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Heat of combustion

The heating value of a substance a fuel or food, is the amount of heat released during the combustion of a specified amount of it. The calorific value is the total energy released as heat when a substance undergoes complete combustion with oxygen under standard conditions; the chemical reaction is a hydrocarbon or other organic molecule reacting with oxygen to form carbon dioxide and water and release heat. It may be expressed with the quantities: energy/mole of fuel energy/mass of fuel energy/volume of the fuelThere are two kinds of heat of combustion, called higher and lower heating value, depending on how much the products are allowed to cool and whether compounds like H2O are allowed to condense; the values are conventionally measured with a bomb calorimeter. They may be calculated as the difference between the heat of formation ΔH⦵f of the products and reactants. For a fuel of composition CcHhOoNn, the heat of combustion is 418 kJ/mol to a good approximation, though it can be drastically wrong if o + n > c.

The value corresponds to an exothermic reaction because the double bond in molecular oxygen is much weaker than other double bonds or pairs of single bonds those in the combustion products carbon dioxide and water. By convention, the heat of combustion is defined to be the heat released for the complete combustion of a compound in its standard state to form stable products in their standard states: hydrogen is converted to water, carbon is converted to carbon dioxide gas, nitrogen is converted to nitrogen gas; that is, the heat of combustion, ΔH°comb, is the heat of reaction of the following process: CxHyNzOn + O2 → xCO2 + ​y⁄2H2O + ​z⁄2N2 Chlorine and sulfur are not quite standardized. The quantity known as higher heating value is determined by bringing all the products of combustion back to the original pre-combustion temperature, in particular condensing any vapor produced; such measurements use a standard temperature of 25 °C. This is the same as the thermodynamic heat of combustion since the enthalpy change for the reaction assumes a common temperature of the compounds before and after combustion, in which case the water produced by combustion is condensed to a liquid.

The higher heating value takes into account the latent heat of vaporization of water in the combustion products, is useful in calculating heating values for fuels where condensation of the reaction products is practical. In other words, HHV assumes all the water component is in liquid state at the end of combustion and that heat delivered at temperatures below 150 °C can be put to use The quantity known as lower heating value is determined by subtracting the heat of vaporization of the water from the higher heating value; this treats any H2O formed as a vapor. The energy required to vaporize the water therefore is not released as heat. LHV calculations assume that the water component of a combustion process is in vapor state at the end of combustion, as opposed to the higher heating value which assumes that all of the water in a combustion process is in a liquid state after a combustion process; the LHV assumes that the latent heat of vaporization of water in the fuel and the reaction products is not recovered.

It is useful in comparing fuels where condensation of the combustion products is impractical, or heat at a temperature below 150 °C cannot be put to use. The above is but one definition of lower heating value adopted by the American Petroleum Institute and uses a reference temperature of 60 °F. Another definition, used by Gas Processors Suppliers Association and used by API, is the enthalpy of all combustion products minus the enthalpy of the fuel at the reference temperature, minus the enthalpy of the stoichiometric oxygen at the reference temperature, minus the heat of vaporization of the vapor content of the combustion products; the distinction between the two is that this second definition assumes that the combustion products are all returned to the reference temperature and the heat content from the condensing vapor is considered not to be useful. This is more calculated from the higher heating value than when using the preceding definition and will in fact give a different answer. Gross heating value accounts for water in the exhaust leaving as vapor, includes liquid water in the fuel prior to combustion.

This value is important for fuels like wood or coal, which will contain some amount of water prior to burning. The higher heating value is experimentally determined in a bomb calorimeter; the combustion of a stoichiometric mixture of fuel and oxidizer (e.g. two moles o

Science fiction studies

Science fiction studies is the common name for the academic discipline that studies and researches the history and works of science fiction and, more broadly, speculative fiction. The modern field of science fiction studies is related to popular culture studies, a subdiscipline of cultural studies, film and literature studies; because of the ties with futurism and utopian works, there is overlap with these fields as well. The field has spawned subfields, such as feminist science fiction studies. However, the field's roots go back much further, to the earliest commentators who studied representations of the sciences in the arts and literature, explorations of utopian and social reform impulses in fantastic and visionary works of art and literature. Modern science fiction criticism may have started with Dorothy Scarborough, who in 1917 included a chapter on "Supernatural Science" in her doctoral dissertation, published as The Supernatural in Modern English Fiction; as the pulp era progressed, shifting science fiction further into popular culture, groups of writers, editors and fans systematically organized publishing enterprises and other insignia of an academic discipline.

Much discussion about science fiction took place in the letter columns of early SF magazines and fanzines, the first book of commentary on science fiction in the US was Clyde F. Beck's Hammer and Tongs, a chapbook of essays published in a fanzine; the 1940s saw the appearance of three full-scale scholarly works that treated science fiction and its literary ancestors: Philip Babcock Gove's The Imaginary Voyage in Prose Fiction, J. O. Bailey's Pilgrims Through Space and Time, Marjorie Hope Nicholson's Voyages to the Moon. Peter Nicholls credits Sam Moskowitz with teaching "what was certainly the first sf course in the USA to be given through a college": a non-credit course in "Science Fiction Writing" at City College of New York in 1953; the first regular, for-credit courses were taught by Mark Hillegas and H. Bruce Franklin in 1961. During the 1960s, more science fiction scholars began to move into the academy, founding academic journals devoted to the exploration of the literature and works of science fiction.

The explosion of film studies and cultural studies more broadly granted the nascent discipline additional credibility, throughout the 1970s and 1980s, mainstream scholars such as Susan Sontag turned their critical attention to science fiction. In 1982, James Gunn established the Center for the Study of Science Fiction as a Kansas Board of Regents Center as a focus for the SF programs he offered at the University of Kansas, beginning in 1969; this was the first such SF organization at a major university. The 1990s saw the first academic programs and degree-granting programs established, the field shows continued steady growth, not also at technology-oriented institutions. University of Dundee, MLitt in Science Fiction Florida Atlantic University, MA in Literature & Theory with a concentration in Science Fiction and Fantasy University of California, Riverside PhD Designated Emphasis in Science Fiction and Technoculture Studies. University of Kansas, Center for the Study of Science Fiction University of Liverpool, M.

A. in Science Fiction Studies Beijing Normal University, M. A. in Science Fiction Studies Societies: Science Fiction Research Association Society for Utopian Studies International Association for the Fantastic in the Arts Utopian Studies Society London Science Fiction Research Community, London-based organisation of SF scholars and fansGeneral journals: Extrapolation Science Fiction Studies Foundation: The International Review of Science Fiction MOSF Journal of Science Fiction The Eaton Journal of Archival Research in Science Fiction Journal for the Fantastic in the Arts Vector, critical magazine of the British Science Fiction Association Review journals: The Internet Review of Science Fiction New York Review of Science Fiction Conferences: Science Fiction Research Association annual convention International Association for the Fantastic in the Arts annual convention Wiscon Mythcon Eaton Science Fiction Conference, biennial conference at University of California, Riverside Stage the Future conference on science fiction theatreSignificant scholarship awards: "Pilgrim Award", Science Fiction Research Association Pioneer Award for Outstanding Scholarship, Science Fiction Research Association "Distinguished Scholar Award", International Association for the Fantastic in the Arts J. Lloyd Eaton Memorial Award for the best critical book of the year focusing on science fiction Thomas D. Clareson Award for Distinguished Service to the field Kingsley Amis.

New Maps of Hell: A Survey of Science Fiction. New York: Harcourt, 1960. Brian Attebery. Decoding Gender in Science Fiction. New York: Routledge, 2002. Marleen Barr, Alien to Femininity. Westport, CT: Greenwood, 1987. Marleen S. Barr and Carl Freedman, eds. PMLA: Special Topic: Science Fiction and Literary Studies: The Next Millennium. Vol. 119, No. 3, May 2004. Neil Barron, ed. Anatomy of Wonder: Science Fiction. New York: Bowker, 1976. Mark Bould and China Miéville, eds. Red Planets: Marxism and Science

Svetlana Khorkina

Svetlana Vasilyevna Khorkina is a retired Russian artistic gymnast. She competed at the 1996 Summer Olympics, the 2000 Summer Olympics, the 2004 Summer Olympics. During her career, Khorkina won twenty World Championship medals. Over time, she medaled in every event at the World Artistic Gymnastics Championships, she was the first gymnast to win three all-around titles at the World Championships and only the second female artistic gymnast after Nadia Comăneci, to win three European All-Around titles. Svetlana Khorkina is regarded as one of the most successful female gymnasts of all time. At the Opening Ceremony of the 2019 Winter Universiade she lit the fire, together with bandy player Sergey Lomanov. In April 1994, Khorkina competed at the World Championships in Australia, she placed ninth in the all around with a score of 38.805. In the event finals, she placed second on vault scoring 9.800, second on uneven bars scoring 9.875, eighth on floor scoring 8.487. In November 1994, Khorkina competed at the World Team Championships in Germany.

She contributed an all-around score of 39.450 toward the Russian team's third-place finish. In October 1995, Khorkina competed at the World Championships in Japan. In the all around final, she placed second with a score of 39.130. In the event finals, she placed fifth on vault scoring 9.618 and first on uneven bars scoring 9.900. In April 1996, Khorkina competed at the World Championships in Puerto Rico, she placed fifth on vault scoring 9.637 and first on uneven bars scoring 9.787. In May 1996, Khorkina competed at the European Championships in United Kingdom, she helped Russia win the silver medal in the team final and came sixth in the all around final with a score of 38.549. In the event finals, she placed fourth on vault scoring 9.725 and first on uneven bars scoring 9.825. Khorkina competed at the 1996 Summer Olympics in United States. In the team final, she contributed a combined compulsory and optional score of 77.648 toward the Russian team's second-place finish. In the all-around final, she fell on the uneven bars in the final rotation and finished fifteenth in the standings with a total score of 38.455.

Three days Khorkina redeemed herself by winning the gold medal in the uneven bars final with a score of 9.850. In September 1997, Khorkina competed at the World Championships in Switzerland, she helped Russia placed second in the team final and individually she won the all around final with a score of 38.636. In event finals, she placed eighth on vault scoring 4.537, first on uneven bars scoring 9.875, second on balance beam scoring 9.787, second on floor scoring 9.800. In November 1997, Khorkina caused a scandal by posing for the Russian edition of Playboy, she said, "I changed people's attitudes. It's good to be sexy. My career made. I opened the way. Now I'm famous all over the world". In May 1998, Khorkina competed at the European Championships in Russia, she helped the Russian team finish second and individually she won the all around final with a score of 38.624. In event finals, she placed first on uneven bars scoring 9.900 and first on floor scoring 9.787. In October 1999, Khorkina competed at the World Championships in China.

She helped Russia place second in the team final and individually she placed twelfth in the all around final with a score of 37.611. In event finals, she placed first on uneven bars scoring 9.837 and third on floor scoring 9.787. In May 2000, Khorkina competed at the European Championships in France, she helped the Russian team win the gold medal and individually she won the all around final with a score of 38.749. In event finals, she placed first on uneven bars scoring 9.837 and first on balance beam scoring 9.837. In September, Khorkina competed at the 2000 Summer Olympics in Australia. In qualifications, the Russian team placed first and individually Khorkina placed first in the all around with a score of 39.005. She qualified for the vault, uneven bars, floor event finals. In the team final, Khorkina contributed an all-around score of 38.261 toward the Russian team's second-place finish. In the all around final, Khorkina placed tenth with a score of 37.929. During the final the vault was set five centimeters lower than it should have been, causing many gymnasts, including Khorkina, to fall.

Subsequently, she fell on the uneven bars for unrelated reasons. In the third rotation the vault height was corrected; the gymnasts who had vaulted were invited to vault again, but Khorkina refused, knowing that it would not put her in medal contention. In the event finals, Khorkina gave up her spot in the vault final to teammate, Elena Zamolodchikova, who went on to win the gold medal. Khorkina said, "I thought. I'm glad I could give her that opportunity." She won the uneven bars final with a score of 9.862. Commenting on the all-around final, Khorkina said, "If I didn't get over the disappointment, I wouldn't be Khorkina. I wouldn't be standing here with the gold medal, it still hurts a lot. It was cruel to all the participants. It's quite possible to get killed; the five centimeters could decide the future of a sportsperson. But I was fortunate to have many people to help me get through it. Tomorrow, I will dance for Russia. I will leave what happened on the vault far behind me, like the North Pole."

She won the silver medal in the floor final with a score of 9.812. In October 2001, Khorkina competed at the World Championships in Belgium, she helped the Russian team win the silver medal and individually she won the all around final with a score of 3

Arroyo Seco, Querétaro

Arroyo Seco is a town in Arroyo Seco Municipality located in the far north of the Mexican state of Querétaro. Its territory is part of the Sierra Gorda Biosphere Reserve of Querétaro; the municipality is centered on the small town of Arroyo Seco, established as a military outpost given town status in 1833 under the name of Villa de Guadalupe before changing to its current name. The town gained municipal status in 1931; the area is rural with most people living in communities of under 100 people, with significant Pame communities. It has a traditional economy based on agriculture and forestry but it is one of the poorest in Mexico, with high rates of emigration sending migrant workers to the United States, it is estimated that one in four households in the municipality receives money from family members in this country. The municipality is home to one of five Franciscan mission complexes built under the tenure of Junípero Serra, located in the community of Concá. Arroyo Seco is a small town of about three hundred homes centered on a plaza named after Mariano Escobedo.

The town originated. It became the seat of the municipality of the same name in 1931; the houses are painted in various colors and its streets are quiet. The town is home to all municipal services and has the most developed infrastructure and social services in the area; this includes an auditorium and a library. The Mariano Escobedo plaza has an “oriental” style kiosk surrounded by large trees. On one side the main parish church called; this church was begun in 1904 and was supposed to be much larger than it is, but construction was suspended due to the Mexican Revolution. It has an austere facade and the interior has black pews; the most important yearly event in the municipal seat is the feast of the Virgin of Guadalupe on 12 December. Handcrafts such as saddles, leather goods and wooden barrels for water storage can be found in the town; the municipality is part of the Sierra Gorda region, centered on northern Querétaro state. This region is a branch of the Sierra Madre Oriental, consisting of mountain chains that parallel the Gulf of Mexico.

This land was sea bed 100 million years ago, which formed ancient sedimentary rock limestone, which erodes. This makes the area part of the Huasteca Karst Arroyo Seco is within the Sierra Gorda Biosphere Reserve of Querétaro, established in 1997. Most of the territory is mountainous, with gradients of over 25%. Altitudes in the territory range from 560 to 1340 masl with an average of 980masl; the mountain formations are subdivided into two parts. The first is a corridor along the border with Jalpan, over forty km long and five km wide; this area has some low valleys of only 700 masl. The second area is more rugged with canyons of up to 600 meters deep and peaks which reach over 2000 masl. There are a number of flat areas and valleys which are along the Ayutla and Concá rivers; the principal elevations are Santo Domingo, Cofradía, Soledad and Pitorreal. The terrain is composed of sedimentary rock layers of limestone, which present on the surface with medium or fine grain and sometimes as clay. It, like most of the Sierra Gorda, is on former sea bed from 150 million years ago.

Arroyo Seco and other municipalities of the Sierra Gorda have reported numerous small earthquakes. According to seismologists, these are caused by the movement of water through sedimentary rock. Erosion causes gaps and the gaps settle onto themselves, causing the small quakes. One thing scientists are checking for is to see if any areas stand over underground cavities which may give way; the area's location over the Huasteca Karst and the erosion of limestone has given rise to numerous pit caves. The largest of these in the Sierra Gorda is located in Arroyo Seco, called the Sótano de Barro, located in the Santa María de los Cocos community; the Sótano del Barro is one of the largest cavities of the world by volume, measuring 15 million cubic metres, surpassed only the Sima Mayor de Sarisariñama in Venezuela. In comparison, the Sótano de Las Golondrinas has a volume of only five million meters cubed, its widest diameter measures its average width is 200 meters. It has a total depth of 455 meters with a direct drop of 410 meters.

Its perimeter is surrounded by dense vegetation, a sanctuary for green macaws. It requires a mule ride of about two hours through dense forest to reach; the walls of the pit cave are vertical and covered by vegetation. At the bottom of the cave there is a small forest on a floor, sea bed 100 million years ago, which measures 220 meters long and 100 meters wide. Despite its depth, the bottom of the pit cave receives an abundance of sunlight allowing for the growth of trees and other vegetation, making it an isolated mini forest; the bottom has a number of small caves, with the largest fifty meters long. This pit cave has been classified as the deepest in the world although this has been challenged by those who wish to include those pit caves which are not continuous such as the Stary Swistak in Austria, which has a total depth of 480 meters. Principal river systems include the Santa María, the Ayutla River and the Jalpan River with their tributaries such as the Concá River in the south of the municipality.

The Santa María enters the municipality from San Luis Potosí and flows along a 400 meter deep canyon until it merges with the Ayutla River. This river flows northeast, forming another canyon merges with the Jalpan River. There are about 100 accessible sources of water in the municipality with most located in the communities of Salitr

Horrible Science

Horrible Science is a similar series of books to Horrible Histories, written by Nick Arnold, illustrated by Tony de Saulles and published in the UK and India by Scholastic. They are designed to get children interested in science by concentrating on the trivial, gory, or unpleasant; the books are in circulation in 24 countries, over 4 million books have been sold in the UK alone. Nick Arnold released a paper entitled "Teaching Science the Horrible Way", in which he demonstrates the reasons why the Horrible Science series has a positive contribution to learning. According to Arnold, Horrible Science books are based on everyday topics and key areas of the curriculum; the range of approaches used in Horrible Science books are intended to emphasise the drama and excitement and wonder of science. Science words and concepts are introduced often using humour or fact files. Although mathematics is not needed at the level of science covered in the books, some activities require calculators; the books contain experiments under the heading Dare you discover...

The experiments do not elaborate equipment. Several of the books end with thoughts on. On his website, Nick Arnold has downloadable experiments for teachers to use in the classroom as an aid to his books. Before writing the series, Nick Arnold was at the University of North London working on an educational project, he explained to The Birmingham Post: "It was a lucky break or a well-placed letter – whichever you want to believe – Because I wrote this cheeky letter to the publishers Scholastic saying that if they were looking for someone to write a horrible science book I was the one. And would you believe they let me write a science book and put lots of horrible bits in it – and it was hugely successful”. During the mid-2010s, Horrible Science decided to have a book makeover, altering the covers of some of their old books, all of the new books being published to have a new, more colorful background and updated information. A Horrible Science theatre show produced by the Birmingham Stage Company – which brought Horrible Histories to the stage – was created in 2013.

Nick Arnold explained his approach towards writing the series in an interview with The Birmingham Post: "My approach to a subject is to vastly over-research it. I have become quite good at science by writing these books so have got quite a lot of knowledge but I like finding out more information. If I over-research I don’t just have all the facts I need, I have a lot more – and that means I can choose what I want to include; the thing about a Horrible Science book is that it is all about imagination. The more you know the more you want to know and the more you want to develop that." The response towards the series has been positive. Some reviews of the series website included a The Independent review that Really Rotten Experiments is "Perfect for keeping the kids occupied on a rainy day, this is full of useful tips...and fun, naughty experiments". Another review by the Evening Express said that the book Horrible Science: Painful Poison is "With fantastic fact files, quirky quizzes, humorous cartoons and easy-to-understand text, it makes science pretty horrible, but great fun".

Books For Keeps said of the book Deadly Diseases: "Gruesome gut churning contents, you need a strong stomach to tackle this, before eating". The Scotsman commented on the series as a whole, "Nick Arnold has a reputation as quite a showman and his Horrible Science series provides him with plenty of opportunity for stunts. Children emerge wide-eyed and inspired". A review at described the series as "These are so much better than some of the dry textbooks that I used to have to read when I was in school... I'm saying that books like this are great for students because they show students that science is interesting and amazing!". A review by Roberta of the Growing with Science blog said of the book Chemical Chaos: "It is every bit as humorous and as comprehensive as the history series was", she adds that the " go a long way to fill that gap [between middle and high school students". As said of Evil Inventions in a review by Jennifer Cameron-Smith at: "This is a delightful book and would make a wonderful present for any budding young scientist as well as a worthwhile addition to a school library.

Making science fun can sometimes be a challenge, but books such as this assist." There has been a negative response to Issue 6 - Hidden Horrors in the Home in the magazine adaption of the book series. The article named "Loony Lab" in this Horrible Science Collection had a section called "Grow your own manky microbes". A complainant, a biology teacher and parent, described it as "irresponsible in the extreme". A plastic petri dish and sachet of agar powder are provided as a "free gifts", children are encouraged to sample areas which may harbour disease-causing organisms, such as a toilet handle, a dog's ear, or a "bogey". Under certain circumstances, contact with these substances is life-threatening; the complainant added. In school, under supervision of trained staff, we would not be allowed to do much of what the article suggests, namely for health and safety reasons. How can they be sure that every child will follow the meagre and woefully inadequate safety advice given?" The Horrible Science series has received the following awards: The ZSL Thomson Reuters Record Award for Communicating Science awarded to Nick Arnold and Tony De Saulles for Wasted World.

Arnold said "Fo

Penugonda mandal

Penugonda mandal is one of the 46 mandals in West Godavari district of the Indian state of Andhra Pradesh. The headquarters are located at Penugonda town; the mandal is bordered by Godavari river to north, Achanta mandal to the east, Penumantra mandal and Iragavaram mandal to the south and Peravali mandal to the west. As of 2011 census, the mandal had a population of 69,317 in 19,124 Households; the total population constitute, 34,837 males and 34,480 females with a sex ratio of 970 females per 1000 males. 6,535 children are in the age group of 0–6 years, of which 3,334 are boys and 3,201 are girls with a sex ratio of 960. The average literacy rate stands at 77.67% with 48,763 literates of which 25,728 are males and 23,035 are females. Majority are Schedule Caste with a population of 14,423 whereas Schedule Tribe had a population of 570; as per the report published by Census India in 2011, 31,975 people were engaged in work activities out of the total population of Penugonda mandal which includes 21,847 males and 10,128 females.

According to census survey report 2011, 27,027 workers describe their work as main work, 2,238 as Cultivators, 18,373 person work as Agricultural labourers. 429 are working in Household industry and 5,987 are involved in other works. Of them 4,948 are Marginal workers. Penugonda mandal is administered under Achanta of Narsapuram and one of the twelve mandals that falls under Narasapuram revenue division; as of 2011 census, the mandal has 14 settlements. Penugonda is munamarru is the smallest village in terms of population; the settlements in the mandal are listed below: The mandal plays a major role in education for the rural students of the nearby villages. The primary and secondary school education is imparted by government and private schools, under the School Education Department of the state; as per the school information report for the academic year 2015–16, the mandal has more than 9,501 students enrolled in over 90 schools. List of mandals in Andhra Pradesh Eluru