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91.
A computer-based method is developed to perform the numerical analysis of the measured adsorption isotherm in order to determine the quantitative distribution of potential energies displayed by a solid substrate for a physically-adsorbed gas. The characteristic adsorptive energies of the basal planes of graphite and of boron nitride for argon and nitrogen are determined as examples of the use of the method. As more such values are put on record the method becomes suitable for the qualitative analysis of substrates. 相似文献
92.
G. Ransoné P. Sixel H.H. Kaufmann R. Klein H. Vogt H. Dreverman D. Kuhn J.P. Porte R.T. Ross F. Triantis K. Dziunikowska B. Muryn K.W.J. Barnham J. Wells P.R.S. Wright D. Dallman F. Mandl M. Szczekowski 《Nuclear Physics B》1980,167(3):285-291
The charged multiplicity distribution is presented for K?p interactions produced in the hydrogen bubble chamber, BEBC, using an r.f. separated, tagged K? beam of 110 GeV/c momentum. A comparison with K+p, πp and pp data at lower energies shows that the main features of the multiplicity distributions depend on energy and charge of the incident particles, but not on their strangeness. At high energies, only the energy is important. 相似文献
93.
Ulrich Ross 《Chemical physics letters》1983,99(1):71-76
The energy loss of 7Li+ ions scattered from NO has been measured in a molecular beam experiment over a range of scattering angles (θlab = 6.0–30.0°) at Ec.m. = 7 cV. The vibrational/rotational energy transfer behaves similar to the previously reported study on 7Li+CO, suggesting that in NO the degeneracy of the electronic ground state has little effect. 相似文献
94.
95.
Sawtooth faceting in silicon nanowires 总被引:1,自引:0,他引:1
We observe in situ the vapor-liquid-solid (VLS) growth of Si nanowires, in UHV-CVD using Au catalyst. The nanowire sidewalls exhibit periodic sawtooth faceting, reflecting an oscillatory growth process. We interpret the facet alternation as resulting from the interplay of the geometry and surface energies of the wire and liquid droplet. Such faceting may be present in any VLS growth system in which there are no stable orientations parallel to the growth direction. The sawtooth structure has important implications for electronic mobility and scattering in nanowire devices. 相似文献
96.
Melting curves of Cu and Ni were measured in the laser-heated diamond cell to 97 GPa (3800 K) and 60 GPa (2970 K), respectively. The temperatures of Cu are in good agreement with recent theoretical calculations. The Cu melting slope (dT/dP) is about 2.5 times steeper than for Ni. The present results confirm the key role d-shell electrons play in determining the temperature dependence of high pressure melting curves in transition metals that have filled or partially filled d electron bands. 相似文献
97.
Ledieu J Hoeft JT Reid DE Smerdon JA Diehl RD Lograsso TA Ross AR McGrath R 《Physical review letters》2004,92(13):135507
An ultrathin film with a periodic interlayer spacing was grown by the deposition of Cu atoms on the fivefold surface of the icosahedral Al70Pd21Mn9 quasicrystal. For coverages from 5 to 25 monolayers, a distinctive quasiperiodic low-energy electron diffraction pattern is observed. Scanning tunneling microscopy images show that the in-plane structure comprises rows having separations of S=4.5+/-0.2 A and L=7.3+/-0.3 A, whose ratio equals tau=1.618... within experimental error. The sequences of such row separations form segments of terms of the Fibonacci sequence, indicative of the formation of a pseudomorphic Cu film. 相似文献
98.
Ross DA Olson IR Marks LE Gore JC 《The Journal of the Acoustical Society of America》2004,116(3):1793-1799
The ability to identify and reproduce sounds of specific frequencies is remarkable and uncommon. The etiology and defining characteristics of this skill, absolute pitch (AP), have been very controversial. One theory suggests that AP requires a specific type of early musical training and that the ability to encode and remember tones depends on these learned musical associations. An alternate theory argues that AP may be strongly dependent on hereditary factors and relatively independent of musical experience. To date, it has been difficult to test these hypotheses because all previous paradigms for identifying AP have required subjects to employ knowledge of musical nomenclature. As such, these tests are insensitive to the possibility of discovering AP in either nonmusicians or musicians of non-Western training. Based on previous literature in pitch memory, a paradigm is presented that is intended to distinguish between AP possessors and nonpossessors independent of the subjects' musical experience. The efficacy of this method is then tested with 20 classically defined AP possessors and 22 nonpossessors. Data from these groups strongly support the validity of the paradigm. The use of a nonmusical paradigm to identify AP may facilitate research into many aspects of this phenomenon. 相似文献
99.
Micro-sized void spheres are successfully generated in a solid polymer by use of a tightly focused femtosecond laser beam from a high-repetition-rate laser oscillator. Confocal reflection images show that the void spheres are longitudinal rotational symmetric ellipsoids with a ratio of long to short axes of approximately 1.5. Layers of void spheres are then stacked to create three-dimensional diamond-lattice photonic crystals. Three gaps are observed in the [100] direction with a suppression rate of the second gap of up to approximately 75% for a 32-layer structure. The observed first- and second-order gaps shift to longer and shorter wavelengths, respectively, as the angle of incidence increases. 相似文献
100.
Reetz MT Tielmann P Eipper A Ross A Schlotterbeck G 《Chemical communications (Cambridge, England)》2004,(12):1366-1367
The throughput of a previously described NMR-based -assay has been increased by a factor of at least 4 as a consequence of adapting the system to chemical shift imaging; by using a 19-capillary system the enantiomeric purity of 5600 samples can be measured per day. 相似文献