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51.
Jamie Hunter Scott Rice Robert Lowe Christopher M. Pask Stuart Warriner Visuvanathar Sridharan 《Tetrahedron letters》2017,58(46):4400-4402
2′-Hydroxyacetophenone was alkylated with a range of substituted benzyl and heteroaryl alcohols to afford the corresponding C-alkylated products in good yields under microwave irradiation. The C-alkylated products were reacted with bromoacetonitrile to afford 2-amino-3-benzyl 1,4-naphthoquinone derivatives in moderate yields. 相似文献
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V. Gopalaswamy J. A. Rice F. G. Miller 《The Journal of the Operational Research Society》1993,44(1):37-50
In recent years much emphasis has been placed on maintenance of transit vehicles. This is due to many reasons: inflation, availability of vehicles for maintenance, reliability of components etc. Many mathematical models have been developed to predict the replacement mileage of the components. These models usually focus on only one criterion for decision-making, namely the minimum replacement cost-rate. This concept tends to oversimplify the situation that is present in the system. In this research, mathematical models were developed for three criteria: (1) minimum replacement cost-rate, (2) maximum availability and (3) bottom-line component reliability. Optimum replacement plans were obtained using different multiple-criteria decision-making methods like Strictest Selection, Lexicographic and Waltz Lexicographic methods. 相似文献
54.
M.J. Rice 《Solid State Communications》1978,25(12):1083-1086
The amplitude and phase phonons and the frequency dependent conductivity below the mean-field Peierls-Fröhlich transition temperature Tc, and the Kohn anomaly and fluctuation induced charge-density-wave conductivity above Tc, are discussed on the basis of the many-phonon-coupling model recently introduced by Rice, Duke and Lipari. For dominant intramolecular phonon coupling an isotope effect in Tc is related to the isotopic shift in the small polaron binding energy. 相似文献
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We investigate the quantum fluctuations of a single atom in a weakly driven cavity, where the center of mass motion of the atom is quantized in one dimension. We present analytic results for the second order intensity correlation function g((2))(tau) and the intensity-field correlation function h(theta)(tau), for transmitted light in the weak driving field limit. We find that the coupling of the center of mass motion to the intracavity field mode can be deleterious to nonclassical effects in photon statistics and field-intensity correlations, and compare the use of trapped atoms in a cavity to atomic beams. 相似文献
58.
Hashimoto A Przybyl AK Linders JT Kodato S Tian X Deschamps JR George C Flippen-Anderson JL Jacobson AE Rice KC 《The Journal of organic chemistry》2004,69(16):5322-5327
The synthesis of the ortho- and para-e isomers in the oxide-bridged 5-phenylmorphan series of rigid tetracyclic compounds was accomplished via rac-5-(2-fluoro-5-nitrophenyl)-2-methyl-2-azabicyclo[3.3.1]nonan-9beta-ol ((+/-)-10), an intermediate containing an aromatic nitro-activated fluorine atom. The fluorine atom was used as the leaving group for the formation of the strained tetracyclic trans-fused 5,6-ring system in rac-(1alpha,4aalpha,9aalpha)-1,3,4,9a-tetrahydro-2-methyl-6-nitro-2H-1,4a-propanobenzofuro[2,3-c]pyridine ((+/-)-11), although preference for cis ring fusion during the formation of tricyclic tetra- and hexahydrodibenzofurans has been well-documented. Single-crystal X-ray crystallographic study of the desired para-e isomer ((+/-)-2), as well as of two intermediates in its synthesis, provided assurance of the correct structures. The e-isomers are among the last of the 12 oxide-bridged 5-phenylmorphans to be synthesized. We envisioned the syntheses of these rigid, tetracyclic compounds in order to determine the three-dimensional pattern of a ligand that would enable interaction with opioid receptors as agonists or antagonists. 相似文献
59.
Harding LP Jeffery JC Riis-Johannessen T Rice CR Zeng Z 《Dalton transactions (Cambridge, England : 2003)》2004,(16):2396-2397
The amide-substituted unsymmetrical ligand L(1) upon coordination to Co(2+) forms the dinuclear triple helicate [Co(2)(L(1))(3)](4+) which exists as both possible C(1) and C(3) symmetric geometric isomers in solution, however, upon addition of nitrate ions, the formation of an anion binding cavity is favoured and hence the sole product is the C(3) symmetric isomer in which all three amide substituents are hydrogen bonded to the nitrate anion. 相似文献
60.
We report results from molecular dynamics simulations of cooperative motion in a quasi-two-dimensional system of colloid particles. We find that the onset of the deviation of the single-particle displacement distribution from Gaussian form starts in the liquid phase and extends, with increasing magnitude, through the hexatic phase into the crystalline phase. The time for which the deviation is maximum increases exponentially with the density. As the density increases toward the hexatic phase a third dynamical relaxation mode emerges. We argue that the collective motion is generated by superpositions of instantaneous normal mode vibrations, with lifetimes that increase with the density, along paths with strong bond-orientation correlation. 相似文献