Concepts In Science Technology YouTube Lecture Handouts

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Watch Video Lecture on YouTube: 20 Key GS Concepts in Science & Technology: Most Important "In News" Topic!

20 Key GS Concepts in Science & Technology: Most Important "In News" Topic!

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Science and Technology Key Concepts

Einstein Chwolson Ring

  • Gravity bends space

  • Light will follow curvature of space (similar to lens bending the light)

AMOLED Display

  • Active-matrix organic light-emitting diode

  • Used in mobile devices and televisions

  • OLED - thin-film-display technology - organic compounds

  • Low-power, low-cost and large-size applications

  • Generate light (luminescence) upon electrical activation that have been deposited or integrated onto a thin-film-transistor (TFT) array - series of switches to control the current flowing to each individual pixel

Light –Fidelity (LI-Fi)

  • Uses light waves rather RF to carry data

  • LED bulb functions as a router & is connected to the Internet

  • Unlicensed and free to use

  • High data speed due to low interference

  • Double benefit of access to light & internet

  • Doesn’t interfere with electronic circuitry

  • Works under water

  • Data density 1000 times of Wi-Fi

  • Internet data flows in via device into bulb & is carried by light waves

  • Light waves falls on dongle connected to the computer

Low Temperature Thermal Desalination (LTTD)

  • When there is difference in temperature at different sea levels

  • If pressure is less, water evaporates at less than its normal temperature

  • Surface temperature of sea water is warmer than deep sea water

  • Surface water is collected & vacuum is created over it to evaporate

  • When evaporated vapor passes over cold water it gets condensed & water is distilled

  • Less ecological and environmental cost


  • Find arrangement of atoms in the crystalline solids

  • 2012: UN recognized importance of science of crystallography

  • 2014: International Year of Crystallography

  • X-ray crystallography used to determine structure of large biomolecules such as proteins

  • Uses X-ray, neutron, and electron diffraction techniques to identify and characterize solid materials

Image of Crystallography

Image of Crystallography

Image of Crystallography


  • Spin transport electronics or spin electronics or Flextronics

  • Emerging technology uses intrinsic electron spin and associated magnetic moment along with fundamental electronic charge

  • Spins are manipulated by magnetic & electrical fields


  • High Efficiency Video Coding

  • Video compression standard

  • Successor to H.264/MPEG-4 AVC (Advanced Video Coding)

  • First version completed and published in early 2013

  • Second version completed and published in 2014

  • 2nd version - supporting enhanced video formats, scalable coding extensions, and multi-view extensions

Micro Plastics

  • Small plastic particles in the environment

  • Smaller than 1 mm or 5 mm

  • Common use of 333 μm mesh neuston nets for field sampling (sample water volume).

  • However, scientifically, their integral impact on wildlife and human health is not well established.

Doppler Radar

  • In News: 6th Doppler radar on East Coast

  • Other locations on East Coast: Chennai, Kolkata, Machilipatanam, Visakhapatnam and Paradip

  • Eastern coast prone to cyclones & will boost weather forecasting system

  • Built by ISRO and BHEL

  • Doppler Principle: When source for signals and observer are in relative motion - change in frequency (wavelength) is observed by observer

  • When source and observer move closer, frequency increases


  • Eco-friendly batteries

  • Generate electricity by renewable source like Sugar, glucose etc.

  • Final products are not a waste

  • Non-flammable and non-toxic

  • Ability to instant recharge and long backup

Image of Mechanism of Bio Battery

Image of Mechanism of Bio Battery

Image of Mechanism of Bio Battery

NPL Syncs Leap Second with Indian Time

  • National Physical Laboratory added leap second

  • To compensate slowdown of earth’s rotation

  • Every day 2000th of second is less

  • Every 500 days, 1 second is added to international atomic time

  • If clocks not updated it can led to failure of military systems, aircraft collision and error in financial markets

Ferroelectric Liquid Crystal Device (FLCD)

  • New generation display device like LCD

  • Has Ferro dielectric liquid crystal – with electricity gets magnetized

  • Fast switching time

  • Low dot pitch which results in a high resolution

  • Greater viewing angle

  • Better picture and thinner interface

  • Cheaper to run on electricity


  • Uses properties of quantum dots to localize magnetic or electrical fields at very small scales

  • Used in high-density in formation storage, energy storage & LED

  • Magnetic nan odots for future information storage

  • Store over 100 times more data than today’s hard drives

  • Tiny magnets which can switch polarity to represent a binary digit

Double Fertilization

  • In flowering plants (angiosperms)

  • Female gametophyte (mega gametophyte or embryo sac) joins with two male gametes (sperm)

Image of Double Fertilization

Image of Double Fertilization

Image of Double Fertilization

Genome Sequencing

  • Laboratory process that determines complete DNA sequence of an organism's genome at a single time

  • Sequence organism's chromosomal DNA & DNA in mitochondria

Noise Net

  • Controlled air around aircraft is filled with acoustic noise

  • Makes area near aircraft much riskier for birds

  • Reduce number of birds near aircrafts by 80%

  • Saves birds from collision


  • Genome editing tool

  • Faster, cheaper and more accurate

  • Simplest, versatile & most precise

  • 2 molecules that change into DNA

  • Enzyme Cas9 - pair of ‘molecular scissors’ - cut 2 strands of DNA at a specific location

  • guide RNA (gRNA): RNA sequence within longer RNA scaffold. Scaffold binds and ‘guides’ Cas9 to the right part of the genome

Mutation caused by the repair

Enzyme Cas9- Mutation

Mutation caused by the repair


  • High-voltage direct current (HVDC)

  • Electric power transmission system

  • Power super highway & electrical super highway

  • Uses direct current (DC)

  • Less expensive & lower electrical losses

Image of HVDC

Image of HVDC

Image of HVDC

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