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851.
An electron detector system with a 3 mm × 100 mm2 Si(Li) detector with a cooled FET and vacuum air lock for changing sources was constructed. The absolute efficiency was measured as a function of energy for use in the measurement ofK conversion coefficients. With the Si(Li) and a Ge(Li) detector, theK conversion coefficient of the 320 keV transition in51V was measured to be 0.00156 ± 0.00008 where theK conversion coefficients of the 661 and 279 keV transitions in137Ba and203Tl were used as standards. From absolute detection efficiency measurements, theK conversion coefficients of the 388 and 483 keV transitions in87Sr were measured to be 0.16 ± 0.02 and 0.0024 ± 0.0003, respectively. 相似文献
852.
R. C. Hamilton J. Bennet D. Drane E. Pietrzykowski F. Seddon A. Stefancic J. Cox 《Micron (Oxford, England : 1993)》1994,25(6):613-615
The state of fimbriae type 2 (Fim 2) and fimbriae type 3 (Fim 3) preparations from Bordetella pertussis were examined by negative stain electron microscopy. Uranyl acetate induced clumping of Fim 3 regardless of pH and was unsuitable as a stain for establishing the state of fimbriae. Both ammonium molybdate and sodium phosphotungstate were able to show the differences in Fim 3 stored at pH 7.2 and pH 9.5. 相似文献
853.
A. F. Kluk D. Krmpotic J. H. Hamilton J. J. Pinajian 《Zeitschrift für Physik A Hadrons and Nuclei》1970,235(5):391-394
TheK conversion coefficients of the 388 and 483 keV transitions in87Sr populated in the decay of87Y have been measured with Ge(Li) and Si(Li) detectors by the NPG method. We find α K values of 0.162 ± 0.010 and 0.00260 ± 0.00013 for the 388 and 483 keV transitions, respectively. 相似文献
854.
855.
J. K. Deng J. H. Hamilton A. V. Ramayya W. C. Ma X. W. Zhao J. Kormicki N. Severijns L. Vanneste W. D. Hamilton P. F. Mantica Jr. H. K. Carter 《Hyperfine Interactions》1992,75(1-4):439-445
On-line nuclear orientation was performed on70As. Anisotropy data have been obtained at 8.7mK for 29 gamma transitions. Multipole mixing ratios have been extracted for
17 transitions. Our results are in good agreement with existing data for the ten previously measured transitions. Our first
time data for the 1496 keV, 2+→2+ γ-ray suggest the 2536 keV level is a good candidate for a mixed symmetry level. 相似文献
856.
857.
Z. Grabowski J. E. Thun M. S. El-Nesr W. D. Hamilton 《Zeitschrift für Physik A Hadrons and Nuclei》1962,167(1):111-122
The study of nuclear structure effects in internal conversion has been extended to the Tm169 nucleus. Gamma-gamma, electron-gamma and gamma-electron directional correlations of the 177 keV-131 keV and the 198 keV-110 keV cascades have been measured. The following results were obtained:
$$\begin{array}{l} A_2 (177\gamma - 131\gamma ) = + 0 \cdot 275 \pm 0 \cdot 007,A_4 (177\gamma - 131\gamma ) = - 0 \cdot 005 \pm 0 \cdot 016, \\ A_2 (177\gamma - 131\gamma ) = + 0 \cdot 002 \pm 0 \cdot 007, \\ A_2 (177\gamma - 131K) = + 0 \cdot 497 \pm 0 \cdot 010, \\ A_2 (198\gamma - 110\gamma ) = + 0 \cdot 295 \pm 0 \cdot 007,A_4 (198\gamma - 110\gamma ) = - 0 \cdot 013 \pm 0 \cdot 017, \\ A_2 (198K - 110\gamma ) = + 0 \cdot 001 \pm 0 \cdot 008, \\ A_2 (198\gamma - 110K) = - 0 \cdot 005 \pm 0 \cdot 006. \\ \end{array}$$ 相似文献
858.
D. H. Hamilton 《Journal d'Analyse Mathématique》1990,55(1):40-50
This research is supported in part by NSF DMS-8700627. 相似文献
859.
Robert W. Hamilton 《Journal of heterocyclic chemistry》1976,13(3):545-553
A series of tricyclic pyrazoles were prepared from intermediates available from steroid total synthesis and tested for antiarrhythmic and antiinflammatory activity. 相似文献
860.
A kinetic and mechanistic study of the autoxidation of liquid pentaerythrityl tetraheptanoate (PETH) at 180–220°C has been carried out utilizing a stirred-flow reactor. The results are consistent with the occurrence of a chain reaction scheme similar to that proposed for n-hexadecane autoxidation, namely, the formation of monohydroperoxides by the intermolecular abstraction reaction (3), the formation of α,γ- and α,δ-dihydroperoxides and α,γ- and α,δ-hydroperoxyketones by intramolecular peroxy radical abstraction reactions (4) and (4*), the bimolecular termination of peroxy radicals, reaction (6), and the rapid conversion of α,γ-hydroperoxyketones to the corresponding cleavage acids and methyl ketones, reaction (7). Comparisons of various rate parameters for the n-hexadecane and PETH systems reveal that the values of k7 and (k3/H atom)/(2 k6)1/2 are within experimental uncertainties identical for the two systems at 180°C. The proposed reaction scheme includes the concurrent formation of hydroxy radicals and hydroperoxyketone species. The results of kinetic analysis and the experimentally observed isomer distributions of primary and secondary monohydroperoxide products at high and low oxygen pressures suggest that ≈60% of the hydrogen abstractions from PETH at high oxygen pressures occur by hydroxy radicals. 相似文献