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:209-215. 4. Błaszczyk T.: Analytical and numerical solution of the fractional Euler–Bernoulli beam equation . Journal of Mechanics of Materials and Structures 2017; 12:23:34. 5. Bobiński J., Tejchman J.. A coupled constitutive model for fracture in plain concrete based on continuum theory with non-local softening and eXtended Finite Element Method . Finite Elements in Analysis and Design 2016; 114:1-21. 6. Brinkgreve R.B.J.: Geomaterial models and numerical analysis of softening . PhD Thesis, TU Delft 1994. 7. Çağlar Y., Şener S.: Size effect tests of different notch

References [1] Onck P.R. (2002): Cosserat modeling of cellular solids . – C. R. Mechanique, vol.330, pp.717-722. [2] Chen C. and Fleck N.A. (2002): Size effects in the constrained deformation of metallic foams. – J. Mech. Phys. Solids, vol.50, pp.955-977. [3] Diebels S. and Steeb H. (2002): The size effect in foams and its theoretical and numerical investigation. – Proc. R. Soc. Lond. A 458, pp.2869-2883. [4] Donescu Şt., Munteanu L., Delsanto P.P. and Moşnegutu V. (2009): Chapter: On the advanced auxetic composites. – Research Trends in Mechanics, vol.3

Indentation Load-Size Effect in Al2O3 — SIC Nanocomposites

The indentation load-size effect (ISE) in Vickers hardness of Al2O3 and Al2O3 + SiC nanocomposites has been investigated and analysed using Meyer law, proportional specimen resistance (PSR) model and modified proportional specimen resistance (MPSR) model. The strongest ISE was found for alumina. Both the PSR and MPSR models described the ISE well, but the MPSR model resulted in slightly lower true hardness values for all materials investigated. No evidence of the effect of machining stresses on the ISE has been found.

References 1. Bažant Z.P. (1984), Size Effect in Blunt Fracture: Concrete, Rock, Metal, J. Eng. Mech., 110, 518-535. 2. Bažant Z.P. (1999), Size effect on structural strength: a review, Archive of Applied Mechanics, 69, 703-725. 3. Bodnar, A., Chrzanowski, M. (2002), On creep rupture of rectangular plates, ZAMM, 82, 201-205. 4. Carpinteri A., Spagnoli A. (2004), A fractal analysis of size effect on fatigue crack growth, Int. J. of Fatigue, 26, 125-133. 5. Carpinteri A., Spagnoli A., Vantadori S. (2002), An approach to size effect in fatigue of metals using

Abstract

NH4H2PO4 nano-composite antiferroelectric materials in porous glass have been studied by means of dielectric and dilatometric investigations. Dielectric spectroscopy measurements in a wide frequency range are reported here for the first time, for both the antiferro- and paraelectric phases of ammonium dihydrogen phosphate (ADP) embedded in a porous matrix. Low frequency relaxation processes above the phase transition temperature were shown to occur. An investigation of the thermal expansion revealed a negative volume jump at the phase transition point. It was found that the phase transition temperature in ADP crystals embedded in porous glass decreased with the decrease of the mean pore size. The experimentally observed shift of the phase transition temperature is caused by a combination of size and pressure effects.

2) plane. A Cd–S bond stretching has been identified by absorption peak at 651.62 cm –1 . Williamson-Hall (W-H) method has been employed to evaluate particle size (15.23 nm) and microstrain (6.93 × 10 -3 ). The particle size, analyzed using ImageJ programme is close to that obtained by W-H method. The lattice constants are found to be slightly less than bulk CdS values indicating lattice contraction. The existence of excitation peak and blue shift of fundamental absorption edge indicate quantum size effect in the CdS nanoparticles. These stable phase CdS

Regional Inequalities in the New European Union Member-States: Is There a ‘Population Size’ Effect?

and Banking Research , No. 1 (1), pp. 54–63. Blume, M. E., Stambaugh, R. F. (1983), Biases in computed returns: an application to the size effect, Journal of Financial Economics , Vol. 13, No. 3, pp. 387–404. Borys, M. M., Zemcik, P. (2009), Size and value effects in the Visegrad Countries, Emerging Markets Finance and Trade , Vol. 47, No. 3, pp. 50–68. Brown, P., Keim, D. B., Kleidon, A. W., Marsh, T. A. (1983), Stock return seasonalities and the tax-loss selling hypothesis: analysis of the arguments and Australian evidence, Journal of Financial Economics , Vol

Abstract

Multiwalled carbon nanotubes (MWCNTs) have attracted huge attention due to their multifunctionality. Their unique properties allows for covalent and noncovalent modifications. The most simple method for functionalization of carbon nanotubes is their decoration with the oxygen containing moieties which can be further simultaneously functionalized for design of new class carriers for targeting and imaging. Here, we present methodology for chopping nanotubes, characterization of MWCNTs, the effect of size on the biocompatibility in culture of L929 mouse fibroblasts using WST-1, LDH and apoptosis assays. The analysis provides the optimal carbon nanotubes length and concentration which can be used for functionalization in order to minimize the effect of the secondary agglomeration when interacting with cells.

Abstract

A continuous CO2 laser (10.6 µm wavelength) was adopted to investigate the influence of powder particle sizes on microstructural and morphological characteristics of laser claddings.

To study the potential of powder in controlling the incident laser energy, different average particle sizes of Ni-base powder were deposited on an austenitic stainless steel X3CrNi18-10 substrate. The energy value necessary to melt a mass m of powder was calculated. The results indicate that this energy decreases with particle sizes.

The claddings obtained with small particle sizes revealed a good morphological aspect and a low dilution of the cladding layer in the substrate, yet enough to create a very good metallurgical bond. The residual stress state was also influenced. Concerning modeling, we have elaborated residual stress model in the case of laser cladding by exploiting the response surface methodology (RSM), using a quadratic regression model. Combined effects of three laser cladding parameters on the residual stress is explored by a statistical analysis of variance (ANOVA). Results show that the residual stress is influenced principally by the power delivered by laser beam and by the scanning speed. It is also indicated that the size of powder particle is the dominant factor affecting the residual stress.