Lead

Lead (/lɛd/) is a chemical element in the carbon group with symbol Pb (from Latin: plumbum) and atomic number 82. It is a soft, malleable and heavy post-transition metal. Freshly cut, solid lead has a bluish-white color that soon tarnishes to a dull grayish color when exposed to air; the liquid metal has shiny chrome-silver luster. Lead is the heaviest (has the highest atomic number) non-radioactive element (two radioactive elements, namely technetium and promethium, are lighter), although the next higher element, bismuth, has one isotope with a half-life that is so long (over one billion times the estimated age of the universe) that it can be considered stable. Lead's four stable isotopes each have 82 protons, a magic number in the nuclear shell model of atomic nuclei. The isotope lead-208 also has 126 neutrons, another magic number, and is hence double magic, a property that grants it enhanced stability: lead-208 is the heaviest known stable nuclide.

Lead is used in building construction, lead-acid batteries, bullets and shot, weights, as part of solders, pewters, fusible alloys, and as a radiation shield.

Cutoff (steam engine)

In a steam engine, cutoff is the point in the piston stroke at which the inlet valve is closed. On a steam locomotive, the cutoff is controlled by the reversing gear.

The point at which the inlet valve closes and stops the entry of steam into the cylinder from the boiler plays a crucial role in the control of a steam engine. Once the valve has closed, steam trapped in the cylinder expands adiabatically. The steam pressure drops as it expands. A late cutoff delivers full steam pressure to move the piston through its entire stroke, for maximum start-up forces. But, since there will still be unexploited pressure in the cylinder at the end of the stroke, this is achieved at the expense of engine efficiency. In this situation the steam will still have considerable pressure remaining when it is exhausted resulting in the characteristic “chuff chuff” sound of a steam engine. An early cutoff has greater thermodynamic efficiency but results in a lower Mean effective pressure so less average force on the piston and is used for running the engine at higher speeds. The steam engine is the only thermodynamic engine design that can provide its maximum torque at zero revolutions per minute.

Lead (electronics)

In electronics, a lead is an electrical connection consisting of a length of wire or metal pad (SMD) that comes from a device. Leads are used for physical support, to transfer power, to probe circuits (see multimeter), to transmit information, and sometimes as a heatsink. The tiny leads coming off through-hole components are also often called pins.

Many electrical components such as capacitors, resistors, and inductors have only two leads where some integrated circuits (ICs) can have several hundred leads to more than a thousand for the largest BGA devices. IC pins often either bend under the package body like a letter "J" (J-lead) or come out, down, and form a flat foot for securing to the board (S-lead or gull-lead).

Most kinds of integrated circuit packaging are made by placing the silicon chip on a lead frame, wire bonding the chip to the metal leads of that lead frame, and covering the chip with plastic. The metal leads protruding from the plastic are then either "cut long" and bent to form through-hole pins, or "cut short" and bent to form surface-mount leads. Such lead frames are used for surface mount packages with leads—such as small-outline integrated circuit (SOIC), Quad Flat Package (QFP), etc. -- and for through-hole packages such as dual in-line package (DIP) etc. -- and even for so-called "leadless" or "no-lead" packages—such as quad-flat no-leads package (QFN), etc.

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Wanna Be With You

by: Lead

Nakidashisou na yozora ni
Kasaneawasu kimi kara no YELL
Daijoubu nante NO akirame no ii
Yatsu dake ni wa mou naritakunai
Sono me ni utsuru boku ga kagayaku tame
Wanna be with you
Unmei no nami ni sakarai nagara
And you know it's true
Ikite iku koto ni me wo sorasanai
I live for you (Wanna be with you)
Kizutsuku koto osorete
Iru nara take the lead kikasetai
Yasashisa ijou no kizuna wo
Wanna be with you
Unmei wa mujou daremo ga tamesareru
And you know it's true
Sono tabi ni mayoi utagattari
Wanna be with you
Dakedo kanarazu norikoete miseru kara
And you know it's true
Kimi no soba ni iru yakusoku shiyou
My song for you
Koboreta kanashimi no kakera
Boku ga hiroiatsumeyou
(Lazy Lazy)
Ashi fumishite ita ano koro
(Noisy Noisy)
Dare no koe mo hibikanakatta
(Hazy Hazy)
Kizashi wo ataete kureta
(Shiny Shiny)
Kimi ni misetai hora Change the world
Wanna be with you
Unmei no nami ni sakarai nagara
And you know it's true
Ikite iku koto ni me wo sorasanai
Wanna be with you
Moshimo fuan ga fukai yami he sasotte mo
And you know it's true
Kimi to no sekai nara nanimo kowakunai




Latest News for: lead

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Ragans strikes out 10, leads Royals to a 4-2 victory that stops Guardians' 5-game winning streak

The Oskaloosa Herald 14 Apr 2025
Cole Ragans struck out 10, walked none and allowed four hits in 7 2/3 innings, getting his first win this season as the Kansas City Royals overcame a two-run deficit to beat Cleveland 4-2 and stop the Guardians’ five-game winning ... .
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Esther Gonzalez (2 goals) leads NJ/NY Gotham over Courage

Marietta Daily Journal 14 Apr 2025
Sparked by Esther Gonzalez's two first-half goals, NJ/NY Gotham defeated the visiting North Carolina Courage 3-1 on Sunday to pick up their first win of the season ... .
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McIlroy leads by four as Masters back-nine battle begins

Marietta Daily Journal 14 Apr 2025
Rory McIlroy overcame a nightmare start to seize a four-stroke lead after the first nine holes in Sunday's final round of the Masters as he seeks a victory to complete a career Grand Slam ... .
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Knicks' reserves lead comeback win over Nets

Marietta Daily Journal 14 Apr 2025
Landry Shamet came off the bench to score 29 points, and the short-handed New York Knicks rode a 17-0 third-quarter run to hold off the host Brooklyn Nets 113-105 in the regular-season finale for both teams Sunday ... .
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Jodrey leads Massie to slugfest win over Spartans 17-11

Wilmington News Journal 14 Apr 2025
Kalli Jodrey went 4-for-4 and drove in six runs to lead the Falcons offense ... Izzy Penewit had three hits ... ....
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Lee’s two-homer day leads Giants to series win over Yankees

The News-Gazette 14 Apr 2025
NEW YORK — Compared to the first two games of the San Francisco Giants’ three-game series with the New York Yankees, Sunday afternoon in the Bronx may as well been the Bahamas. The temperature was up, the sun was shining ... .
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Sabonis, Valanciunas lead Kings past Suns in finale

The News-Gazette 14 Apr 2025
SACRAMENTO, Calif. (AP) — Domantas Sabonis and Jonas Valanciunas each had a double-double, and Sacramento clinched homecourt advantage for the Kings first play-in game, beating the Phoenix Suns 109-98 on Sunday ... .
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Kevin Kelsy scores in each half to lead Timbers to 4-2 victory over Sporting KC

The Herald Bulletin 14 Apr 2025
Kevin Kelsy scored in each half as the Portland Timbers upped their unbeaten streak to five with a 4-2 victory over Sporting Kansas City. Portland took the lead for good four minutes into the second half when Antony notched an ... .
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Kodai Senga leads Mets over Athletics 8-0 for fourth straight series win

The Herald Bulletin 14 Apr 2025
Kodai Senga became the first Mets pitcher to threw seven innings this year, and New York beat the Athletics 8-0 for its fourth straight series win. Senga allowed four hits, struck out four and walked two, throwing a season-high 79 ... .
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Nebraska baseball grabs late lead and holds on for win over Iowa

Kearney Hub 14 Apr 2025
Nebraska took advantage of a pair of Iowa errors in the eighth inning to grab the lead for good in a win Sunday afternoon ... .
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Audet’s 2 HR, 5 RBI lead Paul VI softball past Ocean City in autism showcase

NJ 14 Apr 2025
Junior Danielle Audet came to the plate with two on in the first inning of Paul VI’s At-Bats for Autism Acceptance softball game against Ocean City on Sunday ....
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