Quantitative Contactless Photothermal Monitoring Of Drying In Foodstuff Materials

The role of a quantitative method, based on contactless photothermal monitoring, in the drying process of food products was described. The influence of moisture content on the effective thermal transport properties of the materials was used in the study. The transperency consideration in the foodstuff provided direct information related to the optical and thermal parameters. The infrared detection formed the basis for analyzing the frequency dependent thermal wave signals at different drying states.741 II744746Delgadillo-Holtfort, I., (2000) Quantitative Infrared Thermograph 5, QIRT 2000, pp. 103-104. , Reims, France, edited by D. Balageas et alDelgadillo-Holtfort, I., (2001) Anal. Sci., 17, p. 507Bein, B.K., (1999) BAM-DGZfP-Berichtsband, BB 69-CD, pp. M1Xiao, P., (2001) Anal. Sci., 17, pp. s349Bolte, J., (1997) High Temp.-High Press., 29, p. 567Bein, B.K., (1986) Can. J. Phys., 64, p. 1208Bein, B.K., (1997) High Temp.-High Press., 29, p. 43

Modulated photothermal measurements applied to multi-layer superinsulation foils

Abstract -Photothermal measurements based on modulated heating in the visible spectral range and IR detection of the thermal response are used to determine the effective thermal transport properties and the shielding properties of multi-layer superinsulation foils consisting of different numbers of aluminized mylar layers and spacer layers. The measurements have been run at ambient temperature, both at ambient pressure and at reduced pressures between 1 mbar and 300 mbar

Photoacoustic and photothermal radiometry spectra of implanted Si wafers

The effects of Ar+8 and O+6 ion implantation of Si were investigated by photoacoustic (PA) and photothermal radiometry (PTR) methods. The surface of Si sample was treated with Ar+8 or O+6 ions with various doses. Amplitude and phase PA spectra of Si with and without ion-implantation were measured and analyzed in the wavelength range from 800 to 1600 nm (the energy range from 0.75 to 1.55 eV) and frequency of modulation, from 1 Hz to 100 kHz

Photothermal Investigations Of De-emulsification Of Fat/water-based Pasty Materials: Margarine

In this work a fat/water-based emulsion pasty system, margarine, is studied from the point of view of its photothermal response at temperatures of the sample near and across the temperature region at which the emulsion breaks apart. The emulsion decay has also been observed at a fixed sample temperature through the temporal behavior of its photothermal response. For these studies, two different frequency-dependent photothermal experimental techniques have been used: photo-pyroelectric detection schemes, as well as infrared radiometry. Whereas the photo-pyroelectric technique has been applied to extract integral thermal information, the photothermal infrared radiometry has been used to explore aspects concerning the sample's thermal depth profile.252587602Lissant, K.J., (1996) Emulsion and Emulsion Technology, Part I, , Marcel Dekker, New YorkSchwartzberg, H.G., Hartel, W., (1997) Phys. Chem. Foods, , Marcel Dekker, New YorkDickinson, E., Stainsby, G., (1988) Advances in Food Emulsions and Foams, , Elsevier, AmsterdamRossell, J.B., Pritchard, J.L.R., (1991) Analysis of Seeds, Fats and Fatty Foods, , Elsevier, AmsterdamVargas, H., Miranda, L.C.M., (1988) Phys. Rep., 161, p. 45Hess, P., Pelzl, J., (1988) Photoacoustic and Photothermal Phenomena, Springer Series in Optical Sciences, , A. L. Schawlow, ed. (Springer-Verlag, Berlin, Heidelberg)Pereira, J.D.R., Da Suva, E.C., Mansanares, A.M., Miranda, L.C.M., (2001) Anal. Sci., 17, p. 172Mandelis, A., Zver, M.M., (1985) J. Appl. Phys., 57, p. 9Dadarlat, D., Chirtoc, M., Nematu, C., Cândea, R.M., Bicanic, D., (1990) Phys. Stat. Sol. (A), 121, pp. K231Bolte, J., Chirtoc, M., Bein, B.K., Pelzl, J., (1996) Prog. in Nat. Sci., A6, pp. S-705Bolte, J., Gu, J.H., Bein, B.K., (1997) High Temp.-high Press, 29, p. 567Bein, B.K., Pelzl, J., Analysis of surfaces exposed to plasmas by nondestructive photoacoustic and photothermal techniques (1988) Plasma Diagnostics - Surface Analysis and Interactions, 2, pp. 211-326. , O. Auciello and D. L. Flamm, eds. (Academic Press, New York)Gibkes, J., Bicanic, D., Cozijnsen, J., Frankhuizen, R., Koehorst, R., Dóka, O., Jalink, H., Photoacoustic and photothermal phenomena (1999) AIP Conference Proceedings, 463, pp. 670-672. , F. Scudieri and M. Bertolotti, eds. (American Institute of Physics Press, Woodburry, New York

Characterization of Metal Coated Diamond Crystallites by Combined Photoacoustic Effect and Photothermal Radiometry

Photoacoustic effect and photothermal radiometry were applied to characterise the thermal properties of diamond crystallites which were coated by a Cu film, a Cr film and a Cr-Cu film. The Cu-coated diamond exhibits a considerable thermal barrier at the Cu-diamond interface which had disappeared for the crystallites with a thin bond Cr layer between diamond and Cu. The comparison of the responses of both measurement techniques reveals the non-negligible influence of the optical absorption in the visible and IR on the deduced thermal parameters

Photothermal Investigation of Cavitation Wear Protecting NiTi-Coatings

Photothermal radiometry was applied to investigate the effect of abrasion by cavitation on steel which was supplied with a wear protecting NiTi film. Phase and amplitude data from areas on the sample which where damaged differently by the cavitation effect indicate the appearance of a three layer structure with the cavitation treatment. With cavitational impact the thermal diffusion time of the first layer decreases and an interfacial layer emerges which is identified as a surface region of the steel substrate which has undergone a stress induced transformation from an austenite to a martensite structure

Photothermal and micro-thermal characterization of metal coated diamond crystallites

Photoacoustic effect and scanning near field microscopy have been applied to characterise the thermal properties of diamond crystallites which were coated by a Cu film, a Cr-film and a Cr-Cu film. The Cu-coated diamond exhibits a considerable thermal barrier at the Cu-diamond interface which had disappeared for the crystallites with a thin bond Cr-layer between diamond and Cu. The local inspection of the thermal conductivity with a thermal nano-probe operated in the 3ω-mode reveals slight local variations of the thermal conductivity of the Cr-coated crystallite

Processing Induced Change οf Thermal Transport Properties οf NiTi-Shape Memory Alloy

Photothermal radiometry was applied to investigate the influence of a rolling process on the thermal properties of NiTi foils. The thermal diffusivity and thermal effusivity of the foils were determined at room temperature from the frequency variation of the photothermal signals in thermal transmission. Measurements were conducted on unrolled, rolled and thermally annealed samples. The thermal diffusivity and thermal effusivity are found to decrease considerably on rolling which is attributed to the influence of the rolling induced lattice defects

Photothermal and micro-thermal characterization of metal coated diamond crystallites

Photoacoustic effect and scanning near field microscopy have been applied to characterise the thermal properties of diamond crystallites which were coated by a Cu film, a Cr-film and a Cr-Cu film. The Cu-coated diamond exhibits a considerable thermal barrier at the Cu-diamond interface which had disappeared for the crystallites with a thin bond Cr-layer between diamond and Cu. The local inspection of the thermal conductivity with a thermal nano-probe operated in the 3ω-mode reveals slight local variations of the thermal conductivity of the Cr-coated crystallite