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There’s filtration and then there’s filtration. Engineers in the US have been working on the latter, coming up with a new markedly more energy-efficient way of taking the salt out of seawater, which could deliver huge advantages in terms of providing people with access to drinking water and help combat problems like drought.

The researchers have developed a material that allows high volumes of water to pass through extremely tiny holes called ‘nanopores’ while blocking salt and other contaminants. The material they’re using – a nanometre-thick sheet of molybdenum disulphide (MoS2) riddled with these nanopore holes – is the most efficient of a number of thin-film membranes that the engineers modelled, filtering up to 70 percent more water than graphene.

“Even though we have a lot of water on this planet, there is very little that is drinkable,” said Narayana Aluru, a professor of mechanical science and engineering at the University of Illinois and leader of the study. “If we could find a low-cost, efficient way to purify sea water, we would be making good strides in solving the water crisis.”

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The world of superconductivity is in uproar. Last year, Mikhail Eremets and a couple of pals from the Max Planck Institute for Chemistry in Mainz, Germany, made the extraordinary claim that they had seen hydrogen sulphide superconducting at −70 °C. That’s some 20 degrees hotter than any other material—a huge increase over the current record.

Eremets and co have worked hard to conjure up the final pieces of conclusive evidence. A few weeks ago, their paper was finally published in the peer reviewed journal Nature, giving it the rubber stamp of respectability that mainstream physics requires. Suddenly, superconductivity is back in the headlines.

Today, Antonio Bianconi and Thomas Jarlborg at the Rome International Center for Materials Science Superstripes in Italy provide a review of this exciting field. These guys give an overview of Eremet and co’s discovery and a treatment of the theoretical work that attempts to explain it.

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ABSTRACT

The Mach Effect Thruster (MET) is a propellant―less space drive which uses Mach’s principle to produce thrust in an accelerating material which is undergoing mass―energy fluctuations, [1] –[3]. Mach’s principle is a statement that the inertia of a body is the result of the gravitational interaction of the body with the rest of the mass-energy in the universe. The MET device uses electric power of 100 — 200 Watts to operate. The thrust produced by these devices, at the present time, are small on the order of a few micro-Newtons. We give a physical description of the MET device and apparatus for measuring thrusts. Next we explain the basic theory behind the device which involves gravitation and advanced waves to incorporate instantaneous action at a distance. The advanced wave concept is a means to conserve momentum of the system with the universe. There is no momentun violation in this theory. We briefly review absorber theory by summarizing Dirac, Wheeler-Feynman and Hoyle-Narlikar (HN). We show how Woodward’s mass fluctuation formula can be derived from first principles using the HN-theory which is a fully Machian version of Einstein’s relativity. HN-theory reduces to Einstein’s field equations in the limit of smooth fluid distribution of matter and a simple coordinate transformation.

Keywords:

Mach Effect Drive, Transient Mass Fluctuations, Weak Field Limit Gravitation, Modified (PPN) Parameterized Post Newtonian Approximation, Linearized Einstein Equations, Gravitoelectromagnetism.

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Could an interactive swarm of flying “3D pixels” (voxels) allow users to explore virtual 3D information by interacting with physical self-levitating building blocks? (credit: Roel Vertegaal)

We’ll find out Monday, Nov. 9, when Canadian Queen’s University’s Human Media Lab professor Roel Vertegaal and his students will unleash their “BitDrones” at the ACM Symposium on User Interface Software and Technology in Charlotte, North Carolina.

Programmable matter

Vertegaal believes his BitDrones invention is the first step towards creating interactive self-levitating programmable matter — materials capable of changing their 3D shape in a programmable fashion, using swarms of tiny quadcopters. Possible applications: real-reality 3D modeling, gaming, molecular modeling, medical imaging, robotics, and online information visualization.

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South Korean scientists develop an electronic skin that uses a layer of graphene film to detect sound and temperature.

A team led by materials scientist at the Ulsan National Institute of Science and Technology in South Korea has developed rubbery plastic-and-graphene film that mimics the structure of human skin. The team claims that the film can accurately detect texture, temperature, pressure and sound. This marks the first time that an electronic skin has been able to demonstrate the ability to sense the entire spectrum of stimuli, and the team is hopeful that this technology can create practical artificial skin.

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Most science starts off at the fringe and slowly makes it way to the mainstream. Cryopreservation is commonly achieved in a laboratory setting, but for many years serious applications remained confined to science fiction. Is it time to change how we see cryonics?

The science of freezing things

Scientific research requires great storage, and huge amounts of material including cells are frozen every day to be used at the later date. If you follow the correct protocols, many forms of life can be re-awakened after their cryogenic sleep. DMSO, propylene glycol and glycerol help abolish problems like ice crystals which can rupture cells, and storage temperatures can drop to below −120 oC. At these levels biological reactions are essentially halted.

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A team of researchers with Ulsan National Institute of Science and Technology and Dong-A University, both in South Korea, has developed an artificial skin that can detect both pressure and heat with a high degree of sensitivity, at the same time. In their paper published in the journal Science Advances, the team describes how they created the skin, what they found in testing it and the other types of things it can sense.

Many scientists around the world are working to develop , both to benefit robots and human beings who have lost skin sensation or limbs. Such efforts have led to a wide variety of artificial skin types, but until now, none of them have been able to sense both pressure and heat to a high degree, at the same time.

The new artificial skin is a sandwich of materials; at the top there is a meant to mimic the human fingerprint (it can sense texture), beneath that sit sensors sandwiched between . The sensors are domed shaped and compress to different degrees when the skin is exposed to different amount of pressure. The compression also causes a small electrical charge to move through the skin, as does heat or sound, which is also transmitted to sensors—the more pressure, heat or sound exerted, the more charge there is—using a computer to measure the charge allows for measuring the degree of sensation “felt.” The ability to sense sound, the team notes, was a bit of a surprise—additional testing showed that the artificial skin was actually better at picking up sound than an iPhone microphone.

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