20 most recent innovations in chemistry

Graphene ‘biofoam’ Makes Filthy Water Drinkable

Thu, 11 Aug 2016 00:00:00 Z

Engineers have found a way to use graphene oxide sheets to transform dirty water into drinking water.

The new approach combines bacteria-produced cellulose and graphene oxide to form a bi-layered biofoam.

The new biofoam is extremely light and inexpensive to make, making it a viable tool for water purification and desalination.

Coating Highlights Microscopic Cracks

Tue, 19 Jan 2016 00:00:00 Z

Whether they're on airplanes, bridges or pipelines, even the tiniest of cracks can fast lead to catastrophic failures. That's why it's important to identify them as early as possible, before they get out of hand. With that in mind, scientists at the University of Illinois have created a new polymer coating that can be applied to a wide variety of structural materials. When those materials crack – even a little – the polymer changes color to let inspectors know that something's up.

Designed by a team led by professors Nancy Sottos and Scott White, the polymer contains epoxy resin microcapsules filled with a light-yellow pH-sensitive dye.

As long as no damage occurs, those capsules remain intact. However, should a crack form (as small as 10 micrometers in width), the capsules in that area burst and release the dye. That dye chemically reacts with the epoxy, changing from yellow to bright red in color. The larger the crack, the greater the amount of dye reacts, and the more pronounced the color-change.

According to the researchers, the polymer has been successfully tested on materials including metal, glass and other polymers. It's also reasonably inexpensive, as it only needs to be composed of five percent microcapsules in order to work effectively.

Along with other possible applications, they're now looking at incorporating the polymer into a self-healing plastic that they previously created. In that case, an initial color-change would indicate that a crack had formed, while a secondary change would indicate that it had subsequently healed.

Using Shock Waves to Separate Salty Water From Fresh

Mon, 16 Nov 2015 00:00:00 Z

A team from MIT has developed a way to desalinate water using shock waves, which could significantly reduce the amount of energy currently used to purify salt water.

The technology, called shock electrodialysis, forces a shock wave of electrical current that pushes the flowing, salty water through a porous, glass material and a sandwich of membranes or electrodes. As the current moves through the system, the salt water is separated into areas of salt depletion or salt enriched. And when the electrical current reaches a critical point, a shock wave is created that divides the flow of water by creating a “barrier” that separates the fresh water from the salty water.

Paint That Fends Off Damage And Heat

Mon, 07 Sep 2015 00:00:00 Z

Sunlight can be brutal. It wears down even the strongest structures, including rooftops and naval ships, and it heats up metal slides and bleachers until they’re too hot to use. To fend off damage and heat from the sun’s harsh rays, scientists have developed a new, environmentally friendly paint out of glass that bounces sunlight off metal surfaces — keeping them cool and durable.

“Most paints you use on your car or house are based on polymers, which degrade in the ultraviolet light rays of the sun,” says Jason J. Benkoski, Ph.D. “So over time you’ll have chalking and yellowing. Polymers also tend to give off volatile organic compounds, which can harm the environment. That’s why I wanted to move away from traditional polymer coatings to inorganic glass ones.”

Glass, which is made out of silica, would be an ideal coating. It’s hard, durable and has the right optical properties. But it’s very brittle.

To address that aspect in a new coating, Benkoski, who is at the Johns Hopkins University Applied Physics Lab, started with silica, one of the most abundant materials in the earth’s crust. He modified one version of it, potassium silicate, that normally dissolves in water. His tweaks transformed the compound so that when it’s sprayed onto a surface and dries, it becomes water resistant.

Unlike acrylic, polyurethane or epoxy paints, Benkoski’s paint is almost completely inorganic, which should make it last far longer than its counterparts that contain organic compounds. His paint is also designed to expand and contract with metal surfaces to prevent cracking.

Mixing pigments with the silicate gives the coating an additional property: the ability to reflect all sunlight and passively radiate heat. Since it doesn’t absorb sunlight, any surface coated with the paint will remain at air temperature, or even slightly cooler. That’s key to protecting structures from the sun.

“When you raise the temperature of any material, any device, it almost always by definition ages much more quickly than it normally would,” Benkoski says. “It’s not uncommon for aluminum in direct sunlight to heat 70 degrees Fahrenheit above ambient temperature. If you make a paint that can keep an outdoor surface close to air temperature, then you can slow down corrosion and other types of degradation.”

In fact, the paint Benkoski’s lab is developing is intended for use on naval ships. But it has many other potential commercial applications.

“You might want to paint something like this on your roof to keep heat out and lower your air conditioning bill in the summer,” he says. It could even go on metal playground slides or bleachers. And it would be affordable. The materials needed to make the coating are abundant and inexpensive.

Benkoski says he expects his lab will start field testing the material in about two years.

Continuous Liquid Interface 3D Printer

Tue, 17 Mar 2015 00:00:00 Z

This new 3D printing technology looks like science fiction. But it's entirely real — the scientists who created it were inspired by the futuristic liquid metal in the movie Terminator 2.

Joseph DeSimone and the other University of North Carolina scientists who describe it in a new paper published today in Science call it "continuous liquid interface production." (They've also founded a new company called Carbon3D to sell the printer.)

Unlike conventional 3D printing, their printer continuously forms a new object, rather than printing it in layers. As a result, they say, it's much faster than conventional 3D printing (it takes minutes, instead of hours).

This could finally bring the big advantage of 3D printing — that it lets you easily customize or tweak designs by making changes to software, rather than building new manufacturing machines — to mass consumer products.

Magnetic Field Reduces Beer Foam

Thu, 18 Dec 2014 00:00:00 Z

It’s every beer drinker’s worst nightmare: You set your bottle down on a table and open it, only for the drink to foam up and come shooting out, drenching the table and most likely you as well. But that nightmare might soon become a thing of the past thanks to an unlikely source: magnets.

Belgian researchers have used magnets to make beer less foamy. Applying a magnetic field made antifoaming agents more effective. The field is applied when hops extract is added to beer's malt base. This prevents it from attracting too much CO2 - which causes foam.

The method was so effective that much lower amounts of hops extract were needed, reducing the cost of brewing the beer in the first place. The method takes just one minute and could make beer cheaper - as less hops extract is needed to prevent the formation of foam

UV Liquid Plastic Welder

Wed, 17 Dec 2014 00:00:00 Z

Perhaps you've had one or more of the following experiences when trying to stick items together using super glue: the glue sets before the objects can be properly aligned, it won't set fast enough, or it hardens inside the bottle once it's been opened. Well, Bondic is claimed to have none of those problems. It's described as a "liquid plastic welder" that sets within four seconds, but only once it's been exposed to an included UV light.

First of all, adhesives that are cured using ultraviolet light have indeed been around for some time. They typically require users to supply their own UV light, however, and thus are usually limited to industrial or even medical applications.

By contrast, Bondic comes with its own UV LED that sits on the end of a reusable cartridge filled with the liquid plastic.

The liquid is applied via a needle-type applicator, to items made out of materials including plastic, metal, fiberglass or wood. It can then be worked with until users have got everything set up the way they wish. They then just shine the light on the liquid for four seconds, which is reportedly all that's required to cause it to harden.

Along with simply joining things together, this technique also allows successive layers of the plastic to be laid down one on top of another, in order to fill gaps. Once a gap is filled, the hardened plastic can be sanded, polished or painted as needed.

Glove Shows Its True Colors

Fri, 30 Aug 2013 00:00:00 Z

Researchers at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT in Regensburg have engineered a glove that recognizes if toxic substances are present in the surrounding air.

The protective glove is equipped with custom-made sensor materials and indicates the presence of toxic substances by changing colors. In this regard, the scientists adapted the materials to the corresponding analytes, and thus, the application. The color change – from colorless (no toxic substance) to blue (toxic substance detected), for example – warns the employee immediately. “By synthesizing the adapted color sensor materials, we can detect gases like carbon monoxide, for example, or hydrogen sulfide. Still, this protective gear represents only one potential area of application. Sensor materials could also be deployed for the quick detection of leaks in gas lines,” explains Dr. Sabine Trupp, head of the Fraunhofer EMFT Sensor Materials group.

Highly Absorbent Polymer

Thu, 22 Aug 2013 00:00:00 Z

The most talented creative minds can draw connections between seemingly unrelated things—like diapers and a field of crops--in order to produce new solutions. That's how Mexican chemical engineer Sergio Jesus Vaelasco created Solid Rain, a highly absorbent polymer scientifically known as potassium polyacrylate. Originally intended to make diapers more absorbent, Vaelasco's blend can soak up water to about 500 times its size, and it looks like large salt crystals:

For landscape architects and environments designers it could mean more creative options for plants in drought-heavy areas. Solid Rain could ensure that green landscapes exist and thrive even in water-scarce urban areas, and other places where greenery has a tougher time surviving and so is conspicuously missing.

Impossible material "Upsalite"

Tue, 30 Jul 2013 00:00:00 Z

In science, nothing is impossible, only highly improbable. But that doesn't stop scientists from celebrating a new discovery or creation previously deemed impossible. Researchers from Uppsala University in Sweden, have published results about the creation of a new supposedly impossible material that they are calling "Upsalite." Upsalite is a magnesium carbonate material that has already broken world records with its surface area and water absorption abilities.

According to previous scientific research, ordered forms of magnesium carbonate occur in nature, but water-free disordered forms have been difficult to make. However, Johan Goméz de la Torre, researcher at the Nanotechnology and Functional Materials Division has now figured out that magnesium carbonate can be created in a simple, low-temperature process.

As with many great scientific discoveries, this new development occurred because of a mistake. Attempting to work from previous experiment data, some test material was accidentally left in a reaction chamber over a weekend. When the scientists returned to work on Monday morning, they discovered that it had formed into a rigid gel. They dried the gel and realized they had created something previously not thought possible. This led to a year of fine tuning and analysis, along with a host of other experiments. After going through a number of state of the art materials characterization techniques, it became clear that they had actually synthesized an impossible material.

Perhaps the most surprising discovery, though, was the properties of this new material. Upsalite has the highest surface area measured for an alkali earth metal carbonate: 800 square meters per gram. This puts the material in a very exclusive class of porous, high surface area materials that includes silica, zeolites, metal organic frameworks and carbon nanotubes. The research team also found that the material was filled with empty pores, which gives it a unique way of interacting with the environment. For example, Upsalite can absorb more water at low relative humidities than any other currently available material.

These unique properties could lead to Upsalite being useful in a variety of industrial applications, including the collection of toxic waste, chemicals, and oil spills. It could also prove useful for drug delivery systems, odor control, and sanitation after a fire.

Nanoscavengers for water purification

Wed, 22 May 2013 00:00:00 Z

WHO and UNICEF have set a 2030 target for everyone to have access to a safe drinking-water supply and new water-purifying “nanoscavengers” developed by researchers at Stanford University could help achieve this goal. There are various nanoparticles that boast different water-purifying properties. Silver nanoparticles act as an antibiotic, titanium dioxide nanoparticles trap heavy metals and pollutants, while others capture salt. Engineers call these kinds of particles nanoscavengers.

The main problem has been reclaiming the nanoscavengers from the water once they have performed their clean up duties. Some approaches that are already in use commercially involve giving the nanoscavengers a core of iron oxide to make them magnetic, meaning they can then be removed using magnets. The downside of this method is that it isn’t possible to remove all the nanoscavengers because iron oxide isn’t absolutely responsive to magnetism.

To overcome this problem, the Stanford team developed a new type of nanoscavenger that sees the iron oxide core replaced with a synthetic core. This new core is a disk made up of magnetic outer layers sandwiched either side of a titanium center. This composition makes the new nanoscavengers non-magnetic in their natural state, so they aren’t attracted to each other or other magnetic materials.

However, when the synthetic core is exposed to a strong magnetic field, the magnetism of the two opposing fields align so they not only become magnetic, but the magnetic effect is compounded to make them ultraresponsive to magnetism.

In a side-by-side test against the aforementioned iron oxide core nanoscavengers, the synthetic core nanoscavengers killed 99.9 percent of the E. coli bacteria in 20 minutes and allowed virtually all of the nanoscavengers to be removed from the water after a five minute exposure to a permanent magnet.

Non-explosive chemical fertilizer

Thu, 02 May 2013 00:00:00 Z

The use of ammonium nitrate in IEDs is so widespread that the Joint Improvised Explosive Device Defeat Organization (JIEDDO) last year put out a call for ideas on ways to neutralize ammonium nitrate as an IED explosive. It’s a difficult task because its legal use is so common. Even though ammonium nitrate fertilizer is illegal in Afghanistan for example, it is easily sourced from neighboring Pakistan, where agriculture accounts for a quarter of the country’s gross domestic product.

Knowing that in ammonium nitrate the ammonium ion is weakly attracted to the nitrate ion, and that the right chemical reaction can pull them apart, researchers decided to look for a compound they would rather cling to that could be added to the ammonium nitrate. They tried several materials, including iron sulfate, a readily available compound discarded by the ton from steel foundries.

If someone attempts to alter the ammonium nitrate/iron sulfate mixture to make it detonable by mixing it with fuel, the iron ion takes the nitrate ion and the ammonium ion takes the sulfate ion. The result is that the iron sulfate becomes iron nitrate and the ammonium nitrate becomes ammonium sulfate, neither of which is detonable.

But the new compound wouldn’t be much use if it weren’t also a good fertilizer. Thankfully, it is. In fact, the addition of iron sulfate to the mix makes the new fertilizer even better than ammonium nitrate for alkaline soils.

Envelope X Ray Spray

Thu, 21 Mar 2013 00:00:00 Z

Envelope X-RAY Spray turns opaque paper temporarily translucent, allowing the user to view the contents of an envelope without ever opening it. 30 seconds after the application, the envelope will return to its original state, leaving absolutely no markings, discoloration, or other indications of use. Each can treats several hundred square inches. Non-conductive and non-photochemically reactive. Environmentally-friendly

Liquid marbles detect gases

Wed, 26 Sep 2012 00:00:00 Z

Australian researchers have used the porous effects of liquid marbles to turn a scientific frustration into a driving force to develop new gas sensors.

Liquid marbles are formed by encapsulating a liquid drop with hydrophobic particles, making a spherical shell that stops the liquid core from coming into contact with other surfaces. Most research focuses on liquid transport applications, but problems have arisen owing to the porous nature of the liquid marble allowing the liquid core to evaporate.

Now, Wei Shen and colleagues at Monash University in Clayton have discovered a new use for them. By exploiting the fact that the liquid marble shell will allow gas but not liquid to diffuse through, they have produced ammonia and hydrochloric acid gas sensors. 'The liquid marble shell is a natural gas-liquid separator which has important application implications,' explains Shen. 'The liquid marbles can be used to sense, absorb, or emit gas.'

Shen used the concept to produce colorimetric liquid marble ammonia sensors using phenolphthalein, CoCl2, and CuCl2 solutions as liquid cores encapsulated with Teflon powder, which successfully changed colour on exposure to the gas. And 8-hydroxypyrene-1,3,6- trisulfonic acid trisodium salt (HPTS) indicator was used as the liquid core to create fluorescent sensors for hydrochloric acid vapour.

'It is a truly new idea' comments Robert Pelton, an expert in interfacial technologies at McMaster University, Hamilton, Canada. 'It's a really good example of creative synthesis of disparate elements in the literature - marble preparation and chemical analysis.'

Shen now plans to increase the mechanical stability of the liquid marbles and find an easy way to quantitatively detect the sensing results. He hopes that this research will 'generate new ideas in pharmaceutical research, superhydrophobic research, separation applications and in low-cost equipment-free sensor design.'

New coating technology for self-cleaning cars

Mon, 23 Jul 2012 00:00:00 Z

Researchers at The Netherlands’ Eindhoven University of Technology (TU/e) have developed a coating that is not only self-healing, but also promises to free car owners of the tiresome chore of washing the car.

While coatings with highly water-resistant or antibacterial properties are nothing new, their applications have been limited as they can easily lose these properties. This is because the nano-sized molecular groups that provide these properties are easily and irreversibly damaged by minor contact with the surface on which they are applied.

Researcher Catarina Esteves of the department of Chemical Engineering and Chemistry at TU/e and her colleagues claim to have solved this problem with the development of surfaces that place the functional chemical groups at the end of special “stalks” that are mixed through the coating. When the outer surface layer is removed by scratching, the “stalks” in the layer underneath re-orient themselves to the new surface to restore their function.

The researchers say this will enable the creation of highly water-resistant coatings that could be applied to cars so that superficial scratches heal themselves and water droplets roll off the car, taking dirt with them. This would mean, instead of taking the car to a car wash or getting junior to earn some pocket money, all that would be required to keep the car beaming is the occasional rain shower.

Besides doing away with some Mr. Miyagi-style Karate training, the technology could also be used in self-healing mobile phone displays, solar panels and contact lenses. The researchers say that aircraft using the self-cleaning technology would benefit from reduced fuel consumption due to the cleaner surface providing less air resistance, while ships could employ it to prevent the build up of algae on their hulls. It would also reduce the frequency with which aircraft and ships need repainting.

Smart, Self-Healing Hydrogels Repair Themselves After Sustaining Damage

Wed, 07 Mar 2012 00:00:00 Z

The ability to heal--to repair oneself repeatedly and thus sustain damage repeatedly--is one of biology’s greatest tricks, and one that humans have been trying to replicate in synthetic materials for years. Now, bioengineers at University of California, San Diego, have done so via a hydrogel that could be something of a game-changer in disciplines like medicine and materials science.

Hydrogels are semi-solid, gummy-bear-like squishy materials made of chains of hydrophilic polymer molecules. That hydrophilic quality makes them a good analog for natural tissues because, due to their high water content, they tend to mimic the flexibility and other textural qualities of biological media. As such, they are often used in medical applications--as scaffolds for tissue engineering, for instance, or as drug delivery systems--but thus far attempts to make them repair themselves after a cut or tear is introduced have come up short.

The UCSD team found that the key to making hydrogels self-heal was creating a means by which polymer chains that have been cut can find and latch onto each other. Then they set to work making it happen via mechanisms they call "dangling side chain" molecules, which are pretty much exactly what they sound like. Like fingers hanging from the main structure of the polymer chains, they give a chain that’s been damaged something to grab on to. Through computer simulations, the team found that the length of these dangling side chains plays a crucial role in the ability to self-heal, and that by optimizing this length they could make a hydrogel with a surprisingly strong ability for self-repair.

Further, the strength of the bond established when one of the hydrogels self-heals can be manipulated by the pH level of a surrounding solution. So, for instance, in an environment with low pH the hydrogel fuses rather strongly, while at higher pH levels the bond is weakened. That characteristic makes it ideal for working in applications where acid is present, whether that’s suturing up a perforated stomach or creating a protective lining for containers that hold caustic, acidic materials.

Of course, that only makes sense for the particular hydrogel the team has in the lab now. Next, the bioengineers hope to create a variety of hydrogels that fuse and separate at different pH values, widening their applications to environments that aren’t necessarily acidic. Such hydrogels could potentially lead to a new generation of self-healing plastics and other synthetic materials that can sustain and bounce back from repeated damage, just like the human body.

Cloth makes short work of bacteria

Thu, 06 Oct 2011 00:00:00 Z

There are many ways to kill bacteria – those microscopic life forms that sometimes do bring harm to us in their very own special way, which explains why we have different kinds of defenses against these in the form of disinfectants, antibiotics and other kinds of chemical warfare. Well, here is a little something that might just aid us in our fight against these nigh invisible opponents – a new kind of cloth developed that is self-cleaning, where it kills bacteria in the process whenever it is exposed to sunlight.

Yes sir, you no longer need to worry too much about the kind of laundry powder to kill bacteria the next time you put your washing machine through another cycle as chemists at the University of California at Davis might have discovered a compound known as 2-AQC, where it will be incorporated into cotton fabrics. Whenever said infused fabrics are exposed to light, it ends up with a reaction, producing oxygen species such as hydrogen peroxide that will make short work of bacteria while breaking down toxins.

See Through Organs

Wed, 05 Oct 2011 00:00:00 Z

A new chemical reagent called Scale is able to make biological tissues transparent, allowing researchers to more easily study the marked cells within.

Dr. Atsushi Miyawaki led the team that created the reagent, which they used to make the brain tissue of test mice clear. The team was able to see into the tissue at a depth of several millimeters, and were able to observe the "axons connecting the left and right hemispheres...in greater detail than ever before."

Miyawaki believes the reagent should work equally as well on other organs, and allow for experiments that have never been possible before.

Petri Dish Gets a Makeover

Thu, 25 Aug 2011 00:00:00 Z

A new type of diagnostic could let hospital laboratories identify the presence of dangerous bacteria up to five times faster than conventional methods. The test could reduce unnecessary antibiotic use and provide more reliable water-quality test results. The key to the process is a membrane with nanosized pores, which enable rapid growth and identification of live organisms.

The new technology, developed by Hubbard, Ohio-based Nanologix, speeds up the process by wicking bacteria and viruses through the pores of its membrane, aiding growth. Then the membrane is plucked off the agar and placed on a staining plate.

Using Metamaterials to Manipulate Light

Fri, 12 Aug 2011 00:00:00 Z

According to reports, engineers from Duke University have developed a metamaterial that allows them to control the direction and frequency of light.

The current proof-of-concept device is about the size of a hardback book, and consists of parallel rows of individual pieces made of fiberglass and etched with copper circles. A diode spans a tiny gap in each circle and creates non-linearity when it is excited by microwave radiation passing through it. This allows the light to be controlled at will.

If the reports are accurate, this development is an important step toward the creation of a optical switcher that could dramatically increase transmission speed of data streams at a lower consumption of energy.