Professor Jorge Rocca offer a new path to creating the extreme conditions found in stars, using ultra-short laser pulses irradiating nanowires

Representation of the creation of ultra-high energy density matter by an intense laser pulse irradiation of an array of aligned nanowires. Credit: R. Hollinger and A. Beardall

The energy density contained in the center of a star is higher than we can imagine -- many billions of atmospheres, compared with the 1 atmosphere of pressure we live with here on Earth's surface.

These extreme conditions can only be recreated in the laboratory through fusion experiments with the world's largest lasers, which are the size of stadiums. Now, scientists have conducted an experiment at Colorado State University that offers a new path to creating such extreme conditions, with much smaller, compact lasers that use ultra-short laser pulses irradiating arrays of aligned nanowires.

The experiments, led by University Distinguished Professor Jorge Rocca in the Departments of Electrical and Computer Engineering and Physics, accurately measured how deeply these extreme energies penetrate the nanostructures. These measurements were made by monitoring the characteristic X-rays emitted from the nanowire array, in which the material composition changes with depth.

HPLSE editorial tribute to Professor David Neely

OPN Talks with Jorge Rocca photo: Optics & Photonics News

Numerical models validated by the experiments predict that increasing irradiation intensities to the highest levels made possible by today's ultrafast lasers could generate pressures to surpass those in the center of our sun.

J. J. Rocca's research works Colorado State ResearchGate

The results, published Jan. 11 in the journal Science Advances, open a path to obtaining unprecedented pressures in the laboratory with compact lasers. The work could open new inquiry into high energy density physics; how highly charged atoms behave in dense plasmas; and how light propagates at ultrahigh pressures, temperatures, and densities.

Creating matter in the ultra-high energy density regime could inform the study of laser-driven fusion -- using lasers to drive controlled nuclear fusion reactions -- and to further understanding of atomic processes in astrophysical and extreme laboratory environments.

A strategy to achieve ultrahigh power and energy density in lithium-ion batteries Tech Xplore

The ability to create ultra-high energy density matter using smaller facilities is thus of great interest for making these extreme plasma regimes more accessible for fundamental studies and applications. One such application is the efficient conversion of optical laser light into bright flashes of X-rays.

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The above post is reprinted from materials provided by Sciencedaily. Note: Materials may be edited for content and length.

2017 in Review: NASA’s Space Technology Mission Directorate (STMD) Pioneering Progress

Solar Electric Propulsion work is underway, sponsored by NASA's Space Technology Mission Directorate and managed by NASA's Glenn Research Center. A prototype 13-kilowatt Hall thruster, shown here, is tested to demonstrate the technology readiness needed for industry to continue the development of high-power solar electric propulsion into a flight-qualified system. Credits: NASA

NASA’s Space Technology Mission Directorate (STMD) is dedicated to pushing the technological envelope, taking on challenges not only to further space agency missions near Earth, but also to sustain future deep space exploration activities.

“In 2016, we completed several major program milestones,” explains Steve Jurczyk, NASA associate administrator for STMD.

During the year, STMD focused upon and made significant progress in advancing technologies and capabilities in the following areas:

Space Power and Propulsion;

• High-Bandwidth Communications, Deep Space Navigation, Avionics;
• Advanced Life Support and Resource Utilization;
• Entry, Descent and Landing Systems;
• Autonomy and Space Robotic Systems;
• Lightweight Structures and Manufacturing;
• Space Observatory Systems

Enabling engine 

Jurczyk points to areas of notable progress in fiscal year 2016, particularly work on high-power Solar Electric Propulsion (SEP) – an enabler for cost-effective deep space exploration.

Asteroid Redirect Mission makes use of solar electric propulsion. The vehicle’s solar arrays collect power from the sun and convert it to energy to ionize and accelerate xenon propellant, resulting in the bright blue plume at the rear of the vehicle. Credits: NASA

SEP makes use of large solar cell arrays that convert collected sunlight energy to electrical power. That energy is fed into extremely fuel-efficient thrusters that provide gentle but nonstop thrust throughout the mission. SEP thrusters are designed to use far less propellant than comparable, conventional chemical propulsion systems.

“We completed the development and testing of a prototype SEP engine at NASA’s Glenn Research Center. Also, we have contracted with Aerojet Rocketdyne to develop the SEP flight system for the Asteroid Redirect Robotic Mission,” Jurczyk notes.

Furthermore, SEP solar array technology is being transitioned into commercial application, Jurczyk adds, by both Space Systems Loral and Orbital ATK.

Green propellant 

Another 2016 spotlight on progress, Jurczyk observes, is the integration and testing of the Green Propellant Infusion Mission (GPIM). Now ready for launch in 2017, GPIM will test the distinctive quality of a high-performance, non-toxic, “green” fuel in orbit.

STMD worked with Aerojet Rocketdyne in Redmond, Washington and GPIM prime contractor Ball Aerospace & Technologies Corp. in Boulder, Colorado, to develop the spacecraft capable of using the unique propellant. It will fly on the U.S. Air Force’s Space Test Program (STP-2) mission.

Given the term “green” propellant, Jurczyk points out that the Air Force-developed fuel is a hydroxyl ammonium nitrate-based fuel/oxidizer mix, also known as AF-M315E. GPIM will flight demonstrate this fuel designed to replace use of highly toxic hydrazine and complex bi-propellant systems now in common use today.

“GPIM’s green propellant is less toxic than hydrazine. It will reduce spacecraft processing costs and it has 40 percent higher performance by volume than hydrazine,” Jurczyk says.

Aerojet Rocketdyne, builder of GPIM’s set of thrusters, is now marketing the novel thrusters as a product. The aerospace firm is also working with NASA’s Glenn Research Center to further enhance the thrusters, looking to reduce cost and add to their reliability, Jurczyk adds. “So we’re collaborating with the aerospace company to further advance this technology and I’m pleased with the progress.”

Push the technology 

Jurczyk reports that STMD-supported work on the Deep Space Atomic Clock, DSAC for short, is ongoing.

DSAC is a small, low-mass atomic clock based on mercury-ion trap technology that will be demonstrated in space, providing unprecedented stability needed for next-generation deep space navigation and radio science. NASA’s Jet Propulsion Laboratory oversees project development of DSAC, which offers the promise of 50 times more accuracy than today’s best navigation clocks.

STMD’s Flight Opportunities program includes use of Masten Space Systems’ XA-0.1B “Xombie” vertical-launch, vertical-landing reusable rocket as a risk-reduction activity, testing science experiments and hardware before long duration spaceflight. Vehicle is shown soaring above Mojave Air and Space Port in California. Credits: NASA Photo/Tom Tschida

The task of designing DSAC has not been trouble-free, but it represents a tenant of STMD “to push the technology,” Jurczyk responds. Taking on the challenges of space-rating terrestrial based atomic clock technology is not easy. However, the path forward has been outlined with launch of DSAC now eyed for next year.

The DSAC demonstration unit and payload is to be hosted on a spacecraft provided by Surrey Satellite Technologies U.S. of Englewood, Colorado, lofted spaceward as part of the U.S. Air Force Space Test Program 2 mission aboard a Space X Falcon 9 Heavy booster.

Tipping point partnerships 

In 2016, STMD entered into their first set of public-private partnerships, a solicitation that proved very beneficial – to both industry and NASA. Called “Utilizing Public-Private Partnerships to Advance Tipping Point Technologies,” Jurczyk is pleased with this facilitated collaborative effort with industry. These partnerships require companies to contribute at least 25 percent of the funding; NASA contributes up to $20 million for ground-based efforts.

With the recent increase of the U.S. private sector interest in space applications, NASA is seeking commercial space technologies that are at a “tipping point” in their development.

“We do many one-on-one discussions with companies about their interests. For NASA, we want to help advance technologies that boost commercial products and services,” he points out. The Tipping Point partnerships have led to contracts, for example, in space robotic manufacturing and small spacecraft technologies.

Similarly, Jurczyk adds that in 2016, STMD saw collaborative opportunity for industry to tap into NASA expertise, allowing companies to use space agency talent and facilities. This collaboration is made possible through non-reimbursable, no-exchange-of-funds Space Act Agreements. Those types of agreements, he emphasizes, have enabled private-sector advancements in technologies such as small launch vehicle rocket engines and advanced structures for small boosters.

Flight opportunities

“It has been a good and productive year for STMD’s Flight Opportunities program,” Jurczyk advises.

That program provides affordable access to relevant space-like environments for NASA payloads. This activity makes use of a variety of flight platforms, such as Blue Origin’s New Shepard suborbital vehicle, Masten Space Systems’ XA-0.1B “Xombie” vertical-launch, vertical-landing reusable rocket, as well as the UP Aerospace SpaceLoft sounding rocket.

STMD’s lineup of smallsat launches in 2017 includes the CubeSat Proximity Operations Demonstration (CPOD) project that will demonstrate rendezvous, proximity operations and docking using two CubeSats. Credits: NASA/Ames/Tyvak Nano-Satellite Systems, Inc.

“We can ‘ring out’ experiments and technologies in short duration exposure to relevant flight conditions before they go onto longer duration flight on space missions,” Jurczyk explains. “It’s a risk reduction activity,” he continues, for example, in life science research or shaking out various robotic technologies.

Big year ahead 

Looking into 2017, STMD’s Jurczyk highlights the launch of the Green Propellant Infusion Mission and the Deep Space Atomic Clock. “Those are two major flight demonstrations and are very important.”

Among a host of STMD-supported activities, next year will see flight of small satellites to showcase, for instance, optical laser communications. Then there’s the Integrated Solar Array and Reflectarray Antenna (ISARA) for advanced communications and the CubeSat Proximity Operations Demonstration (CPOD). The function of CPOD is to trial-run autonomous rendezvous and docking, Jurczyk says.

“There’s going to be a lot going on,” Jurczyk concludes. “It’ll be a big year for small satellites and space technology.”

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The above post is reprinted from materials provided by NASA. Note: Materials may be edited for content and length.

A big step in to the future: The first solar street in the world. VIDEO

The world's first solar street was commissioned in the province of Normandy in north-eastern France.

One kilometer of road was paved with solid solar panels  (2,800 square meters of solar tiles) that produce energy.

Photovoltaic panels were glued on a stretch of one kilometer and should generate energy for public lighting of a small town with about 5,000 inhabitants.

The cost of solar street is 5 million, being borne entirely by the French State. One such project was opened in the Netherlands, where a bicycle track produce energy.


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• The smallest nuclear power plant in the world. Only 6 meters long and heat 500,000 homes.

The smallest nuclear power plant in the world. Only 6 meters long and heat 500,000 homes.

China builds the smallest nuclear power plant in the world that will be used over 5 years

This plant will be inside a shipping container and can generate 10 megawatts of heat, enough to cover the needs of 500,000 homes. It will be placed in future on a platform in the South China Sea. Known as Hedianbao or nuclear battery portable small power plant measured 6.1 meters 2.6 meters. It can work for several decades until you have refueled. Moreover, it may be used to desalinate large quantities of water which subsequently can be used as fresh water.

However, there is a risk that some of the incidents to cause a release of nuclear power, which may be catastrophic, and the temperature of the sea water in which it will be placed to increase. However, researchers are trying to convince the population that it is extremely safe.


Source:  Daily Mail

Scientists convert carbon dioxide to create electricity

This graphic explains novel method for capturing the greenhouse gas and converting it to a useful product -- while producing electrical energy.
Credit: Cornell University

While the human race will always leave its carbon footprint on the Earth, it must continue to find ways to lessen the impact of its fossil fuel consumption.

"Carbon capture" technologies -- chemically trapping carbon dioxide before it is released into the atmosphere -- is one approach. In a recent study, Cornell University researchers disclose a novel method for capturing the greenhouse gas and converting it to a useful product -- while producing electrical energy.

System to convert carbon dioxide into electricity and hydrogen source: Computing

Lynden Archer, the James A. Friend Family Distinguished Professor of Engineering, and doctoral student Wajdi Al Sadat have developed an oxygen-assisted aluminum/carbon dioxide power cell that uses electrochemical reactions to both sequester the carbon dioxide and produce electricity.

Their paper, "The O2-assisted Al/CO2 electrochemical cell: A system for CO2 capture/conversion and electric power generation," was published July 20 in Science Advances.


The group's proposed cell would use aluminum as the anode and mixed streams of carbon dioxide and oxygen as the active ingredients of the cathode. The electrochemical reactions between the anode and the cathode would sequester the carbon dioxide into carbon-rich compounds while also producing electricity and a valuable oxalate as a byproduct.

In most current carbon-capture models, the carbon is captured in fluids or solids, which are then heated or depressurized to release the carbon dioxide. The concentrated gas must then be compressed and transported to industries able to reuse it, or sequestered underground. The findings in the study represent a possible paradigm shift, Archer said.

Carbon sequestration - Wikipedia

"The fact that we've designed a carbon capture technology that also generates electricity is, in and of itself, important," he said. "One of the roadblocks to adopting current carbon dioxide capture technology in electric power plants is that the regeneration of the fluids used for capturing carbon dioxide utilize as much as 25 percent of the energy output of the plant. This seriously limits commercial viability of such technology. Additionally, the captured carbon dioxide must be transported to sites where it can be sequestered or reused, which requires new infrastructure."

The group reported that their electrochemical cell generated 13 ampere hours per gram of porous carbon (as the cathode) at a discharge potential of around 1.4 volts. The energy produced by the cell is comparable to that produced by the highest energy-density battery systems.

Another key aspect of their findings, Archer says, is in the generation of superoxide intermediates, which are formed when the dioxide is reduced at the cathode. The superoxide reacts with the normally inert carbon dioxide, forming a carbon-carbon oxalate that is widely used in many industries, including pharmaceutical, fiber and metal smelting.

Carnegie Climate Governance Initiative Infographic: Let's Ask the Big Questions on the Governance

"A process able to convert carbon dioxide into a more reactive molecule such as an oxalate that contains two carbons opens up a cascade of reaction processes that can be used to synthesize a variety of products," Archer said, noting that the configuration of the electrochemical cell will be dependent on the product one chooses to make from the oxalate.

Al Sadat, who worked on onboard carbon capture vehicles at Saudi Aramco, said this technology in not limited to power-plant applications. "It fits really well with onboard capture in vehicles," he said, "especially if you think of an internal combustion engine and an auxiliary system that relies on electrical power."

He said aluminum is the perfect anode for this cell, as it is plentiful, safer than other high-energy density metals and lower in cost than other potential materials (lithium, sodium) while having comparable energy density to lithium. He added that many aluminum plants are already incorporating some sort of power-generation facility into their operations, so this technology could assist in both power generation and reducing carbon emissions.


A current drawback of this technology is that the electrolyte -- the liquid connecting the anode to the cathode -- is extremely sensitive to water. Ongoing work is addressing the performance of electrochemical systems and the use of electrolytes that are less water-sensitive.

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The above post is reprinted from materials provided by Cornell University. The original item was written by Melissa Osgood. Note: Materials may be edited for content and length.

MIT researchers have invented a revolutionary technology batteries

Test for a long time, lithium-air battery technology provides a high energy density storage of Li-ion batteries used today, but they have several drawbacks that lithium-oxygen technology developed by MIT researchers promises to solve the institute.

Using oxygen from the air as a catalyst in chemical processes that occur during the operation of loading / unloading battery Li-air end up wasting a good deal of energy to 30% of the electricity received from AC power is converted directly into heat.


If batteries with Li-oxygen technology, the same chemical reactions occur but without direct contact with atmospheric air, replaced by a series of chemical compounds - Li2O, Li2O2 and LiO2 - which remain permanently in the solid state.

With less waste heat released during charging Li-air batteries can reach the desired capacity in a shorter time, while making it easier to use them in large numbers - for example to power electric vehicles.

According to the team led by a researcher named Ju Li, the chemical processes that occur during this type of battery charging protects against accidental overloading, chemical reactions going on to form inert after reaching maximum capacity energy storage.

For comparison, Li-ion battery technology can be damaged by overheating quickly, with even a fire hazard if the power supply is not disconnected at the time.




Source: Go4it

Future batteries will change everything (ultimate' battery)

Many of the technologies we use every day have been getting smaller, faster and cheaper each year -- with the notable exception of batteries. Apart from the possibility of a smartphone which lasts for days without needing to be charged, the challenges associated with making a better battery are holding back the widespread adoption of two major clean technologies: electric cars and grid-scale storage for solar power.


Scientists have developed a working laboratory demonstrator of a lithium-oxygen battery which has very high energy density, is more than 90% efficient, and, to date, can be recharged more than 2000 times, showing how several of the problems holding back the development of these devices could be solved.

However, as is the case with other next-generation batteries, there are several practical challenges that need to be addressed before lithium-air batteries become a viable alternative to gasoline.

Now, researchers from the University of Cambridge have demonstrated how some of these obstacles may be overcome, and developed a lab-based demonstrator of a lithium-oxygen battery which has higher capacity, increased energy efficiency and improved stability over previous attempts.

Their demonstrator relies on a highly porous, 'fluffy' carbon electrode made from graphene (comprising one-atom-thick sheets of carbon atoms), and additives that alter the chemical reactions at work in the battery, making it more stable and more efficient. While the results, reported in the journal Science, are promising, the researchers caution that a practical lithium-air battery still remains at least a decade away.

"What we've achieved is a significant advance for this technology and suggests whole new areas for research -- we haven't solved all the problems inherent to this chemistry, but our results do show routes forward towards a practical device," said Professor Clare Grey of Cambridge's Department of Chemistry, the paper's senior author.

Many of the technologies we use every day have been getting smaller, faster and cheaper each year -- with the notable exception of batteries. Apart from the possibility of a smartphone which lasts for days without needing to be charged, the challenges associated with making a better battery are holding back the widespread adoption of two major clean technologies: electric cars and grid-scale storage for solar power.

"In their simplest form, batteries are made of three components: a positive electrode, a negative electrode and an electrolyte,'' said Dr Tao Liu, also from the Department of Chemistry, and the paper's first author.

In the lithium-ion (Li-ion) batteries we use in our laptops and smartphones, the negative electrode is made of graphite (a form of carbon), the positive electrode is made of a metal oxide, such as lithium cobalt oxide, and the electrolyte is a lithium salt dissolved in an organic solvent. The action of the battery depends on the movement of lithium ions between the electrodes. Li-ion batteries are light, but their capacity deteriorates with age, and their relatively low energy densities mean that they need to be recharged frequently.

Over the past decade, researchers have been developing various alternatives to Li-ion batteries, and lithium-air batteries are considered the ultimate in next-generation energy storage, because of their extremely high energy density. However, previous attempts at working demonstrators have had low efficiency, poor rate performance, unwanted chemical reactions, and can only be cycled in pure oxygen.

What Liu, Grey and their colleagues have developed uses a very different chemistry than earlier attempts at a non-aqueous lithium-air battery, relying on lithium hydroxide (LiOH) instead of lithium peroxide (Li2O2). With the addition of water and the use of lithium iodide as a 'mediator', their battery showed far less of the chemical reactions which can cause cells to die, making it far more stable after multiple charge and discharge cycles.

By precisely engineering the structure of the electrode, changing it to a highly porous form of graphene, adding lithium iodide, and changing the chemical makeup of the electrolyte, the researchers were able to reduce the 'voltage gap' between charge and discharge to 0.2 volts. A small voltage gap equals a more efficient battery -- previous versions of a lithium-air battery have only managed to get the gap down to 0.5 -- 1.0 volts, whereas 0.2 volts is closer to that of a Li-ion battery, and equates to an energy efficiency of 93%.


The highly porous graphene electrode also greatly increases the capacity of the demonstrator, although only at certain rates of charge and discharge. Other issues that still have to be addressed include finding a way to protect the metal electrode so that it doesn't form spindly lithium metal fibres known as dendrites, which can cause batteries to explode if they grow too much and short-circuit the battery.

Additionally, the demonstrator can only be cycled in pure oxygen, while the air around us also contains carbon dioxide, nitrogen and moisture, all of which are generally harmful to the metal electrode.

"There's still a lot of work to do," said Liu. "But what we've seen here suggests that there are ways to solve these problems -- maybe we've just got to look at things a little differently."

"While there are still plenty of fundamental studies that remain to be done, to iron out some of the mechanistic details, the current results are extremely exciting -- we are still very much at the development stage, but we've shown that there are solutions to some of the tough problems associated with this technology," said Grey.

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• The smallest nuclear power plant in the world. Only 6 meters long and heat 500,000 homes.

• MIT researchers have invented a revolutionary technology batteries

• A big step in to the future: The first solar street in the world. VIDEO

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The above post is reprinted from materials provided by University of Cambridge. Note: Materials may be edited for content and length.