Science & Technology (Part - 2) - Current Affair, March 2018 - Current Affairs

6.5. GSAT-6A

Why in news
Recently, GSAT-6A was launched on board the GSLV F08, from the Satish Dhawan Space Centre at Sriharikota.

Highlight

• Launch marked the 12th flight of Geosynchronous Satellite Launch Vehicle GSLVF08 and sixth flight with the indigenous Cryogenic upper stage.
• GSAT-6A, similar to GSAT-6, is a high-powered Sband communication satellite which would help improve mobile communications to handheld devices, as well as network management techniques useful in satellite- based mobile communication applications.
• However, ISRO lost contact with its communication satellite GSAT-6A.

6.6. COPERNICUS PROGRAMME

Why in News?
India and the European Union recently signed an agreement that will enable them to share earth observation data from each other's satellite.

About the Arrangement
• Copernicus Programme is Earth observation programme headed by the European Commission (EC) in partnership with the European Space Agency (ESA).
• India will get free, full and open access to the data from the Copernicus Sentinel family of six satellites.
• Reciprocally India will provide free, full and open access to the data from ISRO’s land, ocean and atmospheric series of civilian satellites (Oceansat-2, Megha-Tropiques, Scatsat-1, SARAL, INSAT-3D, INSAT3DR) with the exception of commercial high-resolution satellites data.
• The services address six thematic areas: land, marine, atmosphere, climate change, emergency management, and security.

6.7. AIR-BREATHING ELECTRIC THRUSTER

Why in news?
Recently European Space Agency (ESA) fired world’s first ever air-breathing electric thruster which could keep satellites in low orbit for longer time.

What is Air-Breathing Electric Thruster or Ion Thruster?
• It is an ion thruster which uses Air Breathing Electric Propulsion (ABEP) or RAM electric propulsion method.

How does ABEP works?
• ABEP sucks in air molecules from top of the atmosphere instead of using on-board propellant.
• Then it gives these molecules an electric charge and accelerates them.
• Finally, it ejects the ionized molecules back into space which causes thrust.

Significance of ABEP
• The new system is very significant as it reduces the weight of the satellite, thus reducing the consumption of fuel.
• It extends the stay of satellites in space to almost indefinite time and also opens the doors for deep space exploration.

6.8. MICRO-LED: THE NEXT-GEN DISPLAY TECHNOLOGY

Why in news?
Samsung recently demonstrated a prototype MicroLED based TV of 146 inches display.

About MicroLED
• It is an emerging flat panel display technology in which displays consist of arrays of microscopic LEDs forming the individual pixel elements.
• These are simply traditional LEDs shrunk down and placed into an array. The LED technology is not new but manufacturing a panel array using such tiny components is very difficult and currently not commercially viable over OLED.

OLEDs and MicroLEDs
• OLEDs are self-emissive, which means they requires no backlight; instead, it lights each individual pixel as needed. Like OLED, Micro LED too don't need backlight.
• OLEDs are made of organic materials that age, resulting in a decrease in luminance over time, with the potential for uneven ageing. MicroLEDs being inorganic (gallium nitride) are not as susceptible to ageing.
• This switch from organic to inorganic also reduces the need for a polarizing and encapsulation layer, making panels thinner.
• The OLED manufacturing process also limits the possible screen shapes and sizes. The MicroLED technology are “modular” in nature which are flexible to configure any size.
• MicroLEDs are more power-efficient than OLEDs.

6.9. COLD FUSION REACTOR

Why in News?
India is taking steps to start research into Cold Fusion Reactor.

Cold Fusion Reactor
• Cold Fusion Reaction or Low Energy Nuclear Reaction (LENR) technology is nuclear fusion supposedly occurring at or close to room temperature and is still in research phase.
• It is a form of energy generated when hydrogen interacts with various metals like nickel and palladium.
• Cold fusion seeks to produce nuclear energy without harmful radiation, complex equipment and the application of very high temperatures and pressures.

Potential Benefits

• LENR technology could be used to build vehicular and at-home nuclear reactors that provide both heat and electricity.
• Radioactive materials can be transmuted to benign elements, promising a path to ridding the planet of thousands of tons of radioactive waste.
• Ultra-clean and Energy Dense: Cold fusion energy generators will not need to be connected to an electrical grid. Small and portable power units will provide energy on-demand in any location.

6.10. NOVEL MATERIAL TO CONVERT WASTE HEAT TO ELECTRICITY

Why in news?
Recently, a team of researchers from Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) have developed a novel material.

About Silver Copper Telluride (AgCuTe)
• It is a thermoelectric material which can be used for converting waste heat into electricity as it exhibits poor conductivity in 25-425 degree C range but shows good electrical conductivity.
• Silver, Copper and Tellurium in the material have different properties which have resulted in successful experiment.
• Properties –

o Tellurium: Its atoms are strongly bound and the lattice is very rigid which provides a conduction channel for holes thus rendering good electrical conductivity to the compound.
o Silver and Copper: contribute to low thermal conductivity. Over 170-degree C, both silver and copper ions flow like liquid within the rigid tellurium sublattice, thereby reducing the thermal conductivity to the level of glass without affecting the hole (electrical carrier) transport.

• Significance:
o AgCuTe has the efficiency of 14% to convert heat into electricity which can be used to avoid loss of about 65% of the utilized energy which is wasted as heat.
o The development of AgCuTe could be very helpful for automobile industry, chemical and thermal power plants, steel plants, waste to energy plants etc.

6.11. VATERITE - RARE MINERALS IN PLANTS

Why in News?
• Vaterite, a rare and unstable mineral, was found on the leaves of a number of alpine plants. This is the firsttime rare minerals have been found to be associated with the plants.

About Vaterite
• Vaterite is a mineral, a polymorph (a solid chemical compound that exists in more than one crystalline form) of calcium carbonate (CaCO3).
• Being unstable in Earth’s humid atmosphere, it often reverts to more common forms of calcium carbonate, such as calcite.
• Vaterite is often associated with outer space and on earth it is found in some sea and freshwater crustaceans, bird eggs, the inner ears of salmon, meteorites and rocks.
• Its special properties make it a potentially superior carrier for medications due to its high loading capacity, high uptake by cells and its solubility properties that enable it to deliver a sustained and targeted release of therapeutic medicines to patients.