Реферат по предмету "Иностранный язык"


Pyrotechnics Essay Research Paper PYROTECHNICSPyrotechnics special effects

Pyrotechnics Essay, Research Paper

PYROTECHNICS

Pyrotechnics special effects are widely used in motion picture production to create all types of effects involving explosions, fires, light, smoke and sound concussions. The types of pyrotechnics materials used include flash powder, flash paper, gun cotton, black powder (gunpowder), smokeless powder, detonator explosives, and many more. They are used in bullet hits (squibs), blank cartridges, flash pots, fuses, mortars, smoke pots, sparkle pots, etc.

The main problems of pyrotechnics include prematurely triggering the pyrotechnic effect, use of larger quantities or more dangerous materials than needed, causing a fire, lack of adequate fire extinguishing capabilities, and, of course, inadequately trained and experienced pyrotechnics operators. As a result of these risks, all pyrotechnics special effects are regulated at the federal, state and local level.

In general, all pyrotechnics are explosives, but not all explosives are pyrotechnics. Class A explosives (high explosives) are materials like dynamite and Primacord which may detonate even if unconfined. Pyrotechnic special effects materials are Class B explosives. They will burn, but not explode unless confined. Examples are black powder and pellet powder, safety fuses, igniters, igniter cord, fuse lighters, Class B special fireworks, and Class B composite solids propellants. Class C explosives are common fireworks. Note that short lengths of Primacord may be classified as Class C under certain conditions. Both Class B and C explosives are also called low explosives.

All pyrotechnic materials and other explosives consist of an oxidizer (source of oxygen) and a reducer (fuel). Examples of oxidizers include potassium nitrate, strontium nitrate, potassium perchlorate and potassium chlorate. Examples of fuels include metals like magnesium and aluminum, sulfur, silicon dioxide, and organic fuels like charcoal, starch, resins, and chlorinated hydrocarbons. The choice of fuel and oxidizer determines the type of effect (flash, smoke, sound, etc.) its color, and its intensity.

There are two basic types of pyrotechnic materials: single component and two component systems. Single component materials will either burn if ignited, or explode if ignited when enclosed, since the oxidizer and fuel are in the same mixture. Flash paper, for example, is a partially nitrated cellulose and contains both fuel and oxidizer internally. The traditional black powder has potassium nitrate as the oxidizer, and sulfur and charcoal as fuels.

In two component or binary systems, the oxidizer and fuel are separate components which are transported and stored separately and only mixed when ready to use. These separate components should be prepackaged and labeled as A and B. A typical binary system could have strontium nitrate as the oxidizer component and magnesium and aluminum as the fuel. It is important to store oxidizers carefully since they can utilize many types of organic materials as fuels. Potassium chlorate, for example, is one of the best oxidizers, but is particularly dangerous because it is so reactive.

Lycopodium is also used by pyrotechnicians for fire effects. It is not actually a pyrotechnics materials but a combustible material. Since it is a combustible, organic dust, it is explosive when enclosed.




Не сдавайте скачаную работу преподавателю!
Данный реферат Вы можете использовать для подготовки курсовых проектов.

Поделись с друзьями, за репост + 100 мильонов к студенческой карме :

Пишем реферат самостоятельно:
! Как писать рефераты
Практические рекомендации по написанию студенческих рефератов.
! План реферата Краткий список разделов, отражающий структура и порядок работы над будующим рефератом.
! Введение реферата Вводная часть работы, в которой отражается цель и обозначается список задач.
! Заключение реферата В заключении подводятся итоги, описывается была ли достигнута поставленная цель, каковы результаты.
! Оформление рефератов Методические рекомендации по грамотному оформлению работы по ГОСТ.

Читайте также:
Виды рефератов Какими бывают рефераты по своему назначению и структуре.

Сейчас смотрят :

Реферат Традиции и пассионарность в изучении истории народов России
Реферат Сущность понятия "социокультурный эталон здоровья"
Реферат «Чинники, що формують сприятливий інвестиційний клімат в Україні»
Реферат Аналитическое дешифрование космических снимков
Реферат Антикризисное управление 2
Реферат Геологическое обоснование постановки поисковых работ на нефть и газ
Реферат Денежная масса и скорость обращения денег 2
Реферат Climax Essay Research Paper The Climax
Реферат Реклама в системе маркетинговых коммуникаций
Реферат Экспериментальное исследование психических моделей гапер- и гиповесомости
Реферат Transcendetalism The New Religion Essay Research Paper
Реферат Жизнь и творчество Алексея Кольцова
Реферат Аудит безналичных расчетовна примере ООО ПТФ Родник
Реферат Mafia Essay Research Paper Throughout history crime
Реферат О понятии интеллектуального потенциала и способах его измерения