since particulate matter (total suspended particles and particulate matter with median aerodynamic diameter less than 10 µm) is one of the important pollutants in the ambient air of tehran, the capital of iran, organic substances, inorganic substances and lead levels in tsp and pm10, correlation between tsp and pm10 concentrations, ratio among the two fractions and relation between tsp and pm10...

introduction: children may be intentionally or unintentionally exposed to any substance. substance poisoning is one of the most important emergency interventions in children that cause a great number of deaths each year. regarding the importance of this issue and recent increase in number of poisoning cases, a study with the aim of investigating cases of substance poisoning and factors involved...

objectives: according to the gateway drug theory, tobacco use is a predisposing factor for future substance abuse. this study was conducted to compare nicotine and opiate dependents to identify the differences between their personality traits and psychopathology that makes them turn to other substances after cigarette smoking. methods: a causal-comparative study was conducted. three groups were...

this study was conducted to identify emission characteristics of certain hazardous substancescontained in the plastic of used home electrical and electronic appliances keeping in view compliance with therestriction of hazardous substances (rohs) directive and to estimate the possibility of safe recyclingpractices. according to the results, the concentration of cadmium, lead, mercury and chromiu...

the current study is focused on determination of the accumulation rate of cadmium (cd) and lead (pb) in the liver and muscle tissues of the caspian kutum fish. specimens were collected randomly from twelve stations in mazandaran province, the caspian sea basin, between october 2009 and march 2010. fork length, weight and length-weight relationship of samples were measured. one-way analysis of v...

The main scientific problems of chemical bonding were solved half a century ago, but adequate philosophical understanding of chemical combination is yet to be achieved. Chemists routinely use important terms (“element,” “atom,” “molecule,” “substance”) with more than one meaning. This can lead to misunderstandings. Eliminativists claim that what seems to be a baseball breaking a window is merel...

this study was carried out to evaluate how various amounts of nanozeolite decrease the effects of aflatoxins (af) on color and oxidative stability of the broiler thigh meat. three hundred and thirty six one-day-old ross 308 male broiler chickens were divided into six groups including a control group, which received diet without af and nanozeolite, and five treatment groups that received diet wi...

in this study, the effect of some toxic organic chemicals on mogan lake has been investigatedusing the aquatox model. the unique property of the model includes the sub ecotoxicological modelwhen compared to the other water quality models. the ecosystem model aquatox, which is one of the fewgeneral ecological risk models that represents the combined environmental repercussions and effects of tox...

during the past few years, there has been an increasing recognition that internet is playing a significant role in the synthesis, the distribution and the consumption of novel psychoactive substances (nps).the aim of this study was to assess the online availability of nps in persian language websites.the google search engine was used to carry out an accurate qualitative assessment of informatio...