BACKGROUND Chromium is an essential element in human nutrition. Serum concentrations of chromium are not well characterized during pregnancy or in gestational diabetes mellitus. OBJECTIVE The objective of this study was to determine whether low plasma chromium concentrations (< or =3 nmol/L) are associated with altered glucose, insulin, or lipid concentrations during pregnancy. DESIGN The s...

Chromium is one of the 25 most widespread elements in the Earth’s crust and occurs as an indelible non-volatile trace element in raw materials used in cement clinker production (clay, limestone and iron additives in particular). Chromium in raw materials mentioned above is mainly in form of trivalent chromium. Naturally occurring chromium (III) is not initially harmful, since it is chemically s...

Reduction of chromium(VI) to chromium(Ill) by thiourea between pH 3.0 and 5.5 is a key aspect of the chrominm(VI)/thiourea/polyacrylamide gel polymer system used in enhanced oil recovery processes. A method has been developed to determine chromium(Vl) concentration during the reduction of chromium(VI) to chromium(III) in this pH range. The reduction reaction is run in the presence of an acetic ...

The data on the standards for chromium requirements and the safety of various chromium compounds and doses are reviewed. The 350-fold difference between the acceptable daily intake and the calculated reference dose for humans of 70 mg per day seems without precedent with respect to other nutritional minerals. Previous claims of mutagenic effects of chromium are of questionable relevance. While ...

Theoretical analysis and Computer simulations have proven to be cost-effective and powerful tools in scientific studies of materials, particularly at nano-scale where synthesis of nano-structures, interpretation of their observed character and exploration of new structures are not always straight forward. We present here fundamental principles of techniques used today for computational simulati...

This study was undertaken to develop an assay for biologically active chromium suitable for determining the best form of chromium for human supplementation studies. The assay involved monitoring the decrease in fasting serum glucose for 1-3 hours in normal human subjects following ingestion of 100 μg of chromium. The maximum decline occurred 1-2 hours after taking the chromium. The average maxi...

Environmental pollution by arsenic (As) and hexavalent chromium (Cr(VI)) has been one of the most serious environmental problems in recent years around world. Their presence water is a result both natural anthropogenic activities, poses risks to human health due their high toxicity. Adsorption leading method used remove chromium, with biochar, carbonaceous pyrolytic product made from various ty...

aluminum alloys such as al 5083 have primary potential for lightweight structural application in automotive and aerospace industries. this paper addresses the mechanical and tribological properties and corrosion resistance of chromium nitride coatings deposited on al 5083 that can be used for development of applications of aluminum 5083 alloy. the crn coatings of 1 μm thickness were deposited b...

The essentiality and carcinogenicity of chromium depend on its chemical form. Oxidation state and solubility are particularly important in determining the biological effects of chromium compounds. For this reason, total chromium measurements are of little value in assessing its nutritional benefits or its toxicological hazards. Aqueous sodium carbonate-sodium hydroxide solutions have been succe...

Two workers exposed to trivalent chromium sulphate in a leather tannery had high concentrations of chromium in the urine. The concentration of chromium showed a workshift-related diurnal fluctuation, but it was remarkably high even after a vacation, indicating accumulation of chromium in the body. The concentrations of chromium in the workplace air, as collected on filters using standard techni...