Candle Visual Wind Audio 蜡烛

维基百科，自由的百科全书

蠟燭，是用蠟或其他燃料所製成，中有燭芯，點火之後可以持續燃燒的用品。
蜡烛一般用于照明，但在电力革命以后逐渐被电灯取代，现在蜡烛多是停电时的备用照明用品。节日或其他特殊日子和宗教場所等也会用到蜡烛。各地的集会或集体悼念活动，常会燃烧蜡烛。中国的传统婚礼会燃烧红烛，以示喜庆；丧礼则会燃烧白烛，以示哀悼。另外蜡烛也用于增温等。 此外蠟燭還象徵犧牲。
原料 [编辑] 蠟燭原來是用動物的油脂，通常為牛脂或蜂蜜蠟所製成。現今通常已改用石油副產品石蠟所製成。 歷史 [编辑] 蠟燭被認為最早出現於公元前30世紀的古埃及，當時古埃及人把蘆葦插在融化的牛脂內製成蠟燭。直到中世紀，南歐及地中海沿岸的蠟燭仍是由牛脂和羊脂製成。中國南唐時期，南唐烈祖李昪下令以出產自江浙一帶的烏桕種子外面蠟層取代動物油脂製成蠟燭，令其製作價格大幅下降，使蠟燭從此在中國得以普及。(這蠟燭應用也反應了烏桕的英文名稱: China tallow tree.)
隨著19世紀歐洲發明提煉石油的方法，蠟燭逐漸改用石蠟製成。
科學演示實驗用途 [编辑] 蠟燭蒸汽於另一端燃燒 高溫二氧化碳使較高之蠟燭先行熄滅
1. 蠟燭蒸汽的燃燒，實驗中以一玻璃管將部分蠟蒸氣導向後點火，於另一端燃燒。
2. 高溫二氧化碳上飄且有滅火作用之演示實驗，實驗中有兩個一高一低兩個蠟燭，以大型玻璃燒杯蓋住，數秒後即可看見較高之蠟燭先行熄滅，而後是較低之蠟燭熄滅。
相關 [编辑] 烛光晚會 紙錢 香 煲蠟

Candle - A candle is a solid block of wax with an embedded wick, which is ignited to provide light, and sometimes heat, and historically was used as a method of keeping time.

A candle manufacturer is traditionally known as a chandler. Various devices have been invented to hold candles, from simple tabletop candle holders, to elaborate chandeliers.

For a candle to burn, a heat source (commonly a naked flame) is used to light the candle's wick, which melts and vaporizes a small amount of fuel, the wax. Once vaporized, the fuel combines with oxygen in the atmosphere to form a flame. This flame provides sufficient heat to keep the candle burning via a self-sustaining chain of events: the heat of the flame melts the top of the mass of solid fuel; the liquefied fuel then moves upward through the wick via capillary action; the liquefied fuel finally vaporizes to burn within the candle's flame.

Candles were once made from tallow and beeswax until after about 1850, they were made mainly from spermaceti and purified animal fats (stearin). Today, most candles are made from paraffin wax. Candles can also be made from beeswax, soy, other plant waxes, and tallow (a by-product of beef-fat rendering). Gel candles are made from a mixture of mineral oil and a polymer.

As the mass of solid fuel is melted and consumed, the candle grows shorter. Portions of the wick that are not emitting vaporized fuel are consumed in the flame. The incineration of the wick limits the exposed length of the wick, thus maintaining a constant burning temperature and rate of fuel consumption. Some wicks require regular trimming with scissors (or a specialized wick trimmer), usually to about one-quarter inch (~0.7 cm), to promote slower, steady burning, and also to prevent smoking. In early times, the wick needed to be trimmed quite frequently, and special candle-scissors, referred to as "snuffers" until the 20th century, were produced for this purpose, often combined with an extinguisher. In modern candles, the wick is constructed so that it curves over as it burns (see picture on the right), so that the end of the wick gets oxygen and is then consumed by fire—a self-trimming wick. Based on measurements of a taper-type, paraffin wax candle, a modern candle typically burns at a steady rate of about 0.1 g/min, releasing heat at roughly 80 W.