Ahinpunya Mitra

The crystallization behaviour of Fe 70.8 Nb 3.7 Cu 1 Al 2.7 Mn 0.7 Si 13.5 B 7.6 alloy prepared in the form of amorphous ribbons by melt-spinning technique was studied using differential scanning calorimetry and the temperature variation in resistivity. An X-ray diffaction and transmission electron microscopy study showed the formation of f -Fe and/or Fe 3 nanoparticles after the first stage of crystallization. The activation energy for this nanophase formation was 68 kcal mol m 1 . The brittleness of the alloy increased with the formation of nanoparticles after heat treatment. Superior soft magnetic properties were achieved when the material was heat treated at 790 K for 15 min. The particle size at the optimum heat treatment condition for superior soft magnetic properties was found to be 6.0 - 0.5 nm which was less compared than for the Fe-Nb-Cu-Si-B system. The observed coercivity value at the optimum heat treatment condition was found to be 0.32 A m m 1 . The presence of Al in the alloy reduced the particle size and the magnetic anisotropy energy of the system, which resulted in superior soft magnetic properties of the heat-treated materials

The best evidence in favour of a claim to knowledge warranties not the possibility of our not being wrong, so says the sceptic. Whatever grounds a putative knower has for some claim, always there exists a gap between the grounds and the claim. Anti-sceptical stands take the form of attempts either to bridge or close the gap. The Cartesian approach for bridging up the gap consists in specifying a guarantee for the subjective ground of beliefs that would secure them from sceptical attacks and elevate them to the status of knowledge. The guarantee is to be sought in the goodness of a deity, which by virtue of its sheer goodness will ensure our not being led into deception in matters of evidences for knowledge-claims, provided our epistemic endowments are used responsibly. Some not satisfied with the Cartesian tradition sought the guarantee elsewhere—in some basic self-justifying and self-evident beliefs providing foundation to our system of beliefs, which conjoined with the evidences for our claims to knowledge make such claims immune to sceptical attacks.

The projects and aims of synthetic biology raise various ethical questions, challenging some of our basic moral concepts. This chapter addresses these issues in three steps. First, we present an overview of different types of ethical issues related to synthetic biology by assigning them to three main categories: method-related, application-related, and distribution-related issues. The first category concerns the procedure and aims of synthetic biology, the second deals with certain planned applications of synthetic biology and the third with questions of distribution and access to procedures and products of this technology. Next, we address a statement often raised in the discussion about ethics of synthetic biology, namely that the ethical issues of synthetic biology have been discussed in previous debates and therefore do not need to be addressed again. We argue that past debates do not render the discussion of ethical issues superfluous because synthetic biology sets these issues in a new context and because the discussion of such issues fulfills in itself an important function, namely by stimulating thought about our relationship to technology and nature. Furthermore, given that synthetic biology’s aims go beyond those of previous technologies, we suggest that it does in fact raise novel ethical issues. Finally, we present opinions of European synthetic biologists on ethical issues in their field. At such an early stage of technological development, synthetic biologists play an important role in the assessment of their discipline, and are best placed to estimate the scientific potential of the field. In an attempt to capture the intuitions of the European synthetic biology community, we have carried out interviews, the results of which we briefly summarize in this last section. By presenting an overview of the various ethical issues and their actual and perceived importance, this chapter aims at providing a first outline for the agenda for an ethics of synthetic biology.