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21.
König M Tschetschetkin A Hankiewicz EM Sinova J Hock V Daumer V Schäfer M Becker CR Buhmann H Molenkamp LW 《Physical review letters》2006,96(7):076804
Ring structures fabricated from HgTe/HgCdTe quantum wells have been used to study Aharonov-Bohm type conductance oscillations as a function of Rashba spin-orbit splitting strength. We observe nonmonotonic phase changes indicating that an additional phase factor modifies the electron wave function. We associate these observations with the Aharonov-Casher effect. This is confirmed by comparison with numerical calculations of the magnetoconductance for a multichannel ring structure within the Landauer-Büttiker formalism. 相似文献
22.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
23.
Phytochemical studies of the leaves and rhizomes of Paraboea pa niculata (Gesneriaceae) are reported for the first time. Three phenylethanoid glycosides were isolated and characterized as 3,4-dihydroxyphenethyl-(3"-O-beta-D-apiofuranosyl)-beta-D-glucopyranoside, calceoralarioside E, and acteoside. These isolates exhibited weak cytotoxic activity against the K-562 cell line with a 50% of cell killing rate of 40.18 microM, 27.05 microM, and 27.24 microM, respectively. In the DPPH free radical scavenging assay, their IC50 values were determined as 75.89 microM, 25.00 microM, and 26.04 microM, respectively. 相似文献
24.
Solid phase extraction (SPE) using Sep-Pak? cartridges is one of the techniques used for fractionation of antioxidant compounds in waste of dabai oil extraction (defatted dabai parts). The aim of this study was to determine the phenolic compounds and antioxidant capacity in crude extracts and several SPE fractions from methanolic extract of defatted dabai pulp and peel. Based on SPE, Sep-Pak? cyanopropyl and C18 cartridges were used to fractionate the antioxidant-rich crude extracts into water and methanolic fractions. Analyzed using LC-MS, flavonoids, anthocyanins, saponin derivatives and other unknown antioxidative compounds were detected in the defatted dabai crude extracts and their SPE fractions. Anthocyanins were the major phenolic compounds identified in the defatted dabai peel and detected in most of the SPE fractions. Methanolic fractions of defatted dabai parts embraced higher total phenolics and antioxidant capacity than water fractions. This finding also revealed the crude extracts of defatted dabai peel have the most significant antioxidant properties compared to the methanolic and water fractions studied. The crude extract of defatted dabai parts remain as the most potent antioxidant as it contains mixture of flavonoids, anthocyanins and other potential antioxidants. 相似文献
25.
Hock KM 《Chaos (Woodbury, N.Y.)》1996,6(4):564-567
The Euler problem with two fixed point masses and one moving mass is reconsidered in the light of general relativity. The scattering of a particle by two fixed black holes is shown to be strongly chaotic. Two neutral black holes have been used for the study. The particle trajectories have been computed numerically using a modified muffin tin approximation. A plot of the scattering angle against impact parameter showing distinct signs of chaos is presented. (c) 1996 American Institute of Physics. 相似文献
26.
L. Hock B. Helferich K. Neumann F. Peters H. Schmidt W. Lauppe B. Roßmann 《Colloid and polymer science》1951,123(1):54-56
Ohne Zusammenfassung 相似文献
27.
Ohne Zusammenfassung 相似文献
28.
W. Scheele L. Hock J. Wolf B. Helferich Sippel Holluta 《Colloid and polymer science》1950,118(1):57-59
Ohne Zusammenfassung 相似文献
29.
D. H. Black H. Seibert A. Lehrman F. Friedrichs F. R. Winton G. Suge E. Zintl S. Neumayr P. van Campen L. Hock C. L. Nottebohm W. Dnane und Ch. A. Lory 《Fresenius' Journal of Analytical Chemistry》1931,83(7-8):289-294
Ohne Zusammenfassung 相似文献
30.
Crude palm oil contains 600 to 1000 ppm of tocols in the form of tocopherols and tocotrienols. These palm tocols have been isolated and analyzed in the past by various chromatographic techniques such as open column chromatography, high-performance liquid chromatography, as well as thin-layer chromatography. Supercritical fluid chromatography (SFC) has emerged as a more advanced chromatographic technique in recent years. The tocols present in palm oil are successfully isolated using SFC. Identification of these tocols is supported by various spectroscopic techniques such as 1H NMR, 13C NMR, and mass spectrometry. 相似文献