Synthetic fuel Ruhr Area. In 1937, the four central Germany lignite coal plants at Böhlen, Leuna, Magdeburg/Rothensee, and Zeitz, along with the Ruhr Area bituminous coal plant at Scholven/Buer, had produced of fuel. Four new hydrogenation plants () were subsequently erected at Bottrop-Welheim (which used "Bituminous coal tar pitch"), Gelsenkirchen (Nordstern), Pölitz, and, at 200,000 tons/yr Wesseling. Nordstern and Pölitz/Stettin used bituminous coal, as did the new Blechhammer plants. Heydebreck synthesized food oil, which was tested on concentration camp prisoners. The Geilenberg Special Staff was using 350,000 mostly foreign forced laborers to reconstruct the bombed synthetic oil plants, and, in an emergency
Interlanguage fossilization advance gradually until it becomes equivalent, or nearly equivalent, to the target language. However, during the second language learning process, an interlanguage may reach one or more temporary restricting phases when its development appears to be detained. A permanent cessation of progress toward the target language has been referred to as fossilization. This linguistic phenomenon, interlanguage fossilization, can occur despite all reasonable attempts at learning. Fossilization includes those items, rules, and sub-systems that second language learners tend to retain in their interlanguage, that is, all those aspects of interlanguage that become entrenched and permanent, and that the majority of second