Synthetic fuel the fuel, and the fuel is less dense than conventional jet fuel allowing aircraft to fly further on the same load of fuel. The "cleanness" of these FT synthetic fuels is further demonstrated by the fact that they are sufficiently non-toxic and environmentally benign as to be considered biodegradable. This owes primarily to the near-absence of sulfur and extremely low level of aromatics present in the fuel. One concern commonly raised about the development of synthetic fuels plants is sustainability. Fundamentally, transitioning from oil to coal or natural gas for transportation fuels production is a transition from one inherently depletable
Interlanguage fossilization particularly regarding achievement motivation, especially considering that fossilization can be considered the most distinctive characteristic of adult SLA. The text of this article is taken with permission from "The Role of Achievement Motivation on the Interlanguage Fossilization of Middle-Aged English-as-a-Second-Language Learners" by Dr. Zoran Vujisić (2007). Interlanguage fossilization Interlanguage fossilization is a phenomenon of second language acquisition (SLA) in which second language learners develop and retain a linguistic system, or interlanguage, that is self-contained and different from both the learner's first language and the target language. This linguistic system has been variously called interlanguage, approximative system, idiosyncratic dialects, or transitional