At pH values greater than the pKa of the carboxylic acid group ( mean for the 20 common amino acids is about 2. 2, see the table of amino acid structures above ), the negative carboxylate ion predominates.

At pH values lower than the pKa of the α-ammonium group ( mean for the 20 common α-amino acids is about 9. 4 ), the nitrogen is predominantly protonated as a positively charged α-ammonium group.

At pH values between the two pKa values, the zwitterion predominates, but coexists in dynamic equilibrium with small amounts of net negative and net positive ions.

At a pH below their pI, proteins carry a net positive charge ; above their pI they carry a net negative charge.

At pH 4. 8, the interior of the lysosomes is acidic compared to the slightly alkaline cytosol ( pH 7. 2 ).

At high pH, sarin decomposes rapidly to nontoxic phosphonic acid derivatives.

At 25 ° C, considered the standard temperature, the pH value of a neutral solution is 7. 0.

At the same time, the separating part of the gel also has a pH value in which the buffer ions on average carry a greater charge, causing them to " outrun " the SDS-covered proteins and eliminate the ion gradient and thereby the stacking effect.

At the mean pH of the laryngopharynx ( pH

At high temperatures, the rate of collagen loss will be accelerated and extreme pH can cause collagen swelling and accelerated hydrolysis.

At a pH equal to the protonated base's pKa, the protonated ( ionized ) and unprotonated ( unionized ) forms of the molecule exist in equimolar amounts but only the unprotonated base diffuses readily across cell membranes.

At a lower pH, further chlorination occurs.

At a pH of 7, the enzymes that were present from the stomach are no longer active.

At all pH values other than their isoelectric point, proteins will be charged.

At pH < 5. 89 ( pH < pK < sub > 1 </ sub >) the hydrogen chromate ion is predominant in dilute solution but the dichromate ion is predominant in more concentrated solutions.

At pH 12-13, any ammonium ion in the sample is converted to ammonia gas and is ultimately detected by the electrode.

At neutral pH, the dye absorbs red light most strongly and transmits blue light.

At low pH, the dye absorbs ultraviolet and blue light most strongly and appears yellow in solution.

At pH 7, glucose exists in solution in cyclic hemiacetal form as 63. 6 % β-D-glucopyranose and 36. 4 % α-D-glucopyranose, the proportion of linear and furanose form being negligible.

At the neutral pH outside of the cell the E2 envelope protein covers the E1 protein.

At high temperatures, above 24-27 ° C, the solvent melts and the salt dissociates, reversibly reacts with the weak acid and increases the pH.

At such critical moments predispositions favorable to human dignity most obviously `` pay off ''.

At the time Alex arrived he was engaged in some sort of intimate communication with the hen, who had settled herself on the nest most peacefully after the occurrences of the morning.

At the Westminster KC Dog Show in Madison Square Garden, New York on the second day, the Finals of the Junior Class brought out the most competitive competition in the history of this Class.

At one time, to most Americans, unless they were fortunate enough to live near a body of navigable water, boats were considered the sole concern of fishermen, rich people, and the United States Navy.

At its most ecstatic moments, husband and wife are elevated far above worldly cares.

At the peak of her fame, fans looking for images of Kournikova made her name one of the most common search strings on Google.

* 1969 – At a zebra crossing in London, photographer Iain Macmillan takes the photo that becomes the cover of the Beatles album Abbey Road, one of the most famous album covers in recording history.

At the same time, the most western island of the Juan Fernández Islands was renamed Alejandro Selkirk Island although Selkirk probably never saw that island ( 97 miles west ).

At the age of 25, he was elected a member of the French Academy of Sciences, France's most elite scientific society, for an essay on street lighting and in recognition of his earlier research.

At the end of the game, all players liquidate their stock in order to determine which player has the most money.

At speaker meetings one or two members tell their stories, while discussion meetings allocate the most time for general discussion.

At the time it was being developed, a full, reliable connection-oriented protocol like TCP was considered to be too expensive to implement for most of the intended uses of AppleTalk.

At the turn of the 19th century, immigrants from Naples and Genoa opened the first pizza bars, though Spanish residents subsequently owned most of the pizza businesses.

At this time, Anubis was the most important god of the dead but he was replaced during the Middle Kingdom by Osiris.

At pHs lower than 5 most fish eggs will not hatch and lower pHs can kill adult fish.

At ambient conditions, berkelium assumes its most stable α form which has a hexagonal symmetry, space group P6 < sub > 3 </ sub >/ mmc, lattice parameters of 341 pm and 1107 pm.

At its most recent meeting, November 27 – December 1, 2006, the Conference of the Parties of the Basel Agreement focused on issues of electronic waste and the dismantling of ships.

At the time of his retirement from the England team in 1970, he was the nation's most capped player, having turned out 106 times at the highest level.

At the end of 1131, the kingdoms of France, England, Germany, Castile, and Aragon supported Innocent ; however, most of Italy, southern France, and Sicily, with the patriarchs of Constantinople, Antioch, and Jerusalem, supported Anacletus.

At what point during the war Teach joined the fighting is, in keeping with the record of most of his life before he became a pirate, unknown.

At the time of his death, he was one of the most acclaimed scientists in Europe.

At most dances, no special outfits are worn, but " peasant skirts " or other full, lightweight skirts are popular, as these have a very pretty effect when swinging or twirling and some dancers find them more comfortable to dance in than pants.

At the most basic level, this involves establishing what form of currency the country may have, whether a fiat currency, gold-backed currency ( disallowed for countries with membership of the International Monetary Fund ), currency board or a currency union.

At the moment, most community colleges award qualifications up to Level 3 in the Malaysian Qualifications Framework ( Certificate 3 ) in both the Skills sector ( Sijil Kemahiran Malaysia or the Malaysian Skills Certificate ) as well as the Vocational and Training sector but the number of community colleges that are starting to award Level 4 qualifications ( Diploma ) are increasing.

At the passage of the most important decrees, not more than sixty prelates were present.