ECE GYAN

Bringing balance to the universe: New theory could explain missing 95 percent of the cosmos       Milky Way (stock image). Scientists at the University of Oxford may have solved one of the biggest questions in modern physics, with a new paper unifying dark matter and dark energy into a single phenomenon: a fluid which possesses 'negative mass'. If you were to push a negative mass, it would accelerate towards you. This astonishing new theory may also prove right a prediction that Einstein made 100 years ago. Our current, widely recognised model of the Universe, called LambdaCDM, tells us nothing about what dark matter and dark energy are like physically. We only know about them because of the gravitational effects they have on other, observable matter. This new model, published today in  Astronomy and Astrophysics , by Dr Jamie Farnes from the Oxford e-Research Centre, Department of Engineering Science, offers a new explanation. Dr Farnes says: ...

COSINE-100 experiment investigates dark matter mystery : COSINE-100's sodium-iodide detector array inside an acrylic tank lined with reflective foil. The tank was later filled with liquid scintillator to tag cosmic ray muons. Yale scientists are part of a new international experiment that challenges previous claims about the detection of non-luminous dark matter. Astrophysical evidence suggests that the universe contains a large amount of non-luminous dark matter, yet no definite signal of it has been observed despite concerted efforts by many experimental groups. One exception to this is the long-debated claim by the DArk MAtter (DAMA) collaboration, which has reported positive observations of dark matter in its sodium-iodide detector array. The new COSINE-100 experiment, based at an underground, dark-matter detector at the Yangyang Underground Laboratory in South Korea, has begun to explore DAMA's claim. It is the first experiment sensitive enough to test...

On the trail of the Higgs Boson : The elusive particle won't share all the secrets of its creation mechanism at once. For the physics community, the discovery of new particles like the Higgs Boson has paved the way for a host of exciting potential experiments. Yet, when it comes to such an elusive particle as the Higgs Boson, it's not easy to unlock the secrets of the mechanism that led to its creation. The experiments designed to detect the Higgs Boson involve colliding particles with sufficiently high energy head-on after accelerating them in the Large Hadron Collider (LHC) at CERN in Geneva, Switzerland. In a quest to understand the production mechanisms for the Higgs Boson, Silvia Biondi from the National Institute of Nuclear Physics, Bologna, Italy investigated the traces of a rare process, called ttH, in which the Higgs Boson is produced in association with a pair of elementary particles referred to as top quarks. Her findings can be found in a recent study p...

New attack could make website security captchas obsolete : Researchers have created new artificial intelligence that could spell the end for one of the most widely used website security systems. The new algorithm, based on deep learning methods, is the most effective solver of captcha security and authentication systems to date and is able to defeat versions of text captcha schemes used to defend the majority of the world's most popular websites. Text-based captchas use a jumble of letters and numbers, along with other security features such as occluding lines, to distinguish between humans and malicious automated computer programmes. It relies on people finding it easier to decipher the characters than machines. Developed by computer scientists at Lancaster University in the UK as well as Northwest University and Peking University in China, the solver delivers significantly higher accuracy than previous captcha attack systems, and is able to successfully crack versions...

High-temperature electronics? That's hot : A new organic plastic allows electronics to function in extreme temperatures without sacrificing performance. From iPhones on Earth to rovers on Mars, most electronics only function within a certain temperature range. By blending two organic materials together, researchers at Purdue University could create electronics that withstand extreme heat. This new plastic material could reliably conduct electricity in up to 220 degrees Celsius (428 F), according to a paper published Thursday in the journal  Science . "Commercial electronics operate between minus 40 and 85 degrees Celsius. Beyond this range, they're going to malfunction," said Jianguo Mei, a professor of organic chemistry at Purdue University. "We created a material that can operate at high temperatures by blending two polymers together." One of these is a semiconductor, which can conduct electricity, and the other is a conventional...

Method to transfer entire 2D circuits to any smooth surface : Illustration of flexible, 2-D circuit. What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that. Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices to report on what they perceive. Electronically active 2D materials have been the subject of much research since the introduction of graphene in 2004. Even though they are often touted for their strength, they're difficult to move to where they're needed without destroying them. The Ajayan and Lou groups, along with the lab of Rice engineer Jacob Robinson, have a new way to keep the materials and their associated circuitry, including electrodes, intact as they're moved to curved or other smooth surfaces. The results of their work appear in t...

Molecular adlayer produced by dissolving water-insoluble nanographene in water : "Nanographene incorporated micelle capsules" can be prepared by simply pulverizing and mixing nanographene with amphiphilic V-shaped anthracene molecules in water at room temperature. Even though nanographene is insoluble in water and organic solvents, Kumamoto University (KU) and Tokyo Institute of Technology (Tokyo Tech) researchers have found a way to dissolve it in water. Using "molecular containers" that encapsulate water-insoluble molecules, the researchers developed a formation procedure for a nanographene adlayer, a layer that chemically interacts with the underlying substance, by just mixing the molecular containers and nanographene together in water. The method is expected to be useful for the fabrication and analysis of next-generation functional nanomaterials. Graphene is a single layer of carbon atoms arranged in sheet form. It is lighter than metal wit...

Electro chemical techniques for monitoring microbial growth demonstrated : Electrochemical techniques are being used to define microorganisms as electrochemical entities and thereby provide opportunities to monitor microbial activity in real time, in-situ. This approach is expected to decrease analytical costs while providing an abundance of data for industrial bioprocesses. Savannah River National Laboratory, in collaboration with Clemson University, the University of South Carolina and Savannah River Consulting LLC, has demonstrated the use of electrochemical techniques to monitor the growth status and energy levels of microorganisms used in biotechnology industries. As published in a recent  Applied Microbiology and Biotechnology Express article, the techniques monitor the microbes in real time, improving the cost-effectiveness of the results compared to conventional sampling and analysis. Microorganisms are used in many industrial applications, including product...

Borophene advances as 2D materials platform : Atom-thin sheets of boron containing large single crystals could provide foundation for fabricating next-generation electronics. A schematic of hexagonal networks of boron atoms (pink), which are found on the hexagonal nodes and periodically in the center of the hexagon, grown on a surface of copper atoms (brown). The scientists used a low-energy electron microscope (LEEM) to watch "islands" of borophene (yellow triangles in left circle) grow, changing the temperature, deposition rate, and other growth conditions in real time to refine the "recipe." The islands can sit on the surface in six different orientations and can be discriminated by selecting an electron diffraction spot (such as the one circled in yellow) corresponding to a particular orientation (the one connected with the dotted line). Eventually the islands grow to such an extent that they touch and meet, and the entire surface (one centimeter squar...

Team converts wet biological waste to diesel-compatible fuel : Mechanical science and engineering graduate student Timothy Lee holds a sample of waste and a sample of distillate the team derived from that waste. In a step toward producing renewable engine fuels that are compatible with existing diesel fuel infrastructure, researchers report they can convert wet biowaste, such as swine manure and food scraps, into a fuel that can be blended with diesel and that shares diesel's combustion efficiency and emissions profile. The researchers report the findings in the journal  Nature Sustainability . "The demonstration that fuels produced from wet waste can be used in engines is a huge step forward for the development of sustainable liquid fuels," said Brajendra K. Sharma, a research scientist with the Illinois Sustainable Technology Center at the University of Illinois' Prairie Research Institute and a co-author of the study. U. of I. agricultur...

Reflecting antiferromagnetic arrangements : Brookhaven Lab physicists Claudio Mazzoli (left) and Mark Dean at the Coherent Soft X-ray Scattering (CSX) beamline at the National Synchrotron Light Source II. Mazzoli and Dean are part of the team of scientists led by Rutgers University that used the CSX beamline to image some magnetic domains in an iron-based 'antiferromagnetic' material. The ability to image these domains is key to developing spintronics, or spin electronics, for practical applications. A team led by Rutgers University and including scientists from the U.S. Department of Energy's (DOE) Brookhaven National Laboratory has demonstrated an x-ray imaging technique that could enable the development of smaller, faster, and more robust electronics. Described in a paper published on Nov. 27 in  Nature Communications , the technique addresses a primary limitation in the emerging research field of "spintronics," or spin electronics, using magneti...

First observation of a square lattice of merons and antimerons : Scientists have, for the first time, observed a square lattice of merons and antimerons -- tiny magnetic vortices and antivortices that form in a thin plate of the helical magnet Co8Zn9Mn3. By finely varying a magnetic field applied perpendicularly to the thin plate, the researchers were able to induce a transformation between the square lattice of merons-antimerons and a hexagonal lattice of skyrmions, another form of vortex that is topologically different from merons and antimerons. The ability to manipulate nanometer-scale spin textures such as merons and skyrmions is a key to the development of spintronics -- next-generation electronic devices that are very low in power consumption. The secret to their low power consumption is that they make use of the topological spin texture -- a property that emerges when electrons interact in a solid. To perform the experiments, published in  Nature , the group us...