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111.
Enantioselective total synthesis of anti HIV-1 active (+)-calanolide A was achieved by a quinine-catalyzed asymmetric intramolecular oxo-Michael addition as a key step. 相似文献
112.
Ichiro Nishizaki Hideki Katagiri Tomohiro Hayashida 《Central European Journal of Operations Research》2010,18(3):383-396
A multiattribute utility function can be represented by a function of single-attribute utility functions if the decision maker’s
preference satisfies additive independence or mutually utility independence. Additive independence is a preference condition
stronger than mutually utility independence, and the multiattribute utility function is in the additive form if the former
condition is satisfied, otherwise it is in the multiplicative form. In this paper, we propose a method for sensitivity analysis
of multiattribute utility functions in multiplicative form, taking into account the imprecision of the decision maker’s judgment
in the procedures for determining scaling constants (attribute weights). 相似文献
113.
Tomohiro Hirano Kousuke Higashi Makiko Seno Tsuneyuki Sato 《Journal of polymer science. Part A, Polymer chemistry》2004,42(19):4895-4905
We have reported that intramolecular chain‐transfer reaction takes place in radical polymerization of itaconates at high temperatures and/or at low monomer concentrations. In this article, radical polymerizations of di‐n‐butyl itaconate (DBI) were carried out in toluene at 60 °C in the presence of amide compounds. The 13C‐NMR spectra of the obtained poly(DBI)s indicated that the intramolecular chain‐transfer reaction was suppressed as compared with in the absence of amide compounds. The NMR analysis of DBI and N‐ethylacetamide demonstrated both 1:1 complex and 1:2 complex were formed at 60 °C through a hydrogen‐bonding interaction. The ESR analysis of radical polymerization of diisopropyl itaconate (DiPI) was conducted in addition to the NMR analysis of the obtained poly(DiPI). It was suggested that the suppression of the intramolecular chain‐transfer reaction with the hydrogen‐bonding interaction was achieved by controlling the conformation of the side chain at the penultimate monomeric unit of the propagating radical with an isotactic stereosequence. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4895–4905, 2004 相似文献
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117.
Tomohiro Okuma 《Compositio Mathematica》1998,110(3):263-276
This paper studies the second pluri-genus of surface singularities. We give a formula for this invariant of a Gorenstein singularity, and several inequalities relating the invariant with the Milnor number, Tjurina number and the modality of a hypersurface singularity. 相似文献
118.
Aqueous aggregates of zinc 31-hydroxy- and 31-methoxy-131-oxo-chlorins possessing a hydrophilic tetraoxyethylene chain were prepared. Zinc 31-methoxy-chlorin formed a well-ordered aggregate without intermolecular hydrogen bonding which has been widely accepted in most structural models for BChl-c, d, e aggregates in a major light-harvesting antenna of green photosynthetic bacteria, chlorosome. 相似文献
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Masayuki Koike Toru Kaji Prathuang Usaborisut Tomohiro Takigawa Akira Yoda Shozo Takahashi 《Journal of Terramechanics》2002,39(3):127-141
To investigate the soil compactibility during the cyclic loading, three different kinds of paddy field soils were prepared so as to clarify interrelationships among stress amplitude ratio, bulk density, soil water content and pore water pressure. The presetting values of specimen include the soil water content(percent dry basis) and bulk density of 25% d.b. and 1.1 Mg/m3 respectively. The relation between the number of cyclic loading and axial strain exhibited an asymptotically increasing trend, converging toward a specific value for each experimental condition. Possible effect caused by elastic–plastic characteristics could be recognized, when axial strain for 0.5 Hz excitation becomes greater than the one of 1.0 Hz under same stress amplitude ratio. When the stress amplitude ratio took 0.1, the absolute value of axial strain of 0.5 Hz was greater than the one of 1.0 Hz, whereas its decreasing trend was recognized in the sequence of silt, clay and silty sand. The qualitative relations between pore water pressure and number of cyclic loading were also examined to scrutinize the effect of effective water pressure to the soil compactibility. 相似文献