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AbstractThe highest essential oil content (2.41 %) was extracted from the herb, produced at beginning of flowering stage, and the lowest amount (0.67 %) at seed ripening stage. The essential oils content of herb of plants harvested before flowering, full flowering, and at fruit set stage were: 1.59, 1.51 and 0.69 % respectively. GC and GC-MS analyses of the essential oil showed that harvest time had effect on the essential oil compositions of Thymus vulgaris.Twenty-four components were found in the essential oil extracted from the herb harvested before flowering stage. But 23, 21, 23 and 23 components in the essential oil extracted from the herbs, which were collected at beginning of flowering, full flowering, fruit set and at seed ripening stages respectively. The major component of the essential oil was thymol. The highest thymol content (57.1 %) was identified in the oil of the herb, which was collected before flowering stage and the lowest amount (48.0 %) harvested at seed ripening stage. Other essential oil constituents affected by harvest time were: y-terpinene (9.5–19.7 %), p-cymene (6.8–20.0 %), linalool (1.6–2.7 %), carvacrol (2.4–3.2 %), E-caryophyllene (1.4–2.2 %), a- terpinene (1.3–2.0 %), ß- pinene (1.3–1.8 %), and borneol (0.3–1.7 %).

AbstractThe results of hydro distillation of the aerial parts showed that different species of Saturejahad significant effect on the essential oil content. The largest amount of the essential oil (3.0%) was extracted from annual summer savory (S. hortensis) but the lowest amount (1.4%) was obtained from perennial winter savory (S. montana).The results of GC and GC-MS Analysis of the oils of different Saturejaspecies showed that species of Saturejahad also significant effect on the oil compositions. Sixteen and fourteen components were analyzed from the oil of annual and perennial savory respectively. The perennial winter savory (S. montana) accumulated more carvacrol (65.8%) than annual summer savory (S. hortensis) (38.0%).

High damping materials exhibiting a loss factor higher than 10-2 are generally considered as polymer or metallic materials. But, it will be interesting to consider ferroelectric or ferrimagnetic ceramics, in which internal friction can be due to the motion of ferroelectric or magnetic domains. High level of internal friction can be obtained in these ceramics in a given temperature range. In the case of ferroelectric ceramics, hard ferroelectrics, such as BaTiO3 or PZT, can show some relaxation peaks below the Curie temperature due the motion of domain walls and the interaction between the domain walls and the oxygen vacancies or cationic vacancies. In the case of ferrimagnetic ceramics, some anelastic manifestations due to the ferrimagnetic domain walls appear below the Curie Temperature TC. These peaks are linked to the interaction of domain walls with cation vacancies or cation interstitials or the lattice. Above the Curie temperature, a relaxation mechanism due to the exchange of cations Mn3+ and their vacancies on octahedral sites should occur.