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991.
A.V. Andreev B. Janoušová V. Sechovský Y. Homma Y. Shiokawa 《Czechoslovak Journal of Physics》2002,52(2):275-278
We present the first single-crystal study of Fe and Ni doped U(Co1-x
T
x
)Al compounds in comparison to the parent compound, the itinerant 5f-electron metamagnet UCoAl. Magnetization and specific-heat data measured in the temperature range of (1.8-300) K and in fields up to 10 T are analyzed and discussed. Both compounds exhibit a strong uniaxial anisotropy with the dominating magnetic response along the c-axis of the hexagonal ZrNiAl-type structure. Ni substitution yields an increase of the critical field for metamagnetism; UCo0.95Fe0.05Al is ferromagnetic below 30 K. Temperature evolution of the entropy change between 0 and 10 T points to involvement of magnetic correlations or spin fluctuations in the paramagnetic compounds UCoAl and UCo0.95Ni0.05Al. 相似文献
992.
993.
D. Kaptás T. Kemény J. Balogh L. F. Kiss L. Gránásy I. Vincze 《Hyperfine Interactions》1994,94(1):1861-1865
The temperature dependence of the iron hyperfine field distribution is reported in melt-quenched amorphous Fe-Zr alloys. The most remarkable feature is the compositinal change in the shape of the average hyperfine field versus temperature curves. The unusual increase in the average hyperfine field below about 85 K is a characteristic feature of the RSG systems; however, no anomaly is observed in the width of the hyperfine field distribution as a function of temperature. The results cannot be properly explained in the framework of the existing spin glass models. 相似文献
994.
A quick sample preparation method was used for the determination of sulphur and trace metals in oil and oily products by the ICP with a minitorch. Stable aqueous emulsions of oils and oil products were made by using two kinds of emulsifiers (one with low sulphur content, the other sulfonated). Aqueous standard solutions can be used for the preparation of calibration solutions. The contents of S, Al, Cr, Cu, Fe, Mg, Ni and Pb in aqueous emulsions were determined and the results were in good agreement with the composition of oil standard solutions used for control analysis procedure. 相似文献
995.
We study extension of operators T: E→ L0([0, 1]), where E is an F–function space and L0([0, 1]) the space of measurable functions with the topology of convergence in measure, to domains larger than E, and we study the properties of such domains. The main tool is the integration of scalar functions with respect to stochastic
measures and the corresponding spaces of integrable functions.
Partially supported by D.G.I. #MTM2006-13000-C03-01 (Spain). 相似文献
996.
997.
We reported controllable synthesis of ZnS nanocrystal-polymer transparent hybrids by using polymethylmethacrylate (PMMA) as
a polymer matrix. In a typical run, the appropriate amounts of zinc chloride (ZnCl2) and sodium sulfide (Na2S) in the presence of 2-mercaptoethanol (ME) as the organic ligand were well dispersed in H2O/dimethylformamide solution without any aggregation. In addition, the Mn-doped ZnS nanocrystals (NCs) were synthesized with
similar method. Then, ZnS-PMMA hybrids were obtained via free radical polymerization in situ by using ZnS NCs functionalized
with methacryloxypropyltrimethoxysilane (MPS). FT-IR characterization indicates the formation of robust bonding between ZnS
NCs and the organic ligand. The TEM images show that ZnS NCs are well dispersed in PMMA matrix, and particle size of as-prepared
ZnS NCs is about 2.6 nm, in agreement with the computing results of Brus’s model and Debye–Scherrer formula. The photoluminescence
measurements present that ZnS NCs, Mn-doped ZnS NCs, and ZnS/PMMA hybrid show good optical properties. 相似文献
998.
We study a degenerate nonlinear variational inequality which can be reduced to a multivalued inclusion by an appropriate change
of the unknown function. We establish existence, uniqueness and regularity results. An application arising in the theory of
water diffusion in porous media is discussed as an example.
相似文献
999.
A new flow electrical conductance instrument was constructed and tested on dilute NaCl solutions up to 458 K, and on more
concentrated solutions (maximum 0.436 mol⋅kg−1) at 373 K. The results of the new instrument agreed with those of previous authors within the estimated experimental errors.
The model of Bernard et al. (J. Phys. Chem. 96, 3833–3840 (1992), MSA) was found to represent the high-temperature results without introducing an ion-pairing equilibrium constant. The Fuoss–Hsia
conductance equation as given by Fernandez-Prini was found to represent the dilute concentrations with Λ° (NaCl) as the only adjustable parameter. It was found that Λ° (NaCl) could be expressed as a function of solvent viscosity and density by using three parameters found by regression of
literature results between 278.15 and 523 K. This equation along with the FHFP theory permits the equivalent conductivity
of dilute sodium chloride solutions to be calculated within the accuracy of the existing experimental measurements. 相似文献
1000.
An interval-parameter fuzzy linear programming method (IFMOLP) is proposed in this study for multiple objective decision-making
under uncertainty. As a hybrid of interval-parameter and fuzzy methodologies, the IFMOLP incorporates interval-parameter linear
programming and fuzzy multiobjective programming approaches to form an integrated optimization system. The method inherits
advantages of interval-parameter programming, and allows uncertainties and decision-makers’ aspirations to be effectively
communicated into its programming processes and resulting solutions. Membership functions for both objectives and constraints
are formulated to reflect uncertainties in different system components and their interrelationships. An interactive solution
procedure has been developed based on solution approaches of the interval-parameter and fuzzy programming techniques, plus
necessary measures for handling the multiobjective feature. A didactic example is provided in the paper to illustrate the
detailed solution process. Possibilities of further improvements by seeking Pareto optimum and incorporating flexible preference
within constraints are also discussed. 相似文献