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Ewa Dryzek, Maciej Sarnek and Mirosław Wróbel

References 1. Gutierrez-Urrutia, I., & Raabe, D. (2012). Grain size effect on strain hardening in twinning-induced plasticity steels. Scripta Mater ., 66 , 992–996. DOI: 10.1016/j.scriptamat.2012.01.037. 2. Yakubtsov, I. A., Ariapour, A., & Perovic, D. D. (1999). Effect of nitrogen on stacking fault energy of f.c.c. iron-based alloys. Acta Mater ., 47 , 1271–1279. DOI: 10.1016/S1359-6454(98)00419-4. 3. Adler, P. H., Olson, G. B., & Owen, W. S. (1986). Strain hardening of hadfield manganese steel. Metall. Mater. Trans. A-Phys. Metal. Mater

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Zbigniew Surowiec, Marek Wiertel, Wojciech Gac and Mieczysław Budzyński

-Patkowska, A., & Zawadzki, W. (2012). Preparation, characterization and catalytic activity of palladium nanoparticles embedded in the mesoporous silica matrices. World J. Nano Sci. Eng. , 2 , 117–125. http://dx.doi.org/10.4236/wjnse.2012.23015 . 4. Sahoo, B., Sahu, S. K., Nayak, S., Dharaa, D., & Pramanik, P. (2012). Fabrication of magnetic mesoporous manganese ferrite nanocomposites as efficient catalyst for degradation of dye pollutants. Catal. Sci. Technol ., 2 , 1367–1374. DOI: 10.1039/c2cy20026k. 5. Kumar, C. S. S. R., & Mohammad, F. (2011). Magnetic

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Piotr Decyk, Andrzej B. Więckowski, Lidia Najder-Kozdrowska and Iveta Bilkova

References 1. Fierro, G., Morpurgo, S., Lo Jacono, M., Inversi, M., & Pettiti, I. (1998). Preparation, characterisation and catalytic activity of Cu-Zn-based manganites obtained from carbonate precursors. Appl. Catal. A-Gen ., 166 (2), 407–417. DOI: 10.1016/S0926-860X(97)00283-4. 2. Fei, J. H., Yang, M. X., Hou, Z. Y., & Zheng, X. M. (2004). Effect of the addition of manganese and zinc on the properties of copper-based catalyst for the synthesis of syngas to dimethyl ether. Energy Fuels , 18 (5), 1584–1587. DOI: 10.1021/ef049961f. 3. Fei, J

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Marek Wiertel, Zbigniew Surowiec, Mieczysław Budzyński and Wojciech Gac

Abstract

In this paper, results of positron annihilation lifetime spectroscopy (PALS) studies of MnFe2O4/MCM-41 nanocomposites in N2 and O2 atmosphere have been presented. In particular, the influence of manganese ferrite loading and gas filling on pick-off ortho-positronium (o-Ps) annihilation processes in the investigated samples was a point of interest. Disappearance of the longest-lived o-Ps component with τ5 present in the PAL spectrum of initial MCM-41 mesoporous material in the PAL spectra of MnFe2O4-impregnated MCM-41 measured in vacuum is a result of either a strong chemical o-Ps quenching or the Ps inhibition effects. The intensity I 4 of the medium-lived component initially increases, reaching a maximum value for the sample with minimum manganese ferrite content, and then decreases monotonically. Analogous dependence for the intensity I 3 of the shortest-lived component shows a maximum at higher MnFe2O4 content. Filling of open pores present in the studied nanocomposites by N2 or O2 at ambient pressure causes partial reappearance of the τ4 and τ5 components, except a sample with maximum ferrite content. The lifetimes of these components measured in O2 are shortened in comparison to that observed in N2 because of paramagnetic quenching. Anti-inhibition and anti-quenching effects of atmospheric gases observed in the MnFe2O4/MCM-41 samples are a result of neutralization of some surface active centers acting as inhibitors and weakening of pick-off annihilation mechanism, respectively.

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Agata Stoch, Jan Maurin, Paweł Stoch, Jan Kulawik and Dorota Szwagierczak

.1103/PhysRevB.70.132101. 6. Kulawik, J., & Szwagierczak, D. (2007). Dielectric properties of manganese and cobalt doped lead iron tantalate ceramics. J. Eur. Ceram. Soc., 27, 2281-2286. DOI: 10.1016/j.jeurceramsoc.2006.07.010. 7. Wang, J., Neaton, J. B., Zheng, H., Nagarajan, V., Ogale, S. B., Liu, B., Viehland, D., Vaithyanathan, V., Schlom, D. G., Waghmare, U. V., Spaldin, N. A., Rabe, K. M., Wuttig, M., & Ramesh, R. (2003). Epitaxial BiFeO3 multiferroic thin fi lm heterostructures. Science, 299, 1719-1722. DOI: 10.1126/science.1080615

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Amin Shahrokhi, Erika Nagy, Anita Csordás, János Somlai and Tibor Kovács

protection and safety of radiation sources: International basic safety standards. Vienna: IAEA. International Atomic Energy Agency 2014 Radiation protection and safety of radiation sources: International basic safety standards Vienna IAEA 5. Kávási, N., Somlai, J., Vigh, T., Tokonami, S., Ishikawa, T., Sorimachi, A., & Kovács, T. (2009). Difficulties in the dose estimate of workers originated from radon and radon progeny in a manganese mine. Radiat. Meas. , 44 , 300–305. 10.1016/j.radmeas.2009.03.014 . Kávási N. Somlai J. Vigh T

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Ali Khuder, Mohammad Adel Bakir, Reem Hasan, Ali Mohammad and Khozama Habil

analysis. Int. J. Phys. Sci., 6, 2090-2094. 26. Rao, K. S., Balaji, T., Rao, T. P., Babu, Y., & Naidu, G. R. K. (2002). Determination of iron, cobalt, nickel, manganese, zinc, copper, cadmium and lead in human hair by inductively coupled plasma atomic emission spectrometry. Spectroc. Acta Pt. B-Atom. Spectr., 57, 1333-1338. 27. Sturaro, A., Parvoli, G., Doretti, L., Zanchetta, S., & Allegri, G. (1993). Simultaneous determination of trace metals in human hair by dynamic ion-exchange chromatography. Anal. Chim. Acta, 274, 163

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Ilona Jastrzębska, Wiktor Bodnar, Kerstin Witte, Eberhard Burkel, Paweł Stoch and Jacek Szczerba

., Tao, G., & Li, Y. (2012). Composition and structure of a composite spinel made from magnesia and hercynite. J. Ceram. Proc. Res., 13(4), 480-485. 16. Gelbmann, G., Krischanitz, R., & Jörg, S. (2013). Hybrid spinel technology provides performance advances for basic cement rotary kiln bricks. RHI Bull., 2, 10-12. 17. Woodland, A. B., & Wood, B. J. (1990). The breakdown of hercynite at low fO2. Am. Miner., 75, 1342-1348. 18. Bromiley, G. D., Gatta, G. D., & Stokes, T. (2015). Manganese incorporation in synthetic hercynite