Tuesday - February 6, 2007

Ancient Warriors and the Origin of Chinese Purple

Samples of a pigment called Chinese purple were obtained from this kneeling archer, one of 8,000 terra cotta warriors discovered in 1974. (Click on image for larger version.)

by Brad Plummer

In 1974, while sinking irrigation wells in the Chinese province of Shaanxi, a group of farmers made an astonishing archeological discovery. Buried beneath their feet stood a contingent of 8,000 life-sized terra cotta warriors and their horses, facing east, ready for battle. The figures, later found to be more than 2,000 years old, were accompanied by weapons, real chariots, and objects of jade and bone. It was later determined that this army was built to protect the tomb of the first emperor of the Qin dynasty, Shi Huang Di.

Today many puzzles still surround these statues. One of the most intriguing of these mysteries is the origin of a synthetic purple pigment, often called "Chinese purple" or "Han purple," that their ancient creators used to adorn the soldiers and their accessories. Now, using advanced x-ray techniques, researchers at the Stanford Synchrotron Radiation Laboratory (SSRL) have unraveled a major piece of this puzzle.

Until the 19th century, most pigments were made from naturally occurring minerals or organic dyes. One well-known exception is "Egyptian blue," which is chemically very similar to the Chinese purple. Because the Egyptian and Chinese pigments are so chemically close in composition, some have proposed that the technology to create Chinese purple was in fact derived from the Egyptians. If that were so, Chinese purple would represent one of the earliest known cases of cross-cultural technology transfer, dating to a period before the Silk Road opened China to the west, even before the invention of paper or the compass.  Read more...

Distracted Driving:
A Recipe for Disaster

by Tim Miller

A recent study by the National Highway Traffic Safety Administration and the Virginia Tech Transportation Institute concluded that driver distraction is the leading cause of traffic accidents. Video cameras and sensors monitored 100 automobiles in the Washington, DC metro area. Data collection lasted a year, encompassing two million miles and 42,000 hours of driving. The study recorded a total of 82 crashes, 761 near crashes, and 8,295 critical incidents.

The researchers concluded that "nearly 80 percent of crashes and 65 percent of near crashes involved some form of driver inattention within three seconds before the event." The tabulated data (above) show that reaching for a moving object or looking at an external object increase the risk by factors of nine and three, respectively. Talking or listening on a cell phone, however, does not appear to carry a significant risk, though dialing does increase the hazard. The one behavior that actually reduced the risk was having a passenger in the adjacent seat.

Here are three suggestions to reduce your risk of a crash from distracted driving:

Secure everything that could be a distraction.

Do not drive when you are tired.

Do not perform tasks that require multiple glances in a short period of time, such as operating a PDA.

DOE Press Release:
$24.3 Billion Request
for FY 2008 Budget

Secretary Bodman presents President Bush's FY08 budget request for DOE.

U.S. Secretary of Energy Samuel W. Bodman has announced President Bush's $24.3 billion budget request for the Department of Energy (DOE) for Fiscal Year (FY) 2008. This request supports continued scientific discovery and the development of alternative energy sources that are vital to America's energy and economic security. Funding priorities include investments to address growing demand for affordable, clean and reliable energy; further scientific discovery; continue the legacy waste environmental cleanup; and strengthen and maintain the nation's nuclear weapons stockpile while promoting global non-proliferation.

"Under President Bush's leadership, this budget builds on our commitment to strengthen our nation's energy security by diversifying our energy resources and reducing our reliance on foreign sources of energy. In addition, this budget will help us expand our nation's scientific know-how, protect generations from the dangers of our Cold War legacy, and safely and reliably maintain our nation's nuclear weapons stockpile," Secretary Bodman said. Read more...

Safety Seconds

by John Cornuelle

In yesterday's edition, I asked if you could identify the ignored safety practice that would have prevented one of the most famous personalities in the modern world from dying. Princess Diana never fastened her seat belt, whether in an automobile or an airplane. Do you think she ever thought about the consequences for her two young sons when she did that?

Events (see all | submit)

• February 6: (12:30 p.m.) Experimental Seminar: Radiative Penguin Decays b -> s gamma and New Physics
• February 7: (1:30 p.m.) AIS Lothar Struder: Imaging X-ray Detectors

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• North entrance to Building 41 parking lot closed
• Building 40 construction
• Alpine Gate & PEP Ring Road closed
• Gates 17 & 30 open 24-7
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• New Publication: ESH Manual, Chapter 43, Industrial Wastewater

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• Local Sailor Missing
• Lunar New Year Luncheon - Feb. 16

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• Satellite Prepares to go Super-Cold BBC News
• Physicists Plan Search for the Known Unknowns Nature

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