Tag Archives: Berkeley

The Best of Both Catalytic Worlds

By Guest PostOctober 13, 2012ScienceBerkeley, berkeley lab, biochemistry, biomolecule, california, cancer, catalysis program, catalyst, catalytic reactivity, chemical reaction, cholesterol medicine, complex reaction, cyclopropanation reaction, cyclopropane, dean toste, dendrimers, elad gross, enzyme, gabor somorjai, gold nanocluster, heterogeneous, homogeneous, industrial catalyst, metal catalysts, metal nanocluster, molecule, palladium, pamam, platinum, product selectivity, property, protein, recyclability, rhodium, substance, university

Berkeley Lab Researchers Develop New Technique for Heterogenizing Homogenous Nano Catalysts

Catalysts are substances that speed up the rates of chemical reactions without themselves being chemically changed. Industrial catalysts come in two main types – heterogeneous, in which the catalyst is in a different phase from the reactants; and homogeneous, in which catalyst and the reactants are in the same phase. Heterogeneous catalysts are valued for their sustainability because they can be recycled. Homogeneous catalysts are valued for their product selectivity as their properties can be easily tuned through relatively simple chemistry.

Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have combined the best properties of both types of industrial catalysts by encapsulating nanoclusters of a metallic heterogeneous catalyst within the branched arms of the molecules known as dendrimers. (more…)

First Stars, Galaxies Formed more Rapidly than Expected

By Guest PostSeptember 9, 2012Scienceanalysis, anisotropy probe, Antarctica, astronomer, background, Berkeley, california, christian reichardt, cmb, cosmic microwave, cosmological evolution, data, earth axis, electron, Epoch, Galaxy, geographic, herschel satellite, high resolution, hydrogen atom, image, john carlstrom, kavli foundation, microwave, millimeter wavelength, national, neutral, neutral gas, oliver zahn, period, plasma, polar plateau, proton, radiation, reionization, s chandrasekhar, science foundation, south pole, star, telescope, ultraviolet light, universe, university, wilkinson

Analysis of data from the National Science Foundation’s South Pole Telescope, for the first time, more precisely defines the period of cosmological evolution when the first stars and galaxies formed and gradually illuminated the universe. The data indicate that this period, called the epoch of reionization, was shorter than theorists speculated — and that it ended early.

“We find that the epoch of reionization lasted less than 500 million years and began when the universe was at least 250 million years old,” said Oliver Zahn, a postdoctoral fellow at the Berkeley Center for Cosmological Physics at the University of California, Berkeley, who led the study. “Before this measurement, scientists believed that reionization lasted 750 million years or longer, and had no evidence as to when reionization began.” (more…)

Nano-Sandwich Technique Slims Down Solar Cells, Improves Efficiency

By Guest PostJune 29, 2012Scienceamorphous silicon, Berkeley, cadmium telluride, chemical fuel, efficiency, electricity, linyou cao, nano-sandwich, nanometer, nanostructures, nm, organic materials, paul alivisatos, solar cells, solar energy, substrate, technique, Technology, university of california, vivian ferry

Researchers from North Carolina State University have found a way to create much slimmer thin-film solar cells without sacrificing the cells’ ability to absorb solar energy. Making the cells thinner should significantly decrease manufacturing costs for the technology.

“We were able to create solar cells using a ‘nanoscale sandwich’ design with an ultra-thin ‘active’ layer,” says Dr. Linyou Cao, an assistant professor of materials science and engineering at NC State and co-author of a paper describing the research. “For example, we created a solar cell with an active layer of amorphous silicon that is only 70 nanometers (nm) thick. This is a significant improvement, because typical thin-film solar cells currently on the market that also use amorphous silicon have active layers between 300 and 500 nm thick.” The “active” layer in thin-film solar cells is the layer of material that actually absorbs solar energy for conversion into electricity or chemical fuel. (more…)

A New Tool to Attack the Mysteries of High-Temperature Superconductivity

By Guest PostJune 8, 2012Scienceabsolute zero, advanced light source, alessandra lanzara, als, band structure, bardeen cooper schrieffer, bcs theory, beams of xrays, Berkeley, berkeley lab, bi2212, christopher smallwood, conventional superconductors, cooper pairs, dung hai lee, electric current, electric grids, electrons, energy savings, femtosecond scale pulses, high tc, high temperature, joseph orenstein, msd, quasiparticles, relaxation process, resistance, superconductivity, synchrotron light sources, through frequency, transmission, ultrafast laser arpes, university of california

Berkeley Lab researchers use an ultrafast laser to better understand high-temperature superconductors

Superconductivity, in which electric current flows without resistance, promises huge energy savings – from low-voltage electric grids with no transmission losses, superefficient motors and generators, and myriad other schemes. But such everyday applications still lie in the future, because conventional superconductivity in metals can’t do the job.

Although they play important roles in science, industry, and medicine, conventional superconductors must be maintained at temperatures a few degrees above absolute zero, which is tricky and expensive. Wider uses will depend on higher-temperature superconductors that can function well above absolute zero. Yet known high-temperature (high-Tc) superconductors are complex materials whose electronic structures, despite decades of work, are still far from clear. (more…)

Ice Age Mariners From Europe Were Among America’s First People

By Guest PostFebruary 29, 2012Scienceacross atlantic ice, alaska, america, asia, bering sea, Berkeley, boat, bruce bradley, cities of gold, clovis, clovis culture, dennis stanford, douglas preston, earliest humans, Europe, last ice age, native americans, new mexico, new world, North America, northern spain, orthodoxy, paradigm, sea ice shelf, smithsonian institution, solutrean people, thunderhead, united states, university california press, university of exeter

Some of the earliest humans to inhabit America came from Europe according to a new book.

Across Atlantic Ice puts forward a compelling case for people from northern Spain travelling to America by boat, following the edge of a sea ice shelf that connected Europe and America during the last Ice Age, 14,000 to 25,000 years ago.

Across Atlantic Ice is the result of more than a decade’s research by leading archaeologists Professor Bruce Bradley of the University of Exeter and Dr Dennis Stanford of the Smithsonian Institution. Through archaeological evidence, they turn the long-held theory of the origins of New World populations on its head.

For more than 400 years, it has been claimed that people first entered America from Asia, via a land bridge that spanned the Bering Sea. We now know that some people did arrive via this route nearly 15,000 years ago, probably by both land and sea. (more…)

Charles P. Sonett: the Legacy of a Pioneering Space Scientist

By Guest PostOctober 9, 2011Scienceames magnetic fields explorer, apollo program, arizona board of regents, astronomy, Berkeley, bernhard schmidt, charles chuck p sonett, charles p sonett, charles p sonett space sciences building, chuck, cycle, death valley, desert town, estonian optician, explorer 33 and 35, explorer program, geology, geophysical measurements, george willis ritchey, gerard p kuiper, global climate, henri jacques chrétien, hollywood high school, hungarian parents, j randy jokipii, japanese bombing of pearl harbor, los angeles, lpl, lunar and planetary laboratory, lunar orbiter magnetometer experiment, magnetosphere, michael j drake, pittsburgh, post apollo era, ritchey chrétien telescope, schmidt telescope, solar wind, space race, spacecraft, spacecraft missions, sputnik, stream of charged particles, sun, telescope optics, trona, university of california, us army air forces

*Charles P. Sonett, the first head of the UA’s department of planetary sciences, died at the age of 87. Sonett was involved in spacecraft missions that dramatically advanced our understanding of the solar system and beyond, including the Pioneer Program, the Explorer Program and the Apollo Program.*

Charles “Chuck” P. Sonett, a founding faculty member and the first department head of the University of Arizona’s department of planetary sciences, died on Sept. 30. He was 87.

As a space exploration pioneer, Sonett was involved in numerous spacecraft programs, including the Pioneer Program, the Explorer Program and the Apollo Program – missions that dramatically advanced our understanding of the solar system, its planets and moons and beyond. (more…)

Shade-coffee farms support native bees that help maintain genetic diversity in remnant tropical forests

By Guest PostJuly 27, 20101 commentEnvironment, Natureafricanized honeybees, Berkeley, biodiverse tropical regions, biodiversity, biologist, buzz, canopy of trees, chiapas, christopher dick, ecology, evolutionary biology, m. affinis, Mexico, miconia affinis, migratory birds, native bees, native trees, pollination, role, saquiyac tree, shade-coffee farms, shade-grown coffee, shalene jha, tropical forest, university of california, university of michigan

ANN ARBOR, Mich. — Shade-grown coffee farms support native bees that help maintain the health of some of the world’s most biodiverse tropical regions, according to a study by a University of Michigan biologist and a colleague at the University of California, Berkeley.

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1200 Howler Monkeys on Panama’s Barro Colorado Island

By Guest PostJune 29, 20102 commentsNatureanita arcia mendoza, astrocaryum, barro Colorado, Berkeley, bot fly, bot fly lesion, claudio monteza, cuterebra baeri, darlene mitre, david natera, dawn chorus, department of environmental science and policy manageme, first howl, greg willis, howler monkey, island, jose alejandro ramirez silva, karis tunon, katie Milton, luis yepes, orlando ortiz castillo, panama, Smithsonian, stalwart volunteers, stri, triangulation, university of california, university of panama

The fifth Howler Monkey census at the Smithsonian’s Barro Colorado Island research station in Panama, organized by Katie Milton, professor in the department of Environmental Science, Policy & Management at the University of California, Berkeley, revealed that monkey numbers have not changed significantly since the first census 33 years ago.

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