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991.
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The pre-use state of industrial α-Fe2O3/Cr2O3 CO-conversion catalysts of known activity has been investigated by means of MÖSSBAUER effect and BET measurements. The iron of various catalyst samples has been found at room and catalytic reaction temperature (330°C) to be as well in the antiferro- as in the paramagnetic state, the ratio of both states being strongly dependent on temperature and on the specific catalyst sample. As the main reason for the occurrence of these two states within each sample the simultaneous occurrence of differently sized powder particles may be supposed. The ratio difference between one and another sample is due to differing chemical composition and grain size. Since no correlation was found between these resulats, BET surface data, grain size distribution and/or catalytic activity, pore structure differences are assumend to explain the observed differences in sample activity. 相似文献
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995.
Alfred Lehman 《Mathematical Programming》1979,16(1):245-259
This paper was written at the Rensselaer Polytechnic Institute in 1963. A lecture based on it was given at the Rand Corporation in 1965 and this version is in the form in which Ray Fulkerson received it at Rand.The paper is the underpinning for results on resistor network inequalities (Reference [4]) which has not been published. A specific example, however, appears inProceedings of the IEEE 51 (1963) 1047–1048.More is known about minimal non-W—L matrices. U. Peled has found several additional classes of matrices which are also classically known in other contexts. A consequence of a recent matrix theorem is apparently that the degenerate projection planes are the only minimal matrices requiring unequal weights.The preparation of this paper was supported by the National Science Foundation under grant GP-14.
Editor's Note: This paper, although written in 1963, was sought for inclusion inMathematical Programming Study 8—Polyhedral Combinatorics, which was dedicated to the memory of D.R. Fulkerson. Unfortunately, an editorial mishap prevented its inclusion. Nevertheless, the historical importance of the paper, the fact that it has been widely referenced and influenced Fulkerson's and others' work in the area has convinced the Editor that it should be published and hence made readily available. Alfred Lehman has given his assent to this despite his reluctance to publish a paper which is not current. 相似文献
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997.
Alfred Zeman 《Fresenius' Journal of Analytical Chemistry》1982,310(3-4):243-249
Zusammenfassung Zur Produktkontrolle und QualitÄtsbeurteilung von Esterölen werden leistungsfÄhige Analysenverfahren benötigt. Dies gilt besonders für die Beurteilung von gebrauchten ölen. Es wird am Beispiel der Neopentylpolyolesteröle gezeigt, da\ die Capillar-Gas-Chromatographie in Kombination mit der CI(NH3)-Massenspektrometrie einen erheblichen Fortschritt bei der Charakterisierung von komplexen Esterölen und ihren Additivsystemen darstellt.
Analysis of synthetic lubricating oils based on esters by gas chromatography-CI(NH3)-mass spectrometry
Summary For product control and quality assessment of ester oils efficient analytical methods are needed. This is especially true for the assessment of used oils. It is shown with neopentylpolyol ester oils that capillary gas chromatography in combination with chemical ionization (NH3)-mass spectrometry presents a considerable progress in the characterisation of complex ester oils and their additive systems.相似文献
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Alfred Huber 《Commentarii Mathematici Helvetici》1972,47(1):409-420
Ohne Zusammenfassung
Zum Teil verfasst w?hrend eines von der National Science Foundation unterstützten Aufenthaltes an der University of Washington
in Seattle. 相似文献