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...

foreign policy takes root from complicated matters. however, this issue may be more truth about armenia. although the new government of armenia is less than 20 years, people of this territory are the first ones who officially accepted christianity. in very past times, these people were a part of great emperors like iran, rome, and byzantium.armenia is regarded as a nation with a privileged hist...

Background and purpose: Aquatic ecosystems are important sources of food for human which are sometimes highlycontaminated. It is important to determine their levels of contaminations, so, in this study, theconcentrations of lead, cadmium and nickel was investigated in the gills and musclesof Barbusxanthopterus captured from Dez River, Iran. Materials and methods: Thirty samples of Barbusxantho...

in this thesis, barium ferrite nano particles were prepared by sol-gel method. their structural and magnetic properties of samples have been investigated using thermo gravimetric analysis (tg-dta), x-ray powder diffractometer (xrd), fourier transform infrared (ftir), scanning electron microscopy (sem), field emission scanning electron microscopy (fesem), ac susceptometer, vibrating sample magne...

Background and purpose: Heavy metal pollution is among the most serious environmental issues that is caused directly or indirectly through human activities or natural sources. Alagol wetland is one of the most important ecosystems in Iran which is affected by numerous agricultural and industrial development programs. Materials and methods: A descriptive cross-sectional study was performed in s...

the central purpose of this study was to conduct a case study about the role of self monitoring in teacher’s use of motivational strategies. furthermore it focused on how these strategies affected students’ motivational behavior. although many studies have been done to investigate teachers’ motivational strategies use (cheng & d?rnyei, 2007; d?rnyei & csizer, 1998; green, 2001, guilloteaux & d?...

now-a-days graphic design plays a major role in influencing culture, society, business, and customers, in such a way that one could look upon every individual as a potential customer. graphic designers seek to identify customers needs and find an intelligent solution for them. correct identification and understanding of those needs is the first step towards achieving ones goals. marketing knowh...

 Background and Aim: Sewage of non-metallic and mineral industrials such as tile and ceramic contain a large amount of heavy metals (e.g. Zn, Cr, Cd, Pb) and minerals which can cause problems such as contaminating underground water and polluting the environment. Thus, the present study was done to evaluate heavy metals concentration in the effluent and sludge of the tile factory in Birjand.  ...