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The low-temperature solvo-thermal syntheses of single-phase titania from Ti[Cl.sub.4] in ketones capable of performing aldol condensation reaction are presented.

The layered double hydroxides (LDHs) have their intercalated anions selected and exchanged by guest-host chemistry to prevent sintering of the metal nanoparticles (NPs), where the metal NPs on Mo[O.sub.4.sup.2-] intercalated Fe/Mg/Al LDH flakes are used as the catalyst for the double helix growth of single-walled carbon nanotube arrays. The process has provided a general method to prepare thermally stable metal NPs catalysts with the desired size and density for catalysis and materials science.

The coexistence of acidic and basic O and N sites were functionalized via amination to characterize the samples of vapor grown carbon nanofibers (VGCNFs) modified by treatment of the oxidized CNFs with N[H.sub.3]. The results revealed the potential application of the N-containing nanocarbon materials obtained via amination in catalysis as well as electronic device materials.

The article discusses the synthesis of a metal-free phenanthrenequinone macrocyclic trimer, which can be used as an effective heterogeneous catalyst for the oxidative dehydrogenation of ethylbenzene. The various diketone-like groups are shown to act as the active sites in these reactions.

An emulsion engineering method to modulate pore length and morphological architecture of mesoporous materials is built in the complex alkane/P123/TEOS/[H.sub.2]O emulsion system. The effects of alkane solubilizates on pore length and particle morphology are investigated and the resulting short-pore materials are found to have the potential applications in the fields of adsorption/separation of biomolecules and inclusion chemistry of guest species.

Direct experimental evidence of facile reduction of Fe2O3 nanoparticles located inside the bores at 600 degree Celsius versus reduction of those on the outer surface of multi-walled carbon nanotubes (CNTs) at 800 degree Celsius is presented. This is the first example of CNT-confined metal particles obtained by direct reduction by CNTs, which proves that nanotubes provide a confined environment with unique electronic properties.

The article discusses the application of transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) and associated spectroscopic techniques to characterize solid state catalysts. It outlines the major characteristics of solid catalysts, and their challenges to instrumental developments. It notes the implementation of aberration correction on commercial TEM/STEM.

The article presents a review that examines the state of nanocarbons and explores the futuristic aspects of it in drafting plausible developments regarding a design of advanced catalysts. It informs that the aspects of nanocarbons are discussed as a support for both metal and metal oxides nanoparticles. It highlights that metal and metal oxide nanoparticles act as catalytic centers where catalytic properties are related to catalytic activities.

We evaluated, in vitro, the inflammatory and cytotoxic potential of soot particles from current low-emission (Euro IV) diesel engines toward human peripheral blood monocyte- derived macrophage cells. The result is surprising. At the same mass concentration, soot particles produced under low-emission conditions exhibit a much higher toxic and inflammatory potential than particles from an old diesel engine operating under black smoke conditions. This effect is assigned to the defective surface structure of Euro IV diesel soot, rendering it highly active. Our findings indicate that the reduction of soot emission in terms of mass does not automatically lead to a reduction of the toxic effects toward humans when the structure and functionality of the soot is changed, and thereby the biological accessibility and inflammatory potential of soot is increased. [ABSTRACT FROM AUTHOR]