Ronchi test with equivalent wavelength

2010 ◽  
Author(s):  
Anmi García-A. ◽  
Fermín Solomon Granados-A. ◽  
Alejandro Cornejo-R.
1978 ◽  
Vol 22 ◽  
pp. 293-302 ◽  
Author(s):  
A. P. Quinn

A critical discussion of the equivalent wavelength representation of polychromatic primary radiation as applied to the fundamental parameters method is given. This representation raises problems with appropriate selection of equivalent wavelengths and with accurate calculation of secondary fluorescence. Methods for reducing these difficulties are discussed and have been incorporated into a mini-computer program which achieves reasonable accuracy for alloy test cases.


2017 ◽  
Vol 56 (31) ◽  
pp. 8584 ◽  
Author(s):  
Dongyu Li ◽  
Zan Huang ◽  
Wenhao Mo ◽  
Yan Ling ◽  
Zhenghe Zhang ◽  
...  

2020 ◽  
Vol 59 (07) ◽  
pp. 1
Author(s):  
Dongyu Li ◽  
Zhenghe Zhang ◽  
Zan Huang ◽  
Xiaohui Wang ◽  
Zihua Zhang ◽  
...  

1971 ◽  
Vol 25 (1) ◽  
pp. 24-32 ◽  
Author(s):  
John F. Rendina ◽  
Richard E. Grojean

Electron spectroscopy for chemical analysis (ESCA) is proving to be a most valuable technique for the analytical chemist and molecular physicist. A commercially available Simpson–Kuyatt-type electron impact spectrometer for gas and vapor studies is described. High resolution electron transition spectra of gases, covering the equivalent wavelength range of x ray to infrared, are quickly and accurately obtained with this spectrometer. Ideally suited for quantitative and qualitative gas analysis, this new instrument will find extensive applications ranging from air pollution studies to molecular and atomic structural analysis.


Author(s):  
R. N. Arnold ◽  
G. B. Warburton

The flexural vibrations of the walls of thin cylinders are considered. In this type of vibration many forms of nodal pattern may exist owing to the combination of circumferential and axial nodes. Theoretical expressions are developed for the natural frequencies of cylinders with freely-supported and fixed ends and a comparison is made with the frequencies obtained experimentally. In practice, the ends of cylinders are subjected to a certain degree of fixing by end-plates, flanges, etc., and the natural frequencies thus lie between the corresponding values for freely-supported and fixed ends. To make possible the estimation of such frequencies, a method is devised in which an equivalent wavelength factor is used. This factor represents the wavelength of the freely-supported cylinder that would have the same frequency as the cylinder under consideration when vibrating in the same mode. The results of experimental investigations with various end thicknesses and flange dimensions are recorded, and from these the equivalent factors are derived. Sets of curves calculated for cylinders with freely-supported ends and covering a range of cylinder thicknesses are given. From these it is possible to obtain close approximation to the frequencies of cylinders under other end conditions by the use of an appropriate factor. An example is given of frequency calculations for a large air-receiver for which two frequencies were identified by experiment.


1976 ◽  
Vol 5 (2) ◽  
pp. 73-83 ◽  
Author(s):  
R. Tertian ◽  
R. Le Vié Sage

2021 ◽  
Author(s):  
A.Chantal Levasseur-Regourd ◽  
Edith Hadamcik ◽  
Jérémie Lasue ◽  
Julien Milli ◽  
Jean-Baptiste Renard

<p>The ESA-JAXA Comet Interceptor mission is expected to flyby a dynamically new comet (or an interstellar one) and better reveal the properties of its dust particles and nucleus surface. We therefore tentatively compare polarimetric properties of dust released by some comets, as well as present on surfaces of some small bodies.</p><p>Phase curves of the linear polarization of cometary dust particles (observed in equivalent wavelength ranges) show analogous trends. Some unique dynamically new comets or fragmenting comets (e.g. C/1995 O1 Hale-Bopp, C/1999 S4 LINEAR) may nevertheless present a higher positive branch than Halley-type or Jupiter-family comets (e.g. 1P/Halley, 67P/Churyumov-Gerasimenko). Such differences are clues to differences in the properties (sizes, morphologies, complex optical indices) of the dust particles. Dust particles, ejected by nuclei frequently plunging in the inner Solar System, might indeed partly come from quite dense a surface layer, as detected on the small lobe of comet 67P by Rosetta [1].</p><p>Although polarimetric observations of surfaces of cometary nuclei are almost impossible, observations of the rather quiescent nucleus of 1P/Encke have been obtained [2].  Similarities between polarimetric properties of 1P/Encke and atypical small bodies (e.g. Phaeton and particularly Bennu [3]), and of dust in cometary comae may be pointed out. Numerical and laboratory simulations could represent a unique tool to better understand such similarities. It may also be added that dust particles originating from comets, with emphasis on those of Jupiter-family, may survive atmospheric entry, as CP-IDPs collected in the Earth’s stratosphere, and that dust found in debris disks of stellar systems shows levels of polarization similar to those of highly-polarized comets [4].</p><p> </p><p>[1] Kofman et al., MNRAS, 497, 2616-2622, 2020, [2] Boehnhardt et al., A&A, 489, 1337-1343, 2008. [3] Cellino et al., MNRAS, 481, L49-L53, 2018. [4] Levasseur-Regourd et al., PSS, 186, 104896, 2020,</p><p> </p>


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