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Latest Chalcogens Stories

2009-11-12 11:14:47

A new study from the University of Warwick has discovered taking too much of the essential mineral selenium in your diet can increase your cholesterol by almost 10%. Selenium is a trace essential mineral with anti-oxidant properties. The body naturally absorbs selenium from foods such as vegetables, meat and seafood. However, when the balance is altered and the body absorbs too much selenium, such as through taking selenium supplements, it can have adverse affects.  A team led by Dr...

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2009-10-30 10:05:00

Even low concentrations of oxygen can have profound effects on ocean chemistry Scientists widely accept that around 2.4 billion years ago, the Earth's atmosphere underwent a dramatic change when oxygen levels rose sharply. Called the "Great Oxidation Event" (GOE), the oxygen spike marks an important milestone in Earth's history, the transformation from an oxygen-poor atmosphere to an oxygen-rich one, paving the way for complex life to develop. Two questions that remain unresolved in studies...

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2009-10-28 08:11:33

Fossil land snail shells found in ancient soils on the subtropical eastern Canary Islands show that the Spanish archipelago off the northwest coast of Africa has become progressively drier over the past 50,000 years. Isotopic measurements performed on fossil land snail shells resulted in oxygen isotope ratios that suggest the relative humidity on the islands was higher 50,000 years ago, then experienced a long-term decrease to the time of maximum global cooling and glaciation about 15,000 to...

2009-10-05 02:01:00

HOUSTON, Oct. 5 /PRNewswire/ -- PAC, a leading global provider of advanced analytical instruments for laboratories and online process applications, announces the introduction of the ANTEK MultiTek(TM) testing system for the fast, accurate detection of sulfur, nitrogen, and halides. Industries include BioFuels, Chemicals, Food & Beverage, Manufacturing and Assembly, Medical, Pharmaceutical, Environmental, and many more. "MultiTek(TM) is the only instrument on the market that combines...

2009-09-10 15:01:07

Danish-led scientists say an analysis of rock found only in the world's oldest oceans has shed light on how large animals obtained a foothold on Earth. The team led by University of Copenhagen Professor Robert Frei said it has, for the first time, plotted the rise and fall of oxygen levels in the Earth's atmosphere that occurred during the last 3.8 billion years. By analyzing the isotopes of chromium in iron-rich sediments formed in the ancient oceans, the team found a rise in atmospheric...

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2009-09-10 05:25:00

Analysis of a rock type found only in the world's oldest oceans has shed new light on how large animals first got a foothold on the Earth. A scientific team led by Professor Robert Frei at the University of Copenhagen in Denmark, and including scientists from Newcastle University, UK, and universities in Uruguay and Southern Denmark, have for the first time managed to plot the rise and fall of oxygen levels in the Earth's atmosphere over the last 3.8 billion years. By analyzing the isotopes...

2009-09-01 04:00:00

HOUSTON, Sept. 1 /PRNewswire/ -- The International Fuel Quality Center (IFQC) has updated its ranking of the top 100 countries based on sulfur limits in on-road diesel -- Sweden, Germany and Japan, remained first, second and third, respectively. "This year's ranking shows the tremendous movement being made globally toward zero sulfur fuels, as the top 44 countries all have sulfur limits of 50 ppm or less," said Liisa Kiuru, executive director, IFQC. "We can expect to see sulfur reduction...

2009-06-30 13:20:48

A U.S. biologist says the accumulation of metals in plants may be a strategy to protect the plants from predators such as prairie dogs. Postdoctoral researcher John Freeman of Colorado State University and colleagues said certain plant species growing on soils with high metal content, such as arsenic, copper, selenium or lead, accumulate large quantities of metals in their leaves and stems. The purpose of that hyperaccumulation isn't fully known, but Freeman said it might increase a plant's...

2009-06-25 15:36:38

-Higher selenium levels in the blood may worsen prostate cancer in some men who already have the disease, according to a study by researchers at Dana-Farber Cancer Institute the University of California, San Francisco.A higher risk of more-aggressive prostate cancer was seen in men with a certain genetic variant found in about 75 percent of the prostate cancer patients in the study. In those subjects, having a high level of selenium in the blood was associated with a two-fold greater risk of...

2009-06-23 15:35:00

Prairie dogs may seem like harmless little creatures, but they can inflict serious injury on plants simply by snacking on them. Plants cannot flee from their furry predators, so how do they avoid becoming a prairie dog's lunch?Dr. John Freeman and colleagues explore the role of metal hyperaccumulation in plant defense in the June 2009 issue of the American Journal of Botany. Certain plants species growing on soils with high metal content (such as arsenic, copper, selenium, and lead)...


Word of the Day
monteith
  • A large punch-bowl of the eighteenth century, usually of silver and with a movable rim, and decorated with flutings and a scalloped edge. It was also used for cooling and carrying wine-glasses.
  • A kind of cotton handkerchief having white spots on a colored ground, the spots being produced by a chemical which discharges the color.
This word is possibly named after Monteith (Monteigh), 'an eccentric 17th-century Scotsman who wore a cloak scalloped at the hem.'
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