ahmed mahmoud
Al-Azhar University, Faculty of pharmacy, Undergraduate
MEMS Gyroscopes are used in many life applications such as drones, automobiles, and robotics. It measures the angular rate with Coriolis force. The signal for the rotation rate of the MEMS gyroscope can be produced by measuring the... more
MEMS Gyroscopes are used in many life applications such as drones, automobiles, and robotics. It measures the angular rate with Coriolis force. The signal for the rotation rate of the MEMS gyroscope can be produced by measuring the lateral motion resulting from the Coriolis force that occurs when the piezoelectric materials vibrate after being stimulated. Due to the different properties of piezoelectric materials and their impact on the sensitivity of the MEMS gyroscope with this difference, a model of the MEMS gyroscope was made using the COMSOL program. Aluminum Nitride (AlN), Zinc Oxide (ZnO) and Barium Titanate (BaTiO3) were applied to the design and the sensitivity of the rotation rate was measured using each material after calculating the frequency response of the system and clarifying the best of these materials.
Research Interests:
Genus Stachys, the largest genera of the family Lamiaceae, and its species are frequently used as herbal teas due to their essential oils. Tubers of some Stachys species are also consumed as important nutrients for humans and animals due... more
Genus Stachys, the largest genera of the family Lamiaceae, and its species are frequently used as herbal teas due to their essential oils. Tubers of some Stachys species are also consumed as important nutrients for humans and animals due to their carbohydrate contents. Three new neo-clerodane diterpene peroxides, named stachaegyptin F-H (1, 2, and 4), together with two known compounds, stachysperoxide (3) and stachaegyptin A (5), were isolated from Stachys aegyptiaca aerial parts. Their structures were determined using a combination of spectroscopic techniques, including HR-FAB-MS and extensive 1D and 2D NMR (1H, 13C NMR, DEPT, 1H-1H COSY, HMQC, HMBC and NOESY) analyses. Additionally, a biosynthetic pathway for the isolated compounds (1–5) was discussed. The chemotaxonomic significance of the isolated diterpenoids of S. aegyptiaca in comparison to the previous reported ones from other Stachys species was also studied.