in the process of vermicomposting, the earthworms eisenia fetida have been exposed to various metals with different concentrations to study the effects on worms’ bioaccumulation. the study was carried within 14 days of exposure. five different chemical compounds in various concentrations were added as mixture solutions to the experimental containers. metals concentrations were measured in earth...

In this research, dipeptide (his-β-alanine) and porphyrin derivatives were choosen for comparing chelating ability of toxic metals such as Al3+, Cu2+, Hg2+ and Pb2+ in vitro. The reason for choosing these two compounds is that both of them are naturally present in biological systems and comparison of chelating ability of these two compounds has not yet been done. Synthesis and comparison of kin...

Metals and metal compounds have been used for many years in the manufacture of plastic products. The metallic compounds added to plastics although encapsulated in polymer matrix are usually not chemically bound to polymer molecules and consequently can gradually be released to environment over the service life of a plastic made object. Similarly, when disposing of plastic waste either by incine...

In this research, dipeptide (his-β-alanine) and porphyrin derivatives were choosen for comparing chelating ability of toxic metals such as Al3+, Cu2+, Hg2+ and Pb2+ in vitro. The reason for choosing these two compounds is that both of them are naturally present in biological systems and comparison of chelating ability of these two compounds has not yet been done. Synthesis and comparison of kin...

This is the second part of a study that evaluates the influence of nonpoint sources on the sediment quality of five adjacent streams within the metropolitan Kansas City area, central United States. Physical, chemical, and toxicity data (Hyalella azteca 28-day whole-sediment toxicity test) for 29 samples collected in 2003 were used for this evaluation, and the potential causes for the toxic effe...

In recent years, heavy metal pollution has become one of the most serious environmental problems. The pollution of environment with toxic heavy metals is spreading throughout the world along with industrial progress. Presence of heavy metals even in traces is toxic and detrimental to all living organisms. Moreover it cannot be degraded in to simpler harmless compounds like other pollutants incl...

The ability of calcium aluminate cement (CAC) to encapsulate toxic metals (Pb, Zn and Cu) was assessed under two curing conditions. Changes in the consistency and in the setting time were found upon the addition of the nitrates of the target metals. Both Pb and Cu caused a delay in CAC hydration, while Zn accelerated the stiffening of the mortar. Compressive strengths of the metal-doped mortars...

introduction: nowadays, advancements in industries, technology and human welfare level have lead to accumulation of solid wastes and have endangered environmental health. incorrect waste management intensifies this problem. recycling and composting (transformation of organic waste to humus) are the most important ways in waste management. health and safety of the compost is an important issue b...