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...

this study sought to examine the effect of cooperative game on iranian students achievements in english alphabet learning. cooperative games are games, in which players or teams work together towards a common goal without defeating someone. the methodology used in this study was experimental. the population of the study was 60 female students from the grade one in secondary school in tabriz, ir...

abstract: in the paper of black and scholes (1973) a closed form solution for the price of a european option is derived . as extension to the black and scholes model with constant volatility, option pricing model with time varying volatility have been suggested within the frame work of generalized autoregressive conditional heteroskedasticity (garch) . these processes can explain a number of em...

the significance of the study of deixis was then mentioned. the purpose of the present study from the outset was to provide a comprehensive overview of all kinds of deixis in persian, describing and defining each in true while considering them structurally and semantically. chapter two consisted of two main parts. a review of the english studies in this respect, besides presenting persian liter...

1.0 overview it seems that grammar plays a crucial role in the area of second and foreign language learning and widely has been acknowledged in grammar research. in other words, teaching grammar is an issue which has attracted much attention to itself, and a lot of teachers argue about the existence of grammar in language teaching and learning. this issue will remind us a famous sentence f...

abstract amino acids are building blocks of proteins, and play a vital role in living beings existence and their functionality. the interaction of these compounds with metal ions is of great importance to biochemists, and chemists, because their functions can be utilized as a model in understanding enzymes mechanism for transport of metal ions to tissues. among twenty essential amino acids w...

the effect of the presence of perforations on he stresses of a plate is a problem which is of great interest in structural design and in the mathemattical theory of elasticity. among the many hole patterns that are likely to require consideration is the ring of equally spaced circular holes. the present worke investigates stress & strain analysis of a thin isotropic circular plate containing a ...

to discuss my point, i have collected quite a number of articles, anthologies, and books about "wuthering heights" applying various ideas and theories to this fantastic story. hence, i have come to believe that gadamer and jauss are rightful when they claim that "the individaul human mind is the center and origin of all meaning," 3 that reading literature is a reader-oriented activity, that it ...

increasing academic and professional language demands around the world are not a deniable fact. the purpose of this study was to investigate english language needs and communication needs of the chemistry students at master and ph.d. levels at the iranian universities. in this research, different methods were used including un-structured interview, structured interview, and two sets of question...

چکیده در بخش اول این پروژه دو روش میکرواستخخرا به نامهای میکرواسخخرا امولسیونی با کمک اموا فراصتتتو 1 و میکرواستتتخخرا مای – مای با کمک هوا 2 ، به عنوان دو روش میکرواستتتخخرا بدون حلال پخشکننده 3 ، برای اسخخرا برخی هیتدروکربتنهای آروماتیتک حلقوی 4 از نمونتههای آبتی بهکار گرفخه و پارامخرهای موثری همچون نوع حلال اسختتتتخرا کننده، حجم حلال اسخخرا کننده، میزان نمک، زمان تابش اموا فراصتو ، تددا...