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51.
52.
K. Merz 《Commentarii Mathematici Helvetici》1935,8(1):379-381
Ohne Zusammenfassung 相似文献
53.
Michael Mastalerz Iris M. Oppel Klaus Merz Gerald Dyker 《Journal of inclusion phenomena and macrocyclic chemistry》2009,64(1-2):157-161
The crystal structures of a tetradentate pyridylcalix[4]arene ligand and its first copper(II) complex are discussed. The metal free ligand is mainly self-assembled by dipole–dipole interactions and a combination of CH–N bonds and CH–π interactions. The corresponding copper(II) perchlorate complex exhibits a self-inclusion behaviour to supramolecular zig-zag polymers. 相似文献
54.
55.
Th. Kuehl R. Bock S. Borneis E. Brambrink H. Brand J. Caird E. M. Campbell K. Cassou E. Gaul S. Goette C. Haefner T. Hahn H. M. Heuck D. H. H. Hoffmann D. Javarkova A. Klisnick H.-J. Kluge S. Kunzer T. Merz P. Neumayer P. Nickles M. D. Perry D. Reemts D. Ros M. Roth S. Samek W. Sandner G. Schaumann F. Schrader W. Seelig A. Tauschwitz R. Thiel D. Ursescu P. Wiewior U. Wittrock B. Zielbauer 《Hyperfine Interactions》2005,162(1-4):55-62
The high-energy high-power laser system PHELIX (Petawatt High Energy Laser for heavy Ion eXperiments) [1] is currently under construction at the Gesellschaft fuer Schwerionenforschung mbH (GSI) Darmstadt. With PHELIX GSI will
offer the unique combination of a high-current, high-energy (GeV/u) heavy-ion beam with an intense laser beam. This will open
the door to a variety of fundamental science issues in the field of atomic physics, plasma physics and nuclear physics. The
project will gain further interest in the near future by the dramatic increase of the accelerator performance with the starting
FAIR project at GSI [2]. This paper reports the current status of the project as well as the laser architecture. The proposed physics program and
a first experiment carried out with PHELIX, the realization of a transient collisionally excited x-ray laser [3], will also be reviewed briefly. 相似文献
56.
In this paper we develop a mathematical model describing the oxidation process of silicon. At first we introduce a model with a sharp reaction front between the silicon and the oxide layer. From this we turn over to a phase field model where the reaction front is replaced by an extended reaction zone. The silicon dioxide and the silicon are regarded as components of a reacting mixture, and the oxygen is assumed to be dissolved in it. We formulate a local existence result of that second model in three space dimensions assuming some simplifications concerning the boundary conditions and solve the complete free boundary value problem numerically. For this, it has been implemented into the process simulator DIOS which allows two-dimensional computations. 相似文献
57.
R. Grieser G. Bönsch S. Dickopf G. Huber R. Klein P. Merz A. Nicolaus H. Schnatz 《Zeitschrift für Physik A Hadrons and Nuclei》1994,348(2):147-150
The transition frequencies of thei-component of the R(99)15-1 and thew-component of the R(85)26-0 transition in the B-X system of molecular127I2 have been determined with an overall relative standard uncertainty of 1.3 · 10?10. For this purpose a commercial linear dye laser has been modified and stabilized to the corresponding iodine line. This dye laser serves as a transportable frequency standard which is compared with the wavelength standards of the PTB. The evaluation of an experiment for testing special relativity at the test storage ring (TSR) in Heidelberg is based on the precision of the reported interferometric wavelength comparison. 相似文献
58.
R. Grieser P. Merz G. Huber V. Sebastian P. Seelig M. Grieser R. Grimm I. Lauer V. Luger H.J. Miesner D. Schwalm A. Dax T. Engel M. Gerlach T. Kühl H. Winter 《Hyperfine Interactions》1997,108(1-3):241-250
Heavy ion storage rings allow for tests of the structure of local space time via the Doppler effect. At the TSR/Heidelberg
an experiment with high resolution laser spectroscopy at 7Li+ is performed. To gain the maximum resolution for saturation spectroscopy new methods of relativistic ion beam preparation
and diagnostics have been developed.
The laser cooling of the beam allows for precision determination of the mean velocity of the ions. A novel phase synchronous
detection scheme, ultimately sensitive to single ions, gives insights into the cooling mechanism and dynamics. With an additional
synchronous excitation scheme systematic uncertainties of the test experiment can be drastically reduced. After separation
of the ground state ions from the triplet states of 7Li+ by the combination of laser and electron cooling, a bunched and cooled ensemble of fast moving high precision clocks with
minimized perturbations by space charge effects and intra beam scattering is available.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
59.
60.
This article examines what it means to patent a gene. Numerous ethical concerns have been raised about the effects of such patents on clinical medical practice as well as on research and development. We describe what kinds of inventions are covered by human gene patents, give several examples and summarize the small body of empirical research performed in the US examining the effects of these patents. There is little evidence that early fears about gene patenting placing substantial restraints on research and clinical medicine have come to fruition. Nonetheless, there are areas of concern, and policy makers, physicians and the public should be alert to ensure that the net social benefits of patenting human genes are maintained. 相似文献