Air filterA particulate air filter is a device composed of fibrous, or porous materials which removes solid particulates such as dust, pollen, mold, and bacteria from the air. Filters containing an adsorbent or catalyst such as charcoal (carbon) may also remove odors and gaseous pollutants such as volatile organic compounds or ozone. Air filters are used in applications where air quality is important, notably in building ventilation systems and in engines. Some buildings, as well as aircraft and other human-made environments (e.
SyngasSyngas, or synthesis gas, is a mixture of hydrogen and carbon monoxide, in various ratios. The gas often contains some carbon dioxide and methane. It is principally used for producing ammonia or methanol. Syngas is combustible and can be used as a fuel. Historically, it has been used as a replacement for gasoline, when gasoline supply has been limited; for example, wood gas was used to power cars in Europe during WWII (in Germany alone half a million cars were built or rebuilt to run on wood gas).
Volatile organic compoundVolatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. High vapor pressure correlates with a low boiling point, which relates to the number of the sample's molecules in the surrounding air, a trait known as volatility. VOCs are responsible for the odor of scents and perfumes as well as pollutants. VOCs play an important role in communication between animals and plants, e.g. attractants for pollinators, protection from predation, and even inter-plant interactions.
Arctic sea ice ecology and historyThe Arctic sea ice covers less area in the summer than in the winter. The multi-year (i.e. perennial) sea ice covers nearly all of the central deep basins. The Arctic sea ice and its related biota are unique, and the year-round persistence of the ice has allowed the development of ice endemic species, meaning species not found anywhere else. There are differing scientific opinions about how long perennial sea ice has existed in the Arctic. Estimates range from 700,000 to 4 million years. The specialized, sympagic (i.
Greenland ice sheetThe Greenland ice sheet (Grønlands indlandsis, Sermersuaq) is a vast body of ice covering , roughly near 80% of the surface of Greenland. It is sometimes referred to as an ice cap, or under the term inland ice, or its Danish equivalent, indlandsis. The acronym GIS is frequently used in the scientific literature. It is the second largest ice body in the world, after the Antarctic ice sheet. The ice sheet is almost long in a north–south direction, and its greatest width is at a latitude of 77°N, near its northern margin.
Sea iceSea ice arises as seawater freezes. Because ice is less dense than water, it floats on the ocean's surface (as does fresh water ice, which has an even lower density). Sea ice covers about 7% of the Earth's surface and about 12% of the world's oceans. Much of the world's sea ice is enclosed within the polar ice packs in the Earth's polar regions: the Arctic ice pack of the Arctic Ocean and the Antarctic ice pack of the Southern Ocean.
Composition of electronic cigarette aerosolThe chemical composition of the electronic cigarette aerosol varies across and within manufacturers. Limited data exists regarding their chemistry. However, researchers at Johns Hopkins University analyzed the vape clouds of popular brands such as Juul and Vuse, and found "nearly 2,000 chemicals, the vast majority of which are unidentified." The aerosol of e-cigarettes is generated when the e-liquid comes in contact with a coil heated to a temperature of roughly within a chamber, which is thought to cause pyrolysis of the e-liquid and could also lead to decomposition of other liquid ingredients.
Marine prokaryotesMarine prokaryotes are marine bacteria and marine archaea. They are defined by their habitat as prokaryotes that live in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. All cellular life forms can be divided into prokaryotes and eukaryotes. Eukaryotes are organisms whose cells have a nucleus enclosed within membranes, whereas prokaryotes are the organisms that do not have a nucleus enclosed within a membrane.
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.
Gas flareA gas flare, alternatively known as a flare stack, flare boom, ground flare, or flare pit is a gas combustion device used in places such as petroleum refineries, chemical plants and natural gas processing plants, oil or gas extraction sites having oil wells, gas wells, offshore oil and gas rigs and landfills. In industrial plants, flare stacks are primarily used for burning off flammable gas released by safety valves during unplanned over-pressuring of plant equipment.