Infobox Top level domain name .ph background CCF image Image Dotph.jpg 240px dotPH The Official Domain ... dotPH Domains Inc. sponsor PH Domain Foundation intendeduse Entities connected with the PHL actualuse ... through the .i.ph domain. Was reportedly marketed as global domain with .ph standing for phone ... document disputepolicy UDRP website URL www.dot.ph .ph is the Internet country code top level domain ccTLD for the Philippines . Introduction The official domain registry of the .ph domain is dotPH ... . Retrieved on May 30, 2008. ref dotPH holds and maintains the database of PH domain names, specifically .ph , .com.ph , .net.ph , .org.ph , .mil.ph , .ngo.ph and .i.ph . ref http dotph.domains.ph ..., 2008. ref ref name i ph site http www.i.ph i.ph Website . Retrieved on May 30, 2008. ref Its registrars ... parts of the world. ref name about dotph The PH domain is currently administered by Jose Emmanuel Joel Disini , ref name ph whois http www.iana.org domains root db ph.html .ph Whois information , Internet ... in 1990. ref name phildac whitepaper http www.ph.net phildac whitepaper.html The PH Domain and the Need for Policy Reforms . Retrieved on May 30, 2008. ref ref name jed i ph winthrop Disini, Joel ... by the PH Domain Foundation , ref name ph whois a social outreach arm of dotPH which was also ... www.phdf.org.ph profile.html PH Domain Foundation Profile Background , PH Domain Foundation website ... free blogging services through .i.ph domains. ref name dotph releases iph ref name i ph site Second ... Managed by PHNET .edu.ph Educational institutions History The Birth of the .ph Registry In 1989, Joel ... Business Sunday column. Quoted in full at the http www.phdf.org.ph news 07012001.html PH Domain ..., California, became Jon Postel s basis for delegating the .ph domain to him. ref name jed i ph winthrop The .ph country code top level domain was officially delegated on September 14, 1990. ref name ph whois Since then, .ph domains became commercially available to EMC customers. ref name phildac whitepaper ... more details
Other uses PH disambiguation lowercase title pH Acids and Bases In chemistry , pH is a measure of the acid ity or Base chemistry basicity of an aqueous solution . Pure water is said to be neutral, with a pH close to 7.0 at convert 25 C F abbr on lk on . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are Base chemistry basic or alkaline . pH measurements ... , civil engineering and many other applications. In a solution pH approximates but is not equal to p ... H 3 O a low pH indicates a high concentration of hydronium ions, while a high pH indicates a low concentration ..., for example, 0.1 molar concentration molar hydrochloric acid should be near pH 1 and 0.0001 molar HCl should be near pH 4 the base 10 logarithms of 0.1 and 0.0001 being 1, and 4, respectively . Pure ... of the 0 to 14 pH scale , giving it a pH of 7 at convert 25 C F abbr on lk on , or 0.0000001 M H ... II, Acid Base Reactions ref For an aqueous solution to have a higher pH, a base must be dissolved ... acidic pH level. However, pH is not precisely p H , but takes into account an activity chemistry ... of the solution, which affects among other things the electrical potential read using a pH meter . As a result, pH can be affected by the ionic strength of a solution for example, the pH of a 0.05 M potassium hydrogen phthalate solution can vary by as much as 0.5 pH units as a function of added ... journal doi 10.1021 ac60120a014 title Use and Abuse of pH measurements journal Analytical Chemistry ... thermodynamically sound method, so they are based on theoretical calculations. Therefore, the pH scale is defined in practice as traceable to a set of standard solutions whose pH is established by international ... prs.pdf title The Measurement of pH Definition, Standards and Procedures Report of the Working Party on pH, IUPAC Provisional Recommendation year 2001 A proposal to revise the current IUPAC 1985 and ISO 31 8 definition of pH. ref Primary pH standard values are determined by the Harned cell , a hydrogen ... more details
Letter NumberCombination PG PI OH QH wiktionarypar PHpHpH is a measure of acidity or alkaline in chemistry. PH , ph , pH , and Ph may also refer to Sciences PH complexity , the union of all people classes in the polynomial hierarchy in computational complexity theory Ph.D , Philosophi Doctor Latin Phenyl group , either Ph or , highly stable and aromatic hydrocarbon unit found in many organic compounds phot , or ph, a measurement of illuminance photometry pico pico henry unit henry , an SI Unit of electrical inductance Pleckstrin homology domain, a part of many proteins which bind phosphoinositides with high affinity Pulmonary hypertension , a medical condition Soil pH is a measure of soil acidity or soil alkalinity. Aviation Aircraft registration PH Papa, Hotel , Aircraft Registration prefix for the Netherlands Polynesian Airlines IATA airline designator Transavia.com Denmark s IATA airline designator See also .ph , the Philippines Internet country code top level domain p Humanist Party Partido Humanista , Humanist Party in Spanish Paul Harris school, Venezuelan bilingual school in Caracas PH, the Philippines ISO country code Ph digraph , a common digraph that represents the phoneme f voiceless labiodental fricative in phonetics CCSO Nameserver Ph protocol, an early web database search described by RFC 2378 phi letter , the Greek letter Poul Henningsen Danish writer and designer referred to as PH in Denmark The Legend of Zelda Phantom Hourglass , a video game disambig bs PH vor cs PH da PH flertydig de PH es PH desambiguaci n eo PH apartigilo fr PH ko PH it PH disambigua sw PH lv PH noz mju atdal ana lt PH nl Ph ja PH no Ph pl PH pt PH desambigua o sk PH fi Ph th PH vi PH nh h ng ... more details
lowercase title pH meter Image PH Meter.jpg thumb A pH meter A pH meter is an electronic instrument measuring the pH acid ity or base chemistry alkalinity of a liquid though special probes are sometimes used to measure the pH of semi solid substances . A typical pH meter consists of a special measuring probe a glass electrode connected to an electronic meter that measures and displays the pH reading ... PH Meter 01.JPG thumbnail A simple pH meter with its probe immersed in a mildly basic solution. The two knobheads are used to calibrate the instrument. The probe The pH probe measures pH as the activity ... a small voltage about 0.06 volt per pH unit that is measured and displayed as pH units by the meter. For more information about pH probes, see glass electrode Construction glass electrode . The meter The meter circuit is no more than a voltmeter that displays measurements in pH units instead ... typically used with pH meters. The circuit of a simple pH meter usually consists of operational ... converts the small voltage produced by the probe 0.059 volt pH into pH units, which are then offset by seven volts to give a reading on the pH scale. For example At neutral pH pH 7 the voltage at the probe s output is 0 volts. 0 17 7 7. At basic pH, the voltage at the probe ... 10 3 pH units above neutral , 3 0.059 0.18 volts , the output of the meter s amplifier is 0.18 17 7 10. At acid pH, the voltage at the probe s output ranges from 0.41 volts to 0. So for a sample of pH 4 3 pH units below neutral , 3 0.059 0.18 volts ... For very precise work the pH meter should be Calibration calibrated before each measurement. For normal ... be performed with at least two standard buffer solution s that span the range of pH values to be measured. For general purposes buffers at pH 4 and pH 10 are acceptable. The pH meter has one control ..., a three buffer solution calibration is preferred. As pH 7 is essentially, a zero point calibration ... more details
In computational complexity theory , the complexity class PH is the union of all complexity classes in the polynomial hierarchy math mbox PH bigcup k in mathbb N Delta k mbox P math PH was first defined by Larry Stockmeyer . It is a special case of hierarchy of Alternating Turing machine Bounded alternation bounded alternating Turing machine . It is contained in P sup PP sup the class of problems that are decidable by a polynomial time Turing machine with access to a PP complexity class PP oracle machine oracle , P sup P sup by Toda s theorem , and also in PSPACE . PH has a simple logical characterization it is the set of languages expressible by second order logic . PH contains almost all well known complexity classes inside PSPACE in particular, it contains P complexity P , NP complexity NP , and co NP . It even contains probabilistic classes such as Bounded error probabilistic polynomial BPP and RP complexity RP . However, there is some evidence that BQP , the class of problems solvable in polynomial time by a quantum computer , is not contained in PH Aaronson 2010 . P NP if and only if P PH . This may simplify a potential proof of P &ne NP , since it s only necessary to separate P from the more general class PH . References Larry J. Stockmeyer , The polynomial hierarchy , Theoretical Computer Science , Vol. 3 1976 , pp. 1 22. Scott Aaronson , BQP and the Polynomial Hierarchy, ACM STOC 2010 , arxiv 0910.4698 , ECCC 2009 09 104 . CZoo PH P ph ComplexityClasses Category Complexity classes comp sci theory stub es PH clase de complejidad ko PH ja PH ru PH ... more details
Multiple issues expert subject November 2010 refimprove March 2009 inappropriate tone December 2010 pH ... definition of pH is the negative log of the H ion concentration this is why a lower pH value means higher H concentration more acidic soil . Soil pH affects plant nutrient availability by controlling the chemical form of the nutrient. All plants do not have the same pH preference and choosing plants that thrive in the pH of your soil will improve chances of a great garden. However, if you want to grow a plant preferring a pH different from your soil, you can amend your soil to change pH. Image World Soil pH.svg thumb 500px right Global variation in soil pH. font color red Red font acidic soil .... Classification of soil pH ranges The Natural Resources Conservation Service , formerly Soil Conservation Service classifies soil pH ranges as follows ref cite web author Soil Survey Division Staff ... Denomination scope col width 100 pH range Ultra acid 3.5 Extremely acid 3.5 4.4 Very strongly acid ... availability in relation to soil pH citations missing section date November 2010 Nutrients needed ... key components of vitamins. Both macro and trace nutrient availability is controlled by soil pH. Organic ... to soil pH ref Arnold Finck, Kiel 1976 Pflanzenern hrung in Stichworten , p.80, ISBN 3 554 80197 ... N will have the highest concentrations in soil with pH 6 8. Concentrations of available N are less sensitive to pH than concentration of available P. In order for P to be available for plants, soil pH needs to be in the range 6.0 and 7.5. If pH is lower than 6, P starts forming insoluble compounds with iron Fe and aluminium Al and if pH is higher than 7.5 P starts forming insoluble compounds with calcium Ca . Determining pH The world soil pH map shown above indicates large area average pH ranges the only way to know your soil pH is to measure it. Methods of determining pH include ... between thickness of the E and soil pH. E horizons a few feet thick in Florida usually have ... more details
lowercase title pH indicator Acids and Bases A pH indicator is a halochromism halochromic chemical chemical compound compound that is added in small amounts to a solution so that the pH acid ity or Base chemistry basicity of the solution can be determined visually. Hence a pH indicator is a chemical ... on the pH. At 25 Celsius, considered the standard temperature, the pH value of a neutral solution is 7.0. Solutions with a pH value below 7.0 are considered acidic, whereas solutions with pH value ... acid s and amine s, pH indicators find many applications in biology and analytical chemistry. Moreover, pH indicators form one of the three main types of indicator compounds used in chemical analysis ... reaction as the basis of the analysis. Theory In and of themselves, pH indicators are frequently weak acids or bases. The general reaction scheme of a pH indicator can be formulated as follows HInd ... and that connects the color to the pH value. For pH indicators that are weak protolytes, we can write the Henderson Hasselbalch equation for them math textrm pH textrm pK a log frac textrm Ind textrm HInd math The equation, derived from the acidity constant , states that when pH equals the pKa value of the indicator, both species are present in 1 1 ratio. If pH is above the pKa value ... associated with the conjugate base dominates. If pH is below the pKa value, the converse is true. Usually, the color change is not instantaneous at the pKa value, but there is a pH range where a mixture of colors is present. This pH range varies between indicators, but as a rule of thumb, it falls ... is ten times greater than the concentration of the acid, their ratio is 10 1, and consequently the pH ..., the ratio is 1 10 and the pH is pKa &ndash 1. For optimal accuracy, the color difference between the two species should be as clear as possible, and the narrower the pH range of the color ... in other indicators, such as methyl red , both species confer a color. While pH indicators work ... more details
Image PH Lampan 1.jpg right 300px thumb The PH5 lamp designed 1958 The PH lamp s are a series of light fixtures designed by Danish designer and writer Poul Henningsen from 1926 and onwards ref http www.visitdenmark.com uk en gb menu turist inspiration detkulturelledanmark design the ph lamp.htm www.visitdenmark.com ref . The lamp is designed with multiple concentric shades to eliminate visual glare , only emitting reflected light, obscuring the light source. The lamps are still in production today ref http www.louispoulsen.com da Designers Poul 20Henningsen.aspx Louis Poulsen Lighting ref References references Category Lamps Category Danish design Category Industrial designs Category 1926 introductions design stub Denmark stub da PH lampe no PH Lampe ... more details
protein Name Ribonuclease PH caption Structure of the RNase PH hexamer image Crystal structure 1UDN.jpg width 220 HGNCid Symbol RNASEPH AltSymbols EntrezGene OMIM RefSeq UniProt PDB ECnumber 2.7.7.56 Chromosome Arm Band LocusSupplementaryData RNase PH is an 3 5 exoribonuclease and nucleotidyltransferase , present in archaea and bacteria , that is involved in tRNA processing. Contrary to hydrolytic enzymes, it is a phosphorolysis phosphorolytic enzyme, meaning that it uses inorganic phosphate as a cofactor to cleave nucleotide nucleotide bonds, releasing diphosphate nucleotides . The active structure of the proteins is actually a homohexameric complex, consisting of three RNase PH dimers. ref cite journal author Ishii et al. title Crystal structure of the tRNA processing enzyme RNase PH from Aquifex aeolicus journal J Biol Chem. volume 278 pages 32397 404 year 2003 pmid 12746447 doi 10.1074 jbc.M300639200 last2 Nureki first2 O last3 Yokoyama first3 S issue 34 ref RNase PH has homology biology homologues in many other organisms, which are referred to as RNase PH like proteins. When a part of another larger protein has a protein domain domain that is very similar to RNase PH, this is called an RNase PH domain RPD . See also Two highly related exoribonuclease complexes Polynucleotide phosphorylase Exosome complex References references External links http www.rcsb.org pdb explore.do?structureId 1UDN Crystal structure of Aquifex aeolicus RNase PH at the RCSB Protein Data Bank Kinases Category Ribonucleases Category EC 2.7.7 transferase stub fr RNase PH ... more details
Image PH Artichoke lamp.jpg 200px thumb right The PH Artichoke lamp designed 1958 File PH Artichoke BW.jpg 200px thumb right The PH Artichoke lit up. The PH Artichoke Pendant is a designer Light fixture manufactured by Louis Poulsen . It was designed by Poul Henningsen in 1958 . The design centers on a 360 degree glare free light created by 72 leaves, that resemble an Globe artichoke artichoke . The light source or bulb cannot be directly viewed, the light is directed and reflected upon leaves until it illuminates the entire artichoke. A chrome inner diffuser also assists in the proper even reflection of the light source. The light source can be an incandescent bulb high powered halogen lamp halogen or xenon arc lamp xenon , fluorescent lamp fluorescent with the ballast mounted in fixture canopy , or Metal halide lamp metal halide canopy mounted ballast . The metal halide sources are used ... Artichokes.jpg PH Artichoke Pendant has a form similar to an artichoke Image Sphere wireframe.png PH Artichoke Pendant has a form similar to a sphere Image Pinus nigra cone.jpg PH Artichoke Pendant has a form similar to a conifer cone gallery The English name is PH Artichoke artichoke ref Louis Poulsen PH Artichoke http www.louis poulsen.no products product.asp?kmatnr 90145&Lang en&cat 33 ref The original Danish name is PH Kogle conifer cone ref Louis Poulsen PH Kogle http www.louis poulsen.no products product.asp?kmatnr 90145&Lang da&cat 33 ref The Norwegian and German name is PH Kogle ref Louis Poulsen PH Kogle http www.louis poulsen.no products product.asp?kmatnr 90145&Lang no&cat 33 ref PH Zapfen ref Louis Poulsen PH Zapfen http www.louis poulsen.no products product.asp?kmatnr 90145&Lang de&cat 33 ref conifer cone . See also PH lamp References reflist External links http www.louis poulsen.com products product.asp?kmatnr 90145&Lang en&cat 33 Louis Poulsen PH Artichoke Category Lighting brands Category Danish design Category Lamps no PH Kongle ... more details
Orphan date October 2006 Unreferenced stub auto yes date December 2009 All Cell biology cell s contain an intracellular fluid which has a pH value this is known as the intracellular pH pHi . The pHi of cells plays a critical role in their function and close regulation is required for cells to survive. There are numerous mechanisms that can cause pHi to change, including metabolic acid production, leakage of acid across Plasma membrane plasma and organelle membranes and membrane transport process es. The mechanisms that regulate pHi are usually considered to be plasma membrane transporter s of which two main types exist those independent of Bicarbonate HCO sub 3 sub sup &ndash sup and those requiring HCO sub 3 sub sup &ndash sup . The normal intracellular pH is 7.4 .1. Citation needed date March 2009 Intracellular pH is around 7.0 due to acid production. It contains low HCO3 level and thereby at pCO2 above 45 mmHg pH can not be 7.4 but much lower.pH 7.3 in HEK293 cells DEFAULTSORT Intracellular Ph Category Cell biology Biochem stub ... more details
unreferenced date August 2009 PH Games is a tabletop game publisher in India, largely famous for the Revolution game series . It is also well known for other games, such as the Space Travels series , On the Run series , Devastation series and the Legend series , and for making tabletop games on sports such as Cricket and Football. Apart from the unconventional games mentioned above, PH also publishes traditional Roleplaying Role Playing Games, such as Mountain Dweller or The Lost Legacy . PH Games is the largest tabletop game publisher in India, and has so far developed games on three gameplay engine platforms HG game engine HG HG II B3YOND PH Games enjoyed a virtual monopoly, ruling the roost for nearly three years, until finally in 2006, Destruction Games emerged and snatched a huge chunk of the market share . Since then, PH has been constantly on its toes, trying to reclaim its erstwhile credibility and monopoly. PH Games Gameplay Engines HG game engine HG The HG game engine was PH s first gameplay engine. It was characterised by the fact that it incorporated traditional, Turn based strategy turn based , storytelling style gameplay, depending a lot on the game of luck, such as Coin flipping tossing a coin , or throwing the dice. This system also saw some of the greatest titles PH Games is known for, including Devastation Legend On the Run Space Travels Forest Ranger Mountain ... was two years, from mid 2003 to mid 2005. HG II The HG II game engine was PH s second game engine, and it incorporated ..., reaction time , real time storytelling and use of the environment this was heavily publicised by PH ... coming from PH, and this negligence on their part paved the path to the rise of Destruction Games . Some popular games from PH using the HG II gameplay system were On the Run II Revolution Vengeance ... of two years from mid 2005 to mid 2007. B3YOND B3YOND was PH s third gameplay engine, introduced ... 2007, PH is the largest tabletop publisher in India, with 50.93 marketshare. Category Video ... more details
Dentyl pH is a brand of mouthwash . Traditional mouthwash formulations use alcohol or other antimicrobial ingredients to kill bacteria in order to control halitosis . Although Dentyl pH contains Antiseptic anti bacterial agents cetylpyridinium chloride , triclosan , it also contains an oil isopropyl myristate that offers high adhesion to bacteria better than other bacteria or tissue in order to remove bacteria from the mouth. Dentyl pH is as of 2007 one of the top two mouthwash brands in the United Kingdom. ref name ns interview http www.newscientist.com channel opinion mg19526221.600 interview the halitosis guru.html Interview The halitosis guru . New Scientist , 19 September 2007 ref Dentyl pH is sold in Australia, Cyprus, United Kingdom, Finland, France, Ghana, Greece, Iceland, Ireland, Malta, New Zealand , Slovenia, and South Africa. Dentyl has the same acidity as saliva, ref cite web url http www.superdrug.com Dentyl PH DENTYL PH CLOVE ALCOHOL FREE MOUTHWASH 500ML invt 482521 title Dentyl PH Clove Alcohol Free Mouthwash 500ML at Superdrug publisher Superdrug.com date accessdate 2010 08 06 ref so it will not dissolve calcium on teeth, it is also alcohol free. History Dentyl pH was first launched in the UK in 1997, through Fresh Breath Limited, as part of a patients programme that aimed to prevent or treat bad breath , plaque and gum disease . Dentyl pH instantly sparked interest due to its unique formula It consists of two separate, coloured phases a water based phase that contains the antibacterial agent Cetylpyridinium Chloride CPC and an oil based solution with natural essential oils. ref http www.dentylph.com images stories documents The Multiple Benefits of 20Dentyl pH.pdf ref The mouthwash is shaken before use to create a temporary emulsion so that the oils mix ... 2010 08 06 ref In 2007, Dentyl pH released Icy Fresh Mint and Icy Fresh Cherry flavours to be sold ... in 2008, the first flavour of its kind in the market. In 2009, Dentyl pH developed Ultra Cleanse, which ... more details
unreferenced date December 2010 pH partition is the tendency for acid s to accumulate in basic fluid compartment s, and chemical base bases to accumulate in acidic compartments. The reason for this phenomenon is that acids become negatively electric charge d in basic fluids, since they donate a proton . On the other hand, bases become positively electric charged in acid fluids, since they receive a proton. Since electric charge decrease the membrane permeability of substances, once an acid enters a basic fluid and becomes electrically charged, then it cannot escape that compartment with ease and therefore accumulates, and vice versa with bases. DEFAULTSORT Ph Partition Category Acid base chemistry biochemistry stub ... more details
Orphan date February 2009 lowercase Image Gongreensml2.JPG thumb 165px A pH x Duo Water Pipe. pH x is the brand name of a line of borosilicate glass bong water pipes and accessories used for the consumption of smoking mixtures and tobacco products. pH x pipes are typically manufactured using 5.0 mm 1 5 inch thick glass tubing, and house one or more water pipe percolator percolators within their main chamber. They are typically transparent, though rarer colored models have been produced. The pipes utilize a size 19 22 Standard Taper conical ground glass joint in all connecting parts commonly referred to as size 18 mm, 18.8 mm, or 19 mm . pH x is one of the original innovators of the Water pipe percolator percolator ref Heads Magazine, 2006 V.6, I.3 ref , a small additional sub chamber within the main chamber of the water pipe that provides in line smoke water interaction via heat exchanger heat exchange and solvation dissolution . Today, a number of modified Water pipe percolator percolator designs exist amongst various pipe manufacturers, such as LUX, A.D.S., AMG, Blue Dot and RooR . Awards 2002 High Times Cannabis Cup , Glass Cup 3rd Place ref http www.cannabiscupwinners.com hightimescupwinners.htm 2002 Cannabis Cup Winners Hightimes Cannabis Cup Winners page 01 Bot generated title ref References reflist External links http www.phxglass.com pH x glass Official Website. http cannabisculture.com articles 2943.html Article by Cannabis Culture Magazine about the pH x Trinity. Category Drug paraphernalia ... more details
Ph 75 Category Proposed aircraft carriers Category Amphibious warfare vessel classes Category Helicopter ... Category Abandoned military projects of France fr PH 75 porte h licopt res ... more details
page content for recommended layout. Infobox Aircraft Begin name PH please avoid stating manufacturer in this field it s stated two lines below image Image Hall PH 3 1.jpg in the image filename format, no image tags caption Hall PH 3 image caption if it isn t descriptive it should be left blank Infobox ... use but no longer built number built 24 unit cost 170,000 PH 3 ref name USCG PH http www.uscg.mil history WEBAIRCRAFT AC Hall PH2.html Hall PH United States Coast Guard. Retrieved 13 March 2008 ... type The Hall PH was an United States of America American flying boat of the 1930s. A twin engined ... to the Felixstowe F.5 Felixstowe flying boats of the World War I First World War , the PH was purchased ..., Hall received an order for nine production aircraft from the U.S Navy, designated the PH 1 , which ... PH 2 s similar to the PH 1, but with armament removed, and seven PH 3 s with armament re instated ... Delivery of the PH 1 commenced in October 1931, ref name swan navyp254 equipping VP 8 from 1932 ... 1 in 1937. ref name DANAS v2p116 Roberts 2000, p.116. ref Production of the PH recommenced in June 1936 to meet an order for seven PH 2s for the US Coast Guard. ref name swan navyp254 These entered service ... PH The Coast Guard ordered a further seven of an improved version, the PH 3 in 1939, these entering service in 1941. ref name USCG PH The Hall flying boats were used by the Coast Guard for search and rescue ... operations. ref name USCG PH The Coast Guard continued operating the PH 2 and 3 until 1944. ref name USCG PH Variants Image Hall XPH 1 1.jpg thumb right XPH 1 prototype in flight. Note the open pilots canopy XPH 1 Prototype. Two 537 hp 401 kW Wright R 1750 engines. One built. PH 1 Production ... R 1820 86 engines in short Chord aircraft chord Townend ring cowlings. Nine built. PH 2 Version for U.S .... PH 3 Improved version for Coast Guard. Long Chord NACA cowling s. Revised enclosed canopy for pilots ... PH 3 aircraft specifications if you do not understand how to use this template, please ... more details
lowercase A pH balanced cosmetic is any cosmetics cosmetic product that has similar pH value with the target area. category cosmetics health stub ... more details
Unreferenced date February 2007 orphan date November 2009 pH sensitive or pH responsive polymers are materials which will respond to the changes in the pH of the surrounding medium by varying their dimensions. Such materials swell or collapse depending on the pH of their environment. This behaviour is exhibited due to the presence of certain functional groups in the polymer chain. Image PSP.JPG pH sensitive polymer There are two kinds of ph sensitive materials one which have acidic group COOH, SO sub 3 sub H and swell in basic pH, and others which have basic groups NH sub 2 sub and swell in acidic pH. Polyacrylic acid is an example of the former and Chitosan is an example of the latter. The mechanism of response is same for both, just the stimuli vary. The response is triggered due to the presence of ionisable functional groups like COOH, NH sub 2 sub which get ionized and acquire a charge in a certain pH. The polymer chains now have many similarly charged groups which causes repulsion and hence the material expands in dimensions. The opposite happens when pH changes and the functional groups lose their charge hence the repulsion is gone and the material collapses back. These materials are being extensively used in controlled drug delivery systems and biomimetics . DEFAULTSORT Ph Sensitive Polymers Category Smart materials Tech stub ... more details
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