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Determination of carbon monoxide,methane and carbon dioxide in refinery hydrogen gases and air by gas chromatography 总被引:2,自引:0,他引:2
Kamiński M Kartanowicz R Jastrzebski D Kamiński MM 《Journal of chromatography. A》2003,989(2):277-283
This paper illustrates a method for determining trace amounts of CO, CH4 and CO2 with the detection limit of 0.15, 0.15 and 0.20 microg/l, respectively, in refinery hydrogen gases or in air. A simple modification of a gas chromatograph equipped with a flame-ionization detector is presented. A Porapak Q column, additionally connected with a short molecular sieve 5A packed column and a catalytic hydrogenation reactor on the Ni catalyst have been applied. The principle of the analytical method proposed is the separation of CO from O2 before the introduction of CO to the methanizer. The analytical procedure and examples of the results obtained have been presented. The modification applied makes it possible to use the GC instrument for other determinations, requiring utilization of the Porapak Q column and the flame-ionization detector. In such cases, the short molecular sieve 5A column and the methanizer can be by-passed. 相似文献
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Magnucki Krzysztof Lewinski Jerzy Cichy Rafal 《Archive of Applied Mechanics (Ingenieur Archiv)》2019,89(10):2103-2114
Archive of Applied Mechanics - The paper is devoted to simply supported beams subjected to non-uniformly distributed loads. Shapes of bisymmetrical cross sections of the beams are expressed by... 相似文献
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Andrzej W. Domanski Rafal Cieslak Miroslaw A. Karpierz Daniel Budaszewski Tomasz R. Wolinski 《Central European Journal of Physics》2008,6(3):628-633
This paper analyzes the second harmonic generation (SHG) efficiency of light with partial temporal coherence due to depolarization
effects in birefringent media. It discusses relations between SHG efficiency fading, light source spectrum, crystal birefringence,
and phase matching conditions. The efficiency of SHG pumped by the partially coherent light beam that may depolarize light
in nonlinear birefringent crystal is also analyzed. The basic theory of SHG with its modification for partially coherent light
with depolarization and some numerical calculations of the SHG process are described.
Presented at 9-th International Workshop on Nonlinear Optics Applications, NOA 207, May 17–20, 2007, Świnoujście, Poland 相似文献
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We have used SOM and grid 3D and 4D QSAR schemes for modeling the activity of a series of dihydrofolate reductase inhibitors. Careful analysis of the performance and external predictivities proves that this method can provide an efficient inhibition model. 相似文献
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Donor activity of cyclohexene and a series of n-alkanes in catalytic hydrogen transfer to various organic groups over magnesia as a catalyst has been determined. Styrene, phenylacetylene, benzaldehyde and acetophenone were not reduced by cyclohexene in the temperature range 523-673 K. Cyclohexene oxide was reduced to cyclohexanol (38%) and nitrobenzene to aniline (56%) by cyclohexene under adopted conditions (673 K). The highest yield of aniline (57%) from nitrobenzene was reached at 673 K in the presence of n-decane from a series of C6 - C16 n-alkanes used as hydrogen 相似文献
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Rafal Kamocki 《Mathematical Methods in the Applied Sciences》2014,37(11):1668-1686
In the paper, fractional systems with Riemann–Liouville derivatives are studied. A theorem on the existence and uniqueness of a solution of a fractional ordinary Cauchy problem is given. Next, the Pontryagin maximum principle for nonlinear fractional control systems with a nonlinear integral performance index is proved. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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