(n.) An oxide of a nonmetallic body or an organic radical, capable of forming an acid by uniting with the elements of water; -- so called because it may be formed from an acid by the abstraction of water.
Example Sentences:
(1) The 1-0-methylalduronic-acidmethylesters, obtained by the methanolysis of the polysaccharides, are reduced with boronhydrid to the corresponding methyl glycosides; there are split with acid to the aldoses, which are converted in pyridine with hydroxylamine to the aldoximes and than with acetic anhydride to the aldonitrilacetates, which can be separated by gaschromatography without difficulty.
(2) Several aminoacyl-tRNA synthetases are herein shown to catalyze the AMP----ADP and ADP----ATP exchange reactions (in the absence of tRNAs) by utilizing a transfer of the gamma-phosphate of ATP to reactive AMP and ADP intermediates that are probably the mixed anhydrides of the nucleotide and the corresponding amino acid.
(3) The aza analogue (RS)-3-hydroxy-2,5-pyrrolidinedione-3-acetic acid (6) of the five-membered citric anhydride (2) was prepared in the sequence citric acid----2-phenyl-1,3-dioxolan-4-one-5,5-diacetic acid (1)----citric acid beta-amide (3)----6 and used to resolve ambiguities in the mechanism of the citrate synthase reaction.
(4) The method involves solvent extraction of the compounds from plasma, derivatization with pentafluoropropionic anhydride and subsequent separation on a 3% OV-17 column.
(5) The 6alpha- and 6beta-testosterone derivatives were attached to BSA via a mixed anhydride coupling employing tributylamine and i minus-butylchlorocarbonate.
(6) It is concluded that the side product generated during the reaction of Fmoc-chloride with glutamic acid which is used for analysis of the latter is the N-protected internal anhydride and not the pyroglutamate as reported in the literature.
(7) When a larger excess of ethoxyformic anhydride was used for the lipase reaction, 2.8 histidine residues were ethoxyformylated and characterised as His-354, His-156 and His-75, which resulted in an 85% inhibition of the tributyrylglycerol hydrolysis by the enzyme.
(8) The three compounds, which all possess carboxylic acid group, were converted into their hexafluoro-2-propyl esters with hexafluoropropan-2-ol-pentafluoropropionic anhydride as reagent.
(9) New light-curable adhesive opaque resins were prepared using 4-methacryloxyethyl trimellitate anhydride (4-META), triethylene glycol dimethacrylate (TEGDMA), di (methacryloxyethyl) trimethylhexamethylene diurethane (UDMA) and titanium dioxide.
(10) Five microliters of acetic anhydride was added to the serum to convert all 5-ASA to Ac-5-ASA.
(11) The equilibrium constant for formation of the anhydride from the thil ester of enzyme and methyl 3-mercaptopropionate is 75 times larger than the equilibrium constant of 2.2 for the formation of N,O-diacetylhydroxylamine from acetohydroxamic acid and acetyl-CoA.
(12) For the quantitative determination of sulfolipids having long sugar chains, it is necessary to treat thin-layer chromatography plates with acetic anhydride before color development.
(13) We have changed the net charge to -6 by acylation with acetylcitric anhydride (a new acylating agent); this anionic derivative forms tetrameric helix at neutral pH, without salt, and at relatively low concentration, conditions under which the cationic MLT does not become helical.
(14) A sensitive potentiometric monitoring method was developed that permits the continuous measurement of the disolution profiles of methyl vinyl ether-maleic anhydride-acid copolymers and salt derivatives.
(15) Thromboxane B2 (TxB2) was coupled with beta-D-galactosidase by mixed anhydride reaction.
(16) To obtain a volatile histidine derivative it has been found necessary to add an antioxidant and to heat samples with ethoxyformic anhydride prior to injection.
(17) Bronchial provocation studies using alcoholic-saline solutions of phthalic anhydride and phthalic anhydride dust resulted in immediate airway obstruction.
(18) Acylation of glutamate dehydrogenase with ethoxyformic anhydride at pH6.1 led to the modification of three histidine residues with a corresponding loss of half the original activity.
(19) The extract of plasma or urine was treated with diazomethane followed by trifluoroacetic anhydride to convert I and II into their methyl ester trifluoroacetyl derivatives.
(20) The reaction was monitored by capillary gas chromatography after derivatization by trifluoroacetic anhydride.
Anhydrite
Definition:
(n.) A mineral of a white or a slightly bluish color, usually massive. It is anhydrous sulphate of lime, and differs from gypsum in not containing water (whence the name).
Example Sentences:
(1) The second shrinkage between 300 degrees C and 400 degrees C was due to the transformation of soluble anhydrite to insoluble anhydrite.
(2) However, the SEM observations of the fractured surface of compacts suggested that the second shrinkage corresponded to the grain growth of insoluble anhydrite.
(3) The third shrinkage beginning at the temperature range 700 degrees C approximately 800 degrees C is considered to be related to the sintering of insoluble anhydrite.
(4) The sintering kinetics of insoluble anhydrite were studied by measuring the isothermal shrinkage of compacts of insoluble anhydrite powders in air.
(5) The dehydration of gypsum (calcium sulfate dihydrate) was not completed until the initial stage of this large shrinkage was reached, but the phase transition of calcium sulfate anhydrite (III-CaSO4 to II-CaSO4) was the major cause for the large shrinkage.