#New manufacturing approach slices lithium-ion battery cost in half An advanced manufacturing approach for lithium-ion batteries, developed by researchers at MIT and at a spinoff company called 24m,
promises to significantly slash the cost of the most widely used type of rechargeable batteries while also improving their performance
says Yet-Ming Chiang, the Kyocera Professor of Ceramics at MIT and a cofounder of 24m (and previously a cofounder of battery company A123).
The existing process for manufacturing lithium-ion batteries, he says, has changed hardly in the two decades
and colleagues including W. Craig Carter, the POSCO Professor of Materials science and engineering. In this so-called low battery, the electrodes are suspensions of tiny particles carried by a liquid
and pumped through various compartments of the battery. The new battery design is a hybrid between flow batteries and conventional solid ones:
In this version, while the electrode material does not flow, it is composed of a similar semisolid, colloidal suspension of particles.
Chiang and Carter refer to this as a emisolid battery. Simpler manufacturing process This approach greatly simplifies manufacturing,
and also makes batteries that are flexible and resistant to damage, says Chiang, who is senior author of a paper in the Journal of Power Sources analyzing the tradeoffs involved in choosing between solid
and flow-type batteries, depending on their particular applications and chemical components. This analysis demonstrates that
while a flow battery system is appropriate for battery chemistries with a low energy density (those that can only store a limited amount of energy for a given weight),
for high-energy density devices such as lithium-ion batteries, the extra complexity and components of a flow system would add unnecessary extra cost.
Almost immediately after publishing the earlier research on the flow battery, Chiang says, e realized that a better way to make use of this flowable electrode technology was to reinvent the lithium ion manufacturing process.
Instead of the standard method of applying liquid coatings to a roll of backing material, and then having to wait for that material to dry before it can move to the next manufacturing step,
the new process keeps the electrode material in a liquid state and requires no drying stage at all.
Using fewer thicker electrodes, the system reduces the conventional battery architecture number of distinct layers, as well as the amount of nonfunctional material in the structure, by 80 percent.
Having the electrode in the form of tiny suspended particles instead of consolidated slabs greatly reduces the path length for charged particles as they move through the material a property known as ortuosity.
A less tortuous path makes it possible to use thicker electrodes, which, in turn, simplifies production
and lowers cost. Bendable and foldable In addition to streamlining manufacturing enough to cut battery costs by half,
Chiang says, the new system produces a battery that is more flexible and resilient. While conventional lithium-ion batteries are composed of brittle electrodes that can crack under stress,
the new formulation produces battery cells that can be bent, folded or even penetrated by bullets without failing.
This should improve both safety and durability, he says. The company has made so far about 10,000 batteries on its prototype assembly lines, most
of which are undergoing testing by three industrial partners, including an oil company in Thailand and Japanese heavy-equipment manufacturer IHI Corp. The process has received eight patents
and has 75 additional patents under review; 24m has raised $50 million in financing from venture capital firms and a U s. Department of energy grant.
The company is initially focusing on grid-scale installations, used to help smooth out power loads
and provide backup for renewable energy sources that produce intermittent output, such as wind and solar power. But Chiang says the technology is suited also well to applications where weight
and volume are limited, such as in electric vehicles. Another advantage of this approach, Chiang says, is that factories using the method can be scaled up by simply adding identical units.
With traditional lithium-ion production plants must be built at large scale from the beginning in order to keep down unit costs,
so they require much larger initial capital expenditures. By 2020, Chiang estimates that 24m will be able to produce batteries for less than $100 per kilowatt-hour of capacity.
Venkat Viswanathan, an assistant professor of mechanical engineering at Carnegie mellon University who was involved not in this work, says the analysis presented in the new paper ddresses a very important question of
when is it better to build a flow battery versus a static model. This paper will serve as a key tool for making design choices
and go-no go decisions. Viswanathan adds that 24m new battery design ould do the same sort of disruption to lithium ion batteries manufacturing as
what mini-mills did integrated to the steel mills. i
#US Military to Develop its Own Hoverbike The US ARMY Research Laboratory has struck recently a deal with two companies, a UK-based start-up Malloy Aeronautics (MA) and Survice Engineering Co. SE),
to develop hoverbike technology for the US Department of Defence (Dod). MA hybrid hoverbike (a contraption most people associate with sci-fi novels and the Star wars movie franchise) looks more like a giant quadcopter drone than anything else two oak propellers in the front
and two in the back provide lift and thrust, with controls and a seat in the middle for a pilot.
The prototype, which was made from lightweight carbon fibre, combines the lifting power of a helicopter with the looks and feel of a motorcycle.
According to the company, its new hoverbike has a maximum takeoff weight of 270 kilograms and can log a distance of 148 kilometres on a single tank of gas.
The one-third scale prototype is controlled remotely and it likely that any full-scale model will have the option of flying without a human onboard,
too, making it not just a hoverbike, but a drone that a soldier can ride.
The project started as a hobby the engineer and MA founder Chris Malloy worked on in his garage at home in Sydney, Australia.
As time went by, however, several industries became interested and started making offers. The project completed a successful Kickstarter campaign last year, raising more than 100.000 dollars from 451 contributors.
To develop the bike in the US, MA teamed up with Survice, a Maryland-based defence contractor and engineering company.
The partnership was announced last week at the Paris Air Show. he Department of Defence is interested in hoverbike technology
because it can support multiple roles. It can transport troops over difficult terrain and when it not used in that purpose it can also be used to transport logistics, supplies,
ith adducted rotors you immediately not only protect people and property if you were to bump into them,
which has announced its plans to release a commercial version of the aircraft in 2017 with a sticker price of 85.000 US dollars.
In the meantime, Malloy Aeronautics will continue to make scale models while developing a commercial version of the hoverbike
and biologists at UC San diego have succeeded in designing and synthesizing an artificial cell membrane capable of sustaining continual growth, just like a living cell.
such as the ability to adapt their composition in response to environmental cues, said Neal Devaraj, an assistant professor of chemistry and biochemistry at UC San diego who headed the research team,
which included scientists from the campusbiocircuits Institute. any other scientists have exploited the ability of lipids to self-assemble into bilayer vesicles with properties reminiscent of cellular membranes,
The scientists said in their paper that to develop the growing membrane they substituted a omplex network of biochemical pathways used in nature with a single autocatalyst that simultaneously drives membrane growth.
higher energy building blocks into new artificial membranes. ur results demonstrate that complex lipid membranes capable of indefinite self-synthesis can emerge
when supplied with simpler chemical building blocks, said Devaraj. ynthetic cell membranes that can grow like real membranes will be an important new tool for synthetic biology and origin of life studies.
#Nanowire implants offer remote-controlled drug delivery A team of Purdue University researchers developed a new implantable drug-delivery system using the nanowires,
A team of researchers has created a new implantable drug-delivery system using nanowires that can be controlled wirelessly.
The nanowires respond to an electromagnetic field generated by a separate device, which can be used to control the release of a preloaded drug.
and wires required by other implantable devices that can lead to infection and other complications,
Purdue University Mari Hulman George Professor of Applied Neuroscience and director of Purdue Center for Paralysis Research. his tool allows us to apply drugs as needed directly to the site of injury,
which could have broad medical applications, Borgens said. he technology is in the early stages of testing,
but it is our hope that this could one day be used to deliver drugs directly to spinal cord injuries, ulcerations, deep bone injuries or tumors,
or chemotherapy. he team tested the drug-delivery system in mice with compression injuries to their spinal cords
The nanowires are made of polypyrrole, a conductive polymer material that responds to electromagnetic fields. Wen Gao, a postdoctoral researcher in the Center for Paralysis Research who worked on the project with Borgens,
grew the nanowires vertically over a thin gold base, like tiny fibers making up a piece of shag carpet hundreds of times smaller than a human cell.
The nanowires can be loaded with a drug and when the correct electromagnetic field is applied, the nanowires release small amounts of the payload.
This process can be started and stopped at will, like flipping a switch, by using the corresponding electromagnetic field stimulating device,
Borgens said. The researchers captured and transported a patch of the nanowire carpet on water droplets that were used used to deliver it to the site of injury.
The nanowire patches adhere to the site of injury through surface tension, Gao said. The magnitude and wave form of the electromagnetic field must be tuned to obtain the optimum release of the drug
and the precise mechanisms that release the drug are understood not yet well, she said. The team is investigating the release process.
The electromagnetic field is likely affecting the interaction between the nanomaterial and the drug molecules, Borgens said. e think it is a combination of charge effects
and the shape change of the polymer that allows it to store and release drugs,
he said. t is a reversible process. Once the electromagnetic field is removed, the polymer snaps back to the initial architecture
and retains the remaining drug molecules . or each different drug the team would need to find the corresponding optimal electromagnetic field for its release,
Gao said. This study builds on previous work by Borgens and Gao. Gao first had to figure out how to grow polypyrrole in a long vertical architecture,
which allows it to hold larger amounts of a drug and extends the potential treatment period.
The team then demonstrated it could be manipulated to release dexamethasone on demand. A paper detailing the work, titled ction at a Distance:
Functional Drug Delivery Using Electromagnetic field-Responsive Polypyrrole Nanowires, was published in the journal Langmuir. Other team members involved in the research include John Cirillo,
who designed and constructed the electromagnetic field stimulating system; Youngnam Cho, a former faculty member at Purdue Center for Paralysis Research;
and Jianming Li, a research assistant professor at the center. For the most recent study the team used mice that had been modified genetically such that the protein Glial fibrillary acidic protein,
or GFAP, is luminescent. GFAP is expressed in cells called astrocytes that gather in high numbers at central nervous system injuries.
Astrocytes are a part of the inflammatory process and form a scar tissue, Borgens said. A 1-2 millimeter patch of the nanowires doped with dexamethasone was placed onto spinal cord lesions that had been exposed surgically,
Borgens said. The lesions were closed then and an electromagnetic field was applied for two hours a day for one week.
By the end of the week the treated mice had a weaker GFAP signal than the control groups,
which included mice that were treated not and those that received a nanowire patch but were exposed not to the electromagnetic field.
In some cases, treated mice had no detectable GFAP signal. Whether the reduction in astrocytes had any significant impact on spinal cord healing
or functional outcomes was studied not. In addition, the concentration of drug maintained during treatment is known not
because it is below the limits of systemic detection, Borgens said. his method allows a very,
very small dose of a drug to effectively serve as a big dose right where you need it,
Borgens said. y the time the drug diffuses from the site out into the rest of the body it is in amounts that are undetectable in the usual tests to monitor the concentration of drugs in the bloodstream. olypyrrole is an inert and biocompatable material,
but the team is working to create a biodegradeable form that would dissolve after the treatment period ended,
he said. The team also is trying to increase the depth at which the drug delivery device will work.
The current system appears to be limited to a depth in tissue of less than 3 centimeters
#Researchers develop a new means of killing harmful bacteria The global rise in antibiotic resistance is a growing threat to public health,
damaging our ability to fight deadly infections such as tuberculosis. In this illustration, phagemid plasmids infect a targeted bacteria.
for new approaches to tackle bacterial infection. In a paper published online in the journal Nano Letters, researchers at MIT, the Broad Institute of MIT and Harvard,
and kill bacteria have been used for many years to treat infection in countries such as those in the former Soviet union.
But bacteriophages can also cause potentially harmful side effects, according to James Collins, the Termeer Professor of Medical Engineering and Science in MIT Department of Biological engineering and Institute of Medical Engineering and Science,
as it can lead to the release of nasty toxins from the cell. hese toxins can lead to sepsis and even death in some cases,
To build on this earlier work, the researchers set out to develop a related technology that would target
The researchers used synthetic biology techniques to develop a platform of particles called phagemids. These particles infect bacteria with small DNA molecules known as plasmids,
or peptides molecules made up of short chains of amino acids that are toxic to the bacteria,
Collins says. ou can use this to kill off very specific species of bacteria as part of an infection therapy,
in order to get a more effective therapy, he says. This is in contrast to repeated infection with bacteriophages,
where the researchers found that the bacteria did develop resistance over time. Although Collins acknowledges that bacteria will ultimately develop resistance to any stress that is placed upon them
the research suggests that it is likely to take them far longer to develop resistance to phagemids than to conventional bacteriophage therapy,
he says. A ocktailof different phagemids could be given to patients to treat an unclassified infection,
in a similar way to the broad-spectrum antibiotics used today. But they are more likely to be used in conjunction with rapid diagnostic tools, currently in development,
which would allow physicians to treat specific infections, Collins says. ou would first run a fast diagnostic test to identify the bacteria your patient has,
and then give the appropriate phagemid to kill off the pathogen, he says. The researchers are planning to expand their platform by developing a broader range of phagemids.
but now hope to create particles capable of killing off pathogens such as Clostridium difficile and the cholera-causing bacterium Vibrio cholerea.
The paper demonstrates that using synthetic biology to modify a gene in a phage to make it more toxic to a pathogen can lead to more effective antimicrobial particles than classical approaches,
says Alfonso Jaramillo, a professor of synthetic biology at the University of Warwick in the U k.,
who was involved not in the research. ombining synthetic genetic devices with phages as delivery vehicles allows a systematic approach to reprogram pathogenic bacteria for death,
as they are considered not genetically modified organisms, he says. The researchers have created an improved form of phage therapy that may become the antibiotics of the future,
he adds. Source: MIT, written by Helen Knigh f
#New approach holds promise for earlier, easier detection of colorectal cancer Caltech chemists develop a technique that could one day lead to early detection of tumors Chemists at Caltech
have developed a new sensitive technique capable of detecting colorectal cancer in tissue samples a method that could one day be used in clinical settings for the early diagnosis of colorectal cancer.
Colorectal cancer is the third most prevalent cancer worldwide and is estimated to cause about 700,000 deaths every year.
Metastasis due to late detection is one of the major causes of mortality from this disease; therefore, a sensitive and early indicator could be a critical tool for physicians and patients.
A paper describing the new detection technique currently appears online inchemistry & Biology and will be published in the July 23 issue of the journal print edition.
Caltech graduate student Ariel Furst (Phd 5) and her adviser, Jacqueline K. Barton, the Arthur and Marian Hanisch Memorial professor of chemistry, are the paper authors. urrently,
the average biopsy size required for a colorectal biopsy is about 300 milligrams, says Furst. ith our experimental setup,
we require only about 500 micrograms of tissue, which could be taken with a syringe biopsy versus a punch biopsy.
So it would be much less invasive. One microgram is one thousandth of a milligram.
but that has also recently been identified as an early indicator of cancer, especially the development of tumors,
if the process goes awry. When all is working well, DNMT1 maintains the normal methylation pattern set in the embryonic stages,
like suppress the growth of tumors or express proteins that repair damaged DNA, and that, in turn, can lead to cancer.
Building on previous work in Barton group, Furst and Barton devised an electrochemical platform to measure the activity of DNMT1 in crude tissue samples those that contain all of the material from a tissue
not just DNA or RNA, for example. Fundamentally, the design of this platform is based on the concept of DNA-mediated charge transport the idea that DNA can behave like a wire,
Barton earned the 2010 National Medal of Science for her work establishing this field of research
and has demonstrated that it can be used not only to locate DNA mutations but also to detect the presence of proteins such as DNMT1 that bind to DNA.
Furst and Barton started with two arrays of gold electrodes one atop the other embedded in Teflon blocks
They attached strands of DNA to the lower electrodes, then added the broken-down contents of a tissue sample to the solution well.
When they applied a current to the lower electrodes the samples with DNMT1 activity passed the current clear through to the upper electrodes,
where the activity could be measured. o methylation means cutting, which means the signal turns off,
each composed of a colorectal tumor sample and an adjacent healthy tissue from the same patient.
and the presence of cancer the correlation was with activity. he assay provides a reliable and sensitive measure of hypermethylation,
so this technique could provide a useful route to early detection of cancer when hypermethylation is involved.
portable tests that could be used in the home to catch colorectal cancer in its earliest, most treatable stages.
The work described in the paper, NA Electrochemistry shows DNMT1 Methyltransferase Hyperactivity in Colorectal Tumors, was supported by the National institutes of health a
#Risk of bowel cancer reduced by taking aspirin for Lynch syndrome patients An international study led by The University of Melbourne has confirmed that long-term regular taking of aspirin
or ibuprofen reduces the risk of bowel cancer by more than half for people with the genetic mutation causing Lynch syndrome.
At least 1 in 1000 people in the population have the genetic mutation that causes Lynch syndrome.
These people have a much higher rate of bowel cancer than the general population and about half would develop the disease without regular screening.
In a paper published in the Journal of the National Cancer Institute University of Melbourne researchers and international collaborators, led by Dr Driss Ait Ouakrim
and Dr Aung Ko Win from the School of Population and Global Health confirmed that those with Lynch syndrome who took aspirin regularly were less likely to develop bowel cancer than Lynch syndrome patients who did not take aspirin.
The research team also uncovered a new finding that Lynch syndrome patients who took ibuprofen regularly,
another nonsteroidal anti-inflammatory drug, were about 60%less likely to develop bowel cancer compared with those who did not take ibuprofen.
This protection was seen in both men and women. he main risk reduction method for these people is to have regular colonoscopy screening.
Almost nothing is known about if and how lifestyle factors and medications can modify their risk of bowel cancer,
Dr Win said. ur data is the first to confirm the finding of a previous international randomised clinical trial that found a protective effect of aspirin on bowel cancer for these high-risk people.
Also, we were able to show the similar protective effect of ibuprofen such as Nurofen on bowel cancer for people with Lynch syndrome,
Dr Win said
#Breakthrough in graphene production could trigger revolution in artificial skin development A pioneering new technique to produce high-quality,
low cost graphene could pave the way for the development of the first truly flexible lectronic skin that could be used in robots.
Researchers from the University of Exeter have discovered an innovative new method to produce the wonder material Graphene significantly cheaper,
The research team, led by Professor Monica Craciun, have used this new technique to create the first transparent and flexible touch-sensor that could enable the development of artificial skin for use in robot manufacturing.
Professor Craciun from Exeter Engineering department, believes the new discovery could pave the way for graphene-driven industrial revolutionto take place.
She said: he vision for a raphene-driven industrial revolutionis motivating intensive research on the synthesis of high quality and low cost graphene.
which grows graphene in an industrial cold wall CVD system, a state-of-the-art piece of equipment recently developed by UK graphene company Moorfield.
This so-called nanocvd system is based on a concept already used for other manufacturing purposes in the semiconductor industry.
This shows to the semiconductor industry for the very first time a way to potentially mass produce graphene with present facilities rather than requiring them to build new manufacturing plants.
Professor Seigo Tarucha from the University of Tokyo, coordinator of the Global Center of Excellence for Physics at Tokyo university and director of the Quantum Functional System Research Group at Riken Center
After starting the collaboration with Professor Craciun group, we are using Exeter CVD grown graphene instead of the exfoliated material in our graphene-based devices, whenever possible.
The research team used this new technique to create the first graphene-based transparent and flexible touch sensor.
The team believes that the sensors can be used not just to create more flexible electronics
but also a truly-flexible electronic skin that could be used to revolutionise robots of the future. Dr Thomas Bointon, from Moorfield Nanotechnology and former Phd student in Professor Craciun team at Exeter added:
merging flexible and wearable technologies such as healthcare electronics and energy harvesting devices could be transformed by the unique properties of graphene.
The extremely cost efficient procedure that we have developed for preparing graphene is of vital importance for the quick industrial exploitation of graphene.
At just one atom thick, graphene is the thinnest substance capable of conducting electricity. It is very flexible
and is one of the strongest known materials. The race has been on for scientists and engineers to adapt graphene for flexible electronics.
Professor Saverio Russo, co-author and also from the University of Exeter added: his breakthrough will nurture the birth of new generations of flexible electronics and offers exciting new opportunities for the realization of graphene-based disruptive technologies.
Source: University of Exete s
#Electrical engineers Break Power and Distance Barriers for Fiber optic communication Electrical engineers have broken key barriers that limit the distance information can travel in fiber optic cables
and still be deciphered accurately by a receiver. Photonics researchers at the University of California, San diego have increased the maximum power
and therefore distance at which optical signals can be sent through optical fibers. This advance has the potential to increase the data transmission rates for the fiber optic cables that serve as the backbone of the internet, cable wireless and landline networks.
The new study presents a solution to a longstanding roadblock to increasing data transmission rates in optical fiber:
beyond a threshold power level, additional power increases irreparably distort the information travelling in the fiber optic cable. oday fiber optic systems are a little like quicksand.
With quicksand, the more you struggle, the faster you sink. With fiber optics, after a certain point, the more power you add to the signal,
the more distortion you get in effect preventing a longer reach. Our approach removes this power limit,
which in turn extends how far signals can travel in optical fiber without needing a repeater, said Nikola Alic, a research scientist from the Qualcomm Institute, the corresponding author on the Science paper and a principal of the experimental effort.
In lab experiments the researchers at UC San diego successfully deciphered information after it travelled a record-breaking 12,000 kilometers through fiber optic cables with standard amplifiers and no repeaters,
which are electronic regenerators. The new findings effectively eliminate the need for electronic regenerators placed periodically along the fiber link.
These regenerators are effectively supercomputers and must be applied to each channel in the transmission. The electronic regeneration in modern lightwave transmission that carries between 80 to 200 channels also dictates the cost and,
more importantly, prevents the construction of a transparent optical network. As a result, eliminating periodic electronic regeneration will drastically change the economy of the network infrastructure
ultimately leading to cheaper and more efficient transmission of information. The breakthrough in this study relies on wideband requency combsthat the researchers developed.
The frequency comb described in this paper ensures that the signal distortions called the rosstalkthat arises between bundled streams of information travelling long distances through the optical fiber are predictable,
and therefore, reversible at the receiving end of the fiber. rosstalk between communication channels within a fiber optic cable obeys fixed physical laws.
It not random. We now have a better understanding of the physics of the crosstalk.
In this study, we present a method for leveraging the crosstalk to remove the power barrier for optical fiber
a professor in the Department of Electrical and Computer engineering at UC San diego and the senior author on the Science paper. ur approach conditions the information before it is sent even,
so the receiver is caused free of crosstalk by the Kerr effect. Pitch Perfect Data transmission The UC San diego researchersapproach is akin to a concert master who tunes multiple instruments in an orchestra to the same pitch at the beginning of a concert.
In an optical fiber, information is transmitted through multiple communication channels that operate at different frequencies. The electrical engineers used their frequency comb to synchronize the frequency variations of the different streams of optical information
called the ptical carrierspropagating through an optical fiber. This approach compensates in advance for the crosstalk that occurs between the multiple communication channels within the same optical fiber.
The frequency comb also ensures that the crosstalk between the communication channels is reversible. fter increasing the power of the optical signals we sent by 20 fold,
we could still restore the original information when we used frequency combs at the outset,
said UC San diego electrical engineering Ph d. student Eduardo Temprana, the first author on the paper. The frequency comb ensured that the system did not accumulate the random distortions that make it impossible to reassemble the original content at the receiver.
The laboratory experiments involved setups with both three and five optical channels, which interact with each other within the silica fiber optic cables.
The researchers note that this approach could be used in systems with far more communication channels. Most of today fiber optic cables include more than 32 of these channels,
which all interact with one another. In the Science paper, the researchers describe their frequency referencing approach to pre-compensate for nonlinear effects that occur between communication channels within the fiber optic cable.
when it is sent through the optical fiber. With the frequency comb the information can be unscrambled and fully restored at the receiving end of the optical fiber. e are preempting the distortion effects that will happen in the optical fiber,
said Bill Kuo, a research scientist at the Qualcomm Institute, who was responsible for the comb development in the group s
Overtext Web Module V3.0 Alpha
Copyright Semantic-Knowledge, 1994-2011