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51.
L-L. Andersson D. Rudolph J. Ekman C. Fahlander E. K. Johansson R. du Rietz C. J. Gross P. A. Hausladen D. C. Radford G. Hammond 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):381-390
The 61
30Zn31 isotope has been produced at the Oak Ridge National Laboratory in the fusion-evaporation reaction 40Ca(24Mg, 2pn)61Zn at 104MeV. The experimental set-up allowed γ-rays to be detected in the CLARION Ge detector array in coincidence with the
detection of recoiling nuclei in the focal plane at the end of the recoil mass spectrometer. This provides a unique identification
of γ-rays belonging to 61Zn. The excited states have been explored by means of recoil- γγ coincidences, and the resulting decay scheme comprises almost
70 transitions. The data reveal numerous non-yrast states and suggest a revised spin and parity assignment for a previously
observed superdeformed band. The resulting decay scheme is compared to predictions from different sets of large-scale shell
model calculations. 相似文献
52.
Charles Hammond Graham J. Hutchings David J. Willock Stuart H. Taylor 《Research on Chemical Intermediates》2003,29(7-9):911-920
The activation of CH4 has been probed by studying CH4 oxidation at ambient pressure over gallium- and zinc-based catalysts prepared by precipitation and modified with Au and Pt. The unmodified gallium- and zinc-based catalysts were both active for CH4 oxidation. Modification of these catalysts by the addition of Au and Pt, alone and in combination significantly increased the rate of CH4 oxidation. The 1% Pt/Ga2O3 catalyst was the most active of the gallium-based systems. The addition of Au to ZnO markedly increased the activity compared with unmodified ZnO, whilst for Au in combination with Pt the activity was further enhanced due to a synergistic effect of the metals. 相似文献
53.
We study a model of mass-bearing coagulating planar Brownian particles. The coagulation occurs when two particles are within a distance of order ε. We assume that the initial number of particles N is of order |logε|. Under suitable assumptions of the initial distribution of particles and the microscopic coagulation propensities, we show that the macroscopic particle densities satisfy a Smoluchowski-type equation. 相似文献
54.
55.
Enzymatic reactions in supercritical gases 总被引:10,自引:0,他引:10
D. A. Hammond M. Karel A. M. Klibanov V. J. Krukonis 《Applied biochemistry and biotechnology》1985,11(5):393-400
The enzyme polyphenol oxidase has been found to be catalytically active in supercritical carbon dioxide and fluoroform: it
readily oxidizesp-cresol andp-chlorophenol to their correspondingo-benzoquinones. 相似文献
56.
Hammond P. R. Fletcher A. N. Bliss D. E. Henry R. A. Atkins R. L. Moore D. W. 《Applied Physics A: Materials Science & Processing》1976,9(1):67-70
A potential new class of “monocyclic” lasing dyes is discussed and four families out of nine within the class are examined.
The 2,6-diaminopyridines in acid are found to lase under flashlamp excitation but show low slope efficiencies and lower stabilities
than the “bicyclic” dyes described previously. Other, miscellaneous dyes show oxygen quenching of laser action rather than
enhancement and the best of these produces short pulses under long pulse excitation.
This study was supported under contract SANL 284 from the Lawrence Livermore Laboratory. 相似文献
57.
A novel method for modelling rough surfaces as the output of linear filters operating on white noise in the spatial domain is proposed. These “systems” models may then be utilized in certain analytical methods proposed by the authors, which are not described herein but have been reported in full elsewhere [1, 2] to calculate the non-stationary response of vehicles moving on rough ground with variable velocity. Either time variable covariance or evolutionary spectra of response may be obtained by the method. Here, justification is provided for the use of such models and a method of estimating their parameters via Maximum Entropy Spectral Analysis—a method well suited to this particular problem—is discussed. 相似文献
58.
Girolamo A. Ortolano R. C. Stuart Kenneth R. Wunschel Jr. Edward A. Kaiser Rupert P. Hammond Alvin K. Swonger 《Microchemical Journal》1983,28(3):409-430
The method described here may be used for the determination of serum ionized calcium. The physical conditions of the measurement, including sample volume (0.6 ml) and temperature (25 or 37 °C), are fixed. Stasis of the sample may contribute to a prolonged but not prohibitive response time. Other than the prolonged response time, the performance characteristics of the electrodes were not altered by incorporating them into the electrode chamber. Exemplifying the utility of this method were the results of protein-binding studies, in vitro and ex vivo CaCl2 and EDTA administration and a comparison with the Orion SS-20. In consideration of the data presented, the cost and simplicity of construction, and method described should serve to make the determination of serum ionized calcium accessible to a greater number of investigators and encourage research in pharmacological and physiological processes thought to be mediated by serum ionized calcium. 相似文献
59.
W H Okamura M L Hammond A Rego A W Norman R M Wing 《The Journal of organic chemistry》1977,42(13):2284-2291
60.
P. R. Hammond A. N. Fletcher R. A. Henry R. L. Atkins 《Applied Physics A: Materials Science & Processing》1975,8(4):315-318
Two new families of lasing dyes, the 8-azacoumarins and the 8-azaquinolones are described and are found to operate blue-shifted
from the coumarins and quinolones. Like the quinolones, they have higher thresholds and lower slope efficiencies than the
coumarins. All have yielded long output pulses on long pulse excitation.
This study was supported under contract SANL 284 from the Lawrence Livermore Laboratory. 相似文献