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1.
T. C. Griffith 《Hyperfine Interactions》1994,89(1):3-17
The major steps in the evolution of techniques for producing positron beams of well defined energies over the last 25 years are reviewed. Developments in the methods of using these beams for experiments in atomic physics are then traced historically 相似文献
2.
3.
Meghan Griffith 《Acta Analytica》2007,22(1):16-28
In this paper, I argue that trying is the locus of freedom and moral responsibility. Thus, any plausible view of free and
responsible action must accommodate and account for free tryings. I then consider a version of agent causation whereby the
agent directly causes her tryings. On this view, the agent is afforded direct control over her efforts and there is no need
to posit—as other agent-causal theorists do—an uncaused event. I discuss the potential advantages of this sort of view, and
its challenges. 相似文献
4.
Novel mixed valence states have been obtained by the treatment of cobaltous ferrocyanides (Co+2FeII) and ferricyanides (Co+2FeIII) in an ozone flow. The CN stretching bands occur at 2085 cm–1 for Co+2FeII and at 2160 cm–1 for Co+2FeIII. After the ozonization process of Co+2FeII, an intense band approximately at 2125 cm–1 is detected. This intermediate band must correspond to a mixed valence state of the type: FeII–CN–Co2+–NC–FeIII Mössbauer spectra recorded in situ during the ozonization of Co+2FeII show the presence of two components: a doublet with isomer shift and quadrupole splitting values close to the cobalti ferricyanide and a very broad line for the mixed valence state. From the Mössbauer and infrared spectra of the aged samples of the Co+2FeII after ozonization, a relaxation process to the initial state of the samples is observed but the mixed valence state is stable. 相似文献
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6.
J. Griffith R. J. Rosenberg O. Díaz-Rizo E. González 《Journal of Radioanalytical and Nuclear Chemistry》1996,213(1):71-78
Thermal and epithermal non-destructive activation analyses have been performed on samples of final molasses from 14 different sugar factories, covering the most important regions in Cuba. From the first measurement after irradiation at the Triga Mark reactor (VTT), the concentration of more than 15 elements is reported. The almost constant elemental composition shows that they can be used equally for different purposes as animal foodstuff and for the manufacture of biotechnological products. This work is part of a research project developed in order to establish a complete characterization of Cuban sugar molasses. 相似文献
7.
8.
The vibrational spectra of a number of transition-metal complexes containing terminal or bridging nitrido (N3?) and oxo (O2?) ligands are reported. Full assignments of fundamental modes are given for (OsO314N)?, (OsO315N)?, (Os14NX4)?, (Os15NX4)?, (Ru14NX4)?, (Os14NX5)2?, (Os15NX5)2? and (Ru14NX5)2? (X = Cl, Br), and also for the oxo complexes (Mo16OCl4, (Mo18OCl4)?, (Mo16OCl5)2? and (Mo18OCl5)2?. Force constants have been evaluated for the four- and five-coordinate complexes. The significance of the results is discussed in terms of the metalligand bonding involved in these species. 相似文献
9.
Griffith GA Percy JM Pintat S Smith CA Spencer N Uneyama E 《Organic & biomolecular chemistry》2005,3(15):2701-2712
Highly-functionalised difluorinated cyclooctenones were synthesised from trifluoroethanol using either metallated difluoroenol acetal or carbamate chemistry, followed by a [2,3]-Wittig rearrangement or aldol reaction. Efficient RCM reactions afforded the title compounds which showed rather restricted fluxional behaviour by VT (19)F NMR. Topological characterisation by molecular modelling and NOESY/ROESY experiments offered a number of challenges, but allowed the identification of two favoured boat-chair conformers which interconverted by pseudorotation with relatively large activation barriers. 相似文献
10.
van den Brand JF Ent R Anthony PL Arnold RG Arrington J Beise EJ Belz JE Bosted PE Bulten H Chapman MS Coulter KP Dietrich FS Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney ER Kuhn S Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH van Bibber K Wasson DA White JL Zeidman B 《Physical review D: Particles and fields》1995,52(9):4868-4871