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Study of Cigarette Smoke Filtration by Means of the Scanning Electron Microscope


The method developed by Peck (8) for observing smoke deposits on cigarette filters with the scanning electron microscope was extended to two techniques to determine how the particulate phase of smoke is deposited on celluIose acetate filters and on individual cellulose acetate fibers.

Technique A: Immediately after the smoke particles were deposited on the fibers, the filter was exposed to methyl 2-cyanoacrylate vapour; the methyl 2 cyanoacrylate monomer polymerized rapidly and formed a very thin film (0.05 µ thick) over the partially volatile particles so they could be examined in the vacuum chamber of the scanning electron microscope. This technique was used to observe smoke deposits on single fibers oriented either parallel or perpendicularly to the smoke stream.

Technique B: Methyl 2-cyanoacrylate vapour was drawn into a mixing chamber in front of the filter as each puff of smoke was taken. The monomer coated the particles and polymerized. The coated particles were subsequently trapped by the fibers and observed with the scanning electron microscope.

From techniques A and B, it was observed that single fibers oriented parallel to the smoke stream showed a heavy deposition of small particles (<< 0.1 µ in diameter). This observation qualitatively confirms the theory that diffusion is one of the predominant mechanisms of filtration. Relatively smalI numbers of large smoke particles (> 0.5 µ in diameter) were trapped by single fibers oriented perpendicularly to the smoke stream. These large particles were trapped by interception on fibers which were perpendicular to the smoke path. The edge of each Y-cross-section fiber, where interception is most likely to occur, was more heavily coated than other parts of the fiber. All of the large particles in a 28- × 45-µ area on a single fiber oriented perpendicularly to the smoke stream were counted. The total number of particles on the fiber were calculated and compared to the amount expected from the totaI number of particles per puff, the fraction of particles larger than 0.5 µ, and the single fiber efficiency. Good agreement between the experimental and calculated values was obtained.

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Application of the reduced I-V Blaesser’s characteristics in predicting PV modules and cells conversion efficiency in medium and high insolation conditions

. Technical Digest of the PVSEC 15. Shanghai, 2005:422-423. . [12] King DL, Kratochvil JA, Boyson WE. Temperature coefficients for PV modules and arrays. Measurement methods, difficulties, and results. Proc 26 th IEEE PVSC. Anaheim: 1997. DOI: 10.1109/PVSC.1997.654300. [13] Virtuani A, Pavanello D, Friesen G. Overview of temperature coefficients of different thin film photovoltaic technologies. Proc 25 th EU PVSEC. Valencia: 2010:4248-4252. https

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The Use of Two-Diode Substitute Model in Predicting the Efficiency of PV Conversion in Low Solar Conditions

Photovoltaic Current-Voltage Characteristics. Geneva: IEC; 1987. [30] Blaesser G. PV array Data Translation Procedure. Proc. 13th EU PVSEC. Nice: 1995. [31] Marion B, Rummel S, Anderber A. Current-voltage translation by bilinear interpolation. Progress in Photovoltaics. 2004;12:593-607. DOI: 10.1002/pip.551. [32] Virtuani A, Pavanello D, Friesen G. Overview of Temperature Coefficients of Different Thin Film Photovoltaic Technologies. Proc. 25th EU PVSEC. Valencia: 2010

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A Low-Cost System for Measuring ppb-Level NO2

References 1. Baron, M.G., R. Narayanaswamy, and S.C. Thorpe: Luminescent porphyrin thin films for NO x sensing; Sensors and Actuators B11 (1993) 195–199. 2. Furuki, M., K. Ageishi, S. Kim, I. Ando, and L.S. Pu: Highly sensitive NO 2 optical detector with squarylium dye Langmuir-Blodgett film containing J aggregate; Thin Solid Films 180 (1989) 193–198. 3. Nakano, N.: Development of a monitoring tape for nitrogen dioxide in air; Anal. Chim. Acta 321 (1996) 41

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Effectiveness of Removal of Humic Substances and Heavy Metals from Landfill Leachates During their Pretreatment Process in the SBR Reactor

. Wenzel A, Gahr A, Niessner R. TOC-removal and degradation of pollutants in the leachate using a thin-film photoreactor. Water Res. 1999;33:937-946. Monje-Ramirez I, Orta de Velasquez MT. Removal and transformation of recalcitrant organic matter from stabilized saline landfill leachates by coagulation-ozonation coupling processes. Water Res. 2004;38:2358-2366. Ketchum LH. Design and physical features of sequencing bath reactors. Water Sci Techn. 1997;35:11-18. Grabińska-Łoniewska A

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The Thermodynamics of Tobacco-Water Interactions

thermal conductivity and contact resistance of paper and thin-film materials; Rev. Sci. Inst. 54 (1983) 238-244. 5. Brock, B.A. and M. Samfield: The heat capacity of tobacco - Part I; Tob. Sci. 2 (1958) 41-44. 6. CRC Handbook of Chemistry and Physics, 54 th Edition, edited by R. C. Weast, CRC Press, Cleve-land, Ohio, 1973-1974, pp. Fil, D137, E26. 7. Zorbalas, D. I.: Uber die Wasserdesorption des Tabaks; Beitr. Tabakforsch. 4 (1968) 85-89. 8. Jadraque, D. and A. R

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Critical thickness of foam films stabilized by nonionic, ionic surfactants and their mixtures

., Scheludko A., Manev E., Critical thickness of thin liquid films. Theory and experiment, J. Colloid Interface Sci., 1983, 95, 254-265. [7] Coons J., Halley P., Mc Glashan S. A. and Tran-Cong, T., Scaling laws for the critical rupture thickness of common thin films, Colloids and Surfaces A: 2005, 263, 258-266. [8] Ivanova D. S., Angarska J. K., Manev E. D., Determination of the critical thickness of thin liquid film based on a video record of its thinning, Conference proceedings “40 years -Shumen University” 2012, 342-351. [9

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A new system for measuring electrical conductivity of water as a function of admittance

Capillary Electrophoresis Devices. Anal. Chem. 2003; 75, 306-312. 12553766 10.1021/ac0157371 Laugere Frederic M. Guijt Rosanne Bastemeijer Jeroen van der Steen Gert Berthold Axel Baltussen Erik Sarro Pascalina W. K. van Dedem Gijs Vellekoop Michiel Bossche Andre On-Chip Contactless Four-Electrode Conductivity Detection for Capillary Electrophoresis Devices Anal. Chem 2003 75 306 312 9 Jinsong Yu and Chung-Chiun Liu, Microfabricated Thin Film Impedance Sensor

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Elemental composition of surface soils in Nature Park Shumen Plateau and Shumen City, Bulgaria

analysis of tree leaves by total reflection X-ray fluorescence: New approaches for air quality monitoring, Chemosphere , 2017 , 178 :504-512. [13]. Jia, Z.; Li, S.; Wang, L., Assessment of soil heavy metals for eco-environment and human health in a rapidly urbanization area of the upper Yangtze Basin, Scientific Reports , 2018 , 8 :3256. doi:10.1038/s41598-018-21569-6 [14]. Moriyama, T.; Morikawa, A.; Doi, M.; Fess, S., Aerosol filter analysis using polarized optics EDXRF with thin-film FP method

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Transient bioimpedance monitoring of mechanotransduction in artificial tissue during indentation

includes the microfluidic system and support, can be given as: (20) R s u b = ρ s u b L K k h s K k ′ h s $${{R}_{sub}}=\frac{{{\rho }_{sub}}}{L}\frac{K\left( {{k}_{hs}} \right)}{K\left( {{{{k}'}}_{hs}} \right)}$$ In a similar manner the geometry of the thin film of the conductive medium can be mapped onto the parallel plate geometry [ 36 ]. In this instance: (21) k t f = tanh π g 2 h tanh π s + g 2 h $${{k}_{tf}}=\frac{\tanh \left( \frac{\pi g}{2h} \right)}{\tanh \left( \frac{\pi \left( s+g \right)}{2h} \right)}$$ and: (22

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