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71.
M.E. Williams T.H. Kruse P. Goode F.T. Baker J.L. Matthews W. Savin 《Nuclear Physics A》1973,213(2):317-331
Differential cross sections have been measured for 41(d, t)40K and 41K(p, d)40K at 15 MeV using a magnetic spectrograph with electronic detection by proportional-counter-scintillator telescopes or semiconductor detectors. Knowledge of the structure of the 40K multiplets () and () permits the determination of amplitudes and relative phases for various configurations and neutron correlations in the 41K ground state. Spectroscopic factors for neutron pick-up to states in 40K are strongly influenced by the interference of transition amplitudes. In the (d, t) reaction T= 1, 2p-2h states are also observed. 相似文献
72.
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74.
John P. Matthews 《The Journal of the Operational Research Society》1988,39(12):1155-1161
The economic lot-scheduling problem for the single-machine, n-item scheduling problem has received attention in a number of journals. One approach is to define a sequence (called the fundamental cycle) in which every item is made at least once, and then to determine the length of production runs consistent with the aggregate inventory level which will maximize the length of the cycle duration. The assumption that production is switched from one item to the next only when the inventory level of the latter reaches zero is often used in heuristic solutions to these models. This paper illustrates the conditions in which the ‘zero-switch’ rule is a necessary condition at the optimal solution for situations in which demand is continuous and production capacity equals aggregate demand. 相似文献
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76.
F. Dibianca R.L. Eisner W. Fickinger J.A. Malko D. Matthews J. OReilly J.F. Owens D.K. Robinson S.U. Chung S.D. Protopopescu 《Physics letters. [Part B]》1976,63(4):461-465
Data are presented on the reactions π+n → ?0+X and , respectively. Comparisons are made with related reactions at higher energies. 相似文献
77.
The negative ion mass spectra of highly fluorinated molecules with varying functionality are discussed. Attempts to obtain negative molecular ions where no positive molecular ion was observed met with little success. An interesting structural correlation for fluorinated ethers was developed based upon the observation of the abundant perfluoro alkoxide anions, CF3O? and CF3(CF2)2O?, in the negative ion mass spectrum. 相似文献
78.
Matthews JR Goldoni F Schenning AP Meijer EW 《Chemical communications (Cambridge, England)》2005,(44):5503-5505
The non-aggregating nature of a water-soluble pi-conjugated polythiophene has been characterised by concentration independent thermal denaturing. 相似文献
79.
Marshall LJ Williams JR Almond MJ Atkinson SD Cook SR Matthews W Mortimore JL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(1-2):233-241
Three ochre samples (A (orange-red in colour), B (red) and C (purple)) from Clearwell Caves, (Gloucestershire, UK) have been examined using an integrated analytical methodology based on the techniques of IR and diffuse reflectance UV-visible-NIR spectroscopy, X-ray diffraction, elemental analysis by ICP-AES and particle size analysis. It is shown that the chromophore in each case is haematite. The differences in colour may be accounted for by (i) different mineralogical and chemical composition in the case of the orange ochre, where higher levels of dolomite and copper are seen and (ii) an unusual particle size distribution in the case of the purple ochre. When the purple ochre was ground to give the same particle size distribution as the red ochre then the colours of the two samples became indistinguishable. An analysis has now been completed of a range of ochre samples with colours from yellow to purple from the important site of Clearwell Caves. 相似文献
80.