and radiation spectrum engineering by strong optical interference effect. The graphene vibrates during light emission due to the flexural mode of graphene at high temperature.
"At the highest temperatures, the electron temperature is much higher than that of acoustic vibrational modes of the graphene lattice,
-and at its ultimate size limit-one atom thick.""The team is currently analysing and characterising the performance of the devices, including the time taken to turn on
#Chemists Witness Atoms of One Chemical element Morph Into Another The research appears in Nature Materials, June 15, 2015, online in advance of print.
a professor of chemistry at Tufts and senior author on the paper, worked with iodine-125 radioactive isotope that is routinely used in cancer therapies.
which can produce images of each atom in a material surface, they observed individual atoms of iodine-125 decay.
As each atom decayed it lost a proton and became tellurium-125, a nonradioactive isotope of the element tellurium.
The transformation of one element to another occurred when the researchers infused a single droplet of water with iodine-125
and deposited it on a thin layer of gold. When the water evaporated, the iodine atoms bonded with the gold.
The researchers inserted the tiny samplemaller than a dimento the microscope. Iodine-125 atoms have a half-life of 59 days,
meaning that at any time, any atom of the radioisotope will decay, giving off vast amounts of energy and becoming the isotope of tellurium,
with half of the atoms decaying every 59 days. It was impossible to predict when any one of the trillions of atoms in the sample would transmute into tellurium,
so the researchers worked up to 18 hours a day for several weeks so they wouldn miss the transformations.
Eventually they managed to take scanning tunneling microscope images that showed small atom-sized spots all over the surface.
An international collaboration with Angelos Michaelides, Ph d.,a professor of theoretical chemistry at UCL, and Philipp Pedevilla, a doctoral candidate at UCL, helped interpret these images
and assign the features as newly formed tellurium atoms. To verify that they had seen indeed the transformation,
they studied one of the samples over several months with an X-ray photoelectron spectrometer to determine its exact chemical makeup. y taking the measurement every week or two,
we could see the chemical transmutation from one element to another, as the sample went from mostly iodine to mostly tellurium,
Then Alex Pronschinske, Ph d.,first author on the paper and a postdoctoral researcher in Sykeslab, suggested that they measure the electrons emitted by the sample without prodding from X-rays in the photoelectron spectrometer.
He was interested particularly in the emission of low energy electrons, which have been shown to be very effective in radiation oncology
because they break cancer cellsdna into pieces. Because these electrons can travel only 1 to 2 nanometers human hair is about 60,000 nanometers widehey do not affect healthy tissue and organs nearby.
The team calculated the number of low energy electrons they expected would be emitted by the sample
based partly on data from simulations used by the medical community. They found that the gold-bonded iodine-125 emitted six times as many low energy electrons as plain iodine-125.
The gold, says Sykes, as acting like a reflector and an amplifier. Every surface scientist knows that
if you shine any kind of radiation on a metal, you get this big flux of low energy electrons coming out. he finding suggests a new avenue for radiation oncology:
make nanoparticles of gold, bond iodine-125 to them, then affix the nanoparticles to antibodies targeting malignant tumors
and emit low energy electrons, destroying the tumor DNA. The gold-based nanoparticles would be flushed out of the body,
which doctors treat some cancers by putting radioisotopes, including iodine-125, into tiny titanium capsules and implanting them in tumors.
Instead of emitting large amounts of low energy electrons as the gold-bound iodine does, the titanium capsules inhibit radiation,
Sykes says, making such therapies less effective than they could be. He has applied for a patent on the new technique.
Researchers in Sykes'lab are now assessing precisely how the low energy electrons travel through biological fluids.
"Enhancement of low energy electron emission in 2-D radioactive films.""Nature Materials. http://dx. doi. org/10.1038/nmat4323.
Artificial chiral nanocrystals can be produced by fastening special chiral ligand molecules to the nanocrystal surface.
In the natural world, chirality is an inherent property of many objects that range from spiral galaxies to elementary particles.
and its molecules possess two optical mirror isomers. One of these isomers is beneficial and relieves the pain,
L-cysteine is a chiral molecule and it is used widely for phase transfers as a ligand.
"which are single stranded-dna DNA or RNA molecules that bind to the receptors on the target organism's cell outer membrane,
builds on recent research by the same team that previously identified a fat-and-sugar molecule called GSL as the chief culprit behind a range of biological glitches that affect the body's ability to properly use, transport
The newly published report reveals the scientists appear to have cleared that hurdle by encapsulating D-PDMP into tiny molecules,
and track the nanoparticles'movement inside the animals'bodies by tagging them with a radioactive tracer that lit up on a CT SCAN.
Mice treated with placebo showed high levels of GSL--the molecule responsible for altered cholesterol metabolism
the researchers were able to visualise how ions move around in a supercapacitor. They found that
electrolyte ions are stored in the anode. As the battery discharges, electrolyte ions leave the anode
and move across the battery to chemically react with the cathode. The electrons necessary for this reaction travel through the external circuit,
generating an electric current. A supercapacitor is similar to a battery in that it can generate and store electric current,
instead, positive and negative electrolyte ions simply tickto the surfaces of the electrodes when the supercapacitor is being charged.
the ions can easily opoff the surface and move back into the electrolyte. The reason why supercapacitors charge
and discharge so much faster is that the tickingand oppingprocesses happen much faster than the chemical reactions at work in a battery. o increase the area for ions to stick to,
like a carbon sponge, said Griffin. ut it hard to know what the ions are doing inside the holes within the electrode we don know exactly what happens
and the positive ions are attracted to the surface as the supercapacitor charges. But in the positive electrode, an ion xchangehappens,
as negative ions are attracted to the surface, while at the same time, positive ions are repelled away from the surface.
Additionally, the EQCM was used to detect tiny changes in the weight of the electrode as ions enter and leave.
This enabled the researchers to show that solvent molecules also accompany the ions into the electrode as it charges. e can now accurately count the number of ions involved in the charge storage process
and see in detail exactly how the energy is stored, said Griffin. n the future we can look at how changing the size of the holes in the electrode
and the ion properties changes the charging mechanism. This way we can tailor the properties of both components to maximise the amount of energy that is stored.
The next step, said Professor Clare P. Grey, the senior author on the paper, s to use this new approach to understand why different ions behave differently on charging, an ultimately design systems with much higher capacitances.
Funding for the project was provided by the UK Engineering and Physical sciences Research Council and the European Research Council
which works with last generation liposomes particles, concentrated in droplets, which function as a conveyor that wraps proteins
Professor of Chemistry at the University of Toronto. am pleased to partner with Bruker to expand the great potential of ssnom as a versatile tool for broader scientific discovery. nspire is a nanoscale characterization system that extends atomic force microscopy into the chemical
the team has unveiled how fluids behave under extreme confinement by using micron-sized particles known as colloids to act as oversized atoms.
Atoms are tiny and cannot be seen under a microscope. This is not the same for colloidal particles,
however, and this makes it possible for scientists to understand the behaviour of fluids such as water at extremely small scales.
#Electron Cryo-Microscopy Offers Extraordinary Details of Proteasome Complex Scientists have pioneered the use of a high-powered imaging technique to picture in exquisite detail one of the central proteins
Researchers used a technique called electron cryo-microscopy, or'CRYO EM'-imaging samples frozen to-180oc-to show the proteasome complex in such extraordinary detail that they could view a prototype drug bound to its active sites.
The results could help improve scientists'ability to build molecules that interlock very specifically with target sites on proteins-a fundamental part of designing new anticancer drugs.
The research could help other scientists to use CRYO EM in structure-based drug design studies-in which researchers build the best possible drugs starting from a molecule which already binds to the active site of a target protein.
An inhibitor molecule used by the researchers was shown to be visibly bound at each of its three target sites on the proteasome.
Electron cryo-microscopy is emerging as a complementary approach in cancer drug design to X-ray crystallography
-which involves generating highly ordered crystals of proteins and hitting them with X-ray radiation. CRYO EM offers the opportunity to study protein complexes in conditions closer to those in the human body.
They bombarded their samples with electrons and generated images using complex image-processing software. Senior study author Dr Edward Morris, Team Leader in Structural Electron microscopy at The Institute of Cancer Research, London, said:"
"Revealing the molecule's detailed shape could be the first step towards designing more precise drugs to block it.
This molecule plays an important role in some cancers and drugs that block it are already available to patients
Michael Urbakh of the TAU School of Chemistry, both of the TAU-Tsinghua XIN Center, in collaboration with Prof.
such vibrations produce a 300%improvement in the rate of water diffusion by using computers to simulate the flow of water molecules flowing through nanotubes.
Urbakh's group at TAU. Ming catalyzed the international collaboration.""The students from Tsinghua are remarkable.
The most famous example of this is Cherenkov radiation, wakes produced as electrical charges travel through liquids faster than the phase velocity of light, emitting a glowing blue wake.
and Cherenkov radiation,"said Patrice Genevet, a lead author, formerly of SEAS, currently affiliated with the Singapore Institute of Manufacturing Technology y
#Smart Sensor Chip with Nanocavities for Early Prostate Cancer Diagnosis Researchers at the University of Birmingham believe that the novel technology will help improve the process of early stage diagnosis. Glycoprotein molecules,
targeted glycoprotein molecules that are differentiated by their modified carbohydrate chains. In doing so, they developed a more accurate and efficient way of diagnosing prostate cancer than the current tests
"Most previous research on detecting glycoproteins centered on the protein of the molecule. Problematically for diagnosis, the protein part of glycoproteins does not always change
The findings, published in the journal Chemical science, show how the rate of false readings that come with antibody based diagnosis can be reduced by the smart technology that focuses on the carbohydrate part of the molecule.
which has specific sugars in a specific location in the molecule. Professor Mendes added""Biomarkers such as glycoproteins are essential in diagnostics as they do not rely on symptoms perceived by the patient,
the sugar part of the prostate cancer glycoprotein is reacted with a custom-designed molecule that contains a boron group at one end (the boron linkage forms a reversible bond to the sugar).
The other end of this custom molecule is made to react with molecules that have been tethered to a gold surface.
before the rest of the surface is blocked with a third molecule. When the glycoprotein is removed (by breaking the reversible boron bonds) it leaves behind a perfect cast.
Within that cast, there was a special area with boron-containing molecules that can recognise a specific set of sugars.
and that is our world we can control cellulose-based materials one atom at a time. The Hinestroza group has turned cotton fibers into electronic components such as transistors and thermistors
Two of Hinestroza students created a hooded bodysuit embedded with insecticides using metal organic framework molecules,
can be manipulated at the nano level to build nanoscale cages that are the exact same size as the gas they are trying to capture. e wanted to harness the power of these molecules to absorb gases
The pulse generates an electric field as well as injecting electrons into the sample. By using a new theoretical approach developed by Dr. Kajita,
San diego graduate student has found a way to use mass-produced graphene, an allotrope of carbon that is one atom-thick.
and it 200 times stronger than steel because of the way the atoms bond to form a hexagonal pattern (think of chicken wire) with a cloud of free electrons hovering above and below it,
#Silver-Ion Infused Lignin Nanoparticles Effectively Kill Bacteria Orlin Velev, an engineer at NC State engineer,
along with other researchers developed nanoscale particles that introduce silver antimicrobial potency to a biocompatible lignin core.
The silver-ion infused lignin nanoparticles, coated with a layer of charged polymer that aids the particles to stick to the target microbes,
can effectively destroy a wide range of harmful microorganisms, including E coli bacteria. When the targeted bacteria are wiped out by nanoparticles,
silver gets depleted from these particles. Upon disposal, the rest of the particles also degrade easily due to their biocompatible lignin core.
This greatly restricts the harm posed to the environment. People have been interested in using silver nanoparticles for antimicrobial purposes,
The nanoparticles infused with silver ions were utilized to attack Pseudomonas aeruginosa, disease-causing bacteria; E coli, a bacterial species that cause food poisoning;
We are now working to scale up the process to synthesize the particles under continuous flow conditions.
#New Method to Visualize Topological Insulators at the Nanoscale Using Large particle accelerator Scientists trying to improve the semiconductors that power our electronic devices have focused on a technology called spintronics as one especially promising area of research.
a new generation of machines that use quantum mechanics to solve complex problems with extraordinary speed.
The technique involves aiming a highly focused stream of ions at the topological insulator. To generate that beam of ions,
the researchers used a large particle accelerator called a cyclotron, which accelerates protons through a spiral path inside the machine
and forces them to collide with a target made of the chemical element tantalum. This collision produces lithium-8 atoms
which are ionized and slowed down to a desired energy level before they are implanted in the topological insulators.
In betaetected nuclear magnetic resonance, ions (in this case, the ionized lithium-8 atoms) of various energies are implanted in the material of interest (the topological insulator) to generate signals from the material layers of interest.
Bouchard said the method is suited particularly well for probing regions near the surfaces and interfaces of different materials.
The researchers used the large TRIUMF cyclotron in Vancouver, British columbia. Co-authors of the PNAS research were Danny King, formerly a UCLA graduate student in chemistry and biochemistry;
emitting specific wavelengths of light that differ depending on the molecules that are present. This fluorescence is imaged then back onto the camera.
we can determine how much of each fluorescing molecule is in the sample, said Orth. hat makes our microscope particularly powerful is that it records many different colors at once,
the researchers applied various dyes that adhere to specific molecules within a cell sample. These dyes respond to laser light by fluorescing at specific frequencies
which enables the analysis of the 3d structures of these particles for the first time. Metallic nanoparticles have dimensions in the nanometer range
which is a one-molecule-thick bag capable of holding liquid within it during exposure to the ultra high vacuum of the electron microscope column.
A direct electron detector is the second component which has a much higher sensitivity than conventional camera film.
This in depth information allowed the research team to gain new insights into the growth of these highly useful particles at individual atom level.
Particle 1 in action Monash University Youtube. comthe field had expected cubical or at least highly symmetrical platinum nanocrystals. t was surprising to learn that they form asymmetrical multi-domain structures,
#Simpler Thermodynamic Approach Could Help Improve the Performance of Graphene-Based Nanoelectronic Devices The researchers found that the energy of ultrafast electrical currents passing through graphene is converted very efficiently into electron heat,
making graphene electrons behave just like a hot gas. he heat is distributed evenly over all electrons.
maybe they could use our particles as well, Brandl says. hen we came up with the idea to use our particles to remove toxic chemicals, pollutants,
or hormones from water, because we saw that the particles aggregate once you irradiate them with UV LIGHT. trap for ater-fearingpollutionthe researchers synthesized polymers from polyethylene glycol,
a widely used compound found in laxatives, toothpaste, and eye drops and approved by the Food and Drug Administration as a food additive,
in a solution hydrophobic pollutant molecules move toward the hydrophobic nanoparticles, and adsorb onto their surface,
the stabilizing outer shell of the particles is shed, and now nrichedby the pollutants they form larger aggregates that can then be removed through filtration, sedimentation,
according to the researchers, was confirming that small molecules do indeed adsorb passively onto the surface of nanoparticles. o the best of our knowledge,
it is the first time that the interactions of small molecules with preformed nanoparticles can be measured directly,
and molecules. he interactions we exploit to remove the pollutants are nonspecific, Brandl says. e can remove hormones, BPA,
we showed in a system that the adsorption of small molecules on the surface of the nanoparticles can be used for extraction of any kind,
Toxic heavy metal ions like mercury, lead and arsenic are released into the water through human activity, including manufacturing and industrial processes.
UW-Madison chemical engineering Professor Manos Mavrikakis and his collaborators have turned to the nanoscale structure of particles,
arranging atoms to achieve more potent chemical reactions while using less material. In a paper to be published July 24 in the journal Science
the researchers describe how they teased a small number of platinum atoms into hollow"cage"structures that prove to be 5. 5 times as potent as conventional platinum non-hollowed particles in an oxygen-reduction reaction crucial
then deposit a few layers of platinum atoms on top of it. Calculations by Mavrikakis'group show that platinum atoms have a tendency to burrow into the palladium during the deposition.
This allows the palladium to be removed by etching agents, leaving behind a cagelike structure in the initial shape of the palladium template with faces formed by layers of platinum just three to five atoms thick.
Reactants can flow into the hollow structure through holes in the faces interacting with more platinum atoms in the chemical reaction than would be the case on a flat sheet of platinum or traditional, nonhollowed nanoparticles."
"Because of this new structure they're taking on, they're naturally shortening the distances between platinum atoms,
which makes the platinum more active for the oxygen reduction reaction, "says Luke Roling, a graduate student in Mavrikakis'lab."We're also able to use more of the platinum atoms than we were before--at best,
you could get up to twice as much of your platinum exposed.""Mavrikakis points out that, in a scaled-up version of this process,
it would be possible to reuse palladium atoms after etching agents remove them from the nanoparticle.
and structure of the particle--details that make a tremendous difference in how reactive the particle ultimately is."
or more layers--it's harder to remove the palladium atoms and obtain the desired hollowed cages.
and between three and six atom-thin platinum layers. When these nanocage structures are used in fuel cell electrodes,
who is also a Georgia Research Alliance eminent scholar. e can also control the arrangement of atoms on the surface
it is possible for the new structures to use a maximum of two-thirds of the platinum atoms in an ultra-thin three-layer shell.
These particles showed a tendency to clump together via the sintering process, thereby minimizing the surface area. y using hollow structures,
we can use much larger particle sizes about 20 nanometers and we really don lose any surface area
Xia commented. e expect the durability of these larger particles to be much better. Other applications, including catalytic converters in automobiles, employ significant quantities of platinum.
and electrons that propagate along a surface of a metal strip. At the end of the strip they are converted back to light once again.
The smart Empa membrane contains special dye molecules known as spiropyrans. If UV LIGHT is beamed onto these spiropyran molecules they alter their chemical structure
and become charged (polar). When irradiated with visible light they revert to their original neutral structure.
and glucose molecules diffuse relatively easily through the membrane from the skin. If irradiated with visible light considerably fewer glucose molecules pass through the membrane.
The measurement involves sticking the measuring head which is around three centimeters in size to the baby's skin
some glucose molecules diffuse through the membrane from the skin. On the other side of the membrane the glucose is mixed with a fluid
which results in an Internet of Awareness#through the convergence of Iot-connected lighting and sensor fusion#said Sajol Ghoshal who is responsible for Emerging Sensor Strategies at ams.#
We've been looking for a long time for a molecule like this. It has all the properties consistent with a sensor.
This DOE component is structured a micro optical element designed to modulate the photon propagation within the skin tissue
But some devices are starting to use fast silicon-germanium radio chips operating at millimeter (mm) wavelengths above 10 GHZ.
he said. eing able to detect trace components, single molecules, autonomously and reliably, without the need for sample return or hardware consumables in a really tiny,
Jiching Yu, PNAS first author and a Phd student in Gu labhyaluronic acid and 2-nitromidazole were connected to create a new double ended molecule, with one side hydrophilic and the other hydrophobic.
When these molecules self-assemble into a vesicle, their hydrophilic ends pointed outward and the hydrophobic ends pointed inward,
Called-Eye the invention senses radiation across the spectrum between microwaves and infrared, known as the Terahertz (THZ) region of the spectrum a goal that has challenged scientists for over 30 years.
even down to the level of very small packets of quantum energy (a single photon.
The electrons in the silicon layer are isolated so from the silicon lattice they become highly sensitive to incoming radiation.
This revolutionary e-cooling process is the secret to Q-Eye sensor exceptional performance, enabling fast imaging and material identification.
all conventional absorbers strongly interact with the radiation of other frequencies, reflecting it back and not letting it pass through.
and the hazards associated with ionising radiation limit the frequency with which X-rays can be performed.
Subsequent pulmonary problems in the mice were linked mainly to coarser-grained smoke particles and cardiac problems to finer-grained particles.
A widely cited 2012 study, published in the journal Environmental Health Perspectives, estimated that about 339,000 deaths worldwide between 1997 and 2006 were associated with forest, grass and peat fires.
because finer-grained particles are thought to penetrate further into the bloodstream than coarser ones do,
Finer-grained particles are also harder to block with the simple surgical masks that many people in Asian cities have worn traditionally as protection against air pollution.
which also includes PM2. 5 particles. No one is sure because so little research has been done to test the theory.
"We should be sending robots into Fukushima instead of asking human volunteers to take lethal doses of radiation.
#Hadron collider discovers new particle Scientists at the Large hadron collider have announced the discovery of a new particle called the pentaquark.
It was predicted first to exist in the 1960s but, much like the Higgs boson particle before it,
was made by the Hadron collider's LHCB experiment. The findings have been submitted to the journal Physical Review Letters.
In 1964, two physicists-Murray Gell Mann and George Zweig-independently proposed the existence of the subatomic particles known as quarks.
They theorised that key properties of the particles known as baryons and mesons were explained best if they were made in turn up of other constituent particles.
Zweig coined the term"aces"for the three new hypothesised building blocks, but it was Gell-Mann's name"quark"that stuck.
This model also allowed for other quark states, such as the pentaquark. This purely theoretical particle was composed of four quarks and an antiquark (the antimatter equivalent of an ordinary quark.
New states During the mid-2000s, several teams claimed to have detected pentaquarks, but their discoveries were undermined subsequently by other experiments."
"There is quite a history with pentaquarks, which is also why we were very careful in putting this paper forward,"Patrick Koppenburg,
physics co-ordinator for LHCB at Cern, told BBC News."It's just the word'pentaquark
'which seems to be cursed somehow because there have been many discoveries that were then superseded by new results that showed that previous ones were actually fluctuations and not real signals."
"Physicists studied the way a subatomic particle called Lambda b decayed -or transformed-into three other particles inside LHCB.
The analysis revealed that intermediate states were involved sometimes in the production of the three particles.
These intermediate states have been named Pc (4450)+ and Pc (4380+."+"We have examined all possibilities for these signals,
Previous experiments had measured only the so-called mass distribution where a statistical peak may appear against the background noise"-the possible signature of a novel particle.
But the collider enabled researchers to look at the data from additional perspectives, namely the four angles defined by the different directions of travel taken by particles within LHCB."
"We are transforming this problem from a one-dimensional to a five dimensional one...we are able to describe everything that happens in the decay,
"said Dr Koppenburg who first saw a signal begin to emerge in 2012.""There is no way that
what we see could be due to something else other than the addition of a new particle that was observed not before."
"The pentaquark is not just any new particleit represents a way to aggregate quarks, namely the fundamental constituents of ordinary protons and neutrons,
the protons and neutrons from which we're all made, is constituted.""The LHC powered up again in April following a two-year shutdown to complete a programme of repairs and upgrades d
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