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Honoring Copernicus - Three New Elements Added To The Periodic Table - 0 views

  • November 4, 2011, the General Assembly of the International Union of Pure and Applied Physics (IUPAP) is meeting at the Institute of Physics in London, to approve the names of three new elements
  • Element 110, darmstadtium (Ds),
  • Element 112. copernicium (Cn).
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  • Element111, roentgenium (Rg)
  • Are these new elements? Probably not.
  • As a general rule, these “new elements” are given names by their discoverer – which also leads to international debate
  • elements can be named after a mythological concept, a mineral, a place or a country, a property or a very known scientist… even an astronomer
  • element 112, this extremely radioactive synthetic element can only be created in a laboratory
  • Copernicium was created on February 9, 1996 by the Gesellschaft für Schwerionenforschung
  • its original name – ununbium – didn’t get changed until almost two years ago when a German team of scientists provided enough information to prove its existence
  • the rules were that it had to end in “ium” and it couldn’t be named for a living person.
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Chemistry's Biggest Loser: Official Atomic Weights Change For 19 Elements | Popular Sci... - 0 views

  • Improved measurements of different elements and their isotopes have changed the official atomic weights of 19 elements
  • The changes are relatively small, and they're part of a regular effort to update atomic weights
  • Every atom of an element
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  • silver as an example
  • has the same number of protons
  • Silver has 47
  • not every atom of an element necessarily has the same number of neutrons
  • different versions of an element's atoms are called isotopes
  • Silver occurs as silver-109 and silver-107
  • Chemists calculate the atomic weight of an element that you see on the periodic table from the masses of its isotopes, giving more common isotopes more weight than less common isotopes
  • doesn't necessarily mean every sample of silver on Earth has an atomic weight of exactly
  • samples of elements vary from place to place
  • erences play an important role in many sciences
  • They help chemists trace the origin of different materials
  • and date archaeological findings
  • The latest atomic weights measurements differ too little from their predecessors to really change science
  • do it?"
  • If it's just small changes, why
  • should give the best numbers there are
  • some new idea will come up that needs more accurate data
  • Molybdenum, Losing 0.0122
  • Atomic weights are relative, so they don't have units
  • Thorium, Losing 0.000322
  • Yttrium and Niobium, Tied, Losing 0.00001
  • Selenium, Gaining 0.0088
  • Cadmium, Gaining 0.0026
  • Holmium, Thulium and Praseodymium, All Tied, Gaining 0.00001
  • The changes in weights mostly come from continuing improvements in atomic mass measurements
  • advances in the technology behind mass spectrometers
  • not all about measuring more accurately
  • thorium, the IUPAC decided to recognize an isotope, thorium-230, that it previously thought was too rare to include in atomic weight calculations
  • The last time international chemistry
  • really altered the periodic table was in 2009, when IUPAC decided to list the atomic weights of some elements as ranges, instead of single numbers
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Unprecedented Maya Mural Found, Contradicts 2012 "Doomsday" Myth - 0 views

  • last known largely unexcavated Maya megacity, archaeologists have uncovered the only known mural adorning an ancient Maya house
  • still vibrant scene of a king and his retinue
  • walls are rife with calculations that helped ancient scribes track vast amounts of time
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  • markings suggest dates thousands of years in the future
  • Perhaps most important, the otherwise humble chamber offers a rare glimpse into the inner workings of Maya society
  • in today's Xultún
  • just 6 square miles (16 square kilometers) of jungle floor—it's a wonder Saturno's team found the artwork at all
  • At the Guatemalan site in 2010 the Boston University archaeologist and Ph.D. student Franco Rossi were inspecting a looters' tunnel, where an undergraduate student had noticed the faintest traces of paint on a thin stucco wall.
  • began cleaning off 1,200-year-old mud and suddenly a little more red paint appeared.
  • What the team found, after a full excavation in 2011, is likely the ancient workroom of a Maya scribe, a record-keeper of Xultún.
  • this was a workspace. People were seated on this bench" painting books that have long since disintegrated
  • The books would have been filled with elaborate calculations intended to predict the city's fortunes. The numbers on the wall were "fixed tabulations that they can then refer to—tables more or less like those in the back of your chemistry book," he added.
  • Undoubtedly this type of room exists at every Maya site in the Late Classic [period] and probably earlier, but it's our only example thus far."
  • Maya civilization spanned much of what are now Guatemala, Belize, and Mexico's Yucatán region. Around A.D. 900 the Classic Maya centers, including Xultún, collapsed after a series of droughts and perhaps political conflicts
  • The apparent desperation of those final years may have played out on the walls of the newly revealed room—the only major excavation so far in Xultún.
  • Despite past looting, the interior of the newfound room is nearly perfectly preserved.
  • Among the artworks on the three intact walls is a detailed orange painting of a man wearing white disks on his head and chest—likely the scribe himself
  • the researchers noticed several barely visible hieroglyphic texts, painted and etched along the east and north walls of the room
  • One is a lunar table, and the other is a "ring number"—something previously known only from much later Maya books, where it was used as part of a backward calculation in establishing a base date for planetary cycles
  • Nearby is a sequence of numbered intervals corresponding to key calendrical and planetary cycles.
  • The calculations include dates some 7,000 years in the future
  • The Maya at Xultún were likely less concerned with the end of the world than the end of their world
  • Sadly, we may never understand the full context of the workroom. Many of the glyphs are badly faded. Worse, the entire city of Xultún was looted clean during the 70s, leaving very little other writing or antiquities.
  • Because of this, and despite Xultún's obvious prominence in the Maya world, many archaeologists had written off the
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Mars Rover Curiosity Has First Big Malfunction - 0 views

  • hoped Curiosity would resume science work in about a week.
  • similar problems were caused by high-energy solar and cosmic ray strikes
  • On other space missions
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  • Curiosity has protections against such high-energy disruptions, but the problem was compounded by what appears to have been the location of the strike—in the directory, or "table of contents," of the computer's memory
  • appears to have caused the computer to get stuck in an endless loop.
  • previous rovers experienced many so-called "anomalies" during the early part of their treks
  • Even if the rover is fully operational again in a week, the amount of science it can perform is limited.
  • the sun comes between Mars and the Earth in early April, partially blocking the path for radio commands for an entire month
  • The Curiosity team had planned to send back science data from Mars during that period—called "solar conjunction"—but had decided not to send up any commands.
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Another tiny miracle: Graphene oxide soaks up radioactive waste - 0 views

  • Graphene oxide has a remarkable ability to quickly remove radioactive material from contaminated water
  • A collaborative effort by the Rice lab of chemist James Tour and the Moscow lab of chemist Stepan Kalmykov
  • microscopic, atom-thick flakes of graphene oxide bind quickly to natural and human-made radionuclides and condense them into solids
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  • flakes are soluble in liquids and easily produced in bulk
  • The discovery
  • could be a boon in the cleanup of contaminated sites like the Fukushima nuclear plants
  • could also cut the cost of hydraulic fracturing ("fracking") for oil and gas recovery and help reboot American mining of rare earth metals
  • Graphene oxide's large surface area defines its capacity to adsorb toxins
  • high retention properties are not surprising
  • What is astonishing is the very fast kinetics of sorption, which is key
  • the collaboration took root when
  • a graduate student
  • graduate student in Kalmykov's group, met at a conference several years ago.
  • researchers focused on removing radioactive isotopes of the actinides and lanthanides – the 30 rare earth elements in the periodic table – from liquids, rather than solids or gases
  • Naturally occurring radionuclides are also unwelcome in fracking fluids that bring them to the surface in drilling operations
  • When groundwater comes out of a well and it's radioactive above a certain level, they can't put it back into the ground
  • Companies have to ship contaminated water to repository sites around the country at very large expense
  • The ability to quickly filter out contaminants on-site would save a great deal of money
  • even greater potential benefits for the mining industry
  • Environmental requirements have "essentially shut down U.S. mining of rare earth metals, which are needed for cell phones
  • China owns the market because they're not subject to the same environmental standards
  • this technology offers the chance to revive mining here, it could be huge
  • capturing radionuclides does not make them less radioactive, just easier to handle
  • Where you have huge pools of radioactive material, like at Fukushima, you add graphene oxide and get back a solid material from what were just ions in a solution
  • Then you can skim it off and burn it
  • Graphene oxide burns very rapidly and leaves a cake of radioactive material you can then reuse
  • The low cost and biodegradable qualities of graphene oxide should make it appropriate for use in permeable reactive barriers, a fairly new technology for in situ groundwater remediation,
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Japanese Team Claims Discovery Of Elusive Element 113, And May Get To Name It | Popular... - 0 views

  • Japanese researchers claim they’ve seen conclusive evidence of the long-sought element 113, a super-heavy, super-unstable element near the bottom of the periodic table
  • not yet verified by the International Union of Pure and Applied Chemistry
  • if the IUPAC grants its blessing, the researchers could be the first team from Asia to name one of nature’s fundamental atoms.
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  • Super-heavy elements do not occur in nature and have to be discovered in the lab, using particle accelerators, nuclear reactors, ion separators and other complex equipment
  • Science have been hunting for 113 for nine years, and have claimed to see it a few times already — but the evidence has never been this clear,
  • the team used a customized gas-filled recoil ion separator paired with a semiconductor detector that can pick out atomic reaction products
  • created element 113 by speeding zinc ions through a linear accelerator until they reached 10 percent of the speed of light.
  • ions then smashed into a piece of bismuth. When the zinc and bismuth atoms fused, they produced an atom with 113 protons
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