full transcript

From the Ted Talk by Max G. Levy: How do bulletproof vests work?

Unscramble the Blue Letters


Named Kevlar, this alternating blend of 1,4-phenylene-diamine and tehlhatyeorpl crldiohe combine at the molecular level to form a series of plelaarl chains. At rest, these chains aigln in strict rows, giving the polymer order and crystalline strength. But when pressure is applied, the chains wigglre around, allowing the material to flow like a liquid. This so-called liquid crystal polymer was unprecedented, and when Kwolek’s team spun the viscous fluid into a fiber, the rsultes were better than they could have heopd. Not only were the fibers flexible and resistant to heat, acid, and various chemicals, when woven together, they were also stronger than setel.

Open Cloze


Named Kevlar, this alternating blend of 1,4-phenylene-diamine and _____________ ________ combine at the molecular level to form a series of ________ chains. At rest, these chains _____ in strict rows, giving the polymer order and crystalline strength. But when pressure is applied, the chains _______ around, allowing the material to flow like a liquid. This so-called liquid crystal polymer was unprecedented, and when Kwolek’s team spun the viscous fluid into a fiber, the _______ were better than they could have _____. Not only were the fibers flexible and resistant to heat, acid, and various chemicals, when woven together, they were also stronger than _____.

Solution


  1. hoped
  2. results
  3. parallel
  4. chloride
  5. steel
  6. wriggle
  7. align
  8. terephthaloyl

Original Text


Named Kevlar, this alternating blend of 1,4-phenylene-diamine and terephthaloyl chloride combine at the molecular level to form a series of parallel chains. At rest, these chains align in strict rows, giving the polymer order and crystalline strength. But when pressure is applied, the chains wriggle around, allowing the material to flow like a liquid. This so-called liquid crystal polymer was unprecedented, and when Kwolek’s team spun the viscous fluid into a fiber, the results were better than they could have hoped. Not only were the fibers flexible and resistant to heat, acid, and various chemicals, when woven together, they were also stronger than steel.

Frequently Occurring Word Combinations


ngrams of length 2

collocation frequency
atomic bonds 3
liquid crystal 2
bullet hits 2
hydrogen bonds 2


Important Words


  1. acid
  2. align
  3. allowing
  4. alternating
  5. applied
  6. blend
  7. chains
  8. chemicals
  9. chloride
  10. combine
  11. crystal
  12. crystalline
  13. fiber
  14. fibers
  15. flexible
  16. flow
  17. fluid
  18. form
  19. giving
  20. heat
  21. hoped
  22. kevlar
  23. level
  24. liquid
  25. material
  26. molecular
  27. named
  28. order
  29. parallel
  30. polymer
  31. pressure
  32. resistant
  33. rest
  34. results
  35. rows
  36. series
  37. spun
  38. steel
  39. strength
  40. strict
  41. stronger
  42. team
  43. terephthaloyl
  44. unprecedented
  45. viscous
  46. woven
  47. wriggle