the complete 3d nonlinear dynamic problem of extensible, flexible risers conveying fluid is considered. for describing the dynamics of the system, the newtonian derivation procedure is followed. the velocity field inside the pipe formulated using hydrostatic and bernoulli equations. the hydrodynamic effects of external fluids are taken into consideration through the nonlinear drag forces in var...

zno and zno: mn nanocrystals were synthesized via reverse micelle method. the structural properties of nanocrystals were investigated by xrd. the xrd results indicated that the synthesized nanocrystals had a pure wurtzite (hexagonal phase) structure. resistive gas sensors were fabricated by providing ohmic contacts on the tablet obtained from compressed nanocrystals powder and the installation ...

In this article, the effect of parameters like working gap, work piece rotational speed and material removal mechanism(injection of the SiC Abrasive slurry and Al2O3, use of diamond paste as abrasive tool) in Magnetic Abrasive Finishing process using designing of experiments on the external surface of Cylindrical work pieces of Stainless steel AISI 440C to get minimum surf...

In this article, the effect of parameters like working gap, work piece rotational speed and material removal mechanism(injection of the SiC Abrasive slurry and Al2O3, use of diamond paste as abrasive tool) in Magnetic Abrasive Finishing process using designing of experiments on the external surface of Cylindrical work pieces of Stainless steel AISI 440C to get minimum surf...

Background and objectives: Colchicum kurdicum (Bornm.) Stef. is a flowering perennial monocotyledon plant that has many important bioactive compounds especially colchicine and colchicine derivatives. In this study, the ultrasound-assisted acidic-solvent extraction method coupled with response-surface method was presented as the successful method for large scale extract...

in the present study, vibration of cylindrical laminates with different layers and angles were studied. in order to actuate and polarize in radial direction, a piezoelectric layer was located at outer surface of composite shell. laminates were assumed long enough so that plane strain state analysis in 2d can be used properly. in order to satisfy the boundary conditions, variables in terms of fo...

one of the ecient and powerful schemes to solve linear and nonlinear equationsis homotopy analysis method (ham). in this work, we obtain the approximate solution ofa system of partial dierential equations (pdes) by means of ham. for this purpose, wedevelop the concept of ham for a system of pdes as a matrix form. then, we prove theconvergence theorem and apply the proposed method to nd the a...

the present investigation entails a procedure by which the surface tension and viscosity of liquids could be redicted.to this end, capillary experiments were performed for porous media by utilizing fifteen different liquids and powders. the time of capillary rise to a certain known height of each liquid in a particular powder was recorded. two artificial neural networks (anns) were designed and...

Introduction: Fluoride counts an essential element for human health. Therefore, both low and excessive concentrations of that element in drinking water may cause health problems for the consumers. The present study aims to optimize fluoride base in drinking water using Alum response surface methodology. Methods: The present study is an analytical research which uses surface response method b...