A5075764388- Atmospheric chemistry and aerosols
- Advanced Chemical Physics Studies
- Cholinesterase and Neurodegenerative Diseases
- Neuroscience and Neuropharmacology Research
- Spectroscopy and Quantum Chemical Studies
- Catalytic Processes in Materials Science
- Mass Spectrometry Techniques and Applications
- Free Radicals and Antioxidants
- Spectroscopy and Laser Applications
- Molecular Sensors and Ion Detection
- Enzyme function and inhibition
- Photochemistry and Electron Transfer Studies
- Atmospheric Ozone and Climate
- Advanced Combustion Engine Technologies
- Drug Transport and Resistance Mechanisms
- Computational Drug Discovery Methods
- Protein Structure and Dynamics
- Catalysis and Oxidation Reactions
- Molecular spectroscopy and chirality
- Synthesis and Reactivity of Sulfur-Containing Compounds
- Chemical Synthesis and Analysis
- Synthesis and Characterization of Heterocyclic Compounds
- Liver Disease Diagnosis and Treatment
- Parallel Computing and Optimization Techniques
- Chemical Reaction Mechanisms
HUN-REN Research Centre for Natural Sciences
2004-2017
Institute of Organic Chemistry
2012-2017
Hungarian Academy of Sciences
1996-2014
Institute of Materials and Environmental Chemistry
2000-2012
University of America
1992-2001
Catholic University of America
1992-2001
The kinetics of the reactions C2H3 + H2 → H C2H4 (1) and CH3 CH4 (2) have been studied in temperature ranges 499−947 K (reaction 1) 646−1104 2) He densities (6−18) × 1016 atoms cm-3 by laser photolysis/photoionization mass spectrometry. Rate constants were determined time-resolved experiments as a function temperature. Ethylene was detected primary product reaction 1. Within above experimental rate can be represented Arrhenius expressions k1 = (3.42 ± 0.35) 10-12 exp(−(4179 67 K)/T) cm3...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTWeak collision effects in the reaction ethyl radical .dblarw. ethene + hydrogenY. Feng, J. T. Niiranen, A. Bencsura, V. D. Knyazev, Gutman, and W. TsangCite this: Phys. Chem. 1993, 97, 4, 871–880Publication Date (Print):January 1, 1993Publication History Published online1 May 2002Published inissue 1 January 1993https://pubs.acs.org/doi/10.1021/j100106a012https://doi.org/10.1021/j100106a012research-articleACS PublicationsRequest reuse...
Networks are increasingly recognized as important building blocks of various systems in nature and society. Water is known to possess an extended hydrogen bond network, which the individual bonds broken sub-picosecond range still network structure remains intact. We investigated compared topological properties liquid water methanol at temperatures using concepts derived within framework graph theory (neighbour number cycle size distribution, distribution local cyclic bonding coefficients,...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTKinetics of the unimolecular decomposition isopropyl: weak collision effects in helium, argon, and nitrogenP. W. Seakins, S. H. Robertson, M. J. Pilling, I. R. Slagle, G. Gmurczyk, A. Bencsura, D. Gutman, TsangCite this: Phys. Chem. 1993, 97, 17, 4450–4458Publication Date (Print):April 1, 1993Publication History Published online1 May 2002Published inissue 1 April...
Kinetics and mechanism of the reaction OH with CH3C(O)CH3 have been studied by discharge-flow experiments CCSD(T) quantum chemical computations. In experiments, rate coefficient for overall reaction, + → products (1), branching ratio specific channel CH2C(O)CH3 H2O (1a) determined to be k1 = (1.04 ± 0.03) × 1011 cm3 mol−1 s−1 Γ1a k1a/k1 0.50 0.04, respectively (T 298 K). Two different pathways characterized ab initio calculations. Both H atom abstraction addition CO group found occur through...
Molecular mechanics and dynamics combined with semiempirical calculations were carried out for purposes of comparison the active site characteristics AChE, trypsin, chymotrypsin as probed by their diastereomeric adducts 2-(3,3-dimethylbutyl) methylphosphonofluoridate (soman), methylphosphonate monoester anions, tetravalent carbonyl intermediates reactions natural substrates in each case. Glu199 is a key residue electrostatic catalytic mechanism removal leaving group, possibly acting an...
Molecular dynamics (MD) simulations using CHARMM were performed for the solution structures of pentacoordinate and tetracoordinate PSCS PRCS adducts Torpedo californica (Tc) acetylcholinesterase (AChE) formed with 2-(3,3-dimethylbutyl) methylphosphonofluoridate (soman) to assess molecular origins stereoselectivity phosphonylation. MD also carried out transients in soman-inhibited trypsin evaluate differences mode operation two enzymes. Parameters phosphonate fragments constructed from...
Molecular dynamics was used to analyze energy transfer rates between matrix and guest molecules in matrix-assisted laser desorption allowing for a large number of internal degrees freedom. The effect initial temperature jump on equilibration times limiting temperatures has been studied model system comprising pyridine-3-carboxylic acid leucine enkephalin (Tyr-Gly-Gly-Phe-Leu) molecule. It appears that the depend jump. 900 K leads incomplete desorption, whereas at 1500 complete formation an...
The product yield of the electron-impact dissociation methane has been studied with a combination three theoretical methods: R-matrix theory to determine electronically inelastic collisional excitation cross sections, high-level electronic structure methods excited states energies and derivative couplings, trajectory surface hopping (TSH) calculations branching in give CH(3), CH(2), CH. involve lowest 24 excited-state potential surfaces methane, up ionization energy. According calculations,...
Quasiclassical trajectory calculations have been performed for the H + H′X(v) → X HH′ abstraction and XH H′ (X = Cl, F) exchange reactions of vibrationally excited diatomic reactant at a wide collision energy range extending to ultracold temperatures. Vibrational excitation increases cross sections significantly. If vibrational is larger than height potential barrier reaction, reactive diverge very low energies, similarly capture reactions. The divergence quenched by rotational but returns...
Besides aiding digestion, bile salts are important signal molecules exhibiting a regulatory role in metabolic processes. Human ileal acid binding protein (I-BABP) is an intracellular carrier of the epithelial cells distal small intestine and has key enterohepatic circulation salts. Positive cooperativity combined with site selectivity glycocholate glycochenodeoxycholate, two most abundant human body, make I-BABP unique member family lipid proteins. Solution NMR structure ternary complex...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTKinetics and Thermochemistry of the Reaction 1-Chloroethyl Radical with Molecular OxygenVadim D. Knyazev, Akos Bencsura, Ilia A. Dubinsky, David Gutman, Carl F. Melius, Selim M. SenkanCite this: J. Phys. Chem. 1995, 99, 1, 230–238Publication Date (Print):January 1995Publication History Published online1 May 2002Published inissue 1 January 1995https://pubs.acs.org/doi/10.1021/j100001a036https://doi.org/10.1021/j100001a036research-articleACS...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEnantioselective and Reversible Inhibition of Trypsin .alpha.-Chymotrypsin by Phosphonate EstersQinjian Zhao, Ildiko M. Kovach, Akos Bencsura, Adonia PapathanassiuCite this: Biochemistry 1994, 33, 26, 8128–8138Publication Date (Print):July 1, 1994Publication History Published online1 May 2002Published inissue 1 July 1994https://pubs.acs.org/doi/10.1021/bi00192a018https://doi.org/10.1021/bi00192a018research-articleACS PublicationsRequest reuse...
Ambient level of gamma -aminobutyric acid (GABA), the major inhibitory neurotransmitter brain is mediated by neuronal and glial GABA transporters (GATs), members sodium chloride ion-dependent solute carrier family. The transporter subtype (GAT-1) has already been proven to be target for antiepileptic drug Tiagabine. However, druggability GAT-2 GAT-3 yet established. Recent advances in structure elucidation a bacterial orthologue leucine complex with different substrates substantiate homology...
Abstract Rate constants for the unimolecular decomposition of CH 3 CO have been obtained as a function temperature (420 ‐ 500 K) and helium density (3 18 · 10 16 atom cm −3 ), conditions which are in second order region fall‐off curve. An Arrhenius expression low‐pressure limit rate constant was from results, k 1 ±(He) = (6.7 ± 1.8) −9 exp[(‐6921 126 K)/ T ] molecule −1 s . Using Master Equation formalism to calculate values , set two energy parameters needed calculations, E Δ ) down...
The kinetics of the unimolecular decomposition FCO radical has been studied experimentally in a heated tubular flow reactor coupled to photoionization mass spectrometer. Rate constants for were determined time-resolved experiments as function temperature (951−1051 K) and bath gas density ((6−12) × 1016 molecules cm-3) two gasesHe N2. rate are low-pressure limit under conditions can be described by following expressions: k°1(He) = 10-8.74±0.28 exp(−(14169 ± 653 K)/T) cm3 molecule-1 s-1 (from...
The channels connecting the active site of acetylcholinesterase (AChE) to protein exterior were mapped by computational techniques in order find potential exit routes for charged reaction products. 3.9% total volume AChE monomer is hollow space and over 50% void located center; it partitioned into three chambers, a deep entry channel, below wide channel slightly positive region ideally suitable negatively fragments small chamber above Trp 84 Met 83 . latter serve as gates departure...