Tag Archives: crystal

In the eye of a chicken, a new state of matter comes into view

Along with eggs, soup and rubber toys, the list of the chicken’s most lasting legacies may eventually include advanced materials such as self-organizing colloids, or optics that can transmit light with the efficiency of a crystal and the flexibility of a liquid.

The unusual arrangement of cells in a chicken’s eye constitutes the first known biological occurrence of a potentially new state of matter known as “disordered hyperuniformity,” according to researchers from Princeton University and Washington University in St. Louis. Research in the past decade has shown that disordered hyperuniform materials have unique properties when it comes to transmitting and controlling light waves, the researchers report in the journal Physical Review E. (more…)

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Decoding dengue and West Nile: Researchers take steps toward control of growing public health problems

ANN ARBOR — Dengue fever and West Nile fever are mosquito-borne diseases that affect hundreds of millions of people worldwide each year, but there is no vaccine against either of the related viruses.

A team of scientists at the University of Michigan and Purdue University has discovered a key aspect both to how the viruses replicate in the cells of their host and how they manipulate the immune system as they spread. (more…)

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Taking a New Look at Carbon Nanotubes

Berkeley Researchers Develop Technique For Imaging Individual Carbon Nanotubes

Despite their almost incomprehensibly small size – a diameter about one ten-thousandth the thickness of a human hair – single-walled carbon nanotubes come in a plethora of different “species,” each with its own structure and unique combination of electronic and optical properties. Characterizing the structure and properties of an individual carbon nanotube has involved a lot of guesswork – until now.

Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have developed a technique that can be used to identify the structure of an individual carbon nanotube and characterize its electronic and optical properties in a functional device. (more…)

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Moon and Earth have common water source

Researchers used a multicollector ion microprobe to study hydrogen-deuterium ratios in lunar rock and on Earth. Their conclusion: The Moon’s water did not come from comets but was already present on Earth 4.5 billion years ago, when a giant collision sent material from Earth to form the Moon.

PROVIDENCE, R.I. [Brown University] —Water inside the Moon’s mantle came from primitive meteorites, new research finds, the same source thought to have supplied most of the water on Earth. The findings raise new questions about the process that formed the Moon. (more…)

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Portable X-Ray Source Invented at MU Could Put Medical Diagnosis and Terrorism Prevention in the Palm of the Hand

The inexpensive device could improve health in the developing world and reduce mining risks

COLUMBIA, Mo. — The hand-held scanners, or tricorders, of the Star Trek movies and television series are one step closer to reality now that a University of Missouri engineering team has invented a compact source of X-rays and other forms of radiation. The radiation source, which is the size of a stick of gum, could be used to create inexpensive and portable X-ray scanners for use by doctors, as well as to fight terrorism and aid exploration on this planet and others.

“Currently, X-ray machines are huge and require tremendous amounts of electricity,” said Scott Kovaleski, associate professor of electrical and computer engineering at MU. “In approximately three years, we could have a prototype hand-held X-ray scanner using our invention. The cell-phone-sized device could improve medical services in remote and impoverished regions and reduce health care expenses everywhere.” (more…)

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Within the Earth, Blobs of Molten Iron on the Move

New research by Yale University scientists suggests an explanation for the amount of iron in the Earth’s largest interior layer, the mantle: migrating “iron-rich blobs” generated by chemical interactions in the zone between the planet’s core and mantle.

Scientists have long known of the core’s rich iron content, but they have struggled to explain how the rocky mantle acquires iron in any abundance. The newly reported iron-enrichment process could also explain how other elements, such as platinum and hydrogen, get into the mantle, researchers said — attached to the iron. (more…)

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Nanocrystals Not Small Enough to Avoid Defects

Berkeley Lab Scientists at Advanced Light Source Show Dislocations Can Be Induced by Pressure in Ultrafine Nanocrystals

Nanocrystals as protective coatings for advanced gas turbine and jet engines are receiving a lot of attention for their many advantageous mechanical properties, including their resistance to stress. However, contrary to computer simulations, the tiny size of nanocrystals apparently does not safeguard them from defects.

In a study by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab)and collaborators from multiple institutions, nanocrystals of nickel subjected to high pressure continued to suffer dislocation-mediated plastic deformation even when the crystals were only three nanometers in size. These experimental findings, which were carried out at Berkeley Lab’s Advanced Light Source (ALS), a premier source of X-rays and ultraviolet light for scientific research, show that dislocations can form in the finest of nanocrystals when stress is applied. (more…)

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A Clock that Will Last Forever

Berkeley Lab Researchers Propose a Way to Build the First Space-Time Crystal

Imagine a clock that will keep perfect time forever, even after the heat-death of the universe. This is the “wow” factor behind a device known as a “space-time crystal,” a four-dimensional crystal that has periodic structure in time as well as space. However, there are also practical and important scientific reasons for constructing a space-time crystal. With such a 4D crystal, scientists would have a new and more effective means by which to study how complex physical properties and behaviors emerge from the collective interactions of large numbers of individual particles, the so-called many-body problem of physics. A space-time crystal could also be used to study phenomena in the quantum world, such as entanglement, in which an action on one particle impacts another particle even if the two particles are separated by vast distances.

A space-time crystal, however, has only existed as a concept in the minds of theoretical scientists with no serious idea as to how to actually build one – until now. An international team of scientists led by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) has proposed the experimental design of a space-time crystal based on an electric-field ion trap and the Coulomb repulsion of particles that carry the same electrical charge. (more…)

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