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231.
R. Meyer zu Reckendorf 《Chromatographia》1997,45(1):173-182
Summary The ring furnace baking process is an intermediate step in the production of graphite electrodes. In this process coal tar
pitch is pyrolized to form amorphous carbon and volatile aromatic and polycyclic aromatic compounds (PACs). These gaseous
ring furnace emissions were analysed by GC-MS and GC-AED. As a result of the pyrolytic reactions taking place, several phenyl-substituted
PACs are generated, which were identified by their chromatographic retention indices and mass spectra. Pure reference compounds
were analysed for verification if available. A number of phenyl-PACs are reported to be present in coal tar-related material,
including phenylpyridines and phenyldibenzofurans previously unreported. A formation scheme for phenyl-dibenzofurans on the
basis of a radical mechanism is proposed.
Dedicated to Prof. Dr. Wolfgang Meyer zu Reckendorf, Münster, on the occasion of his 65th birthday.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
232.
We present a method for the decomposition of the mass spectra of mixed gases using Bayesian probability theory. The method works without any calibration measurement and therefore applies also to the analysis of spectra containing unstable species. For the example of mixtures of three different hydrocarbon gases the algorithm provides concentrations and cracking coefficients of each mixture component and also their confidence intervals. The amount of information needed to obtain reliable results and its relation to the accuracy of our analysis are discussed. 相似文献
233.
P. S. Bhandare B. K. Lee K. Krishnan 《Journal of Thermal Analysis and Calorimetry》1997,49(1):361-366
Thermogravimetric analysis (TG) provides information regarding mass changes in the sample resulting from heat treatment under controlled environment. However, it does not provide any chemical information regarding the gases evolved during the thermal degradation. Using FT-IR spectrometry in combination with TG, it is often possible to identify the evolved gases, and also monitor their evolution profiles during thermal degradation. In this study, we present the TG/FT-IR combined analysis of incineration and pyrolysis of some common plastics such as high density polyethylene (HDPE), polyvinyl chloride (PVC), polyethylene terephthalate (PET), and polystyrene (PS). This study demonstrates the utility of such combined analysis in providing useful information regarding the use of thermal treatment for recycling or incineration. 相似文献
234.
S. J. Hawkes 《Chromatographia》1993,37(7-8):399-401
Summary Equations are derived for viscosities of H2, He, N2 and Ar for use at chromatographic temperatures which are accurate to within 0.3% for H2, and 0.1% for the other gases. The effect of pressure is usually negligible but may increase the viscosity of N2 or Ar by as much as 0.5% at 25°C or lower and 5 atm or higher. 相似文献
235.
Summary The gases evolved from geothermal fields, after condensation of H2O, CO2, H2S and NH3 in caustic solution, contain He, H2, Ar, O2, N2, CH4 and higher hydrocarbons. The analysis for the major components in these residual gas mixtures can be achieved by use of two simple gas chromatographs in parallel, and using 5Å molecular sieve. The separation of He and H2 to baseline is achieved by using low temperatures (30°C) coupled with a relatively long column; and the difficult separation of Ar and O2 is achieved by use of a cryogenically cooled column. The use of switching valves to backflush and bypass columns ensures that a minimum time for analysis can be achieved whilst retaining baseline separations of the He/H2 and Ar/O2 pairs. 相似文献
236.
237.
V. S. Sevast’yanov E. M. Galimov N. E. Babulevich A. A. Arzhannikov 《Russian Journal of Electrochemistry》2007,43(4):448-453
It is demonstrated that a high-temperature electrochemical reactor on the basis of zirconium dioxide (0.9ZrO2 · 0.1Y2O3) with platinum electrodes may be promising as a device for preparing samples of organic gases for isotopic assay of carbon.
Owing to a high catalytic activity of the surface of a porous platinum coating, it is possible to realize full oxidation of
organic gases to stoichiometric oxides at 900–950°C and an oxygen flux equivalent to an electric current of 100 μA and higher.
The reproducibility of the results of isotopic assay is better than that yielded by a standard oxidation reactor. Use of the
solid-electrolyte reactor in a new device as a sensor makes it possible to simultaneously measure the concentration of organic
gases passing through the reactor on the basis of the charge transported by oxygen ions through the wall of a ceramic tube.
Simultaneously one can monitor purity of the carrier gas.
Original Russian Text ? V.S. Sevast’yanov, E.M. Galimov, N.E. Babulevich, A.A. Arzhannikov, 2007, published in Elektrokhimiya,
2007, Vol. 43, No. 4, pp. 472–478. 相似文献
238.
Striegel AM 《Journal of chromatography. A》2002,960(1-2):151-158
The application of film-forming organic polymers, which are in common use in membrane technology, as chromatographic adsorbents for packed and capillary columns has been suggested. The chromatographic characteristics of poly[1-(trimethylsilyl)-1-propine] (PTMSP) as an adsorbent were studied. The film-forming properties of PTMSP simplify manufacturing of capillary and packed gas–solid columns. It was shown that separation of C1–C4 hydrocarbon gases on the columns with PTMSP is of practical interest. In the authors’ opinion, PTMSP is also promising for the separation of inorganic gases. 相似文献
239.
The present work is concerned with checking a new and simple pair potential function (soft‐core double Yukawa potential) for noble gases by calculation of the transport properties. The viscosity, thermal conductivity and self diffusion coefficient in dilute gas limit in the temperature range of 298‐1400 K are calculated and agreement with the measurements is, in general, within the experimental error. A comparison of the calculated and experimental values of the viscosity, thermal conductivity and the diffusion coefficients yields an average absolute deviation of 0.5%, 1.5% and 1.2%, respectively. Also, the calculated transport properties from this potential have been compared with those calculations via the accurate experimental potential and also the corresponding state. 相似文献
240.
Viktor G. Berezkin Irina V. Malyukova Victor R. Alishoev Jaap de Zeeuw 《Journal of separation science》1996,19(5):272-276
In capillary gas-solid chromatography where interactions between solute and carrier gas and adsorption of the solute on the surface of the adsorbent are considered to be imperfect, it has been shown that chromatographic retention is determined largely by adsorption processes. It has been established that correlation relationships k(P2)=A k(P1) + B, where k is the retention factor, and A and B are equation constants, was valid for use of different carrier gases P1 and P2. Column efficiency could be improved by use of carbon dioxide. The advantages of using carbon dioxide as the carrier gas were investigated. 相似文献