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Showing 3 results for Karimpoor
Volume 6, Issue 1 (Spring & Summer 2002)
Abstract
The reason of existence of any country is a very sensitive and revived concept in the political geography. In spite of a grave theoretical background of this subject which most probably has been started from F. Ratzel, this concept, as far as the case studies are concern, is very weak and unreliable.
In order to enrich this concept in having sufficient case studies, in this research the basic root of the creation and national survival of Iran government – country is investigated. The foundation of this library research project is to respond to the following questions.
What have been the origin and essential reasons for the existence of new Iran government after five centuries and especially what is the raison for its continuity despite the different threats.
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M. Karimpoor , E. Kamrani , M. Yousefzadi, M. Nazemi ,
Volume 9, Issue 3 (Summer 2018)
Abstract
Aims: Considering the importance of health and some disadvantages of the existing synthetic compounds, the present research aimed at evaluating the antibacterial and antioxidant potential of Haliclona caerulea extracts.
Materials and Methods: In the present experimental study, organic extracts of n-hexane, diethyl ether, and methanol were prepared by the Bligh and Dyer method from the marine sponge; then, antibacterial activity was measured by disc diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC), and antioxidant activity was measured by evaluating the regenerative power and determining the total antioxidant capacity of the extracts. The data were analyzed by Duncan's new multiple range test (MRT) one-way ANOVA test. SPSS 19 and Excel 2013 software were used.
Findings: Methanol extract had the most antibacterial effect, especially against Gram positive bacterial of Bacillus subtilis with a concentration of 2.5mg/ml and Staphylococcus aureus with a concentration of 5mg/ml. Diethyl ether extracts showed the highest antioxidant activity at concentration of 5mg/ml.
Conclusion: The methanol extract of Haliclona caerulea exhibits more antibacterial properties, and the diethyl ether extract of this sponge have a higher antioxidant effect.
Volume 18, Issue 5 (9-2018)
Abstract
Piezoelectric materials, in different shapes such as rectangular plate, annular plate, circular plate and cylindrical shell, have increasing application in industries in order to create smart structures. In this article, experimental and numerical analysis of free vibration of a two-layered cylindrical panel with metal and piezoelectric layer in different boundary condition is carried out. First, a single PZT-4 layer is polarized in radial direction. Using the Piezoelectric layer and an Aluminum layer, a two-layered smart panel is prepared. Then, the first natural frequency of the hybrid panel with free boundary condition is measured experimentally in three different ways. The hybrid panel is simulated in a finite element software (Abaqus). Results show good agreement between different experimental methods, as well as, between finite element model and experimental results. The accuracy, limitations and merits of different experimental methods are discussed completely. The results show that the natural frequency can be achieved accurately by excitation of actuator layer. Finally, the influence of different boundary conditions as well as geometrical parameter such as radios, length and thickness of smart cylindrical panel are investigated using the finite element software.
