November 2012
A numerical method for second order strain gradient theory
In classical mechanics, based on the generalized Hook’s law, stress is only a function of strain. However, in the strain gradient theory, stress is not only a function of strain, but also a function of high-order gradients of strain. This relationship between stress and strain and its new boundary conditions is derived using the principle of minimum total potential energy. Meanwhile, a new stress tensor called...
November 2012
Study on ringing effect in ultrasonic transducer
This paper presents theoretical experimental and evidence of the effect of internal resonance at silicon substrate in micro fabrication ultrasonic transducer. This ringing is clearly observed in immersion transducers with 4.2 MHz and harmonics. A mathematical analytical model of the attenuation yield by ringing effective and simulation is introduced. Experimental results are further compared to simulations...
November 2012
Phytochemical screening and biological activity of the aerial parts of Elaeagnus umbellata
The methanolic crude extract of the aerial parts of Elaeagnus umbellata and its various solvent fractions was screened for the secondary metabolites and biological activity. Phytochemical analysis of the aerial parts showed the presence of bioactive secondary metabolites; alkaloids, steroids, terpenoids, saponins while flavonoids, anthraquinones, tannins, phlobatanins and glycosides were absent. The ethyl...
November 2012
Genetically tuning of lead-lag controller in order to control of fuel cell voltage
The aim of this article is to introduce, implement and control the voltage of one of the most important types of fuel cell, namely proton exchange membrane fuel cell (PEMFC) during system load variations. Fuel cell output voltage should be kept in a constant value against the load variations, and a controller should be designed for this purpose. Here, the Lead-Lag Controller is used in which its coefficients are...
November 2012
Genetically tuning of lead-lag controller in order to control of fuel cell voltage
The aim of this article is to introduce, implement and control the voltage of one of the most important types of fuel cell, namely proton exchange membrane fuel cell (PEMFC) during system load variations. Fuel cell output voltage should be kept in a constant value against the load variations, and a controller should be designed for this purpose. Here, the Lead-Lag Controller is used in which its coefficients are...
November 2012
A decision support system for supplier selection using fuzzy analytic network process (Fuzzy ANP) and artificial neural network integration
Selection of appropriate supplier(s) for success of an organization is particularly a valuable necessity, hence apart from the common criteria such as logistics, service and quality, this paper discusses most of the key decision variables which can play a critical role in case of the supplier selection. In this study, analytic network process (ANP) method is used because it considers the relationship between the...
November 2012
Kinetic studies of some hazardous metal ions in the particles of titanium potassium vanadate as a cation exchanger
Titanium potassium vanadate (TiKV) as an inorganic ion exchange material was synthesized from titanium tetrachloride, potassium chloride and sodium monovanadate with molar ratio Ti: K: V = 1: 1: 1. The kinetic behaviour of Cs+, Co2+and Cd2+ have been studied under different conditions of concentration, particle size, reaction temperatures and drying temperatures. The experimental conditions were set to favour...
November 2012
Effects of tillage, fertilization and weed control methods on corn yield in Khuzestan province
This work was carried out to evaluate the effects of seed bed preparation, fertilization and weed control (after planting) methods on growth and corn yield in Khuzestan. One field experiment was conducted as strip plot within randomized complete block design with 4 replications during 2009 and 2010. Three seed bed preparation consisted of planting in wet soil (locally named Makhar) + conventional tillage (plough + disk...
November 2012
Influence of heat and mass transfer on Phan-Thien-Tanner fluid model for blood flow through a tapered artery with a stenosis
In the present investigation, we study the influence of heat and mass transfer on blood flow through tapered artery with a stenosis. The non-Newtonian nature of blood in small arteries is analyzed mathematically by considering the blood as Phan-Thien-Tanner fluid. The representation for the blood flow is through an axially symmetrical stenosis. Symmetry of the distribution of the wall shearing stress and resistive...
November 2012
Preparation and identification of two new phthalocyanines and study of their anti-cancer activity and anti-bacterial properties
Nickel phthalocyanines chloride and nickel phthalocyanines nitrate abbreviated as NiPcCl and NiPc (NO3) respectively were synthesized and characterized. These nickel phthalocyanines are prepared by reaction of phetalic anhydride with urea, ammonium chloride and ammonium heptamolybdate, nickel related salt. Characterization of them was made by microanalyses, Fourier transform infrared spectroscopy (FT-IR) and...
November 2012
Optimizing tilt angles and orientations of solar panels for Kuala Lumpur, Malaysia
Shading of solar panels drastically reduces the solar collector’s efficiency “η” by reducing cell power “PMP”, and altering the short circuit-current “ISC”, the open-circuit voltage “VOC”, and the fill factor “FF”. Therefore, the orientation and tilt angle of solar collectors play an important role in minimizing shading and consequently in...
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