Ketones In Solution Research Articles

Solvent effect of ionic liquids on the distribution constant of 2-thenoyltrifluoroacetone and its nickel(II) and copper(II) chelates and the evaluation of the solvent properties based on the regular solution theory

Distribution constants of 2-thenoyltrifluoroacetone (Htta) and its Ni(II)and Cu(II) chelates between 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (C n mimTf 2N; n = 4, 6, and 8) as ionic liquid (IL) and an aqueous phase were determined. The enol fraction of Htta in ILs was spectrophotometrically measured to calculate the distribution constant of the enol form ( K D,HE) of Htta. The K D,HE values in ILs were evaluated by comparing those in various molecular solvents such as alkanes, aromatic hydrocarbons, chlorohydrocarbons, ethers, ketones, and esters previously reported on the basis of the regular solution theory (RST). It was elucidated that the IL solutions of Htta (enol) can be taken as apparently regular solutions as expected in the organic solvents. On the other hand, the effect of ILs on the distribution constant of metal(II) chelates ( K D,M) was fairly complicated. The Cu(tta) 2-IL solutions behaved like the alkane and aromatic hydrocarbon solutions but the Ni(tta) 2-IL (C 4mimTf 2N) like ether and ketone solutions. In the Ni(II) case, some specific interactions between the Ni(II) chelate and IL was suggested. Finally, the solubility parameters of ILs were calculated using K D,HE by RST and were in good agreement with the literature values obtained by the enthalpy of vaporization.

Synthesis, Characterization, Reactivity Ratio and Photo Crosslinking Properties of the Copolymer of 4-Cinnamoyl Phenyl Methacrylate with Butyl Methacrylate

Copolymers of 4-cinnamoyl phenyl methacrylate (4-CPMA) and n-butyl methacrylate (BMA) were prepared in a methyl ethyl ketone (MEK) solution with benzoyl peroxide (BPO) as an initiator at 70°C. They were characterized with UV, IR, 1H-NMR, 13C-NMR, TGA, DSC and gel permeation chromatography. Copolymers were prepared by using different feed ratio of monomers. The monomer reactivity ratios determined by the method of Kelen-Tudos (K-T) were r1 (CPMA) = 2.32, r2 (BMA) = 0.56. The glass transition temperature of the copolymer shows a single Tg indicating the formation of random copolymer for all of the monomer feed composition. Thermogravimetric analysis in air has shown that the initial decomposition temperature of the copolymer was above 220°C. The photocrosslinking properties of the copolymer were examined by UV irradiation with polymer film.

Graft copolymerization of methoxyacrylethyl phosphate onto expanded poly(tetrafluoroethylene) facial membranes

AbstractExpanded poly(tetrafluoroethylene) (ePTFE) membranes were modified by graft copolymerization with methoxyacrylethyl phosphate (MOEP) in methyl ethyl ketone (MEK) solutions at ambient temperature using gamma irradiation. The effect of monomer concentration (3–30%) was studied and the modified membranes were characterized by weight increase, x‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), contact angle measurements, and differential scanning calorimetry (DSC). Results show that the ePTFE membrane had a degree of crystallinity of 59% and that this did not significantly change after grafting indicating that grafting occurs in the amorphous regions. SEM images showed a globular surface morphology for the grafted membranes. XPS was used to evaluate the chemical structure of the graft copolymer and to determine the XPS grafting extent using the C‐F (ePTFE membrane) and the C‐C (MOEP graft copolymer) peaks. The graft yield as well as grafting extent was found to increase with increasing monomer concentration. Concomitantly, the contact angle was found to decrease with increasing monomer concentration. No direct correlation was found between XPS grafting extent and the advancing water contact angle illustrating that the former does not adequately give an indication of the copolymer surface coverage of the first molecular layer. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Experiments on the Release of Gaseous Iodine from Gamma-Irradiated Aqueous CsI Solution and Influence of Oxygen and Methyl Isobutyl Ketone (MIBK)

Volatile iodine production due to radiation chemical effects is known to be an important uncertainty source in the evaluation of the source term for severe accidents of light water reactors (LWRs). The gaseous release fractions of molecular iodine and organic iodine from gamma-irradiated 10−4 mol/L cesium iodide aqueous solution were measuredwith the dose rate ∼ 7 kGy/h at room temperature. The solution was buffered with 0.1 mol/L boric acid and sodium hydroxide (pH ∼7) and contained up to 10−3 mol/L methyl isobutyl ketone (MIBK) as an organic additive. The concentrations of MIBK in the solution and oxygen in the sweep gas were changed as experimental parameters. The total iodine release fraction of the original aqueous inventory and the fraction released as organic iodine were 2–47 and 0.02–1.5%, respectively, at the end of 2 h of irradiation. They were dependent on both the aqueous MIBK concentration and oxygen concentration in the sweep gas. Under a constant cover gas condition, the total iodine release showed a decreasing trend and theorganic iodine release showed an increasing trend when the MIBK concentration increased. This behavior can be explained by the branching of the reaction path of radiolytic degradation of ketones depending on the availability of dissolved oxygen, and competition between iodine and organic compounds on the consumption of radicals produced by water radiolysis.

Experiments on the Release of Gaseous Iodine from Gamma-Irradiated Aqueous CsI Solution and Influence of Oxygen and Methyl Isobutyl Ketone (MIBK)

Experiments on the Release of Gaseous Iodine from Gamma-Irradiated Aqueous CsI Solution and Influence of Oxygen and Methyl Isobutyl Ketone (MIBK)

Large-Size Pyrrolidine-Based Polyene Single Crystals Suitable for Terahertz Wave Generation

We report on the growth of large pyrrolidine-based polyene single crystals from methyl ethyl ketone (MEK) solutions for nonlinear optical applications. The polyene crystals grown exhibit a suitable morphology and surface roughness and good optical quality. We successfully demonstrated THz wave generation with as-grown polyene crystals. Although the crystal cut was not optimized and phase-matching conditions were not fulfilled, we achieved a similar or higher THz generation efficiency compared to the well-known inorganic ZnTe emitter crystals.

Mass Diffusion Coefficients of Cellulose Acetate Butyrate in Methyl Ethyl Ketone Solutions at Temperatures between (293 and 323) K and Mass Fractions from 0.05 to 0.60 Using the Soret Forced Rayleigh Scattering Method

The binary mass diffusion coefficients of cellulose acetate butyrate in methyl ethyl ketone solutions (CAB + MEK) have been measured under atmospheric pressure at temperatures from (293 to 323) K and mass fractions from 0.05 to 0.6. The present experimental apparatus is based on the Soret forced Rayleigh scattering method (S-FRSM), which utilizes the Soret effect to create periodic spatial concentration modulation of micrometer-order fringe spacing in a sample binary liquid mixture due to the absorption of an optical interference grating generated by two intersecting heating laser beams. The decay of the concentration modulation by the mass diffusion process is monitored by the diffraction of a probing laser beam. This method provides several advantages in comparison with conventional techniques such as Taylor dispersion or diaphragm cells; namely, a single measurement can be performed within a short time [(10−3 to 10−2) s], with small temperature and concentration changes (ΔT < 10−2 K and Δc < 10−5) usin...

Micellization in solutions of hybrid block copolymer of poly(methyl methacrylate) and hyperbranched perfluorinated poly(phenylene germane)

Fractions of the product resulting from the polymerization of methyl methacrylate in the presence of hyperbranched perfluorinated poly(phenylene germane) have been studied by dynamic and static light scattering and capillary viscometry in methyl ethyl ketone solutions. The hybrid product is obtained via the reaction of the chain transfer of methyl methacrylate propagating radicals to pentafluorophenyl groups. Eight fractions have been isolated by fractional precipitation, including fractions of the linear-dendrite block copolymer. Light scattering studies have shown that hybrid macromolecules containing 15–20 wt % hyper-branched fragments form micelles in solutions.

The kinetics and energetics of transitions between water repellent and wettable soil conditions: a linear free energy analysis of the relationship between WDPT and MED/CST

AbstractSoil water repellency is commonly assessed using the Water Droplet Penetration Time (WDPT) and Molarity of Ethanol (MED) or Critical Surface Tension (CST) tests. The former is a kinetic measurement indicating the persistence of water repellency; the latter, a thermodynamic measurement, gives the initial severity of water repellency. This study aims to provide a theoretical framework to understand (i) what determines differences in persistence and initial severity of soil water repellency and (ii) correlations between such data. A linear free energy relationship between Solution Droplet Penetration Time (SDPT) and the difference between the surface tension of the droplet solution, γsol, and the Critical Surface Tension of the soil, γcx, has been derived. Here: γsol is the surface tension of water (for WDPT) or the solution being used (SDPT); N is the number of adsorbed molecules per unit area; k the Boltzmann constant; T the temperature; A is 1/SDPT when γcx = γsol; and f is an experimentally determined parameter. WDPT, SDPT (ethanol/water and propan‐1‐ol/water), and CST measurements for a group of sandy soils support this analysis. The value of f obtained (4·2 ( ± 0·4)), suggests that the surface free energy contribution to the free energy of activation of wetting is given by the difference between the cohesive energy of the molecular film adsorbed on the soil grains and that of the wetting solution.In this interpretation: γcx is determined by the cohesive energy of the organic film adsorbed on the soil; WDPT is determined by the difference in cohesive energies between this adsorbed film and the droplet solution; and soil‐to‐soil variations in both WDPT and γcx are due to organic films of different cohesive energies present on the soil particles. For aqueous solutions of simple linear alcohols and ketones, SDPT depends on γsol but is independent of the compound used to control γsol. Copyright © 2007 John Wiley &amp; Sons, Ltd.

Studies on the Preparation, Characterization and Corrosion Behaviour of Injection Molded 316L Steel Electrochemically Coated by Poly{trans[dichloro (4-vinylpyridine) ruthenium

The present work describes the studies on corrosion of powder injection molded 316L stainless steel potentiostatically coated by poly{trans[RuCl2(vpy)4]} where vpy (4- vinylpyridine) acts as ligand. Scanning Electron Microscopy (SEM) coupled to an Energy Dispersive X-Ray Analysis (EDAX) characterized the coated electrodes. Anodic polarization tests were performed in 3% NaCl to estimate the anodic dissolution current density of the electrode coated by the polymeric material. In addition, the specimens were exposed to salt spray and acid rain simulated environment. The microestrutural analysis indicated that the films were approximately 58 μm thick. Cyclic voltammetry experiments were carried out in 0.1M HTBA/methyl isobutyl ketone solution. The results revealed a scan rate dependent wave corresponding to a Ru2+/Ru3+ redox reaction, thus confirming the presence of ruthenium as metallic center in the polymer backbone. Pitting corrosion was observed in coated specimens only after thirty days of exposure to salt spray and after two days of exposure to acid rain simulated environment.

Polymer–nanoparticle interfacial interactions in polymer nanocomposites: Confinement effects on glass transition temperature and suppression of physical aging

AbstractThe effects of confinement on glass transition temperature (Tg) and physical aging are measured in polystyrene (PS), poly(methyl methacrylate) (PMMA), and poly(2‐vinyl pyridine) (P2VP) nanocomposites containing 10‐ to 15‐nm‐diameter silica nanospheres or 47‐nm‐diameter alumina nanospheres. Nanocomposites are made by spin coating films from sonicated solutions of polymer, nanofiller, and dye. The Tgs and physical aging rates are measured by fluorescence of trace levels of dye in the films. At 0.1–10 vol % nanofiller, Tg values can be enhanced or depressed relative to neat, bulk Tg (Tg,bulk) or invariant with nanofiller content. For alumina nanocomposites, Tg increases relative to Tg,bulk by as much as 16 K in P2VP, decreases by as much as 5 K in PMMA, and is invariant in PS. By analogy with thin polymer films, these results are explained by wetted P2VP–nanofiller interfaces with attractive interactions, nonwetted PMMA–nanofiller interfaces (free space at the interface), and wetted PS–nanofiller interfaces lacking attractive interactions, respectively. The presence of wetted or nonwetted interfaces is controlled by choice of solvent. For example, 0.1–0.6 vol % silica/PMMA nanocomposites exhibit Tg enhancements as large as 5 K or Tg reductions as large as 17 K relative to Tg,bulk when films are made from methyl ethyl ketone or acetic acid solutions, respectively. A factor of 17 reduction of physical aging rate relative to that of neat, bulk P2VP is demonstrated in a 4 vol % alumina/P2VP nanocomposite. This suggests that a strategy for achieving nonequilibrium, glassy polymeric systems that are stable or nearly stable to physical aging is to incorporate well‐dispersed nanoparticles possessing attractive interfacial interactions with the polymer. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2935–2943, 2006

Studies on copolymers of 3-methacryloyloxystyryl-4′-methylphenyl ketone and methyl methacrylate

Copolymers with various contents of 3-methacryloyloxystyryl-4′-methylphenyl ketone (MSMPK) and methyl methacrylate (MMA) were prepared in methyl ethyl ketone solution using benzoyl peroxide as a free radical initiator at 70 °C. Characterization of the resulting polymers was done by UV, FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The copolymer compositions were determined by 1H NMR analysis. The monomer reactivity ratios were calculated using linearization methods such as Finemann–Ross ( r 1 = 0.9439 and r 2 = 0.3656), Kelen–Tüdös ( r 1 = 0.9726 and r 2 = 0.4172), and extended Kelen–Tüdös ( r 1 = 0.9731 and r 2 = 0.4055) methods as well as by a non-linear error-in-variables model (EVM) method using the computer program RREVM ( r 1 = 0.9043 and r 2 = 0.3901). The molecular weights ( M ¯ w and M ¯ n ) and the polydispersity index of the copolymers were determined by gel permeation chromatography. The thermal stability of the copolymers solution increases with increase in concentration of MSMPK. Glass transition temperatures were determined by differential scanning calorimeter under nitrogen atmosphere. The photoreactivity of the copolymers having pendant chalcone moieties was studied in chloroform.

Identification of Expression Patterns Associated with Hemorrhage and Resuscitation: Integrated Approach to Data Analysis

Although transcriptional profiling is a well-established technique, its application to systematic studying of various biological phenomena is still limited because of problems with high-volume data analysis and interpretation. This research project's objective was to create a comprehensive summary of changes in gene expression after hemorrhagic shock (HS), reliant and impartial of multiple variables, such as resuscitation treatments, organ analyzed, and time after impact. Rat model of severe (40% total blood loss) HS was employed. Hemorrhagic shock was treated with 6 different resuscitation strategies: (1) racemic lactated Ringer's (DL-LR); (2) L-lactated Ringer's (L-LR); (3) ketone Ringer's (KR); (4) pyruvate Ringer's (PR); (5) 6% hetastarch (Hex); (6) 7.5% hypertonic saline (HTS). Nonresuscitated and nonhemorrhaged rats served as controls. Ketone and pyruvate Ringer solutions were identical to the lactated Ringer's solution except for equimolar substitution of lactate with beta-hydroxybutyrate and sodium pyruvate, respectively. Total RNA from liver, lung, and spleen was isolated immediately (0 hour) and 24 hour postresuscitation. Each organ, time point and treatment was profiled using individual cDNA array (1,200 genes), to produce 183 separate data files. Methods of analysis included one-way and unbalanced factorial ANOVA, Sokal-Michener average linkage clustering and contextual mapping. : Unresuscitated HS produced the highest number (56) of upregulated expressions in spleen and lungs. HEX and HTS affected mostly pulmonary genes (22 and 9). Fourteen genes changed in response to combination of all three factors: treatment, organ, and time. Eighteen genes were identified as treatment-specific. Fifteen genes adjusted expression 24 hour post-treatment. The largest number of genes with altered expression (168) responded differently in all three organs. In this study 15 gene clusters were pinpointed. Contextual mapping identified novel and confirmed known pathways contributing to hemorrhage/resuscitation. We have reliably identified genes and pathways that are affected by HS and are responsive to resuscitation. Gene expression in various organs is affected differentially by HS, which can be further modulated by the choice of resuscitation strategy.

Laser photolysis studies of the phenolic H-atom transfer mechanism for a triplet π,π ∗ ketone in solution revisited

The mechanism of the H-atom transfer from phenols or thiophenols to triplet π,π ∗ 5,12-naphthacenequinone (5,12-NQ) has been examined by means of laser flash photolysis at 295 K. Based on the Hammett plots and the Rehm–Weller equation for the quenching rate constants, the phenolic H-atom transfer from phenols or thiophenols to triplet π,π ∗ 5,12-NQ is shown to proceed via the electron transfer followed by proton transfer. The previously proposed mechanism for H-atom transfer of π,π ∗ triplets, that proton transfer is followed by electron transfer, was not verified in the present systems.

Homopolymer and copolymers of 4‐methacrylamidophenyl‐4‐methoxystyryl ketone with methyl methacrylate: Synthesis, characterization, reactivity ratios, and photocrosslinkable properties

Abstract4‐Aminophenyl‐4‐methoxystyryl ketone (APMSK) was prepared by reacting 4‐aminoacetophenone and 4‐methoxybenzaldehyde in the presence of sodium hydroxide as base catalyst. The methacrylamide monomer, 4‐methacrylamidophenyl‐4‐methoxystyryl ketone (MPMSK), was synthesized by reacting APMSK with methacryloyl chloride in the presence of triethylamine. Free‐radical solution polymerization technique was used to prepare the homo‐ and copolymers of different feed compositions of MPMSK with methyl methacrylate in methyl ethyl ketone solution at 70°C, using benzoyl peroxide as the initiator. The polymers were characterized by UV, IR, 1H‐NMR, and 13C‐NMR spectral techniques. The reactivity ratios of both comonomers were calculated using Fineman–Ross, Kelen–Tüdös, extended Kelen–Tüdös, and a nonlinear error‐in‐variables model (EVM) method using a computer program, RREVM. The molecular weights (M̄w and M̄n) and polydispersity indices of the polymers were determined using size exclusion chromatography. The glass‐transition temperatures of the polymers were determined by differential scanning calorimetry. The thermal stability of the polymers was measured by thermogravimetric analysis in air. The photoreactivity of the polymers was studied in chloroform solutions in the presence and absence of various triplet sensitizers. The effect of concentration of homopolymer and composition of the copolymers on the rate of photocrosslinking of the polymers was investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006

Effects of the Resuscitation Fluid and the Hemoglobin Based Oxygen Carrier (HBOC) Excipient on the Toxicity of the HBOC: Ringer'sD,L-Lactate, Ringer'sL-Lactate, and Ringer's Ketone Solutions

Hemoglobin based oxygen carriers (HBOC) are resuspended in "excipients" consisting of Ringer's D,L-lactate containing antioxidants to prevent methemoglobin formation during storage. Investigators have reported cardiac arrhythmias following infusion of Ringer's D,L-lactate solution. Studies have shown that D-lactate stimulates human granulocytes to generate oxygen free radicals and L-lactate inhibits glycolysis. Patients receiving HBOC in Ringer's D,L-lactate excipient are also resuscitated or hemodiluted with Ringer's lactate solution. Oxygen-free radicals generated by Ringer's D,L-lactate and HBOC may oxidize nitric oxide in endothelial cells, causing the vasoconstrictor effects reported following HBOC infusion, and activate NF-kappab and the apoptotic cascade. The combination of Ringer's D,L-lactate and HBOC in Ringer's D,L-lactate excipient may be responsible for the severe adverse events observed in clinical studies of HBOC.Veech has recommended replacing the 27 mM of lactate in Ringer's with 27 mM D-betahydroxybutyrate (BHB). BHB reduces the generation of oxygen free radicals by mitochondria and human granulocytes.

Sorption studies of cesium on TiO 2–SiO 2 mixed gel spheres

TiO 2–SiO 2 mixed gel spheres used for the sorption studies of cesium were prepared via sol–gel method. The source solutions used for the process were prepared from different mixtures of 1 M TiCl 4 and 1 M Na 2SiO 3 solutions and converted into droplets in a gelation column. The suitable spheres for cesium adsorption were obtained using a methyl isobutyl ketone solution as the drop formation medium and ammonia as the gelling agent. The mixed oxide gels were identified and characterized by Analysis Adsorptive (N 2), DTA/TGA, FTIR and XRD analyses. The sorption behavior of Cs + cations on TiO 2–SiO 2 mixed gel spheres has been studied as a function of TiO 2 weight ratio, pH, time, cation concentration, temperature and competing ions. Sorption data have been interpreted in terms of Freundlich and Dubinin–Radushkevich equations. Sorption of Cs + cations were found to be endothermic in nature with Δ H° (kJ/mol) of 5.06, and Δ S° (kJ/(mol K)) of 0.06. Negative Δ G° value obtained for Cs + cations indicates the spontaneity of its sorption on mixed oxide gel spheres.

Alternative Protocol for Oxidation in Water: An Effective Epoxidation System Promoted by the Combination of Oxone® and an Amphiphilic Ketone.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Preparation of TiO 2–SiO 2 mixed gel spheres for strontium adsorption

A simple external gelation process, taking full advantage of the gelation features of titanium and silica, was developed to prepare TiO 2–SiO 2 mixed gel spheres suitable for strontium adsorption. The source solutions used for the process were prepared from different mixtures of 1 M TiCl 4 and 1 M Na 2SiO 3 solutions and converted into droplets in a gelation column. The suitable spheres for strontium adsorption were obtained using a hexone (methyl isobutyl ketone) solution as the drop formation medium and ammonia as the gelling agent. The mixed oxide gels were identified and characterized by DTA/TGA, FTIR and XRD analysis. The parameters affecting the strontium adsorption, such as weight ratio of TiO 2, pH, temperature, shaking time and selectivity towards competing ions were investigated. Sorption data have been interpreted in terms of Freundlich, Langmuir and Dubinin–Radushkevich equations. Thermodynamic parameters for the sorption system have been determined at four different temperatures. The value of Δ H° = 39.553 kJ/mol and Δ G° = −16.687 kJ/mol at 296 K prove that the sorption of strontium on mixed oxide gel is an endothermic and a spontaneous process.

Studies on photocrosslinkable copolymers of 4-methacryloyloxyphenyl-3′,4′-dimethoxystyryl ketone and methyl methacrylate

Copolymers with various contents of 4-methacryloyloxyphenyl-3′,4′-dimethoxystyryl ketone (MPDSK) and methyl methacrylate (MMA) were prepared in methyl ethyl ketone solution using benzoyl peroxide as a free radical initiator at 70 °C. Characterization of the resulting polymers was done by UV, FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The copolymer compositions were determined by 1H NMR analysis. The monomer reactivity ratios were calculated using linearisation methods such as Finemann–Ross ( r 1 = 0.4283 and r 2 = 0.3050), Kelen–Tudos ( r 1 = 0.4264 and r 2 = 0.2606), and extended Kelen–Tudos ( r 1 = 0.4022 and r 2 = 0.2704) methods as well as by a non-linear error-in-variables model (EVM) method using the computer program RREVM ( r 1 = 0.4066 and r 2 = 0.2802). The molecular weights ( M ¯ w and M ¯ n ) and the polydispersity index of the copolymers were determined by gel permeation chromatography. The thermal stability of the copolymers increases with increase in concentration of MPDSK. Glass transition temperatures were determined by differential scanning calorimeter under nitrogen atmosphere. The photoreactivity of the copolymers having pendant chalcone moieties was studied in chloroform solution.