Press Information Bureau - Science and Technology (May 2020)
Press Information Bureau - Science and Technology (April 2020)
Plasmonic Semiconductor Nanomaterials
- PSN are metal-like materials with free electrons on the surface that oscillate collectively when hit by light.
- It uses solar light to increase the photocatalytic efficiency to degrade pollutants as well as generate renewable Hydrogen.
- These materials can easily adsorb toxic ions like arsenic and fluoride, which are often found in water in North East India and convert it to its not toxic forms when they are exposed to sunlight.
- PSN can be used for hydrogen energy generation, a process which has shown high photon to hydrogen conversion efficiency under visible and near infra-red light.
What are Semiconductors?
- Semiconductors are materials which have a conductivity between conductors (generally metals) and non-conductors or insulators (such as most ceramics).
- Its resistance falls as its temperature rises; metals are the opposite.
- They can be pure elements, such as silicon or germanium, or compounds such as gallium arsenide or cadmium selenide.
What are Nanomaterials?
- Nanomaterials are materials of which a single unit small-sized (in at least one dimension) between 1 and 100 nm (the usual definition of nanoscale).
- Materials with structure at the nanoscale often have unique optical, electronic, or mechanical properties.
- They are created from the gas phase by producing a vapour of the product material using chemical or physical means.
- Examples of nanomaterials include carbon nanotube, nanoparticles, metal rubber, quantum dots, nanopores and many more.
Chitra Acrylosorb Secretion Solidification System
- Scientists at Sree Chitra Tirunal Institute for Medical Sciences and Technology (SCTIMST) have designed and developed a highly efficient superabsorbent material for liquid respiratory and other body fluid solidification and disinfection for the safe management of infected respiratory secretions.
- It is a highly efficient superabsorbent material for liquid respiratory and other body fluid solidification and disinfection.
- AcryloSorb can absorb liquids at least 20 times more than its dry weight and also contains a decontaminant for in situ disinfection.
- Containers filled with this material will immobilize the contaminated fluid by solidifying it (gel-like), thus avoiding spillage and will also disinfect it.
- The canister containing the solidified waste canister can then be decomposed as all other biomedical waste by incineration.
How it works?
- In the developed system, suction canisters, disposable spit bags have been designed with “AcryloSorb” technology.
- They are lined inside with the AcryloSorb material.
- The AcryloSorb suction canisters will collect the liquid respiratory secretions from ICU patients or those with copious secretions treated in the wards.
- The container will be spill-proof and can be sealed after use, making it safe and fit for disposal through the usual incineration system for biomedical wastes.
Significance of Acrylosorb:
- Sealable and disposable spit bags can be provided for solidifying the sputum and saliva of ambulant patients with respiratory infections, which can then be incinerated.
- Thus, it reduces the risk for the hospital staff, the need for personnel for disinfecting and cleaning the bottles and canisters for reusing them and makes the disposal safer and easier.
Coupled Lithosphere-Atmosphere- Ionosphere-Magnetosphere System
- Scientists of Indian Institute of Geomagnetism (IIG) an autonomous institution of the DST has extensively studied the signatures of recent large earthquakes into the ionosphere with an ambitious aim to derive the seismic source characteristics from the ionosphere.
- The research is a part of the interdisciplinary program ‘Coupled Lithosphere-Atmosphere- Ionosphere-Magnetosphere System’ (CLAIMS) of IIG.
- CLAIMS focus on energy transfer to the atmosphere during solid Earth processes such as earthquakes as well as tsunamis.
- Key terms: Co-seismic Ionospheric Perturbations (CIP)
- In general, the Earth crust uplift during an earthquake produces compressional (i.e. pressure) waves in the overlying atmosphere.
- These waves propagate upward in the region of exponentially decreasing atmospheric neutral density, and thus, wave amplitude increase with atmospheric heights.
- On arrival at ionospheric heights, the waves redistribute ionospheric electron density and produce electron density perturbations (disruption) known as CIP.
Objective of CLAIMS:
- The spatial distribution of near field co-seismic Ionospheric perturbations (CIP) associated with this event could reflect well the ground deformation pattern evolved around the epicentre.
- These CIPs were derived using the Global Positioning System (GPS) measured Total Electron Content (TEC).
- The CIP distribution was estimated at Ionospheric piercing point (IPP)
- Other factors affecting CIP
The major effective non-tectonic forcing mechanisms at ionospheric altitudes are the –
- orientation between the ambient geomagnetic field and seismic induced neutral wave perturbations.
- orientation between the moving satellite line of sights and the wave perturbations.
- ambient ionospheric electron density gradient.
- The ionosphere is the ionized part of Earth’s upper atmosphere, from about 60 km to 1,000 km altitude.
- It is a region that includes the thermosphere and parts of the mesosphere and exosphere.
- It is ionized by solar radiation.
- IIT, Gandhinagar has launched Project Isaac to engage its students in creative projects to enhance their critical skills while they are confined to their homes because of Coronavirus.
- The project is inspired by Sir Isaac Newton, who was similarly sent home by Trinity College, Cambridge, because of the Great Plague of London in 1665.
- During this year, Newton, then a 22-year-old college student developed some of his most profound discoveries, including early calculus, as well as his theories of optics and gravity.
- As part of the project, four different competitions are being organized by IIT, Gandhinagar to cultivate new skills among students regarding writing, painting, coding, music, creative expression, and so on.
- Students can take part in competitions online.
Laser Surface Micro-texturing
Laser surface micro-texturing:
- International Advanced Centre for Powder Metallurgy & New Materials (ARCI) an autonomous R&D Centre of of Science and Technology has developed ultrafast laser surface texturing technology, which can improve the fuel efficiency of internal combustion engines.
- This technology offers precise control of the size, shape and density of micro-surface texture features. This has gained momentum as a way to control friction and wear.
- In this technology, a pulsating laser beam creates micro-dimples or grooves on the surface of materials in a very controlled manner.
- Such textures can trap wear debris when operating under dry sliding conditions and sometimes provide effects like enhancing oil supply (lubricant reservoir) which can lower friction coefficients and may enable reduced wear rate.
- The texture surfaces were created on automotive internal combustion engine components, piston rings and cylinder liners using 100 fs pulse duration laser.
- The micro dimples of 10-20 μm diameter and about 5-10 μm deep which have been created with laser beams had a regular pattern.
Benefits of micro-texturing:
- The created textures were tested in an engine test rig under different speeds and temperatures of coolant and lubrication oil, and it was observed that there was a 16% reduction in the lube oil consumption with the use of texture on the piston rings.
- The 10-hour lube oil consumption test shows that the blowby substantially reduced with textured rings.
- Fabrication of a pattern of micro dimples or grooves on the surface of materials results in a change in surface topography which generates additional hydrodynamic pressure, thereby increasing the load-carrying capacity of the surfaces.
- Hence these become useful for trapping wear debris when operating under dry sliding conditions and sometimes provide effects like enhancing oil supply (lubricant reservoir) which can lower friction coefficients and may enable reduced wear rate.
Friction-reducing Nanocomposite Coatings
What are Nanocomposites?
- A group of scientists at the International Advanced Research Centre for Powder Metallurgy & New Materials (ARCI) have developed a process for size-selective deposition of nanocomposite coatings which can reduce friction of these dynamic systems.
- Nanocomposite coatings are formed by mixing two or more dissimilar materials at nanoscale to improve the physical, chemical and physicochemical properties of the new materials.
- The scientists have found that nickel tungsten-based coatings with infusion of particular sized Silicon Carbide (SiC) submicron particles using a pulsed electroplating can provide an excellent combination of wear and corrosion resistance.
- Many aerospace, defence, automobile, space devices need to reduce friction, wear, and tear to enhance the life of components.
- Lubricating these dynamic systems add to the cost, complexity, and weight of these systems.
- The coating could help in reducing the friction of such devices.
Potential Fishing Zone (PFZ) Advisories
Potential Fishing Zone (PFZ):
- The Indian National Centre for Ocean Information Services (INCOIS), Hyderabad has reported that Oceansat Satellite data from ISRO are used to prepare the PFZ advisories on the potential rich fishing areas and provide to the sea faring fishermen in all states.
- This is the first advisory service started by INCOIS. The backbone of this service is the real-time data for Oceancolor and SST provided by the OCEANSAT and NOAA
- This service was started because there was a need to identify the potential fishing zones to help the fishermen to get better catch while they were at the sea.
- This service was started by the Ministry of Earth Sciences with the help of the Department of Space and several institutions under the Ministry of Agriculture.
How it works?
- This service makes use of parameters such as sea surface temperature and chlorophyll content provided by NOAA-AVHRR and Oceancolor satellites.
- Features such as oceanic fronts, Meandering Patterns, Eddies, Rings, Up Welling areas etc. are identified sites for fish accumulation.
- These features can easily be identified from Sea Surface Temperature and Chlorophyll data.
- The availability of Chlorophyll from OCEANSAT and MOdDIS has further enriched these advisories in the recent years.
- Hence, PFZ advisories have helped the fishing community to locate the fishing zones with accuracy.
Special advisories for fisherman:
- Another feature of PFZ service is the generation of species-specific advisory to enable the fishermen folk to distinguish between the exploited and under-exploited species in the potential fishing zones.
- This enables them to have sustainable fishery management by targeting only the under-exploited species in the fishing zones.
- This approach enables them to avoid fishing the over-exploited species over and over again.
ARI-516 Grape Variety
- Pune’s Agharkar Research Institute (ARI), an autonomous institute of the DST has developed a hybrid variety of grapes which is resistant to fungal diseases, high yielding and has excellent juice quality.
- The hybrid variety ARI-516 has been developed by interbreeding of two species from the same genus — Catawba variety of Vitis labrusca and Beauty seedless variety of Vitis vinifera.
- It is a result of collaboration between Maharashtra Association for the Cultivation of Science (MACS) and ARCI and can benefit farmers, the processing industry and consumers.
- This variety of grapes is resistant to fungal diseases, high yielding and has excellent juice quality.
- The fungal resistance of ARI-516 has been derived from Catawba, which is an American grape variety.
- It is also suitable for preparation of juice, raisin, jam and red wine and farmers are enthusiastically adopting the variety.
- It has superior quality fruits and higher yield per unit area.
- An early ripening hybrid, it matures in 110 – 120 days after pruning.
- Being moderately resistant to a majority of fungal diseases, its cost of production is lower.
Grape production in India:
- India ranks twelfth in the world in terms of grape production.
- About 78% of grape production in India is utilized for consumption, 17-20 % for raisin production, 1.5 % for wine and 0.5 % for juice.
- Maharashtra leads in the production of grapes in India with a share of 81.22 %. A negligible share of grapes is used for juice production.
- A majority of farmers in Maharashtra cultivate ‘Thompson seedless’ and its clones for table purpose or raisin making.
Quantum coin or ‘Qubit’ and Entanglement Theory
- Researchers from Raman Research Institute (RRI), an autonomous institution under the of Science & Technology, have devised a new test for fairness of quantum coin or ‘qubit’ using entanglement theory.
- The Qubit is the basic unit of information in a quantum computer.
- It is a special type of correlation that exists in the quantum world with no classical counterpart.
- The researchers from RRI made use of this quantum resource to arrive at a test for fairness of a quantum coin (a qubit).
- Their strategy, which makes use of entanglement, enables better discrimination between quantum states. Such advantage is valuable in quantum sensors.
- This work is a significant contribution to the domain of quantum state discrimination, which is an essential aspect of quantum information science.
- It brings out the crucial role of entanglement in improving our ability to discriminate quantum states.
- In this work the researchers concretely implemented the theoretical idea on the simulation facility of the IBM quantum computer.
- By repeated trials, one can determine the fairness of a classical coin with a confidence which grows with the number of trials.
- A quantum coin can be in a superposition of heads and tails.
- Given a string of qubits representing a series of trials, one can measure them individually and determine the state with a certain confidence.
- The team has shown that there is an improved strategy which measures the qubits after entangling them, which leads to a greater confidence.
- This is a significant contribution to quantum state discrimination, an essential aspect of quantum information science which is expected to influence quantum sensing.
- The domain of Quantum Information and Quantum Computing Technology is a growing area of research which is expected to influence Data Processing, which in turn, plays a central role in our lives in this Information Age.
- For instance, bank transactions, online shopping and so on crucially depend on the efficiency of information transfer.
- Thus, the recent work on quantum state discrimination is expected to be valuable in people’s lives in the current era.
Polymer Electrolyte Membrane Fuel Cells (PEMFC)
Polymer Electrolyte Membrane Fuel Cells:
- Scientists at International Advanced Research for Powder Metallurgy & New Materials (ARCI), Hyderabad have developed Polymer Electrolyte Membrane fuel cells (PEMFC).
- Proton-exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells are a type of fuel cell being developed mainly for transport applications, as well as for stationary fuel-cell applications and portable fuel-cell applications.
- Their distinguishing features include lower temperature/pressure ranges (50 to 100°C) and a special proton-conducting polymer electrolyte membrane.
- PEMFCs generate electricity and operate on the opposite principle to PEM electrolysis, which consumes electricity.
- They are a leading candidate to replace the aging alkaline fuel-cell technology, which was used in the Space Shuttle.
- The PEMFC uses a water-based, acidic polymer membrane as its electrolyte, with platinum-based electrodes.
- The protons pass through the membrane to the cathode side of the cell while the electrons travel in an external circuit, generating the electrical output of the cell.
Applications in disaster management:
- Emergency Operation Centres (EOC) backed with 10 kW systems is being planned as a natural disaster management measure.
- Tamil Nadu is generally affected by five to six cyclones every year, of which two to three are severe and is followed by frequent power cuts.
- ARCI is now planning to set up a PEMFC system for Tamil Nadu to operate the systems like early warning systems, VHF set, IP phone, BSNL Ethernet and office equipment like scanner, computers, printers, phone, FAX and normal requirements like lighting and fan.
CHITRA Flow Diverter Stent
What are Aneurysms?
- The Sree Chitra Tirunal Institute of Medical Sciences and Technology, Thiruvananthapuram an Institute of National Importance under the Department of Science and Technology has developed an innovative intra-cranial flow diverter stent for the treatment of aneurysms of the blood vessels of the brain.
- Intra-cranial aneurysm is a localized ballooning, bulging or dilation of arteries in the brain caused by progressive weakening of the inner muscles of the wall of the blood vessels.
- Spontaneous rupture of the aneurysm can result in bleeding into the space around the brain resulting condition called a Subarachnoid Haemorrhage (SAH) which can lead to paralysis, coma or death.
- Most often a ruptured brain aneurysm occurs in the space between the brain and the thin tissues covering the brain.
How to avert risks of Brain Aneurysms?
- Flow diverters stents when deployed in the artery in the brain bearing the aneurysms, diverts blood flow away from the aneurysm.
- This reduces the chances of its rupture from the pressure of blood flow.
- The Surgical treatment of an aneurysm involves opening the skull and a clip on the neck of aneurysm, so that it is cut off from the path of blood flow.
- There are three non-surgical, minimally invasive endovascular treatments of aneurysms of the brain.
- In two of these procedures, the aneurismal sacis filled with platinum coils or occluded using high viscosity liquid polymer which solidifies when released into the sac thus sealing the sac.
- All these techniques have some limitation or the other.
Why are flow diverter stent preferable?
- A more attractive third minimally invasive option is deploying a flow diverter stent to bypass the segment of the blood vessel which has the aneurysm.
- Flow diverters have the advantages of being flexible and adaptable to the shape and course of the vessel.
- Also flow diverters promote healing of the vessel wall by removing the constant stress of blood flow on it.
What is CHITRA flow diverter?
- The Chitra flow diverter is designed to have better grip on the walls of arteries of complex shapes in order to reduce the risk of migration of the device.
- The unique design is in its weave also makes this stent resistant to kinking or twisting, when it is placed in tortuous arteries and those with complex shapes. Even a 180 degrees bend does not occlude the lumen of the stent.
- Portion of the wires is made radio opaque for better visibility in X –Rays and fluoroscopy thus aiding accurate delivery of the diverter in the blood vessel.
- Nitinol, a super elastic alloy with shape memory was acquired from National Aero-space Laboratories, Bengaluru (CSIR-NAL).
- When the device is deployed at the site, it is released from its crimped locked position and assumes the desired and originally designed shape because of the shape memory property of Nitinol.
Benefits of CHITRA:
- The imported Flow diverter stents costs Rs 7-8 lakhs and is not manufactured in India.
- With the availability of the indigenous CHITRA, a well-established industry would be able to manufacture and sell at a much lower price.