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31.
The importance of particle X-ray microanalysis for contemporary metallurgical research has been accentuated. Corrections in the formulae for the geometric modelling method and simplifications in the calculation procedure are introduced. Conditions for successful application of the peak to background ratio method were outlined. Besides these two methods related to isolated particles a new extrapolation method for matrix embedded particles is developed and comments to the particle weight fraction estimation method for the same kind of particles are given.  相似文献   
32.
Novel light-emitting organic materials comprising conjugated oligomers chemically attached via a flexible spacer to an electron–or hole-conducting core were synthesized by Stille cross-coupling methodology and designed for tunable charge injection and optical properties. The hyperbranched structures have been characterized by 1H NMR, 13C NMR, and UV-VIS spectroscopy. The obtained structures show good stability in common organic solvents such as CHCl3, toluene, and CH2Cl2 and exhibit excellent thermal stability. A preliminary electroluminescence properties were also investigated. This class of materials will help to balance charge injection and transport and to spread out the charge recombination zone, thereby significantly improving the device efficiency and lifetime of unpolarized and polarized OLEDs.  相似文献   
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Journal of Thermal Analysis and Calorimetry - Tetragonal zirconia (3YSZ) and cermet nickel–tetragonal zirconia (Ni/3YSZ) were obtained by citric method. The porosity of samples was increased...  相似文献   
35.

The design and experimental results of the application of a renewable mercury film silver based electrode to the determination of Cr(VI) in soil samples are presented. The main feature of this procedure is that it can be used in field measurements. The procedure is based on the extraction of total Cr(VI) exploiting the complexation property of diethylenetriaminepentaacetic acid (DTPA) followed by electrochemical reduction of Cr(VI) to Cr(III) with the formation of Cr(III)-H2DTPA complex adsorbed on mercury film electrode. The voltammetric signal is caused by reduction of this complex. The validation of the proposed procedure was made by Cr(VI) determination in the certified reference material “Chromium VI in soil”. The protocol for Cr(VI) determination has also been applied to the analysis of Rendoll soil samples with satisfying precision.

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This paper is concerned with estimates of important factorization constants that appear in Banach space theory. We prove upper bounds of the Hilbertian norm of projections on finite-dimensional spaces of interpolation spaces generated by certain abstract interpolation functors and show applications to Calderón–Lozanovskii spaces. We also prove estimates of the p-factorization norm and projection constants for finite-dimensional Banach lattices. We show as a consequence of our results that in a large class of n-dimensional Banach sequence lattices \(E_n\) the projection constants \(\lambda (E_n)\) satisfy \(\lim _{n\rightarrow \infty }\lambda (E_n)/\sqrt{n} = c\), where \(c=\sqrt{2/\pi }\) in the real case and \(c= \sqrt{\pi }/2\) in the complex case. Applications are given to vector-valued sequence spaces.  相似文献   
38.
The main aim of this paper is to study a general multisublinear operators generated by quasi-concave functions between weighted Banach function lattices. These operators, in particular, generalize the Hardy–Littlewood and fractional maximal functions playing an important role in harmonic analysis. We prove that under some general geometrical assumptions on Banach function lattices two-weight weak type and also strong type estimates for these operators are true. To derive the main results of this paper we characterize the strong type estimate for a variant of multilinear averaging operators. As special cases we provide boundedness results for fractional maximal operators in concrete function spaces.  相似文献   
39.
We estimate Weyl numbers and eigenvalues of operators via studying their abstract summing norms. In particular we prove estimates of these summing norms for abstract interpolation Lorentz spaces. For this we combine factorization theorems with estimates of concavity constants. Finally we apply our general eigenvalue results to integral operators with kernels of weakly singular type. We obtain asymptotically optimal estimates which extend the well-known classical results.  相似文献   
40.
We study interpolation, generated by an abstract method of means, of bilinear operators between quasi-Banach spaces. It is shown that under suitable conditions on the type of these spaces and the boundedness of the classical convolution operator between the corresponding quasi-Banach sequence spaces, bilinear interpolation is possible. Applications to the classical real method spaces, Calderón-Lozanovsky spaces, and Lorentz-Zygmund spaces are presented. The author is supported by the National Science Foundation under grant DMS 0099881. The author is supported by KBN Grant 1 P03A 013 26.  相似文献   
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