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861.
G. M. Mamardashvili R. S. Kumeev N. Zh. Mamardashvili 《Russian Journal of Inorganic Chemistry》2006,51(8):1264-1269
The formation of host-guest complexes between dimeric cyclophane zinc diphenylporphyrinates and bidentate ligands of different nature containing two nitrogen atoms has been studied by the spectrophotometric titration method and 1H NMR spectroscopy in a toluene-methanol (2: 1) binary solvent. The complexation of these dimeric porphyrinates with 1,4-diazabicyclo[2,2,2]octane or pyrazine can lead to 1: 1 or 1: 2 complexes, depending on the metalloporphyrin-to-ligand molar ratio. The stability constants of the porphyrinate-ligand complexes and concentration ranges of their formation have been determined. 相似文献
862.
863.
864.
S. Ebel B. Reyer und A. Werner-Busse 《Fresenius' Journal of Analytical Chemistry》1987,327(2):193-197
Summary This paper describes a reliable working station for the in line-process control in chemical plants. Essential parts of the equipment (pump, column) are in duplicates and may be combined by computer control in different lines. One pump and column is in working position, the other is held in ready to work position by conditioning. While one column is in working position, the system is able to calibrate the other column and to switch to this column in the case of breakdown of the other column. By means of chromatographic data (as retention time, peak height of standards, data of separation) the working column is under control and the switching to the other column is down before a real breakdown. The status of the detector is followed by number and distance in time of the necessary auto-zero operations and by the noise of the lamp.
Herrn Prof. Dr. W. Fresenius aus Anlaß des 125jährigen Erscheinens der Fresenius Zeitschrift für Analytische Chemie gewidmet 相似文献
Herrn Prof. Dr. W. Fresenius aus Anlaß des 125jährigen Erscheinens der Fresenius Zeitschrift für Analytische Chemie gewidmet 相似文献
865.
866.
M. Henriksson L. Sjöqvist V. Pasiskevicius F. Laurell 《Applied physics. B, Lasers and optics》2007,86(3):497-501
An optical parametric oscillator using a periodically poled LiNbO3 crystal and a volume Bragg grating output coupler is presented. Signal and idler wavelengths of 2008 and 2264 nm were generated
from the 1064 nm Nd:YVO4 pump laser. The Bragg grating was reflecting in a narrow band around 2008 nm, creating a purely singly resonant cavity. Signal
and idler linewidths of approximately 0.44 and 0.72 nm, respectively, were measured. This is a reduction of 80 and 60 times
compared to when using a mirror as output coupler. A total output energy of 156 μJ was measured with 47% slope efficiency.
PACS 42.65.Yj; 42.72.Ai; 42.40.Eq 相似文献
867.
G. M. Henkin 《Proceedings of the Steklov Institute of Mathematics》2006,253(1):195-211
A comprehensive answer is given to two related questions: (i) Can continuous functions be approximated by holomorphic ones on Jordan curves in ?n (A.G. Vitushkin, 1964)? (ii) Is any Jordan curve in ?n holomorphically convex (E.L. Stout, 1970)? 相似文献
868.
S.B. Lyubchik L.P. Tikhonova O.L. Galushko I.M. Fonseca 《Applied Surface Science》2006,252(17):6084-6088
Selective adsorption of platinum group metals (PMG) on activated carbons from a multi-component model and technological solutions was proposed for the preparation of heterogeneous-supported catalysts. Activated natural anthracites and a nitrogen-containing synthetic carbon are considered as carriers for Pd-supported catalysts. Their catalytic activity was studied in the Pd-catalyzed reactions of hydrogen peroxide decomposition and chloride ions oxidation by manganese(III). On the base of the obtained results, novel high sensitive analytical methods both for direct determination of supported-metal quantity and palladium oxidation states on the surface of spent adsorbents are suggested. 相似文献
869.
870.
B. Giner I. Gascón A. Villares C. Lafuente 《Journal of Thermal Analysis and Calorimetry》2006,83(3):735-745
The
relation between refractive index deviations and excess volumes for binary
mixtures formed by a cyclic ether and a haloalkane has been tested using several
methods: refractive index mixing rules and equations of state. Refractive
index deviations, excess volumes and molar refractions have been calculated
from experimental data of refractive indices and densities at two temperatures
298.15 and 313.15 K. Results obtained have been discussed in terms of intermolecular
interactions. Refractive indices were compared with those predicted by several
mixing rules. Excess volumes have also been correlated using several cubic
equations of state and finally a relation between parameter b
from equations of state and molar refraction has been provided. 相似文献