Results 11 to 20 of about 167,504 (265)
The acid dissociation constants of mellitic acid
CHIMIA, 1977 The acid dissociation constants of mellitic acid were evaluated at 25 °C from potentiometric titrations in aqueous solutions of the constant Na+ molarity 3 M consisting preponderantly of NaClO4. The obtained values are summarized in the table.
Adrian Beutler, Anton Stebler
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Acid dissociation constants of glycopeptides [PDF]
Biochemical Journal, 1977 Glycopeptides containing mainly four amino acid residues in the sequence Asn-Leu-Thr-Ser, with small amounts of additional amino acid residues, were isolated from enzymic hydrolysates of hen's-egg albumin. Heterogeneity of the carbohydrate moiety was confirmed. Acid-base titrations showed that the alpha-amino group has a pKa value of 6.43 at 25 degrees
B M, Austen, R D, Marshall
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The Dissociation Constants of Tetrahydrofolic Acid
Journal of Biological Chemistry, 1966 Six dissociable groups exist in tetrahydrofolic acid in the range H0 -3.0 to pH 14. The assignments in tetrahydrofolic acid by titrimetric and spectrophotometric comparisons with model compounds, p-aminobenzoylglutamic acid and 2-amino-6,7-dimethyl-5,6,7,8-tetrahydro-4-pteridinone, are as follows: acidic ionization of amide, pK' 10.5; N5, pK' 4.82; γ ...
R G, Kallen, W P, Jencks
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Determination of Acid Dissociation Constants of Some 2-(3H) –Benzoxazolone Derivatives by UV–Vis Spectrophotometry [PDF]
Iranian Journal of Chemistry & Chemical EngineeringThe acid dissociation constant values of some 2-(3H)-benzoxazolone derivatives were determined in buffered solutions by using the UV-Vis spectrophotometric method.
Semra Altunterim Erkan +2 more
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The Kinetics of Chitosan Degradation in Organic Acid Solutions
Marine Drugs, 2021 This paper presents a comparative study on chitosan degradation in organic acid solutions according to their different dissociation characteristics. More precisely, the aim of the study was to determine the kinetics of the degradation process depending ...
Dominik Sikorski +2 more
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Measurement of 4-(2-thiazole azo) rososinol acidy constants by means of ultraviolet spectroscopy and chemometrics in water-acetonitrile and water-dioxane binary mixtures [PDF]
شیمی کاربردی روزIn this paper, by combining ultraviolet spectroscopy and Chemometrics method, the acid dissociation constant of 4- (2-thiazole azo) rososinol was measured. The absorption spectra of the 4- (2-thiazole azo) rososinol solution have a large spectral overlap,
Mansoor Namazian +2 more
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Solvent, substituents and pH effects towards the spectral shifts of some highly colored indicators [PDF]
Journal of the Serbian Chemical Society, 2017 The solvatochromic responses of six indicators namely Sudan orange, Alizarin yellow R, Aurin tricarboxylic acid, Alizarin yellow GG, Titan yellow and Eriochrome black-T, dissolved in seven solvents of different polarities, have been measured at room ...
Masoud Mamdouh S. +2 more
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Electrochemistry, 2021 A voltammetric method has been developed for the determination of the acid dissociation constant (pKa) of (RfSO2)2CHR (Rf = perfluoroalkyl), which is a strongly acidic molecule that serves as an acid catalyst.
Akira KOTANI +3 more
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The acid dissociation constant of triethylsilanol in aqueous solution
CHIMIA, 1974 The acid dissociation constant of (C2H5)3SiOH in aqueous solution was evaluated with the aid of a distribution method using CCl4 and an aqueous phase of constant ionic strength as solvents. The experimental results led to a value of pKa = 13.63 (± 0.07)
H. Arm, K. Hochstrasser, P.W. Schindler
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Synthesis and Determination of Acid Dissociation Constants of Bis-Acyl Thiourea Derivatives
Journal of the Turkish Chemical Society, Section A: Chemistry, 2023 N,N'-((dodecane-1,12-diylbis(azanediyl))bis(carbonothioyl))bis(4-nitrobenzamide) 5 and N,N'-((dodecane-1,12-diylbis(azanediyl))bis(carbonothioyl))bis(3-nitrobenzamide) 6 as bis acyl thiourea derivatives were synthesized and their molecular structures ...
Çağla EFEOĞLU +3 more
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