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21.
C. J. Beattie A. P. Brown M. E. Norris 《The Journal of the Operational Research Society》1971,22(1):63-75
The paper describes how a number of proposed deep-water port developments for importing ore for the British Steel Corporation were assessed. The study was divided into two stages: the first stage was used to identify the best available options against a background of uncertainty by considering one year in a changing future; the second stage was used to evaluate the best proposals in detail and plan a course of action.The investigating team was heavily involved throughout in the managerial aspects of planning and decision-making. Where appropriate the effects of this participation are described and from them corresponding lessons drawn. 相似文献
22.
In this paper we examineLF spaces, inductive limits of Fréchet spaces, in two different settings: the categoryCV S of convergence vector spaces and the categoryLC S of locally convex topological vector spaces. Special attention is given to permanence properties and retractivity properties in each case. Some interaction between properties ofLF spaces inCV S and other properties inLC S are investigated.R. Beattie's research was supported by NSERC grant OGP0005316. 相似文献
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24.
Hye Jin Lee Paul D. Beattie Brian J. Seddon Murray D. Osborne Hubert H. Girault 《Journal of Electroanalytical Chemistry》1997,440(1-2)
A polymer membrane for the selective amperometric transfer and sensing of molecular ions has been designed and characterised. The membrane was formed from two polymer layers, a supporting film of polyethylene terephthalate on which an electrolyte film containing polyvinylchloride is cast. The polyester layer has a laser-etched pattern of circular micro-holes in one region. These hole structures are arranged in a rectangular geometry and measure 22 μm in diameter with separation distances of 105 μm and 120 μm. The polyvinylchloride underlayer is a composite system comprised of a 2-nitrophenyl octyl ether plasticising solution containing an electrolytic salt of tetrabutylammonium tetrakts-(4-chlorophenyl)borate. In this way, an array of micro-interfaces between an analyte solution and a PVC gel electrolyte is formed and used as a liquid|liquid interface for the amperometric monitoring of ion transfer reactions. The membrane was characterised in terms of the voltammetric response to choline transfer. The study includes an examination of the fabrication methodology, materials composition and membrane structure. 相似文献
25.
Cuba-Chiem LT Huynh L Ralston J Beattie DA 《Langmuir : the ACS journal of surfaces and colloids》2008,24(15):8036-8044
Carboxymethyl cellulose (CMC), in solution and adsorbed on the surface of talc, has been studied with ATR FTIR spectroscopy as a function of the solution pH. The solution spectra enable the calculation of the extent of ionization of the polymer (due to protonation and deprotonation of the carboxyl group) at various pH values, yielding a value of 3.50 for the pK(app)(1/2) (pH at which half of all carboxyl groups are ionized) in a simple electrolyte solution and a value of 3.37 for the pK(app)(1/2) in solutions containing magnesium ions (3.33 x 10(-4) M). The spectra of the adsorbed layer reveal that CMC interacts with the talc surface through a chemical complexation mechanism, via the carboxyl groups substituted on the polymer backbone. The binding mechanism is active at all pH values down to pH 2 and up to pH 11. The adsorbed layer spectra reveal that protonation and deprotonation of the polymer are affected by adsorption, with an increase in the pK(app)(1/2) to a value of 4.80. Spectra of the adsorbed polymer were also acquired as a function of the adsorption time. Adsorption kinetic data reveal that the polymer most likely has two different interactions with the talc surface, with a stronger interaction with the talc edge through chemical complexation and a weaker interaction with the talc basal plane presumably through the hydrophobic interaction. 相似文献
26.
Graded radicals of graded rings 总被引:8,自引:0,他引:8
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28.
W. H. Beattie 《国际化学动力学杂志》1973,5(3):333-343
The self-radiolysis of mixtures of CO and tritium (3H2) has been studied at pressures of 0.25 to 1.0 atmospheres, temperatures of ?198° to +100°C, and in the presence of added H2O or CO2. The products of decomposition are CO2, 3H2O, C3H4, C23H4, and a white polymer believed to be polyformaldehyde. Initial rates and G values were measured and compared with rates of ion pair formation. The rates of formation of both CO2 and C3H4 are independent of temperature and proportional to the energy absorbed in the 3H2. 相似文献
29.
I.R. Beattie J.B. Brown S. Firth R.D. Gordon T.R. Gilson P.J. Jones M.R. Levy K.R. Millington S.J. Williams 《Chemical physics letters》1984,108(2):138-140
We habe obtained part of the laser-induced fluorescence spectrum of chromyl fluoride in a free jet expansion at an instrumental resolution of better than 0.001 cm?1. This spectrum (together with that of the dispersed fluorescence) allows the identification of the (0,0) band or the absorption spectrum and of several progressions in the lowest bending frequency. 相似文献
30.
Uranium (VI) chloride fluorides were synthesized by the reaction of liquid HCl and solid UF6 between −80 and −114°C. These dark red compounds are unstable above −40 to −60°C. The simplest formulas derived from compositional analysis are UF5Cl and UF4Cl2. 相似文献