chemical vapor deposition was employed to synthesize carbon nanotubes with ni-loaded mcm-41 and mcm-48 as catalysts and acetylene as precursor at 750°c. mesoporous ni mcm-41 and ni mcm-48 molecular sieves were synthesized by a hydrothermal method and were characterized by xrd and n2 adsorption isotherm. the catalytically synthesized carbon materials were characterized with raman spectroscopy, n...

in this study silver/poly vinyl alcohol (pva) and silver/poly vinyl pyrrolidone (pvp) nanocomposites were prepared via reduction of silver salt by employing dmf (n, n`- dimethyl formamide) as a reducing agent. effects of protective agents such as pva and pvp were also described here. we show that the acidic ph of pvp solution also affects the interaction between protective agents and silver nan...

background and aims: in various clinical situations, mineral trioxide aggregate (mta) may come into direct contact with blood. the aim of the present study was to evaluate the effect of exposure to blood on marginal adaptation and surface microstructure of mta. materials and methods: thirty extracted human single-rooted teeth were used in this study. standard root canal treatment was carried ou...

when grown in monolayer culture at low density and with the addition of serum, cartilage cells dedifferentiate or are overgrown by fibroblast-like cells. the aim of this study was to optimize the cultivation of chondrocytes in monolayer culture and to slow down their transformation or their overgrowth by fibroblast-like cells. the interaction between chondrocytes and cartilage-specifc matrix is...

morphological and electrophoretic analysis of the crystalline inclusions (parasporal crystals) of sporulated cultures of b. thuringiensis ssp. kumamotoensis dsm 6070 (bt 6070) was conducted via phase contrast and scanning electron microscopy and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. the activity of the spore-crystal suspensions against house fly (musca domestica) larvae wa...

the aim of this study was to compare invasive and non-invasive strains of shigella flexneri isolated from tehran by a 120 kda protein band by sds-page, electron microscopy of cell culture and congo red dye methods. methods: s. flexneri strains were isolated by standard bacterial methods from fecal specimens of children attending to the 3 children’s hospitals. phenotype analysis for screening vi...

introduction: the aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, tween 80, 2% chlorhexidine and edta, on removal of the smear layer. methods and materials: thirty-six single-rooted teeth were divided into two experimental groups ( n =12) and two positive and negative control groups of six. the cana...

introduction: smear layer (sl) is produced as a result of mechanical instrumentation of the canal(s). despite the controversies regarding its removal, the evidence-based trend has shifted towards removing and eliminating the sl. different methods have been used to remove the sl and the aim of this in vitro study was to evaluate the ability of 17% ethylenediaminetetraacetic acid (edta), 18% etid...

objective(s): trichophyton rubrum (t. rubrum) is one of the most common dermatophytes worldwide. this fungus invaded skin appendages of humans and animals. recently, resistance to antifungal drugs as well as appearance of side effects due to indication of these kinds of antibiotics has been reported. besides, using some plant extracts have been indicated in herbal medicine as an alternative tre...