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Graphene Sheet Scientists have found that nanoripples in graphene make it a strong catalyst, even though it was expected to be chemically inert. Their research, published in PNAS, demonstrated that nanoscale corrugations on graphene’s surface accelerate hydrogen splitting as well as the best metallic-based catalysts, and this effect may be present in all 2D materials. *********************************************************************** A team of researchers led by Prof. Andre Geim from the National Graphene Institute (NGI) have discovered that nanoripples in graphene can make it a strong catalyst, contrary to general expectations that the carbon sheet is as chemically inert as the bulk graphite from...

Cracks in the universe: the search for cosmic strings Galaxy-sized filaments of raw energy may be threaded through spacetime, according to some theories. Will we ever find traces of them? Cathal O’Connell takes up the hunt. Share Tweet Tatyun / Getty Images Our universe exploded into being, expanded at a fantastic speed and cooled. Perhaps too quickly. Some physicists believe the rapid cooling might have cracked the fabric of the universe.These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The...

The Corrugated Galaxy The disk of the Milky Way Galaxy disk may actually be rippled. Two ringlike structures of stars wrapping around the Milky Way's outer disk now appear to belong to the disk itself. The results, outlined in a new study, show that the disk is about 60 percent larger than previously thought. Not only do the results extend the size of the Milky Way, they also reveal a rippling pattern, which raises intriguing questions about what sent wavelike fluctuations rippling through the disk. The researchers said the likely culprit was a dwarf galaxy. It might have plunged...

There is little remaining controversy over the measures necessary to thwart terrorism. After the radical Islamist attacks on the World Trade Center and the Pentagon, and the foiled effort to ram a fourth jet into the Capitol in Washington, no one envisioned that there would follow eleven years without another major attack. Since September 11, 2001, over 45 terrorist plots have been uncovered and foiled in the United States; al-Qaeda, as a terrorist threat, seems regionalized and without the ability to inflict mayhem on a similarly large scale on the Western world; bin Laden is no more; and the Arab...

Two kinds of sand ripples exist: normal, small ripples and megaripples with wavelengths reaching up to several meters. They differ also in their grain-size distributions (unimodal for sand ripples and bimodal for megaripples). While sand ripples form almost straight lines, megaripples have greater sinuosity due to their transverse instability, a property that causes small megaripple undulations to grow with time. The origin of the instability is due to variations in megaripple height, which do not diminish over time, as well as to the inverse dependence of ripple drift velocity on height. Thus, the taller regions of ripples will move more...

The global credit crisis has slammed into Europe with stunning violence over the last two days, triggering five major bank rescues and a near total shut-down of the region's credit markets. The Dutch-Belgian bank Fortis, Britain's Bradford and Bingley, and Iceland's Glitnir, were all partially or fully nationalized after failing to roll-over debts in the short-term money markets, while the French state pledged support for the Franco-Belgian lender Dexia after the share price collapsed on reports of a capital shortage. "The European financial sector is on trial: we have to support our banks." said French President Nicolas Sarkozy. He has...

Minimum Wage Ripples Michael Arnold Glueck, M.D., and Robert J. Cihak, M.D., The Medicine Men Tuesday, Nov. 21, 2006 The impacts of minimum wage laws on marginally productive workers are well known among thoughtful and economically minded people. I think the voters in the states which passed ballot initiatives increasing the minimum wage in their states were not aware of the ill effects of such laws. As Thomas Sowell writes, "Young, inexperienced and unskilled workers are especially likely to find it harder to get a job when wage rates have been set higher than the value of their productivity." If...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 November 11 The Outer Shells of Centaurus A Credit: E. Peng and H. Ford (JHU), K. Freeman (ANU), R. White (STScI), CTIO, NOAO, NSF Explanation: What causes the surrounding shells in peculiar galaxy Cen A? Last month a fascinating image of peculiar galaxy Centaurus A was released, processed to highlight a faint blue arc indicating an ongoing collision with a smaller galaxy. Another interesting feature of Cen...