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Stretching molecules yields new understanding of electricity

Cornell University researchers recently stretched individual molecules and watched electrons flow through them, proving that single-molecule devices can be used as powerful new tools for nanoscale science experiments.

The finding, reported in the June 11 issue of the journal Science, probes the effects of strong electron interactions that can be important when shrinking electronics to their ultimate small size limit--single-molecule devices. The work resulted in the first precision tests of a phenomenon known as the underscreened Kondo effect.

Stretching single molecules allows precision studies of interacting electrons

ITHACA, N.Y. - With controlled stretching of molecules, Cornell researchers have demonstrated that single-molecule devices can serve as powerful new tools for fundamental science experiments. Their work has resulted in detailed tests of long-existing theories on how electrons interact at the nanoscale.

The work, led by professor of physics Dan Ralph, is published in the June 10 online edition of the journal Science. First author is J.J. Parks, a former graduate student in Ralph's lab.

Changing Chesapeake Bay acidity impacting oyster shell growth

Changing Chesapeake Bay acidity impacting oyster shell growth

Pop science: The physics of how bubbles burst

The physics of how bubbles burst

The physics behind bursting appears to be independent of the material of the bubble. The investigators were surprised to find that the ring effect is still seen with fairly viscous liquids like oil and even in solutions up to 5,000 times as viscous as water. Bird is anxious to study similar popping effects in more exotic materials such as molten glass, lava, and mud.

A cooler Pacific may have severely affected medieval Europe, North America

MIAMI – June 9, 2010 -- In the time before Columbus sailed the ocean blue, a cooler central Pacific Ocean has been connected with drought conditions in Europe and North America that may be responsible for famines and the disappearance of cliff dwelling people in the American West.

Amount of dust, pollen matters for precipitation in clouds, climate change, Colorado State University atmospheric scientists rev

Amount of dust, pollen matters for precipitation in clouds, climate change, Colorado State University atmospheric scientists rev

Dust, pollen counts in cloud precipitation and climate change too

Dust, pollen counts in cloud precipitation and climate change too

A lot of large particles of dust and pollen in the atmosphere may make your nose twitch, but they can lead directly to greater precipitation in clouds, Colorado State University atmospheric scientists have discovered for the first time.

Radioactive optical imaging and 'quantum dot' nano-imaging at the forefront of molecular medicine

SALT LAKE CITY—During SNM's 57th Annual Meeting, investigators presented the results of a multidisciplinary study involving the capture of radiation luminescence and radioactive-excited nanoparticles to help detect subtle signs of disease. Currently, nuclear medicine agents and imaging technology image the behavior of particles at the cellular, molecular and atomic levels, but radioactive materials also emit barely visible light that can be detected with highly sensitive optical imaging technology. This discovery could lead to new, state-of-the-art imaging techniques.

A study lays the foundations for tomographics applied to the quantum world

A study lays the foundations for tomographics applied to the quantum world

Climate change linked to major vegetation shifts worldwide

Climate change linked to major vegetation shifts worldwide

Berkeley — Vegetation around the world is on the move, and climate change is the culprit, according to a new analysis of global vegetation shifts led by a University of California, Berkeley, ecologist in collaboration with researchers from the U.S. Department of Agriculture Forest Service.

A new approach to finding and removing defects in graphene

A new approach to finding and removing defects in graphene

Scientists create artificial mini 'black hole'

Chinese researchers have successfully built an electromagnetic absorbing device for microwave frequencies. The device, made of a thin cylinder comprising 60 concentric rings of metamaterials, is capable of absorbing microwave radiation, and has been compared to an astrophysical black hole (which, in space, soaks up matter and light).

Pliocene cyprinids from Kunlun Pass Basin, northeastern Tibetan Plateau

Through studying the newly-found cyprinid fish fossils, Wang and Chang have shown that the existence of comparatively rich waters in the Kunlun Pass Basin on the southern slope of the East Kunlun Mountain (at 4769 m above sea level) and possible connections between the water systems on north and south sides of the East Kunlun Mountain during the Pliocene. They also suggest a more humid climate in the area during the Pliocene than it is today and a less amplitude of uplift (approximately 1000 m) since the Pliocene than previously proposed.

Single-particle resonances in a deformed relativistic potential

A variety of structural phenomena in exotic short-lived nuclei far from stability, especially in systems close to the particle drip lines, challenge model descriptions based on the self-consistent mean-field approximation. Because the Fermi level in a drip-line nucleus is very close to the continuum, both weakly-bound states and low-lying positive energy single-particle resonant states are essential to determine the ground state properties of such systems.

The knee at cosmic ray spectra is explained due to interactions at the sources

In the paper the authors from the Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences in Beijing proposed a new model trying to explain the knee at cosmic ray spectra. The knee kept as a puzzle in cosmic ray physics for nearly half a century. The work was inspired by the recent observation of anomalous excess of electrons and positrons in cosmic rays. The work tries to explain the knee and the electron/positron excess in a single model.