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<center>'''"Share your knowledge. It's a way to achieve immortality."'''</center>
<center>&mdash;Jackson Brown and H. Jackson Brown, Jr., ''Life's Little Instruction Book''</center>
<center>'''"The ink of the learned is equal in merit to the blood of the martyrs."'''</center>
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<center>'''"Knowledge is the true organ of sight, not the eyes."'''</center>
<center>&mdash;From the [[Panchatantra|Panchatantra]] [http://www.britannica.com/EBchecked/topic/440899/Panchatantra (Indian literature)]</center>
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<center>'''"Knowledge is the true organ of sight, not the eyes."'''</center>
<center>&mdash;From the [[Panchatantra|Panchatantra]] [http://www.britannica.com/EBchecked/topic/440899/Panchatantra (Indian literature)]</center>
<center>'''"The ink of the learned is equal in merit to the blood of the martyrs."'''</center>
<center>&mdash;Father Kristoforos, [http://www.randomhouse.com/catalog/display.pperl?isbn=9781400079322&view=rg ''Birds Without Wings''], by [http://www.contemporarywriters.com/authors/?p=auth2 Louis de Bernières (b. 1954)]</center> -->
<center>'''"Knowledge is the true organ of sight, not the eyes."'''</center>
<center>&mdash;From the [[Panchatantra|Panchatantra]] [http://www.britannica.com/EBchecked/topic/440899/Panchatantra (Indian literature)]</center>
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=== Article of the Week <font size=1>[ [[CZ:Article of the Week|about]] ]</font> ===
{{Image|Anthracite coal.jpg|right|275px|Anthracite coal (coin shown for scale).}}


'''Coal''' is a [[Carbon|carbon-containing]] rock formed by the debris from the decay of ferns, vines, trees and other plants which flourished in swamps millions of years ago. Over time, the debris became buried and the actions of [[bacteria]], [[heat]] and [[pressure]] transformed the debris first into [[peat]] (a precursor of coal) and then into the various types of coal as we know them today.<ref name=Perry>{{cite book|author=Green, Don W. and Perry, Robert H. (Editors)|title=Perry's Chemical Engineers' Handbook|edition=6th Edition|publisher=McGraw-Hill|year=1997|id=ISBN 0-07-049479-7}}</ref><ref name=Marks>{{cite book|author=Eugene A. Avallone, Theodore Baumeister and Ali Sadegh (Editors)|title=Marks' Standard Handbook for Mechanical Engineers|edition=11th Edition|publisher=McGraw-Hill Professional|year=2006|id=ISBN 0-07-142867-4}}</ref><ref name=Kreith>{{cite book|author=Frank Kreith (Editor)|title=The CRC Handbook of Mechanical Engineering|edition=1st Edition|publisher=CRC Press|year=1998|id=ISBN 0-8493-9418-X}}</ref> In more technical terminology, that process of transformation is referred to as ''metamorphosis'', ''coalification'' or ''lithification''.


Coal is extracted by [[mine (resource extraction)|mining]] from deposits that exist deep underground as well as deposits that are essentially at or near the surface of the ground. Because of the various degrees of transformation that occurred during the forming of coal deposits in different locations, the composition of coal varies from one deposit to another. No two coals are the same in every respect. In general, coal consists of [[carbon]], [[hydrogen]], [[oxygen]], [[nitrogen]], [[sulfur]] and [[mineral]] matter (including compounds of [[silicon]], [[aluminum]], [[iron]], [[calcium]], [[magnesium]] and others).<font size=1>[[Coal|['''more...''']]]</font>


=== New Draft of the Week <font size=1>[ [[CZ:New Draft of the Week|about]] ]</font> ===
'''Gasoline''' or '''petrol''' is a fuel, derived from [[petroleum crude oil]], for use in spark-ignited [[internal combustion engine]]s. Conventional gasoline is mostly a blended mixture of more than 200 different [[hydrocarbon]] [[liquid]]s ranging from those containing 4 [[carbon]] [[atom]]s to those containing 11 or 12  carbon atoms. It has an initial [[boiling point]] at [[atmospheric pressure]] of about 35 °[[Celsius|C]] (95 °[[Fahrenheit|F]]) and a final boiling point of about 200 °C (395 °F).<ref name=FAQ>[http://www.faqs.org/faqs/autos/gasoline-faq/part4/ Gasoline FAQ - Part2 of 4], Bruce Hamilton, Industrial Research Ltd. (IRL), a [[Crown Research Institute]] of [[New Zealand]].</ref><ref name=Gary>{{cite book|author=Gary, J.H. and Handwerk, G.E.|title=Petroleum Refining Technology and Economics|edition=4th Edition|publisher=Marcel Dekker, Inc.|year=2001|url=http://books.google.com/books?id=eE3_IqDeeosC&pg=PP1&dq=%22Petroleum+Refining+Technology+and+Economics%22&lr=&as_drrb_is=q&as_minm_is=0&as_miny_is=&as_maxm_is=0&as_maxy_is=&as_brr=0&as_pt=ALLTYPES|id=ISBN 0-8247-0482-7}}</ref><ref name=Assi>[http://hqweb.unep.org/pcfv/PDF/JordanWrkshp-Unleaded-Rafat.pdf The Relation Between Gasoline Quality, Octane Number and the Environment], Rafat Assi, National Project Manager of Jordan’s Second National Communications on Climate Change, presented at ''Jordan National Workshop on Lead Phase-out'', [[United Nations Environment Programme]], July 2008, [[Amman]], [[Jordan]].</ref><ref>{{cite book|author=James Speight|title=Synthetic Fuels Handbook|edition=1st Edition|publisher=McGraw-Hill|pages=pages 92-93|year=2008|url=http://books.google.com/books?id=E3pgqnGgHjIC&printsec=frontcover&dq=%22Synthetic+Fuels+Handbook%22&lr=&as_drrb_is=q&as_minm_is=0&as_miny_is=&as_maxm_is=0&as_maxy_is=&as_brr=0&as_pt=ALLTYPES|id=ISBN 0-07-149023-X}}</ref> Gasoline is used primarily as fuel for the internal combustion engines in automotive vehicles as well in some small airplanes.     
In [[Canada]] and the [[United States]], the word "gasoline" is commonly used and it is often shortened to simply "gas" although it is a liquid rather than a [[gas]]. In fact, gasoline-dispensing facilities are referred to as "gas stations".


Most current or former [[Commonwealth of Nations|Commonwealth countries]] use the term "petrol" and their dispensing facilities are referred to as "petrol stations". The term "petrogasoline" is also used sometimes. In some European countries and elsewhere, the term "benzin" (or a variant of that word) is used to denote gasoline.


In aviation, "mogas" (an abbreviation for "motor gasoline") is used to distinguish automotive vehicle fuel from aviation fuel known as "avgas".<font size=1>[[Gasoline/Draft|['''more...''']]]</font>
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<h4 style="margin:0 0 0.75em; padding:0;"> '''Article counts''' </h4>
<p style="line-height:15px; padding-left:20px;">
[[:Category:Citable versions of articles|Citable]] <font size=1>('''{{PAGESINCAT:Citable versions of articles}}''')</font><br />
[[:Category:Developed Articles|Developed]] <font size=1>('''{{PAGESINCAT:Developed Articles}}''')</font><br />
[[:Category:Developing Articles|Developing]] <font size=1>('''{{PAGESINCAT:Developing Articles}}''')</font><br />
[[:Category:Stub Articles|Stubs]] <font size=1>('''{{PAGESINCAT:Stub Articles}}''')</font><br />
<small>([[:Category:CZ Live|{{PAGESINCAT:CZ Live}} total]])</small>
</p>
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----<h3 style="margin-top:0; padding-top:0.6em; border-top:1px dotted #e0e0e0;">
<big>[[CZ:Featured article|Featured Article]]: ''[[{{FeaturedArticleTitle}}]]''</big>
</h3>
{{CZ:Featured article/Current}}
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<div style='text-align: right;'><small>''[[{{FeaturedArticleTitle}}|Continued]]...''</small></div>

Latest revision as of 09:47, 31 October 2024

New Blog Post
Why is Citizendium deleting articles?


Help Write Articles about our World

Welcome to Citizendium, a wiki for providing free knowledge where authors use their real names. We regard information as a public good and welcome anyone who wants to share their knowledge on virtually any subject. Our online community prides itself on being congenial and supportive.

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Article counts

Citable (146)
Developed (1,129)
Developing (7,403)
Stubs (7,676)
(16,484 total)

Man's mind stretched to a new idea never goes back to its original dimensions.
— Oliver Wendell Holmes (1809–1894)
       —add a quotation about knowledge or writing


Featured Article: Nuclear power reconsidered

After decades of failure to slow the rising global consumption of coal, oil and gas,[1] many countries have proceeded as of 2024 to reconsider nuclear power in order to lower the demand for fossil fuels.[2] Wind and solar power alone, without large-scale storage for these intermittent sources, are unlikely to meet the world's needs for reliable energy.[3][4][5] See Figures 1 and 2 on the magnitude of the world energy challenge.

Nuclear power plants that use nuclear reactors to create electricity could provide the abundant, zero-carbon, dispatchable[6] energy needed for a low-carbon future, but not by simply building more of what we already have. New innovative designs for nuclear reactors are needed to avoid the problems of the past.

(CC) Image: Geoff Russell
Fig.1 Electricity consumption may soon double, mostly from coal-fired power plants in the developing world.[7]

Issues Confronting the Nuclear Industry

New reactor designers have sought to address issues that have prevented the acceptance of nuclear power, including safety, waste management, weapons proliferation, and cost. This article will summarize the questions that have been raised and the criteria that have been established for evaluating these designs. Answers to these questions will be provided by the designers of these reactors in the articles on their designs. Further debate will be provided in the Discussion and the Debate Guide pages of those articles.

Footnotes

  1. Global Energy Growth by Our World In Data
  2. Countries, organizations, and public figures that have reconsidered their stance on nuclear power are listed on the External Links tab of this article.
  3. Pumped storage is currently the most economical way to store electricity, but it requires a large reservoir on a nearby hill or in an abandoned mine. Li-ion battery systems at $500 per KWh are not practical for utility-scale storage. See Energy Storage for a summary of other alternatives.
  4. Utilities that include wind and solar power in their grid must have non-intermittent generating capacity (typically fossil fuels) to handle maximum demand for several days. They can save on fuel, but the cost of the plant is the same with or without intermittent sources.
  5. Mark Jacobson believes that long-distance transmission lines can provide an alternative to costly storage. See the bibliography for more on this proposal and the critique by Christopher Clack.
  6. "Load following" is the term used by utilities, and is important when there is a lot of wind and solar on the grid. Some reactors are not able to do this.
  7. Fig.1.3 in Devanney "Why Nuclear Power has been a Flop"