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51.
Jin-Seung Jung Kyong-Hoon Choi Yong-Rok Kim Leszek Malkinski Weilie Zhou Charles J O'Connor 《Journal of Physics and Chemistry of Solids》2003,64(3):385-390
Superparamagnetic nickel nanoparticles were prepared by incorporating nickel ion into AlMCM41 as a nanoreactor and then reduced with sodium borohydride or H2 gas. Products were characterized by elemental analysis, transmission electron microscopy, X-ray powder diffraction, and magnetic susceptibility. The nickel particle size and blocking temperature depend on the reduction method. 相似文献
52.
Leszek Szaro 《Surface science》1984,137(1):311-326
The simple theory of the surface photovoltage induced by photostimulated electron transitions from the bulk impurity levels is given. The relevant calculations show that the surface barrier height, the concentration of the impurity levels and the trapping process at the surface effectively control this phenomenon. Under the proper conditions, a very low excitation level in the bulk can generate significant surface photovoltage signals. 相似文献
53.
A simple method for determining the surface slope of a specimen under test in the high-sensitivity grating interferometry setup is proposed. The information on the derivative of out-of-plane displacement is obtained by software subtraction of two primary interferograms: a conventional one and one with diffraction orders laterally displaced in the image plane. Very good coincidence between the theoretical and experimental results has been obtained. The method can be used for studying static and transient events depending on the fringe pattern analysis method used. 相似文献
54.
Leszek Natkaniec Mikołaj F. Rudolf Bogusława Jeźowska-Trzebiatowska 《Theoretical chemistry accounts》1973,28(2):193-199
Results of SCCC MO calculations for the dimeric oxygen double-bridged [Mo2O4Cl4(H2O)2]2–ion are reported. On the basis of these results the previously reported spectra and magnetic properties may be explained. The strong direct molybdenum — molybdenum interaction in the Mo2O
4
2+
core was proved to exist.
Zusammenfassung Die Ergebnisse von SCCC MO-Rechnungen für das zweikernige Ion [Mo2O4Cl4(H2O)2]2– mit zweifacher Sauerstoffbrücke werden mitgeteilt. Danach können die früher angeführten magnetischen und spektralen Eigenschaften dieses Ions verstanden werden. Die Existenz starker unmittelbarer Molybdän-Molybdän Wechselwirkungen innerhalb des Mo2O 4 2+ Kerns wird nachgewiesen.
Résumé Résultats de calculs SCCCMO pour l'ion dimère Mo2O4Cl4(H2O) 2 2– . Sur la base de ces résultats les propriétés spectrales et magnétiques précédemment obtenues peuvent être expliquées. L'existence d'une forte interaction directe molybdène-molybdène dans le coeur Mo2O 4 2+ est clairement démontrée.相似文献
55.
Leszek Czuchajowski Stefan Goszczynski Dale E. Wheeler Antoni K. Wisor Tadeusz Malinski 《Journal of heterocyclic chemistry》1988,25(6):1825-1830
(R + S)Meso-[2.2]Paracyclophanyltriphenylporphyrin 3 , a member of a novel class of cyclophanylporphyrins, was obtained and characterized by spectroscopic and electrochemical methods. Compared to meso-tetra[2.2]paracyclophanylporphyrin 1, it represents a simplified structure designed for the investigation of electronic interactions between the [2.2]paracyclophane moiety and porphyrin core and for use in metallation reactions. 相似文献
56.
The combined CNDO/S and transition density matrix methods reproduced well the UV-VIS spectra of the intramolecular charge-transfer complexes of double- and triple-layered [2.2]paracyclophanequinones in which benzene and p-benzoquinone represent the donor and acceptor layers: DA, DDA and DAD. Calculations pointed to the already known experimental bathochromic shifts of the longest wavelength absorption band for the DADDADAD transformations. The electronic transitions corresponding to this band are for DA and DDA the CT transitions of the
* type; however, for DAD the band represents the n
* transition localized on the acceptor ring. 相似文献
57.
58.
Leszek Szybisz 《Zeitschrift für Physik A Hadrons and Nuclei》1974,269(2):139-145
Theβ-moments of the 7/2+(1.176 MeVβ ?)3/2+ transition in the decay of137Cs have been extracted from the available experimental data. We have obtained the following values: 〈R ij 〉/R 2=0.035±0.020, 〈iT ij 〉/R 2=0.067±0.036, and ?0.085≦〈S ijk ~>/R 2≦0.085. These results show that theβ-moments are reduced with respect to those evaluated by means of the conventional pairing model. These quenching effects are similar to those previously found in the analyses of first-forbiddenβ-decays and are attributed to residual charge-exchange interactions. The results forΛ(=?〈iA ij 〉/ξ〈R ij 〉) are discussed in the light of the predicitons of the CVC theory. 相似文献
59.
The increased interest in fish skin collagen results from the risk of BSE disease and the production of native collagen by the acidic hydration method. As a material, FSC derived by the novel acidic hydration method was used. The bovine Achilles tendon (BAT) collagen type I was applied as a control material. Measurements were carried out at the temperature range 2980 K-510 K. Each sample was heated twice. During the first heating run for FSC, to 380 K, the maximum was localized at 343 K, at electrical conductivity of 7 · 10−6 S/m. In the second heating run to 510 K, the maximum was observed at 443 K for FSC, and at 487 K for BAT collagen. The peaks revealed in the temperature range 320-350 K were related to the free water and bound water release, alike for FSC and BAT collagen. The process of water removal for both types of collagen takes place in similar temperature ranges. 相似文献
60.
Leszek Dziczkowski 《PAMM》2010,10(1):605-606
The paper proposes a method for simultaneous measurements of the material conductivity and its surface roughness for non-ferromagnetic materials. The method takes advantage of the effect exercised by eddy currents onto impedance of a contact coil. The essence of the method is to eliminate the influence of the surface unevenness onto measurements of conductivity by the calculation of a correcting factor that serves as a specific equivalent of the surface roughness. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献