Carbonaceous mesophases are liquid crystalline precursor materials that can be spun into high performance carbon fibers using the conventional melt spinning process. Carbon fiber property optimization requires a better understanding of the principles that control the structure development during the fiber formation processes and the rheological processing properties. This work presents the elas...

We used near-edge x-ray absorption fine structure (NEXAFS) spectroscopy to link the orientational bond order at three carbonaceous surfaces-rubbed polyimide, ion beam-irradiated polyimide, and ion beam-irradiated diamondlike carbon films-with the direction of liquid crystal (LC) alignment on these surfaces. We show that, in general, LC alignment can be created on any carbonaceous substrate by i...

The applications of carbon nanotubes (CNTs) as catalysts have attracted much interests in catalysis community due to their unique porous microstructure and chemical properties. One of the promising results is the use of CNTs in the oxidative dehydrogenation (ODH) of ethylbenzene to styrene [1,2]. However, only few works were reported on the use of CNTs or other carbonaceous materials to catalyz...

Surface- and volume-limited chemical reactions on and in atmospheric aerosol particles cause growth while changing organic composition by 13 to 24% per day. Many of these particles contain carbonaceous components from mineral dust and combustion emissions in Africa, Asia, and North America and reveal reaction rates that are three times slower than those typically used in climate models. These s...

2. This study shows a heating rate of +0.003-0.005K/day (Line 434) due to carbonaceous aerosols near the tropopause, and it is only 1 to 2% of total atmospheric heating rate (âĹij0.2 to 0.5 K/day). What is the uncertainness of the atmospheric heating rates at the UTLS? Gettelman et al. (2004, Figure 4) suggests that the uncertainties from different radiative transfer models is on the order of +...

Four dipeptides derived from phenylalanine were synthesized, which can self-assemble into twisted nanoribbon in deionized water. The handedness of the organic self-assemblies was controlled by the chirality of the phenylalanine at the terminals. Coiled 4,4′-biphenylene bridged polybissilsesquioxane tubular nanoribbons were prepared using the organic self-assemblies as the templates. The circula...

A new type of carbonaceous chondrite, the Tagish Lake meteorite, exhibits a reflectance spectrum similar to spectra observed from the D-type asteroids, which are relatively abundant in the outer solar system beyond the main asteroid belt and have been inferred to be more primitive than any known meteorite. Until the Tagish Lake fall, these asteroids had no analog in the meteorite collections. T...