William Risen Jr - Academia.edu (original) (raw)
Papers by William Risen Jr
The Journal of Physical Chemistry, Nov 1, 1977
Publication costs assisted by Brown University and the Union Carbide Corporation Far-infrared ion... more Publication costs assisted by Brown University and the Union Carbide Corporation Far-infrared ion motion bands have been observed and assigned in the spectra of dry synthetic zeolites X and Y containing Li' , Na+, K+, Rb' , Cs+, Ag+, Ca2+, Sr2+, and Ba2+ cations. The site I' and site I1 cation vibrational bands overlap and form the strongest feature in the spectra of samples exchanged with monovalent ions. The site I cation band appears at lower frequency than the site I1 envelope in these samples, but in divalent ion exchanged zeolites the opposite order occurs. A very low frequency site I11 cation band, typical of monovalent X zeolites, has been observed in CsY. For a given cation, the frequency on X is higher than on Y due to the higher framework charge of X zeolites. The vibrational frequencies also follow an approximate m-1/2 dependence for the two types of cation and the two forms of the zeolite. Solvation of the monovalent zeolites with H20, THF, Me2S0, pyridine, and CH2C12 results in the appearance of a new band at higher frequency than the ion-framework modes which concurrently diminish in intensity, especially the site I11 band. The high frequency band is due to ion motion in a solvation shell which is unsymmetric at low hydration levels and at all solvation levels with organic adsorbates. In addition to a cation mass dependence, the ion-solvent frequencies are also dependent on the adsorbent's effective dielectric constant which is greater in X than Y zeolites. Increasing solvation shifts the ion-framework vibrations to lower frequency, but this shift with the organic adsorbates is primarily an indirect effect due to solvent delocalizing the framework charge. The implications of the cation vibrational frequencies for the mechanism of ionic conduction are considered in terms of a simple free-ion model. Ion transport in Y zeolites which have a large number of vacant cation sites so that each jump may be considered an independent event is adequately explained by this model, but ion transport in X zeolites is best interpreted in terms of cooperative effects.
Journal of the American Chemical Society, Apr 1, 1970
The infrared spectrum of tetrahydrofuran solutions of a number of alkali metal salts has been obs... more The infrared spectrum of tetrahydrofuran solutions of a number of alkali metal salts has been observed between 90 and 600 cm-1. Some measurements were made in other solvents (dimethyl sulfoxide, pyridine, and piperidine). In every case, a band was observed which could be associated with alkali ion vibration. The frequency shows a dependence upon anion in THF as well as a dependence upon solvent. The effect of pressure to 20 kbar, frequency shift with Lif isotope substitution, the variation of band intensity with concentration, and Raman spectra were studied for selected salts in THF. The results suggest that the infrared band arises from motion in the solutions which is similar to that which occurs on the excitation of a highly localized phonon at an impurity center in crystals. The motion may be approximated as the alkali ion vibrating in a cage, under the influence of electrostatic and repulsion forces. The anion is a cage component in THF solutions while only solvent molecules are involved in DMSO. The force constant for the net force resisting the displacement of the alkali ion was calculated from the experimental results. Force constants of the same magnitude arise from a solution model in which the electrostatic terms are expressed on a molecular basis and repulsion by exponential terms.
Journal of Catalysis, Jun 1, 1985
Abstract The reduction and subsequent oxidation of Ag(I)-containing films of polyfluorocarbon sul... more Abstract The reduction and subsequent oxidation of Ag(I)-containing films of polyfluorocarbon sulfonic acid (Nafion) have been studied spectroscopically, electron microscopically, and kinetically. The ultraviolet-visible and infrared spectral features observed in situ during these processes are interpreted in terms of the formation of Ag particles and their surface oxidation upon exposure to air or oxygen. The particle size distributions are narrow and give average diameters of 20–30 A for various reductive and oxidative treatments. The kinetics of the oxidation, which were followed by observing the growth of silver-silver oxide charge transfer absorption at 370 nm, are analyzed in terms of two parallel reactions. The first, postulated to give atomically adsorbed oxygen, is about 10 times faster than the postulated slower formation of molecularly adsorbed oxygen.
Abstract The Raman spectra of 10B, 11B, 16O, 18O, and mixed isotopic compositions of B2O3 (gl) ar... more Abstract The Raman spectra of 10B, 11B, 16O, 18O, and mixed isotopic compositions of B2O3 (gl) are reported. The 808 cm−1 band assigned to the boroxol ring structure is found to shift upon oxygen isotope substitution, and not to depend on the boron mass. It is replaced by four band, in the intensity ratio 1 : 3 : 3 : 1, in the case of the 50% 16O-50% 18O-containing material. On the other hand, the frequencies of other principal bands depend on the masses of both boron and oxygen. The about 1260 cm−1 band, in particular, depends on the masses of both, and shifts without broadening upon partial oxygen substitution. The analysis of these data shows that both a local unit, behaving as predicted for the boroxol ring, and a continuous random network of connecting bonds are manifested in the spectra.
Unknown eBooks, Dec 19, 1975
Abstract : The application of a tensile stress to a macroscopic monocrystalline fiber of a polydi... more Abstract : The application of a tensile stress to a macroscopic monocrystalline fiber of a polydiacetylene, an extended-chain polymer, causes the Raman-observed C triple bond C and C=C in-chain vibrational frequencies to decrease linearly with elongation. The polymer studied, poly-HDN, results from the solid-state polymerization of R-C triple bond C triple bond C-R where R = CH2OCONHC6H5. This experimental relationship between the molecular bond (spectroscopic) effects and the macroscopic properties is analyzed by relating the bond moduli (force constants) and Young's modulus for the fibers. It is shown that possible effects due to stress-induced changes in electron-delocalization in this fully conjugated polymer are negligible and the principal contributions to the bond frequency shifts is due to bond anharmonicity. Models which assume that the entire effect is due to bond anharmonicity produce calculated dependencies of V(C=C) and V(C triple bond C) upon fractional elongation which are in good agreement with that observed. (Author)
Journal of Chemical Physics, Jul 1, 1983
Journal of Polymer Science Part B, Aug 1, 1993
The thermal properties of perfluorocarbonsulfonic acid ionomer films cast from solution and their... more The thermal properties of perfluorocarbonsulfonic acid ionomer films cast from solution and their temperature-dependent far infrared spectra have been investigated. In addition to the endotherms and spectral changes associated with the loss of solvent as the films were heated, a significant exotherm has been observed and assigned to the relaxation associated with rearrangements resulting in partially crystallized phases in insoluble thermally treated membranes. 0 1993 John Wiley & Sons, Inc.
Microporous and Mesoporous Materials, May 1, 2013
A composite of a silica aerogel and a copolymer of chitosan and polyaniline (chitaline) with Au o... more A composite of a silica aerogel and a copolymer of chitosan and polyaniline (chitaline) with Au or Ag nanoparticles was prepared by a surfactant-free sol-gel process. By grafting polyaniline on the chitosan backbones, the copolymer chitaline was synthesized, which is soluble in aqueous solution. It can be combined with silica gels to form aerogel composites, the specific surface areas of chitaline/silica aerogels are over 650 m 2 /g, with densities low to 0.09 g/cm 3. Upon protonic doping, the chitaline/silica aerogels conductivity rises from less than 10 À8 to 10 À4 S/cm. This kind of chitaline possesses primary amines in the backbone structure that can bind metal ions, and the reduction potential of chitaline was tested lower to 0.735 V, which can easily reduce high potential ions such as Au(III) and Ag(I) to form nanostructured metal particles. And the reduced nanoparticles were observed homogenously dispersed in the aerogels.
Journal of Chemical Physics, Jun 1, 1977
The configurational entropy theory of glass formation is used to derive the composition dependenc... more The configurational entropy theory of glass formation is used to derive the composition dependence of the glass transition temperature (Tg) and of supercooled liquid transport properties for binary mixtures which obey the laws of regular solutions. The relations between expressions derived subject to specified approximations and known empirical equations are shown, and the parameters of the latter are thereby identified with defined measurable quantities. The predicted compostion dependence of Tg is compared with experimental data from binary mixtures with satisfactory agreement.
MRS Proceedings, 2005
By employing novel hybrid silica/functional polymer aerogels, control of the course of chemical r... more By employing novel hybrid silica/functional polymer aerogels, control of the course of chemical reactions between reactants confined inside of the aerogels with reactants whose access to the confinement domain is controlled by diffusion has been explored. Thus, monolithic silica/biopolymer hybrid aerogels have been synthesized with coordinated metal ions that can react with amino acids, such as L-cysteine, that are provided externally in a surrounding solution. Metal ions, such as Au(III), that can react in solution with the amino acid to produce one set of products under a given set of stoichiometric or concentration conditions, and a different set of products under a second set of conditions, were selected for incorporation into the aerogel. It was discovered that the course of the reaction could be changed by spatial confinement of the reaction domain in the aerogel. For example, in the case of Au(III) and L-cysteine, the Au(III) ions are confined in nanoscale domains, and when they are reacted with the amino acid, the nature of the reaction products is controlled by diffusion of the L-cysteine into the domains. Exploration of these and related phenomena will be presented.
Journal of Non-crystalline Solids, Aug 1, 1981
ABSTRACT
Inorganic Chemistry, Jun 1, 1969
Chemischer Informationsdienst, Apr 13, 1976
Proceedings of SPIE, Nov 1, 1991
Dried sol-gel silicate materials containing metal ions (2Th02-2M20-96Si02; where M = Na, K, or Cs... more Dried sol-gel silicate materials containing metal ions (2Th02-2M20-96Si02; where M = Na, K, or Cs) were ion-exchanged at 25 °C in selected regions using microelectronic masking methods and ionic solutions. After heat densification, the compositions and properties of the exchanged and unexchanged regions of the gel were investigated by microscopy, SEM-EDAX, and micro- Raman spectroscopy. Comparison of the spectra with those of melt-quench glasses of the same stoichiometries, exchanged identically, shows the effectiveness of the gel exchange.
Bulletin of The Korean Chemical Society, 1988
Hydrazine is the simplest diamine containing two lone pair of electrons. It forms variety of comp... more Hydrazine is the simplest diamine containing two lone pair of electrons. It forms variety of compounds with more number of carboxylic acids, such as simple aliphatic mono and di carboxylic acids 1,2 aromatic mono and di carboxylic acids 3,4 tri and tetra carboxylic acids 5,6 , which have been reported in the literature. Many bis-hydrazine and hydrazinium metal carboxylates are used as precursors for metal oxides and mixed metal oxides 7-15. Though studies have been done on 4-acetamido benzoate synthesis of lanthanide coordination polymers using 4-acetamido benzoic acid and various modes of coordination of 4-acetamido benzoate (monodentate, chelating and multidentate bridging nature) 16-20 , a detailed study of transition metal complexes of isomeric acetamido benzoic acids in the presence of hydrazine has not been attempted so far. In this paper, we report the synthesis, spectral and thermal studies of some transition metal complexes of 2-acetamido, 3-acetamido and 4-acetamido benzoates with hydrazine. The
Journal of the American Chemical Society, Nov 1, 1997
Journal of Chemical Physics, Sep 15, 1984
Soluble substituted polydiacetylenes (a class of conjugated polymers) undergo a variety of phase ... more Soluble substituted polydiacetylenes (a class of conjugated polymers) undergo a variety of phase transitions signaled by color changes. The particular example we studied, poly-3BCMU in chloroform/hexane solutions, exhibits a low temperature blue phase and a high temperature yellow phase. The visible and resonance Raman spectra of both the blue and yellow forms dispaly coexisting conjugation length regimes of 6, 10, and >20 monomers. However, we find that the relative proportions of these regimes indicates that that are three, rather than two, different phases: an equilibrium blue phase, an equilibrium yellow phase, and a metastable blue phase containing short conjugation lengths quenched in. It is this last phase which we characterize as glass-like.
Chemical Physics Letters, Nov 1, 1970
Fnr infrared bands for the motion of Li +. Naf and Csf in the field of side groups and paraffinic... more Fnr infrared bands for the motion of Li +. Naf and Csf in the field of side groups and paraffinic elements of ethylene-methncrylnte ionic copolymers. and a preliminary evaluation of the force field for the vibrations of those ions arc reported.
Journal of Catalysis, Aug 1, 1985
Abstract Ru(III) ions have been incorporated in the domains of sulfonated linear polystyrene (PSS... more Abstract Ru(III) ions have been incorporated in the domains of sulfonated linear polystyrene (PSSA) as a dispersion medium to form PSSA-Ru(III) films through an ion-exchange process. The chemical reactivities of PSSA-Ru(III) films have been investigated by reacting the ruthenium sites with CO, H2, O2, CH3OH, and C2H5OH under mud conditions. The reactions of PSSA-Ru(III) films with CO (400 Torr) in the temperature range 25–186 °C resulted in four different Ru carbonyl species, which were characterized by their infrared spectra. Treatment of PSSA-Ru(III) films with hydrogen (400 Torr) at 150 °C produced ruthenium hydride species, which were confirmed by identifying the corresponding ruthenium deutendes. Also, HD exchange on benzene rings of the polystyrene backbone was found to occur during the reaction of PSSA-Ru(III) films with D2. The reactions of aqueous methanol and ethanol with PSSA-Ru(III) films produced ruthenium carbonyl species, but there was no evidence of the formation of ruthenium hydride or ruthenium formyl groups in the infrared spectra. Static Fischer-Tropsch type reactions of PSSA-Ru(III) powder with CO (300 Torr) and H2 (300 Torr) at 150 °C showed the formation of various aliphatic hydrocarbons, oxygen-containing hydrocarbon compounds, and CO2 in the mass and infrared spectra.
The Journal of Physical Chemistry, Nov 1, 1977
Publication costs assisted by Brown University and the Union Carbide Corporation Far-infrared ion... more Publication costs assisted by Brown University and the Union Carbide Corporation Far-infrared ion motion bands have been observed and assigned in the spectra of dry synthetic zeolites X and Y containing Li' , Na+, K+, Rb' , Cs+, Ag+, Ca2+, Sr2+, and Ba2+ cations. The site I' and site I1 cation vibrational bands overlap and form the strongest feature in the spectra of samples exchanged with monovalent ions. The site I cation band appears at lower frequency than the site I1 envelope in these samples, but in divalent ion exchanged zeolites the opposite order occurs. A very low frequency site I11 cation band, typical of monovalent X zeolites, has been observed in CsY. For a given cation, the frequency on X is higher than on Y due to the higher framework charge of X zeolites. The vibrational frequencies also follow an approximate m-1/2 dependence for the two types of cation and the two forms of the zeolite. Solvation of the monovalent zeolites with H20, THF, Me2S0, pyridine, and CH2C12 results in the appearance of a new band at higher frequency than the ion-framework modes which concurrently diminish in intensity, especially the site I11 band. The high frequency band is due to ion motion in a solvation shell which is unsymmetric at low hydration levels and at all solvation levels with organic adsorbates. In addition to a cation mass dependence, the ion-solvent frequencies are also dependent on the adsorbent's effective dielectric constant which is greater in X than Y zeolites. Increasing solvation shifts the ion-framework vibrations to lower frequency, but this shift with the organic adsorbates is primarily an indirect effect due to solvent delocalizing the framework charge. The implications of the cation vibrational frequencies for the mechanism of ionic conduction are considered in terms of a simple free-ion model. Ion transport in Y zeolites which have a large number of vacant cation sites so that each jump may be considered an independent event is adequately explained by this model, but ion transport in X zeolites is best interpreted in terms of cooperative effects.
Journal of the American Chemical Society, Apr 1, 1970
The infrared spectrum of tetrahydrofuran solutions of a number of alkali metal salts has been obs... more The infrared spectrum of tetrahydrofuran solutions of a number of alkali metal salts has been observed between 90 and 600 cm-1. Some measurements were made in other solvents (dimethyl sulfoxide, pyridine, and piperidine). In every case, a band was observed which could be associated with alkali ion vibration. The frequency shows a dependence upon anion in THF as well as a dependence upon solvent. The effect of pressure to 20 kbar, frequency shift with Lif isotope substitution, the variation of band intensity with concentration, and Raman spectra were studied for selected salts in THF. The results suggest that the infrared band arises from motion in the solutions which is similar to that which occurs on the excitation of a highly localized phonon at an impurity center in crystals. The motion may be approximated as the alkali ion vibrating in a cage, under the influence of electrostatic and repulsion forces. The anion is a cage component in THF solutions while only solvent molecules are involved in DMSO. The force constant for the net force resisting the displacement of the alkali ion was calculated from the experimental results. Force constants of the same magnitude arise from a solution model in which the electrostatic terms are expressed on a molecular basis and repulsion by exponential terms.
Journal of Catalysis, Jun 1, 1985
Abstract The reduction and subsequent oxidation of Ag(I)-containing films of polyfluorocarbon sul... more Abstract The reduction and subsequent oxidation of Ag(I)-containing films of polyfluorocarbon sulfonic acid (Nafion) have been studied spectroscopically, electron microscopically, and kinetically. The ultraviolet-visible and infrared spectral features observed in situ during these processes are interpreted in terms of the formation of Ag particles and their surface oxidation upon exposure to air or oxygen. The particle size distributions are narrow and give average diameters of 20–30 A for various reductive and oxidative treatments. The kinetics of the oxidation, which were followed by observing the growth of silver-silver oxide charge transfer absorption at 370 nm, are analyzed in terms of two parallel reactions. The first, postulated to give atomically adsorbed oxygen, is about 10 times faster than the postulated slower formation of molecularly adsorbed oxygen.
Abstract The Raman spectra of 10B, 11B, 16O, 18O, and mixed isotopic compositions of B2O3 (gl) ar... more Abstract The Raman spectra of 10B, 11B, 16O, 18O, and mixed isotopic compositions of B2O3 (gl) are reported. The 808 cm−1 band assigned to the boroxol ring structure is found to shift upon oxygen isotope substitution, and not to depend on the boron mass. It is replaced by four band, in the intensity ratio 1 : 3 : 3 : 1, in the case of the 50% 16O-50% 18O-containing material. On the other hand, the frequencies of other principal bands depend on the masses of both boron and oxygen. The about 1260 cm−1 band, in particular, depends on the masses of both, and shifts without broadening upon partial oxygen substitution. The analysis of these data shows that both a local unit, behaving as predicted for the boroxol ring, and a continuous random network of connecting bonds are manifested in the spectra.
Unknown eBooks, Dec 19, 1975
Abstract : The application of a tensile stress to a macroscopic monocrystalline fiber of a polydi... more Abstract : The application of a tensile stress to a macroscopic monocrystalline fiber of a polydiacetylene, an extended-chain polymer, causes the Raman-observed C triple bond C and C=C in-chain vibrational frequencies to decrease linearly with elongation. The polymer studied, poly-HDN, results from the solid-state polymerization of R-C triple bond C triple bond C-R where R = CH2OCONHC6H5. This experimental relationship between the molecular bond (spectroscopic) effects and the macroscopic properties is analyzed by relating the bond moduli (force constants) and Young's modulus for the fibers. It is shown that possible effects due to stress-induced changes in electron-delocalization in this fully conjugated polymer are negligible and the principal contributions to the bond frequency shifts is due to bond anharmonicity. Models which assume that the entire effect is due to bond anharmonicity produce calculated dependencies of V(C=C) and V(C triple bond C) upon fractional elongation which are in good agreement with that observed. (Author)
Journal of Chemical Physics, Jul 1, 1983
Journal of Polymer Science Part B, Aug 1, 1993
The thermal properties of perfluorocarbonsulfonic acid ionomer films cast from solution and their... more The thermal properties of perfluorocarbonsulfonic acid ionomer films cast from solution and their temperature-dependent far infrared spectra have been investigated. In addition to the endotherms and spectral changes associated with the loss of solvent as the films were heated, a significant exotherm has been observed and assigned to the relaxation associated with rearrangements resulting in partially crystallized phases in insoluble thermally treated membranes. 0 1993 John Wiley & Sons, Inc.
Microporous and Mesoporous Materials, May 1, 2013
A composite of a silica aerogel and a copolymer of chitosan and polyaniline (chitaline) with Au o... more A composite of a silica aerogel and a copolymer of chitosan and polyaniline (chitaline) with Au or Ag nanoparticles was prepared by a surfactant-free sol-gel process. By grafting polyaniline on the chitosan backbones, the copolymer chitaline was synthesized, which is soluble in aqueous solution. It can be combined with silica gels to form aerogel composites, the specific surface areas of chitaline/silica aerogels are over 650 m 2 /g, with densities low to 0.09 g/cm 3. Upon protonic doping, the chitaline/silica aerogels conductivity rises from less than 10 À8 to 10 À4 S/cm. This kind of chitaline possesses primary amines in the backbone structure that can bind metal ions, and the reduction potential of chitaline was tested lower to 0.735 V, which can easily reduce high potential ions such as Au(III) and Ag(I) to form nanostructured metal particles. And the reduced nanoparticles were observed homogenously dispersed in the aerogels.
Journal of Chemical Physics, Jun 1, 1977
The configurational entropy theory of glass formation is used to derive the composition dependenc... more The configurational entropy theory of glass formation is used to derive the composition dependence of the glass transition temperature (Tg) and of supercooled liquid transport properties for binary mixtures which obey the laws of regular solutions. The relations between expressions derived subject to specified approximations and known empirical equations are shown, and the parameters of the latter are thereby identified with defined measurable quantities. The predicted compostion dependence of Tg is compared with experimental data from binary mixtures with satisfactory agreement.
MRS Proceedings, 2005
By employing novel hybrid silica/functional polymer aerogels, control of the course of chemical r... more By employing novel hybrid silica/functional polymer aerogels, control of the course of chemical reactions between reactants confined inside of the aerogels with reactants whose access to the confinement domain is controlled by diffusion has been explored. Thus, monolithic silica/biopolymer hybrid aerogels have been synthesized with coordinated metal ions that can react with amino acids, such as L-cysteine, that are provided externally in a surrounding solution. Metal ions, such as Au(III), that can react in solution with the amino acid to produce one set of products under a given set of stoichiometric or concentration conditions, and a different set of products under a second set of conditions, were selected for incorporation into the aerogel. It was discovered that the course of the reaction could be changed by spatial confinement of the reaction domain in the aerogel. For example, in the case of Au(III) and L-cysteine, the Au(III) ions are confined in nanoscale domains, and when they are reacted with the amino acid, the nature of the reaction products is controlled by diffusion of the L-cysteine into the domains. Exploration of these and related phenomena will be presented.
Journal of Non-crystalline Solids, Aug 1, 1981
ABSTRACT
Inorganic Chemistry, Jun 1, 1969
Chemischer Informationsdienst, Apr 13, 1976
Proceedings of SPIE, Nov 1, 1991
Dried sol-gel silicate materials containing metal ions (2Th02-2M20-96Si02; where M = Na, K, or Cs... more Dried sol-gel silicate materials containing metal ions (2Th02-2M20-96Si02; where M = Na, K, or Cs) were ion-exchanged at 25 °C in selected regions using microelectronic masking methods and ionic solutions. After heat densification, the compositions and properties of the exchanged and unexchanged regions of the gel were investigated by microscopy, SEM-EDAX, and micro- Raman spectroscopy. Comparison of the spectra with those of melt-quench glasses of the same stoichiometries, exchanged identically, shows the effectiveness of the gel exchange.
Bulletin of The Korean Chemical Society, 1988
Hydrazine is the simplest diamine containing two lone pair of electrons. It forms variety of comp... more Hydrazine is the simplest diamine containing two lone pair of electrons. It forms variety of compounds with more number of carboxylic acids, such as simple aliphatic mono and di carboxylic acids 1,2 aromatic mono and di carboxylic acids 3,4 tri and tetra carboxylic acids 5,6 , which have been reported in the literature. Many bis-hydrazine and hydrazinium metal carboxylates are used as precursors for metal oxides and mixed metal oxides 7-15. Though studies have been done on 4-acetamido benzoate synthesis of lanthanide coordination polymers using 4-acetamido benzoic acid and various modes of coordination of 4-acetamido benzoate (monodentate, chelating and multidentate bridging nature) 16-20 , a detailed study of transition metal complexes of isomeric acetamido benzoic acids in the presence of hydrazine has not been attempted so far. In this paper, we report the synthesis, spectral and thermal studies of some transition metal complexes of 2-acetamido, 3-acetamido and 4-acetamido benzoates with hydrazine. The
Journal of the American Chemical Society, Nov 1, 1997
Journal of Chemical Physics, Sep 15, 1984
Soluble substituted polydiacetylenes (a class of conjugated polymers) undergo a variety of phase ... more Soluble substituted polydiacetylenes (a class of conjugated polymers) undergo a variety of phase transitions signaled by color changes. The particular example we studied, poly-3BCMU in chloroform/hexane solutions, exhibits a low temperature blue phase and a high temperature yellow phase. The visible and resonance Raman spectra of both the blue and yellow forms dispaly coexisting conjugation length regimes of 6, 10, and >20 monomers. However, we find that the relative proportions of these regimes indicates that that are three, rather than two, different phases: an equilibrium blue phase, an equilibrium yellow phase, and a metastable blue phase containing short conjugation lengths quenched in. It is this last phase which we characterize as glass-like.
Chemical Physics Letters, Nov 1, 1970
Fnr infrared bands for the motion of Li +. Naf and Csf in the field of side groups and paraffinic... more Fnr infrared bands for the motion of Li +. Naf and Csf in the field of side groups and paraffinic elements of ethylene-methncrylnte ionic copolymers. and a preliminary evaluation of the force field for the vibrations of those ions arc reported.
Journal of Catalysis, Aug 1, 1985
Abstract Ru(III) ions have been incorporated in the domains of sulfonated linear polystyrene (PSS... more Abstract Ru(III) ions have been incorporated in the domains of sulfonated linear polystyrene (PSSA) as a dispersion medium to form PSSA-Ru(III) films through an ion-exchange process. The chemical reactivities of PSSA-Ru(III) films have been investigated by reacting the ruthenium sites with CO, H2, O2, CH3OH, and C2H5OH under mud conditions. The reactions of PSSA-Ru(III) films with CO (400 Torr) in the temperature range 25–186 °C resulted in four different Ru carbonyl species, which were characterized by their infrared spectra. Treatment of PSSA-Ru(III) films with hydrogen (400 Torr) at 150 °C produced ruthenium hydride species, which were confirmed by identifying the corresponding ruthenium deutendes. Also, HD exchange on benzene rings of the polystyrene backbone was found to occur during the reaction of PSSA-Ru(III) films with D2. The reactions of aqueous methanol and ethanol with PSSA-Ru(III) films produced ruthenium carbonyl species, but there was no evidence of the formation of ruthenium hydride or ruthenium formyl groups in the infrared spectra. Static Fischer-Tropsch type reactions of PSSA-Ru(III) powder with CO (300 Torr) and H2 (300 Torr) at 150 °C showed the formation of various aliphatic hydrocarbons, oxygen-containing hydrocarbon compounds, and CO2 in the mass and infrared spectra.