normal 0 false false false en-us x-none ar-sa dear editor i read with interest the study conducted by karrari and colleagues regarding “iranian crystal a misunderstanding of the crystal-meth” published in your journal. [ 1 ] in this study, the authors have explained that the pattern of substances of abuse is varied in different parts of the world , also in iran, and the main ingredient of stree...

The size and orientation of calcium carbonate crystals influence the structure and strength of the eggshells of chickens. In this study, estimates of heritability were found to be high (0.6) for crystal size and moderate (0.3) for crystal orientation. There was a strong positive correlation (0.65) for crystal size and orientation with the thickness of the shell and, in particular, with the thic...

Sensitivities of cirrus cloud radiative forcing as well as solar albedo and infrared emittances to ice crystal size spectrum and ice crystal shape were examined using a coupled cloud-radiation model. The singleand bi-modal crystal size distribution were considered and simulated based on field measurements. Optical parameters of ice crystals shaped as hexagonal columns and random Ž . polycrystal...

nanocomposite of zro2/zno was prepared under ultrasonic irradiation by sol gel process from directly mixing zirconium and zinc gels, and the mixture was placed under ultrasonic irradiation for 2 hours then aging time the filtrated composite gel was calcinated at 500°c for 3h in furnace. the precursor sol of zirconium was prepared from an aqueous solution of zrcl4 and zinc acetate dihydrated was...

in this study, a feasible green method for the synthesis of copper oxide nanocrystalline is described by using sour cherry juice which has a significant effect on crystalline size, and morphology. the benefits of the green method, not only nanometer scale are formed but also low-cost method are obtained in a normal atmosphere which it has been used (ch3coo)2cu.h2o individually as cu sources. al...

This paper discusses about preparation of biodegradable polymer /clay nanocomposites based on organically modified montmorillonite clay; i.e. cloisite 10A and biodegradable polymer chitosan by solution mixing technique and their characterization. The nanocomposites were successfully prepared and their structures were characterized by powder x-ray diffraction (XRD), particle size analyzer (Beckm...

the composite powders of barium-magnesium ferrite were prepared using sol-gel auto-combustion and microwave methods. the crystal structure and the shape of nanocomposites have been compared. x-ray diffraction (xrd), scanning electron microscope (sem) and vibrating sample magnetometer (vsm) were used to investigate the structural, morphological and magnetic properties of nanopowder. the formatio...

nanocrystalline zno particles were prepared by a novel sonochemical route from zinc acetate and sodium hydroxide without any requirement of calcination steps at high temperature and without surfactants. variations in several parameters and their effects on the structural (crystal size and morphology) properties of nanoparticles were investigated. characterizations were carried out by x-ray diff...

Nano-sized BaTiO3 powders with particular Nb concentrations were prepared by Rotary- Hydrothermal (RH) method. Hydrothermal method was used at 180 °C for 5 hours with new Ti pressure and the teflon vessel was rotated at a speed of 160 rpm during the hydrothermal reaction. New hydrothermal method was used instead of previous solid state reaction for the system BaTiO3±Nb<sub...