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Barium Acetate (barium + acetate)
Selected AbstractsPlasma free fatty acid profiling in a fish oil human intervention study using ultra-performance liquid chromatography/electrospray ionization tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 13 2008Nicole Zehethofer A rapid method was developed for the simultaneous profiling of 29 free fatty acids in plasma using ultra-performance liquid chromatography/electrospray ionization tandem mass spectrometry (UPLC/ESI-MS/MS). Barium acetate was used as the cationization agent in the positive ion mode for sensitive multiple reaction monitoring (MRM) experiments. The cis- and trans -C18:1 and -C18:2 isomers were baseline-separated using two tandem reversed-phase C18 UPLC columns, while identification of two pairs of positional isomers of C18:3 and C20:3 required isomer-specific product ions, as the analytes were not chromatographically resolved. The assay linearity was greater than three orders of magnitude and correlation coefficients were >0.99; the limits of detections were typically less than 0.2,µM. The method was successfully applied to plasma free fatty acid profiling of samples from volunteers who participated in a randomized crossover study involving the administration of either placebo or fish oil capsules. The results clearly indicate the ability to measure the time profiles of the n -3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in plasma for the volunteers given fish oil capsules while the concentrations of the other free fatty acids and the total free fatty acid concentration in plasma remained virtually constant. Copyright © 2008 John Wiley & Sons, Ltd. [source] Spray Pyrolysis of Fe3O4,BaTiO3 Composite ParticlesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2009Tomoyuki Adachi Fe3O4,BaTiO3 composite particles were successfully prepared by ultrasonic spray pyrolysis. A mixture of iron(III) nitrate, barium acetate and titanium tetrachloride aqueous solution were atomized into the mist, and the mist was dried and pyrolyzed in N2 (90%) and H2 (10%) atmosphere. Fe3O4,BaTiO3 composite particle was obtained between 900° and 950°C while the coexistence of FeO was detected at 1000°C. Transmission electron microscope observation revealed that the composite particle is consisted of nanocrystalline having primary particle size of 35 nm. Lattice parameter of the Fe3O4,BaTiO3 nanocomposite particle was 0.8404 nm that is larger than that of pure Fe3O4. Coercivity of the nanocomposite particle (390 Oe) was much larger than that of pure Fe3O4 (140 Oe). These results suggest that slight diffusion of Ba into Fe3O4 occurred. [source] Low-Temperature Synthesis of Fully Crystallized Spherical BaTiO3 Particles by the Gel,Sol MethodJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2004Un-Yeon Hwang The synthesis of spherical BaTiO3 particles was attempted by a new technique, the "gel,sol method," at 45°C. The (Ba,Ti) gel used as a starting material was prepared by aging mixtures of titanyl acylate with a barium acetate aqueous solution ([glacial acetic acid (AcOH)]/[titanium isopropoxide (TIP)] = 4, [barium acetate]/[TIP] = 1) at 45°C for 48 h. Potassium hydroxide (KOH) was used as a catalyst for the formation of BaTiO3. Powder X-ray diffractometry (XRD) results and Fourier-transform infrared (FT-IR) measurements for the (Ba,Ti) gel showed that the gel was amorphous, but the spatial arrangement of barium and titanium in the (Ba,Ti) gel is similar to that in crystalline BaTiO3 particles. Fully crystallized spherical BaTiO3 powder with a particle size of 40,250 nm formed at the very low reaction temperature of 45°C. Scanning electron microscopy images showed that the final particles formed via aggregation of the fine particles that seem to be the primary particles of bulk (Ba,Ti) gel. From the XRD, FT-IR, and Raman spectroscopy analysis, it was found that the crystal structure of the as-prepared particles continuously transformed from cubic to tetragonal as the calcination temperature increased, and high crystalline tetragonal BaTiO3 phase was obtained at 1000°C after 1 h of heat treatment. [source] [Ba6(C2H3O2)12(H2O)3.5], a new hydrate of barium acetateACTA CRYSTALLOGRAPHICA SECTION C, Issue 11 2007Gabriela Leyva A new barium acetate phase, di-,5 -acetato-tri-,4 -acetato-tri-,3 -acetato-tri-,2 -acetato-,2 -acetato-triaquahemiaquahexabarium(II), of analytical formula [Ba6(C2H3O2)12(H2O)3.5], is described. The asymmetric unit contains six independent Ba centres with coordination numbers varying from 7 to 10 arising from bonding to 12 crystallographically independent acetate ligands and four molecules of water, one of which is disordered over two sites both of occupancy 0.5. Bonding to the acetate ligands creates a completely connected three-dimensional structure. All H atoms of the water molecules participate in hydrogen bonding. [source] | ||||||||||