#A Huge Burst Of Gamma rays Hit Earth--And No one Noticedlast year Japanese scientists found evidence that in 775 AD Earth was hit with a sudden blast of high-intensity radiation--a blast
instead in the amount of radioactive carbon trapped in the annual growth rings of some of the world's oldest trees.
Carbon's key radioactive isotope carbon-14 forms when energetic particles enter Earth's atmosphere
So what could have caused the massive burst of radiation and the high influx of energetic particles that led to the elevated levels of carbon-14 in the atmosphere?
The radiation either came from an especially intense solar flare or the explosion of a nearby star.
Second--and perhaps more importantly--such flares would also have destroyed the Earth's ozone layer exposing all of life to harsh radiation
A nearby supernova would have sent gamma rays flying in all directions. Those rays would have created high-energy particles in our atmosphere
which could then go on to form the carbon-14 present in such abundance in the Japanese cedars.
But in order to send out enough gamma rays to do the trick the supernova would have had to be bigger and brighter than other historical bright spots that were documented in fact.
a short-duration gamma ray burst produced by the collision of two nearby neutron stars. Though immensely powerful (we're talking two 10-mile wide boulders each with the mass of our sun) the collision would only have been visible from Earth for about a day
So the formation of radioactive isotopes isn't a steady process? This could cause us to change our assumptions about dating methods.
There are various calibration curves to account for the varying presence of solar radiation and other known sources.
The reason they would assume the event to be recorded is most likely because of the chinese astronomers.
For many hundred years the chinese governement had a large number of clerks dedicated to astronomy.
or radical drop in the magnetic field of local pottery from that time as well correct? 4. 54 Billion Earth has been here. 3000 years is such a tiny gap of time lol. soy sauce was reported first being used in Japan in 775:@
and into a chute repelled by the magnetic field. Everything else falls into a different chute.
It was an epiphany says Vaneck who works for the Massachusetts research and development company Physical sciences Inc. PSI.
But until recently inventors lacked the aerodynamics expertise to turn diagrams into mechanical versions of something as quotidian as a fly or a bee.
Although insects and their relatives represent roughly 80 percent of the world s animal species ome 900000 known types he mechanics of their flight had long been an enigma.
And the stubby wings of bees and other insects lift far more weight than can be explained using conventional steady-state aerodynamics principles.
so that as it flapped he could analyze the fluid dynamics. At the University of California at Berkeley neurobiologist Michael Dickinson built a robotic fruit-fly wing that likewise mimicked a fly s natural motion
Working independently the researchers characterized the aerodynamics of flight with unprecedented specificity. Dickinson and electrical engineer Ron Fearing won a $2. 5-million DARPA grant in 1998 to apply these principles to a fly-size robot.
which aerodynamics insights the students should try to reproduce. Flies have really complex wing trajectories.
other researchers have used flapping-wing dynamics to reduce the size of aerial vehicles capable of carrying payloads.
The Techject Dragonfly takes advantage of an aerodynamics principle called resonance. When wings flap at their most efficient frequency hich happens
But within milliseconds the fly s center of gravity appeared to pull the fly back into a stable position.
Now the biologists use cameras that can run at 7500 frames per second significantly higher than what was once available to researchers and that work in infrared light.
Nondestructive imaging of ancient fossilsby integrating high-resolution X-ray imaging (termed microct) 3d image segmentation and computer animation a new study conducted by Carole Gee at the University of Bonn Germany demonstrates the visualization of fossils without destroying the material.
Using this technique X-ray images similar to those used in the medical field are captured providing virtual cross-sections of the specimen without ever cutting into the sample.
For films with no GNRS the pressure dropped to zero in about 100 seconds as nitrogen escaped into the vacuum chamber.
The comparison involved a 2011 Smith Newton electric truck powered by a 120 kw electric motor
Halas Rice's Stanley C. Moore Professor in Electrical and Computer Engineering professor of physics professor of chemistry and professor of biomedical engineering is one of the world's most-cited chemists.
and radiation and show promise for stacking in three-dimensional arrays. Rudimentary silicon memories made in the Tour lab are now aboard the International Space station where they are being tested for their ability to hold a pattern
when exposed to radiation. The diodes eliminate crosstalk inherent in crossbar structures by keeping the electronic state on a cell from leaking into adjacent cells Tour said.
Douglas Natelson a professor of physics and astronomy and of electrical and computer engineering and Krishna Palem the Ken and Audrey Kennedy Professor of Computer science and Electrical and Computer Engineering and a professor of statistics.
Yakobson a theoretical physicist and his team specialize in analyzing the interplay of energy at the atomic scale.
The expansion will mark Jove's eighth journal section after the recent additions of Jove Chemistry and Applied Physics.
the optical measurements were carried out in the Tony Heinz lab in physics. The structural modeling and electronic structure calculations were performed by the David Reichman lab in chemistry.
The electron microscopy was performed by atomic imaging experts in the David Muller lab at Cornell University's School of Applied and Engineering Physics and the Kavli Institute at Cornell for Nanoscale Science.
The new technology has been shown to nearly eliminate the reflection losses of solar radiation. Cost-effective solar photovoltaic materials are being developed within the Academy of Finland's research programme Photonics and Modern Imaging Techniques.
The nanostructured black silicon coating features very low reflectivity meaning that a larger portion of the Sun's radiation can be exploited.
Instead they use the kinetic energy of flowing stream water to power the lifting of a fraction of this water to a higher elevation.
when activated by weak ultraviolet light. By keeping the intensity of the UV light sufficiently low researchers can photoactivate individual proteins to image them
Within 25 years practically no ash trees may remain on either side of the St lawrence Seaway said Akhlesh Lakhtakia Charles Godfrey Binder Professor of Engineering science and Mechanics at Penn State.
) This research was supported by the U s. Air force Office of Scientific research Multidisciplinary University Research Initiative by the UK Engineering and Physical sciences Research Council and through a postdoctoral research fellowship from the Alexander Von humboldt Foundation.
and department chair of physics and astronomy at Rice. This is the first time anyone has arranged these four cell types in the same way that they are found in lung tissue.
In the lab you are just seeing part of the process of root growth said Bucksch who works in the group of Associate professor Joshua Weitz in the School of Biology and School of Physics at Georgia Tech.
whereas an infrared camera was able to detect inflammatory alterations in the udder four hours after the inflammation had set in says Jutta Kauppi.
Specifically we coated a dead female beetle with a vapor of nickel and used the'nickelized'shell to fabricate two matching molds in the shape of a resting beetle said Akhlesh Lakhtakia Charles Godfrey Binder professor of engineering science and mechanics
Wildland fires involve complex interactions that include fuel distribution terrain topography chemical reactions energy transfer and the associated fluid dynamics that transport moisture gas-phase hydrocarbons air
burns to help develop models describing the chemistry and fluid dynamics of fires. His interest was sparked.
what is going to dictate the fluid dynamics in the vicinity. In turn the fluid dynamics of the air and combustible hydrocarbons as fire progresses could point the way to where the fire will spread.
The process begins with pyrolysis the thermochemical decomposition of organic material at elevated temperature Dr. Mahalingam says.
and the resulting fluid dynamics will in turn drive the fire. Continual warming of the leading edge of the fire is a necessary precondition to releasing the chemicals in the fuels that are needed to sustain it.
Because it's so easy to accidently introduce impurities into graphene labs led by physicists Junichiro Kono of Rice
Hitting the combined material with femtosecond pulses from a near-infrared laser prompted the indium phosphide to emit terahertz back through the graphene.
Imperfections as small as a stray oxygen molecule on the graphene were picked up by a spectrometer.
Not just the intensity but also the waveform of emitted terahertz radiation totally and dynamically changes in response to molecular adsorption and desorption.
Laser pulses generated coherent bursts of terahertz radiation through a built-in surface electric field of the indium phosphide substrate that changed due to charge transfer between the graphene and the contaminating molecules.
and functions of nanomaterialsby â#drawingâ##micropatterns on nanomaterials using a focused laser beam scientists could modify properties of nanomaterials for effective applications in photonic and optoelectric applications.
Through the use of a simple efficient and low cost technique involving a focused laser beam two NUS research teams led by Professor Sow Chorng Haur from the Department of physics at the NUS Faculty of science demonstrated that the properties of two
Instead of focusing sunlight we can focus laser beam onto a wide variety of nanomaterials and study effects of the focused laser beam has on these materials. â#Micropatterns â#drawnâ##on Mos2 films could enhance electrical conductivity
and photoconductivitymolybdenum disulfide (Mos2) a class of transition metal dichalcogenide compound has attracted great attention as an emerging two-dimensional (2d) material due to wide recognition of its potential in and optoelectronics.
and their team members utilised an optical microscope-focused laser beam setup to â#drawâ##micropatterns directly onto large area Mos2 films as well as to thin the films.
With this simple and low cost approach the scientists were able to use the focused laser beam to selectively â#drawâ##patterns onto any region of the film to modify properties of the desired area unlike other current methods where the entire film is modified.
and photoconductivity of the modified material had increased by more than 10 times and about five times respectively.
Hidden images â#drawnâ##by focused laser beam on silicon nanowires could improve optical functionalitiesin a related study published in the journal Scientific Reports on 13 may 2014 Prof Sow led
The team scanned a focused laser beam rapidly onto an array of mesoporous silicon nanowires which are packed closely like the tightly woven threads of a carpet.
They found that the focused laser beam could modify the optical properties of the nanowires causing them to emit greenish-blue fluorescence light.
Their understanding enabled them to â#drawâ##a wide variety of micropatterns with different optical functionalities using the focused laser beam.
To develop materials with properties that can cater to the industryâ##s demands Prof Sow together with his team of researchers will extend the versatile focused laser beam technique to more nanomaterials.
and Wildlife Acoustics Inc. The European nightjar for example is only active at night and is camouflaged very well making it difficult to detect using traditional survey methods.
And because our devices use silicon oxide--the most studied material On earth--the underlying physics are understood both well
and radiation as well as elements that enable wireless connectivity between the greenhouse and mobile devices like cell phones.
and keep the corn cubs for food we have come a long way says Per Morgen professor at the Institute of Physics Chemistry and Pharmacy University of Southern Denmark.
The research team investigated adaptive radiation--the explosive evolution of species into new ecological niches powered by natural selection--of New world Leaf-nosed bats.
This kind of engineering model may illuminate many other adaptive radiations and the origin of so much diversity On earth.
and most recently at Columbia University where he's now an associate professor of biological sciences and physics.
Sahin collaborated with Wyss Institute Core Faculty member L. Mahadevan Ph d. who is also the Lola England de Valpine professor of applied mathematics organismic and evolutionary biology and physics at the School of engineering and Applied sciences
valos of Stony Brook University and support from the National Science Foundation studied the evolutionary histories of the adaptive radiation of New world leaf-nosed bats based on their dietary niches.
As the authors point out adaptive radiations that is the explosive evolution of species into new ecological niches have generated much of the biological diversity seen in the world today.
Back in 1992, physicist and author Gregory Benford of the University of California, Irvine, published Saving the'library of life'in Proceedings of the National Academy of Sciences.
Logan Ward reports for Popular Mechanics: On September 28, 2010, the Federal Aviation Administration issued a Light Sport Aircraft certificate for the Maverick Sport,
. so he can use the portable spectrometer to test for chemicals used to simulate aging.
and other radioactive elements not commonly found in nature thanks to our nuclear weapons testing. And we have created some new compounds that will be in the geologic record for a long time to come, the most ubiquitous
To demonstrate, Australian researchers made a Bose-Einstein condensate (BEC) of rubidium atoms. A BEC is a substance that occurs
But a person can t just eat a radioactive chemical and hope to be healthy,
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