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91.
This is a survey on geometric constructions in multifractal analysis of measures. We show that the multifractal formalism introduced by Olsen [Ol11] and Peyriére [Pey] leads to a multifractal geometry for product measures, for slices of measures (i.e. intersections of measures with lower dimensional subspaces), and for general intersections of measures, which is analogous to the fractal geometry for product sets, for slices of sets (i.e. intersections of sets with lower dimensional subspaces), and for general intersections of sets, respectively.  相似文献   
92.
93.
Four equidistant peaks are observed below the Kα1,2 line in the X-ray spectra of Na, Al, Si, SiO2, Ca, Sc and Ti, produced by oxygen bombardment. With much weaker intensity, these lines are also seen in proton excitation. The lines are interpreted to be due to the excitation of one or more volume plasmons in the target material by the Kα1,2 X-ray decay.  相似文献   
94.
Recently gas jet targets have been used for the study of small momentum transfer p-p and p-d elastic and inelastic scattering. In these experiments, which were performed at Serpukhov in the USSR and at the Fermilab in the USA, the gas jet is introduced in the main ring of the accelerator. We review the techniques associated with these measurements and summarize the published results which cover 4-momentum transfers 0.001< |t|< 0.12 (GeV/c)?2 and incident energies 8<E< 400 GeV. Elastic scattering data have yielded precise values for the slope of the nuclear scattering amplitude and for the ratio of the real to imaginary part as a function of energy. The implications of these data on the understanding of high energy hadronic interactions are discussed in some detail. We also present and discuss information on the diffractive dissociation of the proton to low mass states, obtained from inelastic scattering using the gas jet target.  相似文献   
95.
Previous work has shown that atomic sulfur irreversibility modifies polyethylene, presumably through an insertion reaction into carbon—hydrogen bonds with formation of surface thiol groups. The thiol groups were then oxidized to sulfonic acid surface groups, which were further reacted chemically as shown by wettability measurements. In this work the thiol group was bypassed and the surface sulfonic acid groups were obtained by exposing the polyethylene surface directly to fuming sulfuric acid. The sulfonic acid groups were reacted further. Critical surface tension values identical with those in the previous work with atomic sulfur were obtained, thus substantiating the previous work.  相似文献   
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98.
Two high temperature beryllium allotropes have been stabilized at room temperature through the addition of transition elements. Superconductivity has been observed in almost all of them. Beryllium films reported superconducting in the past appear in all probability to require the presence of transition element impurities, in order to show the phenomenon.  相似文献   
99.
The Chou-Yang model forpp elastic scattering, modified to include the effect of coupled inelastic channels, is used to fit recent data in the region of the dip, i.e., 1.0≦|t|≦2.0 (GeV/c)2 for incident momenta ranging from 35 to 250 GeV/c. Good quantitative agreement is found for an inelastic coupling which is predominantly real, as compared to the mostly imaginary elastic coupling. Implications for dips at highert, which are predicted by the model but as yet not observed experimentally, are discussed.  相似文献   
100.
The design and construction of a cone penetrometer for field use is described. The penetrometer is mounted on a frame to which two wheels are fitted for towing the device from one test site to the next. An electric motor drives the penetrometer during the test and simultaneous readings are performed of both cone depth and penetration resistance. The device weighs 70 kg and the maximum force on the cone typically exceeds 1.2 kN. The acquired data are transferred to a microcomputer and after each penetration the result is presented to the operator in graphic form. The microcomputer is equipped with a fairly large RAM memory which serves as storage medium for data during measuring work. Afterwards, data are easily moved to a mainframe computer for analysis.  相似文献   
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