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Open access

Ziemowit M. Malecha and Karol Malecha

frequency side channel fluidic perturbations. Sens. Actuators B, 150, 811-818. DOI: 10.1016/j.snb.2010.08.027. Nguyen N.-T., 2012. Micromixers: Fundamentals, design and fabrication. 2nd edition, Elsevier, Oxford (UK). Nguyen N.-T., Wu Z., 2005. Micromixers - A review. J. Micromech. Microeng., 15, R1-R16. DOI: 10.1088/0960-1317/15/2/R01. Oberti S., Neild A., Wah Ng T., 2009. Microfluidic mixing under low frequency vibration. Lab Chip, 9, 1435-1438. DOI: 10.1039/b819739c. OpenFOAM, 2009. The Open Source CFD

Open access

Maciej Mikulski, Sławomir Wierzbicki and Andrzej Piętak

camelina oil esters on noise and vibration in a dual fuel CI engine. Diagnostyka, 15 (4), 53-57. Wierzbicki S., 2014. Laboratory control and measurement system of a dual-fuel compression ignition combustion engine operating in a cogeneration system. Solid State Phenomena. , 210, 200-205. DOI: 10.4028/www.scientific.net/SSP.210.200. Yan F., Wang J., 2011. Common Rail injection system iterative learning control based parameter calibration for accurate fuel injection quantity control. Int. J. Automot. Technol., 12, 149-157. DOI: 10.1007/s

Open access

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

Janusz T. Cieśliński and Tomasz Z. Kaczmarczyk

Abstract

The paper deals with pool boiling of water-Al2O3 and water- Cu nanofluids on rough and porous coated horizontal tubes. Commercially available stainless steel tubes having 10 mm outside diameter and 0.6 mm wall thickness were used to fabricate the test heater. The tube surface was roughed with emery paper 360 or polished with abrasive compound. Aluminium porous coatings of 0.15 mm thick with porosity of about 40% were produced by plasma spraying. The experiments were conducted under different absolute operating pressures, i.e., 200, 100, and 10 kPa. Nanoparticles were tested at the concentration of 0.01, 0.1, and 1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. It was observed that independent of operating pressure and roughness of the stainless steel tubes addition of even small amount of nanoparticles augments heat transfer in comparison to boiling of distilled water. Contrary to rough tubes boiling heat transfer coefficient of tested nanofluids on porous coated tubes was lower compared to that for distilled water while boiling on porous coated tubes. A correlation equation for prediction of the average heat transfer coefficient during boiling of nanofluids on smooth, rough and porous coated tubes is proposed. The correlation includes all tested variables in dimensionless form and is valid for low heat flux, i.e., below 100 kW/m2.

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

Sebastian Rulik, Leszek Remiorz and Sławomir Dykas

of the Acoustical Society of America 84 (1988), 4, 1148-1180. Hantschk C.C.: Vortmeyer D.: Numerical simulation of self-excited thermoacoustic instabilities in a Rijke tube. Journal of Sound and Vibration 277 (1999), 3, 511-522. Zoontjens L.: Numerical Investigations of the Performance and Effectiveness of Thermoacoustic Couples. PhD thesis, The University of Adelaide, Adelaide 2008. Zink F., Vipperman J., Schaefer L.: CFD simulation of thermoacoustic cooling. International

Open access

Yun-Yu Chen

characterized by UV second harmonic generation. In: Proc. Nat. Aca. Sci. USA PNAS 106(2009), 36, 15176-15180. [7] Li H., Li R., Zhu H.L. et al.: Influence of electrostatic field from soil particle surfaces on ion adsorption-diffusion. Soil Sci. Soc. Am. J. 74(2010), 4, 1129-1138. [8] Eftekharibafrooei A., Borguet E.: Effect of electric fields on the ultrafast vibrational relaxation of water at a charged solid-liquid interface as probed by vibrational sum frequency generation. J. Phys. Chem. Lett. 2(2011), 12, 1353-1358. [9