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161.
Mills Dean III 《Experimental Mechanics》1977,17(8):303-307
New materials and techniques are described for using vulcanized rubber to protect strain gages installed on the components of a controllable-pitch propeller (CPP) system of a Navy destroyer. Strain gages protected by vulcanized rubber have survived many months of full-scale sea trials of the CPP system. 相似文献
162.
The nitrogen 1s binding energy of nitric oxide adsorbed on nickel oxide, cobalt oxide and graphite was measured at several temperatures by X-ray photoelectron spectroscopy. For the oxides, a temperature dependent range of binding energies was observed, but for graphite the nitrogen 1s binding energy was independent of temperature. The values obtained suggest that significant back donation of electrons occurs from the oxides to the adsorbed nitric oxides, but no back donation occurs from graphite to adsorbed nitric oxide. However, adsorption did not cause changes in the binding energy of substrate core electrons. It is believed that unless the mean free path of electrons is short, the total photoelectron signal will not reveal changes in binding energy of electrons from substrate atoms at the surface. 相似文献
163.
A. Fraefel J. Seibl Noel W. Davies John C. Bignall Ross W. Lincolne Jaime Espinosa Gonzalez Hans-Friedrich Grützmacher C. Lifshitz M. Goldenberg Y. Malinovich M. Peres Gerhard Holzmann Gernot Frenking Bernd Steiner Gary Caldwell John E. Bartmess Klaus Eckart Helmut Schwarz Shinjiro Kobayashi Hiroshi Taniguchi Helmut Schwarz Klaus Eckart Lester C. E. Taylor 《Journal of mass spectrometry : JMS》1982,17(9):448-460
164.
June A. Lester 《Aequationes Mathematicae》1996,52(1):215-245
Summary This paper is the second in a series of three examining Euclidean triangle geometry via complex cross ratios. In the first paper of the series, we examined triangle shapes. In this paper, we coordinatize the Euclidean plane using cross ratios, and use these triangle coordinates to prove theorems about triangles. We develop a complex version of Ceva's theorem, and apply it to proofs of several new theorems. The remaining paper of this series will deal with complex triangle functions. 相似文献
165.
166.
Lester A. Rubenfeld William E. Warren 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1971,22(5):931-937
Zusammenfassung Diese Mitteilung behandelt eine vollständige Bewertung der Spannungs-Singularität am Rande eines flachen kreisförmigen Spaltes unter der Einwirkung von Elektrostriktion. Die Ergebnisse bestätigen die Schlussfolgerungen, welche früher bei zweidimensionalen Problemen gezogen wurden.Die der Elektrostriktion zuzuschreibende Singularität zeitigt eine rein radiale Spannung, welche nicht dazu neigt, die schon bestehenden Spalten ihrer Ausdehnungs-Oberfläche entlang auszubreiten.
Research supported by the National Science Foundation under grant NSF GP 22567.
Research supported by the United States Atomic Energy Commission. 相似文献
Research supported by the National Science Foundation under grant NSF GP 22567.
Research supported by the United States Atomic Energy Commission. 相似文献
167.
168.
The adaptation of the lattice-gas model to embody features possessed by water is further explored. On the basis of Martin's functional derivative formulation of Ising problems, a perturbation scheme is developed which allows calculation of the free energy to any desired order in the interaction potential at fixed density. The free energy correct to second order in the interaction strength is utilized here for calculation of other thermodynamic properties of the model. With reasonable choices of values of the interaction parameters these thermodynamic properties of the model can be brought into agreement with those of real water. 相似文献
169.
The 15°K deposition of alkaline earth metal atoms and ozone molecules at high dilution in argon yielded intense bands near 800 cm−1 and in the region, 450–650 cm−1. The bands near 800 cm−1 showed the appropriate oxygen isotopic shifts for assignment to ν3 of the ozonide ion; the use of scrambled isotopic ozones indicated that the metal cation is symmetrically bound to the ozonide anion which contains three oxygen atoms with two equivalent oxygens. For the case of Ca and Ba atoms and ozone, infrared absorptions appeared between 450–650 cm−1 which showed appropriate oxygen isotopic shifts for vibrational assignment to several metal oxide species. In the calcium experiments, bands at 635.7 and 575.5 cm−1 which showed diatomic oxygen-18 isotopic shifts were tentatively identified as (CaO)2 species; a pair of bands at 593.0 and 592.2 cm−1 were tentatively assigned to CaO2. For the barium reactions, bands at 634.7, 571.3, and 460.0 showed appropriate oxygen-18 frequency shifts for assignment to BaO, BaO2, and (BaO)2, respectively. The BaO assignment was confirmed by the N2O-nitrogen matrix reaction which yielded a nitrogen matrix counterpart for BaO at 612.4 cm−1. 相似文献
170.
Positron lifetimes have been measured as a function of temperature in 4-butyloxybenzal-4′-ethylaniline (BEA). BEA has been previously reported to have two liquidcrystalline phases (smectic and nematic) with transition temperatures as follows: solid → smectic, 40.5° C; smectic → nematic, 51.0° C; and nematic → isotropic liquid, 65.5° C. Positron life time spectra were resolved into two components, with the shorter component τ1 remaining approximately constant in all phases, and τ2 exhibiting reversible changes at all of the above transitions. In addition, an irreversible discontinuity in the τ2 lifetime was observed in the vicinity of 28° C, indicating the presence of a new phase (phase X) of BEA. The τ2 andI 2 values obtained for the various phases of BEA are: solid (1.25 nsec, 7.1%), phase X (1.97 nsec, 26.2%), smectic (2.36 nsec, 23.6%), nematic (2.72 nsec, 28.3%), and isotropic liquid (2.69 nsec, 29.8%). 相似文献