Science homework

The active material in a helium neon laser:

The active laser medium (also called gain medium or lasing medium) is the source of optical gain within a laser. The gain results from the stimulated emission of electronic or molecular transitions to a lower energy state from a higher energy state previously populated by a pump source.

Bronze:Active metal brazing is a form of brazing which allows metal to be joined to ceramic without metallization. curamik® Active Metal Brazed (AMB) substrates consist of a ceramic isolator -- Si3N4 (silicon nitride) -- onto which pure copper is brazed in a high temperature vacuum brazing process.

AMB is the substrate of choice for applications like automotive, wind mill turbines, traction, and high voltage DC transmission where high reliability, heat dissipation, and partial discharge are required. The high heat conductivity of Si3N4 (90 W/mK), as well as the high heat capacity and heat spreading provided by the thick copper layer (up to 80µmmake curamik® Ceramic Substrates irreplaceable in high power electronics.

Cloudy ice cubes:The main reason is that the (hopefully) crystal-clear water you pour into the ice trays is not as pure as it seems, containing small amounts of (hopefully) harmless suspended minerals and sediment.

Because all objects freeze from the outside in, the center of the cube is the last to solidify. Water free of minerals and impurities freezes first, pushing the cloudy parts containing the sediment (and tiny trapped air bubbles) toward the center. The result is a harmless (but not particularly photogenic) ice cube clouding.

Not only do ice cubes cloud in the freezer, but they also shrink noticeably after about a week or two due to sublimation, the term used for evaporation directly from the solid to gas phase.

Ginger ale:Ginger ale is a carbonated soft drink flavoured with ginger in one of two ways. The golden style is credited to the American doctor Thomas Cantrell. The dry style (also called the pale style) is a paler drink with a much milder ginger flavour, and was created by Canadian John McLaughlin.Ginger ale commonly contains carbonated water, sugar or HFCS, and artificial or natural ginger-flavour. Ginger content is often listed on labels in a general "natural aroma" or "Natural flavoring" statement, to preserve secrecy of the complex proprietary mix of spices, fruits and other flavours used. Lemon, lime, and cane sugar are the most common of ingredients. Pineapple and honey are also occasional ingredients.^[3] Ginger ale can also contain yeast, when carbonated with natural fermentation.

Most commercial ginger ales made in the United States are made with high fructose corn syrup as a sweetener.

Observation:The materials used to activate each thing are really different first in the state and second in the amount of protons,neutrons and electron they have.

The active materials of the previous things are not the same some are sweet,some are metals ,etc