Applying laboratory thermal desorption data in an interstellar context: sublimation of methanol thin films

Methods by which experimental measurements of thermal desorption can be applied in astrophysical environments have been developed, using the sublimation of solid methanol as an example. The temperature programmed desorption of methanol from graphitic, amorphous silica and polycrystalline gold substrates was compared, with the kinetic parameters of desorption extracted by either a leading edge analysis or by fitting using a stochastic integration method. At low coverages, the desorption shows a substrate-dependent fractional order. However, at higher coverages methanol desorption is zeroth order with kinetic parameters independent of substrate. Using a kinetic model based on the stochastic integration analyses, desorption under astrophysically relevant conditions can be simulated. We find that the chemical and morphological nature of the substrate has relatively little impact on the desorption temperature of solid methanol, and that the substrate independent zeroth-order kinetics can provide a satisfactory model for desorption in astrophysical environments. Uncertainties in the heating rate and the distribution of grain sizes will have the largest influence on the range of desorption temperature. These conclusions are likely to be generally applicable to all species in dust grain ice mantles

Authenticity and the 'Authentic City'

In this paper, I argue that the benefits that smart cities purport to provide cohere poorly with a number of our shared phenomenological intuitions about the relationships(s) between authentic experience and technologised society. While many of these intuitions are, strictly speaking, pseudo-problems, they deserve our attention. These issues will only grow more pressing as our ‘dumb cities’, already so opaque to experience, give way to hyper-technologised ‘smart cities’. However, it is possible to design our way out of these pseudo-problems. Assuming we accept my argument that the distinction between authenticity and the device paradigm is premised upon a certain kind of category error, there is no categorical or definitional reason why it is not possible for urbanised, technologised spaces to feel authentic, whether by virtue of their aesthetic properties, or because they facilitate ‘authentic’ behaviour. Indeed, I argue that ‘inauthenticity’ is an aesthetic rather than an ontological category (much like ‘ugliness’, or ‘boring-ness’), with feelings of inauthenticity serving as evidence of a basic failure of design. Redressing these failures of design requires that we adopt a novel approach to the design and use of technical objects. Consequently, in the concluding analysis of the chapter I outline how the feeling of authenticity can be invoked in the smart city and, consequently, how these failures of design can be avoided.<br/

The rise of inconspicuous consumption

Ever since Veblen and Simmel, luxury has been synonymous with conspicuous consumption. In this conceptual paper we demonstrate the rise of inconspicuous consumption via a wide-ranging synthesis of the literature. We attribute this rise to the signalling ability of traditional luxury goods being diluted, a preference for not standing out as ostentatious during times of economic hardship, and an increased desire for sophistication and subtlety in design in order to further distinguish oneself for a narrow group of peers. We decouple the constructs of luxury and conspicuousness, which allows us to reconceptualise the signalling quality of brands and the construct of luxury. This also has implications for understanding consumer behaviour practices such as counterfeiting and suggests that consumption trends in emerging markets may take a different path from the past

Soft x-ray resist characterization: Studies with a laser plasma x-ray source

Little work has been performed to characterize the exposure sensitivity, contrast, and tone of candidate resists for photon energies between 100--300 eV, the range in which projection soft x-ray lithography will be developed. We report here the characterization of near-edge x-ray absorption fine structure (NEXAFS) spectra, exposure sensitivity, contrast, and post-exposure processing of selected polysilane resists at photon energies close to the Si L{sub 2,3} absorption edge (100 eV). We find absorption resonance features in the NEXAFS spectra which we assign to excitation into Si--Si and Si--C {sigma}* orbitals. Using monochromatized XUV exposures on the Si--Si {sigma}* resonance at 105 eV, followed by solvent dissolution development, we have measured the exposure sensitivity curves of these resists. We find sensitivities in the range of 600--3000 mJ/cm{sup 2} and contrasts in the range from 0.5--1.4, depending on the polysilane side chain. We have also performed exposure sensitivity measurements at 92 eV, below the edge. Sensitivity decreases slightly compared to 105 eV exposures and the saturation depth and contrast both increase, as expected. We find also that exposing resist films to oxygen after XUV exposure, but before development increases the sensitivity markedly. 7 figs