| 单词 | tantalum |
| 例句 | One was composed of the metals vanadium, niobium, tantalum, molybdenum and tungsten. Electron-rich metals make ceramics tough to crack 2023-10-19T04:00:00Z A number of companies sourcing minerals such as tin, tungsten, tantalum and gold are also failing to meet disclosure requirements with the U.S. Some U.S. companies still failing to meet conflict minerals rules, GAO says 2023-07-20T04:00:00Z Lepidolite extraction and smelting produces toxic by-products like thallium and tantalum that cause severe water pollution, said Wu Wei, an assistant professor at Xiamen University. Analysis-In China's lithium hub, mining boom comes at a cost 2023-06-15T04:00:00Z The mock pits, made of dense metals such as lead, tantalum, or depleted uranium, have properties similar to plutonium—minus its tendency to fission. Trust but verify: Can the U.S. certify new nuclear weapons without detonating them? 2023-04-20T04:00:00Z Numerous rebel groups have funded their occupation of the region through exploiting minerals such as tin, tungsten, tantalum and gold. DR Congo conflict: Why Kenyan troops are joining the battle 2022-11-05T04:00:00Z In 2010, in response to war in the Congo, Congress required companies to disclose the origin of so-called conflict minerals — tantalum, tin, gold and tungsten — and promise their sourcing does not benefit armed groups. ‘The Sacrifice Zone’: Myanmar bears cost of green energy 2022-08-08T04:00:00Z In 2010, Congress required companies to disclose the origin of so-called conflict minerals — tantalum, tin, gold and tungsten. ‘The Sacrifice Zone’: Myanmar bears cost of green energy 2022-08-08T04:00:00Z For instance, according to Securities and Exchange Commission filings, Apple is supplied by 10 smelters in Russia, producing gold, tungsten and tantalum used in products like the iPhone. Apple pauses all product sales in Russia, citing concern for Ukraine 2022-03-01T05:00:00Z The site has only trace amounts of radioactivity, Mr. Barnes said from Australia, but rich deposits of metals like tantalum, used in mobile phones, and zirconium, used in fuel cells and various kinds of electronics. The World Wants Greenland’s Minerals, but Greenlanders Are Wary 2021-10-01T04:00:00Z The spacecraft grabbed the material by firing a tantalum metal bullet into the surface and letting debris float up a collection tube under the low gravity. Hayabusa-2: Pieces of an asteroid found inside space capsule 2020-12-15T05:00:00Z Ando et al. produced an artificial film called a superlattice that is composed of stacked alternating layers of niobium, vanadium and tantalum. One-way supercurrent achieved in an electrically polar film 2020-08-18T04:00:00Z The powder is a byproduct from tantalum and niobium mining by Estonian company Silmet, which contains uranium. In Utah, a debate stirs over Estonian radioactive waste 2020-07-16T04:00:00Z The minerals involved are tin, tantalum, tungsten and gold. Exclusive: London Metal Exchange to delay ban on tainted metal... 2019-09-18T04:00:00Z Scientists estimate that indium and tantalum mines, among others, could run out within a century. Millions of old gadgets 'stockpiled in drawers' 2019-08-20T04:00:00Z As the craft touched down, it fired a tantalum bullet into the surface, likely kicking dust and rock fragments into a collection horn. In a first, a Japanese spacecraft appears to have collected samples from inside an asteroid 2019-07-11T04:00:00Z Meanwhile JX, which bought a German maker of tantalum and niobium products last year, is studying the possible acquisition of stakes in mines producing the two rare metals, he said. Japan's JX Nippon Mining seeks pot of gold in high-tech chips,... 2019-07-03T04:00:00Z In February, Hayabusa2 briefly landed on Ryugu and fired a tantalum pellet into the surface that likely knocked about 10 grams of rock fragments into a collection horn. A Japanese spacecraft may have just blown a crater in a distant asteroid 2019-04-05T04:00:00Z Then, on touchdown, a 5g projectile made of the metal tantalum is fired into the rocky surface. Movie shows moment of asteroid landing 2019-03-05T05:00:00Z Most of us will not have heard of tantalum, but it's a highly corrosion-resistant metal that is "perfect for small electronic devices like our phones", explained Dr Ratcliffe. Millions of old gadgets 'stockpiled in drawers' 2019-08-20T04:00:00Z According to Jaxa, the results of the test exceeded expectations, with the tantalum projectile yielding fragments of rock in size ranges that should easily pass through the sampler horn. Japan probe set to 'bite an asteroid' 2019-02-21T05:00:00Z Congo produces some two-thirds of the world’s cobalt, a mineral used in the production of lithium-ion batteries that power laptops and electric cars, and coltan, copper, tantalum and tin, all used in modern electronics. Congo Keeps Voters in the Dark About Election Results 2019-01-02T05:00:00Z Power Resources Group’s clients include Kemet, which produces tantalum capacitors for mobile phones. Wooing investors, Rwanda hosts first tantalum-tracking blockchain 2018-10-17T04:00:00Z However, some e-waste mining projects, such as the RecEOL initiative recently announced in Ireland, can recover iridium from scrap products, along with other rare metals such as tantalum. Mining for precious metals without a pick-axe in sight 2018-07-05T04:00:00Z Technology-critical elements include tantalum, gallium, germanium, indium, niobium, tellurium, thallium and other scarce metals. Risks from technology-critical metals after extraction 2018-05-22T04:00:00Z This device depended on thin oxide films covering its tantalum electrodes, which for Ovshinsky were the analogue of nerve cell membranes. The Most Important Inventor You've Never Heard Of 2018-05-17T04:00:00Z Wartime work camps in, say, the Democratic Republic of the Congo supply the rare-earth metals such as tantalum that power the physical infrastructure behind the virtual economy. How the chicken nugget became the true symbol of our era 2018-05-08T04:00:00Z Its mining industry - which also produces diamond, tantalum, tin and gold - is the country's largest source of export income. DR Congo upsets big miners with new law 2018-03-10T05:00:00Z It also raises taxes on other metals such as copper, tantalum and gold. Mining Giants Face Blow From World’s No. 1 Cobalt Producer 2018-03-08T05:00:00Z But this may be only a temporary reprieve for the area, which is thought to contain deposits of gold, copper, tantalum, iron ore, nickel and manganese. Brazilian court blocks abolition of vast Amazon reserve 2017-08-30T04:00:00Z Electrons moving through a crystal usually scatter when they hit an impurity, which slows their progress, but the topological effects in Hasan’s tantalum arsenide crystals allow electrons to travel unimpeded. The strange topology that is reshaping physics 2017-07-18T04:00:00Z These rare earth metals along with minor metals such as lithium and tantalum are now just as important as the traditional base metals and precious metals. Could you cope with smartphone rationing? - BBC News 2017-06-12T04:00:00Z The conflict minerals disclosure rule requires companies to tell investors whether their products contain tin, tantalum, tungsten or gold that is mined from The Democratic Republic of the Congo. SEC Says Conflict Minerals, Pay Ratio Rules Remain In Force 2017-02-24T05:00:00Z It requires companies to check whether they are funding conflict or human rights abuses through their purchases of minerals, including tin, tantalum, tungsten and gold. Proposed Trump executive order would allow US firms to sell 'conflict minerals' 2017-02-08T05:00:00Z The best known effort to regulate mining is the U.S. law regarding four “conflict minerals” from the Congo region: tin, tungsten, tantalum and gold. Tesla aims to sustain purity of car batteries, but can any company be sure? 2016-12-30T05:00:00Z A 2010 law aimed at stemming the flow of money to Congo's murderous militias requires U.S. companies to attempt to trace the sources of their tin, tungsten, tantalum and gold. State Department signals interest in how tech companies address abuses in cobalt supply chain 2016-12-23T05:00:00Z The EICC said companies need to expand scrutiny of their supply chains beyond the traditional four “conflict” minerals covered by U.S. legislation — tin, tungsten, tantalum and gold. Tech giants pledge to keep children out of cobalt mines that supply smartphone and electric-car batteries 2016-12-20T05:00:00Z Legislators hoped that by requiring U.S. companies to disclose purchases of tantalum, tin, tungsten and gold, the militias’ funding would dry up. How Dodd-Frank Led to More Mayhem in Africa 2016-11-13T05:00:00Z Conditions are improving for miners who dig the ore that's processed into tin, tungsten and tantalum for smartphones and other electronics, though some still face interference from armed groups. Report: Gunmen still control metals mined for modern gadgets 2016-10-25T04:00:00Z Conditions are improving for miners who dig the ore that’s processed into tin, tungsten and tantalum for smartphones and other electronics, though some still face interference from armed groups. Report: Gunmen still control metals mined for modern gadgets 2016-10-24T04:00:00Z A 2010 U.S. law requires American companies to attempt to verify that any tin, tungsten, tantalum and gold they use is obtained from mines free of militia control in the Congo region. The cobalt pipeline: From dangerous tunnels in Congo to consumers’ mobile tech 2016-09-30T04:00:00Z Eastern Congo is an important source of minerals used in electronic devices like smartphones, but most people in the United States had never even heard of tantalum, much less considered where it originated. Why Some Wars (Like Syria’s) Get More Attention Than Others (Like Yemen’s) 2016-10-01T04:00:00Z Companies avoided the extra costs and red tape by boycotting tantalum, tin and tungsten mined in the Congo. How Dodd-Frank Led to More Mayhem in Africa 2016-11-13T05:00:00Z One section of the law requires corporations to file annual reports showing what they've done to determine if they're using tin, tungsten, tantalum or gold from Congo or neighboring countries. Report: Gunmen still control metals mined for modern gadgets 2016-10-25T04:00:00Z One section of the law requires corporations to file annual reports showing what they’ve done to determine if they’re using tin, tungsten, tantalum or gold from Congo or neighboring countries. Report: Gunmen still control metals mined for modern gadgets 2016-10-24T04:00:00Z Congo’s tin, tantalum and tungsten are used in electronics around the world. The richest, riskiest tin mine on Earth 2016-08-25T04:00:00Z The facility just outside Albany remains a major refiner of zirconium, used in fuel assemblies for nuclear reactors, as well as other exotic metals such as hafnium, niobium, tantalum and vanadium. Man waiting for late father’s Wah Chang compensation 2016-08-08T04:00:00Z U.S.-listed companies are required to investigate their supply chain for the presence tin, tantalum, tungsten and gold, under a rule stemming from the 2010 Dodd-Frank Act. Most companies failing to dig up conflict-mineral information 2016-07-30T04:00:00Z About 40 minerals go into a phone, but four in particular are precious and found in mines in war-torn regions—tin, tungsten, tantalum and gold. How Was Your Smartphone Made? Nobody Really Knows 2016-07-06T04:00:00Z High-resolution scanning tunneling spectroscopy reveals the connection between the surface and bulk states in tantalum arsenide. Quasiparticle interference of the Fermi arcs and surface-bulk connectivity of a Weyl semimetal | Science 2016-03-10T05:00:00Z To create their photonic crystals, the researchers started with millimeter thick sheets of glass and deposited 90 alternating layers of tantalum oxide and silicon dioxide. How to get that old-fashioned lightbulb glow without wasting so much energy 2016-01-11T05:00:00Z In terms of natural resources, Congo, with its wealth of copper, diamonds, gold and tantalum — a vital component of your mobile phone — is one of the richest countries in Africa. For 40 Lucky Children, an Escape From Congo's Diamond Mines 2015-10-02T04:00:00Z The tin and tantalum are sourced from conflict-free mines in the Democratic Republic of Congo, and the company is currently trying to find equally ethical sources of gold and tungsten. Fairphone wants you to take apart your smartphone 2015-09-28T04:00:00Z Conflict minerals are tantalum, tungsten, tin or gold mined from ore, and extracted in Congo or nine surrounding countries, including Angola, Rwanda and Sudan. Companies Struggle to Comply With Conflict Minerals Rule 2015-09-07T04:00:00Z High-resolution scanning tunneling spectroscopy reveals the connection between the surface and bulk states in tantalum arsenide. Quasiparticle interference of the Fermi arcs and surface-bulk connectivity of a Weyl semimetal | Science 2016-03-10T05:00:00Z “Conflict minerals” include tin, tantalum, tungsten and gold originating from the Democratic Republic of the Congo. U.S. Firms Struggle to Trace ‘Conflict Minerals’ 2015-08-03T04:00:00Z And that led me onto tin, tantalum, tungsten and other metals that we use in our phones and our cameras, and I started to work with the Enough Project to try to raise awareness. Marcus Bleasdale: When Photography Campaigns for Change 2015-04-30T04:00:00Z The 2010 Dodd-Frank financial overhaul required manufacturers to determine whether any gold, tin, tungsten or tantalum, a metal used in electronics, in their products came from the Democratic Republic of Congo. Survey Says Companies Not Meeting Minerals Rule 2015-04-22T04:00:00Z In smaller markets we might use the Metal Bulletin prices for tungsten or tantalum say. London Gold, Silver And Other Benchmarks To Get Libor Style Regulation 2014-09-28T04:00:00Z And that State Department official certainly didn’t: the major suppliers of “coltan” to the tantalum industry are Canada, Brazil and Australia, with no sign of any slave labour at all. What On Earth Is Slaveryfootprint.org Talking About Here? 2014-06-27T04:00:00Z Securities and Exchange Commission whether any tin, tantalum, tungsten or gold, in their supply chains is connected to violent militia groups in the Democratic Republic of the Congo. U.S. Firms Struggle to Trace ‘Conflict Minerals’ 2015-08-03T04:00:00Z At the simplest level, the memristor consists of a grid of wires with a stack of thin layers of materials such as tantalum oxide at each intersection. With 'The Machine,' HP May Have Invented a New Kind of Computer 2014-06-11T04:00:00Z Tungsten, tin, tantalum and gold—products common in electronics and known collectively as “3TG”—are mined heavily in the Democratic Republic of the Congo and other central African countries. There May Be Conflict Minerals in Your Smartphone 2014-06-03T04:00:00Z The term applies to raw materials, such as gold, tungsten, tantalum and tin, gathered by miners controlled by violent militia groups. 'Conflict' deadline looms for firms 2014-05-30T04:00:00Z The company also said its supply of tantalum, which is used to create capacitors, was entirely conflict-free. Apple issues first conflict minerals report, says majority of suppliers are in the clear 2014-05-29T04:00:00Z Twelve percent of the world’s supply of tantalum stems from miners in the DRC, according to the U.S. U.S. Firms Struggle to Trace ‘Conflict Minerals’ 2015-08-03T04:00:00Z In August 2012 the Securities and Exchange Commission began requiring firms to annually disclose the sources of the gold, tin, tungsten and tantalum used in their products. Could Your Texts, Tweets and Selfies Be Funding War in Africa? 2014-03-25T12:00:00Z No one is keen on abandoning the region entirely—despite raised awareness of conflict minerals, the Democratic Republic of the Congo’s share of tantalum production actually increased in 2013, according to the Wall Street Journal. There May Be Conflict Minerals in Your Smartphone 2014-06-03T04:00:00Z In its eighth annual supply-chain report, Apple also said the metal tantalum, an essential component in many electronic products, had not been sourced from war zones. Apple supplier review uncovers fewer child labor cases 2014-02-13T13:46:56Z Most electronic devices contain either gold, tantalum, tin or tungsten. Apple in conflict mineral crackdown 2014-02-13T13:20:01Z But metals such as tantalum, gallium, germanium and rare-earth elements are oxidized and effectively lost in the smelter slag. Resources: Track flows to manage technology-metal supply 2013-12-31T14:20:37.117Z You assume that if you need something like tantalum you just get it. The numbers of the year 2013 2013-12-31T00:05:43Z These high-strength components are typically built from expensive, exotic metals such as titanium, tantalum and vanadium. 3D printing 'entering the metal age' 2013-10-15T10:22:31Z Further up the supply chain, companies must procure essential metals such as tantalum, sometimes known as 'conflict minerals' due to their sale by armed groups in the Democratic Republic of Congo, Angola and South Sudan. Apple supplier review uncovers fewer child labor cases 2014-02-13T13:46:56Z Like gold prospectors, the men swish watery red mud around a flat wooden pan until pebbles containing a metal called tantalum appear. Tungsten: From the FARC’s mine in Colombia to global supply lines? 2013-08-16T15:41:53Z Among them are metals critical to the manufacture of electronic gadgets, without which no smartphone would exist: tantalum, tungsten, tin and gold. My search for a smartphone that is not soaked in blood 2013-03-11T20:15:01Z And that is what Metalysis is doing in its new tantalum factory, and what it hopes to do for titanium and the rest. Manufacturing metals: A tantalising prospect 2013-02-14T16:06:18Z The EU sees "especially strong potential" in Greenland's deposits of niobium, platinum, rare earths and tantalum, among the elements on an EU "critical raw materials" list. Greenland defiant on rare earths 2013-01-15T13:38:48Z Apple said its suppliers did not procure tantalum from any third-party providers linked to armed groups in various warring African countries. Apple supplier review uncovers fewer child labor cases 2014-02-13T13:46:56Z U.N. experts say the rebellion is partly funded by traders in Rwanda who are profiting from tin, tungsten and tantalum smuggled across the border from mines in eastern Congo. U.N. says Congo army, rebels have committed rights abuses 2012-12-07T19:25:42Z Of all the manufacturers, Nokia appears to have gone furthest to remove illegally mined tantalum from its supply chain. My search for a smartphone that is not soaked in blood 2013-03-11T20:15:01Z Now, the founders of Metalysis, a small British firm, hope to do much the same with tantalum, titanium and a host of other recherché and expensive metallic elements including neodymium, tungsten and vanadium. Manufacturing metals: A tantalising prospect 2013-02-14T16:06:18Z U.N. experts say the rebellion is partly funded by traders in Rwanda who are profiting from tin, tungsten and tantalum smuggled across the border from mines in the eastern Congo. Congo accuses Rwanda of shielding alleged war criminal 2012-11-28T21:22:31Z After gold, tantalum is the next most sought after mineral in Ethiopia. Gold mining promises big boost for Ethiopia's development 2012-08-30T11:14:45Z The "blood minerals" provisions say U.S.-listed firms that source gold, tungsten, tantalum and tin from Congo or its neighbors must assure regulators they are not funding conflict in that war-torn country. U.S. to clarify rules on oil, mining payments abroad 2012-08-20T17:09:52Z Since 2001 – long before most other companies began to take an interest – it has tried to remove illegally mined tantalum from its supply chain. My search for a smartphone that is not soaked in blood 2013-03-11T20:15:01Z The Enough Project said the armed groups in eastern Congo were still generating income by smuggling tantalum, tin and tungsten through Rwanda. U.S. rules denting Congo rebels' mineral profits: study 2012-08-07T23:01:11Z The act says U.S.-listed firms that source gold, tungsten, tantalum and tin from Congo or its neighbors must assure regulators they are not funding conflict. Congo unrest threatens push to curb conflict minerals trade 2012-07-18T08:00:22Z Much of the violence has been financed with profits from the mining of metals such as tin, coltan, tantalum and gold - all used in electronic appliances. DR Congo mining's reputation in tatters 2012-05-14T23:00:38Z Should the disclosure requirement be limited to tantalum, tin, tungsten and gold? SEC struggles to write ?conflict minerals? regulations for companies 2011-10-19T00:21:28Z The rule, which was tucked into the legislation at the last minute, will require companies to disclose whether they use tantalum, tin, gold or tungsten from the war-torn Democratic Republic of the Congo. SEC wrestling with "conflict minerals" disclosure 2011-10-16T15:44:42Z Securities and Exchange Commission to write rules forcing companies to disclose whether they use minerals such as tantalum, tin, gold or tungsten from Congo. U.S. buyers shun "conflict minerals" in Congo's east 2011-10-04T09:32:23Z Colombia may hold reserves of coltan, an ore containing tantalum used in mobile phones, in its eastern provinces, Rodado said in the Sept. Colombia May Auction Coal Rights to Lure Investors, Find Coltan 2011-09-05T15:33:23Z Global Advanced Metals supplies tantalum used in iPods and BlackBerry smart phones. UPDATE 1-Cabot to sell supermetals business for $400 mln 2011-08-25T13:04:49Z The government is preparing a decree to stop illegal miners exploiting deposits of gold and coltan, an ore containing tantalum, used in mobile phones and video-game consoles, he said. Chavez Orders Gold Repatriation, Will Nationalize Industry 2011-08-17T22:35:01Z Chavez, speaking on state television today, said he’s preparing a decree increasing government control to stop illegal miners exploiting deposits of gold and coltan, an ore containing tantalum, used in mobile phones and video-game consoles. Venezuela’s Chavez to Nationalize Gold Mines Held by ‘Mafia’ 2011-08-17T19:01:03Z Chavez, speaking today on state television, said Venezuela can’t allow illegal miners to continue exploiting deposits rich in gold and coltan, an ore containing tantalum, which is used in mobile phones and video-game consoles. Venezuela’s Chavez Preparing to Take Over Gold Industry 2011-08-17T17:11:01Z One beneficiary of the Dodd-Frank rule may be Australian miner Global Advanced Metals, which reopened a tantalum mine this year, says Chief Executive Officer Bryan Ellis. A Rule Aimed at Warlords Upends African Mines 2011-08-04T20:45:29Z That is possible because this part of the transistor is made of tantalum pentoxide, a material whose atoms are arranged in a lattice which contains holes large enough for copper atoms to squeeze through. New transistors: Mechanical advantage 2011-07-14T11:01:07Z Mr. McDermott traced much of the suffering to rebel soldiers who sold tantalum and other minerals to finance their war. DealBook: Unearthing Exotic Provisions Buried in Dodd-Frank 2011-07-13T17:22:07Z The researchers begin with tantalum pentoxide, but deposit the two layers using different deposition processes creating a multilayered thin film. Mantis Shrimp Eye Could Improve HD CDs, DVDs 2011-06-27T15:22:00Z The substance is tantalum, an ingredient in components that are a mainstay of devices like smartphones, digital tablets and personal computers. New U.S. Law Pressures Congo's Mines 2011-04-26T23:01:45Z Other materials have been used, such as zirconium, yttrium, and thorium oxides, and osmium and tantalum among the metals, but they have been displaced entirely by the materials mentioned above. The New Gresham Encyclopedia Volume 4, Part 2: Ebert to Estremadura 2011-04-14T02:00:56.200Z Under the SEC's proposal, companies annually reveal whether they are sourcing tantalum, tin, gold and tungsten from the war-torn region. Gold mine group opposes planned U.S. disclosure rule 2011-03-02T20:48:03Z The various improvements in electric illuminants, such as the Nernst oxide lamp, the tantalum and osmium incandescent lamps, and improved forms of arc lamp, enclosed, inverted and flame arcs, are described under Lighting: Electric. Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 2 "Ehud" to "Electroscope" 2011-01-29T03:00:23.777Z It also incorrectly stated that tantalum is a mineral. Minerals found in consumer electronic devices help finance civil war in Congo 2010-12-13T23:21:06Z While tech products typically contain only trace quantities of tantalum, companies in the technology industry are its biggest buyers. New U.S. Law Pressures Congo's Mines 2011-04-26T23:01:45Z Both the tin and the tantalum are contributing their part to making my life easier and my work more effective. The true cost of your new Christmas laptop? Ask the eastern Congolese 2010-12-12T21:00:00Z There are no simple solutions to the ongoing crisis in Congo, but Shannon has concentrated on embarrassing electronics makers, because they use parts that may contain minerals like tantalum from the area. | Rwanda ? Congo ? Nepal: D.I.Y. Foreign-Aid Revolution 2010-10-23T18:30:00Z It is short for "tantalum alloy", used in its first products. Elite audio firm Arcam targets iPods ? and goes for volume 2010-10-09T23:04:00Z Nor are diamonds the only conflict resource: minerals like tantalum, tungsten, tin, and gold — crucial for cell phones — are often smuggled out of war zones like eastern Congo. Naomi Campbell Brings Star Power to a War Crimes Trial 2010-08-05T16:05:00Z Mining remains a key source of income for thousands there—much of its tantalum and tin is mined by individuals who sell to dealers that trade with smelters across the globe. New U.S. Law Pressures Congo's Mines 2011-04-26T23:01:45Z At issue are three industrial metals -- tin, tantalum and tungsten -- and gold. Gadget Makers Forced to Look at Links to Congo War 2010-07-26T14:27:00Z It applies not only to electronics companies, which are major users of Congolese tantalum, but also to all publicly traded U.S. firms that use tin and gold. U.S. financial reform bill also targets 'conflict minerals' from Congo 2010-07-21T04:00:00Z Of 41 minerals and metals it analyzed, the commission identified these 14 as short in supply: antimony, beryllium, cobalt, fluorspar, gallium, indium, germanium, graphite, magnesium, niobium, platinum group metals, rare earths, tantalum and tungsten. Europe Sounds Alarm on Minerals Shortage 2010-06-16T19:03:00Z If the first figure of the last pair was assumed to be a null, the word was the symbol for tantalum: "Ta." The Caves of Fear The main tantalum and tin mines in Congo are owned by individuals or independent mining groups, and rebels often take over the mines. New U.S. Law Pressures Congo's Mines 2011-04-26T23:01:45Z The figure for tantalum ore, a rarer mineral, is higher, but the main sources for world supply are in Brazil and Australia. Gadget Makers Forced to Look at Links to Congo War 2010-07-26T14:27:00Z Congolese activists, U.N. experts and nongovernmental groups have become increasingly concerned that armed Congolese groups are financing themselves with minerals such as gold and the "three T's" -- tin, tungsten and tantalum. U.S. financial reform bill also targets 'conflict minerals' from Congo 2010-07-21T04:00:00Z Afghanistan, antimony, beryllium, , , cobalt, Democratic Republic of Congo, fluorspar, gallium, germanium, graphite, indium, magnesium, metals, minerals, niobium, platinum group metals, rare earths, Russia, tantalum, tungsten U.N. Europe Sounds Alarm on Minerals Shortage 2010-06-16T19:03:00Z Specimens in which the iron is largely replaced by manganese are known as manganocolumbite or manganotantalite, according as they contain more niobium or more tantalum. Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 6 "Cockaigne" to "Columbus, Christopher" A civil war in the Congo, the world's third-largest producer of tantalum, ended in 2003, but violence in the eastern part of the country continues. New U.S. Law Pressures Congo's Mines 2011-04-26T23:01:45Z Two years ago, chip maker Intel Corp. started to alert its tantalum smelters, who turn the ore into the metal, that they will have to start certifying that their ores don't come from ''conflict mines.'' Gadget Makers Forced to Look at Links to Congo War 2010-07-26T14:27:00Z Congo is the source for an estimated one-fifth of the world's tantalum, as well as smaller percentages of the other three minerals. U.S. financial reform bill also targets 'conflict minerals' from Congo 2010-07-21T04:00:00Z Chemically related to vanadium are the two elements tantalum and columbium or niobium. Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1 "Châtelet" to "Chicago" It is beyond his province to determine whether carbon should be replaced by tantalum, osmium or tungsten to get higher efficiency, but he must understand the effects of these lights and prescribe accordingly. Color Value Some metals, as for instance, osmium, tantalum, thorium, and others, have been used, and others, also, with great success, so that the march of improvements is now going forward with rapid strides. Electricity for Boys There is no tantalum on Mars except a little scattered through tons of rock. Giants on the Earth The new law requires American companies to submit an annual report to the Securities and Exchange Commission disclosing whether their products contain gold, tin, tungsten or tantalum from Congo or adjacent countries. U.S. financial reform bill also targets 'conflict minerals' from Congo 2010-07-21T04:00:00Z Just to make sure of cleaning up the last infinitesimal traces, though, I'm going to flash a getter charge of tantalum in it. Skylark Three I brought along a piece of platinum from the power plant, and something that I think is tantalum from Barkovis' description of it. Spacehounds of IPC The oxide of tantalum dissolves in the bead, but gives no colour. A Text-book of Assaying: For the Use of Those Connected with Mines. Owing to the low electrical resistance of tantalum, a filament in order to operate satisfactorily on a standard voltage must be long and thin. Artificial Light Its Influence upon Civilization The first metallic filament used in the electric light on a commercial scale was made of tantalum, the metal of Tantalus. Creative Chemistry Descriptive of Recent Achievements in the Chemical Industries Certain compounds of tin-oxides, particularly if they contain tantalum, are by fusion with carbonate of soda reduced with difficulty; but by the addition of some borax, the reduction to the metallic state is easily effected. A System of Instruction in the Practical Use of the Blowpipe Being A Graduated Course Of Analysis For The Use Of Students And All Those Engaged In The Examination Of Metallic Combinations "How are you going to separate out the tantalum and the others you want from the ones that you don't want?" Spacehounds of IPC The residue may consist of unremoved silica, and oxides of tantalum, niobium, and, perhaps, chromium. A Text-book of Assaying: For the Use of Those Connected with Mines. The tantalum filament was quickly followed by osmium and by tungsten in this country. Artificial Light Its Influence upon Civilization Columbium is a metal closely resembling tantalum and tantalum found a use as electric light filaments. Creative Chemistry Descriptive of Recent Achievements in the Chemical Industries Iridium, osmium, platinum, ruthenium, tantalum, thorium, tungsten, uranium. Scientific American Supplement, No. 799, April 25, 1891 Platinum melts somewhere around seventeen-fifty, tantalum about twenty-nine hundred, and tungsten not until 'way up around thirty-three, or four hundred—and that, by the way, means lots of grief. Spacehounds of IPC During the last four or five years lamps with filaments made from tantalum and tungsten have been produced and placed on the market with great success, and are now largely used. Edison, His Life and Inventions The tantalum lamp had no opportunity to become established, because the tungsten lamp followed its appearance very closely. Artificial Light Its Influence upon Civilization |
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英语例句辞典收录了117811条英语例句在线翻译词条，基本涵盖了全部常用单词及词组的例句翻译及用法，是英语学习的有利工具。