There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Statistics for analytical chemistry

In situ chemical oxidation of a carbamazepine solution was performed using persulfate anions simultaneously activated by heat energy (thermal, ultrasound), UV-C light, Fe2+ ions, and hydrogen peroxide. The main objective of this study was to analyze the mineralization reactions that occurred during the studied operating conditions. Solution TOC removal was nearly complete (99%) within 90 min, which prevented the accumulation of toxic intermediates. The mineralization process of carbamazepine solutions can be described using pseudo-second-order kinetics. Under acidic conditions, Fe2+ can exhibit catalytic effects on H2O2 decomposition and persulfate activation. With excess persulfate, an unproductive S2O82− decomposition reaction (with no generation of SO4 −) or a rapid reaction between excess sulfate radicals to produce sulfate anions could occur. Sulfate and hydroxyl radicals were involved in the main mineralization pathway. The influences of chloride ions on mineralization were also evaluated. The results demonstrated that this activated persulfate-based oxidation system could be used to control water pollution by emerging contaminants, such as carbamazepine.

In situ chemical oxidation of carbamazepine solutions using persulfate simultaneously activated by heat energy, UV light, Fe2+ ions, and H2O2

Chemometrics: A Textbook

Occurrence, interactive effects and ecological risk of diclofenac in environmental compartments and biota - a review

Photocatalytic degradation of hazardous Food Yellow 13 in TiO2 and ZnO aqueous and river water suspensions

The use of 1, 10-phenantroline as internal standard (IS) is proposed for spectrophotometric determination of chlorpromazine hydrochloride in pharmaceutical formulations. The spectra of both compounds: analyte and internal standard are partially overlapped, so the Savitzky-Golay alghoritm was used to obtain separated signals of analyte and IS. The best parameters to generate the second-derivative spectra were: ∠λ = 10 nm (5 experimental points) and second polynomial degree. For quantification of chlorpromazine in pharmaceuticals, the zero-crossing technique was used. The values of the second-derivative peaks were measured for chlorpromazine at 256 nm and at 236 nm for IS. Analytical characteristic for proposed method was evaluated (r2=0.9990, detection limit=3.97 ng/ml). The obtained analytical results were in good agreement with results obtained using the UV-spectrophotometric Blazek method.

The Use of Internal Standard Method for Dertvative-Spectrophotometric Determination of Chlorpromazine Hydrochloride

Removal of phthalates and other contaminants from municipal wastewater during cultivation of Wolffia arrhiza

The photodecolourization of Direct Yellow 9, a member of the group of azo dyes which are commonly used in the various branches of the industry, was investigated. The photostability of this dye was not previously examined. Photocatalytic degradation method was evaluated. Solar simulated light ( W/m2), titanium dioxide, and zinc oxide were used as irradiation source and photocatalysts, respectively. Kinetic studies were performed on a basis of a spectrophotometric method. Degradation efficiency was assessed by applying high performance liquid chromatography. Disappearance of a dye from titanium dioxide and zinc oxide surfaces after degradation was confirmed by thermogravimetry and Raman microscopy. Direct Yellow 9 was found to undergo the photodegradation with approximately two times higher efficiency when zinc oxide was applied in comparison with titanium dioxide. A simple and promising way to apply the photocatalytic removal of Direct Yellow 9 in titanium dioxide and zinc oxide suspensions was presented.

/pdf/photocatalytic-decolourization-of-direct-yellow-9-on-4h4sj4pjql.pdf

Photocatalytic Decolourization of Direct Yellow 9 on Titanium and Zinc Oxides

A novel composite with an enhanced photocatalytic activity was prepared and applied to study the removal of bezafibrate (BZF), a hypolypemic pharmaceutical, from an aqueous environment. For the enhancement of titanium dioxide photoactivity a fullerene derivative, 2-(ferrocenyl) fulleropyrrolidine (FcC60), was synthesized and applied. Obtained composite was found to show a higher catalytic activity than pristine TiO2. Therefore, high hopes are set in composites that are based on carbonaceous nanomaterials and TiO2 as a new efficient photocatalysts.

/pdf/investigation-of-novel-material-for-effective-1c3v3r85yn.pdf

Joanna Karpińska

Papers

Photocatalytic degradation of hazardous Food Yellow 13 in TiO2 and ZnO aqueous and river water suspensions

The Use of Internal Standard Method for Dertvative-Spectrophotometric Determination of Chlorpromazine Hydrochloride

Removal of phthalates and other contaminants from municipal wastewater during cultivation of Wolffia arrhiza

Photocatalytic Decolourization of Direct Yellow 9 on Titanium and Zinc Oxides

Investigation of novel material for effective photodegradation of bezafibrate in aqueous samples