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.

Metal: A Headbanger's Journey

Metal: A Headbanger's Journey is a 2005 documentary directed by Sam Dunn with Scot McFadyen and Jessica Wise. The film follows 31-year-old Dunn, a Canadian anthropologist, who has been a heavy metal fan since the age of 12. Dunn sets out across the world to uncover the various opinions on heavy metal music, including its origins, culture, controversy, and the reasons it is loved by so many people. The film made its debut at the 2005 Toronto International Film Festival, and was released as a two-disc special edition DVD in the US on September 19, 2006.

A follow-up to the film titled Global Metal premiered at the Bergen International Film Festival on October 17, 2007, and saw limited release in theatres in June 2008. Dunn has also elaborated upon his "Heavy Metal Family Tree" in the VH1 series Metal Evolution, which focuses on one subgenre per episode.

Contents

The film discusses the traits and originators of some of metal's many subgenres, including the New Wave of British Heavy Metal, power metal, nu metal, glam metal, thrash metal, black metal, and death metal. Dunn uses a family-tree-type flowchart to document some of the most popular metal subgenres. The film also explores various aspects of heavy metal culture. Notable segments include Dunn taking a trip to the Wacken Open Air festival, an interview with Dee Snider providing an analysis of the PMRC attack on heavy metal music, and an interview with several Norwegian black metal bands.

Metal (API)

Metal is a low-level, low-overhead hardware-accelerated graphics and compute application programming interface (API) that debuted in iOS 8. It combines functionality similar to OpenGL and OpenCL under one API. It is intended to bring to iOS some of the performance benefits of similar APIs on other platforms, such as Khronos Group's cross-platform Vulkan and Microsoft's Direct3D 12 for Windows. Since June 8, 2015, Metal is available for iOS devices using the Apple A7 or later, as well as Macs (2012 models or later) running OS X El Capitan. Metal also further improves the capabilities of GPGPU programming by introducing compute shaders.

Metal uses a new shading language based on C++11; this is implemented using Clang and LLVM.

Support for Metal on OS X was announced at WWDC 2015.

Performance

Metal should have better performance than OpenGL, for several reasons:

Metal (Wu Xing)

Metal (Chinese: 金; pinyin: jīn), the fourth phase of the Chinese philosophy of Wu Xing, is the decline of the matter, or the matter's decline stage. Metal is yin in character, its motion is inwards and its energy is contracting. It is associated with the autumn, the west, old age, the planet Venus, the color white, dry weather, and the White Tiger (Bai Hu) in Four Symbols. The archetypal metals are silver and gold.

Attributes

In Chinese Taoist thought, Metal attributes are considered to be firmness, rigidity, persistence, strength, and determination. The metal person is controlling, ambitious, forceful, and set in their ways as metal is very strong. They are self-reliant and prefer to handle their problems alone. The metal person is also wise, business-oriented, and good at organization and stability. However, the metal person can also appreciate luxury and enjoy the good things in life. Just as metal can conduct electricity, the metal person has strong impulses and generative powers and can bring about changes and transformations for those who come into contact with them. The metal person is patient, as well as a good person with a strong will.

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 (disambiguation)

Lead has two different pronunciations and several different meanings, usually related to either the chemical element lead (a heavy metal) or the verb to lead.

When pronounced /ˈlɛd/ (rhymes with "bed")

With this pronunciation, "lead" refers to:

The past tense of the verb to lead is led, pronounced /ˈlɛd/. It is often misspelled as lead.

See also:

When pronounced /ˈliːd/ (rhymes with "need")

With this pronunciation, "lead" generally means "first", "ahead", or "guide":

Lead (band)

Lead is a Japanese hip-hop group, under the Record of Pony Canyon/ Flight Master. Their debut was on July 31, 2002 with their single Manatsu no Magic (Mid-Summer Magic).

Biography

Hiroki Nakadoi, Shinya Taniuchi, and Akira Kagimoto all attended Osaka's "Caless Vocal and Dance School" and became good friends. By March 2002, they began doing live street performances, on the streets of Shiroten, Osaka; under the dance unit name of "remix". By May 2002, they renamed the group from "remix" to "flow". After having the name change, the three decided to recruit a fourth member.

Meanwhile, on April 13, 2002 - the "Kyushu/Fukuoka Starlight Audition" was held in Okinawa, Japan on a search for new talent. At the time, thirteen-year-old Keita Furuya and another contestant were declared winners out of the 8,751 hopefuls that had auditioned. Flow tracked down Keita and he soon joined the now four member group "flow" as of May 18, 2002.

On May 23, 2002 - The group underwent another and final name change, officially becoming "Lead", as they hoped to become a leading group of the age.