Showing 5 results for Zamani
Seyyed Masood Bagheri , Jamal Zamani, Ali Mehdipour Omrani,
Volume 6, Issue 4 (Autumn 2009 2009)
Abstract
Abstract: The purpose of this study is to produce scarf joint through explosive welding process (EXW). The scarf weld is a process in which the final bond interface is oblique. With applying the explosive welding technique, this joint can create a metallic bond between similar or dissimilar metals. In this study, chamfered end of aluminum and copper plates were joined explosively and named scarf joint, employing changes in chamfered angle at different stand-off distance and explosive loading. The geometry of scarf joint enables consideration of both flyer and base plate thickness and explosive loading and the effects on mechanical properties of interface such as bond shear strength and micro-hardness can be investigated. Mathematical models developed for the interface properties of scarf joint to make relationship between the bond shear strength and explosive loading ratio. To check the adequacy of developed models, mechanical properties of interface, such as bond shear strength, predicted and compared with actual values in explosive cladding process. The results show reasonable agreement with theoretical predictions. Consequently, mathematical model which is based on scarf joints, can predict bond shear strength of cladding metals under desired explosive loading and flyer plate thickness
F. Kashaninia, H. Sarpoolaky, A. R. Bagheri, R. Naghizadeh, M. Zamanipour,
Volume 8, Issue 4 (december 2011)
Abstract
Abstract: There have been lots of studies to control the poor hydration resistance of dolomite refractories one of the
most effective solutions has been the addition of magnesia to doloma. Using a co-clinker of magnesia-doloma as a
starting material would provide more homogeneity in the properties of the product and has been published recently.
On the other hand, addition of iron oxide to doloma has been found to increase the hydration resistance. In this paper,
the effect of iron oxide addition on hydration phase analysis and microstructure of two different magnesia- doloma
samples, one with CaO content of 25 wt% and the other one with that of 35 wt% has been investigated. Ten samples
were prepared by pressing followed by firing at 1750 ºC for 3hrs. Results showed that the hydration resistance of the
samples improved by decreasing the CaO content, because CaO is much more prone to hydration comparing to MgO.
Besides, iron oxide addition lead to the formation of iron-containing phases which increased the hydration resistance
of the samples both by capsulating the CaO and MgO grains and by promoting the liquid phase sintering.
M. Alzamani, A. Shokuhfar, E. Eghdam, S. Mastal,
Volume 10, Issue 1 (march 2013)
Abstract
Abstract:In the present research, SiO2–TiO2 nanostructure films were successfully prepared on windshields using the sol–gel technique for photocatalytic applications. To prevent the thermal diffusion of the sodium ions from the glass to TiO2 films, the SiO2 layer was pre-coated on the glass by the sol–gel method. The substrates were dipped in the sol and withdrawn with the speed of 6cm/min-1 to make a gel coating film. The coated films were dried for 2 days at 27 °C to allow slow solvent evaporation and condensation reactions due to rapid sol–gel reaction of Titania precursor. Then, the films were annealed at 100 °C for 30min and at the final temperature (500, 700 °C) for 30 min continuously. The structure and surface morphology properties, which are as a function of annealing temperature, have been studied by SEM FE-SEM and XRD. The FE-SEM surface morphology results indicate that the particle size increases from 19 to 42 nm by increasing the annealing temperature from 500 °C to 700 °C. Likewise, XRD illustrate the crystal anatase and rutile as main phases for TiO2-SiO2 films annealed at 500 °C and 700 °C respectively. This procedure resulted in transparent, crack-free SiO2–TiO2 films.
M. H. Zamani, M. Divandari, M. Tamizifar,
Volume 15, Issue 1 (March 2018)
Abstract
Lap joints of commercially pure magnesium plates to aluminium plates (Magnesium plate on the top, and Aluminium plate, grade 1100, on the bottom side) were conducted by friction stir welding using various traveling and rotation speeds of the tool to investigate the effects of the welding parameters on the joint characteristics and strength. Defect-free lap joints were obtained in the welding traveling speed range of 40-80 mm/min, and rotational speed range of 1200-1600 rpm. The shear tensile strength of Mg/Al joints increased as a result of decreasing the welding speed from 120 to 40 mm/min at constant rotation speed of 1600 rpm. Defects such as surface grooves, excessive flash, tunnels, and voids were observed if the joints prepared out of the mentioned range. The effects of the welding parameters are discussed metallographically based on observations with optical and scanning electron microscopes.
Mohammad Reza Zamani Meymian, Razieh Keshtmand,
Volume 18, Issue 4 (December 2021)
Abstract
Tin oxide (SnO2) is used as an electron transport layer (ETL) in perovskite solar cells with a planar
structure due to its good transparency and energy level alignment with the perovskite layer. The modification
interface of the electron transport layer and the perovskite absorber layer plays an important role in the efficient
charge extraction process at the interface. In this study, planar perovskite solar cells with configuration
(FTO/SnO2/mixed-cation perovskite/CuInS2/Au) were prepared to investigate the effect of UV-Ozone (UVO) treated
SnO2 as ETL on the performance of devices. ETL treatment was performed at different times (0 to 60 min). It is
shown that surface wetting was improved by UVO treating the SnO2 films prior to deposition of the perovskite layer.
The latter improves the contact between the ETL and the perovskite layer, allowing more efficient electron transport
at the interface. Contact angle, SEM, photoluminescence spectra, and the current density-voltage tests were
conducted to characterize the photovoltaic of the cells. The best PSC performance with a power conversion
efficiency of 10.96% was achieved using UVO-treated SnO2 ETL for 30 min, whereas the power conversion
efficiency of the perovskite solar cells with SnO2 ETL without UVO treatment was only 4.34%.
