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Thomas Midgley, Jr
Thomas Midgley Jr. (May 18, 1889 – November 2, 1944) was an American mechanical and chemical engineer. He played a major role in developing leaded gasoline (tetraethyl lead) and some of the first chlorofluorocarbons (CFCs), better known in the United States by the brand name Freon; both products were later banned from common use due to their harmful impact on human health and the environment. He was granted more than 100 patents over the course of his career. Midgley contracted polio in 1940 and was left disabled; in 1944, he was found strangled to death by a device he devised to allow him to get out of bed unassisted. It is often reported that he had been accidentally killed by his own invention, but his death was declared by the coroner to be a suicide. While the harmful effects of CFCs were not appreciated until decades after Midgley's death, tetraethyl lead was known to be acutely toxic by those involved in the development of leaded gasoline. This included Midgley, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beaver Falls, Pennsylvania
Beaver Falls is a city in Beaver County, Pennsylvania, United States. The population was 9,005 at the 2020 United States census, 2020 census. Located 31 miles (50 km) northwest of Pittsburgh, the city lies along the Beaver River (Pennsylvania), Beaver River, six miles (9 km) north of its confluence with the Ohio River. It is a part of the Pittsburgh metropolitan area. History The area of present-day Beaver Falls was first mentioned in 1770 in the journals of David Zeisberger, a Moravian Church missionary who eventually settled in present-day Lawrence County, Pennsylvania, Lawrence County. A Lenape chief named Custaloga, Pakanke took Zeisberger to the valley surrounding the Beaver River (Pennsylvania), Beaver River, where the Lenape owned a large tract of open land which Zeisberger was given access to. In April 1770, Zeisberger and his followers set out in 16 canoes down the Allegheny River, Allegheny and Ohio River, Ohio rivers, reaching the mouth of the Beaver three d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Impact On The Environment
Human impact on the environment (or anthropogenic environmental impact) refers to changes to biophysical environments and to ecosystems, biodiversity, and natural resources caused directly or indirectly by humans. Modifying the environment to fit the needs of society (as in the built environment) is causing severe effects including global warming, environmental degradation (such as ocean acidification), mass extinction and biodiversity loss, ecological crisis, and ecological collapse. Some human activities that cause damage (either directly or indirectly) to the environment on a global scale include population growth, neoliberal economic policies and rapid economic growth, overconsumption, overexploitation, pollution, and deforestation. Some of the problems, including global warming and biodiversity loss, have been proposed as representing catastrophic risks to the survival of the human species. The term ''anthropogenic'' designates an effect or object resulting from h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periodic Table
The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows (" periods") and columns (" groups"). It is an icon of chemistry and is widely used in physics and other sciences. It is a depiction of the periodic law, which states that when the elements are arranged in order of their atomic numbers an approximate recurrence of their properties is evident. The table is divided into four roughly rectangular areas called blocks. Elements in the same group tend to show similar chemical characteristics. Vertical, horizontal and diagonal trends characterize the periodic table. Metallic character increases going down a group and from right to left across a period. Nonmetallic character increases going from the bottom left of the periodic table to the top right. The first periodic table to become generally accepted was that of the Russian chemist Dmitri Mendeleev in 1869; he formulated the periodic law as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baseball (ball)
A baseball is the ball used in the sport of baseball. It consists of a rubber or cork center wrapped in yarn and covered with white natural horsehide or cowhide, or a synthetic composite leather. A regulation baseball is in circumference i.e. in diameter, with a weight of . The leather cover is commonly formed from two saddle-shaped pieces stitched together, typically with red-dyed thread. There are 108 stitches on a regulation baseball. That stitching plays a significant role in the trajectory of a thrown baseball due to the drag caused by the interaction between the stitching and the air. Controlling the orientation of the stitches and the speed of the ball's rotation allows a pitcher to affect the behavior of the pitched ball in specific ways. Commonly employed pitches include the curveball, the slider, the two-seam fastball, the four-seam fastball, the sinker, the cutter and the changeup. History In the early, mid-1800s days of baseball, there was a great variety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High School In The United States
High school or senior high school is the education students receive in the final stage of secondary education in the United States. In the United States, most high schoolers are ages 14–18, but some ages could be delayed due to how their birthday coincides with the academic calendar. Most comparable to secondary schools, high schools generally deliver phase three of the International Standard Classification of Education, ISCED model of education. High schools have subject-based classes. The name high school is applied in other countries, but no universal generalization can be made as to the age range, financial status, or ability level of the pupils accepted. In North America, most high schools include grades 9 through 12. Students attend them following graduation from middle school (often alternatively called junior high school). History As late as 1900, high school attendance was very rare in the United States, with only a small percentage of the population ever attending h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Inventors Hall Of Fame
The National Inventors Hall of Fame (NIHF) is an American not-for-profit organization, founded in 1973, which recognizes individual engineers and inventors who hold a US patent of significant technology. Besides the Hall of Fame, it also operates a museum in Alexandria, Virginia, sponsors educational programs, and a collegiate competition. As of 2025, 652 inventors have been inducted, mostly constituting historic persons from the past three centuries, but also including living inductees. Nominees must hold a US patent of significant contribution to the US welfare, and which advances science and useful arts. History The National Inventors Hall of Fame was founded in 1973 on the initiative of H. Hume Mathews, then the chairman of the National Council of Patent Law Associations (now the National Council of Intellectual Property Law Associations). It was launched by Ed Sobey, who was also the first director. In 1974, it gained a major sponsor in the U.S. Patent and Trademar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ohio
Ohio ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the west, and Michigan to the northwest. Of the 50 List of states and territories of the United States, U.S. states, it is the List of U.S. states and territories by area, 34th-largest by area. With a population of nearly 11.9 million, Ohio is the List of U.S. states and territories by population, seventh-most populous and List of U.S. states and territories by population density, tenth-most densely populated state. Its List of capitals in the United States, capital and List of cities in Ohio, most populous city is Columbus, Ohio, Columbus, with the two other major Metropolitan statistical area, metropolitan centers being Cleveland and Cincinnati, alongside Dayton, Ohio, Dayton, Akron, Ohio, Akron, and Toledo, Ohio, Toledo. Ohio is nicknamed th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbus, Ohio
Columbus (, ) is the List of capitals in the United States, capital and List of cities in Ohio, most populous city of the U.S. state of Ohio. With a 2020 United States census, 2020 census population of 905,748, it is the List of United States cities by population, 14th-most populous city in the U.S., the second-most populous city in the Midwestern United States, Midwest (after Chicago), and the third-most populous U.S. state capital (after Phoenix, Arizona, and Austin, Texas). Columbus is the county seat of Franklin County, Ohio, Franklin County; it also extends into Delaware County, Ohio, Delaware and Fairfield County, Ohio, Fairfield counties. The Columbus metropolitan area, Ohio, Columbus metropolitan area encompasses ten counties in central Ohio and had a population of 2.14 million in 2020, making it the Ohio statistical areas, largest metropolitan area entirely in Ohio and Metropolitan statistical area, 32nd-largest metro area in the U.S. Columbus originated as several Nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tire
A tire (North American English) or tyre (Commonwealth English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineering), traction on the surface over which the wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, providing a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch, designed to match the vehicle's weight and the bearing on the surface that it rolls over by exerting a pressure that will avoid deforming the surface. The materials of modern pneumatic tires are synthetic rubber, natural rubber, fabric, and wire, along with carbon black and other chemical compounds. They consist of a tire tread, tread and a body. The tread provides Traction (engineering), traction while the body provides containment for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pennsylvania
Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions of the United States. It borders Delaware to its southeast, Maryland to its south, West Virginia to its southwest, Ohio and the Ohio River to its west, Lake Erie and New York (state), New York to its north, the Delaware River and New Jersey to its east, and the Provinces and territories of Canada, Canadian province of Ontario to its northwest via Lake Erie. Pennsylvania's most populous city is Philadelphia. Pennsylvania was founded in 1681 through a royal land grant to William Penn, the son of William Penn (Royal Navy officer), the state's namesake. Before that, between 1638 and 1655, a southeast portion of the state was part of New Sweden, a Swedish Empire, Swedish colony. Established as a haven for religious and political tolerance, the B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suicide
Suicide is the act of intentionally causing one's own death. Risk factors for suicide include mental disorders, physical disorders, and substance abuse. Some suicides are impulsive acts driven by stress (such as from financial or academic difficulties), relationship problems (such as breakups or divorces), or harassment and bullying. Those who have previously attempted suicide are at a higher risk for future attempts. Effective suicide prevention efforts include limiting access to methods of suicide such as firearms, drugs, and poisons; treating mental disorders and substance abuse; careful media reporting about suicide; improving economic conditions; and dialectical behaviour therapy (DBT). Although crisis hotlines, like 988 in North America and 13 11 14 in Australia, are common resources, their effectiveness has not been well studied. Suicide is the 10th leading cause of death worldwide, accounting for approximately 1.5% of total deaths. In a given year, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
