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Martin Vanek, Filip Mravec, Martin Szotkowski, Dana Byrtusova, Andrea Haronikova, Milan Certik, Volha Shapaval and Ivana Marova

. Carotenoids from Rhodotorula and Phaffia: yeasts of biotechnological importance. J Ind Microbiol Biotechnol 2009; 36:163-180. 5. Kandori H, Sasabe H, MimuroI M. Direct Determination of a Lifetime of the S2 State of Beta-Carotene by Femtosecond Time-Resolved Fluorescence Spectroscopy. J Am Chem Soc 1994; 116:2671-2672. 6. Xia S, Tan C, Zhang Y, Abbas S, Feng B, Zhang X, Qin F. Modulating effect of lipid bilayer–carotenoid interactions on the property of liposome encapsulation. Colloids and Surfaces B: Biointerfaces 2015; 128:172-180. 7. Schlee C, Miedl M

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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

Open access

R. Grunvalds, A. Ciekurs, J. Porins and A. Supe

Abstract

In the research, measurements of polarisation mode dispersion of two OPGWs (optical ground wire transmission lines), in total four fibres, have been carried out, and the expected lifetime of the infrastructure has been assessed on the basis of these measurements. The cables under consideration were installed in 1995 and 2011, respectively. Measurements have shown that polarisation mode dispersion values for cable installed in 1995 are four times higher than that for cable installed in 2011, which could mainly be explained by technological differences in fibre production and lower fibre polarisation mode dispersion requirements in 1995 due to lack of high-speed (over 10 Gbit/s) optical transmission systems. The calculation methodology of non-refusal work and refusal probabilities, using the measured polarisation mode dispersion parameters, is proposed in the paper. Based on reliability calculations, the expected lifetime is then predicted, showing that all measured fibres most likely will be operational within minimum theoretical service life of 25 years accepted by the industry.

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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

Open access

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

Open access

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

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

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+.

Open access

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.