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Abstract  

Quartz crystal microbalances have high mass sensitivities. Their application in gas sensing has been limited because they are required to have both high selectivity and reversibility. Yet by the inherent nature of their operation these properties are mutually exclusive. One approach to this problem is to use an array of quartz crystal microbalances. We have used an array of six coated quartz crystal microbalances for the classification of methanol, propan-1-ol, butan-1-ol, hexane, heptane and toluene. A novel classification scheme using fuzzy membership functions was found to be highly efficient.

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Orvosi Hetilap
Authors: István Pregun and Zsolt Tulassay

Suarez, F. L., Levitt, M. D.: Intestinal gas. In: Feldman, M., Friedman, L. S., Sleisenger, M. H. Gastrointestinal and liver diseases. Philadelphia: Saunders, 2002, 155

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References [1] Standard STN EN 1279-3 ( 2004 ), Glass in building. Insulating glass units . Part 3: Long term test method and requirements for gas leakage rate and

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Pollack Periodica
Authors: Olena Savchenko, Vasyl Zhelykh, Yuriy Yurkevych, Stepan Shapoval, and Khrystyna Kozak

] Order of the Ministry of Fuel and Energy of Ukraine , No. 264 dated May 30, 2003, On approving methods for determining specific losses and production and technological costs of natural gas during its transportation by gas distribution

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] C. Myren et al . Catalytic tar decomposition of biomass pyrolysis gas with a combination of dolomite and silica . Biomass and Bioenergy 23 ( 2002 ) 217 – 227 . [77

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1 Introduction Natural gas hydrates are crystalline solids composed of water and gas. The gas molecules are trapped in water cavities that are composed of hydrogen-bonded water molecules [ 1 ]. Typical natural gas composition includes methane

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application of pulsed corona processing to flue gas, NATO ASI Series , Vol. G, Part B, Springer-Verlag, Berlin, 1993. Civitano L. NATO ASI Series, Vol. G

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Abstract  

A wide variety of liquid streams are generated as part of the process research and development effort. Frequently these streams are drummed off, either as intermediates that must be held for processing or as wastes that must be sent off-site for disposal. Because of the long times and low concentrations often involved, current thermoanalytical techniques were inadequate to detect the potential of streams to generate gas. A custom-made apparatus, the gas evolution test cell (GETC), was developed in the Merck Research Laboratories to measure the gas generation potential of various streams under precisely defined conditions, is the key innovation for the development of a quantitative gas-generation test method.

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Nanocrystalline TiO2/SnO2 composites for gas sensors

An International Forum for Thermal Studies

Journal of Thermal Analysis and Calorimetry
Authors: M. Radecka, A. Kusior, A. Lacz, A. Trenczek-Zajac, B. Lyson-Sypien, and K. Zakrzewska

Introduction Metal oxides, such as TiO 2 , SnO 2 , ZnO, WO 3 , and Fe 2 O 3 , are well known for their remarkable ability to change the electrical resistivity in response to oxidizing and reducing gases. Gas sensing properties

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Abstract  

A pressurized ionization chamber detector able to measure radioactive sources in internal 2π or 4π geometry was built in order to characterize alpha and beta radioactive sources, i.e. to calibrate these sources by a relative method, and to test the behavior of gas mixtures in pressurized-gas radiation detectors. The detector we made is of spherical shape and works by collecting in a quasi-uniform electric field the ionization charges resulting from the interaction of ionizing radiation with gas in the sensitive volume of the chamber. An ionizing current proportional to the activity of the radioactive source to be measured is obtained. Pressure inside the detector in standard conditions is maximum 6 × 105 Pa at 22 °C and the maximum allowed voltage is 3000 V. It is presented as a spherical ionization chamber with gas under pressure, geometrical shape, dimensions and structural characteristics, functional and technical parameters and preliminary experimental results obtained from radiation measurements in the laboratory SALMROM of the IFIN-HH.

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