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181.
The paper argues that, until very recently, decision analysts have devoted relatively little attention to the processes of problem formulation and subjective judgement in handling ill-structured strategic decision problems. Therefore, following a brief review of existing varieties of decision analysis, a modified policy dialogue' model of decision analysis is presented which integrates decision analysis with decision aids and decision support technology. This model is developed using as an illustration strategic problems drawn from the insurance industry. The paper concludes with some suggestions for the successful application and implementation of decision analysis. 相似文献
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Richard D Chambers Darren HollingGraham Sandford Horst PuschmannJudith A.K Howard 《Journal of fluorine chemistry》2002,117(2):99-101
Direct fluorination of various quinoline derivatives in acidic reaction media gives fluorinated quinoline products arising from selective, efficient electrophilic substitution processes. 相似文献
186.
Long Chen František Hartl Howard M. Colquhoun Barnaby W. Greenland 《Tetrahedron letters》2017,58(19):1859-1862
A library of 18 conjugated, rod-like compounds with either one or two viologen residues were synthesized and characterized electrochemically. Containing up to 8 aromatic/heterocyclic rings in conjugation, the members of the library differ in the substitution pattern of electron-withdrawing or -donating groups on the aromatic substituents of the viologen units. The first and second half-wave potentials of each member were found to be linearly correlated with the calculated pKb values of the aromatic end-groups. This relationship will enable the half-wave potentials of related, novel, substituted viologen species to be predicted using a simple, empirical formula. 相似文献
187.
Stereocontrolled synthesis of (S)-Fmoc-β-nitroalanine (20) was accomplished from (R)-Fmoc-Ser(tBu)-OH (14) in a total of six steps via an oxime. The oxime (17) was obtained from (R)-Fmoc-Ser(tBu)-H (16), which in turn was obtained by reduction of Weinreb amide (15). Oxidation of oxime was realized with peroxytrifluoroacetic acid at a neutral pH at 0 °C. After removal of the tBu protecting group with 90% TFA/H2O, the hydroxyl group was oxidized with Jones reagent to afford (S)-Fmoc-β-nitroalanine (20) in overall good yield. 相似文献
188.
Max M. Abrahams Gregory W. Cushing Zachary N. Pickett William A. Howard Kraig A. Wheeler 《Journal of chemical crystallography》2010,40(7):583-590
Abstract
Mer-RhBr3(Me2pzH)3 (Me2pzH = 3,5-dimethylpyrazole) (monoclinic, P21/n, a = 8.3300 (5) Å, b = 16.2889 (9) Å, c = 15.9299 (11) Å, α = 90°, β = 100.217 (5)°, γ = 90°; V = 2,127.2 (2) Å3; Z = 4) has been characterized by X-ray diffraction, 1H and 13C nuclear magnetic resonance spectroscopy, infrared spectroscopy, and electronic absorption spectroscopy, and modeled by density functional theory (DFT) and time-dependent density functional theory (TDDFT). Mer-RhBr3(Me2pzH)3 is an octahedral complex with a HOMO → LUMO transition at 486 nm. The DFT and TDDFT calculations predicted mer-RhBr3(Me2pzH)3 to be an octahedral complex with a HOMO → LUMO transition at 540 nm. 相似文献189.
190.
We study the electrically driven spreading of dielectric liquid films in wedge-shaped gaps across which a potential difference is applied. Our experiments are in a little-studied regime where, throughout the dynamics, the electrical relaxation time is long compared to the time for charge to be convected by the fluid motion. We observe that at a critical normal electric field the hump-shaped leading edge undergoes an instability in the form of a single Taylor cone and periodic jetting ensues, after which traveling waves occur along the trailing thin film. We propose a convection-dominated mechanism for charge transport to describe the observed dynamics and rationalize the viscosity dependence of the self-excited dynamics. 相似文献