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[en] The properties of nanoemulsions and various methods for their preparation including the high-energy and low-energy emulsification methods and the combined methods are reviewed. Among the high-energy methods, the emphasis is placed on high-energy stirring, ultrasonic emulsification, high-pressure homogenization including microfluidics and membrane emulsification. Among the low-energy emulsification methods, the attention is focused on the phase inversion temperature method, the emulsion inversion point method and the spontaneous emulsification. Using a combined method, which includes the high-energy and low-energy emulsification, it is possible to prepare reverse nanoemulsions in highly viscous systems. Main advantages and limitations of different methods of nanoemulsion preparation are discussed and the potential fields of nanoemulsion applications are considered. The bibliography includes 255 references.
[en] Surfactants are widely used for various purposes in industry, but for many years were mainly chemically synthesized. It has only been in the past few decades that biological surface-active compounds (biosurfactants) have been described. Biosurfactants are gaining prominence and have already taken over for a number of important industrial uses, due to their advantages of biodegradability, production on renewable resources and functionality under extreme conditions; particularly those pertaining during tertiary crude-oil recovery. Conflicting reports exist concerning their efficacy and the economics of both their production and application. The limited successes and applications for biosurfactants production, recovery, use in oil pollution control, oil storage tank clean-up and enhanced oil-recovery are reviewed from the technical point of view. (author)
[en] 'Full text:' The authors have discovered errors in the author listing and addresses of the published article. This has now been corrected as shown above. We apologize for any inconvenience these errors may have caused.
[en] Indigenous crude oils could be degraded and emulsified upto varying degree by locally isolated bacteria. Degradation and emulsification was found to be dependent upon the chemical composition of the crude oils. Tando Alum and Khashkheli crude oils were emulsified in 27 and 33 days of incubation respectively. While Joyamair crude oil and not emulsify even mainly due to high viscosity of this oil. Using adsorption chromatographic technique, oil from control (uninoculated) and bio degraded flasks was fractioned into the deasphaltened oil containing saturate, aromatic, NSO (nitrogen, sulphur, oxygen) containing hydrocarbons) and soluble asphaltenes. Saturate fractions from control and degraded oil were further analysed by gas liquid chromatography. From these analyses, it was observed that saturate fraction was preferentially utilized and the crude oils having greater contents of saturate fraction were better emulsified than those low in this fraction. Utilization of various fractions of crude oils was in the order saturate> aromatic> NSO. (author)
[en] We studied on preparation of nanoparticles modified surface using biodegradable polymer, poly(DL-lactide-co-glycolide) (PLGA). Two kinds of PLGA nanoparticles were prepared by a Spontaneous Emulsification Solvent Diffusion (SESD) method using CetylTrimethylAmmonium Chloride (CTAC) and TetradecylTrimethylAmmonium Bromide (TTAB) as a cationic surfactant and polyethylene glycol-block-polypropylene glycol copolymer (Lutrol F68) as a nonionic surfactant. Model protein was coated on the surface of nanoparticles by the ionic complexation. The model protein was that influenza vaccine (H3N2, H1N1, B strain) labeled with NHS-fluorescein. The sizes of cationic nanoparticles were 140-160 nm and the surface charges were 50-60 mV. The sizes of nonionic nanoparticles were 80-90 nm and the surface charge was -10 mV. After coating vaccine on the surface of nanoparticles, the sizes of cationic nanoparticles were increased to 380-400 nm and the size of nonionic nanoparticles was not increased. The amount of coated vaccine on the cationic nanoparticles was 22.73 μg/mg
[en] A method of upgrading the properties of bio-oil with bio-diesel has been taken in this article. Firstly, the unpopular pyrolytic lignin fraction is extracted from bio-oil using ether, the rest ether-soluble fraction of bio-oil, named ES is mixed with bio-diesel according to emulsification. The optimal conditions for obtaining a stable ES/bio-diesel mixture are with octanol surfactant dosage of 3% by volume; initial ES to bio-diesel ratio of 4:6 by volume; stirring intensity of 1200 rpm; mixing time of 15 min and mixing temperature at 30oC. Additionally, selected fuel properties such as viscosity, water content and acid number are measured for characterising the ES/bio-diesel mixture. Thermogravimetric analysis (TGA) has been used to further evaluate the thermal properties. Data from the TGA and Fourier transform infrared spectroscopy (FTIR) analyses confirm the presence or absence of certain group of chemical compounds in the mixture. Proton and carbon atoms assignments are further confirmed by 1H NMR (nuclear magnetic resonance) and 13C NMR analysis, respectively. (author)
[en] We present a single-substrate display device characterized by nano-sized liquid crystal droplets that can be applied to various optical devices. The nano-emulsified liquid crystal droplets can be encapsulated, and their size can be controlled through the number of dispersions. We demonstrate the electro-optical characteristics of a single-substrate display device with capsulated liquid crystal droplets with a diameter of approximately 200–300 nm fabricated using the nano-emulsification process for display applications. The contrast ratio, threshold voltage, and response time of a singlesubstrate display device using nano-sized liquid crystal droplets are approximately 25:1, 12 V, and 46.26 ms, respectively.
[en] Microfluidic emulsification yields droplets with extremely narrow size distribution, multiple emulsions with a precisely controlled number of inner droplets, and higher order emulsions ranging from double to quintuple emulsions. However, production rates are inherently small and scale-up can be achieved by massive parallelization only. Can the control that microfluidic emulsification offers for drop production nevertheless be used for the production of materials? What will it take to develop it into an industrial process? Many obstacles need to be addressed ranging from technological, and commercial issues to a fragmented and confusing conference and supplier landscape. This contribution gives a large chemical industry's perspective on formulating materials in massively parallelized microfluidic processes. (paper)