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The Fruits of Their Labors...

Posted by Reginald L. Goodwin on May 17, 2018 at 7:51am

Topics: Civics, Commentary, Existentialism, Research

It has finally happened. The inevitable was likely to come. As we've celebrated stupidity as a virtue (hell, we somehow let a foreign power put an imbecile with the attention span of a gnat, and has taken pathological lying to Olympic levels in charge of the nuclear codes), it was most assuredly going to be reflected in the data:

The US’s dominance in scooping Nobel prizes for work in the natural sciences could be nearing an end, according to a new analysis of previous winners. Carried out by physicist Claudius Gros from the Goethe University in Frankfurt, Germany, it also finds that the UK has won the most Nobel prizes per capita, with Germany coming second and the US a close third (R. Soc. Open Sci. 5 180167).

Since they were first awarded in 1901, scientists who are nationals of the US, the UK, Germany and France have won the most Nobel prizes in physics, chemistry, and physiology or medicine. Around 120 laureates have been American, 40 British, 40 German and 20 French. To determine Nobel-prize productivity, however, Gros factored out population size, particularly given that the US population has more than quadrupled from 76 million in 1901 to 327 million today.

Of course, the laborers will deny it, pious and humble in their efforts to denigrate science, scandalize research, question reality, facts, data: try to morally equivocate between evolution and (not) "intelligent design." We have been on this anti-intellectual Primrose Path since the Scopes Monkey trials. A select segment of the species here in America made denial of facts a staple of membership to the cult, and find they have a political voice in a bipolar tweeting, carnival-barking avatar. As Dr. Gros continues:

Gros found that the US’s productivity peaked in 1972 at 0.83 Nobel prizes per year and per 100 million inhabitants. He says that the most striking element of the US data is the continued downward trend. Since 1972 its success rate has fallen by 60% to 0.34 Nobel prizes per year and per 100 million inhabitants, and it is still dropping. “On a per capita basis, the US’s era is definitively coming to an end,” Gros told Physics World. “Within 12 years the US science Nobel prizes productivity should fall by another 50%.”

That will put us down to 0.17 per 100 million inhabitants by 2030, when the population should be: 327,000,000*e^(0.02*18) = 468,698,719 (from the Growth Formula: N = N_0*e^rt, r = growth/death rate of 0.02, t = time).

That's going to be a lot of mouths to feed and employ with fewer and fewer minds to generate new ideas, industries and thus, employment of the masses. Our slide from "exceptionalism" will inevitably follow.

Is the end in sight for US Nobel prize dominance? Culture, History and Society

Michael Allen, Physics World, Bristol, UK

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58 Years to the Blue Ray...

Posted by Reginald L. Goodwin on May 16, 2018 at 9:54am
Bright prospect: the first International Day of Light will be celebrated on 16 May. (Courtesy: iStock/RichLegg)

Topics: Applied Physics, Laser, Optical Physics, Photonics

This month sees the first International Day of Light. Wednesday 16 May was chosen because it is the anniversary of the first successful operation of the laser, as demonstrated by the American engineer and physicist Ted Maiman in 1960.

It’s a good choice, because the laser is a perfect example of how a scientific discovery can yield revolutionary benefits to society in all sorts of areas, including communications, healthcare and manufacturing. However, when I read the words “first successful operation of the laser” on the International Day of Light website (lightday.org), I had to look further, as it sounded like there might be more to the story.

I have spent most of my career working in photonics, optical communications and lighting, so I was already somewhat familiar with the laser’s history. However, the details still interested me. It turns out that although Maiman did indeed demonstrate the first working laser on 16 May 1960, he is not the only person with a reasonable claim to have “invented” the laser. The other is Gordon Gould, another US physicist who described “Some rough calculations on the feasibility of a LASER: Light Amplification by Stimulated Emission of Radiation” in his lab notebook in November 1957.

A day of light, James McKenzie, Physics World

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A Clash of Theories...

Posted by Reginald L. Goodwin on May 15, 2018 at 8:04am
Each universe in a multiverse contains different levels of dark energy, according to the dominant theory. STOLK/GETTY IMAGES

Topics: Astrophysics, Cosmology, Dark Energy, Multiverses, Theoretical Physics

A hypothetical multiverse seems less likely after modeling by researchers in Australia and the UK threw one of its key assumptions into doubt.

The multiverse concept suggests that our universe is but one of many. It finds support among some of the world’s most accomplished physicists, including Brian Greene, Max Tegmark, Neil deGrasse Tyson and the late Stephen Hawking.

One of the prime attractions of the idea is that it potentially accounts for an anomaly in calculations for dark energy.

The mysterious force is thought to be responsible for the accelerating expansion of our own universe. Current theories, however, predict there should be rather more of it around than there appears to be. This throws up another set of problems: if the amount of dark energy around was as much as equations require – and that is many trillions of times the level that seems to exist – the universe would expand so rapidly that stars and planets would not form – and life, thus, would not be possible.

The multiverse idea to an extent accounts for and accommodates this oddly small – but life-permitting – dark energy quotient. Essentially it permits a curiously self-serving explanation: there are a vast number of universes all with differing amounts of dark energy. We exist in one that has an amount low enough to permit stars and so on to form, and thus life to exist. (And we find ourselves here, runs the logic, because we couldn’t find ourselves anywhere else.)

So far, so anthropic. But now a group of astronomers, including Luke Barnes from the University of Sydney in Australia and Jaime Salcido from Durham University in the UK, has published two papers in the journal Monthly Notices of the Royal Astronomical Society that show the dark energy and star formation balance isn’t quite as fine as previous estimates have suggested.

Multiverse theory cops a blow after dark energy findings

Andrew Masterson, Cosmos Magazine

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Induced Seismicity...

Posted by Reginald L. Goodwin on May 14, 2018 at 8:07am
Mechanisms of induced seismicity Both wastewater injection and gas extraction can cause induced earthquakes. Detailed observations from the Midwestern United States and Groningen, Netherlands, show that in both cases, preexisting conditions in Earth's crust are of central importance

Topics: Alternative Energy, Earthquake, Geophysics, Green Energy

Since 2009, the Midwestern United States has seen a dramatic rise in earthquakes induced by human activities. Most of these events were caused by massive reinjection of wastewater produced during oil and gas extraction (1, 2). In February 2016, regulators in Oklahoma called for an injection rate reduction after several major events up to moment magnitude 5.8 (Mw 5.8) occurred. On the other side of the Atlantic, an unprecedented number of earthquakes has followed gas extraction from the Groningen field in the Netherlands (3). The Dutch government imposed production cuts after a Mw 3.6 event in August 2012 caused structural damage to houses. Intensive research of these two instances of induced seismicity points to contrasting mechanisms, but in both cases, the natural conditions prior to subsurface activities play a dominant part.

Fifty years ago, Healy et al. determined that fluid injection at depth causes the pore pressure to rise in a preexisting fault, reducing its strength and potentially leading to its failure (4). In contrast, fluid extraction at depth reduces the pore pressure, leading to compaction of the rock mass; the increased rock stress can drive a preexisting fault to failure. In both settings, the two factors that control induced earthquakes are operational parameters, such as the volume that is injected or produced, and natural conditions, such as the presence of preexisting faults and their ambient stress level. Operational parameters are often assumed to dominate, but that notion may reflect limited knowledge of the locations of preexisting faults and their ambient stress level. For regulatory measures to be effective in mitigating induced seismicity, it is crucial to understand the role of the natural conditions that existed before human activities.

How earthquakes are induced

Thibault Candela, Brecht Wassing, Jan ter Heege, Loes Buijze

Science

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Replicators and Mosaddegh...

Posted by Reginald L. Goodwin on May 11, 2018 at 7:30am
Mosaddegh shaking hands with Mohammad-Reza Shah in their first meeting after Mossadegh's election as Prime Minister By Unknown - http://www.aryamehr.org/eng/19august/28mordad.htm, Public Domain, https://commons.wikimedia.org/w/index.php?curid=7431651

Topics: Commentary, Existentialism, Politics, Star Trek

Star Trek (to me) is a societal metaphor for the perfection we at least see ourselves as a species eventually achieving in civics, equality and technology, an update to Winthrop's "city on a hill." A lot of the scripted claims aren't supported by any known science, the term "technobabble" is now a part of the lexicon. I gave up one night at Motorola trying to explain to a coworker the sound barrier is a lot different than a "light speed barrier" due to the fact we're all composed of matter, which has mass and thus, drag. Some things you just have to let go of.

I do often ask the question in casual Trek conversations: "In the fictional Star Trek universe, what is the most impacting technology?" If you're a Worf-type, it's phasers; if you're a Riker-type, it's warp drive (see my exasperation in the paragraph above).

But no, in this fantastical universe where I'm surprised they haven't yet pulled off a Star Trek/Star Wars crossover, I'd say the technology with the most impact has to be...replicators, those wretched violators of the Heisenberg Uncertainty Principle, right along with transporters that reassemble you just like you started, versus cloning ever-imperfect facsimiles as the physics should work. (See: Jeff Goldblum in The Fly)

The closest thing we have to replicators is 3D printing. Maybe combining that with a phone app would be a facsimile of the classic Picard line: tea, Earl Grey...hot! I know that sounds a lot like Panera Bread...

Wages have been stagnant since the seventies, exacerbating income inequality and leading to not just two Americas, but two societies: one rich, one poor and no middle class bridge in-between. It is a recipe for dystopia. Replicators would be a disturbing disruption to the hierarchical status quo. Suddenly, workers wouldn't have to "work" to feed themselves or their families. Industries would be short of workers that essentially stopped showing up for the Prussian economic model of capitalism. It would scare the piss out of the 1%! They might try to convince everyone of the "dangers" like Edison did AC current by electrocuting an elephant. However, someone's likely to leak the plans to the Internet, then all bets would be off. It would be a middle finger from the Proletariat. It's pure fantasy, but it would essentially eliminate the need for money, economy and thus hierarchies and control of societal "pariahs," which seems - among other things - a consistent critique from the right regarding the Trek franchise. 

*****

Mohammad Mosaddegh was the democratically elected leader of Iran. In 1953, oil interests in the United States and United Kingdom orchestrated a coup d'état primarily for the company now known as British Petroleum (BP). The operation was orchestrated by the Central Intelligence Agency (as new CIA Chief Gina Haspel would opine, "the good guys") and its manipulating British counterpart, MI-6. We then installed the Shah of Iran, by all accounts a brutal dictator that assassinated his enemies until the uprising that started my senior year in high school and solidified the rise of Ronald Reagan, who said to his admirers "our best days are behind us," almost in the same breath as announcing his presidential run blocks away from the site where three Civil Rights workers Michael Schwerner, James Chaney and Andrew Goodman were murdered in Philadelphia, Mississippi. That eventually had to morph into another slogan born of bigotry, birtherism, jealousy and xenophobia: "make America great again."

From Wikipedia: "An author, administrator, lawyer, and prominent parliamentarian, his administration introduced a range of progressive social and political reforms such as social security and land reforms, including taxation of the rent on land. His government's most notable policy, however, was the nationalization of the Iranian oil industry, which had been under British control since 1913 through the Anglo-Persian Oil Company (APOC/AIOC) (later British Petroleum and BP)." The CIA cryptonym was Operation Ajax.

Like AC current and replicators, Luddites oppose every single innovation that advances society and decreases inequality because it removes their places at the apogee of the hierarchy, and interferes with their addiction to every-increasing profits. I don't use that term loosely. Charles Ferguson, Academy Award winning director of "Inside Job" alludes to it in the film.

An addiction is defined as "1 : the quality or state of being addicted addiction to reading; 2 : compulsive need for and use of a habit-forming substance (such as heroin, nicotine, or alcohol) characterized by tolerance and by well-defined physiological symptoms upon withdrawal; broadly : persistent compulsive use of a substance known by the user to be harmful" Merriam-Webster

Addiction: What other definition could be so apropos as a small minority of humanity makes insane amounts of money while harming the environment, exacerbating income inequality, encouraging wars along with arms dealing for-profit within the US (NRA), abroad and skating along the precipice of negative climate outcomes, nuclear annihilation to pump up a portfolio, or a trust fund they may contribute to; purchase of a new yacht on a planet no longer able to sustain life...including theirs?

Replicators and Mosaddegh have several common threads: economies of scarcity or post-scarcity, energy exploitation and distribution; the intervention by moneyed elites in the evolution of societies, scientific research either supported or suppressed into alternatives to fossil fuels and hierarchical, unequal societies bordering on dysfunction...and demise. The most common thread is choice of direction: either one or the other will sustain the species. Replicators are fiction; Mosaddegh, history.

"For the love of money is a root of all kinds of evil. Some people, eager for money, have wandered from the faith and pierced themselves with many griefs." 1 Tim 6:10

And many feigned any "faith" from the beginning to manipulate a bewildered herd to its avarice bidding. When most rain forests burn to the ground, the higher, greener canopies go crashing down with them. It's physics, not fantasy.
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Ebola 2.0...

Posted by Reginald L. Goodwin on May 10, 2018 at 8:10am
A health worker walks at an Ebola quarantine unit on June 13, 2017 in Muma, Congo. Credit: John Wessels Getty Images

Topics: Biology, Ebola, Existentialism, Politics

The fact that the erstwhile resident of 1600 Pennsylvania Avenue, conman, racist, thug and crook has labeled any countries with shades of Melanin darker than his orange hue as "s-hole countries," don't expect any help from the US anytime soon. As a matter-of-fact, I expect we'll look at Puerto Rico as halcyon days of functionality.

The new Ebola outbreak on the western edge of the Democratic Republic of the Congo has ignited serious concern at the World Health Organization, with signs pointing to an epidemic that may have been underway for weeks or months.

Though there are only two confirmed cases at this point, preliminary investigations point to cases in several locations that may date back as far as early this year, Dr. Pierre Formenty, the WHO’s top Ebola expert told STAT. There is also fear that two health care workers may be among the infected, which happens often in Ebola outbreaks and can fuel the disease’s spread.

The country’s ministry of health, which declared the outbreak on Tuesday, said then that there are at least 21 people known to have symptoms consistent with Ebola, and 17 of whom have died.

While the outbreak is in a remote area where road travel is taxing and slow, one of the towns where cases may be occurring, Bikoro, is a port on a lake that connects to the Congo River. That opens up the disturbing specter of infected individuals traveling by boat to DRC’s densely populated capital, Kinshasa, or to Brazzaville, the capital of the neighboring Republic of the Congo.

“If it was only the roads, we know that the roads are very bad and that it’s difficult for people to travel. But if you reach Bikoro and you take a boat … everything could happen,” Formenty said in an interview on Wednesday.

“For us it’s a worrying situation in a bad context in terms of logistics. And we need to go fast.”

WHO Officials Fear Latest Ebola Outbreak in Congo Could Spread to Big Cities Helen Branswell, Scientific American

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Marsquakes...

Posted by Reginald L. Goodwin on May 9, 2018 at 2:37pm
FILE PHOTO: The Mars InSight probe is shown in this artist's rendition operating on the surface of Mars, due to lift off from Vandenberg Air Force Base, California, U.S. on May 5, 2018 in this image obtained on May 3, 2018. NASA/ Handout via REUTERS/File Photo

Topics: Mars, NASA, Planetary Science, Space Exploration

LOS ANGELES (Reuters) - After decades exploring the surface of Mars, NASA is set for the weekend launch of its first robotic lander dedicated to studying the red planet’s deep interior, with instruments to detect planetary seismic rumblings never measured anywhere but Earth.

The Mars InSight probe is due for liftoff on Saturday before dawn from Vandenberg Air Force Base near the central California coast, treating early risers across a wide region to the luminous spectacle of the first interplanetary spacecraft to be launched from the U.S. West Coast.

The lander will be carried aloft for NASA and its Jet Propulsion Laboratory (JPL) atop a powerful, 19-story Atlas 5 rocket from the fleet of United Launch Alliance, a partnership of Lockheed Martin Corp and Boeing Co.

InSight will be released about 90 minutes after launch on a 301 million-mile (548 km) flight to Mars, and is due to reach its destination six months later, landing on a flat, smooth plain close to the planet’s equator called the Elysium Planitia.

The 800-pound (360 kg) spacecraft - its name is short for Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport - marks the 21st U.S.-launched Martian exploration, dating back to the Mariner fly-by missions of the 1960s. Nearly two dozen other Mars missions have been launched by other nations.

Spacecraft for detecting 'Marsquakes' set for rare California launch, Steve Gorman, Reuters Science

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Electroceuticals...

Posted by Reginald L. Goodwin on May 8, 2018 at 7:17am
Image Source: Eureka Alert! AAAS

Topics: Biology, Biochemistry, Bioengineering, Biomedicine

Light-induced processes at the interface between silicon-based structures and biological ones can be used to remotely control a wide range of biological activities – from single cell calcium signalling to brain activity – without any genetic engineering of the biological systems involved. The new finding could help in the development of “electroceuticals”, in which bioelectric signals could be modulated to treat disease. As well as biomedical applications, the toolkits employed could also be used to study fundamental biophysical processes.

Silicon-based materials are widely used in biological applications. Two examples include silicon nanowire-based transistors for electrically monitoring the signals in cardiomyocytes and bioelectronics implants for the heart. They are rarely found in remotely controlled and interconnect-free device set ups, however. This is because researchers do not fully understand the complex physicochemical processes at play at the interfaces between silicon and biological materials.

Remotely-controlled silicon structures could help treat disease, Belle Dumé, Nanotechweb.org

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Turing Filter...

Posted by Reginald L. Goodwin on May 7, 2018 at 10:43am
Alan Turing, pictured in a slate sculpture by Stephen Kettle, is known as a computer scientist and code breaker, but also made forays into mathematical biology. Credit: Steve Meddle/REX/Shutterstock

Topics: Biology, Computer Science, Diversity in Science, Mathematical Models, Nanotechnology

Researchers in China have developed a filter that removes salt from water up to three times as fast as conventional filters. The membrane has a unique nanostructure of tubular strands, inspired by the mathematical-biology work of codebreaker Alan Turing.

The filter is the most finely constructed example of the mathematician’s ‘Turing structures’ yet, and their first practical application, say researchers. “These 3D structures are quite extraordinary,” says Patrick Müller, a systems biologist at the Friedrich Miescher Laboratory in Tübingen, Germany. The filter’s tubular strands, just tens of nanometers in diameter, would be impossible to produce by other methods, such as 3D printing, he says. The work is published on 3 May in Science.

British mathematician Alan Turing is best known for his code-breaking exploits for the UK government during the Second World War, and as the father of computer science and artificial intelligence. But he also produced a seminal work in the then-nascent field of mathematical biology in 1952, just two years before his death.

In it, he proposed a mathematical model for a process by which the cells of an embryo might begin to form structures — limbs, bones and organs. In this process, two substances continuously react with each other but diffuse through their container at very different rates. The quicker-diffusing reactant — called the inhibitor — pushes back against the slower one, called the activator, effectively corralling the resulting product into a pattern of spots or stripes. (The terminology was coined by biologists Hans Meinhardt and Alfred Gierer, who independently formulated an equivalent theory in 1972.)

Water filter inspired by Alan Turing passes first test

Membrane's structure predicted in mathematician's lone biology paper.

Mark Zastrow, Nature

#P4TC: Turing Test...June 10, 2014

IMDB: The Imitation Game

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For Godot and Star Trek...

Posted by Reginald L. Goodwin on May 4, 2018 at 8:48am
Mind the gap: Around 13% of last authors in physics were women – a figure that is currently increasing at a rate of just 0.1% per year (courtesy: Jarmoluk on Pixabay)

Topics: Diversity in Science, Existentialism, Star Trek, STEM, Women in Science

Cultural reference in blog title: Waiting for Godot, by Samuel Beckett (Wikipedia)

Much has been seen recently in the #BlackLivesMatter, #MeToo, #TimesUp and subsequently, #MarchForOurLives movements. Things that are and have been systemic in our society are being questioned by those groups affected. Indignities and injustices aren't being tolerated anymore. Even the March for Science is a reaction to the adversarial relationship between science and power, as in many cases the answers research may yield not fitting well with the agreed dogma of political forces.

Many women and minorities were inspired into STEM careers due to the Roddenberry franchise, itself born of the often violent and lethal unrest in the sixties, and a hope we would resolve our differences both national and personal through rational actions and discourse, personified in the character of Spock played by the late Leonard Nimoy. Despite his alien origins, he was an outsider of two worlds: Earth and Vulcan; part of each and not fully accepted by either. What we saw was a possibility of acceptance based on merit, not blocked by gender, culture or preconceived biases.

Alas, science is not populated by dispassionate Data's devoid of emotion chips. Every single one of us comes into the field with our life experiences and conditioned prejudices of a person's worth in our particular fields. I have no doubt that part of the issue is how we're socializing our children into preassigned roles. For example, I remember my "toys" being G.I. Joe with the "Kung Fu" grip; a chemistry set, an erector sets, a microscope, a telescope and a junior construction tool kit. My female neighbor friends mostly had Barbies and teddy bears. I don't think much has changed.

We may be forcing the solution to society's most daunting problems in pigtails with dolls, rather than electronic snap kits and microscopes. The current estimate of gender parity puts us in the fictional Kirk era. That's assuming we survive as a species, daunted by current population growth, our projected population growth and a lack of starships.

Physics has one of the largest gender gaps in science, technology, engineering, mathematics and medicine (STEMM) according to an analysis of more than 36 million authors of academic papers over the last two decades (PLoS Biol 16(4) e2004956). The study, carried out by researchers at the University of Melbourne in Australia, says that at current rates it will be more than two centuries until there are equal numbers of senior male and female researchers in physics.

While the proportion of women in most STEMM fields is increasing, Luke Holman and his colleagues used computational methods to estimate the speed of change. They did this by estimating the gender of 36.6 million authors on 9.7 million papers the databases PubMed and arXiv. In the latter, for example, the researchers say they were able to estimate – with 95% confidence – the gender of 1.18 million authors from 538,688 preprint published since 1991.

If we want to see 50% of physicists being women sooner we need to implement new initiatives to do this – over and above any currently-running initiatives

Luke Holman, University of Melbourne

Gender gap in physics among highest in science, Michael Allen, Physics World

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Eddy's, Nacelles and Wind Efficiency...

Posted by Reginald L. Goodwin on May 3, 2018 at 1:02pm
Color contours account for the creation of mean kinetic energy along the spanwise direction. Positive values (red) indicate a turbulent kinetic energy flux in the negative spanwise direction, while negative (blue) values denote a flux in the positive spanwise direction. For both set of simulations, by increasing the tip speed ratio, the entrainment of mean kinetic energy increases for a given streamwise distance from the rotor disk.

Topics: Alternative Energy, Computer Science, Economics, Economy, Green Tech, Jobs, Mathematical Models

A team of researchers from The University of Texas at Dallas (UT Dallas) has developed a new way to extract more power from the wind. This approach has the potential to increase wind power generation significantly with a consequent increase in revenue. Numerical simulations performed at the Texas Advanced Computing Center (TACC) indicate potential increases of up to six to seven percent.

According to the researchers, a one percent improvement applied to all wind farms in the nation would generate the equivalent of $100 million in value. This new method, therefore, has the potential to generate $600 million in added wind power nationwide.

The team reported their findings in Wind Energy in December 2017 and Renewable Energy in December 2017.

In the branch of physics known as fluid dynamics, a common way to model turbulence is through large eddy simulations. Several years ago, Stefano Leonardi and his research team created models that can integrate physical behavior across a wide range of length scales — from turbine rotors 100 meters long, to centimeters-thick tips of a blades — and predict wind power with accuracy using supercomputers.

New Energy Control Strategy Helps Reap Maximum Power from Wind Farms

Aaron Dubrow, Texas Advanced Computing Center, University of Texas, Dallas

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Phonon Heat Transfer...

Posted by Reginald L. Goodwin on May 2, 2018 at 8:29am
Illustration of the quartz plates used to measure heat transfer. The coloured regions are electrodes used to position the plates. Courtesy: M Ghashami et al/Phys. Rev. Lett.)

Topics: Electrical Engineering, Experimental Physics, Thermodynamics

New insights into why heat transfer between objects is enhanced at very short separations have been gleaned by Keunhan Park and colleagues at the University of Utah and University of Pittsburgh in the US. The team made exquisitely precise measurements of how heat moves between two quartz plates that are positioned just 200 nm apart. They found that energy transfer is enhanced by about 45 times at tiny separations, which they ascribe to the coupling of surface photon polaritons across the gap between the plates.

Normally, the heat transfer between two objects at different temperatures can be approximated by assuming that the objects are “black bodies”. These are ideal entities that absorb all radiation falling on them and emit thermal radiation according to Planck’s law. Physicists have known for some time that this breaks down when objects get to within a few hundred nanometres of each other, where they exchange heat much faster than predicted by the black-body approximation. Indeed, this “near-field” enhancement has already been used in some technologies including heat extraction and thermophotovoltaic systems.

However, more widespread use of the enhancement has been hampered by a poor understanding of the effect – which is a result of significant experimental difficulties in measuring heat transfer between objects separated by just a few hundred nanometres. These challenges include controlling unwanted heat flow and achieving precise control over the orientation and separation of the two objects.

Surface phonon polaritons boost heat transfer, Hamish Johnston, Physics World

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Funnel Booster...

Posted by Reginald L. Goodwin on May 1, 2018 at 8:00am
a) Schematic shows the band structure of the semiconducting HfS2/HfO2 when under strain, and the consequent charge funnelling. b) The strain is induced in the semiconductor by creating a region of oxide using intense laser light. c) A photocurrent map of the device; the photoresponse drastically increases when a region (dashed circle, bottom) is oxidized, compared with the same device before oxidation (top), a sign of the charge funnelling effect. Figure reproduced with permission from the authors and Nature Communications.

Topics: Green Energy, Green Tech, Laser, Nanotechnology, Semiconductor Technology, Solar Power

Note: Radiant solar energy = 1.1 x 10^18 kilowatt hours/year; 3.013 x 10^15 kilowatt hours/day. We're literally "leaving money on the table"... for fossil fuel greed.

Source: United Nations World Energy Assessment: Energy and the Challenge of Sustainability

Funnels are efficient tools for channelling liquids into containers with narrow openings. Now, researchers in Exeter have demonstrated the first funnel for electrical charges on a chip. The discovery builds on the ability to oxidize the atomically thin semiconductor, hafnium disulphide (HfS2), with a high-intensity UV laser. The non-uniform strain between oxidized and non-oxidized regions, and the subsequent band-gap modulation, generates electric fields, which effectively funnel the charges in the semiconductor flakes to areas where they can be more easily collected. This concept could enable a new generation of solar cells with 60% efficiency (currently around 21%), thanks to the increased efficiency in collecting photo-excited charges and the potential for hot-carrier extraction.

Intense laser light means oxidation, oxidation means strain

In general, bulk semiconductors can only sustain strains up to 0.4% before breaking. However, a layer of semiconductor that is only a few atoms thick can support strains of up to 25%. This amount of strain changes the band gap in the energy dispersion by up to 1 eV. In this work, Saverio Russo and his group at the University of Exeter, induce the strain in the HfS2 using a 375 nm laser to remove sulphur atoms, which are then replaced by oxygen atoms. According to calculations performed using density functional theory, the hafnium atoms have different separations in HfS2 and HfO2. This produces a 2.7% strain at the boundary between the oxidized and non-oxidized regions. Electrical contacts anchor the material to a substrate, so a strain gradient is present across the whole flake, shifting asymmetrically the conduction and valence bands to higher energies, and opening the band gap by 30 meV.

Funneling charges to boost solar-cell efficiency, Lauren Barr, PhD, network contributor for nanotechweb.org

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