Bad Pyrmont Spa (open access)

Bad Pyrmont Spa

Photo depicts the Bad Pyrmont Spa in western Germany which is known for its therapeutic baths and vapor cave. The paragraph on the bottom of page 70 gives details about the photo and the spa.
Date: Winter 2015
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Object Type: Article
System: The UNT Digital Library
Rediscovery of the Elements: The Rare Earths - The Beginnings (open access)

Rediscovery of the Elements: The Rare Earths - The Beginnings

This article explores the rare earths, the chemically similar elements that occupy the f-block of the Periodic Table and the Group III chemical family. The articles shows the locations that certain rare earths were originally found. It also gives details on where the elements can be found currently, as well as major production areas. The cover of the Fall 2015 Hexagon journal (Vol. 106, Issue 3) features the Mountain Pass rare earth ore body in Southern California, which is mentioned in the article on pages 40-45 of the journal. A description of the photo on the cover of the journal can be found on page 38.
Date: Autumn 2015
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Object Type: Article
System: The UNT Digital Library
Rediscovery of the Elements: The Rare Earths - The Confusing Years (open access)

Rediscovery of the Elements: The Rare Earths - The Confusing Years

This article gives a timeline of research conducted on the rare earths, 17 elements found in the f-block and Group III chemical family of the Periodic Table. It covers discoveries made after the success of Swedish chemist, Carl Gustaf Mosander. The article describes the categorization of the rare earths that took place after Mosander's time, as well as separation techniques that developed.
Date: Winter 2015
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Object Type: Article
System: The UNT Digital Library
20 Mule Team (open access)

20 Mule Team

This photograph from the front cover of an issue of the Hexagon Journal displays the mock 20 mule team that stands outside of the Rio Tinto Borax Museum in Boron, California. The mule team depicts the original mode used to transport the chemical compound, borax, out of Death Valley between 1883 and 1888. A description of the photograph is shown on page 23 of the journal.
Date: Summer 2015
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Object Type: Clipping
System: The UNT Digital Library
Rediscovery of the Elements: Sir Humphry Davy and the Alkalis (open access)

Rediscovery of the Elements: Sir Humphry Davy and the Alkalis

Article provides information on the history of alkalis, particularly discoveries associated with potassium and sodium. The article also gives information on Humphry Davy, the first person to prepare alkalis in elemental form.
Date: Summer 2015
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Object Type: Article
System: The UNT Digital Library
The Reaction Kinetics of Amino Radicals with Sulfur Dioxide (open access)

The Reaction Kinetics of Amino Radicals with Sulfur Dioxide

Abstract: Application of the laser photolysis–laser-induced fluorescence method to the reaction NH2 + SO2 in argon bath gas yields pressure-dependent, third-order kinetics which may be summarized as 𝑘 = (1.49 ± 0.15) × 10^−31 (𝑇/298 K) − 0.83 cm^6 molecule^−2 s^−1 over 292 – 555 K, where the uncertainty is the 95% confidence interval and includes possible systematic errors.The quenching of vibrationally excited NH2 is consistent with a high-pressure limit for NH2 + SO2 of (1.62 ± 0.25) × 10^−11 cm^3 molecule^−1 s^−1 over the temperature range 295–505 K, where again the 95% confidence interval is shown. Abinitio analysis yields a H2N – SO2 dissociation enthalpy of 73.5 kJmol−1, and comparison with RRKM theory and the exponential down model for energy transfer yields ⟨Δ𝐸⟩down = 350 cm^−1 for Ar at room temperature.
Date: April 29, 2015
Creator: Gao, Yide; Glarborg, Peter & Marshall, Paul
Object Type: Text
System: The UNT Digital Library