fluorescence chemical sensors for the highly sensitive and selective determination of pb2+ , hg2+, co2+ and fe3+ ions in aqueous solutions are described. the ion sensing system was prepared by incorporating lipophilic ligand (l) as a neutral ion-selective fluoroionophore in the plasticized pvc membrane containing sodium tetraphenylborate or potasium tetrakis (p-chlorophenyl) borate as a liphoph...

abstract objectives gradual increase length and complexity of utterance (gilcu) therapy method is a form of operant conditioning. this type of treatment is very precise and controlled that is done in 54 steps in 3 speech situations consisted of monologue, reading and conversation. this study aimed to examine the effects of gilcu treatment method on reduction of speech dysfluency of school-age...

in this research the focus of the researcher is on the influence of american myths that have long been held and offered by the american culture and ideologies. sam shepard is conceived to be one of the greatest playwrights of the contemporary american theater. in his works he depicts broken characters who are struggling to keep up with the national expectations but are ceaselessly borne back to...

colonialism is an important factor in cultural production and many of cultural constructs all over the world. english and english language teaching are at the center of the contemporary world. postcolonial literature, the genre achebe exercised, is a kind of historical text which has become central to different debates and criticisms. in this thesis, different elements related to the colonial...

wireless sensor networks (wsns) are one of the most interesting consequences of innovations in different areas of technology including wireless and mobile communications, networking, and sensor design. these networks are considered as a class of wireless networks which are constructed by a set of sensors. a large number of applications have been proposed for wsns. besides having numerous applic...

the history of plant’s used for mankind is as old as the start of humankind. initially, people used plants for their nutritional proposes but after the discovery of medicinal properties, this natural ?ora became a useful source of disease cure and health improvement across various human communities. berberis vulgaris is one of the medicinal plants used in iranian traditional medicine. berberis ...

?it is of utmost priority for an experienced teacher to train the mind of the students, and enable them to think critically and correctly. the most important question here is that how to develop such a crucial ability? this study examines a new way to the development of critical thinking utilizing critical discourse analytical tools. to attain this goal, two classes of senior english la...

the space now known as complete erdos space ec was introduced by paul erdos in 1940 as the closed subspace of the hilbert space ?2 consisting of all vectors such that every coordinate is in the convergent sequence {0} ? { 1 n : n ? n}. in a solution to a problem posed by lex g. oversteegen we present simple and useful topological characterizations of ec. as an application we determine the ...

abstract: country’s fiber optic network, as one of the most important communication infrastructures, is of high importance; therefore, ensuring security of the network and its data is essential. no remarkable research has been done on assessing security of the country’s fiber optic network. besides, according to an official statistics released by ertebatat zirsakht company, unwanted disconnec...

in this study, the effects of oleothermal modification on physical and mechanical peroperties of fir wood (abeis sp.) blocks were examined. at first, some blocks of fir wood with 5 × 20 × 120 cm dimensions were prepared. the blocks were treated in soybean oil. the effects of 3 factors such as treatments temperature (180and 200 °c), holding time (12 and 15 h) and initial moisture content of wood...