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A novel modified carbon nanotube paste electrode of 2-(4-oxo-3-phenyl-3, 4-dihydro-quinazolinyl)-N'-phenyl-hydrazinecarbothioamide (2PHC) was fabricated, and the electrooxidation of epinephrine (EP), norepinephrine (NE), and their mixture has been studied using electrochemical methods. The modified electrode displayed strong catalyric function for the oxidation of EP and NE and resolved the overlap voltammetric response of EP and NE into two well-defined voltammetric peaks of about 240 mV with square wave voltammetry (SWV). A linear response in the range of (5 x [10.sup.-8])-(5.5 x [10.sup.-4]) M with a detection limit (S/N = 3) of 9.4 nM for EP was obtained.

Nanofibrils of ultrahigh molecular weight syndiotactic polystyrene (sPS) are prepared in a silica nanotube reactor (SNTR) by using a metallocene catalyst in conjunction with methylaluminoxane cocatalyst. The sPS synthesized in the SNTR has ultrahigh molecular weight with a large fraction of molecular weight polymers.

This paper reports the molecular imprinting at the walls of highly uniform silica nanotubes for the recognition of 2,4,6-trinitrotoluene (TNT). It has been demonstrated that TNT templates were efficiently imprinted into the matrix of silica through the strong acid-base pairing interaction between TNT and 3-aminopropyltriethoxysilane (APTS). TNT-imprinted silica nanotubes were synthesized by the gelation reaction between APTS and tetraethylorthosilicate (TEOS), selectively occurring at the porous walls of APTS-modified alumina membranes. The removal of the original TNT templates leaves the imprinted cavities with covalently anchored amine groups at the cavity walls. A high density of recognition sites with molecular selectivity to the TNT analyte was created at the wall of silica nanotubes. Furthermore, most of these recognition sites are situated at the inside and outside surfaces of tubular walls and in the proximity of the two surfaces due to the ultrathin wall thickness of only 15 nm, providing a better site accessibility and lower mass-transfer resistance. Therefore, greater capacity and faster kinetics of uptaking target species were achieved. The silica nanotube reported herein is an ideal form of material for imprinting various organic or biological molecules toward applications in chemical/biological sensors and bioassay.

Lanthanum atoms are introduced into carbon nanotubes with the help of fullerene cages as carry bags and are further transformed into atomic wires. Since the lanthanoid metals are encapsulated in the fullerene cage to form metallofullerene, this method can be used for all the metallofullerenes, generating atomic wires of transition or lanthanoid series metals inside carbon nanotubes (CNTs).

A first principle computational study about the water confined between prototypical nonpolar substrates like single-wall carbon nanotubes and graphene sheets is reported. The findings reveal that the perturbation induced by the presence of confining media is extremely local in liquid water and is determined by subtle electronic structure rearrangements occurring at the interface with the confining medium.

The fabrication of two kinds of Ce[O.sub.2] nanotubes with unique structures and morphologies by using Ce(OH)C[O.sub.3] nanorods as precursors is demonstrated.

A large number of studies are conducted to demonstrate and fabricate the highly ordered silicon (Si) nanotube (SiNT) arrays, which act as attractive matrix to accommodate macromolecules and help in direct electrochemistry of cytochrome c without any pretreatment. The result indicates that the SiNT arrays exhibit good biocompatibility, as well as a nanoscale hollow structure and hence can be used in the preparation of various Si-based biosensors and protein characterizations.

A new method that makes use of colloidal silica templates is demonstrated to fabricate porous three-dimensional architectures of carbon nanotubes (CNTs). Porous CNT membranes and three-dimensional carbon nanotube foams are obtained by treating these silica-CNTs structures with HF.

New capabilities for creating arrangements of single-walled carbon nanotubes SWNTs that could be useful for applications in thin-film electronics are introduced. It is stated that these techniques complement other reported approaches and may facilitate the use of SWNTs in practical devices.

A simple method to decorate that multiwalled carbon nanotubes (MWCNTs) with zinc sulfide nanospheres is developed. The method involves ultrasonic pretreatment and heat treatments of MWCNTs, zinc chloride, and thiourea in ethanol.

The template technique was used for the successful preparation of the double coaxial carbon nanotubes (CNT) composed of N-doped and B-doped multiwalls. By changing the CVD conditions it was shown that is possible to adjust the N or B fraction and respective thickness of N-doped and B-doped multiwalls.

The synthesis of shell-cross-linked organometallic nanotubes of silver that contain a polyferrocenylsilane (PFS) inner wall covered by a cross-linked network of polymethylvinylsiloxane chains is reported. The result showed that pretreatment of PFS with organic oxidants such as dichloromethane is the key step to obtain silver particles within the tubes in high yields and the resulting soluble peapod-like hybrid nanostructures may ultimately be useful for the fabrication of nanodevices.