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Barium Chloride (barium + chloride)
Selected AbstractsHydrothermal Synthesis of Tetragonal Barium Titanate from Barium Chloride and Titanium Tetrachloride under Moderate ConditionsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2002Huarui Xu Tetragonal BaTiO3powders were prepared hydrothermally at 240°C, in only 12 h, using BaCl2·2H2O and TiCl4, which are rather easy to manipulate. Characterization via X-ray diffractometry, scanning electron microscopy, Brunauer,Emmett,Teller analysis, and differential scanning calorimetry confirmed that increasing the NaOH excess concentration (from 0.5M to 2.0M) and decreasing the initial TiCl4concentration (from 0.625M to 0.15M) promotes the formation of tetragonal BaTiO3powders. After reaction, the powders were proved to be phase-pure BaTiO3, with no impurities, such as Cl, and CO32,. [source] Analysis of Simulated Martian Regolith Using an Array of Ion Selective ElectrodesELECTROANALYSIS, Issue 15-16 2005Stefan Abstract A prototype miniature array of polymer membrane and solid state ion selective electrodes was developed for the purpose of performing an in-situ analysis of the soluble ionic species in Martian regolith (soil). The array contains a total of 27 electrodes for K+, Na+, Ca2+, Mg2+, NH, Ba2+, NO, Cl,, and Li+, each in triplicate. Barium electrodes were used to indirectly monitor sulfate through precipitation by the addition of barium chloride while the lithium electrodes served as a reference for the array by having a constant lithium concentration as a background for all solutions. The array was tested with several types of simulants, soils, and sawdust from a Mars meteorite, all with varying salt content, meant to approximate the various hypotheses regarding the ionic composition of the Martian soil. The activities of anions and cations determined with the array were compared to ion chromatography data. [source] Transgenerational marking of marine fish larvae: stable-isotope retention, physiological effects and health issuesJOURNAL OF FISH BIOLOGY, Issue 4 2009D. H. Williamson This study examined the toxicological and physiological responses of a commercially important coral-reef grouper, Plectropomus leopardus (Serranidae), to injection of enriched stable-isotope barium chloride (BaCl2) solution. Thirty adult P. leopardus were subject to one of two 138BaCl2 injection treatment groups (corresponding to dosage rates of 2 and 4 mg 138Ba kg,1 body mass), and a control group in which fish were injected with 0·9% sodium chloride (NaCl) solution. Fish from each group were sampled at post-injection intervals of 48 h and 1, 3, 5 and 8 weeks, at which time blood and tissue samples were removed from each fish. Residual concentrations of Ba and 138Ba:137Ba ratios were measured in muscle, gonad, liver and bone tissues of each experimental fish. Elevated Ba concentrations were detected in all treatment fish tissue samples within 48 h post injection. Residual Ba concentrations decreased throughout the remainder of the 8 week experimental period in all tissues except bone. The BaCl2 injection had no significant effects on measured whole blood variables or on the plasma concentrations of steroid hormones. Enriched Ba stable isotopes can therefore be used at low dosages to mark larvae of commercially important marine fishes, without adverse effects on the health of the fishes or on humans who may consume them. [source] Europium-doped barium halide X-ray scintillatorsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3 2007J. Selling Abstract Single crystals of europium-doped barium chloride, bromide, and iodide were investigated under x-ray and ,-ray excitation. The Eu2+ -related x-ray excited luminescence is at 402, 404, and 425 nm for the chloride, bromide, and iodide, respectively. BaCl2:Eu2+ has the most promising scintillation properties of the systems investigated. The light yield is about 20,000 ± 2,000 photons per MeV of absorbed ,-ray energy, the energy resolution for the 662 keV photopeak is 9% ± 1%, and the scintillation decay time is (390 ± 40) ns. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Hydrogen bonding and structure of Ba2Ru2Cl10O·10H2OACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2007Sihem Boufas Dibarium ,-oxido-bis[pentachloridoruthenate(IV)] decahydrate, Ba2Ru2Cl10O·10H2O, has been prepared from ruthenium(III) chloride and barium chloride in hydrochloric acid. It crystallizes in the monoclinic system (space group C2/c). The structure consists of alternating layers of [Ru2Cl10O]4, and [Ba(H2O)7]2+ complex ions along the a direction. The O atom bonded to ruthenium occupies the 4e site, with symmetry, while the other atoms occupy general 8f sites. The overall structure is held together by O,H...O hydrogen bonds and O,H...Cl dipole,dipole interactions. [source] Using barium ions for heavy-atom derivatization and phasing of xylanase II from Trichoderma longibrachiatumACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2007Natalia Moiseeva This paper describes the use of barium chloride to produce a heavy-atom derivative of xylanase II crystals from Trichoderma longibrachiatum, which was obtained either by cocrystallization or soaking. SAD phasing led to interpretable electron-density maps that allowed unambiguous chain tracing. In the best case, with a data set collected at 9.5,keV, 88% of the residues were built, with 83% of the side chains assigned. The barium ions are found to mainly interact with main-chain carbonyl groups and water molecules. It is suggested that barium ions could also be used as a potential anomalous scatterer in the quick cryosoaking procedure for phasing. [source] Overexpression, purification, crystallization and preliminary structural studies of p -coumaric acid decarboxylase from Lactobacillus plantarumACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 4 2007Blanca De Las Rivas The substrate-inducible p -coumaric acid decarboxylase (PDC) from Lactobacillus plantarum has been overexpressed in Escherichia coli, purified and confirmed to possess decarboxylase activity. The recombinant His6 -tagged enzyme was crystallized using the hanging-drop vapour-diffusion method from a solution containing 20%(w/v) PEG 4000, 12%(w/v) 2-propanol, 0.2,M sodium acetate, 0.1,M Tris,HCl pH 8.0 with 0.1,M barium chloride as an additive. Diffraction data were collected in-house to 2.04,Å resolution. Crystals belonged to the tetragonal space group P43, with unit-cell parameters a = b = 43.15, c = 231.86,Å. The estimated Matthews coefficient was 2.36,Å3,Da,1, corresponding to 48% solvent content, which is consistent with the presence of two protein molecules in the asymmetric unit. The structure of PDC has been determined by the molecular-replacement method. Currently, the structure of PDC complexed with substrate analogues is in progress, with the aim of elucidating the structural basis of the catalytic mechanism. [source] | ||||||||||