Friday, October 30, 2015
Thursday, October 29, 2015
Tuesday, October 27, 2015
Monday, October 26, 2015
Stock Market Remains Headed for a 2007 or 1929 Crash
The right kind of technical analysis can yield useful predictions, however. The decision support engine, a technical analysis system that tracks a wide range of data and looks for historical patterns that are likely to repeat themselves, has yielded accurate predictions about the broad market since early August. Here are just a few of the articles describing its forecasts that were published before the market's behavior confirmed them.
1. Aug. 7, 2015: "The Stock Market is Getting Ready to Plummet, but Volatility Will Soar"
Must Read: 4 Stocks With Most Elite Dividend-Grower Status
3. Sept. 29, 2015: "Stocks Will Make a Multiweek Bounce Before the Coming Market Collapse"
Last Wednesday, there was an article titled, "5 Reasons the Stock Market Will Move Sharply Lower Soon," which highlighted the decision support engine's latest forecast. This prediction still awaits the market's manifestation. In August, we asked whether this year's big selloff would be like 2007-2008 or 1929. Updated information shows that there still are reasons to expect either of those scenarios, but right now the 2007 analogue has a slight edge.
If this is the market's path, the S&P 500's (^GSPC) rise off the Aug. 24 low has mimicked the rise off the March 2008 low into the lower high in May 2008. That May high marked the last escape before the next 10 months saw the S&P 500 lose 53%. If that happens in the next 12 to 24 months, the S&P 500 will test the 1050 zone.
Click here to see the following chart in a new window
This weekly bar chart of the S&P 500 above shows the peak in 2007, the decline into March, then the rise to lower highs in May. That May 2008 high intersected the just-broken lower channel line (thick green line) from the underside, as well as the 200-day moving average (thin blue line) from the underside, in a classic "kiss goodbye" of long-standing previous support (which is now resistance).
The second chart is a monthly bar chart, and it shows how the current scenario echoes that of 2007-2008. The red box from the first chart is translated to the 2008 time frame, and the current scenario shows one, as well. Notice that the lower just-broken channel lines, 200-day moving averages, and even the initial touch of the lower two-standard-deviation band (olive/gold line) are all eerily similar. Then, drop down into the stochastics pane and you will see the bold blue lines there highlighting the lower highs in stochastics vs. higher highs in prices in the months leading into the 2007 and 2015 peaks. Finally, the current stochastics are in free fall, represented by the red stochastic widening the distance from the green stochastic.
Must Read: The Week Ahead: Will Stocks Stay in the Black?
If the 1929 analogue is in play, prices will streak to higher highs by New Year's Eve, if not Thanksgiving or even Halloween! All that is needed to satisfy the pattern is an S&P 500 print above 2135 (less than 3% higher Friday's close), while higher targets can be calculated to 2400 +/-25. However, the conditions of waning volume, momentum, and breadth, coupled with extreme complacency (i.e., the CBOE Volatility Index, or VIX), bullishness (record New York Stock Exchange margin usage) and certainty that the Federal Reserve "has our backs" put this bubble into rarefied territory. Bulls are likely to get slaughtered in the near future.
The decision support engine is warning strongly that this is not the time to be using buying actions in your portfolio (except for marrying some put options to your beloved long positions). Rather, selling actions are indicated, which means selling long positions, using sell stops to protect profits and selling short. Sell, sell, sell!
For more of this kind of analysis, join our new real-time, live-market analysis chat room. Come benefit from decision support engine analysis from bell to bell, addressing indices and stocks, as well as member questions throughout the day. Special founding member pricing is available for TheStreet.com readers who subscribe early, after enjoying a complimentary trial week.
This article is commentary by an independent contributor. At the time of publication, the author held shares of ProShares Trust UltraPro Short QQQ ETF (SQQQ).
Cobalt atoms on graphene a powerful combo
http://nextbigfuture.com/
October 25, 2015
Graphene
doped with nitrogen and augmented with cobalt atoms has proven to be an
effective, durable catalyst for the production of hydrogen from water,
according to scientists at Rice University.
The Rice lab of chemist James Tour and colleagues at the Chinese Academy of Sciences, the University of Texas at San Antonio and the University of Houston have reported the development of a robust, solid-state catalyst that shows promise to replace expensive platinum for hydrogen generation.
A
new catalyst just 15 microns thick has proven nearly as effective as
platinum-based
The Rice lab of chemist James Tour and colleagues at the Chinese Academy of Sciences, the University of Texas at San Antonio and the University of Houston have reported the development of a robust, solid-state catalyst that shows promise to replace expensive platinum for hydrogen generation.
catalysts but at a much lower cost, according to
scientists at Rice University. The
catalyst is made of nitrogen-doped
graphene with individual cobalt atoms that activate
the process.
(Credit: Tour Group/Rice University)
Nature Communications - Atomic cobalt on nitrogen-doped graphene for hydrogen generation
Catalysts can split water into its constituent hydrogen and oxygen atoms, a process required for fuel cells. The latest discovery, detailed in Nature Communications, is a significant step toward lower-cost catalysts for energy production, according to the researchers.
“What’s unique about this paper is that we show not the use of metal particles, not the use of metal nanoparticles, but the use of atoms,” Tour said. “The particles doing this chemistry are as small as you can possibly get.”
Even particles on the nanoscale work only at the surface, he said. “There are so many atoms inside the nanoparticle that never do anything. But in our process the atoms driving catalysis have no metal atoms next to them. We’re getting away with very little cobalt to make a catalyst that nearly matches the best platinum catalysts.” In comparison tests, he said the new material nearly matched platinum’s efficiency to begin reacting at a low onset voltage, the amount of electricity it needs to begin separating water into hydrogen and oxygen.
The new catalyst is mixed as a solution and can be reduced to a paper-like material or used as a surface coating. Tour said single-atom catalysts have been realized in liquids, but rarely on a surface. “This way we can build electrodes out of it,” he said. “It should be easy to integrate into devices.”
The researchers discovered that heat-treating graphene oxide and small amounts of cobalt salts in a gaseous environment forced individual cobalt atoms to bind to the material.
Electron microscope images showed cobalt atoms widely dispersed throughout the samples.
They tested nitrogen-doped graphene on its own and found it lacked the ability to kick the catalytic process into gear. But adding cobalt in very small amounts significantly increased its ability to split acidic or basic water.
“This is an extremely high-performance material,” Tour said. He noted platinum-carbon catalysts still boast the lowest onset voltage. “No question, they’re the best. But this is very close to it and much easier to produce and hundreds of times less expensive.”
Atom-thick graphene is the ideal substrate, Tour said, because of its high surface area, stability in harsh operating conditions and high conductivity. Samples of the new catalyst showed a negligible decrease in activity after 10 hours of accelerated degradation studies in the lab.
Abstract
Reduction of water to hydrogen through electrocatalysis holds great promise for clean energy, but its large-scale application relies on the development of inexpensive and efficient catalysts to replace precious platinum catalysts. Here we report an electrocatalyst for hydrogen generation based on very small amounts of cobalt dispersed as individual atoms on nitrogen-doped graphene. This catalyst is robust and highly active in aqueous media with very low overpotentials (30 mV). A variety of analytical techniques and electrochemical measurements suggest that the catalytically active sites are associated with the metal centres coordinated to nitrogen. This unusual atomic constitution of supported metals is suggestive of a new approach to preparing extremely efficient single-atom catalysts.
Nature Communications - Atomic cobalt on nitrogen-doped graphene for hydrogen generation
Catalysts can split water into its constituent hydrogen and oxygen atoms, a process required for fuel cells. The latest discovery, detailed in Nature Communications, is a significant step toward lower-cost catalysts for energy production, according to the researchers.
“What’s unique about this paper is that we show not the use of metal particles, not the use of metal nanoparticles, but the use of atoms,” Tour said. “The particles doing this chemistry are as small as you can possibly get.”
Even particles on the nanoscale work only at the surface, he said. “There are so many atoms inside the nanoparticle that never do anything. But in our process the atoms driving catalysis have no metal atoms next to them. We’re getting away with very little cobalt to make a catalyst that nearly matches the best platinum catalysts.” In comparison tests, he said the new material nearly matched platinum’s efficiency to begin reacting at a low onset voltage, the amount of electricity it needs to begin separating water into hydrogen and oxygen.
The new catalyst is mixed as a solution and can be reduced to a paper-like material or used as a surface coating. Tour said single-atom catalysts have been realized in liquids, but rarely on a surface. “This way we can build electrodes out of it,” he said. “It should be easy to integrate into devices.”
The researchers discovered that heat-treating graphene oxide and small amounts of cobalt salts in a gaseous environment forced individual cobalt atoms to bind to the material.
Electron microscope images showed cobalt atoms widely dispersed throughout the samples.
They tested nitrogen-doped graphene on its own and found it lacked the ability to kick the catalytic process into gear. But adding cobalt in very small amounts significantly increased its ability to split acidic or basic water.
“This is an extremely high-performance material,” Tour said. He noted platinum-carbon catalysts still boast the lowest onset voltage. “No question, they’re the best. But this is very close to it and much easier to produce and hundreds of times less expensive.”
Atom-thick graphene is the ideal substrate, Tour said, because of its high surface area, stability in harsh operating conditions and high conductivity. Samples of the new catalyst showed a negligible decrease in activity after 10 hours of accelerated degradation studies in the lab.
Abstract
Reduction of water to hydrogen through electrocatalysis holds great promise for clean energy, but its large-scale application relies on the development of inexpensive and efficient catalysts to replace precious platinum catalysts. Here we report an electrocatalyst for hydrogen generation based on very small amounts of cobalt dispersed as individual atoms on nitrogen-doped graphene. This catalyst is robust and highly active in aqueous media with very low overpotentials (30 mV). A variety of analytical techniques and electrochemical measurements suggest that the catalytically active sites are associated with the metal centres coordinated to nitrogen. This unusual atomic constitution of supported metals is suggestive of a new approach to preparing extremely efficient single-atom catalysts.
http://www.gizmag.com/
High-efficiency, semi-transparent perovskite/graphene solar cells created at low cost
- Colin Jeffrey
- September 11, 2015
The semi-transparent, inexpensive solar cells have a claimed
conversion efficiency of around 12 percent
(Credit: Hong Kong Polytechnic University)
conversion efficiency of around 12 percent
(Credit: Hong Kong Polytechnic University)
With the continued rise in the uptake of solar cells, consumers are now
looking at less obtrusive ways to incorporate these in buildings and vehicles. Transparent or semi-transparent cells
provide greater flexibility and visual appeal than standard, opaque
silicon solar cells, however their relatively high-cost and poor
efficiencies have meant that their adoption has been slow. To help remedy
this, researchers working at the Hong Kong Polytechnic University
(PolyU) have created semi-transparent, efficient, low-cost perovskite
solar cells with graphene electrodes.
First generation silicon solar cells have been the mainstay of photovoltaic (PV) energy conversion for many years now due to their high stability and efficient energy conversion, but their opacity and expense mean that alternatives are now being actively sought for modern building and vehicle applications. Thin film PVs (second generation solar cells) are lightweight and flexible, but are expensive because they are created from rare materials using complex structures requiring high-temperature production processes.
Now, utilizing such materials as thin-film perovskite, the third generation of solar cell is currently being developed for commercial use in the not-too-distant future with the promise of greater power conversion efficiencies, simpler fabrication processes, and lower cost.
In this vein, the PolyU researchers have developed their own version of the third generation solar cell using semitransparent perovskite with graphene used as the electrodes. Being exceptionally thin but with high conductivity and low cost, graphene makes an ideal choice for semitransparent solar cells as it allows light to be absorbed from both sides. As such, the researchers envisage these devices potentially able to be used in windows, louvers, and building roof surfaces, thereby increasing the available surface area for collecting solar energy.
With a claimed power conversion efficiency of around 12 percent, the PolyU solar cells outperform standard transparent and semi-transparent versions hands-down. The potential to be produced at less than HK $0.50 (US $0.06)/Watt also means a greater than 50 percent saving on the cost of conventional silicon solar cells.
While graphene has been around for more than a decade now and is highly-efficient as a conductor in its own right, the PolyU researchers decided to further enhance the conductivity of graphene to meet their specific requirements. To do this, the graphene was coated with a patina of PEDOT:PSS conductive polymer (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) – the same ingredient recently used by KAIST scientists in the production of weavable LED fibers – that also acted as an adhesion layer to the perovskite during the process of lamination.
To promote power conversion efficiency, the researchers found that by multilayering graphene through chemical vapor deposition to create transparent electrodes, the sheet resistance of the electrodes was additionally reduced while the exceptional transparency of the electrodes was retained. Finally, the performance of the device was further improved by enhancing the degree of contact between the top graphene electrodes and the hole transport layer on the perovskite film.
According to the researchers, the exceptional flexibility of graphene and the simplified preparation of the cells means that the PolyU device could be eminently suitable for mass production via direct printing or using a roll-to-roll process. In this way, semitransparent solar cells may well provide a greater uptake of PV panels across markets not currently serviced by traditional, opaque devices.
The results of this research were published in the journal Advanced Materials.
Source: Hong Kong Polytechnic University
An
alloy first made nearly two decades ago by the U. S. Navy could provide
an efficient new way to produce electricity. The material, dubbed
Galfenol, consists of iron doped with the metal gallium. In new
experiments, researchers from UCLA, the University of North Texas (UNT),
and the Air Force Research Laboratories have shown that Galfenol can
generate as much as 80 megawatts of instantaneous power per square meter
under strong impacts.
Galfenol converts energy with high efficiency; it is able to turn roughly 70 percent of an applied mechanical energy into magnetic energy, and vice versa. (A standard car, by contrast, converts only about 15 to 30 percent of the stored energy in gasoline into useful motion.) Significantly, the magnetoelastic effect can be used to generate electricity. "If we wrap some wires around the material, we can generate an electrical current in the wire due to a change in magnetization," Domann said.
Galfenol in experiments using a device called a Split-Hopkinson Pressure Bar to generate high amounts of compressive stress (e.g., powerful impacts). They found that when subjected to impacts, Galfenol generates as much as 80 megawatts of instantaneous power per cubic meter.
By way of comparison, a device known as an explosively driven ferromagnetic pulse generator produces 500 megawatts of power per cubic meter. However, as their name implies, such generators require an explosion—one that destroys the ferromagnet, even as it produces power.
Among the potential applications, Galfenol-powered devices could be used as wireless impact detectors. "Essentially, we could fabricate small devices that send out a detectable electromagnetic wave when a mechanical pulse moves through it," Domann said. These devices could be embedded in vehicles—military or civilian—to detect collisions. Because electromagnetic waves travel three orders of magnitude faster than mechanical waves, information about the impact could be transmitted ahead of the waves created by the impact.
This picture is of the experimental setup showing the Hopkinson bar
First generation silicon solar cells have been the mainstay of photovoltaic (PV) energy conversion for many years now due to their high stability and efficient energy conversion, but their opacity and expense mean that alternatives are now being actively sought for modern building and vehicle applications. Thin film PVs (second generation solar cells) are lightweight and flexible, but are expensive because they are created from rare materials using complex structures requiring high-temperature production processes.
Now, utilizing such materials as thin-film perovskite, the third generation of solar cell is currently being developed for commercial use in the not-too-distant future with the promise of greater power conversion efficiencies, simpler fabrication processes, and lower cost.
In this vein, the PolyU researchers have developed their own version of the third generation solar cell using semitransparent perovskite with graphene used as the electrodes. Being exceptionally thin but with high conductivity and low cost, graphene makes an ideal choice for semitransparent solar cells as it allows light to be absorbed from both sides. As such, the researchers envisage these devices potentially able to be used in windows, louvers, and building roof surfaces, thereby increasing the available surface area for collecting solar energy.
With a claimed power conversion efficiency of around 12 percent, the PolyU solar cells outperform standard transparent and semi-transparent versions hands-down. The potential to be produced at less than HK $0.50 (US $0.06)/Watt also means a greater than 50 percent saving on the cost of conventional silicon solar cells.
While graphene has been around for more than a decade now and is highly-efficient as a conductor in its own right, the PolyU researchers decided to further enhance the conductivity of graphene to meet their specific requirements. To do this, the graphene was coated with a patina of PEDOT:PSS conductive polymer (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) – the same ingredient recently used by KAIST scientists in the production of weavable LED fibers – that also acted as an adhesion layer to the perovskite during the process of lamination.
To promote power conversion efficiency, the researchers found that by multilayering graphene through chemical vapor deposition to create transparent electrodes, the sheet resistance of the electrodes was additionally reduced while the exceptional transparency of the electrodes was retained. Finally, the performance of the device was further improved by enhancing the degree of contact between the top graphene electrodes and the hole transport layer on the perovskite film.
According to the researchers, the exceptional flexibility of graphene and the simplified preparation of the cells means that the PolyU device could be eminently suitable for mass production via direct printing or using a roll-to-roll process. In this way, semitransparent solar cells may well provide a greater uptake of PV panels across markets not currently serviced by traditional, opaque devices.
The results of this research were published in the journal Advanced Materials.
Source: Hong Kong Polytechnic University
http://nextbigfuture.com/
September 29, 2015
Galfenol can convert 70 percent of an applied mechanical energy into magnetic energy
Galfenol converts energy with high efficiency; it is able to turn roughly 70 percent of an applied mechanical energy into magnetic energy, and vice versa. (A standard car, by contrast, converts only about 15 to 30 percent of the stored energy in gasoline into useful motion.) Significantly, the magnetoelastic effect can be used to generate electricity. "If we wrap some wires around the material, we can generate an electrical current in the wire due to a change in magnetization," Domann said.
Galfenol in experiments using a device called a Split-Hopkinson Pressure Bar to generate high amounts of compressive stress (e.g., powerful impacts). They found that when subjected to impacts, Galfenol generates as much as 80 megawatts of instantaneous power per cubic meter.
By way of comparison, a device known as an explosively driven ferromagnetic pulse generator produces 500 megawatts of power per cubic meter. However, as their name implies, such generators require an explosion—one that destroys the ferromagnet, even as it produces power.
Among the potential applications, Galfenol-powered devices could be used as wireless impact detectors. "Essentially, we could fabricate small devices that send out a detectable electromagnetic wave when a mechanical pulse moves through it," Domann said. These devices could be embedded in vehicles—military or civilian—to detect collisions. Because electromagnetic waves travel three orders of magnitude faster than mechanical waves, information about the impact could be transmitted ahead of the waves created by the impact.
This picture is of the experimental setup showing the Hopkinson bar
surrounded by a water-cooled electromagnet. A cylinder of Galfenol
is
inside of the electromagnet, sandwiched between the Hopkinson bars.
The
magnet was used to apply a wide range of static magnetic fields to
Galfenol while it was mechanically impacted. Credit: John Domann/UCLA
Journal of Applied Physics - High strain-rate magnetoelasticity in Galfen
This paper presents the experimental measurements of a highly magnetoelastic material (Galfenol) under impact loading. A Split-Hopkinson Pressure Bar was used to generate compressive stress up to 275 MPa at strain rates of either 20/s or 33/s while measuring the stress-strain response and change in magnetic flux density due to magnetoelastic coupling. The average Young's modulus (44.85 GPa) was invariant to strain rate, with instantaneous stiffness ranging from 25 to 55 GPa. A lumped parameters model simulated the measured pickup coil voltages in response to an applied stress pulse. Fitting the model to the experimental data provided the average piezomagnetic coefficient and relative permeability as functions of field strength. The model suggests magnetoelastic coupling is primarily insensitive to strain rates as high as 33/s. Additionally, the lumped parameters model was used to investigate magnetoelastic transducers as potential pulsed power sources. Results show that Galfenol can generate large quantities of instantaneous power (80 MW/m3 ), comparable to explosively driven ferromagnetic pulse generators (500 MW/m3 ). However, this process is much more efficient and can be cyclically carried out in the linear elastic range of the material, in stark contrast with explosively driven pulsed power generators.
A Kolsky bar was used to generate large constant strain rates in Galfenol, and measure the stress-strain response, as well as the change in magnetic flux density due to magnetoelastic coupling. The experimental results indicate that the average Young's modulus of Galfenol is invariant with increasing strain rates of up to 33/s. The measured voltage was proportional to strain rate, with a more rounded appearance, attributed to dynamic magnetic effects. Furthermore, the measured voltage and change in flux were highly dependent on bias field strength. A lumped parameters model was created that effectively simulates the measured pickup coil voltages in response to an applied stress pulse. The model suggests that magnetoelastic coupling is relatively insensitive to strain rates as high as 33/s. The model also suggests that Galfenol can generate large quantities of instantaneous power, comparable to those created by explosively driven ferromagnetic pulse generators. However, this process is much more efficient and can be cyclically carried out in the linear elastic range of the material, in stark contrast with explosively driven pulsed power generators.
SOURCES- UCLA, Phys.org, Journal of Applied Physics
Journal of Applied Physics - High strain-rate magnetoelasticity in Galfen
This paper presents the experimental measurements of a highly magnetoelastic material (Galfenol) under impact loading. A Split-Hopkinson Pressure Bar was used to generate compressive stress up to 275 MPa at strain rates of either 20/s or 33/s while measuring the stress-strain response and change in magnetic flux density due to magnetoelastic coupling. The average Young's modulus (44.85 GPa) was invariant to strain rate, with instantaneous stiffness ranging from 25 to 55 GPa. A lumped parameters model simulated the measured pickup coil voltages in response to an applied stress pulse. Fitting the model to the experimental data provided the average piezomagnetic coefficient and relative permeability as functions of field strength. The model suggests magnetoelastic coupling is primarily insensitive to strain rates as high as 33/s. Additionally, the lumped parameters model was used to investigate magnetoelastic transducers as potential pulsed power sources. Results show that Galfenol can generate large quantities of instantaneous power (80 MW/m3 ), comparable to explosively driven ferromagnetic pulse generators (500 MW/m3 ). However, this process is much more efficient and can be cyclically carried out in the linear elastic range of the material, in stark contrast with explosively driven pulsed power generators.
A Kolsky bar was used to generate large constant strain rates in Galfenol, and measure the stress-strain response, as well as the change in magnetic flux density due to magnetoelastic coupling. The experimental results indicate that the average Young's modulus of Galfenol is invariant with increasing strain rates of up to 33/s. The measured voltage was proportional to strain rate, with a more rounded appearance, attributed to dynamic magnetic effects. Furthermore, the measured voltage and change in flux were highly dependent on bias field strength. A lumped parameters model was created that effectively simulates the measured pickup coil voltages in response to an applied stress pulse. The model suggests that magnetoelastic coupling is relatively insensitive to strain rates as high as 33/s. The model also suggests that Galfenol can generate large quantities of instantaneous power, comparable to those created by explosively driven ferromagnetic pulse generators. However, this process is much more efficient and can be cyclically carried out in the linear elastic range of the material, in stark contrast with explosively driven pulsed power generators.
SOURCES- UCLA, Phys.org, Journal of Applied Physics
http://nextbigfuture.com/
September 29, 2015
Solar Cells Will be Made Obsolete by 3D rectennas aiming at 40-to-90% efficiency
A new kind of nanoscale rectenna (half antenna and half rectifier) can convert solar and infrared into electricity, plus be tuned to nearly any other frequency as a detector.
Right now efficiency is only one percent, but professor Baratunde Cola and colleagues at the Georgia Institute of Technology (Georgia Tech, Atlanta) convincingly argue that they can achieve 40 percent broad spectrum efficiency (double that of silicon and more even than multi-junction gallium arsenide) at a one-tenth of the cost of conventional solar cells (and with an upper limit of 90 percent efficiency for single wavelength conversion).
It is well suited for mass production, according to Cola. It works by growing fields of carbon nanotubes vertically, the length of which roughly matches the wavelength of the energy source (one micron for solar), capping the carbon nanotubes with an insulating dielectric (aluminum oxide on the tethered end of the nanotube bundles), then growing a low-work function metal (calcium/aluminum) on the dielectric and voila--a rectenna with a two electron-volt potential that collects sunlight and converts it to direct current (DC).
"Our process uses three simple steps: grow a large array of nanotube bundles vertically; coat one end with dielectric; then deposit another layer of metal," Cola told EE Times. "In effect we are using one end of the nanotube as a part of a super-fast metal-insulator-metal tunnel diode, making mass production potentially very inexpensive up to 10-times cheaper than crystalline silicon cells."
For commercialization, billions or even trillions of carbon-nanotube bundles could be grown side-by-side, ramping up the power output into the megaWatt range, after optimization for higher efficiency.
"We still have a lot of work to do to lower contact resistance which will improve the impedance match between the antenna and diode, thus raising efficiency," Cola told us."Our proof-of-concept was tuned to the near-infrared. We used infrared-, solar- and green laser-light and got efficiencies of less than one percent, but what was key to our demo was we showed our computer model matched our experimental results, giving us the confidence that we can improve the efficiency up to 40 percent in just a few years."
For the future, Cola's group has a three tiered goal--first develop sensor applications that don't require high efficiencies, second to get the efficiency to 20 percent for harvesting waste heat in the infrared spectrum, then start replacing standard solar cells with 40 percent efficient panels in the visible spectrum. The team is also seeking suitable flexible substrates for applications that require bending.
capped with a metal-oxide-metal tunneling diode. (Credit: Thomas
Bougher)
(Source: Georgia Tech)
Nature Nanotechnology - A carbon nanotube optical rectenna
An optical rectenna—a device that directly converts free-propagating electromagnetic waves at optical frequencies to direct current—was first proposed over 40 years ago, yet this concept has not been demonstrated experimentally due to fabrication challenges at the nanoscale. Realizing an optical rectenna requires that an antenna be coupled to a diode that operates on the order of 1 pHz (switching speed on the order of 1 fs). Diodes operating at these frequencies are feasible if their capacitance is on the order of a few attofarads but they remain extremely difficult to fabricate and to reliably couple to a nanoscale antenna. Here we demonstrate an optical rectenna by engineering metal–insulator–metal tunnel diodes, with a junction capacitance of ∼2 aF, at the tip of vertically aligned multiwalled carbon nanotubes (∼10 nm in diameter), which act as the antenna. Upon irradiation with visible and infrared light, we measure a d.c. open-circuit voltage and a short-circuit current that appear to be due to a rectification process (we account for a very small but quantifiable contribution from thermal effects). In contrast to recent reports of photodetection based on hot electron decay in a plasmonic nanoscale antenna a coherent optical antenna field appears to be rectified directly in our devices, consistent with rectenna theory. Finally, power rectification is observed under simulated solar illumination, and there is no detectable change in diode performance after numerous current–voltage scans between 5 and 77 °C, indicating a potential for robust operation.
(Source: Georgia Tech)
Nature Nanotechnology - A carbon nanotube optical rectenna
An optical rectenna—a device that directly converts free-propagating electromagnetic waves at optical frequencies to direct current—was first proposed over 40 years ago, yet this concept has not been demonstrated experimentally due to fabrication challenges at the nanoscale. Realizing an optical rectenna requires that an antenna be coupled to a diode that operates on the order of 1 pHz (switching speed on the order of 1 fs). Diodes operating at these frequencies are feasible if their capacitance is on the order of a few attofarads but they remain extremely difficult to fabricate and to reliably couple to a nanoscale antenna. Here we demonstrate an optical rectenna by engineering metal–insulator–metal tunnel diodes, with a junction capacitance of ∼2 aF, at the tip of vertically aligned multiwalled carbon nanotubes (∼10 nm in diameter), which act as the antenna. Upon irradiation with visible and infrared light, we measure a d.c. open-circuit voltage and a short-circuit current that appear to be due to a rectification process (we account for a very small but quantifiable contribution from thermal effects). In contrast to recent reports of photodetection based on hot electron decay in a plasmonic nanoscale antenna a coherent optical antenna field appears to be rectified directly in our devices, consistent with rectenna theory. Finally, power rectification is observed under simulated solar illumination, and there is no detectable change in diode performance after numerous current–voltage scans between 5 and 77 °C, indicating a potential for robust operation.
Friday, October 23, 2015
The Flying Pin-Up Girls: Cheeky WWII Airplane Nose Art!
Nose art was the technique of decorating combat aircraft during the World War II. We know, we have already shown you some nose art, but we just cannot resist them.
Female pin-up art dominated World War II nose art, seeing its Golden Age through the Korean War, tolerated by Army Air Force officials to help boost the morale of the soldiers fighting in stressful wars with high probabilities of death.
Take a look at the below collection of cheeky pin-ups airplane nose art.
Wednesday, October 21, 2015
Sunday, October 18, 2015
Saturday, October 17, 2015
5 Mini PCs That Will Turn Your Dumb TV Into a “Smart” TV
http://www.cheatsheet.com/gear-style/?ref=TN
Smart TVs are extremely convenient. Generally, they include
integrated Wi-Fi which allows you to tap into the Internet to stream
content from one of many providers like Netflix or Hulu. Of course,
Smart TVs are a relatively new development. Not all TVs can connect
directly to the Internet and stream content, at least not without
another device hooked up.
You can always purchase a set-top device like Roku, Google Chromecast, Apple TV, or even the Amazon Fire TV. However, these devices have limitations on what type of content or media they can stream. It would be much more beneficial to connect a computer or PC to your TV. Then you can stream all kinds of media, but you can also browse the Internet, play games, and run applications.
Nobody wants a large tower sitting beside their TV, though, and laptops tend to look silly, and, really, they’re only temporarily useful in this regard. Who wants a messy console or entertainment system with wires protruding everywhere?
That’s where Mini PCs or HTPCs come into play.
The HP Pavilion Mini is a budget-friendly mini PC that can give your dumb TV a complete overhaul for about $320.
It’s powered by a 1.7GHz dual-core Intel Pentium 3558U processor and 4GB of RAM. It also has a 500GB SATA drive for storage and Wi-Fi 802.11 b/g/n support. There are plenty of peripheral ports too such as a DisplayPort, HDMI, USB 3.0, Ethernet, 3.5mm audio, and an SD card slot. It even comes with a wireless mouse and keyboard.
Why is all of this relevant? Again, you can connect this affordable Windows desktop to your TV and effectively turn it into a “smart” TV complete with Internet access and streaming capabilities. Since it’s essentially a slimmed down desktop, you’ll be afforded much more functionality than if you were to go with a set-top box like the Chromecast or something similar.
Even better, you have the option of customizing the experience; meaning you can tailor it to meet your needs. If you want to install something like Kodi — previously named XBMC — and completely transform your TV into a digital multi-media center you can do just that.
The Asus Chromebox offers
something a little different. Instead of a desktop running Windows,
you’re getting a system powered by Google’s Chrome OS.
It’s important to note that with the Chrome OS everything is essentially done within a browser window. If that’s a turn-off to you then take a look at one of the other mini PCs on this list.
There are three models to choose from: one packing an Intel Celeron dual-core processor with 2GB of RAM, another with an Intel Core i3 processor and 4GB of RAM, and much more powerful variant with an Intel Core i7 processor and 4GB of RAM. Other than the 4K video support for the Core i3 and i7 models there’s really no reason to pick up one of those as a consumer. The added power won’t do much when working with the Chrome OS. Not to mention you can always upgrade the available RAM later by adding more.
Additional features include Bluetooth 4.0, Wi-Fi 802.11 b/g/n, and a bundled keyboard and mouse; wireless or wired, your choice. There are a plethora of ports such as a DisplayPort, HDMI, Ethernet, 3.5mm audio, USB 3.0, and an SD card slot.
If you’ve ever used a Chromebook before then you’ll feel right at home with the Chromebox. If not, you might want to do a bit of research on the Chrome OS before making the leap. Still, it’s a great system especially if you want to turn your boring old TV into something much more accessible.
If you’re partial to Apple products and would much rather have a slimmed down system running OS X, then the Apple Mac Mini is
the way to go. It’s quite a bit more expensive than some of the other
PCs on this list, starting at $499. Depending on the features you
choose, it may be as high as $999.
Like the other mini PCs on this list, it’s a compact, portable desktop that you can connect to any display and turn “smart”. It comes with the keyboard and mouse you’ll need to operate the system, so no worries there. In fact, it comes with everything you need right out of the box.
The cheapest model is powered by a 1.4GHz dual-core Intel i5 processor and 4GB of DDR3 RAM. It’s also packing an Intel HD Graphics 5000 chipset and a 500GB hard drive for storage.
All you need to do is plug it into a display and you’re off! It’s essentially like taking a Mac — laptop or desktop — and hooking it up to your living room TV. You can browse the web, watch videos, play music, play games, and much more. Since it’s running OS X Yosemite, you even have access to Apple’s robust selection of applications including Photos, iMovie, GarageBand, Pages, Numbers, and Keynote.
You can’t go wrong with this one.
Not a fan of Windows, Mac OS X, or Chrome OS? No problem! Take a look at the Mintbox Mini, a lightweight, portable computer running the Linux Mint distro.
For hardware, it includes an AMD A4 6400T quad-core processor, 4GB of RAM, and Radeon R3 graphics out of the box. In addition, it has a 64GB solid state drive for storage. What does all of this mean in layman’s terms? If you’re a layman you’re probably not going with a Linux machine, but that’s OK, we’ll indulge you anyway.
The Mintbox Mini is more than capable of handling HD video playback, web browsing, productivity tasks, and software applications. For connectivity, it offers HDMI, 3.5mm audio, microSD, and USB 3.0. Of course, it has an Ethernet port and Wi-Fi 802.11 b/g/n support, as well. The most impressive feature is that the processor is passively cooled, which means the Mintbox is virtually silent.
It’s $295, with a portion of the sales used to fund Linux Mint development, and it comes with a 5-year warranty.
If you’re looking for something ridiculously small and lightweight, then you might want to consider the Zotac Zbox Pico. The case for the Pico measures only 4.6 x 2.6 x 0.8 inches. To spell it out for you, this little guy can fit in your pocket.
It’s running Windows 8.1 out of the box and has some pretty solid hardware inside for such a small device. An Intel Atom quad-core processor and 2GB DDR3 RAM power this thing, with Intel HD graphics and 32GB of internal storage. Then there’s USB 2.0, microSD, Ethernet, and HDMI ports. Top it all off with Bluetooth 4.0 and Wi-Fi 802.11n wireless connectivity and you’ve got yourself a decent little rig.
Sadly, it doesn’t come bundled with a keyboard and mouse so you’ll need to lug those around with you if you don’t have them handy. Still, this thing is such a great way to get your dumb TV hooked up to the Internet and streaming content. You might even throw it in your pocket and take it to a friend’s to make their dumb TV smarter for the evening.
Source: promos.asus.com
You can always purchase a set-top device like Roku, Google Chromecast, Apple TV, or even the Amazon Fire TV. However, these devices have limitations on what type of content or media they can stream. It would be much more beneficial to connect a computer or PC to your TV. Then you can stream all kinds of media, but you can also browse the Internet, play games, and run applications.
Nobody wants a large tower sitting beside their TV, though, and laptops tend to look silly, and, really, they’re only temporarily useful in this regard. Who wants a messy console or entertainment system with wires protruding everywhere?
That’s where Mini PCs or HTPCs come into play.
1. HP Pavilion Mini
Source store.hp.com
It’s powered by a 1.7GHz dual-core Intel Pentium 3558U processor and 4GB of RAM. It also has a 500GB SATA drive for storage and Wi-Fi 802.11 b/g/n support. There are plenty of peripheral ports too such as a DisplayPort, HDMI, USB 3.0, Ethernet, 3.5mm audio, and an SD card slot. It even comes with a wireless mouse and keyboard.
Why is all of this relevant? Again, you can connect this affordable Windows desktop to your TV and effectively turn it into a “smart” TV complete with Internet access and streaming capabilities. Since it’s essentially a slimmed down desktop, you’ll be afforded much more functionality than if you were to go with a set-top box like the Chromecast or something similar.
Even better, you have the option of customizing the experience; meaning you can tailor it to meet your needs. If you want to install something like Kodi — previously named XBMC — and completely transform your TV into a digital multi-media center you can do just that.
2. ASUS Chromebox
Source: promos.asus.com
It’s important to note that with the Chrome OS everything is essentially done within a browser window. If that’s a turn-off to you then take a look at one of the other mini PCs on this list.
There are three models to choose from: one packing an Intel Celeron dual-core processor with 2GB of RAM, another with an Intel Core i3 processor and 4GB of RAM, and much more powerful variant with an Intel Core i7 processor and 4GB of RAM. Other than the 4K video support for the Core i3 and i7 models there’s really no reason to pick up one of those as a consumer. The added power won’t do much when working with the Chrome OS. Not to mention you can always upgrade the available RAM later by adding more.
Additional features include Bluetooth 4.0, Wi-Fi 802.11 b/g/n, and a bundled keyboard and mouse; wireless or wired, your choice. There are a plethora of ports such as a DisplayPort, HDMI, Ethernet, 3.5mm audio, USB 3.0, and an SD card slot.
If you’ve ever used a Chromebook before then you’ll feel right at home with the Chromebox. If not, you might want to do a bit of research on the Chrome OS before making the leap. Still, it’s a great system especially if you want to turn your boring old TV into something much more accessible.
3. Apple Mac Mini
Source: apple.com
Like the other mini PCs on this list, it’s a compact, portable desktop that you can connect to any display and turn “smart”. It comes with the keyboard and mouse you’ll need to operate the system, so no worries there. In fact, it comes with everything you need right out of the box.
The cheapest model is powered by a 1.4GHz dual-core Intel i5 processor and 4GB of DDR3 RAM. It’s also packing an Intel HD Graphics 5000 chipset and a 500GB hard drive for storage.
All you need to do is plug it into a display and you’re off! It’s essentially like taking a Mac — laptop or desktop — and hooking it up to your living room TV. You can browse the web, watch videos, play music, play games, and much more. Since it’s running OS X Yosemite, you even have access to Apple’s robust selection of applications including Photos, iMovie, GarageBand, Pages, Numbers, and Keynote.
You can’t go wrong with this one.
4. Mintbox Mini
Source: fit-pc.com
For hardware, it includes an AMD A4 6400T quad-core processor, 4GB of RAM, and Radeon R3 graphics out of the box. In addition, it has a 64GB solid state drive for storage. What does all of this mean in layman’s terms? If you’re a layman you’re probably not going with a Linux machine, but that’s OK, we’ll indulge you anyway.
The Mintbox Mini is more than capable of handling HD video playback, web browsing, productivity tasks, and software applications. For connectivity, it offers HDMI, 3.5mm audio, microSD, and USB 3.0. Of course, it has an Ethernet port and Wi-Fi 802.11 b/g/n support, as well. The most impressive feature is that the processor is passively cooled, which means the Mintbox is virtually silent.
It’s $295, with a portion of the sales used to fund Linux Mint development, and it comes with a 5-year warranty.
5. Zotac Zbox Pico
Source: zotac.com
It’s running Windows 8.1 out of the box and has some pretty solid hardware inside for such a small device. An Intel Atom quad-core processor and 2GB DDR3 RAM power this thing, with Intel HD graphics and 32GB of internal storage. Then there’s USB 2.0, microSD, Ethernet, and HDMI ports. Top it all off with Bluetooth 4.0 and Wi-Fi 802.11n wireless connectivity and you’ve got yourself a decent little rig.
Sadly, it doesn’t come bundled with a keyboard and mouse so you’ll need to lug those around with you if you don’t have them handy. Still, this thing is such a great way to get your dumb TV hooked up to the Internet and streaming content. You might even throw it in your pocket and take it to a friend’s to make their dumb TV smarter for the evening.
More from Gear & Style Cheat Sheet:
Wednesday, October 14, 2015
Homo sapiens arrived in China before Europe, study of 47 teeth shows
http://www.latimes.com
The findings, published in the journal Nature, may compel researchers to reconsider the current view of human migrations out of Africa — and could hint that Neanderthals may have been a much greater barrier to Europe than previously thought.
"I really think it’s opening a new period of understanding and more creative thinking about the other possibilities of long-established models," said paleoanthropologist María Martinón-Torres of University College London, who co-led the study with Wu Liu and Xiu-jie Wu of the Chinese Academy of Sciences.
See the most-read stories in Science this hour >>
Scientists believe that Homo sapiens first emerged in East Africa somewhere between 190,000 and 160,000 years ago, spread into the eastern Mediterranean around 100,000 to 60,000 years ago but then were replaced by Neanderthals after that, according to Robin Dennell of the University of Exeter, who was not involved in the paper.
The successful dispersal westward into Europe would not have come until much later, around 40,000 years ago. And scientists think that our species didn’t trek eastward until around 60,000 years ago, an idea based on some genetic estimates as well as on the similarities between stone tools in South Africa dated to 60,000 years ago and some in South Asia from 36,000 to 30,000 years ago.
Paleoanthropologists have looked to the karst caves in southern China that are full of fossils, but it has been hard to pin down a date on the specimens gathered — or even to tell which hominid species the fossils belong to.
Fuyan Cave in Hunan province, where these teeth were found, has an ideal mix of features that allowed scientists to pin down the fossils’ age. (Teeth often are the best-preserved remains in an acidic environment like a karst cave because enamel is the hardest tissue in the human body, and dentin, while not quite as hard, is still harder than bone.)
For such fossils, understanding their context — where they were located, how deep they were buried — is vital because each layer of rock represents a different epoch in time. The deeper the objects were found, the older they are. So if those layers are disturbed in any way, it becomes very difficult for excavators to tell the true age of those fossils.
Luckily, in Fuyan Cave, a layer of flowstone had grown over the layer that held the human teeth, sealing them in and preventing them from being disturbed. Over the flowstone grew a stalagmite, which was dated to at least 80,100 years old — which means all the material below it, teeth included, must be older.
Beneath the flowstone, the scientists also found mammalian fossils from 38 species as well as five extinct large mammals, including Stegodon orientalis (a relative of mammoths and elephants) and Ailuropoda baconi (an ancestor of the giant panda). These animals must have come from a period of time known as the Upper Pleistocene, about 125,000 to 10,000 years ago.
Together, the stalagmite and the mammalian fossils allowed researchers to put an upper limit on the age of the human teeth. Their owners must have lived sometime between 80,000 and 120,000 years ago.
Taken together, these teeth look remarkably like those of contemporary humans; they’re smaller and smoother than those of earlier human species, such as Homo erectus.
“The fact that the teeth resemble those of Upper Pleistocene Europeans and modern humans implies that the population they came from were immigrants and not the outcome of local evolution from H. erectus,” Dennell wrote in a commentary on the study. “To place these finds in their continental context, the Fuyan teeth indicate that modern humans were present in southern China 30,000 to 60,000 years earlier than in the eastern Mediterranean and Europe.”
That’s a pretty big difference between the two populations, and it could hint that our relatives the Neanderthals could have been the reason that Homo sapiens failed to break into the continent on their apparent first try. Before this, many thought that modern humans fairly quickly led to the demise of Neanderthals as they moved through Europe; but perhaps Neanderthals were a bigger block than previously believed.
“We should not rule out the possibility that H. neanderthalensis was for a long time an additional barrier for modern humans’ expansion, who could only settle in Europe when Neanderthal populations started to fade,” the study authors wrote.
There could be other explanations for the delay in getting to Europe, others said.
“The predominantly colder winter conditions of the enormous landmass between Europe and northern China may better explain the earlier colonization of southern zones,” Dennell wrote.
Either way, it opens up a lot of questions about whether, and how, this migration into southern China relates to the human population today,” Martinón-Torres said. Did these humans die out before being replaced with a later migration? Did they somehow mix with other African homo sapiens who later spread to other continents?
“We really have a lot of new questions about the origin of current populations. ... I think it’s an exciting period, in that sense,” she said.
Monday, October 12, 2015
Box Office: How 'Pan' Turned Into an Epic Flop
The Hollywood Reporter
October 12, 2015
‘Pan’ (Warner Bros. Pictures)
By Pamela McClintock, The Hollywood Reporter
Early on in Pan, a young Peter Pan asks “where’s the bacon” when being served a watery bowl of gruel at an orphanage in World War II London.
Little did British director Joe Wright and Warner Bros. know how prophetic the question would become.
Over
the weekend, the ambitious Peter Pan origin story bombed at the North
American box office, grossing a paltry $15.5 million despite a $150
million production budget and a friendly PG rating. Pan, from
Warner Bros. and co-financing partner RatPac-Dune Entertainment, could
lose more than $100 million unless the live-action movie does huge
business overseas, a tough proposition.
The
film took in $20.5 million this weekend internationally from 52 markets
representing 40 percent of the foreign marketplace, putting its early
global total at a worrisome $40.6 million (it opened in Australia two
weekends ago). One hope is China, where Pan rolls out Oct. 22. So far, it is doing best in Latin America, while struggling in Europe.
Wright’s
grand plan for his trip to Neverland didn’t pan out. The lucrative
family audience rejected the live-action film, starring Hugh Jackman,
Rooney Mara, Garrett Hedlund, newcomer Levi Miller and plenty of special
effects. It’s another blow for the leadership at at Warners, which has
suffered a string of misses this year, including pricey titles Jupiter Ascending and The Man from U.N.C.L.E.
The studio declined comment on Pan’s
performance, but one Warners executive said, “it came in so much
lighter than anything we could have predicted. The movie failed to bring
in an audience of any size.”
Only 23 percent of Pan’s audience was under the age of 18. As a way of comparison, 44 percent of ticket buyers going to see Disney’s live-action Cinderella earlier this year were under the age of 18.
Females, and especially younger females, fueled hits like Cinderella and Disney’s Maleficent. Femmes made up 77 percent of Cinderella’s audience on opening weekend and 60 percent of Maleficent ticket buyers. This demo were less keen to see Pan, making up 55 percent of the audience.
Leading up to its release, Pan
was ravaged by critics. Some reviewers described it as a sort ofIndiana
Jones meets Avatar, with Jackman’s Blackbeard compared to the villain
in Mad Max: Fury Road. And Wright’s decision to have Blackbeard
and his gang of pirates sing Nirvana’s “Smells Like Teen Spirit” was
heavily debated. Pan is the first studio tentpole directed by Wright, known for speciality fare like Atonement and Pride and Prejudice.
“Reboots
are always tricky,” said box-office analyst Phil Contrino. “There’s
always the risk that fans of a property won’t be in tune with the new
vision and that seems to be what has happened here.”
Adds a rival studio executive, “Pan is neither fish nor fowl. It’s trying to be too many things.”
The
film also sparked controversy when Wright chose Mara, instead of a
Native American actress, to play Tiger Lily, prompting a petition urging
Warner Bros. to stop casting white actors as people of color.
“Tough
reviews, a change of release date and other factors conspired to create
this opening weekend performance. Certainly, while the origin story
concept in and of itself is not a bad thing, audiences may have had
trouble grasping the concept of the film,” said Paul Dergarabedian of
Rentrak. “The silver lining may come in the international theatrical
marketplace and of course down the road on home video where curious
audiences may want to check out the film and have additional in home
content for their kids.”
Pan
was originally set to open this past July, but a worried Warners
delayed its release to fall, presumably a quieter corridor. The movie
had tested poorly, and the studio wanted to do reshoots. But that plan
didn’t quite work out.
Related: 'Pan’: Film Review
Dergarabedian and Contrino cite competition from holdovers The Martian and Hotel Transylvania 2 as another reason Pan got destroyed. Over the weekend, 10 percent of The Martian’s audience was under the age of 18, proof that families are turning out to see the space epic, starring Matt Damon. And Hotel Transylvania 2 is a natural draw for younger kids.
For Hotel Transylvania 2 to beat Pan in its third weekend, both domestically and internationally, is a stinging blow.
“Following the huge success of Hotel Transylvania 2 wasn’t an easy task,” says Contrino. “And it definitely stole away some of the momentum Pan might have had.”
Friday, October 9, 2015
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