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Salar Zohoori, Masoud Latifi, Abolfazl Davodiroknabadi and Mohammad Mirjalili

Abstract

Fabrication of electro-conductive fiber is a novel process. Nanocomposites of multiwall carbon nanotube/polyamide66 were produced by electrospinning with different amounts of multiwall carbon nanotube. Field emission scanning electron microscope and Fourier transform infrared spectroscopy of samples proved the existence of multiwall carbon nanotube distribution in polyamide 66 nanofibers. Results showed that electro conductivity of electrospun multiwall carbon nanotube/polyamide 66 nano fiber has increased in comparison with electrospun polyamide 66. Moreover, UV blocking of samples was investigated which has shown that using multiwall carbon nanotube in polyamide 66 increases UV blocking of fibers. Furthermore, anti-bacterial activity of nanocomposite showed that these nanocomposites have antibacterial property against both Staphylococcus Aureus and Escherichia Coli bacteria according to AATCC test method.

Open access

Bojidarka Koleva, Rositsa Nikolova, Atanas Tchapkanov, Tsonko Kolev, Heike Mayer-Figge, Michael Spiteller and William Sheldrick

Crystal structure and spectroscopic properties of 4-acetaminopyridine and its protonated form

4-Acetaminopyridine dihydrate and its protonated form, stabilized as the hydrochloride salt have been synthesized and spectroscopic elucidated in solution and in the solid-state by means of the inear-polarized solid state IR-spectroscopy (IR-LD), UV-spectroscopy, TGA, DSC, and the positive and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and the electronic spectra. The spectroscopic and theoretical data are compared with the structure of the first compound obtained by single crystal X-ray diffraction. The effect of Npy protonation on the optical and magnetic properties of a 4-acetaminopyridine is discussed.

Open access

Krzysztof Perkowski, Janusz Sokołowski and Mikołaj Szafran

Usability of high porosity ceramics for the separation of oily impurities

Organic impurities fallen to the ground water and to surface waters (rivers, lakes, seas and oceans) contribute to the degradation of the fauna and flora. Taking into account the public welfare, as the natural environment is, studies have been undertaken to develop a cheap and effective system for the purification of water from finely dispersed petroleum derivatives. The idea of the solution proposed consists in using a separator with high porosity ceramics of the pore size up to 100 ¨m, of high water permeability and ability to separate oily impurities of very tiny particle size. To improve the efficiency of the process the affinity of the filtering surface to organic particles was increased by the use of water-repellent media. The process of the separation of oily impurities was enhanced by means of ultrasounds of the 18 kHz frequency and various vibration energies.

Open access

Anna Steplewska, Roman Jedrzejewski and Ewa Borowiak-Palen

Preparation and characterization of catalyst mix Fe-Co/MgO for carbon nanotubes growth

Fe-Co/MgO is one of the most common catalyst mix applied to carbon nanotubes (CNTs) growth in chemical vapor deposition process. Therefore, here we present detailed study on the preparation and characterization of Fe-Co/MgO. The precursors of Fe and Co are iron (II) acetate and cobalt acetates, correspondingly. The molar ratio of the catalyst mix is Fe:Co:MgO=1:1:100. Initially, thermogravimetric analysis (TGA) of the mixture was performed. TGA analysis of it indicated the stepwise mass losses which pointed out the crucial thermal conditions for the changes in the elemental composition, morphology, crystallographic structure and vibrational properties. In current state of the art the lowest growth temperature for singlewalled carbon nanotubes is 550°C in CVD technique and here the characterization of the catalyst mix strongly suggest that this temperature can be decreased what would enhance the compatibility of CNT growth with current complementary metal-oxide-silicon (CMOS) technology for CNTs-based nanoelectronics. The morphology, crystallographic structure, elemental composition of the samples and its spectroscopic properties were performed via high resolution transmission electron microscopy (TEM), X-ray diffraction (XRD) and Infrared spectroscopy (IR), respectively.

Open access

Magdalena Janus, Beata Wawrzyniak, Beata Tryba and Antoni Morawski

Dye decomposition on P25 with enhanced adsorptivity

The preparation method and the activity of the TiO2-P25/N doped photocatalyst based on commercial titanium dioxide (TiO2 Aeroxide® P-25 Degussa, Germany) are presented. For the TiO2-P25/N preparation TiO2-P25 and gaseous ammonia were kept in a pressure reactor (10 bars) for 4 hours at the temperature of 200°C. This modification process changed the chemical structure of the TiO2 surface. The formation of NH4 + groups was confirmed by the FTIR measurements. Two bands in the range of ca. 1430 - 1440 cm-1 attributed to bending vibrations of NH4 + could be observed on the FTIR spectra of the catalysts modified with ammonia and the band attributed to the hydroxyl groups at 3300 - 3500 cm-1, which were not reduced after N-doping. The photocatalytic activity of the photocatalysts was checked through the decomposition of two dyes under visible light irradiation. The modified TiO2 thus prepared samples were more active than TiO2-P25 for the decomposition of dyes under visible light irradiation.

Open access

Magdalena Król, Kamila Brylewska, Arkadiusz Knapik, Kamil Kornaus and Włodzimierz Mozgawa

-based geopolymer. Appl. Clay Sci. 43(2), 218–223. DOI: 10.1016/j.clay.2008.09.003. 26. Mozgawa, W. (2007). Vibrational Spectroscopy of Zeolites. Habilitation dissertation, AGH University of Science and Technology, Krakow, Poland. 27. Rattanasak, U. & Chindaprasirt, P. (2009). Influence of NaOH solution on the synthesis of fly ash geopolymer. Miner. Eng. 22(12), 1073–1078. DOI: 10.1016/j.mineng.2009.03.022. 28. Heah, C.Y., Kamarudin, H., Mustafa Al Bakri, A.M., Bnhussain, M., Luqman, M. & Khairul Nizar, I. (2012). Study on solids-to-liquid and alkaline activator

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Piotr Michorczyk, Kamila Zeńczak, Rafał Niekurzak and Jan Ogonowski

. & Niemczyk, M. (2010). Investigation of catalytic activity of CrSBA-1 materials obtained by direct method in the dehydrogenation of propane with CO2, Appl. Catal. A: General , 374(1-2), 142-149. DOI: 10.1016/j. apcata.2009.11.040. 10. Morterra, C. & Magnacca, G. (1996). A case study: surface chemistry and surface structure of catalytic aluminas, as studied by vibrational spectroscopy of adsorbed species, Catal. Today 27(2-3), 497-532. 11. Lavalley, J. (1996). Infrared spectrometric studies of the surface basicity of metal oxides and

Open access

Kai Wang, Zixu Zhang, Qiong Liu, Xincheng Tu and Hyoung-Bum Kim

(11), 3868–3877. DOI: 10.1016/j.nucengdes.2010.09.004. 6. Mohr, U. & Gelbe, H. (2000). Velocity distribution and vibration excitation in tube bundle heat exchangers. Int. J. Therm. Sci . 39(3), 414–421. DOI: 10.1016/S1290-0729(00)00214-3. 7. Kim, M.I., Lee, Y., Kim B.W., Lee, D.H. & Song W.S. (2009). CFD modeling of shell-and-tube heat exchanger header for uniform distribution among tubes. Korean J. Chem. Enginee . 26(2), 359–363. DOI: 10.1007/s11814-009-0060-7. 8. Wang, K., Tu, X.C., Bae, C.H. & Kim, H.B. (2015). Optimal design of porous baffle to

Open access

Joanna Rymarczyk, Elżbieta Czerwosz, Mirosław Kozłowski, Piotr Dłużewski and Wojciech Kowalski

. Sensor Lett. 11, 500-504. DOI: 10.1166/sl.2013.2915. 11. Kuzmany, H. & Winter, J. (2000). Vibrational properties of fullerenes and fullerides. In W.Andreoni W. (ed) The Physics of Fullerene-Based and Fullerene-Related Materials (pp. 203-248). Springer Science+Business Media Dordrecht.. DOI: 10.1007/978-94-011-4038-6. 12. Vaez-Taghavi, H. & Hirata, A. (2012). Effective pre- -treatments of fullerenes to be sublimated for deposition of amorphous carbon films in electron beam excited plasma, Diamond & Related Materials 30, 9-14. DOI: 10

Open access

Zbigniew Krzysiak, Waldemar Samociuk, Grzegorz Bartnik, Krzysztof Plizga, Dariusz Dziki, Zdzisław Kaliniewicz, Aleksander Nieoczym, Aleksander Wyciszkiewicz and Tomasz Otto

reliability of the first daily diesel engine start-up during its operation in the vehicle. Eksploatacja i Niezawodność - Maintenance and Reliabilit 1(41), 4–10. 8. Jedliński, Ł., Caban, J., Krzywonos, L., Wierzbicki, S. &Brumerčík, F. (2015) Journal of Application of vibration signal in the diagnosis of IC engine valve clearance, Journal of Vibroenginee. 17(1) 175–181. 9. Bartnik, G., Pieniak, D., Niewczas, M., Niewczas, A. & Marciniak, A. (2016) Probabilistic model for flexural strength of dental composites used in modeling reliability of the “tooth