Solid state studies in ceramic alloys Quarterly progress report, 1 Jun. - 31 Aug. 1969

Solid state characteristics of ceramic alloy

The economic geography of trade, production and income : a survey of empirics.

This paper surveys the empirical literature on the economic geography of trade flows, factor prices, and the location of production. The discussion is structured around the empirical predictions of a canonical theoretical model. We review empirical evidence on the determinants of trade costs and the effects of these costs on trade flows. Geography is a major determinant of factor prices, and access to foreign markets alone is shown to explain some 35% of the cross-country variation in per capita income. The paper documents empirical findings of home market (or magnification) effects, suggesting that imperfectly competitive industries are drawn more than proportionately to locations with good market access. Sub-national evidence establishes the presence of industrial clustering, and we examine the roles played by product market linkages to customer and supplier firms, knowledge spillovers, and labour market externalities.

Bonding, structure and mechanical behavior of vanadium carbide single crystals

Bonding, structure, and mechanical behavior of vanadium carbide single crystal

Use of Hydration Inhibitors to Improve Bond Durability of Aluminum Adhesive Joints

An investigation is conducted of the mechanisms by which nitrilotris methylene phosphonic acid (NTMP) and related compounds are adsorbed onto oxidized aluminum surfaces to inhibit hydration and increase the durability of adhesive bonds formed with inhibitor-treated panels. P - O - Al bonds are identified as the basis of adsorption, and it is found that water initially adsorbed onto the etched aluminum surfaces is displaced by the NTMP. The hydration of the NTMP-treated surfaces occurs in three stages, namely the reverisble physisorption of water, the slow dissolution of NTMP followed by rapid hydration of the freshly exposed Al2O3 to AlOOH and further hydration of the surface to Al(OH)3. Five properties of an ideal inhibitor are identified

Atomistic mechanisms for the ordered growth of Co nano-dots on Au(788): comparison of VT-STM experiments and multi-scaled calculations

Hetero-epitaxial growth on a strain-relief vicinal patterned substrate has revealed unprecedented 2D long range ordered growth of uniform cobalt nanostructures. The morphology of a Co sub-monolayer deposit on a Au(111) reconstructed vicinal surface is analyzed by Variable Temperature Scanning Tunneling Microscopy (VT-STM) experiments. A rectangular array of nano-dots (3.8 nm x 7.2 nm) is found for a particularly large deposit temperature range lying from 60 K to 300 K. Although the nanodot lattice is stable at room temperature, this paper focus on the early stage of ordered nucleation and growth at temperatures between 35 K and 480 K. The atomistic mechanisms leading to the nanodots array are elucidated by comparing statistical analysis of VT-STM images with multi-scaled numerical calculations combining both Molecular Dynamics for the quantitative determination of the activation energies for the atomic motion and the Kinetic Monte Carlo method for the simulations of the mesoscopic time and scale evolution of the Co submonolayer

The process of irreversible nucleation in multilayer growth. II. Exact results in one and two dimensions

We study irreversible dimer nucleation on top of terraces during epitaxial growth in one and two dimensions, for all values of the step-edge barrier. The problem is solved exactly by transforming it into a first passage problem for a random walker in a higher-dimensional space. The spatial distribution of nucleation events is shown to differ markedly from the mean-field estimate except in the limit of very weak step-edge barriers. The nucleation rate is computed exactly, including numerical prefactors.Comment: 22 pages, 10 figures. To appear in Phys. Rev.

The feminisation of British neurology: implications for workforce planning.

As in other hospital specialties, an increasing proportion of neurology trainees are female. To predict the workforce implications it is necessary to determine what life choices future neurologists will make. A questionnaire survey of life choices was administered to neurology consultants and trainees, general medical senior house officers, and medical students. Of the 344 respondents, 3% of specialist registrars (SpRs) and 4.6% of consultants work part time. Eighty-seven per cent of female and 22% of male junior doctors plan to work part time for, on average, 7.5 and 1.5 years respectively. Thirty percent of consultants also plan to work part time. A number of SpRs (14.3%) and consultants (6%) have taken a career break while 37.5% of SpRs and 18.2% of consultants are planning a career break. The changing demands of both sexes will have a greater impact on the neurology workforce than the increasing proportion of women alone. Increased part-time working will require additional trainees to ensure service requirements are met

The rotationally-resolved absorption spectrum of formaldehyde from 6547 to 6804 cm(-1)

The room temperature absorption spectrum of formaldehyde, H2CO, from 6547 to 6804 cm(-1) (1527-1470 nm) is reported with a spectral resolution of 0.001 cm(-1). The spectrum was measured using cavity-enhanced absorption spectroscopy (CEAS) and absorption cross-sections were calculated after calibrating the system using known absorption lines of H2O and CO2. Several vibrational combination bands occur in this region and give rise to a congested spectrum with over 8000 lines observed. Pressure broadening coefficients in N-2, O-2, and H2CO are reported for an absorption line at 6780.871 cm(-1) and in N-2 for an absorption line at 6684.053 cm(-1)