United States Patent and Trademark Office
The United States Patent and Trademark Office is an agency in the U. S. Department of Commerce that issues patents to inventors and businesses for their inventions, trademark registration for product and intellectual property identification; the USPTO is "unique among federal agencies because it operates on fees collected by its users, not on taxpayer dollars". Its "operating structure is like a business in that it receives requests for services—applications for patents and trademark registrations—and charges fees projected to cover the cost of performing the services provide"; the USPTO is based in Alexandria, after a 2005 move from the Crystal City area of neighboring Arlington, Virginia. The offices under Patents and the Chief Information Officer that remained just outside the southern end of Crystal City completed moving to Randolph Square, a brand-new building in Shirlington Village, on April 27, 2009; the current Under Secretary of Commerce for Intellectual Property and Director of the USPTO is Andrei Iancu.
He began his role as Director on February 8, 2018. Iancu was nominated by President Trump in August 2017, unanimously confirmed by the U. S. Senate. Prior to joining the USPTO, he was the Managing Partner at Irell & Manella LLP, where his practice focused on intellectual property litigation; the USPTO cooperates with the European Patent Office and the Japan Patent Office as one of the Trilateral Patent Offices. The USPTO is a Receiving Office, an International Searching Authority and an International Preliminary Examination Authority for international patent applications filed in accordance with the Patent Cooperation Treaty; the USPTO maintains a permanent, interdisciplinary historical record of all U. S. patent applications in order to fulfill objectives outlined in the United States Constitution. The legal basis for the United States patent system is Article 1, Section 8, wherein the powers of Congress are defined, it states, in part: The Congress shall have Power... To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries.
The PTO's mission is to promote "industrial and technological progress in the United States and strengthen the national economy" by: Administering the laws relating to patents and trademarks. The USPTO is headquartered at the Alexandria Campus, consisting of 11 buildings in a city-like development surrounded by ground floor retail and high rise residential buildings between the Metro stations of King Street station and Eisenhower Avenue station where the actual Alexandria Campus is located between Duke Street to Eisenhower Avenue, between John Carlyle Street to Elizabeth Lane in Alexandria, Virginia. An additional building in Arlington, was opened in 2009; the USPTO was expected by 2014 to open its first satellite offices in Detroit, Dallas and Silicon Valley to reduce backlog and reflect regional industrial strengths. The first satellite office opened in Detroit on July 13, 2012. In 2013, due to the budget sequestration, the satellite office for Silicon Valley, home to one of the nation's top patent-producing cities, was put on hold.
However and infrastructure updates continued after the sequestration, the Silicon Valley location opened in the San Jose City Hall in 2015. As of September 30, 2009, the end of the U. S. government's fiscal year, the PTO had 9,716 employees, nearly all of whom are based at its five-building headquarters complex in Alexandria. Of those, 6,242 were patent examiners and 388 were trademark examining attorneys. While the agency has noticeably grown in recent years, the rate of growth was far slower in fiscal 2009 than in the recent past. Patent examiners make up the bulk of the employees at USPTO, they hold degrees in various scientific disciplines, but do not hold law degrees. Unlike patent examiners, trademark examiners must be licensed attorneys. All examiners work under a strict, "count"-based production system. For every application, "counts" are earned by composing and mailing a first office action on the merits, upon disposal of an application; the Commissioner for Patents oversees three main bodies, headed by former Deputy Commissioner for Patent Operations Peggy Focarino, the Deputy Commissioner for Patent Examination Policy Andrew Hirshfeld as Acting Deputy, the Commissioner for Patent Resources and Planning, vacant.
The Patent Operations of the office is divided into nine different technology centers that deal with various arts. Prior to 2012, decisions of patent examiners may be appealed to the Board of Patent Appeals and Interferences, an administrative law body of the USPTO. Decisions of the BPAI could further be appealed to the United States Court of Appeals for the Federal Circuit, or a civil suit may be brought against the Commissioner of Patents in the United States District Court for the Eastern District of Virginia; the United States Supreme Court may decide on a patent case. Under the America Invents Act, the BPAI was converted to the Patent Trial and Appeal Board or "PTAB". Simila
Long Island is a densely populated island off the East Coast of the United States, beginning at New York Harbor 0.35 miles from Manhattan Island and extending eastward into the Atlantic Ocean. The island comprises four counties in the U. S. state of New York. Kings and Queens Counties and Nassau County share the western third of the island, while Suffolk County occupies the eastern two-thirds. More than half of New York City's residents now live in Brooklyn and Queens. However, many people in the New York metropolitan area colloquially use the term Long Island to refer to Nassau and Suffolk Counties, which are suburban in character, conversely employing the term the City to mean Manhattan alone. Broadly speaking, "Long Island" may refer both to the main island and the surrounding outer barrier islands. North of the island is Long Island Sound, across which lie Westchester County, New York, the state of Connecticut. Across the Block Island Sound to the northeast is the state of Rhode Island. To the west, Long Island is separated from the island of Manhattan by the East River.
To the extreme southwest, it is separated from Staten Island and the state of New Jersey by Upper New York Bay, the Narrows, Lower New York Bay. To the east lie Block Island—which belongs to the State of Rhode Island—and numerous smaller islands. Both the longest and the largest island in the contiguous United States, Long Island extends 118 miles eastward from New York Harbor to Montauk Point, with a maximum north-to-south distance of 23 miles between Long Island Sound and the Atlantic coast. With a land area of 1,401 square miles, Long Island is the 11th-largest island in the United States and the 149th-largest island in the world—larger than the 1,214 square miles of the smallest U. S. state, Rhode Island. With a Census-estimated population of 7,869,820 in 2017, constituting nearly 40% of New York State's population, Long Island is the most populated island in any U. S. state or territory, the 18th-most populous island in the world. Its population density is 5,595.1 inhabitants per square mile.
If Long Island geographically constituted an independent metropolitan statistical area, it would rank fourth most populous in the United States. S. state, Long Island would rank 13th in population and first in population density. Long Island is culturally and ethnically diverse, featuring some of the wealthiest and most expensive neighborhoods in the Western Hemisphere near the shorelines as well as working-class areas in all four counties; as a hub of commercial aviation, Long Island contains two of the New York City metropolitan area's three busiest airports, JFK International Airport and LaGuardia Airport, in addition to Islip MacArthur Airport. Nine bridges and 13 tunnels connect Brooklyn and Queens to the three other boroughs of New York City. Ferries connect Suffolk County northward across Long Island Sound to the state of Connecticut; the Long Island Rail Road is the busiest commuter railroad in North America and operates 24/7. Nassau County high school students feature prominently as winners of the Intel International Science and Engineering Fair and similar STEM-based academic awards.
Biotechnology companies and scientific research play a significant role in Long Island's economy, including research facilities at Brookhaven National Laboratory, Cold Spring Harbor Laboratory, Plum Island Animal Disease Center, State University of New York at Stony Brook, the New York University Tandon School of Engineering, the City University of New York, Hofstra Northwell School of Medicine. Prior to European contact, the Lenape people inhabited the western end of Long Island, spoke the Munsee dialect of Lenape, one of the Algonquian language family. Giovanni da Verrazzano was the first European to record an encounter with the Lenapes, after entering what is now New York Bay in 1524; the eastern portion of the island was inhabited by speakers of the Mohegan-Montauk-Narragansett language group of Algonquian languages. In 1609, the English navigator Henry Hudson explored the harbor and purportedly landed at Coney Island. Adriaen Block followed in 1615, is credited as the first European to determine that both Manhattan and Long Island are islands.
Native American land deeds recorded by the Dutch from 1636 state that the Indians referred to Long Island as Sewanhaka. Sewan was one of the terms for wampum, is translated as "loose" or "scattered", which may refer either to the wampum or to Long Island; the name "'t Lange Eylandt alias Matouwacs" appears in Dutch maps from the 1650s. The English referred to the land as "Nassau Island", after the Dutch Prince William of Nassau, Prince of Orange, it is unclear. Another indigenous name from colonial time, comes from the Native American name for Long Island and means "the island that pays tribute." The first settlements on Long Island were by settlers from England and its colonies in present-day New England. Lion Gardiner settled nearby Gardiners Island. T
New Jersey is a state in the Mid-Atlantic and Northeastern regions of the United States. It is located on a peninsula, bordered on the north and east by the state of New York along the extent of the length of New York City on its western edge. New Jersey is the fourth-smallest state by area but the 11th-most populous, with 9 million residents as of 2017, the most densely populated of the 50 U. S. states. New Jersey lies within the combined statistical areas of New York City and Philadelphia. New Jersey was the second-wealthiest U. S. state by median household income as of 2017. New Jersey was inhabited by Native Americans for more than 2,800 years, with historical tribes such as the Lenape along the coast. In the early 17th century, the Dutch and the Swedes founded the first European settlements in the state; the English seized control of the region, naming it the Province of New Jersey after the largest of the Channel Islands and granting it as a colony to Sir George Carteret and John Berkeley, 1st Baron Berkeley of Stratton.
New Jersey was the site of several decisive battles during the American Revolutionary War in the 18th century. In the 19th century, factories in cities, Paterson, Trenton, Jersey City, Elizabeth helped to drive the Industrial Revolution. New Jersey's geographic location at the center of the Northeast megalopolis, between Boston and New York City to the northeast, Philadelphia and Washington, D. C. to the southwest, fueled its rapid growth through the process of suburbanization in the second half of the 20th century. In the first decades of the 21st century, this suburbanization began reverting with the consolidation of New Jersey's culturally diverse populace toward more urban settings within the state, with towns home to commuter rail stations outpacing the population growth of more automobile-oriented suburbs since 2008. Around 180 million years ago, during the Jurassic Period, New Jersey bordered North Africa; the pressure of the collision between North America and Africa gave rise to the Appalachian Mountains.
Around 18,000 years ago, the Ice Age resulted in glaciers. As the glaciers retreated, they left behind Lake Passaic, as well as many rivers and gorges. New Jersey was settled by Native Americans, with the Lenni-Lenape being dominant at the time of contact. Scheyichbi is the Lenape name for the land, now New Jersey; the Lenape were several autonomous groups that practiced maize agriculture in order to supplement their hunting and gathering in the region surrounding the Delaware River, the lower Hudson River, western Long Island Sound. The Lenape society was divided into matrilinear clans; these clans were organized into three distinct phratries identified by their animal sign: Turtle and Wolf. They first encountered the Dutch in the early 17th century, their primary relationship with the Europeans was through fur trade; the Dutch became the first Europeans to lay claim to lands in New Jersey. The Dutch colony of New Netherland consisted of parts of modern Middle Atlantic states. Although the European principle of land ownership was not recognized by the Lenape, Dutch West India Company policy required its colonists to purchase the land that they settled.
The first to do so was Michiel Pauw who established a patronship called Pavonia in 1630 along the North River which became the Bergen. Peter Minuit's purchase of lands along the Delaware River established the colony of New Sweden; the entire region became a territory of England on June 24, 1664, after an English fleet under the command of Colonel Richard Nicolls sailed into what is now New York Harbor and took control of Fort Amsterdam, annexing the entire province. During the English Civil War, the Channel Island of Jersey remained loyal to the British Crown and gave sanctuary to the King, it was from the Royal Square in Saint Helier that Charles II of England was proclaimed King in 1649, following the execution of his father, Charles I. The North American lands were divided by Charles II, who gave his brother, the Duke of York, the region between New England and Maryland as a proprietary colony. James granted the land between the Hudson River and the Delaware River to two friends who had remained loyal through the English Civil War: Sir George Carteret and Lord Berkeley of Stratton.
The area was named the Province of New Jersey. Since the state's inception, New Jersey has been characterized by religious diversity. New England Congregationalists settled alongside Scots Presbyterians and Dutch Reformed migrants. While the majority of residents lived in towns with individual landholdings of 100 acres, a few rich proprietors owned vast estates. English Quakers and Anglicans owned large landholdings. Unlike Plymouth Colony and other colonies, New Jersey was populated by a secondary wave of immigrants who came from other colonies instead of those who migrated directly from Europe. New Jersey remained agrarian and rural throughout the colonial era, commercial farming developed sporadically; some townships, such as Burlington on the Delaware River and Perth Amboy, emerged as important ports for shipping to New York City and Philadelphia. The colony's fertile lands and tolerant religious policy drew more settlers, New Jersey's population had increased to 120,000 by 1775. Settlement for the first 10 years of English rule took place along Hackensack River and Arthur Kill –
A booby trap is a device or setup, intended to kill, harm, or surprise a person or animal, unknowingly triggered by the presence or actions of the victim. As the word trap implies, they sometimes have some form of bait designed to lure the victim towards it. At other times, the trap is set to act upon trespassers that violate restricted areas; the device can be triggered when the victim performs some type of everyday action, e.g. opening a door, picking something up, or switching something on. They can be triggered by vehicles driving along a road, as in the case of victim-operated improvised explosive devices. Booby traps should not be confused with mantraps. Lethal booby traps are used in warfare guerrilla warfare, traps designed to cause injury or pain are sometimes used by criminals wanting to protect drugs or other illicit property, by some owners of legal property who wish to protect it from theft. Booby traps which cause discomfort or embarrassment are a popular form of practical joke.
The Spanish word bobo translates to "stupid, daft, naïve, fool, clown, funny man, one, cheated" and similar pejorative terms. The slang of bobo, translates to "dunce". Variations of this word exist in other languages, with their meaning being "to stammer". Thus, the term "booby trap" gives rise to the idea that an individual with the misfortune to be caught in the trap does so because the individual is a "booby", or that an individual, caught in the trap thereby becomes a "booby"; the word has been applied to the sea bird genus Sula, with their common name being boobies. These birds, adapted for sea flight and swimming, have large flat feet and wide wingspans, making it difficult for them to run or take flight quickly; as a result, they are considered easy to catch when onshore. They are known for landing aboard seagoing vessels, whereupon they have been eaten by the crew. In 1590, the word began appearing in the English language as booby, meaning "stupid person, slow bird"; the phrase booby trap applied to schoolboy pranks, but took on its more sinister connotation during World War I.
A military booby trap may be designed to kill or injure a person who activates its trigger, or employed to reveal the location of an enemy by setting off a signalling device. Most, but not all, military booby traps involve explosives. There is no clear division between a booby trap and buried conventional land mines triggered by a tripwire or directional mine. Other, similar devices include spring-guns and mechanisms such as the SM-70 directional antipersonnel mine. What distinguishes a booby trap is that its activation is intended to be unexpected to its victim, thus booby trap design is varied, with traps or their trigger mechanisms hidden. At least part of the device is improvised from standard ordnance, such as an artillery shell, grenade, or high explosive. However, some mines have features designed for incorporation into booby traps and armies have been equipped with a variety of mass-produced triggering mechanisms intended to be employed in booby traps deployment. Part of the skill in placing booby traps lies in exploiting natural human behaviors such as habit, self-preservation, curiosity or acquisitiveness.
A common trick is to provide victims with a simple solution to a problem, for example, leaving only one door open in an otherwise secure building, thereby luring them straight toward the firing mechanism. An example that exploits an instinct for self-preservation was used in the Vietnam War. Spikes known as Punji sticks were hidden in grassy areas; when fired upon soldiers instinctively sought to take cover by throwing themselves down on the ground, impaling themselves on the spikes. Attractive or interesting objects are used as bait. For example, troops could leave behind empty beer bottles and a sealed wooden packing case with "Scotch Whisky" marked on it before leaving an area; the rubble-filled packing case might be resting on top of an M5 or M142 firing device, connected to some blocks of TNT or to some C4 explosive stuffed into the empty fuze pocket of a mortar shell. Alternatively, the weight of the packing case might be holding down the arming lever of an RGD-5 grenade with a zero-delay fuze fitted and the pin removed.
Either way, when the case is moved. Many different types of bait object can be used e.g. soldiers will be tempted to kick an empty beer can lying on the ground as they walk past it. However, the can may be resting on top of an M5 pressure-release firing device screwed into a buried M26 grenade. Many purpose-built booby-trap firing devices exist such as the versatile M142 universal firing device, or Yugoslavian UMNOP-1 which allow a variety of different ways of triggering explosives e.g. via trip wire, direct pressure on an object, or pressure release etc. Any item can be booby-trapped in some way. For example, booby trapping a flashlight is a classic tactic: a flashlight contains most of the required components. First of all, tempting the victim to pick it up. More it is easy to conceal a detonator, some explosives, batteries inside the flashlight casing. A simple electrical circuit is connected to the on/off switch; when the victim attempts to turn the flashlight on to see if it works, the resulting explosion blows their hand or arm off and blinds them.
The only limits to the i
Huntington, New York
The Town of Huntington is one of ten towns in Suffolk County, New York, United States. Founded in 1653, it is located on the north shore of Long Island in northwestern Suffolk County, with Long Island Sound to its north and Nassau County adjacent to the west. Huntington is part of the New York metropolitan area; as of the United States 2010 Census, the town population was 203,264. In 1653, three men from Oyster Bay, Richard Holbrook, Robert Williams and Daniel Whitehead, purchased a parcel of land from the Matinecock tribe; this parcel has since come to be known as the "First Purchase" and included land bordered by Cold Spring Harbor on the west, Northport Harbor on the east, what is now known as Old Country Road to the south and Long Island Sound to the north. The three men turned the land over to the settlers, living there. From that initial settlement, Huntington grew over subsequent years to include all of the land presently comprising the modern Towns of Huntington and Babylon; the southern part of the town was formally separated to create Babylon in 1872.
Because Huntington was populated by English settlers, unlike the rest of the New Amsterdam colony, the town voted in 1660 to become part of the Connecticut colony rather than remain under the authority of New Amsterdam. It was not until the British gained control of New Amsterdam in 1664 that Huntington was formally restored to the jurisdiction of New York. Following the Battle of Long Island during the American Revolutionary War, British troops used Huntington as their headquarters, remained encamped there until the end of the war; the arrival of the Long Island Rail Road in 1867 transformed the economy of Huntington from agriculture and shipping to tourism and commuting. Cold Spring Harbor became a popular summer resort; the end of World War II brought about an explosive growth of population in Huntington, as in the rest of the region. Farms and resorts gave way to homes, Huntington has transformed into a major bedroom community for nearby New York City; as of the census of 2000, there were 195,289 people, 65,917 households, 52,338 families residing in the town.
The population density was 2,078.4 people per square mile. There were 67,708 housing units at an average density of 720.6 per square mile. The racial makeup of the town in 2000 was 88.31% White, 4.22% Black or African American, 0.13% Native American, 3.50% Asian, 0.02% Pacific Islander, 2.27% from other races, 1.55% from two or more races. Hispanic or Latino of any race were 6.58% of the population. As of the census of 2010, the racial makeup of the town was 84.15% White, 4.68% Black or African American, 0.20% Native American, 4.96% Asian, 0.02% Pacific Islander, 3.89% from other races, 2.10% from two or more races. Hispanic or Latino of any race were 11.00% of the population. There were 65,917 households out of which 37.1% had children under the age of 18 living with them, 67.4% were married couples living together, 8.9% had a female householder with no husband present, 20.6% were non-families. 16.2% of all households were made up of individuals and 6.7% had someone living alone, 65 years of age or older.
The average household size was 2.91 and the average family size was 3.26. In the town, the population was spread out with 25.5% under the age of 18, 5.8% from 18 to 24, 30.2% from 25 to 44, 25.5% from 45 to 64, 13.1% who were 65 years of age or older. The median age was 39 years. For every 100 females, there were 96.2 males. For every 100 females age 18 and over, there were 93.4 males. According to a 2007 estimate, the median income for a household in the town was $102,865, the median income for a family was $113,119. Males had a median income of $61,748 versus $40,825 for females; the per capita income for the town was $36,390. About 2.9% of families and 4.6% of the population were below the poverty line, including 5.1% of those under age 18 and 4.6% of those age 65 or over. The town government consists of a town council with four members; the town supervisor is elected by the entire town. Other elected positions are the Town Clerk, Highway Superintendent, Receiver of Taxes. A referendum to move to a ward district system on December 22, 2009 failed 81% to 18%.
Sbarro's headquarters were located in Melville in the Town of Huntington until 2015. Around 2002, Swiss International Air Lines's North American headquarters moved from Melville to Uniondale, Town of Hempstead; the facility, the former Swissair North American headquarter site, was completed in 1995. Swissair intended to own, instead of lease, its headquarters site, it enlisted architect Richard Meier to design the Melville facility. In 1997, Aer Lingus announced that it was moving its North American headquarters from Manhattan to Melville; the move would transfer 75 employees, including administrative personnel, marketing personnel, sales personnel, telephone reservation agents. The airline planned to move on June 15, 1997; the airline had considered sites in Boston and in Westchester, New York. According to Huntington's 2016 Comprehensive Annual Financial Report, the top employers in the town are: Huntington is home to two colleges and universities, including: Five Towns College in Dix Hills Seminary of the Immaculate Conception There are a number of notable schools in Huntington.
Several weekly newspapers cover local news including The Long-Islander, since 1838 as well as The Times of Huntington by TBR News Media. The Village Connection Magazine, published by Jim Savalli, is a lifestyle and ente
A solvent is a substance that dissolves a solute, resulting in a solution. A solvent is a liquid but can be a solid, a gas, or a supercritical fluid; the quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Common uses for organic solvents are in dry cleaning, as paint thinners, as nail polish removers and glue solvents, in spot removers, in detergents and in perfumes. Water is a solvent for the most common solvent used by living things. Solvents find various applications in chemical, pharmaceutical and gas industries, including in chemical syntheses and purification processes; when one substance is dissolved into another, a solution is formed. This is opposed to the situation. In a solution, all of the ingredients are uniformly distributed at a molecular level and no residue remains. A solvent-solute mixture consists of a single phase with all solute molecules occurring as solvates, as opposed to separate continuous phases as in suspensions and other types of non-solution mixtures.
The ability of one compound to be dissolved in another is known as solubility. In addition to mixing, the substances in a solution interact with each other at the molecular level; when something is dissolved, molecules of the solvent arrange around molecules of the solute. Heat transfer is involved and entropy is increased making the solution more thermodynamically stable than the solute and solvent separately; this arrangement is mediated by the respective chemical properties of the solvent and solute, such as hydrogen bonding, dipole moment and polarizability. Solvation does not cause a chemical chemical configuration changes in the solute. However, solvation resembles a coordination complex formation reaction with considerable energetics and is thus far from a neutral process. Solvents can be broadly classified into two categories: non-polar. A special case is mercury; the dielectric constant of the solvent provides a rough measure of a solvent's polarity. The strong polarity of water is indicated by its high dielectric constant of 88.
Solvents with a dielectric constant of less than 15 are considered to be nonpolar. The dielectric constant measures the solvent's tendency to cancel the field strength of the electric field of a charged particle immersed in it; this reduction is compared to the field strength of the charged particle in a vacuum. Heuristically, the dielectric constant of a solvent can be thought of as its ability to reduce the solute's effective internal charge; the dielectric constant of a solvent is an acceptable predictor of the solvent's ability to dissolve common ionic compounds, such as salts. Dielectric constants are not the only measure of polarity; because solvents are used by chemists to carry out chemical reactions or observe chemical and biological phenomena, more specific measures of polarity are required. Most of these measures are sensitive to chemical structure; the Grunwald–Winstein mY scale measures polarity in terms of solvent influence on buildup of positive charge of a solute during a chemical reaction.
Kosower's Z scale measures polarity in terms of the influence of the solvent on UV-absorption maxima of a salt pyridinium iodide or the pyridinium zwitterion. Donor number and donor acceptor scale measures polarity in terms of how a solvent interacts with specific substances, like a strong Lewis acid or a strong Lewis base; the Hildebrand parameter is the square root of cohesive energy density. It can not accommodate complex chemistry. Reichardt's dye, a solvatochromic dye that changes color in response to polarity, gives a scale of ET values. ET is the transition energy between the ground state and the lowest excited state in kcal/mol, identifies the dye. Another correlated scale can be defined with Nile red; the polarity, dipole moment and hydrogen bonding of a solvent determines what type of compounds it is able to dissolve and with what other solvents or liquid compounds it is miscible. Polar solvents dissolve polar compounds best and non-polar solvents dissolve non-polar compounds best: "like dissolves like".
Polar compounds like sugars or ionic compounds, like inorganic salts dissolve only in polar solvents like water, while non-polar compounds like oils or waxes dissolve only in non-polar organic solvents like hexane. Water and hexane are not miscible with each other and will separate into two layers after being shaken well. Polarity can be separated to different contributions. For example, the Kamlet-Taft parameters are dipolarity/polarizability, hydrogen-bonding acidity and hydrogen-bonding basicity; these can be calculated from the wavelength shifts of 3–6 different solvatochromic dyes in the solvent including Reichardt's dye and diethylnitroaniline. Another option, Hansen's parameters, separate the cohesive energy density into dispersion and hydrogen bonding contributions. Solvents with a dielectric constant (more relative
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains high concentration of ozone in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere; the ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is about 0.3 parts per million. The ozone layer is found in the lower portion of the stratosphere, from 15 to 35 kilometers above Earth, although its thickness varies seasonally and geographically; the ozone layer was discovered in 1913 by the French physicists Charles Henri Buisson. Measurements of the sun showed that the radiation sent out from its surface and reaching the ground on Earth is consistent with the spectrum of a black body with a temperature in the range of 5,500–6,000 K, except that there was no radiation below a wavelength of about 310 nm at the ultraviolet end of the spectrum.
It was deduced. The spectrum of the missing radiation was matched to only one known chemical, ozone, its properties were explored in detail by the British meteorologist G. M. B. Dobson, who developed a simple spectrophotometer that could be used to measure stratospheric ozone from the ground. Between 1928 and 1958, Dobson established a worldwide network of ozone monitoring stations, which continue to operate to this day; the "Dobson unit", a convenient measure of the amount of ozone overhead, is named in his honor. The ozone layer absorbs 97 to 99 percent of the Sun's medium-frequency ultraviolet light, which otherwise would damage exposed life forms near the surface. In 1976 atmospheric research revealed that the ozone layer was being depleted by chemicals released by industry chlorofluorocarbons. Concerns that increased UV radiation due to ozone depletion threatened life on Earth, including increased skin cancer in humans and other ecological problems, led to bans on the chemicals, the latest evidence is that ozone depletion has slowed or stopped.
The United Nations General Assembly has designated September 16 as the International Day for the Preservation of the Ozone Layer. Venus has a thin ozone layer at an altitude of 100 kilometers from the planet's surface; the photochemical mechanisms that give rise to the ozone layer were discovered by the British physicist Sydney Chapman in 1930. Ozone in the Earth's stratosphere is created by ultraviolet light striking ordinary oxygen molecules containing two oxygen atoms, splitting them into individual oxygen atoms; the ozone molecule is unstable and when ultraviolet light hits ozone it splits into a molecule of O2 and an individual atom of oxygen, a continuing process called the ozone-oxygen cycle. Chemically, this can be described as: O2 + ℎνuv → 2 O O + O2 ↔️ O3About 90 percent of the ozone in the atmosphere is contained in the stratosphere. Ozone concentrations are greatest between about 20 and 40 kilometres, where they range from about 2 to 8 parts per million. If all of the ozone were compressed to the pressure of the air at sea level, it would be only 3 millimetres thick.
Although the concentration of the ozone in the ozone layer is small, it is vitally important to life because it absorbs biologically harmful ultraviolet radiation coming from the sun. Short or vacuum UV is screened out by nitrogen. UV radiation capable of penetrating nitrogen is divided into three categories, based on its wavelength. UV-C, harmful to all living things, is screened out by a combination of dioxygen and ozone by around 35 kilometres altitude. UV-B radiation is the main cause of sunburn; the ozone layer is effective at screening out UV-B. Some UV-B at its longest wavelengths, reaches the surface, is important for the skin's production of vitamin D. Ozone is transparent to most UV-A, so most of this longer-wavelength UV radiation reaches the surface, it constitutes most of the UV reaching the Earth; this type of UV radiation is less harmful to DNA, although it may still cause physical damage, premature aging of the skin, indirect genetic damage, skin cancer. The thickness of the ozone layer varies worldwide and is thinner near the equator and thicker near the poles.
Thickness refers to how much ozone is in a column over a given area and varies from season to season. The reasons for these variations are due to solar intensity; the majority of ozone is produced over the tropics and is transported towards the poles by stratospheric wind patterns. In the northern hemisphere these patterns, known as the Brewer-Dobson circulation, make the ozone layer thickest in the spring and thinnest in the fall; when ozone in produced by solar UV radiation in the tropics, it is done so by circulation lifting ozone-poor air out of the troposphere and into the stratospher