邯郸工业吸尘器(朝阳大型工业吸尘器) (今日更新中)

WASHINGTON, Aug. 17 (Xinhua) -- Latest research shows that the Moon could be younger than previous estimates. The findings were published online Wednesday in the Nature journal.The prevailing theory of the Moon's origin is that it was created by a giant impact between a large planet-like object and the proto-Earth. The energy of this impact was sufficiently high that the Moon formed from melted material that was ejected into space. As the Moon cooled, this magma solidified into different mineral components. Analysis of lunar rock samples thought to have been derived from the original magma has given scientists a new estimate of the Moon's age.According to this theory for lunar formation, a rock type called ferroan anorthosite, or FAN, is the oldest of the Moon's crustal rocks, but scientists have had difficulty dating FAN samples. The research team used newly refined techniques to determine the age of a sample of FAN from the lunar rock that was brought back to Earth by the Apollo 16 mission in 1972.The team analyzed the isotopes of the elements lead and neodymium to place the FAN sample's age at 4.36 billion years. This figure is significantly younger than earlier estimates of the Moon's age that range as old as the age of the solar system at 4. 568 billion years. The new, younger age obtained for the oldest lunar crust is similar to ages obtained for the oldest terrestrial minerals -- zircons from western Australia -- suggesting that the oldest crusts on both Earth and Moon formed at approximately the same time, and that this time dates from shortly after the giant impact.This study is the first in which a single sample of FAN yielded consistent ages from multiple isotope dating techniques. This result strongly suggests that these ages pinpoint the time at which the sample crystallized."The extraordinarily young age of this lunar sample either means that the Moon solidified significantly later than previous estimates, or that we need to change our entire understanding of the Moon's geochemical history," Carnegie Institute of Science's geochemist and study author Richard Carlson said.

WASHINGTON, Aug. 11 (Xinhua) -- The unique fossils of an adult plesiosaur and its unborn baby may provide the first evidence that these ancient animals gave live birth like mammals, according to a new study to be published Friday in the journal Science.The 78-million-year-old, 15.4-foot-long (4.7-meter-long) adult specimen is a Polycotylus latippinus, one of the giant, carnivorous, four-flippered reptiles that lived during the Mesozoic Era.Dr. Robin O'Keefe of Marshall University in West Virginia and Dr. Luis Chiappe, Dinosaur Institute director of the Natural History Museum in Los Angeles County, have determined that it is the fossil of an embryonic marine reptile contained within the fossil of its mother.The embryonic skeleton contained within shows much of the developing body, including ribs, 20 vertebrae, shoulders, hips, and paddle bones.O'Keefe and Chiappe have also determined that plesiosaurs were unique among aquatic reptiles in giving birth to a single, large offspring, and that they may have lived in social groups and engaged in parental care.Although live birth has been documented in several other groups of Mesozoic aquatic reptiles, no previous evidence of it has been found in the important order of plesiosaurs."Scientists have long known that the bodies of plesiosaurs were not well suited to climbing onto land and laying eggs in a nest," O'Keefe said."So the lack of evidence of live birth in plesiosaurs has been puzzling. This fossil documents live birth in plesiosaurs for the first time, and so finally resolves this mystery."

GENEVA, Aug. 12 (Xinhua) -- 18 people seeking treatment at hospitals in Somalia had been confirmed cholera positive through laboratory tests, the Geneva based World Health Organization (WHO) said on Friday.The 18 positive cases were detected out of 30 stool samples collected from patients seeking treatment at hospitals for acute watery diarrhea, a symptom that could result from cholera, WHO spokesperson Tarek Jasarevic told reporters.All confirmed cases, including residents of Mogadishu district and those among internally displaced persons (IDPs), were said to be tested positive for the Vibrio cholera serotype "inaba", which had been the predominant serotype in Somalia for the past three years."These results are an alarming reminder of the critical situation in Mogadishu and other parts of Southern, Central Somalia, (which are) still experiencing drought, population displacement and conflict," Jasarevic said.WHO has reported a dramatic increase of acute watery diarrhea cases in Somalia.In June and July alone, 1,633 acute watery diarrhea cases had been registered in Banadir Hospital, Mogadishu, representing 38 percent of all reported cases in 2011, and a sharp rise comparing with the same period last year.The United Nations public health arm said the situation was related to poor sanitation and limited access to safe water in numerous informal IDP settlements and a limited capacity of existing health partners to access those settlements and provide essential health services.In addition, the high number of malnourished children due to the ongoing famine increased the susceptibility to waterborne diseases.

BEIJING, Aug. 26 (Xinhua) -- China's maritime authority on Friday once again urged U.S. oil giant ConocoPhillips to finish cleaning up oil spills in north China's Bohai Bay as soon as possible.Aug. 31 is the deadline set by the government. "There are only five days to go before the arrival of the deadline," said a statement of the State Oceanic Administration (SOA).The SOA urged ConocoPhillips China to adopt all technical measures that could be used to clean up oil spills, and to do it "with an active manner."Liu Cigui, head of the SOA, said Thursday that his administration is collecting evidence and gauging the ecological impact of the spills in preparation for possible legal action against the company.ConocoPhillips China, a subsidiary of ConocoPhillips, first reported the oil spills in June. The spills have spread to beaches in Hebei and Liaoning provinces and been blamed for losses in local tourism and aquatic farming industries.Although the company has worked to clean up the spills, pollutants have still been found in the bay, even after cleanup efforts were reported to be complete.ConocoPhillips China admitted that a total of 16 oil spill sources have been found in the bay as of Friday.

SAN FRANCISCO, Aug. 2 (Xinhua) -- Social networking giant Facebook on Tuesday announced that it has bought Push Pop Press, a digital publishing company that develops the technology to help make interactive books optimized for iPad and other Apple devices."We're thrilled to confirm that we've acquired Push Pop Press, a startup whose groundbreaking software changes the way people publish and consume digital content," Facebook said in a statement.Push Pop Press was co-founded by Mike Matas and Kimon Tsinteris, both former Apple employees, and was known for teaming up with former U.S. vice president Al Gore to create a digital version of his book "Our Choice"."Although Facebook isn't planning to start publishing digital books, the ideas and technology behind Push Pop Press will be integrated with Facebook, giving people even richer ways to share their stories," Push Pop Press said in a statement posted on its website."With millions of people publishing to Facebook each day, we think it's going to be a great home for Push Pop Press," the statement added.Financial terms of the deal were not disclosed by the two companies.

来源：资阳报