The gas-phase acidities of several α, ω-alkanediols were measured with the equilibrium method in an ion cyclotron resonance spectrometer. The values obtained imply cyclization of the structures via an intramolecular hydrogen bond. The results are in
Proton-bound dimers consisting of two glycerophospholipids with different headgroups were prepared using negative ion electrospray ionization and dissociated in a triple quadrupole mass spectrometer. Analysis of the tandem mass spectra of the dimers
An analysis is made of the possible mechanism of mass transfer in the motion of gas-liquid systems in low-permeability porous media. The mechanism is based on the phenomenon of capillary recondensation.
The sequence and conformational effects on the gas-phase acidities of peptides have been studied by using two pairs of isomeric cysteine-polyglycine peptides, CysGly3,4NH2 and Gly3,4CysNH2. The extended Cooks kinetic method was employed to determine
We determined the gas-phase acidities of two cysteine-polyalanine peptides, HSCA3 and HSCA4, using a triple-quadrupole mass spectrometer through application of the extended kinetic method with full entropy analysis. Five halogenated carboxylic acids
In this paper, an online adaptive model-free tracker is proposed to track single objects in video sequences to deal with real-world tracking challenges like low-resolution, object deformation, occlusion and motion blur. The novelty lies in the constr
Studies were conducted on separation of organic substances with different boiling points and polarity when simultaneously present in water by capillary gas-liquid chromatography on a Kristall 2000 m chromatograph. The effect of the column phase and t
The relative gas-phase acidities were determined for eight flavonoids, applying the kinetic method, by means of electrospray-ion trap mass spectrometry. The experimental acidity order, myricetin > luteolin > quercetin > (±)-taxifolin > kaempferol > a
The gas-phase deprotonation reactions of multiply protonated bovine ubiquitin, insulin chain B, and renin substrate tetradecapeptide ions have been studied in a Fourier transform ion cyclotron resonance mass spectrometer coupled with an external elec
Goll et al. Journal of Cheminformatics 2012, 4(Suppl 1):P8 http://www.jcheminf.com/content/4/S1/P8
Applying the unified pH scale: absolute acidities in the gas phase and anchor points for eleven representative liquid media Sascha K Goll1*, Daniel Himmel1, Ivo Leito2, Ingo Krossing1 From 7th German Conference on Chemoinformatics: 25 CIC-Workshop Goslar, Germany. 6-8 November 2011
The investigations on our recently introduced unified acidity scale  based on the absolute chemical potential of the proton pointed out the inadequateness of the established GA scale. Earlier it was inter alia found that, when trying to correlate pKa with GA values, in several cases the correlation was broken without any sufficient explanation [2,3]. However, the GA does not take into account the pressure dependent speciation in the gas phase. In this contribution we systematically extend the theory of acidity in the gas phase from standard GAs and GBs to the real existing bulk phases . Furthermore we present the rCCC (relaxed COSMO cluster-continuum) model , a quantum chemical solvation model for the calculation of Gibbs solvation energies of the proton with good accuracy. The rCCC values can be used to anchor individual pH scales in different solvents to our universal scale.
Kütt A, Leito I, Kaljurand I, Sooväli L, Vlasov VM, Yagupolskii LM, Koppel IA: A comprehensive self-consistent spectrophotometric acidity scale of neutral Brønsted acids in acetonitrile. J Org Chem 2006, 71:2829-2838. Himmel D, Goll SK, Leito I, Krossing I: to be published. Himmel D, Goll SK, Leito I, Krossing I: Anchor points for the unified Brønsted acidity scale: The rCCC model for the calculation of standard Gibbs energies of proton solvation in eleven representative liquid media. Chem Eur J 2011, 17:5808-5826. doi:10.1186/1758-2946-4-S1-P8 Cite this article as: Goll et al.: Applying the unified pH scale: absolute acidities in the gas phase and anchor points for eleven representative liquid media. Journal of Cheminformatics 2012 4(Suppl 1):P8.
Author details 1 Institute for Inorganic and Analytical Chemistry, Freiburger Materialforschungszentrum FMF and Freiburg Institute for Advanced Studies (FRIAS), Albert-Ludwigs-Universität Freiburg, Freiburg, 79104, Germany. 2 Institute of Chemistry, University of Tartu, Tartu, 50411, Estonia. Published: 1 May 2012 References 1. Himmel D, Goll SK, Leito I, Krossing I: A unified pH scale for all phases. Angew Chem Int Ed Engl 2010, 49:6885-6888. 2. Koppel IA, Koppel J, Pihl V, Leito I, Mishima M, Vlasov VM, Yagupolskii LM, Taft RW: Comparison of Brønsted acidities of neutral CH acids in gas phase and dimethyl sulfoxide. J Chem Soc, Perkin Trans 2 2000, 1125-1133.
* Correspondence: [email protected] 1 Institute for Inorganic and Analytical Chemistry, Freiburger Materialforschungszentrum FMF and Freiburg Institute for Advanced Studies (FRIAS), Albert-Ludwigs-Universität Freiburg, Freiburg, 79104, Germany Full list of author information is available at the end of the article
Publish with ChemistryCentral and every scientist can read your work free of charge Open access provides opportunities to our colleagues in other parts of the globe, by allowing anyone to view the content free of charge. W. Jeffery Hurst, The Hershey Company. available free of charge to the entire scientific community peer reviewed and published immediately upon acceptance cited in PubMed and archived on PubMed Central yours you keep the copyright Submit your manuscript here: http://www.chemistrycentral.com/manuscript/