HeterojunctionA heterojunction is an interface between two layers or regions of dissimilar semiconductors. These semiconducting materials have unequal band gaps as opposed to a homojunction. It is often advantageous to engineer the electronic energy bands in many solid-state device applications, including semiconductor lasers, solar cells and transistors. The combination of multiple heterojunctions together in a device is called a heterostructure, although the two terms are commonly used interchangeably.
High-temperature superconductivityHigh-temperature superconductors (abbreviated high-Tc or HTS) are defined as materials with critical temperature (the temperature below which the material behaves as a superconductor) above , the boiling point of liquid nitrogen. They are only "high-temperature" relative to previously known superconductors, which function at even colder temperatures, close to absolute zero. The "high temperatures" are still far below ambient (room temperature), and therefore require cooling.
Health effects of electronic cigarettesThe use of electronic cigarettes (vaping) carries health risks. The risk depends on the fluid and varies according to design and user behavior. In the United Kingdom, vaping is considered by some to be around 95% less harmful than tobacco after a controversial landmark review by Public Health England. E-cigarettes reduce lung function, reduce cardiac muscle function, and increase inflammation. Traditional cigarettes have a higher damage record than vaping.
Electronic cigaretteAn electronic cigarette (commonly and nowadays known as a vape) is a device that simulates tobacco smoking. It consists of an atomizer (often a cotton wick and a heating element coil), a power source such as a battery, and a container such as a cartridge or tank filled with liquid. Instead of smoke, the user inhales "vapor" (though technically primarily an aerosol). As such, using an e-cigarette is often called "vaping". The atomizer is a heating element that vaporizes a liquid solution called e-liquid, which quickly cools into an aerosol of tiny droplets, vapor and air.
