Interoduction: Gasteroenteritis is one of the problems worth consideration all over the world. It is one of the important causes of mortality, especially in children < 5 years of age, in developing countries including Iran. The aim of this descriptive study was to determine the demographic conditions influencing the presence of causative bacteria and protozoa, followed by antibiograms of isolat...

in this thesis, a new optically active poly(amide-imide) (pai) was synthesized by the indirect polycondensation reaction of the l-phenylalanine based diacid chloride and 4,4?-diaminodiphenylether in the presence of triethylamine in n-methyl-2-pyrrolidone. the formation of pai was confirmed by ftir, 1h nmr and elemental analysis. in next step, the surface of titanium dioxide (tio2) nanoparticles...

cohesion is an indispensable linguistic feature in discourse analysis. lexicald such a differe cohesion and conjunction in particular as two crucial elements to textual cohesion and comprehension has been the focus of a wide range of studies up to now. yet the relationship between the open register and cohesive devices has not been thoroughly investigated in discourse studies. this study concen...

the main objective in sampling is to select a sample from a population in order to estimate some unknown population parameter, usually a total or a mean of some interesting variable. a simple way to take a sample of size n is to let all the possible samples have the same probability of being selected. this is called simple random sampling and then all units have the same probability of being ch...

Background and purpose: Polycyclic aromatic hydrocarbons (PAHS) are environmental pollutants that are caused by human activity and considered as carcinogenic and mutagenic compounds. Anthracene is a hazardous substance causing serious health problems. There are many bacteria with the ability to remove this pollutant. The aim of of this study was isolation of some bacteria from Tajan river e...

        Background & Aim: Listeria monocytogenes has potentiality to cause serious invasive disease in humans and in more than 40 animal species. L. monocytogenes is transmitted from soft cheese, milk, raw meat and sausages to human. The present study was undertaken to find the frequency of L. monocytogenes in poultry, domestic animals, sausage, cheese, milk, and also to determine ctpA(copper t...

Introduction: Increasing resistance to antimicrobial agents is typically one of the main problems of health care. Control the dispersion of bacteria in different environments is a challenge in this section that to the overcome of them is essential for health and economic. In this study, nano-silver antibacterial activity was studied against Gram-positive bacteria Staphylococcus aureus and Pseud...

‏‎the main purpose of this research was to:1.develop a coking model for thermal cracking of naphtha.2.study coke inhibition methods using different coke inhibitors.developing a coking model in naphtha cracking reactors requires a suitable model of the thermal cracking reactor based on a reliable kinetic model.to obtain reliable results all these models shall be solved simultaneously.for this pu...

abstract nowadaysphotovoltaic solar cells (pvs) areacknowledged the fastest growing energy technology in the word, however, they only account for only fraction of current global renewable energy capacity. it isrecognized that this incomplete market penetration has been largely a result of the technology’sexcessive cost. so researchers are trying to find innovative, economic way with theaim of ...