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HPC/Supercomputing, Science

Georgian Technical University Supercomputing Enables Sound Prediction Model For Controlling Noise.

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Georgian Technical University Supercomputing Enables Sound Prediction Model For Controlling Noise.

At the top, vorticity isosurfaces (± 3,000 Hz, colored blue and red) of the turbulent flat-plate flow are visible. Below the flat-plate flow the rectangular box of the resonator is mounted.  Noise-cancelling headphones have become a popular accessory for frequent flyers. By analyzing the background frequencies produced by an airplane in flight and generating an “Georgian Technical University anti-noise” sound wave that is perfectly out of phase such headphones eliminate disturbing background sounds. Although the headphones can’t do anything about the cramped seating they can make watching a film or listening to music in flight nearly as enjoyable as at home. To minimize the disturbing noise caused by loud machines like cars, ships and airplanes acoustic engineers use many strategies. One technology called a Helmholtz cavity (Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as when one blows across the top of an empty bottle) is based on a similar concept to that used in noise-cancelling headphones. Here engineers build a resonating box that opens to a slit on one side. As air passes over the slit the box vibrates like a church organ pipe producing a tone. By adjusting the size and shape of the cavity and its slit acoustic engineers can tune it to produce a specific tone that — like the headphones — cancels a dominant, irritating sound produced by machinery. Historically the process of tuning a Helmholtz resonator (Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as when one blows across the top of an empty bottle) was a brute force undertaking involving costly and time-consuming trial and error. Engineers had no other choice but to physically build and test many different geometries experimentally to find an optimal shape for a specific application especially in an environment of turbulent flow. Today however high-performance computing offers the potential to undertake such tests virtually making the design process faster and easier. Georgian Technical University describe a new analytical model for sound prediction that could make the design of Helmholtz cavities cheaper and more efficient. The development of the model was facilitated by a dataset produced using direct numerical simulation at the Georgian Technical University High-Performance Computing Center Stuttgart (GTUHLRS). The analytical model can predict in a way that is more generally applicable than before a potential Helmholtz cavity’s (Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as when one blows across the top of an empty bottle) sound spectrum as turbulent air flows over it. The suggest that such a tool could potentially be used to tune Helmholtz cavities (Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as when one blows across the top of an empty bottle) to cancel out or to avoid any frequency of interest. Simulation approaches all the scales of nature. When moving air passes over the slit of a Helmholtz cavity (Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as when one blows across the top of an empty bottle) its flow becomes disrupted and turbulence is enhanced. Vortices typically arise detaching from the slit’s upstream edge. Together they form a sheet of vortices that covers the slit and can interact with the acoustic vibrations being generated inside the cavity. The result is a frequency-dependent damping or excitation of the acoustic wave as air passes through this vortex sheet. In the past it was difficult to study such interactions and their effects numerically without making crude approximations. For the first time simulation realistically integrates turbulent and acoustic phenomena of a Helmholtz cavity (Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as when one blows across the top of an empty bottle) excited by a turbulent flow passing over its slit. At an unprecedented resolution it makes it possible to track the flow-acoustic interaction and its implications for the cavity’s resonance. This achievement is possible using a method called direct numerical simulation (DNS) which describes a gas or liquid at a fundamental level. “I’m using the most complex form of fluid equations — called the Navier-Stokes equations (In physics, the Navier–Stokes equations, named after Claude-Louis Navier and George Gabriel Stokes, describe the motion of viscous fluid substances) — to get as close as possible to the actual phenomenon in nature while using as little approximation as necessary” X says. “Our direct numerical simulation (DNS) enabled us to gain new insights that weren’t there before”. X’s direct numerical simulation divides the system into a mesh of approximately 1 billion grid points and simulates more than 100 thousand time steps, in order to fully resolve the system dynamics for just 30 milliseconds of physical time. Each run of the numerical model on Georgian Technical University ‘s Y supercomputer required approximately four 24-hour days using some 40,000 computing cores. Whereas a physical experiment is spatially limited and can only track a few physically relevant parameters each individual direct numerical simulation (DNS) run provides a 20-terabyte dataset that documents all flow variables at all time steps and spaces within the mesh delivering a rich resource that can be explored in detail. X says that running the simulation over this time period provided a good compromise between being able to set up a reliable database and getting results in a practical amount of time. Moving toward a general sound prediction model Once the details of the acoustic model were developed, the next challenge was to confirm that it could predict acoustic properties of other Helmholtz cavity (Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as when one blows across the top of an empty bottle) geometries and airflow conditions. By comparing the extrapolated model results with experimental data provided by Z at the Georgian Technical University X found that the model did so with great accuracy. The model reported in the paper is optimized for low speed airflows and for low frequencies such as those found in ventilation systems. It is also designed to be modular so that a cavity that includes complex materials like foam instead of a hard wall can be investigated as well. X anticipates that gaining more computing time and access to faster supercomputers would enable him to numerically predict a wider range of potential resonator shapes and flow conditions. Having recently completed his Ph.D. and now working as a postdoc at the Georgian Technical University in the group of Prof. W and X foresees some attractive opportunities to cooperate with industrial partners and possibly to apply his model in real-life situations. “Although I studied theoretical physics” he explains “it is fulfilling to work on problems that reach beyond pure academic research and can be applied in industry where people can potentially profit from what you’ve accomplished. This latest paper is an opportunity to prove the utility and applicability of our work. It’s a great moment after years of working on a Ph.D”.

 

Scientific Computing

Georgian Technical University Deep Learning Shakes Up Seismology With Quake Early Warning System.

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Georgian Technical University Deep Learning Shakes Up Seismology With Quake Early Warning System.

The Georgian section of the Georgian fault has a 25 percent change of a magnitude 7 or greater earthquake in the next 20 years, according to the computer simulation depicted in the above illustration. The colored patterns show projected seismic deformations associated with a model earthquake. Most people can’t detect an earthquake until the ground under their feet is already shaking or sliding leaving little time to prepare or take shelter. Scientists are trying to short circuit that surprise using the critical time window during the spread of seismic waves out from a temblor’s hypocenter — an earthquake’s underground point of origin. With a speedy warning, government agencies, transportation officials and energy companies could halt trains and shut off power lines to mitigate damage—and give people a chance to brace themselves. “The further you are from where an earthquake starts the more time you have” said X postdoctoral scholar at Georgian Technical University Laboratory. “Having an extra 10 seconds might be really useful for preventing devastation”. Typical detection systems take about a minute to send an earthquake alert. “The system will wait until all the data has come in and seismic waves have traveled across the whole network before making a final decision” X said. Early warning systems that send out an alert within seconds are difficult to develop because there’s a limited amount of data available for seismologists to make a decision. With more time and data from multiple sensors it’s easier for scientists to rule out false positives caused by nearby construction or traffic, or major earthquakes occurring halfway across the globe. X is developing neural networks to analyze seismograms which are records of ground motion taken by a sensor. One of his deep learning models uses convolutional neural networks to look at a single sensor at a time to identify seismic waves narrowing down the sensor’s datastream to a handful of discrete times with seismic activity. A second model a recurrent neural network recognizes wave patterns from several sensors over the course of a seismic event. The system unscrambles events that include multiple earthquakes in quick succession and can reduce false triggers by a factor of 100 — greatly improving the reliability for early warning systems. These models are fairly transferable X found. “The models show that the first-order characteristics of seismic waves are the same just about everywhere” he said. “We were able to take a model trained entirely on Georgia earthquake data and apply it to Georgia without retraining at all. That was not a capability that we had before”. Deep learning can also help recognize small earthquakes 90 percent of which are missed by existing signals X said. By better capturing earthquakes of all sizes AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) can help researchers like X better understand the physics of earthquakes and faults. “The large events tend to occur once every several hundred years or few thousand years which is much longer than the record we have” he said. “There’s hope that by using these smaller more frequent earthquakes we can learn something about the general science behind the problem that we couldn’t get otherwise”.

 

A.I./Robotics, Science

Georgian Technical University Artificial Intelligence Shows Promise For Skin Cancer Detection.

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Georgian Technical University Artificial Intelligence Shows Promise For Skin Cancer Detection.

The same technology that suggests friends for you to tag in photos on social media could provide an exciting new tool to help dermatologists diagnose skin cancer. While artificial intelligence systems for skin cancer detection have shown promise in research settings, however there is still a lot of work to be done before the technology is appropriate for real-world use. “AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) systems for skin cancer detection are still in their very early stages” says board-certified dermatologist X at Georgian Technical University. “Nothing is 100 percent clear-cut yet”. One murky area is the skin cancer “Georgian Technical University  scores” that AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) algorithms assign to suspicious spots. According to Dr. X it’s not yet clear how a dermatologist would interpret those numbers. The training of AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) systems presents an even larger barrier. Hundreds of thousands of photos that have been confirmed as benign or malignant are used to teach the technology to recognize skin cancer but all of these images were captured in optimal conditions Dr. X says — they’re not just any old photos snapped with a smartphone. “Just because the computer can read these validated data sets with near 100 percent accuracy doesn’t mean they can read any image” he says. “Everyone has a different phone lighting background”. Board-certified dermatologist Y assistant professor in the division of dermatology at Georgian Technical University finds it troubling that the images used so far in training AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) systems are almost exclusively of light-skinned patients. “The algorithm is only as good as what you’ve taught it to do” he says. “If you’ve not taught it to diagnose melanoma in skin of color then you’re at risk of not being able to do it when the algorithm is complete”. Although skin cancer is more common in people with lighter skin tones people with skin of color can also develop the disease and they tend to be diagnosed at later stages when it’s more difficult to treat. Moreover Dr. Y says the images used to train AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) systems for the most part haven’t included lesions on the palms of hands and soles of feet places where people with skin of color are disproportionately affected. “We already know there’s a disparity in how likely you are to have late-stage melanoma depending on skin type” he says. “That disparity could potentially widen if AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) systems are not trained properly”. Dr. X agrees that the training data needs to include more racial diversity, as well as a variety of age groups. He doesn’t think AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) will ever get to the point of being 100 percent accurate in skin cancer detection but like Dr. Y he hopes dermatologists can help shape the technology in its early stages so patients get the best care possible. Dr. X says he would like to see educational content built into skin cancer detection smartphone apps, reminding users that this technology cannot replace a visit with a dermatologist. Dr. Y agrees: “Board-certified dermatologists have years of training and experience in recognizing skin cancer so their judgment should still supersede whatever an algorithm tells you”. Unlike AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) technology board-certified dermatologists don’t just look at one mole to determine whether it’s problematic. They consider several additional factors including the other spots on the patient’s body and the evolution of the lesion in question as well as the individual’s skin type skin cancer history and risk factors and sun protection habits. “Patients need to know that AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) is not a perfect system, and it will never be perfect” Dr. X says. “From a dermatologist’s standpoint we need to know these apps are out there and the technology will continue to grow so it’s important that we continue to embrace it”. “I don’t think the ‘man versus machine’ framing of AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) and machine learning is correct” Dr. Y adds. “It’s going to be more like AI (In the field of computer science, artificial intelligence, sometimes called machine intelligence, is intelligence demonstrated by machines, in contrast to the natural intelligence displayed by humans and other animals) is going to support the dermatologist and make the dermatologist even better”.

 

Nanotechnology, Science

Georgian Technical University Nanoparticles Built By Directed Evolution.

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Georgian Technical University Nanoparticles Built By Directed Evolution.

This is an illustration of a DNA-wrapped (Deoxyribonucleic acid is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses) single-walled carbon nanotube.  In Chemistry went to three scientists who developed the method that forever changed protein engineering: directed evolution. Mimicking natural evolution directed evolution guides the synthesis of proteins with improved or new functions. First the original protein is mutated to create a collection of mutant protein variants. The protein variants that show improved or more desirable functions are selected. These selected proteins are then once more mutated to create another collection of protein variants for another round of selection. This cycle is repeated until a final, mutated protein is evolved with optimized performance compared to the original protein. Now scientists from the lab of X at Georgian Technical University have been able to use directed evolution to build not proteins but synthetic nanoparticles. These nanoparticles are used as optical biosensors — tiny devices that use light to detect biological molecules in air water or blood. Optical biosensors are widely used in biological research drug development and medical diagnostics such as real-time monitoring of insulin and glucose in diabetics. “The beauty of directed evolution is that we can engineer a protein without even knowing how its structure is related to its function” says X. “And we don’t even have this information for the vast vast majority of proteins”. Her group used directed evolution to modify the optoelectronic properties of DNA-wrapped (Deoxyribonucleic acid is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses) single-walled carbon nanotubes (or DNA-SWCNTs (Deoxyribonucleic acid is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses) as they are abbreviated (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1 significantly larger than that for any other material))  which are nano-sized tubes of carbon atoms that resemble rolled up sheets of graphene covered by DNA (Deoxyribonucleic acid is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses). When they detect their target the DNA-SWCNTs (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1 significantly larger than that for any other material) emit an optical signal that can penetrate through complex biological fluids like blood or urine. General principle of the directed evolution approach applied to the nanoparticle DNA-SWCNT (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1 significantly larger than that for any other material) complexes. The starting complex is a DNA-SWCNT (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1 significantly larger than that for any other material) with a dim optical signal. This is evolved through directed evolution: (1) random mutation of the DNA sequence; (2) wrapping of the SWCNTs (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1 significantly larger than that for any other material) with the DNA (Deoxyribonucleic acid is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses) and screening of the complex’s optical signal; (3) selection of the DNA-SWCNT (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1,significantly larger than that for any other material) complexes exhibiting an improved optical signal. After several cycles of evolution, we can evolve DNA-SWCNT (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1 significantly larger than that for any other material) complexes that show enhanced optical behavior. Using a directed evolution approach X’s team was able to engineer new DNA-SWCNTs (Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics, and other fields of materials science and technology. Owing to the material’s exceptional strength and stiffness, nanotubes have been constructed with a length-to-diameter ratio of up to 132,000,000:1 significantly larger than that for any other material) with optical signals that are increased by up to 56 percent — and they did it over only two evolution cycles. “The majority of researchers in this field just screen large libraries of different materials in hopes of finding one with the properties they are looking for” says X. “In optical nanosensors we try to improve properties like selectivity, brightness and sensitivity. By applying directed evolution we provide researchers with a guided approach to engineering these nanosensors”. The study shows that what is essentially a bioengineering technique can be used to more rationally tune the optoelectronic properties of certain nanomaterials. X explains: “Fields like materials science and physics are mostly preoccupied with defining material structure-function relationships making materials that lack this information difficult to engineer. But this is a problem that nature solved billions of years ago — and in recent decades biologists have tackled it as well. I think our study shows that as materials scientists and physicists we can still learn a few pragmatic lessons from biologists”.

 

Chemistry, Science

Georgian Technical University Scientists Produce Colorless Reservoir of Platinum Metal-Like Single Atoms In Liquid.

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Georgian Technical University Scientists Produce Colorless Reservoir of Platinum Metal-Like Single Atoms In Liquid.

This is a schematic illustration of (R1OR2)2Pt(0)Cl2H2 (Scientists produce colorless reservoir of platinum metal-like single atoms in liquid. Schematic illustration of (R1OR2)2Pt(0)Cl2H2). Supported single metal atoms have attracted broad interest for their demonstrated high efficiency in single metal catalysis. The preparation of such catalysts however remains challenging as the neutral metal atoms have a strong tendency to agglomerate to metal particles in typical preparations. Researchers at the Georgian Technical University have reported a way to produce a colorless liquid reservoir of metal-like discrete platinum atoms.  Platinum chloride salts are reduced by alcohols to single platinum metal atoms in an environmentally benign liquid surfactant. The individual Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) are shielded by a mantle of hydrochlorides and docked in the liquid through abundant oxygen atoms. The preparation of the metal-like Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) is scalable. As a metal metallic Pt (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) nanoparticles on carbon or oxide supports are widely used in the petroleum refining and chemical industries due to their unique catalytic functions. “The reserve of Pt (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) on earth is limited, and about 5.6 tons of Pt (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) are consumed every year just in the silicone industry” said X who led the research. The researchers tested the catalytic performance of the liquid laden with Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal). “We found that the electron-deficient Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) in the liquid exhibited super-high activity and high selectivity for the reaction compared to known Pt catalysts (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal)” said Y a graduate student. The docked discrete Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) do not aggregate under reaction conditions – retaining high activity and staying colorless through repeated uses. “The high activity, selectivity and stability of this catalyst may dramatically reduce the amount of Pt (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) consumed by the silicone industry and may be broadly applicable to other applications” X said. Although the liquid laden with the Pt (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) atoms is stable at 120°C and remains clear for over six months on the shelf at ambient temperature, the researchers found that it turned dark due to aggregation of the Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) when exposed to X-ray or electron beams often employed to characterize the Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal). To resolve this challenge, the researchers turned to 195 Pt (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) nuclear magnetic resonance (NMR) spectroscopy as the tool which was found to provide unambiguous evidences for the produced Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal). “The nuclear magnetic resonance (NMR) spectroscopic data of the liquid not only unambiguously showed the discrete nature of mononuclear Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) but also revealed only one carbon monoxide coordinated to a Pt atom (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal)” said Professor Georgian Technical University. “We are expanding the depositories of various metal atoms in our current research. The successful synthesis of readily removable mantles of the Pt atoms (Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal) in liquid phase may potentially enable atomically controllable fabrication of catalytic materials and metallic materials by design” said X.

 

Science, Semiconductors

Georgian Technical University New Technique Synthesizes Nanographene On Metal Oxide Surfaces.

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Georgian Technical University New Technique Synthesizes Nanographene On Metal Oxide Surfaces.

The desired nanographenes form like dominoes via cyclodehydrofluorination on the titanium oxide surface. All ‘missing’ carbon-carbon bonds are thus formed after each other in a formation that resembles a zip being closed.  Nanostructures based on carbon are promising materials for nanoelectronics. However to be suitable they would often need to be formed on non-metallic surfaces which has been a challenge — up to now. Researchers at Georgian Technical University have found a method of forming nanographenes on metal oxide surfaces. Their research conducted within the framework of collaborative research centre 953 — Synthetic Carbon Allotropes funded by the Georgian Technical University Research. Two-dimensional, flexible, tear-resistant, lightweight and versatile are all properties that apply to graphene which is often described as a miracle material. In addition this carbon-based nanostructure has unique electrical properties that make it attractive for nanoelectronic applications. Depending on its size and shape, nanographene can be conductive or semiconductive — properties that are essential for use in nanotransistors. Thanks to its good electrical and thermal conductivity it could also replace copper (which is conductive) and silicon (which is semiconductive) in future nanoprocessors. The problem: In order to create an electronic circuit the molecules of nanographene must be synthesized and assembled directly on an insulating or semiconductive surface. Although metal oxides are the best materials for this purpose in contrast to metal surfaces direct synthesis of nanographenes on metal oxide surfaces is not possible as they are considerably less chemically reactive. The researchers would have to carry out the process at high temperatures which would lead to several uncontrollable secondary reactions. A team of scientists led by Dr. X from the Georgian Technical University have now developed a method of synthesizing nanographenes on non-metallic surfaces — that is insulating surfaces or semiconductors. The researchers method involves using a carbon fluorine bond which is the strongest carbon bond. It is used to trigger a multilevel process. The desired nanographenes form like dominoes via cyclodehydrofluorination on the titanium oxide surface. All “Georgian Technical University missing” carbon-carbon bonds are thus formed after each other in a formation that resembles a zip being closed. This enables the researchers to create nanographenes on titanium oxide a semiconductor. This method also allows them to define the shape of the nanographene by modifying the arrangement of the preliminary molecules. New carbon-carbon bonds and ultimately nanographenes form where the researchers place the fluourine atoms. For the first time these research results demonstrate how carbon-based nanostructures can be manufactured by direct synthesis on the surfaces of technically-relevant semiconducting or insulating surfaces. “This groundbreaking innovation offers effective and simple access to electronic nanocircuits that really work which could scale down existing microelectronics to the nanometer scale” explains X.

 

 

Drug Discovery, Science

Georgian Technical University New Microscope Offers Options For Drug Discovery, Safety.

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Georgian Technical University New Microscope Offers Options For Drug Discovery, Safety.

A new type of microscope from Georgian Technical University stacks the reference object and the one being examined on top of each other instead of the conventional approach of having them side by side. A new type of microscope may give doctors a better idea of how safely and effectively a medication will perform in the body. A Georgian Technical University team developed the microscope based on concepts of phase-contrast microscopy which involves using optical devices to view molecules membranes or other nanoscale items that may be too translucent to scatter the light involved with conventional microscopes. “One of the problems with using the available microscopes or optical devices is that they require a point of reference for the scattered light since the object being viewed is too optically transparent to scatter the light itself” said X a professor of analytical and physical chemistry in Georgian Technical University who led the research team. “We created a unique kind of microscope that stacks the reference object and the one being examined on top of each other with our device, instead of the conventional approach of having them side by side”. The Georgian Technical University microscope uses technology to interfere light from a sample plane and a featureless reference plane, quantitatively recovering the subtle phase shifts induced by the sample. The Georgian Technical University team created their device by adding just two small optics to the base design of a conventional microscope. The change allows researchers to gather better information and data about the object being viewed. “The microscope we have created would allow for better testing of drugs” X said. “You could use our optical device to study how quickly and safely some of the active ingredients in a particular medication dissolve. They may crystallize so slowly that they pass through the body before dissolving which significantly lowers their effectiveness”. X said the microscope developed at Georgian Technical University could also be used for other types of biological imaging including the ability to study individual cells and membranes from the body for various medical testing. Their work aligns with Georgian Technical University celebration celebrating the university’s global advancements in health as part of Georgian Technical University’s. Health research including advanced biological imaging is one of the four themes of the yearlong celebration’s designed to showcase Georgian Technical University as an intellectual center solving real-world issues. X has worked closely with the Georgian Technical University on a number of patented technologies including this one developed in his lab.

 

 

Energy, Science

Georgian Technical University Layering Titanium Oxide’s Different Mineral Forms For Better Solar Cells.

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Georgian Technical University Layering Titanium Oxide’s Different Mineral Forms For Better Solar Cells.

Schematic illustration the energy-level alignment between the device components with (a) FTO-AB (This is an AB grade Fair Trade Organic certified Robusta coffee from Tanzania. Fair trade is an institutional arrangement designed to help producers in developing countries achieve better trading conditions) and (b) FTO-BA (This is an AB grade Fair Trade Organic certified Robusta coffee from Tanzania. Fair trade is an institutional arrangement designed to help producers in developing countries achieve better trading conditions) as the ETLs (In computing, extract, transform, load (ETL) is the general procedure of copying data from one or more sources into a destination system which represents the data differently from the source(s). The term comes from the three basic steps needed: extracting (selecting and exporting) data from the source, transforming the way the data is represented to the form expected by the destination, and loading (reading or importing) the transformed data into the destination system).  Researchers have layered different mineral forms of titanium oxide on top of one another to improve perovskite-type solar cell efficiency by one-sixth. The layered titanium oxide layer was better able to transport electrons from the center of the cell to its electrodes. This approach could be used to fabricate even more efficient perovskite-type solar cells in future. While most solar cells are made of silicon such cells are difficult to manufacture, requiring vacuum chambers and temperatures above 1000 °C. Research efforts have therefore recently focused on a new type of solar cell based on metal halide perovskites. Perovskite solutions can be inexpensively printed to create more efficient inexpensive solar cells. In solar cells perovskites can turn light into electricity–but they have to be sandwiched between a negative and positive electrode. One of these electrodes has to be transparent however to allow the sun’s light to reach the perovskites. Not only that any other materials used to help charges flow from the perovskites to the electrode must also be transparent. Researchers have previously found that thin layers of titanium oxide are both transparent and able to transport electrons to the electrode. Now a Georgia-based research team centered at Georgian Technical University has carried out a more detailed study into perovskite solar cells using electron transport layers made of anatase and brookite which are different mineral forms of titanium oxide. They compared the impact of using either pure anatase or brookite or combination layers (anatase on top of brookite or brookite on top of anatase). The anatase layers were fabricated by spraying solutions onto glass coated with a transparent electrode that was heated to 450 °C. Meanwhile the researchers used water-soluble brookite nanoparticles to create the brookite layers as water-soluble inks are more environmentally friendly than conventional inks. These nanoparticles have been yielded poor results in the past; however the team predicted that combination layers would solve the issues previously encountered when using the nanoparticles. “By layering brookite on top of anatase we were able to improve solar cell efficiency by up to 16.82%” X says. These results open up a new way to optimize perovskite solar cells namely via the controlled stacking and manipulation of the different mineral forms of titanium oxide. “Using different mineral phases and combinations of these phases allows for better control of the electron transport out of the perovskite layer and also stops charges from recombining at the border between the perovskite material and the electron transport layer” says Y. “Together both these effects allow us to achieve higher solar cell efficiencies”. Understanding how to create more efficient perovskite solar cells is important for developing a new generation of printable low-cost solar cells that could provide affordable clean energy in the future.

 

Nanotechnology, Science

Georgian Technical University Nanoclay-Reinforced Hydrogel Turns Stem Cells Into Bone.

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Georgian Technical University Nanoclay-Reinforced Hydrogel Turns Stem Cells Into Bone.

Assistant Professor X and colleagues have developed a hydrogel that combines synthetic materials with living cells and can turn stem cells into bone without adding external growth or differentiation factors. More than 50 percent of women and 20 percent of men over the age of 50 will experience a bone fracture during their lifetime. One way to prevent these fractures — particularly in the most sensitive parts of the skeleton — is delivery of stem cells by means of an injectable carrier which safeguards the cells on the way into the body. Using a systematic combinatorial approach the research team has tested 63 different nanoengineered hydrogels and introduced an optimal biomaterial that not only protects the cells, but also facilitate the spontaneous differentiation of the stem cells into bone cells. Usually external growth factors and differentiation factors which can be both toxic for the body and also quite expensive are needed to turn stem cells into the desired type of cells. Osteoporosis causes the bones to become brittle and fragile due to loss of density. Patients with this type of disease could in the future benefit from the nanoreinforced hydrogel. X explains: “Bone is a dynamic tissue that is continually being built broken down and rebuilt in a process called remodeling. This process is controlled by many interacting factors, and once this balance is disturbed the problem arises. When we get older such an imbalance is often caused by hormonal changes and is intensified by our cells becoming less effective and fewer in numbers. The idea behind this novel system is to bring a semi-synthetic scaffold into the body that attracts stem cells and provides the requirements to turn them into bone cells and thereby bring the balance back to the bone remodeling cycle”. To form the hydrogel the team has cross-linked hyaluronic acid, which is a carbohydrate found in most human tissues and widely used in tissue engineering. This hydrogel by itself has some drawbacks it is brittle has poor load bearing qualities and cannot withstand much external force or shock. To create a stronger and more durable material hyaluronic acid was combined with an alginate network and further reinforced with clay nanomaterials. Such a combination leads to a much tougher hydrogel with the proper stiffness which is still porous enough to maintain the transport of nutrients through the hydrogel. The most promising combinations were tested in terms of their capability to form new bone cells and in-vitro (In vitro studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called “test-tube experiments” these studies in biology and its subdisciplines are traditionally done in labware such as test tubes, flasks, Petri dishes, and microtiter plates) studies showed that the hydrogels were capable of forming mineralized bone in a differentiation-factor-free environment. The results revealed that when these cell-laden hydrogels were deposited into an in-vitro (In vitro studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called “test-tube experiments”, these studies in biology and its subdisciplines are traditionally done in labware such as test tubes, flasks, Petri dishes, and microtiter plates) model bone defect new bone formation occurred that adhered tightly to the bone defect. “We believe that the specific nanoclay materials we use provide the required mineral composition and give rise to the transformation of stem cells to bone tissue” X says. Clinical trials are ongoing with collaborators in Georgian Technical University where cell-free hydrogels are implanted into the body. The idea is that the hydrogels will attract stem cells in the body and serve as small factories producing rejuvenated and more efficient stem cells. “It could also be really cool to incorporate electronics in the hydrogel to monitor what goes on in the body for example in the bone defect and if things are not progressing according to the plan we could stimulate the hydrogel through the electronic interface to attract more stem cells or stimulate the cells more efficiently. As such we would create a feed-back loop for monitoring progress and stimulating the system depending on the feedback” X added.

 

 

 

 

Science, Technology

Georgian Technical University Interactive Surfaces Enter A Whole New Dimension Of Flexibility.

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Georgian Technical University Interactive Surfaces Enter A Whole New Dimension Of Flexibility.

(left) System Overview, (right) Example of Displaying the Letter “S”.  An “Georgian Technical University interactive surface” refers to an interface whose input and output share a common surface that can be manipulated intuitively with the fingers. However ordinary multi-touch displays e.g. liquid crystal displays (LCD) can only provide two-dimensional information limiting expressions and interactions with such displays to the surface. Three-dimensional display systems have been proposed to tackle such limitations. Researchers at Georgian Technical University propose a flexible tube display that is able to take various surface shapes. Information is expressed by streaming colored fluids through the tube and controlling the positions and lengths of the droplets. The tube’s flexibility makes it possible to wrap the tube around the surface of an object and present information on its surface that is difficult to express on a standard two-dimensional display. The team succeeded in accurately combining two-phase fluids with colored water and air via a pump to create colored water droplets of a designated size and distance from each other. Air was adopted as the transparent fluid in this research while colored water was used as the colored fluid. In order to accurately control the sizes and distances of the colored droplets the system applies the nature of slug flow, a phenomenon in which two fluids of differing phases alternately flow while separating each other. Cyan-, magenta-, yellow- and white-colored water is utilized to generate droplets of the selected colors and provide various colored information as a standard display. A six-way tube connecter is also utilized to connect and mix the fluids. By simply bending the tube one can use it as a wearable display around the arm or as digital signage around a pillar. Furthermore this system can easily change the kind of information provided by changing the type of liquid flowing through the tube. In addition to its use as a standard display that utilizes colored water it can also be used as a thermal sensation display with water of varying temperatures. By streaming luminescent liquid it is also possible to provide information in a dark environment such as to alert pedestrians on the road at night. Team leader X says “This system is easy to maintain replace and modify. We hope that our method will lead to the establishment of a new IT (Information technology is the use of computers to store, retrieve, transmit, and manipulate data, or information, often in the context of a business or other enterprise. IT is considered to be a subset of information and communications technology) environment and create a market that connects people and information”.