California experienced centuries-long droughts in the past 20,000 years that coincided with the thawing of ice caps in the Arctic, according to a new study by UC Davis doctoral student Jessica Oster and geology professor Isabel Montañez.
The finding, which comes from analyzing stalagmites from Moaning Cavern in the central Sierra Nevada, was published online Nov. 5 in the journal Earth and Planetary Science Letters.
Iowa State scientist develops lab machine to study glacial sliding related to rising sea levelsAMES, Iowa - Neal Iverson opened his laboratory's walk-in freezer and said the one-of-a-kind machine inside could help scientists understand how glaciers slide across their beds. And that could help researchers predict how glaciers will react to climate change and contribute to rising sea levels.
New data show that the balance between the airborne and the absorbed fraction of CO2 has stayed approximately constant since 1850, despite emissions of CO2 having risen from about 2 billion tons a year in 1850 to 35 billion tons a year now.
This suggests that terrestrial ecosystems and the oceans have a much greater capacity to absorb CO2 than had been previously expected.
Aerosols, very small particles suspended in the air, play an important role in the global climate balance and in regulating climate change. They are one of the greatest sources of uncertainty in climate change models. ESA's GlobAerosol project has been making the most of European satellite capabilities to monitor them.
Researchers at the McCormick School of Engineering and Applied Science at Northwestern University have developed, characterized, and modeled a new kind of probe used in atomic force microscopy (AFM), which images, measures, and manipulates matter at the nanoscale.
Using diamond, researchers made a much more durable probe than the commercially available silicon nitride probes, which are typically used in AFM to gather information from a material, but can wear down after several uses.
The catalytic processes that facilitate the production of many chemicals and fuels could become much more environmentally friendly thanks to a breakthrough achieved by researchers from Lehigh and Rice Universities.
In an article published Nov. 8 by the journal Nature Chemistry, the researchers report a novel electron microscopy imaging study of a tungstated zirconia solid acid catalyst. Based on new information obtained from these images, the researchers were able to design a preparation procedure that increased the activity of the catalyst by more than 100 times.
Good news for heterogeneous catalysis and the hydrogen economy: computers can now be used to make accurate predictions of the reactions of (hydrogen) molecules with surfaces. An international team of researchers, headed by Leiden theoretical chemist Geert-Jan Kroes, published on this subject this week in the journal Science.
Hydrogen on copper
November 9, 2009 -- The practice of sterilizing medical tools and devices helped revolutionize health care in the 19th century because it dramatically reduced infections associated with surgery. Through the years, numerous ways of sterilization techniques have been developed, but the old mainstay remains a 130-year-old device called an autoclave, which is something like a pressure steamer. The advantage of the autoclave is that the unsterile tools can be packed into sealed containers and then processed, staying sealed and sterile after they are removed.
November 9, 2009 -- Eric Shaqfeh studies blood at Stanford University, using computer models that simulate how the fluid and the cells it contains move around. On November 11 at a meeting of the scientific society AVS, he will present his latest unpublished findings from two studies. One shows how components in blood line up to prepare for healing; the other demonstrates the best shape to use for man-made nanoparticles that target cancers -- a surfboard.
November 9, 2009 -- Dana Filoti of the University of New Hampshire will present thin films of silver and copper she has developed that can kill bacteria and may one day help to cut down on hospital infections. The antimicrobial properties of silver and copper have been known for centuries -- last year, the U.S. Environmental Protection Agency officially registered copper alloys, allowing them to be marketed with the label "kills 99.9% of bacteria within two hours." Copper ions are known to penetrate bacteria and disrupt molecular pathways important for their survival.
In an international first, scientists from the Institute of Quantum Optics and Quantum Information (IQOQI) produced a Bose-Einstein condensate of the alkaline-earth element strontium, thus narrowly winning an international competition between many first-rate scientific groups. Choosing the isotope 84Sr, which has received little attention so far, proved to be the right choice for the breakthrough. It can now be regarded as an ideal candidate for future experiments with atomic two-electron systems.
Large blooms of tiny marine plants called phytoplankton are flourishing in areas of open water left exposed by the recent and rapid melting of ice shelves and glaciers around the Antarctic Peninsula. This remarkable colonisation is having a beneficial impact on climate change. As the blooms die back phytoplankton sinks to the sea-bed where it can store carbon for thousands or millions of years.
Two independent teams have, for the first time, created Bose-Einstein condensates of strontium atoms. The ability to cool strontium to very low temperatures and control its motion could lead to increasingly precise clocks and may advance our progress toward quantum computers and novel experiments in ultracold chemistry. The new Bose-Einstein condensate is reported in two papers in Physical Review Letters and highlighted with a Viewpoint in the November 9 issue of Physics (http://physics.aps.org.)
With an average of four mini-earthquakes per day, Southern California's San Jacinto fault constantly adjusts to make it a less likely candidate for a major earthquake than its quiet neighbor to the east, the Southern San Andreas fault, according to an article in the journal Nature Geoscience.
"Those minor to moderate events along the San Jacinto fault relieve some of the stress built by the constantly moving tectonic plates," said Shimon Wdowinski, research associate professor at the University of Miami's Rosenstiel School of Marine and Atmospheric Science.
Good news for heterogeneous catalysis and the hydrogen economy: computers can now be used to make accurate predictions of the reactions of (hydrogen) molecules with surfaces. An international team of researchers, headed by Leiden theoretical chemist Geert-Jan Kroes, published on this subject this week in the journal Science.
Hydrogen on copper