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991.
Hans-Joachim Arnold 《Journal of Geometry》1981,16(1):83-92
In this article a construction is given of a wide class of weakly affine spaces in the sense of E. Sperner, namely of those, in which there exists a pair of points O, C, such that the structures at infinity (Fernräume), are isomorphic. The construction is based on algebraic methods using the so called Quasimodul (s. [7], [4], [2], [1]). 相似文献
992.
William E. Hull Erika Büllesbach Hans-Joachim Wieneke Helmut Zahn Hans R. Kricheldorf 《Magnetic resonance in chemistry : MRC》1981,17(2):92-96
The Bunte salt derivative was prepared from bovine insulin-A isolated from natural sources, and was purified by chromatography. Natural abundance 40.55 MHz 15N NMR spectra were measured in water and dimethyl sulphoxide. The latter solvent gave the best resolution, and 20 of the 22 possible amide nitrogen signals were detected. Several model oligopeptides were also measured and their usefulness for assignments is discussed. 相似文献
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Absolute photofission cross sections of 235,238U measured with tagged photons between 40 and 105 MeV
H. Ries U. Kneissl G. Mank H. Ströher W. Wilke R. Bergère P. Bourgeois P. Carlos J.L. Fallou P. Garganne A. Veyssière L.S. Cardman 《Physics letters. [Part B]》1984,139(4):254-258
Absolute photofission cross sections of 235,238U have been measured in the energy range 40–105 MeV with “tagged” photons, using parallel plate avalanche counters for a direct detection of the fission fragments. The measured cross sections are nearly constant in the investigated energy range and amount to about 17 mb for both isotopes. The results are compared with recent photoneutron data. 相似文献
999.
S. A. Payne C. D. Marshall A. Bayramian G. D. Wilke J. S. Hayden 《Applied physics. B, Lasers and optics》1995,61(3):257-266
The Nd-doped phosphate laser glass described herein can withstand 2.3 times greater thermal loading without fracture, compared to APG-1 (commercially available Average-Power Glass from Schott Glass Technologies). The enhanced thermal loading capability is established on the basis of the intrinsic thermomechanical properties (expansion, conduction, fracture toughness, and Young's modulus), and by direct thermally induced fracture experiments using Ar-ion laser heating of the samples. This Nd-doped phosphate glass (referred to as APG-t) is found to be characterized by a 29% lower gain cross section and a 25% longer low-concentration emission lifetime. Other measurements pertaining to the concentration quenching, thermal lensing, and saturation of the extraction are also described in this article. It is note-worthy that APG-t offers increased bandwidth near the peak of the 1054 nm gain spectrum, suggesting that this material may have special utility as a means of generating and amplifying ultrashort pulses of light. 相似文献
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