light penetration depth
31V838 Monocerotis — and its light echo as imaged by the Hubble Space Telescope on December 17, 2002. Credit: NASA/ESA Observation data Epoch 2000.0& …
32Muon spin spectroscopy — is an experimental technique based on the implantation of spin polarized muons in matter and on the detection of the influence of the atomic, molecular or crystalline surroundings on their spin motion. The motion of the muon spin is due to the… …
33inland water ecosystem — ▪ biology Introduction complex of living organisms in free water on continental landmasses. Inland waters represent parts of the biosphere within which marked biological diversity, complex biogeochemical pathways, and an array of… …
34Laser-hybrid welding — is a type of welding process that combines the principles of laser beam welding and arc welding. Introduction The combination of laser light and an electrical arc into an amalgamated welding process has beenknown since the 1970 s, but has only… …
35Deep sea mining — is a relatively new mineral retrieval process that takes place on the ocean floor. Ocean mining sites are usually around large areas of polymetallic nodules or active and extinct hydrothermal vents at about 1,400 3,700 meters below the ocean’s… …
36Niobium — zirconium ← niobium → molybdenum V ↑ Nb ↓ Ta …
37Technetium — molybdenum ← technetium → ruthenium Mn ↑ Tc ↓ Re …
38Virginia Tech massacre — People gather to mourn after the shooting. Location Blacksburg, Virginia, United States …
39Comet Shoemaker–Levy 9 — D/1993 F2 (Shoemaker–Levy) Image of Comet Shoemaker–Levy 9 fragments (total: 21), taken on May 17, 1994 Discovery Discovered by: Carolyn Shoemaker Eugene M. Shoemaker David Levy Discovery date …
40Quantum chromodynamics — Standard model of particle physics Standard Model …
