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 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...

in this thesis our aim is to construct vector field in r3 for which the corresponding one-dimensional maps have certain discontinuities. two kinds of vector fields are considered, the first the lorenz vector field, and the second originally introced here. the latter have chaotic behavior and motivate a class of one-parameter families of maps which have positive lyapunov exponents for an open in...

a novel silver (ag) nanocomposite electrode was proposed that fabricated from metal nanostructures and ionic liquids. the combined application of unique properties of nanomaterials and ionic liquids in the design of this ag nanocomposite results in electrodes with interesting advantages compared to the conventional metal disk electrode. in the first part of this thesis, the elecrocatalytic eff...

چکیده با توسعه شهر نشینی و دخل و تصرف غیر مجاز در حریم رودخانه ها خسارات زیادی به رودخانه و محیط زیست اطراف آن وارده می شود. در حال حاضر بر اساس آئین نامه اصلاح شده بستر و حریم رودخانه ها، حریم کمی رودخانه که بلافاصله پس از بستر قرار می گیرد از 1 تا20 متر از منتهی الیه طرفین بستر رودخانه تعیین، که مقدار دقیق آن در هر بازه از رودخانه مشخص نیست. در کشورهای دیگر روشهای متفاوتی من جمله: درصد ریسک...

abstract ion selective electrodes (ises) are electrochemical sensors that respond selectivity to the activity of ionic species. an ion-selective electrode is an electrochemical device that uses a thin selective membrane or film as the recognition element, and is an electrochemical half-cell equivalent to other half-cells of the zeroth (inert metal in a redox electrolyte). in common methods o...

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...

one of the applications of nanotechnology is use of carbon nanotubes for the targeted delivery of drug molecules. to demonstrate the physical and chemical properties of biomolecules and identify new material of drug properties, the interaction of carbon nanotubes (cnts) with biomolecules is a subject of many investigations. cnts is a synthetic compound with extraordinary mechanical, thermal, el...

abstract this study is carried out to determine the chemical composition in the three vegetative stages of the haloxylon sp., degradation parameters, with adding naoh and ca(oh2 ). for this purpose, in may and october and january 2010 enough some haloxylon sp. of the ammary area was prepared. crude protein and ash percentage are decrease, neutral detergent fiber percentage with pragress stage ...

this study attempted to explore if teaching english collocations through two different modes of awareness-raising and input flooding has any possible differential effect on immediate retention as well as retention in a delayed assessment. it also compared the possible differential effect of teaching english collocations implicitly and explicitly on actively using the items in writing. m...