Nanocrystalline silicon (n-Si) is formed in a silicon dioxide thin-film matrix by ion implantation followed by thermal annealing in forming gas at 1100 °C for 1 hour. The ion implantation is performed using multiple implants with different implantation energies and doses to create a quasi-flat concentration of silicon atoms throughout the silicon dioxide film. These samples are then analyzed using spectroscopic ellipsometry to characterize their linear optical properties. Implantations with small doses (5 × 1020 Si atoms/cm3) increase the refractive index by a small amount (δn∼0.006 at 600nm), while implantations with moderate dose (5 × 1021 Si atoms/cm3) have a larger increase in refractive index and exhibit optical absorption above ∼1.9 eV (650 nm).

Layered orthogneisses of the Oygarden Islands preserve evidence for four high-grade deformation events (D1 to D4). Archaean D1 and D2 structures are only patchily preserved due to extensive recrystallization during D3 and D4, which represent effects of the c. 1000 Ma Rayner Structural Episode. Ductile thrusting at middle to lower crustal levels occurred during D3, which is separated into two mutually cross-cutting phases based on structural geometry; the two phases represent changes in finite strain that developed during progressive deformation. East-directed transport during D3a developed subhorizontal thrusts that contain co-axial, east-trending F3a folds and L3a lineations. Buckling as a consequence of constriction in thrust duplexes developed upright F3b folds coaxial to F3a folds, and steeply south-dipping D3b shear zones. Garnet–clinopyroxene- and garnet–orthopyroxene-bearing assemblages in mafic lithologies, and garnet–sillimanite-bearing assemblages in pelitic lithologies reflect D3 conditions of P=9 kbar and T=800–850 °C. The well-exposed D3 duplex structures indicate that shortening of the lower crust may be accommodated by extensive strain partitioning to develop contemporary kilometre-scale thrust stacking and ductile flow.

This paper seeks to define and explain financial reinsurance, a type of reinsurance growing rapidly in the general insurance market. It provides criteria for underwriters and actuaries to understand the degree of risk transfer involved and the limitations on that risk transfer. It seeks to set out criteria, applicable to both insurer and reinsurer, for estimating reserves where financial reinsurance covers are involved and for compliance with supervisory requirements. Several examples are given of typical financial reinsurance contracts currently in use.

We describe the evolution and microstructure of Si/CoSi2/Si (100) and (111) heterostructures formed by Co+ ion implantation into Si substrates (“mesotaxy”), followed by high temperature annealing. It is shown that the CoSi2 precipitate nucleation and ripening process, and eventual coalescence into buried layers, is controlled by interfacial structure and energetics. Understanding and control of these processes allows for the first time synthesis of otherwise almost identical CoSi2 buried layers with either twinned or untwinned CoSi2/Si(111) interfaces.

To define the pathology in cases of non-Alzheimer primary degenerative dementia (non-AD PDD), we have studied autopsies from four medical centres accessioned in consecutive years since 1976. Neurochemical studies of the basal forebrain-cortical (BF-C) cholinergic system have been conducted in cases from which frozen tissue was available. Twenty-two cases (mean age 70 years, range 47-86) in which the history was consistent with PDD, but which did not meet anatomic criteria for AD, were selected. Approximately 70 cases of PDD, which were accessioned in the same years and met the anatomic criteria for AD, were excluded. The pathologic findings permitted a classification into six groups: Lewy body disease (LBD), 4 cases; Pick's disease, 6 cases; cortical degeneration with motor neuron disease (CDmnd), 2 cases; hippocampal and temporal lobe sclerosis, 3 cases; few or nonspecific abnormalities, 5 cases; other disorders, 2 cases. Our findings suggest that LBD and Pick's disease account for a large proportion of cases of non-AD PDD in the presenile age group, but that a large number of other disorders occasionally present as PDD. Careful examination of the motor systems, as well as cerebral structures relate' to cognitive function, is important in the neuropathologic evaluation. Lesions of the BF-C cholinergic system have been most consistent and severe in LBD, and have not been identified in CDmnd.

Several different insulating substrates were coated with various metal films and ion beam irradiated using either Xe or Kr ions. These were then examined by Rutherford backscattering spectroscopy and scanning electron microscopy to determine if interfacial mixing had taken place. These results were compared with the sign of the reaction enthalpy of the metal and substrate to test the proposition that metals mix on insulators if the reaction enthalpy is negative and do not mix if it is positive. The enthalpy rule is in general valid. Two exceptions were found: Cr on Si02 and Zr on Al203; however, these exceptions contain ambiguous features.

Irradiation with a light, reactive ion was found to produce no mixing.

Ion beam irradiation of metal film/SiO2 interfaces causes reactions when the metals are those chemically capable of reducing SiO2. These reactions result in the formation of metal rich silicides in the region of the interface and an increase in the adhesion of the film to the substrate. For other nonreactive metals ion irradiation causes lateral transport of metal atoms resulting in the formation of an island structure. The results obtained by ion irradiation are compared with previous studies of high temperature thermal processing of metal films on SiO2.