due to performance grade  )pg) zonation of different parts in iran and poor properties of 60/70 penetration grade bitumens for pavement applications, suitable  polymer modifed  bitumen was  produced.  to  fulfll  this  purpose, different pmbs samples were produced using 60/70 penetration grade bitumen and  various  percentages  of vb  (20  and  25%), with  different  percentages  of  sbs calpre...

In this research work, poly (acrylonitrile-butadienestyrene)/polypropylene (ABS/PP) blends were processed by melt compounding in a twin-screw extruder. Upgrading of the thermal characteristics of the obtained materials was attempted by the incorporation of organically modified montmorillonite (OMMT), as well as, by the addition of two types of compatibilizers; polypropylene grafted with maleic ...

The fuel resistance property plays an important role in asphalts, but available standards for determining this characteristic are presently lacking. In the present work, a number of polymer modified bitumen with styrene-butadiene-styrene (SBS) polymer (4, 5, 6% SBS) and SBS/ sulfur modified bitumen with various percentages of sulfur (1.65, 3, 3.5% based on polymer content) were prepared. Each s...

Styrene has been found to be toxic to the respiratory system, and the toxicity of styrene is metabolism-dependent. CYP2E1 is suggested to be one of the cytochrome P450 enzymes responsible for the bioactivation of styrene. Our work focused on the roles of CYP2E1 and epoxide, a metabolite of styrene epoxidation, in the cytotoxicity of styrene. Styrene was found to be more toxic to h2E1 cells than...

Styrene metabolism in styrene-degrading Pseudomonas putida CA-3 cells has been shown to proceed via styrene oxide, phenylacetaldehyde, and phenylacetic acid. The initial step in styrene degradation by strain CA-3 is oxygen-dependent epoxidation of styrene to styrene oxide, which is subsequently isomerized to phenylacetaldehyde. Phenylacetaldehyde is then oxidized to phenylacetic acid. Styrene, ...

Styrene causes both liver and lung damage in non-Swiss albino, CD-1, and other strains of mice. This is considered to be due to the bioactivation of styrene to styrene oxide by cytochromes P450, principally CYP2E1 and CYP2F2. If so, one would expect CYP2E1 knockout mice to be less susceptible to styrene-induced toxicity than wild-type mice. However, previous in vitro and in vivo studies demonst...

BACKGROUND Previous studies have suggested that occupational exposure to styrene is associated with increased serum levels of the anterior pituitary hormone prolactin (PRL). AIMS To test the hypotheses that: (1) the effect of styrene exposure on PRL secretion is an acute effect, not a subchronic or chronic effect; (2) blood styrene, as a measure of absorbed dose, is a stronger predictor of se...

ALDH2 is involved in the metabolism of styrene, a widely used industrial material, but no data are available regarding the influence of this enzyme on the metabolic fate as well as toxic effects of this chemical. In this study, we recruited 329 workers occupationally exposed to styrene and 152 unexposed controls. DNA strand breaks, DNA-base oxidation in leukocytes and urinary 8-hydroxydeoxyguan...

Background: Volatile organic compounds (VOC) are considered as major environmental contaminants that have a harmful effect on human and ecosystem health, so much effort has been focused on their removal. The aim of this study was to investigate the removal efficiency of styrene by Zeolite Socony Mobil-5 (ZSM-5) after immobilization of nanoparticles of zinc oxide (ZnO) on it. Materials and Meth...

The solid complex of guest styrene included inside the channels of host c-cyclodextrin (styrene/c-CDchannel-IC) was formed in order to perform polymerization of styrene in a confined environment (c-CD channels). The experimental molar ratio of styrene to c-CD in styrene/c-CDchannel-IC was found to be 2:1, which is consistent with molecular modeling studies, utilizing Quantum Mechanics PM3 param...