1,188 research outputs found
Vienna and the Balkans: Papers from the 39th World Conference of the ICTM, Vienna, 2007, Edited by Lozanka Peycheva & Angela Rodel, Bulgarian Academy of Sciences, Sofia, 2008
Phonons in the beta-tin, Imma, and sh phases of Silicon from ab initio calculations
We present a new interpretation of measured Raman frequencies of a
high-pressure structure of Silicon which was assigned previously to the
beta-tin phase. Our results show that the beta-tin->Imma->sh phase transitions
have been already indicated in this experiment which was performed before the
discovery of the Imma phase. We have calculated phonon-dispersion curves for
the beta-tin, Imma, and sh phases of silicon using the plane-wave
pseudopotential approach to the density-functional theory and the
density-functional perturbation theory within the local density approximation.
With the new assignment, the calculated phonon frequencies display an excellent
agreement with the experimental data, and can be also used to determine
precisely the transition pressure for the Imma->beta-tin phase transition. The
sh->Imma transition is accompanied by soft modes.Comment: 4 pages, 5 figure
Antibacterial and antiparasitic effects of extracts from the aerial parts of Artemisia annua and identification of possible bioactive compounds
Antihistomonal effect of artemisinin and <em>Artemisia annua</em> extracts in experimentally infected turkeys
Antihistomonal effect of artemisinin and <em>Artemisia annua</em> extracts in experimentally infected turkeys
Quantitative assessment of bile ducts in turkeys treated with artemisinin: A model for liver toxicity?
Quantitative assessment of bile ducts in turkeys treated with artemisinin: A model for liver toxicity?
- …