Tag Archives: berkeley lab

New Path to More Efficient Organic Solar Cells Uncovered at Berkeley Lab’s Advanced Light Source

By Guest PostJanuary 12, 2013Environmentacceptor, advanced light source, affordable, als, als beamlines, amount, berkeley lab, brian collins, christopher mcneill, convert, crystallinity, donor, earth, efficient, electricity, eliot gann, energy use, exciton journey, fossil fuels, fullerene solar film, harald ade, john tumbleston, land mass, nanometers, north Carolina, organic cell, photovoltaic cells, photovoltaic devices, physicist, polymer, r soxs, research, resonant soft, silicon based, size matters, solar cell, solar energy, solvent diiodooctane, state university, stxm, sunlight, ultraviolet light beams, volume, x ray, x ray scattering, zhe li

Why are efficient and affordable solar cells so highly coveted? Volume. The amount of solar energy lighting up Earth’s land mass every year is nearly 3,000 times the total amount of annual human energy use. But to compete with energy from fossil fuels, photovoltaic devices must convert sunlight to electricity with a certain measure of efficiency. For polymer-based organic photovoltaic cells, which are far less expensive to manufacture than silicon-based solar cells, scientists have long believed that the key to high efficiencies rests in the purity of the polymer/organic cell’s two domains – acceptor and donor. Now, however, an alternate and possibly easier route forward has been shown.

Working at Berkeley Lab’s Advanced Light Source (ALS), a premier source of X-ray and ultraviolet light beams for research, an international team of scientists found that for highly efficient polymer/organic photovoltaic cells, size matters. (more…)

How Computers Push on the Molecules They Simulate

By Guest PostJanuary 9, 2013Scienceacceleration, albert einstein, algorithm, analytical results, artifacts, atoms and molecules, behavior, Berkeley, berkeley lab, calculation, california, california institute, chemical fuel, collide, computer method, conserve energy, david sivak, digital representation, digitize time, dna repair, driving force, effective friction, energy dense, equation, error, finite time steps, fluid, french physicist, gavin crooks, john chodera, langevin dynamics, model brownian motion, modeling molecular system, modern computer, molecular machines, molecular scale motion, molecule, momentum, natural system, nonequilibrium driving force, nonequilibrium statistical mechanics, particle, passage of time, paul langevin, photosynthesis, pollen grain, qb3, quantitative biosciences, quantum mechanics, real world, simulation, source, tenacious errors, theoretical method, thermal energy, toy models, university, velocity, water, water molecules

Berkeley Lab bioscientists and their colleagues decipher a far-reaching problem in computer simulations

Because modern computers have to depict the real world with digital representations of numbers instead of physical analogues, to simulate the continuous passage of time they have to digitize time into small slices. This kind of simulation is essential in disciplines from medical and biological research, to new materials, to fundamental considerations of quantum mechanics, and the fact that it inevitably introduces errors is an ongoing problem for scientists.

Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have now identified and characterized the source of tenacious errors and come up with a way to separate the realistic aspects of a simulation from the artifacts of the computer method. The research was done by David Sivak and his advisor Gavin Crooks in Berkeley Lab’s Physical Biosciences Division and John Chodera, a colleague at the California Institute of Quantitative Biosciences (QB3) at the University of California at Berkeley. The three report their results in Physical Review X. (more…)

A New Way to Study Permafrost Soil, Above and Below Ground

By Guest PostJanuary 6, 2013Environmentarctic landscape, arctic tundra, atmosphere, barrow region, berkeley lab, carbon dioxide, cessna aircraft, climate change, electrical resistance tomography, electromagnetic data, geophysical measurements, greenhouse gasses, ground penetrating radar, large spatial scales, lidar, lidar airborne measurements, methane, microtopography, ngee arctic project, permafrost layer, permafrost soils, polygons, remote sensing device, remote sensing tools, surface topography, susan hubbard, terrestrial ecosystem, trapped carbon

Berkeley Lab research could lead to a better understanding of the Arctic ecosystem’s impact on the planet’s climate

What does pulling a radar-equipped sled across the Arctic tundra have to do with improving our understanding of climate change? It’s part of a new way to explore the little-known world of permafrost soils, which store almost as much carbon as the rest of the world’s soils and about twice as much as is in the atmosphere.

The new approach combines several remote-sensing tools to study the Arctic landscape—above and below ground—in high resolution and over large spatial scales. It was developed by a group of researchers that includes scientists from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). (more…)

Boosting Galactan Sugars Could Boost Biofuel Production

By Guest PostDecember 23, 2012Environmentai oikawa, april liwanag, arabidopsis thaliana, atmosphere, berit ebert, berkeley lab, bioenergy fuel crops, biofuels, carbon neutral, carsten rautengarten, cellulosic biomass, denmark, diesel, emilie rennie, enzyme, ethanol, ferment, fuels, galactan, galactan synthase, galactose, gals1, gals2, gals3, gasoline, gt92 enzyme, gt92 proteins, henrik scheller, jet fuels, mads clausen, mathias andersen, mechanical stress, miscanthus, overexpressors, pentoses, plant cell walls, polymer, six carbon sugar, snowfall, switchgrass, technical university, wind, yeast, yves verhertbruggen, β galactan synthase

Collaboration at JBEI Identifies the First Enzyme Linked to Galactan Synthesis

Galactan is a polymer of galactose, a six-carbon sugar that can be readily fermented by yeast into ethanol and is a target of interest for researchers in advanced biofuels produced from cellulosic biomass. Now an international collaboration led by scientists at the U.S. Department of Energy (DOE)’s Joint BioEnergy Institute (JBEI) has identified the first enzyme capable of substantially boosting the amount of galactan in plant cell walls.

Unlike ethanol, advanced biofuels synthesized from the sugars in plant cells walls could replace gasoline, diesel and jet fuels on a gallon-for-gallon basis and be dropped into today’s engines and infrastructures with no modifications required. Also, adanced biofuels have the potential to be carbon-neutral, meaning they could be burned without adding excess carbon to the atmosphere. Among the key challenges to making advanced biofuels cost competitive is finding ways to maximize the amount of plant cell wall sugars that can be fermented into fuels. (more…)

Flexing Fingers for Micro-Robotics: Berkeley Lab Scientists Create a Powerful, Microscale Actuator

By Guest PostDecember 18, 2012Scienceartificial muscles, beckoning finger, berkeley lab, chromium metal layer, chun cheng, electron, electronic behaviors, flex, human muscle cells, junqiao wu, kai liu, kevin wang, metal, microactuator, microfluidics, micron, microscale actuator, natural application, oxide material, phase transitions, phenomena, phillip m. duxbury, piezoelectric device, piezoelectric technology, ramamoorthy ramesh, subhendra d mahanti, Technology, temperature variation, university of california, vanadium dioxide, zhenting cheng

Berkeley, Calif., Dec. 2012 — Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Berkeley, have developed an elegant and powerful new microscale actuator that can flex like a tiny beckoning finger. Based on an oxide material that expands and contracts dramatically in response to a small temperature variation, the actuators are smaller than the width of a human hair and are promising for microfluidics, drug delivery, and artificial muscles.

“We believe our microactuator is more efficient and powerful than any current microscale actuation technology, including human muscle cells,” says Berkeley Lab and UC Berkeley scientist Junqiao Wu. “What’s more, it uses this very interesting material—vanadium dioxide—and tells us more about the fundamental materials science of phase transitions.” (more…)

Nanocrystals Not Small Enough to Avoid Defects

By Guest PostDecember 15, 2012Scienceals, berkeley lab, bin chen, computer simulation, crystal, defect, dislocation, gas turbine, grains, high pressure, jet engine, jialin lei, jinyuan yan, katie lutker, mechanical properties, metal, nanocrystal, nanocrystalline nickel, nanometer, nickel, non metal, plastic deformation, protective coating, resistance, selva vennila raju, stress, ultraviolet light, waruntorn kanitpanyacharoen

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…)

Seeing in Color at the Nanoscale

By Guest PostDecember 12, 2012Scienceafm, alex weber bargioni, atomic force microscope, atomic microscopy, berkeley lab, color, conversion, data, diederik wiersma, electric energy, electrons, fabrication, far field light, francesca intonti, frank ogletree, geometries, imagery, indium phosphide nanowires, james schuck, jeffrey bokor, mauro meli, multidimensional, nano optics, nanoscale, nanoscale objects, nanoscience, nanospectroscopic imaging, optical fiber, optical spectroscopy, optoelectronic properties, photons, plasmons, shaul aloni, solar, stephano cabrini, sub nanoscale resolution, topological map, wei bao

Berkeley Lab scientists develop a new nanotech tool to probe solar-energy conversion

If nanoscience were television, we’d be in the 1950s. Although scientists can make and manipulate nanoscale objects with increasingly awesome control, they are limited to black-and-white imagery for examining those objects. Information about nanoscale chemistry and interactions with light—the atomic-microscopy equivalent to color—is tantalizingly out of reach to all but the most persistent researchers.

But that may all change with the introduction of a new microscopy tool from researchers at the Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) that delivers exquisite chemical details with a resolution once thought impossible. The team developed their tool to investigate solar-to-electric energy conversion at its most fundamental level, but their invention promises to reveal new worlds of data to researchers in all walks of nanoscience. (more…)

More Potent than Carbon Dioxide, Nitrous Oxide Levels in California May be Nearly Three Times Higher Than Previously Thought

By Guest PostDecember 9, 2012Environmentagricultural production, atmospheric measurement, berkeley lab, biogeochemical process, bottom up inventory, california, carbon dioxide, CO2, cycle of emissions, edgar, emission, environmental condition, estimate, factor, fossil fuel, greenhouse gas, laughing gas, level, marc fischer, methane, model prediction, moisture, new method, nitrogen fertilizer, nitrous oxide, noaa, temperature, total n2o, type of soil, walnut grove

Berkeley Lab researchers devise a new method to estimate state’s greenhouse gas emissions.

Using a new method for estimating greenhouse gases that combines atmospheric measurements with model predictions, Lawrence Berkeley National Laboratory (Berkeley Lab) researchers have found that the level of nitrous oxide, a potent greenhouse gas, in California may be 2.5 to 3 times greater than the current inventory.

At that level, total N₂O emissions—which are believed to come primarily from nitrogen fertilizers used in agricultural production—would account for about 8 percent of California’s total greenhouse gas emissions. The findings were recently published in a paper titled “Seasonal variations in N₂O emissions from central California” in Geophysical Research Letters. Earlier this year, using the same methodology, the researchers found that levels of methane, another potent greenhouse gas, in California may be up to 1.8 times greater than previous estimates. (more…)