字幕表 動画を再生する 英語字幕をプリント Occasionally in books or movies the story will feature a fantastic new and rare element with seemingly impossible Characteristics in the Lord of the Rings mithril is a light but extremely strong metal found only within the mines of moria In James Cameron's Avatar this highly valuable metal was called unobtainium a room-temperature Superconductor found only in small quantities on the distant moon called Pandora most recently in Black Panther This element was the metal vibranium which can absorb any and all vibrations found exclusively in the fictional African country of Wakanda These super materials might seem far-fetched or entirely made up to serve the plot But what if I told you there was an element found on earth that did have special and amazing characteristics Similar to these examples and was really only found in one place This metal is used on anything from aerospace components to lasers from helping treat cancer to fueling nuclear batteries What a foe is also found in fiber optic cables and could also be added to fertilizers to improve plant and livestock productivity on top of that This metal is essential in all modern electronics and without them our phones and computers could not function You might say this is too good to be true, but let me introduce you to rare earth elements Okay, so there are actually 17 elements included under this designation. Not just one but for most purposes they're grouped as a single unit Why you might ask well 15 occupy a single row on the periodic table and the other two scandium in each room aren't far away Their proximity to one another on the periodic table means they all have very similar properties Because of their similar sizes and densities they typically stick together in the Earth's mantle and therefore are deposited in or together typically Where you find one rare earth element, you'll find many others as well and despite their name They're not all that rare We can see on a graph like this where basically the higher the elements are on the graph the more abundant They are in the earth. So up here We have very common elements like oxygen and silicon, but as we go down we'll see most rare earth It's fall somewhere in the middle of the range while precious metals like gold and platinum are all the way down here the most common Of the rare earth elements cerium is about as abundant as copper or nickel on the earth Only one of the 17 rare earth elements is truly rare and that's promethium Every isotope of this element is radioactive meaning it will always decay into other elements over time It's estimated that less than 600 grams of naturally occurring promethium exist on earth But overall except for promethium. They're only moderately uncommon at best The reason they're called rare has more to do with their distribution take a gold despite it being far more rare than these it occurs in the crust is Concentrated veins and this makes the extraction and processing relatively simple and therefore cheap rare earth elements on the other hand almost never occur and Concentrated deposits and instead are much more evenly spread across the planet This makes the mining and refining process far less efficient, and therefore makes their overall extraction more expensive so with few economically Exploitable deposits despite being fairly abundant refined and usable rare earth elements remain well rare Which is a real shame because these things are awfully useful for example scandium can be alloyed with aluminum to drastically increase Tensile strength creating an incredibly strong and light metal used by aerospace companies to decrease chances of failure Nutriyum is used in treatments of certain cancers in a method called selective internal radiation therapy. It's most effective against liver cancer Neodymium is one of the strongest and naturally magnetic materials out there and when alloyed with iron and boron can make those crazy Magnets, you'll see on other science channels promethium the super rare one has been proven to work in nuclear batteries ytterbium is used in stress gauges monitoring for earthquakes and Basically all of these in some form or another are useful in making lasers but when used together their usefulness increases exponentially Several of them are crucial and magnet production which other than being a ton of fun to play with are also crucial Components of engines used more and more on things like electric cars and generators for things like aircraft and wind turbines and even in computer Hard drives many rare earth elements have even been used in agriculture to increase plant growth Productivity and resistance to stress with no observed and negative consequences on the environment or food safety Even adding these elements to livestock feet has caused more growth and even higher egg production from chickens But perhaps most importantly many rare earth elements are essential in electronics, you know The thing you're watching this video on and without them are phones computers and televisions could not function in a rapidly modernizing In advancing world these 17 elements are becoming more and more crucial to our functioning There's only one problem today just one country accounts for over 90% of the global rare earth production China most of this comes from mines in the province of Inner Mongolia the southern provinces and the western province of Sichuan These three areas account for 98 percent of China's total rare earth production and once mined much of these rare earth metals will travel to cities like Shanku where they'll go directly to huge tech companies like Apple and Samsung that have factories putting together Electronics in the city this gives China almost complete control over not only rare earth elements But also the manufacturing of things like smartphones and new computers what has certain countries like the US even more worried however Is the importance of rare earth elements in our defensive weaponry just like consumer electronics the electronics used by the military Things like computers for navigation or steering missiles also rely on these scarce elements without China's cooperation Every military outside of China's could be left in the technological dark at least for a time in 2010 They've reduced the rare earth exports by 40% and sent prices outside of their borders soaring Not only did this create an international shortage. It also gave Chinese companies an insurmountable competitive advantage on the global stage in 2014 the United States the European Union and Japan Confronted China's export quotas through the World Trade Organization, and it was ruled in early 2015 that China had to lift its quotas So basically rare earth elements are vibranium and China is Wakanda but like not in a cool way as China continues its attempts to limit its rare earth exports an International search has begun to find new potentially more reliable sources of these essential metals surveys show that China while extremely rich in rare earth elements really only contains about 23% of the total proven world of deposits by many measurements The United States has the second greatest rare earth element potential And in fact before China ruled the market just a single mine in southeastern, California The mountain pass mine supplied the majority of the world's rare earth demand the United States also contains substantial Rare earth deposits in the southeast from Florida to North Carolina as well as in Idaho and Montana It's estimated that opening mines in all of these places could not only eventually surpass China's production But could alone support the growing rare earth demand for the next 280 years another country with large rare earth deposits is Russia with development of the Tom tour rare earth mined reportedly starting in 2013 this single mine has been confirmed to contain 154 million tons of rare earth ore or about 12% of the world's proven or Australia has also been looking into the rare earth potential with the knowlins project and the Mount Weld Deposits receiving a lot of attention recently a Canadian company recently discovered large deposits of rare earth ore in Ontario and Quebec provinces while mining for uranium Specifically the highest lake has given promising results other countries with noted rare earth potential include Malaysia India Afghanistan Egypt South Africa and Brazil, so with so many possible suppliers of these incredibly valuable resources How does China seem to maintain a monopoly on rare earth production? well in short Economics you see while rare earth ore is highly sought after it will usually only contain anywhere from five to twelve percent actual rare earth Elements with the rest being common oxides but really only ores containing eight percent or higher can really be processed Profitably at the moment mining and refining of rare earth elements is highly costly and China seems to be the only country right now with enough of an Economic machine to absorb these costs and still profit this is the result of the cheap labor found in China as well as the government's Prioritizing the development and maintenance of their dominance in the field add on to that The mining of rare earths is highly damaging to the environment not only by scouring the land but also leaking heavy metals into sir Pounding lands and water supplies and any country with moderate environmental protection legislation have real trouble developing rare earth mines so China has the perfect mix of cheap labor and Hands-off environmental policies to allow rare earth mining to thrive the mountain pass mine The one that once has supplied most of the world's rare earth elements closed in 2002 with an estimated 22 million tons of rare earth materials still in the ground It didn't close because they ran out of materials But because they were no longer profiting from their Operations in large part due to competition from China but as China clamps down further on their exports they've begun to tip the scales Against themselves and have made rare earth mining and processing profitable outside of their borders Which is why we see so many countries just beginning to develop their own deposits China has even tried to purchase and control mines outside of their borders and attempts to keep control over the industry But like at the end of black panther this control might change soon if you enjoyed this How about giving a like if you'd like to see more videos like this the subscribe button is there for a reason? Hopefully I'll have another video coming next week. So make sure to check back then if you want some updates You can follow me on Twitter. Other than that. Thanks for watching
B1 中級 米 Rare Earth Elements: China's Vibranium? 9 1 joey joey に公開 2021 年 06 月 05 日 シェア シェア 保存 報告 動画の中の単語