about the physical effect self maintained thermal homeostasis Endotherm In thermodynamics , the word endothermic within heating describes a process or reaction in which the system absorbs energy from the surroundings in the form of heat . Its etymology stems from the Greek prefix endo , meaning inside and the Greek suffix ther , meaning heat . The opposite of an endothermic process is an exothermic process, one that releases energy in the form of heat. The term endothermic was coined by Marcellin Berthelot 25 October 1827 18 March 1907 . The concept is frequently applied in physical sciences to, for example, chemical reactions , where thermal energy heat is converted to chemical bond energy . Overview Endothermic , refers to a chemical reaction in which a system receives heat from the surroundings as opposed to endergonic , which receives energy from the surroundings Q 0 When this occurs at constant pressure H 0 and constant volume U 0 If the surroundings do not supply heat e.g., when the system is Adiabatic process adiabatic , an endothermic transformation leads to a decrease in the temperature of the cycle. ref cite book last Perrot first Pierre title A to Z of Thermodynamics publisher Oxford University Press year 1998 isbn 0 19 856552 6 ref Endothermic processes Some examples of endothermic processes are ref http antoine.frostburg.edu chem senese 101 thermo faq exothermic endothermic examples.shtml Exothermic Endothermic examples ref A chemical cold pack consisting primarily of ammonium nitrate and water . Evaporation of water Photosynthesis Implications for chemical reactions Chemical endothermic reactions need heat to be performed. In a thermochemical reaction that is endothermic, the heat is placed on the reactants side heat is necessary for and absorbed during the reaction . See also Exothermic Exergonic Exergonic reaction References reflist External links http www.ilpi.com msds ref exothermic.html Endothermic Definition MSDS Hyper Glossary http tobias.kieser ... more details
Endothermic gas is the gaseous product of incomplete combustion in a controlled environment with a composition of hydrogen gas H sub 2 sub , nitrogen gas N sub 2 sub , and carbon monoxide CO . Hydrogen and carbon monoxide are reducing agents, so they shield surfaces from oxidation . physical chemistry stub Category Gases ... more details
For Exergonic and Endergonic reactions , see the separate articles Endergonic reaction Exergonic reaction See also Exergonic Endergonic Exothermic Endothermic Disambig ... more details
endothermic reactions occur, energy is absorbed to place an electron in a higher energy state, such that the electron ... within solution is absorbed by the endothermic reaction and therefore is a loss of heat. This is the physical understanding of exothermic and endothermic reactions within solution. Therefore in an exothermic ... endothermic examples.shtml Exothermic Endothermic examples ref Condensation of rain from water vapor ... reactions are generally more spontaneous than their counterparts, endothermic reaction s. In a thermochemical ... Endergonic Endergonic reaction Exergonic Exergonic reaction Endothermic reaction External links ... more details
The enthalpy of solution , enthalpy of dissolution , or heat of solution is the enthalpy change associated with the dissolution of a substance in a solvent at constant pressure resulting in infinite dilution. The enthalpy of solution is one of the three dimensions of solubility analysis. It is most often expressed in Joule kJ mole unit mol at constant temperature. Just as the energy of forming a chemical bond is the difference between electron affinity and ionization energy , the heat of solution of a substance is defined as the sum of the energy absorbed, or endothermic energy, expressed in positive values and unit kJ mol, and energy released, or exothermic energy negative value . Because heating decreases the solubility of a gas, dissolution of gases is exothermic. Consequently, as a gas continues to dissolve in a liquid solvent, temperature will decrease, while the solution continues to release energy. This is an effect of the increase in heat or of the energy required to attract solute and solvent molecules&mdash in other words, this energy outweighs the energy required to separate solvent molecules. When the gas is completely dissolved this is purely theoretical as no substance can infinitely dissolve , the heat of solution will be at its maximum. Dissolution can be viewed as occurring in three steps Breaking solute solute attractions endothermic , see for instance lattice energy in salts. Breaking solvent solvent attractions endothermic , for instance that of hydrogen bonding Forming solvent solute attractions exothermic , in solvation . The value of the overall enthalpy change is the sum of the individual enthalpy changes of each of these steps. For example, dissolving ammonium nitrate in water decreases the temperature of the solution. Solvation does not compensate energy spent in breaking down the crystal lattice, while adding potassium hydroxide will increase it. Solutions with negative enthalpy changes of solution form stronger bonds and have lower vapor ... more details
Unreferenced date May 2009 Merge to anabolism date September 2010 Endergonic from the suffix endo , derived for the Greek word endon , within and the English suffix ergonic, derived from the Greek word ergon , work thermodynamics work means absorbing energy in the form of work. Endergonic reactions are not spontaneous. By thermodynamic standards, work, a form of energy , is defined as moving from the wikt surroundings surroundings the external region to the system the internal region . Thus, an endergonic process, as contrasted with an exergonic process, is one wherein the system absorbs energy from the surroundings. As a result, during an endergonic process, energy is put into the system. If the transformation occurs at constant pressure and temperature, G 0 . An endergonic reaction is a chemical reaction that absorbs energy in the form of work. A good example of an endergonic reaction is photosynthesis . Also, in metabolism , an endergonic reaction is anabolic , meaning, the break down of energy. In metabolism, catabolic and anabolic are coupled by Adenosine triphosphate ATP . An endergonic reaction is, in essence, the opposite of an exergonic reaction. Since endergonic reactions require energy, they form molecular bonds, which decreases entropy . These bonds are energy carriers, so the formation of these bonds requires some energy input. Cold packs, which become cold after mixing two liquids, exploit this property. In fact, a common reaction that is clearly endergonic is the mixing of ammonium chloride and water. There is a net drop in temperature of the reaction as a result of the solvation of ammonium ion s. See also col begin col break Exergonic Exergonic reaction Exothermic Endothermic col break Exothermic reaction Endothermic reaction Warm blooded Endotherm Warm blooded Exotherm col end Category Thermodynamics Category Chemical thermodynamics ar hu Endergonikus reakci nl Endergoon ... more details
One source date May 2009 Wiktionary exergonic Merge to catabolism date September 2010 Exergonic from the suffix exo , derived for the Greek word ex , outside and the suffix ergonic, derived from the Greek word ergon , work thermodynamics work means releasing energy in the form of work . By thermodynamic standards, work, a form of energy , is defined as moving from the system the internal region to the surroundings the external region . Thus, an exergonic process, as contrasted with an endergonic process, is one that releases energy from the system, of which it is a part, to the surroundings. ref GoldBookRef title exergonic exoergic reaction file E02262 ref As a result, during an exergonic process, energy is released out of the system. If the transformation occurs at constant pressure and temperature, G 0. When Gibbs free energy is less than 0, the reaction is exergonic releases energy . All physical and chemical systems in the universe follow the second law of thermodynamics and proceed in a downhill, i.e., exergonic , direction. Thus, left to itself, any physical or chemical system will proceed, according to the second law of thermodynamics , in a direction that tends to lower the thermodynamic free energy free energy of the system, and thus to expend energy in the form of work. These reactions occur spontaneously. See also col begin col break Endergonic Endergonic reaction Exothermic Endothermic Exergonic reaction col break Exothermic reaction Endothermic reaction Warm blooded Endotherm Warm blooded Exotherm col end References Reflist Category Thermodynamics Category Chemical thermodynamics de Exergone und endergone Reaktion fr R action exergonique hu Exergonikus reakci nl Exergoon pt Exerg nica ... more details
The BMA process ref The name is abbreviated from B laus ure hydrogen cyanide from M ethan methane and A mmoniak ammonia in German. ref or Degussa process is a chemical process developed by Degussa ref http www.patentstorm.us patents 5928984 description.html patent literature ref for the production of hydrogen cyanide from methane and ammonia in presence of a platinum Catalysis catalyst . Hydrogen cyanide is used in the chemical industry for the production of intermediate chemicals like acrylonitrile, methyl methacrylate, and adiponitrile. The reaction equation is analog to the Steam reforming steam methane reforming SMR reaction of methane and water CH sub 4 sub NH sub 3 sub &rarr HCN 3 H sub 2 sub , &Delta H sub R sub 251 kJ mol The reaction is extremely endothermic . The reactants react in a Platinum covered pipe at temperatures around 1400 C. The reaction mixture contains around 23 Vol. HCN and 72 Vol. H sub 2 sub as well as minor quantities of ammonia, nitrogen, and unreacted methane. ref cite journal title Die technische Synthese von Cyanwasserstoff aus Methan und Ammoniak ohne Zusatz von Sauerstoff author F. Endter journal Chemie Ingenieur Technik year 1958 volume 30 issue 5 pages 281 376 doi 10.1002 cite.330300506 ref The gaseous mixture is introduced in a scrubber and treated with an ammonia solution in order to separate the acidic HCN from the other gaseous components H sub 2 sub , CH sub 4 sub , and N sub 2 sub . In a second step the HCN is released by acidification of the solution, followed by a final distillation of the hydrogen cyanide. Because of the highly endothermic reaction, the BMA process is of lower importance for the production of HCN compared to the Andrussow oxidation . References references External links http www.methacrylates.de methacrylates MCMSbase Templates WWWTemplate.aspx?NRMODE Published&NRNODEGUID 7b855AEA74 FFCC 4FE6 991E FE45567D5FC9 7d&NRORIGINALURL 2fmethacrylates 2fen 2fproducts 2fmonomers 2flicenses 2fhcntechnology 2f&NRCACHE ... more details
An exergonic reaction is a chemical reaction where the change in the Gibbs free energy is negative, ref IUPAC Gold Book definition http www.iupac.org goldbook E02262.pdf search Exergonic 20reaction exergonic exoergic reaction ref indicating a spontaneous reaction . Symbolically, the release of Gibbs free energy, G , in an exergonic reaction is denoted as math Delta G G rm products G rm reactants 0. , math Although exergonic reactions are said to occur spontaneously , this does not imply that the reaction will take place at an observable Reaction rate rate . For instance, the Catalysis Background disproportionation of hydrogen peroxide is very slow in the absence of a suitable catalyst. It has been suggested that eager would be a more intuitive term in this context. ref cite journal doi 10.1021 ed061p710 last Hamori first Eugene coauthors James E. Muldrey date 1984 title Use of the world eager instead of spontaneous for the description of exergonic reactions journal Journal of Chemical Education volume 61 issue 8 pages 710 ref More generally, the terms exergonic and endergonic relate to the Gibbs free energy change in any process, not just chemical reactions. An example of an exergonic reaction is cellular respiration. The terms exothermic and endothermic reactions relate to the enthalpy change of a process. See also Endergonic reaction A References reflist Category thermochemistry de Exergon pl Reakcja egzoenergetyczna ... more details
For the biological process, see decomposition . Thermal decomposition , or thermolysis , is a chemical decomposition caused by heat. The reaction is usually endothermic as heat is required to break chemical bond s in the compound undergoing decomposition. The decomposition temperature of a substance is the temperature at which the substance chemically decomposes. If decomposition is sufficiently exothermic , a positive feedback loop is created producing thermal runaway and possibly an explosion. Examples Calcium carbonate decomposes into calcium oxide and carbon dioxide when heated CaCO sub 3 sub CaO CO sub 2 sub Water , when heated to well over 2000 C, decomposes to its constituent elements 2 H sub 2 sub O 2 H sub 2 sub O sub 2 sub The compound with the highest known decomposition temperature is carbon monoxide at 3870 C 7000 F . Citation needed date August 2010 . See also Ellingham diagram Thermal depolymerization Chemical thermodynamics References Reflist DEFAULTSORT Thermal Decomposition Category Chemical reactions ar de Thermolyse es Term lisis fr Thermolyse chimie it Termolisi nl Thermolyse ja pl Termoliza pt Decomposi o t rmica sv Termisk nedbrytning reaction stub thermodynamics stub ... more details
thermic may refer to one or more of these topics related to heat a past synonym for thermal disambiguation thermal also, thermics was a synonym for thermodynamics the thermic effect of food TEF the thermic reaction of skin , a topic of 19th century hydrotherapy http books.google.com.au books?id nZDveDNq1VwC , but the phrase is also used more recently in other contexts PMID 14876412 thermic reaction may refer to a triggered change in Core temperature body temperature http ajplegacy.physiology.org cgi pdf extract 76 2 284 thermic reaction or thermic process can refer to a chemical reaction that may turn out to be exothermic or endothermic the suffix thermic , as in the following list of thermic inorganic chemistry inorganic reactions involving redox chemical reduction . Highly thermic reactions are those requiring or producing a large amount of heat. Aluminothermic reaction , the thermite reaction being a prominent example Calciothermic reaction Carbothermic reaction Silicothermic reaction thermal lance thermic lance thermic component , thermic composition , thermic effect or thermic reaction may refer to a near explosive property http www.uspto.gov go classification uspc149 defs149.htm thermic reaction or thermic binding can refer to biochemical processes PMID 3542032 disambig ... more details
An instant cold pack is a device which consists of two bags, one containing water which is inside a second bag containing ammonium nitrate . When the inner bag is broken by squeezing the package, the ammonium nitrate is allowed to dissolve in the water in an endothermic reaction. This reaction absorbs heat from the surroundings, quickly lowering the pack s temperature. ref cite web publisher Howstuffworks.com author Marshall Brain title Cold Packs work How Refrigerators Work url http home.howstuffworks.com refrigerator7.htm ref Instant cold packs are a convenient direct replacement for crushed ice used as first aid on sports injury sport injuries . It is also important not to refrigerate before activation. This may result in frostbite if used for prolonged periods of time. Due to safety reasons, instant cold packs have recently been developed without ammonium nitrate. ref InstaKool An Ammonium Nitrate Free Instant Cold Pack Ammonium Nitrate Free Cold Pack http www.nortechlabs.com instakool instant cold pack.html ref Notes Reflist DEFAULTSORT Instant Cold Pack Category Cooling technology ... more details
of ammonia production Key points The concept and its opposite number endothermic relate to the enthalpy ... Exergonic Endergonic reaction Exergonic reaction Exothermic Endothermic reaction Warm blooded ... more details
agent. Cases of the exothermic and endothermic reactions of the transporting agent Transport ..., when the reaction of the solid and the transport agent is endothermic, the solid is transported ... chloride HCl eqm Iron III chloride Fe sub 2 sub Cl sub 6 sub 3 H sub 2 sub O H sub rxn sub 0 endothermic ... more details
Refimprove date February 2007 In India there are 410 species of mammal s 8.86 of the world s mammals , which are spread over 186 genus genera , 45 family biology families and 13 order biology order s out of which nearly 89 species are listed as threatened in the International Union for Conservation of Nature and Natural Resources IUCN Red List of Threatened Animals IUCN 2006 . This includes two species that are locally extinct from India viz. Acinonyx jubatus and Rhinoceros sondaicus . The mammals are the Class biology class of vertebrate animals characterized by the presence of mammary gland s, which in female s produce milk for the nourishment of young the presence of hair or fur specialized tooth teeth the presence of a neocortex region in the brain and endothermic or warm blooded bodies. The brain regulates endothermic and circulatory system , including a four chambered heart . Mammals encompass some 5,500 species including Human s , distributed in about 1,200 genera, 152 families and up to 46 orders, though this varies with the classification scheme. Endangered Mammals Asiatic Golden Cat Felis temmincki Asiatic Lion Panthera leo persica Asiatic Cheetah Acinonyx jubatus venaticus thought to be Extinct now in India Indian Wild Ass or Khur Equus hemionus khur Dhole Asiatic Wild Dog Dhole Cuon alpinus Asiatic Black Bear Selenarctos thibetanus Banteng Bos javanicus Bengal Fox Vulpes bengalensis Eld s Deer Brow antlered Deer Cervus eldi eldi Brown Bear Ursus arctos Jerdon s Palm Civet Paradoxurus jerdoni Amblonyx cinereus Clawless Otter Amblonyx cinereus Clouded Leopard Neofelis nebulosa European Otter Common Otter Lutralutra wild Cat Felis lybica ornata Dugong Seacow Dugong dugon Ganges River Dolphin Platanista gangetica Gaur Bos gaurus Golden Langur Trachypithecus geei Goral Nemorhaedus goral Indian Rhinoceros Rhinoceros unicornis Grey Wolf Indian Wolf Canis lupus Himalayan W toothed Shrew Crocidura attenuate Fact date February 2007 Martes flavigula Himalayan Marte ... more details
Comment WHAT S IMG 0030.JPG ??? It seems to be a redirect to File Alvaro Uribe in INNOVA Awards 2006.jpg . Code for generating a thumbnail on the right Image FILENAME.EXT thumb right alt Alt text for visually impaired readers... Caption... ...END of comment. ThermaHelm , invented by neuroprotective specialist Jullian Joshua Preston Powers in 2005, is an impact activated, brain cooling Motorcycle helmet motorcycle crash helmet being developed at the University of Sussex Sussex Innovation Centre Innovation Centre SInC . ref name MO 2010 01 18 cite web url http www.dailymail.co.uk sciencetech article 1242886 Brain cooling motorcycle helmet save thousands lives.html title Brain cooling motorcycle helmet could save thousands of lives author Daily Mail Reporter date 18th January 2010 work Science&Tech publisher Mail Online location accessdate 22 October 2010 ref ref Preston Powers, Jullian Joshua. http www.wipo.int patentscope search en detail.jsf?docId WO2009095690&recNum 3&docAn GB2009000273&maxRec 22&office &prevFilter &sortOption Pub Date Desc&queryString FP 3A 28BRAIN COOLING DEVICE 29&tab PCT Biblio. Data BRAIN COOLING DEVICE , World Publication No. WO 2009 095690, Publication Date 06.08.2009, International Application No. PCT GB2009 000273. ref Ammonium nitrate and water , stored in separate areas of the helmet s liner, combine when trigger activated by an impact to create an Endothermic endothermic reaction with the intention of preventing terminal brain swelling, ref name MO 2010 01 18 and the aim of reducing the immediate and long term effects of traumatic brain injury TBI , a List of causes of death by rate major cause of death and disability worldwide . ref name SInC 330 cite web url http www.sinc.co.uk news ?p 330 title Chemical brain cooling ThermaHelm crash helmet praised as a life saver by Speedway legend Martin Dugard date 24 December 2009 work News & Media publisher SInC format XHTML accessdate 22 October 2010 ref When activated by sudden impact, the hel ... more details
About biological thermoregulation chemical reactions Endothermic An endotherm is an organism that produces heat through internal means such as muscle shivering or increasing their metabolism Greek endon within , therm heat . The opposite of endothermy is ectothermy . Mechanisms Generating and conserving heat File Homeothermy poikilothermy.png thumb right Sustained energy output of a warm blooded mammals and a cold blooded reptile animal as a function of core temperature Many endotherms have a larger number of mitochondria per cell biology cell , which enables them to generate heat by increasing the rate at which they metabolize fat s and sugar s. These animals require a much greater quantity of food than ectothermic animals to sustain their higher metabolism. In many endothermic animals, a controlled state of hypothermia called hibernation , or torpor conserves energy by lowering the body temperature. Many birds and small mammals e.g. tenrec s body temperature drops during daily inactivity, such as at night for diurnality diurnal animals or during the day for nocturnality nocturnal animals thus reducing the energy cost of maintaining body temperature. Human metabolism also slows down slightly during sleep. The resting human body generates about two thirds of its heat through metabolism inside internal organs in the thorax and abdomen, as well as in the brain. The brain generates about 16 of the total heat produced by the body. ref http users.rcn.com jkimball.ma.ultranet BiologyPages H HeatTransport.html ref Heat loss is a major threat to smaller creatures as they have a larger ratio of surface area to volume . Most small warm blooded animals have insulation in the form of fur or feather s. Aquatic, warm blooded animals, such as pinniped seals generally have deep layers ... system. Advantages and disadvantages of an endothermic metabolism The overall rate of an animal ... metabolic activity for as long as endotherms. Endothermic homeothermic animals can be optimally ... more details
Taxobox name Hadrocodium fossil range Early Jurassic regnum Animal ia image image width 250px image caption Hadrocodium skull phylum Chordata subphylum Vertebrata unranked classis Amniota classis Synapsida unranked ordo Mammaliaformes genus Hadrocodium Hadrocodium wui is an extinct Basal phylogenetics basal mammal species that lived during the Lower Jurassic approx. 195 million years ago, during the Sinemurian stage in what is now the Yunnan province of China . Hadrocodium was a mere 3.2 cm 1.35 in in length about 2 grams , and is one of the smallest mammals of either the Mesozoic or Cenozoic eras. Hadrocodium is the earliest known example of several features distinctive to mammals, ref http www.palaeos.com Vertebrates Units Unit420 420.300.html Symmetrodonta Palaeos ref including mammal like mandible and middle ear structures and a relatively large brain cavity. ref http archives.cnn.com 2001 TECH science 05 24 tiny.ancestor index.html Tiny creature may be ancestor of all mammals CNN ref The discovery of Hadrocodium suggests that the origination of these distinctive mammaliaform features was much older 45 million years older than previously thought. Whether Hadrocodium was Warm blooded endothermic or Poikilotherm cold blooded has not been settled, although its apparent Nocturnal animal nocturnal features would seem to place it in the endotherm group. References reflist Bibliography cite journal author Z. X. Luo, A. W. Crompton and A. L. Sun year 2001 title A New Mammaliaform from the Early Jurassic and Evolution of Mammalian Characteristics journal Science journal Science volume 292 pages 1535&ndash 1540 url http www.carnegiemnh.org vp media Luo Hadrocodium .pdf doi 10.1126 science.1058476 pmid 11375489 issue 5521 Category Mammaliaformes Category Jurassic mammals Category Jurassic extinctions Category Prehistoric mammals of Asia paleo mammal stub ca Hadrocodium wui de Hadrocodium es Hadrocodium fr Hadrocodium it Hadrocodium wui nl Hadrocodium pl Hadr ... more details
DISPLAYTITLE Q value nuclear science Other uses Q value disambiguation Q value In nuclear physics and nuclear chemistry chemistry , the Q value for a nuclear reaction reaction is the amount of energy released by that reaction math Q E left text Reactants right E left text Products right , math A reaction with a positive Q value is exothermic has a net release of energy , while a reaction with a negative Q value is endothermic requires a net energy input . ref name Krane cite book author K.S. Krane year 1988 title Introductory Nuclear Physics page 381 publisher John Wiley & Sons isbn 047180553X ref Q values are also featured in particle physics . For example in Sargent s rule , which states that the reaction rate of weak interactions is proportional to Q sup 5 sup . The Q value is the kinetic energy released in the decay of the particle at rest. For example, for neutron decay ref name Martin cite book author B.R. Martin and G. Shaw year 2007 title Particle Physics page 34 publisher John Wiley & Sons isbn 0 471 97285 1 ref math Q m text n m text p m mathrm overline nu m text e c 2 math where m sub n sub is the mass of the neutron , m sub p sub is the mass of the proton , m sub overline &nu sub is the mass of the electron antineutrino and m sub e sub is the mass of the electron . See also Fusion energy gain factor Notes and references reflist External links http www nds.iaea.org queryensdf Nuclear Structure and Decay Data IAEA with query on decays Q values Category Nuclear physics chem stub ... more details
About the music album the year 8th millennium BC unreferenced date February 2011 Infobox album See Wikipedia WikiProject Albums Name 8000 B.C. Type Studio album Artist Otto von Schirach Cover Ovs 8000bc.jpg Released May 15, 2001 Genre Intelligent Dance Music IDM Length 63 03 Label Schematic Records Schematic Reviews Allmusic Rating 4 5 Allmusic class album id r532413 pure url yes link Pitchfork Media 5.2 10 http web.archive.org web 20011126215542 pitchforkmedia.com record reviews v vonschirach otto 8000 bc.shtml link Last album This album 8000 B.C. br 2001 Next album Escalo Frio br 2001 8000 B.C. is an Intelligent Dance Music IDM LP by Otto von Schirach , released in 2001 on Schematic Records. Track listing Tracklist title1 25 46 x 80 12 length1 3 16 title2 Time Traveling Lives length2 4 41 title3 Tympanic Calcoolus length3 4 43 title4 Lunatic Nitrates length4 4 59 title5 C21 H39 N7 O12 length5 4 05 title6 Triangle Exit length6 4 27 title7 Ecleptosze Chemiz Tri length7 3 25 title8 Endothermic Cavewalker length8 5 09 title9 Schematropolis Mirage length9 3 46 title10 No Wood length10 2 33 title11 Aquantumzation Below Zero length11 4 35 title12 Elastic Paranormalites length12 6 19 title13 Insectdezyde Juice length13 6 41 title14 Smelly Mustard length14 4 24 title15 Purple Pickle Eater note15 vinyl only length15 3 27 Notes The vinyl release of the album omitted the track No Wood , but included a bonus 7 inch with an exclusive track entitled Purple Pickle Eater . Category Otto von Schirach albums Category 2001 albums 2000s electronic album stub ... more details
Orphan date February 2009 unreferenced date June 2009 Direct injection expanded foam molding also known as injection molded foam is a foam manufacturing process that creates soft foam products direct from compound into a final product. This process eliminates the steps required for die cutting and compression molding , as it manufactures the foam and the product simultaneously. The base resin used in a complex formula, is an ethylene based polyolefin elastomer like polyethylene and Ethylene Vinyl Acetate EVA . Foam manufactured with these resins has many physical benefits. Unlike a sponge, foams from this process are closed cell, meaning it s waterproof and resists mold, mildew and bacteria from entering the material. It is also cross linked, which means that the cells are connected in a way that makes the foam strong and durable with high tear and tensile strength. All polyolefin elastomers are also resistant to most chemicals, which allow the products to not only be used in a chemical environment, but also very cleanable with most household cleaners. The process itself is known to be very interesting, because the injected compound is not foam, until an endothermic reaction in a hot mold activates the blowing agents, resulting in an expanded foam part. This requires the mold cavity size to be smaller than the final part. The actual known expansion is created within the formula, so that when the part self ejects from the mold at the end of the cycle, it grows to the required part size. The cavity for a tire is considerably smaller than the final tire size. This process is valuable for any foam product that needs to have lots of detail. It needs to be very durable. External links http www.macho.com upimages tire1.jpg Cavity for a tire DEFAULTSORT Direct Injection Expanded Foam Molding Category Injection molding ... more details
Image Zinc zinc oxide thermochemical cycle.jpg 350 px right The Zn ZnO cycle The zinc zinc oxide cycle or Zn ZnO cycle is a two step thermochemical cycle based on zinc and zinc oxide ref http www.solarpaces.org Tasks Task2 SHP.HTM Solar Hydrogen Production from a ZnO Zn Thermo chemical Cycle ref for hydrogen production ref http www.hydrogen.energy.gov pdfs review06 pd 10 weimer.pdf Project PD10 ref with a typical efficiency around 40 . ref http www.switt.ch files technologien Solar 20Hydrogen 20Production 04 014.pdf Novel Method for solar hydrogen generation ref Process description The thermochemical two step water splitting process uses redox systems ref http solar.web.psi.ch data research zno roca Solar thermal ZnO decomposition ref Dissociation chemistry Dissociation Zinc oxide ZnO Zinc Zn 1 2 O sub 2 sub Hydrolysis Zinc Zn Water molecule H sub 2 sub O Zinc oxide ZnO Hydrogen H sub 2 sub For the first endothermic step concentrating solar power is used in which zinc oxide is Thermal decomposition thermally dissociated at C to F 1900 into zinc and oxygen. In the second non solar exothermic step zinc reacts at C to F 427 with water and produces hydrogen and zinc oxide. The temperature level is realized by using a solar power tower and a set of heliostat s to collect the solar thermal energy . See also Cerium IV oxide cerium III oxide cycle Copper chlorine cycle Hydrosol 2 Hybrid sulfur cycle Iron oxide cycle Sulfur iodine cycle References reflist External links http www.ltnt.ethz.ch people bburg MRS05 Burg.pdf H2 formation by zinc hydrolysis in a hot wall aerosol flow reactor Category Chemical reactions Category Hydrogen production de Solzinc Verfahren nl Zink zinkoxidecyclus ... more details
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