LC-NMR Analysis of Phenylsilane Polymers
Pinkas, Jiří; Merna, J.; Sýkora, Jan
2011 - English We report the analysis of dehydrocoupling polymerization reactions of phenylsilane via on-flow LC-NMR experiment. The successful separation was achieved by isocratic elution of acetonitrile and aceton (80:20). The separation was solely monitored by 1H NMR detection. The properties of the polymeric product depend on the catalytical system. The products can differ in the molar weight distribution, degree of branching and amount of cyclic and rearranged products. In our particular cases, the weight average molar mass (Mw) varies from several silane units up to 4100 g.mol-1. The branching of polysilanes is monitored by 29Si{1H} INEPT experiment with the polarization transfer from the ortho hydrogen (J~7 Hz). The connectivity within branched unit was established via 1H à 29Si-29Si INEPT-INADEQUATE experiment. Keywords: phenylsilanes; LC-NMR; 29Si NMR Available at various institutes of the ASCR LC-NMR Analysis of Phenylsilane Polymers

We report the analysis of dehydrocoupling polymerization reactions of phenylsilane via on-flow LC-NMR experiment. The successful separation was achieved by isocratic elution of acetonitrile and aceton ...

Pinkas, Jiří; Merna, J.; Sýkora, Jan
Ústav chemických procesů, 2011

Density and Viscosity of Alkylammonium-Based Ionic Liquids
Machanová, Karolina; Sedláková, Zuzana; Boisset, A.; Bendová, Magdalena; Jacquemin, J.; Aim, Karel
2011 - English Keywords: ionic liquids; thermophysical properties Available at various institutes of the ASCR Density and Viscosity of Alkylammonium-Based Ionic Liquids

Machanová, Karolina; Sedláková, Zuzana; Boisset, A.; Bendová, Magdalena; Jacquemin, J.; Aim, Karel
Ústav chemických procesů, 2011

Splitting and/or Formation of Chemical Bonds. Insights from Momentum Space
Ponec, Robert; Cooper, D.L.
2011 - English Keywords: domain averaged fermi holes; momentum space; chemical bonding Available at various institutes of the ASCR Splitting and/or Formation of Chemical Bonds. Insights from Momentum Space

Ponec, Robert; Cooper, D.L.
Ústav chemických procesů, 2011

High-Pressure CO2 as a Green Solvent for Extraction, Reaction, Particle Formation and Others Processes
Sajfrtová, Marie; Sovová, Helena
2011 - English Keywords: organic solvents; supercritical fluids; extraction Available at various institutes of the ASCR High-Pressure CO2 as a Green Solvent for Extraction, Reaction, Particle Formation and Others Processes

Sajfrtová, Marie; Sovová, Helena
Ústav chemických procesů, 2011

Size-Dependent Rate Constant of Chemical Reactions in Nanoscale Particles
Levdansky, V.V.; Smolík, Jiří; Ždímal, Vladimír; Moravec, Pavel
2011 - English It is known that many processes occurring in heterogeneous systems with nanoscale objects are characterized by some specific features due to size dependence of parameters describing processes in question. This can in particular affect nanoparticle formation. Some problems related to the trapping of impurity molecules by nanoparticles were considered in (Levdansky et al., 2009). Here we study the influence of the size effect on chemical reactions inside nanoparticles. Keywords: size effect; nanoparticles; chemical reactions Available at various institutes of the ASCR Size-Dependent Rate Constant of Chemical Reactions in Nanoscale Particles

It is known that many processes occurring in heterogeneous systems with nanoscale objects are characterized by some specific features due to size dependence of parameters describing processes in ...

Levdansky, V.V.; Smolík, Jiří; Ždímal, Vladimír; Moravec, Pavel
Ústav chemických procesů, 2011

Influence of Size Effects on Homogeneous Nucleation Inside Nanoparticles
Levdansky, V.V.; Smolík, Jiří; Ždímal, Vladimír; Moravec, Pavel
2011 - English It is known that many physicochemical processes in aerosol systems with nanoscale particles and in nanoparticles themselves depend on the particle size. The influence of size dependence of the condensation coefficient on gas-phase nucleation was discussed in (Levdansky et al., 2010). Some problems related to nucleation in confined space, in particular the depletion effect of the ambient phase, were considered in (Kožíšek et al., 2011; Schmelzer and Abyzov, 2011). Here we study the size effects in homogeneous nucleation inside nanoparticles related to size dependence of the effective rate constant for the attachment of monomers to the critical cluster. Keywords: size effect; nanoparticles; chemical reactions Available at various institutes of the ASCR Influence of Size Effects on Homogeneous Nucleation Inside Nanoparticles

It is known that many physicochemical processes in aerosol systems with nanoscale particles and in nanoparticles themselves depend on the particle size. The influence of size dependence of the ...

Levdansky, V.V.; Smolík, Jiří; Ždímal, Vladimír; Moravec, Pavel
Ústav chemických procesů, 2011

AWS Viscometry – Principles and Applications
Wein, Ondřej
2011 - English Quantitative identification of Apparent wall slip (AWS) effect, accompanying the flow of colloidal dispersions in confined geometries, requires a specific modification of common viscometric methods. Essential distinction between common and AWS viscometry is outlined – including theoretical background, calibration, data acquisition, and downstream data treatment – and demonstrated for a class of rotational viscometers. Keywords: AWS viscometry; adgr effects; inertia effects Available at various institutes of the ASCR AWS Viscometry – Principles and Applications

Quantitative identification of Apparent wall slip (AWS) effect, accompanying the flow of colloidal dispersions in confined geometries, requires a specific modification of common viscometric methods. ...

Wein, Ondřej
Ústav chemických procesů, 2011

Vapor–Liquid Equilibrium in Diluted Polymer + Toluene Systems
Bogdanić, Grozdana; Wichterle, Ivan
2011 - English Vapor–liquid equilibrium data were determined for five polymer plus toluene systems at isothermal conditions between 60 and 100 oC. Polymers comprise copolymers and terpolymers of octadecyl acrylate, acrylic acid, styrene, and 1-vinyl-2-pyrrolidone because of their practical importance as flow improvers for crude oil and/or derivatives. All-glass micro-ebulliometer with circulation of liquid phase was used for measurement of total pressure over polymer + toluene mixtures. Two predictive group contribution models (the Entropic–Free Volume and the Group Contribution–Flory) were applied to estimate phase behavior of two polymer solutions; good agreement with experimental data was achieved. Keywords: polymer and toluene systems; experimental data; vapor–liquid equilibrium data Available at various institutes of the ASCR Vapor–Liquid Equilibrium in Diluted Polymer + Toluene Systems

Vapor–liquid equilibrium data were determined for five polymer plus toluene systems at isothermal conditions between 60 and 100 oC. Polymers comprise copolymers and terpolymers of octadecyl acrylate, ...

Bogdanić, Grozdana; Wichterle, Ivan
Ústav chemických procesů, 2011

29Si NMR Phenylsilane Polymer Analysis
Pinkas, Jiří; Blechta, Vratislav; Karban, Jindřich; Sýkora, Jan
2011 - English Here we focus on the analysis od dehydrocoupling polymerization reactions of phenylsilane. the molar mass distribution depends on the catalytic system and can be easily monitored by on-flow LC-NMR experiment. Keywords: polymer analysis; 29Si NMR; hydrogen Available at various institutes of the ASCR 29Si NMR Phenylsilane Polymer Analysis

Here we focus on the analysis od dehydrocoupling polymerization reactions of phenylsilane. the molar mass distribution depends on the catalytic system and can be easily monitored by on-flow LC-NMR ...

Pinkas, Jiří; Blechta, Vratislav; Karban, Jindřich; Sýkora, Jan
Ústav chemických procesů, 2011

Molecular Dynamics Simulations of the Liquid Surface of Imidazolium-based [Tf2N-] Ionic Liquids.
Lísal, Martin
2011 - English Keywords: molecular dynamics simulation; ionic liquids Available at various institutes of the ASCR Molecular Dynamics Simulations of the Liquid Surface of Imidazolium-based [Tf2N-] Ionic Liquids.

Lísal, Martin
Ústav chemických procesů, 2011