text:
Talk:Lake County, Oregon

Content suggestions
I've upgraded somewhat, to the WikiProject U.S. counties standards. More work is needed. Here's a clip from the Project page for guidance and general to do list:

 * Introduction
 * History
 * Origin of the county's name
 * Circumstances of the county's establishment
 * Major historical events that occurred in county
 * Law/Government
 * County Executive-- current, previous executives
 * representative body?
 * Geography
 * County seat -- see complete list of county seats at http://www.campbellslist.com/county_seats/select_county_seat.php
 * Physical geography (area, unique features)
 * Geographic center and bounds, polygonal outline (latitude and longitude points)
 * List of Townships or other subdivisions
 * List of Municipalities
 * List of contiguous counties
 * Major Parks and Cultural Institutions
 * Notable Festivals and Parades, with dates
 * Economy
 * Major industries/products
 * Taxes
 * Demographics
 * County population
 * Racial/ethnic makeup
 * Religious makeup
 * List of Census-recognized cities and towns in the county
 * List of unincorporated communities in the county
 * List of adjacent counties
 * County Name - direction to border/optional direction to county
 * Note border shared with other country, if exists
 * Link back to full list of counties for state
 * Start at northernmost point, and move clockwise
 * See Jefferson County, Washington for example
 * Colleges/Universities in county, sporting teams in county, similar lists
 * A link to a list of counties in that county's state

I will continue to hammer at it and welcome some help, since I'm new to Lake County. Duff 07:55, 28 May 2007 (UTC)

 * One might also mention some of the more notorious aspects of Lake County's sociology. It is historically one of Oregon's poorer counties with a rather high incidence of unemployment, chronic underemployment, and people on public assistance, leading to all the afflictions of poverty:  drug use, alcoholism, youth disaffection, and a reaction by the authorities to use the police forces as agents of social change.Uniquerman (talk) 20:49, 4 January 2012 (UTC)

 * Moreover, Lake County is listed among the top five or six counties in total crime rate in the state. It  has one of the highest rates of aggravated assault of any jurisdiction in the United States, recently 20 or so per annum in a population less than 8000, although the sample may be too small for large conclusions.  The burglary rate is roughly equivalent to the tenth worst city in the country.  It is higher than Portland, twice as high as L. A., and 4.5 times worse than New York.  An encyclopedia ought to be encyclopedic, not a marketing tool. Euonyman (talk) 15:25, 17 August 2012 (UTC)

 * Hey thanks for working to improve one of the sadly neglected county articles. Just a note about my pet area--since Oregon doesn't have any "towns" (see the explanation at Category:Towns in Oregon and Category:Towns in the United States), I think the previous heading "Communities" is more accurate, and it's consistent with the rest of the Oregon county articles. The WikiProject guidelines are excellent, but I think it's OK to customize them a bit. P.S. Let me know if you want me to look up anything in Oregon Geographic Names. Katr67 13:58, 28 May 2007 (UTC)

 * It's pretty clear where the name of the county came from — Goose Lake, Summer Lake, Silver Lake, the Warner Lakes — as well as the name of the county seat — Lakeview. At the time the town was settled, in the 1870s, Goose Lake was at one of its periodic high points, in a cycle common for those playas at the foot of the block fault mountains in the Basin and Range country of the interior West. The block fault mountain in the case of Goose Lake would be Sugarloaf, on the east side of the lake, south of Willow Ranch, California. At that time, the lake came up to what is now the western edge of the town of Lakeview. A steamboat ran from the southern end of the lake at the head of the Pit River to the town of Lakeview, because the mountains on either edge of the lake presented pretty formidable obstacles to road-building, and a boat run was considerably easier. The lake has receded considerably from that high point, although not back to the lows of the 1840s, when the Applegate party came over the Fandango Pass out of Surprise Valley in their wagons, and crossed the bed of the lake, which was completely dry at that time. Some say that in some places you can still see the wagon tracks. MaxwellPerkins (talk) 07:46, 8 January 2010 (UTC)

New material
The recent expansion of the article is great, but be sure to cite any new info. Read about citations and reliable sources for more information. Please make sure none of this is original research, even if it's "common knowledge". Katr67 (talk) 16:40, 27 October 2008 (UTC)

Recent Additions
I see you noticed I added some stuff. Glad you like it. There are some broken links because Wikipedia doesn't have pages for the Lake County Museum, Warner Wetlands, and the Summer Lake Wildlife Area. But I left them in because I think they should/ will have articles. It's a nightmare trying to figure out how to spell everything just right so it links to the appropriate Wikipedia page.

Lake County is a great frontier area with amazing geology and history. So hopefully peeps will continue to add to this article. I added some external links so that should provide a good start anyway. PEACE!

This seems to be the best site for basic information and summaries to flesh out this article: http://www.lakecountychamber.org/facts/index.html.(JoeTimko (talk) 19:14, 27 October 2008 (UTC))

 * Clearly this article suffers from over-reliance on sanitized opinions of the Chamber of Commerce. "Cattle ranchers later feuded and discouraged the wandering sheepherders." Discouraged? That seems like a pretty mild term for the range wars between cattlemen and sheepmen. Cattlemen armed with rifles killed sheep in the northern part of the county in the early 1900s, in disputes over grazing rights, exacerbated by the introduction of wheat farming. According to the Oregon History Project, 2,300 sheep were killed in a single night in April 1904 in Lake County. (http://www.ohs.org/education/oregonhistory/historical_records/dspDocument.cfm?doc_ID=8A032B61-99BB-85F8-059105E03E7F13D6) MaxwellPerkins (talk) 03:14, 24 April 2010 (UTC)

 * Somehow the original link that I inserted to a page on the Oregon History Project web site got changed to a link to a (non-existent) Wikipedia page. I changed it back. MaxwellPerkins (talk) 20:15, 4 November 2013 (UTC)

 * After having my change reverted by EncMstr, and being chastised for making it and having a faulty memory to boot, I removed the link around "Oregon History Project," because that link to a non-existent Wikipedia page must have made it seem to the casual reader as if the source material didn't exist. Whereas now the casual reader will have to dig down into the references, which may not be obvious, as opposed to using a straightforward link, as almost all other web pages do. MaxwellPerkins (talk) 20:44, 4 November 2013 (UTC)

Poor Lake County
I see that, according to Wikipedia, Lake County is not in Eastern Oregon, Central Oregon or Southern Oregon. I'm flummoxed. When I was growing up there, we always thought we were in Eastern Oregon. Just goes to show how ephemeral childhood illusions can be. The hard-hearted world rejected them. I guess we can hark back to football of the early 90s, to the Lonesome End for a designation: Lonesome Oregon. MaxwellPerkins (talk) 06:52, 8 January 2010 (UTC)
 * Thank you for your suggestion. When you believe an article needs improvement, please feel free to make those changes. Wikipedia is a wiki, so anyone can edit almost any article by simply following the  link at the top. The Wikipedia community encourages you to be bold in updating pages. Don't worry too much about making honest mistakes—they're likely to be found and corrected quickly. If you're not sure how editing works, check out how to edit a page, or use the sandbox to try out your editing skills.  New contributors are always welcome. You don't even need to log in (although there are many reasons why you might want to). Katr67 (talk) 07:05, 8 January 2010 (UTC)
 * Not a suggestion, but a lament. MaxwellPerkins (talk) 07:47, 8 January 2010 (UTC)

Oregon's outback.
One might beware of calling Lake County Oregon's Outback. No one who comes from there knows exactly where that is, except that the Federal Highway Administration has designated the route from LaPine along Hwy. 37 connecting to Hwy. 395 and south to Lakeview the Oregon Outback Scenic Byway. Oregon Outback was a term encouraged by ambitious local boosters to give the wild and rugged desolation of the area the magic of an undiscovered tourist destination and to develop an interest in its untrammeled remoteness. Before 1990 or so, very few people had heard of the phrase. Somehow the catchiness of it stuck and, like the expression Goose Lake Valley instead of Goose Valley, it is taken as having some historic value when it is a neologism.

Nothing wrong with new words, but if Oregon does have an outback, I'm sure it extends to all that part of the Great Basin west of the Snake River watershed.Uniquerman (talk) 20:39, 4 January 2012 (UTC)

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 * Added archive https://web.archive.org/web/20131002153656/http://www.bendbulletin.com/apps/pbcs.dll/article?AID=%2F20090816%2FNEWS0107%2F908160416%2F1001%2FNEWS01&nav_category=NEWS01 to http://www.bendbulletin.com/apps/pbcs.dll/article?AID=%2F20090816%2FNEWS0107%2F908160416%2F1001%2FNEWS01&nav_category=NEWS01
 * Added archive https://archive.is/20160708144914/http://www.census.gov/popest/data/counties/totals/2015/CO-EST2015-alldata.html to http://www.census.gov/popest/data/counties/totals/2015/CO-EST2015-alldata.html

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 * Added tag to http://www.heraldandnews.com/articles/2008/10/12/news/diversions/doc48d2fbf09b840436604006.txt
 * Added archive https://web.archive.org/web/20110201110257/http://lakecountymuseum.com/ to http://lakecountymuseum.com/
 * Added archive https://web.archive.org/web/20151130034008/https://fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5418811.pdf to https://fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5418811.pdf
 * Added archive https://web.archive.org/web/20101221020851/http://www.oregon.gov/DOC/OPS/PRISON/wccf.shtml to http://www.oregon.gov/DOC/OPS/PRISON/wccf.shtml
 * Added archive https://web.archive.org/web/20110217021541/http://oregonmag.com/LakeCoTrav304.htm to http://oregonmag.com/LakeCoTrav304.htm
 * Added archive https://web.archive.org/web/20101221020851/http://www.oregon.gov/DOC/OPS/PRISON/wccf.shtml to http://www.oregon.gov/DOC/OPS/PRISON/wccf.shtml
 * Added archive https://web.archive.org/web/20090327184823/http://egov.oregon.gov/OSP/NEWSRL/news/09_07_2008_wccf_escape.shtml to http://egov.oregon.gov/OSP/NEWSRL/news/09_07_2008_wccf_escape.shtml
 * Added archive https://web.archive.org/web/20110201110257/http://lakecountymuseum.com/ to http://www.lakecountymuseum.com/
 * Added archive https://web.archive.org/web/20061208132931/http://www.irishsheepherders.com/ to http://www.irishsheepherders.com/

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 * Added archive https://web.archive.org/web/20110716112903/http://www.southernoregon.com/lakes/bluejointlake/index.html to http://www.southernoregon.com/lakes/bluejointlake/index.html

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title: Talk:Lake County, Oregon


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Talk:Lane County, Oregon

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Lane as pro-slavery in intro
I'm wondering about the mention of Lane's pro-slavery stance in the intro. It was added by an anon a long time ago: diff. Of course as a schoolkid growing up in Lane County, nobody ever told me the political ideals of Lane, but I'm not sure that's the most relevent thing to mention about him in the intro unless it's in turn relevent to the naming of the county? Of course such a fact should not be *ahem* whitewashed, but on the other hand, I'm wondering if the addition of this fact is being used to to try to prove some point? Thoughts? Katr67 21:25, 14 June 2007 (UTC)

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 * Added archive https://web.archive.org/web/20081016104412/http://www.co.lane.or.us/About/default.htm to http://www.co.lane.or.us/About/default.htm
 * Added archive https://archive.is/20130201044428/http://www.registerguard.com/web/newslocalnews/25926310-41/population-growth-county-oregon-lane.html.csp to http://www.registerguard.com/web/newslocalnews/25926310-41/population-growth-county-oregon-lane.html.csp
 * Added archive https://web.archive.org/web/20121008004013/http://www.oregon.gov/CJC/docs/LaneCountyCriminalJusticeReportSec.pdf to http://www.oregon.gov/CJC/docs/LaneCountyCriminalJusticeReportSec.pdf

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Merge the Globe Article to This Article
I suggest that all information about Globe, Oregon be merged into the Communities section of this article. Anonymy365248 (talk) 17:03, 10 June 2024 (UTC)
 * The Globe, Oregon doesn't, or no longer, exists. Klbrain (talk) 08:19, 7 July 2024 (UTC)
 * Was it merged to this article or was it deleted? Anonymy365248 (talk) 06:29, 10 July 2024 (UTC)

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Talk:Lincoln County, Oregon

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Talk:Linn County, Oregon

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Isabelle Adjani

Isabelle Yasmine Adjani (born 27 June 1955) is a French actress and singer of Algerian and German descent.

She is the only performer to win five César Awards for acting—all in the Best Actress category—for Possession (1981), One Deadly Summer (1983), Camille Claudel (1988), La Reine Margot (1994), and Skirt Day (2009). She was made a Knight of the Legion of Honour in 2010 and a Commander of the Order of Arts and Letters in 2014.

Her portrayal of Adèle Hugo in The Story of Adèle H. (1975) earned Adjani her first nomination for the Academy Award for Best Actress, which made her, at 20, the youngest nominee in that category at the time. Her second Best Actress nomination came in 1990 for portraying Camille Claudel, making her the first French actress to receive two Academy Award nominations for foreign-language films. She won the Cannes Film Festival Award for her performances in Possession and Quartet (1981), becoming the only actress to win a joint award for two films in the same competition slate, and a Berlin Silver Bear for Camille Claudel.

Her other notable film roles include The Slap (1974), The Tenant (1975), Barocco (1976), The Driver (1978), Nosferatu the Vampyre (1979), All Fired Up (1982), Subway (1985), Ishtar (1987), Diabolique (1996), Adolphe (2002), Bon voyage (2003), French Women (2014), The World Is Yours (2018) and Peter von Kant (2022).

Early life and education
Isabelle Yasmine Adjani was born on 27 June 1955 in the 17th arrondissement of Paris, to Mohammed  Cherif Adjani, an Algerian Muslim from Constantine, and Emma Augusta "Gusti" Schweinberger, a German Catholic from Bavaria.

Adjani's parents met near the end of World War II, when her father was in the French Army and stationed in Germany. They married and her mother returned with him to Paris, despite not speaking a word of French. She asked him to take Cherif as his first name as she thought it sounded more "American".

Isabelle grew up bilingual, speaking French and German fluently, in Gennevilliers, a northwestern suburb of Paris, where her father worked in a garage. After winning a school recitation contest, Adjani began acting by the age of 12 in amateur theater. She successfully passed her baccalauréat and was auditing classes at the University of Vincennes in 1976.

Adjani had a younger brother, Éric, who was a photographer. He died on 25 December 2010, aged 53.

Acting career

At the age of 14, Adjani starred in her first motion picture, Le Petit Bougnat (1970). She first gained fame as a classical actress at the Comédie-Française, which she joined in 1972. She was praised for her interpretation of Agnès, the main female role in Molière's L'École des femmes. She soon left the theatre to pursue a film career.

After minor roles in several films, she enjoyed modest success in the 1974 film La Gifle (The Slap), which François Truffaut saw. He immediately cast her in her first major role in his The Story of Adèle H. (1975) which he had finished writing five years prior. Critics praised her performance, with the American critic Pauline Kael describing her acting talents as "prodigious".

Only 19 when she made the film, Adjani was nominated for the Academy Award for Best Actress in a Leading Role, becoming the youngest Best Actress nominee at the time (a record she held for almost 30 years). She quickly received offers for roles in Hollywood films, such as Walter Hill's 1978 crime thriller The Driver. She had previously turned down the chance to star in films like The Other Side of Midnight. She had described Hollywood as a "city of fiction" and said, "I'm not an American. I didn't grow up with that will to win an award." Truffaut on the other hand said, "France is too small for her. I think Isabelle is made for American cinema." She agreed to make The Driver because she was an admirer of Hill's first film Hard Times. Adjani said: "I think he is wonderful, very much in the tradition of Howard Hawks, lean and spare. The story is contemporary but also very stylized, and the roles that Ryan and I play are like Bogart and Bacall. We are both gamblers in our souls and we do not show our emotions or say a lot. For us, talk is cheap. I am really quite a mysterious girl in this film, with no name and no background. And I must say that it is restful not to have a life behind me; this way, I don't have to dig deep to play the part. All I know is that life for me is gambling and I am a loser. I have what people call a poker face." The film was seen more than 1.1 million times in Adjani's native France but did not do as well in the US.

She played Lucy in the German director Werner Herzog's 1979 remake of Nosferatu which was well-received critically and performed well at box offices in Europe. Roger Ebert loved the film, calling Herzog's casting of Adjani one of his "masterstrokes" in the film. He wrote that she "is used here not only for her facial perfection but for her curious quality of seeming to exist on an ethereal plane." The cast and the crew filmed both English- and German-language versions simultaneously upon request of 20th Century Fox, the American distributor, as Kinski and Ganz could act more confidently in their native language.

In 1981, she received a double Cannes Film Festival's Best Actress award for her roles in the Merchant Ivory film Quartet, based on the novel by Jean Rhys, and in the horror film Possession (1981). The following year, she received her first César Award for Possession, in which she had portrayed a woman having a nervous breakdown.

In 1983, she won her second César for her depiction of a vengeful woman in the French blockbuster One Deadly Summer, and starred with Michel Serrault in the black diamond thriller Deadly Circuit directed by Claude Miller. That same year, Adjani released the French pop album Pull marine, written and produced by Serge Gainsbourg. She then starred in a music video for the hit title song, Pull Marine, which was directed by Luc Besson.

Adjani also drew controversy at the 1983 Cannes Film Festival when she refused to attend a traditional photocall after the press conference for One Deadly Summer. Adjani was annoyed at the time by the intrusion of photographers into her private life. The photographers in Cannes boycotted Adjani upon her arrival on the red carpet for the premiere, at which point they put down their cameras down and turned their backs to her.

In 1988, she co-produced and starred in a biopic of the sculptor Camille Claudel. She received her third César and second Oscar nomination for her role in the film, becoming the first French actress to receive two Oscar nominations. The film was also nominated for the Academy Award for Best Foreign Language Film.

She received her fourth César for the 1994 film Queen Margot, an ensemble epic directed by Patrice Chéreau. She received her fifth César for Skirt Day (2009), the most that any actress has received. The film features her as a middle school teacher in a troubled French suburb who takes her class hostage when she accidentally fires off a gun she found on one of her students. It was premiered on the French Arte channel on 20 March 2009, attaining a record 2.2 million viewers) and then in movie theaters on 25 March 2009. The film was her return to the cinema after eight years of absence.

In 2010, she made an appearance in the social comedy Mammuth, from directors Benoît Delépine and Gustave Kervern, and in which she played the phantom of Gérard Depardieu's first love. The same year, she lent her voice to the character of Mother Gothel in the french version of the animated film Tangled. In 2011, she co-starred in De Force, the first film directed by Frank Henry. She embodied the commander Clara Damico, head of the brigade for the repression of banditry.

She became the first French actress to star in a Bollywood film, playing the mother of Preity Zinta in the 2013 romantic comedy Ishkq in Paris, directed by Prem Soni and alongside Shekhar Kapur.

She joined the comedy The World Is Yours, playing the eccentric Dany, directed by Romain Gavras alongside Vincent Cassel, which entered into the Directors' Fortnight during the 2018 Cannes Film Festival.

In 2022, she played the movie star Sidonie von Grassenabb in the comedy drama Peter von Kant, tribute to Rainer Werner Fassbinder's The Bitter Tears of Petra von Kant, directed by François Ozon alongside Denis Ménochet, which entered as the opening film into the 72nd Berlin International Film Festival.

In 2023, Adjani released her second French pop album Bande originale, written and produced by Pascal Obispo, and arranged by Cécile DeLaurentis. She also joined the Netflix action film Wingwomen, directed by Mélanie Laurent, and then, the Netflix miniseries The Perfect Couple directed by Susanne Bier, alongside Nicole Kidman and Liev Schreiber.

Personal life
In 1979, Adjani had a son, Barnabé Saïd-Nuytten, with the cinematographer Bruno Nuytten, whom she later hired to direct her project Camille Claudel, a biopic of the sculptor who was the lover of Rodin.

During the mid-eighties, she had a relationship with Warren Beatty, who convinced her to appear with him in the epic comedy Ishtar, directed by Elaine May, co-starred by Dustin Hoffman, and shot in Morocco.

From 1989 to 1995, she had a relationship with Daniel Day-Lewis, which ended before the birth of their son, Gabriel-Kane Day-Lewis, in 1995.

Adjani was later engaged to the composer Jean-Michel Jarre; they broke up in 2004.

On 14 December 2023, Adjani was handed a  two-year suspended sentence for tax fraud.

Political views
Adjani has been vocal against anti-immigrant and anti-Algerian sentiments in France. In 2009, she criticized statements by Pope Benedict XVI, who claimed that condoms are not an effective method of AIDS prevention.

In September 2009, she signed a petition in support of Roman Polanski, calling for his release after he was arrested in Switzerland in relation to his sexual abuse case.

In 2017, Adjani was interviewed by Vincent Josse on the French public radio station France Inter. During the interview, she expressed her vaccine hesitancy and opposition to mandatory vaccination.

In 2018 Adjani signed a letter calling to act "firmly and immediately" for stopping climate change and biodiversity loss.

Honors
In addition to specific awards for particular films, Adjani was made a Knight of France's Legion of Honour on 14 July 2010 for her contributions to the arts.

Discography

 * 1983: Pull Marine (Mercury/Universal)
 * 2023: Adjani, Bande Originale (Warner Music International)

title: Isabelle Adjani


text: User:Michael Schulze

title: User:Michael Schulze


text:
Talk:Gas Laws

Merger proposal
I propose that Gas laws be merged into Gas. I think that the content in the Gas laws article can easily be explained in the context of Gas, and the Gas article is of a reasonable size in which the merging of Foo will not cause any problems as far as article size or undue weight is concerned. Katanada (talk) 07:33, 27 March 2011 (UTC)

(just testing an alternative presentation)

Usually expressed as:

 * PV = nRT

in full:

 * pressure × volume = amount of the material × temperature × constant

in SI units:

 * pascals × litres = moles × Kelvin × constant

-

should this page & others similar be merged & redirected to Equations of state?

I would say Yes for this page. I'm not sure which others you mean. I would not merge the Equations of state/History page into this page. -- Matt Stoker

-

If you really want to use SI units, volume should be in cubic meters. --Matt Stoker

title: Talk:Gas Laws


text:
User talk:Michael Schulze

Hello there Michael, welcome to the 'pedia! I hope you like the place and decide to stay. If you ever need editing help visit How does one edit a page and experiment at Sandbox. If you need pointers on how we title pages visit Naming conventions or how to format them visit our manual of style. If you have any other questions about the project then check out Help or add a question to the Village pump. BTW, thanks for the corrections to the video game articles. Cheers! --maveric149

title: User talk:Michael Schulze


text: User:Azerty~enwiki

title: User:Azerty~enwiki


text:
User talk:Azerty~enwiki

Hello there Azerty, welcome to the 'pedia! I hope you like the place and decide to stay. If you ever need editing help visit How does one edit a page and experiment at Sandbox. If you need pointers on how we title pages visit Naming conventions or how to format them visit our manual of style. If you have any other questions about the project then check out Help or add a question to the Village pump. Cheers! --maveric149

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Azerty. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Azerty~enwiki that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name. If you think you might own all of the accounts with this name and this message is in error, please visit Special:MergeAccount to check and attach all of your accounts to prevent them from being renamed.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 22:24, 19 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 10:49, 22 April 2015 (UTC)

title: User talk:Azerty~enwiki


text: User:Tim Marklew

title: User:Tim Marklew


text:
User talk:Tim Marklew

Hello there Tim, welcome to the 'pedia! I hope you like the place and decide to stay. If you ever need editing help visit How does one edit a page and experiment at Sandbox. If you need pointers on how we title pages visit Naming conventions or how to format them visit our manual of style. If you have any other questions about the project then check out Help or add a question to the Village pump. Cheers! --maveric149

title: User talk:Tim Marklew


text:
Patriarch Arsenius

Patriarch Arsenius may refer to:

 * Patriarch Arsenius of Alexandria, Greek Patriarch of Alexandria in 1000–1010
 * Patriarch Arsenius I of Constantinople, Ecumenical Patriarch of Constantinople in 1255–1260 and 1261–1267
 * Serbian Patriarch Arsenius II, Serbian Patriarch from 1457 to 1463
 * Serbian Patriarch Arsenius III, Serbian Patriarch from 1674 to 1690 (1706)
 * Serbian Patriarch Arsenius IV, Serbian Patriarch from 1725 to 1737 (1748)

title: Patriarch Arsenius


text: User:Agur Kesalat

title: User:Agur Kesalat


text:
Khan Yunis

Khan Yunis (خان يونس), also spelled Khan Younis or Khan Yunus, is a largely destroyed city in the southern Gaza Strip; it is the capital of the Khan Yunis Governorate in the Gaza Strip.

Before the 14th century, Khan Yunis was a village known as "Salqah". To protect caravans, pilgrims and travellers a vast caravan serai was constructed there by the emir Yūnus an-Nūrūzī in 1387–88, an official of the Mamluk Empire.

According to the Palestinian Central Bureau of Statistics, Khan Yunis had a population of 205,125 in 2017. Khan Yunis, which lies only 4 km east of the Mediterranean Sea, has a semi-arid climate with temperature of 30 °C maximum in summer and 10 °C minimum in winter, with an annual rainfall of approximately 260 mm.

Ancient period
Herodotus describes a city named Ienysos (Ιηνυσος) located between Lake Serbonis and Kadytis (modern Gaza city). He talks about how the Persian military marched through the location on its way to Egypt. He also describes how the coastal area between Kadytis and Ienysos was inhabited by local Arab tribes. Some sources, due to phonological resemblance of the names and due to the general matching of the geographic locations, associate this site with modern Khan Yunis.

Other sources have suggested a further inland location of "Khirbet Ma'in Abu Sitta" (Palestinian village depopulated in 1949, near modern kibbutz of Nir Oz) or the Egyptian town of Arish as possible locations of Ienysos, but there is no clear evidence to support this identification.

Ancient discoveries in Khan Yunis feature a lintel with a Greek inscription, discovered repurposed in the tomb of Sheikh Hamada. The inscription translates to: 'Hilarion - giving thanks to St. Georgius.' Originally housed in the Musée de Notre Dame de France in Jerusalem, the lintel is currently lost.

Establishment by Mamluks
Before the 14th century, Khan Yunis was a village known as "Salqah". To protect caravans, pilgrims and travellers a vast caravan serai was constructed there by emir Yūnus an-Nūrūzī in 1387–88, an official of the Mamluk Empire. The growing town surrounding it was named "Khan Yunis" after him. In 1389 Yunus was killed in battle. Yunus ibn Abdallah an-Nuruzi ad-Dawadar was the executive secretary (dawadar), one of the high-ranking officials of the Mamluk sultan Barquq. The town became an important center for trade and its weekly Thursday market drew traders from neighboring regions. ''

The khan served as resting stop for couriers of the barid, the Mamluk postal network in Palestine and Syria.

Ottoman period
In late 1516 Khan Yunis was the site of a minor battle in which the Egypt-based Mamluks were defeated by Ottoman forces under the leadership of Sinan Pasha. The Ottoman sultan Selim I then arrived in the area where he led the Ottoman army across the Sinai Peninsula to conquer Egypt. During the 17th and 18th centuries the Ottomans assigned an Asappes garrison associated with the Cairo Citadel to guard the fortress at Khan Yunis.

Pierre Jacotin named the village Kan Jounes on his map from 1799, while in 1838, Robinson noted Khan Yunas as a Muslim village located in the Gaza district. In 1863 French explorer Victor Guérin visited Khan Yunis. He found it had about a thousand inhabitants, and that many fruit trees, especially apricots were planted in the vicinity.

At the end of the 19th-century the Ottomans established a municipal council to administer the affairs of Khan Yunis, which had become the second largest town in the Gaza District after Gaza itself.

British Mandate
In the 1922 census of Palestine conducted by the British Mandate authorities, Khan Yunis had a population of 3890 inhabitants (3866 Muslims, 23 Christians, and one Jew), decreasing in the 1931 census to 3811 (3767 Muslims, 41 Christians, and three Jews), in 717 houses in the urban area and 3440 (3434 Muslims and 6 Christians) in 566 houses in the suburbs.

In the 1938 village statistics, the population is listed as 4,379 (including three Jews) with 3,953 in nearby suburbs. In the 1945 statistics, Khan Yunis had a population of 11,220 (11,180 Muslims and 40 Christians), with 2,302 (urban) and 53,820 (rural) dunams of land, according to an official land and population survey. Of this, 4,172 dunams were plantations and irrigable land, 23,656 used for cereals, while 1,847 dunams were built-up land.

During the Nazi occupation of the Dodecanese, many Greeks from Dodecanese islands such as Kastelorizo sought refuge in the nearby Nuseirat Camp.

1948–1967
During the night of 31 August 1955, three Israeli paratroop companies attacked the British-built Tegart fort in Khan Yunis from where attacks had been carried out against Israelis. The police station, a petrol station and several buildings in the village of Abasan were destroyed, as well as railway tracks and telegraph poles. In heavy fighting, 72 Egyptian soldiers were killed. One Israeli soldier was killed and 17 were wounded. The operation led to a ceasefire on September 4, forcing President Gamal Abdel Nasser and the Egyptian government to halt Palestinian fedayeen operations against Israel. One of the mechanized companies was commanded by Rafael Eitan.

Before the Suez War, Khan Yunis was officially administered by the All-Palestine Government, seated in Gaza and later in Cairo. After a fierce firefight, the Sherman tanks of the IDF 37th Armored Brigade broke through the heavily fortified lines outside of Khan Yunis held by the 86th Palestinian Brigade. It was the only site in the Gaza strip where the Egyptian army put up any resistance to the Israeli invasion of Gaza, but it surrendered on 3 November 1956.

There are conflicting reports of what happened. Israel said that Palestinians were killed when Israeli forces were still facing armed resistance, while the Palestinians said all resistance had ceased by then, and that many unarmed civilians were killed as the Israel troops went through the town and camp, seeking men in possession of arms.

The killings, dubbed the Khan Yunis massacre, were reported to the UN General Assembly on 15 December 1956 by the Director of the United Nations Relief and Works Agency, Henry Labouisse. According to the report, the exact number of dead and wounded is not known, but the director received lists of names of persons allegedly killed from a trustworthy source, including 275 people, of which 140 were refugees and 135 local residents.

After 1959, the All-Palestine Government of Gaza Strip was abolished and the city was included in the United Arab Republic, which was shortly disestablished and the Gaza Strip came under the direct Egyptian military occupation rule.

1967 and aftermath

In 1967, during the Six-Day War, Israel occupied Khan Yunis again.

Khan Yunis was the site of Israeli helicopter attacks in August 2001 and October 2002 that left several civilians killed, hundreds wounded and civilian buildings within the vicinity destroyed. It is known as a stronghold of the Palestinian Hamas.

It is currently an Area A territory in the state of Palestine.

Israel–Hamas war
During the ongoing Israel–Hamas war, Israel has bombed Khan Yunis along with other cities in the Gaza Strip as part of an offensive against Hamas. The Israeli Air Force extensively bombed much of the city, including the Hamad City apartment complex. Local sources have reported numerous civilian casualties in Khan Yunis as a result of Israeli bombings, which Palestinian news agency Wafa put at "at least 70" as of December 3. The Al Qarara Cultural Museum was destroyed in an explosion as a result of an Israeli attack in October 2023, part of an offensive that reportedly targeted civilian homes and mosques in the vicinity. Israeli armored units began entering the outskirts of the city in December 2023. After several months of fighting, Israeli forces ended up withdrawing from Khan Yunis and most of the southern Gaza Strip.

Economy
Khan Yunis is the second largest urban area in the Gaza Strip after Gaza City. It serves as the principal market center of the territory's southern half and hosts a weekly Bedouin souk ("open-air market") mostly involving local commodities. Khan Yunis had the highest unemployment rate in the Palestinian territories.

Education

 * University College of Science and Technology
 * Al Quds Open University

Notable people

 * Mohammed Shabir (1946 – 2023), former president of The Islamic University in Gaza
 * Yahya Sinwar (born 1962), a Palestinian politician who has been leader of Hamas, the Sunni Islamist political and military organization that rules the Gaza Strip, since 2017.

Twin towns – sister cities
Khan Yunis is twinned with the following cities:
 * 🇳🇴 Hamar, Norway
 * 🇪🇸 Almuñécar, Spain
 * 🇫🇷 Évry, France
 * 🇮🇹 Bisceglie, Italy
 * 🇮🇹 Alcamo, Italy

title: Khan Yunis


text:
User:Gbraad

To see my personal page, please go to:
 * Gerard Braad: personal website

title: User:Gbraad


text:
User talk:Gbraad

Wikinews demo up and running
Hi!

I'm writing to let you know that the Wikimedia Board of Trustees has approved the first stage of the Wikinews project. There's now a fully operational English demo site at demo.wikinews.org. This will be used for experimenting with various review models and basic policies before the site is launched officially in about a week. demo.wikinews.org will become the English version later. You voted for the Wikinews project, so I'm asking for your participation now. Everything is open, nothing is final. What Wikinews will and can be depends in large part on you. There already is a global Wikinews mailing list for discussing the project. If you are interested at all, please subscribe -- coordination is of key importance. There's also an IRC channel #wikinews on irc.freenode.net. Realtime discussion can help to polish up articles. If you're looking for something to do, check out the articles in development and articles in review. Or start a new story in the Wikinews workspace, or ignore the proposed review system - it's up to you. I hope you'll join us soon in this exciting experiment.--Eloquence* 01:58, Nov 17, 2004 (UTC)

Image:SMDTransistor.jpg
this image has no information on its source or copyright status.

please read and understand http://en.wikipedia.org/wiki/Wikipedia:Image_copyright_tags and tag the image apprpriately.

if you are not the creator of this image and the creator cannot be contacted or persuded to license it under terms acceptable to wikipedia the best resoloution would be for you to replace the image with one you take yourself. Plugwash 01:37, 23 Dec 2004 (UTC)

Image:Eric harris dylan klebold.jpg
Hi, which copyright license does this image have? Also, which source do you have? Thuresson 00:43, 31 Mar 2005 (UTC)

Non-free use disputed for Image:VirginLogo.PNG
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Disputed fair use rationale for Image:Eric harris dylan klebold.jpg
Thank you for uploading Image:Eric harris dylan klebold.jpg. However, there is a concern that the rationale provided for using this image under "fair use" may not meet the criteria required by Non-free content. This can be corrected by going to the image description page and add or clarify the reason why the image qualifies for fair use. Adding and completing one of the templates available from Fair use rationale guideline is an easy way to ensure that your image is in compliance with Wikipedia policy. Please be aware that a fair use rationale is not the same as an image copyright tag; descriptions for images used under the fair use policy require both a copyright tag and a fair use rationale.

If it is determined that the image does not qualify under fair use, it might be deleted by adminstrator within a few days in accordance with our criteria for speedy deletion. If you have any questions, please ask them at the media copyright questions page. Thank you. Ricky81682 (talk) 06:42, 7 March 2008 (UTC)

Proposed deletion of Amiga E

The article Amiga E has been proposed for deletion  because of the following concern:
 * No sign of notability

While all contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the article to address the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. The speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. Bulwersator (talk) 10:18, 11 July 2011 (UTC)

Possibly unfree File:Eric harris dylan klebold.jpg
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Proposed deletion of Dave Needle

The article Dave Needle has been proposed for deletion because it appears to have no references. Under Wikipedia policy, this biography of a living person will be deleted unless it has at least one reference to a reliable source that directly supports material in the article.

If you created the article, please don't be offended. Instead, consider improving the article. For help on inserting references, see Referencing for beginners, or ask at the help desk. Once you have provided at least one reliable source, you may remove the prod blp tag. Please do not remove the tag unless the article is sourced. If you cannot provide such a source within seven days, the article may be deleted, but you can when you are ready to add one. Q VVERTYVS (hm?) 07:01, 31 July 2015 (UTC)

title: User talk:Gbraad


text:
Euler–Jacobi pseudoprime

In number theory, an odd integer n is called an Euler–Jacobi probable prime (or, more commonly, an Euler probable prime) to base a, if a and n are coprime, and

 * $$a^{(n-1)/2} \equiv \left(\frac{a}{n}\right)\pmod{n}$$

where $$\left(\frac{a}{n}\right)$$ is the Jacobi symbol.

If n is an odd composite integer that satisfies the above congruence, then n is called an Euler–Jacobi pseudoprime (or, more commonly, an Euler pseudoprime) to base a.

Properties
The motivation for this definition is the fact that all prime numbers n satisfy the above equation, as explained in the Euler's criterion article. The equation can be tested rather quickly, which can be used for probabilistic primality testing. These tests are over twice as strong as tests based on Fermat's little theorem.

Every Euler–Jacobi pseudoprime is also a Fermat pseudoprime and an Euler pseudoprime. There are no numbers which are Euler–Jacobi pseudoprimes to all bases as Carmichael numbers are. Solovay and Strassen showed that for every composite n, for at least n/2 bases less than n, n is not an Euler–Jacobi pseudoprime.

The smallest Euler–Jacobi pseudoprime base 2 is 561. There are 11347 Euler–Jacobi pseudoprimes base 2 that are less than 25·109 (see ) (page 1005 of ).

In the literature (for example, ), an Euler–Jacobi pseudoprime as defined above is often called simply an Euler pseudoprime.

Implementation in Lua
function EulerJacobiTest(k) a = 2 if k == 1 then return false elseif k == 2 then return true else if(modPow(a,(k-1)/2,k) == Jacobi(a,k)) then return true else return false end end end

title: Euler–Jacobi pseudoprime


text:
User talk:Agur Kesalat

Hello there Birnuson, welcome to the 'pedia! I hope you like the place and decide to stay. If you ever need editing help visit How does one edit a page and experiment at Sandbox. If you need pointers on how we title pages visit Naming conventions or how to format them visit our manual of style. If you have any other questions about the project then check out Help or add a question to the Village pump. BTW, nice work on the Iceland-related articles. Cheers! --maveric149

Nice four year break :)
Good edits to Icelandic subjects! Haukur 14:45, 9 June 2006 (UTC)

WikiProject Iceland
Maybe you are interested in this project... --Michkalas 14:40, 26 April 2007 (UTC)

Skál!

 * Thanks, that was nice! By the way, I'm not finished with the article. It has numerous issues and needs to be expanded considerably. I have plans to do that over the next few weeks. Birnuson (talk) 17:37, 9 October 2013 (UTC)

October 2013
Hello, I'm BracketBot. I have automatically detected that [//en.wikipedia.org/w/index.php?diff=576738669 your edit] to Tjörnin may have broken the syntax by modifying 1 ""s. If you have, don't worry: just [ edit the page] again to fix it. If I misunderstood what happened, or if you have any questions, you can leave a message on [//en.wikipedia.org/w/index.php?action=edit&preload=User:A930913/BBpreload&editintro=User:A930913/BBeditintro&minor=&title=User_talk:A930913&preloadtitle=BracketBot%20-%20&section=new my operator's talk page].
 * List of unpaired brackets remaining on the page:

Thanks, BracketBot (talk) 16:20, 11 October 2013 (UTC)
 * ], as well as the Parliament building, which houses the Parliament of Iceland, and the Dómkirkja cathedral, {{cite book|title=Europe on a

Official language in Iceland
Hello, following [//fr.wikipedia.org/w/index.php?title=Islande&diff=97167897&oldid=prev your contribution], this subject is being discussed on the French Village pump: you may want to give your input there. Regards: Oliv0 (talk) 17:40, 6 November 2013 (UTC)

Disambiguation link notification for April 16
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ArbCom elections are now open!
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title: User talk:Agur Kesalat


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High-temperature superconductivity

High-temperature superconductors (high-$T$c or HTS) are defined as materials with critical temperature (the temperature below which the material behaves as a superconductor) above 77 K, the boiling point of liquid nitrogen. They are only "high-temperature" relative to previously known superconductors, which function at even colder temperatures, close to absolute zero. The "high temperatures" are still far below ambient (room temperature), and therefore require cooling. The first breakthrough of high-temperature superconductor was discovered in 1986 by IBM researchers Georg Bednorz and K. Alex Müller. Although the critical temperature is around 35.1 K, this new type of superconductor was readily modified by Ching-Wu Chu to make the first high-temperature superconductor with critical temperature 93 K. Bednorz and Müller were awarded the Nobel Prize in Physics in 1987 "for their important break-through in the discovery of superconductivity in ceramic materials". Most high-$T$c materials are type-II superconductors.

The major advantage of high-temperature superconductors is that they can be cooled using liquid nitrogen, in contrast to the previously known superconductors that require expensive and hard-to-handle coolants, primarily liquid helium. A second advantage of high-$T$c materials is they retain their superconductivity in higher magnetic fields than previous materials. This is important when constructing superconducting magnets, a primary application of high-$T$c materials.

The majority of high-temperature superconductors are ceramic materials, rather than the previously known metallic materials. Ceramic superconductors are suitable for some practical uses but they still have many manufacturing issues. For example, most ceramics are brittle, which makes the fabrication of wires from them very problematic. However, overcoming these drawbacks is the subject of considerable research, and progress is ongoing.

The main class of high-temperature superconductors is copper oxides combined with other metals, especially the rare-earth barium copper oxides (REBCOs) such as yttrium barium copper oxide (YBCO). The second class of high-temperature superconductors in the practical classification is the iron-based compounds. Magnesium diboride is sometimes included in high-temperature superconductors: It is relatively simple to manufacture, but it superconducts only below 39 K, which makes it unsuitable for liquid nitrogen cooling. Some extremely high-pressure superhydride compounds are usually categorized as high-temperature superconductors. In fact, many articles on high-temperature superconductors can be found on this research on high-pressure gases, which are not suitable for practical applications. The current $T$c record holder is claimed to be carbonaceous sulfur hydride, however superconductivity in these compounds has come under question, and the discovery paper has been retracted due to credible accusations of data manipulation.

History

Superconductivity was discovered by Kamerlingh Onnes in 1911, in a metal solid. Ever since, researchers have attempted to observe superconductivity at increasing temperatures with the goal of finding a room-temperature superconductor. By the late 1970s, superconductivity was observed in several metallic compounds (in particular Nb-based, such as NbTi, Nb3Sn, and Nb3Ge) at temperatures that were much higher than those for elemental metals and which could even exceed 20 K.

In 1986, at the IBM research lab near Zürich in Switzerland, Bednorz and Müller were looking for superconductivity in a new class of ceramics: the copper oxides, or cuprates.

Bednorz encountered a particular copper oxide whose resistance dropped to zero at a temperature around -238 C. Their results were soon confirmed by many groups, notably Paul Chu at the University of Houston and Shoji Tanaka at the University of Tokyo.

In 1987, Philip W. Anderson gave the first theoretical description of these materials, based on the resonating valence bond (RVB) theory, but a full understanding of these materials is still developing today. These superconductors are now known to possess a d-wave pair symmetry. The first proposal that high-temperature cuprate superconductivity involves d-wave pairing was made in 1987 by N. E. Bickers, Douglas James Scalapino and R. T. Scalettar, followed by three subsequent theories in 1988 by Masahiko Inui, Sebastian Doniach, Peter J. Hirschfeld and Andrei E. Ruckenstein, using spin-fluctuation theory, and by Claudius Gros, Didier Poilblanc, Maurice T. Rice and FC. Zhang, and by Gabriel Kotliar and Jialin Liu identifying d-wave pairing as a natural consequence of the RVB theory. The confirmation of the d-wave nature of the cuprate superconductors was made by a variety of experiments, including the direct observation of the d-wave nodes in the excitation spectrum through angle resolved photoemission spectroscopy (ARPES), the observation of a half-integer flux in tunneling experiments, and indirectly from the temperature dependence of the penetration depth, specific heat and thermal conductivity.

As of 2021, the superconductor with the highest transition temperature at ambient pressure is the cuprate of mercury, barium, and calcium, at around 133 K. There are other superconductors with higher recorded transition temperatures – for example lanthanum superhydride at 250 K, but these only occur at very high pressures.

The origin of high-temperature superconductivity is still not clear, but it seems that instead of electron–phonon attraction mechanisms, as in conventional superconductivity, one is dealing with genuine electronic mechanisms (e.g. by antiferromagnetic correlations), and instead of conventional, purely s-wave pairing, more exotic pairing symmetries are thought to be involved (d-wave in the case of the cuprates; primarily extended s-wave, but occasionally d-wave, in the case of the iron-based superconductors).

In 2014, evidence showing that fractional particles can happen in quasi two-dimensional magnetic materials, was found by École Polytechnique Fédérale de Lausanne (EPFL) scientists lending support for Anderson's theory of high-temperature superconductivity.

Properties
The "high-temperature" superconductor class has had many definitions.

The label high-$T$c should be reserved for materials with critical temperatures greater than the boiling point of liquid nitrogen. However, a number of materials – including the original discovery and recently discovered pnictide superconductors – have critical temperatures below 77 K but nonetheless are commonly referred to in publications as high-$T$c class.

A substance with a critical temperature above the boiling point of liquid nitrogen, together with a high critical magnetic field and critical current density (above which superconductivity is destroyed), would greatly benefit technological applications. In magnet applications, the high critical magnetic field may prove more valuable than the high $c$c itself. Some cuprates have an upper critical field of about 100 tesla. However, cuprate materials are brittle ceramics that are expensive to manufacture and not easily turned into wires or other useful shapes. Furthermore, high-temperature superconductors do not form large, continuous superconducting domains, rather clusters of microdomains within which superconductivity occurs. They are therefore unsuitable for applications requiring actual superconductive currents, such as magnets for magnetic resonance spectrometers. For a solution to this (powders), see HTS wire.

There has been considerable debate regarding high-temperature superconductivity coexisting with magnetic ordering in YBCO, iron-based superconductors, several ruthenocuprates and other exotic superconductors, and the search continues for other families of materials. HTS are Type-II superconductors, which allow magnetic fields to penetrate their interior in quantized units of flux, meaning that much higher magnetic fields are required to suppress superconductivity. The layered structure also gives a directional dependence to the magnetic field response.

All known high-$T$c superconductors are Type-II superconductors. In contrast to Type-I superconductors, which expel all magnetic fields due to the Meissner effect, Type-II superconductors allow magnetic fields to penetrate their interior in quantized units of flux, creating "holes" or "tubes" of normal metallic regions in the superconducting bulk called vortices. Consequently, high-$T$c superconductors can sustain much higher magnetic fields.

Cuprates

Cuprates are layered materials, consisting of superconducting layers of copper oxide, separated by spacer layers. Cuprates generally have a structure close to that of a two-dimensional material. Their superconducting properties are determined by electrons moving within weakly coupled copper-oxide (CuO2) layers. Neighbouring layers contain ions such as lanthanum, barium, strontium, or other atoms which act to stabilize the structures and dope electrons or holes onto the copper-oxide layers. The undoped "parent" or "mother" compounds are Mott insulators with long-range antiferromagnetic order at sufficiently low temperatures. Single band models are generally considered to be enough to describe the electronic properties.

The cuprate superconductors adopt a perovskite structure. The copper-oxide planes are checkerboard lattices with squares of O2− ions with a Cu2+ ion at the centre of each square. The unit cell is rotated by 45° from these squares. Chemical formulae of superconducting materials generally contain fractional numbers to describe the doping required for superconductivity. There are several families of cuprate superconductors and they can be categorized by the elements they contain and the number of adjacent copper-oxide layers in each superconducting block. For example, YBCO and BSCCO can alternatively be referred to as "Y123" and Bi2201/Bi2212/Bi2223 depending on the number of layers in each superconducting block ($T$). The superconducting transition temperature has been found to peak at an optimal doping value ($T$=0.16) and an optimal number of layers in each superconducting block, typically $T$=3.

Possible mechanisms for superconductivity in the cuprates continue to be the subject of considerable debate and further research. Certain aspects common to all materials have been identified. Similarities between the antiferromagnetic the low-temperature state of undoped materials and the superconducting state that emerges upon doping, primarily the $T$x2−y2 orbital state of the Cu2+ ions, suggest that electron–electron interactions are more significant than electron–phonon interactions in cuprates – making the superconductivity unconventional. Recent work on the Fermi surface has shown that nesting occurs at four points in the antiferromagnetic Brillouin zone where spin waves exist and that the superconducting energy gap is larger at these points. The weak isotope effects observed for most cuprates contrast with conventional superconductors that are well described by BCS theory.

Similarities and differences in the properties of hole-doped and electron doped cuprates:
 * Presence of a pseudogap phase up to at least optimal doping.
 * Different trends in the Uemura plot relating transition temperature to the superfluid density. The inverse square of the London penetration depth appears to be proportional to the critical temperature for a large number of underdoped cuprate superconductors, but the constant of proportionality is different for hole- and electron-doped cuprates. The linear trend implies that the physics of these materials is strongly two-dimensional.
 * Universal hourglass-shaped feature in the spin excitations of cuprates measured using inelastic neutron diffraction.
 * Nernst effect evident in both the superconducting and pseudogap phases.

The electronic structure of superconducting cuprates is highly anisotropic (see the crystal structure of YBCO or BSCCO). Therefore, the Fermi surface of HTSC is very close to the Fermi surface of the doped CuO2 plane (or multi-planes, in case of multi-layer cuprates) and can be presented on the 2‑D reciprocal space (or momentum space) of the CuO2 lattice. The typical Fermi surface within the first CuO2 Brillouin zone is sketched in Fig. 1 (left). It can be derived from the band structure calculations or measured by angle resolved photoemission spectroscopy (ARPES). Fig. 1 (right) shows the Fermi surface of BSCCO measured by ARPES. In a wide range of charge carrier concentration (doping level), in which the hole-doped HTSC are superconducting, the Fermi surface is hole-like (i.e. open, as shown in Fig. 1). This results in an inherent in-plane anisotropy of the electronic properties of HTSC. In 2018, the full three dimensional Fermi surface structure was derived from soft x-ray ARPES.

Iron-based

Iron-based superconductors contain layers of iron and a pnictogen – such as arsenic or phosphorus – or a chalcogen. This is currently the family with the second highest critical temperature, behind the cuprates. Interest in their superconducting properties began in 2006 with the discovery of superconductivity in LaFePO at 4 K and gained much greater attention in 2008 after the analogous material LaFeAs(O,F) was found to superconduct at up to 43 K under pressure. The highest critical temperatures in the iron-based superconductor family exist in thin films of FeSe,  where a critical temperature in excess of 100 K was reported in 2014.

Since the original discoveries several families of iron-based superconductors have emerged:
 * LnFeAs(O,F) or LnFeAsO1−x (Ln=lanthanide) with $T$c up to 56 K, referred to as 1111 materials. A fluoride variant of these materials was subsequently found with similar $n$c values.
 * (Ba,K)Fe2As2 and related materials with pairs of iron-arsenide layers, referred to as 122 compounds. $p$c values range up to 38 K. These materials also superconduct when iron is replaced with cobalt.
 * LiFeAs and NaFeAs with $n$c up to around 20 K. These materials superconduct close to stoichiometric composition and are referred to as 111 compounds.
 * FeSe with small off-stoichiometry or tellurium doping.

Most undoped iron-based superconductors show a tetragonal-orthorhombic structural phase transition followed at lower temperature by magnetic ordering, similar to the cuprate superconductors. However, they are poor metals rather than Mott insulators and have five bands at the Fermi surface rather than one. The phase diagram emerging as the iron-arsenide layers are doped is remarkably similar, with the superconducting phase close to or overlapping the magnetic phase. Strong evidence that the $p$c value varies with the As–Fe–As bond angles has already emerged and shows that the optimal $n$c value is obtained with undistorted FeAs4 tetrahedra. The symmetry of the pairing wavefunction is still widely debated, but an extended s-wave scenario is currently favoured.

Magnesium diboride
Magnesium diboride is occasionally referred to as a high-temperature superconductor because its $d$c value of 39 K is above that historically expected for BCS superconductors. However, it is more generally regarded as the highest $T$c conventional superconductor, the increased $T$c resulting from two separate bands being present at the Fermi level.

Carbon-based
In 1991 Hebard et al. discovered Fulleride superconductors, where alkali-metal atoms are intercalated into C60 molecules.

In 2008 Ganin et al. demonstrated superconductivity at temperatures of up to 38 K for Cs3C60.

P-doped Graphane was proposed in 2010 to be capable of sustaining high-temperature superconductivity.

On 31st of December 2023 "Global Room-Temperature Superconductivity in Graphite" was published in the journal "Advanced Quantum Technologies" claiming to demonstrate superconductivity at room temperature and ambient pressure in Highly oriented pyrolytic graphite with dense arrays of nearly parallel line defects.

Nickelates
In 1999, Anisimov et al. conjectured superconductivity in nickelates, proposing nickel oxides as direct analogs to the cuprate superconductors. Superconductivity in an infinite-layer nickelate, Nd0.8Sr0.2NiO2, was reported at the end of 2019 with a superconducting transition temperature between 9 and 15 K. This superconducting phase is observed in oxygen-reduced thin films created by the pulsed laser deposition of Nd0.8Sr0.2NiO3 onto SrTiO3 substrates that is then reduced to Nd0.8Sr0.2NiO2 via annealing the thin films at 260 - 280 C in the presence of CaH2. The superconducting phase is only observed in the oxygen reduced film and is not seen in oxygen reduced bulk material of the same stoichiometry, suggesting that the strain induced by the oxygen reduction of the Nd0.8Sr0.2NiO2 thin film changes the phase space to allow for superconductivity. Of important is further to extract access hydrogen from the reduction with CaH2, otherwise topotactic hydrogen may prevent superconductivity.

Cuprates
The structure of cuprates which are superconductors are often closely related to perovskite structure, and the structure of these compounds has been described as a distorted, oxygen deficient multi-layered perovskite structure. One of the properties of the crystal structure of oxide superconductors is an alternating multi-layer of CuO2 planes with superconductivity taking place between these layers. The more layers of CuO2, the higher $T$c. This structure causes a large anisotropy in normal conducting and superconducting properties, since electrical currents are carried by holes induced in the oxygen sites of the CuO2 sheets. The electrical conduction is highly anisotropic, with a much higher conductivity parallel to the CuO2 plane than in the perpendicular direction. Generally, critical temperatures depend on the chemical compositions, cations substitutions and oxygen content. They can be classified as superstripes; i.e., particular realizations of superlattices at atomic limit made of superconducting atomic layers, wires, dots separated by spacer layers, that gives multiband and multigap superconductivity.

Yttrium–barium cuprate
An yttrium–barium cuprate, YBa2Cu3O7−x (or Y123), was the first superconductor found above liquid nitrogen boiling point. There are two atoms of Barium for each atom of Yttrium. The proportions of the three different metals in the YBa2Cu3O7 superconductor are in the mole ratio of 1 to 2 to 3 for yttrium to barium to copper, respectively: this particular superconductor has also often been referred to as the 123 superconductor.

The unit cell of YBa2Cu3O7 consists of three perovskite unit cells, which is pseudocubic, nearly orthorhombic. The other superconducting cuprates have another structure: they have a tetragonal cell. Each perovskite cell contains a Y or Ba atom at the center: Ba in the bottom unit cell, Y in the middle one, and Ba in the top unit cell. Thus, Y and Ba are stacked in the sequence [Ba–Y–Ba] along the c-axis. All corner sites of the unit cell are occupied by Cu, which has two different coordinations, Cu(1) and Cu(2), with respect to oxygen. There are four possible crystallographic sites for oxygen: O(1), O(2), O(3) and O(4). The coordination polyhedra of Y and Ba with respect to oxygen are different. The tripling of the perovskite unit cell leads to nine oxygen atoms, whereas YBa2Cu3O7 has seven oxygen atoms and, therefore, is referred to as an oxygen-deficient perovskite structure. The structure has a stacking of different layers: (CuO)(BaO)(CuO2)(Y)(CuO2)(BaO)(CuO). One of the key feature of the unit cell of YBa2Cu3O7−x (YBCO) is the presence of two layers of CuO2. The role of the Y plane is to serve as a spacer between two CuO2 planes. In YBCO, the Cu–O chains are known to play an important role for superconductivity. $T$c is maximal near 92 K when x ≈ 0.15 and the structure is orthorhombic. Superconductivity disappears at x ≈ 0.6, where the structural transformation of YBCO occurs from orthorhombic to tetragonal.

Other cuprates
The preparation of other cuprates is more difficult than the YBCO preparation. They also have a different crystal structure: they are tetragonal where YBCO is orthorhombic. Problems in these superconductors arise because of the existence of three or more phases having a similar layered structure. Moreover, the crystal structure of other tested cuprate superconductors are very similar. Like YBCO, the perovskite-type feature and the presence of simple copper oxide (CuO2) layers also exist in these superconductors. However, unlike YBCO, Cu–O chains are not present in these superconductors. The YBCO superconductor has an orthorhombic structure, whereas the other high-$T$c superconductors have a tetragonal structure.

There are three main classes of superconducting cuprates: bismuth-based, thallium-based and mercury-based.

The second cuprate by practical importance is currently BSCCO, a compound of Bi–Sr–Ca–Cu–O. The content of bismuth and strontium creates some chemical issues. It has three superconducting phases forming a homologous series as Bi2Sr2Can−1CunO4+2n+x (n=1, 2 and 3). These three phases are Bi-2201, Bi-2212 and Bi-2223, having transition temperatures of 20 K, 85 K and 110 K, respectively, where the numbering system represent number of atoms for Bi Sr, Ca and Cu respectively. The two phases have a tetragonal structure which consists of two sheared crystallographic unit cells. The unit cell of these phases has double Bi–O planes which are stacked in a way that the Bi atom of one plane sits below the oxygen atom of the next consecutive plane. The Ca atom forms a layer within the interior of the CuO2 layers in both Bi-2212 and Bi-2223; there is no Ca layer in the Bi-2201 phase. The three phases differ with each other in the number of cuprate planes; Bi-2201, Bi-2212 and Bi-2223 phases have one, two and three CuO2 planes, respectively. The c axis lattice constants of these phases increases with the number of cuprate planes (see table below). The coordination of the Cu atom is different in the three phases. The Cu atom forms an octahedral coordination with respect to oxygen atoms in the 2201 phase, whereas in 2212, the Cu atom is surrounded by five oxygen atoms in a pyramidal arrangement. In the 2223 structure, Cu has two coordinations with respect to oxygen: one Cu atom is bonded with four oxygen atoms in square planar configuration and another Cu atom is coordinated with five oxygen atoms in a pyramidal arrangement.

Cuprate of Tl–Ba–Ca: The first series of the Tl-based superconductor containing one Tl–O layer has the general formula TlBa2Can−1CunO2n+3, whereas the second series containing two Tl–O layers has a formula of Tl2Ba2Can−1CunO2n+4 with n =1, 2 and 3. In the structure of Tl2Ba2CuO6 (Tl-2201), there is one CuO2 layer with the stacking sequence (Tl–O) (Tl–O) (Ba–O) (Cu–O) (Ba–O) (Tl–O) (Tl–O). In Tl2Ba2CaCu2O8 (Tl-2212), there are two Cu–O layers with a Ca layer in between. Similar to the Tl2Ba2CuO6 structure, Tl–O layers are present outside the Ba–O layers. In Tl2Ba2Ca2Cu3O10 (Tl-2223), there are three CuO 2 layers enclosing Ca layers between each of these. In Tl-based superconductors, $T$c is found to increase with the increase in CuO2 layers. However, the value of $T$c decreases after four CuO2 layers in TlBa2Can−1CunO2n+3, and in the Tl2Ba2Can−1CunO2n+4 compound, it decreases after three CuO2 layers.

Cuprate of Hg–Ba–Ca The crystal structure of HgBa2CuO4 (Hg-1201), HgBa2CaCu2O6 (Hg-1212) and HgBa2Ca2Cu3O8 (Hg-1223) is similar to that of Tl-1201, Tl-1212 and Tl-1223, with Hg in place of Tl. It is noteworthy that the $T$c of the Hg compound (Hg-1201) containing one CuO2 layer is much larger as compared to the one-CuO2-layer compound of thallium (Tl-1201). In the Hg-based superconductor, $T$c is also found to increase as the CuO2 layer increases. For Hg-1201, Hg-1212 and Hg-1223, the values of $T$c are 94, 128, and the record value at ambient pressure 134 K, respectively, as shown in table below. The observation that the $T$c of Hg-1223 increases to 153 K under high pressure indicates that the $T$c of this compound is very sensitive to the structure of the compound.

Preparation and manufacturing
The simplest method for preparing ceramic superconductors is a solid-state thermochemical reaction involving mixing, calcination and sintering. The appropriate amounts of precursor powders, usually oxides and carbonates, are mixed thoroughly using a Ball mill. Solution chemistry processes such as coprecipitation, freeze-drying and sol–gel methods are alternative ways for preparing a homogeneous mixture. These powders are calcined in the temperature range from 800 to 950 C for several hours. The powders are cooled, reground and calcined again. This process is repeated several times to get homogeneous material. The powders are subsequently compacted to pellets and sintered. The sintering environment such as temperature, annealing time, atmosphere and cooling rate play a very important role in getting good high-$T$c superconducting materials. The YBa2Cu3O7−x compound is prepared by calcination and sintering of a homogeneous mixture of Y2O3, BaCO3 and CuO in the appropriate atomic ratio. Calcination is done at 800 to 950 C, whereas sintering is done at 950 C in an oxygen atmosphere. The oxygen stoichiometry in this material is very crucial for obtaining a superconducting YBa2Cu3O7−x compound. At the time of sintering, the semiconducting tetragonal YBa2Cu3O6 compound is formed, which, on slow cooling in oxygen atmosphere, turns into superconducting YBa2Cu3O7−x. The uptake and loss of oxygen are reversible in YBa2Cu3O7−x. A fully oxygenated orthorhombic YBa2Cu3O7−x sample can be transformed into tetragonal YBa2Cu3O6 by heating in a vacuum at temperature above 700 C.

The preparation of Bi-, Tl- and Hg-based high-$T$c superconductors is more difficult than the YBCO preparation. Problems in these superconductors arise because of the existence of three or more phases having a similar layered structure. Thus, syntactic intergrowth and defects such as stacking faults occur during synthesis and it becomes difficult to isolate a single superconducting phase. For Bi–Sr–Ca–Cu–O, it is relatively simple to prepare the Bi-2212 ($T$c ≈ 85 K) phase, whereas it is very difficult to prepare a single phase of Bi-2223 ($T$c ≈ 110 K). The Bi-2212 phase appears only after few hours of sintering at 860 - 870 C, but the larger fraction of the Bi-2223 phase is formed after a long reaction time of more than a week at 870 C. Although the substitution of Pb in the Bi–Sr–Ca–Cu–O compound has been found to promote the growth of the high-$T$c phase, a long sintering time is still required.

Ongoing research
The question of how superconductivity arises in high-temperature superconductors is one of the major unsolved problems of theoretical condensed matter physics. The mechanism that causes the electrons in these crystals to form pairs is not known. Despite intensive research and many promising leads, an explanation has so far eluded scientists. One reason for this is that the materials in question are generally very complex, multi-layered crystals (for example, BSCCO), making theoretical modelling difficult.

Improving the quality and variety of samples also gives rise to considerable research, both with the aim of improved characterisation of the physical properties of existing compounds, and synthesizing new materials, often with the hope of increasing $T$c. Technological research focuses on making HTS materials in sufficient quantities to make their use economically viable as well as in optimizing their properties in relation to applications. Metallic hydrogen has been proposed as a room-temperature superconductor, some experimental observations have detected the occurrence of the Meissner effect. LK-99, copper-doped lead-apatite, has also been proposed as a room-temperature superconductor.

Theoretical models
There have been two representative theories for high-temperature or unconventional superconductivity. Firstly, weak coupling theory suggests superconductivity emerges from antiferromagnetic spin fluctuations in a doped system. According to this theory, the pairing wave function of the cuprate HTS should have a dx2-y2 symmetry. Thus, determining whether the pairing wave function has d-wave symmetry is essential to test the spin fluctuation mechanism. That is, if the HTS order parameter (a pairing wave function like in Ginzburg–Landau theory) does not have d-wave symmetry, then a pairing mechanism related to spin fluctuations can be ruled out. (Similar arguments can be made for iron-based superconductors but the different material properties allow a different pairing symmetry.) Secondly, there was the interlayer coupling model, according to which a layered structure consisting of BCS-type (s-wave symmetry) superconductors can enhance the superconductivity by itself. By introducing an additional tunnelling interaction between each layer, this model successfully explained the anisotropic symmetry of the order parameter as well as the emergence of the HTS. Thus, in order to solve this unsettled problem, there have been numerous experiments such as photoemission spectroscopy, NMR, specific heat measurements, etc. Up to date the results were ambiguous, some reports supported the d symmetry for the HTS whereas others supported the s symmetry. This muddy situation possibly originated from the indirect nature of the experimental evidence, as well as experimental issues such as sample quality, impurity scattering, twinning, etc.

This summary makes an implicit assumption: superconductive properties can be treated by mean-field theory. It also fails to mention that in addition to the superconductive gap, there is a second gap, the pseudogap. The cuprate layers are insulating, and the superconductors are doped with interlayer impurities to make them metallic. The superconductive transition temperature can be maximized by varying the dopant concentration. The simplest example is La2CuO4, which consist of alternating CuO2 and LaO layers which are insulating when pure. When 8% of the La is replaced by Sr, the latter act as dopants, contributing holes to the CuO2 layers, and making the sample metallic. The Sr impurities also act as electronic bridges, enabling interlayer coupling. Proceeding from this picture, some theories argue that the basic pairing interaction is still interaction with phonons, as in the conventional superconductors with Cooper pairs. While the undoped materials are antiferromagnetic, even a few percent of impurity dopants introduce a smaller pseudogap in the CuO2 planes which is also caused by phonons. The gap decreases with increasing charge carriers, and as it nears the superconductive gap, the latter reaches its maximum. The reason for the high transition temperature is then argued to be due to the percolating behaviour of the carriers – the carriers follow zig-zag percolative paths, largely in metallic domains in the CuO2 planes, until blocked by charge density wave domain walls, where they use dopant bridges to cross over to a metallic domain of an adjacent CuO2 plane. The transition temperature maxima are reached when the host lattice has weak bond-bending forces, which produce strong electron–phonon interactions at the interlayer dopants.

D symmetry in YBCO

An experiment based on flux quantization of a three-grain ring of YBa2Cu3O7 (YBCO) was proposed to test the symmetry of the order parameter in the HTS. The symmetry of the order parameter could best be probed at the junction interface as the Cooper pairs tunnel across a Josephson junction or weak link. It was expected that a half-integer flux, that is, a spontaneous magnetization could only occur for a junction of d symmetry superconductors. But, even if the junction experiment is the strongest method to determine the symmetry of the HTS order parameter, the results have been ambiguous. John R. Kirtley and C. C. Tsuei thought that the ambiguous results came from the defects inside the HTS, so that they designed an experiment where both clean limit (no defects) and dirty limit (maximal defects) were considered simultaneously. In the experiment, the spontaneous magnetization was clearly observed in YBCO, which supported the d symmetry of the order parameter in YBCO. But, since YBCO is orthorhombic, it might inherently have an admixture of s symmetry. So, by tuning their technique further, they found that there was an admixture of s symmetry in YBCO within about 3%. Also, they found that there was a pure dx2−y2 order parameter symmetry in the tetragonal Tl2Ba2CuO6.

Spin-fluctuation mechanism
Despite all these years, the mechanism of high-$T$c superconductivity is still highly controversial, mostly due to the lack of exact theoretical computations on such strongly interacting electron systems. However, most rigorous theoretical calculations, including phenomenological and diagrammatic approaches, converge on magnetic fluctuations as the pairing mechanism for these systems. The qualitative explanation is as follows:

In a superconductor, the flow of electrons cannot be resolved into individual electrons, but instead consists of many pairs of bound electrons, called Cooper pairs. In conventional superconductors, these pairs are formed when an electron moving through the material distorts the surrounding crystal lattice, which in turn attracts another electron and forms a bound pair. This is sometimes called the "water bed" effect. Each Cooper pair requires a certain minimum energy to be displaced, and if the thermal fluctuations in the crystal lattice are smaller than this energy the pair can flow without dissipating energy. This ability of the electrons to flow without resistance leads to superconductivity.

In a high-$T$c superconductor, the mechanism is extremely similar to a conventional superconductor, except, in this case, phonons virtually play no role and their role is replaced by spin-density waves. Just as all known conventional superconductors are strong phonon systems, all known high-$T$c superconductors are strong spin-density wave systems, within close vicinity of a magnetic transition to, for example, an antiferromagnet. When an electron moves in a high-$T$c superconductor, its spin creates a spin-density wave around it. This spin-density wave in turn causes a nearby electron to fall into the spin depression created by the first electron (water-bed effect again). Hence, again, a Cooper pair is formed. When the system temperature is lowered, more spin density waves and Cooper pairs are created, eventually leading to superconductivity. Note that in high-$2$c systems, as these systems are magnetic systems due to the Coulomb interaction, there is a strong Coulomb repulsion between electrons. This Coulomb repulsion prevents pairing of the Cooper pairs on the same lattice site. The pairing of the electrons occur at near-neighbor lattice sites as a result. This is the so-called d-wave pairing, where the pairing state has a node (zero) at the origin.

Examples
Examples of high-$T$c cuprate superconductors include YBCO and BSCCO, which are the most known materials that achieve superconductivity above the boiling point of liquid nitrogen.

title: High-temperature superconductivity