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1

Destabilization Of Model Wastewater In The Chemical Coagulation Process

100%

Smoczyński L., Muńska K. T., Kosobucka M., Pierożyński B., Wardzyńska R., Załęska-Chróst B.

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issue 2

269-279

EN

This paper discusses the results of laboratory analyses of the coagulation and flocculation of model wastewater. The investigated wastewater was susceptible to treatment by chemical coagulation. The effectiveness of two commercial coagulants, PAC produced at the DEMPOL-ECO Chemical Plant and PIX manufactured by KEMIPOL, was compared. A mathematical model relying on a second-degree polynomial was used to describe and analyze experimental data. In each case, the parabola minimum point was a precisely determined coagulant dose, regarded as the optimal dose. The application of a coagulant dose higher than the optimal dose reduced the effectiveness of wastewater treatment by coagulation. A detailed analysis of turbidity, suspended solids, total phosphorus and pollutant removal measured by the COD test revealed that PAC was a more effective and a more efficient coagulant than PIX. The risk of coagulant overdosing was greater with the use of PAC than PIX.

2

Synthesis and characterization of mesoporous silica: laboratory exercises for students

100%

Kosmulski M., Mączka E.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

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2016

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vol. 71

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issue 2

EN

Synthesis and characterization of SBA-15 were proposed as a laboratory course: linked series of exercises for graduate students. The standard preparation method was modified to fit a typical schedule of students’ classes, that is, 3-hours units every second week. The properties of materials obtained by different students’ groups were compared with the properties of materials obtained by means of a standard method.

3

Effect of phospholipid and (phospho)lipase modification on interfacial properties of oil/water emulsion

88%

Wiącek A. E.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

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2015

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vol. 70

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issue 1

EN

This review paper focused on the effect of typical phosphorlipid (or lecithin) and enzyme modification on electrokinetic parameters of oil/water emulsion. Physicochemical properties of the systems were investigated taking into account the effective diameter of the droplets as well as the zeta potentials using the dynamic light scattering technique. The effect of phospholipid and phospholipase modification on interfacial properties of o/w emulsion was examined as a function of temperature, pH and ionic strength (effect of Na+ or Ca2+ ions which occur in the physiological fluids). The particular role of Ca2+ ions in the dispersions with zwitterionic phospholipids (the main components of biological membrane) was confirmed.The phospholipids dipalmitoylphosphatidylcholine, DPPC or dioleoylphosphatidylcholine, DOPC having the same headgroup bound to the apolar tail composed of two saturated or unsaturated chains were used as stabilizing agents. The effective diameters do not always correlate with the zeta potentials. A possible reason for such behaviour might a mechanism different from the electrostatic stabilization. Phospholipids and their mixtures (e.g. lecithin) may undergo spontaneous aggregation in aqueous solution and selforganize into liposomes, which possess different sizes and surface affinities. These unique behaviours of phospholipid dispersion can be controlled using the investigated parameters. These findings are expected to increase in importance as phospholipid systems see more use in self-assembly applications.The other aim of the paper was the comparison of the enzyme phospholipase influence on lipid hydrolysis in the o/w emulsion environment. The work is the study which presents the twofold effect of ethanol dipoles on phosholipid hydrolysis. It is believed that the enzyme effect on the phospholipid aggregation behaviour at the oil-water interface will be helpful for understanding differentbiological phenomena.

4

Analysis of oligonucleotides by liquid chromatography with alkylamide stationary phase

88%

Buszewski B., Safaei Z., Studzińska S.

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issue 1

EN

The main aim of the present investigation was to determine retention behavior and interactions of oligonucleotides with alkylamide stationary phase. Five oligonucleotides, differing in the sequence, were tested. Changes in the composition of the mobile phase, i.e. pH (5.0−7.0) and buffer concentration (30−75 mM) were investigated in detail. In addition, the hydrophobic and electrostatic parameters were measured for the different pH’s and salt concentrations. The theoretical model of interactions between individual elements of the separation system, (e.g. solute, stationary phase, and mobile phase) based on zeta potential measurements, hydrophobic and electrostatic parameters calculation, and molecular modeling, has been considered.

5

Stability of colloidal systems - a review of the stability measurements methods

88%

Matusiak J., Grządka E.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

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2017

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vol. 72

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issue 1

EN

The stability of colloidal systems is very important in numerous already existing and new formulations. In most cases if such systems are not characterized by an appropriate stability they can not find any useful applications. The opposite process to the stabilization is the flocculation. Generally, it is undesirable. However, in a few cases the flocculation is very useful, for example in the wastewater treatment. That is why the methods used to determine stabilizing-flocculating properties of the colloidal systems are of significant importance.The paper describes types of stability and flocculation as well as the factors influencing those processes, e.g. the addition of polymers or surfactants. The methods presented in this paper are UV-VIS spectrophotometry, turbidimetry, zeta potential and density measurements.

6

Nickel Composite Coatings Reinforced Nano SiC Particles

75%

Nowak M., Mizera J., Kłyszewski A., Dobkowska A., Boczkal S., Kozik A., Koprowski P., Nowak M., Mizera J., Kłyszewski A., Dobkowska A., Boczkal S., Kozik A., Koprowski P.

Archives of Metallurgy and Materials

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2020

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vol. 65

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issue 2

7

Influence of the Electrolyte Type on the Adsorption and Electrokinetic Properties of the Ionic Polyamino Acids – Cr2O3 system

75%

Ostolska I., Wiśniewska M.

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EN

The influence of a kind of support electrolyte on the ionic polyamino acids adsorption at the chromium (III) oxide – polymer solution interface was investigated. The NaCl and CaCl2 were used as the background electrolytes. In order to determine the effect of the electrolyte, the same value of ionic strength of the test solutions were taken. It was proved that formation of intermolecular and intramolecular complexes in the presence of divalent calcium ions is responsible for essential changes in polymer adsorption. Related to the ionic character of polyamino acid two different adsorption behaviours can be observed. The increase of the ASP adsorption amount in the presence of calcium ions may be explained by formation of complexes between the dissociated carboxylic groups and Ca2+ ions. The opposite situation takes place in the case of polylysine – the application of CaCl2 results in the dramatic decrease in the polymer adsorption caused by blocking the active sites available for LYS macromolecules. In order to make a comprehensive analysis, the zeta potential and surface charge density measurements were performed taking into account the kind of the background electrolyte. The above-mentioned tests were carried out in the absence and presence of the polyamino acid at two different concentrations – 10 and 100 ppm respectively.

8

Effect of Pluronics and surfactant adsorption onto dolomite suspension zeta potential and stability

75%

Kozak A., Sadowski Z.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

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2015

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vol. 70

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issue 1

EN

Two kinds of Pluronics (PEO-PPO-PEO triblock copolymers) were used in these studies. They have mixed with anionic surfactant (sodium oleate). The adsorption isotherms of surfactant and copolymer-surfactant mixture onto dolomite have been determined.The adsorbed amount of the Pluronics increases with increasing concentration and reaches plateau. An increase of adsorbed amounts of anionic surfactant onto the mineral surfaces (dolomite) has been observed at the presence of Pluronic copolymers. The adsorption effect of triblock copolymers has been investigated on the zeta potential of dolomite at the water suspension. The interaction of anionic surfactant with copolymers causes a decrease of zeta potential to small amount due to the deformation of double electrical layer. The adsorbed non-ionic Pluronic layer partially screens the surface charge of mineral particles, and thus, reduces the zeta potential. On the other hand, the adsorption of anionic surfactant and copolymer caused a decrease of negative value of zeta potential both investigated minerals. The stability of dolomite suspension depends on the both copolymer and sodium oleate concentrations.

9

Effect of Various Organic Additives in Galvanic Bath on Properties of Ni-SiC Composite Coatings

75%

Nowak M., Mizera J., Kłyszewski A., Dobkowska A., Boczkal S., Kozik A., Koprowski P., Nowak M., Mizera J., Kłyszewski A., Dobkowska A., Boczkal S., Kozik A., Koprowski P.

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issue 4

Refine search results

Destabilization Of Model Wastewater In The Chemical Coagulation Process

Synthesis and characterization of mesoporous silica: laboratory exercises for students

Effect of phospholipid and (phospho)lipase modification on interfacial properties of oil/water emulsion

Analysis of oligonucleotides by liquid chromatography with alkylamide stationary phase

Stability of colloidal systems - a review of the stability measurements methods

Nickel Composite Coatings Reinforced Nano SiC Particles

Influence of the Electrolyte Type on the Adsorption and Electrokinetic Properties of the Ionic Polyamino Acids – Cr2O3 system

Effect of Pluronics and surfactant adsorption onto dolomite suspension zeta potential and stability

Effect of Various Organic Additives in Galvanic Bath on Properties of Ni-SiC Composite Coatings