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51.
52.
Małgorzata Borówko Krzystof Stępniak Stefan Sokołowski Roman Zagórski 《Czechoslovak Journal of Physics》1999,49(7):1067-1075
The structure of liquid-gas interface of associating Lennard-Jones particles is studied using the density-functional theory
and the Monte Carlo simulation. The model with one bonding site per particle is considered. It is shown that the considered
version of the density functional is quite successful in predicting the gas-liquid density profile. 相似文献
53.
54.
A. A. Belov F. Firszt V. S. Gorelik A. L. Karuzskii E. I. Mahov H. Męczyńska A. V. Perestoronin P. P. Sverbil' J. Szatkowski 《Journal of Russian Laser Research》2003,24(1):14-26
Investigations of photoluminescence and Raman scattering in the ternary Zn1-xMgxSe compounds at 4.2 K were performed both in the Stokes and anti-Stokes regions using cw laser excitation with various wavelengths within the transparency band of the crystals. The anti-Stokes luminescence was observed for the first time in the ternary Zn1-xMgxSe compounds. We have found variations in the shape and position of the Stokes and anti-Stokes luminescence bands with an increase in the band gap energy, which depends on magnesium content. We assume that the anti-Stokes emission is generated by two-step excitation via deep-level centers. It is shown that the low-temperature anti-Stokes photoluminescence can probe the spatial distribution profiles of impurities in the bulk of crystals. 相似文献
55.
The investigation of microstructure and chemical composition of the and phases were performed in a Ni-base superalloy by means of analytical electron microscopy. The distribution of particular elements in the alloy was revealed using X-ray mapping in a transmission electron microscope. The detected concentration profiles of alloying elements at the / interface were relatively sharp in the case of cuboidal shape of the phase while they resembled the classical diffusion profile for the oval phase. The quantitative analysis of the phase revealed much higher content of Al and lower of Ti, W, Co and Mo in the oval precipitates compared to cuboidal ones. This result is attributed to the different solidification paths, which is eutectic for the cuboidal precipitates and peritectic for the oval precipitates. 相似文献
56.
S. Pietri P. H. Rega Zs. Podolyák A. Jungclaus M. Pfützner D. Rudolph A. B. Garnsworthy S. J. Steer R. Hoischen M. Górska J. Gerl H. J. Wollersheim I. Kojouharov H. Schaffner J. Grębosz F. Becker P. Bednarczyk L. Caceres P. Doornenbal H. Geissel A. Kelic N. Kurz F. Montes W. Prokopowicz T. Saito S. Tashenov E. Werner-Malento W. Gelletly 《The European physical journal. Special topics》2007,150(1):319-320
The RISING (Rare ISotope INvestigations at GSI) project constitutes a major
pan-european initiative to study nuclear structure in exotic nuclei.
A brief outline of the technical details specific to studies of isomeric decays
following relativistic projectile fragmentation reactions is presented. 相似文献
57.
Constructions introduced by Dirac for singular Lagrangians are extended and reinterpreted to cover cases when kernel distributions are either nonintegrable or of nonconstant rank, and constraint sets need not be closed. 相似文献
58.
Arūnas Jagminas Marija Kurtinaitienė Kęstutis Mažeika Ričardas Rotomskis Gediminas Niaura Algirdas Selskis 《Journal of nanoparticle research》2011,13(9):4133-4142
Developing of a simple method for the fabrication of superparamagnetic iron oxide nanoparticles (Nps) is still a challenge for materials scientists. This work reveals a way to fabricate especially stable ferrofluids from spherical Nps of magnetite using the co-precipitation method, for which a new (diglycolic acid) stabilizer was applied. The Nps of the average size of ~7.4–16.5 nm were characterized by means of high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), selective area electron diffraction (SAED), Raman, FTIR and Mössbauer spectroscopy. The stabilization effect of the diglycolic acid for the growth of superparamagnetic Nps growth was discussed on the basis of experimental results. 相似文献
59.
Jacek Achrem‐Achremowicz Elżbieta Kępczyńska Marek Żylewski Zbigniew Janeczko 《Biomedical chromatography : BMC》2010,24(3):261-267
A series of superlipophilic or highly lipophilic semisynthetic betulin derivatives was prepared and their relative lipophilicity was measured by reversed‐phase thin‐layer chromatography (RP‐TLC) at different pH values using 1,4‐dioxane–acetate buffer mixtures as mobile phases. Cholesterol, 17β‐estradiol and pure betulin were used as the reference compounds. Linear relationships were found between RM values and 1,4‐dioxane concentrations in the mobile phases. LogP values were also calculated with computer programs ACD/LogP (ChemSketch 11.0, Advanced Chemistry Development Inc.) and ClogP (Daylight Chemical Information Systems Inc.). The empirical and theoretical data were compared, and the RM0 values correlated well with logP. Two of the synthesized betulin derivatives are reported for the first time. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
60.
C. Stępniak 《Annals of the Institute of Statistical Mathematics》1987,39(1):563-573
Summary It is shown that in linear estimation both unbiased and biased, all unique (up to equivalence with respect to risk) locally
best estimators and their limits constitute a complete class. 相似文献