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The (n,m) population distribution of single-walled carbon nanotubes obtained on supported CoMo catalysts is determined by photoluminescence and optical absorption. It is found that the (n,m) distribution can be controlled by varying the gaseous feed composition, the reaction temperature, and the type of catalyst support used.

A correlation function formalism is applied to compute the two-photon absorption spectrum of benzene and an expression for the average vibrational energy in the excited state is derived. Using harmonic Hamiltonians for the ground and excited electronic states, it is found that the theory agrees quantitatively with the experimentally observed sparsity of the thermal two-photon absorption spectrum as compared with the single-photon absorption spectrum.

Differential scanning calorimetry, one- and two-dimensional wide-angle X-ray diffraction (1D and 2D WAXD), and polarized light microscopy are applied to study the The liquid-crystalline (LC) phase structures and transitions of a combined main-chain/side-chain LC polymer (MCSCLCP). The polymer described as an MCSCLCP with a fascinating hierarchically ordered structure could be obtained when two separate components, one offering the 'jacketing' effect to the normally flexible backbone and the other with mesogens that form surrounding LC phases, are introduced simultaneously into the side chains.

Low-temperature scanning tunneling microscopy, molecular dynamics (MD) and density functional theory (DFT) calculations are used for examining self-assembly of the binary molecular system of pentacene and 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) on Ag(111). The results have shown that the formation of large-scale, highly periodic two dimensional supramolecular assemblies have depended on a combination specific and relatively strong molecule-substrate interactions with weak but directional intermolecular interactions.

The first example of achieving Hiyama couplings of aryl arenesulfonates is described. The desired C-C bond formation has proceeded under mild conditions with good functional group tolerance.

A computational approach is presented to address the structural characteristics of electron solvation and the nature of the forces that drive this solvation in a LiF ionic pair matrix.

A new strategy is used for fabricating surface nanotemplates featuring well-ordered nanocavity arrays made up by [C.sub.60] molecules, referred to as a [C.sub.60] nanomesh, which is formed by adjusting the binary molecular phases of [C.sub.60] and pentacene on Ag(111). The [C.sub.60] nanomesh has served as a effective template to selectively accommodate guest [C.sub.60] molecules at the nanocavities, thus leading to the formation of an ordered 2D [C.sub.60] array with a large intermolecular distance between the nearest neighboring [C.sub.60] on top of the [C.sub.60] nanomesh template.

The studies about metalated (Li, Na, K) and protonated dipeptides derivatives and their positive binding energies (PBEs) which are influenced by side-chain distance is reported. The results provide insight into the origin of regular ordering of amino acids when they form a filter in the [K.sup.+] channel protein.

Palladium-catalyzed Suzuki-Miyaura cross-coupling reaction of aryl tosylates with potassium aryl trifluoroborate in the presence of electron-rich phosphine ligand is described. A useful chemoselective coupling of an aryl chloride is shown in the presence of a tosyloxy group.

The Pd-catalyzed decoupling reactions which facilitates the synthesis of diversified 3,4-diarylated coumarins is described. The strategy was developed on the basis of different selectivities of 3-bromo-4-trifloxycoumarins and 3-bromo-4-tosyloxycoumarins in Suzuki-Miyaura cross-coupling.

Self-assembled functionalized aromatic thiols, oligophenylenes composed of building blocks of dimethoxy-substituted phenylenes, perfluoro-substituted phenylenes and a terminal thiol group, are used to tune the hole injection barrier of copper(II) phthalocyanine (CuPc) on Au(111). The molecular orientations of CuPc on self-assembled monolayer (SAM)/Au(III) have indicated an upright configuration of CuPc on SAMs, facilitating their effective incorporation in organic field-effect transistor (OFET) and other planar organic devices.

The growth behaviors of C60 molecules on SiC nanomesh at room temperature is systematically investigated using in situ scanning tunneling microscopy. After deposition of 1 ML C60, a complete layer of hexagonally close-packed C60 molecules forms on top of the SiC nanomesh.

Field emission studies are conducted on as-produced CoMoCAT single-walled carbon nanotube/silica composites with controlled nanotube diameter and bundle size. The result reveals that the as-produced nanotube material does not need to be separated from the high-surface area catalyst to be an effective electron emitter.

The second series of flexible shape-modified nucleosides is introduced. The designs and synthesis of novel shape-modified nucleosides explores the fundamental aspects of nucleic acid structure, function, stability, and investigates enzyme binding site parameters.

The study of unfolding and refolding processes of SARS_S1b induced by heating and a chemical denaturant using circular dichroism (CD) spectroscopy, tryptophan fluorescence, and stopped-flow spectral techniques are reported. The CD spectra are not dependent on temperature, suggesting that the secondary structure of SARS_S1b has a relatively high thermal stability.