This document summarizes a study that determined the self-exchange electron transfer rate constant for the vanadium(IV/V) couple in the natural product amavadin. Key findings include:
1) The self-exchange rate constant for amavadin was determined to be 1 x 106 dm3 mol-1 s-1 at 25°C, representing the first unambiguous example for a vanadium(IV/V) couple.
2) Amavadin's structure, with an eight-coordinate non-oxo vanadium center and lack of "yl" type oxygens, allows unambiguous determination of the self-exchange rate constant without complications from other pathways or geometry changes.
3) Direct measurement using
Mannich Synthesis Under Ionic Liquid [Et3NH][HSO4] CatalysisIOSRJAC
Ionic liquid [Et3NH][HSO4] was found to be a particularly efficient catalyst for the synthesis of β- amino carbonyl pyrimidines through the Mannich condensation reaction of substituted pyrimidin-2(1H)-ones, cyclohexanone and 4-fluro/chlorobenzaldehyde under ultrasonic irradiation at room temperature. The present methodology offers several advantages such as excellent yields, simple procedure and mild conditions.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This chapter of the general chemistry textbook discusses solubility and complex ion equilibria. It covers topics such as the solubility product constant Ksp, the common ion effect, limitations of Ksp, criteria for precipitation, fractional precipitation, effects of pH on solubility, and equilibria involving complex ions. It also describes the process of qualitative cation analysis using selective precipitation of cations in different solubility groups.
Synthesis and characterization of the mixed ligand complexesTaghreed Al-Noor
This paper presents the synthesis and study of some new mixed-ligands complexes
containing anthranilic acid and amino acid L-alanine (Ala) with some metals. The resulting
products were found to be solid crystalline complexes which have been characterized by using
(FT-IR,UV-Vis) spectra , melting point, molar conductivity , chloride ion content were also
determin by (mohr method) and determination the percentage of the metal in the complexes by
(AAS).The proposed structure of the complexes was suggested using program , Chem Office
3D(2004) .The general formula have been given for the prepared complexes :
[M(A)(Ala)]. nH2O n= 0,2
AH = Anthranilic acid = C7H7NO2 AlaH = alanine = C3H7NO2
Anthranilate ion = C7H6NO2- Ala- = Alanin ate ion = C3H6NO2-
M(II): Mn(II) ,Fe(II),Co(II) , Ni(II) , Cu(II) , Zn(II) and Cd
This document contains an example chemistry question from an exam with multiple parts asking about reaction rates and mechanisms. It provides sample solutions for: (1) writing rate equations and explaining how temperature affects reaction rate; (2) calculating time for a reaction to reach a concentration using half-life; (3) explaining how changing concentrations affects rate; (4) drawing an enthalpy profile diagram for a reaction mechanism; (5) explaining observations of precipitation reactions; and (6) describing chemical tests to distinguish between compounds involving addition of reagents and observation of results. Diagrams and chemical equations are included as part of the responses.
This document discusses the hydrolysis of 2-bromopropane. It finds the reaction exhibits both first-order and second-order kinetics, indicating contributions from SN1 and SN2 pathways. The percentage of the reaction proceeding by the SN2 pathway increases with higher hydroxide ion concentration and the activation energy is lower for SN2 than SN1, showing SN2 is favored. Two possible organic byproducts are an alkene from elimination and another alcohol from further reaction of the main product.
Mannich Synthesis Under Ionic Liquid [Et3NH][HSO4] CatalysisIOSRJAC
Ionic liquid [Et3NH][HSO4] was found to be a particularly efficient catalyst for the synthesis of β- amino carbonyl pyrimidines through the Mannich condensation reaction of substituted pyrimidin-2(1H)-ones, cyclohexanone and 4-fluro/chlorobenzaldehyde under ultrasonic irradiation at room temperature. The present methodology offers several advantages such as excellent yields, simple procedure and mild conditions.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This chapter of the general chemistry textbook discusses solubility and complex ion equilibria. It covers topics such as the solubility product constant Ksp, the common ion effect, limitations of Ksp, criteria for precipitation, fractional precipitation, effects of pH on solubility, and equilibria involving complex ions. It also describes the process of qualitative cation analysis using selective precipitation of cations in different solubility groups.
Synthesis and characterization of the mixed ligand complexesTaghreed Al-Noor
This paper presents the synthesis and study of some new mixed-ligands complexes
containing anthranilic acid and amino acid L-alanine (Ala) with some metals. The resulting
products were found to be solid crystalline complexes which have been characterized by using
(FT-IR,UV-Vis) spectra , melting point, molar conductivity , chloride ion content were also
determin by (mohr method) and determination the percentage of the metal in the complexes by
(AAS).The proposed structure of the complexes was suggested using program , Chem Office
3D(2004) .The general formula have been given for the prepared complexes :
[M(A)(Ala)]. nH2O n= 0,2
AH = Anthranilic acid = C7H7NO2 AlaH = alanine = C3H7NO2
Anthranilate ion = C7H6NO2- Ala- = Alanin ate ion = C3H6NO2-
M(II): Mn(II) ,Fe(II),Co(II) , Ni(II) , Cu(II) , Zn(II) and Cd
This document contains an example chemistry question from an exam with multiple parts asking about reaction rates and mechanisms. It provides sample solutions for: (1) writing rate equations and explaining how temperature affects reaction rate; (2) calculating time for a reaction to reach a concentration using half-life; (3) explaining how changing concentrations affects rate; (4) drawing an enthalpy profile diagram for a reaction mechanism; (5) explaining observations of precipitation reactions; and (6) describing chemical tests to distinguish between compounds involving addition of reagents and observation of results. Diagrams and chemical equations are included as part of the responses.
This document discusses the hydrolysis of 2-bromopropane. It finds the reaction exhibits both first-order and second-order kinetics, indicating contributions from SN1 and SN2 pathways. The percentage of the reaction proceeding by the SN2 pathway increases with higher hydroxide ion concentration and the activation energy is lower for SN2 than SN1, showing SN2 is favored. Two possible organic byproducts are an alkene from elimination and another alcohol from further reaction of the main product.
Kinetics of Ruthenium(III) Catalyzed and Uncatalyzed Oxidation of Monoethanol...Ratnakaram Venkata Nadh
Kinetics of uncatalyzed and ruthenium(III) catalyzed oxidation of monoethanolamine by N-bromosuccinimide
(NBS) has been studied in an aqueous acetic acid medium in the presence of sodium acetate
and perchloric acid, respectively. In the uncatalyzed oxidation the kinetic orders are: the first order in NBS,
a fractional order in the substrate. The rate of the reaction increased with an increase in the sodium acetate
concentration and decreased with an increase in the perchloric acid concentration. This indicates that free
amine molecules are the reactive species. Addition of halide ions results in a decrease in the kinetic rate,
which is noteworthy. Both in absence and presence of a catalyst, a decrease in the dielectric constant of the
medium decreases the kinetic rate pointing out that these are dipole—dipole reactions. A relatively higher
oxidation state of ruthenium i.e., Ru(V) was found to be the active species in Ru(III) catalyzed reactions. A
suitable mechanism consistent with the observations has been proposed and a rate law has been derived to
explain the kinetic orders.
The document provides examples for calculating the Ksp (solubility product constant) of various ionic compounds given their molar solubility in water. It first explains the general process: writing the dissolution reaction, writing the Ksp expression, inserting concentrations based on molar ratios, and calculating the value. Several examples are then worked through step-by-step, calculating Ksp values from molar solubilities for compounds such as silver bromide, calcium fluoride, and mercury(I) bromide. The document also discusses calculating Ksp from solubilities provided in grams per 100mL by first converting to molar solubility. More examples demonstrate this process for nickel sulfide, magnesium fluoride, and manganese(II) i
This document summarizes a study on the leaching behavior of cobaltous oxide (CoO) and cobalto-cobaltic oxide (Co3O4) in ammonia and acid solutions. The dissolution of cobaltous oxide was found to be chemically controlled, with apparent activation energies of 54.0 kJ/mol and 56.5 kJ/mol in ammonia and acid solutions, respectively. The dissolution rate of cobalto-cobaltic oxide in ammonia-ammonium carbonate was very slow at low temperatures. At higher temperatures, less than 2 x 10-5 mol/dm3 of cobalt remained in solution due to precipitation of cobalt carbonate and cobalto-cobalt
This document contains a chemistry test with 60 multiple choice questions covering topics in chapters 7-11 of book 1, including solutions, colligative properties, thermochemistry, thermodynamics, equilibrium, kinetics, electrochemistry, and catalysis. The questions assess understanding of key concepts such as Raoult's law, heat of reaction, activation energy, redox reactions, reaction rate laws, and enzyme catalysis. An answer key is provided with the correct response for each question.
IRJET- Kinetic Study of the Reaction of 5-Chlorosalicyaldehyde with M- To...IRJET Journal
This document reports on a kinetic study of the reaction between 5-chlorosalicylaldehyde and m-toluidine to form a Schiff base. The reaction was studied spectrophotometrically in ethanol solution at temperatures ranging from 303 to 318 K. The reaction was found to be first order with respect to both 5-chlorosalicylaldehyde and m-toluidine. The rate of reaction increased with increasing temperature. Thermodynamic parameters including activation energy, enthalpy, entropy and free energy were calculated from the temperature dependence of the reaction rate.
Haloalkanes and haloarenes notes by rawat sirRawat DA Greatt
This document contains notes on haloalkanes and haloarenes. It discusses the nature of the C-X bond in alkyl halides and how haloalkanes and haloarenes are prepared through various reactions like Sandmeyer's reaction, Wurtz reaction, and electrophilic aromatic substitution. The physical properties of haloalkanes and haloarenes are described, including their solubility, density, polarity, and boiling points. The document also outlines several chemical properties and reactions of haloalkanes like nucleophilic substitution, elimination, and reactions with metals. Important reactions for conversions of functional groups are also listed.
Совместная статья с проф. Коттоном про статистическое разупорядочение фрагментов в кластерных соединениях (первое соединение с разупорядочением и по катиону и по аниону)
Removal of cadmium from aqueous solution using cobalt silicate precipitation ...IJSIT Editor
This document discusses the removal of cadmium from aqueous solutions using cobalt silicate precipitation tubes (CoSPT) as an adsorbent. CoSPT was synthesized through a "silica garden" process and found to be an effective adsorbent for cadmium. Batch adsorption studies were conducted to determine the effect of contact time, adsorbent dose, initial cadmium concentration, temperature, and pH. Experimental data fit the Langmuir and Freundlich isotherm models well. Kinetic studies showed that the pseudo-second order model provided the best fit. The maximum adsorption capacity of CoSPT for cadmium was estimated to be 319 mg/g based on
This document describes an unprecedented C-methylation reaction at the 2-position of 4-chromanone-2-carboxylates using the Corey–Chaykovsky reagent (dimethylsulfoxonium methylide, DIMSOY). Treatment of various 4-chromanone-2-carboxylates with DIMSOY results in good yields of the corresponding 2-methylated products, rather than the expected epoxide formation. Computational calculations provide evidence that the reaction proceeds through cisoid addition of DIMSOY to the carbonyl, formation of a betaine intermediate, and methyl transfer to C2 via a transition state, enabled by the basic nature of DIMSO
1. The document contains an unsolved chemistry practice test with 43 multiple choice questions and answers related to topics like atomic structure, chemical bonding, thermodynamics, kinetics and equilibrium.
2. The questions cover concepts such as Bohr model, de Broglie wavelength, Lewis structures, IUPAC naming, acid-base reactions, salt solubility, electrolysis, redox reactions, colligative properties, rate laws, free energy and entropy changes.
3. The document tests understanding of fundamental chemistry principles as well as the ability to apply these principles to solve quantitative problems.
1. When a tertiary alkyl halide reacts with a sodium alkoxide, an elimination reaction occurs rather than a substitution reaction. Alkenes are formed instead of ethers.
2. According to Bohr's theory of the hydrogen atom, the radius of an electron's orbit is directly proportional to the ratio of the principal quantum number squared and the atomic number.
3. Isomers (B) and (C) have identical shapes, which can be described as planar.
This study investigates the corrosion inhibition of iron by six mono-azo dye derivatives (MAD_1-6) in 2M HNO3 and 2M NaOH solutions using experimental and computational methods. Gravimetric, thermometric, UV-Vis spectrophotometric, and electrochemical polarization techniques were used to determine inhibition efficiencies experimentally. Density functional theory calculations and molecular dynamics simulations were performed to calculate quantum chemical parameters and binding energies on the Fe(110) surface. Theoretical data agreed well with experimental inhibition efficiencies, with MAD_1 and MAD_6 showing the best inhibition in acidic and alkaline solutions, respectively.
The document outlines various addition reactions to alkenes and alkynes, including addition of HX, H2O, SO4, halogens, and oxidation reactions. It discusses important concepts like Markovnikov's rule, regioselectivity, stereochemistry including anti-Markovnikov additions from hydroboration-oxidation. A variety of methods are covered for converting alkenes and alkynes to alcohols, diols, dihalides, and cleaving carbon-carbon double or triple bonds.
This document is a summer project report submitted by Sayantan Mahapatra to his research supervisor Prof. E. Arunan at the Indian Institute of Science. The project examines chlorine bond distances in weakly bonded complexes between various chlorine bond donors (D=F, Cl, CN, NC, OH, SCl, CCH) and acceptors (A=CH3, NH3, C2H2, C2H4, H2) using computational methods. Key findings include defining explicit chlorine bond radii for each donor based on atoms-in-molecules analysis and observing trends in radii, stability, and charges on chlorine atoms between different donors.
The document appears to be a chemistry exam containing 30 multiple choice questions covering various topics in chemistry. Some of the questions test conceptual understanding of topics like acid strength, coordination complexes, gas laws, and organic reaction mechanisms. Other questions require calculations involving quantities like pH, molality, amounts of substances in chemical reactions. The exam is assessing students' mastery of core chemistry concepts and principles as well as their problem solving abilities through multiple choice questions.
This document is a 35 question practice test for the AIEEE chemistry exam that covers topics like organic chemistry reactions, inorganic compounds, thermodynamics, and quantum mechanics. It provides the questions, answers, and a note that the key and any updates can be accessed online. The test was prepared by V. Aditya vardhan as practice for competitive exams beyond just the AIEEE.
This document summarizes research on the molar volume and rheology of anionic surfactants in non-aqueous media. Specifically, it examines zinc hexanoate and decanoate as mono-alkanoates and butanedioate and hexanedioate as dialkanoates in a benzene-methanol mixture. The apparent molar volume and critical micelle concentration were determined from density measurements. Viscosity measurements provided data on fluidity and rheology. The molar volume and critical micelle concentration increased with longer alkanoate chain length, while fluidity decreased.
Navigating Customer Lifetime Value Conundrumgregmgaffney
This document provides a three-phase framework for calculating and using customer lifetime value (CLV).
1) The first phase is to define key parameters like the analysis units, available data, and objectives.
2) The second phase is to develop the CLV model by building assumptions, examining existing customer models, and choosing a modeling methodology.
3) The third phase is to deploy the CLV model by testing it, integrating it into decision systems, and applying it to resource allocation and other marketing activities.
The framework is intended to help organizations navigate the complex process of CLV analysis and deployment.
Lenders Compliance Group is a full-service mortgage risk management firm specializing exclusively in outsourced mortgage compliance services for banks and non-banks. It offers a comprehensive suite of mortgage compliance services including audits, reviews, analytics, training, licensing assistance, and default management. Lenders Compliance Group aims to help clients achieve and maintain compliance with various federal, state, and investor regulations and standards.
Phoenix Fashion Week is the leading fashion industry event in Arizona. Our Mission is to bridge national and international designers with retailers, boutiques, fashionistas, and the fashion media, throughout the world.
The 4 day fashion event will showcase Holiday 2015 and Spring 2016 collections with 27 designer runway shows, various trunk sales, statewide retail events, fashionable workshops and fabulous after parties. Phoenix Fashion Week is dedicated to developing the Arizona fashion industry through fashionable Humanity- benefiting Breast Cancer research with our FASHIONABLY PINK Celebrity Runway Show – in 2014 by Schumacher European Ltd. Mercedes Benz.
Our state-wide educational fashion seminars and workshops led by top industry experts are now on a year-round schedule.
October 2015 - www.phoenixfashionweek.com Founded 2005: Incorporated 2008 15 established designers, 12 emerging, and 10+ accessory designers present prêt-a-porter, evening, resort collections, luxury sportswear, celebrity designer, high fashion swimwear, and fashionable accessories.
2013/2014 Highlights: TIME Magazine Feature - 55 TV Spots over 3.0 Million Impressions
Kinetics of Ruthenium(III) Catalyzed and Uncatalyzed Oxidation of Monoethanol...Ratnakaram Venkata Nadh
Kinetics of uncatalyzed and ruthenium(III) catalyzed oxidation of monoethanolamine by N-bromosuccinimide
(NBS) has been studied in an aqueous acetic acid medium in the presence of sodium acetate
and perchloric acid, respectively. In the uncatalyzed oxidation the kinetic orders are: the first order in NBS,
a fractional order in the substrate. The rate of the reaction increased with an increase in the sodium acetate
concentration and decreased with an increase in the perchloric acid concentration. This indicates that free
amine molecules are the reactive species. Addition of halide ions results in a decrease in the kinetic rate,
which is noteworthy. Both in absence and presence of a catalyst, a decrease in the dielectric constant of the
medium decreases the kinetic rate pointing out that these are dipole—dipole reactions. A relatively higher
oxidation state of ruthenium i.e., Ru(V) was found to be the active species in Ru(III) catalyzed reactions. A
suitable mechanism consistent with the observations has been proposed and a rate law has been derived to
explain the kinetic orders.
The document provides examples for calculating the Ksp (solubility product constant) of various ionic compounds given their molar solubility in water. It first explains the general process: writing the dissolution reaction, writing the Ksp expression, inserting concentrations based on molar ratios, and calculating the value. Several examples are then worked through step-by-step, calculating Ksp values from molar solubilities for compounds such as silver bromide, calcium fluoride, and mercury(I) bromide. The document also discusses calculating Ksp from solubilities provided in grams per 100mL by first converting to molar solubility. More examples demonstrate this process for nickel sulfide, magnesium fluoride, and manganese(II) i
This document summarizes a study on the leaching behavior of cobaltous oxide (CoO) and cobalto-cobaltic oxide (Co3O4) in ammonia and acid solutions. The dissolution of cobaltous oxide was found to be chemically controlled, with apparent activation energies of 54.0 kJ/mol and 56.5 kJ/mol in ammonia and acid solutions, respectively. The dissolution rate of cobalto-cobaltic oxide in ammonia-ammonium carbonate was very slow at low temperatures. At higher temperatures, less than 2 x 10-5 mol/dm3 of cobalt remained in solution due to precipitation of cobalt carbonate and cobalto-cobalt
This document contains a chemistry test with 60 multiple choice questions covering topics in chapters 7-11 of book 1, including solutions, colligative properties, thermochemistry, thermodynamics, equilibrium, kinetics, electrochemistry, and catalysis. The questions assess understanding of key concepts such as Raoult's law, heat of reaction, activation energy, redox reactions, reaction rate laws, and enzyme catalysis. An answer key is provided with the correct response for each question.
IRJET- Kinetic Study of the Reaction of 5-Chlorosalicyaldehyde with M- To...IRJET Journal
This document reports on a kinetic study of the reaction between 5-chlorosalicylaldehyde and m-toluidine to form a Schiff base. The reaction was studied spectrophotometrically in ethanol solution at temperatures ranging from 303 to 318 K. The reaction was found to be first order with respect to both 5-chlorosalicylaldehyde and m-toluidine. The rate of reaction increased with increasing temperature. Thermodynamic parameters including activation energy, enthalpy, entropy and free energy were calculated from the temperature dependence of the reaction rate.
Haloalkanes and haloarenes notes by rawat sirRawat DA Greatt
This document contains notes on haloalkanes and haloarenes. It discusses the nature of the C-X bond in alkyl halides and how haloalkanes and haloarenes are prepared through various reactions like Sandmeyer's reaction, Wurtz reaction, and electrophilic aromatic substitution. The physical properties of haloalkanes and haloarenes are described, including their solubility, density, polarity, and boiling points. The document also outlines several chemical properties and reactions of haloalkanes like nucleophilic substitution, elimination, and reactions with metals. Important reactions for conversions of functional groups are also listed.
Совместная статья с проф. Коттоном про статистическое разупорядочение фрагментов в кластерных соединениях (первое соединение с разупорядочением и по катиону и по аниону)
Removal of cadmium from aqueous solution using cobalt silicate precipitation ...IJSIT Editor
This document discusses the removal of cadmium from aqueous solutions using cobalt silicate precipitation tubes (CoSPT) as an adsorbent. CoSPT was synthesized through a "silica garden" process and found to be an effective adsorbent for cadmium. Batch adsorption studies were conducted to determine the effect of contact time, adsorbent dose, initial cadmium concentration, temperature, and pH. Experimental data fit the Langmuir and Freundlich isotherm models well. Kinetic studies showed that the pseudo-second order model provided the best fit. The maximum adsorption capacity of CoSPT for cadmium was estimated to be 319 mg/g based on
This document describes an unprecedented C-methylation reaction at the 2-position of 4-chromanone-2-carboxylates using the Corey–Chaykovsky reagent (dimethylsulfoxonium methylide, DIMSOY). Treatment of various 4-chromanone-2-carboxylates with DIMSOY results in good yields of the corresponding 2-methylated products, rather than the expected epoxide formation. Computational calculations provide evidence that the reaction proceeds through cisoid addition of DIMSOY to the carbonyl, formation of a betaine intermediate, and methyl transfer to C2 via a transition state, enabled by the basic nature of DIMSO
1. The document contains an unsolved chemistry practice test with 43 multiple choice questions and answers related to topics like atomic structure, chemical bonding, thermodynamics, kinetics and equilibrium.
2. The questions cover concepts such as Bohr model, de Broglie wavelength, Lewis structures, IUPAC naming, acid-base reactions, salt solubility, electrolysis, redox reactions, colligative properties, rate laws, free energy and entropy changes.
3. The document tests understanding of fundamental chemistry principles as well as the ability to apply these principles to solve quantitative problems.
1. When a tertiary alkyl halide reacts with a sodium alkoxide, an elimination reaction occurs rather than a substitution reaction. Alkenes are formed instead of ethers.
2. According to Bohr's theory of the hydrogen atom, the radius of an electron's orbit is directly proportional to the ratio of the principal quantum number squared and the atomic number.
3. Isomers (B) and (C) have identical shapes, which can be described as planar.
This study investigates the corrosion inhibition of iron by six mono-azo dye derivatives (MAD_1-6) in 2M HNO3 and 2M NaOH solutions using experimental and computational methods. Gravimetric, thermometric, UV-Vis spectrophotometric, and electrochemical polarization techniques were used to determine inhibition efficiencies experimentally. Density functional theory calculations and molecular dynamics simulations were performed to calculate quantum chemical parameters and binding energies on the Fe(110) surface. Theoretical data agreed well with experimental inhibition efficiencies, with MAD_1 and MAD_6 showing the best inhibition in acidic and alkaline solutions, respectively.
The document outlines various addition reactions to alkenes and alkynes, including addition of HX, H2O, SO4, halogens, and oxidation reactions. It discusses important concepts like Markovnikov's rule, regioselectivity, stereochemistry including anti-Markovnikov additions from hydroboration-oxidation. A variety of methods are covered for converting alkenes and alkynes to alcohols, diols, dihalides, and cleaving carbon-carbon double or triple bonds.
This document is a summer project report submitted by Sayantan Mahapatra to his research supervisor Prof. E. Arunan at the Indian Institute of Science. The project examines chlorine bond distances in weakly bonded complexes between various chlorine bond donors (D=F, Cl, CN, NC, OH, SCl, CCH) and acceptors (A=CH3, NH3, C2H2, C2H4, H2) using computational methods. Key findings include defining explicit chlorine bond radii for each donor based on atoms-in-molecules analysis and observing trends in radii, stability, and charges on chlorine atoms between different donors.
The document appears to be a chemistry exam containing 30 multiple choice questions covering various topics in chemistry. Some of the questions test conceptual understanding of topics like acid strength, coordination complexes, gas laws, and organic reaction mechanisms. Other questions require calculations involving quantities like pH, molality, amounts of substances in chemical reactions. The exam is assessing students' mastery of core chemistry concepts and principles as well as their problem solving abilities through multiple choice questions.
This document is a 35 question practice test for the AIEEE chemistry exam that covers topics like organic chemistry reactions, inorganic compounds, thermodynamics, and quantum mechanics. It provides the questions, answers, and a note that the key and any updates can be accessed online. The test was prepared by V. Aditya vardhan as practice for competitive exams beyond just the AIEEE.
This document summarizes research on the molar volume and rheology of anionic surfactants in non-aqueous media. Specifically, it examines zinc hexanoate and decanoate as mono-alkanoates and butanedioate and hexanedioate as dialkanoates in a benzene-methanol mixture. The apparent molar volume and critical micelle concentration were determined from density measurements. Viscosity measurements provided data on fluidity and rheology. The molar volume and critical micelle concentration increased with longer alkanoate chain length, while fluidity decreased.
Navigating Customer Lifetime Value Conundrumgregmgaffney
This document provides a three-phase framework for calculating and using customer lifetime value (CLV).
1) The first phase is to define key parameters like the analysis units, available data, and objectives.
2) The second phase is to develop the CLV model by building assumptions, examining existing customer models, and choosing a modeling methodology.
3) The third phase is to deploy the CLV model by testing it, integrating it into decision systems, and applying it to resource allocation and other marketing activities.
The framework is intended to help organizations navigate the complex process of CLV analysis and deployment.
Lenders Compliance Group is a full-service mortgage risk management firm specializing exclusively in outsourced mortgage compliance services for banks and non-banks. It offers a comprehensive suite of mortgage compliance services including audits, reviews, analytics, training, licensing assistance, and default management. Lenders Compliance Group aims to help clients achieve and maintain compliance with various federal, state, and investor regulations and standards.
Phoenix Fashion Week is the leading fashion industry event in Arizona. Our Mission is to bridge national and international designers with retailers, boutiques, fashionistas, and the fashion media, throughout the world.
The 4 day fashion event will showcase Holiday 2015 and Spring 2016 collections with 27 designer runway shows, various trunk sales, statewide retail events, fashionable workshops and fabulous after parties. Phoenix Fashion Week is dedicated to developing the Arizona fashion industry through fashionable Humanity- benefiting Breast Cancer research with our FASHIONABLY PINK Celebrity Runway Show – in 2014 by Schumacher European Ltd. Mercedes Benz.
Our state-wide educational fashion seminars and workshops led by top industry experts are now on a year-round schedule.
October 2015 - www.phoenixfashionweek.com Founded 2005: Incorporated 2008 15 established designers, 12 emerging, and 10+ accessory designers present prêt-a-porter, evening, resort collections, luxury sportswear, celebrity designer, high fashion swimwear, and fashionable accessories.
2013/2014 Highlights: TIME Magazine Feature - 55 TV Spots over 3.0 Million Impressions
Tale of Three Economies: US, China & indiaSantosh Pathak
The document summarizes similarities and differences between the economies of the US, China, and India, which together represent a large portion of the global economy and population. Some key points:
- All three countries have large, diverse populations and economies but foreign firms often treat them as homogeneous markets, leading to high failure rates.
- They each have a combination of wealthy, middle class, and poor consumers. However, their financial systems are at different stages of development and their firms differ in levels of globalization.
- The US has an older and wealthier population while India has a young and growing middle class. China's population is aging but still largely middle class.
This document provides an overview of tourism in Central Luzon, Philippines. It discusses the growth of world tourism from 25 million visitors in 1950 to over 700 million in 2000. Central Luzon has seen significant investment and economic growth in recent years, with investments ranking 2nd nationally between 2004-2006. The tourism industry in Central Luzon and the Philippines as a whole has experienced strong growth over the past decade and is projected to continue growing in the coming years.
- In Q1 2015, investment activity in commercial property remained high across many Asia Pacific markets, though sentiment was lacklustre in some places like Hong Kong.
- Office markets were strong in many cities, with high demand driving rents up. Retail and residential saw more challenges.
- Major transactions over the quarter included the sale of office buildings in Sydney and Shanghai, and a hotel and retail property in Brisbane.
The document discusses the subprime crisis, including the key players and events that led to the housing bubble and its bursting, which triggered a global financial crisis. It then outlines the impact on various countries and financial institutions, as well as the various bailout measures taken by governments around the world to stabilize their economies and financial systems in response to the crisis.
Can europe create_billion_dollar_tech_companies_-_the_factsPawel Chudzinski
This document provides a summary of billion-dollar ("unicorn") tech companies founded in Europe since 2000. It finds 30 such companies, compared to 39 in the US over the same period. Most European unicorns are in eCommerce, founded by co-founders in their 30s, and it takes an average of 8 years to reach a liquidity event. While rare, European entrepreneurs have demonstrated the ability to build huge billion-dollar companies.
San Diego Bay Integrated Natural Resources Management PlanPort of San Diego
The Port regularly sponsors studies to evaluate eelgrass restoration techniques in San Diego Bay. Assistant Professors and graduate students from San Diego State University conducted a study on the effects of habitat structure on fish recruitment and species diversity in eelgrass beds. The project also studied the effects on species density and diversity in native eelgrass beds and where eelgrass has been harvested. Through this study, the Port was seeking knowledge regarding the most effective planting and harvesting schemes that would provide the best results for the bay's ecosystem.
Mobile learning in Japan has seen significant growth. The domestic e-learning market was worth $1.36 billion in 2010, with the B2B segment making up $690 million of that total. While feature phones still dominate the mobile market, smartphones are growing in popularity and driving new mobile learning apps and services. Examples include language learning apps, mobile-optimized university courses, and cloud-based platforms for creating mobile learning content and assessments. However, emerging technologies like augmented reality and location-based learning have yet to be widely applied to mobile education in Japan.
Competative study between coke vs. pepsisalilsharma
This document appears to be a research project submitted by Salil Kumar Sharma towards completion of an MBA degree at GLA University in Mathura. The project examines the competitive landscape between Coca-Cola and Pepsi in India through consumer research and analysis of the soft drink industry. It acknowledges the guidance of project guide Mr. Darshan Saxena and others. The contents include an introduction to the topic, literature review, overview of the soft drink industry in India, profiles of Coca-Cola and Pepsi, their brands, marketing strategies, and findings and recommendations from the research.
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1. COMMUNICATION www.rsc.org/chemcomm | ChemComm
Self-exchange electron transfer in high oxidation state non-oxo metal
complexes: amavadin{
Jeremy Lenhardt,a Bharat Baruah,b Debbie C. Crans*b and Michael D. Johnson*a
Received (in Berkeley, CA, USA) 27th July 2006, Accepted 20th September 2006
First published as an Advance Article on the web 12th October 2006
DOI: 10.1039/b610751f
The electron transfer self-exchange rate constant between [V(hidpa)2]22 + [IrCl6]22 A [V(hidpa)2]2 + [IrCl6]32 (2)
the oxidized and reduced forms of amavadin equals y1 6
105 dm3 mol21 s21 at 25 uC and represents the first
2[V(hidpa)2]2 + H2Asc A 2[V(hidpa)2]22 + Asc + 2H+ (3)
unambiguous example for a vanadium(IV/V) couple.
The determination of self-exchange electron transfer rate constants While the Ce4+ oxidation rates were too fast to measure, the
for vanadium(IV/V) couples remains a challenging problem that is oxidation stoichiometry is truly 1 : 1 which has been used by
overcome in studies of the natural product, amavadin. Two major others10 to produce vanadium(V) containing amavadin. The
impediments are: (1) coordination geometry changes between these reaction kinetics for eqn 2 and 3 each showed a first order
two states1 and (2) a competing inner-sphere pathway through dependence on both the vanadium complex and the oxidant (or
their ‘‘yl’’ type oxygens.2 These have led to inconsistent estimates reductant). No hydrogen ion dependence was observed for the
of self-exchange rate constants for hydroxyoxovanadate(IV/V) of [IrCl6]22 oxidation between 0.10 mol dm23 HCl (k = 3.2 ¡ 0.3 6
y1023 and y103 dm3 mol21 s21.3,4 In amavadin the metal 106 dm3 mol21 s21) and 0.0010 mol dm23 HCl (k = 3.3 ¡ 0.2 6
coordination geometry does not change when oxidized from the 106 dm3 mol21 s21). This is expected since amavadin has no site
+4 to the +5 oxidation states.5 Furthermore both amavadin and its for protonation over this pH range. The following rate law can be
oxidized form lack an ‘‘yl’’ type oxygen.5 As a result, amavadin is written, eqn 4.
an ideal system in which an unambiguous self-exchange rate
constant may be determined for a vanadium(IV/V) couple. d[V(V)]/dt = kIr[V(hidpa)222][IrCl622] (4)
Amavadin possesses an eight-coordinate, non-oxo vanadium
center coordinated to two tetradentate ligands, 2,29-(hydroxyimi- In contrast, in the ascorbic acid reduction of oxidized amavadin,
no)dipropionate (hidpa).5 The unusual structure of this com- a simple inverse dependence on H+ was observed, Fig. 1. A rate
pound, its presence in mushrooms and its intriguing reactivity, law consistent with these observations can be written, eqn 5.
including oxygen activation, have maintained scientists’ interest in
2d[V(V)]/dt = kasc[V(hidpa)22][H2Asc][H+]21 (5)
this class of compounds for decades.6 Because vanadium forms
very strong high oxidation state oxo-metal complexes, outer-
The zero y-intercept suggests that reduction proceeds solely via
sphere electron transfer studies of these systems are often
monohydrogen ascorbate, HAsc2, since amavadin has no acidic
problematic, but can be accessed with this ligand. Since additional
hydrogens in the pH range studied, Scheme 1.
metal ions such as Mo,7 Ti,8 Zr,8 and others9 yield similar
coordination complexes, analogous studies may also be carried
with other high oxidation state nonoxo-metal complexes with this
ligand.
Before a fundamental kinetic study of amavadin’s redox
reactions was undertaken, the reaction stoichiometries were
determined. Job plots for the oxidation of [V(hidpa)2]22 with
Ce4+ or [IrCl6]22 and the reduction of [V(hidpa)2]2 by ascorbic
acid (H2Asc) in aqueous media all showed simple 1 : 1 (eqn 1 and
2) or 2 : 1 (eqn 3) stoichiometries.
[V(hidpa)2]22 + Ce4+ A [V(hidpa)2]2 + Ce3+ (1)
a
Department of Chemistry and Biochemistry, New Mexico State
University, Las Cruces, New Mexico, USA. E-mail: johnson@nmsu.edu;
Fax: +1 505 646 2394; Tel: +1 505 646 3627
b
Department of Chemistry, Colorado State University, Fort Collins,
Colorado, USA. E-mail: crans@lamar.colostate.edu;
Fax: +1 970 491 1801; Tel: +1 970 491 7635
{ Electronic supplementary information (ESI) available: Job plots, kinetic Fig. 1 Inverse hydrogen ion dependence of ascorbic acid reduction of
data. See DOI: 10.1039/b610751f amavadin. Conditions: I = 1.0 mol dm23 LiCl, T = 25.0 uC.
This journal is ß The Royal Society of Chemistry 2006 Chem. Commun., 2006, 4641–4643 | 4641
2. complex, the three signals observed presumably represent three
different isomers of the oxidized form of amavadin. The 51V line
broadening experiment measures the line broadening induced by
vanadium(IV) of each signal. Fig. 2 (insert) shows that the amount
of broadening is directly proportional to the amavadin
(vanadium(IV)) concentration. A value for k22 can be calculated
Scheme 1 from the slope of these lines, Table 2.13,14 An average self-exchange
rate constant of 1 ¡ 0.5 6 105 dm3 mol21 s21 was observed for
Based on Scheme 1, and using the pKa1 for ascorbic acid, 4.17,11 each isomer. Within experimental error, there was no difference in
a second order rate constant can be calculated since kasc = Ka1ka. self-exchange rate constants for these three isomers.
The rate constant is given in Table 1. The line broadening experiment was carried out at 0.10 and
Assuming that both these reactions are outer-sphere electron 1023 mol dm23 HCl. As found for the iridium(IV) oxidation study
transfer processes allows the use of Marcus theory to calculate a above, no difference was observed, thereby eliminating a proton
self-exchange rate constant, k22, for the V(IV/V) couple using the dependence in this acid range. This observation supports Scheme 1
physical data provided in Table 1.12 Values for k22, of 1.6 6 104 where the observed proton dependence was ascribed to the
and 2.8 6 104 dm3 mol21 s21, respectively, were calculated for the deprotonation of ascorbic acid and not deprotonation of
iridium and ascorbate reactions. These two rate constants are self- amavadin.
consistent and indicate the electron transfer reactions are adiabatic Due to the aforementioned problems in determining self-
in nature. exchange rate constants for vanadium(IV/V) couples, there is a
In addition to the Marcus estimations, a direct measurement paucity of data for comparison. The self-exchange electron transfer
was also carried out using 51V NMR line broadening.2 The rate constant for aqueous alkaline vanadium(IV/V), [VO(OH)3]0/2,
vanadium(V) form of amavadin was produced by addition of one has been reported using the Marcus cross relation. Two very
equivalent of Ce(IV) to a solution of amavadin. Fig. 2 shows the different values were reported, (k22 y 1023 dm3 mol21 s21) and
51
V spectrum of oxidized amavadin in D2O at acidic pH. Since a (k22 y 10–103 dm3 mol21 s21).3,4 The inconsistency was attributed
racemic mixture of the hidpa ligand was used to synthesize the to non-adiabaticity of the cross reactions.3 In contrast, the self-
exchange rate constants in the present study, obtained by both
Table 1 Kinetic and thermodynamic data for amavadin redox Marcus calculation and direct measurement, vary by less than a
reactions factor of four. Despite the ambiguity in the values for [VO(OH)3]0/2,
k12a/dm3 K11/dm3 Eu/V, k22b/dm3 the self-exchange rate constant in the amavadin system is at least
Reactant mol21 s21 mol21 s21 NHE mol21 s21 2 orders of magnitude higher than the corresponding aqueous
oxohydroxide couple. This reflects the smaller structural differences
HAsc?/HAsc2 1.4 6 105 1.0 6 105 c 0.70d 2.8 6 104
[IrCl6]22 3.2 6 106 2.0 6 105 e 0.96 f 1.6 6 104
between the oxidized and reduced forms of amavadin than those in
a
k12 = ka or kIr in text, T = 25.0 uC, I = 1.0 M (LiCl). b Calculated
the aqueous vanadium(IV/V) system.2 These smaller changes reduce
using Eu (VV/IV) = 0.75 V, NHE, ref. 3. c See ref. 18. d See ref. 19 the inner sphere reorganization energy barrier and thereby increase
for the HAsc?/HAsc2. e See ref. 20. f See ref. 21. the self-exchange rate constant for amavadin.
Iron containing enzymes have been reported to enhance
biological electron transfer processes compared to aqueous iron.
For example, the observed self-exchange rate constant for the
[Fe(OH2)6]2+/3+ couple is 33 dm3 mol21 s21 15 whereas for the
cytochrome c couple, rate constants above 104 dm3 mol21 s21 are
reported.16,17 These rate enhancements have been attributed
primarily to reductions in reorganization energies within the
protein matrix.17 Similarly, the natural product, amavadin, shows
significantly enhanced electron transfer processes compared to the
aqueous vanadium(IV/V) system.
In summary, this work provides a self-consistent vanadium(IV/
5 3 21 21
V) self-exchange rate constant, k = 1.0 ¡ 0.2 6 10 dm mol s
using Marcus theory and line broadening experiments. As the first
example of a non-oxo vanadium(IV/V) redox system in aqueous
Table 2 Self-exchange rate constants for amavadin enantiomers
Isomer (resonance frequency, ppm)a k22b/dm3 mol21 s21
2217 1.0 ¡ 0.5 6 105
51 23
Fig. 2 The V NMR spectrum of 0.050 mol dm oxidized amavadin, 2234 1.2 ¡ 0.5 6 105
VOCl3 used as reference. Conditions: 0.10 mol dm23 HCl, I = 1.0 mol 2252 1.3 ¡ 0.5 6 105
a
dm23 LiCl, T = 25.0 uC. Insert: line width broadening as a function of Chemical shifts reported in reference to VOCl3, 50 mM
vanadium(IV) concentration. Inset linear fits correspond to: 2252 ppm m, amavadin used for kinetic study. Conditions: 0.10 mol dm23 HCl,
I = 1.0 mol dm23 LiCl, T = 25.0 uC. b Calculated as in ref. 13.
2234 ppm $, 2217 ppm &.
4642 | Chem. Commun., 2006, 4641–4643 This journal is ß The Royal Society of Chemistry 2006
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