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June 5, 2011, 8:54 PM CT

Upping the anti

Upping the anti
This is an artist's image of the ALPHA trap which captured and stored antihydrogen atoms.

Credit: Chukman So

Science fiction is fast approaching science fact as scientists are progressing rapidly toward "bottling" antimatter. In a paper published online today by the journal Nature Physics, the ALPHA experiment at CERN, including key Canadian contributors, reports that it has succeeded in storing antimatter atoms for over 16 minutes. While carrying around bottled antimatter like in the movie Angels and Demons remains fundamentally far-fetched, storing antimatter for long periods of time opens up new vistas for researchers struggling to understand this elusive substance. ALPHA managed to store twice the antihydrogen (the antimatter partner to normal hydrogen) 5,000 times longer than the prior best, setting the stage, for example, to test whether antihydrogen and normal hydrogen fall the same way due to gravity.

Main author Makoto Fujiwara, TRIUMF research scientist, University of Calgary adjunct professor, and spokesperson of the Canadian part of the ALPHA team said, "We know we have confined antihydrogen atoms for at least for 1,000 seconds. That's almost as long as one period in hockey! This is potentially a game changer in antimatter research."

Antimatter remains one of the biggest mysteries of science. At the Big Bang, matter and antimatter should have been produced equally, but since they destroy each other upon contact, eventually nothing should have remained but pure energy (light). However, all observations suggest that only the antimatter has vanished. To figure out what happened to "the lost half of the universe," researchers are eager to determine if, as predicted, the laws of physics are the same for both matter and antimatter. ALPHA uses an analogue of a very well-known system in physics, the hydrogen atom (one electron orbiting one proton), and testing whether its antimatter twin, antihydrogen (an antielectron orbiting an antiproton), behaves the same. But to study something one must hold onto it long enough.........

Posted by: Sarah      Read more         Source


May 29, 2011, 2:39 PM CT

Seeing hidden building blocks of life

Seeing hidden building blocks of life
A diamond surrounded by air, and a glass of water. Both contain carbon and oxygen. If they are embedded inside another object, without access for a chemical probe, it is a difficult task to distinguish between even simple chemical bonds. A new synchrotron X-ray technique has made this now possible.

Credit: Simo Huotari (University of Helsinki)

Researchers from Finland and France have developed a new synchrotron X-ray technique that may revolutionize the chemical analysis of rare materials like meteoric rock samples or fossils. The results have been published on 29 May 2011 in Nature Materials as an advance online publication.

Life, as we know it, is based on the chemistry of carbon and oxygen. The three-dimensional distribution of their abundance and chemical bonds has been difficult to study up to now in samples where these elements were embedded deep inside other materials. Examples are tiny inclusions of possible water or other chemicals inside martian rock samples, fossils buried inside a lava rock, or minerals and chemical compounds within meteorites.

X-ray tomography, which is widely used in medicine and material science, is sensitive to the shape and texture of a given sample but cannot reveal chemical states at the macroscopic scale. For instance graphite and diamond both consist of pure carbon, but they differ in the chemical bond between the carbon atoms. This is why their properties are so radically different. Imaging the variations in.

atomic bonding has been surprisingly difficult, and techniques for imaging of chemical bonds are highly desirable in a number of fields like engineering and research in physics, chemistry, biology, and geology.........

Posted by: William      Read more         Source


March 20, 2011, 10:08 PM CT

Rapid, high-definition chemistry

Rapid, high-definition chemistry
IRENI-generated images (right) are 100 times less pixelated than in those from conventional infrared imaging (left). Using multiple beams from a synchrotron provided made the difference, providing enough light to obtain a detailed image of the sample. With this technique, the quality of the chemical images is now similar to that of optical microscopy.

Credit: Carol Hirshmugl/Michael Naase

With intensity a million times brighter than sunlight, a new synchrotron-based imaging technique offers high-resolution pictures of the molecular composition of tissues with unprecedented speed and quality. Carol Hirschmugl, a physicist at the University of Wisconsin-Milwaukee (UWM), led a team of scientists from UWM, the University of Illinois at Urbana-Champaign and University of Illinois at Chicago (UIC) to demonstrate these new capabilities.

Hirschmugl and UWM scientist Michael Nasse have built a facility called "Infrared Environmental Imaging (IRENI)," to perform the technique at the Synchrotron Radiation Center (SRC) at UW-Madison. The new technique employs multiple beams of synchrotron light to illuminate a state-of-the-art camera, instead of just one beam.

IRENI cuts the amount of time needed to image a sample from hours to minutes, while quadrupling the range of the sample size and producing high-resolution images of samples that do not have to be tagged or stained as they would for imaging with an optical microscope.

"Since IRENI reveals the molecular composition of a tissue sample, you can choose to look at the distribution of functional groups, such as proteins, carbohydrates and lipids," says Hirschmugl, "so you concurrently get detailed structure and chemistry".........

Posted by: Sarah      Read more         Source


March 18, 2011, 10:08 PM CT

An icy gaze into the Big Bang

An icy gaze into the Big Bang
The research group led by Rudolf Grimm reports on a first experimental step into the strongly interacting regime of an ultracold Fermi-Fermi mixture.

Credit: Harald Ritsch

Researchers of the Institute for Quantum Optics and Quantum Information (IQOQI) in Innsbruck, Austria, have reached a milestone in the exploration of quantum gas mixtures. In an international first, the research group led by Rudolf Grimm and Florian Schreck has succeeded in producing controlled strong interactions between two fermionic elements - lithium-6 and potassium-40. This model system not only promises to provide new insights into solid-state physics but also shows intriguing analogies to the primordial substance right after the Big Bang.

As per theory, the whole universe consisted of quark-gluon plasma in the first split seconds after the Big Bang. On the earth this cosmic primordial "soup" can be observed in big particle accelerators when, for example, the nuclei of lead atoms are accelerated to nearly the speed of light and smashed into each other, which results in particle showers that are investigated with detectors. Now the group of quantum physicists led by Prof. Rudolf Grimm and PhD Florian Schreck from the Institute for Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences together with Italian and Australian scientists has for the first time achieved strong controlled interactions between clouds of lithium-6 and potassium-40 atoms. Hence, they have established a model system that behaves in a similar way as the quark-gluon plasma, whose energy scale has a twenty times higher order of magnitude.........

Posted by: Sarah      Read more         Source


March 8, 2011, 7:45 AM CT

Hunt for green catalysts

Hunt for green catalysts
L. Keith Woo's hunt for green catalysts has led him to experiment with iron porphyrins. Here he's holding a model of an iron porphyrin compound in his Iowa State University research lab.

Credit: Photo by Bob Elbert/Iowa State University

L. Keith Woo is searching for cleaner, greener chemical reactions.

Woo, an Iowa State University professor of chemistry and an associate of the U.S. Department of Energy's Ames Laboratory, has studied catalysts and the chemical reactions they affect for more than 25 years. And these days, his focus is on green catalysis.

That, he said, is the search for catalysts that lead to more efficient chemical reactions. That could mean they promote reactions at lower pressures and temperatures. Or it could mean they promote reactions that create less waste. Or it could mean finding safer, cleaner alternatives to toxic or hazardous conditions, such as using water in place of organic solvents.

"We're trying to design, discover and optimize materials that will produce chemical reactions in a way that the energy barrier is lowered," Woo said. "We're doing fundamental, basic catalytic work".

And much of that work is inspired by biology.

In one project, Woo and his research group are studying how iron porphyrins (the heme in the hemoglobin of red blood cells) can be used for various catalytic applications. Iron porphyrins are the active sites in a variety of the enzymes that create reactions and processes within a cell. Most of the iron porphyrin reactions involve oxidation and electron transfer reactions.........

Posted by: Sarah      Read more         Source


February 22, 2011, 7:54 AM CT

The Year of the Higgs?

The Year of the Higgs?
This February, scientists will renew their search for one of the universe's most elusive mysteries, the Higgs boson--a hypothetical particle that if found would give an insight into why particles have certain mass.

The search will take place at the Large Hadron Collider (LHC) at CERN, the world's largest particle accelerator at the European Organization for Nuclear Research in Geneva, Switzerland.

The Higgs boson is the only remaining Standard Model particle that has not been observed in particle physics experiments. But using two separate and complimentary experiments, the A Toroidal LHC Apparatus (ATLAS) and Compact Muon Solenoid (CMS), researchers hope to prove its existence.

Both ATLAS and CMS are particle physics detectors. They are located on opposite sides of the 27-kilometer (17-mile) LHC ring circling the countryside on the outskirts of Geneva, buried deep below ground.

The LHC has been offline during a winter break, which temporarily halted the experiments.

"The research program over this past year was essentially to commission the accelerator and the experiments to make sure that they work and they are giving us sensible results," said physicist Aaron Dominguez of the University of Nebraska and the US CMS experiment, whose work is supported by the National Science Foundation.........

Posted by: Sarah      Read more         Source


February 8, 2011, 6:48 AM CT

Bound Neutrons Pave Way to Free Ones

Bound Neutrons Pave Way to Free Ones
Some experiments seem to show that the building blocks of protons and neutrons inside a nucleus are somehow different from that of free ones. Other experiments show they behave differently when they pair up: they move faster and frequently overlap.
A study of bound protons and neutrons conducted at the Department of Energy's Thomas Jefferson National Accelerator Facility has allowed scientists, for the first time, to extract information through experimentation about the internal structure of free neutrons, without the assistance of a theoretical model. The result was reported in the Feb. 4 issue of Physical Review Letters.

The major hurdle for researchers who study the internal structure of the neutron is that most neutrons are bound up inside the nucleus of atoms to protons. In nature, a free neutron lasts for only a few minutes, while in the nucleus, neutrons are always encumbered by the ubiquitous proton.

To tease out a description of a free neutron, a group of researchers compared data collected at Jefferson Lab and the SLAC National Accelerator Laboratory that detail how bound protons and neutrons in the nucleus of the atom display two very different effects. Both protons and neutrons are referred to as nucleons.

"Both effects are due to the nucleons behaving like they are not free," says Doug Higinbotham, a Jefferson Lab staff scientist.

Nucleons appear to differ when they are tightly bound in heavier nuclei versus when they are loosely bound in light nuclei. In the first effect, experiments have shown that nucleons tightly bound in a heavy nucleus pair up more often than those loosely bound in a light nucleus.........

Posted by: Sarah      Read more         Source


February 7, 2011, 3:48 PM CT

Neutron analysis reveals superconductivity link

Neutron analysis reveals superconductivity link
Neutron scattering analysis of two families of iron-based materials suggests that the magnetic interactions thought responsible for high-temperature superconductivity may lie "two doors down": The key magnetic exchange pairings occur in a next-nearest-neighbor ordering of atoms, rather than adjacent atoms.

Scientists at the Department of Energy's Oak Ridge National Laboratory and the University of Tennessee, using the Spallation Neutron Source's ARCS Wide Angular Range Chopper Spectrometer, performed spin-wave studies of magnetically ordered iron chalcogenides. They based their conclusions on comparisons with prior spin-wave data on magnetically ordered pnictides, another class of iron-based superconductors.

"As we analyze the spectra, we find that even though the nearest neighbor exchange couplings between chalcogenide and pnictide atoms are different, the next nearest neighbor exchange couplings are closely similar," said Pengcheng Dai, who has a joint appointment with ORNL's Neutron Sciences Directorate and the University of Tennessee.

Dai referred to theories that have suggested second-nearest-neighbor couplings could be responsible for the widely acclaimed but poorly understood properties of high-temperature superconductors.

"There are theories suggesting that it's the second nearest neighbor that drives the superconductivity," he said. "Our discovery of similar next-nearest-neighbor couplings in these two iron-based systems suggests that superconductivity shares a common magnetic origin."........

Posted by: Sarah      Read more         Source


February 1, 2011, 8:00 AM CT

Quantum-mechanical implementation of 'shell game'

Quantum-mechanical implementation of 'shell game'
The photon shell game architecture: Two superconducting phase qubits (squares in the center of the image) are connected to three microwave resonators (three meander lines).

Credit: Erik Lucero, Matteo Mariantoni, Dario Mariantoni

Inspired by the popular confidence trick known as "shell game," scientists at UC Santa Barbara have demonstrated the ability to hide and shuffle "quantum-mechanical peas" �� microwave single photons �� under and between three microwave resonators, or "quantized shells".

In a paper reported in the Jan. 30 issue of the journal Nature Physics, UCSB scientists show the first demonstration of the coherent control of a multi-resonator architecture. This topic has been a holy grail among physicists studying photons at the quantum-mechanical level for more than a decade.

The UCSB scientists are Matteo Mariantoni, postdoctoral fellow in the Department of Physics; Haohua Wang, postdoctoral fellow in physics; John Martinis, professor of physics; and Andrew Cleland, professor of physics.

As per the paper, the "shell man," the researcher, makes use of two superconducting quantum bits (qubits) to move the photons �� particles of light �� between the resonators. The qubits �� the quantum-mechanical equivalent of the classical bits used in a common PC �� are studied at UCSB for the development of a quantum super computer. They constitute one of the key elements for playing the photon shell game.

"This is an important milestone toward the realization of a large-scale quantum register," said Mariantoni. "It opens up an entirely new dimension in the realm of on-chip microwave photonics and quantum-optics in general".........

Posted by: Sarah      Read more         Source


January 28, 2011, 7:16 PM CT

Chemistry Now Video Series

Chemistry Now Video Series
In celebration of the International Year of Chemistry, the National Science Foundation (NSF) and NBC Learn, the educational arm of NBC News, have teamed up to launch "Chemistry Now," a weekly online video series that uncovers and explains the science of common physical objects in our world and the changes they undergo every day. The series also looks at the lives and work of researchers on the frontiers of 21st century chemistry.

"Chemistry Now" consists of 32 learning packages that aim to break down the chemistry behind things such as cheeseburgers and chocolate or soap and plastics. A new topic will be explored each week starting in January and running through May. The series will then resume in the fall of 2011 to keep pace with the academic school year.

Made particularly for students and teachers to explore chemistry in and beyond the classroom, the online videos are matched with lesson plans from the National Science Teachers Association (NSTA) and are available cost-free on NBC Learn and NSF's Science360 websites and on the NSTA blog.

Weekly content includes original video stories that illustrate real-world applications of chemistry; current events and archival news stories correlation to chemistry; original source documents and images from the Chemical Heritage Foundation; articles from the archives and current publications of Scientific American; and content-coordinated lesson plans for middle and high school students, produced by national curriculum specialists at NSTA.........

Posted by: Sarah      Read more         Source


January 26, 2011, 6:55 AM CT

A new look at the atom

A new look at the atom
Graduate student Vincent Lonij (left), associate professor of physics Alex Cronin, research assistant Will Holmgren and undergraduate student Catherine Klauss perform maintenance on a chamber used to beam atoms through a grating to measure a tiny force that helps physicists better understand the structure of atoms.

Credit: Norma Jean Gargasz/UANews

Measuring the attractive forces between atoms and surfaces with unprecedented precision, University of Arizona physicists have produced data that could refine our understanding of the structure of atoms and improve nanotechnology. The discovery has been reported in the journal Physical Review Letters

Van der Waals forces are fundamental for chemistry, biology and physics. However, they are among the weakest known chemical interactions, so they are notoriously hard to study. This force is so weak that it is hard to notice in everyday life. But delve into the world of micro-machines and nano-robots, and you will feel the force � everywhere.

"If you make your components small enough, eventually this van-der-Waals potential starts to become the dominant interaction," said Vincent Lonij, a graduate student in the UA department of physics who led the research as part of his doctoral thesis.

"If you make tiny, tiny gears for a nano-robot, for example, those gears just stick together and grind to a halt. We want to better understand how this force works".

To study the van-der-Waals force, Lonij and his co-workers Will Holmgren, Cathy Klauss and associate professor of physics Alex Cronin designed a sophisticated experimental setup that can measure the interactions between single atoms and a surface. The physicists take advantage of quantum mechanics, which states that atoms can be studied and described both as particles and as waves.........

Posted by: Sarah      Read more         Source


January 11, 2011, 6:55 AM CT

How do you make lithium melt in the cold?

How do you make lithium melt in the cold?
ophisticated tools allow researchers to subject the basic elements of matter to conditions drastic enough to modify their behavior. By doing this, they can expand our understanding of matter. A research team including three Carnegie researchers was able to demonstrate surprising properties of the element lithium under intense pressure and low temperatures. Their results were published Jan. 9 on the Nature Physics website.

Lithium is the first metal in the periodic table and is the least dense solid element at room temperature. It is most usually known for its use in batteries for consumer electronics, such as cell phones and laptop computers. And, with only three electrons per atom, lithium should behave like a model, simple metal.

However, this research has shown that under pressure ranging between about 395,000 atmospheres (40 GPa) and about 592,000 atmospheres (60 GPa), lithium behaves in a manner that's anything but simple. Not only does it become a liquid at room temperature, but it then refuses to freeze until the temperature reaches a chilly -115o F. At pressures above about 592,000 atmospheres (60 GPa), when lithium does eventually solidify, it is into a range of highly complex, crystalline states. The highest pressure reached in the study was about 1.3 million atmospheres (130 GPa).........

Posted by: Sarah      Read more         Source


January 6, 2011, 6:09 PM CT

Sulphur important in the formation of gold mines

Sulphur important in the formation of gold mines
Collaborating with an international research team, an economic geologist from The University of Western Ontario has discovered how gold-rich magma is produced, unveiling an all-important step in the formation of gold mines.

The findings were reported in the recent issue of Nature Geoscience

Robert Linnen, the Robert Hodder Chair in Economic Geology in Western's Department of Earth Sciences conducts research near Kirkland Lake, Ontario and says the results of the study could lead to a breakthrough in choosing geographic targets for gold exploration and making exploration more successful.

Noble metals, like gold, are transported by magma from deep within the mantle (below the surface) of the Earth to the shallow crust (the surface), where they form deposits. Through a series of experiments, Linnen and colleagues from the University of Hannover (Gera number of), the University of Potsdam (Gera number of) and Laurentian University observed that gold-rich magma can be generated in mantle also containing high amounts of sulphur.

"Sulphur wasn't recognized as being that important, but we found it actually enhances gold solubility and solubility is a very important step in forming a gold deposit," explains Linnen. "In some cases, we were detecting eight times the amount of gold if sulphur was also present".........

Posted by: Sarah      Read more         Source


December 16, 2010, 8:05 AM CT

Periodic table about to make an historic change

Periodic table about to make an historic change
For the first time in history, a change will be made to the atomic weights of some elements listed on the Periodic table of the chemical elements posted on walls of chemistry classrooms and on the inside covers of chemistry textbooks worldwide.

The new table, outlined in a report released this month, will express atomic weights of 10 elements - hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine and thallium - in a new manner that will reflect more accurately how these elements are found in nature.

"For more than a century and a half, a number of were taught to use standard atomic weights a single value found on the inside cover of chemistry textbooks and on the periodic table of the elements. As technology improved, we have discovered that the numbers on our chart are not as static as we have previously believed," says Dr. Michael Wieser, an associate professor at the University of Calgary, who serves as secretary of the International Union of Pure and Applied Chemistry's (IUPAC) Commission on Isotopic Abundances and Atomic Weights. This organization oversees the assessment and dissemination of atomic-weight values.

Modern analytical techniques can measure the atomic weight of a number of elements precisely, and these small variations in an element's atomic weight are important in research and industry. For example, precise measurements of the abundances of isotopes of carbon can be used to determine purity and source of food, such as vanilla and honey. Isotopic measurements of nitrogen, chlorine and other elements are used for tracing pollutants in streams and groundwater. In sports doping investigations, performance-enhancing testosterone can be identified in the human body because the atomic weight of carbon in natural human testosterone is higher than that in pharmaceutical testosterone.........

Posted by: Sarah      Read more         Source


December 16, 2010, 7:57 AM CT

New method for making tiny catalysts

New method for making tiny catalysts
Photo by
L. Brian Stauffer
--------------------------------------------------------------------------------

Civil and environmental engineering professor Mark Rood (left) and graduate student John Atkinson developed a novel method of producing porous carbon spheres with iron dispersed throughout them for catalytic and air quality applications.

Fortified with iron: It's not just for breakfast cereal anymore. University of Illinois scientists have demonstrated a simpler method of adding iron to tiny carbon spheres to create catalytic materials that have the potential to remove contaminants from gas or liquid.

Civil and environmental engineering professor Mark Rood, graduate student John Atkinson and their team described their technique in the journal Carbon.

Carbon structures can be a support base for catalysts, such as iron and other metals. Iron is a readily available, low-cost catalyst with possible catalytic applications for fuel cells and environmental applications for adsorbing harmful chemicals, such as arsenic or carbon monoxide. Scientists produce a carbon matrix that has a number of pores or tunnels, like a sponge. The large surface area created by the pores provides sites to disperse tiny iron particles throughout the matrix.

A common source of carbon is coal. Typically, researchers modify coal-based materials into highly porous activated carbon and then add a catalyst. The multi-step process takes time and enormous amounts of energy. In addition, materials made with coal are plagued by ash, which can contain traces of other metals that interfere with the reactivity of the carbon-based catalyst.........

Posted by: Sarah      Read more         Source


December 13, 2010, 7:54 AM CT

Iron legacy leaves soil high in manganese

Iron legacy leaves soil high in manganese
The Shale Hills Critical Zone Observatory, part of the Critical Zone Exploration Network, is a small watershed located in Huntingdon County, Pa.

Credit: Elizebeth Herndon

Iron furnaces that once dotted central Pennsylvania may have left a legacy of manganese enriched soils, as per Penn State geoscientists. This manganese can be toxic to trees, particularly sugar maples, and other vegetation.

The research, which quantified the amounts of manganese in soil core samples, was part of work done at the Shale Hills Critical Zone Observatory funded by the National Science Foundation.

"Our group's focus was to study the soil chemistry," said Elizabeth M. Herndon, graduate student in geosciences. "We saw excess manganese in the soil and decided that we needed to quantify the manganese and determine where it came from".

Typically, manganese in soils comes from the disintegration of the bedrock as soil forms. Bedrock in this area is shale and the average amount of manganese in the shale is about 800 parts per million. However, the scientists found 14,000 parts per million of manganese in some of the soil samples. This is more than 17 times as much manganese as in the bedrock.

The scientists sampled 21 sites along a ridge at Shale Hills. They took core samples from the surface down to bedrock. At 20 of the sites they found elevated manganese. The core samples, which are about 12 inches long, encompass about 7,000 years of soil formation.........

Posted by: Tyler      Read more         Source


November 18, 2010, 7:16 AM CT

Rare Earth Elements Not So Rare

Rare Earth Elements Not So Rare
Approximately 13 million metric tons of rare earth elements (REE) exist within known deposits in the United States, as per the first-ever nationwide estimate of these elements by the U.S. Geological Survey.

This estimate of domestic rare earth deposits is part of a larger report that includes a review of global sources for REE, information on known deposits that might provide domestic sources of REE in the future, and geologic information crucial for studies of the availability of REE to U.S. industry.

The report describes significant deposits of REE in 14 states, with the largest known REE deposits at Mountain Pass, Calif.; Bokan Mountain, Alaska; and the Bear Lodge Mountains, Wyo. The Mountain Pass mine produced REE until it closed in 2002. Additional states with known REE deposits include Colorado, Florida, Georgia, Idaho, Illinois, Missouri, Nebraska, New Mexico, New York, North Carolina, and South Carolina.

"This is the first detailed evaluation of rare earth elements for the entire nation, describing deposits throughout the United States," commented USGS Director Marcia McNutt, Ph.D. "It will be very important, both to policy-makers and industry, and it reinforces the value of our efforts to maintain accurate, independent information on our nation's natural resources. Eventhough a number of of these deposits have yet to be proven, at recent domestic consumption rates of about 10,000 metric tons annually, the US deposits have the potential to meet our needs for years to come".........

Posted by: Sarah      Read more         Source


October 27, 2010, 7:00 AM CT

Six New Isotopes of the Superheavy Elements Discovered

Six New Isotopes of the Superheavy Elements Discovered
The six new isotopes placed on the chart of heavy nuclides.
A team of researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory has detected six isotopes, never seen before, of the superheavy elements 104 through 114. Starting with the creation of a new isotope of the yet-to-be-named element 114, the scientists observed successive emissions of alpha particles that yielded new isotopes of copernicium (element 112), darmstadtium (element 110), hassium (element 108), seaborgium (element 106), and rutherfordium (element 104). Rutherfordium ended the chain when it decayed by spontaneous fission.

Information gained from the new isotopes will contribute to a better understanding of the theory of nuclear shell structure, which underlies predictions of an "Island of Stability," a group of long-lasting isotopes thought to exist amidst a sea of much shorter-lived, intrinsically unstable isotopes of the superheavy elements.

The group that found the new isotopes is led by Heino Nitsche, head of the Heavy Element Nuclear and Radiochemistry Group in Berkeley Lab's Nuclear Science Division (NSD) and professor of chemistry at the University of California at Berkeley. Ken Gregorich, a senior staff scientist in NSD, is responsible for the group's day-to-day research operation at the 88-inch Cyclotron and the Berkeley Gas-filled Separator, the instrument used to isolate and identify the new isotopes. Paul Ellison of NSD, a graduate student in the UC Berkeley Department of Chemistry, formally proposed and managed the experiment and was first author of the paper reporting the results in the 29 October 2010 issue of Physical Review Letters, now available online to subscribers.........

Posted by: Sarah      Read more         Source


October 5, 2010, 7:22 AM CT

Europa's hidden ice chemistry

Europa's hidden ice chemistry
The icy surface of Europa is shown strewn with cracks, ridges and "chaotic terrain," where the surface has been disrupted and ice blocks have moved around. New laboratory experiments show that water ice and frozen sulfur dioxide react even at the frigid temperatures of Europa. Because the reaction occurs without the aid of radiation, it could take place throughout the moon's thick ice layer -- an outcome that would revamp current thinking about the chemistry and geology of this moon and perhaps others.

Credit: NASA/JPL/University of Arizona

The frigid ice of Jupiter's moon Europa appears to be hiding more than a presumed ocean: it is likely the scene of some unexpectedly fast chemistry between water and sulfur dioxide at extremely cold temperatures. Eventhough these molecules react easily as liquidsthey are well-known ingredients of acid rainMark Loeffler and Reggie Hudson at NASA's Goddard Space Flight Center in Greenbelt, Md., now report that they react as ices with surprising speed and high yield at temperatures hundreds of degrees below freezing. Because the reaction occurs without the aid of radiation, it could take place throughout Europa's thick coating of icean outcome that would revamp current thinking about the chemistry and geology of this moon and perhaps others.

"When people talk about chemistry on Europa, they typically talk about reactions that are driven by radiation," says Goddard scientist Mark Loeffler, the first author on the paper being published Oct. 2 in Geophysical Research Letters. That's because the moon's temperature hovers around 86 to 130 Kelvin, or about � to � F. In this extreme cold, most chemical reactions require an infusion of energy from radiation or light. On Europa, the energy comes from particles from Jupiter's radiation belts. Because most of those particles penetrate just fractions of an inch into the surface, models of Europa's chemistry typically stop there.........

Posted by: Brooke      Read more         Source


September 16, 2010, 8:56 AM CT

Neutrons unlock secrets to cheaper ethanol

Neutrons unlock secrets to cheaper ethanol
New insight into the structure of switchgrass and poplars is fueling discussions that could result in more efficient methods to turn biomass into biofuel.

Scientists from the Department of Energy's Oak Ridge National Laboratory and Georgia Tech used small-angle neutron scattering to probe the structural impact of an acid pretreatment of lignocellulose from switchgrass. Pretreatment is an essential step to extract cellulose, which can through a series of enzymatic procedures be converted into sugars and then ethanol. The findings, published in Biomacromolecules, could help researchers identify the most effective pretreatment strategy and lower the cost of the biomass conversion process.

"My hope is that this paper and subsequent discussions about our observations will lead to a better understanding of the complex mechanisms of lignocellulose breakdown," said co-author Volker Urban of ORNL's Chemical Sciences Division.

A key finding is that native switchgrass that has been pretreated with hot dilute sulfuric acid undergoes significant morphological changes. While the data demonstrate that the switchgrass materials are very similar at length scales greater than 1,000 angstroms, the materials are profoundly different at shorter lengths. An angstrom is equal to 1/10th of a nanometer.........

Posted by: Sarah      Read more         Source


May 21, 2010, 6:50 AM CT

Healthier vegetable oil and tractor fuel to harvest it

Healthier vegetable oil  and tractor fuel to harvest it
Developing fruit of Euonymus alatus, or burning bush. The white seed endosperm produces novel acetyl triacylglycerols, or acTAGs, while the orange aril tissue around the seed produces normal vegetable oil. Photo courtesy of Timothy Durrett, MSU

Genetic discoveries from a shrub called the burning bush, known for its brilliant red fall foliage, could fire new advances in biofuels and low-calorie food oils, as per Michigan State University scientists.

New low-cost DNA sequencing technology applied to seeds of the species Euonymus alatus - a common ornamental planting - was crucial to identifying the gene responsible for its manufacture of a novel, high-quality oil. But despite its name, the burning bush is not a suitable oil crop.

Yet inserted into the mustard weed - well-known to scientists as Arabidopsis and a cousin to commercial oilseed canola - the burning bush gene encodes an enzyme that produces a substantial yield of unusual compounds called acetyl glycerides, or acTAGs. Related vegetable oils are the basis of the world's oilseed industry for the food and biofuels markets, but the oil produced by the burning bush enzyme claims unique and valuable characteristics.

One is its lower viscosity, or thickness.

"The high viscosity of most plant oils prevents their direct use in diesel engines, so the oil must be converted to biodiesel," explained Timothy Durrett, an MSU plant biology research associate. "We demonstrated that acTAGs possess lower viscosity than regular plant oils. The lower viscosity acTAGs could therefore be useful as a direct-use biofuel for a number of diesel engines".........

Posted by: Sarah      Read more         Source


May 21, 2010, 6:48 AM CT

'Scrubbing' chemical-contaminated buildings

'Scrubbing' chemical-contaminated buildings
A "neodymium-YAG" laser will decompose VX nerve agent in this vinyl tile. Normally near-infrared, the laser turns ultraviolet as the frequency is increased. The UV light breaks the molecular bonds, decomposing the deadly nerve agent until it is just a harmless brown stain.

Credit: INL

Dhiren Barot was an al Qaeda operative involved in plots to blow up the London subway, among other targets. To maximize the damage and the terror, he planned to pack some of his bombs with toxic gas. Fortunately, in August 2004, British authorities nabbed Barot and his accomplices before they could carry out their attacks.

But the threat of a gas attack remains. Where Barot failed, at some point someone might succeed. The right response to such an attack could minimize exposure and save hundreds of thousands of American lives.

With funding and guidance from the Department of Homeland Security's Science and Technology Directorate (S&T), chemists at Idaho National Laboratory (INL) are researching ways to help the nation respond to and clean up after potential chemical attacks. They have been studying decontamination techniques for almost a decade.

Cleaning up chemical-contaminated structures can be difficult, costly, and time-consuming. For one thing, most preferred methods employ other chemicals, like bleach solutions, which can be corrosive and aggressive. A number of building materialslike cement and brickare extremely porous and getting contaminants off such surfaces is difficult, as contaminants will seep into cracks and pores.

As per Donald Bansleben, program manager in S&T's Chemical and Biological Division, lasers could one day play a big role. "Lasers could help to scrub chemical-contaminated buildings clean and become a tool in the toolbox to speed a facility's return to normal operations".........

Posted by: Sarah      Read more         Source


March 22, 2010, 8:03 PM CT

New bacteria strain to make super bread

New bacteria strain to make super bread
Sourdough bread could be even tastier and more healthful thanks to a new strain of bacteria reported at the American Chemical Society meeting.

Credit: iStock

What better venue than San Francisco sourdough capital of the world to unveil a new natural sourdough ingredient that could replace conventional additives in a variety of other breads, while making them tastier and more healthful? And that's what researchers described today at the American Chemical Society's 239th National Meeting, being held here.

In the study, Maija Tenkanen, Ph.D., and his colleagues reported discovery and use of a new strain of bacteria that convert the sugars in bread dough into produce dextrans. Dextrans are sugar molecules associated withgether into long chains that improve the texture and taste of the sourdough and help keep the bread fresh. These bacteria are available commercially, but produce large amounts of lactic acid along with dextrans.

"The advantage of this new strain of bacteria is that while it produces 10 times more dextran than products on the market now, it doesn't produce large amounts of acid," Tenkanen said. "Because of this feature, and because the added amount of natural dextran could actually improve the flavor, this could be used in place of additives for a broad variety of breads".

She also said the new dextrans may act as so-called "prebiotics," non-digestible food ingredients that stimulate the growth or activity of bacteria in the digestive system which are beneficial to health.........

Posted by: Sarah      Read more         Source


March 17, 2010, 7:54 PM CT

Solving hydrogen storage issues

Solving hydrogen storage issues
A graphene-oxide framework (GOF) is formed of layers of graphene connected by boron-carboxylic "pillars." GOFs such as this one are just beginning to be explored as a potential storage medium for hydrogen and other gases.

Credit: NIST

Graphenecarbon formed into sheets a single atom thicknow may be a promising base material for capturing hydrogen, as per recent research* at the National Institute of Standards and Technology (NIST) and the University of Pennsylvania. The findings suggest stacks of graphene layers could potentially store hydrogen safely for use in fuel cells and other applications.

Graphene has become something of a celebrity material in recent years due to its conductive, thermal and optical properties, which could make it useful in a range of sensors and semiconductor devices. The material does not store hydrogen well in its original form, as per a team of researchers studying it at the NIST Center for Neutron Research. But if oxidized graphene sheets are stacked atop one another like the decks of a multilevel parking lot, connected by molecules that both link the layers to one another and maintain space between them, the resulting graphene-oxide framework (GOF) can accumulate hydrogen in greater quantities.

Inspired to create GOFs by the metal-organic frameworks that are also under scrutiny for hydrogen storage, the team is just beginning to uncover the new structures' properties. "No one else has ever made GOFs, to the best of our knowledge," says NIST theorist Taner Yildirim. "What we have found so far, though, indicates GOFs can hold at least a hundred times more hydrogen molecules than ordinary graphene oxide does. The easy synthesis, low cost and non-toxicity of graphene make this material a promising candidate for gas storage applications".........

Posted by: Sarah      Read more         Source


February 18, 2010, 9:48 PM CT

Oil droplets can navigate complex maze

Oil droplets can navigate complex maze
Simple oil droplets (in red) can navigate a complex maze using a special chemical approach that could lead to improved delivery of anti-cancer drugs.

Credit: American Chemical Society

Call them oil droplets with a brain or even "chemo-rats." Researchers in Illinois have developed a way to make simple oil droplets "smart" enough to navigate through a complex maze almost like a trained lab rat. The finding could have a wide range of practical implications, including helping cancer drugs to reach their target and controlling the movement of futuristic nano-machines, the researchers say. Their study is in the weekly Journal of the American Chemical Society

Bartosz Grzybowski and his colleagues note that the ability to solve a maze is a common scientific test of intelligence. Animals ranging from rats to humans can master the task. Researchers would like to pass along that same ability to anti-cancer drugs, for instance, to help these medications navigate complex mazes of blood vessels and reach the tumor.

The researchers describe an advance in that direction. They developed postage-stamp-sized mazes, and infused them with an alkaline solution, and placed a gel containing a strong acid at the exit. That created a pH gradient, a difference between the acid-alkaline levels. Oil droplets containing a weak acid placed at the entrance of the mazes developed convective flows in response to pH differences and propelled themselves along the gradient toward the exit. Since cancer cells are more acidic than other body cells, the experiment may serve as a model for designing new anti-cancer drugs that move along similar acid-based gradients to target diseased cells, the researchers suggest.........

Posted by: Sarah      Read more         Source


February 11, 2010, 8:04 AM CT

Mercury in Arctic snow

Mercury in Arctic snow
A study by University of Michigan scientists offers new insight into what happens to mercury deposited onto Arctic snow from the atmosphere.

The work also provides a new approach to tracking mercury's movement through Arctic ecosystems.

Mercury is a naturally occurring element, but some 2000 tons of it enter the global environment each year from human-generated sources such as coal-burning power plants, incinerators and chlorine-producing plants.

"When released into the atmosphere in its reduced form, mercury is not very reactive. It can float around in the atmosphere as a gas for a year or more, and it's not really an environmental problem at the concentrations at which it occurs," said Joel Blum, the John D. MacArthur Professor of Geological Sciences.

But once mercury is oxidized, through a process that involves sunlight and often the element bromine, it becomes very reactive. Deposited onto land or into water, the mercury is picked up by microorganisms, which convert some of it to methylmercury, a highly toxic form that builds up in fish and the animals that eat them.

As bigger animals eat smaller ones, the methylmercury is concentrated. In wildlife, exposure to methylmercury can interfere with reproduction, growth, development and behavior and may even cause death. Effects on humans include damage to the central nervous system, heart and immune system. The developing brains of young and unborn children are particularly vulnerable.........

Posted by: Tyler      Read more         Source


February 3, 2010, 2:28 PM CT

Reverses paralysis with a beam of light

Reverses paralysis with a beam of light
This tiny worm became temporarily paralyzed when scientists fed it a light-sensitive material, or "photoswitch," and then exposed it to ultraviolet light.

Credit: American Chemical Society

In an advance with overtones of Star Trek phasers and other sci-fi ray guns, researchers in Canada are reporting development of an internal on-off "switch" that paralyzes animals when exposed to a beam of ultraviolet light. The animals stay paralyzed even when the light is turned off. When exposed to ordinary light, the animals become unparalyzed and wake up. Their study appears in the Journal of the American Chemical Society (JACS). It reports the first demonstration of such a light-activated switch in animals.

Neil Branda and his colleagues point out that such "photoswitches" light-sensitive materials that undergo photoreactions have been available for years. Researchers use them in research. Doctors use light-sensitive materials and photoreactions in medicine in photodynamic treatment to treat certain forms of cancer. Those light-sensitive materials, however, do not have the reversibility that exists in photoswitching.

The JACS report describes development and successful testing of a photoswitch composed of the light-sensitive material, dithienylethene. The researchers grew transparent, pinhead-sized worms (C. elegans) and fed them a dithienylethene. When exposed to ultraviolet light, the worms turned blue and became paralyzed. When exposed to visible light, the dithienylethene became colorless again and the worms' paralysis ended. A number of of the worms lived through the paralyze-unparalyze cycle. Researchers were not sure how the switch causes paralysis. The study demonstrates that photoswitches may have great potential in turning photodynamic treatment on and off, and for other applications in medicine and research, they indicate.........

Posted by: Sarah      Read more         Source


February 3, 2010, 7:53 AM CT

Synthesis of hydrogen fuel storage material may become less complicated

Synthesis of hydrogen fuel storage material may become less complicated
This image illustrates that an applied electric field polarizes hydrogen molecules and the substrate, inducing hydrogen absorption with good thermodynamics and kinetics. Image courtesy of Qian Wang, Ph.D./VCU.
An international team of scientists has identified a new theoretical approach that may one day make the synthesis of hydrogen fuel storage materials less complicated and improve the thermodynamics and reversibility of the system.

A number of scientists have their sights set on hydrogen as an alternative energy source to fossil fuels such as oil, natural gas and coal that contain carbon, pollute the environment and contribute to global warming. Known to be the most abundant element in the universe, hydrogen is considered an ideal energy carrier - not to mention that it's clean, environmentally friendly and non-toxic. However, it has been difficult to find materials that can efficiently and safely store and release it with fast kinetics under ambient temperature and pressure.

The team of scientists from Virginia Commonwealth University ; Peking University in Beijing; and the Chinese Academy of Science in Shanghai; have developed a process using an electric field that can significantly improve how hydrogen fuel is stored and released.

"Eventhough tremendous efforts have been devoted to experimental and theoretical research in the past years, the biggest challenge is that all the existing methods do not meet the Department of Energy targets for hydrogen storage materials. The breakthrough can only be achieved by exploring new mechanisms and new principles for materials design," said Qiang Sun, Ph.D., research associate professor with the VCU team, who led the study.........

Posted by: Sarah      Read more         Source


December 29, 2009, 8:46 AM CT

New perspective on periodic table

New perspective on periodic table
Transforming lead into gold is an impossible feat, but a similar type of "alchemy" is not only possible, but cost-effective too. Three Penn State scientists have shown that certain combinations of elemental atoms have electronic signatures that mimic the electronic signatures of other elements. As per the team's leader A. Welford Castleman Jr., Eberly Distinguished Chair in Science and Evan Pugh Professor in the Departments of Chemistry and Physics, "the findings could lead to much cheaper materials for widespread applications such as new sources of energy, methods of pollution abatement, and catalysts on which industrial nations depend heavily for chemical processing".

The scientists also showed that the atoms that have been identified so far in these mimicry events can be predicted simply by looking at the periodic table. The team used advanced experimentation and theory to quantify these new and unexpected findings. "We're getting a whole new perspective of the periodic table," said Castleman. The team's findings would be reported in the 28 December 2009 early on-line issue of the journal Proceedings of the National Academy of Sciences, and at a later date in the print edition of the journal.

Castleman and his team -- which includes Samuel Peppernick, a former Penn State graduate student who now is a postdoctoral researcher at the Pacific Northwest National Laboratory, and Dasitha Gunaratne, a Penn State graduate student -- used a technique, called photoelectron imaging spectroscopy, to examine similarities between titanium monoxide and nickel, zirconium monoxide and palladium, and tungsten carbide and platinum. "Photoelectron spectroscopy measures the energy it takes to remove electrons from various electronic states of atoms or molecules, while simultaneously capturing snapshots of these electron-detachment events with a digital camera," said Castleman. "The method allows us to determine the binding energies of the electrons and also to observe directly the nature of the orbitals in which the electrons resided before they were detached. We observed that the amount of energy mandatory to remove electrons from a titanium-monoxide molecule is the same as the amount of energy mandatory to remove electrons from a nickel atom. The same is true for the systems zirconium monoxide and palladium and tungsten carbide and platinum. The key is that all of the pairs are composed of isoelectronic species, which are atoms with the same electron configuration." Castleman noted that, in this case, the term isoelectronic refers to the number of electrons present in the outer shell of an atom or molecule.........

Posted by: Sarah      Read more         Source

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