The growing technique of near infrared spectroscopy is used to build fundamental knowledge of how the method might be applied for moisture determination in pulp and paper media. Filter paper was used to investigate the angle and distance dependence, otherwise obscured by the uneven surface of pulp or dry fibers. For contact measurements both filter paper and CTMP-fibers were used. The angle and distance evaluation is based on visual spectral interpretation to later incorporate preprocessing methods of the data followed by a multivariate analysis using PLS. With the knowledge built before the experimental startup, the acquired spectra are known to have many co-linearities and hence, for the purpose of determining the moisture content abundant information which might enable the reduction of data points for evaluation. The distance and angle experiments gave results indicating that the intensity of the reflected light change the information gathered and must be accounted for in calibration. Turning the measuring probe 30 degrees or more at 5 mm distance reduced the effect of high intensity specular reflection. Temperature displayed differences in the spectra, cold samples giving less response than warm samples although no clear correlation was found. Multivariate analysis of the contact measurement samples gave most accurate result after multiple signal correction preprocessing. Distance measurements on fiber rendered models with high RMSEC values and gave no reasonable base for prediction.

Heidelberg, University, Diss., 2006.

Univ., Diss.--Würzburg, 1996.

Thesis (doctoral)--Humboldt-Universiẗat, Berlin, 2003.

Techn. Hochsch., Diss., 2000--Aachen.

Zugl.: Hamburg, Techn. Univ., Diss., 2008

Charles University, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: PharmDr. Karel Palát, CSc. Student: Kristína Perďochová Title of Thesis: Homogenization of powder blends using a high-speed mixer This work focuses on using a high-speed mixer for the powder mixing process in pharmaceutical technology. Shortened experimental plan was used to study the influence of three factors (mixing speed, mixing time and weight of the mixture) in order to achieve the overall homogenity of the mixture containing acetylsalicylic acid and microcrystalline cellulose. Individual samples were compressed into tablets. The homogenity of the mixture was evaluated using near infrared spectroscopy (NIR). The standard devations of the measured spectra were observed. The best results obtained from studied mixtures were achieved by a combination of mixing 150 g of mixture, rotational speed of 900 rpm and mixing time of 30 seconds.

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No description available.

This diploma thesis focuses on the use of infrared spectrometry methods for the analysis of soil samples. The aim of this work was to compare and analyze the soil using the ATR (Attenuated Total Reflectance) and DRIFTS (Diffuse Reflectance Infrared Fourier Transform Spectroscopy) methods and to evaluate the effectiveness of these methods for soil analysis. The results showed that the ATR method is not sufficiently effective and the DRIFT method was used for soil analysis, which proved to be more suitable for the analysis of soil samples.