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Saline water

Saline water is water that contains a high concentration of dissolved salts. The salt concentration is expressed in parts per thousand or parts per million; the United States Geological Survey classifies saline water in three salinity categories. Salt concentration in saline water is around 1,000 to 3,000 ppm, in moderately saline water 3,000 to 10,000 ppm and in saline water 10,000 to 35,000 ppm. Seawater has a salinity of 35,000 ppm, equivalent to 35 grams of salt per one liter of water; the saturation level is dependent on the temperature of the water. At 20 °C one liter of water can dissolve about 357 grams of salt, a concentration of 26.3% w/v. At boiling the amount that can be dissolved in one liter of water increases to about 391 grams, a concentration of 28.1% w/v. Some industries make use such as mining and thermo-electric power. At 100 °C, saturated sodium chloride brine is about 28% salt by weight. At 0 °C, brine can only hold about 26% salt. At 20 °C one liter of water can dissolve about 357 grams of salt, a concentration of 26.3%.

The thermal conductivity of seawater is 0.6 W/mK at 25 °C. The thermal conductivity decreases with increasing salinity and increases with increasing temperature; the graphs and online calculations in this page plot thermal conductivity for varying salinity and temperature:The salt content can be determined with a salinometer. Density ρ of brine at various concentrations and temperatures can be approximated with a linear equation: ρ = a 3 − where the values of an are: About four percent of hydrogen gas produced worldwide is created by electrolysis; the majority of this hydrogen produced through electrolysis is a side product in the production of chlorine. 2 NaCl + 2 H2O → 2 NaOH + H2 + Cl2 Brackish water Brine Salinity Seawater Media related to Saline water at Wikimedia Commons

Chris Evans (British politician)

Christopher James Evans is a Labour Co-operative politician in the United Kingdom, the Member of Parliament for Islwyn since 2010. Chris Evans was brought up in the Rhondda valleys, he graduated with a history degree from Carmarthen. At the age of 13 he suffered a serious leg injury in a road traffic collision and underwent months of recovery: he stated that the experience, on top of the stress caused by his parents' divorce, had caused him to develop body dysmorphic disorder. Before being elected to Parliament he worked as a bookmaker, in a bank and as a trade union official, he worked as a parliamentary researcher to then-Islwyn MP Don Touhig for four years. He lost. However, at the 2010 general election he was elected MP for the safe Labour seat of Islwyn, his maiden speech focused on affordable pay day loans. Since being elected he has campaigned against fuel poverty and in January 2011 led a Westminster Hall debate and spoke out against energy price rises, he is a campaigner for the introduction of a Presumption of Death Act.

He led a Westminster Hall debate on employment opportunities for people with inflammatory bowel disease. Evans is a member of the Justice Select Committee. In July 2012, after two years as an MP, he was promoted to the Shadow Department of Environment and Rural Affairs as Parliamentary Private Secretary to shadow Secretary of State Mary Creagh Following a reshuffle in October 2013, Evans joined Labour's Shadow Treasury Team as Parliamentary Private Secretary to Chief Secretary to the Treasury, Chris Leslie, he supported Owen Smith in the failed attempt to replace Jeremy Corbyn in the 2016 Labour Party leadership election. On 19 January 2012, Evans revealed that he had been attacked by a dog which left a one-inch scar on his middle finger as he called on the government to take action against irresponsible dog owners. Since he has been campaigning to promote responsible dog ownership. In May 2012 he held a Westminster Hall debate on dangerous dog legislation and called on the government to introduce the compulsory microchipping of all dogs, recorded by a single national database.

In March 2012 Evans introduced a ten-minute rule bill called'The Banking Responsibility and Disclosure Bill' which aimed to tackle the growing problem of financial exclusion to ensure that banks are responsible for their actions. He has written several articles on this topic. In 2013 Evans launched a work experience program in Islwyn to help combat the problem of youth unemployment. Working alongside 200 local businesses, the scheme offers 6–8 week work placements for 18- to 24-year-olds out of work. Unlike government schemes the Islwyn Work Experience Programme is voluntary with applicants receiving additional help from Job Centre Plus to continue looking for permanent work It was launched alongside local businesses at a media event at the Crosskeys campus of Coleg Gwent. In December 2013, Evans married Julia Ockenden, a former head of public affairs at the BBC. Profile at Parliament of the United Kingdom Contributions in Parliament at Hansard Voting record at Public Whip Record in Parliament at TheyWorkForYou Profile at Westminster Parliamentary Record

Time crystal

A time crystal or space-time crystal is a structure that repeats in time, as well as in space. Normal three-dimensional crystals have a repeating pattern in space, but remain unchanged as time passes. Time crystals repeat themselves in time as well, leading the crystal to change from moment to moment. If a discrete time translation symmetry is broken the system is referred to as a discrete time crystal. A discrete time crystal never reaches thermal equilibrium, as it is a type of non-equilibrium matter, a form of matter proposed in 2012, first observed in 2017; the idea of a quantum time crystal was first described by Nobel laureate Frank Wilczek in 2012. Work developed a more precise definition for time crystals, it was proven. In 2014 Krzysztof Sacha predicted the behavior of discrete time crystals in a periodically-driven many-body system, and in 2016, Norman Yao et al. proposed a different way to create discrete time crystals in spin systems. From there, Christopher Monroe and Mikhail Lukin independently confirmed this in their labs.

Both experiments were published in Nature in 2017. In 2019 it was theoretically proven that a quantum time crystal can be realized in isolated systems with long range multi-particle interactions; the idea of a space-time crystal was first put forward by Frank Wilczek, a professor at MIT and Nobel laureate, in 2012. In 2013, Xiang Zhang, a nanoengineer at University of California and his team proposed creating a time crystal in the form of a rotating ring of charged ions. In response to Wilczek and Zhang, Patrick Bruno, a theorist at the European Synchrotron Radiation Facility in Grenoble, published several articles in 2013 claiming to show that space-time crystals were impossible. Masaki Oshikawa from the University of Tokyo showed that time crystals would be impossible at their ground state. Subsequent work developed more precise definitions of time translation symmetry-breaking, which led to a "no-go" proof that quantum time crystals in equilibrium are not possible. Several realizations of time crystals, which avoid the equilibrium no-go arguments, were proposed.

Krzysztof Sacha at Jagiellonian University in Krakow predicted the behaviour of discrete time crystals in a periodically driven system of ultracold atoms. Works suggested that periodically driven quantum spin systems could show similar behaviour. Norman Yao at Berkeley studied a different model of time crystals, his ideas were used by two teams: a group led by Harvard's Mikhail Lukin and a group led by Christopher Monroe at University of Maryland. Symmetries in nature lead directly to conservation laws, something, formulated by the Noether theorem; the basic idea of time-translation symmetry is that a translation in time has no effect on physical laws, i.e. that the laws of nature that apply today were the same in the past and will be the same in the future. This symmetry implies the conservation of energy. Normal crystals exhibit broken translation symmetry: they have repeated patterns in space and are not invariant under arbitrary translations or rotations; the laws of physics are unchanged by arbitrary rotations.

However, if we hold fixed the atoms of a crystal, the dynamics of an electron or other particle in the crystal depend on how it moves relative to the crystal, particle momentum can change by interacting with the atoms of a crystal — for example in Umklapp processes. Quasimomentum, however, is conserved in a perfect crystal. Time crystals show a broken symmetry analogous to a discrete space-translation symmetry breaking. For example, the molecules of a liquid freezing on the surface of a crystal can align with the molecules of the crystal, but with a pattern less symmetric than the crystal: it breaks the initial symmetry; this broken symmetry exhibits three important characteristics: the system has a lower symmetry than the underlying arrangement of the crystal, the system exhibits spatial and temporal long-range order, it is the result of interactions between the constituents of the system, which aligns themselves relative to each other. Time crystals seem to break time-translation symmetry and have repeated patterns in time if the laws of the system are invariant by translation of time.

Studied time crystals shows discrete time-translation symmetry breaking: they are periodically driven systems oscillating at a fraction of the frequency of the driving force. The initial symmetry is a discrete time-translation symmetry, not a continuous one, which are instead described by magnetic space groups. Many systems can show behaviors of spontaneous time translation symmetry breaking: convection cells, oscillating chemical reactions, aerodynamic flutter, subharmonic response to a periodic driving force such as the Faraday instability, NMR spin echos, parametric down-conversion, period-doubled nonlinear dynamical systems. However, Floquet time crystals are unique in that they follow a strict definition of discrete time-translation symmetry breaking: it is a broken symmetry – the system shows oscillations with a period longer than the driving force, the system is in crypto-equilibrium – these oscillations generate no entropy, a time-dependant frame can be found in which the system is indistinguishable from an equilibrium when measured stroboscopically (which i