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121.
Molar extinction coefficients of some carbohydrates viz. l-arabinose (C5H10O5), d-glucose (C6H12O6), d-mannose (C6H12O6), d-galactose (C6H12O6), d(-) fructose (C6H12O6) and maltose (C12H24O12) in aqueous solutions have been determined at 81, 356, 511, 662, 1173 and 1332 keV by gamma ray transmission method in a
narrow beam good geometry set-up. These coefficients have been found to depend upon the photon energy following a 4-parameter
polynomial. These extinction coefficients for different sugars having the same molecular formula have same values varying
within experimental uncertainty. Within concentration ranges studied, Beer-Lambert law is obeyed very well. 相似文献
122.
123.
The diffusion of110Ag in Cu2O has been measured by a serial-sectioning technique as a function of temperature (700–1132°C) and oxygen partial pressure (6 × 10?6 ?8 × 10?2 atm). The data are fit to the defect model for Cu2O developed by the authors in the preceding paper. Silver ions have a larger impurity-vacancy binding free energy and/or a larger jump frequency for the singly charged cation vacancies relative to that for the neutral cation vacancies. The activation enthalpies for the diffusion of copper and silver ions in Cu2O are nearly equal, but the absolute value of D1Ag is about three times larger than D1Cu even though the silver ion is 31% larger than the copper ion. 相似文献
124.
125.
The diffusion of 59Fe and 60Co has been measured in pure CoO and dilute iron-doped CoO, (Co1?cFecO, as a function of temperature (1000–1400°C) and oxygen partial pressure Po2), (10?7 ≦ Po2 ≦ 0 21 atm) The enhancement factors for the diffusivities of iron and cobalt are nearly identical, which suggests that the primary cause of the enhancement is the increased concentration of charge-compensating cation vacancies with the addition of iron. The Fe ions dissolved in CoO appear to exist as a mixture of Fe2+ and Fe3+ ions, the fraction of iron ions in the three-plus state decreases with decreasing Po2 The simultaneous diffusion of 52Fe and 59Fe has been measured as a function of (itpo; at 1200°C The correlation factor for Fe impurity diffusion determined from the isotope-effect measurements is about the same as that for self-diffusion in CoO at high (itPo2 (2 × 10?3 ≦ po2 ≦ 0 21 atm), but increases slightly with decreasing pO2 Both the enhancement-effect and isotope-effect experiments suggest that the nearestneighbor interactions between Fe ions and vacancies is small, and that the dissolved Fe ions do not have strongly bound electron holes. 相似文献
126.
127.
M.R. Jane P. Grannis B.D. Jones N.H. Lipman D.P. Owen V.Z. Peterson W.T. Toner E.H. Bellamy M.G. Green J. Kirkby C.M. Solomonides J.A. Strong D.H. Thomas 《Physics letters. [Part B]》1975,59(1):99-102
We have looked for the decay η → π0e+e? in an optical spark chamber experiment at the Rutherford Laboratory. Our observations are consistent with no events being seen and give an upper limit rate (η → π0e+e?)/ rate (η → all) < 4.5 × 10?5 (90% C.L.). 相似文献
128.
129.
M.R. Jane P. Grannis B.D. Jones N.H. Lipman D.P. Owen V.Z. Peterson W.T. Toner E.H. Bellamy M.G. Green J. Kirkby C. Solomonides J.A. Strong D.H. Thomas 《Physics letters. [Part B]》1975,59(1):103-105
In an optical spark chamber experiment we have obtained a sample of 80 eta Dalitz decays (η → e+e?γ) and have measured the eta electromagnetic form factor to be F(X) = 1.0?(0.22 ±0.45)X, where X=Mee2/Mη2, and the branching ratio (η→e+e?γ/(η→π+π?π0)= (0.0082 ± 0.0020). 相似文献
130.
S. A. Dickey J. J. Kraushaar R. J. Peterson 《Zeitschrift für Physik A Hadrons and Nuclei》1985,320(4):649-654
Inelastic scattering of 35 MeV alpha particles from7Li was used to induce the five known inelastic excitations. A collective coupled channel analysis yielded deformations for each transition and isoscalar quadrupole reduced transition rates were determined for each. The strong-coupling rotational model was found to agree closely with the results for the states associated with the ground state band, but the higher states are excited mainly by a two-step mechanism. 相似文献