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Bullet Resistant
Bulletproofing is the process of making an object capable of stopping a bullet or similar high velocity projectiles (e.g. shrapnel). The term bullet resistance is often preferred because few, if any, practical materials provide complete protection against all types of bullets, or multiple hits in the same location, or simply sufficient kinetic (movement) energy to overcome it. Origins In 1887, George E. Goodfellow, of Tombstone, Arizona, documented three cases where bullets had failed to penetrate silk articles of clothing. He described the shooting death of Charlie Storms by gambler Luke Short. Although Storms was shot in the heart, "not a drop of blood" exited the wound. Goodfellow found that, though the bullet did indeed kill Storms, it failed to pass through a silk handkerchief. The handkerchief essentially caught the bullet, but not sufficiently to stop the bullet penetrating Storms. Another example was the killing of Billy Grounds by Assistant City Marshal Billy Breake ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bulletproof Glass Window After A Burglary Attempt
Bulletproofing is the process of making an object capable of stopping a bullet or similar high velocity projectiles (e.g. shrapnel). The term bullet resistance is often preferred because few, if any, practical materials provide complete protection against all types of bullets, or multiple hits in the same location, or simply sufficient kinetic (movement) energy to overcome it. Origins In 1887, George E. Goodfellow, of Tombstone, Arizona, documented three cases where bullets had failed to penetrate silk articles of clothing. He described the shooting death of Charlie Storms by gambler Luke Short. Although Storms was shot in the heart, "not a drop of blood" exited the wound. Goodfellow found that, though the bullet did indeed kill Storms, it failed to pass through a silk handkerchief. The handkerchief essentially caught the bullet, but not sufficiently to stop the bullet penetrating Storms. Another example was the killing of Billy Grounds by Assistant City Marshal Billy Breake ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern California Practitioner
Southern may refer to: Businesses * China Southern Airlines, airline based in Guangzhou, China * Southern Airways, defunct US airline * Southern Air, air cargo transportation company based in Norwalk, Connecticut, US * Southern Airways Express, Memphis-based passenger air transportation company, serving eight cities in the US * Southern Company, US electricity corporation * Southern Music (now Peermusic), US record label * Southern Railway (other), various railways * Southern Records, independent British record label * Southern Studios, recording studio in London, England * Southern Television, defunct UK television company * Southern (Govia Thameslink Railway), brand used for some train services in Southern England Media * ''Southern Daily'' or ''Nanfang Daily'', the official Communist Party newspaper based in Guangdong, China * ''Southern Weekly'', a newspaper in Guangzhou, China * Heart Sussex, a radio station in Sussex, England, previously known as "Southern FM" * 8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Law Enforcement And Corrections Technology Center
The National Law Enforcement and Corrections Technology Center (NLECTC) was originally created in 1994 as a program of the National Institute of Justice's (NIJ's) Office of Science and Technology. Resources The ''States, Major Cities and Counties Regional Center'' offers a resource and outreach mechanism for state, major city and county criminal justice system partners, with a mission of ensuring that larger criminal justice agencies (those having 50 or more sworn personnel) have unbiased access to a full range of relevant scientific and technology-related information. The ''Small, Rural, Tribal and Border Regional Center'' publicizes its programs and services to small, rural, tribal and border agencies across the country. The efforts of these centers complement those of NLECTC-National, which coordinates NIJ's Compliance Testing program and standards development efforts for a variety of equipment used in the public safety arena, and the Centers of Excellence (CoEs), which support ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institute Of Justice
The National Institute of Justice (NIJ) is the research, development and evaluation agency of the United States Department of Justice. NIJ, along with the Bureau of Justice Statistics (BJS), Bureau of Justice Assistance (BJA), Office of Juvenile Justice and Delinquency Prevention (OJJDP), Office for Victims of Crime (OVC), and other program offices, comprise the Office of Justice Programs (OJP) branch of the Department of Justice. History The National Institute of Law Enforcement and Criminal Justice was established on October 21, 1968, under the Omnibus Crime Control and Safe Streets Act of 1968, as a component of the Law Enforcement Assistance Administration (LEAA). In 1978, it was renamed as the National Institute of Justice. Some functions of the LEAA were absorbed by NIJ on December 27, 1979, with passage of the Justice System Improvement Act of 1979. The act, which amended the Omnibus Crime Control and Safe Streets Act of 1968, also led to creation of the Bureau of Justi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Material
A composite material (also called a composition material or shortened to composite, which is the common name) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Typical engineered composite materials include: *Reinforced concrete and masonry *Composite wood such as plywood *Reinforced plastics, such as fibre-reinforced polymer or fiberglass *Ceramic matrix composites ( composite ceramic and metal matrices) *Metal matrix composites *and other advanced composite materials There are various reasons where new material can be favoured. Typical examples include materials which are less expensive, lighter, stronger or more durable when compared with commo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Fiber
Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon composite, or just carbon, are extremely strong and light fiber-reinforced plastics that contain carbon fibers. CFRPs can be expensive to produce, but are commonly used wherever high strength-to-weight ratio and stiffness (rigidity) are required, such as aerospace, superstructures of ships, automotive, civil engineering, sports equipment, and an increasing number of consumer and technical applications. The binding polymer is often a thermoset resin such as epoxy, but other thermoset or thermoplastic polymers, such as polyester, vinyl ester, or nylon, are sometimes used. The properties of the final CFRP product can be affected by the type of additives introduced to the binding matrix (resin). The most common additive is silica, but other addi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lexan
Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent. They are easily worked, molded, and thermoformed. Because of these properties, polycarbonates find many applications. Polycarbonates do not have a unique resin identification code (RIC) and are identified as "Other", 7 on the RIC list. Products made from polycarbonate can contain the precursor monomer bisphenol A (BPA). Structure Carbonate esters have planar OC(OC)2 cores, which confers rigidity. The unique O=C bond is short (1.173 Å in the depicted example), while the C-O bonds are more ether-like (the bond distances of 1.326 Å for the example depicted). Polycarbonates received their name because they are polymers containing carbonate groups (−O−(C=O)−O−). A balance of useful features, including temperature resistance, impact resistance and op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UHMWPE
Ultra-high-molecular-weight polyethylene (UHMWPE, UHMW) is a subset of the thermoplastic polyethylene. Also known as high-modulus polyethylene, (HMPE), it has extremely long chains, with a molecular mass usually between 3.5 and 7.5 million amu. The longer chain serves to transfer load more effectively to the polymer backbone by strengthening intermolecular interactions. This results in a very tough material, with the highest impact strength of any thermoplastic presently made. UHMWPE is odorless, tasteless, and nontoxic. It embodies all the characteristics of high-density polyethylene (HDPE) with the added traits of being resistant to concentrated acids and alkalis, as well as numerous organic solvents. It is highly resistant to corrosive chemicals except oxidizing acids; has extremely low moisture absorption and a very low coefficient of friction; is self-lubricating (see boundary lubrication); and is highly resistant to abrasion, in some forms being 15 times more resistant to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kevlar
Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s as a replacement for steel in racing tires. It is typically spun into ropes or fabric sheets that can be used as such, or as an ingredient in composite material components. Kevlar has many applications, ranging from bicycle tires and racing sails to bulletproof vests, all due to its high tensile strength-to-weight ratio; by this measure it is five times stronger than steel. It is also used to make modern marching drumheads that withstand high impact; and for mooring lines and other underwater applications. A similar fiber called Twaron with the same chemical structure was developed by Akzo in the 1970s; commercial production started in 1986, and Twaron is now manufactured by Teijin. History Poly-paraphenylene terephthalamide (K2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardened Steel
The term hardened steel is often used for a medium or high carbon steel that has been given heat treatment and then quenching followed by tempering. The quenching results in the formation of metastable martensite, the fraction of which is reduced to the desired amount during tempering. This is the most common state for finished articles such as tools and machine parts. In contrast, the same steel composition in annealed state is softer, as required for forming and machining. Depending on the temperature and composition of the steel, it can be hardened or softened. To make steel harder, it must be heated to very high temperatures. The final result of exactly how hard the steel becomes depends on the amount of carbon present in the metal. Only steel that is high in carbon can be hardened and tempered. If a metal does not contain the necessary quantity of carbon, then its crystalline structure cannot be broken, and therefore the physical makeup of the steel cannot be altered. Fre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armor-piercing Shot And Shell
Armour-piercing ammunition (AP) is a type of projectile designed to penetrate either body armour or vehicle armour. From the 1860s to 1950s, a major application of armour-piercing projectiles was to defeat the thick armour carried on many warships and cause damage to their lightly-armoured interiors. From the 1920s onwards, armour-piercing weapons were required for anti-tank warfare. AP rounds smaller than 20 mm are intended for lightly-armoured targets such as body armour, bulletproof glass, and lightly-armoured vehicles. As tank armour improved during World War II, anti-vehicle rounds began to use a smaller but dense penetrating body within a larger shell, firing at very high muzzle velocity. Modern penetrators are long rods of dense material like tungsten or depleted uranium (DU) that further improve the terminal ballistics. History The late 1850s saw the development of the ironclad warship, which carried wrought iron armour of considerable thickness. This armour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
