Technical date April 2010 Test sample values align right The anion gap is the difference in the measured ... the cause of metabolic acidosis . If the gap is greater than normal, then high anion gap metabolic acidosis is diagnosed. The term anion gap usually implies Blood serum serum anion gap , but the urine anion gap is also a clinically useful measure. ref name urlUrine Anion Gap Acid Base Tutorial ... Urine Anion Gap.html title Urine Anion Gap Acid Base Tutorial, University of Connecticut Health Center work accessdate 2008 11 14 ref ref name urlUrine anion and osmolal gaps in metabolic acidosis ... anion and osmolal gaps in metabolic acidosis format work accessdate 2008 11 14 ref ref name pmid10360635 ... anion and osmolar gaps journal The Journal of Laboratory and Clinical Medicine volume 133 issue 6 pages ... Citations missing date May 2009 Anion gap is an artificial and calculated measure that is representative ... sup sup K are used when calculating the anion gap. In normal health there are more measurable cations compared to measurable anions in the serum therefore, the anion gap is usually positive. Because we know that plasma is electro neutral we can conclude that the anion gap calculation represents the concentration of unmeasured anions. The anion gap varies in response to changes in the concentrations of the above mentioned serum components that contribute to the acid base balance. Calculating the anion ... which give a normal anion gap as 11 mEq L. Therefore according to the new classification system a high anion gap is anything above 11 mEq L and a normal anion gap is often defined as being within ... Winter SD, Pearson JR, Gabow PA, Schultz AL, Lepoff RB title The fall of the serum anion gap journal ... 10.2215 CJN.03020906 noedit ref In the past, methods for the measurement of the anion gap consisted ... bodyfluids theanion.htm title The Anion Gap accessdate 2008 10 04 ref ref Cite web url http fitsweb.uchc.edu student selectives TimurGraham Anion Gap.html title Anion Gap Acid Base ... more details
Organic anions are chemically heterogeneous substances possessing a carbon backbone and a net negative charge. ref name pmid10954321 cite journal author Sekine T, Cha SH, Endou H title The multispecific organic anion transporter OAT family journal Pflugers Arch. volume 440 issue 3 pages 337 50 year 2000 month July pmid 10954321 doi url http link.springer.de link service journals 00424 bibs 0440003 04400337.htm issn ref Organic anions are conjugate base s of organic acid s. The following table lists some of the organic anions and their conjugate acids which are substrates of the Organic anion transporting polypeptide Organic anion transporter OAT family organic acid transporter OAT family of transmembrane proteins. class wikitable sortable border 1 Organic Anions br Conjugate Organic Acids br acidic proton is shown in red Aminohippuric acid p aminohippurate PAH image aminohippuric acid2.png left thumb 250px Aminohippuric acid cyclic nucleotides image Cyclic adenosine monophosphate 2D skeletal4.png left thumb 250px Cyclic adenosine monophosphate cAMP image CGMP2.svg right thumb 250px br br Cyclic guanosine monophosphate cGMP prostaglandins dicarboxylates alpha ketoglutarate References reflist Category Solute carrier family Category Transmembrane proteins Category Transmembrane transporters Category Transport proteins ... more details
The cyclooctatetraenide dianion is an aromatic organic chemistry organic anion with the structure C sub 8 sub H sub 8 sub sup 2 sup . It is planar and aromatic, like the cyclopentadienide anion, and, like cyclopentadienide, easily forms compounds with metals. Image Cyclooctatetraenide 3D ball.png thumb right 200px Ball and stick model of COT sup 2 sup Compounds The salt potassium cyclooctatetraenide is easily formed by the reaction of cyclooctatetraene with potassium metal. It has the structure K sub 2 sub C sub 8 sub H sub 8 sub , or K sub 2 sub COT . Cyclooctatetraenic acid is a hypothetical acid with the structure H sub 2 sub C sub 8 sub H sub 8 sub , or H sub 2 sub COT . Image Uranocene 3D vdW.png thumb right Uranocene , a sandwich compound containing two COT sup 2 sup rings. Several sandwich compound s involving the cyclooctatetraenide anion are known, the most notable of which are the actinocene s, such as uranocene , U C sub 8 sub H sub 8 sub sub 2 sub or U COT sub 2 sub , thorocene , Th C sub 8 sub H sub 8 sub sub 2 sub or Th COT sub 2 sub , and plutonocene , Pu C sub 8 sub H sub 8 sub sub 2 sub ferricene not to be confused with ferrocene , Fe C sub 8 sub H sub 8 sub sub 2 sub , is also known. Since the actinides can also exist in the III oxidation stade, they can also exist in the form where A is any actinide AC sub 5 sub H sub 5 sub C sub 8 sub H sub 8 sub , or A Cp COT , as the cyclopentadienide cyclooctatetraenide. An example of this is UC sub 5 sub H sub 5 sub C sub 8 sub H sub 8 sub , or uranium cyclopentadienide cyclooctatetraenide. Category Organic chemistry ... more details
Ionbox SystematicName Hydride ref Cite web url http pubchem.ncbi.nlm.nih.gov summary summary.cgi?cid 166653 title Hydride PubChem Public Chemical Database work The PubChem Project location USA publisher National Center for Biotechnology Information ref Section1 Chembox Identifiers CASNo 12184 88 2 PubChem 166653 PubChem Ref Pubchemcite correct pubchem ChemSpiderID 145831 ChemSpiderID Ref chemspidercite correct chemspider ChEBI 29239 Gmelin 14911 SMILES H StdInChI 1S H q 1 StdInChI Ref stdinchicite correct chemspider StdInChIKey KLGZELKXQMTEMM UHFFFAOYSA N StdInChIKey Ref stdinchicite correct chemspider Section2 Chembox Properties Formula Chem H MolarMass 1.00794 g mol sup 1 sup ExactMass 1.007825032 g mol sup 1 sup Section3 Chembox Thermochemistry Entropy 108.96 J K sup 1 sup mol sup 1 sup The hydrogen anion is a Electric charge negative hydrogen ion , H sup sup . It is an important constituent of the atmosphere of star s, such as the Sun , where it is the dominant absorber of photon s with energies in the range 0.75 4.0 electronvolt eV , ranging from the infrared into the visible spectrum Rau 1999 . It also occurs in the Earth s ionosphere Rau 1999 . Its existence was first proven theoretically by Hans Bethe in 1929 Bethe 1929 . H sup sup is unusual because it has no bound excited states, as was finally proven in 1977 Hill 1977 . It has been studied experimentally using particle accelerators Bryant 1977 . Chemical compounds that formally contain a hydrogen anion are called hydride s . Sources and references div class references small Bethe H. 1929 . Z. Phys. , 57 , 815 Bryant H.C. 1977 . Phys. Rev. Lett. 38 , 228 Hill R. N. 1977 . Phys. Rev. Lett. 38 , 643 Rau A. R. P. 1996 . http www.ias.ac.in jarch jaa 17 113 145.pdf The Negative Ion of Hydrogen , J. Astrophys. Astr. 17 , 113 Rau A. 1999 . The Negative Ion of Hydrogen , Chapter 5 of Srinivasan 1999 Srinivasan G. 1999 . From White Dwarfs to Black Holes The Legacy of S. Chandrasekhar , Chicago University of Chicago ... more details
for the observed threefold symmetry of the anion. Similarly, in a deprotonated carboxyl group ... 2, so the two oxygens are equivalent. The croconate anion chem C 5 O 5 2 also has fivefold symmetry ... acids An oxocarbon anion C sub x sub O sub y sub sup n sup can be seen as the result of removing ... sub sup 2 sup , for example, can be seen as the anion of carbonic acid H sub 2 sub CO sub 3 sub . Sometimes ... 2 sub . However, the anion is often more stable than the acid as is the case for carbonate ref http ... sup sub 4 sub . Neutralized species Every oxocarbon anion C sub x sub O sub y sub sup n sup can be matched ..., for example, the stable carbonate anion corresponds to the extremely unstable neutral carbon trioxide ... croconic acid croconate anion C sub 5 sub O sub 5 sub sup 2 sup corresponds to the neutral cyclopentanepentone ... rhodizonate C sub 6 sub O sub 6 sub sup 2 sup can be reduced to the tetrahydroxybenzoquinone THBQ anion ... doi 10.1021 ja9024897 ref Acid anhydrides An oxocarbon anion C sub x sub O sub y sub sup n sup can ... Gesellschaft volume 46 pages 813 815 ref Hydrogenated anions For each oxocarbon anion C sub ... anion td td tetrahydroxybenzoquinone CO sub 2 sub COH sub 4 sub THBQ td td td td cyclohexanehexone ... more details
the generation of an aryl radical anion, fragmentation, and bond formation with a nucleophile. Electron ... I species. Side reactions may also present a problem concentrations of the nitrile anion must ... Applications Alkylation of a nitrile anion followed by reductive decyanation was employed in the synthesis ... more details
Pfam box Symbol OATP Name Organic Anion Transporter Polypeptide OATP family image width caption Pfam PF03137 InterPro IPR004156 SMART Prosite SCOP TCDB 2.A.60 OPM family OPM protein PDB An organic anion ... anion s across the cell membrane . Organic anion transporting proteins belong to the solute carrier family , more specific, subfamily 21 organic anion transporting . ref name Hagenbuch 2004b cite journal author Hagenbuch B, Meier PJ title Organic anion transporting polypeptides of the OATP SLC21 ... doi 10.1007 s00424 003 1168 y ref Function Organic anion transporters may carry bile acid s as well ... anion transporting proteins have been found in human cells. class wikitable sortable border 1 Abbreviation Protein Name Location SLCO1A2 Solute carrier organic anion transporter family member 1A2 Liver SLCO1B1 Solute carrier organic anion transporter family member 1B1 Liver SLCO1B3 Solute carrier organic anion transporter family member 1B3 Liver SLCO1B4 SLCO1C1 SLCO2A1 SLCO2B1 Solute carrier organic anion transporter family member 2B1 Many SLCO3A1 Solute carrier organic anion transporter family member 3A1 SLCO4A1 Solute carrier organic anion transporter family member 4A1 OATP4C1 SLCO4C1 Kidneys SLCO5A1 SLCO6A1 Organic anion transporter OAT family The SLC22A gene family codes for organic anion transporter OAT proteins. The OAT family plays the central role in renal organic anion ... organic anion s from Blood plasma plasma . URAT1 transports those organic anions from the cytoplasm ... author Sekine T, Miyazaki H, Endou H title Molecular physiology of renal organic anion transporters ... pmid 16403838 doi 10.1152 ajprenal.00439.2004 ref Organic anion transporters are within the organic ... Location Organic anion transporter 1 OAT1 SLC22A6 Solute carrier family 22 member 6 br Brain, placenta ... membrane of the renal proximal tubule cells Pharmacology Probenecid inhibits organic anion transporters ... Organo Anion Transporter id Transporter anion organik ... more details
div style float right border solid 10px white Test sample values div The urine anion gap is calculated using measured ions found in the urine. ref name pmid8546137 Cite journal author Kim GH, Han JS, Kim YS, Joo KW, Kim S, Lee JS title Evaluation of urine acidification by urine anion gap and urine osmolal gap in chronic metabolic acidosis journal Am. J. Kidney Dis. volume 27 issue 1 pages 42 7 year 1996 month January pmid 8546137 doi 10.1016 S0272 6386 96 90029 3 url http linkinghub.elsevier.com retrieve pii S0272 6386 96 90029 3 ref It is used to aid in the differential diagnosis of metabolic acidosis . ref name urlUrine Anion Gap Acid Base Tutorial, University of Connecticut Health Center Cite web url http fitsweb.uchc.edu student selectives TimurGraham Urine Anion Gap.html title Urine Anion Gap Acid Base Tutorial, University of Connecticut Health Center work accessdate 2009 04 11 ref The term anion gap without qualification usually implies serum anion gap . The urine anion gap is a different measure, principally used to determine whether the kidneys are capable of appropriately acidifying urine. Calculation Urine anion gap is calculated by subtracting the urine concentration of chloride anions from the concentrations of sodium plus potassium cations ref name McMillanFeigin2006 cite book author1 Julia A. McMillan author2 Ralph D. Feigin author3 Catherine DeAngelis coauthors M. Douglas Jones title Oski s pediatrics principles & practice url http books.google.com books?id VbjFQiz8aR0C&pg RA1 PA1889 accessdate 14 November 2010 date 1 April 2006 publisher Lippincott Williams & Wilkins ... anion gap equation, the bicarbonate is excluded. This is because urine is acidic, so the bicarbonate level would be negligible. Uses Urine anion gap is an artificial and calculated measure that is representative ... NH sub 4 sub sup sup . A positive urine anion gap suggests a low urinary NH sub 4 sub sup sup e.g. renal tubular acidosis . A negative urine anion gap suggests a high urinary NH sub 4 sub sup ... more details
An alkali anion exchange membrane AAEM is a semipermeable membrane generally made from ionomer s and designed to conduct anions while being impermeable to gases such as oxygen or hydrogen . This is their essential function when incorporated into a membrane electrode assembly MEA of a DMFC ref http epubs.surrey.ac.uk cgi viewcontent.cgi?article 1061&context chemistry Comparison of PVDF and FEP based radiation grafted alkaline anionexchange membranes for use in low temperature portable DMFCs ref or DEFC ref http ecsmeet5.peerx press.org ms files ecsmeet5 2007 12 13 00000569 00 569 0 art 0 jt0484.pdf Direct ethanol fuel cells using alkaline anion exchange membrane dl date February 2012 ref separation of reactants and transport of anions. Advantage The advantage of the alkali anion exchange membrane in the fuel cell is the potential to use non noble metals such as iron , cobalt or nickel ref http www.reuters.com article environmentNews idUSL1461117220070914 Platinum free fuel cell developed in Japan ref due to the low overpotential s associated with electrochemical reactions at high pH ref http ecsmeet7.peerx press.org ms files ecsmeet7 2008 12 11 00000661 00 661 0 art 0 kbqbhk.pdf Poly phenylene based anion exchange membranes for alkaline fuel cells dl date February 2012 ref ref http www.electrochem.org meetings scheduler abstracts 214 0783.pdf Anion Exchange Membrane and Ionomer for Alkaline Membrane Fuel Cells dl date February 2012 ref . In comparison against Alkaline fuel cell , alkali anion exchange membrane fuel cells also protect the electrode from solid carbonate precipitation, which can cause fuel oxygen hydrogen transport problem during start up. See also Alkaline fuel cell Artificial membrane Gas diffusion electrode Ion exchange Glossary of fuel cell terms Proton exchange membrane Alkaline Anion Exchange Membrane Fuel Cells References reflist DEFAULTSORT Alkali Anion Exchange Membrane Category Fuel cells Category Electrochemistry Category Polymers Category Hydrogen ... more details
Infobox Disease Name PAGENAME Image Caption DiseasesDB 29144 ICD10 ICD10 E 87 2 e 70 ICD9 ICD9 276.2 ICDO OMIM MedlinePlus eMedicineSubj eMedicineTopic MeshID In renal physiology , normal anion gap acidosis , and less precisely non anion gap acidosis , is an acidosis that is not accompanied by an abnormally increased anion gap . The most common etiology of normal anion gap acidosis is diarrhea with a renal tubular acidosis being a distant second . Differential diagnosis The differential diagnosis of normal anion gap acidosis is relatively short when compared to the differential diagnosis of acidosis Hyperalimentation Acetazolamide and other carbonic anhydrase inhibitors Renal tubular acidosis ref name urlMetabolic Acidosis Acid Base Regulation and Disorders Merck Manual Professional cite web url http www.merck.com mmpe sec12 ch157 ch157c.html sec12 ch157 ch157c 1035 title Metabolic Acidosis Acid Base Regulation and Disorders Merck Manual Professional format work accessdate 2008 12 04 ref Diarrhea Ureteroenteric fistula an abnormal connection fistula between a ureter and the gastrointestinal tract Pancreaticoduodenal fistula an abnormal connection between the pancreas and duodenum It can be remembered with the mnemonic HARD UP . ref MedicalMnemonics 1797 ref As opposed to high anion gap acidosis which involves increased organic acid production , normal anion gap acidosis involves either increased production of chloride hyperchloremic acidosis or increased excretion of bicarbonate . One more commonly used older mnemonic is USED CAR U uterosigmoidostomy S saline administration in the face of renal dysfunction E endocrine Addisons, spironolactone, triamterene, amiloride, primary hyperparathyroidism D diarrhea C carbonic anhydrase inhibitors A ammonium chloride R renal tubular acidosis References references med stub Water electrolyte imbalance and acid base imbalance Category Nephrology pt Acidose de intervalo ani nico normal ... more details
Orphan date February 2009 Image Criticalradiusratio.png thumb 300px right Critical Radius Ratio In condensed matter physics the cation anion radius ratio is the ratio of the ionic radius of the cation to the ionic radius of the anion in a cation anion Chemical compound compound . This is simply given by math r C r A math The allowed size of the cation is determined by the critical radius ratio. If the cation is too small, then it will attract the anions into each other and they will collide hence the compound would collapse, this occurs when the radius ratio drops below 0.155. At the stability limit the cation is touching all the anions and the anions are just touching at their edges radius ratio 0.155 . Beyond this stability limit radius ratio 0.155 the compound will be Chemical stability stable . The below table gives the relation between radius ratio and coordination number class wikitable style text align center Radius Ratio Coordination number Type of void Example 0.155 0.225 3 Triangular Planar B sub 2 sub CO sub 3 sub 0.225 0.414 4 Tetrahedron Tetrahedral ZnS,CuCl 0.414 0.732 6 Octahedron Octahedral NaCl,MgO 0.732 1.000 8 Cubic CsCl,NH sub 4 sub Br Category Condensed matter physics Face centered cubic ... more details
Anion s that interact weakly with cation s are termed non coordinating anions , although a more accurate term is weakly coordinating anion . ref cite journal author I. Krossing and I. Raabe title Noncoordinating Anions Fact or Fiction? A Survey of Likely Candidates year 2004 journal Angewandte Chemie International Edition volume 43 issue 16 pages 2066 2090 doi 10.1002 anie.200300620 pmid 15083452 ref Non coordinating anions are useful in studying the reactivity of electrophilic cations. They are commonly found as counterions for cationic metal complex es with an 18 Electron rule unsaturated coordination sphere . These special anions are essential components of Homogeneous catalysis homogeneous Ziegler Natta catalyst olefin polymerisation catalysts , where the active catalyst is a coordinatively unsaturated, cationic transition metal complex. For example, they are employed as counterions for the electron counting 14 valence electron cations C sub 5 sub H sub 5 sub sub 2 sub ZrR sup sup R methyl or a growing polyethylene chain . Complexes derived from noncoordinating anions have been used ... Order of Anion Donor Strength year 1989 journal Inorganic Chemistry journal Inorganic Chemistry ... sup sup anion, commonly abbreviated as BAr sup F sup sub 4 sub sup sup and affectionately called ... issue 14 pmc 2600718 ref This anion is far less coordinating than the tetrafluoroborate BF sub 4 ... to electrophilic centers, in which cases, the use of a noncoordinating anion is pointless. Salts of the anion B 3,5 CF sub 3 sub sub 2 sub C sub 6 sub H sub 3 sub sub 4 sub sup sup were first reported by Kobayashi and co workers. For that reason, it is sometimes referred to as Kobayashi s anion ... anions Another large class of non coordinating anions are derived from carborane anion CB sub 11 sub H sub 12 sub sup sup . Using this anion, the first example of a three coordinate silicon ... anion derived from a carborane . ref cite journal author Kim, K. C. Reed, C. A. Elliott, D ... more details
In chemistry , the term pseudo oxocarbon anion is used to refer to a anion negative ion that is conceptually derived from an oxocarbon anion through replacement of one or more of the basic oxygen atoms by chemically similar elements or functional group s, such as sulfur S , selenium Se , or dicyanomethylene C CN sub 2 sub . Typical examples are the anions 2 dicyanomethylene croconate , croconate violet , and croconate blue , derived from the croconate anion chem C 5 O 5 2 by replacing one, two, or three oxygen atoms by dicyanomethylene groups blockquote table border 0 cellborder 0 cellpadding 6px tr valign middle td align center File chemfm cyclopentanepentone 2neg.svg 78px td td align center File chemfm 2 dicyanomethylene croconate 2neg.svg 78px td td align center File chemfm croconate violet 2neg.svg 132px td td align center File chemfm croconate blue 2neg.svg 132px td tr tr valign top td align center Croconate td td align center 2 Dicyanomethylene br croconate td td align center Croconate violet td td align center Croconate blue td tr table blockquote These anions retain many of the properties of the parent, including the delocalized bond in the ring and the delocalized charge in the atoms attached to the ring. ref name fati Alexander J. Fatiadi 1978 , Synthesis of 1,3 dicyanomethylene croconate salts. New bond delocalized dianion, Croconate Violet . Journal of the American Chemical Society, volume 100 issue 8, pages 2586 2587. doi 10.1021 ja00476a073 ref ref name fati2 Alexander J. Fatiadi 1980 , Pseudooxocarbons. Synthesis of 1,2,3 tris dicyanomethylene croconate salts. A new bond delocalized dianion, croconate blue . Journal of Organic Chemistry volume 45, pages 1338 1339. doi 10.1021 jo01295a044 ref ref name doane Lawrence M. Doane, Alexander J. Fatiadi 2003 Electrochemical Oxidation of Croconate Salts Evidence of the Chemical Equivalence of the Carbonyl Oxygen Atom and the Dicyanomethylene Group doi 10.1002 anie.198206351 ref Similar anions can be obtained from ... more details
pmid10954321 br The membrane is represented in light brown. The organic anion transporter 1 OAT1 also ... anion transporter Organic anion transporter OAT family organic anion transporter OAT family of proteins ... tubule proximal tubular cells of the kidneys. It plays a central role in renal organic anion transport ... . ref name pmid16403838 Function PBB geneid 9356 OAT1 functions as organic anion exchanger. When the uptake of one molecule of an organic anion is transported into a cell by an OAT1 exchanger ... transporter also grinds to a halt. ref name pmid17356845 The renal organic anion transporters ... journal author Sekine T, Cha SH, Endou H title The multispecific organic anion transporter OAT family ... Gene SLC22A6 solute carrier family 22 organic anion transporter , member 6 url http www.ncbi.nlm.nih.gov ... cite journal author Sekine T, Miyazaki H, Endou H title Molecular physiology of renal organic anion ... organic anion transporter 1 rOAT1 transports zidovudine, acyclovir, and other antiviral nucleoside ... of human renal organic anion transporter 1 journal J. Am. Soc. Nephrol. volume 11 issue 3 pages ... and functional expression of a multispecific organic anion transporter from human kidney journal ... novel human renal organic anion transporters hOAT1 and hOAT3 journal Biochem. Biophys. Res. Commun ... are novel substrates for human and rat renal organic anion transporter 1 journal Mol. Pharmacol ... D, et al. title Genomic structure and in vivo expression of the human organic anion transporter ... Human organic anion transporters mediate the transport of tetracycline journal Jpn. J. Pharmacol. volume ... anion transporter 1 journal Am. J. Physiol. Renal Physiol. volume 284 issue 3 pages F503 9 year 2003 ... human organic anion transporter 1 mediated transport through carrier internalization journal J ... on basolateral organic anion uptake in rabbit proximal renal tubules and hOAT1 expressed in human ... Tanaka K, Xu W, Zhou F, You G title Role of glycosylation in the organic anion transporter OAT1 journal ... more details
, Craigen WJ title A novel mouse mitochondrial voltage dependent anion channel gene localizes to chromosome ..., there is a voltage dependent switch between an anion selective high conductance state with high ... Voltage Dependent Anion Channels membrane protein stub Ion channels g4 InterPro content IPR001925 ... more details
Infobox Disease Name High anion gap metabolic acidosis Image Caption DiseasesDB 15112 ICD10 ICD10 E 87 2 e 70 ICD9 ICD9 276.2 ICDO OMIM MedlinePlus eMedicineSubj eMedicineTopic MeshID High anion gap metabolic acidosis is a form of metabolic acidosis characterized by a high anion gap . The list of agents that cause high anion gap metabolic acidosis is similar to but broader than the list of agents that cause a serum osmolal gap . Causes Causes include Mudpiles The mnemonic MUDPILES is commonly used to remember the causes of increased anion gap metabolic acidosis. ref MedicalMnemonics 1203 3255 ref ref http fitsweb.uchc.edu student selectives TimurGraham Anion Gap.html Anion Gap Acid Base Tutorial, University of Connecticut Health Center Bot generated title ref M Methanol U Uremia chronic renal failure D Diabetic ketoacidosis P Propylene glycol P used to stand for Paraldehyde but substance is not commonly used today I Infection , Iron , Isoniazid , Inborn errors of metabolism L Lactic acidosis E Ethylene glycol Note Ethanol is sometimes included in this mnemonic as well, although the acidosis caused by ethanol is actually primarily due to the increased production of lactic acid found in such intoxication. S Salicylates Another frequently used mnemonic is KARMEL. K Ketoacidosis A acetylsalicylic acid ASA R Renal failure M Methanol E Ethylene glycol L Lactic acidosis Another frequently used mnemonic is KUPIN. K Ketoacidosis DKA , Alcoholic ketoacidosis AKA U Uremia P Production Lactic acidosis I Ingestion Ethylene glycol , methanol N Need to Remember ASA , Metformin Other formaldehyde toluene sulfates metformin ref name pmid12380915 cite journal author Chang CT, Chen YC, Fang JT, Huang CC title High anion gap metabolic acidosis in suicide don t forget metformin intoxication two patients experiences journal Ren Fail volume 24 issue 5 pages 671 5 year 2002 month September pmid 12380915 doi 10.1081 JDI 120013973 url ref rhabdomyolysis ref name urlMetabolic Acidosis Acid Base ... more details
Alkaline Anion Exchange Membrane Fuel Cells AAEMFC also known as Hydroxide Ion Exchange Fuel Cells are a type of Alkaline fuel cells . Alkaline fuel cells AFCs , one of the oldest type of fuel cell , operate between ambient temperature and 90 C with an electrical efficiency higher than the other fuel cells such as proton exchange membrane fuel cell s, solid oxide fuel cell s and phosphoric acid fuel cell s. Alkaline anion exchange membrane fuel cells AAEMFCs are functionally similar to AFCs, the difference being AAEMFCs employ a solid polymer electrolyte while AFCs use aqueous KOH as an electrolyte . gallery File AAEMFC.jpg Alkaline anion exchange membrane fuel cell gallery Science Reactions In an AAEMFC, the fuel, hydrogen or methanol, is supplied at the anode and oxygen through air, and water are supplied at cathode . Fuel is oxidized at anode and oxygen is reduced at cathode. At cathode, oxygen reduction produces hydroxides ions OH sup sup that migrate through the elctrolyte towards the anode. At anode, hydroxide ions react with the fuel to produce water and electrons. Electrons go through the circuit producing current. ref cite journal last Winter first M coauthors Brodd, R. J. title What are batteries, fuel cells, and supercapacitors? journal Chemical Reviews year 2004 volume 104 issue 10 pages 4245 4269 ref Electrochemical Reactions when hydrogen is the fuel At Anode 2H sub 2 sub 4OH sup sup 4H sub 2 sub O 4e sup sup At cathode 3 2O sub 2 sub 3H sub 2 sub O 6e sup sup 6OH sup sup Electrochemical Reactions when methanol is the fuel At anode CH sub 3 sub OH 6OH sup sup CO .... In alakline anion exchange membrane fuel cell, aqueous KOH is replaced with a solid polymer electrolyte ... Slade, R. C. T. title Prospects for Alkaline Anion Exchange Membranes in Low Temperature Fuel ... in developing AAEMFCs is the anion exchange membrane AEM . A typical AEM is composed of a polymer ... of Nafion used for PEMFCs, where an anion is covalently attached to the polymer ... more details
Orphan date January 2011 The Barton Zard Synthesis method of pyrrole synthesis is a cyclisation reaction between a nitroalkene and isocyanoacetate under base conditions. ref J. Jack Li, Heterocyclic Chemistry, 2005, 1, 70. ref Image Barton Zard reaction.png center 450px Mechanism It consists in three main steps Michael type addition between the isocyanide carbonyl enolate and the nitroalkene. Cyclization between isocyanide s carbene and the anion formed in the position of Nitro compound nitro group. Elimination of nitro group with consecuent aromatization. ref name Li cite book author Jie Jack Li title Name Reactions. A Collection of Detailed Reaction Mechanisms 4th Edition publisher Springer location Berlin, De year 2009 isbn 978 3 642 01052 1 ref Image Barton Zard mechanism.png center 650px References reflist Category Heterocycle forming reactions Category Name reactions chemistry stub es S ntesis de pirroles de Barton Zard ... more details
enolateanion . There are a number of different combinations of enolizable and nonenolizable ... by a strong base, resulting in the formation of an enolateanion, which is made relatively stable ... is nucleophilically attacked by the enolateanion. The alkoxy group is then eliminated resulting ... a new, highly resonance stabilized enolateanion. Aqueous acid e.g. sulfuric acid or phosphoric acid is added in the final step to neutralization neutralize the enolate and any base still present. The newly ... more details
In organic chemistry ketone halogenation is a special type of halogenation . The position alpha next to the carbonyl group in a ketone is easily halogenated, due to the ability to form an enolate anion enolate in basic chemistry basic solution, or an enol in acidic solution. An example is the bromination of acetone in basic solution big CH sub 3 sub CO CH sub 3 sub OH sup sup CH sub 3 sub CO CH sub 2 sub sup sup H sub 2 sub O big big CH sub 3 sub CO CH sub 2 sub sup sup Br sub 2 sub CH sub 3 sub CO CH sub 2 sub Br Br sup sup big Image with unknown copyright status removed Image Acetone Bromination.GIF In acidic solution, usually only one alpha hydrogen is replaced by a halogen, because each successive halogenation is slower that the first. The halogen decreases the basicity of the carbonyl oxygen, thus making protonation less likely. However, in basic solution successive halogenations are more rapid , because the halogen withdraws electrons by induction and makes remaining hydrogens more acidic. In the case of methyl ketone s, this results in what is called the haloform reaction . ref Organic Chemistry Fifth Edition, by Paula Yurkanis Bruice. Pearson Prentice Hall, Upper Saddle River, NJ, 2007 ref References reflist 2 Category Substitution reactions reaction stub es Halogenaci n de cetonas mk nl Ketonhalogenering pt Halogena o de cetona ... more details
The Varrentrapp reaction is an organic reaction involving the chemical decomposition of an , saturation chemistry unsaturated carboxylic acid acid into two other acid fragments by action of molten alkali . This reaction pioneered by F. Varrentrapp in 1840 ref F. Varrentrapp, Ann., 36, 196 1840 ref has been of some importance in structure elucidation of certain fatty acid s but has no practical synthetic use. ref Organic reactions in strong alkalis I Fission of ethylenic acids the varrentrapp reaction Tetrahedron journal Tetrahedron , Volume 8, Issues 3 4, 1960 , Pages 221 238 R. G. Ackman, Patrick Linstead, B. J. Wakefield and B. C. L. Weedon doi 10.1016 0040 4020 60 80031 2 ref ref A Mechanism for the Cleavage of Unsaturated Acids with Molten Alkali William A. Bonner, Robert T. Rewick J. Am. Chem. Soc. 1962 84 12 2334 2337. DOI 10.1021 ja00871a013 ref The original 1840 Varrentrapp reaction concerned the conversion of oleic acid to palmitic acid , acetic acid and hydrogen gas Image VarrentrappReaction.svg 600px center The Varrentrap reaction the reaction conditions are harsh medium molten potassium hydroxide at temperatures in the range of 250 to 300 C . Likewise cinnamic acid is converted to benzoic acid . The reaction mechanism for this reaction is outlined below. Although the alkene group in the fatty acid can be located at more than one position in the chain, this does not affect the nature of the reaction products. This is because the double bond always migrates to the position next to the carboxylic acid group prior to cleavage. The next step is nucleophilic addition of a hydroxyl anion to the double bond of 1 followed by proton migration to intermediate 3 . The next step is cleavage to enolate 4a and aldehyde 4b . The enolate on acidic workup will form acetic acid. The aldehyde continues to react with another equivalent of base forming carboxylate 7 together with hydrogen. The hydride transfer is akin the Cannizzaro reaction . Image VarrentrappMechanism3.sv ... more details
enol tautomerism occurs the keto or enol is deprotonated and an anion, which is called the enolate ... and enolate deprotonation of the C atom. Enolateanion, described is terms of Resonance chemistry resonance . Left the carbanion . Interconversion between enolate and enol protonation of the enolate ... of ascorbic acid vitamin C , converting an enediol left into an enolate right clear Enolates in MO theory Image Enolate pi MOs.png thumb right Enolate MOs Later theories of chemical bonding, particularly ... that they can also be seen as waves creating a standing wave pattern around all the atoms. Enolate ... example with charge distribution values clear Selective deprotonation in enolate forming In ketones ... to generate two different enolate structures. At low temperatures 78 C, i.e. dry ice bath , in aprotic ... between the ketone and the two possible enolates, the enolate favoured is termed the thermodynamic enolate and is favoured because of its lower energy level than the other possible enolate ... opposite regiochemical results Thus, by choosing the optimal conditions to generate an enolate ... more details
anion, derived from an organic carboxylic acid cf. acetic acid , and the corresponding vinylogous carboxylate anion the vinylog vinylogue of the carboxylate anion , where a vinyl group now separates ... enolate see first and following image . The vinylogous enolate attacks with the terminal ... to the carbonyl the carbon position, as in a simple enolate . Allylic nucleophiles often react ... charge on the resulting anion conjugate base of ascorbic acid center and right structures in last image , analogous to the two resonance structures that stabilize the negative charge on the anion that results ... more details
Radical nucleophilic aromatic substitution or S sub RN sub 1 in organic chemistry is a type of substitution reaction in which a certain substituent on an aromatic compound is replaced by a nucleophile through an intermediary free radical species Image Radical nucleophilic aromatic substitution overview.png 300px center Radical nucleophilic aromatic substitution overview The substituent X is a halide and nucleophiles can be sodium amide , an alkoxide or a carbon nucleophiles such as an enolate . ref Phenomenon of radical anion fragmentation in the course of aromatic SRN reactions Roberto A. Rossi Acc. Chem. Res. 1982 15 6 pp 164 170 DOI 10.1021 ar00078a001 . ref In contrast to regular nucleophilic aromatic substitution , deactivating group s on the arene are not required. ref Rossi, R. A. Pierini, A. B. Santiago, A. N. Org. React. 1999 , 54 , 1.doi http dx.doi.org 10.1002 0471264180.or054.01 10.1002 0471264180.or054.01 ref This reaction type was discovered in 1970 by Bunnett and Kim ref Evidence for a radical mechanism of aromatic nucleophilic substitution Joseph F. Bunnett and Jhong Kook Kim J. Am. Chem. Soc. 1970 92 25 pp 7463 7464. DOI 10.1021 ja00728a037 ref and the abbreviation S sub RN sub 1 stands for substitution radical nucleophilic unimolecular as it shares properties with an aliphatic SN1 reaction . An example of this reaction type is the Sandmeyer reaction . Reaction mechanism Image Radical nucleophilic aromatic substitution Mechanism.png 400px center Radical nucleophilic aromatic substitution Mechanism In this radical substitution the aryl halide 1 accepts an electron from an radical initiator forming a radical anion 2 . This intermediate collapses into an aryl radical 3 and a halide anion. The aryl radical reacts with the nucleophile 4 to a new radical anion 5 which goes on to form the substituted product by transferring its electron to new aryl halide in the chain propagation . Alternatively the phenyl radical can abstract any loose proton from 7 formi ... more details
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