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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

J. Vlček, D. Jančar, J. Burda, M. Klárová, M. Velička and P. Machovčák

Based on the operational measurement, of which content was to determine ladle thermal profile, there were analysed causes of possible damage of lining in steel ladles by steel breakout through the ladle shell. There exists connection between thermal state of ladle lining during the operation and its lifetime. There were reached to the conclusion that the cause of failure in the lining of ladle is except for high temperature of bath, also wide interval of temperature change during the tap operation, in consequence with possible insufficient pre-heating of ladle, discontinuous operation of aggregate and damage of insulating lining layer, respectively deformation of ladles shell.

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

P. Panek

Abstract

The influence of a p-type Si with different resistivity, charge carrier lifetime and emitter dopant impurities concentration on the crystalline silicon solar cells parameters were analyzed and experimentally checked. The findings were determined by quasi-steady-state photoconductance, current-voltage and spectral response methods. The study was accompanied by solar device simulation using a numerical PC1D program. The highest photoconversion efficiency of 15.13 % was obtained for the moncrystalline (Cz-Si) solar cell with a base resistivity of 1.8 Ωcm and an effective charge carrier lifetime of 22.9 μs. The results clearly confirmed the importance concerning the dopant level in a Si base material in relation to open circuit voltage and short circuit current possible to obtain from the solar cell. Reduction of a base material resistivtiy leads to a lower value of an effective charge carrier lifetime and photoconversion efficiency both for Cz-Si and multicrystalline (mc-Si) solar cells. The experimental results and calculation showed, that in the case of a solar cell produced on the basis of crystalline silicon, the most important spectral range for an efficiency of a cell is covering a wavelength range of 587 ÷ 838 nm.

Open access

Michał Kopacz

://web.cim.org/mes/pdf/valdaychrislattanzi.pdf Le Bel G., 1994. Determination of the Optimum Lifetime of a Mining Project Using Discounted Cash Flow and Option Pricing Techniques by B. Cavender-Discussion . Mining Engineering, 1994, access online on 15.03.2017: http://www.onemine.org/document/abstract.cfm?docid=6845&title=Discussion--Determination-Of-The-Optimum-Lifetime-Of-A-Mining-Project-Using-Discounted-Cash-Flow-And-Option-Pricing-Techniques--Cavender-B Li S., Knights P., Dunn D.J., 2008. Geological uncertainty and risk: implications for the viability of mining projects . Journal of Coal Science

Open access

Jacek Nowak and Magdalena Kokowska-Pawłowska

Sydney basin, Nova Scotia – elements sites, distribution, mineralogy . International Journal of Coal Geology 19, 219-251. Buda A., Jarynowski A., 2010. Life-time of correlations and its applications . vol. 1, Wydawnictwo Niezależne: 5-21, December 2010, ISBN 978-83-915272-9-0. Całus-Moszko J., Białecka B., 2013. Analiza możliwości pozyskania pierwiastków ziem rzadkich z węgli kamiennych i popiołów lotnych z elektrowni . Gospodarka Surowcami Mineralnymi – Mineral Resources Management 29, 1, 67-80. Castor B., Hedrick J.B., 2006. Rare Earth Elements

Open access

Zsolt Parapatits

gyógyítható betegségek. Budapest : Studium Bt., 2008. MICHAELIDES, E. E. 2016. A New Model for the Lifetime of Fossil Fuel Resources. In Natural Resources Research, 9. August 2016. NEW Scientist. 2012. Climate harms today’s economy. Retrieved: 2012. september 29. from: https://www.newscientist.com/ PÉK, T. 2013. A Mitől vagy Kitől változó klíma. Szülőföld Könyvkiadó, Szombathely. PERLMUTTER, D. D. – ROTHSTEIN, R. L. 2011. The Challenge of Climate Change: Which Way Now? Prospects After Copenhagen, ch. 11. John Wiley & Sons, Ltd., 2011, pp. 188

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

Seong Ho Son, Sung Cheol Park and Man Seung Lee

Abstract

In order to enhance the long-term stability of DSA for copper electroplating process, in the present study, noble metal oxides with excellent electrochemical properties was used and optimum condition was determined the ratio of noble metal oxides, surface pre-treatment of titanium substrate and heat treatment. The effect of the surface pretreatment of titanium substrate and ratio of noble metal oxides were estimated by accelerated test at the highly current density conditions. The lifetime of DSA increase six-fold higher as the oxide thickness of Ta 7 : Ir 3 composition ratio. Under the optimal condition, surface pretreatment led to dramatic increase in the lifetime of DSA.