The Crucial Role Of Molecular Ions In The Radial Contraction Of Argon Microwave-sustained Plasma Jets At Atmospheric Pressure

Fourteen ions (Ar+, Ar2+, ArH+, H2O +, H+(H2O), H+(H2O) 2, O+, O2+, OH+, NO+, N2+, N +, Ar2+, N4+) were detected, by mass-resolved ion-energy measurements when the discharge was operated at 50 W and fluxes of 2.5 and 5.0 slm. The crucial role of three molecular ions (Ar2+, ArH+, H2O +) during the radial contraction, from diffuse (r = (750 ± 50) μm) to contracted plasma jet (r = (500 ± 50) μm), and the relationship between power, gas flow and molecular ions production were pointed out. Ion energy distributions for Ar2+, ArH+ and H2O + exhibit their maxima at high-energies due to low-energy threshold for three-body collision reactions. © 2014 Elsevier B.V. All rights reserved.595-5968386Moisan, M., Zakrzewski, Z., (1991) J. Phys. D Appl. Phys., 24, p. 1025Jankowski, K., Reszke, E., (2013) J. Anal. At. Spectrom., 28, p. 1196Kudela, J., Odrobina, I., Kando, M., (1998) Jpn. J. Appl. Phys., 37, p. 4169Cahng, J.-S., (2001) Sci. Technol. Adv. Mater., 2, p. 571Levaton, J., Ricard, A., Henriques, J., Silva, H.R.T., Amorim, J., (2006) J. Phys. D Appl. Phys., 39, p. 3285Purevdorj, D., Igura, N., Ariyada, O., Hayakawa, I., (2002) Lett. Appl. Microbiol., 37, p. 1008Golubovskii, Y.B., Nekuchaev, V., Gorchakov, S., Uhrlandt, D., (2011) Plasma Sources Sci. Technol., 20, p. 053002Kenty, C., (1962) Phys. Rev. e, 126, p. 1235Massey, J.T., (1965) J. Appl. Phys., 36, p. 373Kabouzi, Y., Calzada, M.D., Moisan, M., Tran, K.C., Trassy, C., (1965) J. Appl. Phys., 91, p. 361Varey, R.H., Smalley, J., Richards, P.H., Gozna, C.F., Swift-Hook, D.T., (1971) J. Phys. D Appl. Phys., 4, p. 1520Daniels, P.G., Franklin, R.N., Snell, J., (1990) J. Phys. D Appl. Phys., 23, p. 823Yu Baranov, V., Ul'Yanov, K.N., (1969) Sov. Phys. Tech. Phys., 14, p. 176Golubovskii, Y.B., Sonneburg, R., (1979) Sov. Phys. Tech. Phys., 24, p. 173Golubovskii, Y.B., Sonneburg, R., (1979) Sov. Phys. Tech. Phys., 24, p. 177Golubovskii, Yu.B., Lange, H., Maiorov, V.A., Porokhova, I.A., Sushkov, V.P., (2003) J Phys. D, 36, p. 694Petrov, G.M., Ferreira, C.M., (1999) Phys. Rev. e, 59, p. 3571Castanos-Martínez, E., Moisan, M., (2011) IEEE Trans. Plasma Sci., 39, p. 2192Lukác, P., Mikus, O., Morva, I., Zábudlá, J., Trnovec, Z., Morvová, M., (2011) Plasma Sources Sci. Technol., 20, p. 055012Castanos-Martínez, E., Moisan, M., Kabouzi, Y., (2009) J. Phys. D Appl. Phys., 42, p. 012003Ridenti, M.A., Souza-Corrêa, J.A., Amorim, J., (2014) J. Phys. D Appl. Phys., 47, p. 045204Benedikt, J., Hecimovic, A., Ellerweg, D., Von Keudell, A., (2012) J. Phys. D Appl. Phys., 45, p. 403001Bruggeman, P., Iza, F., Lauwers, D., Gonzalvo, Y.A., (2010) J. Phys. D Appl. Phys, 43, p. 012003Hamers, E.A.G., Van Sark, W.G.J.H.M., Bezemer, J., Goeddheer, W.J., Van De Weg, W.F., (2010) Int. J. Mass Spectrom. Ion Process., 43, p. 012003Lukác, P., Mikus, O., Morva, I., Zábudlá, Z., Trnovec, J., Morvová, M., (2011) Plasma Sources Sci. Technol., 20, p. 055012Massey, J.T., Cannon, S.M., (1965) J. Appl. Phys., 36, p. 361Castanos-Martínez, E., Kabouzi, Y., Makasheva, K., Moisan, M., (2004) Phys. Rev. e, 70, p. 066405Amorim, J., Oliveira, C., Souza-Corrêa, J.A., Ridenti, M.A., (2013) Plasma Process. Polym., 10, p. 670Bundaleska, N., Tatarova, E., Dias, F.M., Lino Da Silva, M., Ferreira, C.M., Amorim, J., (2014) J. Phys. D Appl. Phys., 47, p. 05520

Experimental Study Of Unconfined Surface Wave Discharges At Atmospheric Pressure By Optical Emission Spectroscopy

A surface wave discharge (SWD) in argon at atmospheric pressure generated by a surfatron device was studied by optical emission spectroscopy (OES). Two distinct situations were investigated; (i) a discharge plasma in open air and (ii) a discharge plasma totally confined in a quartz tube. The electron density ne, electron temperature Te and gas temperature T g were investigated as a function of applied power and gas flow rate. The self-absorbing method was used to estimate the population of the metastable state Ar(1s5). These physical quantities were determined through optical measurements along the plasma axis of symmetry. The profile of the electron density presented a maximum value under certain conditions, in contrast with typical electron density profiles of SWDs which are usually monotonically decreasing. A correlation between the electron density and the metastable state Ar(1s5) was found in one of these cases, suggesting that stepwise ionization from metastable states and non-local kinetics play an important role on the unexpected increase in ionization degree along the discharge. © 2014 IOP Publishing Ltd.474Moisan, M., Zakrzewski, Z., Plasma sources based on the propagation of electromagnetic surface waves (1991) J. Phys. D: Appl. Phys., 24 (7), p. 1025. , 10.1088/0022-3727/24/7/001 0022-3727 001Trivelpiece, A.W., Gould, R.W., Space charge waves in cylindrical plasma columns (1959) J. Appl. Phys., 30, pp. 1784-1793. , 10.1063/1.1735056Moisan, M., Beaudry, C., Leprince, P., A small microwave plasma source for long column production without magnetic field (1975) IEEE Trans. Plasma Sci., 3, pp. 55-59. , 10.1109/TPS.1975.4316875 0093-3813Tatarova, E., Zamfirov, D., A radially resolved experimental investigation of the electron energy distribution function in a microwave discharge sustained by propagating surface waves (1995) J. Phys. D: Appl. Phys., 28 (7), p. 1354. , 10.1088/0022-3727/28/7/012 0022-3727 012Grosse, S., Schlüter, H., Tatarova, E., Axial dependence of the electron energy distribution function in microwave discharges sustained by propagating surface waves (1994) Phys. Scr., 50 (5), p. 532. , 10.1088/0031-8949/50/5/013 1402-4896 013Tatarova, E., Dias, F.M., Ferreira, C.M., Ricard, A., On the axial structure of a nitrogen surface wave sustained discharge: Theory and experiment (1999) Journal of Applied Physics, 85 (1), pp. 49-62Ivanova, K., Koleva, I., Shivarova, A., Optical spectroscopy diagnostics of a helium surface wave sustained discharge: I. Experiment (1995) Plasma Sources Sci. Technol., 4 (3), p. 444. , 10.1088/0963-0252/4/3/014 0963-0252 014Boisse-Laporte, C., Granier, A., Dervisevic, E., Leprince, P., Marec, J., Microwave discharges produced by surface waves in argon gas (1987) J. Phys. D: Appl. Phys., 20 (2), p. 197. , 10.1088/0022-3727/20/2/008 0022-3727 008Daviaud, S., Boisse-Laporte, C., Leprince, P., Marec, J., Description of a surface-wave-produced microwave discharge in helium at low pressure in the presence of a gas flow (1989) J. Phys. D: Appl. Phys., 22 (6), p. 770. , 10.1088/0022-3727/22/6/009 0022-3727 009Granier, A., Gousset, G., Leprince, P., Marec, J., Argon surface wave discharges at medium pressure. Experiments and discussion on the energy balance (1987) Rev. Phys. Appl., 22 (9), p. 999. , 10.1051/rphysap:01987002209099900 0035-1687Levaton, J., Ricard, A., Henriques, J., Silva, H.R.T., Amorim, J., Measurements of N(4S) absolute density in a 2.45 GHz surface wave discharge by optical emission spectroscopy (2006) J. Phys. D: Appl. Phys., 39 (15), p. 3285. , 10.1088/0022-3727/39/15/010 0022-3727 010Sismanoglu, B.N., Amorim, J., Souza-Corra, J.A., Oliveira, C., Gomes, M.P., Optical emission spectroscopy diagnostics of an atmospheric pressure direct current microplasma jet (2009) Spectrochim. Acta, 64, pp. 1287-1293. , 10.1016/j.sab.2009.10.006 0584-8547 BSouza-Corrêa, J.A., Oliveira, C., Gomes, M.P., Amorim, J., Electric and spectroscopic properties of argon-hydrogen rf microplasma jets at atmospheric pressure (2010) J. Phys. D: Appl. Phys., 43 (39). , 10.1088/0022-3727/43/39/395203 0022-3727 395203Santiago, I., Christova, M., Garcia, M.C., Calzada, M.D., Self-absorbing method to measure the population of the metastable levels in an argon microwave plasma at atmospheric pressure (2004) EPJ Applied Physics, 28 (3), pp. 325-330. , DOI 10.1051/epjap:2004194Calzada, M.D., Moisan, M., Gamero, A., Sola, A., Experimental investigation and characterization of the departure from local thermodynamic equilibrium along a surface-wave-sustained discharge at atmospheric pressure (1996) Journal of Applied Physics, 80 (1), pp. 46-55Van Gessel, A.F.H., Carbone, E.A.D., Bruggeman, P.J., Van Der Mullen, J.J.A.M., Laser scattering on an atmospheric pressure plasma jet: Disentangling Rayleigh, Raman and Thomson scattering (2012) Plasma Sources Sci. Technol., 21 (1). , 10.1088/0963-0252/21/1/015003 0963-0252 015003Palomares, J.M., Iordanova, E.I., Gamero, A., Sola, A., Mullen, J.J.A.M.V.D., Atmospheric microwave-induced plasmas in Ar/H2 mixtures studied with a combination of passive and active spectroscopic methods (2010) J. Phys. D: Appl. Phys., 43 (39). , 10.1088/0022-3727/43/39/395202 0022-3727 395202Carbone, E.A.D., Hübner, S., Jimenez-Diaz, M., Palomares, J.M., Iordanova, E., Graef, W.A.A.D., Gamero, A., Van Der Mullen, J.J.A.M., Experimental investigation of the electron energy distribution function (EEDF) by thomson scattering and optical emission spectroscopy (2012) J. Phys. D: Appl. Phys., 45 (47). , 10.1088/0022-3727/45/47/475202 0022-3727 475202Ridenti, M.A., Souza-Corrêa, J.A., Amorim, J., Study of neutral mass and positive ion energy distributions from atmospheric pressure surfatron Ar plasmas (2011) 30th ICPIG Conf. Proc.Fridman, A., Chirokov, A., Gutsol, A., Non-thermal atmospheric pressure discharges (2005) Journal of Physics D: Applied Physics, 38 (2), pp. R1-R24. , DOI 10.1088/0022-3727/38/2/R01Nagai, J., Thomaz, J.C., Amorim, J., Baravian, G., Experimental evidence of Penning ionization role in a low pressure direct current nitrogen glow discharge (2004) Eur. Phys. J. Appl. Phys., 26, pp. 53-58. , 10.1051/epjap:2004020Sola, A., Calzada, M.D., Gamero, A., On the use of the line-to-continuum intensity ratio for determining the electron temperature in a high-pressure argon surface-microwave discharge (1995) J. Phys. D: Appl. Phys., 28 (6), p. 1099. , 10.1088/0022-3727/28/6/012 0022-3727 012Muñoz, J., Calzada, M.D., Experimental research on surface wave Ar-He discharges at atmospheric pressure (2008) J. Phys. D: Appl. Phys., 41 (13). , 10.1088/0022-3727/41/13/135203 0022-3727 135203Souza-Corrêa, J.A., Oliveira, C., Wolf, L.D., Nascimento, V.N., Rocha, G.J.M., Amorim, J., Atmospheric pressure plasma pretreatment of sugarcane bagasse: The influence of moisture in the ozonation process (2013) Appl. Biochem. Biotechnol., 171, pp. 104-116. , 10.1007/s12010-013-0362-4 0273-2289Souza-Corrêa, J.A., Ridenti, M.A., Oliveira, C., Araújo, S.R., Amorim, J., Decomposition of lignin from sugar cane bagasse during ozonation process monitored by optical and mass spectrometries (2013) J. Phys. Chem., 117, pp. 3110-3119. , 10.1021/jp3121879 1089-5647 BAmorim, J., Oliveira, C., Souza-Corra, J.A., Ridenti, M.A., Treatment of sugarcane bagasse lignin employing atmospheric pressure microplasma jet in argon (2013) Plasma Process. Polym., 10, pp. 670-678. , 10.1002/ppap.201200158 1612-8850Moisan, M., Zakrzewskit, Z., Pantel, R., The theory and characteristics of an efficient surface wave launcher (surfatron) producing long plasma columns (1979) J. Phys. D: Appl. Phys., 12 (2), pp. 219-238. , 10.1088/0022-3727/12/2/008 0022-3727 008Mariotti, D., Shimizu, Y., Sasaki, T., Koshizaki, N., Method to determine argon metastable number density and plasma electron temperature from spectral emission originating from four 4p argon levels (2006) Applied Physics Letters, 89 (20), p. 201502. , DOI 10.1063/1.2390631Bartschat, K., Zeman, V., Electron-impact excitation from the (3p54s) metastable states of argon (1999) Phys. Rev., 59, pp. 2552-R2554. , 10.1103/PhysRevA.59.R2552 ABruggeman, P., Schram, D.C., Kong, M.G., Leys, C., Is the rotational temperature of OH(AX) for discharges in and in contact with liquids a good diagnostic for determining the gas temperature? (2009) Plasma Process. Polym., 6, pp. 751-762. , 10.1002/ppap.200950014 1612-8850Dieke, G.H., Crosswhite, H.M., The ultraviolet bands of OH fundamental data (1962) J. Quant. Spectrosc. Radiat. Transfer, 2, pp. 97-199. , 10.1016/0022-4073(62)90061-4 0022-4073Abrarov, S.M., Quine, B.M., Efficient algorithmic implementation of the voigt/complex error function based on exponential series approximation (2011) Appl. Math. Comput., 218, pp. 1894-1902. , 10.1016/j.amc.2011.06.072Gigosos, M.A., Cardeñoso, V., New plasma diagnosis tables of hydrogen stark broadening including ion dynamics (1996) J. Phys. B: At. Mol. Opt. Phys., 29 (20), p. 4795. , 10.1088/0953-4075/29/20/029 0953-4075 029Jolly, J., Touzeau, M., Measurement of metastable-state densities by self-absorption technique (1975) J. Quant. Spectrosc. Radiat. Transfer, 15, pp. 863-872. , 10.1016/0022-4073(75)90098-9 0022-4073Casta Nos Martínez, E., Moisan, M., Absorption spectroscopy measurements of resonant and metastable atom densities in atmospheric-pressure discharges using a low-pressure lamp as a spectral-line source and comparison with a collisional-radiative model (2010) Spectrochim. Acta, 65, pp. 199-209. , 10.1016/j.sab.2009.12.003 0584-8547 BMoisan, M., Pelletier, J., (2006) Physique des Plasmas Collisionnels: Application Aux Dcharges Haute FrquenceCarbone, E.A.D., Hübner, S., Palomares, J.M., Van Der Mullen, J.J.A.M., The radial contraction of argon microwave plasmas studied by Thomson scattering (2012) J. Phys. D: Appl. 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Thermodynamics of Combustion and Ideal Plasmas

<p></p><p>Abstract In this work we present the thermochemistry of combustion and ideal plasmas, illustrating it with some examples related to pollutants production in engines and plasma physics. We first define the problem and then present two different but equivalent strategies to solve it: (i) determination of a complete set of chemical reactions, its equilibrium constants and balance equations; (ii) minimization of the Gibbs free energy of the system. Some examples are solved using the code CEA - Chemical Equilibrium with Application developed by NASA, which is available on the web. In one of them the adiabatic temperature and the final chemical composition of decane (C10H22 combustion is determined. In another one we explored the problem of an ideal plasma composed of He and H2O. We also present the general problem of the time development of the chemical composition in a reactive medium. This is illustrated solving the Zeldovich-Keck mechanism for the formation of NO and applying it to the problem of pollution produced by internal combustion engines. These examples may inspire teaching activities in graduation and post graduation courses in Physics and Engineering.</p><p></p

Decomposition Of Lignin From Sugar Cane Bagasse During Ozonation Process Monitored By Optical And Mass Spectrometries

Mass spectrometry was used to monitor neutral chemical species from sugar cane bagasse that could volatilize during the bagasse ozonation process. Lignin fragments and some radicals liberated by direct ozone reaction with the biomass structure were detected. Ozone density was monitored during the ozonation by optical absorption spectroscopy. The optical results indicated that the ozone interaction with the bagasse material was better for bagasse particle sizes less than or equal to 0.5 mm. Both techniques have shown that the best condition for the ozone diffusion in the bagasse was at 50% of its moisture content. In addition, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed to analyze the lignin bond disruptions and morphology changes of the bagasse surface that occurred due to the ozonolysis reactions as well. Appropriate chemical characterization of the lignin content in bagasse before and after its ozonation was also carried out. © 2013 American Chemical Society.1171131103119Zakzeski, J., Bruijnincx, P.C.A., Jongerius, A.L., Weckhuysen, B.M., The Catalytic Valorization of Lignin for the Production of Renewable Chemicals (2010) Chem. Rev., 110, pp. 3552-3599Sun, Y., Cheng, J., Hydrolysis of Lignocellulosic Materials for Ethanol Production: A Review (2002) Bioresour. Technol., 83, pp. 1-11Mosier, N., Wyman, C., Dale, B., Elander, R., Lee, Y.Y., Holtzapple, M., Ladisch, M., Features of Promising Technologies for Pretreatment of Lignocellulosic Biomass (2005) Bioresour. Technol., 96, pp. 673-686Kumar, P., Barrett, D.M., Delwiche, M.J., Stroeve, P., Methods for Pretreatment of Lignocellulosic Biomass for Efficient Hydrolysis and Biofuel Production (2009) Ind. Eng. Chem. Res., 48, pp. 3713-3729Crestini, C., D'Auria, M., Photodegradation of Lignin: The Role of Singlet Oxygen (1996) J. Photochem. Photobiol., A, 101, pp. 69-73Crestini, C., D'Auria, M., Singlet Oxygen in the Photodegradation of Lignin Models (1997) Tetrahedron, 53, pp. 7877-7888Bonini, C., Auria, M.D., Alessio, L.D.'., Mauriello, G., Tofani, D., Viggiana, D., Zimbardi, F., Singlet Oxygen Degradation of Lignin (1998) J. Photochem. Photobiol., A, 113, pp. 119-124Sarkanen, K.V., Islam, A., Anderson, C.D., (1992) Methods in Lignin Chemistry, pp. 387-406. , Lin, S. Y. Dance, C. W. Springer-Verlag: BerlinBinder, A., Pelloni, L., Fiechter, A., Delignification of Straw with Ozone to Enhance Biodegradability (1980) Eur. J. Appl. Microbiol. Biotechnol., 11, pp. 1-5Mbachu, R.A.D., Manley, R., St, J., Degradation of Lignin by Ozone I: The Kinetics of Lignin Degradation of Ozone (1981) J. Polym. Sci., Polym. Chem., 19, pp. 2053-2063Vidal, P.F., Molinier, J., Ozonolysis of Lignin: Improvement of in vitro Digestibility of Poplar Sawdust (1988) Biomass, 16, pp. 1-17Kwon, J.-Y., Chung, P.-G., Lim, I.-H., Removal of Residual COD in Biologically Treated Paper-Mill Effluent and Degradation of Lignin Using Nonthermal Plasma Unit (2004) J. Environ. Sci. Health, Part A, 39, pp. 1853-1865Schultz-Jensen, N., Leipold, F., Bindslev, H., Thomsen, A.B., Plasma-Assisted Pretreatment of Wheat Straw (2011) Appl. Biochem. Biotechnol., 163, pp. 558-572Schultz-Jensen, N., Kádár, Z., Thomsen, A.B., Bindslev, H., Leipold, F., Plasma-Assisted Pretreatment of Wheat Straw for Ethanol Production (2011) Appl. Biochem. Biotechnol., 165, pp. 1010-1023Bailey, P.S., (1978) Ozonation in Organic Chemistry: Olefinic Compounds, 1. , Academic Press: New YorkEriksson, T., Gierer, J., Studies on the Ozonation of Structural Elements in Residual Kraft Lignins (1985) J. Wood Chem. Technol., 5, pp. 53-84Heitner, C., Dimmel, D., Schmidt, J.A., (2010) Lignin and Lignans: Advances in Chemistry, , Taylor & Francis Group: Boca Raton, FLCriegee, R., Mechanism of Ozonolysis (1975) Angew. Chem., Int. Ed., 14, pp. 745-751Nascimento, E.A., Morais, S.A.L., Aquino, F.J.T., Piló-Veloso, D., Ozonólise das Ligninas Organossolve e Kraft Eucalipto. Parte II: Cinética nos Meios ácido e Básico (1998) Quím. Nova, 21, pp. 578-583Bentley, K.W., (1963) Techniques of Organic Chemistry Part 2, 11, pp. 875-906. , Weissberger, A. Wiley-Interscience: New YorkBailey, P., (1975) Ozone Chemistry and Technology, pp. 77-83. , Murphy, J. S. Orr, J. R. The Franklin Institute Press: Philadelphia, PARagnar, M., (2000) On the Importance of Radical Formation in Ozone Bleaching, , Ph.D. Thesis, Royal Institute of Technology, Department of Pulp and Paper Technology, Department of Wood Chemistry, Stockholm, SwedenSaito, K., Kato, T., Tsuji, Y., Fukushima, K., Identifying the Characteristic Secondary Ions of Lignin Polymer Using ToF-SIMS (2005) Biomacromolecules, 6, pp. 678-683Saito, K., Kato, T., Takamori, H., Kishimoto, T., Yamamoto, A., Fukushima, K., A New Analysis of the Depolymerized Fragments of Lignin Polymer in the Plant Cell Walls Using ToF-SIMS (2006) Appl. Surf. Sci., 252, pp. 6734-6737Saito, K., Kishimoto, T., Matsushita, Y., Imaia, T., Fukushima, K., Application of TOF-SIMS to the Direct Determination of Syringyl to Guaiacyl (S/G) Ratio of Lignin (2011) Surf. 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Activity measurements of 192Ir solid sources using a well-type ionization chamber

This work presents the preliminary activity measurements of 192Ir solid sources, applied in industrial gammagraphy, produced by the Sealed Sources Laboratory in the Radiation Technology Center (CTR) at IPEN-CNEN/SP. The pellets' activity measurements were carried out with a well-type ionization chamber developed at CTR. The chamber current-voltage response was studied as a function of 192Ir activities ranging from 27 GBq (0.75 Ci) to 4.1 TBq (110 Ci), under constant geometrical conditions. The results obtained have shown both the linearity of the ionization current and the absence of appreciable recombination or diffusion losses.http://www.sciencedirect.com/science/article/B6TJM-4NRK4D4-M/1/30974d373abe73fe6692499b4a633cb

Electron impact ionization and fragmentation of biofuels

We present in this article, a review of our recent experimental and theoretical studies published in the literature on electron impact ionization and fragmentation of the primary alcohols methanol, ethanol, 1-propanol and 1-butanol (C1–C4). We discuss the mass spectra (MS) of these alcohols, measured for the electron impact energy of 70 eV and also, total (TICS) and partial (PICS) ionization cross sections in the energy range from 10 to 100 eV, which revealed the probability of forming different cations, by either direct or dissociative ionization. These experimental TICS are summarized together with theoretical values, calculated using the Binary-encounter Bethe (BEB) and the independent atom model with the screening corrected additivity rule (IAM-SCAR) methods. Additionally, we compared data of appearance energies – AE and discussed the application of the extended Wannier theory to PICS in order to produce the ionization and ionic fragmentation thresholds for the electron impact of these alcohols