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31.
32.
F. Herrera S. Alonso F. Chiclana E. Herrera-Viedma 《Fuzzy Optimization and Decision Making》2009,8(4):337-364
Computing with Words (CW) methodology has been used in several different environments to narrow the differences between human
reasoning and computing. As Decision Making is a typical human mental process, it seems natural to apply the CW methodology
in order to create and enrich decision models in which the information that is provided and manipulated has a qualitative
nature. In this paper we make a review of the developments of CW in decision making. We begin with an overview of the CW methodology
and we explore different linguistic computational models that have been applied to the decision making field. Then we present
an historical perspective of CW in decision making by examining the pioneer papers in the field along with its most recent
applications. Finally, some current trends, open questions and prospects in the topic are pointed out. 相似文献
33.
A five-coordinate, ligand-stabilised alkynenickel carbonyl complex (III), in which bond formation between carbon monoxide and the alkyne does not occur, is formed by reaction of (bipy)ni(CO)2 (I) with phenylacetylene. The products (V and VII) from the reactions of III with carbon monoxide or t-butylisonitrile are described and characterised. A reaction scheme for the nickel-induced CC-bond formation between alkynes and carbon monoxide is discussed. 相似文献
34.
35.
F.J. López Herrera 《Tetrahedron letters》1980,21(51):4963-4966
The products of the Knoevenagel reaction between methyl acetoacetate and aldehydopentoses undergo various cyclisation processes when treated with trifluoroacetic acid in aprotic solvents which are controlled by the sugar configuration at C-2 and C-3. 相似文献
36.
L.?Herrera G.?Magli D.?MalafarinaEmail author 《General Relativity and Gravitation》2005,37(8):1371-1383
A new, globally regular model describing a static, non spherical gravitating object in General Relativity is presented. The model is composed by a vacuum Weyl–Levi-Civita special field – the so called gamma metric – generated by a regular static distribution of mass-energy. Standard requirements of physical reasonableness such as, energy, matching and regularity conditions are satisfied. The model is used as a toy in investigating various issues related to the directional behavior of naked singularities in static spacetimes and the black hole (Schwarzschild) limit. 相似文献
37.
Dessole G Bernardi L Bonini BF Capito E Fochi M Herrera RP Ricci A Cahiez G 《The Journal of organic chemistry》2004,69(24):8525-8528
A straightforward procedure for the regio- and stereoselective synthesis of alpha-hydrazino ketones is described. Manganese enolates and manganese enamines derived from ketones and from the corresponding N-sulfinylimines react with azodicarboxylate esters (DTBAD and DEAD) in a regioselective fashion to afford in good to excellent yields the kinetic alpha-hydrazino ketones as sole or highly prevalent products. When enantiopure N-sulfinyl manganese enamines were used the stereoselectivity of these reactions ranged from 40% to 68% ee. 相似文献
38.
Aitala EM Amato S Anjos JC Appel JA Ashery D Banerjee S Bediaga I Blaylock G Bracker SB Burchat PR Burnstein RA Carter T Carvalho HS Copty NK Cremaldi LM Darling C Denisenko K Devmal S Fernandez A Fox GF Gagnon P Gobel C Gounder K Halling AM Herrera G Hurvits G James C Kasper PA Kwan S Langs DC Leslie J Lundberg B Magnin J Massafferri A MayTal-Beck S Meadows B de Mello Neto JR Mihalcea D Milburn RH de Miranda JM Napier A Nguyen A d'Oliveira AB O'Shaughnessy K Peng KC Perera LP Purohit MV 《Physical review letters》2001,86(5):770-774
From a sample of 1172 +/- 61 D(+)-->pi(-)pi(+)pi(+) decays, we find gamma(D(+)-->pi(-)pi(+)pi(+))/gamma(D(+)-->K-pi(+)pi(+)) = 0.0311 +/- 0.0018(+0.0016)(-0.0026). Using a coherent amplitude analysis to fit the Dalitz plot of these decays, we find strong evidence that a scalar resonance of mass 478(+24)(-23) +/- 17 MeV/c(2) and width 324(+42)(-40) +/- 21 MeV/c(2) accounts for approximately half of all decays. 相似文献
39.
Antonio Herrera Nazario Martín Rachid Chioua Ángel Sánchez-Vázquez John Almy 《Tetrahedron》2009,65(8):1697-2715
Two alternative methods for the preparation of new pyrimidine Diels-Alder cycloadducts from the readily available 2,4-bis(methylsulfanyl)-5,6-dihydrocyclobuta[d]pyrimidine are presented. In the first method, the in situ generated pyrimidine ortho-quinodimethane reacts with various dienophiles to form the respective cycloadducts bearing two methylthio groups, which can be easily replaced by other functional groups. In the second method, one or both of the methylsulfanyl groups of the starting pyrimidine are replaced first and the resulting functionalized pyrimidines are able to undergo Diels-Alder cyclization with different dienophiles to form pyrimidine cycloadducts. These alternative synthetic strategies provide access to a wide variety of pyrimidine cycloadducts with a different substitution pattern on the pyrimidine ring. Yield data indicate that the electronic nature of the functional groups strongly influence the efficiency of the cycloaddition reaction. 相似文献