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991.
It is proposed to determine damage fields on the surface of a material by using only full-field displacement measurements. A finite element approach is developed for which the unknown damage field is assumed to be piece-wise constant. Two examples are discussed in which the displacement field is either obtained by finite element analyses or measured by digital image correlation. To cite this article: D. Claire et al., C. R. Mecanique 330 (2002) 729–734. 相似文献
992.
Local measurements of the ion temperature and the spectral emissivity have been performed in the magnetized plasma of the PSI‐2 device using an optical probe. The proper operation of the probe could be demonstrated. The probe collects the light emission from a small separated plasma volume thus enabling to determine the ion temperature from Doppler‐broadening of suited spectral lines. In addition to the technical features stray light and finite Larmor radii effects ‐ limiting the spatial resolution ‐ are discussed. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
993.
A planar electrode (collector) is immersed into a weakly magnetized discharge plasma column. Positive voltage steps are applied to the collector and time resolved measurements of the plasma response are performed by emissive probes using standard boxcar technique. On the emissive probe characteristics an interesting phenomenon is observed: a few μs after the application of the voltage step to the collector (time depends on the distance between the collector and the probe), the emissive probe starts to collect additional positive current in the potential region between plasma potentials of the high and low potential plasma. This phenomenon is investigated experimentally. We give a possible qualitative explanation that additional positive current collection is due to a combination of an interaction between the collector and the probe and space charge effects of positive ions around the probe. 相似文献
994.
Abdul-Hussein SaberAL-MOUEL WangJinglong 《高校应用数学学报(英文版)》2004,19(4):435-448
The one-way multivariate repeated measurements analysis of variance (1-way MRM ANOVA) model for complete data and the sphericity test are studied. 相似文献
995.
In this work, we analyze different factors that may affect heat measurements, in a device, based on the optical beam deflection method (OBD). We demonstrate that it is possible to improve the heat limit of detection (HLOD) of the device by increasing its sensitivity using a proper cell or a proper monitoring phase. On the other hand, we prove experimentally that the gradient of the refraction index is almost vertical, so it is possible to apply a theoretical model based on one-dimensional heat propagation to predict the temporal behavior and the magnitude of the deflection beam. 相似文献
996.
The adsorption of D2O on Zr(0001) at 80 K and its subsequent reactions at higher temperatures have been studied by thermal desorption spectroscopy (TDS), work-function measurements (Δф), nuclear reaction analysis (NRA), LEED, infrared reflection spectroscopy (FTIR-RAS), Auger electron spectroscopy (AES), and static secondary ion mass spectroscopy (SSIMS). D2O adsorption on Zr(0001) at 80 K is accompanied by a Δф of −1.33 eV. The adsorbed D2O can be characterized into three layers by TDS: a chemisorbed layer (up to 0.23 ML), a second adsorbed layer, and an ice layer. The chemisorbed D2O dissociates into ODad and Dad at 80 K (possibly also into Oad) and no desorption products could be detected, implying that the reaction products dissolved into the zirconium at temperatures appropriate for each component. The ice layer and most of the second adsorbed layer desorb as molecular water during heating. The water adsorbed at 80 K did not form any long-range ordered structure, but a (2 × 2) LEED pattern that was formed by heating the sample to temperatures above 430 K is believed due to be an ordered oxygen superstructure. 相似文献
997.
Pekka Lahti 《International Journal of Theoretical Physics》2003,42(5):893-906
This talk is a survey of the question of joint measurability of coexistent observables and it is based on the monograph Operational Quantum Physics (Busch et al., Springer-Verlag, Berlin, 1997) and on the papers (Lahti et al., Journal of Mathematical Physics
39, 6364–6371, 1998; Lahti and Pulmannova, Reports on Mathematical Physics
39, 339–351, 1997; 47, 199–212, 2001). 相似文献
998.
Claude Gabrielli Patrick Hemery Pierre Letellier Michele Masure Hubert Perrot Marie-Isabelle Rahmi Mireille Turmine 《Journal of Electroanalytical Chemistry》2004,570(2):275-289
Models of an ion selective electrode involving an ionophore and mobile sites in a membrane are proposed. The first model, called the phase boundary potential model, supposed thermodynamic equilibrium; it allows the concentrations of the various species to be calculated. Then, a kinetic model, which takes into account the ionic transfer at the membrane|solution interfaces, was derived. The impedance of the membrane was calculated. It shows that a membrane with nernstian behavior shows only one capacitive loop in the impedance diagram, which is related to the conductivity and dielectric properties of the material of the membrane. Non-nernstian behavior is related to slow ionic transfer at the membrane|solution interfaces or/and transport limitation of the species in the membrane. Finite rate constants of the ionic transfer lead to a capacitive loop in the middle frequency range, whereas finite rate transport leads to a diffusional impedance in the low frequency range. 相似文献
999.
Erik Wold Johannes Bremer Ola Hunderi 《Journal of Polymer Science.Polymer Physics》1993,31(5):579-585
The polarization properties of an optical system, source–interferometer–polarizer–polymer film–detector, have been calculated. Using Mueller matrices, the intensity has been obtained as a function of polarizer angle. It is shown in some detail how polarization of the beam in both interferometer and detector optics distort the spectra. The contributions from the finite extinction ratio of the polarizer are also calculated and intensity variations caused by beam-wandering are discussed. It is shown that the commonly used procedure for correcting the spectra is wrong. Better methods for correcting the spectra are proposed. The influence of a uniaxial refractive index on the data is discussed, and experimental methods that can deal with refraction effects are presented. © 1993 John Wiley & Sons, Inc. 相似文献
1000.
A constant stress rheometer in the creep mode was used to perform free oscillatory shear measurements on soft solids. The results obtained are in good to excellent agreement compared to forced oscillatory shear measurement data. Depending on the rheologic properties of the sample and the moment of inertia of the rotating device of the measurement system, free oscillations are suited to confirm or supplemented forced oscillatory measurement results.Dedicated to Professor W. Nitsch on the occasion of his 60th birthday. 相似文献