PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 14

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  CTAB
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available Adsorption of 4-aminopyrimidine at the R-AgLAFE/chlorate(VII) interface. Comparison of the adsorption properties of various water activity as well as different surfactants
Martyna Marlena, Pawlak Alicja, Grochowski Mariusz, Bazan-Woźniak Aleksandra, Pietrzak Robert, Nosal-Wiercińska Agnieszka
Physicochemical Problems of Mineral Processing
|
2023
|
Vol. 59, iss. 4
art. no. 170204
EN
The results of 4-aminopyrimidine (4-APM) impact studies on the double layer parameters at the R-AgLAFE/ chlorates(VII) interface in the solutions with different water activity as well as different properties of the mixed adsorption layer of 4-aminopirimidine - sodium 1-decanesulfonate (SDS) and 4- aminopyrimidine - hexadecyltrimethylammonium bromide (CTAB) at the electrode/solution interface are discussed.The differential capacity of the double layer (Cd) at the R-AgLAFE/ basic solution interface was measured using the electrochemical impedance spectroscopy. The zero charge potential (Ez) was determined using a streaming electrode, while the surface tension at the zero charge potential (Yz) was measured using the largest pressure method inside the mercury drop. It was proved that both the 4-aminopirymidine concentration and water activity have an essential effect on the doublelayer parameters on the R-AgLAFE/ chlorates(VII) interface. In the studied systems: 4-APM - SDS and 4-APM - CTAB, 4-aminopyrimidine dominance was observed.
2
Content available Study of 2–thiocytosine/ surfactant adsorption at the R-AgLAFe/chlorate(VII) interface – impact of surfactant ionic character
Martyna Marlena, Grochowski Mariusz, Urban Teresa, Nosal-Wiercińska Agnieszka
Physicochemical Problems of Mineral Processing
|
2022
|
Vol. 58, iss. 2
art. no. 144322
EN
Effect of 2 – thiocytosine on the parameters of double R-AgLAFe/ chlorate(VII) interface layer in the presence of different surfactants has been studied. There were determined the adsorption parameters such as: differential capacity of the double layer (Cd) at the R-AgLAFe/ basic electrolyte interface; potential of zero charge (Ez) and surface tension at the potential of zero charge (γz). The predominance of 2–thiocytosine in formation of adsorption equilibria of 2–thiocytosine–SDS and 2– thiocytosine–CTAB mixtures as well as the competitive adsorption between molecules 2–thiocytosine-surfactant or mixed micelles was proved. The changes pointing out to different arrangement of SDS or CTAB molecules on the electrode surface also in the presence of 2–thiocytosine were observed.
3
Content available remote Wpływ dodatku środków powierzchniowo czynnych lub polimerów na opór przepływu roztworów wodnych
Malcher Tadeusz
Przemysł Chemiczny
|
2019
|
T. 98, nr 9
1427--1429
PL
Dodatki środków powierzchniowo czynnych lub polimerów wywołują zmniejszenie oporów przepływu mediów. Przedstawiono i porównano 3 sposoby ograniczenia oporów przepływu i efekty towarzyszące temu zjawisku.
EN
Fundamentals and a review with 19 refs.
4
Content available Laccase concentration by foam fractionation of Cerrena unicolor and Pleurotus sapidus culture supernatants
Blatkiewicz M., Antecka A., Górak A., Ledakowicz S.
Chemical and Process Engineering
|
2017
|
Vol. 38, nr 3
455--464
EN
Foam fractionation process for concentration of laccases from two Basidiomycete strains under different process conditions was investigated. Culture supernatants of Cerrena unicolor and Pleurotus sapidus containing active laccase were used with and without surfactant additives. Two surfactants: cationic cetrimonium bromide (CTAB) and non-ionic Polysorbate 80 were applied in the range from 0.2 mM to 1.5 mM. The pH levels ranging from 3 to 10 were examined with particular attention to pH=4, which is close to the pI of the enzymes. Results show that the source of the enzyme is significant in terms of partitioning efficiency in a foam fractionation process. Laccase from Cerrena unicolor showed the best activity partitioning coefficients between foamate and retentate of almost 200 with yields reaching 50% for pH 7.5 and concentration of CTAB cCTAB = 0.5 mM, whereas laccase from Pleurotus sapidus showed partitioning coefficients of up to 8 with 25% yield for pH 4 and cCTAB = 0.5 mM.
5
Content available remote Photocurrent response of phloxin B-cetyltrimethylammonium bromide photogalvanic cell device
Genwa K. R., Shraddha S.
Materials Science Poland
|
2015
|
Vol. 33, No. 3
612--619
EN
Photocurrent and photovoltage generation using phloxin B dye in aqueous and micellar medium at different concentrations have been studied in a photogalvanic cell. The photopotential and photocurrent generated were 1135.0 mV and 260.0 μA, respectively. The observed solar energy conversion efficiency with CTAB surfactant was 0.64 % and maximum power of the cell was 66.72 mW. The output of the cell was sensitive to various parameters, like dye concentration, reductant concentration, pH, light intensity, electrode area and diffusion length. Current-potential characteristics studied by I-V curve of the cell and the mechanism of cell photovoltage generation have been presented in the paper.
6
Content available remote Comparative analysis of drag reduction flow efficiency through the use of surfactants and high molecular polymer additives
Matras Z., Kopiczak B.
Czasopismo Techniczne. Mechanika
|
2015
|
Y. 112, iss. 1-M
49--58
EN
A comparative analysis of drag reduction efficiency through the use of surfactants and high molecular polymer additives has been performed. Results document that for polymer micellar solutions, the stable transitional zone between the laminar flow and the turbulent flow becomes extended towards higher Reynolds number values. The existence of a third extended drag reduction zone in the turbulent range of flow is also observed. It follows that the analysed polymer-micellar solutions combine and intensify positive features of their purely polymer and micellar analogues providing a more efficient drag reduction effect in wider range of flow.
PL
Zbadano efektywność redukcji oporów przepływu za pomocą jednoczesnego wprowadzenia do rozpuszczalnika polimeru i substancji powierzchniowo czynnej. Wykazano, że dla roztworów polimerowo-micelarnych stabilna strefa przejściowa pomiędzy ruchem laminarnym i turbulentnym zostaje wydłużona w kierunku większych wartości liczb Re. Zaobserwowano wystąpienie trzeciej, rozszerzonej strefy redukcji w zakresie turbulentnym. Wynika z tego, że analizowane roztwory, łącząc i potęgując pozytywne cechy ich czysto polimerowych i micelarnych odpowiedników, zapewniają efektywniejszą redukcję oporów w szerszym przedziale przepływowym.
7
Content available remote Adsorption and co-adsorption of PEO-PPO-PEO block copolymers and surfactants and their influence on zeta potential of magnesite and dolomite
Bastrzyk A., Polowczyk I., Szelag E., Sadowski Z.
Physicochemical Problems of Mineral Processing
|
2012
|
Vol. 48, iss. 1
281-293
EN
The influence of adsorption and co-adsorption of PEO-PPO-PEO triblock copolymers (Pluronics) as well as surfactants on the zeta potential of magnesite and dolomite aqueous suspension are addressed here. Four Pluronics of various molecular weight were used in these studies. They have been mixed with cationic (CTAB) or anionic (SDS) surfactants. The adsorption isotherms of copolymers and copolymer-surfactant mixture onto magnesite and dolomite have been determined. The adsorbed amount of Pluronics increases with the increasing concentration and reaches plateau. An increase in the adsorbed amounts of both cationic and anionic surfactants onto the mineral surfaces (magnesite and dolomite) has been observed in the presence of Pluronic copolymers. A positive nature of zeta potential was observed in the presence of cationic surfactant, except magnesite without or with a low CTAB concentration. However, an attendant copolymer causes a decrease of zeta potential due to the deformation of an electrical double layer, comparing the presence of an individual cationic surfactant. 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 in the negative value of the zeta potential of both investigated minerals due to increased SDS adsorption. The viscosity measurements were also performed to determine the thickness of adsorbed layer.
8
Content available Porównanie przebiegów równolegle zachodzących flotacji jonów cynku i miedzi
Kawalec-Pietrenko B., Konopacka-Łyskawa D., Rybarczyk P.
Inżynieria i Aparatura Chemiczna
|
2011
|
Nr 5
50-51
PL
W pracy zbadano wpływ pil oraz stężenia kolektora na efektywność procesów flotacji jonowej i precypitacyjncj zastosowanych do równoległego usuwania jonów cynku Zn(II) i miedzi Cu(II) z rozcieńczonych, kwaśnych i alkalicznych roztworów wodnych. Najwyższe wartości stopnia wyfloto-wania dla obydwu metali odnotowano dla pll = 8,5 + 9,5 przy zastosowaniu SDS jako kolektora. Dla roztworów o pH> 11 zaobserwowano spadek stopnia wyflotowania ze wzrostem stężenia kolektora kationowego oraz wystąpienie czasu indukcji.
EN
An influence of pH and collector concentration on the precipitation and ion flotation efficiency used for removal of Zn(ll), Cu(II) ions from diluted, acidic and alkaline water solutions was tested. The highest values of flotation degree were noted for pH= 8.5 9.5 and for SDS used as a collector. For solutions of pH> 11, it was observed the decrease of flotation degree with the increase of cationic collector concentration and the presence of induction time.
9
Content available Koalescencja i rozpad kropel w układzie ciecz-ciecz z udziałem surfaktantów jonowych
Grabias M., Brzeszczak A., Podgórska W.
Inżynieria i Aparatura Chemiczna
|
2009
|
Nr 6
72-73
10
Determination of surface rheological parameters and their use in charcterization of dispersed systems
Pawalec M. K., Sosnowski T. R.
Inżynieria i Aparatura Chemiczna
|
2006
|
Nr 5s
108-111
EN
The paper is focused on investigations of relationships between dynamic properties of the air-liquid interface of CTAB solutions and the stability of foams produced from these solutions. The measurements were performed with the Langmuir-Wilhelmy film balance and a thermostatic glass column where foams were generated pneumatically. The results show that at the CMC region, dynamic and rheological properties of interface can govern the stability of foam layer but at higher concentrations other mechanisms may prevail.
11
Badania trwałości pian wytworzonych metodą pneumatyczną
Sosnowski T. R., Pawalec M. K., Bargieł I.
Inżynieria i Aparatura Chemiczna
|
2006
|
Nr 6s
221-222
EN
The stability of foams produced by fine bubbling in aqueous solutions of two surfactants (cationic - CTAB and non--ionic - Tween-20) was investigated for different concentrations and temperature. The data of foam persistence were discussed based on independent results of interfacial response to the surface tension disturbance. A positive correlation between the ability of generating Marangoni effects in the system and the observed stability of foam layer was found.
12
Wpływ deformacji na właściwości dynamiczne powierzchni ciecz-gaz w obecności surfaktantów
Sosnowski T., Pawelec M., Gradoń L.
Inżynieria Chemiczna i Procesowa
|
2006
|
T. 27, z. 1
93-106
PL
Rozważano efekty dynamiczne w układach wodnych zawierających surfaktanty. Mierzono odpowiedzi powierzchni podczas deformacji w układach woda-DPPC oraz woda-DPPC-CTAB. Stosując makswelowską koncepcję powierzchni lepkosprężystej, obliczono i porównano czas relaksacji dynamicznego napięcia powierzchniowego. Wykazano zaburzenie dynamiki powierzchni zawierającej fosfolipid w obecnościć CTAB i omówiono jej możliwe konsekwencje dla funkcjonowania układu surfaktantu płucnego.
EN
Measurements of the dynamic response to deformations in aqueous surface with adsorbed DPPC or DPPC/CTAB molecules were done. Based on Maxwellian concept of a visco-elastic surface, the relaxation times of the dynamic surface tension are calculated and compared, indicating the significant influence of low-molecular surfactant on phospholipid activity. Biomedical relevance of the result (in respect to the lung surfactant system) was discussed.
13
Content available remote Relaxation phenomena at the air-water interface with surfactants
Pawelec M. K., Sosnowski T. R.
International Journal of Applied Mechanics and Engineering
|
2003
|
Vol. 8, no spec.
295-300
EN
Work is focused on experimental determination of dynamic mechanical properties (i.e. compressibility and relaxation parameters) of the air-water interface during compression in the presence of DPPC monolayer. The surface dynamics was studied with the Langmuir-Wilhelmy balance in several temperatures. The influence of another surfactant (CTAB) present in the aqueous subphase on the surface with DPPC was also investigated. Discussion of the results is based on the concepts of surface rheology and physical chemistry of the interface.
14
Wpływ dodatku elektrolitu na napięcie powierzchniowe surfaktantów jonowych
Adamczyk Z., Para G., Warszyński P.
Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje
|
2000
|
Vol. 48, nr 22
67-70
PL
Określono wpływ dodatku elektrolitu (KCl) na napięcie powierzchniowe surfaktantów jonowych (CTAB, SDS). Równowagowe napięcia powierzchniowe wyznaczono metodą stalagmometryczną ważenia kropli. Względne nadwyżki powierzchniowe wyznaczano z równania Gibbsa. Wyniki doświadczalne opisano za pomocą modelu adsorpcji, którego podstawą jest założenie, że zarówno surfaktant jak i przeciwjony adsorbują się w warstwie adsorpcyjnej wraz ze zwiększeniem siły jonowej roztworu.
EN
he influence of the electrolyte (KCl) on surface tension of ionic surfactant solutions (CTAB, SDS) was examined. The equilibrium surface tension was measured by the drop weight method. The surface excess concentrations of surfactant were then determined using the Gibbs adsorption equation. The experimental results were described in terms of models of adsorption, which assume that both surfactant ions counter ions can adsorbed in Stern layer. It was found that addition of electrolyte leads to strong decrease of the surface tension. It can be explained by the reduction of the repulsive electrostatic interactions between surfactant ions in the adsorbed layer with the increasing ionic strength of the solution.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.