The activation energy of a chemical reaction is the minimum energy that is needed to make the reaction happen. It usually has the symbol E and it is measured in kilojoule per mole. It can be thought of as a barrier between the reagents and the products of a reaction. The activation energy is the difference in energy between the transition state and the starting reagents.
This equation is a way of calculating the activation energy. Its form is:
Here, "k" is the rate constant of the reaction (which can be measured using chemical kinetics), "A" is a frequency factor, "R" is the universal gas constant, "T" is the temperature. If we measure how fast the reaction goes at different temperatures, then we can make a graph and calculate the activation energy using this equation.
When using a catalyst the activation energy is made smaller. This means that the reaction can go faster at the same temperature. The catalyst does not change the energy of the reagents or the products. Also, the catalyst does not change in the reaction. Therefore, it can be used again and again and only a small amount of a catalyst is needed.
300 (graphic novel)
300 is a graphic novel written and drawn by Frank Miller and colored by Lynn Varley. It tells the story of the Spartans, the Persians, and the Battle of Thermopylae. The individual volumes were collected and reprinted in their entire by Dark Horse in 1999. "Publishers Weekly" wrote: "Form and content are ideally wedded: Miller's writing is stark, his drawings moody and dramatic, and intensified by Varley's grimly appropriate palette of earth and blood. The reader can see and feel the harshness of both the Grecian landscape and Sparta's battle-worshipping culture, as Miller presents the complex historical moment facing the 300." The novel was made into a movie.
Sacred Band of Thebes
The Sacred Band of Thebes was an elite fighting unit within the ancient Theban army of the 4th century BC. The earliest surviving record of the Sacred Band by name was made in 324 BC. The unit was comprised of 150 male lovers. It was believed these men would make better warriors. Plutarch (46–120 AD) is the source of the most substantial surviving account of the Sacred Band. In his "Life of Pelopidas" Plutarch wrote, "Since the lovers, ashamed to be base in sight of their beloved, and the beloved before their lovers, willingly rush into danger for the relief of one another." The band was reportedly organized by the Theban commander Gorgidas in 378 BC. Male couples were originally dispersed throughout the ranks of the army. It was later decided to create a separate squad. The squad played a crucial role in the Battle of Leuctra. It was completely destroyed by Philip II of Macedon in the Battle of Chaeronea in 338 BC.
Jerry Hopkins
Elisha Gerald "Jerry" Hopkins (November 9, 1935 – June 3, 2018) was an American journalist and author. He was best known for writing the first biographies of both Elvis Presley and Jim Morrison of The Doors, as well as serving for 20 years as a writer for "Rolling Stone" magazine. He also wrote several other biographies, wrote history and humor, and was a writer-producer for Mike Wallace, Steve Allen and Mort Sahl. He has published 36 books and an estimated one thousand magazine articles. The books have been translated into 16 languages and total sales exceed 6 million.
Hopkins was born on November 9, 1935 in Camden, New Jersey. He was raised in nearby Haddonfield, a town founded by Quakers. His parents operated a dry cleaning store.
He attended a Quaker school through 6th grade and public schools through 12th. He earned a BA in journalism from Washington & Lee University in Lexington, Virginia (1957). For a short time, he worked as a reporter for the "Twin City Sentinel" in Winston-Salem, North Carolina. He was in the US Army for a short time. After that, he earned an MS in journalism from Columbia University in New York (1959).
After freelancing articles to the then-young "Village Voice" while at Columbia, he worked as a reporter for the "Times-Picayune" and as news editor of WWL Radio in New Orleans (1959-1961). He joined Mike Wallace as a writer-producer in New York for one year (1961-62) then moved to Los Angeles where he was a talent coordinator and writer-producer for Steve Allen (1962-1964). He also wrote and produced television programs for Mort Sahl, ABC-TV and Universal Studios (1964-1966; 1971). He wrote his first books during this period, an as-told-to autobiography of a health faddist, "Bare Feet and Good Things to Eat" (1965), and an astrological spoof, "You Were Born on a Rotten Day" (1969).
In the mid-1960s, he left television to open the first “headshop” in Los Angeles. He then became the Los Angeles correspondent for "Rolling Stone" (1967-1969). He wrote features and columns for alternative newspapers, MC’ed the first love-ins in Los Angeles, edited a collection of material from the underground press, "The Hippie Papers" (1968) and wrote a history of rock and roll, "The Rock Story" (1970).
Leaving "Rolling Stone" temporarily in 1969 to write "Elvis: A Biography" (1971), it was while then serving as the magazine’s London correspondent (1972) he began researching his Morrison biography, "No One Here Gets Out Alive". It was rejected by more than 30 publishers before publication in 1980, when it topped the "New York Times" bestseller chart and was credited by many with helping kick-start the Doors’ revival as well as inspiring a new publishing genre, the rock biography. A sequel to the Elvis biography, "Elvis: The Final Years" (1981) followed, along with biographies of Jimi Hendrix, David Bowie, Yoko Ono, and Raquel Welch, the latter of which was authorized but not published.
He moved to Honolulu, where he edited a monthly newsletter about Hawaiian music and dance and published several books taking Hawaiian culture as their subject, including "The Hula" (1981), a history; "How to Make Your Own Hawaiian Musical Instruments" (1988); "Elvis in Hawaii" (2002); and "Don Ho: My Life, My Music" (2007). He also was an editor at Pacific Business News in Honolulu and a speechwriter for Mayor Frank Fasi.
Moving to Thailand in 1993, he wrote for many travel, food and airline magazines. He worked with photographer Michael Freeman on "Strange Foods: An Epicurean Adventure Around the World" (1999), which was expanded and reissued as "Extreme Cuisine" with a foreword by Anthony Bourdain (2004). A collection of expatriate profiles, "Bangkok Babylon" (2005); a book of stories and essays, "Thailand Confidential" (2005); and "Asian Aphrodisiacs" (2006) followed. His 37th book, profiling Western novelists who helped forge the Asian myth, "Romancing the East", will be published in 2013.
Hopkins has been married four times, to Sara Cordell (1959-1963), Jane Hollingsworth (1968-1976), Rebecca Erickson Crockett (1980-1988) and has two grown children by his second wife, Erin Hendershot (b.1970) and Nick Hopkins (b. 1972), and six grandchildren. He and his wife, Lamyai (m. 2003), a citizen of Thailand, divide their time between a flat in Bangkok and a house and farm six hours away in rice country near the Cambodian border.
Hopkins died on June 3, 2018 in Bangkok of heart failure at the age of 82.
Themistocles
Themistocles (?524 BC-?460 BC) was an Ancient Greek Athenian politician and general. He fought against the Persians at the Battle of Marathon as a young man. He later persuaded Athens to build a navy which he commanded in the defeat of the Persians at the Battle of Salamis in 480 BC.
After the war he became unpopular and had to leave. He went to work for the Persian Empire.
Greek shield
The "Greek shield" of Ancient Greece was called a hoplon or aspis. It was from this word that hoplite (a Greek soldier) is derived.