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The basic concept is to equip drug molecules with chemical components that change shape in response to heat or light.
and deactivating particular enzyme molecules in the body, disabling their function. Antibiotics typically work by disrupting functions that are essential to the survival of bacterial cells.
which consists of two benzene molecules joined together by two nitrogen atoms linked by a double chemical bond.
They must remain either both on the same side of the molecule in a flattened C shape,
molecules with the same molecular formula but different structures and properties. Crucially, heat and light can temporarily loosen up the bond between the nitrogen atoms,
allowing them to rotate. If the Z-shaped isomer absorbs ultraviolet light, it will become switch to the C-shaped isomer.
Feringa and colleagues substituted the azobenzene switch for a similar chemical grouping within several variants of an antibacterial molecule called a quinolone,
Feringa says he is now working on developing molecules than can be shifted shape with visible light, or better still infrared,
localized heating of the molecules leads to a temperature and pressure increase in the gas. f the incident light intensity is modulated,
The predicted results include both the pyrolysis process of individual particles and the tar concentration in the gas as a response to the interaction between hot air and wood particles.
A detailed analysis of results enables engineers to improve reactor design for higher energy efficiency. Such reactors not only improve operating conditions
and radiation despite the drug effectiveness to prevent DCIS recurrence and to lower the risk of future breast cancer. elivering the drug though a gel,
and radiation are given oral tamoxifen for five years to reduce the risk of the DCIS recurring at the same place
Perhaps the biggest roadblock to adopting fusion energy is that the economics haven t penciled out.
Fusion power designs aren t cheap enough to outperform systems that use fossil fuels such as coal and natural gas.
and will present results this week at the International atomic energy agency s Fusion energy Conference in St petersburg Russia. ight now this design has the greatest potential of producing economical fusion power of any current conceptsays Thomas Jarboe a professor
The design builds on existing technology and creates a magnetic field within a closed space to hold plasma in place long enough for fusion to occur allowing the hot plasma to react and burn.
which you generate fusion is the medium in which you re also driving all the current required to confine itsutherland says.
A fusion power plant producing 1 gigawatt (1 billion watts) of power would cost $2. 7 billion
while a coal plant of the same output would cost $2. 8 billion according to their analysis. f we do invest in this type of fusion we could be rewarded
and get significant fusion power output. The team has filed patents on the reactor concept and plans to continue developing
A polymer is a type of large molecule that forms plastics and other familiar materials. he field is rather immature it s in the infancy stagesays Luping Yu a professor in chemistry at the University of Chicago.
and receive electrons to generate electrical current when exposed to light. The new polymer developed by Yu s group called PID2 improves the efficiency of electrical power generation by 15 percent
when added to a standard polymer-fullerene mixture. ullerene a small carbon molecule is one of the standard materials used in polymer solar cellslu says. asically in polymer solar cells we have a polymer as electron donor
and fullerene as electron acceptor to allow charge separation. n their work the researchers added another polymer into the device resulting in solar cells with two polymers and one fullerene.
In order for a current to be generated by the solar cell electrons must be transferred from polymer to fullerene within the device.
But the difference between electron energy levels for the standard polymer-fullerene is large enough that electron transfer between them is difficult.
which improve the mobility of electrons throughout the material. The fibers serve as a pathway to allow electrons to travel to the electrodes on the sides of the solar cell. t s like you re generating a street
and somebody that s traveling along the street can find a way to go from this end to anotheryu explains.
and the Institute for Molecular Engineering performed X-ray scattering studies using the Advanced Photon Source at Argonne
We take an approach where we actually make the luminescent active layer itself transparent. he solar harvesting system uses small organic molecules developed by Lunt
The Tour lab with assistance from the National Institute of Standards and Technology (NIST) produced the patented material that pulls only carbon dioxide molecules from flowing natural gas
Hwang also considered metal oxide frameworks that trap carbon dioxide molecules but they had the unfortunate side effect of capturing the desired methane as well
or nitrogen atoms) to start the polymerization reaction. This would never work on simple activated carbon; the key is that the polymer forms
and propane molecules that make up natural gas may try to stick to the carbon but the growing polymer chains simply push them off he says.
or nitrogen atoms evenly distributed through the resulting porous material. The sulfur-infused powder performed best absorbing 82 percent of its weight in carbon dioxide.
The US Department of energy (DOE) the SLAC National Accelerator Laboratory and the National Research Foundation of Korea helped support the study.
localized heating of the molecules leads to a temperature and pressure increase in the gas. f the incident light intensity is modulated,
As it moves along a carbon-nanotube track it continuously harvests energy from strands of RNA molecules vital to a variety of roles in living cells
and viruses. ur motors extract chemical energy from RNA molecules decorated on the nanotubes and use that energy to fuel autonomous walking along the carbon nanotube trackchoi says.
Inside that murky vial attached to the negative electrode bacteria feast on particles of organic waste
and convert it into biological fuel their excess electrons flow into the carbon filaments and across to the positive electrode
which is made of silver oxide a material that attracts electrons. The electrons flowing to the positive node gradually reduce the silver oxide to silver storing the spare electrons in the process.
After a day or so the positive electrode has absorbed a full load of electrons and has largely been converted into silver says Xing Xie an interdisciplinary researcher.
At that point it is removed from the battery and re-oxidized back to silver oxide releasing the stored electrons.
Engineers estimate that the microbial battery can extract about 30 percent of the potential energy locked up in wastewater.
With DNATRAX the bacteria is replaced by particles of non-biological DNA that can be collected with simple forensic swabs
By applying the DNA particles to the exterior of the suit it is possible to identify
since it comes in super fine particles. Previous methods of binding it to larger matter have already been used
Panasonic has found a way to bind the Tio2 to another particle zeolite (a commercial adsorbent and catalyst)
because the two particles are bound together by electrostatic force. When the novel photocatalytic particles are stirred Tio2 is released from the zeolite and dispersed throughout the water.
As a result reaction speed is much faster than other methods of fixing Tio2 on the surface of substrates
and fellow chemical engineers coated one-atom-thick tubes of carbon with protein fragments found in bee venom,
with the ability to detect even single molecules of the chemicals, and further, they can even detect the molecules the explosive chemicals form into as they break down.
The sensors can provide experts with a ingerprintof each explosive as well as the state of its breakdown.
and the team is still working out a compression system to ensure that any molecules in the air come into contact with the tubes
And we need to incorporate zero waste and low energy technologies into the task of food production. What can achieve the intensification of food supply we require,
#$150 smartphone spectrometer can tell the number of calories in your food If you wanted to look up the calorie content of a specific food you are eating you could take it to a lab and run it through a spectrometer.
But accurate spectrometers are huge, expensive machines that are owned often only by institutions and require training to use.
A new startup, however, wants to make it easy as running an app and pairing a bluetooth dongle.
In a few seconds, the associated smartphone app will take the spectrometer reading, send it to SCIO servers,
Other companies working in the portable spectrometer space have used also the technology to track calories eaten and nutritional intake through a user sweat.
and the principles of quantum mechanics are together allowing scientists to build virtual materials atom by atom.
Nature News A transparent, flexible electrode made from graphene could see a one-atom thick honeycomb of carbon first made just five years ago replace other high-tech materials used in displays.
The results in Hong's case were relatively large, high-quality films of graphene just a few atoms thick and several centimetres wide.
and by cooling the sample quickly after the reaction the researchers could produce up to ten single-atom layers of carbon in graphene's signature honeycomb pattern.
You can look at our technology as a high-speed gearbox that every few nanoseconds modulates the amount of power that the power amplifier draws from the battery explains Joel Dawson Eta Devices chief technology officer
which excites electrons that flow through the thylakoid membranes of the chloroplast. The plant captures this electrical energy
These particles are very strong antioxidants that scavenge oxygen radicals and other highly reactive molecules produced by light
and oxygen, protecting the chloroplasts from damage. The researchers delivered nanoceria into the chloroplasts using a new technique they developed called lipid exchange envelope penetration, or LEEP.
Wrapping the particles in polyacrylic acid a highly charged molecule, allows the particles to penetrate the fatty, hydrophobic membranes that surrounds chloroplasts.
In these chloroplasts, levels of damaging molecules dropped dramatically. Using the same delivery technique, 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,
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.
and boosted photosynthetic electron flow by about 30 percent. Yet to be discovered is how that extra electron flow influences the plantssugar production. his is a question that we are still trying to answer in the lab:
What is the impact of nanoparticles on the production of chemical fuels like glucose? Giraldo says.
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 enhance the function of living organisms in this case, plants, says James Collins, a professor of biomedical engineering at Boston University who was involved not in the research. he authors nicely show that self-assembling nanoparticles can be used to enhance the photosynthetic capacity of plants,
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,
#Nanoparticle network could bring fast-charging batteries (Phys. org) A new electrode design for lithium-ion batteries has been shown to potentially reduce the charging time from hours to minutes by replacing the conventional graphite electrode with a network of tin-oxide nanoparticles.
The anodes in most of today's lithium-ion batteries are made of graphite. The theoretical maximum storage capacity of graphite is limited very at 372 milliamp hours per gram hindering significant advances in battery technology said Vilas Pol an associate professor of chemical engineering at Purdue University.
Through this project Fan developed a faster way of treating the biochar particles using a new technology called plasma activation.
Double stranded-rna RNA is synthesized a molecule that can trigger a biological process known as RNA interference or RNAI to destroy the genetic code of an insect in a specific DNA sequence.
Our dsrna molecules were designed based on specific gene sequences of the mosquito Zhu said. You can design species-specific dsrna for the same or different genes for other insect pests.
and promises the ability to position functional biological molecules such as those involved in taste, smell,
In the study, the researchers used something called Atomic force microscopy (AFM), which is an imaging process that has a resolution down to only a fraction of a nanometer
However, instead of writing with fluid ink, we allow the lipid molecules the ink to dry on the tip first.
'which convert the detection of small molecules into electrical signals to stimulate our sense of smell. And many drugs work by targeting specific membrane proteins."
since 2001 and our technology has achieved now the fabrication of large area(>1000 mm2) ultra-thin films only a few atoms thick.
and receives electrons, but can also transfer them into another substance. Hydrogen is virtually everywhere on the planet,
and pump protons through a membrane, creating a form of chemical energy. They also know that water can be split into oxygen
The new material would need enough surface area to move electrons across quickly and evenly and boost the overall electron transfer efficiency.
The researchers also needed a platform on which biological components, like br, could survive and connect with the titanium dioxide catalyst:
which totally changes how the electrons move throughout our system.""Rozhkova's mini-hydrogen generator works like this:
Electrons from this reaction are transmitted to the titanium dioxide on which these two materials are anchored, making the titanium dioxide sensitive to visible light.
Simultaneously, light from the green end of the solar spectrum triggers the br protein to begin pumping protons along its membrane.
These protons make their way to the platinum nanoparticles which sit on top of the titanium dioxide. Hydrogen is produced by the interaction of the protons
and electrons as they converge on the platinum. Examinations using a technique called Electron Paramagnetic Resonance (EPR)
and time-resolved spectroscopy at the Center for Nanoscale Materials verified the movements of the electrons within the system,
while electrochemical studies confirmed the protons were transferred. Tests also revealed a new quirk of graphene behavior."
"The majority of the research out there states that graphene principally conducts and accepts electrons,
"said Argonne postdoctoral researcher Peng Wang.""Our exploration using EPR allowed us to prove, experimentally,
that graphene also injects electrons into other materials.""Rozhkova's hydrogen generator proves that nanotechnology,
merged with biology, can create new sources of clean energy. Her team's discovery may provide future consumers a biologically-inspired alternative to gasoline."
"This research,"Photoinduced Electron Transfer pathways in Hydrogen-Evolving Reduced graphene oxide-Boosted Hybrid Nano-Bio Catalyst,
Using the special properties of graphene a two-dimensional form of carbon that is only one atom thick a prototype detector is able to see an extraordinarily broad band of wavelengths.
Using a new operating principle called the hot-electron photothermoelectric effect the research team created a device that is as sensitive as any existing room temperature detector in the terahertz range
Graphene a sheet of pure carbon only one atom thick is suited uniquely to use in a terahertz detector
because when light is absorbed by the electrons suspended in the honeycomb lattice of the graphene they do not lose their heat to the lattice
Light is absorbed by the electrons in graphene which heat up but don't lose their energy easily.
These heated electrons escape the graphene through electrical leads much like steam escaping a tea kettle.
which conduct electrons at different rates. Because of this conductivity difference more electrons will escape through one than the other producing an electrical signal.
This electrical signal detects the presence of terahertz waves beneath the surface of materials that appear opaque to the human eye or even x-rays.
and low-cost biosensors that can eventually allow single-molecule detectionhe holy grail of diagnostics and bioengineering research said Samir Mitragotri co-author and professor of chemical engineering and director of the Center for Bioengineering at UCSB.
Graphene has been used among other things to design FETSEVICES that regulate the flow of electrons through a channel via a vertical electric field directed into the channel by a terminal called a gate.
and the current in the channel is modulated by the binding between embedded receptor molecules and the charged target biomolecules to
whose surface potential (or conductivity) can be modulated by the interaction (known as conjugation) between the receptor and target molecules that results in net accumulation of charges over the gate region.
Electrons travel freely across a graphene FETENCE it cannot be switched offhich in this case results in current leakages and higher potential for inaccuracies.
and label-free detection of biomoleculesemoving the step and expense of labeling target molecules with florescent dye.
a new class of nanoscale materials made in sheets only three atoms thick. The University of Washington researchers have demonstrated that two of these single-layer semiconductor materials can be connected in an atomically seamless fashion known as a heterojunction.
Collaborators from the electron microscopy center at the University of Warwick in England found that all the atoms in both materials formed a single honeycomb lattice structure, without any distortions or discontinuities.
and the evaporated atoms from one of the materials were carried toward a cooler region of the tube
After a while, evaporated atoms from the second material then attached to the edges of the triangle to create a seamless semiconducting heterojunction."
Under the guidance of Canada Research Chair in Materials science with Synchrotron radiation Dr. Alexander Moewes University of Saskatchewan researcher Adrian Hunt spent his Phd investigating graphene oxide a cutting-edge material that he hopes will shape the future
and SGM beamlines at the Canadian Light source as well as a Beamline 8. 0. 1 at the Advanced Light source Hunt set out to learn more about how oxide groups attached to the graphene lattice changed it
and how in particular they interacted with charge-carrying graphene atoms. Graphene oxide is fairly chaotic. You don't get a nice simple structure that you can model really easily but
Using the synchrotron Hunt could measure where electrons were on the graphene and how the different oxide groups modified that.
Moreover he studied how graphene oxide decays. Some of the oxide groups are not stable and can group together to tear the lattice;
These atom-thin sheets including the famed super material graphene feature exceptional and untapped mechanical and electronic properties.
and the material's nuclei and using DFT we can closely approximate real characteristics of the material under different conditions.
Within the honeycomb-like lattices of monolayers like graphene boron nitride and graphane the atoms rapidly vibrate in place.
As the perfect hexagonal structures of such monolayers are strained they enter a subtle soft mode the vibrating atoms slip free of their original configurations
and never returns that's like this soft mode where the vibrating atoms move away from their positions in the lattice.
As the monolayers were strained the energetic cost of changing the bond lengths became significantly weaker in other words under enough stress the emergent soft mode encourages the atoms to rearrange themselves into unstable configurations.
Engineers envision an electronic switch just three atoms thick More information: Eric B. Isaacs and Chris A. Marianetti.
It involves using a small glass pipette to pump a solution containing DNA into the nucleus of an egg cell,
One of the team's most significant findings is that it's possible to use the electrical forces to get DNA into the nucleus of the cellithout having to carefully aim the lance into the pronucleus (the cellular structure containing the cell's DNA."
The scientists took skin cells'nuclei the centers of the cells where the cells keep their DNA
Stick an adult nucleus into an unfertilized egg and you now essentially have a fertilized egg.
At least quantum physics is open to searching for this truth. As benign as this human cloning seems right now IT will be abused in the future.
Lancaster University chemists in collaboration with international colleagues have uncovered a'Crystal Nuclei Breeding Factory'which, they say,
"Previous experiments to understand the issue have been inconsequential as microscopes are just not strong enough to determine what the molecules are actually doing.
and Professor Lennart Lindfors, of Astrazeneca, Sweden, have mapped out'in diagram format the actual movements made by chemical molecules on their breeding journey using computer simulations.
The simulations rely on understanding the'forces'between the atoms from which they compute what the molecules do,
The journey involves the chemical molecules in solution forming clusters which on attaching to the crystal seed surface,
The'seeding'methodology allows you to separate correct molecules from rogue ones and to do this efficiently."
"The breakthrough also sheds light on the longstanding question of how the distinct'handedness'of molecules of life might have arisen.
Molecules of life exist in pairs that are mirror images of each other. Life forms appear to have selected molecules of only one of these mirror images (known as handedness)
and how this happened has challenged scientists for a long time.""Something happened early on in life so that one of the molecule mirror images dominated
and the whole of life was built on that, "says Professor Anwar. Current ideas are that molecules of one of the mirror images came together and led to a chance formation of a mirror crystal which, subsequently, induced massive crystallisation of the same image."
"Thanks to this study, we now know how such a single crystal seed could have amplified its effect
A defectree layer is also impermeable to all atoms and molecules. This amalgamation makes it a terrifically attractive material to apply to scientific developments in a wide variety of fields, such as electronics, aerospace and sports.
e transferred electrons from the dopant potassium to the surface of the black phosphorus, which confined the electrons
and allowed us to manipulate this state. Potassium produces a strong electrical field which is required what we to tune the size of the band gap. his process of transferring electrons is known as doping
and induced a giant Stark effect, which tuned the band gap allowing the valence and conductive bands to move closer together,
The team is currently working with industrial partners to create metasurfaces for use in commercial devices such as miniature cameras and spectrometers,
a chemical change triggers the generation of oxygen-carrying molecules known as reactive oxygen species (ROS). If a sunscreen agents penetrate the skin,
The nanoparticle hydrophilic layer essentially locks in the active ingredient, a hydrophobic chemical called padimate O. Some sunscreen solutions that use larger particles of inorganic compounds, such as titanium dioxide or zinc oxide,
These devices take advantage of the ability of electrons to penetrate barriers, a phenomenon known as quantum tunneling.
The new TFET is made from two atomically-thin layers of semiconducting molybdenum sulfide crystal on top of a substrate of germanium.
Made from carbon atoms arranged in a hexagonal sheet only one atom thick, graphene offers extraordinary properties:
These PDA particles capture pore-forming toxins such as those found in bee venom. Chen and Wang successfully discovered that the strong swimming mechanisms of their microfish actually enhanced the ability to clear up toxins,
#Researchers Evaluate Particle Retention and Stability on Nanomembrane Sheets In a new study, Cornell researchers examined these special nylon sheets replete with applied nanoscale iron oxide particles to see
if the particles wash loose. The particles work like magnets to capture bacteria and viruses,
and to extract chemicals or dye molecules out of water. Membranes with these particles attached could be used in devices to detect water contamination
or in filters to remove chemicals or dyes from industrial waste. However, to be effective and safe,
the particles need to stay on the membrane. The study evaluated the nanoparticle treatment uniformity and particle retention of the nylon membranes as they were processed
(or washed) in solutions of varying ph levels. t critical to evaluate particle retention and stability on fibers to reduce human health
and environmental concerns, said Nidia Trejo, a Cornell doctoral student in the field of fiber science.
Trejo, who with Margaret Frey, professor of fiber science, authored the study, comparative study on electrosprayed, layer-by-layer,
and chemically grafted nanomembranes loaded with iron oxide nanoparticles, in the Journal of Applied Polymer Science, July 14.
layer-by-layer assembly, where particles are coated on the fiber electrostatically; or chemical bonding. or the membrane, it important to evaluate particle retention and stability,
Trejo explained. ou would want the nanoparticles to stay on the Nylon 6 membranes so the material can have function throughout the life use.
you wouldn want the particles themselves to become pollutants if are they releasing from the membranes
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