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91.
L. H. Johnston S. R. Raju G. R. Sudhakaran R. M. Lees 《International Journal of Infrared and Millimeter Waves》1982,3(4):517-527
Laser-Stark spectra have been observed for methyl alcohol using the 311 m line of the HCN laser. Partial assignments are presented for the three most distinctive structures in the spectra. The low field structure is clearly associated with a member of the J=2019qRa-type multiplet, and is tentatively identified as the k=13 A vt=0 transition. The other two structures originate from the 9382 E vt=0 transition, and from a member of the k= 65 A vt=1 Q branch, tentatively assigned as the J=32 member. 相似文献
92.
H. A. Al-Salah H. X. Xiao J. A. McLean Jr. K. C. Frisch 《Journal of polymer science. Part A, Polymer chemistry》1988,26(6):1609-1620
Polyurethane (PU) cationomers have been synthesized by quaternizing tertiary amine-containing linear polyurethanes using different quaternizers containing acid groups. The effect of chemical structure of PU cationomers on the physical properties was studied. The mechanical properties of PU cationomers were improved with decreasing molecular weight of poly(caprolactone) glycol, and increasing concentration of quaternary ammonium. Decreasing the carbon number in the alkyl group of the N-alkyl diethanol-amine chain-extenders, and using rigid symmetrical diisocyanates, the mechanical properties of the PU cationomers were increased. The effects of these factors on the glass transition temperature of PU cationomers were also examined. The mechanical properties of the PU cationomers decreased by immersion in water and recovered after removal of the water. 相似文献
93.
It is argued that preparation of a quantum state characterized by density operator not commuting with a superselection operatorQ does not by itself constitute an instance of superselection rule violation. It would, however, be an instance of state restriction violation. It is held that superselection rule violation is only possible with simultaneous observable and state restriction violations. It is shown that it is a priori conceivable to subdivide an ensemble whose satisfies[, Q] = 0 into subensembles whose density operators violate the state restrictions. The dynamics of the subdivision process is not considered. 相似文献
94.
S. Kohn J. A. Brown R. H. Heffner C. Y. Huang T. A. Kitchens Jr. M. Leon C. E. Olsen M. E. Schillaci W. B. Gauster 《Hyperfine Interactions》1979,6(1-4):283-287
The + depolarization rate in diluteAlGd alloys containing 50 and 450 atomic ppm Gd was measured in a transverse field of 80 Oe over the temperature range 6–300 K. For both alloys, A increased dramatically above 200 K, reaching values of 0.69 and 0.93 s–1, respectively, near room temperature. The results are interpreted as providing evidence for a thermally-activated trapping mechanism.This work was supported by the U.S. Department of Energy. 相似文献
95.
Robert M. Burton Jr. 《Probability Theory and Related Fields》1979,47(2):205-212
Summary Let GZn be a group of measure preserving transformations of a Lebesgue space. J. P. Conze [1] has developed an entropy theory for such groups and described a class of groups obeying a form of the Kolmogorov zero-one law called K-groups. A Bernoulli group is a group isomorphic to the group of translates (shifts) of elements of the space
with product measure where X
g
=X is a probability space. Bernoulli groups are also K-groups. Katznelson and Weiss [3] have shown entropy is a complete invariant for isomorphism classes of Bernoulli groups. We give an asymptotic definition of K-groups in terms of finite -algebras and justify this definition in terms of entropy and Conze's formulation. This definition s used to help us construct a K-group GZ
n
that is completely non-Bernoulli, that is one that contains no Bernoulli subgroup. 相似文献
96.
Marcia Araque-Marin Fabio Bellot Noronha Mickel Capron Franck Dumeignil Michle Friend Egon Heuson Ivaldo Itabaiana Jr. Louise Jalowiecki-Duhamel Benjamin Katryniok Axel Lfberg Sbastien Paul Robert Wojcieszak 《Molecules (Basel, Switzerland)》2022,27(12)
The development of the future French and European bioeconomies will involve developing new green chemical processes in which catalytic transformations are key. The VAALBIO team (valorization of alkanes and biomass) of the UCCS laboratory (Unité de Catalyse et Chimie du Solide) are working on various catalytic processes, either developing new catalysts and/or designing the whole catalytic processes. Our research is focused on both the fundamental and applied aspects of the processes. Through this review paper, we demonstrate the main topics developed by our team focusing mostly on oxygen- and hydrogen-related processes as well as on green hydrogen production and hybrid catalysis. The social impacts of the bioeconomy are also discussed applying the concept of the institutional compass. 相似文献
97.
Renzo C. Silva Giovanna F. Carneiro Lúcio L. Barbosa Valdemar Lacerda Jr. Jair C. C. Freitas Eustáquio V. R. de Castro 《Magnetic resonance in chemistry : MRC》2012,50(2):85-88
Low‐field 1H NMR was used in this work for the analysis of mixtures involving crude oils and water. CPMG experiments were performed to determine the transverse relaxation time (T2) distribution curves, which were computed by the inverse Laplace transform of the echo decay data. The instrument's ability of quantifying water and petroleum in biphasic mixtures following different methodologies was tested. For mixtures between deionized water and petroleum, one achieved excellent results, with root mean squared error of cross‐validation (RMSECV) of 0.8% for a regression between the water content (wt %) and the relative area of the water peak in the T2 distribution curve, or a standard deviation of 0.9% for the relationship between the water content and the relative water peak area, corrected by the relative hydrogen index of the crude. In the case of biphasic mixtures of Mn2+‐doped water and crude oils, the best result of RMSECV = 1.6% was achieved by using the raw magnetization decay data for a partial least squares regression. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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