title: Murrieta, California

text: In the Riverside County Board of Supervisors, Murrieta is in the Third District, represented by Chuck Washington.


title: Murrieta, California

text: The city of Murrieta is served by the Murrieta Valley Unified School District (MVUSD). The district contains eleven elementary (K-5) schools, four middle (6-8) schools, three comprehensive high (9-12) schools (Murrieta Valley High School, Vista Murrieta High School, Murrieta Mesa High School), one continuation school (Creekside High School), and one independent study school.


title: Murrieta, California

text: Calvary Chapel Bible College operated at the Murrieta Hot Springs Resort site from 1994 until 2022. Its affiliated private comprehensive (K-9) school at Calvary Chapel Murrieta also serves the Murrieta community. There had been a senior high school in the Calvary Chapel Murrieta system, but it closed in 2019. Mt. San Jacinto College is the nearest community college (with locations in Temecula and Menifee) and the University of California, Riverside (UCR) is the nearest public university. The city is also home to a University of Phoenix learning center and an Azusa Pacific University satellite campus.


title: Murrieta, California

text: The area of southwest Riverside County is served by television station Channel 27, broadcast from a hilltop in Murrieta.


title: Murrieta, California

text: Murrieta is served by two major Interstate highways: I-15 runs through the western portion of the city while I-215 runs through the eastern portion. Historic U.S. Route 395 (Jefferson Avenue/Ivy Street/Washington Avenue) passes through the city's downtown and State Route 79 (Winchester Road) defines much of the city's eastern border.


title: Murrieta, California

text: The city may become host to the high-speed rail (HSR) that voters approved in 2008 with Prop 1A. The proposed HSR station is projected to handle 8,000 daily riders. The program-level HSR route alignment has placed this station between Murrieta and Temecula near the I-15 and I-215 freeway interchange.


title: Murrieta, California

text: The Murrieta Fire Department was an all-volunteer fire department for 38 years. In 1987, it became a municipal fire protection district. It has been the city's primary paramedic service provider since 2000, and changed its name in 2017 to Murrieta Fire and Rescue. As of 2022, the department has five stations throughout the city, and operates a primary fleet of four type-1 engines, one quint-style truck, and two type-6 engines.


title: Murrieta, California

text: The Murrieta Police Department was founded in 1992. As of 2022, the department had about 100 sworn officers and approximately 50 support staff.


title: Murrieta, California

text: Murrieta is served by two hospitals: Loma Linda University Medical Center and Rancho Springs Medical Center.


title: Yakuza Kiwami 2

text: Yakuza Kiwami 2 is an action-adventure video game developed by Ryu Ga Gotoku Studio and published by Sega. It is a remake of the 2006 video game "Yakuza 2" for the PlayStation 2, and is the "Yakuza" series' second remake title following 2016's "Yakuza Kiwami". It was developed using the Dragon game engine from "Yakuza 6". The game was released for PlayStation 4 on December 7, 2017 in Japan, and worldwide on August 28, 2018. It was released for Windows worldwide on Steam on May 9, 2019 and released for Xbox One on July 30, 2020.


title: Yakuza Kiwami 2

text: "Yakuza Kiwami 2" was followed up by the spinoff titles "" and "Judgment" in 2018, and the next mainline installment "" in 2020.


title: Yakuza Kiwami 2

text: "Yakuza Kiwami 2" is a remake of "Yakuza 2", and is an action-adventure game set in an open world environment and played from a third-person perspective. Similar to the previous remake title, "Yakuza Kiwami", "Kiwami 2" follows the same plot structure of "Yakuza 2" while adding new gameplay features and enhancements from later titles, as well as new story elements to resolve confusing plot points in the original release and tie the game more closely to other titles in the series. The player controls series protagonist Kazuma Kiryu as they explore the fictional Japanese districts of Kamurocho, Tokyo and Sotenbori, Osaka, based on the real life locations of Kabukicho and Dōtonbori, respectively. Combat is based on that previously seen in "Yakuza 6", though with a variety of new moves and special cinematic 'Heat Moves'. A new story scenario, entitled "The Majima Saga" features recurring series anti-hero Goro Majima as a playable character. The Cabaret Club minigame from "Yakuza 0" returns, as does the Clan Creator from "Yakuza 6", bringing in New Japan Pro-Wrestling stars Keiji Mutoh, Masahiro Chono, Riki Choshu, Genichiro Tenryu, and Tatsumi Fujinami.


title: Yakuza Kiwami 2

text: A year after leaving his former life in the Tojo Clan behind, ex-yakuza Kazuma Kiryu is called back into action when the clan's Fifth Chairman, Yukio Terada, is murdered by assassins from a rival organization, the Omi Alliance. Returning to Kamurocho, Kiryu must find a new chairman for the Tojo Clan and prevent an all-out war between the Tojo and the Omi, bringing him into conflict with Ryuji Goda, the legendary "Dragon Of Kansai" of the Omi Alliance.


title: Yakuza Kiwami 2

text: A new scenario, entitled "The Majima Saga" exclusive to "Kiwami 2" explains how Majima came to leave the Tojo Clan following the death of his patron, Futoshi Shimano, a year earlier and form a legitimate enterprise, "Majima Construction", between "Yakuza" and "Yakuza 2". The scenario also features the return of Makoto Makimura, a major character of Majima's story in "Yakuza 0".


title: Yakuza Kiwami 2

text: In February 2006, Tojo Clan's Fifth Chairman Yukio Terada announces a reformation plan for the clan, which requires a replacement for the clan captain position. Up in the run for the position were newcomer Akinobu Uematsu, Kei Ibuchi and Goro Majima, who were making the most profits among the clan. Having no interest in the position and only participating to ensure the other families can band together to keep the newcomers from seizing power, Majima returns to Kamurocho, where he finds himself ambushed by several assassins. After quickly dealing with them, Majima returns to his family office, where he finds his men beaten supposedly by the Uematsu Family. Majima heads to Uematsu's office, but finds Uematsu himself shot dead. After reporting the incident to Tojo Clan members, Majima is tipped by Kazama Family patriarch Osamu Kashiwagi to find the Florist of Sai, who can provide him information. Upon meeting with the Florist, he agrees to help Majima in exchange for the latter's agreement in running the Florist's old base in Purgatory. Majima learns that one of his subordinates, Ryota Kawamura, was last seen at the crime scene. He travels back to Sotenbori to track down Kawamura, and eventually learns that he's a regular gambler who frequents the massage parlor Hogushi Kaiken. While at the parlor, Majima receives service from a woman named Tateyama, who turns out to be Makoto Makimura, who Majima saved from the Tojo Clan 18 years prior. Majima, while attempting to hide his identity, learns that Makoto still kept her old watch as a memento of her savior.


title: Yakuza Kiwami 2

text: Majima later picks up a tip that Kawamura murdered an Omi Alliance officer at the Cabaret Grand. He heads there and confronts Kawamura. The latter is easily defeated, but is then shot dead by Ibuchi, who exploited Kawamura's debt to use him to get rid of Uematsu, in order to spark a war between the Omi Alliance and the Tojo Clan, which would lead to their eventual merging and Ibuchi seizing power from Terada. Majima defeats Ibuchi, but the latter commits suicide rather than allowing himself to be arrested to incite conflict between both sides. In the aftermath, Majima and Terada come to an agreement to disband his family, as a gesture of apology for Kawamura's action against the Omi Alliance. Majima and the remnants of his family then form Majima Construction, and begin work on the Kamurocho Hills complex. Some time later, Makoto leaves the country with her family; she receives an anonymous gift prior to her departure, which turns out to be a replacement strap for her watch. Realizing that her customer was her savior from 18 years as only those who lived back then would have known the original design, Makoto finally finds comfort knowing she has no regrets leaving Japan.


title: Yakuza Kiwami 2

text: "Yakuza Kiwami 2" was initially leaked on August 24, 2017 via a listing on the Taiwanese PlayStation Store. The title was officially announced two days later alongside "", "Yakuza Online", and "". The game runs on the Dragon Engine which was previously used in "Yakuza 6". Several characters were recast for the remake, including Hakuryu as Ryo Takashima, Houka Kinoshita as Wataru Kurahashi, and Yuichi Kimura as Tsutomo Bessho. The in-game arcade features playable versions of "Virtua Fighter 2" and "".


title: Yakuza Kiwami 2

text: Japanese rock band SiM provided theme song in Kiwami 2. The first song "A" serves as opening theme while the second song "Sound of the Breath" serves as an insert song. Both of these themes are also featured in the ending credits of the game.


title: Yakuza Kiwami 2

text: "Yakuza Kiwami 2" was well received by critics. It was the best selling game in Japan during its debut week, selling 131,931 units; this was the lowest debut for a "Yakuza" game, which was noted as expected due to being the first stand-alone PlayStation 4 title that is not a new main entry. The PC version was among the best-selling new releases of the month on Steam.


title: Yakuza Kiwami 2

text: "Famitsu" liked the seamless transitions when entering shops or starting battles, and enjoyed being able to use various items in the city as weapons.


title: Yakuza Kiwami 2

text: The game was nominated for the Freedom Tower Award for Best Remake at the New York Game Awards, and for "Animation, Technical" and "Game, Classic Revival" at the National Academy of Video Game Trade Reviewers Awards.


title: Thermodynamic free energy

text: The thermodynamic free energy is a concept useful in the thermodynamics of chemical or thermal processes in engineering and science. The change in the free energy is the maximum amount of work that a thermodynamic system can perform in a process at constant temperature, and its sign indicates whether the process is thermodynamically favorable or forbidden. Since free energy usually contains potential energy, it is not absolute but depends on the choice of a zero point. Therefore, only relative free energy values, or changes in free energy, are physically meaningful.


title: Thermodynamic free energy

text: The free energy is the portion of any first-law energy that is available to perform thermodynamic work at constant temperature, "i.e.", work mediated by thermal energy. Free energy is subject to irreversible loss in the course of such work. Since first-law energy is always conserved, it is evident that free energy is an expendable, second-law kind of energy. Several free energy functions may be formulated based on system criteria. Free energy functions are Legendre transforms of the internal energy.


title: Thermodynamic free energy

text: The Gibbs free energy is given by , where "H" is the enthalpy, "T" is the absolute temperature, and "S" is the entropy. , where "U" is the internal energy, "p" is the pressure, and "V" is the volume. "G" is the most useful for processes involving a system at constant pressure "p" and temperature "T", because, in addition to subsuming any entropy change due merely to heat, a change in "G" also excludes the work needed to "make space for additional molecules" produced by various processes. Gibbs free energy change therefore equals work not associated with system expansion or compression, at constant temperature and pressure. (Hence its utility to solution-phase chemists, including biochemists.)


title: Thermodynamic free energy

text: The, historically earlier, Helmholtz free energy is defined in contrast as . Its change is equal to the amount of reversible work done on, or obtainable from, a system at constant "T". Thus its appellation "work content", and the designation "A" from "Arbeit", the German word for work. Since it makes no reference to any quantities involved in work (such as "p" and "V"), the Helmholtz function is completely general: its decrease is the maximum amount of work which can be done "by" a system at constant temperature, and it can increase at most by the amount of work done "on" a system isothermally. The Helmholtz free energy has a special theoretical importance since it is proportional to the logarithm of the partition function for the canonical ensemble in statistical mechanics. (Hence its utility to physicists; and to gas-phase chemists and engineers, who do not want to ignore work.)


title: Thermodynamic free energy

text: Historically, the term 'free energy' has been used for either quantity. In physics, "free energy" most often refers to the Helmholtz free energy, denoted by "A" (or "F"), while in chemistry, "free energy" most often refers to the Gibbs free energy. The values of the two free energies are usually quite similar and the intended free energy function is often implicit in manuscripts and presentations.


title: Thermodynamic free energy

text: The basic definition of "energy" is a measure of a body's (in thermodynamics, the system's) ability to cause change. For example, when a person pushes a heavy box a few metres forward, that person exerts mechanical energy, also known as work, on the box over a distance of a few meters forward. The mathematical definition of this form of energy is the product of the force exerted on the object and the distance by which the box moved (). Because the person changed the stationary position of the box, that person exerted energy on that box. The work exerted can also be called "useful energy", because energy was converted from one form into the intended purpose, i.e. mechanical utilisation. For the case of the person pushing the box, the energy in the form of internal (or potential) energy obtained through metabolism was converted into work in order to push the box. This energy conversion, however, was not straightforward: while some internal energy went into pushing the box, some was diverted away (lost) in the form of heat (transferred thermal energy). For a reversible process, heat is the product of the absolute temperature formula_1 and the change in entropy formula_2 of a body (entropy is a measure of disorder in a system). The difference between the change in internal energy, which is formula_3, and the energy lost in the form of heat is what is called the "useful energy" of the body, or the work of the body performed on an object. In thermodynamics, this is what is known as "free energy". In other words, free energy is a measure of work (useful energy) a system can perform at constant temperature. Mathematically, free energy is expressed as:


title: Thermodynamic free energy

text: This expression has commonly been interpreted to mean that work is extracted from the internal energy formula_5 while formula_6 represents energy not available to perform work. However, this is incorrect. For instance, in an isothermal expansion of an ideal gas, the internal energy change is formula_7 and the expansion work formula_8 is derived exclusively from the formula_6 term supposedly not available to perform work. But it is noteworthy that the derivative form of the free energy: formula_10 (for Helmholtz free energy) does indeed indicate that a spontaneous change in a non-reactive system's free energy (NOT the internal energy) comprises the available energy to do work (compression in this case) formula_11 and the unavailable energy formula_12. Similar expression can be written for the Gibbs free energy change.


title: Thermodynamic free energy

text: In the 18th and 19th centuries, the theory of heat, i.e., that heat is a form of energy having relation to vibratory motion, was beginning to supplant both the caloric theory, i.e., that heat is a fluid, and the four element theory, in which heat was the lightest of the four elements. In a similar manner, during these years, heat was beginning to be distinguished into different classification categories, such as “free heat”, “combined heat”, “radiant heat”, specific heat, heat capacity, “absolute heat”, “latent caloric”, “free” or “perceptible” caloric ("calorique sensible"), among others.


title: Thermodynamic free energy

text: In 1780, for example, Laplace and Lavoisier stated: “In general, one can change the first hypothesis into the second by changing the words ‘free heat, combined heat, and heat released’ into ‘vis viva, loss of vis viva, and increase of vis viva.’” In this manner, the total mass of caloric in a body, called "absolute heat", was regarded as a mixture of two components; the free or perceptible caloric could affect a thermometer, whereas the other component, the latent caloric, could not. The use of the words “latent heat” implied a similarity to latent heat in the more usual sense; it was regarded as chemically bound to the molecules of the body. In the adiabatic compression of a gas, the absolute heat remained constant but the observed rise in temperature implied that some latent caloric had become “free” or perceptible.


title: Thermodynamic free energy

text: During the early 19th century, the concept of perceptible or free caloric began to be referred to as “free heat” or heat set free. In 1824, for example, the French physicist Sadi Carnot, in his famous “Reflections on the Motive Power of Fire”, speaks of quantities of heat ‘absorbed or set free’ in different transformations. In 1882, the German physicist and physiologist Hermann von Helmholtz coined the phrase ‘free energy’ for the expression , in which the change in "A" (or "G") determines the amount of energy ‘free’ for work under the given conditions, specifically constant temperature.


title: Thermodynamic free energy

text: Thus, in traditional use, the term “free” was attached to Gibbs free energy for systems at constant pressure and temperature, or to Helmholtz free energy for systems at constant temperature, to mean ‘available in the form of useful work.’ With reference to the Gibbs free energy, we need to add the qualification that it is the energy free for non-volume work and compositional changes.


title: Thermodynamic free energy

text: An increasing number of books and journal articles do not include the attachment “free”, referring to "G" as simply Gibbs energy (and likewise for the Helmholtz energy). This is the result of a 1988 IUPAC meeting to set unified terminologies for the international scientific community, in which the adjective ‘free’ was supposedly banished. This standard, however, has not yet been universally adopted, and many published articles and books still include the descriptive ‘free’.


title: Thermodynamic free energy

text: Just like the general concept of energy, free energy has a few definitions suitable for different conditions. In physics, chemistry, and biology, these conditions are thermodynamic parameters (temperature formula_1, volume formula_14, pressure formula_15, etc.). Scientists have come up with several ways to define free energy. The mathematical expression of Helmholtz free energy is:


title: Thermodynamic free energy

text: This definition of free energy is useful for gas-phase reactions or in physics when modeling the behavior of isolated systems kept at a constant volume. For example, if a researcher wanted to perform a combustion reaction in a bomb calorimeter, the volume is kept constant throughout the course of a reaction. Therefore, the heat of the reaction is a direct measure of the free energy change, formula_17. In solution chemistry, on the other hand, most chemical reactions are kept at constant pressure. Under this condition, the heat formula_18 of the reaction is equal to the enthalpy change formula_19 of the system. Under constant pressure and temperature, the free energy in a reaction is known as Gibbs free energy formula_20.


title: Thermodynamic free energy

text: These functions have a minimum in chemical equilibrium, as long as certain variables (formula_1, and formula_14 or formula_15) are held constant. In addition, they also have theoretical importance in deriving Maxwell relations. Work other than may be added, e.g., for electrochemical cells, or work in elastic materials and in muscle contraction. Other forms of work which must sometimes be considered are stress-strain, magnetic, as in adiabatic demagnetization used in the approach to absolute zero, and work due to electric polarization. These are described by tensors.


title: Thermodynamic free energy

text: In most cases of interest there are internal degrees of freedom and processes, such as chemical reactions and phase transitions, which create entropy. Even for homogeneous "bulk" materials, the free energy functions depend on the (often suppressed) composition, as do all proper thermodynamic potentials (extensive functions), including the internal energy.


title: Thermodynamic free energy

text: formula_25 is the number of molecules (alternatively, moles) of type formula_26 in the system. If these quantities do not appear, it is impossible to describe compositional changes. The differentials for processes at uniform pressure and temperature are (assuming only formula_27 work):


title: Thermodynamic free energy

text: where "μ" is the chemical potential for the "i"th component in the system. The second relation is especially useful at constant formula_1 and formula_15, conditions which are easy to achieve experimentally, and which approximately characterize living creatures. Under these conditions, it simplifies to


title: Thermodynamic free energy

text: Any decrease in the Gibbs function of a system is the upper limit for any isothermal, isobaric work that can be captured in the surroundings, or it may simply be dissipated, appearing as formula_1 times a corresponding increase in the entropy of the system and/or its surrounding.


title: Thermodynamic free energy

text: An example is surface free energy, the amount of increase of free energy when the area of surface increases by every unit area.


title: Thermodynamic free energy

text: The path integral Monte Carlo method is a numerical approach for determining the values of free energies, based on quantum dynamical principles.


title: Thermodynamic free energy

text: This tells us that the change in free energy equals the reversible or maximum work for a process performed at constant temperature. Under other conditions, free-energy change is not equal to work; for instance, for a reversible adiabatic expansion of an ideal gas, Importantly, for a heat engine, including the Carnot cycle, the free-energy change after a full cycle is zero, while the engine produces nonzero work. It is important to note that for heat engines and other thermal systems, the free energies do not offer convenient characterizations; internal energy and enthalpy are the preferred potentials for characterizing thermal systems.


title: Thermodynamic free energy

text: According to the second law of thermodynamics, for any process that occurs in a closed system, the inequality of Clausius, Δ"S" > "q"/"T", applies. For a process at constant temperature and pressure without non-"PV" work, this inequality transforms into formula_35. Similarly, for a process at constant temperature and volume, formula_36. Thus, a negative value of the change in free energy is a necessary condition for a process to be spontaneous; this is the most useful form of the second law of thermodynamics in chemistry. In chemical equilibrium at constant "T" and "p" without electrical work, d"G" = 0.


title: Thermodynamic free energy

text: The quantity called "free energy" is a more advanced and accurate replacement for the outdated term "affinity", which was used by chemists in previous years to describe the "force" that caused chemical reactions. The term affinity, as used in chemical relation, dates back to at least the time of Albertus Magnus.


title: Thermodynamic free energy

text: From the 1998 textbook "Modern Thermodynamics" by Nobel Laureate and chemistry professor Ilya Prigogine we find: "As motion was explained by the Newtonian concept of force, chemists wanted a similar concept of ‘driving force’ for chemical change. Why do chemical reactions occur, and why do they stop at certain points? Chemists called the ‘force’ that caused chemical reactions affinity, but it lacked a clear definition."


title: Thermodynamic free energy

text: During the entire 18th century, the dominant view with regard to heat and light was that put forth by Isaac Newton, called the "Newtonian hypothesis", which states that light and heat are forms of matter attracted or repelled by other forms of matter, with forces analogous to gravitation or to chemical affinity.


title: Thermodynamic free energy

text: In the 19th century, the French chemist Marcellin Berthelot and the Danish chemist Julius Thomsen had attempted to quantify affinity using heats of reaction. In 1875, after quantifying the heats of reaction for a large number of compounds, Berthelot proposed the "principle of maximum work", in which all chemical changes occurring without intervention of outside energy tend toward the production of bodies or of a system of bodies which liberate heat.


title: Thermodynamic free energy

text: In addition to this, in 1780 Antoine Lavoisier and Pierre-Simon Laplace laid the foundations of thermochemistry by showing that the heat given out in a reaction is equal to the heat absorbed in the reverse reaction. They also investigated the specific heat and latent heat of a number of substances, and amounts of heat given out in combustion. In a similar manner, in 1840 Swiss chemist Germain Hess formulated the principle that the evolution of heat in a reaction is the same whether the process is accomplished in one-step process or in a number of stages. This is known as Hess' law. With the advent of the mechanical theory of heat in the early 19th century, Hess's law came to be viewed as a consequence of the law of conservation of energy.


title: Thermodynamic free energy

text: Based on these and other ideas, Berthelot and Thomsen, as well as others, considered the heat given out in the formation of a compound as a measure of the affinity, or the work done by the chemical forces. This view, however, was not entirely correct. In 1847, the English physicist James Joule showed that he could raise the temperature of water by turning a paddle wheel in it, thus showing that heat and mechanical work were equivalent or proportional to each other, i.e., approximately, . This statement came to be known as the mechanical equivalent of heat and was a precursory form of the first law of thermodynamics.


title: Thermodynamic free energy

text: By 1865, the German physicist Rudolf Clausius had shown that this equivalence principle needed amendment. That is, one can use the heat derived from a combustion reaction in a coal furnace to boil water, and use this heat to vaporize steam, and then use the enhanced high-pressure energy of the vaporized steam to push a piston. Thus, we might naively reason that one can entirely convert the initial combustion heat of the chemical reaction into the work of pushing the piston. Clausius showed, however, that we must take into account the work that the molecules of the working body, i.e., the water molecules in the cylinder, do on each other as they pass or transform from one step of or state of the engine cycle to the next, e.g., from (formula_37) to (formula_38). Clausius originally called this the “transformation content” of the body, and then later changed the name to entropy. Thus, the heat used to transform the working body of molecules from one state to the next cannot be used to do external work, e.g., to push the piston. Clausius defined this "transformation heat" as formula_39.


title: Thermodynamic free energy

text: In 1873, Willard Gibbs published "A Method of Geometrical Representation of the Thermodynamic Properties of Substances by Means of Surfaces", in which he introduced the preliminary outline of the principles of his new equation able to predict or estimate the tendencies of various natural processes to ensue when bodies or systems are brought into contact. By studying the interactions of homogeneous substances in contact, i.e., bodies, being in composition part solid, part liquid, and part vapor, and by using a three-dimensional volume-entropy-internal energy graph, Gibbs was able to determine three states of equilibrium, i.e., "necessarily stable", "neutral", and "unstable", and whether or not changes will ensue. In 1876, Gibbs built on this framework by introducing the concept of chemical potential so to take into account chemical reactions and states of bodies that are chemically different from each other. In his own words, to summarize his results in 1873, Gibbs states:


title: Thermodynamic free energy

text: In this description, as used by Gibbs, "ε" refers to the internal energy of the body, "η" refers to the entropy of the body, and "ν" is the volume of the body.


title: Thermodynamic free energy

text: Hence, in 1882, after the introduction of these arguments by Clausius and Gibbs, the German scientist Hermann von Helmholtz stated, in opposition to Berthelot and Thomas’ hypothesis that chemical affinity is a measure of the heat of reaction of chemical reaction as based on the principle of maximal work, that affinity is not the heat given out in the formation of a compound but rather it is the largest quantity of work which can be gained when the reaction is carried out in a reversible manner, e.g., electrical work in a reversible cell. The maximum work is thus regarded as the diminution of the free, or available, energy of the system (Gibbs free energy "G" at "T" = constant, "P" = constant or Helmholtz free energy "A" at "T" = constant, "V" = constant), whilst the heat given out is usually a measure of the diminution of the total energy of the system (Internal energy). Thus, "G" or "A" is the amount of energy “free” for work under the given conditions.


title: Thermodynamic free energy

text: Up until this point, the general view had been such that: “all chemical reactions drive the system to a state of equilibrium in which the affinities of the reactions vanish”. Over the next 60 years, the term affinity came to be replaced with the term free energy. According to chemistry historian Henry Leicester, the influential 1923 textbook "Thermodynamics and the Free Energy of Chemical Reactions" by Gilbert N. Lewis and Merle Randall led to the replacement of the term “affinity” by the term “free energy” in much of the English-speaking world.


title: Bit rate

text: In telecommunications and computing, bit rate (bitrate or as a variable "R") is the number of bits that are conveyed or processed per unit of time.


title: Bit rate

text: The bit rate is expressed in the unit bit per second (symbol: bit/s), often in conjunction with an SI prefix such as kilo (1 kbit/s = 1,000 bit/s), mega (1 Mbit/s = 1,000 kbit/s), giga (1 Gbit/s = 1,000 Mbit/s) or tera (1 Tbit/s = 1,000 Gbit/s). The non-standard abbreviation bps is often used to replace the standard symbol bit/s, so that, for example, 1 Mbps is used to mean one million bits per second.


title: Bit rate

text: In most computing and digital communication environments, one byte per second (symbol: B/s) corresponds to 8 bit/s.


title: Bit rate

text: When quantifying large or small bit rates, SI prefixes (also known as metric prefixes or decimal prefixes) are used, thus:


title: Bit rate

text: The International Standard (IEC 80000-13) specifies different abbreviations for binary and decimal (SI) prefixes (e.g. 1 KiB/s = 1024 B/s = 8192 bit/s, and 1 MiB/s = 1024 KiB/s).


title: Bit rate

text: In digital communication systems, the physical layer "gross bitrate", "raw bitrate", "data signaling rate", "gross data transfer rate" or "uncoded transmission rate" (sometimes written as a variable "R" or "f") is the total number of physically transferred bits per second over a communication link, including useful data as well as protocol overhead.


title: Bit rate

text: In case of serial communications, the gross bit rate is related to the bit transmission time formula_1


title: Bit rate

text: The gross bit rate is related to the symbol rate or modulation rate, which is expressed in bauds or symbols per second. However, the gross bit rate and the baud value are equal "only" when there are only two levels per symbol, representing 0 and 1, meaning that each symbol of a data transmission system carries exactly one bit of data; for example, this is not the case for modern modulation systems used in modems and LAN equipment.


title: Bit rate

text: More specifically, a line code (or baseband transmission scheme) representing the data using pulse-amplitude modulation with formula_4 different voltage levels, can transfer formula_5. A digital modulation method (or passband transmission scheme) using formula_4 different symbols, for example formula_4 amplitudes, phases or frequencies, can transfer formula_8. This results in:


title: Bit rate

text: An exception from the above is some self-synchronizing line codes, for example Manchester coding and return-to-zero (RTZ) coding, where each bit is represented by two pulses (signal states), resulting in:


title: Bit rate

text: A theoretical upper bound for the symbol rate in baud, symbols/s or pulses/s for a certain spectral bandwidth in hertz is given by the Nyquist law:


title: Bit rate

text: In practice this upper bound can only be approached for line coding schemes and for so-called vestigial sideband digital modulation. Most other digital carrier-modulated schemes, for example ASK, PSK, QAM and OFDM, can be characterized as double sideband modulation, resulting in the following relation:


title: Bit rate

text: where "n" is the number of parallel channels, "M" is the number of symbols or levels of the modulation in the "i"-th channel, and "T" is the symbol duration time, expressed in seconds, for the "i"-th channel.


title: Bit rate

text: The physical layer net bitrate, information rate, useful bit rate, payload rate, net data transfer rate, coded transmission rate, effective data rate or wire speed (informal language) of a digital communication channel is the capacity excluding the physical layer protocol overhead, for example time division multiplex (TDM) framing bits, redundant forward error correction (FEC) codes, equalizer training symbols and other channel coding. Error-correcting codes are common especially in wireless communication systems, broadband modem standards and modern copper-based high-speed LANs. The physical layer net bitrate is the datarate measured at a reference point in the interface between the datalink layer and physical layer, and may consequently include data link and higher layer overhead.


title: Bit rate

text: In modems and wireless systems, link adaptation (automatic adaption of the data rate and the modulation and/or error coding scheme to the signal quality) is often applied. In that context, the term peak bitrate denotes the net bitrate of the fastest and least robust transmission mode, used for example when the distance is very short between sender and transmitter. Some operating systems and network equipment may detect the "connection speed" (informal language) of a network access technology or communication device, implying the current net bit rate. Note that the term line rate in some textbooks is defined as gross bit rate, in others as net bit rate.


title: Bit rate

text: The relationship between the gross bit rate and net bit rate is affected by the FEC code rate according to the following.


title: Bit rate

text: The connection speed of a technology that involves forward error correction typically refers to the physical layer "net bit rate" in accordance with the above definition.


title: Bit rate

text: For example, the net bitrate (and thus the "connection speed") of an IEEE 802.11a wireless network is the net bit rate of between 6 and 54 Mbit/s, while the gross bit rate is between 12 and 72 Mbit/s inclusive of error-correcting codes.


title: Bit rate

text: The net bit rate of ISDN2 Basic Rate Interface (2 B-channels + 1 D-channel) of 64+64+16 = 144 kbit/s also refers to the payload data rates, while the D channel signalling rate is 16 kbit/s.


title: Bit rate

text: The net bit rate of the Ethernet 100Base-TX physical layer standard is 100 Mbit/s, while the gross bitrate is 125 Mbit/second, due to the 4B5B (four bit over five bit) encoding. In this case, the gross bit rate is equal to the symbol rate or pulse rate of 125 megabaud, due to the NRZI line code.


title: Bit rate

text: In communications technologies without forward error correction and other physical layer protocol overhead, there is no distinction between gross bit rate and physical layer net bit rate. For example, the net as well as gross bit rate of Ethernet 10Base-T is 10 Mbit/s. Due to the Manchester line code, each bit is represented by two pulses, resulting in a pulse rate of 20 megabaud.


title: Bit rate

text: The "connection speed" of a V.92 voiceband modem typically refers to the gross bit rate, since there is no additional error-correction code. It can be up to 56,000 bit/s downstreams and 48,000 bit/s upstreams. A lower bit rate may be chosen during the connection establishment phase due to adaptive modulationslower but more robust modulation schemes are chosen in case of poor signal-to-noise ratio. Due to data compression, the actual data transmission rate or throughput (see below) may be higher.


title: Bit rate

text: The channel capacity, also known as the Shannon capacity, is a theoretical upper bound for the maximum net bitrate, exclusive of forward error correction coding, that is possible without bit errors for a certain physical analog node-to-node communication link.


title: Bit rate

text: The channel capacity is proportional to the analog bandwidth in hertz. This proportionality is called Hartley's law. Consequently, the net bit rate is sometimes called digital bandwidth capacity in bit/s.


title: Bit rate

text: The term "throughput", essentially the same thing as digital bandwidth consumption, denotes the achieved average useful bit rate in a computer network over a logical or physical communication link or through a network node, typically measured at a reference point above the datalink layer. This implies that the throughput often excludes data link layer protocol overhead. The throughput is affected by the traffic load from the data source in question, as well as from other sources sharing the same network resources. See also measuring network throughput.


title: Bit rate

text: "Goodput" or data transfer rate refers to the achieved average net bit rate that is delivered to the application layer, exclusive of all protocol overhead, data packets retransmissions, etc. For example, in the case of file transfer, the goodput corresponds to the achieved file transfer rate. The file transfer rate in bit/s can be calculated as the file size (in bytes) divided by the file transfer time (in seconds) and multiplied by eight.


title: Bit rate

text: As an example, the goodput or data transfer rate of a V.92 voiceband modem is affected by the modem physical layer and data link layer protocols. It is sometimes higher than the physical layer data rate due to V.44 data compression, and sometimes lower due to bit-errors and automatic repeat request retransmissions.


title: Bit rate

text: If no data compression is provided by the network equipment or protocols, we have the following relation:


title: Bit rate

text: These are examples of physical layer net bit rates in proposed communication standard interfaces and devices:


title: Bit rate

text: In digital multimedia, bitrate represents the amount of information, or detail, that is stored per unit of time of a recording. The bitrate depends on several factors:


title: Bit rate

text: Generally, choices are made about the above factors in order to achieve the desired trade-off between minimizing the bitrate and maximizing the quality of the material when it is played.


title: Bit rate

text: If lossy data compression is used on audio or visual data, differences from the original signal will be introduced; if the compression is substantial, or lossy data is decompressed and recompressed, this may become noticeable in the form of compression artifacts. Whether these affect the perceived quality, and if so how much, depends on the compression scheme, encoder power, the characteristics of the input data, the listener's perceptions, the listener's familiarity with artifacts, and the listening or viewing environment.


title: Bit rate

text: The bitrates in this section are approximately the "minimum" that the "average" listener in a typical listening or viewing environment, when using the best available compression, would perceive as not significantly worse than the reference standard:


title: Bit rate

text: In digital multimedia, "bit rate" refers to the number of bits used per second to represent a continuous medium such as audio or video after source coding (data compression). The encoding bit rate of a multimedia file is its size in bytes divided by the playback time of the recording (in seconds), multiplied by eight.


title: Bit rate

text: For realtime streaming multimedia, the encoding bit rate is the goodput that is required to avoid interrupt:


title: Bit rate

text: The term average bitrate is used in case of variable bitrate multimedia source coding schemes. In this context, the peak bit rate is the maximum number of bits required for any short-term block of compressed data.


title: Bit rate

text: A theoretical lower bound for the encoding bit rate for lossless data compression is the source information rate, also known as the "entropy rate".


title: Bit rate

text: CD-DA, the standard audio CD, is said to have a data rate of 44.1 kHz/16, meaning that the audio data was sampled 44,100 times per second and with a bit depth of 16. CD-DA is also stereo, using a left and right channel, so the amount of audio data per second is double that of mono, where only a single channel is used.


title: Bit rate

text: For example, the bit rate of a CD-DA recording (44.1 kHz sampling rate, 16 bits per sample and two channels) can be calculated as follows:


title: Bit rate

text: The cumulative size of a length of PCM audio data (excluding a file header or other metadata) can be calculated using the following formula:


title: Bit rate

text: The cumulative size in bytes can be found by dividing the file size in bits by the number of bits in a byte, which is eight:


title: Bit rate

text: The MP3 audio format provides lossy data compression. Audio quality improves with increasing bitrate:


title: Bit rate

text: For technical reasons (hardware/software protocols, overheads, encoding schemes, etc.) the "actual" bit rates used by some of the compared-to devices may be significantly higher than what is listed above. For example, telephone circuits using µlaw or A-law companding (pulse code modulation) yield 64 kbit/s.


title: Breaststroke

text: Breaststroke is a swimming style in which the swimmer is on their chest and the torso does not rotate. It is the most popular recreational style due to the swimmer's head being out of the water a large portion of the time, and that it can be swum comfortably at slow speeds. In most swimming classes, beginners learn either the breaststroke or the freestyle (front crawl) first. However, at the competitive level, swimming breaststroke at speed requires endurance and strength comparable to other strokes. Some people refer to breaststroke as the "frog" stroke, as the arms and legs move somewhat like a frog swimming in the water. The stroke itself is the slowest of any competitive strokes and is thought to be the oldest of all swimming strokes.


title: Breaststroke

text: Breaststroke is the slowest of the four official styles in competitive swimming. The fastest breaststrokers can swim about 1.70 meters (~5.6 feet) per second. It is sometimes the hardest to teach to rising swimmers after butterfly due to the importance of timing and the coordination required to move the legs properly.


title: Breaststroke

text: In the breaststroke, the swimmer leans on the chest, arms breaking the surface of the water slightly, legs always underwater and the head underwater for the second half of the stroke. The kick is sometimes referred to as a "frog kick" because of the resemblance to the movement of a frog's hind legs; however, when done correctly it is more of a "whip kick" due to the whip-like motion that moves starting at the core down through the legs.


title: Breaststroke

text: The body is often at a steep angle to the forward movement, which slows down the swimmer more than any other style. Professional breaststrokers use abdominal muscles and hips to add extra power to the kick, although most do not perfect this technique until they are more experienced. This much faster form of breaststroke is referred to as "wave-action" breaststroke and fully incorporates the whip-kick.


title: Breaststroke

text: A special feature of competitive breaststroke is the underwater pullout. From the streamline position, one uses the arms to pull all the way down past the hips. As the arms are pulling down, one downward dolphin kick is allowed (as of the 2005 season), though still optional; more than one dolphin kick will result in disqualification. This is followed by the recovery of the arms to the streamline position once more with a breaststroke kick. The pullout is also called the "pull down". The pullout at the start and after the turns contributes significantly to the swimming times. Open turns can be easily performed at the walls, but both hands must make contact with the wall. Therefore, one way to improve swimming times is to focus on the start and the turns.


title: Breaststroke

text: The history of breaststroke goes back to the Stone Age, as for example pictures in the Cave of Swimmers near Wadi Sora in the southwestern part of Egypt near Libya. The leg action of the breaststroke may have originated by imitating the swimming action of frogs. Depictions of a variant of breaststroke are found in Babylonian bas-relief and Assyrian wall drawings.


title: Breaststroke

text: In 1538, Nicolas Wynman, a German professor of languages and poetry, wrote the first swimming book, "Colymbetes". His goal was not to promote exercise, but rather to reduce the dangers of drowning. Nevertheless, the book contained a good, methodical approach to learning breaststroke.


title: Breaststroke

text: In 1696, the French author and poet Melchisédech Thévenot wrote "The Art of Swimming", describing a breaststroke very similar to the modern breaststroke. The book (Benjamin Franklin became one of its readers) popularized this technique.


title: Breaststroke

text: In 1774, following a series of drownings, English physician John Zehr of the Society for the Recovery of Persons Apparently Drowned began giving public speeches and demonstrations to teach proper swimming technique. He is said to have helped to popularize breaststroke, noting the ease with which it could be learned and swum.


title: Breaststroke

text: In the pre-Olympic era, competitive swimming in Europe started around 1800, mostly using breaststroke. A watershed event was a swimming competition in 1844 in London, notable for the participation of some Native Americans. While the British raced using breaststroke, the Native Americans swam a variant of the front crawl. The British continued to swim only breaststroke until 1873.


title: Breaststroke

text: Captain Matthew Webb was the first man to swim the English channel (between England and France), in 1875. He used breaststroke, swimming 21.26 miles (34.21 km) in 21 hours and 45 minutes.


title: Breaststroke

text: The 1904 Summer Olympics in St. Louis, Missouri, were the first Olympics to feature a separate breaststroke competition, over a distance of 440 yards (402 m). These games differentiated breaststroke, backstroke, and freestyle.


title: Breaststroke

text: 1928 was the start of the scientific study of swimming by David Armbruster, coach at the University of Iowa, who filmed swimmers from underwater. One breaststroke problem Armbruster researched was that the swimmer was slowed down significantly while bringing the arms forward underwater. In 1934 Armbruster refined a method to bring the arms forward over water in breaststroke. While this "butterfly" technique was difficult, it brought a great improvement in speed. A year later, in 1935, Jack Sieg, a swimmer also from the University of Iowa, developed a technique involving swimming on his side and beating his legs in unison similar to a fish tail, and modified the technique afterward to swim it face down. Armbruster and Sieg combined these techniques into a variant of the breaststroke called butterfly, with the two kicks per cycle being called dolphin fishtail kick. Using this technique, Sieg swam 100 yards (91 m) in 1:00.2. However, even though this technique was much faster than regular breaststroke, the dolphin fishtail kick violated the rules. Butterfly arms with a breaststroke kick were used by a few swimmers in the 1936 Summer Olympics in Berlin for the breaststroke competitions. In 1938, almost every breaststroke swimmer was using this butterfly style, yet this stroke was considered a variant of the breaststroke until 1952, when it was accepted as a separate style with its own set of rules.


title: Breaststroke

text: In the early 1950s, another modification was developed for breaststroke. Breaking the water surface increases drag, reducing speed; swimming underwater increases speed. This led to a controversy at the 1956 Summer Olympics in Melbourne, when six swimmers were disqualified, as they repeatedly swam long distances underwater. However, a Japanese swimmer, Masaru Furukawa, circumvented the rule by not surfacing at all after the start, but swimming as much of the length underwater as possible before breaking the surface. He swam all but 5 m underwater for the first three 50 m lengths, and also swam half underwater for the last length, winning the gold medal. The adoption of this technique led to many swimmers suffering from oxygen starvation and even to some swimmers passing out during the race, so a new rule was introduced by the FINA, limiting the distance that can be swum underwater after the start and after every turn, and requiring the head to break the surface every cycle.


title: Breaststroke

text: Since then, the development of breaststroke has gone hand-in-hand with the FINA rules. In about the mid-1960s, the rules changed to prevent the arm stroke from going beyond the hip line, except during the first stroke after the start and after each turn. Before 1987, the head had to be kept above the water surface during the entire stroke. Later on, swimmers were also allowed to break the water with parts of the body other than the head. This led to a variant of the stroke in which the arms are brought together as usual under the body after the pull but then are thrown forward over the water from under the chin until the arms are completely extended. There was a controversy at the 2004 Summer Olympics at Athens after Japan's Kosuke Kitajima won the gold medal in the 100 m breaststroke race over American Brendan Hansen, the world-record-holder. Video from underwater cameras showed Kitajima using a dolphin kick at the start and at some of the turns. Officials claimed that these kicks were not visible from above the surface of the water, so the result stood. In July 2005, FINA announced a change of rules to allow one dolphin kick at the start and at each turn, the new rule took effect on 21 September 2005.


title: Breaststroke

text: The breaststroke starts with the fly high butterfly lying in the water face down, arms extended straight forward and legs extended straight to the back.


title: Breaststroke

text: There are three steps to the arm movement: outsweep, insweep, and recovery. The movement starts with the outsweep. From the streamline position, the palms turn out and the hands separate to slightly past shoulder width. The outsweep is followed by the insweep, where the hands point down and push the water backwards. The elbows stay in the horizontal plane through the shoulders. The hands push back until approximately the vertical plane through the shoulders. At the end of the insweep the hands come together with facing palms in front of the chest and the elbows are at the side at the body. In the recovery phase, the hands are moved forward again into the initial position under water. The entire arm stroke starts slowly, increases speed to the peak arm movement speed in the insweep phase, and slows down again during recovery. The goal is to produce maximum thrust during the insweep phase, and minimum drag during the recovery phase. Another variant is the underwater pull-down, similar to the push phase of a butterfly stroke. This stroke continues the insweep phase and pushes the hands all the way to the back to the sides of the hip. This greatly increases the push from one stroke, but also makes recovery more difficult. This style is well suited for underwater swimming. However, FINA allows this stroke only for the first stroke after the start and each turn. In late 2005, FINA has also introduced a new rule which permits a single downward kick after the push off the wall.


title: Breaststroke

text: As a variant, it is possible to recover the arms over water. This reduces drag, but requires more power. Some competitive swimmers use this variant in competition.


title: Breaststroke

text: The leg movement, colloquially known as the "frog kick" or "whip kick", consists of two phases: bringing the feet into position for the thrust phase and the insweep phase. From the initial position with the legs stretched out backward, the feet are moved together towards the posterior, while the knees stay together. The knees should not sink too low, as this increases the drag. Then the feet point outward in preparation for the thrust phase. In the thrust phase, the legs are moved elliptically back to the initial position. During this movement, the knees are kept together. The legs move slower while bringing the legs into position for the thrust phase, and move very fast during the thrust phase. Again, the goal is to produce maximum thrust during the insweep phase, and minimise drag during the recovery phase. In the recovery phase the lower leg and the feet are in the wake of the upper leg, and the feet are pointed to the rear. In the thrust phase all three parts create their own wake, and the flat end of the feet acts like a hydrofoil aligned to give maximum forward thrust. The resulting drag coefficient (or more precisely the frontal area) is thus doubled in the thrust phase.


title: Breaststroke

text: A fit adult creates a wake. Drag due to a wake is Newtonian drag, increasing with the square of the velocity. For example, if the relative speed between the water and the leg is twice as high on the thrust phase than on the recovery phase, the thrust is four times as high as the drag. Assuming the legs are recovered with a relative speed between leg and body which amounts to the same as the relative speed between water and body, the legs must be kicked back with five times the mean velocity of the swimmer. This limits the top speed. Both effects together, velocity and frontal area, yield a thrust-to-drag ratio of 8 for the legs.


title: Breaststroke

text: As a variant, some swimmers move the knees apart during the preparation phase and keep them apart until almost the end of the thrust phase. Moving both knee and foot outwards like a real frog avoids the extreme rotation in the lower leg.


title: Breaststroke

text: All other variants fail to increase the frontal area, yet swimmers using them still generate some thrust by the velocity variation and do not drown. Another variant of the breaststroke kick is the scissor kick, however, this kick violates the rules of the FINA as it is no longer symmetrical. Swimming teachers put a great effort into steering the students away from the scissor kick. In the scissor kick, one leg moves as described above, but the other leg does not form an elliptical movement but merely an up-down movement similar to the flutter kick of front crawl. Some swimming teachers believe that learning the front crawl first gives a higher risk of an incorrect scissor kick when learning breaststroke afterwards.


title: Breaststroke

text: Breaststroke can also be swum with the dolphin kick in butterfly, but this also violates the FINA rules. One kick is allowed, however, at the start and at the turn, providing that it is part of the body's natural movement.


title: Breaststroke

text: Humans have strong muscles in the legs and would need swim fins (like a frog) to bring all their power into the water and stand with the sole of the feet on the water. Rather the leg grabs almost as much water as the foot and a small amount of water is accelerated to high kinetic energy, but not much impulse is transferred. The toes are bent, the feet point 45° outwards, the sole points backwards, to mimic a hydrofoil. While closing in a V shape to the rear a small "lifting" force can be felt. Unlike in the other kicks, the joints are moved into extrema. Before the kick the knee is maximally bent and the upper leg is rotating along its axis to its extreme outer position and the lower leg is twisted to extreme, at the end of the kick the ankles are maximally turned to the inside so that the soles clap together to achieve a nozzle effect like in a jelly fish. Therefore, training involves getting flexible in addition to fitness and precision. The sudden sideways stress on the knees at the kick can lead to uncomfortable noise and feeling for the beginner and to wear for the senior.


title: Breaststroke

text: The easiest way to breathe during breaststroke is to let the head follow the spine. When the swimmer's elbows have reached the line of his eye and have begun to rise, his or her head starts to lift. If they uses their high elbows as a hinge for the inward sweep of their hands and forearms, they will create the leverage they need to use their abdominal muscles to bring their hips forward. When their hips move forward, their chest, shoulders and upper back will automatically lift up. Breathing is usually done during the beginning of the insweep phase of the arms, and the swimmer breathes in ideally through the mouth. The swimmer breathes out through mouth and nose during the recovery and gliding phase. Breaststroke can be swum faster if submerged completely, but FINA requires the head to break the surface once per cycle except for the first cycle after the start and each turn. Thus, competitive swimmers usually make one underwater pull-out, pushing the hands all the way to the back after the start and each turn.


title: Breaststroke

text: The movement starts in the initial position with the body completely straight. Body movement is coordinated such that the legs are ready for the thrust phase while the arms are halfway through the insweep, and the head is out of the water for breathing. In this position the body has also the largest angle to the horizontal. The arms are recovered during the thrust phase of the legs. After the stroke the body is kept in the initial position for some time to utilize the gliding phase. Depending on the distance and fitness the duration of this gliding phase varies. Usually the gliding phase is shorter during sprints than during long-distance swimming. The gliding phase is also longer during the underwater stroke after the start and each turn. However, the gliding phase is usually the longest phase in one entire cycle of breaststroke.


title: Breaststroke

text: Breaststroke uses the regular start for swimming. Some swimmers use a variant called the frog start, where the legs are pulled forward sharply before being extended again quickly during the airborne phase of the start. After the start a gliding phase follows under water, followed by one underwater pulldown and dolphin kick, then one whip kick as the hands are recovered back to a streamline. This is known as the pull-out. The head must break the surface before the arms reach their widest point on the first stroke after the pull-out. The downward butterfly kick was legalized by FINA, WWF and the NCAA in 2005, and remains optional. The downward fly kick is now allowed in MCSL.


title: Breaststroke

text: For competitive swimming it is important that the wall at the end of the lane is always touched by both hands (known as a "Two-Hand Touch") at the same time due to FINA regulations.


title: Breaststroke

text: The turn is initiated by touching the wall during the gliding or during the recovery phase of the arms, depending on how the wall can be touched faster. After touching the wall, the legs are pulled underneath the body. The body turns sideways while one hand is moved forward (i.e. towards the head) along the side of the body. When the body is almost completely turned, the other hand will be swung straight up through the air such that both hands meet at the front at the same time. At that time the body should also be almost in the horizontal and partially or totally submerged. After the body is completely submerged, the body is pushed off the wall with both legs. Doing this under water will reduce the drag. After a gliding phase, an underwater pull-out is done, followed by another gliding phase and then regular swimming. The head must break the surface during the second stroke.


title: Breaststroke

text: The three main styles of breaststroke seen today are the conventional (flat), undulating, and wave-style. The undulating style is usually swum by extremely flexible swimmers, (e.g. Amanda Beard), and few people have the flexibility to accomplish it. The wave-style breaststroke was pioneered by Hungarian Swimming Coach Joseph Nagy. The wave-style was swum and made famous by Mike Barrowman when he set a world record using it, and is now commonly swum by Olympians, though Australian swimmers, most prominently Leisel Jones, generally seem to shun it. Olympian Ed Moses still swims a flatter style, despite the rapidly increasing popularity of the wave-style.


title: Breaststroke

text: The wave-style breaststroke starts in a streamlined position, with shoulders shrugged to decrease drag in the water. While the conventional style is strongest at the outsweep, the wave-style puts much emphasis on the insweep, thus making the head rise later than in the conventional style. The wave-style pull is a circular motion with the hands accelerating to maximum speed and recovering in front of the chin, elbows staying at the surface and in front of the shoulders at all times. The high elbows creates the leverage for the powerful torso and abdominal muscles to assist in the stroke. During the insweep, the swimmer accelerates their hands and hollows their back and lifts themself out of the water to breathe. To visualize, some say that the hands anchor themselves in the water while the hips thrust forward.


title: Breaststroke

text: The hollowed back and accelerating hands would lift the head out of the water. The head stays in a neutral position, looking down and forward, and the swimmer inhales at this point. The feet retract to the bottom without moving the thigh, thus reducing resistance. The swimmer is at their highest at this point.


title: Breaststroke

text: Then the swimmer shrugs their shoulders and throws their arms and shoulders forward, lunging cat-like back into the water (though the emphasis is to go "forward", not down). As the swimmer sinks, they arch their back, and kick. Timing is very important in order for the kick to transfer all of its force via the arched back, but the optimum time is when the arms are 3/4 extended. Then the swimmer kicks and presses on their chest, undulating a little underwater, and squeezing the gluteus maximus to prevent the legs and feet from rising out of the water. The swimmer has now returned to the streamlined position, and the cycle starts again.


title: Breaststroke

text: Incidentally, the wave motion should not be overly emphasized and the swimmer should only rise until the water reaches his biceps, instead of pushing his entire torso out of the water, wasting a great deal of energy.


title: Breaststroke

text: There are eight common distances swum in competitive breaststroke swimming, four in yards and four in meters. Twenty-five-yard pools are common in the United States and are routinely used in age group, high school and college competitions during the winter months.


title: Breaststroke

text: Occasionally other distances are swum on an ad hoc, unofficial basis (such as 400 yd breaststroke in some college dual meets).


title: Breaststroke

text: SW 7.1 After the start and after each turn, the swimmer may take one arm stroke completely back to the legs during which the swimmer may be submerged. At any time prior to the first Breaststroke kick after the start and after each turn a single butterfly kick is permitted.


title: Breaststroke

text: SW 7.2 From the beginning of the first arm stroke after the start and after each turn, the body shall be on the breast. It is not permitted to roll onto the back at any time. From the start and throughout the race the stroke cycle must be one arm stroke and one leg kick in that order. All movements of the arms shall be simultaneous and on the same horizontal plane without alternating movement.


title: Breaststroke

text: SW 7.3 The hands shall be pushed forward together from the breast on, under, or over the water. The elbows shall be under water except for the final stroke before the turn, during the turn and for the final stroke at the finish. The hands shall be brought back on or under the surface of the water. The hands shall not be brought back beyond the hip line, except during the first stroke after the start and each turn.


title: Breaststroke

text: SW 7.4 During each complete cycle, some part of the swimmer's head must break the surface of the water. The head must break the surface of the water before the hands turn inward at the widest part of the second stroke. All movements of the legs shall be simultaneous and on the same horizontal plane without alternating movement.


title: Breaststroke

text: SW 7.5 The feet must be turned outwards during the propulsive part of the kick. A scissors, flutter or downward butterfly kick is not permitted except as in SW 7.1. Breaking the surface of the water with the feet is allowed unless followed by a downward butterfly kick.


title: Breaststroke

text: SW 7.6 At each turn and at the finish of the race, the touch shall be made with both hands simultaneously at, above, or below the water level. The head may be submerged after the last arm pull prior to the touch, provided it breaks the surface of the water at some point during the last complete or incomplete cycle preceding the touch.


title: Environmental effects of mining

text: Environmental effects of mining can occur at local, regional, and global scales through direct and indirect mining practices. The effects can result in erosion, sinkholes, loss of biodiversity, or the contamination of soil, groundwater, and surface water by the chemicals emitted from mining processes. These processes also affect the atmosphere from the emissions of carbon which have an effect on the quality of human health and biodiversity. Some mining methods (lithium mining, phosphate mining, coal mining, mountaintop removal mining, and sand mining) may have such significant environmental and public health effects that mining companies in some countries are required to follow strict environmental and rehabilitation codes to ensure that the mined area returns to its original state.


title: Environmental effects of mining

text: Erosion of exposed hillsides, mine dumps, tailings dams and resultant siltation of drainages, creeks and rivers can significantly affect the surrounding areas, a prime example being the giant Ok Tedi Mine in Papua New Guinea. Soil erosion can decrease the water availability for plant growth, resulting in a population decline in the plant ecosystem. Soil erosion is mainly caused by excessive rainfall, lack of soil management and chemical exposure from mining. In wilderness areas mining may cause destruction of ecosystems and habitats, and in areas of farming it may disturb or destroy productive grazing and croplands.


title: Environmental effects of mining

text: A sinkhole at or near a mine site is typically caused from the failure of a mine roof from the extraction of resources, weak overburden or geological discontinuities. The overburden at the mine site can develop cavities in the subsoil or rock, which can infill with sand and soil from the overlying strata. These cavities in the overburden have the potential to eventually cave in, forming a sinkhole at the surface. The sudden failure of earth creates a large depression at the surface without warning, this can be seriously hazardous to life and property. Sinkholes at a mine site can be mitigated with the proper design of infrastructure such as mining supports and better construction of walls to create a barrier around an area prone to sinkholes. Back-filling and grouting can be done to stabilize abandoned underground workings.


title: Environmental effects of mining

text: Mining can have harmful effects on surrounding surface and groundwater. If proper precautions are not taken, unnaturally high concentrations of chemicals, such as arsenic, sulphuric acid, and mercury can spread over a significant area of surface or subsurface water. Large amounts of water used for mine drainage, mine cooling, aqueous extraction and other mining processes increases the potential for these chemicals to contaminate ground and surface water. As mining produces copious amounts of waste water, disposal methods are limited due to contaminates within the waste water. Runoff containing these chemicals can lead to the devastation of the surrounding vegetation. The dumping of the runoff in surface waters or in a lot of forests is the worst option. Therefore, submarine tailings disposal are regarded as a better option (if the waste is pumped to great depth). Land storage and refilling of the mine after it has been depleted is even better, if no forests need to be cleared for the storage of debris. The contamination of watersheds resulting from the leakage of chemicals also has an effect on the health of the local population.


title: Environmental effects of mining

text: In well-regulated mines, hydrologists and geologists take careful measurements of water to take precaution to exclude any type of water contamination that could be caused by the mine's operations. The minimization of environmental degradation is enforced in American mining practices by federal and state law, by restricting operators to meet standards for the protection of surface and groundwater from contamination. This is best done through the use of non-toxic extraction processes as bioleaching.


title: Environmental effects of mining

text: Air pollutants have a negative impact on plant growth, primarily through interfering with resource accumulation. Once leaves are in close contact with the atmosphere, many air pollutants, such as O3 and NOx, affect the metabolic function of the leaves and interfere with net carbon fixation by the plant canopy. Air pollutants that are first deposited on the soil, such as heavy metals, first affect the functioning of roots and interfere with soil resource capture by the plant. These reductions in resource capture (production of carbohydrate through photosynthesis, mineral nutrient uptake and water uptake from the soil) will affect plant growth through changes in resource allocation to the various plant structures. When air pollution stress co-occurs with other stresses, e.g. water stress, the outcome on growth will depend on a complex interaction of processes within the plant. At the ecosystem level, air pollution can shift the competitive balance among the species present and may lead to changes in the composition of the plant community. In agroecosystems, these changes may be manifest in reduced economic yield.


title: Environmental effects of mining

text: Sub-surface mining often progresses below the water table, so water must be constantly pumped out of the mine in order to prevent flooding. When a mine is abandoned, the pumping ceases, and water floods the mine. This introduction of water is the initial step in most acid rock drainage situations.Acid rock drainage occurs naturally within some environments as part of the rock weathering process but is exacerbated by large-scale earth disturbances characteristic of mining and other large construction activities, usually within rocks containing an abundance of sulfide minerals. Areas where the earth has been disturbed (e.g. construction sites, subdivisions, and transportation corridors) may create acid rock drainage. In many localities, the liquid that drains from coal stocks, coal handling facilities, coal washeries, and coal waste tips can be highly acidic, and in such cases it is treated as acid mine drainage (AMD). The same type of chemical reactions and processes may occur through the disturbance of acid sulfate soils formed under coastal or estuarine conditions after the last major sea level rise, and constitutes a similar environmental hazard.


title: Environmental effects of mining

text: The five principal technologies used to monitor and control water flow at mine sites are diversion systems, containment ponds, groundwater pumping systems, subsurface drainage systems, and subsurface barriers. In the case of AMD, contaminated water is generally pumped to a treatment facility that neutralizes the contaminants. A 2006 review of environmental impact statements found that "water quality predictions made after considering the effects of mitigation largely underestimated actual impacts to groundwater, seeps, and surface water".


title: Environmental effects of mining

text: Heavy metals are naturally occurring elements that have a high atomic weight and a density at least 5 times greater than that of water. Their multiple industrial, domestic, agricultural, medical and technological applications have led to their wide distribution in the environment; raising concerns over their potential effects on human health and the environment.


title: Environmental effects of mining

text: Naturally occurring heavy metals are displayed in shapes that are not promptly accessible for uptake by plants. They are ordinarily displayed in insoluble shapes, like in mineral structures, or in precipitated or complex shapes that are not promptly accessible for plant take-up. Normally happening heavy metals have an awesome adsorption capacity in soil and are hence not promptly accessible for living organisms. The holding vitality between normally happening heavy metals and soil is exceptionally high compared to that with anthropogenic sources.


title: Environmental effects of mining

text: Dissolution and transport of metals and heavy metals by run-off and ground water is another example of environmental problems with mining, such as the Britannia Mine, a former copper mine near Vancouver, British Columbia. Tar Creek, an abandoned mining area in Picher, Oklahoma that is now an Environmental Protection Agency Superfund site, also suffers from heavy metal contamination. Water in the mine containing dissolved heavy metals such as lead and cadmium leaked into local groundwater, contaminating it. Long-term storage of tailings and dust can lead to additional problems, as they can be easily blown off site by wind, as occurred at Skouriotissa, an abandoned copper mine in Cyprus. Environmental changes such as global warming and increased mining activity may increase the content of heavy metals in the stream sediments.


title: Environmental effects of mining

text: The implantation of a mine is a major habitat modification, and smaller perturbations occur on a larger scale than exploitation site, mine-waste residuals contamination of the environment for example. Adverse effects can be observed long after the end of the mine activity. Destruction or drastic modification of the original site and anthropogenic substances release can have major impact on biodiversity in the area. Destruction of the habitat is the main component of biodiversity losses, but direct poisoning caused by mine-extracted material, and indirect poisoning through food and water, can also affect animals, vegetation and microorganisms. Habitat modification such as pH and temperature modification disturb communities in the surrounding area. Endemic species are especially sensitive, since they require very specific environmental conditions. Destruction or slight modification of their habitat put them at the risk of extinction. Habitats can be damaged when there is not enough terrestrial product as well as by non-chemical products, such as large rocks from the mines that are discarded in the surrounding landscape with no concern for impacts on natural habitat.


title: Environmental effects of mining

text: Concentrations of heavy metals are known to decrease with distance from the mine, and effects on biodiversity tend to follow the same pattern. Impacts can vary greatly depending on mobility and bioavailability of the contaminant: less-mobile molecules will stay inert in the environment while highly mobile molecules will easily move into another compartment or be taken up by organisms. For example, speciation of metals in sediments could modify their bioavailability, and thus their toxicity for aquatic organisms.


title: Environmental effects of mining

text: Biomagnification plays an important role in polluted habitats: mining impacts on biodiversity, assuming that concentration levels are not high enough to directly kill exposed organisms, should be greater to the species on top of the food chain because of this phenomenon.


title: Environmental effects of mining

text: Adverse mining effects on biodiversity depend a great extent on the nature of the contaminant, the level of concentration at which it can be found in the environment, and the nature of the ecosystem itself. Some species are quite resistant to anthropogenic disturbances, while some others will completely disappear from the contaminated zone. Time alone does not seem to allow the habitat to recover completely from the contamination. Remediation practices take time, and in most cases will not enable the recovery of the original diversity present before the mining activity took place.


title: Environmental effects of mining

text: The mining industry can impact aquatic biodiversity through different ways. One way can be direct poisoning; a higher risk for this occurs when contaminants are mobile in the sediment or bioavailable in the water. Mine drainage can modify water pH, making it hard to differentiate direct impact on organisms from impacts caused by pH changes. Effects can nonetheless be observed and proven to be caused by pH modifications. Contaminants can also affect aquatic organisms through physical effects: streams with high concentrations of suspended sediment limit light, thus diminishing algae biomass. Metal oxide deposition can limit biomass by coating algae or their substrate, thereby preventing colonization.


title: Environmental effects of mining

text: Factors that impact communities in acid mine drainage sites vary temporarily and seasonally: temperature, rainfall, pH, salinisation and metal quantity all display variations on the long term, and can heavily affect communities. Changes in pH or temperature can affect metal solubility, and thereby the bioavailable quantity that directly impact organisms. Moreover, contamination persists over time: ninety years after a pyrite mine closure, water pH was still very low and microorganisms populations consisted mainly of acidophil bacteria.


title: Environmental effects of mining

text: One big case study that was considered extremely toxic to aquatic organisms was the contamination that occurred in Minamata Bay. Methylmercury was released into wastewater by industrial chemical company's and a disease called Minamata disease was discovered in Kumamoto, Japan. This resulted in mercury poisoning in fishes and shellfishes and it was contaminating surrounding species and many died from it and it impacted anyone that ate the contaminated fishes.


title: Environmental effects of mining

text: Algae communities are less diverse in acidic water containing high zinc concentration, and mine drainage stress decrease their primary production. Diatoms' community is greatly modified by any chemical change, pH phytoplankton assemblage, and high metal concentration diminishes the abundance of planktonic species. Some diatom species may grow in high-metal-concentration sediments. In sediments close to the surface, cysts suffer from corrosion and heavy coating. In very polluted conditions, total algae biomass is quite low, and the planktonic diatom community is missing. Similarly to phytoplankton, the zooplankton communities are heavily altered in cases where the mining impact is severe. In case of functional complementary, however, it is possible that the phytoplankton and zooplankton mass remains stable.


title: Environmental effects of mining

text: Water insect and crustacean communities are modified around a mine, resulting in a low tropic completeness and their community being dominated by predators. However, biodiversity of macroinvertebrates can remain high, if sensitive species are replaced with tolerant ones. When diversity within the area is reduced, there is sometimes no effect of stream contamination on abundance or biomass, suggesting that tolerant species fulfilling the same function take the place of sensible species in polluted sites. pH diminution in addition to elevated metal concentration can also have adverse effects on macroinvertebrates' behaviour, showing that direct toxicity is not the only issue. Fish can also be affected by pH, temperature variations, and chemical concentrations.


title: Environmental effects of mining

text: Soil texture and water content can be greatly modified in disturbed sites, leading to plants community changes in the area. Most of the plants have a low concentration tolerance for metals in the soil, but sensitivity differs among species. Grass diversity and total coverage is less affected by high contaminant concentration than forbs and shrubs. Mine waste-materials rejects or traces due to mining activity can be found in the vicinity of the mine, sometimes far away from the source. Established plants cannot move away from perturbations, and will eventually die if their habitat is contaminated by heavy metals or metalloids at a concentration that is too elevated for their physiology. Some species are more resistant and will survive these levels, and some non-native species that can tolerate these concentrations in the soil, will migrate in the surrounding lands of the mine to occupy the ecological niche. This can also leave the soil vulnerable to potential soil erosion, which would make it inhabitable for plants.


title: Environmental effects of mining

text: Plants can be affected through direct poisoning, for example arsenic soil content reduces bryophyte diversity. Vegetation can also be contaminated from other metals as well such as nickel and copper. Soil acidification through pH diminution by chemical contamination can also lead to a diminished species number. Contaminants can modify or disturb microorganisms, thus modifying nutrient availability, causing a loss of vegetation in the area. Some tree roots divert away from deeper soil layers in order to avoid the contaminated zone, therefore lacking anchorage within the deep soil layers, resulting in the potential uprooting by the wind when their height and shoot weight increase. In general, root exploration is reduced in contaminated areas compared to non-polluted ones. Plant species diversity will remain lower in reclaimed habitats than in undisturbed areas. Depending on what specific type of mining is done, all vegetation can be initially removed from the area before the actual mining is started.


title: Environmental effects of mining

text: Cultivated crops might be a problem near mines. Most crops can grow on weakly contaminated sites, but yield is generally lower than it would have been in regular growing conditions. Plants also tend to accumulate heavy metals in their aerian organs, possibly leading to human intake through fruits and vegetables. Regular consumption of contaminated crops might lead to health problems caused by long-term metal exposure. Cigarettes made from tobacco growing on contaminated sites might also possibly have adverse effects on human population, as tobacco tends to accumulate cadmium and zinc in its leaves.


title: Environmental effects of mining

text: Habitat destruction is one of the main issues of mining activity. Huge areas of natural habitat are destroyed during mine construction and exploitation, forcing animals to leave the site.


title: Environmental effects of mining

text: Animals can be poisoned directly by mine products and residuals. Bioaccumulation in the plants or the smaller organisms they eat can also lead to poisoning: horses, goats and sheep are exposed in certain areas to potentially toxic concentration of copper and lead in grass. There are fewer ant species in soil containing high copper levels, in the vicinity of a copper mine. If fewer ants are found, chances are higher that other organisms living in the surrounding landscape are strongly affected by the high copper levels as well. Ants have good judgement whether an area is habitual as they live directly in the soil and are thus sensitive to environmental disruptions.


title: Environmental effects of mining

text: Microorganisms are extremely sensitive to environmental modification, such as modified pH, temperature changes or chemical concentrations due to their size. For example, the presence of arsenic and antimony in soils have led to diminution in total soil bacteria. Much like waters sensitivity, a small change in the soil pH can provoke the remobilization of contaminants, in addition to the direct impact on pH-sensitive organisms.


title: Environmental effects of mining

text: Microorganisms have a wide variety of genes among their total population, so there is a greater chance of survival of the species due to the resistance or tolerance genes in that some colonies possess, as long as modifications are not too extreme. Nevertheless, survival in these conditions will imply a big loss of gene diversity, resulting in a reduced potential for adaptations to subsequent changes. Undeveloped soil in heavy metal contaminated areas could be a sign of reduced activity by soils microfauna and microflora, indicating a reduced number of individuals or diminished activity. Twenty years after disturbance, even in rehabilitation area, microbial biomass is still greatly reduced compared to undisturbed habitat.


title: Environmental effects of mining

text: Arbuscular mycorrhiza fungi are especially sensitive to the presence of chemicals, and the soil is sometimes so disturbed that they are no longer able to associate with root plants. However, some fungi possess contaminant accumulation capacity and soil cleaning ability by changing the biodisponibility of pollutants, this can protect plants from potential damages that could be caused by chemicals. Their presence in contaminated sites could prevent loss of biodiversity due to mine-waste contamination, or allow for bioremediation, the removal of undesired chemicals from contaminated soils. On the contrary, some microbes can deteriorate the environment: which can lead to elevated SO4 in the water and can also increase microbial production of hydrogen sulfide, a toxin for many aquatic plants and organisms.


title: Environmental effects of mining

text: Mining processes produce an excess of waste materials known as tailings. The materials that are left over after are a result of separating the valuable fraction from the uneconomic fraction of ore. These large amounts of waste are a mixture of water, sand, clay, and residual bitumen. Tailings are commonly stored in tailings ponds made from naturally existing valleys or large engineered dams and dyke systems. Tailings ponds can remain part of an active mine operation for 30–40 years. This allows for tailings deposits to settle, or for storage and water recycling.


title: Environmental effects of mining

text: Tailings have great potential to damage the environment by releasing toxic metals by acid mine drainage or by damaging aquatic wildlife; these both require constant monitoring and treatment of water passing through the dam. However, the greatest danger of tailings ponds is dam failure. Tailings ponds are typically formed by locally derived fills (soil, coarse waste, or overburden from mining operations and tailings) and the dam walls are often built up on to sustain greater amounts of tailings. The lack of regulation for design criteria of the tailings ponds are what put the environment at risk for flooding from the tailings ponds.


title: Environmental effects of mining

text: A spoil tip is a pile of accumulated overburden that was removed from a mine site during the extraction of coal or ore. These waste materials are composed of ordinary soil and rocks, with the potential to be contaminated with chemical waste


title: Environmental effects of mining

text: . Spoil is much different from tailings, as it is processed material that remains after the valuable components have been extracted from ore. Spoil tip combustion can happen fairly commonly as, older spoil tips tend to be loose and tip over the edge of a pile. As spoil is mainly composed of carbonaceous material that is highly combustible, it can be accidentally ignited by the lighting fire or the tipping of hot ashes. Spoil tips can often catch fire and be left burning underground or within the spoil piles for many years.


title: Environmental effects of mining

text: Mining activities, including prospecting, exploration, construction, operation, maintenance, expansion, abandonment, decommissioning and repurposing of a mine can impact social and environmental systems in a range of positive and negative, and direct and indirect ways.


title: Environmental effects of mining

text: Humans are also affected by mining. There are many diseases that can come from the pollutants that are released into the air and water during the mining process. For example, during smelting operations large quantities of air pollutants, such as the suspended particulate matter, SO, arsenic particles and cadmium, are emitted. Metals are usually emitted into the air as particulates as well. There are also many occupational health hazards that miners face. Most of miners suffer from various respiratory and skin diseases such as asbestosis, silicosis, or black lung disease.


title: Environmental effects of mining

text: Furthermore, one of the biggest subset of mining that impacts humans is the pollutants that end up in the water, which results in poor water quality. About 30% of the world has access to renewable freshwater which is used by industries that generate large amounts of waste containing chemicals in various concentrations that are deposited into the freshwater. The concern of active chemicals in the water can pose a great risk to human health as it can accumulate within the water and fishes. There was a study done on an abandon mine in China, Dabaoshan mine and this mine was not active to many years yet the impact of how metals can accumulate in water and soil was a major concern for neighboring villages. Due to the lack of proper care of waste materials 56% of mortality rate is estimated within the regions around this mining sites, and many have been diagnosed with esophageal cancer and liver cancer. It resulted that this mine till this day still has negative impacts on human health through crops and it is evident that there needs to be more cleaning up measures around surrounding areas.


title: Environmental effects of mining

text: The long-term effects associated with air pollution are plenty including chronic asthma, pulmonary insufficiency, and cardiovascular mortality. According to a Swedish cohort study, diabetes seems to be induced after long-term air pollution exposure. Furthermore, air pollution seems to have various malign health effects in early human life, such as respiratory, cardiovascular, mental, and perinatal disorders, leading to infant mortality or chronic disease in adult age. Discuss contamination basically influences those living in huge urban zones, where street outflows contribute the foremost to the degradation of discuss quality. There's moreover a threat of mechanical mishaps, where the spread of a harmful haze can be lethal to the populaces of the encompassing regions. The scattering of poisons is decided by numerous parameters, most outstandingly barometrical soundness and wind.


title: Environmental effects of mining

text: With open cast mining the overburden, which may be covered in forest, must be removed before the mining can commence. Although the deforestation due to mining may be small compared to the total amount it may lead to species extinction if there is a high level of local endemism.


title: Environmental effects of mining

text: The lifecycle of mining coal is one of the filthiest cycles that causes deforestation due to the amount of toxins, and heavy metals that are released soil and water environment. Although the effects of coal mining take a long time to impact the environment the burning of coals and fires which can burn up to decades can release flying ash and increase the greenhouse gasses. Specifically strip mining that can destroy landscapes, forests, and wildlife habitats that are near the sites. Trees, plants and topsoil are cleared from the mining area and this can lead to destruction of agricultural land. Furthermore, when rainfall occurs the ashes and other materials are washed into streams that can hurt fish. These impacts can still occur after the mining site is completed which disturbs the presences of the land and restoration of the deforestation takes longer than usual because the quality of the land is degraded. Legal mining, albeit more environmentally-controlled than illegal mining, contributes to some substantial percentage to the deforestation of tropical countries


title: Environmental effects of mining

text: The environmental factors of the coal industry are not only impacting air pollution, water management and land use but also is causing severe health effects by the burning of the coal. Air pollution is increasing in numbers of toxins such as mercury, lead, sulfur dioxide, nitrogen oxides and other heavy metals. This is causing health issues involving breathing difficulties and is impacting the wildlife around the surrounding areas that needs clean air to survive. The future of air pollution remains unclear as the Environmental Protection Agency have tried to prevent some emissions but don't have control measures in place for all plants producing mining of coal. Water pollution is another factor that is being damaged throughout this process of mining coals, the ashes from coal is usually carried away in rainwater which streams into larger water sites. It can take up to 10 years to clean water sites that have coal waste and the potential of damaging clean water can only make the filtration much more difficult.


title: Environmental effects of mining

text: Deep sea mining for manganese nodules and other resources have led to concerns from marine scientists and environmental groups over the impact on fragile deep sea ecosystems. Knowledge of potential impacts is limited due to limited research on deep sea life.


title: Environmental effects of mining

text: Lithium does not occur as the metal naturally since it is highly reactive, but is found combined in small amounts in rocks, soils, and bodies of water. The extraction of lithium in rock form can be exposed to air, water, and soil. Furthermore, batteries are globally demanded for containing lithium in regards to manufacturing, the toxic chemicals that lithium produce can negatively impact humans, soils, and marine species. Lithium production increased by 25% between 2000 and 2007 for the use of batteries, and the major sources of lithium are found in brine lake deposits. Lithium is discovered and extracted from 150 minerals, clays, numerous brines, and sea water, and although lithium extraction from rock-form is twice as expensive from that of lithium extracted from brines, the average brine deposit is greater than in comparison to an average lithium hard rock deposit.


title: Environmental effects of mining

text: Phosphate-bearing rocks are mined to produce phosphorus, an essential element used in industry and agriculture. The process of extraction includes removal of surface vegetation, thereby exposing phosphorus rocks to the terrestrial ecosystem, damaging the land area with exposed phosphorus, resulting in ground erosion. The products released from phosphate ore mining are wastes, and tailings, resulting in human exposure to particulate matter from contaminated tailings via inhalation and the toxic elements that impact human health are (Cd, Cr, Zn, Cu and Pb).


title: Environmental effects of mining

text: Oil shale is a sedimentary rock containing kerogen which hydrocarbons can be produced. Mining oil shale impacts the environment it can damage the biological land and ecosystems. The thermal heating and combustion generate a lot of material and waste that includes carbon dioxide and greenhouse gas. Many environmentalists are against the production and usage of oil shale because it creates large amounts of greenhouse gasses. Among air pollution, water contamination is a huge factor mainly because oil shales are dealing with oxygen and hydrocarbons. There is changes in the landscape with mining sites due to oil shale mining and the production using chemical products. The ground movements within the area of underground mining is a problem that is long-term because it causes non-stabilized areas. Underground mining causes a new formation that can be suitable for some plant growth, but rehabilitation could be required.