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Inorganic fullerene-like (IF) nanotubes constructed from layered metal chalcogenides are of particular significance because of their excellent physical properties and potential application in wide fields. But very few previous studies were focused on the IF nanotubes of layered III-VI semiconductor. Therefore we investigate the preparation, structure and photoluminescence (PL) properties of GaS nanotube (an important III-VI semiconductor IF nanotube). A simple method is introduced to prepare GaS multi-walled nanotubes for the first time by annealing the natural lamellar precursor in Ar. The reaction temperature is crucial for the formation of nanotube. A suitable temperature range is 500-850 °C. Bulk quantities of GaS nanotubes with diameters of 30-150 nm and lengths up to ten micrometers were produced. Some of these nanotubes show corrugated and interlinked structure and form many segments, demonstrating a bamboo-like structure. As compared to bulk materials, the obvious distinction of the products in PL spectra at liquid nitrogen temperature of 77 K was due to the structure variety. [ABSTRACT FROM AUTHOR]

ZnO nanowire attracted nanosheets, nanocartridges and hexagonal nanotowers are fabricated by evaporation of ZnS in the presence of trace oxygen under controlled conditions. The nanosheet has an irregular structure, and nanowires sprout from the flange of the nanosheet. The nanocartridge has one row of prismatic nanorods grown on the (0001) surface of the ZnO nanohelts. The hexagonal nanotower, which grows along the c axis, shows an interesting layer structure and seems to forrn by piling up hexagonal ZnO nanocrystals layer on layer. These nanomaterials might have potential applications in optoelectronics. [ABSTRACT FROM AUTHOR]

By using the Langmuir–Blodgett (LB) technique, well-defined molecular layers of 2,9,16-tri(tert-butyl)-23-(10-hydroxydecyloxy)phthalocyanine were fabricated. These LB films have been employed to modify an anode surface of organic light-emitting devices. The insertion of LB films between an indium tin oxide (ITO) and hole-transport layers leads to an increase in device efficiency as a result of an improvement of the balanced carrier injection. An external quantum efficiency of 0.88% and a brightness of 10840 cd/m[sup 2] for a device with a structure of ITO/two LB layers/N,N[sup ′]-diphenyl-N,N[sup ′]-bis(3-methylphenyl)-1,1[sup ′]-biphenyl-4,4[sup ′]-diamine (TPD)/tris(8-hydroquinolinato)aluminium (Alq[sub 3])/Al were obtained, while the external quantum efficiency and brightness for the device without LB layers of ITO/TPD/Alq[sub 3]/Al were 0.51% and 5744 cd/m[sup 2], respectively. [ABSTRACT FROM AUTHOR]

New fluorene-linked conjugated polyquinoxaline and polyquinoline possess adequate optical transparency, excellent thermal stability and good processability. Degenerate four-wave-mixing measurements on these polymers yield nonresonant third-order susceptibilities as high as 1.1 × 10[SUP-10] esu and nonresonant second-order hyperpolarizabilities per repeated unit as high as 2.0 × 10[SUP-31] esu. The large nonlinearity originates from the high electron delocalization due to the planar rigid structure of the fluorene ring and the imine nitrogen of quinoxaline and quinoline. [ABSTRACT FROM AUTHOR]

The availability of high quality cDNA libraries is often crucial to the successful identification and characterization of genes. The concepts and potential pitfalls of constructing cDNA libraries are presented. Various applications requiring high quality cDNA libraries are outlined, including large-scale single pass sequencing of cDNA clones to generate expressed sequence tags (ESTs) and differential screening of cDNA libraries. The usefulness of combining such approaches for the discovery of novel disease-related and cardiovascular-based ESTs (CVBest) is discussed. [ABSTRACT FROM AUTHOR]

Nanofluids were obtained by filling carbon nanotubes (CNTs) with toluene using supercritical fluid technology. The method reported here should open a novel route to developing nanoscale chemical reactions using CNTs as nanoreactors. [ABSTRACT FROM AUTHOR]

Highly aligned amorphous SiO[SUBx] nanowires with lengths of up to several hundred microns were synthesized by using a millimeter-sized droplet of elemental gallium as a catalyst. Gallium displays highly catalytic activity for the growth of SiO[SUBx] nanowires. Some novel patterns of aligned SiO[SUBx]nanowires, including honeycomb-like and spindle-like structures, were observed. These SiO[SUBx] nanowires are expected to be used in nanooptics and reinforcing composites. [ABSTRACT FROM AUTHOR]

Abstract. Honeycomb-like alignments of carbon nanotubes were prepared by pyrolysis of a metal phthalocyanine at 950 Celsius in an Ar/H[sub 2] flow. A simple synthetic method has been developed for a large-scale synthesis of aligned carbon nanotubes normal to a substrate surface. [ABSTRACT FROM AUTHOR]

A novel kind of supramolecular polymer filament with a diameter of 2–5 µm was artificially synthesized, which is in fact a bundle of self‐assembled nanotubes with a diameter of about 40 nm. The filament can be drawn from a special alkaline aqueous solution directly and free standing in room temperature, which has never been performed earlier. A microtensile tester was developed with the aid of an electronic balance to investigate the mechanical properties of the new filament. Monotonic and load–unload tensile tests were performed, respectively. The maximum tensile strength and the elastic modulus of the filament were 23.8 MPa and 1.9 GPa, respectively, which were higher than previous supramolecular polymers and comparable to some covalent‐linked polymers. [ABSTRACT FROM AUTHOR]