Thermodynamic properties of interstitial elements in the refractory metals Semiannual report, 1 Jun. - 1 Dec. 1966

Thermodynamic properties of interstitial elements in refractory metal

Free energies of formation of WC and WzC and the thermodynamic properties of carbon in solid tungsten

The activity of carbon in the two-phase regions - W + WC and W + W2C was obtained from the carbon content of iron rods equilibrated with mixtures of metal plus carbide powders. From this activity data the standard free energies of formation of WC and W2C were calculated. The temperature of the invariant reaction W2C = W + WC was fixed at 1570 + or - 5K. Using available solubility data for C in solid W, the partial molar free energy of C in the dilute solid solution was also calculated. The heat of solution of C in W, and the excess entropy for the interstitial solid solution, were computed, assuming that the carbon atoms reside in the octahedral interstices of bcc W

On the kinetics of pack aluminization

A theory of pack aluminization has been formulated by combining gaseous and solid-state diffusion rates. This theory relates the surface composition of the coating and therefore, in principle, the phase morphology and the growth rate of the coating, to pack operating parameters such as pack aluminum density, type of activator, temperature and others. Experimental data on the aluminization of unalloyed nickel in pure aluminum packs obtained to date are in good agreement with the predictions of the theory

Thermodynamic properties of interstitial elements in the refractory metals Semiannual report, 1 Dec. 1968 - 31 May 1969

Carbon activity in refractory metal

Thermodynamics and kinetics of reactions in protective coating systems

A study of the aluminization of Ni from packs containing various percentages of unalloyed Al confirmed that the surface aluminum content of specimens aluminized tends to decrease with time and consequently a simple parabolic law for the weight-gain vs. time relationship is not obeyed. The diffusivity-composition relationship in NiAl was examined, and a set of curves is presented. A numerical method for the calculation of coating dissolution rates was developed and applied to NiAl-Ni3Al type of coatings

Thermodynamic properties of interstitial elements in the refractory metals Progress report, 1 Jun. - 30 Nov. 1969

Thermodynamic properties of carbon in molybdenum and tungsten at solubility limi

Thermodynamic properties of interstitial elements in the refractory metals Semiannual report, 1 Dec. 1967 - 31 May 1968

Thermodynamic behavior of interstitial elements in Mo, W, Nb, and T

Redefining the timing and circumstances of the chicken's introduction to Europe and north-west Africa

This is the final version. Available on open access from Cambridge University Press via the DOI in this recordLittle is known about the early history of the chicken (Gallus gallus domesticus), including the timing and circumstances of its introduction into new cultural environments. To evaluate its spatio-temporal spread across Eurasia and north-west Africa, the authors radiocarbon dated 23 chicken bones from presumed early contexts. Three-quarters returned dates later than those suggested by stratigraphy, indicating the importance of direct dating. The results indicate that chickens did not arrive in Europe until the first millennium BC. Moreover, a consistent time-lag between the introduction of chickens and their consumption by humans suggests that these animals were initially regarded as exotica and only several centuries later recognised as a source of ‘food’.Arts and Humanities Research Council (AHRC)Natural Environment Research Council (NERC)Chair of Palaeoanatomy, LMU Munic

Challenging the Logics of Reformism and Humanism in Juvenile Justice Rhetoric

This article draws on contemporary policy discourse in order to advance claims about the intractable figure of the “bad” child in contemporary juvenile justice reforms in the United States (US). The article focuses in particular on the discourses of trauma and “brain science” to point to a form of neo-positivism that has arguably emerged and which challenges efforts to engage in systematic decarceration. The article also focuses on the idea of the “bad child” that persists in the commitment of some reformers to the necessity of confinement for some children. The article questions the extent to which new forms of positivism challenge our ability to leverage structural claims