SUMMARY / RELATED TOPICS

Fuze

In military munitions, a fuze is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder; the relative complexity of the earliest fuze designs can be seen in cutaway diagrams. A fuze is a device. In addition, a fuze will have safety and arming mechanisms that protect users from premature or accidental detonation. For example, an artillery fuze's battery is activated by the high acceleration of cannon launch, the fuze must be spinning before it will function. "Complete bore safety" can be achieved with mechanical shutters that isolate the detonator from the main charge until the shell is fired. A fuze may contain only the electronic or mechanical elements necessary to signal or actuate the detonator, but some fuzes contain a small amount of primary explosive to initiate the detonation. Fuzes for large explosive charges may include an explosive booster. Professional publications about explosives and munitions distinguish the "fuse" and "fuze" spelling.

The UK Ministry of Defence states: FUSE: Cord or tube for the transmission of flame or explosion consisting of cord or rope with gunpowder or high explosive spun into it. FUZE: A device with explosive components designed to initiate a main charge. Oliver Hogg states the following about fuze: The word "fuze" is spelt "fuse" by those unacquainted with artillery usage; this is incorrect. "Fuse", derived from fusus, the past participle of fundo, means "to melt", e.g. the term "fuse-wire" used in electrical circuits. "Fuze", on the other hand, is the shortened or modern method of spelling "fuzee", meaning a tube filled with combustible material. It is a derivation of a spindle and from the French fusee, a spindle full of thread, it is well to make this point at the outset. It was spelled with either's' or'z', both spellings can still be found. In the United States and some military forces, fuze is used to denote a sophisticated ignition device incorporating mechanical and/or electronic components as opposed to a simple burning fuse.

The situation of usage and the characteristics of the munition it is intended to activate affect the fuze design e.g. its safety and actuation mechanisms. Artillery fuzes are tailored to function in the special circumstances of artillery projectiles; the relevant factors are the projectile's initial rapid acceleration, high velocity and rapid rotation, which affect both safety and arming requirements and options, the target may be moving or stationary. Artillery fuzes may be initiated by a timer mechanism, impact or detection of proximity to the target, or a combination of these. Requirements for a hand grenade fuze are defined by the projectile's small size and slow delivery over a short distance; this necessitates manual arming before throwing as the grenade has insufficient initial acceleration for arming to be driven by "setback" and no rotation to drive arming by centrifugal force. Aerial bombs can be detonated either by a fuze, which contains a small explosive charge to initiate the main charge, or by a "pistol", a firing pin in a case which strikes the detonator when triggered.

The pistol may be considered a part of the mechanical fuze assembly. The main design consideration is that the bomb that the fuze is intended to actuate is stationary, the target itself is moving in making contact. Relevant design factors in naval mine fuzes are that the mine may be static or moving downward through the water, the target is moving on or below the water surface above the mine. Time fuzes detonate after a set period of time by using one or more combinations of mechanical, pyrotechnic or chemical timers. Depending on the technology used, the device may self-destruct some seconds, hours, days, or months after being deployed. Early artillery time fuzes were nothing more than a hole filled with gunpowder leading from the surface to the centre of the projectile; the flame from the burning of the gunpowder propellant ignited this "fuze" on firing, burned through to the centre during flight igniting or exploding whatever the projectile may have been filled with. By the 19th century devices more recognisable as modern artillery "fuzes" were being made of selected wood and trimmed to burn for a predictable time after firing.

These were still fired from smoothbore muzzle-loaders with a large gap between the shell and barrel, still relied on flame from the gunpowder propellant charge escaping past the shell on firing to ignite the wood fuze and hence initiate the timer. In the mid-to-late 19th century adjustable metal time fuzes, the fore-runners of today's time fuzes, containing burning gunpowder as the delay mechanism became common, in conjunction with the introduction of rifled artillery. Rifled guns introduced a tight fit between shell and barrel and hence could no longer rely on the flame from the propellant to initiate the timer; the new metal fuzes use the shock of firing and/or the projectiles's rotation to "arm" the fuze and initiate the timer: hence introducing a safety factor absent. During World War I, mechanical, or clockwork, time fuzes were introduced for artillery by Germany, some variants are still in use; as late

Anteater

Anteater is a common name for the four extant mammal species of the suborder Vermilingua known for eating ants and termites. The individual species have other names in other languages. Together with the sloths, they are within the order Pilosa; the name "anteater" is colloquially applied to the unrelated aardvark, echidnas and some members of the Oecobiidae. Extant species are the giant anteater Myrmecophaga tridactyla, about 1.8 m long including the tail. The anteaters are more related to the sloths than they are to any other group of mammals, their next closest relations are armadillos. There are four extant species in three genera: Giant anteater Silky anteater Northern and southern tamandua There are several extinct genera as well. Order Pilosa Suborder Folivora Suborder Vermilingua Family Cyclopedidae Genus Cyclopes Silky anteater Genus †Palaeomyrmidon Family Myrmecophagidae Genus Myrmecophaga Giant anteater Genus †Neotamandua Genus Tamandua Northern tamandua Southern tamandua Genus †Protamandua Anteaters are one of three surviving families of a once diverse group of mammals that occupied South America while it was geographically isolated from an invasion of animals from North America, the other two being the sloths and the armadillos.

At one time, anteaters were assumed to be related to aardvarks and pangolins because of their physical similarities to those animals, but these similarities have since been determined to be not a sign of a common ancestor, but of convergent evolution. All have evolved powerful digging forearms, long tongues, toothless, tube-like snouts to subsist by raiding termite mounds; this similarity is the reason aardvarks are commonly called "anteaters". All anteaters have elongated snouts equipped with a thin tongue that can be extended to a length greater than the length of the head, they use their large, curved foreclaws to tear open ant and termite mounds and for defense, while their dense and long fur protects them from attacks from the insects. All species except the giant anteater have a long prehensile tail. Anteaters are solitary mammals prepared to defend their 1.0- to 1.5-mi2 territories. They do not enter a territory of another anteater of the same sex, but males enter the territory of associated females.

When a territorial dispute occurs, they vocalize and can sometimes sit on or ride the back of their opponents. Anteaters have poor sight but an excellent sense of smell, most species depend on the latter for foraging and defence, their hearing is thought to be good. With a body temperature fluctuating between 33 and 36 °C, like other xenarthrans, have among the lowest body temperatures of any mammal, can tolerate greater fluctuations in body temperature than most mammals, its daily energy intake from food is only greater than its energy need for daily activities, anteaters coordinate their body temperatures so they keep cool during periods of rest, heat up during foraging. Adult males are larger and more muscular than females, have wider heads and necks. Visual sex determination can, however, be difficult, since the penis and testes are located internally between the rectum and urinary bladder in males and females have a single pair of mammae near the armpits. Fertilization occurs by contact transfer without intromission, similar to some lizards.

Polygynous mating results in a single offspring. The large foreclaws prevent mothers from grasping their newborns and they therefore have to carry the offspring until they are self-sufficient. Anteaters are specialized to feed on small insects, with each anteater species having its own insect preferences: small species are specialized on arboreal insects living on small branches, while large species can penetrate the hard covering of the nests of terrestrial insects. To avoid the jaws and other defences of the invertebrates, anteaters have adopted the feeding strategy of licking up large numbers of ants and termites as as possible — an anteater spends about a minute at a nest before moving on to another — and a giant anteater has to visit up to 200 nests per day to consume the thousands of insects it needs to satisfy its caloric requirements; the anteater's tongue is covered with thousands of tiny hooks called filiform papillae which are used to hold the insects together with large amounts of saliva.

Swallowing and the movement of the tongue are aided by side-to-side movements of the jaws. The tongue is attached to the sternum and moves quickly, flicking 150 times per minute; the anteater's stomach, similar to a bird's gizzard, has hardened folds and uses strong contractions to grind the insects. Silky anteaters and northern tamanduas extend their ranges as far north as southeastern Mexico, while giant anteaters can be found as far north as Central America. Southern tamanduas range south to Uruguay and the ranges of all species except the

Desert rose (crystal)

Desert rose is the colloquial name given to rose-like formations of crystal clusters of gypsum or baryte which include abundant sand grains. The'petals' are crystals flattened on the c crystallographic axis, fanning open in radiating flattened crystal clusters; the rosette crystal habit tends to occur when the crystals form in arid sandy conditions, such as the evaporation of a shallow salt basin. The crystals form a circular array of flat plates, giving the rock a shape similar to a rose blossom. Gypsum roses have better defined, sharper edges than baryte roses. Celestine and other bladed evaporite minerals may form rosette clusters, they can appear either as a single rose-like bloom or as clusters of blooms, with most sizes ranging from pea sized to 4 inches in diameter. The ambient sand, incorporated into the crystal structure, or otherwise encrusts the crystals, varies with the local environment. If iron oxides are present, the rosettes take on a rusty tone; the desert rose may be known by the names: sand rose, rose rock, selenite rose, gypsum rose and baryte rose.

Rose rocks are found in Tunisia, Morocco, Jordan, Saudi Arabia, Egypt, the United Arab Emirates, Mongolia, the United States, Australia, South Africa and Namibia. Rose rock in Oklahoma was formed during the Permian Period, 250 million years ago, when western and central Oklahoma was covered by a shallow sea; as the sea retreated, baryte precipitated out of the water and crystallized around grains of quartz sand. This left behind large formation of reddish sandstone, locally called Garber Sandstone, containing deposits of rose rock; the rose rock was selected as the official rock of the US state of Oklahoma in 1968. The average size of rose; the largest recorded by the Oklahoma Geological Survey was 17 inches across and 10 inches high, weighing 125 pounds. Clusters of rose rocks up to 39 inches tall and weighing more than 1,000 pounds have been found. Timberlake Rose Rock Museum in Noble, Oklahoma 3D model of a desert rose