Nanowalls, a new nanostructural morphology of carbon, grow instead of nanotubes under microwave plasma‐enhanced CVD conditions on substrates electrically disconnected from the lower electrode. While not fully understood, the formation of nanowalls (see Figure for top view) appears to depend on the local electric field. Due to their large surface, nanotubes may find applications in field emission displays and energy storage devices.

We examined the uptake of three hydrophobic chemicals, TCB (1,2,4-trichlorobenzene), PeCB (1,2,3,4,5-pentachlorobenzene), and HCBP (2,2Ј,4,4Ј,6,6Ј-hexachlorobiphenyl), by unfed juvenile rainbow trout (Oncorhynchus mykiss) in test aquaria containing sediments from the Fraser River. Our working hypothesis was that the low organic carbon content of the Fraser River sediments would increase the bioavailability of xenobiotics associated with these sediments. The test chemicals and sediments were introduced into aquaria 9 d before the fish were introduced. Measured concentrations of the chemicals in the bottom sediments, suspended sediments, and filtered (0.45 m) water suggested that the test system had reached a quasiequilibrium state by day 9. Subsequently, a 6-d exposure of fish in the test aquaria resulted in a significant accumulation of the test chemicals in the fish tissues and significant reductions in the chemical concentrations of the bottom sediments, suspended sediments, and filtered water. Mass balance analysis suggests that the appearance of HCBP and PeCB in the fish after 6 d could not be accounted for solely by the amount of chemical dissolved in the water at the time when the fish were introduced. A large unaccounted-for fraction of TCB, possibly due to fish metabolism, precluded an accurate mass balance analysis for this chemical. Because chemical uptake in fish with the pharynx plugged (to eliminate the gut uptake route) was similar to that in control fish and because direct access to bottom sediments did not alter chemical uptake, we conclude that hydrophobic chemicals such as PeCB and HCBP associated with suspended sediments from the Fraser River can readily desorb and be taken up across the gill.

We report the observations of dewetting of resist/metal bilayers in a resist stripping process of nanofabrication in O2 plasma. The initiation of the dewetting process is tentatively associated with local heating caused by surface plasmon induced in metallic nanoparticles or nanowires. The surface patterns thus formed differ substantially from all the dewetting patterns reported so far, and they resemble trees at micrometer scale. The possible mechanism for the formation of this kind striking patterns is discussed and its implication to future nanoelectronics manufacturing is addressed.

ABSTRATWe describe the growth of magnetic nanostructures on carbon nanotube templates. The nanotubes were grown by microwave plasma enhanced chemical vapour deposition. The as grown nanotubes were aligned reasonably well around the substrate normal directions. Although the nanotubes were quite straight, there were still some bent and tilt as revealed by the scanning electron microscope observations. Magnetic field has been used to re-align or re-assemble the nanotubes before they were used as the templates to grow magnetic nanostructures. Depending on whether there is a magnetic particle on the top tip of each nanotube and the density of the nanotubes, there are two different consequences of applying a magnetic field to the nanotubes. For nanotubes with magnetic particles attached to their top tips, the post-growth treatment by the magnetic field resulted in re-assembly of the nanotubes into micro-umbrella type of structures. For those without magnetic particles, however, the effect of magnetic field treatment is negligible; but after the deposition of thin magnetic layers, the field treatment made the nanotubes much straighter than what they originally were and aligned almost vertically to the substrates. The re-aligned or re-assembled nanotubes were used as the templates to grow magnetic nanostructures. It was found that most of the magnetic nanostructures exhibited characteristics similar to those of magnetic nanowires.