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Julia Choina, Diana Dolat, Ewelina Kusiak, Magdalena Janus and Antoni Morawski

-3373(02)00269-2. Suda, Y., Kawasaki, H., Uea, T. & Ohshima, T. (2004). Preparation of high quality nitrogen doped TiO 2 thin film as a photocatalyst using a pulsed laser deposition method. Thin Solid Films. 453-454, 162-166. DOI: 10.1016/ j.tsf.2003.11.185. Tasbihi, M., Ngah C. R., Aziz, N., Mansor, A., Abdullah, A. Z., Teong, L. K. & Mohammed, A. R. (2007). Lifetime and Regeneration Studies of Various Supported TiO 2 Photocatalysts for the Degradation of Phenol under UV-C Light in a Batch Reactor. Ind. Eng. Chem. Res. 46(26), 9006-9014. DOI: 10

Open access

Melda Altikatoglu and Huriye Kuzu

Improvement of enzyme stability via non-covalent complex formation with dextran against temperature and storage lifetime

The optimal methodology to prepare the novel modified enzyme, polymer-enzyme complex, was developed to give a high catalytic activity in aqueous solution. The non-covalent complexes of two different enzymes (horseradish peroxidase and glucose oxidase) were prepared with various molar ratios (nD/nE 0,05; 0,1; 1; 5; 10; 15; 20) by using 75kDa dextran. The thermal stabilities of the obtained complexes were evaluated with the activities determined at different temperatures (25, 30, 35, 40, 50, 60, 70, 80°C) applying 60 minutes incubation time for pH 7. The complexes with the molar ratio nD/nHRP: 10 and nD/nGOD: 5 showed the highest thermal stability. Its activity was very high (ca. 1,5-fold higher activity than pure enzyme for HRP-dextran complexes) and almost the same between applying one hour incubation time and without incubation, and could also be measured at high temperatures (70, 80 °C). We finally succeeded in preparing dextran-enzyme complexes which showed higher activity than pure enzyme in aqueos solution at all temperatures for pH 7. In addition, the mentioned complexes at pH 7 had very long storage lifetime compared to purified enzyme at +4 °C; which is considered as a good feature for the usage in practice.

Open access

Jordan Hristov

. & Gwadera, M. (2012). On the application of an approximate kinetic equation of heat and mass transfer processes: the effect of body shape, Heat Mass Transfer , 48 (4), 599 -610. DOI: 10.1007/s00231-011-0905-6. 23. Rosner, D.E. (1969). Lifetime of a Highly Soluble Dense Spherical Particle1, The Journal of Physical Chemistry , 73 (2), 382-387. DOI: 10.1021/j100722a019. 24. Rice, R.G. & Do, D.D. (2006). Dissolution of a solid sphere in an unbounded, stagnant liquid, Chem. Eng. Sci ., 61 (2), 775-778. DOI: 10.1016/j.bbr.2011

Open access

Rafał Przekop and Leon Gradoń

Abstract

Deep bed filtration is an effective method of submicron and micron particle removal from the fluid stream. There is an extensive body of literature regarding particle deposition in filters, often using the classical continuum approach. However, the approach is not convenient for studying the influence of particle deposition on filter performance (filtration efficiency, pressure drop) when non-steady state boundary conditions have to be introduced. For the purposes of this work the lattice-Boltzmann model describes fluid dynamics, while the solid particle motion is modeled by the Brownian dynamics. For aggregates the effect of their structure on displacement is taken into account. The possibility of particles rebound from the surface of collector or reentrainment of deposits to fluid stream is calculated by energy balanced oscillatory model derived from adhesion theory. The results show the evolution of filtration efficiency and pressure drop of filters with different internal structure described by the size of pores. The size of resuspended aggregates and volume distribution of deposits in filter were also analyzed. The model enables prediction of dynamic filter behavior. It can be a very useful tool for designing filter structures which optimize maximum lifetime with the acceptable values of filtration efficiency and pressure drop.

Open access

E. Evin, M. Tomáš, J. Graban and M. Tóth

Abstract

Nowadays, number of customer and environmental requirements are laid to the automotive industry. These are related to safety increase, the weight and emission reduction as well as the life-time improvement. The article presents the way to improve the corrosion resistance of the car-body components when coated steel sheets are used based on Zn-Al-Mg coatings. Thus, the life-time of the car-body is improved. Samples with conventional Zn coating and samples with advanced Zn-Al-Mg coatings were deformed by stretching and 3-point bending to 90° and 180° tests. Consequently, the samples were exposed to salt spray in the corrosion chamber. Time to red corrosion appearance and adequate percentage of corroded surface was evaluated. The results showed the better corrosion protection of Zn-Al-Mg coatings when compared to the conventional Zn coating.

Open access

Jan Grzeszczak, Łukasz Grela and Thomas Achter

Abstract

The paper covers problems of the owners of a fleet of long-operated conventional power plants that are going to be decommissioned soon in result of failing to achieve new admissible emissions levels or exceeding pressure elements design lifetime. Energoprojekt-Katowice SA, Siemens AG and Rafako SA presents their joint concept of the solution which is a 2on1 concept - replacing two unit by two ultra-supercritical boilers feeding one turbine. Polish market has been taken as an example.

Open access

A. Kobzová, D. Kárník, Z. Skoumalová and P. Marcinský

LITERATURA 1. Boric Acid Corrosion Evaluation (BACE) program phase L-Task 1 report: Industry experience reference and available test data summary, 1993. 2. Timofeev B.: Assessment of the first generation RPV state after designed lifetime. International Journal of Pressure Vessels and Piping 2004 , 81, 703-712. 3. Jursík F.: Anorganická chemie nekovů. VŠCHT Praha, 2001. 4. Klikorka J., Hájek B., Votinský J.: Obecná a anorganická chemie. SNTL: Praha, 1989. 5. Kocakusak S., Köroglu H.J., Tolun R.: Drying of wet boric acid by

Open access

K. Kreislova, M. Jaglova, L. Turek and A. Koukalova

Investigation of Sampled OHTL Conductors and a Probabilistic Lifetime Estimation Method, Proceedings of 44th CIGRE Session, Paris (FRA), 2012.

Open access

J. Stoulil, M. Kouřil and D. Dobrev

REFERENCES 1. Björkbacka, Å., et al., Radiation induced corrosion of copper for spent nuclear fuel storage. Radiation Physics and Chemistry 2013 , 92, 80-86. 2. Björkbacka, Å., et al., Role of the Oxide Layer in Radiation-Induced Corrosion of Copper in Anoxic Water. The Journal of Physical Chemistry C 2016 , 120 (21), 11450-11455. 3. Bjorkbacka, A., et al., Kinetics and mechanisms of reactions between H 2 O 2 and copper and copper oxides. Dalton Trans 2015 , 44 (36), 16045-51. 4. King, F.; Kolar, M., Lifetime Predictions for

Open access

Jarosław Milewski, Łukasz Szabłowski and Wojciech Bujalski

.A., http://www.pgnig.pl/. [23] RWE Polska S.A., http://www.rwe.pl. [24] Hewalex Sp. z o.o. Sp.k., http://www.hewalex.pl/. [25] Fan J., Chen Z., Furbo S., Perers B., and Karlsson B.: Efficiency and lifetime of solar collectors for solar heating plants. In: Proc. ISES Solar World Congress 2009, 331-340, Johannesburg 2009. [26] Journal of Laws of the Republic of Poland (Dziennik Ustaw, Dz.U.) No. 75, item 690 of 12 Apr. 2002, as amended (in Polish).