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91.
92.
N. Kukhtarev G. Dovgalenko J. Shultz G. Salamo E. J. Sharp B. A. Wechsler M. B. Klein 《Applied Physics A: Materials Science & Processing》1993,56(4):303-305
We report the first measurement of the photo-galvanic circular current antisymmetric tensor component in BaTiO3: Co. The measurement gives a value of this coefficient, for extraordinary beam amplification, of 4×10–9 A/W using a nonstationary measurement technique at a wavelength of 0.632 m.Professor N. Kukhtarev is on leave from the Institute of Physics in the Ukraine and is supported by the NSFDr. G. Dovgalenko is on leave from the IRPA Rotor-Control research laboratory of the Ukraine and is supported by the University of Arkansas 相似文献
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E. Blasius K.-P. Janzen W. Adrian W. Klein H. Klotz H. Luxenburger E. Mernke V.B. Nguyen T. Nguyen-Tien R. Rausch J. Stockemer A. Toussaint 《Talanta》1980,27(2):127-141
Exchangers with cyclic polyethers as anchor groups have a large range of applications such as separations of cations with a common anion, of anions with a common cation, and of neutral organic compounds, and the determination of water by elution chromatography. Some crown ether monomers, especially 4- and 4,4′-alkyl-substituted benzo-derivatives are suitable for extractions and their adducts with heteropoly acids are used as liquid ion-exchangers. The exchangers are also applied in thin-layer chromatography and thin-layer electrophoresis. Furthermore the exchangers are successfully used in preparative chemistry, e.g., in salt conversions in order to isolate salts which are difficult to prepare by other means, in isolation and purification of organic compounds, and for anion activation in organic reactions. 相似文献
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As supported PtxNi1–x catalysts are used for hydrogenation reactions, it seemed necessary to assess the surface composition of the reduced samples. To approach the usual reduction conditions we applied in situ reduction in a reaction chamber (1 mbar H2 up to 500 °C) placed in ultra high vacuum recipient (UHV: 10–9 to 2.10–10mbar). All ion scattering spectroscopy measurements were performed in UHV. Charging of the samples was avoided by electron bombardment (5 eV). The variation of the surface composition was determined after subsequent sputtering, thermal treatment at 500 °C and during oxygen adsorption. A comparison with previous results of surface compositions of binary alloys (polycrystalline foils [1, 2] and single crystals PtxNi1–x [3]) is given.Dedicated to Professor Dr. rer. nat. Dr. h. c. Hubertus Nickel on the occasion of his 65th birthday 相似文献
99.
Vapor pressure measurements and small angle scattering (SANS) experiments are reported and discussed for bispiperidinium (BP) bromide and n-tetrapentylammonium bromide solutions in methanol at 25°C. The BP+ ion which may be considered as a tetraalkylammonium (TAA) ion with pairwise connected alkyl chains, is used for the study of the effects due to flexible TAA alkyl chains. SANS intensities are calibrated with the help of the precise osmotic coefficients from the vapor pressure measurements. 相似文献
100.
Andreas Stockhammer Klaus-Hermann Dahmen Tobias Gerfin Luigi M. Venanzi Volker Gramlich Walter Fetter 《Helvetica chimica acta》1991,74(5):989-992
The cluster compounds [Pt3(μ-CO)3(PR3)3] act as Lewis bases towards the metal halides of Group XI, MX, Group XII, MX2, and Group XIII, MX3, to form cluster compounds of the composition [{MXn}{Pt3(μ-CO)3(PR3)3}]. The X-ray crystal structure, NMR and IR data are given for the compound [{ZnI}{Pt3(μ-CO)3(PPh(i-Pr)2)3}]. 相似文献