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/DTG curve were qualitatively described [ 2 – 4 ]. The dehydration kinetics of cemetitious materials were usually characterized by the modified Arrhenius equation [ 5 ], where the cemetitious materials were considered as pure substance. However, the

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]. Therefore, we studied the kinetics and mechanisms of the spontaneous aqueous oxidative degradation by peroxydisulfate. Experimental Materials Imipramine hydrochloride (Sigma-Aldrich), opipramol dihydrochloride

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Journal of Thermal Analysis and Calorimetry
Authors: Lech Nowicki, Anna Antecka, Tomasz Bedyk, Paweł Stolarek, and Stanisław Ledakowicz

reagent forming additional amounts of synthesis gas. Apart from being used as potential fuel, the product of gasification, synthesis gas is a useful raw material for chemical industries. Char gasification kinetics depends on the gasifying agent

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. Although the drying kinetics of a product is a crucial parameter in this process, the experimental setup to measure the drying kinetics in an environment which comes close to the drying situation in a real spry dryer, is very difficult to establish. With

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. The kinetics of the Boudouard–Bell reaction/process The course of the heterophase reaction ( 1 ) is limited by many factors, including: thermodynamic parameters ( T , P , V ); the quality of the carbon carrier that is dependent upon what

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catalyst of esterification. It gives the highest reaction rate, so it is a good starting point for wide kinetic investigations. The aim of our study was an investigation of the kinetics of the syntheses of phthalic anhydride with n -heptyl, n -nonyl or n

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The real-time monitoring of the adsorption kinetic of antibody onto polyethylene terephthalate (PET) modified with gold nanoparticles (NPs) is performed into a dielectric flow microchannel. The principle is based on the microelectrode–dielectric interface excitation by a modulated voltage excitation through the dielectric layer with high frequency range. The set-up configuration using a homemade current-to-voltage converter has been developed for fast monitoring of biomolecule adsorption without direct electrical contact of microelectrodes with the microchannel flow. The change in the interfacial admittance, related to the output voltage measured through the microchip, during antibody incubation, gives information on the kinetics involved while antibodies are adsorbed at the interface. An example of adsorption on PET modified with gold NPS was taken. Experimental data were fit with the Langmuir equation and a good correlation was obtained with this latter, where the equilibrium constant, K, was found as 1.55 × 108 M−1 with a limit of detection for antibody concentration without depletion equal to 8.25 nM.

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Summary

We hypothesized that extracts from selenium (Se)-enriched Lentinula edodes mycelia would have higher anticancer and immunostimulating properties than the nonenriched extracts currently used to treat cancer. Previously, we demonstrated that submerged cultivated mycelia of L. edodes accumulated Se from the cultivation medium very efficiently, more so than yeast. The objective of this study was to investigate the kinetics of Se accumulation by L. edodes mycelial culture. The L. edodes mycelia were cultivated in medium enriched with 20 μg mL−1 Se in a 10-L jar fermenter. Each day, a 100-mL sample was taken from the fermenter and the concentration of Se in the dried mycelia, in the filtered medium, and in the wash water was determined by reversed-phase high-performance liquid chromatography (RP HPLC). We adapted a widely used fluorimetric method based on derivatization with 2,3-diaminonaphthalene for analysis of Se for RP HPLC. Se recovery was determined on the basis of the theoretical amount of Se in the cultivation medium. To detect volatile selenium compounds released from the fermenter, the concentration of Se in the ethanol and in the activated charcoal used in the washers and exhaust filters was determined. The time-course of the Se content of dry mycelial biomass and in filtered medium indicated that the most effective accumulation of Se occurred at the beginning of the trophophase (log phase of growth), between the second and fourth days of cultivation. The Se concentration in mycelia peaked on day 7 (3041 μg g−1) and decreased thereafter in proportion to the increase in the concentration of Se in the ethanol and activated charcoal from the fermenter exhaust filters.

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Summary

An effect of ultraviolet A (UVA) radiation on fluoxetine stability in solid phase with and without the presence of selected metal ions was studied using the chromatographic-densitometric method. Silica gel TLC F254 plates were used as the stationary phase and chloroform-methanol-ammonia 25% (45:4.5:0.5, v/v/v) as the mobile phase. The chromatograms were recorded densitometrically at a wavelength of λ = 260 nm.

Both the concentration and kind of an ion have an effect on the photodegradation process. Kinetic studies demonstrated that fluoxetine photodegradation is the fastest in the presence of Cu(II) ions, decreases in the presence of Fe(III) and Fe(II) ions, and is the lowest in the presence of Al(III) ions. Under conditions established without the presence of metal ions, fluoxetine maintains photostability.

The liquid chromatography-electrospray ionization/mass spectrometry (LC-ESI/MS) method was applied for the identification of decomposition products noting the presence of 3-phenyl-3-hydroxypropylamine and 4-trifluoromethylphenol.

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the presence of first-line anti-TB drugs as well as their metabolites. This study is also unique in the perspective of determining the kinetics of rifampicin ( K m and V max ) based on the metabolite formation using HLM assays and is applied in

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