Single-sided measurements

This paper deals with the control of weld depth penetration for cylinders in gold-nickel alloy and tantalum. After introducing the experimental set-up and the samples description, the study and the optimization of the testing are presented for single-sided measurements either in a pulse-echo configuration or when the pump and the probe laser beams are shifted (influence of a thermal phenomenon), and for different kind of laser impact (a line or a circular spot). First, the ultrasonic system is used to detect and to size a flat bottom hole in an aluminium plate. Indeed, when the width of the hole is reduced, its shape is nearly similar to the one of a slot. Then, the optimization is accomplished for... 

Zero sampling error Eq. (1.6) reduces to Vreprod = V repeat-Independent individual samples/measurements in the sense of Fig. 1.5. A result that is nearer to the SL(/ and an accepted risk of 5% (alpha/2 = 0.05 for the single-sided test use the alpha = 0.1 column in the t-table). 

The isotope is almost exclusively used for the investigation of chemical compounds. The resolving power of Mossbauer spectroscopy is demonstrated by the spectra from WS2 powder and single-crystal measurements as shown in Fig. 7.48 (from [222]). On the right-hand side of the picture, the angular dependence of E2 transitions for Aw = 2, 1,0 hyperfine components is indicated. 

E. C. Meister, Urs. P. Wild, P. Klein-Bolting and A. R. Holzwarth, Time-response of small side-on photomuliplier tubes in time-correlated single-photon measurements. Rev. Sci. Instrum. 59, 499-501 (1988). 

Microcantilever deflection changes as a function of adsorbate coverage when adsorption is confined to a single side of a cantilever (or when there is differential adsorption on opposite sides of the cantilever). Since we do not know the absolute value of the initial surface stress, we can only measure its variation. A relation can be derived between cantilever bending and changes in surface stress from Stoney s formula and equations that describe cantilever bending [15]. Specifically, a relation can be derived between the radius of curvature of the cantilever beam and the differential surface stress ... 

The position of ZPD (Zero Path Difference) is critical to the Fourier Transform calculation, since the algorithm assumes that the central burst in the interferogram is in fact the ZPD. However, due to the refractive index properties of the beamsplitter material, the ZPD is not at the same position for every wavelength measured. There are several ways to overcome these phase differences. The most common method is to use a correction factor, which is known as phase correction. This correction factor is calculated for every wavelength, based on a double sided interferogram, since this tends to minimize the effects of phase difference. In practice, most infrared spectrometers collect single sided interferograms, since this halves the mirror movement, and consequently the number of datapoints to be Fourier transformed. 

Wand- or dip-type probes are single-sided probes for optical transmission, absorbance, reflectance, and fluorescence measurements. Spectra-caliper probes are used for transmission measurements through solid samples such as plastic films, fibers, biological tissues, and intact plant leaves. Transmission probes are always used in pairs for optical transmission and absorption measurements. 

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