Ferrohydrogels are synthesized by incorporation of magnetic CoFe2O4 nanoparticles into a polyacylamide hydrogel network during the polymerization process by utilizing different cross-linking units. Conventional cross-linked ferrohydrogels, using a molecular cross-linker, are compared to those obtained by our new approach where the magnetic particles, surface-functionalized with methacylic groups, serve as sole, multifunctional cross-linkers. Both experimental series are analyzed with regard to their swelling behavior. The novel composite network is examined with respect to the cross-linkage, the network homogeneity, and the network architecture by various experimental techniques.

Monodisperse gold nanoparticles (AuNPs) were obtained by hydrolytic decomposition of a new molecular precursor, tetramethylammonium bis(trifluoromethyl)aurate(I), [NMe4][Au(CF3)2], which has been characterised by spectroscopic and single‐crystal X‐ray diffraction analyses. On account of the simple and high‐yield synthesis, the title compound represents a versatile synthon and an alternative to the commonly used chloroauric acid (HAuCl4).

An efficient synthesis of highly crystalline SnO(2) QDs with a narrow size distribution (4.27 +/- 0.67 nm) was achieved by microwave-assisted decomposition of Sn(OtBu)(4) in ionic liquid. Printed structures fabricated from SnO(2) QDs showed typical semiconducting I-V behaviors, and gas sensing properties.

The incorporation of surface-functionalized spindle-like hematite nanoparticles as particulate cross-linkers in poly(acrylamide) hydrogel matrices delivers ferrogels with a covalent type of particle−matrix interaction. By systematic investigation of the stability and the internal architecture of the resulting gels, the regime of resilient gels is identified. The swelling properties and the rheological behavior are in accordance with a network structure based on particle nodes interlinked by long polymer segments and a significant fraction of loops.

The concentration vs composition diagram of aggregate formation of the dodecyltrimethylammonium bromide (DTAB) and didodecyldimethylammonium bromide (DDAB) mixture in aqueous solution at rather dilute region was constructed by analyzing the surface tension, turbidity, and electrical conductivity data and inspected by cryo-TEM images and dynamic light scattering data. Although the aqueous solution of DTAB forms only micelles, the transition from monomer to small aggregates and then to vesicle was found at 0.1 < X2

In this paper, we present a new freeze fracture method for specimen preparation for transmission electron microscopy frozen samples. We call it freeze fracture direct imaging (FFDI) because it is a hybrid of conventional freeze fracture electron microscopy (FFEM) and cryo-transmission electron microscopy (cryo-TEM), combining elements of the fracture technique with direct imaging. Like in FFEM, the sandwich method is used to prepare the sample in a protected fashion. However, after the sample is vitrified and fractured, it is not shadowed but directly imaged. The new technique avoids some experimental artifacts produced by the blotting procedure in conventional cryo-TEM. It relies, though, on occasional fractures transparent to the electrons. The advantageous features are demonstrated by a comparison between conventional cryo-TEM and FFDI micrographs of vesicular solutions. The second outstanding advantage over conventional cryo-TEM is the fact that it is now possible for the very first time to directly image oil-rich mixtures films which normally would dissolve in the cryo-medium ethane. Micrographs of pure oil and of oil-rich microemulsions clearly prove the reliability of the FFDI technique as well as its enormous potential.

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Results of dynamic light scattering experiments are reported which demonstrate that the mutual diffusion coefficient of 2-butoxyethanol/water mixtures of noncritical composition exhibits a characteristic temperature and composition dependence: The diffusion coefficients of the two phases of noncritical composition coexisting along the liquid/liquid coexistence curve decrease by an order of magnitude in the temperature range (Tp−Tc)&lt;10 K approaching the lower critical point (Tp, temperature of phase separation; Tc, critical temperature). In the homogeneous 1-fluid phase region of the phase diagram, the D vs (T−Tp) curves of mixtures of noncritical composition are shifted to smaller values of D with decreasing values of ‖y−yc‖ (y, mass fraction of 2-butoxyethanol; yc, critical mass fraction). These findings are discussed on the basis of the model of regular mixtures.