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131.
F. Mattiocco M. Carter 《International Journal of Infrared and Millimeter Waves》1995,16(12):2249-2255
An extension to a 20 GHz HP8510C Network Analyzer has been built for wideband measurements between 80 and 360 GHz. Improvements relative to the first version [1], [2] include new harmonic mixers, and an active doubler. Dynamic ranges up to 60 dB in transmission and 50 dB in reflection are obtained up to 280 GHz, with more than 50 GHz instantaneous bandwidth using waveguide calibration. Detection with a 30 dB dynamic range is obtained at 320 – 360 GHz. Time domain measurements give spatial resolution down to 2 mm. 相似文献
132.
H. A. Schuessler E. C. Benck F. Buchinger H. Iimura Y. F. Li C. Bingham H. K. Carter 《Hyperfine Interactions》1992,74(1-4):13-21
The nuclear moments of the neutron-deficient187,188Tl isotopes were determined by measuring the hyperfine structure splittings of the λ=535 nm line in neutral thallium. An optical
efficiency of 2×10−4 photons per radioactive ion was achieved using collinear fast beam laser spectroscopy with a large solid angle fiber optical
array detector. Most of the moments can be interpreted fairly well in the single particle model. 相似文献
133.
134.
Muse Oke RosalindTanYan Ching LesterG. Carter KennethA. Johnson Huanting Liu StephenA. McMahon MalcolmF. White Carlos Bloch CatherineH. Botting MartinA. Walsh AishahA. Latiff MalcolmW. Kennedy Alan Cooper JamesH. Naismith 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2008,120(41):7971-7974
135.
A.C. Carter G.P. Carver R.J. Nicholas J.C. Portal R.A. Stradling 《Solid State Communications》1977,24(1):55-60
The intensities of the bound to bound transitions of the shallow donors in silicon and CdTe are found to be strongly electric field dependent when observed by photoconductivity techniques at low temperatures. Under these conditions significant differences can be detected between the photoconductive spectrum and the same transitions observed in absorption. The photoconductive peaks are shifted consistently to lower frequency compared with the absorption spectrum and additional peaks appear which are not significant features in absorption. These additional peaks are believed to result from the formation of molecular complexes of donors. The strong electric field dependence of the bound transitions observed in photoconductivity, the shift to lower frequency of the peaks and the enhancement of the additional lines can all be explained qualitatively on the assumption that the mechanism responsible for the generation of the photosignal involves hopping between the excited states of the molecular complexes 相似文献
136.
C.P. Bust J.R. Carter W.W. Neale J.G. Rushbrooke D.R. Ward R.E. Ansorge B.Y. Oh M. Pratap G. Sionakides G.A. Smith J. Whitmore R. Raja L. Voyvodic 《Nuclear Physics B》1978,140(3):409-422
We have investigated the reactions . The final state is dominated by diffractive production of a system which shows a strong tendency to form . The process is also observed in this reaction, indicating an energy dependence of s?1.5±0.1. The channel shows less single diffraction, and has a doubly diffractive component consistent with pomeron factorization. Strong Δ++(Δ++) production is agoain seen, but in contrast to the channel we also observe considerable ?0 production. 相似文献
137.
R.E. Ansorge J.R. Carter R.P. Mount W.W. Neale R. Raja J.G. Rushbrooke 《Nuclear Physics B》1975,97(3):439-444
We present data on the inclusive neutron spectra produced in the forward direction by the interactions of 23.85 GeV/c protons in a copper target. The results are in good agreement with the predictions of the triple-Regge model. 相似文献
138.
The oxidation of the adsorbed π-allyl (η3-C3H5), prepared on atomic oxygen- and hydroxyl-covered Ag(110) by dissociation of allyl chloride (C3H5Cl), is investigated with temperature-programmed desorption and high-resolution electron energy loss spectroscopy. Allyl chloride adsorbs molecularly on oxygen-covered Ag(110) at 110 K. Upon heating to 180 K, some allyl chloride dissociates to form π-allyl and atomic chlorine, and the remainder desorbs molecularly. The π-allyl undergoes combustion to form hydroxyl or carbonate until all of the free oxygen is consumed by 200 K. Migratory insertion of hydroxyl into excess π-allyl commences near 220 and finishes by 250 K, forming adsorbed allyl alcohol (C3H5OH), which reacts either with excess hydroxyl near 240 K to form allyl alkoxy (η1(O)-C3H5O) and water, or with π-allyl at 250 K to form allyl alkoxy and propylene (C3H6). Th allyl alkoxy evolves acrolein (C3H4O) by β-hydrogen elimination near 285 K, and propylene is evolved concurrently as the hydrogen released by this reaction rapidly scavenges π-allyl. Finally, the remaining π-allyl dimerizes to form 1,5-hexadiene (C6H10), which desorbs at 315 K. The gross observations of reaction pathways and temperatures are used to evaluate important aspects of the thermochemistry of these reactions. 相似文献
139.
S.F. Biagi M. Bourquin A.J. Britten R.M. Brown H. Burckhart A.A. Carter J.R. Carter Ch. Doré P. Extermann M. Gailloud C.N.P. Gee W.M. Gibson J.C. Gordon R.J. Gray P. Igo-Kemenes W.C. Louis T. Modis P. Mühlemann R. Weill 《Physics letters. [Part B]》1982,112(3):277-280
From a sample of 735 000 Ξ? decays, we have obtained a new upper limit for the branching ratio . The result is 1.9 × 10?5 at the 90% confidence level. 相似文献
140.
J. Carter R.G. Clarkson V. Hnizdo R.J. Keddy D.W. Mingay F. Osterfeld J.P.F. Sellschop 《Nuclear Physics A》1976,273(2):523-532
Angular distributions for 16O + 24Mg and 12C + 24Mg elastic and inelastic (2+, 1.37 MeV state in 24Mg) scattering have been measured at energies spanning the Coulomb barrier. Apart from the structure typical of strong destructive Coulomb-nuclear interference, the data exhibit some additional specific features. Coupled channel calculations were performed, along with DWBA calculations to analyse the data using fixed coupling strengths deduced from the results of Coulomb excitation work. The importance of higher-order effects such as reorientation, is demonstrated. 相似文献