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Radosław Zaleski, Kazimierz Zaleski and Marek Gorgol

, R. (2009). Badania warstwy wierzchniej stopu tytanu technikami wykorzystującymi anihilację pozytonów. Inżynieria Materiałowa , 5, 302–305. 7. Kansy, J. (1996). Microcomputer program for analysis of positron annihilation lifetime spectra. Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. , 374 (2), 235–244. DOI: 10.1016/0168-9002(96)00075-7. 8. Mengucci, P., Barucca, G., Riontino, G., Lussana, D., Massazza, M., Ferragut, R., & Aly, E. H. (2008). Structure evolution of a WE43 Mg alloy submitted to different thermal

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S.O. Pyskunov, Yu.V. Maksimyk and V.V. Valer

1 Introduction Structural elements of responsible objects function often under long-term static or cyclic force loading. The process of creep or fatigue, accompanied by the gradual accumulation of scattered damage, the formation and growth of macroscopic defects (fracture zones) are occurs under such a loading conditions. This problem, similarly as well as other aspects of reliability analysis [ 1 , 2 , 5 ], is very important for a reliable determination of long-term strength and lifetime. A description of above mentioned processes, which took the name

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Radosław Zaleski

. Rodriguez-Reinoso, & N. A. Seaton (Eds.), Characterisation of porous solids VIII: Proceedings of the 8th International Symposium on the Characterisation of Porous Solids (pp. 303–310). The Royal Society of Chemistry. 8. Kullmann, J., Enke, D., Thraenert, S., Krause-Rehberg, R., & Inayat, A. (2010). Characterization of nanoporous monoliths using nitrogen adsorption and positronium annihilation lifetime spectroscopy. Colloids Surf. A , 357 (1/3), 17–20. DOI: 10.1016/j.colsurfa.2009.09.030. 9. Zaleski, R., Stefaniak, W., Maciejewska, M., & Goworek, J. (2009

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Marek Gorgol, Bożena Jasińska and Renata Reisfeld

–407). Cambridge: RSC Publishing. DOI: 10.1039/9781847559418-00400. 5. Fischer, C. G., Weber, M. H., Wang, C. L., McNeil, S. P., & Lynn, K. (2005). Positronium in low temperature mesoporous films. Phys. Rev. B , 71 (18), 180102. DOI: 10.1103/PhysRevB.71.180102. 6. Śniegocka, M., Jasińska, B., Zaleski, R., & Goworek, T. (2006). Temperature dependence of o-Ps lifetime in some porous media. Deviation from ETE model. Chem. Phys. Lett ., 430 , 351–354. DOI: 10.1016/j.cplett.2006.09.001. 7. Thraenert, S., Hassan, E. M., Enke, D., Fuerst, D., & Krause-Rehberg, R

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Ewelina Kubicz, Bożena Jasińska, Bożena Zgardzińska, Tomasz Bednarski, Piotr Białas, Eryk Czerwiński, Aleksander Gajos, Marek Gorgol, Daria Kamińska, Łukasz Kapłon, Andrzej Kochanowski, Grzegorz Korcyl, Paweł Kowalski, Tomasz Kozik, Wojciech Krzemień, Szymon Niedźwiecki, Marek Pałka, Lech Raczyński, Zenon Rajfur, Zbigniew Rudy, Oleksandr Rundel, Neha Gupta Sharma, Michał Silarski, Artur Słomski, Adam Strzelecki, Anna Wieczorek, Wojciech Wiślicki, Marcin Zieliński and Paweł Moskal

References 1. Eldrup, M., Lightbody, D., & Sherwood, J. N. (1981). The temperature dependence of positron lifetimes in solid pivalic acid. Chem. Phys ., 63 , 51–58. DOI: 10.1016/0301-0104(81)80307-2. 2. Tao, S. (1972). Positronium annihilation in molecular substances. J. Chem. Phys ., 56 , 5499–5510. 3. Gidley, D. W., Frieze, W. E., Dull, T. L., Yee, A. F., Ryan, E. T., & Ho, H. -M. (1999). Positronium annihilation in mesoporous thin films. Phys. Rev. B , 60 , R5157(R). DOI: 10.1103/PhysRevB.60.R5157. 4. Goworek, T., Ciesielski, K

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Sanja Ćulubrk, Vesna Lojpur, Željka Antić and Miroslav D. Dramićanin

Abstract

Europium-doped yttrium oxide nanoparticles with different doping concentrations were prepared by self-propagation room temperature reaction method. This simple synthesis method provides particles in the range of 12nm to 50 nm, depending on the temperature of calcination. In all cases, the nanopowders showed intense red emission upon excitation with ultraviolet radiation. Structural and optical characterization showed that the nanoparticles obtained after calcination at 1100°C have smaller unit cell volume and microstrain and longer emission lifetimes compared to the nanoparticles obtained after calcination at 600°C and 800°C. The maximal emission intensity was found for the sample doped with 5at% of Eu3+.

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V. Đorđević, Ž. Antić, M. G. Nikolić and M. D. Dramićanin

Abstract

This work explores the influence of dopant concentration on photoluminescent emission and kinetics of Eu3+-doped (0.2−10 at.%) nanocrystalline lanthanumoxide powders. The X-ray diffraction analysis confirmed that all samples crystallize in La2O3 hexagonal phase with space group P3¯ m1. Transmission electron microscopy showed particles with non-uniform shape and diverse size distribution with an average particle size of (95 ± 5) nm. The room temperature photoluminescence spectra of all samples contain characteristic Eu3+ luminescence lines with the most pronounced red 5D0 7F2 emission at about 626 nm. The maximum intensity of red emission is observed for the sample containing 5at.% of Eu3+ ions. The emission kinetics was recorded in the temperature range from 10K to 300 K. The maximum lifetime value of 0.98 ms obtained for the sample with 0.5at.% Eu3+ at room temperature increases up to 1.3ms at 10 K.

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G. Lj. Majstorović and N. M. Šišović

, (Smirnov BM ed. Moscow: Energoatomizdat, 1984). [29] J. R¨opcke, M. Kaning and B. P. Lavrov, J. Phys. IV France 8, 207 (1998). [30] H. M. Crosswhite, The hydrogen molecule wavelength tables (Gerhard Heinrich Dieke. New York: Wiley-Interscience, 1972). [31] U. Fantz and D. Wnderlich, Franck-Condons Factors, Transition probabilities and radiative lifetimes for hydrogen molecules and their isotopomere ( INDC(NDS)-457 2004). [32] M. Osiac, B. P. Lavrov and J. R¨opcke, J. Q. S. R. T. 74, 471 (2002

Open access

JM Moore

Abstract

It is my distinct pleasure to make this presentation of the TSRC Lifetime Achievement Award to Dr Bill Collins from NC State University. Bill is well known in academic and industry circles for his contributions to Tobacco Science. Some have suggested that Bill Collins is the single person most identified with flue-cured tobacco at NC State and probably world-wide.

Open access

A Rodgman

References 1. Lifetime Achievement Award: Dr. Dietrich Hoffmann; 58 th Tobacco Science Research Conference, Program Booklet and Abstracts, Vol. 58, 2004, pp. 4–5. 2. Wright, G.F: Studies with tobacco smoke condensate; in : Proc. 3rd Natl. Cancer Conf., June, 1956, JB Lippincott Company (1957) 479–484. Wright, G.F and E.L. Wynder: Fractionation of cigarette tar; Proc. Am. Assoc. Cancer Res. 2(1) (1955) 5. Wright, G.F and E.L. Wynder: Further chemical studies of cigarette smoke condensate; Proc. Am. Assoc