16 Fuel science and technology (fundamental science, analysis, instrumentation)

95lO3170 Quantitative analysis ot N-methyl-2-pyrrolldlnone retalned In coal extracts by thermal extractlon g-c.-m.8. Chervenick, S. W. and Smart, R. B. Fuel, Feb. 1995, 74, (2), 241-245. N-methyl-2-pyrrolidinone (NMP) is widely used for coal extractions. It is well known that extraction solvents are retained in the coal extracts even after extensive drying procedures. The amount of NMP retained will affect the accuracy of the extraction yield and the character of the extracts. Ther- mal extraction gas chromatograph -mass spectrometry (g.c.-m.s.) has been applied to quantify the amount o r NMP retained in coal extracts. Several NMP related compounds are found in the coal extracts, but not in the whole coals. NMP was added to activated carbon and this material used as a standard to produce a linear calibration curve.

95lO3171 Relatlonshlp between reflectance and structure of hlgh surface area carbons Jagtoyen, M. et al., Fuel, Apr. 1995, 74, (4). 610-614. Reflectance measurements have been used to try to track the structural alterations during activated carbon synthesis by chemical activation. H,PO, has been used as a chemical reagent with white oak, subbituminous coal and a bituminous coal, and KOH with a bituminous coal. The reflectance of thermally treated carbons follows a single correlation with heat treat- ment temperature (H’IT), consistent with thermally induced increases in aromaticity and structural order. For chemically activated carbons, the rela- tionship between reflectance and H’IT depends upon the precursor-activant combination that is used.

95/03172 Sampllng and analysls ot trace emlsslons from coal-tlred power statlons Sloss, L. and Gardner, C. I.U Coal Research, Publications Dept., Gemini House, IO-18 Putney Hill, London SW15 6AA, IEACRl77, f450.00, Feb. 1995. The report investigates the problems involved in the sampling and analysis of trace emissions from coal. Increasing awareness of the environment and the detrimental effects of many pollutants in the atmosphere has led to a greater demand for the accurate measurement of trace emissions.

95103173 Scope and llmltatlon ot ruthenlum Ion catalyzed oxldatlon of coal as an analytlcal tool for an allphetlc portlon ot coal organic materials Murata, S. et al., Prepr. Pap.-Am. Chem. Sot., Div. Fuel Chem., 1994,39, (3), 787-790. Describes the quantitative determination of carboxylic acids resulting from the RuCl,-NaIO, oxidation of coals.

95103174 Semlquantltatlve gas chromatographlc analysis of the volatlle tractlon In several extracts obtalned by treatment of coal tar oltches wlth dlfferent oraanlc solvents Guillen, &I. D. et al., Fuel, Feb. 195, 74, (2), 233-240. The solubility of four coal tar pitches in several organic solvents and the semiquantitative gas chromatographic analysis of the corresponding vola- tile fraction extracts are discussed. Close relationships between the extrac- tion yield and the chromatographic material concentration of the several extracts studied are found. These correlations show that the increase in extraction ability from one solvent to another is basically due to the sol- vent’s ability to extract unchromatographed compounds of high molecular weight. In general, hexane (pentane) and methanol extract chromato- graphic fractions have a smaller concentration of compounds of high molecular weight. No solvent selectivity towards olycyclic aromatic hydrocarbon, oxygenated compounds and thiophene erivatives is found. B

95/03175 coal

Simple method for automated quallty control of

Gorlov, Y. I. and Onishchenko, A. M. Koks Khim., 1994, (8), 25-27. (In Russian) Modifications are proposed for systems for simultaneous online ash and sulphur determination in coal by reflection gamma-spectrometry.

95103 176 Simple method for smoothln ?l

multldlmenslonal experlmental data wlth appllcatlon to the C F and postdryout look-up tables Huang, X. C. and Cheng, S. C. Numerical Heat Transfer, Part B, Dec. 1994, 26, (4), 425-438. A simple mathematical model has been developed that is suitable for smoothing multidimensional tabulated data subject to random errors. This method &superior for multidimensional problems compared with the least- square spline, which, when extended to multidimensinal cases, encounters substantial difficulty in conjuction with the choice of appropriate node points. The applicability of the present method has been demonstrated in the smoothing of a three-dimensional critical heat flux look-up table and a four-dimensional postdryout look-up table.

95103177 Slmulatlon ot shock-wave retlectlon In a one- dlmenslonal shock tube uslng smoothed hydrodynamlcs

particle

McCormick, C. S. and Miller, T. F. Numerical Heat Transfer, Part B, Dec. 1994, 26, (4), 473-488.

95103178 Speclal report: Meterlng The Australian Gas, Feb. 1995, 59, (l), 25-26.

Gas flow measurement aims to know the quantity of gas which passes through a piping section during a specified period. This quantity will be ultimately expressed in mass or energy units for billing purposes. The primary physical parameter to be measured is gross volume, with the help of manual or automatic correction. Discusses the history of gas meters since 1815 when Samuel Clegg made the first practical gas meter in England

;~op3:;9 A step forward wlth the tlrst Glveg approval mark

Stam, B. Gas (Netherlands), Feb. 1995, 115, (2), p. 43. (In Flemish) PLCs, Programmable Logic Controls, are electronic controls suitable for various applications. Theu operation is defined by means of a user pro- gram. In the gas industry, PLCs, have been used for some time now for controlling industrial processes. Recently, the first Giveg approval mark was granted for a PLC system: the FSC system of Safety Management Systems. This means that a giant step forward has been made in the Dutch gas industry. For PLC manufacturers, the users of the installation as well as inspection companies (energy utilities and/or Gasunie) it has become clear for which safety-critical functions within the gas industry PLCs can be used.

95/03190 Study of double-dlffuslve convectlon In layered anlsotroplc porous medla Nguyen, H. D. et al., Numerical Heat Transfer, Part B, Dec. 1994, 26, (4j, 489-505. Natural convection induced by combined heat and mass transfer in an enclosure filled with two layers of anisotropic porous media saturated with a two-component fluid is investigated by means of numerical experiments. Darcy’s law together with the energy and specie equations are solved by a domain decomposition and a pseudo-spectral method using Chebyshev polynomials as the basis functions.

95/03191 Theorv ot a tloatlna random-walk alaorlthm for solvlng the steady:stete heat eqiatlon In complex; materially Inhomogeneous rectlllnear domalns Le Coz, Y. L. et al., Numerical Heat Transfer, Part B, Oct.-Nov. 1994, 26, (3), 353-366. Presents theory and preliminary numerical results for a new random-walk algorithm that solves the steady-state heat equation subject to Dirichlet boundary conditions.

95lO3182 Thermally drlven convectlon In enclosed com- oresslble flulds krocker, D. S. and Parang, M. 1994, 26, (5), 569-585.

Numerical Heat Transfer, Part A, Nov.

The pa ity an B

er presents a numerical scheme for the solution of unsteady veloc- temperature fields in an enclosed compressible fluid that is sub-

jetted to thermally induced mechanical motion.

95iQ3103 lnstablllty

Thermocaplllary-drlven flow past the Marangonl

Evren-Selamet, E. et al., Numerical Heat Transfer, Part A, Nov. 1994, 26. 15‘). 521-535. , \ ,, A top free liquid layer is heated from the bottom in a two-dimensional rectangular container with insulated side walls. The resulting thennocapil- lary motion is predicted by the projection method involving a Godunov- type discretization for convective terms. The velocity and temperature fields beyond those predictable via infinitesimal theories are discussed in terms of ihe Marangoni number, Prandtl number, Biot number, and aspect ratio.

95103104 Translent conductlon under cosine temperature perturbatlons Antonopoulos, K. A. and Democritou, F. 233-246.

Applied Energy, 1995, 50, (3),

An analytical solution is presented for the transient, non-periodic, one- dimensional, non-homogeneous boundary-value problem of wall heat con- duction, taking into account temporary deviations of the outdoor air tem- perature from its repeated daily cycle. The usual assumption of periodic outdoor conditions is not made here, thus avoiding considerable errors in the case of unforeseen perturbations in outdoor conditions.

95103185 The ultrasonlc gas volume meter Rouwhorst, H. and Ter Horst, G. Gas (Netherlands), Dec. 1994, 114, (12), 642-643. (In Flemish) If mass production and electronics developments force down the price of the ultrasonic gas meter, it may gain a substantial market share from con- ventional measuring methods. To manufacturers it is hardly interesting at the moment, however, to develop accountable gas meters for the intema- tional market. This is due to each country having its own calibration regu- lations. A uniform European calibration scheme could open up the market and stimulate manufacturers. Not before that time will the introduction of the ultrasonic flow meter into the public gas supply sector be a fact.

Fuel and Energy Abstracts May 1995 225