Microbial reduction is a promising strategy for chromium remediation, but the effects of competing electron acceptors are still poorly understood. We investigated chromate (Cr(VI)) reduction in batch cultures of Shewanella oneidensis MR-1 under aerobic and denitrifying conditions and in the absence of an additional electron acceptor. Growth and Cr(VI) removal patterns suggested a cometabolic re...

a chromium electroplating bath with the ability to produce homogenous mist was used to evaluate parameters influencing hexavalent chromium (cr+6) mist sampling methods. the results of 48 cr+6mist samples collected using the u.s. national institute for occupational safety and health method 7600showed that cr+6concentration was higher: (1) for sampling by closed-face filter cassettes than for sam...

Leather processing is an important industry in China, and the discharge of chromium waste has been severely circumscribed. Though traditional processes for treating chromium waste have been widely used in tannery plants, technology adopting high efficiency and economic simultaneously is deficient. In order to develop an economic treatment for tannery waste, a mixed alkali of sodium hydroxide an...

The two common chromium oxidation states, Cr(III) and Cr(VI), differ greatly in their impacts on the environment and human health. Cr(III) in most common forms in the environment is normally not a major concern to public health because it is not very soluble and therefore poorly adsorbed by the body. In contrast, Cr(VI) in the form of chromates is usually readily soluble and, because of its oxi...

This experiment was conducted to evaluate the effect of vitamin C (L-ascorbic acid) and chromium (chromium picolinate, Cr Pic) on egg production, some egg characteristics, and digestibility of nutrients in laying hens (Hy-Line) reared under a low ambient temperature (6.2°C). Two hundred and ten laying hens (32 week-old) were divided into seven groups, 30 hens per group. The treatment groups wer...

The purpose of this study was to investigate the correlation between corrosion resistance and surface composition of an experimental Ti-20 mass% Cr casting alloy in a saline solution containing fluoride. The alloy had a greater resistance to corrosion in a fluoride-containing saline solution than did commercially pure titanium. However, with confirmed dissolution of titanium and chromium, it me...

in parts of desert regions in our country, groundwater is the only source of fresh water and due to geological formation, the concentration of hexavalent chromium in groundwater will reach beyond the allowed limits. furthermore, previous studies showed that hexavalent chromium is a cancerous substance for humans and toxic for other organisms. in this study the removal of hexavalent chromium fro...

Heavy metals have significant importance in altering the immune response. Chromium is found in the environment commonly in trivalent, Cr (III), and hexavalent, Cr (VI), forms. The reduction of Cr (VI) to Cr (III) results in the formation of reactive intermediates (ROS) that contribute to the cytotoxicity and genotoxicity. In this study mice were treated with chromium (VI) oxide (24 mg /kg body ...

The photophysics and photochemistry of [(CO)5MC(OMe)Me] (M = Cr or W) were investigated using picosecond time-resolved infrared spectroscopy (M = Cr or W), low-temperature matrix isolation techniques (M = Cr), and time-dependent density functional calculations (M = Cr or W). These studies provide unambiguous evidence for the photochemical formation of a long-lived, 18-electron metallaketene spe...

The present work was conducted for the synthesis of nano size zerovalent iron (nZVI) and hexavalent chromium (Cr(VI)) removal as a highly toxic pollutant by using this nanoparticles. Batch experiments were performed to investigate the effects of Cr(VI), nZVI concentration, pH of solution and contact time variation on the removal efficiency of Cr(VI). nZVI was synthesized by reduction of ferric ...