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101.
Vukadin M. Leovac Goran A. Bogdanović Valerija I. Češljević Ljiljana S. Jovanović Sladjana B. Novaković Ljiljana S. Vojinović-Ješić 《Structural chemistry》2007,18(1):113-119
The ligand, salicylaldehyde Girard-T hydrazonium chloride, [H2SalGT]Cl (1), and two complexes [Cu(HSalGT)X2]·H2O (X = Br(2); Cl(3)) were synthesized and their crystal structures were determined by single-crystal X-ray analysis. In the two isostructural
complexes, the Cu(II) is located in a square-pyramidal environment, with the chelating ligand and one halogen atom in the
basal plane and the second halogen in the apical position. The most apparent structural difference between the 1 and its complexes 2 and 3 is the orientation of the N(CH3)3 group: in 1, it is practically coplanar to the rest of the molecule, while in 2 and 3 it is oriented to the side of the axially bonded halogen, which can be explained by the C–H…X intramolecular interactions.
The compounds were characterized by elemental analysis, molar conductivity, magnetic susceptibility and electronic absorption
spectra. 相似文献
102.
R. C. Heaton W. A. Taylor D. R. Phillips Sr. D. J. Jamriska J. B. Garcia 《Journal of Radioanalytical and Nuclear Chemistry》1995,195(2):271-277
Zinc oxide targets irradiated with high energy protons at the Los Alamos Meson Physics Facility (LAMPF) contain a number of radioactive spallation products in quantities large enough to warrant recovery. This paper describes methods for recovering7Be,46Sc, and48V from such targets and offers suggestions on possible ways to recover additional isotopes. The proposed methods are based on traditional precipitation and ion exchange techniques, are readily adaptable to hot cell use, and produce no hazardous waste components. The products are obtained in moderate to high yields and have excellent radionuclidic purity. 相似文献
103.
The redox properties of the system Fe(tmphen)3(II/III) (tmphen=3,4,7,8-tetramethyl-1,10-phenanthroline) have been studied in the solvents nitromethane, acetonitrile, propanediol-1,2-carbonate, dimethylformamide, dimethylacetamide, dimethylsulfoxide and of the systems Fe(phen)3(II/III) (phen=1,10-phenanthroline) and Fe(niphen)3(II/III) (niphen=5-nitro-1,10-phenanthroline) in the solvents nitromethane, acetonitrile, propanediol-1,2-carbonate and acetone. The redox potentials of Fe(tmphen)3(II/III) are nearly independent of the solvent suggesting that the system might be used as a reference redox couple similar to the systems ferrocene/ferricinium or bisbiphenylchromium(0/I). In contrast the redox potentials of Fe(niphen)3(II/III) show a significant decrease with increasing donor number of the solvent which can be explained by nucleophilic attack of solvent molecules at the iron. It is shown that such a mechanism is consistent with the known solvent and salt effects on the kinetics of dissociation of ferroin and ferriin type complexes. 相似文献
104.
Ohne Zusammenfassung 相似文献
105.
106.
Kučinskaitė Agnė Pobłocka-Olech Loretta Krauze-Baranowska Mirosława Briedis Vitalis Savickas Aruñas Sznitowska Małgorzata 《平面色谱法杂志一现代薄层色谱法》2007,20(2):121-125
SPE and TLC have been used for qualitative and quantitative analysis of salidroside, rosavin, rosarin, and rosin in commercially available dry extracts from Rhodiola rosea roots. The best separation of all the compounds was achieved on silica gel TLC plates with ethyl acetate—methanol—water, 77 + 13 + 10 (v/v), as mobile phase. UV detection was performed at λ = 215 nm for salidroside and at λ= 245 nm for the rosavins (rosavin, rosarin, and rosin). Detection limits for salidroside and the rosavins were 90 ng and 60 ng per spot, respectively. Results from quantitative analysis confirmed the manufacturer’s declaration of the amounts of salidroside and the rosavins in the extracts.
相似文献107.
Ohne Zusammenfassung 相似文献
108.
The phase analysis of cryolite (Na3AlF6) and sodium metasilicate (Na2SiO3) was performed by thermal analysis. The eutectic system with a region of two immiscible substances at a concentration of Na2SiO3 between 42.8 and 46.3 mol‐% was identified and the eutectic temperature determined to (886±2) °C. Based on the results of mass‐loss measurements, it was assumed that the introduced Na2SiO3 reacts with Na3AlF6 due to the formation of some nonvolatile stable compounds. The stable reaction products were identified by X‐ray diffraction analysis and IR spectroscopy of the spontaneously cooled samples, which established the formation of NaF and stable amorphous aluminosilicate compounds. 相似文献
109.
D. Reichardt V. Bonačić-Koutecký P. Fantucci J. Jellinek 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):486-489
An ab-initio molecular dynamics procedure without precalculation of the Born-Oppenheimer energy surface based on an iterative non-local density functional method employing Gaussian atomic basis has been developed. Analytical gradients are calculated and used for the propagation of nuclei. Sufficiently long trajectories can be calculated at an acceptable computational cost, allowing for analysis of dynamical behaviour of small metallic clusters. This is illustrated on an example of the Li8 cluster. Temperature behaviour of different type of isomers has been investigated. Calculated power spectra allow to identify the presence of more than one isomeric forms along the given trajectories. 相似文献
110.
Laila Čakare Marija Kosec Barbara Malič 《Journal of Sol-Gel Science and Technology》2000,19(1-3):603-606
PbZrO3 (PZ) thin films have been prepared by 2-methoxyethanol route from lead oxide or lead acetate and zirconium n-butoxide. The use of lead oxide as lead source and the seeding layer of TiO2 on Pt/TiO2/SiO2/Si substrate facilitate the formation of the perovskite phase. 相似文献