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41.
P. Ackerbauer J. Werner W. H. Breunlich M. Cargnelli M. Jeitler P. Kammel J. Marton N. Nägele A. Scrinzi J. Zmeskal J. Bistirlich K. M. Crowe C. Petitjean R. H. Sherman P. Baumann H. Bossy H. Daniel F. J. Hartmann W. Schott T. von Egidy W. Neumann 《Hyperfine Interactions》1993,82(1-4):357-372
A main source of information about the muon-catalyzed fusion cycle in D-T mixtures are the cycling rates c, which are characteristic for the kinetic equilibrium of states attained rapidly in dense targets. The measurement, analysis and interpretation of these rates will be discussed, concentrating on the extensive set of rates observed at PSI over the last decade in gaseous, liquid and solid targets.Invited talk presented by Peter Kammel. 相似文献
42.
Abe F Albrow M Amidei D Anway-Wiese C Apollinari G Atac M Auchincloss P Azzi P Baden AR Bacchetta N Badgett W Bailey MW Bamberger A de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Beretvas A Berge JP Bertolucci S Biery K Bhadra S Binkley M Bisello D Blair R Blocker C Bodek A Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A 《Physical review D: Particles and fields》1993,48(3):998-1008
43.
P. Brüesch F. Stucki Th. Baumann P. Kluge-Weiss B. Brühl L. Niemeyer R. Strümpler B. Ziegler M. Mielke 《Applied Physics A: Materials Science & Processing》1993,57(4):329-337
In this contribution we have studied the key electrical parameters of silica aerogels and of silica-aerogel-based composites, namely the dielectric constants , the dielectric losses tan (at 1 kHz), and the breakdown fields E
b (at 50 Hz). For low-density bulk silica aerogels we find =1.25 and tan =0.0005. E
b is about 500 kV/cm in quasi-homogeneous fields, and of the order of MV/cm in strongly inhomogeneous fields. The dielectric constants of partially densified aerogels increase linearly with density; their dielectric losses are relatively large and their breakdown fields are comparativiely low. The same results are found for aerogels in the form of settled materials, i.e. aerogel granules and powders in air. Acrylate-based aerogel composites with volume fractions larger than 70% have low dielectric constants but their losses are at least 10 times higher than those of low-density aerogels. These materials sustain high local fields in the MV/cm region, while in quasihomogeneous fields, breakdown occurs at about 100 kV/cm. Based on the present results and the interplay with other physical properties (low mechanical resistance, low thermal conductivity, adsorption of water, etc.), silica aerogels and silica aerogel-acrylate-based composites are predicted to have a low potential for electrical insulation. 相似文献
44.
45.
46.
Burlakov VV Arndt P Baumann W Spannenberg A Rosenthal U Parameswaran P Jemmis ED 《Chemical communications (Cambridge, England)》2004,(18):2074-2075
The 2,5-dititanabicyclo[2.2.0]hex-1(4)-ene (bis-titanocene-mu-(Z)-1,2,3-butatriene complex)3 is formed starting from [Cp2Ti(eta2-Me3SiC2SiMe3)] by in situ generated titanocene and 1,4-dichlorobut-2-yne via the 1-titanacyclobut-3-yne (2). 相似文献
47.
Ursula Baumann 《Fresenius' Journal of Analytical Chemistry》1963,193(6):456
Ohne Zusammenfassung
Folin, O.: Hoppe-Seylers Z. physiol. Chem. 41, 223 (1904); vgl. diese Z. 44, 459 (1905). 相似文献
48.
Scanning electron microscopy (SEM) with energy-dispersive X-ray microanalysis (EDX) is frequently used for morphological and qualitative chemical characterization of different materials. The applicability of this method for phase identification, is, however, often underestimated. The application of SEM/EDX for the characterization of different phases in fresh and altered municipal-waste incinerator bottom-ash samples with high lateral resolution is presented. Polished thin sections were prepared from the samples, but fresh fracture surfaces were also used. The EDX analyses were performed by using the correction procedures of a conventional standardless ZAF correction, a peak-to-background ZAF correction, and a correction method for light-element analysis. Because of their highly reactive properties the bottom-ash SEM samples require a special method of preparation. The method facilitates nondestructive preparation of the sensitive bottom-ash alteration phases (e.g. cement phases, hydroxides, salts) and their microstructures. 相似文献
49.
Nitrogen ion implantation (24 keV, 4.6 × 1017 cm?2) into (100) a p‐type silicon wafer material and a subsequent electron beam annealing at 1100 °C for 15 s under high vacuum conditions leads to the formation of an uneven surface in the implanted region caused by nitrogen bubbles beneath the surface. Annealing at 1200 °C for 300 s results in surface cavities with a mean diameter of 350 nm and a surface coverage of 3–4% and an average depth of ~60 nm. Nuclear reaction analysis reveals that the nitrogen concentration in the as‐implanted state exceeds 57 at%, the value of stoichiometric Si3N4. Annealing at 1100 °C for 15 s slightly reduces the nitrogen peak concentration, whereas annealing at 1200 °C for 300 s induces a significant alteration to the shape of the nitrogen depth profile coupled with the lowering of the concentration close to the stoichiometry of Si3N4. The results present a new method of producing sub‐micrometre cavities embedded in a thin silicon nitride film on wafer silicon which may lead to novel micro‐electronic and biotechnology applications. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
50.
H. Kaupp H. -P. Didra C. Kramer M. Baumann 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,27(4):307-312
Depolarization of excited114Cd 5s5p 3 P 1 atoms induced by collisions with various molecular gases (N2, H2, D2, CO, CO2, CH4, C2H6, C2H4) has been investigated using polarized fluorescence spectroscopy. After pulsed optical excitation of the Cd 53 P 1 level with appropriately polarized light the temporal behaviour of Zeeman quantum beats has been observed showing the influence of collisional destruction of orientation and alignment. By analyzing the signal curves at different molecular gas pressures the corresponding depolarization cross sections for114Cd atoms in the 53 P 1 state have been obtained. With regard to a test of a nuclear spin decoupling model for the collisions the cross sections were compared with previously measured hyperfine structure transfer cross sections of113Cd 5s5p 3 P 1 atoms. 相似文献