs for bromide ion, which is a relevant metabolite of methyl bromide, were established by the Codex Alimentarius Commission (CXLs. Regarding methyl bromide, the default MRL of 0.01 mg/kg as defined by Regulation (EC No 396/2005 is compliant with the Codex guideline levels and provides a satisfactory level of protection for the European consumer but it could not be demonstrated that the default MRL can be achieved in routine enforcement. Moreover, based on the assessment of the available data, some CXLs were found not to be adequately supported by data and the consumer risk assessment could not be finalised, as the toxicological reference values of bromide ion need to be revised and only few information on the natural occurrence of bromide ion in food was available to EFSA. Hence, further consideration by risk managers is needed.

  17. HYOSCINE BUTYL BROMIDE VERSUS DROTAVERINE HYDROCHLORIDE IN ACTIVE STAGE OF LABOUR-A COMPARATIVE STUDY OF RATE OF CERVICAL DILATATION

    Directory of Open Access Journals (Sweden)

    Misha Pepsi

    2014-05-01

    Full Text Available AIM: This study was conducted to compare the rate of cervical dilatation with hyoscine butyl bromide and drotaverine hydrochloride in active stage of labour. MATERIALS AND METHODOLOGY: This prospective study was conducted in the department of Obstetrics and Gynaecology. Inclusion Criteria: 1. All women with initial cervical dilatation of 3 cms. 2. When there is a slow rate of cervical dilatation of less than 1.5 cms per hour or decent of less than 1 cm per hour for nulliparous and if dilatation was less than 2cms per hour for a multigravida. 3. And all singleton and cephalic pregnancies were included in this study. Exclusion Criteria included complications like Antepartum haemorrhage, Breech, C.P.D. In this study 400 women were allocated into two groups to receive either Hyoscine butyl bromide or Drotaverine hydrochloride. Two hours after admission in the active stage of labour, progress of labour was reassessed. If the progress of labour was satisfactory, then the wait and watch policy was adopted. If there was no progress they were administered one of the two drugs. 200 patients were administered 10mg of hyoscine butyl bromide suppositories rectally, (GROUP-1 AND THE OTHER 200 WITH 40mg of drotaverine hydrochloride intravenously (GROUP-2. The progress of labour was monitored by the partogram. Not more than 3 doses of hyoscine butyl bromide were administered. RESULTS: The rate of cervical dilatation was 2 cms per hour in group 1 (Hyoscine butyl bromide as compared to 1cm per hour in group 2 (Drotaverine hydrochloride. The difference in rate of cervical dilatation in both the groups was statistically significant. CONCLUSION: There was significant improvement in the rate of cervical dilatation with Hyoscine butyl bromide group of patients. There was a significant reduction in the duration of active stage of labour, and there was no significant second and third stage complication when these drugs were used. No untoward side effects were noted when

  18. Estudo da adsorção de brometo de etídeo em resina XAD-7 Study of ethidium bromide adsorption on XAD-7 resin

    Directory of Open Access Journals (Sweden)

    Mônica Winkler de Oliveira

    2009-01-01

    Full Text Available The adsorption of ethidium bromide on XAD-7 resin was studied. The Freundlich model was the most representative isotherm model to describe the sorption behavior. A solid-liquid equilibrium model was proposed to explain the resin mass influence on the sorption. The equilibrium constant value estimated was 2.31. The results showed an ethidium bromide ion-pair physical adsorption, with adsorption enthalpy equals to -19.33 kJ/mol. A pK2 value equals to 4.69 ± 0.01 was estimated by two distinct methods. The results will be applied to the ethidium bromide preconcentration aiming its decomposition.

  19. Pressure Effects on Structure and Optical Properties in Cesium Lead Bromide Perovskite Nanocrystals.

    Science.gov (United States)

    Xiao, Guanjun; Cao, Ye; Qi, Guangyu; Wang, Lingrui; Liu, Chuang; Ma, Zhiwei; Yang, Xinyi; Sui, Yongming; Zheng, Weitao; Zou, Bo

    2017-07-26

    Metal halide perovskites (MHPs) are gaining increasing interest because of their extraordinary performance in optoelectronic devices and solar cells. However, developing an effective strategy for achieving the band-gap engineering of MHPs that will satisfy the practical applications remains a great challenge. In this study, high pressure is introduced to tailor the optical and structural properties of MHP-based cesium lead bromide nanocrystals (CsPbBr3 NCs), which exhibit excellent thermodynamic stability. Both the pressure-dependent steady-state photoluminescence and absorption spectra experience a stark discontinuity at ∼1.2 GPa, where an isostructural phase transformation regarding the Pbnm space group occurs. The physical origin points to the repulsive force impact due to the overlap between the valence electron charge clouds of neighboring layers. Simultaneous band-gap narrowing and carrier-lifetime prolongation of CsPbBr3 trihalide perovskite NCs were also achieved as expected, which facilitates the broader solar spectrum absorption for photovoltaic applications. Note that the values of the phase change interval and band-gap red-shift of CsPbBr3 nanowires are between those for CsPbBr3 nanocubes and the corresponding bulk counterparts, which results from the unique geometrical morphology effect. First-principles calculations unravel that the band-gap engineering is governed by orbital interactions within the inorganic Pb-Br frame through structural modification. Changes of band structures are attributed to the synergistic effect of pressure-induced modulations of the Br-Pb bond length and Pb-Br-Pb bond angle for the PbBr6 octahedral framework. Furthermore, the significant distortion of the lead-bromide octahedron to accommodate the Jahn-Teller effect at much higher pressure would eventually lead to a direct to indirect band-gap electronic transition. This study enables high pressure as a robust tool to control the structure and band gap of CsPbBr3 NCs, thus

  20. Transport of Alachlor, Atrazine, Dicamba, and Bromide through Silt and Loam Soils

    Science.gov (United States)

    Tindall, J. A.

    2015-12-01

    The herbicides alachlor, atrazine, and dicamba, as well as bromide were applied to soils overlying the High Plains aquifer in Nebraska, to both macropore and non-macropore sites. Three of 6 study areas (exhibiting a high percentage of macropores) were used for analysis of chemical transport. Twelve intact soil cores (30 cm diameter; 40 cm height), were excavated (two each from 0-40 cm and 40-80 cm depths). The first three study areas and soil cores were used to study preferential flow characteristics using dye staining and to determine hydraulic properties; the remaining cores were treated the same as field macropore sites. Two undisturbed experimental field plots, each with a 1 m2 surface area, were established in each of the three macropore study areas. Each preferential plot was instrumented with suction lysimeters, tensiometers, and neutron access tubes - 10 cm increments to 80 cm - and planted in corn. Three study areas that did not exhibit macropores had alachlor, atrazine, and dicamba and bromide disked into the top 15 cm of soil; concentrations were tracked for 120 days - samples were collected on a grid, distributed within 3 plots measuring 50 m x 50 m each. Core samples were collected prior to and immediately after application, and then at 30, 60, and 120 days after application. Each lab core sample was in 15-cm lengths from 0-15 cm, 15-30 cm, 45-60 cm, and 75-90 cm. For areas exhibiting macropores, herbicides had begun to move between 10-15 days after application with concentrations peaking at various depths after heavy rainfall events. Field lysimeter samples showed increases in concentrations of herbicides at depths where laboratory data indicated greater percentages of preferential flowpaths. Concentrations of atrazine, alachlor and dicamba exceeding 0.30, 0.30, and 0.05 μg m1-1 respectively were observed with depth (10-30 cm and 50-70 cm) after two months following heavy rainfall events indicating that preferential flowpaths were a significant