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Toksyczność środowiska pożarowego w budynkach a bezpieczna i skuteczna ewakuacja ludzi

Jaskółowski W.

Przegląd Budowlany

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2012

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R. 83, nr 1

40-45

PL

W artykule omówiono wybrane problemy związane z oceną toksyczności środowiska pożarowego podczas pożarów w budynkach. Na podstawie analizy literatury przedmiotu (dokumentów prawnych, norm i innych źródeł) można stwierdzić, że problem oceny toksyczności środowiska pożarowego jest problemem ciągle nierozwiązanym. Ostatnie zmiany w klasyfikacji materiałów ze względu na reakcję na ogień nie uwzględniły toksyczności.

EN

This article discusses selected problems relating to evaluation of the toxicity of a fire environment during fires in buildings. Based on analysis of the relevant literature (legal documents, standards and other sources) it can be concluded that the problem of evaluating the toxicity of the fire environment is one that remains unsolved. The most recent changes in the classification of materials based on reaction to fire did not take account of toxicity.

2

Validated stability-indicating HPLC method for analysis of gemifloxacin in tablet formulations

Sharif S, Khan I. U., Sheikh T. A, Sharif Y, Ashfaq M.

Acta Chromatographica

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2011

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Vol. 23, no. 1

95--107

EN

A stability-indicating reversed-phase high-performance liquid chromatographic method has been developed for analysis of gemifloxacin in tablet formulations. When the drug was subjected to forced degradation under acidic, basic, thermal, oxidative, and photolytic conditions, the degradation products produced were successfully separated on a 250 mm × 4.6 mm, 5-μm particle, C18 column with ammonium acetate buffer (pH 2.7; 0.05 M)-acetonitrile 70:30 (υ/υ) as mobile phase at a flow rate of 0.7 mL min-1. Diode-array detection was performed at 272 nm. The method was validated in accordance with ICH guidelines. Response was a linear function of concentration over the range 0.256–128 μg mL-1 (correlation coefficient 0.9990). The limits of detection and quantification were 10 and 30 ng mL-1, respectively. Separation of gemifloxacin from its stress-induced degradation products and excipients was adequate; resolution was >1.5 within 11 min. The purity index for the gemifloxacin peak after all types of stress was >0.999, indicating complete separation of the analyte peak from the degradation products. The method can therefore be regarded as stability-indicating. It is rapid, and suitable for purity and assay determination not only for routine quality control but also in stability studies.

3

Stability-indicating HPTLC method for analysis of torsemide in pharmaceutical preparations

Kakde R, Chaudhary N, Barsagade A, Kale D

Acta Chromatographica

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2011

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Vol. 23, no. 1

145--155

EN

A simple, precise, and accurate stability-indicating high-performance thinlayer chromatographic method for analysis of torsemide in the presence of its degradation products has been established and validated. Optimum separation among torsemide and its degradation products was achieved by use of silica gel 60F254 as stationary phase with ethyl acetate-acetonitrile-water 6.5:3.0:0.5 (v/v) as mobile phase. Densitometric quantification was performed at 297 nm. The retention factors, RF, were 0.59 ± 0.02 for the parent drug, 0.74 ± 0.02 for the degradation product from oxidation, and 0.78 ± 0.02 and 0.96 ± 0.02 for two products of acid degradation. The method was found to be linear in the range 200–800 ng per band both by area and height. The results from analysis of commercial formulations were found to be 98.49 ± 0.32 and 101.75 ± 1.54%. The method was validated for precision, accuracy, specificity, robustness, and ruggedness.

4

Identification of 1-butyl-3-methylimidazolium chloride degradation products formed in Fe(III)/H2O2 oxidation system

Siedlecka E. M., Gołębiowski M., Kumirska J., Stepnowski P.

Chemia Analityczna

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2008

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Vol. 53, No. 6

943-951

EN

The paper aims to investigate degradation mechanism of l-butyl-3-methylimidazolium chloride (bmimCI) ionic liquid in time in Fenton-like system. Reaction mixtures were analyzed for the presence of by-products applying gas chromatography coupled with mass spectrometry; identification was based on the comparison of the obtained spectra with the library spectra. Main degradation products at the first stage of reaction were imidazolones. Additionally, within one chromatographic run, 18 compounds of the same mass and similar fragmentation pattern but different retention time as imidazolones were detected. They likely represent compounds substituted with one hydroxy 1 group located in different positions of the imidazolone molecule: either in the side alkyl chain or in the ring. It was also found that the formed intermediates are rather unstable and further decompose either by ring opening or by the oxidative cleavage of the N-C bond in the N-alkyl side chain.

PL

Badano mechanizm degradacji cieczy jonowej, chlorku l -butylo-3-metyloimidazoliowego, z zastosowaniem układu pogłębionego, utleniania opartym na Fe(III)/H2O2. Wraz z postępem czasu analizowano produkty rozkładu metodąGC-MS w mieszaninie reakcyjnej, a następnie identyfikowano je na podstawie porównania otrzymanych widm z bibliotecznymi widmami mas. W pierwszym etapie reakcji głównym produktem rozkładu były imidazolony. Ponadto, analiza widm GC-MS wykazała obecność 18 związków o tej samej wartości m/z i sposobie fragmentacji, ale różnych czasach retencji. Są to prawdopodobnie imidazolony z grupą hydroksylową usytuowaną w różnych miejscach łańcucha alkilowego. Przypuszcza się, że generowane produkty rozkładu są niestabilne, dlatego ulegają dalszy m transformacjom polegającym na rozerwaniu wiązania N-C między łańcuchem alkilowym a pierścieniem lub rozerwaniu pierścienia.