The structural and electronic properties of sheets and nanotubes of boron are investigated using density functional theory. The calculations predict the stability of a novel reconstructed {1221} sheet over the idealized triangular {1212} sheet. Nanotubes formed by wrapping the half-metallic {1221} sheet show a curvature-induced transition in their electronic properties. Analysis of the charge d...

We have used a 3-GHz microwave host cavity to study the remarkable electronic properties of metallic, single-walled carbon nanotubes. Powder samples are placed in its magnetic field antinode, which induces microwave currents without the need for electrical contacts. Samples are shown to screen effectively the microwave magnetic field, implying an extremely low value of sheet resistance (< 10 μΩ...

A macrocyclic β-sheet peptide containing two nonapeptide segments based on Aβ(15-23) (QKLVFFAED) forms fibril-like assemblies of oligomers in the solid state. The X-ray crystallographic structure of macrocyclic β-sheet peptide 3 was determined at 1.75 Å resolution. The macrocycle forms hydrogen-bonded dimers, which further assemble along the fibril axis in a fashion resembling a herringbone pat...

The diffraction of light by a single subwavelength hole in a highly conductive metallic sheet is analyzed with a recently developed differential theory that is able to plot the nearly electromagnetic field. Using rigorous electromagnetic and phenomenological analysis, we show that a single subwavelength hole can excite surface-plasmon resonance that contributes greatly to extraordinary transmis...

Polymer-fullerene-based bulk heterojunction (BHJ) solar cells have many advantages, including low-cost, low-temperature fabrication, semi-transparency, and mechanical fl exibility. [ 1 , 2 ] However, there is a mismatch between optical absorption length and charge transport scale. [ 3 , 4 ] These factors lead to recombination losses, higher series resistances, and lower fi ll factors. Attempts ...

The full history of ice sheet and climate interactions is recorded in the vertical profiles of geochemical tracers in polar ice sheets. Numerical simulations of these archives promise great advances both in the interpretation of these reconstructions and the validation of the models themselves. However, fundamental mathematical shortcomings of existing models subject tracers to spurious diffusi...

To simply reduce HAuCl(4) using 2-thiophenemethanol in an aqueous solution at room temperature, a novel metallic Au nanostructure with a high SERS activity was obtained. Flat sheet-like Au nanoleaves possessing many nanogap hotspots bound with a large percentage of high-index facets were obtained.

A novel two-dimensional→three-dimensional Cu(II) coordination polymer, {[Cu2(C10H14N4)5](NO3)4·4H2O} n , based on the 1,1'-(butane-1,4-di-yl)bis-(1H-imidazole) (biim) ligand and containing one crystallographically unique Cu(II) atom, has been synthesized under hydro-thermal conditions. The Cu(II) atom is coordinated by five N atoms from biim ligands, one of which has crystallographically impose...