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[[File:Quaternary ammonium cation.svg|thumb|right|Quaternary ammonium cation. The R groups may be the same or different alkyl or aryl groups. Also, the R groups may be connected.]]
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'''[[Quaternary compound|Quaternary]] ammonium cations''', also known as '''quats''', are positively charged [[polyatomic ion]]s of the structure NR<sub>4</sub><sup>+</sup>, R being an [[alkyl]] group or an [[aryl]] group.<ref>{{GoldBookRef | file = Q05003 | title = quaternary ammonium compounds }}</ref> Unlike the [[ammonium|ammonium ion]] (NH<sub>4</sub><sup>+</sup>) and the primary, secondary, or tertiary ammonium [[cations]], the quaternary ammonium cations are permanently charged, independent of the [[pH]] of their solution. '''Quaternary ammonium salts''' or '''quaternary ammonium compounds''' (called '''quaternary amines''' in oilfield parlance) are [[salt (chemistry)|salt]]s of quaternary ammonium cations with an [[anion]].
 
== Synthesis ==
Quaternary ammonium compounds are prepared by [[alkylation]] of tertiary amines, in a process called '''quaternization'''.<ref>{{March5th}}</ref> Typically one of the alkyl groups on the amine is larger than the others.<ref>Kosswig, K. “Surfactants” in Ullmann’s Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. {{DOI|10.1002/14356007.a25_747}}.</ref> A typical synthesis is for [[benzalkonium chloride]] from a long-chain alkyldimethylamine and [[benzyl chloride]]:
:CH<sub>3</sub>(CH<sub>2</sub>)<sub>n</sub>N(CH<sub>3</sub>)<sub>2</sub>  +  ClCH<sub>2</sub>C<sub>6</sub>H<sub>5</sub>  →  [CH<sub>3</sub>(CH<sub>2</sub>)<sub>n</sub>N(CH<sub>3</sub>)<sub>2</sub>CH<sub>2</sub>C<sub>6</sub>H<sub>5</sub>]<sup>+</sup>Cl<sup>-</sup>
 
==Reactions==
While not very reactive, quaternary ammonium salts undergo [[Sommelet–Hauser rearrangement]]<ref>{{OrgSynth | collvol = 4 | collvolpages = 585 | year = 1963 | title = 2-Methylbenzyldimethylamine | author1 = W. R. Brasen | author2 = C. R. Hauser}}</ref> and [[Stevens rearrangement]],<ref>{{cite journal | doi = 10.1002/0471264180.or018.04 | chapter = The Base-Promoted Rearrangements of Quaternary Ammonium Salts | title = Organic Reactions | year = 2011 | last1 = Pine | first1 = Stanley H. | isbn = 0471264180}}</ref> as well as dealkylation under harsh conditions. Quaternary ammonium cations can also undergo the [[Hofmann Elimination]] and [[Emde degradation]] if there are hydrogens beta to the nitrogen.
 
==Applications==
Quaternary ammonium salts are used as [[disinfectant]]s, [[surfactants]], [[fabric softener]]s, and as [[antistatic agent]]s (e.g. in [[shampoo]]s). In [[liquid]] fabric softeners, the [[chloride]] salts are often used. In [[clothes dryer|dryer]] [[fabric softener|anticling]] strips, the [[sulfate]] salts are often used. Spermicidal jellies also contain quaternary ammonium salts.
 
===As antimicrobials===
Quaternary ammonium compounds have also been shown to have antimicrobial activity.<ref>{{cite journal | doi = 10.1016/S0008-6215(01)00112-4 | title = Synthesis and antibacterial activities of quaternary ammonium salt of chitosan | year = 2001 | last1 = Jia | first1 = Zhishen | last2 = Shen | first2 = Dongfeng | last3 = Xu | first3 = Weiliang | journal = Carbohydrate Research | volume = 333 | pages = 1–6 | pmid = 11423105 |issue=1}}</ref> Certain quaternary ammonium compounds, especially those containing long alkyl chains, are used as [[antimicrobial]]s and [[disinfectant]]s. Examples are [[benzalkonium chloride]], [[benzethonium chloride]], methylbenzethonium chloride, cetalkonium chloride, [[cetylpyridinium chloride]], [[cetrimonium]], [[cetrimide]], dofanium chloride, [[tetraethylammonium bromide]], [[didecyldimethylammonium chloride]] and domiphen bromide. Also good against fungi, amoeba, and enveloped viruses,<ref name=questionable>[http://www.mansfield.ohio-state.edu/~sabedon/biol2032.htm ''Specific Antimicrobials''], outline of lecture by Stephen T. Abedon, Ohio State U., URL accessed Dec 2008.</ref> quats act by disrupting the cell membrane.{{citation needed|date=January 2013}} Quaternary ammonium compounds are lethal to a wide variety of organisms except [[endospores]], ''[[Mycobacterium tuberculosis]]'' and [[non-enveloped virus]]es.
 
In contrast to phenolics, quaternary ammonium compounds are not very effective in the presence of organic compounds. Yet, they are very effective in combination with phenols. Quaternary ammonium compounds are deactivated by soaps, other anionic detergents, and cotton fibers.<ref name=questionable/> Also, they are not recommended for use in hard water. Effective levels are at 200 ppm.<ref>[http://mark.asci.ncsu.edu/HealthyHogs/book1993/ladd1.htm ''The Use of Disinfectants In the Swine Industry''], Mark G. Ladd, North Carolina State Univ., URL accessed Dec 2008.</ref> They are effective at temperatures up to {{convert|212|F|C|abbr=on}}.
 
Quaternary ammonium salts are popular chemicals used in [[foodservice]] industry as sanitizing agents.
 
===As phase transfer catalysts===
In organic synthesis, quaternary ammonium salts are employed as [[phase transfer catalyst]]s ('''PTC'''). Such catalysts accelerate reactions between reagents dissolved in immiscible solvents. The highly reactive reagent [[dichlorocarbene]] is generated via PTC by reaction of chloroform and sodium hydroxide.
 
===Osmolytes===
Quaternary ammonium compounds are present in [[osmolyte]]s, specifically [[glycine betaine]], which stabilize osmotic pressure in cells.<ref>http://dx.doi.org/10.1128/AEM.67.6.2692-2698.2001 Sleator, Roy D., Wouters, Jeroen, Gahan, Cormac G. M., Abee, Tjakko, Hill, Colin
Analysis of the Role of OpuC, an Osmolyte Transport System, in Salt Tolerance and Virulence Potential of Listeria monocytogenes
Appl. Environ. Microbiol. 2001 67: 2692-2698</ref>
 
===Plant growth retardants===
Cycocel (chlormequat chloride) reduces plant height by inhibiting the production of gibberellins, the primary plant hormones responsible for cell elongation. Therefore, their effects are primarily on stem, petiole and flower stalk tissues. Lesser effects are seen in reductions of leaf expansion, resulting in thicker leaves with darker green color.<ref>http://users.in.gr/dimpet/thesis/growth_retardants.htm Wageningen Agricultural University, The Netherlands</ref>
 
== Health effects ==
Quaternary ammonium compounds can display a range of health effects, amongst which are mild skin and respiratory irritation <ref>{{cite journal | doi = 10.1186/1476-069X-8-11 | title = Characterization of occupational exposures to cleaning products used for common cleaning tasks-a pilot study of hospital cleaners | year = 2009 | last1 = Bello | first1 = Anila | last2 = Quinn | first2 = Margaret M | last3 = Perry | first3 = Melissa J | last4 = Milton | first4 = Donald K | journal = Environmental Health | volume = 8 | pages = 11 | pmid = 19327131 | pmc = 2678109}}</ref> up to severe caustic burns on skin and gastro-intestinal lining (depending on concentration), gastro-intestinal symptoms (e.g., nausea and vomiting), coma, convulsions, hypotension and death.<ref>[http://www.inchem.org/documents/pims/chemical/pimg022.htm#SectionTitle:2.1%20%20Main%20risk%20and%20target%20organs Quaternary ammonium (PIM G022)]</ref>
 
They are thought to be the chemical group responsible for [[anaphylactic reaction]]s that occur with use of [[neuromuscular blocking drug]]s during [[general anaesthesia]] in [[surgery]].<ref>{{cite journal | pmid = 19143700 | year = 2009 | last1 = Harper | first1 = NJ | last2 = Dixon | first2 = T | last3 = Dugué | first3 = P | last4 = Edgar | first4 = DM | last5 = Fay | first5 = A | last6 = Gooi | first6 = HC | last7 = Herriot | first7 = R | last8 = Hopkins | first8 = P | last9 = Hunter | first9 = JM | last10 = Mirakian | first10 = R | last11 = Pumphrey | first11 = RS | last12 = Seneviratne | first12 = SL | last13 = Walls | first13 = AF | last14 = Williams | first14 = P | last15 = Wildsmith | first15 = JA | last16 = Wood | first16 = P | last17 = Nasser | first17 = AS | last18 = Powell | first18 = RK | last19 = Mirakhur | first19 = R | last20 = Soar | first20 = J | author21 = Working Party of the Association of Anaesthetists of Great Britain Ireland | title = Suspected anaphylactic reactions associated with anaesthesia | volume = 64 | issue = 2 | pages = 199–211 | doi = 10.1111/j.1365-2044.2008.05733.x | pmc = 3082210 | journal = Anaesthesia}}</ref> [[Quaternium-15]] is the single most often found cause of allergic [[contact dermatitis]] of the hands (16.5% in 959 cases)<ref>{{cite journal | pmid = 17553593 | year = 2007 | last1 = Warshaw | first1 = EM | last2 = Ahmed | first2 = RL | last3 = Belsito | first3 = DV | last4 = Deleo | first4 = VA | last5 = Fowler Jr | first5 = JF | last6 = Maibach | first6 = HI | last7 = Marks Jr | first7 = JG | last8 = Toby Mathias | first8 = CG | last9 = Pratt | first9 = MD | last10 = Rietschel | first10 = RL | last11 = Sasseville | first11 = D | last12 = Storrs | first12 = FJ | last13 = Taylor | first13 = JS | last14 = Zug | first14 = KA | author15 = North American Contact Dermatitis Group | title = Contact dermatitis of the hands: Cross-sectional analyses of North American Contact Dermatitis Group Data, 1994-2004 | volume = 57 | issue = 2 | pages = 301–14 | doi = 10.1016/j.jaad.2007.04.016 | journal = Journal of the American Academy of Dermatology}}</ref>
 
===Reproductive effects of trace amounts===
Quaternary ammonium-based disinfectants (Virex and Quatricide) were tentatively identified ''(by researcher Patricia Hunt - who previously uncovered the reproductive system effects of [[bisphenol A]])'' and were also identified by researchers at other labs, as the most probable cause of jumps in birth defects and fertility problems in caged lab mice.<ref name="mice">{{cite journal | doi = 10.1038/453964a |date=June 2008 | author = Hunt, P | title = Lab disinfectant harms mouse fertility. Patricia Hunt interviewed by Brendan Maher | volume = 453 | issue = 7198 | pages = 964 | pmid = 18563110 | journal = Nature }}</ref>
 
===Quantification===
As [[quaternary ammonium compounds]] are classified as large volume chemicals (extensively used as antimicrobial agents, [[herbicides]] and detergents), they are one of the major environmental contaminants. Therefore, it is of interest to know about their impact on ecosystem. However, their quantification from environmental and biological samples is a major problem using conventional chromatography techniques as they are highly soluble in water. Interestingly, while analyzing them by [[liquid chromatography–mass spectrometry|liquid chromatography coupled tandem mass spectrometry]] it has been found that they follow an exception rule. Under standard [[electrospray ionization]] (ESI) conditions mono- and di-quaternary ammonium compounds form molecular ions with the formula of <math>m^q / z^q</math> rather than <math>( m + z )/ z</math>. Formation of <math>m^q / 2</math> is observed for di-quaternary ammonium compounds (like [[diquat]]) as precursor ion and <math>m^q / 1</math> as product ion due to the loss of one of the quaternary charge during CID. In di-quaternary ammonium compounds, this process can also result in the formation of fragment ions with higher mass as compared to their precursor ion. [[Hydrophilic interaction liquid chromatography|Hydrophilic interaction liquid chromatographic]] separation has been reported to demonstrate a successful separation of quaternary ammonium compounds for their quantification in ESI-MS/MS with higher precision.<ref>{{cite journal |doi =10.1080/00032719.2012.693140 |date= October 2012 |author1=Thirumurthy Velpandiana |author2=Jayabalan Nirmala |author3=Beauty Aroraa |author4=Alok Kumar Ravia |author5=Ankita Kotnalaa |title=Understanding the Charge Issues in Mono and di-Quaternary Ammonium Compounds for Their Determination by LC/ESI-MS/MS |volume=45 |issue=16 |pages=2367–2376 |journal=Analytical Letters}}</ref>
 
== See also ==
* [[Benzalkonium chloride]], [[benzethonium chloride]], methylbenzethonium chloride, cetalkonium chloride, [[cetylpyridinium chloride]], [[cetrimonium]], [[cetrimide]], dofanium chloride, [[tetraethylammonium bromide]], and domiphen bromide – [[antimicrobial]] ingredients found in various over-the-counter products
* [[Diquat]] -diquaternary ammonium compound recognized as a contact herbicide
* [[Carnitine]]
* [[Cetyl trimethylammonium bromide]] (CTAB), [[stearalkonium chloride]] – [[cationic]] [[surfactant]]s commonly used in toiletries
* [[Choline]]
* [[Cocamidopropyl betaine]] (CAPB), a common [[Zwitterion]]ic [[surfactant]] used ubiquitously in toiletries
* [[Denatonium]], the most bitter compound known
* [[Dimethyldioctadecylammonium chloride]]
* [[Paraquat]], an herbicide
* [[Polyquaternium]], designations for quaternary ammonium-containing polymers used for personal care products
* [[Quaternary ammonium muscle relaxants]]
* [[Tetra-n-butylammonium bromide]] and [[Aliquat 336]], common [[phase transfer catalyst]]s
* [[Tetramethylammonium chloride]]
* [[Tetramethylammonium hydroxide]]
* [[Tetramethylammonium pentafluoroxenate]], containing the unusual pentagonal pentafluoroxenate (XeF<sub>5</sub><sup>-</sup>) ion
* [[Triazene cleavage]]
 
== References ==
{{reflist}}
 
==External links==
* [http://www.inchem.org/documents/pims/chemical/pimg022.htm Toxicities of quaternary ammonium]
 
[[Category:Quaternary ammonium compounds| ]]
[[Category:Disinfectants]]
[[Category:Food safety]]

Revision as of 15:46, 19 February 2014

Hello. Allow me introduce the author. Her title is Emilia Shroyer but it's not the most female title out there. Hiring is his profession. California is our beginning location. To gather cash is what his family members and him enjoy.

my web-site ... healthy food delivery