Hexavalent chromium
Hexavalent chromium (chromium(VI), Cr(VI)) refers to chemical compounds that contain the element chromium in the +6 oxidation state. Virtually all chromium ore is processed via hexavalent chromium, specifically the salt sodium dichromate. Approximately 136,000 tonnes (300,000,000 lb) of hexavalent chromium was produced in 1985. Other hexavalent chromium compounds are chromium trioxide and various salts of chromate and dichromate. Hexavalent chromium is used in textile dyes, wood preservation, and as anti-corrosion and conversion coatings and a variety of niche uses. Chromium hexavalent compounds exist in several forms. Industrial uses of hexavalent chromium compounds include chromate pigments in dyes, paints, inks, and plastics; chromates added as anticorrosive agents to paints, primers, and other surface coatings; and chromic acid electroplated onto metal parts to provide a decorative or protective coating. Hexavalent chromium can be formed when performing "hot work" such as welding on stainless steel or melting chromium metal. In these situations the chromium is not originally hexavalent, but the high temperatures involved in the process result in oxidation that converts the chromium to a hexavalent state.(29 CFR OSHA General Industry 1910)
Chromium (disambiguation)
Chromium is a chemical element.
Chromium may also refer to:
- Chromium OS, the open source operating system counterpart to Google Chrome OS
See also
Chromium deficiency
Chromium deficiency is a proposed disorder that results from an insufficient dietary intake of chromium. It is an unlikely condition. Clear cases of deficiency have been observed only in hospital patients who were fed defined liquid diets intravenously for long periods of time.
Dietary guidelines
The US dietary guidelines for adequate daily chromium intake were lowered in 2001 from 50–200 µg for an adult to 30–35 µg (adult male) and to 20–25 µg (adult female). These amounts were set to be the same as the average amounts consumed by healthy individuals. Consequently, it is thought that few Americans are chromium deficient.
Chromium may fall in the same category as manganese, where it is likely that many people get too much.
Approximately 2% of ingested chromium(III) is absorbed, with the remainder being excreted in the feces. Amino acids, vitamin C and niacin may enhance the uptake of chromium from the intestinal tract. After absorption, this metal accumulates in the liver, bone, and spleen.
Yeti
The Yeti (/ˈjɛti/) or Abominable Snowman (Nepali: हिममानव himamānav, lit. "mountain man") is an ape-like cryptid taller than an average human that is said to inhabit the Himalayan region of Nepal, Bhutan and Tibet. The names Yeti and Meh-Teh are commonly used by the people indigenous to the region, and are part of their history and mythology. Stories of the Yeti first emerged as a facet of Western popular culture in the 19th century.
The scientific community generally regards the Yeti as a legend, given the lack of conclusive evidence, but it remains one of the most famous creatures of cryptozoology.
Etymology and alternate names
The word Yeti is derived from Tibetan: གཡའ་དྲེད་, Wylie: g.ya' dred, ZYPY: Yachê , a compound of the words Tibetan: གཡའ་, Wylie: g.ya', ZYPY: ya "rocky", "rocky place" and (Tibetan: དྲེད་, Wylie: dred, ZYPY: chê ) "bear". Pranavananda states that the words "ti", "te" and "teh" are derived from the spoken word 'tre' (spelled "dred"), Tibetan for bear, with the 'r' so softly pronounced as to be almost inaudible, thus making it "te" or "teh".
Yeti (comics species)
The Yeti are a number of similar fictional hidden races in the Marvel Universe.
Yeti are fur-covered humanoid beings living in the Himalaya Mountains and familiarly known as "Abominable Snowmen." There are three known varieties of Yeti.
The first, the so-called "Cold People," were highly intelligent and had made advanced scientific developments. They were transformed into normal human beings.
A far more primitive race of Yeti with human intelligence first appeared in Man-Thing vol.2, #2, but was destroyed.
An example of a third race of Yeti was encountered by Shang-Chi, and first appeared in Master of Kung Fu #124.
References
External links
Podcasts:
