| Diamond (270) |  |
| Emerald (7) | |
| Gemstone (33) | |
| Pearl (6) | |
| Sapphire (18) | |
| Spinel (71) | |
| Turquoise (5) | |
or Jade Rabbit on board. China has made no secret of its designs on the Moon, with speculation that one of its citizens will walk on the surface within the next ten years.
Among the other countries, there has been some comment that China has collected a"string of pearls,
According to the GEM 2014 Global Report, an annual report on global entrepreneurship, nnovation-driven economieslike the U s. tend to have the greatest fear of failure and fewer aspiring entrepreneurs,
The first is a special Diamond Like Coating (DLC), which layers carbon on the pump,
In their experiments reported in the journal Science researchers measured the MRI signal with a novel diamond sensor chip using an optical readout in a fluorescence microscope.
The sensor consisted of an impurity in diamond known as the nitrogen-vacancy center. In this case two carbon atoms are missing in the otherwise regular diamond lattice
while one of them is replaced by a nitrogen atom. The nitrogen-vacancy center is both fluorescent and magnetic making it suitable for extremely precise magnetic field measurements.
For their experiment the researchers prepared an approximately 2×2 millimeter piece of diamond such that nitrogen-vacancy centers formed only a few nanometers below the surface.
#New nanothreads are like diamond necklaces Scientists say super-thin iamond nanothreadsould be stronger and stiffer than the strongest nanotubes
The core of the nanothreads is a long thin strand of carbon atoms arranged just like the fundamental unit of a diamond s structure zigzag yclohexanerings of six carbon atoms bound together in
as if an incredible jeweler has strung together the smallest possible diamonds into a long miniature necklacebadding says. ecause this thread is diamond at heart we expect that it will prove to be extraordinarily stiff extraordinarily strong
and to link up in a highly ordered chain of single-file carbon tetrahedrons forming these diamond-core nanothreads. adding s team is the first to coax molecules containing carbon atoms to form the strong tetrahedron shape then link each tetrahedron end to end to form a long thin nanothread.
The resulting diamond-core nanothread is surrounded by a halo of hydrogen atoms. During the compression process the scientists report the flat benzene molecules stack together bend
The result is a structure that has carbon in the tetrahedral configuration of diamond with hydrogens hanging out to the side and each tetrahedron bonded with another to form a long thin nanothread. t really is surprising that this kind of organization happensbadding says. hat the atoms
so that when we release the pressure very slowly an orderly polymerization reaction happens that forms the diamond-core nanothread.
arts of these first diamond nanothreads appear to be somewhat less than perfect so improving their structure is a continuing goal of Badding s research program.
He also wants to discover how to make more of them. he high pressures that we used to make the first diamond nanothread material limit our production capacity to only a couple of cubic millimeters at a time so we are not yet making enough of it to be useful on an industrial scalebadding says. ne of our science goals is to remove that limitation by figuring out the chemistry
necessary to make these diamond nanothreads under more practical conditions. he nanothread also may be the first member of a new class of diamond-like nanomaterials based on a strong tetrahedral core. ur discovery that we can use the natural
alignment of the benzene molecules to guide the formation of this new diamond nanothread material is really interesting
and DNA. ingle crystals are the backbone of many things we rely onâ##diamonds for beauty as well as industrial applications sapphires for lasers
-triggered brittle failures during the olivine-spinel (mineral) phase transformation has many similar features to deep earthquakes. ang
and undergoes a transformation resulting in spinel a mineral of higher density. he research team focused on the role that phase transformations of olivine might play in triggering deep earthquakes.
and found the arthquakesonly within a narrow temperature range that simulates conditions where the real earthquakes occur in Earth. sing synchrotron X-rays to aid our observations we found that fractures nucleate at the onset of the olivine to spinel transitiongreen says. urther these fractures propagate dynamically
The research team also included scientists at Fudan University in Shanghai, the Chinese Academy of Sciences and Diamond Light source.
Spectography is used often to identify gems, and CEO Dror Oren adds, f someone wants to offer an application for diamonds that costs $1, 000,
that the kind of platform we want to build. Other companies working in the portable spectrometer space have used also the technology to track calories eaten and nutritional intake through a user sweat.
#Discovery of water-containing gem points to vast oceans beneath the Earth The Earth transition zone is the part of the Earth that exists between the upper and lower mantle.
A group of geologists from the University of Alberta uncovered a water-containing gem that finally confirms this theory:
The tiny gem was an accidental find while the geologists were searching for a completely different mineral.
In fact, they very nearly discarded what appeared as a useless brown diamond (because that how geologists think of diamonds).
This diamond, though, turned out to hold ringwoodite, a mineral we have seen only previously in meteorites,
and not On earth. Fortunately, as with many scientific discoveries, this accident was a happy find.
Their final results showed that the gem contained 1. 5 percent of its weight in water.
is improving efficiency, security and productivity at a Canadian diamond mine. According to a company statement, the unnamed mining operation was facing a security challenge as its tools are utilised 24/7,
They did so by producing quantum bits using electrons trapped in diamonds at extremely low temperatures. These ultra-cold gemstones effectively acted as prisons trapping the electrons
and allowing the scientists to accurately establish their spin or value. If they can repeat the experiment over distances significantly larger than 10 feet it could mean that incomprehensibly fast quantum computers
#Diamond defects shrink MRI to the nanoscale Diamond-based quantum devices can now make nuclear magnetic resonance measurements on the molecular scale.
Both teams made diamonds with defects in their crystal structure#a single nitrogen atom next to a missing carbon atom, a few nanometres below the surface.
This gives the diamond a red fluorescent glow, which can be bright or dull depending on
Reinhard s team placed different kinds of samples onto their diamond and watched how the nuclear resonance in them influenced the spinning electrons in the nitrogen.
The idea would be to place a diamond crystal onto the tip of a scanning microscope,
Diamond nanocrystals immersed in a cell's cytoplasm could essentially produce real-time films of the activity of single molecules,
#Nanomaterial rivals hardness of diamond An article by Scientific American. It s only a matter of time before a movie villain pulling off the crime of the century needs a cutting tool that is harder than anything else On earth.
Perhaps it s a burglary that involves cutting into a case made of diamond#which,
a material that in many ways resembles diamond. Boron nitride can be compressed into a superhard, transparent form#but unlike diamond and many other materials known for their extreme hardness,
it is based not on carbon but on a latticework of boron and nitrogen atoms. Computer simulations have indicated that a rare crystalline form of boron nitride would resist indentation even better than diamond
if it could be synthesized into large samples, and laboratory experiments have shown that more attainable forms of the stuff already approach the hardness of diamond.
Now a new set of experiments on a nanostructured form of boron nitride have yielded even greater measures of hardness than before.
The new material exceeds that of some forms of diamond, according to the authors of a study reporting the findings in the January 17 issue of Nature.
so that they look like glass and diamond in appearance, Tian says. He and his colleagues determined that those samples had measured a hardness of up to 108 gigapascals#slightly harder than synthetic diamond
but less hard than polycrystalline diamonds made of nanoscale grains. But Natalia Dubrovinskaia, a crystallographer at the University of Bayreuth in Germany, notes that measuring the properties of superhard materials is problematic
gauges how a material responds to pressure from the point of a pyramid-shaped piece of diamond called an indenter.
As increasing force (as measured in newtons) is applied to the diamond pyramid, the material s ability to resist indentation levels off at its so-called asymptotic value (as measured in gigapascals).
But the test is predicated on the idea that the diamond will do the indenting, and not the other way around."
In some respects, such as stability at high temperatures, boron nitride is superior to diamond. More from Scientific American. As such, she notes,
Inspired by the idea that diamonds are made of carbon that has been subjected to high pressure, the company believes that transforming pollution into jewelry will prove desirable to many.
#Glowing diamonds make great thermometers Diamonds are known for many things: hardness, luster, and their reputation for being a irl best friend.
But the gems have important scientific uses, too. New research suggests that a certain type of artificial diamond can be used as a nanoscale temperature probe with unmatched precision over time
and space. think this work is a real advance, says materials scientist Daniel Jaque at the Autonomous University of Madrid,
who was involved not in the study. t a good paper on a hot topic. he tiny diamond probes can measure temperatures ranging from 120 K to 900 K (53°C to 627°C) s cold
Scientists discovered the properties of the probeseported in the current issue of Applied Physics Lettershen they set out to investigate a unique defect in diamonds grown using nickel precursors.
The technique incorporates some nickel atoms into the diamond crystal structure, forming what is called an 3 defect center.
Like many other diamond defects, the S3 center emits a glow when struck by a pulse of laser light.
As the temperature drops, the diamond glows for longer periods of time. Luminescent temperature probes aren a totally new idea,
here are many kinds of impurities in diamond, and this particular defect was the most interesting.
This difference makes the nickel-doped diamond luminescence extremely sensitive to fluctuations in temperature. Researchers say the diamond probes could be used for a wide range of applications
but Jaque suspects theyl be most useful for observing the nanoscopic world, in particular the minute temperature fluctuations in living cells.
since the visible light emitted by the diamond probes faint green glowoes not penetrate whole human tissue very well. nly infrared light can penetrate into your body.
Current techniques rely on growing diamonds with a nickel precursor and hoping the defects show up. e do not know how to prepare it.
We just collect it from many diamonds, and some of them have this effect. It a long path
but a more refined approach might allow researchers to standardize the size of diamond particles
#Largest laser gives diamond a record-setting squeeze Diamond has been subjected to the wrath of the world's largest laser
Chemical modelling suggests pressure deep inside the planets would crush it into a rain of diamond chips
and perhaps create chunks of diamond large enough to impress even the Kardashians. But until now no one had been able to replicate such pressures On earth
Our experiment provides the first actual data of diamonds under such high pressure says Ray Smith at the Lawrence Livermore National Laboratory in California.
Using the National Ignition Facility (NIF) at Livermore Smith's team bombarded tiny targets with 176 laser beams to put the squeeze on diamond.
The team fixed a diamond inside a hole cut in a small gold cylinder and then precisely timed laser pulses to strike the cylinder's interior walls.
During that short time the team was able to squeeze diamond to pressures of up to 5 terapascals about 50 million times the atmospheric pressure On earth's surface.
The team's data can now be used to improve models of gas giants and the suspected diamond in their depths.
Nikku Madhusudhan at the University of Cambridge says the results can also aid our understanding of the insides of diamond planets.
and may contain large layers of diamond. His team reported on models of such a world dubbed 55 Cancri e in October 2012.
#Scientists use'smallest possible diamonds'to form ultra-thin nanothreads For the first time scientists have discovered how to produce ultra-thin diamond nanothreads that promise extraordinary properties including strength and stiffness greater than that of today's strongest nanotubes
The core of the nanothreads that Badding's team made is a long thin strand of carbon atoms arranged just like the fundamental unit of a diamond's structure zigzag cyclohexane rings of six carbon atoms bound together in
It is as if an incredible jeweler has strung together the smallest possible diamonds into a long miniature necklace Badding said.
Because this thread is diamond at heart we expect that it will prove to be extraordinarily stiff extraordinarily strong and extraordinarily useful.
The team's discovery comes after nearly a century of failed attempts by other labs to compress separate carbon-containing molecules like liquid benzene into an ordered diamond-like nanomaterial.
and to link up in a highly ordered chain of single-file carbon tetrahedrons forming these diamond-core nanothreads.
The resulting diamond-core nanothread is surrounded by a halo of hydrogen atoms. During the compression process the scientists report the flat benzene molecules stack together bend
The result is a structure that has carbon in the tetrahedral configuration of diamond with hydrogens hanging out to the side and each tetrahedron bonded with another to form a long thin nanothread.
so that when we release the pressure very slowly an orderly polymerization reaction happens that forms the diamond-core nanothread.
The scientists confirmed the structure of their diamond nanothreads with a number of techniques at Penn State Oak ridge Arizona State university
Parts of these first diamond nanothreads appear to be somewhat less than perfect so improving their structure is a continuing goal of Badding's research program.
The high pressures that we used to make the first diamond nanothread material limit our production capacity to only a couple of cubic millimeters at a time so we are not yet making enough of it to be useful on an industrial scale Badding said.
One of our science goals is to remove that limitation by figuring out the chemistry necessary to make these diamond nanothreads under more practical conditions.
The nanothread also may be the first member of a new class of diamond-like nanomaterials based on a strong tetrahedral core.
Our discovery that we can use the natural alignment of the benzene molecules to guide the formation of this new diamond nanothread material is really interesting
or a scalpel so that the water can begin to penetrate between the Mos2 and the sapphire.
#An unlikely use for diamonds Tiny diamonds are providing scientists with new possibilities for accurate measurements of processes inside living cells with potential to improve drug delivery and cancer therapeutics.
Previous attempts by other research teams to visualise nanodiamonds under powerful light microscopes have run into the obstacle that the diamond material per se is transparent to visible light.
In their latest paper, researchers from Cardiff University's Schools of Biosciences and Physics showed that non-fluorescing nanodiamonds (diamonds without defects) can be imaged optically
and far more stably via the interaction between the illuminating light and the vibrating chemical bonds in the diamond lattice structure which results in scattered light at a different colour.
The team subjected wurtzite gallium arsenide to up to about 227000 times normal atmospheric pressure (23 gigapascals) in diamond anvil cells.
very low electrical resistance high thermal conductivity and mechanically stretchable yet harder than diamond. Now ORC researchers have developed molybdenum di-sulphide (Mos2) a similar material to graphene that shares many of its properties including extraordinary electronic conduction
and electricity it is transparent harder than diamond and extremely strong. But in order to use it to construct electronic switches a material must not only be an outstanding conductor it should also be switchable between on and off states.
such as precious opals, the colorful effects of the Lycurgus cup have little dependence on the position of the observer.
"We used microscopes similar to the ones jewelers use to see the clarity of precious gems.
which contains four tiny gold discs in a precise diamond-shaped arrangement. The gap in the center of the four discs is about 15 nanometers wide.
#Diamond plates create nanostructures through pressure not chemistry You wouldn't think that mechanical forcehe simple kind used to eject unruly patrons from bars,
"In our technology, two diamond anvils were used to sandwich nanoparticulate thin films. This external stress manually induced transitions in the film that synthesized new materials,
The pressure, delivered by two diamond plates tightened by four screws to any controlled setting, shepherds silver nanospheres into any desired volume.
but I ll see violet turquoise blue she said. It s like a mosaic of color.#
#Chinaâ#moon landing and rover tip of iceberg Yutu (Jade Rabbit#)China rover-like robot was landed soft on the moon earlier this month.
Team members are in the process of spinning out a product called Emerald that aims to detect, predict and prevent falls among the elderly.
In August the team presented Emerald to President Obama as part of the White house first annual Demo Day. n the same way that cellphones and Wifi routers have become indispensable parts
and avoid the segregation of Gd at the interface we have added an electronic conductor cobalt iron spinel (CFO),
Sekula said. 10 times as many Higgs particles means a flood of data to sift for gems LHC Run 2 will collide particles at a staggering 13 teraelectronvolts (Tev),
And with more Higgs, we'll have an easier time sifting the gems out of the gravel."
and even to make diamonds green and pearls black. A key accelerator parameter is the acceleration gradient,
#Microwave diamonds':'Girl's new best friend The 2. 62 carat diamond Calvin Mills bought his fiancee in November is a stunner.
Pear-shaped and canary-yellow, the gem cost $22, 000-a bargain. Mills, the chief executive officer of CMC Technology Consulting in Baton rouge, La.
says he could have spent tens of thousands more on a comparably sized diamond mined out of the earth,
but his came from a lab ."I got more diamond for less money, "says the former Southern University football player. who proposed last year at halftime during one of his alma mater's games at the Superdome in New orleans
. While man-made gems make up just a fraction of the $80 billion global diamond market, demand is increasing as buyers look for cheaper stones that are cheaper-and free of ethical taint.
Human-rights groups, with help from Hollywood have popularized the term"blood diamonds"to call attention to the role diamond mining has played in fuelling conflicts in Africa.
Unlike imitation diamonds such as cubic zirconia, stones that are grown"(the nascent industry's preferred term) in labs have the same physical characteristics and chemical makeup as the real thing.
They're made from a carbon seed placed in a microwave chamber with methane or another carbon-containing gas and superheated into a glowing plasma ball.
That creates particles that crystallize into diamonds, a process that can take 10 weeks. The technology has progressed to the point that experts need a machine to tell synthesized gems apart from those extracted from mines or rivers.
North american consumers from 18 to 35 who say they prefer natural and untreated diamonds: 45%Retailers, including Wal-mart Stores
and Warren Buffett's Helzberg Diamonds are beginning to stock the artificial gems.""To a modern consumer,
if they get a diamond from above the ground or in the ground, do they really care?"
"asks Chaim Even-Zohar, a principal at Tacy, an industry consulting firm in Ramat Gan, Israel.
In a survey by Gemdax, an Antwerp-based consultant, only 45%of North american consumers from 18 to 35 said they prefer natural diamonds."
"Some substitution for natural diamonds is inevitable, "says Anish Aggarwal, a partner at the firm,
The companies that dominate the market for natural gems, including Russia's Alrosa and De beers,
says Neil Koppel, the CEO of Renaissance Diamonds. His company, in Boca raton, Fla. is supplying Helzberg stores in 10 US cities.
Last year only about 3, 60,000 carats of man-made diamonds were produced, compared with 146 million carats of natural gems mined in 2013, estimates researcher Frost & Sullivan.
The Supply of lab-grown stones will probably jump to 2 million carats in 2018 and 20 million by 2026."
"The value of a diamond is linked inextricably to the inspirational and unique narrative that lies behind each one, from its formation to its history to its emotional significance,
which lab-grown diamonds simply don't have said, "the company. in a statement. In July, mining companies won a major marketing victory when the International organization for Standardization ruled that man-made gems must be called synthetic, lab-grown,
or lab-created-not real, cultivated, or cultured d
#People could use breath to'speak'LONDON: A first of its kind device that transforms paralysis victims'breath into words has been developed by researchers,
#Geometrically Encoded Magnetic Sensors (GEMS) for High-resolution Remote Biological Sensing To date, most efforts to image highly localized biochemical conditions such as abnormal ph
The novel devices, called geometrically encoded magnetic sensors (GEMS), are microengineered metal-gel sandwiches about 5 to 10 times smaller than a single red blood cell, one of the smallest human cells.
and the change over time was sensed by the GEMS and recorded through real-time shifting in resonant frequencies.
which GEMS can be employed for biomedical uses.""That would require, among other things, further miniaturization.
The 0. 5 to 2 m diameter GEMS in the experiments are already small enough for many in vitro and other possible non-biological applications,
One of the most significant features of GEMS is that they can be tuned"in fabrication to respond to different biochemical states
respectively So placing two different populations of GEMS at the same site makes it possible to track changes in two different variables at the same time--a capability the researchers demonstrated by placing GEMS with two different dimensions in the same location and detecting
Functionally, the GEMS in the current effort are advanced more in that they change their shape in response to stimuli;
The researchers used a single-point diamond-turning lathe to fabricate the part of the microscope called the objective
the researchers used a single-point diamond turning lathe. The lenses were enclosed then in an all-plastic, 3d printed microscope housing and objective.
the researchers used a single-point diamond turning lathe. The lenses were enclosed then in an all-plastic, 3d printed microscope housing and objective.
The team tested the material by scratching it with stainless steel tweezers, screwdrivers, diamond-tipped scribers,
#Umbrella-shaped diamond nanostructures make efficient photon collectors Standard umbrellas come out when the sky turns dark,
Inspired by recent work to enhance the luminescence from diamond nanopillar structures, a team of researchers in Japan has discovered that"umbrella-shaped"diamond nanostructures with metal mirrors on the bottom are more efficient photon collectors than their diamond nanostructure"cousins"of other shapes.
By tweaking the shape of the diamond nanostructures into the form of tiny umbrellas, researchers from Tokyo Institute of technology experimentally showed that the fluorescence intensity of their structures was three to five times greater than that of bulk diamond.
They report their results in the journal Applied Physics Letters, from AIP Publishing. To get started, the team formed the umbrella-shaped diamond nanostructures by using an original"bottom-up"fabrication technique that relies on selective and anisotropic growth through holes in a metal mask.
The metal mask also serves as a mirror that is self-aligned to the diamond nanostructures."
"Our umbrella-shaped nanostructure has an effect similar to a solid immersion lens, which reduces the chance of total reflection on its upper surface
and focuses the emitted light toward the'upside'of the structure, "explained Mutsuko Hatano, a professor in the Graduate school of Science and Engineering's Department of Physical Electronics at Tokyo Institute of technology.
"Umbrella-shaped diamond provides significantly better photon collection efficiency than bulk diamond or its pillar-shaped diamond counterpart,
The significance of the team's discovery is that they've shown that the brighter fluorescence intensity of umbrella-shaped diamond nanostructures can be achieved by improving the photon collection efficiency of the nitrogen vacancy centers,
which are the numerous point defects in diamonds that happen to boast the property of photoluminescence.
These properties make nitrogen vacancy centers in diamonds candidates for next-generation spin-based quantum devices such as magnetometers, quantum computers,
Due to the high refractive index (2. 4) of diamond, the photon collection efficiency from the nitrogen vacancy centers in bulk diamond is low."
"In other words, diamond works as an effective light waveguide in low-refractive-index environments,"said Hatano. In terms of applications, the team's nanostructures may find use in highly sensitive magnetic sensors for making biological observations or within the computational science realm for quantum computing and cryptographic communications.
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