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Summary Lattice parameter values were determined for the ternary B 2-phase in the Al-Co-Ga system, and it was found that a continuous solid solution exists between -AlCo and -CoGa. Phase boundaries of the ternary phase at 1 100 K were derived from the variation of the lattice parameter with composition.
Über die ternäre B 2-Phase im System Al-Co-Ga
Zusammenfassung Im Bereich der ternären B 2-Phase im System Al-Co-Ga wurden die Werte des Gitterparameters bestimmt; es stellte sich heraus, daß eine durchgehende feste Lösung zwischen -AlCo und -CoGa besteht. Die Phasengrenzen der ternären Phase bei 1 100 K wurden aus der Änderung des Gitterparameters mit der Zusammensetzung abgeleitet.相似文献
4.
Adolf Slawisch 《无机化学与普通化学杂志》1970,374(3):291-296
The reaction of VOCl3 with sily-substituted amines results in the substitution of oxygen in VOCl3 and in compounds of type Cl3V = NR. In this way, we succeeded in isolating the pure compound Cl3V = NCH3 (I). The existence of compound (Cl3VNC6H5)x (II) was proved by direct synthesis from Cl3VO and ((CH3)3Si)2NC6H5, and by the decomposition of the new addition compounds Cl3VO · 2 OCNC6H5 (III) and Cl3VO · 2 OSNC6H5 (IV). 相似文献
5.
By means of EMF-measurements using the formation cell $$graphite/Ag/AgCl(l,x_{AgCl} ) - LiCl(l,x_{LiCl} ) - KCl x_{KCl} /(Cl_2 )graphite$$ the partial molar excessGibbs energies,G AgCl E , of silver chloride in the ternary system AgCl?LiCl?KCl were determined over the whole concentration range at five temperatures between 973 K and 1,123 K. The experimentally determinedG AgCl E -values were fitted using theRedlich-Kister equation. From theRedlich-Kister parameters and their temperature dependence, obtained by the fitting procedure, the integral and partial molar excessGibbs energies, heats of mixing, and excess entropies were calculated. The fitting process permits also the calculation of the thermodynamic excess function of the binary system lithium chloride—potassium chloride. 相似文献
6.
Prof. Dr. Hans Nowotny Josef Tomiska László Erdélyi Adolf Neckel 《Monatshefte für Chemie / Chemical Monthly》1977,108(1):7-19
By means of vapor pressure measurements using theTorker method (Torsion-Knudsen Effusion Recoil) as well as theKnudsen tanspiration technique in connection with a mass spectrometer, the heats of formation of the following compounds were found to be –6.5±0.7 kcal/g atom (Mn0.366Si0.634), –7.8±0.6 kcal/g atom (Mn0.50Si0.50), –7.3±0.6 kcal/g atom (Mn0.625Si0.375), and –6.6±0.6 kcal/g atom (Mn0.75Si0.25).
Mit 7 Abbildungen 相似文献
Mit 7 Abbildungen 相似文献
7.
Stefan Müllegger Kathrin H?nel Thomas Strunskus Christof W?ll Adolf Winkler 《Chemphyschem》2006,7(12):2552-2558
Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy has been applied to reveal the molecular arrangement of ultrathin oligophenyl films [p-quaterphenyl (4P) and p-hexaphenyl (6P)] on Au(111). In the half-monolayer films the molecules lie flat on the surface but still have a considerable inter-ring twist of 30 degrees -40 degrees , similar to the gas-phase conformation. In the saturated monolayer film the second half of the molecules is side-tilted by an angle of less than 66 degrees with respect to the surface. This arrangement is already similar to that in bulk net planes of thicker films parallel to the surface, that is, the 4P(211) and 6P(21-3) planes, respectively. 相似文献
8.
Preparation of Stilbenyl Derivatives of Isoxazoles Schiff's bases derived from 3- and 5-(p-formylphenyl)-phenylisoxazoles and o- or p-chloroaniline are reacted with various p-tolyl substituted aromatic heterocycles in the presence of dimethylformamide and potassium hydroxide or potassium t-but-oxide to yield the corresponding heterocyclic substituted stilbenes (‘Anil synthesis’). 5-[4-(Chlorphenylimino-methyl)phenyl]-phenylisoxazoles react less readily than the corresponding 3-isomers. 相似文献
9.
Wolfgang A. Herrmann Martina Flöel Cornelia Weber John L. Hubbard Adolf Schäfer 《Journal of organometallic chemistry》1985,286(3):369-397
The eighteen new μ-alkylidene ruthenium complexes 5a–r and 5t are very easily and cleanly obtained along the diazoalkane or the hydrazone routes that involve treatment of the dinuclear, metal-metal doubly bonded precursor compound [(η5-C5H5)Ru(μ-NO)]2 (3) either with the diazoalkanes oxidizing agent (e.g., MnO2), with the respective hydrazones. Similarly, sulfur dioxide adds cleanly to the RuRu double bond of 3, thus giving the complex (μ-SO2)[(η5-C5H5)Ru(NO)]2 (5s). Regardless of the nature of the carbene bridge ligands, the dimetallacyclopropanes exhibit, in contrast to their iron analogues, exclusively terminal nitrosyl ligands. cis/trans-Isomerism with predominating amounts of the trans-isomers is observed for the derivatives that display unsymmetrically substituted carbene bridges.Treatment of the μ-methylene- and μ-ethylidene complexes (μ-CH2)[(η5-C5H5)Ru(NO)]2 (5a) and (μ-CHCH3)[(η5-C tetrafluoroboric acid or trifluoromethanesulfonic acid in diethyl ether yields, at ambient temperature, quantitatively the ionic complexes 6a,b and 7a,b, respectively, which were shown by 1H NMR spectroscopy to contain metal-metal bridging hydrogen functionalities. The reaction of hydrogen bromide with 5a under the same conditions gives the neutral bromo(methyl) complex 6d. This latter compound results from the isolable ionic intermediate of composition [(μ-CH2)(μ-H){(η5C5H5)Ru(NO)}2]+Br? (6c), which reaction stems from the nucleophilicity of the halide ion present in 6c. 相似文献
10.
Wilfried A. Knig Detlef Icheln Torsten Runge Ingo Pforr Adolf Krebs 《Journal of separation science》1990,13(10):702-707
Transferring the site of specific substitution of dipentylated cyclodextrins with methyl or acyl residues from the secondary 3-hydroxyl group to the primary 6-hydroxyl group was expected to provide new information on the mechanism of chiral recognition. The 3-position points towards and the 6-position points away from the cyclodextrin cavity which via inclusion complex formation is supposed to play a major role in chiral separation. The “inverse” 6-O-acyl-2,3-di-O-pentyl-cyclodextrins displayed almost no enantioselectivity but the corresponding 6-O-methyl derivatives are a versatile supplement to the chiral capillary GC phases nowadays available. Among the compounds that could be enantiomerically resolved are alcohols, amino acids, alkyl halides, bicyclic ethers, acetals, olefins, other hydrocarbons and chiral pharmaceuticals. 相似文献