Low Molecular Mass Gelators of Organic Liquids and the Properties of Their Gels

Solid lipid nanoparticles: Production, characterization and applications

The development of novel materials is a fundamental focal point of chemical research; and this interest is mandated by advancements in all areas of industry and technology. A good example of the synergism between scientific discovery and technological development is the electronics industry, where discoveries of new semiconducting materials resulted in the evolution from vacuum tubes to diodes and transistors, and eventually to miniature chips. The progression of this technology led to the development * To whom correspondence should be addressed. B.L.C.: (504) 2801385 (phone); (504) 280-3185 (fax); bcushing@uno.edu (e-mail). C.J.O.: (504)280-6846(phone);(504)280-3185(fax);coconnor@uno.edu (e-mail). 3893 Chem. Rev. 2004, 104, 3893−3946

http://depa.fquim.unam.mx/amyd//archivero/FidelmarLechugaSanabria_4940.pdf

Recent advances in the liquid-phase syntheses of inorganic nanoparticles.

Zinc oxide can be called a multifunctional material thanks to its unique physical and chemical properties. The first part of this paper presents the most important methods of preparation of ZnO divided into metallurgical and chemical methods. The mechanochemical process, controlled precipitation, sol-gel method, solvothermal and hydrothermal method, method using emulsion and microemulsion enviroment and other methods of obtaining zinc oxide were classified as chemical methods. In the next part of this review, the modification methods of ZnO were characterized. The modification with organic (carboxylic acid, silanes) and inroganic (metal oxides) compounds, and polymer matrices were mainly described. Finally, we present possible applications in various branches of industry: rubber, pharmaceutical, cosmetics, textile, electronic and electrotechnology, photocatalysis were introduced. This review provides useful information for specialist dealings with zinc oxide.

Zinc Oxide-From Synthesis to Application: A Review.

Challenges Eun-Kyung Lim,†,‡,§ Taekhoon Kim, Soonmyung Paik, Seungjoo Haam, Yong-Min Huh,*,† and Kwangyeol Lee* Department of Chemistry, Korea University, Seoul 136-701, Korea †Department of Radiology, Yonsei University, Seoul 120-752, Korea Severance Biomedical Research Institute, Yonsei University College of Medicine, Seoul 120-749, Korea Division of Pathology, NSABP Foundation, Pittsburgh, Pennsylvania 15212, United States Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 120-749, Korea ‡BioNanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea Electronic Materials Laboratory, Samsung Advanced Institute of Technology, Mt. 14-1, Nongseo-Ri, Giheung-Eup, Yongin-Si, Gyeonggi-Do 449-712, Korea

Nanomaterials for theranostics: recent advances and future challenges.

Structure, dynamics and transport properties of microemulsions

Pyrene absorption can be a convenient method for probing critical micellar concentration (cmc) and indexing micellar polarity

The solution properties of the surfactants dodecyl-, tetradecyl-, and hexadecyl(cetyl)trimethylammonium bromide (DTAB, TTAB, and CTAB, respectively) as well as hexadecylpyridinium chloride (CPC) in pure and mixed states (binary and ternary combinations) have been studied. The critical micelle concentration (cmc), counterion binding, aggregation number, polarity, thermodynamics of micellization, interfacial adsorption, etc., have been quantitatively estimated by surface tension, conductance, spectrophotometry, fluorescence, and calorimetric methods. The micellar compositions, activities of the components in the micelle, and their mutual interactions have been estimated from Rubingh's theory. The surfactant mixtures have been found to be nonideal, with a lower degree of counterion association compared to pure states, but possess more or less comparable micellar polarity and energetic parameters.

Micellar Properties of Cationic Surfactants in Pure and Mixed States

Gemini surfactant is the family of surfactant mole-cules possessing more than one hydrophobic tail and hydrophilic head group These surfactants usually have better surface -active properties than corres pond -ing conventional surfactants of equal chain length Geminis are used as promising surfactants in indus-tria l detergency and have shown efficiency in skin care, antibacterial property, metal-encapped porphy -ra zine and vesicle formation, construction of high-porosity materials, etc This review deals with synthesis, structure, critical micellar concentration, surface active properties and uses of geminis

Gemini surfactants: A distinct class of self-assembling molecules

Since the discovery of microemulsion s, they have attained increasing significance both in basic r esearch and in industry. Due to their unique properties, namely, ultralow interfacial tension, large interfacial area, thermodynamic stability and the ability to solubilize otherwise immiscible liquids, uses and applications of microemulsion s have been numerous. The objective of this review is to present briefly the possible applications of the novel co mpartmentallized systems of microemulsions. IT is well established that large amounts of two immi scible liquids (e.g. water and oil) can be brought into a single phase (macroscopically homogeneous but microscopically heterogeneous) by addition of an appropriate surfactant or a surfactant mi xture. This unique class of optically clear, thermodynamically stable and usually low viscous solutions, called ‘microemulsions’ 1 , have been the subject of extensive research over the last two decades primarily because of their scientific and tech nological importance. Microemulsions can have characteristic properties such as ultralow interfacial tension, large interfacial area and c apacity to solubilize both aqueous and oil-soluble compounds. For detailed information one can consult several books and review articles 2–5 . The essential distinction between normal emulsion and microemulsion is their particle size and stability; the former is ‘kinetically stable’ whereas the latter is ‘thermodynamically stable’. The stability of the m icroemulsion can be influenced by addition of salt, other additives, temperature or pressure. Normal emulsions age by co alescence of droplets and Ostwald ripening (transfer of material from small droplets to larger ones), since these processes lead to a decrease in the free e nergy of dispersion (the system is inherently thermod ynamically unstable). Thermodynamic stability of the microemulsions has been proposed by Ruckenstein and Chi 6 who considered that the free energy of formation comprises interfacial free energy, interaction e nergy between droplets and entropy of dispersion. The interaction energy between droplets has been shown to be negligible and the free energy of formation can be zero or even negative if the interfacial tension is of the

S. P. Moulik

Papers

Structure, dynamics and transport properties of microemulsions

Pyrene absorption can be a convenient method for probing critical micellar concentration (cmc) and indexing micellar polarity

Micellar Properties of Cationic Surfactants in Pure and Mixed States

Gemini surfactants: A distinct class of self-assembling molecules

Uses and applications of microemulsions