SERTARUL CU GANDURI

06/09/2016

Keith Veronese – Rare: The High-Stakes Race to Satisfy Our Need for the Scarcest Metals on Earth (3)

Filed under: FRAGMENTE DIN CARTI SI BLOGURI — afractalus @ 17:51

rare-4   – Highlight Loc. 1326-29 : The title „wonder drug” is thrown around frequently in the pharmaceutical world, but a small-molecule drug that can effectively treat lung, ovarian, bladder, cervical, and testicular cancer with fewer side effects than radiotherapy? The integration of platinum atoms in a small molecule to create a drug yields a tool effective at treating a wide variety of cancers. Cis-diamminedichloroplatinum(II), which moonlights as the much-easier-to-say trade name cisplatin, is a simple molecule at the forefront of cancer treatment starring a single atom of platinum at its core.
– Highlight Loc. 1344-47 :  Cisplatin brings about apoptosis in cancer cells shortly after reacting with the cell’s DNA. Once bound to DNA, the information-carrying molecule becomes cross-linked and thus unable to divide—a step necessary for the cell to undergo its form of reproduction: fission. If tumor cells cannot reproduce, the runaway train of unbounded growth is halted.
– Highlight Loc. 1347-50 : Cells can stimulate the repair of DNA after determining that it can no longer divide, however, once the repair efforts are unsuccessful—thanks to the presence of cisplatin—the cell starts its own self-destruction sequence—apoptosis—resulting in the destruction of the tumor cell. If apoptosis can be successfully triggered in enough cancer cells, the tumor will begin to shrink.
– Highlight Loc. 1364-68 : Thulium, one of the seventeen rare earth metals (and one of the rarest, period), is a possible candidate for use in brachytherapy. Brachytherapy is a form of radiation treatment wherein the metal of import, in this case thulium, is placed in proximity to the tumor. The thulium-170 isotope emits x-rays and has a relatively short half-life, allowing for the placement of a steadily firing atomic gun in the vicinity of cancerous cells, particularly in the case of prostate cancer.
– Highlight Loc. 1832-34 : In 1911 Charles James reacted the remnants of ore containing thulium with bromine and crystallized the compound in water to obtain a slightly purer form of thulium, repeating the process a reported fifteen thousand times before he obtained a sample of metallic thulium that met his standards for purity.
– Highlight Loc. 2116-20 : De Ulloa noted a particulate found in riverbeds that drew the ire of gold miners in Colombia and Ecuador. The silver and black specks would not melt in the heat of a kiln. If introduced to molten gold, the particulates would discolor the final purified ingot and lower the value in the eyes of prospective purchasers. De Ulloa noted that miners and metal workers would often throw this metal back into the river, giving the silver and black sand the description it carries today—platina del Pinto, a phrase translating to “little silver of the Pinto River,†or what we now call platinum.
– Highlight Loc. 2120-22 : De Ulloa’s observation of platinum would go overlooked at this junction in history, but by no fault of his own. Spain soon sent de Ulloa to Peru and placed him in charge of their cinnabar mines, a series of deadly caverns storing the mercury Spain needed to mine silver deposits in other parts of Peru.
– Highlight Loc. 2140-41 : De Ulloa proved to have an impressive resume and offered a concrete identification of platinum. But historians have lifted up as his adversary a bewildering sixteenth-century Italian physician and scholar known best for his ego: Julius Caesar Scaliger.
– Highlight Loc. 2164-66 : General use of the metal we now call platinum dates back thousands of years earlier, thanks to artifacts found in the Egyptian city of Thebes. The foremost relic is the Casket of Thebes, a sarcophagus dating to 700 BCE and featuring platinum alongside gold and silver hieroglyphic inlays.
– Highlight Loc. 2204-9  : What set Antonio de Ulloa and Julius Caesar Scaliger apart in the discovery of platinum is their mention of the metal in texts each wrote later in life. What may be more telling, intellectually, is information pointing us in the direction of those who championed the use of platinum by manipulating its uniquely stable characteristics. British scientist Charles Wood smuggled a small cache of platinum from South America in 1741 and distributed the metal among colleagues in Europe, proselytizing its characteristics with so much vigor that the scientific community of his day added platinum as the eighth known metal, making it the first added since ancient times (iron, gold, silver, tin, mercury, lead, and copper round out this primitive roll).
– Highlight Loc. 2214-16 : The ability of a large piece of platinum to remain inert—an overall resistance to chemical reactions—led France to painstakingly manufacture a platinum bar of exactly one meter in length to use as the universal standard of length in the metric system. 9
– Highlight Loc. 2365-67 : Neodymium ”one of the two elements derived from Carl Gustaf Mosander’s incorrect, but accepted, discovery of didymium in 1841—is the most widely used permanent magnet, with the rare earth metal being found in hard drives and wind turbines as well as in lower-tech conveniences like the button clasp of a purse.
– Highlight Loc. 2369-70 :  Niobum receives its name through a quirk of Greek mythology. Traditionally, Niobe is known as the daughter of Tantalus (for whom the rare metal element tantalum is named).
– Highlight Loc. 2374-76 : Niobium, a metal typically used to make extremely strong magnets, is also quite stable and has the added bonus of mild hypoallergenic properties—a boon to the medical world in which niobium became an obvious choice for use in implantable devices, specifically pacemakers.
– Highlight Loc. 2421-24 : Hafnium is a rarely used metal, but the seventy-second element on the periodic table could change the future of warfare, thanks to the outcome of a handful of experiments conducted in a small Dallas, Texas, lab. The experiments involved exposing a minute amount of a nuclear isomer of hafnium-178 to a beam of x-rays.
– Highlight Loc. 2432-33 : Collins reported that the energy released exited as gamma rays—gamma rays and x-rays are simply forms of energy—and appeared to have shown that the long-speculated possibility of induced gamma emission was now a reality.
– Highlight Loc. 2657-61 : Polymetallic nodules—baseball-sized deposits of minerals and metals—line stretches of the ocean floor. These deposits form in a manner similar to pearls, with the layers of a polymetallic nodule slowly added over time, while the cores are created out of bits of bone or tooth from recently deceased sea life. 27 The layers are primarily composed of manganese, but copper and cobalt are also present, along with small amounts of eleven of the seventeen rare earth elements.
– Highlight Loc. 2807-11 : Armed with a bottomless checkbook and a lifelong love of science and the final frontier, Garriott purchased the Lunokhod 2 for $68,500 in 1993 from Sotheby’s New York. Lavochkin, a state-owned Russian aerospace company, signed the rover to Sotheby’s in an auction devoted to selling memorabilia from the Russian space program to North American bidders just over twenty years ago. In addition to the 239,000 miles separating Garriott from the Lunokhod 2, Lavochkin did not know the exact location of the rover, since the Soviet Union lost communications with the craft in 1973.
– Highlight Loc. 2817-19 : The Lunokhod 2 is far from the only spacecraft sitting on the moon; close to seventy-five other craft in various states of assembly reside on the surface, abandoned for decades. What is unique about the Lunokhod 2? The purchase made Garriott the sole publicly known private owner of an item outside of Earth’s orbit.

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