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1.
Microbiol Res ; 238: 126485, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32474293

RESUMO

Sixteenth-century Arrases from the Krakow Royal Castle constitute a Polish national cultural heritage; hence, they should be under special protection. The storage of historic objects at strict temperature and humidity conditions is fundamental for their protection against microorganisms. However, sometimes active preservation must be applied to disinfect bio-contaminated objects. In this study, 39 strains of microorganisms, both fungi and bacteria, isolated from Arrases deposited in the Wawel warehouse were isolated and then identified using molecular tools. Fungal ability to colonize and degrade silk and wool laboratory samples was studied. Selected microbial strains were compared concerning their ability to affect silk fibroin using size-exclusion chromatography (SEC). The effectiveness of low-temperature helium-generated plasma in disinfecting the model wool and silk samples inoculated with selected strains was tested. The results showed that plasma, despite its high biocidal activity in the case of paper, was not effective on porous textile materials. The alternative protection mechanism, involving active packaging in the form of textiles impregnated with silver-exchanged zeolites, could be used to separate layers of rolled tapestries in the warehouse. Nevertheless, optimal temperature and humidity conditions should be strictly maintained and controlled.


Assuntos
Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Gases em Plasma/farmacologia , Têxteis/microbiologia , Zeolitas/farmacologia , Bactérias/isolamento & purificação , DNA Bacteriano , DNA Fúngico , Desinfetantes/farmacologia , Desinfecção/métodos , Fungos/isolamento & purificação , Umidade/prevenção & controle , Viabilidade Microbiana , RNA Ribossômico 16S , Seda , Temperatura , Fibra de Lã/microbiologia
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 230: 118060, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31955123

RESUMO

The objective of our study was to develop and optimize the in situ synthesis of zeolitic thin coatings with USY (ultrastabilised form of faujasite) and MFI (Model Five) type structure on metallic structured catalysts supports using the hydrothermal method. Thus, obtained zeolitic materials were studied in terms of their prospective activity in selective catalytic reduction of nitrogen oxides (SCR of NOx) with ammonia. Optimization of the preparation method consisted of several steps including: the pretreatment of steel carrier to obtain an adhesive surface, hydrothermal synthesis of zeolites at different conditions and adjustment of the zeolite structure type (MFI vs. USY). As a result, uniform zeolitic layers were deposited on steel supports. Prepared structured supports were ion-exchanged with copper or cobalt precursors to obtain active catalysts and then characterised by various physicochemical methods with a particular reference to the in situ Fourier-Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible Diffusion Reflectance Spectroscopy (DRS-UV/VIS) and Raman spectroscopy. For CuUSY sample, slightly better catalytic properties are related to higher copper content. In the case of Co-samples, worse catalytic properties in comparison with Cu counterparts might imply from higher concentration of Brønsted acid sites, lower cobalt loading (thus concentration of Lewis acid sites) and the presence of cobalt cation significantly in oxide form (evidenced by Raman, DRS-UV/VIS spectroscopy and by in situ FT-IR sorption studies).

3.
Artigo em Inglês | MEDLINE | ID: mdl-29505939

RESUMO

Coal fly ash as a secondary aluminosiliceous raw material that is commonly used in the so-called geopolymerization process has been activated with different alkali hydroxides solutions: LiOH, NaOH and KOH. Changes in the aluminosilicate structure of the material during alkali-activation have been analyzed in detail on the basis of ATR/FT-IR spectra. These changes mainly affect both the integral intensity and FWHM of bands in the range of 1200-950cm-1, however dehydration and carbonation process can be also analyzed based on obtaining results.

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