Showing 3 results for Parvin
Prof. Parviz Parvin, Zohreh Ghorannevis, Mohsen Mehrabi, Pooria Taghdiri, Zahra Mortazavi, Ali Reyhani,
Volume 9, Issue 1 (International Journal of Optics and Photonics (IJOP) Vol 9, No 1, Winter-Spring 2015)
Abstract
In this paper, the magnetic properties of carbon based material, graphene is studied, which is generated by laser ablation in cryogenic media. Transmission electron microscopy (TEM) and alternating gradient force magnetometer (AGFM) are applied to investigate the graphene morphology and magnetic properties, respectively. The graphene synthesized by the laser ablation method exhibits diamagnetic behavior. However the magnetic transition from diamagnetic to paramagnetic effect is lucidly observed by functionalizing the graphene sample with silver atoms.
Ms. Fatemeh Ghasemi, Dr. Parviz Parvin, Ms. Najme Alsadat Hosseini Motlagh, Ms. Fatemeh Mirzaee, Mr. Mohammad Keraji, Mr. Ali Bavali,
Volume 9, Issue 2 (International Journal of Optics and Photonics (IJOP) Vol 9, No 2, Summer-Fall 2015)
Abstract
Simultaneous laser induced- breakdown spectroscopy (LIBS) and acoustic response techniques as well as Laser induced fluorescence (LIF) are applied to investigate the abnormal lymph tissues due to Hodgkin disease. The spectral shift in the emissive fluorescence of the cancerous tissues has been observed respect to the normal ones. Regarding LIBS, the concentrations of Ca and Na trace elements have been identified to be higher in the cancerous samples. In addition, the acoustic response of cancerous tissues has been elevated against healthy ones. The distinct differences in the spectra are taken into account for early and the rapid identification and diagnosis.
Narges Shafii Mousavi, Parviz Parvin, Maryam Ilchi-Ghazaani,
Volume 14, Issue 2 (Summer-Fall 2020)
Abstract
In this paper, an analytical model is presented to compare the monolithic end-pumped and distributed side-pumped arrangements in the master oscillator power amplifier (MOPA) of Q-switched (QSW) double-clad (DC) ytterbium (Yb)-doped fiber system. First, the time-dependent rate equations are solved numerically by the finite difference method and the output pulse characteristics are obtained. For more amplifying, the laser pulse is injected into the amplifier and the gain and saturation coefficients are obtained by using the best fitting between the outcoming data from solving rate equations and the transient amplification relation, based on the least squares method (LSM). Finally, the dependence of pump power and dopant concentration on the cavity amplifying parameters are investigated.
