The Tungsten series was Palm, Inc. 's line of business-class Palm OS -based PDAs .
86-574: The Tungsten series was introduced in October 2002, created as a "prosumer" line priced at $ 199 to $ 300 to compete with the popular Sony Clie and Windows Mobile PDAs. The first device in the line is the Tungsten T, making it the first Palm PDA to be labeled with a letter rather than a number and to run Palm OS 5. All of the Tungsten PDAs have a few attributes in common: All models except
172-449: A Texas Instruments OMAP (ARM) 126 MHz processor, a 2 + 1 ⁄ 8 -by- 2 + 1 ⁄ 8 -inch (54 mm × 54 mm) transreflective TFT screen, and ran Palm OS 5.2.1. It is 4.5 by 3.1 by 0.5 in (114 by 79 by 13 mm), and weighs 4.6 ounces (130 g). It had a standard 3.5 mm headphone jack and a speaker in back and used a mini USB connector not supported by most dock accessories. At introduction, it
258-425: A body-centered cubic structure and is the more stable form. The structure of the β phase is called A15 cubic ; it is metastable , but can coexist with the α phase at ambient conditions owing to non-equilibrium synthesis or stabilization by impurities. Contrary to the α phase which crystallizes in isometric grains, the β form exhibits a columnar habit . The α phase has one third of the electrical resistivity and
344-437: A sextuple bond between tungsten atoms — the highest known bond order among stable atoms. In 1781, Carl Wilhelm Scheele discovered that a new acid , tungstic acid , could be made from scheelite (at the time called tungsten). Scheele and Torbern Bergman suggested that it might be possible to obtain a new metal by reducing this acid. In 1783, José and Fausto Elhuyar found an acid made from wolframite that
430-441: A 900 mAh capacity battery but third-party 1100 mAh or 1150 mAh LI-poly batteries of the same physical dimensions were available. Tungsten models used a five-way navigator pad, in the shape of a rounded rectangle, circle, or oval and had four buttons for built-in applications . The Palm Universal Connector is used by the Tungsten T, Tungsten T2, Tungsten T3, Tungsten C, Tungsten W, for cradles and accessories, while
516-658: A SD card which would then switch the PDA back on. In some countries, including Australia, the Tungsten T5 was withdrawn early since the Palm TX offered more advanced, built-in WiFi support, instead of requiring the optional Palm Wi-Fi Card in its one and only SD slot as many other non-Palm PDAs on the market at the time came standard with built-in WiFi. The Tungsten W (known as the i710 during its development period, and X420 at
602-501: A US court rejected General Electric 's attempt to patent it, overturning U.S. patent 1,082,933 granted in 1913 to William D. Coolidge . It is suggested that remnants of wolfram have been found in what may have been the garden of the astronomer/alchemist Tycho Brahe The name tungsten (which means ' heavy stone ' in Swedish and was the old Swedish name for the mineral scheelite and other minerals of similar density)
688-568: A colorless gas. At around 250 °C it will react with chlorine or bromine, and under certain hot conditions will react with iodine. Finely divided tungsten is pyrophoric . The most common formal oxidation state of tungsten is +6, but it exhibits all oxidation states from −2 to +6. Tungsten typically combines with oxygen to form the yellow tungstic oxide , WO 3 , which dissolves in aqueous alkaline solutions to form tungstate ions, WO 4 . Tungsten carbides (W 2 C and WC) are produced by heating powdered tungsten with carbon. W 2 C
774-418: A combination of the Tungsten E and Tungsten T3. It was the first and only Tungsten to use a 416 MHz Intel XScale PXA270 processor. It had a 320×480 TFT 16-bit Color Screen with a virtual input area. It retained the shape of the Tungsten E, but was taller, instead of the sliding bodies of the previous Tungsten T-series handhelds. The Tungsten T5 was the first Palm PDA to have a 320×480 pixel screen without
860-426: A different atom such as phosphorus in place of the two central hydrogens in metatungstate produces a wide variety of heteropoly acids, such as phosphotungstic acid H 3 PW 12 O 40 . Tungsten trioxide can form intercalation compounds with alkali metals. These are known as bronzes ; an example is sodium tungsten bronze . In gaseous form, tungsten forms the diatomic species W 2 . These molecules feature
946-453: A digital music player when used with a Secure Digital (SD) flash memory card. The T3 had a bigger, non-round, 5-way navigation pad with the four application buttons placed around it in a circular fashion instead of in a row, breaking from Palm's traditional application button layout. Palm would return to its more traditional layout in the following Tungsten T5 and Palm TX . The T3 had a Green/Red LED indicator light, however Palm only used
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#17328017602691032-422: A half-life of (1.8 ± 0.2) × 10 years; on average, this yields about two alpha decays of W per gram of natural tungsten per year. This rate is equivalent to a specific activity of roughly 63 micro- becquerel per kilogram. This rate of decay is orders of magnitude lower than that observed in carbon or potassium as found on earth, which likewise contain small amounts of long-lived radioactive isotopes. Bismuth
1118-551: A high melting point , elemental tungsten is used in many high-temperature applications, such as incandescent light bulb , cathode-ray tube , and vacuum tube filaments, heating elements , and rocket engine nozzles. Its high melting point also makes tungsten suitable for aerospace and high-temperature uses such as electrical, heating, and welding applications, notably in the gas tungsten arc welding process (also called tungsten inert gas (TIG) welding). Athena Connector The Palm Multi-Connector (also Athena Connector )
1204-638: A much lower superconducting transition temperature T C relative to the β phase: ca. 0.015 K vs. 1–4 K; mixing the two phases allows obtaining intermediate T C values. The T C value can also be raised by alloying tungsten with another metal (e.g. 7.9 K for W- Tc ). Such tungsten alloys are sometimes used in low-temperature superconducting circuits. Naturally occurring tungsten consists of four stable isotopes ( W, W, W, and W) and one very long-lived radioisotope, W. Theoretically, all five can decay into isotopes of element 72 ( hafnium ) by alpha emission , but only W has been observed to do so, with
1290-412: A new status bar appeared at the bottom of screen, giving quick access to the time, system information, home, find, menu access, alerts, Bluetooth, full-screen writing, screen rotation, and what is shown in the input area. The Tungsten T3 came with RealPlayer for Palm OS Handhelds (called RealOne Player for Palm OS Handhelds at the time of its release) in addition to a 3.5 mm Stereo Jack, making it
1376-534: A range of oxidation states. Notable examples include the trigonal prismatic W(CH 3 ) 6 and octahedral W(CO) 6 . The world's reserves of tungsten are 3,200,000 tonnes; they are mostly located in China (1,800,000 t), Canada (290,000 t), Russia (160,000 t), Vietnam (95,000 t) and Bolivia . As of 2017, China, Vietnam and Russia are the leading suppliers with 79,000, 7,200 and 3,100 tonnes, respectively. Canada had ceased production in late 2015 due to
1462-487: A sharp blow. The hardness and heat resistance of tungsten can contribute to useful alloys . A good example is high-speed steel , which can contain as much as 18% tungsten. Tungsten's high melting point makes tungsten a good material for applications like rocket nozzles , for example in the UGM-27 Polaris submarine-launched ballistic missile . Tungsten alloys are used in a wide range of applications, including
1548-488: A shortage of tungsten used in the shell core, caused in part by the Wolfram Crisis , limited their use. Tungsten has also been used in dense inert metal explosives , which use it as dense powder to reduce collateral damage while increasing the lethality of explosives within a small radius. Tungsten(IV) sulfide is a high temperature lubricant and is a component of catalysts for hydrodesulfurization . MoS 2
1634-614: A slider mechanism as used in the Tungsten T3, T2, and T, though other brands have had sliderless HVGA displays for years. It was also the first to have 256 MB of memory (versus 64 MB in the Tungsten T3), with 161.2 MB configured as a Flash Drive - accessible to computers via the device's Drive Mode feature, 63.8 MB available for applications, and 31 MB reserved for the OS. This often resulted in some confusion as
1720-499: A tungsten bar with gold, which has been observed since the 1980s, or taking an existing gold bar, drilling holes, and replacing the removed gold with tungsten rods. The densities are not exactly the same, and other properties of gold and tungsten differ, but gold-plated tungsten will pass superficial tests. Gold-plated tungsten is available commercially from China (the main source of tungsten), both in jewelry and as bars. Because it retains its strength at high temperatures and has
1806-414: Is hypoallergenic , and is harder than gold alloys (though not as hard as tungsten carbide), making it useful for rings that will resist scratching, especially in designs with a brushed finish . Because the density is so similar to that of gold (tungsten is only 0.36% less dense), and its price of the order of one-thousandth, tungsten can also be used in counterfeiting of gold bars , such as by plating
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#17328017602691892-475: Is selective laser melting , which is a form of 3D printing and allows creating complex three-dimensional shapes. Tungsten is mainly used in the production of hard materials based on tungsten carbide (WC), one of the hardest carbides . WC is an efficient electrical conductor , but W 2 C is less so. WC is used to make wear-resistant abrasives , and "carbide" cutting tools such as knives, drills, circular saws , dies , milling and turning tools used by
1978-434: Is 114 by 79 by 15 millimeters (4.5 by 3.1 by 0.59 in) and weighs 133 grams (4.7 oz). It had a standard 3.5 mm headphone jack, a longer-lasting battery than the Tungsten E, had Bluetooth capability, and a single speaker on the back. Much like the Tungsten T5 and Treo 650 , it used non-volatile flash memory, this time in the form of Non-Volatile File System , meaning that the data would be preserved even if
2064-413: Is 4.0 inches (100 mm) tall, 4.8 inches (120 mm) tall with the slider extended, by 3.0 inches (76 mm) wide by 0.6 inches (15 mm) thick, and weighs 5.6 ounces (160 g). Its design set itself apart from other PDAs by having a sliding lower portion; the bottom third of the casing could be slid up and down to cover or reveal the touch-sensitive Graffiti writing area. At introduction, it
2150-400: Is a power, audio and data interface connector designed by Palm, Inc. The connector is used by: LifeDrive , Tungsten E2, Tungsten T5, Treo 650 , Treo 680 , Treo 700p , Treo 750 , Treo 755p , Palm TX , Palm Centro . Palm, Inc. has changed the connectors it uses over time: The Connector can be used to charge the device, transfer data to a computer, HotSync , and play audio. It
2236-648: Is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work into metal . However, pure single-crystalline tungsten is more ductile and can be cut with a hard-steel hacksaw . Tungsten occurs in many alloys, which have numerous applications, including incandescent light bulb filaments, X-ray tubes , electrodes in gas tungsten arc welding , superalloys , and radiation shielding . Tungsten's hardness and high density make it suitable for military applications in penetrating projectiles . Tungsten compounds are often used as industrial catalysts . Its largest use
2322-476: Is heated with hydrogen or carbon to produce powdered tungsten. Because of tungsten's high melting point, it is not commercially feasible to cast tungsten ingots . Instead, powdered tungsten is mixed with small amounts of powdered nickel or other metals, and sintered . During the sintering process, the nickel diffuses into the tungsten, producing an alloy. Tungsten can also be extracted by hydrogen reduction of WF 6 : or pyrolytic decomposition : Tungsten
2408-484: Is in tungsten carbide , a wear-resistant metal used in metalworking , mining , and construction . About 50% of tungsten is used in tungsten carbide, with the remaining major use being alloys and steels: less than 10% is used other compounds. Tungsten is the only metal in the third transition series that is known to occur in biomolecules , being found in a few species of bacteria and archaea . However, tungsten interferes with molybdenum and copper metabolism and
2494-642: Is more commonly used for such applications. Tungsten oxides are used in ceramic glazes and calcium / magnesium tungstates are used widely in fluorescent lighting . Crystal tungstates are used as scintillation detectors in nuclear physics and nuclear medicine . Other salts that contain tungsten are used in the chemical and tanning industries. Tungsten oxide (WO 3 ) is incorporated into selective catalytic reduction (SCR) catalysts found in coal-fired power plants. These catalysts convert nitrogen oxides ( NO x ) to nitrogen (N 2 ) and water (H 2 O) using ammonia (NH 3 ). The tungsten oxide helps with
2580-546: Is much like the Tungsten T model, PalmOne did not sell this model in some markets, such as mainland China or Brazil . The Tungsten T2 was discontinued in April 2004, having been succeeded by the Tungsten T3. The Tungsten T3 was the third T-Class Tungsten device, released in October 2003. It had 64 MB of memory (with 52 MB usable), a 400 MHz Intel PXA261 processor, a new 3.7-inch 320×480 transflective TFT LCD touch-screen, and ran Palm OS version 5.2.1. It
2666-498: Is not traded as a futures contract and cannot be tracked on exchanges like the London Metal Exchange . The tungsten industry often uses independent pricing references such as Argus Media or Metal Bulletin as a basis for contracts. The prices are usually quoted for tungsten concentrate or WO 3 . Approximately half of the tungsten is consumed for the production of hard materials – namely tungsten carbide – with
Palm Tungsten - Misplaced Pages Continue
2752-663: Is problematic even in depleted form, or where uranium's additional pyrophoric properties are not desired (for example, in ordinary small arms bullets designed to penetrate body armor). Similarly, tungsten alloys have also been used in shells , grenades , and missiles , to create supersonic shrapnel. Germany used tungsten during World War II to produce shells for anti-tank gun designs using the Gerlich squeeze bore principle to achieve very high muzzle velocity and enhanced armor penetration from comparatively small caliber and light weight field artillery. The weapons were highly effective but
2838-426: Is resistant to chemical attack, although it reacts strongly with chlorine to form tungsten hexachloride (WCl 6 ). In aqueous solution, tungstate gives the heteropoly acids and polyoxometalate anions under neutral and acidic conditions. As tungstate is progressively treated with acid, it first yields the soluble, metastable "paratungstate A" anion , W 7 O 24 , which over time converts to
2924-450: Is somewhat toxic to most forms of animal life. In its raw form, tungsten is a hard steel-grey metal that is often brittle and hard to work . Purified, monocrystalline tungsten retains its hardness (which exceeds that of many steels), and becomes malleable enough that it can be worked easily. It is worked by forging , drawing , or extruding but it is more commonly formed by sintering . Of all metals in pure form, tungsten has
3010-638: Is strictly regulated by the Chinese Government, which fights illegal mining and excessive pollution originating from mining and refining processes. There is a large deposit of tungsten ore on the edge of Dartmoor in the United Kingdom , which was exploited during World War I and World War II as the Hemerdon Mine . Following increases in tungsten prices, this mine was reactivated in 2014, but ceased activities in 2018. Within
3096-489: Is the new standard to replace the previous Palm Universal Connector , which performed similar functions but did not have an audio output capability. This port has also been used to connect to an external microphone or to GPS units The connector is divided in two sections: the longer one has thirteen pins numbered from right to left (5 to 17); the shorter one has three pins, on the left (3), top (2) and right (1). The cable shield connectors (4,18) are located on each side of
3182-544: Is used in English, French, and many other languages as the name of the element, but wolfram (or volfram ) is used in most European (especially Germanic and Slavic) languages and is derived from the mineral wolframite , which is the origin of the chemical symbol W . The name wolframite is derived from German wolf rahm ( ' wolf soot, wolf cream ' ), the name given to tungsten by Johan Gottschalk Wallerius in 1747. This, in turn, derives from Latin lupi spuma ,
3268-709: The Carrock mine from the German owned Cumbrian Mining Company and, during World War I , restrict German access elsewhere. In World War II , tungsten played a more significant role in background political dealings. Portugal, as the main European source of the element, was put under pressure from both sides , because of its deposits of wolframite ore at Panasqueira . Tungsten's desirable properties such as resistance to high temperatures, its hardness and density, and its strengthening of alloys made it an important raw material for
3354-599: The EU , the Austrian Felbertal scheelite deposit is one of the few producing tungsten mines. Portugal is one of Europe's main tungsten producers, with 121 kt of contained tungsten in mineral concentrates from 1910 to 2020, accounting for roughly 3.3% of the global production. Tungsten is considered to be a conflict mineral due to the unethical mining practices observed in the Democratic Republic of
3440-613: The Palm Universal Connector . The speed of the Bluetooth connection can only be set to a maximum of 128 kbit/s. At the time of its release, the Tungsten T5 (along with the Treo 650 ) was plagued with memory inefficiency problems, third-party application issues, and device driver crashes, due to the new Non-Volatile File System . The addition of NVFS however, brought the benefit of no longer losing all stored data in
3526-473: The Congo . South Korea's Sangdong mine , one of the world's largest tungsten mines with 7,890,000 tonnes of high-grade tungsten reportedly buried, was closed in 1994 due to low profitability but has since re-registered mining rights and is scheduled to resume activities in 2024. Tungsten is extracted from its ores in several stages. The ore is eventually converted to tungsten(VI) oxide (WO 3 ), which
Palm Tungsten - Misplaced Pages Continue
3612-652: The T3 still had a front-facing speaker, a microphone, a vibrating alarm feature, an indicator light, and all of their other features. Like the Tungsten E, the Tungsten T3 came with an enhanced PIM Suite which categorized all appointments and tasks on the Calendar (formerly Date Book) screen. The Enhanced PIM Software also featured an improved Task suite (formerly To Do List) which could categorize tasks by urgency, category, etc., and an improved Contacts (formerly Address) application with picture support and more fields. Furthermore,
3698-694: The Tungsten C, W, and E have built-in Bluetooth wireless capabilities, while the Tungsten C and TX feature built-in Wi-Fi connectivity. Furthermore, by using the optional Palm Wi-Fi Secure_Digital#SDIO_cards Card accessory, the T3, T5, and E2 can also gain Wi-Fi connectivity. With the exception of the Tungsten W, all Tungsten PDAs run Palm OS 5 "Garnet" on an ARM processor and have non-user-replaceable lithium-ion batteries. Some users replaced battery packs with third-party units. The T3, for example, shipped with
3784-435: The Tungsten C, except lacking the W's external antennae). Tungsten Tungsten (also called wolfram ) is a chemical element ; it has symbol W and atomic number 74. It is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a distinct element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite ,
3870-522: The Tungsten E uses a mini-USB connection; the Tungsten T5, Tungsten E2 and TX used an Athena Connector also known as the Palm Multi-Connector. All Tungsten handhelds come bundled with Dataviz's Documents To Go office suite and some version of Kinoma Player , with the exception of the Tungsten W. Palm's Tungsten E was the cheapest of the Tungsten series, and as such, has been one of the most successful. It has 32 megabytes of memory,
3956-511: The Tungsten T series' subsequent devices, the Tungsten T5 and the TX. It was superseded in April 2005, when palmOne released the Tungsten E2. The Tungsten E2 , introduced on April 13, 2005, replaced the similarly named Tungsten E, had 32 MB of memory (29.7 available), a 200 MHz Intel XScale processor, 320x320 Transflective TFT color display, and ran Palm OS Garnet v5.4.7. It
4042-475: The Tungsten T3 include it electronically damaging SD cards and its relatively low battery life (900 mA·h battery, larger display and processor clocked above most other Palm handhelds). Palm addressed the Secure Digital Card problem by releasing a Firmware Update. After the "SD Card Patch" was applied in early (by the user via a firmware patch ) and later (at the manufacturing stage) releases of
4128-406: The Tungsten T3, no other criticisms were known to have risen from the Tungsten T3's use. Shortly after the early 2005 release of the Tungsten T5, the Tungsten T3 was discontinued. Since then, no other Palm handhelds included a vibrating alarm, a slider to make the device smaller, or the Palm Universal Connector . The Tungsten T5 , introduced in October 2004 and now discontinued, was aesthetically
4214-417: The aerospace and automotive industries and radiation shielding. Superalloys containing tungsten, such as Hastelloy and Stellite , are used in turbine blades and wear-resistant parts and coatings. Tungsten's heat resistance makes it useful in arc welding applications when combined with another highly-conductive metal such as silver or copper. The silver or copper provides the necessary conductivity and
4300-458: The alphabet, such as the letters "t" and "k". Most all of the other letters required strokes different from those used in Graffiti 1. Palm's reasoning behind the slider was that users spent more time viewing data rather than entering it. Thus, they chose to hide the data entry medium while not in use to make a more compact device. The slider caused two problems with the Tungsten T. One drawback
4386-422: The arms industry, both as a constituent of weapons and equipment and employed in production itself, e.g., in tungsten carbide cutting tools for machining steel. Now tungsten is used in many more applications such as aircraft and motorsport ballast weights, darts, anti-vibration tooling, and sporting equipment. Tungsten is unique amongst the elements in that it has been the subject of patent proceedings. In 1928,
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#17328017602694472-522: The battery ran out. It used standard SD memory cards and was also compatible with the Palm Wi-Fi Card (sold separately). It used a standard Athena Connector port supported only by some then-newer accessories. When it was released, its retail price was US$ 249. In October 2005, the price was reduced to US$ 199. Unlike other models, the Find function was limited to only the first eight matches, and
4558-495: The bottom portion, with the five-way controller and four buttons, could slide shut, covering up the Graffiti writing area. This made it the smallest Palm PDA in height. The Tungsten T was the last Palm PDA to use the original Graffiti Version 1 handwriting recognition software. Because of a lawsuit by Xerox Corporation Palm Inc. was forced to discontinue Graffiti 1 and later Palm PDAs used Graffiti Version 2. The revised software required two separate strokes for entry of some letters of
4644-412: The calculator incorrectly found percentages at half their actual value, though this was fixed in units shipping after April 2006. The Tungsten E2 had the ability to use WiFi, but only by using an add-on SDIO card released by PalmOne , manufactured by SyChip . Encryption was restricted to primitive WEP security, and did not offer WPA or WPA2 . The maximum size SD card supported on the Tungsten E2
4730-448: The closure of its sole tungsten mine. Meanwhile, Vietnam had significantly increased its output in the 2010s, owing to the major optimization of its domestic refining operations, and overtook Russia and Bolivia. China remains the world's leader not only in production, but also in export and consumption of tungsten products. Tungsten production is gradually increasing outside China because of the rising demand. Meanwhile, its supply by China
4816-404: The density, tungsten is seen as an alternative (albeit more expensive) to lead fishing sinkers . Depleted uranium is also used for these purposes, due to similarly high density. Seventy-five-kg blocks of tungsten were used as "cruise balance mass devices" on the entry vehicle portion of the 2012 Mars Science Laboratory spacecraft. It is an ideal material to use as a dolly for riveting , where
4902-488: The element tungsten is not ferromagnetic (but iron is), when it is present in steel in these proportions, it stabilizes the martensite phase, which has greater ferromagnetism than the ferrite (iron) phase due to its greater resistance to magnetic domain wall motion . Tungsten, usually alloyed with nickel , iron , or cobalt to form heavy alloys, is used in kinetic energy penetrators as an alternative to depleted uranium , in applications where uranium's radioactivity
4988-469: The event of a complete battery drain. Tungsten T5 owners were encouraged to install the Tungsten T5 1.1 Update , which addressed the memory inefficiency issues alongside other operating system-level problems. The power button was prone to reliability issues causing it to become inoperative over time, requiring the user to either use a third-party app, rely on the PDA's other physical buttons or insert
5074-485: The green LED for most purposes, red only being used by certain third-party programs and libraries. The T3 also had the Palm Universal Connector and an included USB cradle. The cradle was used for both charging and synchronizing the Palm's data to a PC (With support included for Windows and Mac OS X , but with the pilot-link software, the unit synchronizes perfectly with a Unix operating system). Early criticisms of
5160-500: The high wear resistance and thermal conductivity of tungsten carbide improves the printing of abrasive filaments. Some string instrument strings incorporates tungsten. Tungsten is used as an absorber on the electron telescope on the Cosmic Ray System of the two Voyager spacecraft . Its density, similar to that of gold, allows tungsten to be used in jewelry as an alternative to gold or platinum . Metallic tungsten
5246-515: The highest melting point (3,422 °C, 6,192 °F), lowest vapor pressure (at temperatures above 1,650 °C, 3,000 °F), and the highest tensile strength . Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so it has no melting point. Moreover, tungsten's most stable crystal phase does not exhibit any high-pressure-induced structural transformations for pressures up to at least 364 gigapascals. Tungsten has
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#17328017602695332-499: The latter lending the element its alternative name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements, melting at 3,422 °C (6,192 °F; 3,695 K). It also has the highest boiling point , at 5,930 °C (10,706 °F; 6,203 K). Its density is 19.254 g/cm , comparable with that of uranium and gold , and much higher (about 1.7 times) than that of lead . Polycrystalline tungsten
5418-480: The less soluble "paratungstate B" anion, H 2 W 12 O 42 . Further acidification produces the very soluble metatungstate anion, H 2 W 12 O 40 , after which equilibrium is reached. The metatungstate ion exists as a symmetric cluster of twelve tungsten- oxygen octahedra known as the Keggin anion. Many other polyoxometalate anions exist as metastable species. The inclusion of
5504-402: The lowest coefficient of thermal expansion of any pure metal. The low thermal expansion and high melting point and tensile strength of tungsten originate from strong covalent bonds formed between tungsten atoms by the 5d electrons. Alloying small quantities of tungsten with steel greatly increases its toughness . Tungsten exists in two major crystalline forms: α and β. The former has
5590-540: The mass necessary for good results can be achieved in a compact bar. High-density alloys of tungsten with nickel, copper or iron are used in high-quality darts (to allow for a smaller diameter and thus tighter groupings) or for artificial flies (tungsten beads allow the fly to sink rapidly). Tungsten is also used as a heavy bolt to lower the rate of fire of the SWD M11/9 sub-machine gun from 1300 RPM to 700 RPM. Tungsten has seen use recently in nozzles for 3D printing ;
5676-446: The memory was not equally usable as in previous Palm PDAs. While the Tungsten T5 was meant to be a replacement for the Tungsten T3, it lacked several features from the Tungsten T3 such as a charge-indicator LED, a vibrating alarm, an included HotSync cradle, and built in microphone for voice memos. Furthermore, its speaker became rear-facing instead of front-facing and the PDA used the then-new Multi-Connector/Athena Connector instead of
5762-431: The metal matrix in place of cobalt because it takes a higher luster when polished. Sometimes manufacturers or retailers refer to tungsten carbide as a metal, but it is a ceramic . Because of tungsten carbide's hardness, rings made of this material are extremely abrasion resistant, and will hold a burnished finish longer than rings made of metallic tungsten. Tungsten carbide rings are brittle, however, and may crack under
5848-538: The metalworking, woodworking, mining , petroleum and construction industries. Carbide tooling is actually a ceramic/metal composite, where metallic cobalt acts as a binding (matrix) material to hold the WC particles in place. This type of industrial use accounts for about 60% of current tungsten consumption. The jewelry industry makes rings of sintered tungsten carbide , tungsten carbide/metal composites, and also metallic tungsten. WC/metal composite rings use nickel as
5934-483: The most stable being W ( t 1/2 6.4 minutes). Tungsten is a mostly non-reactive element: it does not react with water, is immune to attack by most acids and bases, and does not react with oxygen or air at room temperature. At elevated temperatures (i.e., when red-hot) it reacts with oxygen to form the trioxide compound tungsten(VI), WO 3 . It will, however, react directly with fluorine (F 2 ) at room temperature to form tungsten(VI) fluoride (WF 6 ),
6020-412: The most stable of which are W with a half-life of 121.2 days, W with a half-life of 75.1 days, W with a half-life of 69.4 days, W with a half-life of 21.6 days, and W with a half-life of 23.72 h. All of the remaining radioactive isotopes have half-lives of less than 3 hours, and most of these have half-lives below 8 minutes. Tungsten also has 11 meta states , with
6106-721: The name Georg Agricola used for the mineral in 1546, which translates into English as ' wolf's froth ' and is a reference to the large amounts of tin consumed by the mineral during its extraction, as though the mineral devoured it like a wolf. This naming follows a tradition of colorful names miners from the Ore Mountains would give various minerals, out of a superstition that certain ones that looked as if they contained then-known valuable metals but when extracted were somehow "hexed". Cobalt (cf. Kobold ), pitchblende (cf. German blenden for ' to blind, to deceive ' ) and nickel (cf. "Old Nick") derive their names from
6192-426: The pervasiveness of the chromium(III) compounds. The highest oxidation state is seen in tungsten(VI) oxide (WO 3 ). Tungsten(VI) oxide is soluble in aqueous base , forming tungstate (WO 4 ). This oxyanion condenses at lower pH values, forming polyoxotungstates . The broad range of oxidation states of tungsten is reflected in its various chlorides: Organotungsten compounds are numerous and also span
6278-619: The physical strength of the catalyst and extends catalyst life. Tungsten containing catalysts are promising for epoxidation, oxidation, and hydrogenolysis reactions. Tungsten heteropoly acids are key component of multifunctional catalysts. Tungstates can be used as photocatalyst, while the tungsten sulfide as electrocatalyst. Applications requiring its high density include weights, counterweights , ballast keels for yachts, tail ballast for commercial aircraft, rotor weights for civil and military helicopters, and as ballast in race cars for NASCAR and Formula One . Being slightly less than twice
6364-557: The prototype stage), was introduced in February 2003. The sole smartphone (PDA/ cellphone hybrid) in the Tungsten series, instead of running Palm OS 5 on an ARM -compatible processor, it used last-generation Palm OS 4 paired with a Motorola DragonBall processor that was typical of Palm OS 4 devices. It had a thumb-sized hard plastic keyboard, like the Treo 600 rather than the typical silkscreen Graffiti Writing Area found on most Palm handhelds. (This form factor would be reused in
6450-402: The remaining major use being in alloys and steels. Less than 10% is used in other chemical compounds . Because of the high ductile-brittle transition temperature of tungsten, its products are conventionally manufactured through powder metallurgy , spark plasma sintering , chemical vapor deposition , hot isostatic pressing , and thermoplastic routes. A more flexible manufacturing alternative
6536-1044: The same miners' idiom. Tungsten has thus far not been found in nature in its pure form. Instead, tungsten is found mainly in the minerals wolframite and scheelite . Wolframite is iron – manganese tungstate (Fe,Mn)WO 4 , a solid solution of the two minerals ferberite (FeWO 4 ) and hübnerite (MnWO 4 ), while scheelite is calcium tungstate (CaWO 4 ). Other tungsten minerals range in their level of abundance from moderate to very rare, and have almost no economic value. Tungsten forms chemical compounds in oxidation states from -II to VI. Higher oxidation states, always as oxides, are relevant to its terrestrial occurrence and its biological roles, mid-level oxidation states are often associated with metal clusters , and very low oxidation states are typically associated with CO complexes . The chemistries of tungsten and molybdenum show strong similarities to each other, as well as contrasts with their lighter congener, chromium . The relative rarity of tungsten(III), for example, contrasts with
6622-549: The thirteen pins. Pins 10 and 11 have TTL levels and cannot be directly connected to the RS-232 port. The Multi-Connector has received criticism from users who were familiar with previous connectors such as the Universal Connector. Users have been frustrated with the requirement to replace their Universal Connector cables, cradles, keyboards, sleds, and attachments as they have become incompatible. Another criticism
6708-441: The tungsten allows the welding rod to withstand the high temperatures of the arc welding environment. Quenched (martensitic) tungsten steel (approx. 5.5% to 7.0% W with 0.5% to 0.7% C) was used for making hard permanent magnets, due to its high remanence and coercivity , as noted by John Hopkinson (1849–1898) as early as 1886. The magnetic properties of a metal or an alloy are very sensitive to microstructure. For example, while
6794-696: Was 1 GB due to a software limitation. In order to read larger SD and SDHC cards an upgraded driver is required. The previous model ( Tungsten E ) had been reported to be capable of using 2 GB SD cards. The first Tungsten, the Tungsten T , introduced in November 2002 and known during development as the M550 , was the first model to use Palm OS 5. The Tungsten T was designed by Palm engineers based in Arlington Heights , Illinois . It had: It
6880-555: Was US$ 199. The Tungsten E, released in October 2003, was intended to replace the aging Palm m515 , one of the last holdouts from Palm's old product line. The Tungsten E, though, did not include a vibrating alarm and indicator light like the Palm m500 series had. Since it was released at the same time as the Tungsten T3, the Tungsten E included the T3's newer PIM apps and the enhanced "agenda view" for quick viewing of to-do items and upcoming calendar items. The Tungsten E's design influenced
6966-414: Was US$ 499. Many of the features in the Tungsten T were Palm firsts. It was the first Palm PDA to use a version of Palm OS 5 and an ARM processor, which meant that it had the software and processing power for high-quality real-time video playback and MP3 playback. It was also the first Palm PDA with a: The slider feature was unique. When open, the Tungsten T looked like a normal slate-shaped PDA, but
7052-490: Was identical to tungstic acid. Later that year, at the Royal Basque Society in the town of Bergara , Spain, the brothers succeeded in isolating tungsten by reduction of this acid with charcoal , and they are credited with the discovery of the element (they called it "wolfram" or "volfram"). The strategic value of tungsten came to notice in the early 20th century. British authorities acted in 1912 to free
7138-585: Was long thought to be non-radioactive, but Bi (its longest lived isotope) actually decays with a half life of 2.01 × 10 years or about a factor 10 slower than W . However, due to naturally occurring bismuth being 100% Bi , its specific activity is actually higher than that of natural tungsten at 3 milli-becquerel per kilogram. The other naturally occurring isotopes of tungsten have not been observed to decay, constraining their half-lives to be at least 4 × 10 years . Another 34 artificial radioisotopes of tungsten have been characterized,
7224-643: Was succeeded by the Tungsten T2. The Tungsten T2 , introduced in July 2003 for US$ 399, was simply a minor update to the Tungsten T, and had exactly the same form factor. (Save for the label and the T|T2's slightly lighter case color, they are superficially identical.) The memory was increased to 32 megabytes , the screen was replaced with a superior (backlight) TFT LCD of the same size and resolution, Palm OS upgraded to 5.2.1, Graffiti replaced with Graffiti2. Since it
7310-421: Was that the Tungsten T was known for its digitizer becoming miscalibrated after about one year of use and requiring further recalibration . A software patch issued by Palm helped with this problem. Another problem was that the ribbon cable between the mainboard and the digitizer connectors that tended to become loose over time, requiring disassembly to reconnect the ribbon cable for further use. The Tungsten T
7396-485: Was the last product designed by the Palm engineers in Arlington Heights. The T3 included Active Input Technology with Virtual Graffiti 2 , a virtual keyboard , and the typical Tungsten line slider. Along with many other additional features, the T3 was released with the same $ 399 retail price tag as the Tungsten T2 until the release of the Tungsten T5, when it was reduced to $ 349. Like the Tungsten T and T2,
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