Abstract: Methods for producing hydrogen using nanoparticles, a catalyst, and a source of electrons, such as bacteria and their nutrient source in a biological system, are carried out in an aqueous medium. The nanoparticles may be doped with a plurality of isovalent and/or non-isovalent dopants.

Abstract: Methods for producing hydrogen using nanoparticles, a catalyst, and a source of electrons, such as bacteria and their nutrient source in a biological system, are carried out in an aqueous medium. The nanoparticles may be doped with a plurality of isovalent and/or non-isovalent dopants.

Abstract: A free-standing membrane comprises a plurality of vertically aligned carbon nanotubes, each of the plurality of vertically aligned carbon nanotubes having a first terminus at a first side of the membrane and a second terminus at a second side of the membrane. The first and second terminuses are exposed. The free-standing membrane comprises a non-conducting, inert filler material disposed in the interstitial space between the nanotubes such that a barrier to electron, proton, and/or ion transport is formed, and so that conduction of electrons, protons, and/or ions only occurs through the plurality of vertically aligned carbon nanotubes and not through the inert filler material. Methods for fabricating the membrane comprise nanotube growth, epoxy coating, and exposure of the terminuses of the nanotubes.

Abstract: A nanoparticle comprising a ternary core comprising Cd, Zn and Se; and a shell comprising Zn and Y, wherein Y is Se or S or a combination thereof. The Cd and Zn are non-homogenously distributed in the ternary core such that the nanoparticle exhibits continuous photoluminescence for extended periods of time. Also provided are methods for preparing and methods of using the nanoparticles which exhibit continuous photoluminescence.

Abstract: A sensor chip that includes: a fluorescence quenching surface; a nucleic acid probe that contains first and second ends with the first end bound to the fluorescence quenching surface, a first region, and a second region complementary to the first region, the nucleic acid probe having, under appropriate conditions, either a hairpin conformation with the first and second regions hybridized together or a non-haipin conformation; and a first fluorophore bound to the second end of the first nucleic acid molecule. When the first nucleic acid molecule is in the hairpin conformation, the fluorescence quenching surface substantially quenches fluorescent emissions by the first fluorophore; and when the first nucleic acid molecule is in the non-hairpin conformation, fluorescent emissions by the fluorophore are substantially free of quenching by the fluorescence quenching surface.