in the present work, a simple and sensitive method was developed for determination of morphine and heroin using gold nanoparticles as resonance rayleigh scattering (rrs) and colorimetric technique’s probe. synthesized gold nanoparticles by sodium citrate reduction method have a negative charge layer on their surfaces because of self-assembled citrate anions on their surface. binding of morphin...

abstract sensitive and precise voltammetric methods for the determination of trace amounts of furaldehydes, mainly as furfural (f) and 5-hydroxymethyl-2-furaldehyde (hmf), in waste waters and other matrices is described. determination of total furaldehyde at < ?g g-1 levels in alkaline buffered aqueous media was individually investigated. by the use of ordinary swv and adsorptive square wave ...

in the area of automotive engineering there is a tendency to more electrification of power train. in this work control of an induction machine for the application of electric vehicle is investigated. through the changing operating point of the machine, adapting the rotor magnetization current seems to be useful to increase the machines efficiency. in the literature there are many approaches wh...

in the first part of this thesis we explored wetting and its dynamics for small droplets. first, we showed how a simple feature of water droplets on a surface, i.e. laplace pressure, can be exploited to build a micropump. we investigated capillary pumping in microchannels both experimentally and numerically. putting two droplets of different sizes at the in/outlet of a microchannel, will ge...

abstract in aggregate, active forms of reactive silica with mineral names are sometimes associated with sand and gravel in concrete mixture. alkali hydroxides originated from alkalis in the cement or other resources form an alkaline silica gel with this reactive silica which becomes swallowed and expanded during time causing damage to concrete. there have been growing researches on alkaline r...

abstract venlafaxine, 1–[2–(dimethylamino)–1–(4–methoxyphenyl) ethyl]cyclohexanol hydrochloride is a novel non-tricyclic antidepressant. venlafaxine is a second generation antidepressant drug, has a neuropharmacologic profile distinct from that of existing antidepressants including tricyclic compounds, selective serotonin reuptake inhibitors and monoamine oxidase inhibitors. venlafaxine impart...

this study was conducted to investigate the impact of podcasts as a learning and teaching tool on iranian efl learners’ motivation for listening as well as on their listening comprehension ability. the study also investigated the learners’ perception towards listening to podcasts and examined whether the learners were likely to accept podcasts. out of fifty-five intermediate learners studying e...

abstract in first part of this project, the use of a new and biguanid-like catalyst supported on silica as a recyclable catalyst provides a new route for the synthesis of a variety of arylalkylidene rhodanine derivatives through knoevenagle reaction in at present of solvent at room temperature. rhodanine derivatives and especially arylalkylidene rhodanines have proven to be attractive compound...

abstract this research has been carried out with the purpose of investigating the conditions and related elements of the employment of the educational sciences graduates of hamedan province universities in 1382-1387 academic years. it has been a descriptive research of a correlation kind, and the population number has been 1180 grduates of payam- e noor universites in asad – abaad, kaboudaraha...

while performance-based language assessment has led to an increased authenticity and content validity in the practice of writing assessment, the reliability of ratings has become a major issue. research findings have shown different reactions by native english speaker (nes) and non-native english speaker (nns) teachers to students’ writings. the focus of this study is on investigating whether i...