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Coronal structures of the micelles spontaneously formed in water by poly(ethylene oxide)-b-polybutadiene (PEO-PB) were investigated using small-angle neutron scattering (SANS). The results are consistent with the view that the PEO segments, despite favorable interactions with water molecules, are significantly accumulated near the hydrophobic interface, possibly due to the effect of the strong incompatibility of PB and water.

More than 30 billion pounds of organic and halogenated solvents are used worldwide each year as process aids, cleaning agents, and dispersants (1), and solvent-intensive industries are considering alternatives that [...], Interfacially active block copolymer amphiphiles have been synthesized and their self-assembly into micelles in supercritical carbon dioxide (C[O.sub.2]) has been demonstrated with small-angle neutron scattering (SANS). These materials establish the design criteria for molecularly engineered surfactants that can stabilize and disperse otherwise insoluble matter into a C[O.sub.2] continuous phase. Polystyrene-b-poly(1,1-dihydroperfluorooctyl acrylate) copolymers self-assembled into polydisperse core-shell-type micelles as a result of the disparate solubility characteristics of the different block segments in C[O.sub.2]. These nonionic surfactants for C[O.sub.2] were shown by SANS to be capable of emulsifying up to 20 percent by weight of a C[O.sub.2]-insoluble hydrocarbon into C[O.sub.2]. This result demonstrates the efficacy of surfactant-modified C[O.sub.2] in reducing the large volumes of organic and halogenated solvent waste streams released into our environment by solvent-intensive manufacturing and process industries.

Vortex lattice scattering in YBa2Cu3O7 was investigated using neutron diffraction measurements. The results showed that the application of a field along the c axis produces a square pattern. However, the application of a similar field some distance from the c axis produced a triangular pattern. The square pattern featured a vortex lattice with long-range orientational order but only short-range positional order.

The magnetic characteristics of the Laves phase compounds Ce(Fe1-xAlx)2 were investigated using small-angle neutron scattering. The results showed that pure samples featured a ferromagnetic transition near a Curie temperature of 225 K. On the other hand, disordered samples exhibited ferromagnetic-like states over a relatively narrow temperature range and an additional low-temperature phase.

Focuses on the characterization of fullerenes and fullerene derivatives by small-angle neutron scattering (SANS) and transmission measurements. High scattering length density of deuterated solvents; Highlight of the different features of the structure; Assessment of the number of cyclohexane molecules attached to the fullerene 'sphere.'

The Horiuti-Polanyi mechanism for ethylene hydrogenation over Pd(111) is examined suing first-principle density functional quantum chemical calculations. Cluster and periodic slab DFT-GGA calculations are carried out to determine the modes and energies of chemisorptions for a sequence of proposed intermediates, along with overall reaction energies and activation barriers for each of the speculated elementary steps.

A rapid and accurate method is developed to characterize equilibrium aqueous solution surface tension variations due to adsorption of volatile hydrophobic organic compounds (VHOs) at the vapor/water interface. The procedure involves contacting an initially solute-free pendant water drop with an advecting air stream containing water vapor and slowly increasing VHOC vapor concentration at atmospheric pressure.

The atomic structures of nanorystalline powders of ceria, CEO2 and cera-zirconia solid solution are examined by the pulsed neutron diffraction technique. The conclusion suggests that oxygen defects are the source of OSC in ceria-based catalyst supports and the preservation of oxygen defects is critical for the stability of OSC against thermal aging.

Layered double hydroxides (LDH) materials in the lamellar or mixed-oxide form, which can be obtained by controlled calcination, have shown very attractive properties as catalysts in a wide variety of base-catalyzed reactions. They have also been largely used as supports or precursors of supported metal catalysts exhibiting a basic character and a particular metal-support interaction.

Au nanoparticles prepared by thiocyanate reduction method are too small to exhibit the characteristic surface plasmon band. The phtoinduced morphological changes in gold/rhodamine 6G nanoassemblies are elucidated using picosecond laser flash photolysis.

The formation of a water-in-carbon dioxide microemulsions with a cationic perfluropolyether trimethylammonium acetate surfactant is described. Water and carbon dioxide may be combined to form microemulsions as environmentally benign replacements for organic solvents to dissolve both polar and hydrophobic compounds.

The characterization of the solutions of poly(1,1-dihydroperfluorooctyl acrylate), poly(FOA), has been described. Solution free radical polymerization in supercritical CO2 has been performed to prepare two samples of poly(FOA) and the solutions were analyzed by small-angle neutron scattering spectroscopy. The molecular weight, radius of gyration and second virial coefficient were obtained.