Recent experiments on the chlorite-iodide-malonic acid-starch reaction in a gel reactor give first evidence of existence symmetry breaking, reaction-diffusion structures predicted by Turing 1952. A five-variable model that describes temporal behavior system is reduced to two-variable model, and its spatial analyzed. Structures have been found with wavelengths are good agreement those observed experimentally. The plays key role binding iodine species, thereby creating necessary difference...

Abstract α‐Lactams have often been postulated as intermediates in numerous processes. The isolation of the first α‐lactam, N‐tert‐butyl‐3‐phenylaziridinone, was accomplished 1962. Since then, further N‐ and C‐3‐substituted α‐lactams synthesized. Most these very reactive compounds undergo easy thermal decomposition; remarkable is relative stability 1,3‐di‐tert‐butylaziridinone, which does not start to decompose below 140°C. α‐lactam ring opened by nucleophilic reagents. — correlation...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTExperimental and modeling study of oscillations in the chlorine dioxide-iodine-malonic acid reactionIstvan Lengyel, Gyula Rabai, Irving R. EpsteinCite this: J. Am. Chem. Soc. 1990, 112, 25, 9104–9110Publication Date (Print):December 1, 1990Publication History Published online1 May 2002Published inissue 1 December 1990https://pubs.acs.org/doi/10.1021/ja00181a011https://doi.org/10.1021/ja00181a011research-articleACS PublicationsRequest reuse...

Transient, symmetry-breaking, spatial patterns were obtained in a closed, gradient-free, aqueous medium containing chlorine dioxide, iodine, malonic acid, and starch at 4 degrees to 5 C. The conditions under which these Turing-type structures appear can be accurately predicted from simple mathematical model of the system. patterns, consist spots, stripes, or both spots require about 25 minutes form remain stationary for 10 30 minutes.

Abstract α‐Lactame wurden seit vielen Jahren als Zwischenstufen bei zahlreichen Prozessen angenommen. Die Isolierung des ersten α‐Lactams, N‐tert.‐Butyl‐3‐phenyl‐aziridinons, gelang 1962. Inzwischen weitere (stets N‐ und C‐3‐substituierte) dargestellt. meisten dieser sehr reaktiven Verbindungen unterliegen leicht der thermischen Zersetzung; auffallend ist die relative Beständigkeit 1,3‐Di‐tert.‐butyl‐aziridinons, das erst 140°C zu zerfallen beginnt. Nucleophile Reagentien öffnen den...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Synthesis and Reactions of an α-Lactam, 1-t-Butyl-3,3-dimethylazirididoneJohn C. Sheehan Istvan. LengyelCite this: J. Am. Chem. Soc. 1964, 86, 7, 1356–1359Publication Date (Print):April 1, 1964Publication History Published online1 May 2002Published inissue 1 April 1964https://pubs.acs.org/doi/10.1021/ja01061a018https://doi.org/10.1021/ja01061a018research-articleACS PublicationsRequest reuse permissionsArticle Views330Altmetric-Citations70LEARN...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTKinetics of iodine hydrolysisIstvan Lengyel, Irving R. Epstein, and Kenneth KustinCite this: Inorg. Chem. 1993, 32, 25, 5880–5882Publication Date (Print):December 1, 1993Publication History Published online1 May 2002Published inissue 1 December 1993https://pubs.acs.org/doi/10.1021/ic00077a036https://doi.org/10.1021/ic00077a036research-articleACS PublicationsRequest reuse permissionsArticle Views802Altmetric-Citations97LEARN ABOUT THESE...

The chlorite-iodide reaction is unusual because it substrate-inhibited and autocatalytic. Because analytically pure ClO2- ion not easily prepared, was generated in situ from the rapid between ClO2 I-. resulting overall multiphasic, consisting of four separable parts. Sequentially, beginning with mixing, these parts are (a) chlorine dioxide-iodide, (b) chlorine(III)-iodide, (c) chlorine(III)-iodine, (d) hypoiodous iodous acid disproportionation reactions. has been studied experimentally by...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSystematic design of chemical oscillators. Part 65. Batch oscillation in the reaction chlorine dioxide with iodine and malonic acidIstvan Lengyel, Gyula Rabai, Irving R. EpsteinCite this: J. Am. Chem. Soc. 1990, 112, 11, 4606–4607Publication Date (Print):May 1, 1990Publication History Published online1 May 2002Published inissue 1 1990https://pubs.acs.org/doi/10.1021/ja00167a103https://doi.org/10.1021/ja00167a103research-articleACS...

In experiments on quasi-two-dimensional Turing structures, patterns form perpendicular to a concentration gradient imposed by the boundary conditions. Using linear stability analysis, with ${\mathrm{ClO}}_{2}$-${\mathrm{I}}_{2}$-MA (malonic acid) reaction as an example, we obtain conditions position along direction and possible three dimensionality of structures. Experiments effects MA starch concentrations structures support theory. Simulations taking into account indicator yield even equal...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Formation of an Isocyanide and a Ketone from α-HaloamideJohn C. Sheehan Istvan. LengyelCite this: J. Am. Chem. Soc. 1964, 86, 4, 746–747Publication Date (Print):February 1, 1964Publication History Published online1 May 2002Published inissue 1 February 1964https://pubs.acs.org/doi/10.1021/ja01058a052https://doi.org/10.1021/ja01058a052research-articleACS PublicationsRequest reuse permissionsArticle Views123Altmetric-Citations39LEARN ABOUT THESE...

Abstract The challenge of devising pathways for organic synthesis remains a central issue in the field medicinal chemistry. Over span six decades, computer-aided planning has given rise to plethora potent tools formulating synthetic routes. Nevertheless, significant expert task still looms: determining appropriate solvent, catalyst, and reagents when provided with set reactants achieve optimize desired product specific step process. Typically, chemists identify key functional groups rings...

Chemical engineers heavily rely on precise knowledge of physicochemical properties to model chemical processes. Despite the growing popularity deep learning, it is only rarely applied for property prediction due data scarcity and limited accuracy compounds in industrially-relevant areas space. Herein, we present a geometric learning framework predicting gas- liquid-phase based novel quantum datasets comprising 124,000 molecules. Our findings reveal that necessity quantum-chemical information...

The dynamical behavior of two coupled cells or reactors is described. are by diffusion, e.g., through a semipermeable membrane, and the chemical reactions initial feed concentrations all species same in cells. Each cell has only single stable steady state absence coupling, system may exhibit multiple states, periodic oscillation, chaos. attractors be either homogeneous (the have equal concentrations) inhomogeneous. Three two-variable kinetic models examined: Brusselator, model chlorine...

Abstract Detailed kinetic models play a crucial role in comprehending and enhancing chemical processes. A cornerstone of these is accurate thermodynamic properties, ensuring fundamental insights into the processes they describe. The prediction thermochemical properties presents an opportunity for machine learning, given challenges associated with their experimental or quantum determination. This study reviews recent advancements predicting gas-phase, liquid-phase, catalytic within modeling....

Abstract The kinetics of the reaction between nitric acid and formaldehyde have been studied by spectrophotometry. is autocatalytic. A two‐step mechanism proposed, which accounts for this behavior describes effect reactant concentrations on characteristics kinetic curves: length induction period, t i , maximum rate, r max nitrous production final product concentration, c f .

High temperature pyrolysis (HTP) is a commercial process to convert methane acetylene. The HTP consists of two reaction zones, followed by quenching zone. In this work, pilot scale was modeled assess the effect amount fuel burned and cracking gas composition on acetylene polycyclic aromatic hydrocarbon (PAH) production. simulated using chemical reactor network, which series ideal reactors. in second zone varied from hexane. propensity feed form vs PAH at given condition determined detailed...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTuring structures in simple chemical reactionsIstvan Lengyel and Irving R. EpsteinCite this: Acc. Chem. Res. 1993, 26, 5, 235–240Publication Date (Print):May 1, 1993Publication History Published online1 May 2002Published inissue 1 1993https://pubs.acs.org/doi/10.1021/ar00029a002https://doi.org/10.1021/ar00029a002research-articleACS PublicationsRequest reuse permissionsArticle Views670Altmetric-Citations28LEARN ABOUT THESE METRICSArticle Views are...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Photochemical Conversion of Phenyl Isocyanate and Diphenyldiazomethane to 2,2-DiphenylindoxylJohn C. Sheehan Istvan LengyelCite this: J. Org. Chem. 1963, 28, 11, 3252–3253Publication Date (Print):November 1, 1963Publication History Published online1 May 2002Published inissue 1 November 1963https://pubs.acs.org/doi/10.1021/jo01046a532https://doi.org/10.1021/jo01046a532research-articleACS PublicationsRequest reuse permissionsArticle...