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Iran’s nuclear ambitions have already started a war with west – a covert one

Iran’s nuclear ambitions have already started a war with west – a covert one

A secret campaign of surveillance, sabotage, cyberattacks and assassinations has slowed but not stopped Tehran’s programme

President George W Bush in 2007

Iran’s nuclear ambitions led then US president George W Bush to launch a covert war in 2007 to thwart the programme. Photograph: Jim Young/REUTERS

The covert war on Iran‘s nuclear programme was launched in earnest by George Bush in 2007. It is a fair assumption that the western powers had been trying their best to spy on the Islamic Republic since the 1979 Iranian revolution, but the 2007 “presidential finding” put those efforts on a new footing.

Bush asked Congress to approve $400m for a programme of support for rebel ethnic groups, as well as intelligence gathering and sabotage of the nuclear programme. Part of that effort involved slipping defective parts such as centrifuge components into the black market supply to Iran, designed to blow apart while in operation and in so doing bring down all the centrifuges in the vicinity. The UK, Germany, France and Israel are said to have been involved in similar efforts. Meanwhile, western intelligence agencies stepped up their attempt to infiltrate the programme, seeking to recruit Iranian scientists when they travelled abroad.

That espionage effort appears to have paid dividends. In 2009, the US, British and French intelligence agencies were able to confirm that extensive excavations at Fordow, a Revolutionary Guard base near the Shia theological centre of Qom, were a secret uranium enrichment plant under construction. The digging had been seen by satellites, but only human sources could identify its purpose. Barack Obama, Gordon Brown and Nicolas Sarkozy were able to reveal Fordow’s existence at the UN general assembly in September 2009, a diplomatic setback to Iran. Russia, which had been Iran’s principal protector on the world stage, was furious with Tehran at having been taken by surprise.

It is harder to gauge the impact of sabotage. Olli Heinonen, the former chief inspector of the International Atomic Energy Agency, said: “I never saw any direct evidence of sabotage. We could see that they had breakages but it was hard to say if those were the result of their own technical problems or sabotage. I suspect a little of both.”

Gholam Reza Aghazadeh, the head of Iran’s atomic energy organisation, complained to the press in 2006 about sabotage but vowed that Iran would overcome the challenge by making more of the centrifuges and other components itself.

But it was impossible to make everything at home. The computer systems which run the centrifuge operations in Natanz, supplied by the German engineering firm Siemens, were targeted last year by a computer worm called Stuxnet, reportedly created as a joint venture by US and Israeli intelligence. President Mahmoud Ahmadinejad conceded that Stuxnet had caused damage, and last November, Iranian scientists were forced to suspend enrichment to rectify the problem. A few days later, however, the centrifuges were working once more.

The black operations have not been confined to hardware and computer systems. They have also targeted Iran’s scientists. In July 2009, an Iranian nuclear expert called Shahram Amiri vanished while on a pilgrimage to Mecca. A year later, he surfaced in the US claiming he had been abducted by American agents, and in July 2010 he returned to a hero’s welcome in Tehran.

US officials said he had been a willing defector who had been paid $5m for his help, but who had since had a mysterious change of heart. There have since been claims Amiri had been an Iranian double agent all along. The truth is unclear.

Other attempts to remove Iran’s scientists have been blunter and bloodier.

Starting in January 2010, there were a series of attacks in Tehran on Iranian physicists with links to the nuclear programme. The first target was Masoud Ali Mohammadi, a physicist and lecturer at the Imam Hussein university, run by the Revolutionary Guards. He was on his way to work when a bomb fixed to a motorbike parked outside his house exploded and killed him instantly.

In November that year, assassins on motorbikes targeted two Iranian scientists simultaneously as they were stuck in morning traffic. In both cases, the killers drove up alongside their targets’ cars and stuck bombs to the side. Majid Shahriari, a scientist at the atomic energy organisation, who had co-authored a paper on neutron diffusion in a nuclear reactor, was killed.

The other target, Fereidoun Abbasi-Davani, suspected by western officials of being a central figure in experiments on building a nuclear warhead, was only injured. Three months later he was promoted to the leadership of the nuclear programme.

A third scientist, Darioush Rezaeinejad, was killed in an attack in July this year, when gunmen on motorbikes shot him in a street in east Tehran. He was initially described in the Iranian media as a “nuclear scientist”, but the government later denied he had any involvement in the programme.

Iran has blamed the attacks on the Israeli secret service, Mossad, and in August sentenced an Iranian, Majid Jamali-Fashi, to death for his alleged involvement in the Ali Mohammadi killing. He had confessed to being part of a hit-team trained in Israel, but it appeared likely he had made the confession under torture.

Despite the millions spent, stalled machines and deaths of leading scientists, Iran has steadily built up its stockpile of enriched uranium to 4.5 tonnes – enough for four nuclear bombs if it was further refined to weapons-grade purity. At most, the covert war has slowed the rate of progress, but it has not stopped it.

Graphene shows unusual thermoelectric response to light – MIT News Office.


Graphene shows unusual thermoelectric response to light

Finding could lead to new photodetectors or energy-harvesting devices.

Given the enormous scale of worldwide energy use, there are limited options for achieving significant reductions in greenhouse gas emissions.

October 20, 2011

Photo: Len Rubenstein

Graphene, an exotic form of carbon consisting of sheets a single atom thick, exhibits a novel reaction to light, MIT researchers have found: Sparked by light’s energy, the material can produce electric current in unusual ways. The finding could lead to improvements in photodetectors and night-vision systems, and possibly to a new approach to generating electricity from sunlight.

This current-generating effect had been observed before, but researchers had incorrectly assumed it was due to a photovoltaic effect, says Pablo Jarillo-Herrero, an assistant professor of physics at MIT and senior author of a new paper published in the journal Science. The paper’s lead author is postdoc Nathaniel Gabor; co-authors include four MIT students, MIT physics professor Leonid Levitov and two researchers at the National Institute for Materials Science in Tsukuba, Japan.

Instead, the MIT researchers found that shining light on a sheet of graphene, treated so that it had two regions with different electrical properties, creates a temperature difference that, in turn, generates a current. Graphene heats inconsistently when illuminated by a laser, Jarillo-Herrero and his colleagues found: The material’s electrons, which carry current, are heated by the light, but the lattice of carbon nuclei that forms graphene’s backbone remains cool. It’s this difference in temperature within the material that produces the flow of electricity. This mechanism, dubbed a “hot-carrier” response, “is very unusual,” Jarillo-Herrero says.

Such differential heating has been observed before, but only under very special circumstances: either at ultralow temperatures (measured in thousandths of a degree above absolute zero), or when materials are blasted with intense energy from a high-power laser. This response in graphene, by contrast, occurs across a broad range of temperatures all the way up to room temperature, and with light no more intense than ordinary sunlight.

The reason for this unusual thermal response, Jarillo-Herrero says, is that graphene is, pound for pound, the strongest material known. In most materials, superheated electrons would transfer energy to the lattice around them. In the case of graphene, however, that’s exceedingly hard to do, since the material’s strength means it takes very high energy to vibrate its lattice of carbon nuclei — so very little of the electrons’ heat is transferred to that lattice.

Because this phenomenon is so new, Jarillo-Herrero says it is hard to know what its ultimate applications might be. “Our work is mostly fundamental physics,” he says, but adds that “many people believe that graphene could be used for a whole variety of applications.”

But there are already some suggestions, he says: Graphene “could be a good photodetector” because it produces current in a different way than other materials used to detect light. It also “can detect over a very wide energy range,” Jarillo-Herrero says. For example, it works very well in infrared light, which can be difficult for other detectors to handle. That could make it an important component of devices from night-vision systems to advanced detectors for new astronomical telescopes.

The new work suggests graphene could also find uses in detection of biologically important molecules, such as toxins, disease vectors or food contaminants, many of which give off infrared light when illuminated. And graphene, made of pure and abundant carbon, could be a much cheaper detector material than presently used semiconductors that often include rare, expensive elements.

The research also suggests graphene could be a very effective material for collecting solar energy, Jarillo-Herrero says, because it responds to a broad range of wavelengths; typical photovoltaic materials are limited to specific frequencies, or colors, of light. But more research will be needed, he says, adding, “It is still unclear if it could be used for efficient energy generation. It’s too early to tell.”

“This is the absolute infancy of graphene photodetectors,” Jarillo-Herrero says. “There are many factors that could make it better or faster,” which will now be the subject of further research.

Philip Kim, an associate professor of physics at Columbia University who was not involved in this research, says the work represents “extremely important progress toward optoelectric and energy-harvesting applications” based on graphene. He adds that because of this team’s work, “we now have better understanding of photo-generated hot electrons in graphene, excited by light.”

The research was supported by the Air Force Office of Scientific Research, along with grants from the National Science Foundation and the Packard Foundation.

Whether you’re using wireless internet in a coffee shop, stealing it from the guy next door, or competing for bandwidth at a conference, you’ve probably gotten frustrated at the slow speeds you face when more than one device is tapped into the network. As more and more people—and their many devices—access wireless internet, clogged airwaves are going to make it increasingly difficult to latch onto a reliable signal.

But radio waves are just one part of the spectrum that can carry our data. What if we could use other waves to surf the internet?

One German physicist, Harald Haas, has come up with a solution he calls “data through illumination”—taking the fiber out of fiber optics by sending data through an LED lightbulb that varies in intensity faster than the human eye can follow. It’s the same idea behind infrared remote controls, but far more powerful.

Haas says his invention, which he calls D-Light, can produce data rates faster than 10 megabits per second, which is speedier than your average broadband connection. He envisions a future where data for laptops, smartphones, and tablets is transmitted through the light in a room. And security would be a snap—if you can’t see the light, you can’t access the data.

You can imagine all kinds of uses for this technology, from public internet access through street lamps to auto-piloted cars that communicate through their headlights. And more data coming through the visible spectrum could help alleviate concerns that the electromagnetic waves that come with WiFi could adversely affect your health. Talk about the bright side.

New battery design could give electric vehicles a jolt.

New battery design could give electric vehicles a jolt

Significant advance in battery architecture could be breakthrough for electric vehicles and grid storage.

A sample of ‘Cambridge crude’ — a black, gooey substance that can power a highly efficient new type of battery. A prototype of the semi-solid flow battery is seen behind the flask.
Photo: Dominick Reuter June 6, 2011
A radically new approach to the design of batteries, developed by researchers at MIT, could provide a lightweight and inexpensive alternative to existing batteries for electric vehicles and the power grid. The technology could even make “refueling” such batteries as quick and easy as pumping gas into a conventional car.

The new battery relies on an innovative architecture called a semi-solid flow cell, in which solid particles are suspended in a carrier liquid and pumped through the system. In this design, the battery’s active components — the positive and negative electrodes, or cathodes and anodes — are composed of particles suspended in a liquid electrolyte. These two different suspensions are pumped through systems separated by a filter, such as a thin porous membrane.

The work was carried out by Mihai Duduta ’10 and graduate student Bryan Ho, under the leadership of professors of materials science W. Craig Carter and Yet-Ming Chiang. It is described in a paper published May 20 in the journal Advanced Energy Materials. The paper was co-authored by visiting research scientist Pimpa Limthongkul ’02, postdoc Vanessa Wood ’10 and graduate student Victor Brunini ’08.

One important characteristic of the new design is that it separates the two functions of the battery — storing energy until it is needed, and discharging that energy when it needs to be used — into separate physical structures. (In conventional batteries, the storage and discharge both take place in the same structure.) Separating these functions means that batteries can be designed more efficiently, Chiang says.

The new design should make it possible to reduce the size and the cost of a complete battery system, including all of its structural support and connectors, to about half the current levels. That dramatic reduction could be the key to making electric vehicles fully competitive with conventional gas- or diesel-powered vehicles, the researchers say.

Another potential advantage is that in vehicle applications, such a system would permit the possibility of simply “refueling” the battery by pumping out the liquid slurry and pumping in a fresh, fully charged replacement, or by swapping out the tanks like tires at a pit stop, while still preserving the option of simply recharging the existing material when time permits.

Flow batteries have existed for some time, but have used liquids with very low energy density (the amount of energy that can be stored in a given volume). Because of this, existing flow batteries take up much more space than fuel cells and require rapid pumping of their fluid, further reducing their efficiency.

The new semi-solid flow batteries pioneered by Chiang and colleagues overcome this limitation, providing a 10-fold improvement in energy density over present liquid flow-batteries, and lower-cost manufacturing than conventional lithium-ion batteries. Because the material has such a high energy density, it does not need to be pumped rapidly to deliver its power. “It kind of oozes,” Chiang says. Because the suspensions look and flow like black goo and could end up used in place of petroleum for transportation, Carter says, “We call it ‘Cambridge crude.’”

The key insight by Chiang’s team was that it would be possible to combine the basic structure of aqueous-flow batteries with the proven chemistry of lithium-ion batteries by reducing the batteries’ solid materials to tiny particles that could be carried in a liquid suspension — similar to the way quicksand can flow like a liquid even though it consists mostly of solid particles. “We’re using two proven technologies, and putting them together,” Carter says.

In addition to potential applications in vehicles, the new battery system could be scaled up to very large sizes at low cost. This would make it particularly well-suited for large-scale electricity storage for utilities, potentially making intermittent, unpredictable sources such as wind and solar energy practical for powering the electric grid.

The team set out to “reinvent the rechargeable battery,” Chiang says. But the device they came up with is potentially a whole family of new battery systems, because it’s a design architecture that “is not linked to any particular chemistry.” Chiang and his colleagues are now exploring different chemical combinations that could be used within the semi-solid flow system. “We’ll figure out what can be practically developed today,” Chiang says, “but as better materials come along, we can adapt them to this architecture.”

Yury Gogotsi, Distinguished University Professor at Drexel University and director of Drexel’s Nanotechnology Institute, says, “The demonstration of a semi-solid lithium-ion battery is a major breakthrough that shows that slurry-type active materials can be used for storing electrical energy.” This advance, he says, “has tremendous importance for the future of energy production and storage.”

Gogotsi cautions that making a practical, commercial version of such a battery will require research to find better cathode and anode materials and electrolytes, but adds, “I don’t see fundamental problems that cannot be addressed — those are primarily engineering issues. Of course, developing working systems that can compete with currently available batteries in terms of cost and performance may take years.”

Chiang, whose earlier insights on lithium-ion battery chemistries led to the 2001 founding of MIT spinoff A123 Systems, says the two technologies are complementary, and address different potential applications. For example, the new semi-solid flow batteries will probably never be suitable for smaller applications such as tools, or where short bursts of very high power are required — areas where A123’s batteries excel.

The new technology is being licensed to a company called 24M Technologies, founded last summer by Chiang and Carter along with entrepreneur Throop Wilder, who is the company’s president. The company has already raised more than $16 million in venture capital and federal research financing.

The development of the technology was partly funded by grants from the U.S. Department of Defense’s Defense Advanced Research Projects Agency and Advanced Research Projects Agency – Energy (ARPA-E). Continuing research on the technology is taking place partly at 24M, where some recent MIT graduates who worked on the project are part of the team; at MIT, where professors Angela Belcher and Paula Hammond are co-investigators; and at Rutgers, with Professor Glenn Amatucci.

The target of the team’s ongoing work, under a three-year ARPA-E grant awarded in September 2010, is to have, by the end of the grant period, “a fully-functioning, reduced-scale prototype system,” Chiang says, ready to be engineered for production as a replacement for existing electric-car batteries.