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991.
Neutron diffraction, magnetometric and Mössbauer effect experiments were performed on CoMnSn. The latter two agreed in giving transition temperature of 145 K. The canted magnetic moment arrangement was found and Sn atoms were proved to occupy several magnetically non-equivalent positions leading to significant distribution of hyperfine parameters. 相似文献
992.
M. Gogołwicz J. Warczewski T. Mydlarz I. Okońska-Kozłowska 《Journal of magnetism and magnetic materials》1985,50(1):49-52
For the polycrystalline samples of Mn1?xCuxCr2S4 (x = 0.85, 0.90, 0.95) the magnetization was measured in the temperature range between 77 K and the Curie temperature, TC, using a magnetic balance (Faraday's method) and pulsed magnetic fields up to 2.0 T. The magnetic susceptibility was measured between TC and about 600 K. The Curie temperatures were obtained using the kink point method.In the temperature range between 4.2 and 77 K the magnetization was measured in stationary magnetic fields up to 14 T. The data indicate a noncollinear ferrimagnetic structure. The compounds under investigation can be treated as CuCr2S4 slightly doped with Mn, with a valence distribution Mn2+1?xCu1+xCr3+2?xCr4+xS2?4. 相似文献
993.
M. Deutschmann R. Honecker K. Rumpf U. Kundt M. Walter U. Idschok R. Hartmann V.T. Cocconi T. Coghen S. Humble A. Kotański D.R.O. Morrison J. Figiel A. Guła P. Malecki B. Muryn L. Suszycki E. Leitner 《Nuclear Physics B》1975,85(1):31-38
The differential cross section for the charge-exchange process π+p → π0 (π+p) at 8, 16 and 23 GeV/c is presented for several regions of the π+p effective mass. It is found that the dip at t′ ≈ 0.6 (GeV/c)2 which is observed in the Δ(1236) mass band becomes a less pronounced structure in the higher mass regions. However, while the slope of the distributions in the near-forward direction decreases strongly with increasing π+p mass, there is no evidence that the observed structure moves to higher values of t′ as the π+p mass increases. These results are consistent with a Regge-exchange picture where the position of the dip is determined by the exchanged trajectory, but are inconsistent with a simple geometrical picture. 相似文献
994.
The nucleon emission induced by high-energy electrons is analysed in three experimental situations: electron-proton coincedence and single detection of electron or proton. The coincidence and proton detection experiments are recommended as sensible tools for studying the nuclear correlations. 相似文献
995.
Anion-exchangers loaded with SPADNS or Orange II or SPADNS + Nitroso-R salt are used for selective separation of bismuth and cadmium, which are then determined by AAS. 相似文献
996.
T. Głowiak W. Sawka-Dobrowolska B. Jeżowska-Trzebiatowska A. Antonow 《Journal of chemical crystallography》1980,10(1-2):1-10
The crystal and molecular structure of bis(aminomethylphosphonate)-copper(II), C2H10N2O6P2Cu, has been determined from MoK diffractometer data. The compound crystallizes in the monoclinic space groupP21/n witha =7.571(2),b = 4.943(1),c = 11.212(3) Å, = 105.84(2) °, andZ = 2. The structure was solved by the heavy-atom technique and refined by full-matrix least-squares methods toR = 0.041, using 1084 reflections for which ¦F
o¦ > 3.92 (¦F
o¦). In this complex, the Cu atom is square-planar coordinated by four O atoms from four phosphonic groups, and not by the amino group. The Cu-O bond lengths are 1.928(3) and 1.937(3) Å, and the phosphonic groups bridge adjacent Cu atoms in polymeric chains. The infrared spectrum of this complex is reported. 相似文献
997.
P. Wodniecki M. Marszałek B. Wodniecka A. Z. Hrynkiewicz 《Hyperfine Interactions》1993,78(1-4):319-321
The TDPAC technique was applied to study the formation of In-Pd compounds in bilayer electrodeposited sample doped with the radioactive111In. Subsequent isochronal annealings at increasing temperatures caused the Pd diffusion into the In layer reflected in the quadrupole interactionR(t) curves. The appearing new unique frequencies indicate the formation of ordered In3Pd, In3Pd2 andInPd2 phases in the sample. The identification of this In-Pd compounds was based on the PAC measurements for bulk In-Pd samples with defined stoichiometry. 相似文献
998.
Dr. Kazimierz Włodarczyk 《Monatshefte für Mathematik》1984,97(4):331-333
Bernstein's inequality (1) will be extended to polynomial maps of arbitrary complex Banach spaces; cf. (3). We also give conditions
for equality in (3). The extension of Bernstein's inequality to the case of polynomial maps of ℂ into ℂ was given byTung [4] and [5]. 相似文献
999.
Three Lennard-Jones binary liquid mixture systems obeying Lorentz-Berthelot rules, but having differing component sizes and energy parameters, have been used to calculate the local fractions of the two components around each type of central particle over the entire composition range from molecular-dynamics data. It is found that well-defined local fractions can be determined even in the case where the size difference between the particles is large. The results obtained are compared with values predicted by the Wilson and NRTL equations. It is confirmed that the NRTL equation gives satisfactory agreement only in the case of mixtures of components having the same size parameters. A new correlation is proposed by a modification of the NRTL equation. This correlation can predict reasonably well local-fraction data for all the Lennard-Jones liquid mixtures studied so far. 相似文献
1000.
Małgorzata Baśko Przemyslaw Kubisa 《Journal of polymer science. Part A, Polymer chemistry》2007,45(14):3090-3097
Cationic copolymerization of L,L ‐lactide (LA) and ε‐caprolactone (CL) initiated by low molecular weight diols in the presence of acid catalyst gives corresponding copolyesters terminated at both ends with hydroxyl groups in practically quantitative yield. Copolymerization proceeds by Activated Monomer mechanism. LA is consumed preferentially and at the later stages of copolymerization the reaction mixture is enriched with CL. In spite of that, random distribution of both units is observed and end‐groups are mainly ? LA‐OH groups and not ? CL‐OH groups. This is explained by the fact that to reach high conversion of both comonomers the relatively long reaction times are required and at those conditions transesterification reaction becomes significant. Thus the microstructure of copolymers and the nature of the end‐groups is governed by transesterification rather then by the kinetics of comonomers incorporation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3090–3097, 2007 相似文献