in this thesis protic and aprotic ammonium-based ionic liquids were synthesized and their surface tensions were measured in the range of 298-373k. the protics are alkyl ammonium-based ils with the carboxylate (formate, acetate, propionate) anion and aprotics are quaternary ammonium-based ils with bis(trifluoromethylsulfonyl)imide anion. capillary rise method was used for surface tension measure...

saluk mount is selected for devonian biostratigraphy. this area located at southwest of bojnurd. in this study three sections are selected and two sections, chahar-borj and tabar sections with a thickness of 650 m, which consist mainly of calcareous sediments was studied in detailed but third section, qelli section, with a thickness of about 450m which consist mainly of sandstone and evaporates...

implicit and unobserved errors and vulnerabilities issues usually arise in cryptographic protocols and especially in authentication protocols. this may enable an attacker to make serious damages to the desired system, such as having the access to or changing secret documents, interfering in bank transactions, having access to users’ accounts, or may be having the control all over the syste...

in this thesis, a structured hierarchical methodology based on petri nets is used to introduce a task model for a soccer goalkeeper robot. in real or robot soccer, goalkeeper is an important element which has a key role and challenging features in the game. goalkeeper aims at defending goal from scoring goals by opponent team, actually to prevent the goal from the opponent player’s attacks. thi...

the rationale behind the present study is that particular learning strategies produce more effective results when applied together. the present study tried to investigate the efficiency of the semantic-context strategy alone with a technique called, keyword method. to clarify the point, the current study seeked to find answer to the following question: are the keyword and semantic-context metho...

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...

abstract since heubners (1985) pioneering study, there have been many studies on (mis) use/ non-use of articles by l2 learners from article-less and article languages. the present study investigated how persian l2 learners of english produce and interpret english definite descriptions and demonstrative descriptions. it was assumed that definite and demonstrative descriptions share the same cen...

a one dimensional dynamic model for a riser reactor in a fluidized bed catalytic cracking unit (fccu) for gasoil feed has been developed in two distinct conditions, one for industrial fccu and another for fccu using various frequencies of microwave energy spaced at the height of the riser reactor (fccu-mw). in addition, in order to increase the accuracy of component and bulk diffusion, instanta...

abstract in the present research solution of chalcopyrite in sulfuric acid in hydrometallurgy method using electrochemistry with cyclic voltammetry technique has been investigated. the value of maximum reduction peak current of copper ions represents the measure of solubility. in this research different parameters temperature, potential, potential exert time, chalcopyrite concentration, sulfur...

in reality, most structures involved in geotechnical engineering are three dimensional in nature, and although in many, plane strain or axisymmetric approximations are reasonable, there are some, for which 3-d treatment is required. the quantity of data, and the size of the various vectors and matrices involved in such analysis, increase dramatically. this has sever implications for computer r...