Recovery of aluminum from composite propellants

Aluminum was recovered from solid rocket propellant containing a small amount of oxidizer by depolymerizing and dissolving propellant binders (containing functional or hydrolyzable groups in a solution of sodium methoxide) in an alcohol solvent optionally containing an aliphatic or aromatic hydrocarbon co-solvent. The solution was filtered to recover substantially all the aluminum in active form

The interface between transactional and relational orientation in small service firm's marketing behaviour

This paper presents and discusses findings of a cross-country study of small service firm marketing behavior. These findings demonstrate that small service firms are flexible in the marketing approaches that they adopt. They reveal that such firms are transactional and relational orientated in their marketing activities and that for growing firms, marketing activities are used to create short-term transactions and form relations with key stakeholders. This finding implies that transactional and relationship marketing should be regarded as complementary. The findings presented also demonstrate that the marketing approach selected by participating small firms is determined by a range of customer characteristics of which repeat business is only one. An integrated framework containing elements of transactional and relational approaches is proposed as an appropriate way of describing the marketing behaviours of investigated firms

Time-decoupled high order continuous space-time finite element schemes for the heat equation

Copyright © by SIAMIn Comput. Methods Appl. Mech. Engrg., 190 (2001), pp. 6685—6708 Werder et al. demonstrated that time discretizations of the heat equation by a temporally discontinuous Galerkin finite element method could be decoupled by diagonalising the temporal ‘Gram matrices’. In this article we propose a companion approach for the heat equation by using a continuous Galerkin time discretization. As a result, if piecewise polynomials of degree d are used as the trial functions in time and the spatial discretization produces systems of dimension M then, after decoupling, d systems of size M need to be solved rather than a single system of sizeMd. These decoupled systems require complex arithmetic, as did Werder et al.’s technique, but are amenable to parallel solution on modern multi-core architectures. We give numerical tests for temporal polynomial degrees up to six for three different model test problems, using both Galerkin and spectral element spatial discretizations, and show convergence and temporal superconvergence rates that accord with the bounds given by Aziz and Monk, Math. Comp. 52:186 (1989), pp. 255—274. We also interpret error as a function of computational time and see that our high order schemes may offer greater efficiency that the Crank-Nicolson method in terms of accuracy per unit of computational time—although in a multi-core world, with highly tuned iterative solvers, one has to be cautious with such claims. We close with a speculation on the application of these ideas to the Navier-Stokes equations for incompressible fluids

Managing the Moral Implications of Advice in Informal Interaction

What does advice giving look like among family members? Most conversation analytic research on advice has been in institutional settings, which constrain what speakers can do. Here we analyze advice in the apparently freer environment of telephone calls between mothers and their young adult daughters. We concentrate on how the advice is received. Our analysis shows that the position of “advice recipient” is a potentially unwelcome identity to occupy because it implies one knows less than the advice giver and indeed that one may be somehow at fault. Advice can be resisted, but choosing to do so seems to depend on what the interactional costs would be. We discuss the implications for studying advice and promoting advice acceptance as well as the way relationality more generally can be constituted in talk

Variations in propagation delay times for line ten (TV) based time transfers

Variation in the propagation delay for a 30 km TV (Line Ten) radio link was evaluated for a series of 30 independent measurements. Time marks from TV Channel 5 WTTG in Washington, D.C. were simultaneously measured at the Johns Hopkins University Applied Physics Laboratory and at the United States Naval Observatory against each stations' local cesium standard clocks. Differences in the stations' cesium clocks were determined by portable cesium clock transfers. Thirty independent timing determinations were made. The root mean square deviation in the propagation delay calculated from the timing determinations was 11 ns. The variations seen in the propagation delays are believed to be caused by environmental factors and by errors in the portable clock timing measurements. In correlating the propagation delay variations with local weather conditions, only a moderate dependence on air temperature and absolute humidity was found