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Environmental Pollutants
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Although environmental pollution can be caused by natural events, the word pollution generally implies that the contaminants have an anthropogenic source – that is, a source created by human activities. Pollution is often classed as point source or nonpoint source pollution. In 2015, pollution killed nine million people worldwide (one in six deaths). This remained unchanged in 2019, with little real progress against pollution being identifiable. Air pollution accounted for of these earlier deaths. Major forms of pollution include air pollution, light pollution, litter, noise pollution, plastic pollution, soil contamination, radioactiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litter
Litter consists of waste products that have been discarded incorrectly, without consent, at an unsuitable location. Litter can also be used as a verb; to litter means to drop and leave objects, often man-made, such as aluminum cans, paper cups, food wrappers, cardboard boxes or plastic bottles on the ground, and leave them there indefinitely or for other people to dispose of as opposed to disposing of them correctly. Large and hazardous items of rubbish such as tires, electrical appliances, electronics, batteries and large industrial containers are sometimes dumped in isolated locations, such as national forests and other public lands. It is a human impact on the environment and remains a serious environmental problem in many countries. Litter can exist in the environment for long periods of time before decomposition and be transported over large distances into the world's oceans. Litter can affect the quality of life. Cigarette butts are the most littered item in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Pollution
Visual pollution is the study of secondary impacts of manmade interventions or visible deterioration and negative aesthetic quality of the natural and human-made landscapes around people. It refers to the impacts pollution has in impairing the quality of the landscape and is formed from compounding sources of pollution to create it. Visual pollution disturbs the functionality and enjoyment of a given area, limiting the ability for the wider ecological system, from humans to animals, to prosper and thrive within it from disruption to natural and human-made habitats. Although visual pollution can be caused by natural sources (e.g. wildfires) the predominant cause comes from human sources. As such, visual pollution is not considered a primary source of pollution but a secondary symptom of intersecting pollution sources. Its secondary nature and subjective aspect sometimes makes it difficult to measure and engage with (e.g. within quantitative figures for policymakers). However, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozone
Ozone (), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lower atmosphere to ( dioxygen). Ozone is formed from dioxygen by the action of ultraviolet (UV) light and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the latter, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviolet (UV) radiation. Ozone's odour is reminiscent of chlorine, and detectable by many people at concentrations of as little as in air. Ozone's O3 structure was determined in 1865. The molecule was later proven to have a bent structure and to be weakly diamagnetic. In standard conditions, ozone is a pale blue gas that condenses at cryogenic temperatures to a dark blue liquid and finally a violet-black ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Sector
In macroeconomics, the secondary sector of the economy is an economic sector in the three-sector theory that describes the role of manufacturing. It encompasses industries that produce a finished, usable product or are involved in construction. This sector generally takes the output of the primary sector (i.e. raw materials) and creates finished goods suitable for sale to domestic businesses or consumers and for export (via distribution through the tertiary sector). Many of these industries consume large quantities of energy, require factories and use machinery; they are often classified as light or heavy based on such quantities. This also produces waste materials and waste heat that may cause environmental problems or pollution (see negative externalities). Examples include textile production, car manufacturing, and handicraft. Manufacturing is an important activity in promoting economic growth and development. Nations that export manufactured products tend to gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Oxide
Nitrogen oxide may refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds: Charge-neutral * Nitric oxide (NO), nitrogen(II) oxide, or nitrogen monoxide *Nitrogen dioxide (), nitrogen(IV) oxide * Nitrogen trioxide (), or nitrate radical * Nitrous oxide (), nitrogen(0,II) oxide * Dinitrogen dioxide (), nitrogen(II) oxide dimer * Dinitrogen trioxide (), nitrogen(II,IV) oxide *Dinitrogen tetroxide (), nitrogen(IV) oxide dimer * Dinitrogen pentoxide (), nitrogen(V) oxide, or nitronium nitrate * Nitrosyl azide (), nitrogen(−I,0,I,II) oxide *Nitryl azide () * Oxatetrazole () * Trinitramide ( or ), nitrogen(0,IV) oxide Anions * Nitroxide () * Nitrite ( or ) * Nitrate () * Peroxynitrite ( or ) * Peroxynitrate ( or ) * Orthonitrate (, analogous to phosphate ) * Hyponitrite ( or ) * Trioxodinitrate or hyponitrate ( or ) * Nitroxylate ( or ) * Dinitramide ( or ) Cations * Nitrosonium ( or ) *Nitronium ( or ) Atmospheric sciences In atmospheric chemistry: * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorofluorocarbon
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propane. They are also commonly known by the DuPont brand name Freon. The most common representative is dichlorodifluoromethane (R-12 or Freon-12). Many CFCs have been widely used as refrigerants, propellants (in aerosol applications), and solvents. Because CFCs contribute to ozone depletion in the upper atmosphere, the manufacture of such compounds has been phased out under the Montreal Protocol, and they are being replaced with other products such as hydrofluorocarbons (HFCs) including R-410A and R-134a. Structure, properties and production As in simpler alkanes, carbon in the CFCs bond with tetrahedral symmetry. Because the fluorine and chlorine atoms differ greatly in size and effective charge from hydrogen and from each othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Dioxide
Sulfur dioxide ( IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a toxic gas responsible for the odor of burnt matches. It is released naturally by volcanic activity and is produced as a by-product of copper extraction and the burning of sulfur- bearing fossil fuels. Structure and bonding SO2 is a bent molecule with ''C''2v symmetry point group. A valence bond theory approach considering just ''s'' and ''p'' orbitals would describe the bonding in terms of resonance between two resonance structures. The sulfur–oxygen bond has a bond order of 1.5. There is support for this simple approach that does not invoke ''d'' orbital participation. In terms of electron-counting formalism, the sulfur atom has an oxidation state of +4 and a formal charge of +1. Occurrence Sulfur dioxide is found on Earth and exists in very small concentrations and in the atmosphere at about 1 ppm. On other p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Monoxide
Carbon monoxide ( chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simplest molecule of the oxocarbon family. In coordination complexes the carbon monoxide ligand is called carbonyl. It is a key ingredient in many processes in industrial chemistry. The most common source of carbon monoxide is the partial combustion of carbon-containing compounds, when insufficient oxygen or heat is present to produce carbon dioxide. There are also numerous environmental and biological sources that generate and emit a significant amount of carbon monoxide. It is important in the production of many compounds, including drugs, fragrances, and fuels. Upon emission into the atmosphere, carbon monoxide affects several processes that contribute to climate change. Carbon monoxide has important biological roles across phylog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Particulates
Particulates – also known as atmospheric aerosol particles, atmospheric particulate matter, particulate matter (PM) or suspended particulate matter (SPM) – are microscopic particles of solid or liquid matter suspended in the air. The term '' aerosol'' commonly refers to the particulate/air mixture, as opposed to the particulate matter alone. Sources of particulate matter can be natural or anthropogenic. They have impacts on climate and precipitation that adversely affect human health, in ways additional to direct inhalation. Types of atmospheric particles include suspended particulate matter; thoracic and respirable particles; inhalable coarse particles, designated PM, which are coarse particles with a diameter of 10 micrometers (μm) or less; fine particles, designated PM, with a diameter of 2.5 μm or less; ultrafine particles, with a diameter of 100 nm or less; and soot. The IARC and WHO designate airborne particulates as a Group 1 carcinogen. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contaminants
Contamination is the presence of a constituent, impurity, or some other undesirable element that spoils, corrupts, infects, makes unfit, or makes inferior a material, physical body, natural environment, workplace, etc. Types of contamination Within the sciences, the word "contamination" can take on a variety of subtle differences in meaning, whether the contaminant is a solid or a liquid, as well as the variance of environment the contaminant is found to be in. A contaminant may even be more abstract, as in the case of an unwanted energy source that may interfere with a process. The following represent examples of different types of contamination based on these and other variances. Chemical contamination In chemistry, the term "contamination" usually describes a single constituent, but in specialized fields the term can also mean chemical mixtures, even up to the level of cellular materials. All chemicals contain some level of impurity. Contamination may be recognized or not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smog In The Centre Of Moscow, 06
Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a portmanteau of the words ''smoke'' and '' fog'' to refer to smoky fog due to its opacity, and odor. The word was then intended to refer to what was sometimes known as pea soup fog, a familiar and serious problem in London from the 19th century to the mid-20th century. This kind of visible air pollution is composed of nitrogen oxides, sulfur oxide, ozone, smoke and other particulates. Man-made smog is derived from coal combustion emissions, vehicular emissions, industrial emissions, forest and agricultural fires and photochemical reactions of these emissions. Smog is often categorized as being either summer smog or winter smog. Summer smog is primarily associated with the photochemical formation of ozone. During the summer season when the temperatures are warmer and there is more sunlight present, photochemical smog is the dominant type of smog formation. Dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United Nations
The United Nations (UN) is an intergovernmental organization whose stated purposes are to maintain international peace and security, develop friendly relations among nations, achieve international cooperation, and be a centre for harmonizing the actions of nations. It is the world's largest and most familiar international organization. The UN is headquartered on international territory in New York City, and has other main offices in Geneva, Nairobi, Vienna, and The Hague (home to the International Court of Justice). The UN was established after World War II with the aim of preventing future world wars, succeeding the League of Nations, which was characterized as ineffective. On 25 April 1945, 50 governments met in San Francisco for a conference and started drafting the UN Charter, which was adopted on 25 June 1945 and took effect on 24 October 1945, when the UN began operations. Pursuant to the Charter, the organization's objectives include maintaining internationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
