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Modification of the spark erosion technique (1, 2) for the synthesis of fullerenes has led to the discovery (3) and preparation of macroscopic quantities of carbon nanotubes (4). HREM images [...], Previous high-resolution electron microscopy (HREM) observations of the carbon nanotubes have led to a 'Russian doll' structural model that is based on hollow concentric cylinders capped at both ends. The structures of the carbon nanotubes and particles were characterized here by bulk physical and chemical property measurements. The individual nanostructure is as compressible as graphite in the c axis, and such nanostructures can be intercalated with potassium and rubidium, leading to a saturation composition of '[MC.sub.8]' These results are counter to expectations that are based on a Russian doll structure. HREM after intercalation with potassium and deintercalation indicates that individual nanoparticles are a 'paper-mache' of smaller graphite layers. Direct current magnetization and electron spin resonance measurements indicate that the electronic properties of the nanostructures are distinctly different from those of graphite. Although the nanostructures have distinct morphologies and electronic properties, they are highly defective and have a local structure similar to turbostratic graphite.

We present a series of 8.4-GHz very-long-baseline radio interferometry images of the nucleus of Centaurus A (NGC5128) made with a Southern Hemisphere array, representing a 3.33-year monitoring effort. The nuclear radio jet is [approximate]50 milliarcseconds in extent, or at the 3.5-megaparsec distance of NGC5128, [approximate] 1 parsec in length. Sub-luminal motion is seen and structural changes are observed on time scales shorter than 4 months. High-resolution observations at 4.8 and 8.4 GHz made in November 1992 reveal a complex morphology and allow us to unambiguously identify the self-absorbed core located at the southwestern end of the jet.

The study of high-resolution radio observations of second Galactic superluminal radio source GRO J1655-40 reveals the relativistic motion between two components of the radio source. The two components are moving away from each other at speeds, greater than that of the speed of light. This relativistic motion between the two objects is attributed to the ejection of material from these two astronomical objects, at relativistic speeds in the course of accretion into a blackhole.

Intercalation of ammonia into K3C60 yields (NH3)K3C60 with an orthorhombic distortion of the face-centered cubic (f.c.c.) structure. The f.c.c. has one K and one NH3 per octahedral site. Ammonia intercalation does not appear to change the extent of the charge transfer from K to C60, but the compound is not superconducting. This could be a result of electron localization resulting from structural distortion, leading to the conclusion that the creation of C60-based superconductors is dependant on the change in symmetry of the unit cell as well as the cell size.

A study of the structure of alkali-intercalated A(sub x)C60 fullerides (where A is an alkali metal and x = 2,3,4,6) is reported. The study protocol involved the use of 87-Rb nuclear magnetic resonance studies of Rb3C60. The results revealed the expected ratio of two tetrahedral and one octahedral Rb per C60 at 440 degrees Kelvin. However, an additional resonance appears at temperatures below 370 degrees Kelvin which arises from a second type of tetrahedral Rb+ site. Two models are presented to explain this phenomenon.

The alkali-metal fulleride Na2CsC60 is a f.c.c. superconductor with and a value of 14.132 angstroms and a transition temperature (Tc) of 10.5 K. Since cations can occupy the octahedral site of the fulleride, attempts were made to introduce molecular ammonia (NH3) to Na2CsC60. Ammonia was introduced by exposing the sample to 380 torr of NH3 gas distilled from a sodium/liquid-ammonia solution through a vacuum manifold. Introduction of the ion resulted in an increase in a to 14.473 angstroms and an increase in Tc to 29.6K.

THE RECENT DISCOVERY THAT ELECtrically conducting [1] and superconducting [2, 3] alkali fullerides with general formula [M.sub.x][C.sub.60] (M = K, Rb, Cs) can be prepared by reacting solid [C.sub.60] [buck-minsterfullerene [...]

Thermal and photoconductive charge transport processes are studied in Ta2O5 metal-oxide-metal capacitors fabricated by anodization, reactive sputtering, and chemical vapor deposition. The results obtained from each of the three methods are similar when compared with films that have the same thickness and electrodes.

Processing Techniques for the 93 K Superconductor Ba.sub.2.YCu.sub.3.O.sub.7 THE DISCOVERY OF SUPERCONDUCTIVITY IN COPPER OXide-based ternary and quaternary systems by J. G. Bednorz and K. A. Muller has led to [...]