hammett equation in organic chemistry – Hammett

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22.4.2016 · UCI Chem 125 Advanced Organic Chemistry (Spring 2016) Lec 10. Linear Free-Energy Relationships View the complete course: Linear free energy relationship, the Hammett equation and substituent and reaction

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Chemistry 331: Laboratory Manual Environmental Organic Chemistry 3 This experiment investigates the Hammett Equation by measuring the acid dissociation constants of a series of meta and para substituted benzoic acids and phenols. The effect of various substituents on the acid dissociation constants will be determined by measuring the pK

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21.12.2015 · For the Love of Physics – Walter Lewin – May 16, 2011 – Duration: 1:01:26. Lectures by Walter Lewin. They will make you ♥ Physics. Recommended for you

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The Hammett equation in organic chemistry describes a free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a substituent constant and a reaction constant .

33 riviä · * σmeta, σpara = Hammett constants; σI = inductive sigma constant; σv = Charton’s v (size)

GROUP ΣMETA ΣPARA ΣI
H 0.00 0.00 0.00
CH3 -0.07 -0.17 -0.04
C2H5 -0.07 -0.15 -0.05
n-C3H7 -0.07 -0.13 -0.03

Näytä kaikki 33 riviä taulukossa www.wiredchemist.com
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systems of organic reactions in solution is a far distant goal, and at the present time theoretical organic chemistry in general is necessarily semi-empirical and approximate. Nevertheless, in terms of the role which it has played in the broad elucidation of electronic effects and reaction mechanisms, the Hammett equation has been of unparalleled

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THE HAMMETT EQUATION Hammett’s second major contribution to physical-organic chemistry concerned his σρ equation, commonly called the Hammett equation. This concerns the correlation of equi-libria and rates for reactions of substituted aromatic com-pounds. Chemists had long realized that reactions with large

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CHAPTER 1 SUBSTITUENT EFFECTS ON ORGANIC RATES AND EQUILIBRIA I QUALITATIVE DESCRIPTION OF SUBSTITUENT EFFECTS References: 1. Carey & Sundberg Part A, 3rd. ed. p.196 (4th Ed, p. 204) (5th Ed. pp. 297-318)

Overview

This book was first published in 1973. The Hammett equation is used for the elucidation of intramolecular interactions, electronic or steric, and for examination of the influence of substituents on rates or positions of equilibrium of organic reactions.

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The Journal of Organic Chemistry 2003, 68 (20) , 7582-7590. DOI: 10.1021/jo030036k. Luis R. Domingo,, Patricia Pérez, and, Renato Contreras. Electronic Contributions to the σp Parameter of the Hammett Equation. The Journal of Organic Chemistry 2003, 68 (15

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The Hammett equation is one of the most widely applied relations between the structure and reactivity of organic compounds. This equation relates the relative reactivities of the series of di- and poly-substituted benzene derivatives. The various applications of the Hemmett equation to the reactions of heterocyclic compounds are discussed.

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empirical facts of chemistry. One of the more useful generalizations of organic chemistry is the Hammett equation.= This equation correlates the rates of over two hundred reactions with the structure of the reactants. The equation as it stands now is applicable only

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Hammett equation (Hammett relation) (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1119 . Cite as: IUPAC. Compendium of Chemical Terminology, 2nd ed. (the ”Gold Book”). Compiled by A. D. McNaught and A. Wilkinson. Blackwell

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Physical Organic Chemistry Thermodynamics and kinetics Outline: Isotope effects • see section 8.1 of A&D – experimental approach – primary isotope effect – secondary isotope effect – equilibrium isotope effect – solvent isotope effect – heavy atom isotope effects 2

Organic Chemistry-I: 3:0: Stereochemistry and conformational analysis. Methods of deducing organic reaction mechanisms, Hammond postulate, Curtin-Hammett principle, linear free energy relationships; Hammett equation; kinetic isotope effects.

Hammett equation The Hammett equation in organic chemistry describes a free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta-and para-substituents to each other with just two parameters: a substituent constant and a reaction constant .

Unit 4: Free Energy Relationships . The Hammett Equation. The correlation of reaction equilibria and rates with changes in structure is a major goal of chemistry. In organic chemistry, the change in an equilibrium constant, K, or a rate constant,

26-6A The Hammett Equation. If we compare the acid strengths \(\left( K_a \right)\) of a series of substituted benzoic acids with the strength of benzoic acid itself (Table 26-4), we see that there are considerable variations with the nature of the substituent and its ring position, ortho, meta, or para.

The Hammett plot is commonly invoked in organic chemistry to reason about the plausibility (or implausibility) of various reaction mechanisms. The vertical axis is essentially the logarithm of an equilibrium constant (or rate constant) measured relative to a hydrogen functional group, which I

Reaction dynamics, Hammond postulate Linear free energy relationship, Hammett equation. Week 8. Yukawa Tsuno equation, Swain-Lupton equation, Grunwald–Winstein equation, Taft equation Curtin-Hammett principle, Organic Chemistry, Volume 2: Stereochemistry and The Chemistry of Natural Products, Chapter 2, 5th Ed, Pearson Education India

1.4.2019 · A Theoretical Formulation of the Hammett. Equation. Gordon A. Gallup. UNL, [email protected] The Hammett equation relates observed changes in equilibrium or rate constants to The Hammett Equation relates the relative magnitude of the equilibrium The Hammett equation in organic chemistry describes a linear free-energy relationship relating ..

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Download Citation | Class Projects in Physical Organic Chemistry: The Hammett Equation | This paper provides a brief introduction to the Hammett equation. A laboratory experiment is described that requires students to determine the pKa | Find, read and cite all the research you need on ResearchGate

Physical Organic Chemistry Louis P. Hammett Snippet view – 1940. Physical organic chemistry conjugate acid decomposition decrease derivatives dielectric constant effect electrolyte electron electrophilic enol entropy equation equilibrium constant ester ethanol ether ethyl formation free energy H H H halogen Hammett hydrolysis hydroxyl

Linear free energy relationships 1. Linear Free Energy Relationship: The Hammett Equation Dr. Satyajit Dey Post Graduate Organic Chemistry Course (4th semester) Dr. Satyajit Dey Department of Chemistry Tamralipta Mahavidyalaya Tamluk Midnapore (East) 2. Syllabus Semester – IV (Organic Special) 3. 1.

Substituent Constants
Hammettequation

27.10.2017 · Persamaan Hammett juga tidak berlaku pada rantai turunan alifatik karena pelintiran rantai karbon dapat menimbulkan aksi sterik (halangan sterik). Pengaruh dari substituen pada cincin benzena terhadap keasaman asam benzoat ditunjukkan melalui nilai

Course content. The course deals with fundamental principles and methods used in physical and mechanistically organic chemistry: (i) Description of molecules (includes reactive intermediates as radicals, carbenes, carbocations and carbanions) based

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LOUIS P. HAMMETT was one of the founders of physical-organic chemistry, and a major contributor to it. Together with Arthur Lapworth and Christopher Ingold he created a new branch of chemistry, a new discipline. The ideas and principles of physical-organic chemistry changed the world’s teaching and

The plot of the Hammett equation is typically seen as being linear, with either a positive or negative slope correlating to the value of rho. However, nonlinearity emerges in the Hammett plot when a substituent affects the rate of reaction or changes the rate-determining step or reaction mechanism of the reaction.

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Validity of the Hammett equation for isolated molecules: b Institute of Organic Chemistry, Prague Institute of Chemical Technology, Praha 6, Czech Republic Abstract. Atomic and electronic energies of 27 3- and 4-substituted benzonitriles and of their protonated forms

Physical Organic Chemistry – authorSTREAM Presentation. Physical Organic The Hammett equation in organic chemistry describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para- substituents to How Email Boost Organic Traffic. By:

extended Hammett equation +\beta \ \sigma _{R}+h\] The equation may be applied to systems for which the inclusion of further terms to represent other effects, e.g. steric, is appropriate. Source: PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1114 Cite as:

Hammett equation. Quite the same Wikipedia. Just better. Live Statistics. English Articles. Improved in 24 Hours. Added in 24 Hours. Languages. Recent.

Acidities of 19 meta- and para-substituted ethynylbenzenes were calculated at the B3LYP/6-311+G(d,p) level and correlated within the framework of the Hammett equation with the calculated acidities of equally substituted benzoic acids. The substituent effects were decomposed in terms of isodesmic reactions in

The linear relationship fit well in the Hammett Equation. The Hammett equation in organic chemistry describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para- substituents to each other with just two parameters: Learn how and when to

Hammett equation The Hammett equation in organic chemistry describes a free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta-and para-substituents to each other with just two parameters: a substituent constant and a reaction constant .

The Vis absorption spectra were investigated in four protic solvents (water, 2,2,2‐trifluoroethanol, ethylene glycol, and methanol). The substituent effects were then quantified using the Hammett equation which correlates the MLCT absorption wavenumbers with the Hammett constant (σ x).

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Hammett Plot – Free download as PDF File (.pdf), Text File (.txt) or read online for free. hóa học nâng cao

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simply from the ionization of organic acids in solution, can frequently predict successfully equilibrium and rate constants for a variety of families of reactions in solu- tion. Almost every kind of organic reaction has been treated via the Hammett equation, or its extended form. The literature is so voluminous and extensive that there

Hammett Equation

The Hammett equation in organic chemistry describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a substituent constant and a reaction constant.

The Hammett equation in organic chemistry describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a

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Organic Chemistry, 5th Edition L. G. Wade, Jr. A DESCRIPTION OF STRUCTURES AN ENERGIES OF STARTING MATERIALS AND PRODUCTS OF A REACTION AS WELL AS • In the equation DGo = DHo – TDSo the entropy value is often small. => Bond

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Department of Chemistry, University of Warsaw, 02093 Warsaw, ul. Pasteura 1, Poland Received November 11, 1983 The paper is an overview of the application of the concept of linear free energy relationships (LFER), most notably through the Hammett equation, to investigations of reversible organic elec-trochemical reactions in aprotic solvents.

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1 IFM/ Kemi Stefan Svensson 20020423 Problems in Physical-Organic Chemistry Part 1: General problems 1.1 Predict the most stable conformation for each of the following molecules and explain

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CHM 311: Physical Organic Chemistry Problem Set 1 correlated by the Hammett equation. For the ionization equilibrium given below, calculate G and S at 298 K. Draw a Hammett plot for this equilibrium and calculate . Comment on the sign and magnitude of . 5.

The Hammett acidity function is used in fields such as physical organic chemistry for the study of acid-catalyzed reactions, because some of these reactions use acids in

THE HAMMETT EQUATION Download The Hammett Equation ebook PDF or Read Online books in PDF, EPUB, and Mobi Format. Click Download or Read Online button to THE HAMMETT EQUATION book pdf for free now. In this book my aim has been describe the fundamental principles of organic chemistry.

the hammett equation Download the hammett equation or read online books in PDF, EPUB, Tuebl, and Mobi Format. Click Download or Read Online button to get the hammett equation book now. In this book my aim has been describe the fundamental principles of organic chemistry.

The Hammett equation in substituents to each other with just two parameters: a substituent constant and a reaction constant . This equation was developed and published by Louis Plack Hammett in 1937 as a follow up to qualitative observations in a 1935 publication . The basic idea is that for any two reactions with two aromatic reactants only

The Hammett Equation by C.D Johnson.docx – Free download as Word Doc (.doc / .docx), PDF File (.pdf), Text File (.txt) or read online for free. The Hammett equation in physical organic chemistry

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Reaction intermediates in organic chemistry — The “big picture”1 John Andraos Abstract: An overview of the discovery of reaction intermediates and associated concepts in physical organic chemis-try is presented. Particular attention is paid to chronology of ideas, frequency of

An equation used in organic chemistry to predict reactions for aromatic compounds. Open image in new window This is a preview of subscription content, log in to check access.

AbeBooks.com: The Hammett Equation (Cambridge Texts in Chemistry and Biochemistry) (9780521201384) by C. D. Johnson and a great selection of similar New, Used and Collectible Books available now at great prices.

Ces valeurs sont ensuite injectées dans l’équation de Hammett, ce qui permet, puisque le paramètre ρ est fixé à 1, d’obtenir les paramètres σ p. La répétition de la séquence en plaçant les substituants en position méta, permet d’obtenir les valeurs de paramètres σ m.

The emergence of putative Hammett equation in mid 1930s was a boon to physical-organic chemists to elucidate the reaction mechanisms of several organic reactions. Based on the concept of this equation several hundreds of papers have emerged in chemical literature in the last century on the effect of structure, on reactivity, and very few on

Reaction dynamics, Hammond postulate Linear free energy relationship, Hammett equation. Week 8. Yukawa Tsuno equation, Swain-Lupton equation, Grunwald–Winstein equation, Taft equation Curtin-Hammett principle, clearing every concept in organic chemistry from basic and giving assignments to us. Keep it up sir.

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Linear Free Energy Relationships (LFERs): Applying the Hammett Equation to a Series of Substituted Benzoic Acids Background: A linear free-energy relationship is said to exist if ‘the same series of changes in conditions affects the rate or equilibrium of a second reaction in exactly the same way as the first’. Hammett was the first to

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The application of the Hammett equation to the solvolysis of benzyl tosylates Jay Kazuo Kochi Iowa State College Follow this and additional works at:https://lib.dr.iastate.edu/rtd Part of theOrganic Chemistry Commons, and thePhysical Chemistry Commons theoretical organic chemistry.

The Hammett acidity function (H 0) is a measure of acidity that is used for very concentrated solutions of strong acids, including superacids. It was proposed by the physical organic chemist Louis Plack Hammett and is the best-known acidity function used to extend the measure of Brønsted–Lowry acidity beyond the dilute aqueous solutions for

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physical-organic chemistry for the last 35-40 years to undergraduate and graduate students, we understand this particular aspect of mechanistic application of Taft equation is either ignored or not appropriately stressed while teaching applications of Taft equation in a physical -organic chemistry graduate class -room.

Read ”Plurilinear improvement of the Hammett equation, Journal of Physical Organic Chemistry” on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.

Hammett, who spent his entire career at Columbia, regarded himself as a physical chemist (he wrote two other texts, ”Solutions of Electrolytes” and ”Introduction to Physical Chemistry”) who found his research outlet in studying organic compounds and their reactions. Among his many honors was the National Medal of Science (1968).

Teoria. Hammett-yhtälö on nimetty sen 1937 keksineen Louis Plack Hammettin mukaan, joka havaitsi jo 1935 p/m-areenien happovakioiden ja reaktionopeusvakioiden välillä olevan lineaarinen yhteys. Hän vertaili muun muassa substituoitujen bentsoehappojen ja etikkahappojen etyyliesterien emäksellä tehtyjen hydrolyysien log 10 k -arvoja

Application of Hammett equation to structure-reactivity correlations of a “localized reaction site” in elucidating the reaction mechanisms of several organic reactions is a very well-knownphenomenon in physical-organic chemistry class-room of senior undergraduate and graduate level students. This is a testament of purely chemical phenomena.

1. We have shown the applicability of the Hammett equation to the basicity constants of phosphines. 2. We have calculated the values for the constant a for p-C8H17, cyclo-C6H11, and CH2CH2CN

Range of validity of the Hammett equation: Acidity of substituted ethynylbenzenes. Characteristic deviations from the Hammett equation were found for para-substituents, in the design and development novel molecules has considerable interest in many industrial and synthetic reactions in organic chemistry.

The Hammett equation in organic chemistry describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a

L. Hammett defines physical organic chemistry Pauling’s Nature of the Chemical Bond catalytic cracking of petroleum Lewis and Bronsted acid-base theories organolithium compounds are made Bohr atomic orbital shell model H. Staudinger describes polymers A. Fleming discovers penicillin 1920 : G.N. Lewis defines a covalent bond Haber synthesis of

Best Organic Chemistry Books for Undergraduate: 1. Cheletropic reactions, hydrogenation of unsaturated systems, ambident nucleophile, Hammett equation and Taft equation have been introduced in appropriate chapters.

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Reaction Intermediates in Organic Chemistry: the ”Big Picture” John Andraos Department of Chemistry, York University, Toronto, ON M3J 1P3 [email protected] FAX: 416-736-5936 Supplementary Material Table S1. List of important concepts in physical organic chemistry by year of discovery.a Year Concept in physical organic chemistry (scientists)b

Physical organic chemistry is the study of organic chemistry using methods of physical chemistry such as chemical equilibrium, chemical kinetics, thermochemistry, and quantum chemistry. In the present article an attempt is made to correlate the nature of heterolysis five different free radical type nitroxyl adducts using Hammett’s Liner Free Energy Relationships.

This paper provides a brief introduction to the Hammett equation. A laboratory experiment is described that requires students to determine the pK a of three para-substituted phenols through the use of UV-spectroscopy. A student’s individual data are combined with other students’ data to provide a class set.

This chapter discusses the common functional groups of organic compounds with consideration of the chemical in Comprehensive Heterocyclic Chemistry III, 2008. 11.19.4 Following successful application of the Hammett equation in homogeneous catalysis, several publications appeared about the direct utilization of the Hammett

Hammett equation (or Hammett relation) Hybrid orbitals are often used in organic chemistry to describe the bonding molecules containing tetrahedral (sp 3), trigonal (sp 2), and digonal (sp) atoms. hydration. Addition of water or of the elements of water (i.e. H and OH) to a molecular entity.

Esta obra contiene una traducción derivada de Hammett equation de Wikipedia en inglés; concretamente de publicada por bajo la Licencia de documentación libre de GNU y la Licencia Creative Commons Atribución-CompartirIgual 3.0 Unported. «Hammett equation (Hammett relation) – IUPAC Goldbook» (en inglés)

organic chemistry-ii – linear free energy relationship, the hammett equation and substituent and reaction constants the hammett equation and substituent and reaction constants organic chemistry-ii – linear free energy relationship, the hammett equation and substituent and reaction constants posted by dr a.c.v. ramakumar.

The linear free-energy relationship: Hammett equation, Taft equation, Hammett-Brown equation and Swain-Scott equation are introduced in this section The acid/base theory in organic chemistry: the fundamental concepts of acid and base, acidity function, super acid, factors of acidity and basicity, acid or base catalysts, the principles and applications of the hard-soft-acid-base (HSAB) theory

Correlation of structure with reactivity – linear free energy relationships Hammett equation – interpretation of substitutent and reaction constants – ?, ?+, ? -, polar and steric substitutent constants L.P. Hammett, Physical Organic Chemistry, 2nd edition, McGraw Hill, New York, 1970;

Interactions between large organic ions of opposite charge G.I. Mukhayer and S.S. Davis 1977 Journal of Colloid and Interface Science 61 582 Crossref. THE APPLICATION OF THE HAMMETT EQUATION TO CYCLOPHOSPHAZENES Marvin Charton and Barbara I. Charton 1977 Phosphorous and Sulfur and the Related Elements 3 367 Crossref

Buy The Hammett Equation (Cambridge Texts in Chemistry and Biochemistry) New Ed by C. D. Johnson (ISBN: 9780521299701) from Amazon’s Book Store. Everyday low

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Example Problems. Applications of Hammett Equation: Substituent and Reaction Constants. Predict the pKa for the following phenols using the appropriate substituent constants, a pKa for unsubstituted phenol of 9.90 and a ρ-value of 2.25.

The Hammett acidity function is a measure of acidity that is used for very concentrated solutions of strong acids, including superacids. In such solutions, simple approximations such as the Henderson-Hasselbalch equation are no longer valid due to the variations of the activity coefficients in highly concentrated solutions.

Hammett is considered one of the founding fathers of physical organic chemistry in the United States. He is best known for his work with strong acids that led to the Hammett acidity function, his work with linear free energy relationships that led to the Hammett equation, and his 1940 book, Physical

mchem/bsc chem shc4002 tut3—hammett equation q1. under strongly alkaline conditions (methoxide ion) hcl is eliminated from 2chloro-2-methyl-1-phenylpropane to

View Notes – Hammett Equation1 from CHEMISTRY Organic ch at IIT Kanpur. Hammett Correlations and Their Applications in Elucidating Reaction Mechanism Stoltz Group Literature Seminar Eric

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Organic Chemistry Lecture Outline Chapter 16: Chemistry of Benzene: Electrophilic Aromatic Substitution C. SUBSTITUENT EFFECTS ON pKa of IONIZABLE FUNCTIONAL GROUPS OF AROMATIC RINGS 1. The Hammett Equation a. The Hammett equation is a mathematical formula which relates substituent effects (electron donating

Physical Organic Chemistry Louis P. Hammett Snippet view – 1940. Physical organic chemistry conjugate Consequently constant contains converted decrease depends derivatives determined displacement effect electron energy equation equilibrium ester ethyl fact formation function given greater halide halogen hydrogen hydrogen bromide hydrolysis

The Taft equation is a linear free energy relationship (LFER) used in physical organic chemistry in the study of reaction mechanisms and in the development of quantitative structure–activity relationships for organic compounds. It was developed by Robert W. Taft in 1952 as a modification to the Hammett equation.

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