In an urban-transit bus, fueled by biodiesel in Toledo, Ohio, single inhalable particle samples in October 2008 were collected and detected by scanning electron microscopy and energy dispersive X-ray spectrometry (SEM/EDS). Particle size analysis found bimodal distribution at 0.2 and 0.5 microm. The particle morphology was characterized by 14 different shape clusters: square, pentagon, hexagon,...

Synthetic methodology is considered a holy grail in both organic chemistry and materials science. Over the past few decades, researchers have explored graphene-type molecules (or nanographenes) through classic Scholl oxidative cyclodehydrogenation. Despite successes achieved with various nanographenes, development of new methods to synthesize these highly desired lags behind. Herein, we develop...

Combining total energy and molecular dynamics calculations, we explore the suitability of nanotube-based hooks for bonding. Our results indicate that a large force of 3.0 nN is required to disengage two hooks, which are formed by the insertion of pentagon-heptagon pairs in a (7,0) carbon nanotube. Nanohooks based on various nanotubes are resilient and keep their structural integrity during the ...

Confocal Raman spectral imaging results are presented for a metal-to-semiconductor intramolecular junction (IMJ) on an isolated carbon nanotube. Spectra observed at the junction are consistent with the symmetry lowering expected from the occurrence of pentagon-heptagon defects to produce the chirality shift. The IMJ transition zone is sharp and preserves the nanotube diameter. These results hav...

Using scanning tunneling microscopy with Fe-coated W tips and first-principles calculations, we show that the interface of epitaxial graphene/SiC(0001) is a warped graphene layer with hexagon-pentagon-heptagon (H(5,6,7)) defects that break the honeycomb symmetry, thereby inducing a gap and states below E(F near the K point. Although the next graphene layer assumes the perfect honeycomb lattice,...

Plastic relaxation of carbon nanotubes under tension and at high temperature is described in terms of dislocation theory and with atomistic computer simulations. It is shown how the glide of pentagon-heptagon defects and a particular type of their pseudoclimb, with the atoms directly breaking out of the lattice, work concurrently to maintain the tube perfection. Derived force diagram quantifies...

Grain boundaries consisting of dislocation cores arranged in a periodic manner have well-defined structures and peculiar properties and can be potentially applied as conducting circuits, plasmon reflectors and phase retarders. Pentagon-heptagon (5-7) pairs or pentagon-octagon-pentagon (5-8-5) carbon rings are known to exist in graphene grain boundaries. However, there are few systematic experim...

The cartoon figure on the cover image is Monkey King, who a character in classical Chinese novel “Journey to West”. He has 72 polymorphic transformations. As shown cartoon, he only needs blow breath and can create lot of little monkeys. p-Terphenylene-bridged NiII porphyrin dimer, which similar gave syn- anti-doubly heptagon-fused dimers, spiro-pentagon-bridged chlorin doubly octagon-fused dime...

the adsorption of a number of amino acids on a defected single-walled carbon nanotube (swcnt) isinvestigated by using the density-functional theory (dft) calculations. the adsorption energies andequilibrium distances are calculated for various configurations such as amino acid attaching to defectsites heptagon, pentagon and hexagon in defective tube and also for several molecular orientationswi...