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91.
92.
Study of multi-nucleon transfer reactions in 58, 64Ni + 207Pb collisions at the velocity filter SHIP
Comas V. F. Heinz S. Hofmann S. Ackermann D. Heredia J. A. Heßberger F. P. Khuyagbaatar J. Kindler B. Lommel B. Mann R. 《The European Physical Journal A - Hadrons and Nuclei》2013,49(9):1-17
The European Physical Journal A - We investigated multi-nucleon transfer reactions in collisions of 58Ni + 207Pb and 64Ni + 207Pb at Coulomb barrier energies. The new aspect is that we used a... 相似文献
93.
P. Svoboda J. Vejpravová M. Hofmann R. Schneider M. Rotter M. Doerr M. Loewenhaupt 《Czechoslovak Journal of Physics》2002,52(2):267-270
Intermetallic compound TmCu2 crystalizes in the orthorhombic structure, orders antiferromagnetically (AF) and exhibits four different AF phases below T
N = 6.5 K. In all these phases the Tm magnetic moment is parallel to the b-axis. The ground-state AF1 (T < 3.4 K) corresponds to the squared-up AF structure with propagation vector
01 = (5/8, 0, 0) and magnetic unit cell 8a × b × c. Narrow phases AF2 and AF3 (3.3 K < T < 3.7 K and 3.6 K < T < 4.6 K) are 'spin-slip'-derivatives from the AF1 structure, yielding propagation vectors
02 = (0.633, 0, 0.02) and
03 = (0.618, 0, 0), respectively. The phase AF4 (4.4 K < T < T
N) is then incommensurate transversal spin-wave with the propagation
04 = (0.64, 0, 0). The co-existence of AF phases indicates the first-order transitions between them. 相似文献
94.
Tunable blue laser based on intracavity frequency doubling with a fan-structured periodically poled LiTaO(3) crystal 总被引:1,自引:0,他引:1
We introduce a new concept for a wavelength-tunable frequency-doubled laser diode with a single control parameter. The concept is based on intracavity frequency doubling in an external resonator geometry with spatial separation of the spectral components. The use of a fan-structured periodically poled LiTaO(3) crystal permits tuning of both the fundamental and the second harmonic simultaneously with one aperture. We demonstrate tunability over more than 10 nm in the blue (480.4 to 490.6 nm) with output powers of the order of 50 nW. 相似文献
95.
Campbell S. J. Klingelhöfer G. Kaczmarek W. A. Hofmann M. Nagel R. Wang G. 《Hyperfine Interactions》2002,139(1-4):407-416
Integral conversion electron Mössbauer spectroscopy has been used to investigate the phases and transformations which occur when -Fe2O3 is wet-milled in vacuum for up to 144 h. In addition to the transformation to off-stoichiometric Fe3–x
O4 observed previously by transmission Mössbauer spectroscopy, the room temperature ICEMS spectra reveal the presence of 10–15% -Fe2O3 on the surfaces of particles milled for more than 24 h. Time-of-flight neutron diffraction of an -Fe2O3 sample wet-milled for 200 h also provides evidence of the occurrence of a small fraction (4%) of -Fe2O3 in the milled product. The -Fe2O3 is likely to occur as a surface oxide layer and does not appear to play a significant role in the mechanochemical transformation of -Fe2O3 to Fe3–x
O4. 相似文献
96.
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99.
P. Hoffmann Th. Hofmann N. Pilz und K. H. Lieser 《Fresenius' Journal of Analytical Chemistry》1985,320(7):652
Ohne Zusammenfassung
Determination of actinides by x-ray fluorescence analysis, excitation by -emitters相似文献
100.
K. H. Lieser R. Sommer T. Hofmann P. Hoffmann 《Fresenius' Journal of Analytical Chemistry》1981,307(3):177-184
Summary If the concentration of elements with Z>22 (Ti) is to be determined in mineral samples and if the concentration of any of these elements is greater than 1%, the sample is diluted by grinding it together with an appropriate amount of quartz powder in an agate mortar mill. The diluted sample is measured in powdered form in a spectro-cup at practically infinite thickness by energy-dispersive X-ray fluorescence; the counting rates are corrected by means of the Compton scattering peak and evaluated by use of calibration curves obtained by measuring standards on the basis of silica gel. The applicability of this method is established by measuring the concentrations of 12 elements with Z>22 in 14 mineral samples of varying composition.We thank the Bundesministerium für Forschung und Technologie for financial support and the Uranerzbergbau GmbH, Bonn, for supplying the mineral samples. 相似文献