Semiconductors are most often made from silicon. Silicon is an element with four electrons in its outer shell. To make a p-type semiconductor extra materials like boron or aluminium are added to the silicon. These materials have only three electrons in their outer shell. When the extra material replaces some of the silicon it leaves a 'hole' where the fourth electron would have been if the semiconductor was pure silicon.
P-type semiconductors are made by doping the pure semiconductor material. The amount of impurity added is very small compared to the amount of semiconductor. The exact character of the semiconductor can be changed by varying the amount of 'dopant' that is added. In p-type semiconductors the number of holes is much higher than that of thermally generated electrons.
Boron doped Silicon, Aluminum doped Silicon, Boron doped Germanium etc. are the examples of p-type semiconductors.
Finger Plan
The Finger Plan () is an urban plan from 1947 which provides a strategy for the development of the Copenhagen metropolitan area in Denmark. According to the plan, all future development of Copenhagen would be along five 'fingers'. These grouped business areas would be near S-train commuter rail lines. The finger-line areas extend from the 'palm' which represents the dense urban area of central Copenhagen. Between the 'fingers', is land for agriculture and recreational use.
By the definition used in the Finger Plan, the metropolitan area has a population of 1,930,260 (1 October 2011). It has an area of over 34 municipalities.
In 2007 the Finger Plan was updated to the "Finger Plan 2007". This plan is written into the laws and is legally binding over Greater Copenhagen. The Finger Plan for 2007 does share the metropolitan area like this:
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Mullumbimby, New South Wales
Mullumbimby is a town in New South Wales, Australia. It is sometimes called "The Biggest Little Town in Australia".
High Rock Lake
High Rock Lake is a reservoir lake located in Davidson and Rowan counties of North Carolina. It serves as a border between them. It is a reservoir for hydroelectric power generation. It is the northernmost of the Uwharrie Lakes. High Rock is the second largest lake in North Carolina after Lake Norman. Its water surface covers and there are of shoreline. High Rock Lake begins at the confluence of the Yadkin River and the South Yadkin River. The lake's name comes from nearby "High Rock Mountain", the tallest mountain in the Uwharrie Mountains. High Rock Lake is currently managed and operated by the Alcoa company.
Pee Dee River
The Pee Dee River, also called the Great Pee Dee River, is a river in North Carolina and South Carolina. It originates in the Appalachian Mountains in North Carolina. Its upper course, above the mouth of the Uwharrie River, is known as the Yadkin River. It has a number of dams for flood control and hydroelectric power. The lower part of the river is named Pee Dee (in colonial times written Pedee). It is named after the Native American Pee Dee people. The Pee Dee region of South Carolina was named after either the tribe or the river. The first Europeans believed to have navigated part of the river was a party sent by Lucas Vázquez de Ayllón in 1521. They named it "River of St. John the Baptist ()."
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Savannah River
The Savannah River is a major river in the southeastern United States. It makes up most of the border between the states of South Carolina and Georgia. The Savannah River drainage basin extends into the southeastern side of the Appalachian Mountains just inside North Carolina. It is bounded by the Eastern Continental Divide. It is formed by the confluence of the Tugaloo River and the Seneca River. Today this confluence is under Lake Hartwell, a man-made reservoir. From Lake Hartwell to the Atlantic Ocean the Savannah River is long.
Two major cities are located along the Savannah River: Savannah, and Augusta, Georgia. They were the center of early English settlements during the Colonial period of American history. The Savannah River is tidal at Savannah. Downstream from there, the river widens into an estuary. Then it flows into the Atlantic Ocean. The area where the river's estuary meets the ocean is known as "Tybee Roads". The Intracoastal Waterway flows through a section of the Savannah River near the city of Savannah.
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Dan Fredinburg
Daniel Paul Fredinburg (September 8, 1981 – April 25, 2015) was an American engineer and Google executive. He was a product manager and head of privacy at Google X. He was born in Mission Viejo, California. From January 2013 to February 2014, he dated actress Sophia Bush.
Fredinburg died on Mount Everest in an avalanche caused by the April 2015 Nepal earthquake. He was 33.
Sid Tepper
Sid Tepper (June 25, 1918 – April 24, 2015) was an American songwriter. He was best known for working with with Roy C. Bennett, which created several hits for Elvis Presley. Between 1945 and 1970, Tepper and Bennett published over 300 songs.
He died on April 24, 2015, at the age of 96.
George C. Young
George Cressler Young (né Jung; August 4, 1916 – April 24, 2015) was an American lawyer and judge. He was a United States District Judge of the United States District Court for the Middle District of Florida. Young was born in Cincinnati, Ohio.
Young was reassigned to the United States District Court for the Middle District of Florida on October 29, 1962. He served as chief judge from 1973 to 1981 and assumed senior status on October 19, 1981.
Young died of a heart attack in Orlando, Florida, aged 98.
Sabeen Mahmud
Sabeen Mahmud () was a Pakistani human rights activist and social NGO worker. She was the founder and director of the Karachi-based cafe The Second Floor (T2F) and president of the Karachi branch of TiE.
On 24 April 2015, she was shot dead by unidentified gunmen in Karachi while on her way home after attending a seminar.
Rustum Ghazaleh
Rustum Ghazaleh () also transl. from Arabic as Rostom Ghazale, Rustom Ghazalah, Rustom Ghazali; 3 May 1953 – 24 April 2015) was a Syrian military and intelligence officer. On 24 July 2012, Ghazaleh was appointed chief of political security.
Ismail Hussain
Ismail Hussain (1 April 1950 – 24 April 2015) was an Indian politician. He was a member of the Indian Parliament representing the Barpeta (Lok Sabha constituency) for the Indian National Congress party.
Jim Fanning
William James Fanning (September 14, 1927 – April 25, 2015) was an American catcher, manager and front office executive in Major League Baseball. He was born in Chicago, Illinois.
He was the first general manager of the Montreal Expos of the National League (appointed in August 1968), he served the Expos in a number of capacities for almost 25 years. He served as their field manager in 1981. He guided Montreal into the playoffs for the only time in the 36-year history of the franchise.
Fanning died on April 25, 2015, at his home in London, Ontario, aged 87.
Anton Vratuša
Anton Vratuša, born Vratussa Antal (21 February 1915 – 30 July 2017) was a former politician and diplomat. He was Prime Minister of Slovenia and Yugoslavia's ambassador to the United Nations. Vratuša died on 30 July 2017 at the age of 102.
Alfonso Oiterong
Alfonso Rebochong Oiterong (October 9, 1924 – August 30, 1994) was a politician from Palau. He was the country's Vice-President from 1981 to 1985. He was President from 2 July to 25 October 1985.
Ken Birch
Kenneth Joseph "Ken" Birch (31 December 1933 – 24 April 2015) was an English footballer. He played as a right-half for Everton and Southampton. Later, he led Welsh club Bangor City to victory in the Welsh Cup in 1962. He played from the 1951 until after 1963.
Birch was born in Birkenhead, Cheshire. He died on 24 April 2015, aged 81.
Wang Guozhen