Periodic Table Gallery

An exciting time for chemistry

Two new elements, flerovium Fl and livermoreium Lv have been approved for entry in the Periodic Table of the Elements! They were formerly known by blander names—ununquadium and ununhexium. In honor of the event, I assembled a gallery of periodic tables, but let me tell you more about the table first.

The chemical elements are arranged from top to bottom, in order of lowest to highest atomic number. (Atomic number is the same as the number of protons.) There are 118 elements. 98 are naturally occurring, and 14 occur naturally in decay chains of those 98, up to and including californium. The remaining six elements are lab synthesized.

timmurtaugh via Flickr

Periodic Tattoo

Why is it periodic?

Table rows are “periods” and table columns are “groups.” Some groups have specific names, e.g. the noble gases, occupying the last column on the right. Some rows do too, such as the lanthanides and actinides on the bottom two rows.

The table is also periodic because its inventor, Dmitri Mendeleev, intended for it to be updated periodically, as new elements are found. So Mendeleev’s design had a dual use: for describing how the elements relate to each other, as well as for inferring the properties of new and not yet found elements.

One scientific concept to rebuild civilization

The children’s Periodic Table on the U.S. EIA website has the basics. It links to Los Alamos National Lab’s (LANL) Periodic Table.

Photo of Los Alamos National Labs chemist with period table

Actinides at LANL

Here is a great quote from a recent LANL news story by David Hobart, Actinide Analytical Chemistry, History of the periodic table…and my history with it:

As the legendary physicist Richard Feynman put it, “If some universal catastrophe was to engulf the world and humankind could retain only one scientific concept to rebuild civilization, what would it be? The chemist’s answer is almost invariably the Periodic Table of the Elements.

(more…)

Published in: on 24 March 2012 at 9:02 am  Comments (8)  
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Radiation levels in Japan and the U.S.A.

Radiation levels in Japan post-Fukushima

The source for this chart is Ryugo Hayano, Ph.D. Professor Hayano is the Physics Department chair at The University of Tokyo. Click on the chart to view a larger version, with higher resolution. It used to link directly to the Hayano account on one, then another image sharing site, but both are out of business now. (Lack of persistent URLs is a problem everywhere.)

time series chart of radiation levels

Radiation levels in Japan March 15 to April 10, 2011

I offer my thanks to @hayano and Daniel Garcia. Daniel R. Garcia Ph.D. is a nuclear scientist from France, doing a postdoc at TEPCO, in Fukushima. He was there prior to the earthquake and tsunami. Daniel frequently sends updates as @daniel_garcia_r. He works at the reactor site every day, takes photos, and makes them available via Twitter.

Fukushima nuclear plant

Control board of Fukushima 1 nuclear power plant when all was well

Both Daniel and Professor Hayano are reliable, because they never confuse Becquerel with Sievert with Roentgen. They know radio-isotopes and their half-lives better than nearly anyone. Daniel was needed to assist the press a few weeks ago, when there was confusion between Cesium 137 versus Iodine 137 and again between Iodine 131 versus Uranium 137.

Other locales, other radiation levels

The Radiation Network is an excellent resource for radiation information in the U.S.A. and other parts of the world. It is a network of civilian volunteers using a protocol to report radiation readings, 24 hours a day, 7 days a week. Sensor stations are located throughout the contiguous 48 states, Hawaii,  Alaska and Norway. There was one in Northern Japan. Sadly, that sensor went off-line last month.

The Radiation Network is non-profit, all volunteer and headquartered in Arizona. Tim is the public face of the Radiation Network. Using software developed for this purpose, Tim collects and aggregates the real-time data from the sensor stations, then updates the map online with the readings at one-minute intervals. The Radiation Network went online nearly a decade ago, and offers reliable baseline measurements for comparison. This facilitates detection of any incident. The criteria for elevated radiation levels include:

  • Rule-out protocol for false positives, e.g. spikes due to sensors  malfunctioning;
  • Level of radiation that is significant: Higher than the threshold AND sustained, and how long “sustained” is;
  • Exogenous causes such as geography. Readings in Colorado are always higher due to the higher elevation,

The website is basic but functional. There are Radiation Network maps of Europe, Japan, and the US (broken out for Alaska and Hawaii), and a message. The message is a running log of updates.

Published in: on 10 April 2011 at 8:59 am  Leave a Comment  
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WeatherBill raises new round of funding

With the addition of $42 million in a Series B round, funding in this catastrophic insurance risk startup company now totals $60 million. The total is primarily due to today’s large infusion of cash from Google Ventures.

What is WeatherBill?

With statistical analysis and distributed computing for better weather forecasting, WeatherBill can offer farmers more competitive insurance rates, specifically, a personalized insurance policy. The company was founded four years ago by two former Google employees, one of whom was Chief Technology Officer at Google.

I hope WeatherBill is successful. This story is a welcome change from news about over valued social media companies, e.g. TechCrunch’s recent post about J.P. Morgan’s rumored investment of $450 million in Twitter. It is a welcome change when a major venture capital investment is made in a business targeting farmers!

Rainmakers For WeatherBill

WeatherBill Inc. is announcing $42 million in Series B funding from Google Ventures, Khosla Ventures and several previous investors… WeatherBill aggregates large amounts of weather data from the National Weather Service and other sources to run large-scale simulations that assess the probability of weather occurring several years in advance anywhere on the globe.

“Agriculture is an unusual area for venture capital, but we submit that agricultural technology has the same potential as biotechnology had in pharmaceuticals or chips had in telecommunications,” Khosla said.

via blogs.wsj.com (28 February 2011)

Published in: on 1 March 2011 at 12:48 am  Comments (2)  
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Small Satellites Increase Access to Space

SRI International and NASA gave the final send-off to Radio Aurora Explorer (RAX) and its bevy of diminutive CubeSat satellites on November 19, 2010 as part of a space, weather, and atmospheric research project. The launch was accomplished with the assistance of an elderly Minotaur IV rocket by the Department of Defense’s (DOD) Space Test Program.

Genesat 1 small satellite

This is a CubeSat

The RAX mission goal is to improve understanding of intermittent and unpredictable distortion of earthly communications signals. Radio frequency and global positioning system (GPS) signals are adversely affected by upper atmosphere turbulence. This turbulence is like a whirlwind of ionizing activity, due to intense electrical currents that propagate from time-to-time through space. Solar wind storms, supposedly due to sunspot activity or coronal flares are ultimately responsible.

The fact that fluctuating levels of electrical activity in the upper atmosphere cause radio signal disruption is well-known. The disruption is intensely annoying for amateur radio operators such as myself, as I recall from my days as KA5JQF! It is annoying for GPS users, and can be a critical concern for navigation systems on Earth. With the data collection and experimental results from the RAX research, scientists will gain a better understanding of ionospheric turbulence. Near-space weather forecasting of sorts will finally become a reality.

Easier in near-space than at home

My analogy with terrestrial weather forecasting actually overstates the complexity! Predicting incidence and duration of radio signal disruptions, due to high solar activity and geomagnetic conditions, will probably be easier than meteorological forecasting of Earth’s very complicated weather systems.

Space weather prediction is challenging primarily because of the difficulty of collecting data, and corroborating cause and effect.

Ecumenical space missions

The RAX mission deserves special attention for another reason. It requires the collective participation of many astrophysicists, geophysicists, astronomers and graduate students from around the world. Radio telescopes and scientific radar installations in Alaska, Norway and Puerto Rico’s Arecibo are hubs for the research project team.

rocket launch photo

Minotaur rocket launching cube satellites into space – Image courtesy of NASA

I hope we’ll see a many more CubeSats in days to come, and for a variety of purposes. They were developed to increase both research and educational access to space. They are inexpensive, and lower the cost of space research. RAX is the first NSF satellite mission to be launched by the DOD .

Space missions using CubeSats don’t need vast infrastructure development and funding, unlike Apollo. Missions can be initiated by smaller, less wealthy countries and research institutions. CubeSat design timelines are very short, compared to traditional satellite technology. That’s why they’re particularly good for student involvement.

Published in: on 8 December 2010 at 11:30 pm  Comments (2)  
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Rare-earth metal sources and shortages

A better title would have been Postcard: People’s Republic of China, except for the fact that I’m in Arizona. Let’s begin with the possibly impending rare-earth metals shortage.

What are rare-earth metals?

A shortage of rare-earth metals seems arcane. What are they? Depending on who you ask, they are 15 to 30 elements with the following common properties: A silvery or grey appearance, high luster that is quick to tarnish in air, and very high electrical conductivity.

Rare-earth metals are not all that rare. They earned their name from the tedious process by which they were extracted prior to advancements in metallurgy in the 1950s.

Periodic table

Lanthanide series and a few more: The rare-earth elements

Here is a most beautiful periodic table of the elements by Perioden System. If you like the periodic table, I recommend having a look at their interactive version. Super-high resolution downloads are available free.

The 17 elements that are universally considered rare-earth elements are also known as the Lanthanides. The name is appropriate, as it is derived from the Greek lanthanon, meaning “I am hidden”. The Lanthanides are on the bottom drop-down of the chart, numbers 57 lanthanum, through 71 lutetium. Elements scandium and yttrium comprise the rest of the rare-earth metals. Several members of the second series, the Actinides, are sometimes classified as rare-earth, including thorium and uranium.

Precious metals, which are refined from the elements gold, platinum, palladium, silver, rhodium and iridium are NOT rare-earth metals.  This confusion is common. Referring to the periodic table will clarify, as precious metals have atomic numbers 45 through 47 and 77 through 79.

China mines 95% of the world’s rare-earth metals

Physics Today Online

Impending rare-earth metals shortage?

The People’s Republic of China has global dominance of rare-earth ore mining. This presents a geopolitical risk exposure, as the United States and the rest of the world have been highly dependent on China as a source of rare-earth metals for decades.

Demand for rare-earths is expected to increase as green technologies gain more acceptance and use. Special batteries use rare-earth metals, such as the batteries in mobile phones. Hybrid car motors require magnets made from dysprosium, element 66. Permanent magnets made from neodymium are the strongest magnets made, and used for munitions and guidance systems. All of the heavy rare-earth metals such as dysprosium are mined in China.

“Heavy” refers to heavy nuclei, which simply means a larger number on the periodic table. In general, the heavier nuclei rare-earth elements are the most sought after.

Expertise is more limited than reserves

Supply is not the only problem. A third of the estimated reserves of rare-earth elements are in the United States. However, concentration of rare-earth mining activity has shifted the world’s rare-earth knowledge base, from the United States and South America, to China. Most of the world’s material scientists and geologists who are experts in rare-earth metal mining and metallurgy reside in China.

Consequences of expertise localization are dramatic. The division of General Motors researching miniaturized magnets shut down its US office and moved the entire staff to China in the late 1990s.

According to a May 2010 article in Physics Today, Concern grows over China’s dominance of rare-earth metals, the owner of Mountain Pass mine in California said,

Little rare-earth expertise remains in the US. I have 17 engineers and scientists competing with over 6000 scientists in China. And I can’t find any students from any university in the US that have any experience with a rare-earths curriculum today.

USGS summary of RE element mining activity

Rare-earth oxide production per year

On September 1, 2009, China announced plans to cut its rare earth mining quota to 35,000 tons per year in 2010 – 2015, in order to conserve scarce resources. Illegal rare earth mines are common in rural China and release toxic wastes into the general water supply, presenting environmental concerns.

Published in: on 17 May 2010 at 1:45 am  Comments (5)  
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