Military Applications of the REEs in the United States

The U.S. Department of Defense (DoD) uses rare earths in a number of military technologies and is dependent on their availability. (1) China’s near monopoly in rare earths has the attention of American security experts, the DoD, and the U.S. Congress.The U.S. rare earths policy is the DoD policy. Since its adoption in 2011, there has been a significant improvement in rare earths markets. The existing policy, combined with natural markets forces, are working together to improve supply, demand, and market prices. U.S. lawmakers need to resist pressures to pass needless legislation that will only disrupt natural market forces, increasing the cost while decreasing long-term availability.(1)

Rare earth elements play an essential role in the US national defense. The army uses night-vision goggles, precision-guided weapons, communications equipment, GPS equipment, batteries, and other defense electronics. Technologies of this sort give the United States military an enormous advantage. Rare earth metals are key ingredients for making the very hard alloys used in armored vehicles and projectiles that disintegrate upon impact. (2)

Substitutes can be used for rare earth elements in some defense applications; however, those substitutes are usually not as effective and that diminishes military superiority. Several uses of rare earth elements are summarized in the following table. (2)

Table 1. Defense Uses of Rare Earth Elements

Defense Uses of Rare Earth Elements

Lanthanum night-vision goggles
Neodymium laser range-finders, guidance systems, communications
Europium fluorescents and phosphors in lamps and monitors
Erbium amplifiers in fiber-optic data transmission
Samarium permanent magnets that are stable at high temperatures
Samarium precision-guided weapons
Samarium “white noise” production in stealth technology

 

(1)¬†LTC William R. Glaser : ”U.S. Rare Earths Policy: Digging Out of the¬†Rare Earths Quandary ” ¬†(luce.nt)

(2) http://geology.com/articles/rare-earth-elements/ (2017-02-14)

Ytterby – a Landmark for the History of Chemistry

When it comes to the discovery of elements on the periodic table, you can divide the world into two parts‚ÄĒYtterby, and everywhere else. Ytterby (“itt-ter-bee”) is a village on a little island outside of Stockholm. But no place on earth has been more important to the periodic table. A few places‚ÄĒif you count Latin names‚ÄĒcan brag that two elements have been named for them. Ytterby has four. And it could have had more, since three other elements can trace their discovery to a modest mine that once supported the community there. (1)

1024px-Ytterby_gruva_2769

1. The quarry in the tiny village of Ytterby (2)

The Ytterby mine opened not to find new elements (no money in that) but to find a mineral called feldspar. Feldspar is crucial for making Chinese porcelain, which Europeans had coveted since the days of Marco Polo in the 1300s. Two European chemists finally figured out how to make porcelain on their own circa 1700. (One of the duo, a teenager, had been condemned to death as a swindler and failed royal alchemist; he promised to discover the secrets of porcelain in exchange for his life, and succeeded.) Swedes liked porcelain because it made better stoves to warm their homes than iron did, and the mine ( Ytterby gruvain Swedish) opened in the late 1700s to cash in on the demand.

The chemist Lieutenant Carl Axel Arrhenius (1757-1824), student of the Swedish chemist Berzelius, found in 1787 in the dumps of the Ytterby quarry (for information on Ytterby and its quarry, see below) an interesting find, an exceptionally heavy piece of black broken rock. He named it ytterbite after the location with the standard suffix -ite added to indicate a mineral. This stone was sent to, among others, Johan Gadolin (1760-1852), professor at Åbo University. (3)

Gadolin found that the “black stone of Ytterby” was composed of 38% of a new “earth type” (“earths” are compounds of elements, usually oxides). He concluded his analysis in 1794 and named this new earth¬†ytterbia. His analysis was confirmed three years (1797) later when Anders Gustaf Ekeberg (1767-1813) analysed a larger sample. Ekeberg shortened the name to¬†yttria. In the decades after Antoine Lavoisier developed the new chemistry built on the concept that earths could be reduced to their elements, the discovery of a new earth (with name ending in “a”) was regarded as equivalent to discovering the element within. Thus the element reducible from the earth¬†yttria¬†would be Yttrium.

However, yttria was in fact it was a mixture of a number of metal oxides. In 1843, Carl Gustav Mosander (1797-1858) separated yttria into three parts, one of which kept the original name:

  1. Yttria (with a colorless salt and colorless oxyde),
  2. Erbia (yellow oxyde, colorless salt), and
  3. Terbia (rose oxyde, red salt).
    (Later Erbia and Terbia were interchanged).

schema_yttriaschema_ceria

2. The flow chart of the discovery of the elements from ‘yttrium” and ”Ceria”(3)

 

1. www.slate.com (January 2015.)

2. http://en.wikipedia.org/wiki/Ytterby#mediaviewer/File:Ytterby_gruva_2769.jpg

3. www.vanderkorogt.net (January 2015.)

 

Rare Earths for Medical Applications

Lanthanides are used in many medicinal applications, such as in anti- tumor agents and kidney dialysis medicine. One of the most known application of these elements is the use of Gadolinium in Magnetic Resonance Imaging (MRI). (1)

The first medical applications in this field became reality shortly after the development of magnetic resonance imaging and the introduction of this technique in medical diagnosis. MRI is an NMR technique that visualizes, with a very high resolution, the morphology of the body. The intensity of each voxel in a three-dimensional image reflects the intensity of the 1H NMR signal of the water in the corresponding part of body. The intensities of these signals and, consequently, the contrast of the images are dependent on magnetic relaxation of the nuclei. Relaxation can be enhanced by paramagnetic compounds, and the lanthanide ion Gd(III) with its seven unpaired electrons is the paramagnetic champion of the periodic table. This ion is ideal for improving the contrast in MRI scans. Gd(III) chelates such as Gd(DTPA) and Gd(DOTA) have been developed that have a very low toxicity, even at the relatively high doses in which they are applied. These contrast agents are as safe as an aspirin, and they have contributed to the success of MRI in clinical diagnostics. Nowadays, about 30% of MRI scans are performed after administration of a Gd(III)-based contrast agent.The luminescent properties of the lanthanides also have been utilized in medical diagnosis. A variety of luminescent bioassays and sensors have been developed that take advantage of the unique luminescent properties of these elements, such as a relatively long-lived emission. (2)

 

MRI-scan-room

Fig 1. Magnetic resonance imaging (MRI)

Europium compounds, for example are often used in molecular genetics to mark specific strands of DNA. Europium oxide was also used in cathode ray television sets as the red glowing dye in the trichromatic setup. (3)

The¬†treatment for high blood phosphate uses compounds called phosphate binders; in the gut these prevent phosphate uptake from the diet. ‘The ideal phosphate binder should have low solubility and little or no systemic adsorption. It should be non-toxic and available in a palatable oral dosage form. Aluminium and calcium based phosphate binders can cause problems due to metal ion absorption, he said. Fosrenol¬†(lantnanum carbonate chewable tablets) avoids the adverse effects associated with earlier drugs because it cannot cross the gut lining and so is not transmitted to the rest of the body. (4)

A new focus nowadays has been put on the anti-cancer treatment use of lanthanides, because of their therapeutic radioisotopes. The dominant pharmacological applications of lanthanides are as agents in radioimmunotherapy and photodynamic therapy. (5)

(1) http://nuclearweaponarchive.org/Usa/Med/Lbfm.htm

(2) http://pubs.acs.org

(3) Shriver and Atkins Inorganic Chemistry

(4) http://www.rsc.org

(5) Kostova, I. Current Medicinal Chemistry РAnti-Cancer Agents, Lanthanides as Anticancer Agents, Volume 5, Number 6, November 2005, pp. 591-602(12)

Neodymium Magnets in Alternative Medicine

Magnetic fields are all around us and a major part of everyday life. They add greatly to the quality of modern living. The sunlight, which makes life possible, is an electromagnetic field; everything that generates, transmits or uses electricity produces electric and magnetic fields and, of course, the television companies send out their product as electromagnetic radiation.

Some alternative medicine sources state that magnetic fields generated by small permanent magnets could actually improve your health and benefit to your overall well being. Magnet therapy or magnotherapy is a pseudoscientific alternative medicine practice involving the use of static magnetic fields. Practitioners claim that subjecting certain parts of the body to magnetostatic fields produced by permanent magnets has beneficial health effects.

Products include magnetic bracelets and jewelry, magnetic straps, shoe insoles, mattresses, magnetic blankets (blankets with magnets woven into the material), magnetic creams, magnetic supplements, plasters/patches and water that has been “magnetized”. Application is usually performed by the patient.

     gold-plated-torque-magnetic-bangle-large                       magnetic-therapy_950

Fig 1. Magnetic straps                                                           Fig 2. Magnetic bracelet

 

MS115.websml

Fig 3. Magnetic insole

 

Due to the variety of electromagnetic fields that naturally occur within the body, there is interest in magnet therapy for medical conditions. For example, nervous system transmissions and related muscle contractions are associated with magnetic activity. The heart generates the largest magnetic field in the body. Several other activities in the body are associated with magnetic activity. 

At one time it was thought that abnormal magnetic fields in the body might result in certain disease states and that magnets could play a role in making these magnetic fields normal again.

You may hear that magnets attract the iron in red blood cells, resulting in increased circulation. But this is wrong. The iron in blood cells is not in a magnetic form. However, magnets, in theory, could have an effect on other charged molecules in the blood and other parts of the body.

No scientific evidence has been provided as to these magnets could actually benefit your health and in some cases, these magnets could actually pose a danger. In general, when using neodymium magnets for medical purposes, you should keep in mind these few things:

1) Scientific evidence does not support the use of magnets for pain relief.

2) Do not use magnets as a replacement for conventional medical treatment or as a reason to postpone seeing your health care provider about any health problem.

3) Magnets may not be safe for some people, such as those who use pacemakers or insulin pumps, as magnets may interfere with the devices. Otherwise, magnets are generally considered safe when applied to the skin.

4) Tell all your health care providers about any complementary health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

 

References :

David Jeffers, (1996) “Electric and magnetic fields and health”, Structural Survey, Vol. 14 Iss: 1, pp.4 – 8

Park, Robert L. (2000). Voodoo Science: The Road from Foolishness to Fraud. New York, New York: Oxford University Press. pp. 58‚Äď63

Singh, Simon; Edzard Ernst (2008-04-08). “Are we being hoodwinked by alternative medicine? Two leading scientists examine the evidence”. Daily Mail. Retrieved 2009-08-18.

www.webmd.com (June 23rd, 2014.)

www.nccam.nih.gov (June 23rd, 2014.)