Minerals/Metals/Alkaline earths

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The alkaline earth metals are the elements in Group 2 of the Periodic Table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).

Berylliums

This is a beryllium-chromium phase diagram. Credit: M. Venkatraman and J.P. Neumann.

Beryllium occurs in a hexgonal close-packed (hcp) crystal structure at room temperature (α-Be).

As indicated in the phase diagram on the left beryllium occurs as (β-Be) which is bcc at higher temperatures up to melting.

Native beryllium is not known to occur on the surface of the Earth, but may eventually be found among beryllium-bearing minerals in small amounts.

Bromellites

Bromellite is BeO, with 50 at % beryllium.[1]

Magnesiums

This portion of the iron-magnesium phase diagram is concentrated on the magnesium-rich end. Credit: A.A. Nayeb-Hashemi, J.B. Clark and L.J. Swartzendruber.

Magnesium has a hcp structure from room temperature up to melting. No other phases occur as is shown in the magnesium-end of the iron-magnesium phase diagram on the left.

Native magnesium is unlikely to occur on the surface of the Earth and is not known to occur.

Chloromagnesites

Chloromagnesite, or chlormagnesite, has the formula MgCl2, with 33.3 at % magnesium.[1]

Forsterites

Mg2SiO4 is the formula for forsterite, with 28.6 at % magnesium.[1]

Forsterite is a member of the olivine group of minerals.[1]

Calciums

This is an Aluminum-Calcium phase diagram. Credit: The ESA IMPRESS Team.

Calcium has a face-centered cubic (fcc) crystal structure at room temperature.

As shown in the phase diagram on the left, it does not change structure up to melting.

Native calcium is not known to occur on the surface of the Earth.

Fluorites

Fluorite has the formula CaF2 with 33.3 at % calcium.[1] Fluorites are also halogen minerals.

Bredigites

Bredigite is α-Ca2SiO4, with 28.5 at % calcium.[1]

γ-dicalcium silicates

γ-dicalcium silicate has the formula γ-Ca2SiO4, with 28.5 at % calcium.[1]

Strontiums

This is a magnesium-strontium phase diagram. Credit: A.A. Nayeb-Hashemi and J.B. Clark.

Strontium at room temperature crystallizes in a fcc structure (α-Sr).

According to the phase diagram on the left, α-Sr transforms to γ-Sr (bcc) at 547°C.

Native strontium does not appear to occur on the surface of the Earth.

Bariums

This is a pressure-temperature phase diagram for barium. Credit: David A. Young, ERDA.

Barium is bcc (α-Ba) at room temperature as the phase diagram on the left indicates. It does change to an hcp structure at high pressures and temperatures.

Native barium is not known to occur on the surface of the Earth.

Radiums

"Solid radium is bcc at room temperature. Radium melts at 973 K.63"[2]

Research

Hypothesis:

  1. Native alkaline earths may require very arid and reducing environments to occur.

Control groups

This is an image of a Lewis rat. Credit: Charles River Laboratories.

The findings demonstrate a statistically systematic change from the status quo or the control group.

“In the design of experiments, treatments [or special properties or characteristics] are applied to [or observed in] experimental units in the treatment group(s).[3] In comparative experiments, members of the complementary group, the control group, receive either no treatment or a standard treatment.[4]"[5]

Proof of concept

Def. a “short and/or incomplete realization of a certain method or idea to demonstrate its feasibility"[6] is called a proof of concept.

Def. evidence that demonstrates that a concept is possible is called proof of concept.

The proof-of-concept structure consists of

  1. background,
  2. procedures,
  3. findings, and
  4. interpretation.[7]

See also

References

  1. 1 2 3 4 5 6 7 Willard Lincoln Roberts, George Robert Rapp, Jr., and Julius Weber (1974). Encyclopedia of Minerals. 450 West 33rd Street, New York, New York 10001 USA: Van Nostrand Reinhold Company. pp. 693. ISBN 0-442-26820-3.
  2. ↑ David A. Young (11 September 1975). Phase Diagrams of the Elements. University of California, Livermore, California USA: Lawrence Livermore Laboratory. pp. 70. http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/07/255/7255152.pdf. Retrieved 2015-08-26.
  3. ↑ Klaus Hinkelmann, Oscar Kempthorne (2008). Design and Analysis of Experiments, Volume I: Introduction to Experimental Design (2nd ed.). Wiley. ISBN 978-0-471-72756-9. http://books.google.com/?id=T3wWj2kVYZgC&printsec=frontcover.
  4. ↑ R. A. Bailey (2008). Design of comparative experiments. Cambridge University Press. ISBN 978-0-521-68357-9. http://www.cambridge.org/uk/catalogue/catalogue.asp?isbn=9780521683579.
  5. ↑ "Treatment and control groups, In: Wikipedia". San Francisco, California: Wikimedia Foundation, Inc. May 18, 2012. Retrieved 2012-05-31.
  6. ↑ "proof of concept, In: Wiktionary". San Francisco, California: Wikimedia Foundation, Inc. November 10, 2012. Retrieved 2013-01-13.
  7. ↑ Ginger Lehrman and Ian B Hogue, Sarah Palmer, Cheryl Jennings, Celsa A Spina, Ann Wiegand, Alan L Landay, Robert W Coombs, Douglas D Richman, John W Mellors, John M Coffin, Ronald J Bosch, David M Margolis (August 13, 2005). "Depletion of latent HIV-1 infection in vivo: a proof-of-concept study". Lancet 366 (9485): 549-55. doi:10.1016/S0140-6736(05)67098-5. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1894952/. Retrieved 2012-05-09.

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