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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,171 records · Page 65

Re-evaluating Sustainability Assessment: Aligning the vision and the practice

Sustainable Development is the core goal of the expanding field of Sustainability Assessment (SA). However, we find that three key areas of debate in relation to SA practice in England and Western Australia can be classified as policy controversies. Through literature review and analysis of documentary evidence we consider the problem of reductionism (breaking down complex processes to simple terms or component parts) as opposed to holism (considering systems as wholes); the issue of contested understandings of the meaning of sustainability (and of the purpose of SA); and the definition of 'inter-generational' in the context of sustainable development and how this is reflected in the timescales considered in SA. We argue that SA practice is based on particular framings of the policy controversies and that the critical role of SA in facilitating deliberation over these controversies needs to be recognised if there is to be a move towards a new deliberative sustainability discourse which can accommodate these different framings.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Applying a difference ratio method in spin-polarized scanning tunneling microscopy to determine crystalline anisotropies and antiferromagnetic spin alignment in Cr(0 0 1) c(2 $\times$ 2)

Here, we present spin-polarized scanning tunneling microscopy results for 8 micrometer thick, chromium (0 0 1)-oriented thin films deposited using molecular beam epitaxy on MgO(0 0 1) substrates, achieving a smooth, atomically-stepped staircase morphology. The c(2 × 2) surface structure of the Cr(0 0 1) surface was found via atomically-resolved scanning tunneling microscopy images and dI/dV spectroscopy. A practical method of interpreting spin-polarized scanning tunneling microscopy dI/dV images was developed and applied to the c(2 × 2) Cr(0 0 1) surface structure. A 180° spin reversal between atomic layers, characteristic of a topological, layer-wise antiferromagnetic spin structure, was quantitatively verified. In addition, the spin anisotropy directions for 3 different antiferromagnetic, atomic staircase domains occurring on the c(2 × 2) surface were quantitatively determined to coincide with the [1 0 0], [0 1 0], and [1 1 0] crystallographic axes of chromium

36 MATERIALS SCIENCE↗