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1.
Kamila Rybczyska-Tkaczyk Teresa Korniowicz-Kowalska Konrad A. Szychowski 《Molecules (Basel, Switzerland)》2021,26(2)
The aim of this study was to evaluate the bioremoval mechanism of anthracycline antibiotics by the white-rot fungus B. adusta CCBAS 930. The activity of oxidoreductases and levels of phenolic compounds and free radicals were determined during the biotransformation of anthraquinone antibiotics: daunomycin (DNR) and doxorubicin (DOX) by B. adusta strain CCBAS 930. Moreover, phytotoxicity (Lepidium sativum L.), ecotoxicity (Vibrio fischeri), genotoxicity and cytotoxicity of anthraquinone dyes were evaluated before and after biological treatment. More than 80% and 90% of DNR and DOX were removed by biodegradation (decolorization). Initial solutions of DNR and DOX were characterized by eco-, phyto-, geno- and cytotoxicity. Despite efficient decolorization, secondary metabolites, toxic to bacteria, formed during biotransformation of anthracycline antibiotics in B. adusta CCBAS 930 cultures. DNR and DOX metabolites did not increase reactive oxygen species (ROS) production in human fibroblasts and resazurin reduction. DNR metabolites did not change caspase-3 activity. 相似文献
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3.
Dariusz Szychowski Barbara Pacewska 《Journal of Thermal Analysis and Calorimetry》2012,109(2):789-795
The purpose of this study was to determine the possibility of producing hydrophobic mesoporous mineral-carbon sorbents from aluminum hydroxide and coal-tar pitch-polymer compositions by carbonization at 600?°C in an nitrogen atmosphere. The method of homogenization was optimized using different solvents. Blends of aluminum hydroxide and coal-tar pitch with a definite composition or the products of co-precipitation of aluminum hydroxide in the coal-tar pitch-polymer medium were subjected to carbonization process. The hydrophilic?Chydrophobic properties were evaluated by adsorption of water vapors. The highest value of BET surface area about 370?m2/g, was achieved for the carbonization product obtained from co-precipitated raw components with 10?wt% coal-tar pitch-polymer compositions. 相似文献
4.
Barbara Pacewska Olga Kluk-Płoskońska D. Szychowski 《Journal of Thermal Analysis and Calorimetry》2006,86(3):751-760
Aluminium hydroxide was precipitated
during a hydrolysis of aluminium perchlorate in ammonia medium. The materials
were studied with the following methods: thermal analysis, IR spectroscopy,
X-ray diffraction, low-temperature nitrogen adsorption and adsorption–desorption
of benzene vapours.
Freshly precipitated boehmite had a high value
of SBET=211 m2 g–1
determined from nitrogen adsorption, good sorption capacity for benzene vapours,
developed mesoporous structure and hydrophobic character. After prolonged
refluxing at elevated temperature its crystallinity increased which was accompanied
by an increase of specific surface determined from nitrogen adsorption up
to 262m2g–1 ,
decrease of sorption capacity for benzene vapours and stronger hydrophobic
character. The calcinations of all boehmites at temperature up to 1200°C
resulted in formation of à-Al2O3
via transition form of γ-, δ- and θ-Al2O3.
The samples of aluminium oxides obtained after calcination at 550 and 900°C
were characterised with high values of specific surface area of 205–220
and 138–153 m2 g–1
, respectively. The SBET values calculated for the oxide samples derived from
aged hydroxides and calcined at 1200°C are higher than for the analogous
sample prepared without the ageing step. It was concluded that the process
of ageing at elevated temperature developed thermal stability of aluminium
oxides. 相似文献
5.
The purpose of this study was a preliminary evaluation of mineral-carbon sorbents preparation possibility by the method of
thermal decomposition of a mixture of aluminium oxide or hydroxide and acenaphthene and determination of their physicochemical
properties. The conditions of carbonization were established and the changes of physicochemical properties of obtained materials
as a function of organic substance content in the mineral-carbon mixture before the process of carbonization were tracked.
In these investigations the methods of thermal analysis, low-temperature nitrogen adsorption and benzene vapors adsorption
were applied. 相似文献
6.
The present work is an attempt to use the waste water stream, containing considerable amounts of aluminium chloride, for the
manufacture of mineral–carbon sorbents. The use of the wastewater has given a possibility of obtaining a suitable mineral
matrix of aluminium hydroxide for the sorbents. Atactic poly(propylene) (APP) have been used as the necessary carbon raw material.
The modification of aluminium hydroxide was attained by preliminary mixing with the organic component, followed by carbonisation.
Optimum conditions for obtaining Al(OH)3 have been determined and the effect of the amount of carbon matter on the properties of the materials obtained has been evaluated.
The studies have enabled to trace the changes in the structure and properties of the sorbents obtained.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Szychowski J Mahdavi A Hodas JJ Bagert JD Ngo JT Landgraf P Dieterich DC Schuman EM Tirrell DA 《Journal of the American Chemical Society》2010,132(51):18351-18360
The azide-alkyne cycloaddition provides a powerful tool for bio-orthogonal labeling of proteins, nucleic acids, glycans, and lipids. In some labeling experiments, e.g., in proteomic studies involving affinity purification and mass spectrometry, it is convenient to use cleavable probes that allow release of labeled biomolecules under mild conditions. Five cleavable biotin probes are described for use in labeling of proteins and other biomolecules via azide-alkyne cycloaddition. Subsequent to conjugation with metabolically labeled protein, these probes are subject to cleavage with either 50 mM Na(2)S(2)O(4), 2% HOCH(2)CH(2)SH, 10% HCO(2)H, 95% CF(3)CO(2)H, or irradiation at 365 nm. Most strikingly, a probe constructed around a dialkoxydiphenylsilane (DADPS) linker was found to be cleaved efficiently when treated with 10% HCO(2)H for 0.5 h. A model green fluorescent protein was used to demonstrate that the DADPS probe undergoes highly selective conjugation and leaves a small (143 Da) mass tag on the labeled protein after cleavage. These features make the DADPS probe especially attractive for use in biomolecular labeling and proteomic studies. 相似文献
9.
Barbara Pacewska Olga Kluk-Płoskońska Dariusz Szychowski 《Journal of Thermal Analysis and Calorimetry》2007,90(3):783-793
The paper concerns aluminium hydroxides precipitated during hydrolysis of aluminium acetate in ammonia medium, as well as
aluminium oxides obtained through their calcination at 550, 900 or 1200°C for 2 h. The following techniques were used for
analysing of obtained materials: thermal analysis, IR spectroscopy, X-ray diffraction, low-temperature nitrogen adsorption,
adsorption-desorption of benzene vapours and scanning electron microscopy.
Freshly precipitated boehmite/pseudoboehmite had high value of S
BET, very good sorption capacity for benzene vapours, developed mesoporous structure and hydrophilic character. After prolonged
refluxing at elevated temperature its crystallinity increased which was accompanied by a decrease of specific surface determined
from nitrogen adsorption, decrease of sorption capacity for benzene vapours and weakening of the hydrophilic character. Calcination
of all hydroxides at the temperature up to 1200°C resulted in the formation of α-Al2O3 via transition forms of γ-, δ-and θ-Al2O3. The samples of aluminium oxides obtained after calcination at 550 and 900°C were characterised with high values of specific
surface area and displayed quite high heat resistance, probably due to a specific morphology of starting hydroxides. The process
of ageing at elevated temperature developed thermal stability of aluminium oxides. 相似文献
10.
Barbara Pacewska Olga Kluk-Płoskońska D. Szychowski 《Journal of Thermal Analysis and Calorimetry》2007,87(2):383-393
The process of hydrolysis of
aqueous aluminium sulfate was carried on in ammonia medium at 100°C and
for different time intervals (0, 20, 39 or 59 h). The products thus obtained
were calcined at 550, 900 or 1200°C for 2 h with the aim to obtain aluminium
oxides. The materials were studied with the following methods: thermal analysis,
IR spectroscopy, X-ray diffraction, low-temperature nitrogen adsorption, adsorption–desorption
of benzene vapours and scanning electron microscopy.
Freshly precipitated
material was an amorphous basic aluminium sulfate which after prolonged refluxing
at elevated temperature in a mother liquor underwent a phase transformation
into highly crystalline NH4Al13(SO4)2(OH)6 containing tridecameric unit Al13. It was accompanied
by a decrease of specific surface area and the formation of a porous structure
less accessible for benzene molecules. Regardless of the duration of the hydrolysis
process, all products were characterised with poorly developed porous structure
and hydrophilic character. Their calcination at the temperature up to 1200°C
resulted in the formation of α-Al2O3
via transition forms of γ/η- and δ-Al2O3.
The samples of aluminium oxides obtained after calcination at 550 and 900°C
had higher values of specific surface area than starting materials due to
processes of dehydroxylation and desulfurization. The process of calcination
up to 900°C was reflected in developing of not only porous structure but
also hydrophobic character of prepared materials. The S
BET
values calculated for the oxide samples obtained from aged products of hydrolysis
at 1200°C were lower than for the analogous sample prepared without the
ageing step. It was concluded that prolonged refluxing at elevated temperature
of the products of hydrolysis of aluminium sulfate decreased thermal stability
of final aluminium oxides. 相似文献