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101.
Adéla Kochanovská 《Czechoslovak Journal of Physics》1954,4(1):34-46
— —10
–4 —10
–2 . , . , , , , , . 相似文献
102.
Ohne Zusammenfassung 相似文献
103.
The first step in decommissioning of NPP is connected with defueling and successful disposal of liquid radioactive wastes (LRW), both from previous production and all work connected with this step. These require precise knowledge about the concentration of radioactive nuclides presented, especially alpha-emitters in all material fluxes arising in sich work (namely shut-down after some accident). This paper reports, results of the determination of U, Pu, Am and Cm by means of both the commonly used and the newly developed radiochemical procedures in various types of materials, e.g., LRW, aerosol filters, ashes resulted from incineration technology, metal surfaces, decontamination solutions etc. 相似文献
104.
The bonding of C2H2 in the nickel complexes [π-(C2H2)Ni(CO)2], [π-(C2H2)Ni(CNH)2] and [μ2-(C2H2) {NI(CNH)2}2] has been studied by the non-empirical self-consistent Hartree—Fock—Slater-LCAO method. Calculations have been performed, not only for these complexes, but also for free C2H2 and its substituted analogues, propyne, but-2-yne and hexafluorobut-2-yne, and for the mono- and dinuclear complex fragments, [Ni(CNH)2] and [{NI(CNH)2}2], which interact with the C2H2 molecule. The main difference with nickel surfaces, which have analogous π and μ2 adsorption sites for C2H2 that we have studied by the same method, is the much stronger 3d, 4s, 4p hybridization induced by the CNH and CO ligands. In the bis(diisocyanide—nickel) complex these hybrids form a rather broad dsp “band”. The low lying occupied levels in this “band” cause a strong interaction with the filled acetylene πu orbitals which dominates the π to metal donation effect. In the mononickel—acetylene complex this donation does occur, however, just as for acetylene adsorbed on nickel surfaces (in combination with the more prominent metal to π* back donation which we find in all cases). A linear relation has been derived between the CC stretch frequencies in coordinated C2H2 molecules and the calculated CC overlap populations. Substitutio of the H atoms in (free) C2H2 by CH3 or CF3 groups has almost no effect on the CC overlap population and force constant. 相似文献
105.
F. H. Müller H. Zahn Karl Jäckel Ad. Engelter F. Bielich 《Colloid and polymer science》1955,143(2):108-110
Ohne Zusammenfassung 相似文献
106.
Jiří Adámek 《Algebra Universalis》1982,14(1):140-166
A subset system Z is a function, assiging to each posetX a collectionZX of its subsets. We studyZ-continuous universal algebras, i.e., ordered algebras such that their domains have, and their operations preserve, joins of allZ-sets. A construction of the freeZ-continuous algebras is exhibited for an arbitraryZ. It turn out that only four subset systems have to be considered: the systemZX of (i) all ε-chains inX; (ii) all finite subsets ofX; (iii) all countable subsets ofX and (iv) the void set alone. The free algebras are described concretely for these four cases. 相似文献
107.
108.
Adéla Kochanovská 《Czechoslovak Journal of Physics》1954,4(3):381-383
109.
Ad Lagendijk 《Solid State Communications》1979,29(8):593-595
We present the first realistic mode-coupling calculation of the high-temperature EPR linewidth of a two-dimensional antiferromagnet. The theory is valid for temperatures where the linewidth is determined by diffusion-controlled dynamics. The angular and temperature dependence of the linewidth are in good agreement with experiment, although the absolute values are somewhat too small (∽40%). 相似文献
110.
van der Eerden AM Visser T Nijhuis TA Ikeda Y Lepage M Koningsberger DC Weckhuysen BM 《Journal of the American Chemical Society》2005,127(10):3272-3273
Atomic XAFS is a very attractive technique for probing electronic properties of supported metal nanoclusters. For platinum nanoparticles on different supports, the technique is found to be in good agreement with infrared CO adsorption measurements. The advantages of AXAFS, however, are that no probe molecule is required and that real-time measurements under reaction conditions are possible. 相似文献