Temat: surfactants - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Study of the influence of the binary mixtures of fluorocarbon surfactants on the surface tension of water
Autorzy:: Taraba, Anna
Szymczyk, Katarzyna
Tematy:: fluorocarbon surfactants, surface tension, binary mixtures of surfactants; Pokaż więcej
Wydawca:: Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Powiązania:: https://bibliotekanauki.pl/articles/764007.pdf Link otwiera się w nowym oknie
Opis:: Influence of the binary mixtures of fluorocarbon surfactants Zonyl FSO-100 (FSO100) and Zonyl FSN-100 (FSN100) on the surface tension of the water was studied. The effectiveness of adsorption process of the surfactant at the water-air interface was calculated from the obtained values of the surface tension of studied mixtures. Also the maximum surface area per molecule of surfactant in the interfacial area and the free energy at the water-air interface were determined. Moreover, the existence of synergetizm or antagonism effect, which reduces the surface tension of the water was examined. On the basis of the Rosen's model parameter the values of intermolecular interactions in the mixed monolayer adsorption were calculated.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Sonochemiczne metody degradacji surfaktanów.
Sonochemical methods degradation of surfactants
Autorzy:: Kowalczyk, Paulina
Opis:: Związki powierzchniowo czynne zwane również surfaktantami wykazują specyficzne właściwości wnikające z ich budowy. Substancje te, są szeroko stosowane w procesach przemysłowych oraz podczas zwykłych czynności domowych (pranie, mycie). Szerokie zastosowanie skutkuje masową emisją tych substancji do środowiska co powoduje jego skażenie (szczególnie systemów wodnych i gleby). Trwają intensywne badania nad opracowaniem metod fizycznych, chemicznych oraz biologicznych degradacji i usuwania surfaktantów ze ścieków. Praca stanowi krytyczny przegląd literatury na temat degradacji surfaktantów pod działaniem fal ultradźwiękowych. Zwięźle opisano model oddziaływania cząsteczki związku chemicznego z ultradźwiękami. Ponadto dokonano porównania mechanizmów sonochemicznej degradacji surfaktantów niejonowych i fluorowanych anionowych. Praca zawiera wyczerpującą listę surfaktantów, których sonochemiczna degradacja została opisana w literaturze wraz z warunkami jej prowadzenia. Przedyskutowano także czynniki wpływające na efektywność degradacji w ultradźwiękach. Przegląd literatury pozwolił na weryfikację możliwości zastosowania fal ultradźwiękowych w procesach oczyszczania ścieków.
Surface active agents also known as surfactants exhibit a variety of properties which are mainly determined by their structure. Those substances are widely applied in industrial processes and during everyday domestic practice (washing, cleaning). Wide application causes huge emission of surfactants which effects considerable contamination of environment (especially aqueous systems and soil). An intensive effort is taken to develop some physical, chemical or biological methods for degradation or removal of surfactants from wastewater. Thesis contains a critical review of the literature on degradation of surface active agents by means of irradiation with ultrasonic waves. Fundamentals of interaction of ultrasonic waves with chemical compounds in solution are briefly described. Moreover possible mechanism of sonochemical degradation of nonionic and fluorinated anionic surfactants were compared. Thesis also includes a comprehensive list of surfactants and conditions for their sonochemical degradation. Factors that influence the efficiency of sonochemical degradation are discussed. Finally the possibility of application of this method for wastewater treatment was verified.
Dostawca treści:: Repozytorium Uniwersytetu Jagiellońskiego

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Skocz do pozycji: 3.

Tytuł:: Zastosowanie spektometrii UV-Vis do oznaczania surfaktantów anionowych
Application of UV-Vis spectrometryfor determination of anional surfactants
Autorzy:: Hernet, Julia
Czyżewska, Magda
Kilimnik, Sebastian
Tematy:: surfaktanty
surfaktanty anionowe
spektrofotometria UV-Vis
surfactants
anionic surfactants
UV-Vis spectrophometry; Pokaż więcej
Wydawca:: Politechnika Bydgoska im. Jana i Jędrzeja Śniadeckich. Wydawnictwo PB
Powiązania:: https://bibliotekanauki.pl/articles/2055888.pdf Link otwiera się w nowym oknie
Opis:: W dzisiejszych czasach dążenia do życia bardziej ekologicznego bardzo ważnym aspektem jest kontrolowanie szkodliwego wpływu związków chemicznych na nasz ekosystem. Surfaktanty to grupa związków, która jest stosowana bardzo powszechnie w wielu gałęziach przemysłu, dziedzinach życia codziennego, a także w badaniach laboratoryjnych. Mają jednak negatywny wpływ na środowisko naturalne, dlatego nadal trwają badania nad tymi związkami. W artykule przedstawiono zagadnienia dotyczące zastosowania metod spektroskopii do oznaczania surfaktantów anionowych, wykorzystywanych zarówno w przemyśle maszynowym, samochodowym i elektronicznym, jak i przy produkcji artykułów spożywczych, kosmetycznych i włókienniczych.
Nowadays striving for a greener life is a very important aspect of controlling the harmful effects of chemical compounds on our ecosystem. Surfactants are a group of compounds that is widely used in many areas of daily life and laboratory tests. In contrast to their wide spectrum of applications, their negative impact on the environment stands, which is why research on these compounds is still ongoing. The article presents issues related to the use of spectroscopy methods for the determination of anionic surfactants, which are widely used both in the machinery, automotive and electronics industries, as well as in the production of food, cosmetics and textile.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: The use of surfactant from the Tween group in toluene biofiltration
Autorzy:: Miller, Urszula
Sówka, Izabela
Adamiak, Waldemar
Tematy:: toluene
surfactants
biofiltration
VOC; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/205431.pdf Link otwiera się w nowym oknie
Opis:: Due to the lower energy consumption and waste production compared to traditional methods, the environmental bioremediation methods based on natural processes have been gradually becoming more prevalent in environmental engineering. Biological methods are used in waste management, wastewater treatment, gas treatment or soil remediation. For the low solubility of some pollutants and lower bioavailability, the use of biological methods may be hampered. This problem might be mitigated with the use of surfactants. This paper presents the results of studies regarding the effect of dosing a selected surfactant from the Tween group (Tween 20) on the efficiency of toluene elimination from the air by biofiltration. The obtained maximum biofiltration rate was 21.2 g/m³/h and 19.8 g/m³/h for the control bed and for the bed to which the Tween 20 solution was dosed, respectively. The effect of Tween was neutral (the effectiveness of toluene removal was insignificantly comparable to the effectiveness of the control series), it did not affect the effectiveness or limited the development of the biofilter microflora.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Wpływ surfaktantów niejonowych na koalescencję kropel
Influence of non-ionic surfactants on drops coalescence
Autorzy:: Bąk, A.
Pacholewska, A.
Podgórska, W.
Tematy:: koalescencja
surfaktanty niejonowe
surfaktanty polimerowe
Tween 20
PVA
coalescence
nonionic surfactants
polymeric surfactants; Pokaż więcej
Wydawca:: Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Powiązania:: https://bibliotekanauki.pl/articles/2070592.pdf Link otwiera się w nowym oknie
Opis:: Rozważono proces koalescencji kropel toluenu w układzie z surfaktan-tem niejonowym Tween 20 i z surfaktantem polimerowym PVA. Z analizy wyników można przypuszczać, że mimo obecności środka po-I wierzchniowo czynnego powierzchnie dużych kropel pozostajączęścio-wo ruchliwe w przeciwieństwie do nieruchomych powierzchni kropel małych. Zwiększając stężenia PVA i Tweenu 20 otrzymano lepszą stabilizację dyspersji.
Coalescence of toluene droplets in the system containing non-ionic surfactant Tween 20 and polymeric surfactant PVA was considered. According to the received results it is supposed that, in spite of the presence of surface active agents, larger droplets have partially mobile interfaces while the smallest ones are immobilized. The increase of the Tween 20 and PVA concentration results in better stabilization of liquid — liquid dispersions.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: The influence of the size of the hydrophilic group on the miscibility of zwitterionic and nonionic surfactants in mixed monolayers and micelles
Autorzy:: Wydro, Paweł
Dostawca treści:: Repozytorium Uniwersytetu Jagiellońskiego

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Skocz do pozycji: 7.

Tytuł:: Współczesne surfaktanty i ich struktury micelarne tworzone w roztworach wodnych
Currently available surfactants and their micellar structures formed in aqueous solutions
Autorzy:: Jakubowska, A.
Tematy:: surfaktanty
ciecze jonowe
surfaktanty funkcjonalizowane surfaktanty polimerowe
techniki pomiarowe
struktury micelarne
surfactants
ionic liquids
functionalized surfactants
polymeric surfactants
measurement techniques
micellar structures; Pokaż więcej
Wydawca:: Polskie Towarzystwo Chemiczne
Powiązania:: https://bibliotekanauki.pl/articles/172031.pdf Link otwiera się w nowym oknie
Opis:: This article presents currently available surfactant ionic liquids as well as functionalized and polymeric surfactants. Ionic liquids (ILs) are organic salts of melting points below 100°C. They have attracted much attention due to their unique physicochemical properties such as low volatility, high thermal stability, low toxicity, high ionic conductivity, capacity to dissolve organic, inorganic and polymeric materials [1]. ILs can be used as “green” solvents in electrochemistry, extraction, chromatography, catalysis, chemical and enzymatic reactions, and synthesis of new materials [2–4]. Ionic liquids are less corrosive than classical molten salts and therefore are used as electrolytes in batteries or solar cells [5]. Like other salts, ionic liquids are formed by ions but at least one of them is an organic ion. Moreover cations and anions differ significantly in their geometrical characteristics [1]. ILs with long alkyl chains and pronounced hydrophilic and lipophilic molecular fragments have an obvious amphiphilic nature and are called the surface active ionic liquids, SAILs, because they show combined properties of ILs and surfactants [6]. Recently, there is ever-increasing interest in SAILs based on gemini surfactants (Figs 6 and 7 [21, 22]), dodecyl sulfate, DS (Fig. 8a) and aerosol-OT, AOT (Fig. 8b) anions [23–25], alkylpyridinium (Fig. 1b [11]), imidazolium (Figs 1a and 3 [13, 14, 16]), alkylpyrrolidinium [17, 18], and diisopropylethylammonium, DIPEA [19] cations. Apart from SAILs, in recent years an attention has also been paid to functionalized surfactants such as: bolaform surfactants [32], supra-long chain surfactants [35, 36], calixarene-based surfactants (Fig. 9 [33]). Surfactants of the above types of SAILs and functionalized surfactants have been synthesized and their micellar structures formed in water have been studied. For example, very interesting vesicle systems were observed in aqueous solutions of diisopropylethylamine alkyl carboxylates, [DIPEA]+[CnH2n+1COO]–, for n = 3–9 (Fig. 5 [19]) and in aqueous solutions of the surfactant mixture composed of N-dodecyl-N-methyl-pyrrolidinium and sodium dodecyl sulfate (Fig. 4 [18]). It was found that 1-hexadecyl-3-methyl-imidazolium chloride in aqueous solutions underwent the phase (micellar) transformations upon cooling (Fig. 2 [13]). An important group of polymeric surfactants attracting a great interest in literature is that of triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO), often abbreviated as [EO]a-[PO]b-[EO]a. Recently, these copolymers, also called poloxamers, have been proposed for pharmaceutical use [37–40]. These nonionic surfactants form micelles in aqueous solutions with a core containing the hydrophobic PO blocks and a shell made up of the hydrated EO blocks [41]. The subject of current studies include: the interactions between poloxamers and anionic surfactant, SDS in aqueous solutions [ 42–47], micellization of poloxamers in mixtures of water and organic solvents [48], comparison of association properties of diblock and triblock copolymers [49]. The paper also presents the experimental methods used recently to study surface activity, aggregation behaviors, and micellar structures of surfactants in water.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: Fertilizers and Pesticides Impact on Surface-Active Substances Accumulation in the Dark Gray Podzolic Soils
Autorzy:: Litvinova, Olena
Tonkha, Oksana
Havryliuk, Oleksandr
Litvinov, Dmytrо
Symochko, Lyudmyla
Dehodiuk, Stanislav
Zhyla, Roman
Tematy:: mineral fertilizer
soil
pesticides
anionic surfactants
non-ionic surfactants
crop rotation
biogenic elements
agroecosystem; Pokaż więcej
Wydawca:: Polskie Towarzystwo Inżynierii Ekologicznej
Powiązania:: https://bibliotekanauki.pl/articles/27323836.pdf Link otwiera się w nowym oknie
Opis:: The article reports on a study that examined the impact of agrochemicals on the levels of surfactants in soil. Specifically, the study found that the use of mineral fertilizers and pesticides led to an increase in the levels of anionic surfactants (ASA) in the soil. Furthermore, the simultaneous application of fertilizers and pesticides had a greater effect on ASA levels than either factor alone. The use of pesticides also led to an increase in non-ionic surfactants (NSA), while the use of fertilizers resulted in a decrease in NSA levels. The study also found that the increase in the levels of mobile forms of key nutrients in the soil was associated with the accumulation of ASA in lower layers of the soil profile.The amount of alkaline hydrolyzed nitrogen under the low protection system increased by 3.0–23.2 mg kg-1 soil, mobile phosphorus by 14.0–144.0 mg P2O5, and exchangeable potassium by 9.0–222.0 mg K2O per kg soil, compared to the control. With the complex use of fertilizers and pesticides in one block, a trend of increasing mobile forms of nutrients in the soil was observed. The distribution of ASA amount in the soil profile is descending. The clear presence of ASA was established only in the soil layer of 0–40 cm. An increase of ASA content in the soil due to the use of agrochemicals and fertilizers is observed up to a depth of 60–80 cm. Using biological elements in agriculture significantly reduces the amount of these substances in the soil profile.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:: Comparison between surface and volumetric properties of short-chain alcohols and some classical surfactants
Autorzy:: Bielawska, Magdalena
Zdziennicka, Anna
Jańczuk, Bronisław
Tematy:: alcohols, surfactants, micelles, aggregates, CMC; Pokaż więcej
Wydawca:: Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Powiązania:: https://bibliotekanauki.pl/articles/764079.pdf Link otwiera się w nowym oknie
Opis:: Measurements of the dynamic surface tension of the aqueous solutions of methanol, ethanol, propanol, CTAB and SDDS at their given concentrations were made. From the obtained results and the literature data it was concluded that the adsorption of short-chain alcohols at the water-air interface is somewhat similar to that of classical surfactants. For that reason the relationship between the Gibbs standard free energy of adsorption of short-chain alcohols and classical surfactants at that interface was established. The correlation between the chemical potential of mixing of alcohols and surfactants was also analysed. This analysis concerned the critical aggregation concentration (CAC) of alcohols and the critical micelle concentration (CMC) of surfactants. The chemical potential of surfactant mixing was calculated from the literature CMC data for the homologous series of alkyl sulfates, alkyl sulfonates, alkyl ammonium chlorides, alkyl trimethylammonium bromides, and alkyl pyridinium bromides. The influence of the hydrophobic chain length of alcohol and surfactant molecules on the Gibbs standard free energy of their adsorption at the water-air interface and their chemical potential of mixing were considered. It appeared that there is a linear dependence between these thermodynamic functions and the number of carbon atoms increased by 1 in the hydrocarbon chains of these compounds. This confirms clearly our conclusion that the behaviour of short-chain alcohols and classical surfactants at the water-air interface and in the bulk phase of aqueous solutions is similar.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:: Bioługowanie metali ciężkich z odpadów pogalwanicznych przy neutralnym pH środowiska, w obecności bakterii produkujących biosurfaktanty
Bioleaching of heavy metals from galvanic wastes at neutral pH in the presence of biosurfactant producing bacteria
Autorzy:: Karwowska, E.
Andrzejewska-Morzuch, D
Tematy:: microbial surfactants
sludge
extraction
acid; Pokaż więcej
Wydawca:: Politechnika Koszalińska. Wydawnictwo Uczelniane
Powiązania:: https://bibliotekanauki.pl/articles/1819284.pdf Link otwiera się w nowym oknie
Opis:: Precipitates and sludges from the galvanic industry are one of the sources of the environment contamination with heavy metals. Therefore, the investigations are carried out in order to developer the effective method of metals elimination from these wastes. The promising results are obtained in case of the application of microbial leaching. Up to now results concerned mainly the metals bioleaching in acidic environment. In this research work the possibility of heavy metals removal from galvanic wastes using the culture of sulphur oxidizing bacteria (pH 2-4) and a mixed culture of both sulphur oxidizing bacteria and biosurfactant producing bacteria (pH 6.5-8) was examined. It allowed to compare the process effectiveness in acidic and neutral environment. The cultures were prepared based on the activated sludge from the municipal wastewater treatment plant. The presence of sulphur oxidizing bacteria Acidithiobacillus ferrooxidans was confirmed using the PCR method. Bacillus subtilis and B. cereus strains were applied as biosurfactant producers. Three galvanic wastes, different in grain size, water content and heavy metal concentration, were bioleached. The research revealed that the metal release from galvanic wastes was more effective in presence of biosurfactant, especially in case of copper, but also for cadmium and chromium. The process effectiveness in acidic condition was comparatively lower. Zinc was the only metal that was bioleached faster in acidic environment, with similar final metal removal after 25 days of the process. The maximum values of metals elimination in the presence of biosurfactant depended on the bioleached waste type and were: 7.1-100% for copper, 3.7-50.3% for zinc, 30-50.5% for chromium, 34.1-71.9% for cadmium. The effectiveness of the nickel and lead removal was lower than 5%. The prolongation of the bioleaching period up to 40 days in case of waste C (the less susceptible to the bioleaching) resulted in elimination of 67.9% of Cu, 34.7% of Zn, 100% of Cr and 39.1% of Pb, while the effectiveness of nickel removal was still very low.
Dostawca treści:: Biblioteka Nauki

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