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31.
Josef Šlapal 《Aequationes Mathematicae》1995,49(1):115-121
Summary For every ordinaln > 1 we define a categoryT
n
of topological spaces in ech's sense which is isomorphic to a category ofn-ary monorelational systems. We show that every categoryT
n
is an exponential supercategory of the categoryB of finitely generated topological spaces, which means that well-behaved function spacesG
H
can be defined inT
n
wheneverG B. 相似文献
32.
33.
V. Hnatowicz J. Kvítek V. Švorčík V. Rybka V. Popok 《Czechoslovak Journal of Physics》1994,44(6):621-627
Samples of polyethylene (PE) loaded with carbon black up to 8 wt.% and implanted with 150 keV Sb+ ions to the doses from 2×1013–2×1015 cm–2 were studied using standard Rutherford Back Scattering (RBS) technique. On the PE samples implanted to the doses above 2×1014 cm–2, a considerable surface carbonization is observed. The measured parameters of the Sb depth profile are compared with theoretical TRIM estimations. The projected range is by 25% lower than the theoretical one and the range straggling is about twice of that predicted. The differences are explained by stepwise polymer degradation during the ion bombardment. Strong oxidation of the ion implanted polymers is also observed. The oxygen depth profiles from the sample surface up to the depth comparable with Sb+ ion range evolve from nearly uniform one for low ion doses to highly non-uniform one for doses above 1×1015 cm–2. The total oxygen content in the sample surface layer 300 nm thick reaches a maximum for the doses of (1–2)×1014 cm–2.On leave from Belorussian State University, 220050 Minsk, Belarus.The authors thank the member of electrostatic accelerator group at INP for help during RBS measurements. The work was partly (V.H. and J.K.) supported by the Internal Grant Agency of the Academy of Sciences of Czech Republic under the grant No. 14805 and by the Internal Grant Agency of the Ministry of Education of Czech Republic under the grant No. 1002 (V.., V.R., V.H. and J.K.). In the final stage, the work was also supported by the Grant Agency of Czech Republic under the grant No. 202/93/0121. 相似文献
34.
M. Veselský Š. Šáro F. P. Heßberger V. Ninov S. Hofmann D. Ackermann 《Zeitschrift für Physik A Hadrons and Nuclei》1996,356(1):403-410
Velocity distributions and production cross sections of evaporation residues have been measured in the reaction20Ne+208Pb at projectile energies of 8.6, 11.4, 14.9 A.MeV. Essential deviations from statistical model of deexcitation have been
observed. Monte Carlo simulations involving emission of non-equilibrium particles have been used in order to reproduce experimental
velocity, charge and mass distributions of evaporation residues and to estimate indirectly multiplicities of pre-equilibrium
particles.
Communicated by V. Metag 相似文献
35.
Zusammenfassung Die schon früher beschriebene gasvolumetrische Methode zur N-N-Gruppenbestimmung durch Oxydationsaufschluß mit Chromsäure wurde zur Bestimmung des heterocyklischen Stickstoffes in Indazolinonderivaten mit Erfolg benützt und dadurch weiter die allgemeine Anwendbarkeit der Methode bestätigt. Enthält die Substanz gleichzeitig Amino- oder Nitrogruppen, können diese aus derselben Einwaage als Ammoniak bzw. Salpetersäure bestimmt werden.
XXVII. Mitteilung, siehe1. 相似文献
Analytical aspects of the oxidation of organic nitrogen compounds with chromic acid
Summary The gas volumetric method for determining N-N groups by oxidative fusion with chromic acid (which has already been described previously) was successfully employed to determine the heterocyclic nitrogen in indazolinone derivatives. The general applicability of the method was thereby confirmed. If the substance contains amino or nitro groups at the same time, these can be determined in the same sample as ammonia or nitric acid.
XXVII. Mitteilung, siehe1. 相似文献
36.
V. Ščasnár M. Zemánek L. Šoltés M. Lukácsová 《Journal of Radioanalytical and Nuclear Chemistry》1989,134(2):433-436
An HPLC method was developed for studying the stability of [3H] stobadin stored in physiological saline or buffers at various pH. Optimum conditions for the separation of degradation products were elaborated. A high-performance liquid chromatograph equipped with a radioactivity detector was used. 相似文献
37.
P. Kratochvíl B. Smola I. Stulíková P. Vostrý F. Jandoš J. Šedivec 《Czechoslovak Journal of Physics》1985,35(3):257-260
Static softening of AISI 321 steel after cold and hot deformation characterizing the industrial thermomechanical treatment was studied by means of tensile tests and TEM. The deformation temperature, the strain and the grain size were the main parameters determining the final softening. The results can be applied for optimization of the solution annealing. 相似文献
38.
In the present paper we report the first experimental results on ac and dc conductivity and permittivity of adenine hemisulphate hydrate and adenine sulphate measured at atmospheric and high hydrostatic pressures. For both materials ac conductivity is of
s type, where:s 1·1· Room temperature dc conductivity of adenine hemisulphate hydrate equals approximately 5×10–15
–1 cm–1 with an activation energy of 0·86 eV; dc conductivity of adenine sulphate is less than 10–16 cm–1. On the basis of these measurements and those carried out at high pressure, it is concluded that conductivity of adenine hemisulphate hydrate is of electronic type.The authors wish to thank Dr. J. Zachová for the preparation of adenine salts single crystals. 相似文献
39.
We calculate the density of states for the nondegenerate Anderson model for various values ofu=U/ andn
f
using the perturbation theory withu as the expansion parameter. Summing all the -independent self-energy diagrams, we use the Friedel sum rule and Ward identities to express the physical quantities in terms of the remaining -dependent part of the self-energy, which we evaluate to the 2nd order. The results for the spin and charge susceptibilities obtained in such a way compare rather well with the Bethe-ansatz results. The density of states exhibits different features in different parts of the parameter space. In Kondo region (u>1,n
f
1, i.e., –
f
~U/2), we obtain a many-body resonance (half-width T
K
) around the Fermi level and two broad peaks () at about
f
+n
f
U and
f
+U. In the VF region (u>1, and |
f
|) we obtain only two peaks (), one at about
f
and one between
f
+n
f
U and
f
+U. The consequences regarding the shape of the photoemission and inverse photoemission spectra of Ce intermetallics are discussed. 相似文献
40.
Zusammenfassung Eine Reihe von Metallkomplexen des 2,5-Dibenzoyl-3,4-dihydroxy-selenophens wurden spektroskopisch untersucht. Das Verhalten des Wismutkomplexes und die Möglichkeiten einer spektrophotometrischen Wismutbestimmung auf diesem Wege wurden eingehend studiert.
Herrn Univ.-Prof. Dr.Hans Lieb zum 80. Geburtstag gewidmet. 相似文献
Summary A spectroscopic examination was made of a series of metal complexes of 2,5-dibenzoyl-3,4-dihydroxyselenophen. The behavior of the bismuth complex and the possibilities of a spectrophotometric method of determining bismuth in this manner were studied thoroughly.
Herrn Univ.-Prof. Dr.Hans Lieb zum 80. Geburtstag gewidmet. 相似文献