"This paper opens up the possibility that the standard of mass can be redefined in term of an atomic quantity instead of a lump of metal,
Molecular machines inspired by biology could eventually enable chemists to build materials with a specific sequence of molecules#a strand of polystyrene in which each component bears one of a range of extra chemical groups, for example.
The device is sensitive enough to pick up a signal even from materials that are barely luminescent, such as metals.
and troughs of the wave travel through the material#is so fast that it is travelling effectively in a vacuum, the explanation for the material s overall refractive index of zero (E.#J.#R.#Vesseur et al.
They then stuck the peptide to commercially available polystyrene nanobeads. The beads also carried a dye
or a polymer that hardens#either naturally or after being sintered by a laser#into a particular structure.
So-called"bioprinters naturally use cells rather than plastics to create organic structures. However this technique can damage the printed cells,
#Taking the crystals out of X-ray crystallography The technique that revealed DNA's double helix
A method described in Nature this week1 makes X-ray crystallography of small molecules simpler, faster and more sensitive,
largely doing away with the laborious task of coaxing molecules to form crystals. Instead, porous scaffolding holds molecules in the orderly arrangement needed to discern their structure with X-rays.
You could call it crystal-free crystallography, says Jon Clardy, a biological chemist at Harvard Medical school in Boston,
X-ray crystallography is one of the most important techniques in science, because it is one of only a few ways to directly determine the shape of large molecules.
Clardy says, the biggest bottleneck in X-ray crystallography.""Some crystallize easily, some crystallize hardly and some are impossible to crystallize,
"Our next grand challenge is to apply this method to protein crystallography, he says
#Synthetic vaccine could prevent future outbreaks of foot-and-mouth disease Virologists have devised a way to create an entirely synthetic vaccine for foot-and-mouth disease.
2."Before this there was no crystal structure for any serotonin receptor. A lot of what was theoretical is known now with a great degree of certainty,
Roth and his colleagues uncovered the receptor structures using X-ray crystallography in which X-ray beams are fired at crystals of the compound,
and the structure is deduced from how the beams scatter. The teams focused on two receptors, called 1b and 2b.
A handful work at room temperature (by using carbon nanotubes to detect electrons for example2), but they cannot operate in water#a serious obstacle to using such devices in living organisms.
but is used in everything from stainless steel to rechargeable batteries. Rare-earth elements are concentrated much less at around 0. 1,
so a polymer that is both flexible and biocompatible is perfect for neural implantation. Multiple functionalities:
they have discovered a method that enlarges tissue samples by embedding them in a polymer that swells
Their idea was to make specimens easier to image at high resolution by embedding them in an expandable polymer gel made of polyacrylate,
and are limited in their ability to image large samples by optical scattering and other aberrations. he exciting part is that this approach can acquire data at the same high speed per pixel as conventional microscopy,
The tiny robot is made of pre-cut polystyrene or paper panels which when heated, fold themselves into a very specific and asymmetrical shape.
The mesh is made of a polymer material with electronics embedded inside. After an injection several centimeters into the brain of a laboratory mouse
researchers made extremely small perforations in a structure made of two thin films of silver separated by a film of silica.
where mixed color pigments are used, there is no color ink used in our structural printing process only different hole sizes on a thing metallic layer, Dr. Jie Gao,
Artists Discover 3-D Printingthe Missouri S&t team believes the mechanical coloring on the silver/silica materials provide a much higher printing resolution than conventional color printing, according to Gizmag.
The technique incorporates some nickel atoms into the diamond crystal structure, forming what is called an 3 defect center.
a rare-earth metal that is highly magnetic and sometimes given to patients to increase contrast in an MRI.
coaxing a cell to envelop a tiny plastic sphere that acts like a resonant cavityhown in green in the micrograph abovehus placing a whole laser within a cell.
In conventional, oxygen-conducting SOFCS, the membrane is made from a ceramic called yttria-stabilized zirconia,
In recent years, researchers have begun exploring alternative membranes made from ceramics called yttrium-doped barium zirconates (BZY.
Mixing the different ceramic components typically requires heating them to temperatures as high as 1700°C But at that extreme temperature,
which makes it harder to mix it uniformly throughout the ceramic. Oayre and his colleagues have helped recently pioneer an alternative mixing scheme called solid state reactive sintering,
Next Mars rovers get a speed boost IT'S time for Martian rovers to put the pedal to the metal.
Next Mars rovers get a speed boost IT'S time for Martian rovers to put the pedal to the metal.
but are rich in carbon rather than silica and may contain large layers of diamond. His team reported on models of such a world dubbed 55 Cancri e in October 2012.
Analysing its microscopic crystals Birger Schmitz at Lund University and his colleagues found that the rock dates to the same time period
Then there are rare-earth metals that could be retrieved from discarded electronics along with bits of tin copper and gold.
Cockell's team found that the altered crystal structure of the rocks absorbed and reflected UV rays.
Snowflakes shorelines and most recently black holes (see Turbulent black holes grow fractal skins as they feed) also exhibit such fractal behaviour.
and steel wires that hangs from an uncrewed spacecraft. The net is fitted with sensors that look for light reflecting from small pieces of debris
Then they shot the ice with a steel pellet travelling at about 7 kilometres a second to simulate the comet smacking into a planet
Quantum dots are light-emitting semiconductor nanocrystals that can be tuned by changing their size, nanometer by nanometer to emit all colors across the visible spectrum.
filled with quantum dots tuned to red and green, that implemented during the synthesis process. Manufacturers use a blue LED in the backlight,
on implementing quantum dots into electronic devices. In a study funded by MIT Deshpande Center for Technological Innovation, Coe-Sullivan, QD Vision cofounder Jonathan Steckel Phd 6,
To do so, they sandwiched a layer of quantum dots, a few nanometers thick, between two organic thin films.
and Asus has a quantum dot notebook. nd there nothing in between that quantum dots can address,
so they can be assembled from building blocks made of polymer chains carrying either an organic MRI contrast agent called a nitroxide
or a fluorescent molecule called Cy5. 5. When mixed together in a desired ratio these building blocks join to form a specific nanosized structure the authors call a branched bottlebrush polymer.
Furthermore the authors of the Nature Communications paper show that incorporation of Rajca s nitroxide in Johnson s branched bottlebrush polymer architectures leads to even greater improvements in the nitroxide lifetime.
In that process, steel sheets are fed into one side of a machine, where theye continuously rolled into a spiral,
and Dan Ainge 2 Keystone system allows the steel rolls to be tapered and made of varying thickness,
and uses steel to make the whole tower, instead of concrete. his makes it much more cost-effective to build much taller towers,
Theye built using very thick steel walls at the base (requiring more than 100 tons of excess steel),
or pieced together with many steel elements using thousands of bolts. f you were to design a 500-foot tower to get strong winds,
industrial-sized machine and the trapezoid-shaped sheets of steel needed to feed into the system.
and feed aluminum coils into one end of a specialized machine that shapes the metal into a seamless gutter. t a better alternative to buying individual sections
Piggybacking on the fundraising bracelet trend of a few years ago, he sold silicone bracelets, raising $60, 000 to fund research on his brother disease.
For the new brain study the researchers delivered chemotherapy drugs via implantable microcapsules made of a biocompatible material called liquid crystal polymer.
Now a team of researchers at MIT led by Alfredo Alexander-Katz the Walter Henry Gale Associate professor of Materials science and engineering has demonstrated a new target-finding mechanism.
a pretzel-shaped silicone tube that could be inserted into the bladder, slowly releasing lidocaine over two weeks.
the researchers developed a prototype device by using a laser to cut a hole in a silicone tube to add drugs. ight
Heejin then redesigned the device as a pretzel-shaped structure by incorporating a superelastic wire made from a special nitinol alloy.
A silica coating on the particles allows additional molecules to attach causing the particles to bind with specific structures within the cell.
Silica makes it completely flexible; it s a well developed material that can bind to almost anything Bawendi says.
Christopher Murray a professor of chemistry and materials science and engineering at the University of Pennsylvania who was connected not with this research says This work exemplifies the power of using nanocrystals as building blocks for multiscale and multifunctional structures.
and his students fabricated filaments from silicone-based rubber, and rigged a spool to automatically reel out the wire onto a conveyor belt.
Surface tension wicks the fluid up the side of the emitters to the tip of the cone whose narrowness concentrates the electrostatic field.
But in the new work they instead used carbon nanotubes atom-thick sheets of carbon rolled into cylinders grown on the slopes of the emitters like trees on a mountainside.
Earlier lab demonstrations of similar systems could only produce devices a few centimeters on a side with expensive metal substrates so were not suitable for scaling up to commercial production he says.
While the team has demonstrated working devices using a formulation that includes a relatively expensive metal ruthenium we re very flexible about materials Chou says.
In theory you could use any metal that can survive these high temperatures. This work shows the potential of both photonic engineering
and materials science to advance solar energy harvesting says Paul Braun a professor of materials science and engineering at the University of Illinois at Urbana-Champaign who was involved not in this research.
The group is now working to optimize the system with alternative metals. Chou expects the system could be developed into a commercially viable product within five years.
The coils are made from a shape-memory alloy (SMA) a type of material that remembers an engineered shape
That s where shape-memory alloys may provide a solution. Such materials only contract when heated and can easily be stretched back to a looser shape when cool.
To find an active material that would be most suitable for use in space Holschuh considered 14 types of shape-changing materials ranging from dielectric elastomers to shape-memory polymers before settling on nickel-titanium shape
-memory alloys. When trained as tightly packed small-diameter springs this material contracts when heated to produce a significant amount of force given its slight mass ideal for use in a lightweight compression garment.
Shape-memory alloys like nickel-titanium can essentially be trained to return to an original shape in response to a certain temperature.
and holds a joint appointment with the Department of Civil and Environmental engineering, says the new material is essentially a layer of electro-active elastomer that could be adapted quite easily to standard manufacturing processes
Learning from nature Cephalopods achieve their remarkable color changes using muscles that can alter the shapes of tiny pigment sacs within the skin for example
The new synthetic material is a form of elastomer, a flexible, stretchable polymer. t changes its fluorescence and texture together,
in response to a change in voltage applied to it essentially, changing at the flip of a switch, says Qiming Wang,
that applying voltage can dynamically change surface textures of elastomers, Zhao says. he texturing and deformation of the elastomer further activates special mechanically responsive molecules embedded in the elastomer,
which causes it to fluoresce or change color in response to voltage changes, Craig adds. nce you release the voltage,
both the elastomer and the molecules return to their relaxed state like the cephalopod skin with muscles relaxed.
Using a system like this new elastomer, Zhao suggests, either on uniforms or on vehicles, could allow the camouflage patterns to constantly change in response to the surroundings. he U s. military spends millions developing different kinds of camouflage patterns,
Those crystals interfere with the normal magnetic spins of hydrogen atoms. When exposed to a powerful magnetic field hydrogen atoms align their spins in the same direction.
Tracking infectionhemozoin crystals are produced in all four stages of malaria infection including the earliest stages
says Ming Dao, a principal research scientist in MIT Department of Materials science and engineering and one of the senior authors of the paper,
the lead can simply be recycled into new solar panels. he process to encapsulate them will be the same as for polymer cells today,
Yang Yang, a professor of materials science and engineering at the University of California at Los angeles who was involved not in this research,
The nanoparticles are made of a small polymer lipid conjugate; unlike liver-targeting nanoparticles these preferentially target the lung
and materials science at the University of Southern California who was not part of the research team.
the outer layers are composed of a shape-memory polymer that folds when heated. After the laser-cut materials are layered together a microprocessor
The researchers fabricated an array of the microhairs onto an elastic transparent layer of silicone.
Others have designed such magnetically actuated materials by infusing polymers with magnetic particles. However Wang says it s difficult to control the distribution and therefore the movement of particles through a polymer.
MIT engineers show their magnetic microhairs in action. Video: Melanie Gonick/MIT Instead she and Zhu chose to manufacture an array of microscopic pillars that uniformly tilt in response to a magnetic field.
and bonded the nickel pillars to a soft transparent layer of silicone. The researchers exposed the material to an external magnetic field placing it between two large magnets
Through a combination of surface tension and tilting pillars water climbed up the array following the direction of the pillars.
Since the material s underlying silicone layer is transparent the group also explored the array s effect on light.
He adds This work cleverly combines low-hysteresis droplet movement with low-magnetic-field-driven droplet propulsion to achieve impressive capabilities.
But if the graphene starts out with high electron concentration the pulse decreases its conductivity the same way that a metal usually behaves.
Our experiment reveals that the cause of photoconductivity in graphene is very different from that in a normal metal or semiconductors,
and Yong Cheol Shin a graduate student in materials science and engineering. The work received support from the U s. Department of energy and the National Science Foundation n
and weld even through a half-inch of steel at greater efficiencies than today s industrial lasers.
and fiber that first transfer energy from diode lasers into a medium usually a crystal before converting it into a laser beam.
Although his initial tests involved copper plates he says any conductive metal would do including cheaper aluminum.
and Wang s 2013 finding in attempting to develop an improved heat-transfer surface to be used as a condenser in applications such as power plants that droplets on a superhydrophobic surface convert surface energy to kinetic energy as they merge to form larger droplets.
A polymer solution is poured onto a glass plate Hyder explains; this casting plate is immersed then in a nonsolvent bath to induce precipitation to form a film.
The technique creates a bilayered polymer phase: One layer is polymer-rich and one is not.
As they precipitate out the polymer-rich phase develops the smaller pores; the polymer-lean phase makes the larger ones.
Since the solutions form a single sheet of film there is no need for bonding layers together
which can result in a weaker filter. There is no separate layer it s completely integrated
As a final stage a different polymer is added to give the material including the lining of the pores surfaces that attract
Anish Tuteja an assistant professor of materials science and engineering at the University of Michigan who was involved not in this research calls it a very interesting and innovative approach to fabricating membranes that can separate out nanoemulsions.
The material forms tiny crystals a chemically ordered state but with intrinsic randomness such that the orientations of the stacked molecules can be arbitrary
and the sizes of the crystals different, forming aggregate structures that are disordered highly. That combination of order and disorder contributes to eumelanin broadband absorption, the team found. t a naturally existing nanocomposite,
These insights may be useful in developing materials for applications such as pigments, he says, or in improving the efficiency of solar cells.
and cut off some metal in the back that was dead weight and built a composite nacelle to hold our custom electronics
or more concentric spheres made of short chains of a chemically modified polymer. RNA is packaged within each sphere
The particles are coated with a polymer called PEG, which protects them from being broken down in the body
The injectable device is made of two types of silicone one that provides the MRI signal and one that offers structural support.
Injecting magnetic materials known as contrast agents can help boost the visibility of certain tissues but these agents are designed typically to break down soon after the MRI is performed.
The new MRI sensor combines two forms of silicone a solid called PDMS and a substance known as DDMPS which has an oily consistency.
what s called a swollen polymer. The researchers shaped this polymer into a 1. 5-millimeter sensor that could be implanted in tissue during a biopsy;
they also created smaller particles (tens of microns long) that can be injected through a needle.
which alters the proton spins inside the silicone a phenomenon that can be detected with MRI.
This is the first direct observation of exciton diffusion processes Bulovic says showing that crystal structure can dramatically affect the diffusion process.
While these experiments were carried out using a material called tetracene a well-studied archetype of a molecular crystal the researchers say that the method should be applicable to almost any crystalline or thin-film material.
storable and distributable, says Jeffrey Grossman, an associate professor of materials science and engineering, who is a co-author of a paper describing the new process in the journal Nature Chemistry.
Grossman team tried attaching the molecules to carbon nanotubes (CNTS), but t incredibly hard to get these molecules packed onto a CNT in that kind of close packing,
The adoption of carbon nanotubes to increase materialsenergy storage density is lever, says Yosuke Kanai, an assistant professor of chemistry at the University of North carolina who was involved not in this work.
and better photochromic compounds and composite materials that optimize the storage of solar energy in chemical bonds, Kanai says.
These crystals are doped with elements such as ytterbium, gadolinium, erbium, and thulium, which emit visible colors
the researchers can tune the crystals to emit any color in the visible spectrum. To manufacture the particles, the researchers used stop-flow lithography,
This approach allows shapes to be imprinted onto parallel flowing streams of liquid monomers chemical building blocks that can form longer chains called polymers.
In this case, each polymer stream contains nanocrystals that emit different colors, allowing the researchers to form striped particles.
The researchers demonstrated the versatility of their approach by using two polymers with radically different material properties one hydrophobic and one hydrophilic o make their particles.
and other substances including living cells MIT engineers have coaxed bacterial cells to produce biofilms that can incorporate nonliving materials such as gold nanoparticles and quantum dots.
and films studded with quantum dots or tiny crystals that exhibit quantum mechanical properties. They also engineered the cells
To add quantum dots to the curli fibers the researchers engineered cells that produce curli fibers
along with a different peptide tag called Spytag which binds to quantum dots that are coated with Spycatcher a protein that is Spytag s partner.
along with the bacteria that produce histidine-tagged fibers resulting in a material that contains both quantum dots and gold nanoparticles.
In a new Nature Materials paper, the researchers report boosting plantsability to capture light energy by 30 percent by embedding carbon nanotubes in the chloroplast,
During the first stage, pigments such as chlorophyll absorb light, which excites electrons that flow through the thylakoid membranes of the chloroplast.
the researchers also embedded semiconducting carbon nanotubes, coated in negatively charged DNA, into the chloroplasts. Plants typically make use of only about 10 percent of the sunlight available to them,
but carbon nanotubes could act as artificial antennae that allow chloroplasts to capture wavelengths of light not in their normal range, such as ultraviolet, green,
With carbon nanotubes appearing to act as a rosthetic photoabsorber photosynthetic activity measured by the rate of electron flow through the thylakoid membranes was 49 percent greater than that in isolated chloroplasts without embedded nanotubes.
When nanoceria and carbon nanotubes were delivered together, the chloroplasts remained active for a few extra hours. The researchers then turned to living plants
Lean green machines The researchers also showed that they could turn Arabidopsis thaliana plants into chemical sensors by delivering carbon nanotubes that detect the gas nitric oxide,
When the target molecule binds to a polymer wrapped around the nanotube, it alters the tube fluorescence. e could someday use these carbon nanotubes to make sensors that detect in real time, at the single-particle level,
free radicals or signaling molecules that are at very low-concentration and difficult to detect, Giraldo says. his is a marvelous demonstration of how nanotechnology can be coupled with synthetic biology to modify
and the polymer ring that protects the electronics in the fish s guts. The long haulthe fish can perform 20
the better, says Darrell Irvine, a professor of biological engineering and of materials science and engineering, and the senior author of the paper.
For example, Atlas recently made the switch to more advanced ropes that have higher tensile strength, with smaller diameters. o carry a 200-foot section of rope was up to 15 pounds;
To create these ynthetic antibodies, the researchers used carbon nanotubes hollow, nanometer-thick cylinders made of carbon that naturally fluoresce
The MIT team found that they could create novel sensors by coating the nanotubes with specifically designed amphiphilic polymers polymers that are drawn to both oil and water, like soap.
or diabetes in living systems. his new technique gives us an unprecedented ability to recognize any target molecule by screening nanotube-polymer complexes to create synthetic analogs to antibody function,
Synthetic antibodies The new polymer-based sensors offer a synthetic design approach to the production of molecular recognition sites enabling, among other applications, the detection of a potentially infinite library of targets.
Moreover, this approach can provide a more durable alternative to coating sensors such as carbon nanotubes with actual antibodies,
Their approach takes advantage of a phenomenon that occurs when certain types of polymers bind to a carbon nanotube.
These polymers, known as amphiphilic, have both hydrophobic and hydrophilic regions. These polymers are designed and synthesized such that
when the polymers are exposed to carbon nanotubes, the hydrophobic regions latch onto the tubes like anchors
and the hydrophilic regions form a series of loops extending away from the tubes. These loops form a new layer surrounding the nanotube, known as a corona.
and the polymer before it attaches to the nanotube. he idea is that a chemist could not look at the polymer
because the polymer itself can selectively recognize these molecules. It has to adsorb onto the nanotube and then,
by having certain sections of the polymer exposed, it forms a binding site, Strano says.
The researchers used an automated, robot-assisted trial and error procedure to test about 30 polymer-coated nanotubes against three dozen possible targets, yielding three hits.
They are now working on a way to predict such polymer-nanotube interactions based on the structure of the corona layers,
and their targets. hat happening to the polymer and the corona phase has been a bit of a mystery,
then pulling back inward due to surface tension and bouncing away depends on the time period of oscillations in a vibrating drop, also known as the Rayleigh time.
as well as for processes such as spray cooling of hot metal. One application now being considered by Varanasi
In 2006, Doyle lab developed a way to create huge batches of identical particles made of hydrogel, a spongy polymer.
From metals to drugsthe researchers now hope to explore mitochondrial-targeted cisplatin s potential use as a chemotherapy drug by testing it in animals.
They also plan to try targeting cisplatin and other metal-based drugs to different parts of cells
Cisplatin and a handful of other platinum drugs are the only metal-based drugs now approved for human use
but researchers around the world are working on other types of metal-based drugs. People are interested really in using metals as therapeutics
but they re difficult to control and elucidating the cellular targets of metal-based drugs is challenging
because they can interact with so many different biomolecules Radford says. By targeting specific cellular organelles with the same therapeutic molecules we can learn a lot about how the cells respond to a given compound
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