Wyniki wyszukiwania - Biblioteka Nauki

1

Studies on the N-Lauroyl-N-methylglucamide Based Microemulsion with epsilon-beta Fishlike Phase Diagram

100%

Chai J. , Yang X. , Gao Y. , Zhao J. , Xu J.

Polish Journal of Chemistry

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2007

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tom Vol. 81, nr 8

1505-1509

EN

The microemulsion phase behavior of the quaternary system of N-lauroyl-N-methylglucamide (MEGA-12)/alcohol/n-octane/waterwas studied with aepsilon-beta fishlike phase diagram. The composition of the balanced interfacial layer was calculated by the - hydrophile-lipophile balanced (HLB) plane equation. The physicochemical parameters of the system were also obtained. The solubilization power was discussed.

2

Structural and Optical Characterization of ZnO Nanoparticles Synthesized by Microemulsion Route

100%

Kumar H. , Rani R.

International Letters of Chemistry, Physics and Astronomy

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2013

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tom Vol. 14

26--36

EN

ZnO nanoparticles were synthesized by microemulsion route in W/S ratio of 5 at room temperature. X-ray diffraction (XRD) pattern reveals wurtzite structure of ZnO nanoparticles. Rod shape of ZnO nanoparticles of average particle size 10.0 to 12.0 nm were observed by transmission electron microscopy. FT-IR spectra confirmed the adsorption of surfactant molecules at the surface of ZnO nanoparticles and presence of Zn-O bonding. Thermal studies were carried out by the differential scanning calorimeter (DSC) techniques. In addition, UV-Visible spectra were employed to estimate the band gap energy of ZnO nanoparticles.

3

Solubilizacja reagentów w środowisku reakcji hydroformylowania wyższych olefin w mikroemulsji

100%

Tic W. J.

Przemysł Chemiczny

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2003

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tom T. 82, nr 8-9

798-800

4

Preparation of ag/cu-doped titanium (iv) oxide nanoparticles in w/o microemulsion

100%

Zielińska-Jurek A. , Walicka M. , Tadajewska A. , Łącka I. , Gazda M. , Zaleska A.

Physicochemical Problems of Mineral Processing

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2010

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tom Vol. 45

113-126

EN

The Cu-TiO2 and Ag/Cu-TiO2 nanoparticles have been prepared using a water-in-oil microemulsion system of water/AOT/cyclohexane. The photocatalytic activity of the catalysts was estimated by measuring the decomposition rate of phenol in 0.21 mM aqueous solution under visible light irradiation. The bioactivity of Ag/Cu-doped titanium (IV) oxide nanocomposites was estimated using bacteria Escherichia coli and Staphylococcus aureus, yeast Saccharomyces cerevisiae and pathogenic fungi belonging to Candida family. The photocatalysts' characteristics by X-ray diffraction, BET surface area measurements, Scanning Electron Microscopy (SEM) energy dispersive spectroscopy (EDS) analysis showed that a sample with the highest photo- and bioactivity had anatase structure, about 190 m2/g specific surface area, absorbed light for ?>400 nm and contained 1.45 mass % of silver, 1.40 mass % of copper and 59.4 mass % of Ti.

5

Phase Behavior and Solubilization of Microemulsion System Formed by Aliphatic Polyethenoxy Ether and Sodium Dodecyl Sulfonate

100%

Chen J. F. , Gao Y. C. , Li H. L. , Chai J. L. , Yang X. D. , Qin C. K.

Polish Journal of Chemistry

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2008

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tom Vol. 82, nr 5

1067-1076

EN

The phase behavior and solubilization of the quaternary system AEO-9/AS/n- butanol /alkane/NaCl solution were investigated with delta-gamma and epsilon-beta fishlike phase diagrams. Two kinds of diagrams were plotted and compared in their shapes, HLB plane equations and solubilization power representations. Their HLB plane equations were used to calculate the composition of the hydrophile-lipophile balanced interfacial layer. It is found that the synergism between AEO-9 and AS in the inter facial layer in solubilization power exists. The influences of oil and aqueous medium on the epsilon-beta fishlike phase diagram were also discussed.

6

Selected physicochemical properties of water-fuel microemulsion as an alternative fuel for diesel engine

100%

Górska M. , Bukrejewski P. , Stobiecki J.

Archiwum Motoryzacji

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2019

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tom Vol. 84, nr 2

45--56

EN

The paper focuses on the assessment of selected physicochemical properties of microemulsion containing 5% by mass (m/m) of surface active compounds (SAC), i.e. Span20 and Crilet4 as well as 10% (m/m) of distilled water dispersed in diesel fuel (DF). In particular temperature dependent properties such as: flash point (FP) and cold filter plugging point (CFPP) as well as lubricity, friction coefficient, corrosiveness and kinematic viscosity of tested fuels were examined. It was found that the tested surfactants and water added to DF increase microemulsion FP by 13ºC. For this reason, it can be stated that tested microemulsion is safer than typical DF. On the other hand it was found that the CFPP of the tested microemulsion is also adequately higher. It means less usefulness of such fuel during winter periods. Based on the research results it can be stated that addition of tested surfactants slightly worsens the lubricity of DF. However, the same surfactants in the presence of dispersed water reduce the friction in the tribological node and improve the lubricity of the tested microemulsion. Research showed that tested microemulsion system is not corrosive as well as its kinematic viscosity meet requirements of EN590 standard. Based on all these findings, microemulsion is considered as safe and such fuel can be recommended for engine tests without the risk of its damage.

7

Preparation of Silver Nanoparticles in Reverse Micelles and Antibacterial Activity of Silver Modified-Paints

100%

Reszczyńska J. , Zieliński A. , Łącka I. , Skwarek E. , Zaleska A.

Advances in Materials Science

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2010

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tom Vol. 10, nr 4(26)

12-20

EN

Silver particles having fine or ultrafine sizes are one of the fastest growing research interests with wide applications. Here we report the preparation method of silver modified paints which revealed antimicrobial activity against gram-negative bacteria Escherichia coli, gram-positive Staphylococcus aureus, yeast Saccharomyces cerevisiae and pathogenic fungi belonging to Candida family. In this work, we choose heptane and cyclohexane, as the oil phase for preparation nanometer sized metallic particles. We have also studied the effect of different silver precursors – silver nitrate, silver citrate and different surfactants: anionic AOT, non-ionic Triton X100, Span 80 and Tween 85 for stabilization of obtained silver colloids. UV-VIS spectrum contained a strong plasmon band near 410 nm, which confirmed silver ions reduction to Ag° in microemulsion system or aqueous phases. Prepared samples contained from 500 to 2000 ppm of silver. The diameter size of silver nanoparticles was in the range from 16 nm to 82 nm and were stable for 3 months without precipitation.

8

Flotation after a direct contact of flotation reagents with carbonate particles. Part 1, Model investigations

100%

Ahmed H. A. M. , Aljuhani M. S. , Drzymala J.

Physicochemical Problems of Mineral Processing

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2013

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tom Vol. 49, iss. 2

713--723

EN

Carbonate fluorapatite (francolite), calcite and dolomite separately, as well as their model mixtures, were subjected to flotation after conditioning the particles with microemulsion consisting of 20% of Custafloat AR27 (collector, blend of fatty acid soaps and sulfates), 55% fuel oil #5 and 25% water at 70% solids density and subsequent pulp dilution with water to 25% solids. The best separation of carbonate fluorapatite from calcite and dolomite occurred at pH 8.5 and microemulsion dose between 0.9 and 1.5 kg/Mg, 1.5 min conditioning time and 2 minutes of flotation time. The obtained flotation concentrates using 1.5 kg/Mg of collector contained 84% carbonate fluorapatite (34% P2O5) with 84% recovery. The 84/84 separation efficiency in terms of grade-recovery indices points to promising results which can be obtained for real phosphate ores.

9

The Electrochemical Oxidation of Selected Antioxidants at a Glassy Carbon Electrode in Microemulsions

100%

Szymula M. , Narkiewicz-Michałek N.

Polish Journal of Chemistry

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2008

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tom Vol. 82, nr 1-2

121-129

EN

The electrochemical oxidation of three antioxidants of various hydrophilic/hydrophobic characters in microemulsions stabilized by the anionic surfactant SDS was investigated using the cyclic voltammetry method. It was found that in microemulsions the oxidation process ismore difficult than in electrolyte solutions. The oxidation potential (Epa) of hydrophobic antioxidants propyl gallate (PG) and alfa-tocopherol (alfa-T) at a glassy carbon electrode increases monotonically with the decrease of water content, whereas for the ascorbic acid (AA) the peak potential behaviour is more complicated. At first, Epa increases with the decreasing oil content up to the bicontinuous phase composition and then decreases rapidly. The currents (Ipa) for hydrophobic antioxidants are low in the whole composition range of microemulsion. For hydrophilic AA, Ipa is much higher, especially in the oil-in-water system. In the paper the changes of redox parameters of selected antioxidants are related to the micro-heterogeneity of the colloidal system and the structure of the adsorption layer formed on the electrode surface.

10

Effects of Short-chain Alcohols on the Phase Behavior, Solubilities and Solubilization Ability in Microemulsion Systems

88%

Xia Y. , Li H. L. , Chai J. L. , Yu X. Y. , Liu J. , Qin C. K. , Chen J. F.

Polish Journal of Chemistry

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2009

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tom Vol. 83, nr 2

315-324

EN

The effects of short-chain alcohols on the phase behavior, solubilities and solubilization ability in the microemulsion systems cetyltrimethyl ammonium bromide (CTAB) or cetylpyridinium bromide (CPB) or 1-hexadecyl-3-methylimidazolium bromide (C16mimBr)/1-propanol or 1-butanol or 1-pentanol/n-octane/brine were investigated with the d-g fishlike phase diagram. The phase diagram was affected greatly by alcohols, and the magnitude of the middle phase region in the fish body is in the order 1-propanol greated than greated than 1-butanol greated than1-pentanol. With the carbon chain length becoming shorter, more alcohol molecules are needed to balance the interfacial layer. Nearly all surfactants enter into the interfacial layer and little remains in aqueous or oleic phase. However, alcohols dissolve in the aqueous and oleic phases, besides they enter into the interfacial layer. The solubilization ability of the microemulsion system is mainly affected by the alcohols and the order is 1-pentanol greated than 1-butanol greated than 1-propanol.

11

Study of O/W micro- and nano-emulsions based on propylene glycol diester as a vehicle for geranic acid

88%

Jaworska M. , Sikora E. , Ogonowski J. , Konieczna M.

Acta Biochimica Polonica

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2015

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tom 62

|

nr 2

229-233

EN

Nano- and microemulsions containing as the oil phase caprylic/capric propylene glycol diesters (Crodamol PC) were investigated as potential vehicle for controlled release of geranic acid. The influence of emulsifiers and co-surfactants on stability of the emulsions was investigated. Different kind of polysorbates (ethoxylated esters of sorbitan and fatty acids) were applied as the emulsifiers. The short-chain alcohols (ethanol, 1-propanol, 1-butanol) were used as co-surfactants. The emulsions were prepared at ambient temperature (25°C), by the phase inversion composition method (PIC). The stable O/W high dispersed emulsion systems based on Crodamol PC, of mean droplets size less than 200 nm, were prepared. Microemulsions stabilized by the mixture of Polisorbat 80 and 1-butanol were characterized by the largest degree of dispersion (137 nm) and the lowest PDI value (0.094), at surfactant/co-surfactant: oil weight ratio 90:10. The stable nano-emulsion (mean droplet size of 33 nm) was obtained for surfactant: oil (S:O) weight ratio 90:10, without co-surfactant addition. This nano-emulsion was chosen to release studies. The obtained results showed that the prepared stable nano-emulsion can be used as a carrier for controlled release of geranic acid. The active substance release from the nano-emulsion and the oil solution, after 24 hours was 22%.

12

Recent Advances on Ultrasound-Modulated Two Fluid (Umtf) Atomization and its Applications

88%

Tsai S. , Tsai C.

Molecular and Quantum Acoustics

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2002

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tom Vol. 23

419-431

EN

This article presents the theoretical basis and unique capabilities of Ultrasound-Modulated Two-Fluid (UMTF) atomization that utilizes air to assist ultrasonic atomization. UMTF atomization of polymer solution s and micro-emulsion generates smaller and more uniform drops than conventional ultrasonic atomization. Its application to mass production of nanoparticles by spray pyrolysis relies on successful developement of silicon-based high frequency ultrasonic nozzles, a novel design of which is described.

13

Statistical Optimization of the Preparation of HNIW Nanoparticles via Oil in Water Microemulsions

88%

Bayat Y. , Zarandi M. , Khadiv-Parsi P. , Salimi Beni A.

Central European Journal of Energetic Materials

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2015

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tom Vol. 12, no. 3

459--472

EN

HNIW (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) is a family member of high-energy density cage nitramines which have so many versatile applications. In this paper, HNIW nanoparticles were prepared by the oil in water microemulsion route. The effects of various experimental parameters on this reaction were investigated using the Taguchi method. The effects of different variables: organic phase, water/organic phase (W1/W2), organic phase/ propanol (W3/W4) and HNIW weight percent, on the particle size of the HNIW were investigated at three distinct levels. Optimal conditions for obtaining HNIW nanoparticles were determined. Performing the process under the optimal conditions proposed by the Taguchi method leads to the production of HNIW nanoparticles with an average size of about 80 nm. The HNIW nanoparticles were characterized using Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Differential Thermal Analysis (DTA) and X-Ray Diffraction (XRD).

14

Preparation and characterization of SiO2 microspheres doped with CoFe2O4 nanocrystals

88%

Tyrpekl V. , Poltierová-Vejpravová J. , Plocek J. , Nižňanský D.

Materials Science Poland

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2010

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tom Vol. 28, No. 1

129--137

EN

Main goal of the reported work was to fabricate silica microspheres doped with magnetic nanocrystals. Cobalt ferrite nanocrystals were fabricated separately via surfactant-assisted coprecipitation. The sol-gel method in microemulsion was subsequently used for encapsulating of the magnetic nanonanocrystals into the silica microspheres. Final products were characterized by various techniques and magnetic measurements. The obtained silica microspeheres doped with CoFe2O4 were of average diameter 11 žm.

15

Water - fuel microemulsions influence on fuel consumption and exhaust gas emissions

88%

Cienciała M. , Haller P. , Jankowski A. , Kardasz P.

Journal of KONES

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2013

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tom Vol. 20, No. 3

111--116

EN

Combustion in a diesel engine is a complex physicochemical process, changing the time at which the events take place simultaneously heat and mass transfer and chemical reactions. The development of internal combustion engines goes towards meeting the increasingly stringent requirements for toxic exhaust emissions, reducing fuel consumption and therefore reduce carbon emissions and protect the Earth's natural resources. The problem to solve in modern combustion engines is the emission of NOx. One way to reduce the emission of toxic NOx combustion engine power is water-hydrocarbon emulsions [1]. Research combustion engines water-hydrocarbon emulsions has been its tradition. So far, attempts were carried out using an emulsion obtained by a chemical. Emulsions of oil and water can be obtained by adding various detergents to prevent delamination of the oil and water. In this article, we consider the possibility of applying a mixture of water and oil as an alternative fuel used to power internal combustion engines used in heavy road transport. This work is preliminary work, also having to check whether this is the future direction of the work. The measurements of emissions of exhaust gases and fuel consumption. After analysing the test results confirmed that the improvement of the economic and environmental performance of modern diesel engines, it can be achieved by supplying synthetic diesel or gas oil water emulsions. It was found that the use of emulsion leads to a reduction of fuel consumption and NOx emissions.

16

Ekstrakcja białek przy użyciu odwróconych miceli

75%

Matla M. , Smętek A. , Pyć R.

Biotechnology and Food Science

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2011

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tom Vol. 75, nr 1

97-108

PL

Odwrócone micele, czyli mikroemulsje typu woda w oleju są trójskładnikowymi systemami, które składają się z wody, cząsteczek surfaktantu i rozpuszczalnika organicznego. Mogą one być wykorzystywane do ekstrakcji w układzie ciecz-ciecz celem oczyszczania i wydobywania białek i innych cząsteczek. Odwrócone micele są atrakcyjnymi narzędziami w biotechnologii, ponieważ ekstrakcja w tych systemach jest tania, wydajna i łatwo jest w niej powiększać skalę. Wydajność ekstrakcji białek i ich rozpuszczanie w odwróconych micelach zależy od wielu czynników, takich jak pH, siła jonowa czy rodzaj i stężenie surfaktantu. W poniższym artykule przedstawiono proces ekstrakcji białek w odwróconych micelach i ich potencjalne zastosowania. Określono także i omówiono czynniki, które wywierają wpływ na ekstrakcję w układzie ciecz-ciecz.

EN

Reversed micelles, or water-in-oil microemulsions are three-component systems, that consist water, surfactant molecules and organic solvent. They can be used for liquid-liquid extraction to purificate and recovery proteins and other molecules. Reversed micelles are attractive tools for biotechnology because extraction in this systems is cheap, efficient and easy to scale up. Efficiency of protein extraction and solubilization in reversed micelles depends on many factors like pH, ionic strength, surfactant type and concentration. The present review describes the process of protein extraction in reversed micellar systems and shows potential applications of it. It also specify and describe factors that affect liquid-liquid extraction.

17

Studies on the Interfacial Composition, Thermodynamic Properties and Structural Parameters of W/O Microemulsions Containing Surfactant-like Ionic Liquid

75%

Li Y. , Chai J. L. , Xue X. N. , Zhang Z. M.

Polish Journal of Chemistry

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2009

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tom Vol. 83, nr 10

1809-1820

EN

The interfacial composition, ther mo dy namic prop er ties and struc ture pa ram e ters of the microemulsion systems con tain ing surfactant-like ionic liquid have been investigated with the dilution method of the W/O microemulsions. The interfacial parameters of Xa i , thermodynamic properties K, –Delta Go i o rghtwards arrow and structure parameters Re, Rw, Nd, Ns, Na have been calculated and discussed for microemulsion systems surfactant-like ionic liquid C12mimBr (C14mimBr, C16mimBr) / alcohol / alkane / water. The effects of water content, alcohols, alkanes, salinity and temperature on above parameters were dis cussed. The results show that with the in crease insalinity and the carbon chain length of both surfactant and alcohol, or with the decrease in the carbon chain length of the alkanes, the molar fraction of the alcohol at the interfacial layer (Xa i ) decreases, the formation of the micro - emulsion is more spontaneous in thermodynamics, and the droplets of the W/O microemulsion were enlarged. The size of the microemulsion droplets is sensitive to the water content, and increases significantly with increasing water content.

18

Studies on biocompatible nanocapsules formed in microemulsion templated processes

75%

Zielińska K. , Wilk K. A. , Seweryn E. , Pietkiewicz J.

Materials Science Poland

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2008

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tom Vol. 26, No. 2

443--450

EN

Phase diagrams of the pseudoternary system: N-alkyl-N-methylgluconamines/isobutanol/isooctane /water have been determined. Size and morphology of organic/water microemulsion droplets (optically isotropic, low viscosity one-phase systems) have been characterized by dynamic light scattering (DLS) to select systems suitable to prepare by interfacial polymerization poly(ethyl-2-cyanoacrylate) nanocapsules, the latter analyzed by scanning electron microscopy (SEM). The diameter of the nanocapsules (ranging from 300 to 1550 nm) was found to be dependent on the the monomer mass used in the polymerization process. Investigation of those nanoparticles as a cyanine IR-768 carrier, for enhancing the photosensitizer selective delivery to tumor cells, has been performed. Incubation of MCF-7 Dox cells with cyanine dye IR-768 (Indoc5), free or encapsulated in nanoparticles, allowed the cellular accumulation of the photosensitizer. Our preliminary experiments indicate that higher doses of encapsulated cyanine improved the cytotoxic effect.

19

Zastosowanie mikroemulsji jako składnika poprawiającego sprawność płynów szczelinujących i odbiór cieczy po wykonanym zabiegu

75%

Czupski M.

Nafta-Gaz

|

2012

|

tom R. 68, nr 3

171-179

PL

Bardzo ważnym czynnikiem mającym wpływ na powodzenie zabiegu hydraulicznego szczelinowania skał zbiornikowych jest sprawność płynu, która z kolei zależy od jego filtracji do złoża. Kluczowe znaczenie ma także oczyszczenie strefy dookoła wytworzonej szczeliny, jak również samej warstwy podsadzki. W tym celu do płynów szczelinujących dodawane są środki powierzchniowo czynne, których zadaniem jest redukcja napięcia powierzchniowego i kąta zwilżania oraz kontrola filtracji. Od około dekady z powodzeniem stosowane są również mikroemulsje, które stanowią mieszaninę środka powierzchniowo czynnego, rozpuszczalnika/ropy/współrozpuszczalnika i wody. Dlatego w niniejszym artykule zaprezentowano badania, które miały na celu sprawdzenie wpływu, jaki na właściwości cieczy szczelinujących będzie miało zastosowanie w ich składzie dostępnych na rynku mikroemulsji, w porównaniu do konwencjonalnego środka powierzchniowo czynnego.

EN

Fracturing fluid efficiency is a very important factor which has a crucial impact on the success of hydraulic fracturing treatment. This fluid efficiency depends on the leakoff. Then, cleanup of the area around the fractured proppant pack and propped fracture is also very important. Therefore surfactants are used in hydraulic fracturing fluids to reduce surface tension, contact angle and leakoff control. For about a decade microemulsions have also been used successfully. They are defined as a mixture of surfactant, solvent/oil/co-solvent and water. So this paper describes laboratory studies, which illustrate how the application of the microemulsions affects the fracturing fluid properties, in comparison to a conventional surfactant.

20

Rheological investigations of pharmaceutical emulsions prepared with modified lecithin

75%

Rosa M. , Kwiecień M. , Tal-Figiel B.

Czasopismo Techniczne. Chemia

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2013

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tom R. 110, z. 1-Ch

69--77

EN

In this paper the results of rheological investigations of pharmaceutical microemulsions prepared using modern lecithine derived emulsifiers has been prevented out. High stability of obtained systems and wide possibilities of controlling rheological parameters were found.

PL

W artykule przedstawiono wyniki badań reologicznych mikroemulsji farmaceutycznych, sporządzonych z wykorzystaniem nowoczesnych emulgatorów na bazie lecytyny. Stwierdzono wysoką stabilność tych układów oraz duże możliwości regulowania właściwości reologicznych.