Dielectric spectroscopy was employed to study the effects of water on primary alpha -relaxation and secondary beta xylitol. The measurements were made anhydrous xylitol mixtures with three different concentrations over a temperature range from 173 K 293 K. speeds up increasing concentration in xylitol, whereas rate is essentially unchanged. Some systematic differences behavior for observed. Our findings confirm all observations Nozaki et al. [J. Non-Cryst. Solids 307, 349 (2002)]]...

Modifications of integrated calibration method (ICM) in its basic variant and complementary dilution version (CDM) were adapted to multi-component (MC) analysis obtain novel approaches improving the accuracy analytical results. Methods developed conceptually their performance was assessed on basis polycyclic aromatic hydrocarbons (PAHs) determination air samples. The natural (thuja needles) synthetic (polymer) materials combusted simulating fires or home users’ combustion. Analytical for EPA...

Broadband dielectric spectroscopy is employed to investigate the non-Debye relaxation behavior in a dendrimeric alkyd resin. From temperature-dependent measurements at ambient pressure, we found very broad distribution of times. This attributed complex geometrical topology molecule. However, compression significantly reduces character response; thus, pressure induces dynamic homogeneity

Dielectric loss spectra are reported for $\ensuremath{\alpha}$-tocopherol acetate (an isomer of vitamin E) in the supercooled and glassy states. The $\ensuremath{\alpha}$-relaxation times, ${\ensuremath{\tau}}_{\ensuremath{\alpha}}$, measured over a 190\ifmmode^\circ\else\textdegree\fi{} range temperatures, $T$, at pressures, $P$, up to $400\phantom{\rule{0.3em}{0ex}}\mathrm{MPa}$ can be expressed as single function $T{V}^{3.9}$ ($V$ is specific volume, herein $T$ $P$). At ambient pressure,...

The thermogravimetric analysis was applied for indication of the thermal stability polyurethane-rubber composites received from polyurethane and rubber waste. results show that decomposition granulate depends on speed heating. It starts within temperature range 320°C to 360°C is completed at 500°C 550°C. evaporation small-molecular substances probably takes place below 300°C. At temperatures above 320°C, two-stage waste observed. low corresponds natural (NR) while high styrene-butadiene...

Broadband dielectric spectroscopy was used to study the relaxation dynamics in bis-5-hydroxypentylphthalate (BHPP) under both isobaric and isothermal conditions. The exhibit complex behavior, arising from hydrogen bonding BHPP. At ambient pressure above glass transition temperature T(g), spectrum shows a broad structural peak with prominent excess wing toward higher frequencies. As is decreased below transforms into two distinct peaks, having Arrhenius behavior activation energies equal 58.8...

The X-ray structure, theoretical calculation, Hirshfeld surfaces analysis, IR and Raman spectra of fluoranthene acenaphthene were reported. Acenaphthene crystallizes in the orthorhombic crystal system space group P21ma, with parameters a = 7.2053 (9) ?, b 13.9800 (15) c 8.2638 (8) Z 4 V 832.41 (16) ?3. In turn, grown crystals are monoclinic P21/n. unit cell 18.3490 (2) 6.2273 (5) 19.8610 ? 109.787 (13)?, 8 volume is 2135.50 (4) Theoretical calculations title compounds isolated molecule have...

The results presented give the evidence for quasicritical, pretransitional behavior of dielectric properties in isotropic phase a rodlike nematic liquid crystal with transverse permanent dipole moment. Studies were conducted 2-cyano-4-pentylbiphenyl 4-(trans-4-pentylcyclohexyl) benzoate, focusing on static-and ionic-dominated low-frequency (LF) regions. For static permittivity [epsilon(')(T)] application derivative analysis revealed anomaly associated specific heat exponent alpha...

Abstract The NMR spectroscopy was used to determine a structure and physicochemical properties of liposomes prepared from L ‐α‐phosphatidylcholine dipalmitoyl (DPPC) by the modified reverse‐phase evaporation method (mREV). 31 P‐NMR study liposome in temperature range 340K 350K allowed us suggest that single‐bilayered has been obtained. Transmission electron micrographs (TEM) showed vesicles, obtained with use (mREV) method, were spherical shape majority they less than 100 nm diameter.

The aim of the investigation was dynamic thermo-mechanical analysis (DMTA) study polyurethane-rubber composites obtained from used polymer products. Polyols in glycolysis process semi-rigid polyurethane foams, hardened by diphenylmethane 4,4′-diisocyanate (MDI) and rubber granules mechanical granulation car tyres were to receive composites. On basis DMTA spectra glass transition temperature Tg determined. loss module E′′ allowed us observe two relaxation processes for polyurethane-waste α –...

Abstract The description of polymer relaxation proprieties is the way to characterize influence structure on its useful stability and resistance. To perform physicochemical profiles polymers synthesis investigation model compounds was required. instrumental methods such as NMR, FTIR, dielectric spectroscopy were used. results experiments allowed us improve technology processes extension range their usage. Moreover obtained more stable resistant degradation. acquire profile properties linear,...

The EPR spectroscopy was used to determine the structure and physicochemical properties of liposomes prepared from L-α-phosphatidylcholine dipalmitoyl (DPPC) by modified reverse-phase evaporation method (mREV). study carried out in temperature range 297 K 340 i.e. below above phase transition TC DPPC. On basis spectra spin marker 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) incorporated into liposome, parameter f determined. TEMPO dissolves easily water fluid lamellar smectic...

The EPR spectroscopy was used to determine the structure and physicochemical properties of liposomes prepared from L-α-phosphatidylcholine dipalmitoyl (DPPC) by modified reverse-phase evaporation method (mREV). study carried out in temperature range 297 K 340 i.e. below above phase transition T C DPPC. On basis spectra spin marker 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) incorporated into liposome, parameter f determined. TEMPO dissolves easily water fluid lamellar smectic...

Abstract Sumary: One of the ways polymer waste management is its chemical modification. Waste polystyrene foam (EPS) and virgin (VPS) as reference material were converted into polymeric flocculants by reactions. most popular widely used procedures to follow flocculation kinetics monitoring turbidity a function polyelectrolyte dosage. The application obtained products caused significant decrease studied solutions. successfully in treatment water. A colloid system composed ferrum(III)...

Some oligoesters were synthesized in order to study changes of the useful properties hyper-branched unsaturated polyesters. The determination polymer relaxation allows for characterization their structure. Useful polymers such as stability and persistence depend on aim investigation was obtain model with low molecular weight by spectroscopic dynamic mechanical thermal analysis (DMTA) methods. synthesis performed use ethylene glycol mixture maleic anhydride phthalic acid which allowed us...

The determination of the physicochemical properties polyelectrolytes in water solution has fundamental importance for description their possible application. Gel permeation chromatography (GPC), dynamic light scattering (DLS) and viscosimetry studies were performed this goal. obtained from polystyrene waste. Waste foam (EPS) as reference material was converted into polymeric flocculants (NaEPSS) chemical reactions.1-3 Products with determined molecular weight number sulphonic group per...

Abstract The study of polymer properties requires the synthesis and analysis simple model compounds. In this work suitable oligoesters were used for purpose. investigation allows us to describe physicochemical utility i.e. stability resistance linear, branched dendrite polyesters. To achieve aim synthesized their described. structure was confirmed with use NMR, FTIR spectroscopy elemental analysis. A detailed relaxation using broadband dielectric Dynamic Mechanical Thermal Analysis (DMTA)...

Abstract Sumary: One of the ways polymer waste management is its chemical modification. Waste polystyrene foam (EPS) and virgin (VPS) as reference material were converted into polymeric flocculants by reactions. most popular widely used procedures to follow flocculation kinetics monitoring turbidity a function polyelectrolyte dosage. The application obtained products caused significant decrease studied solutions. successfully in treatment water. A colloid system composed ferrum(III)...

Used polymer plastics have high fuel values (approximately 40 MJ/kg for polyolefines). Therefore, they constitute perfect energy materials. Thermodestruction of used products and wastes on specialized installations seems to be a long-term method manage this group in chemical recycling with the destination obtain ingredients. Application technology allows reduction quantity municipal waste. This enables also valuable components. In Department Environment Chemistry Technology Institute at...

Purpose: This publication provides a description of RDC Glokor’s own research into the effectiveness lactic fermentation process lactose, acid concentration and polylactide (PLA) production by ring-opening polymerization obtained from condensation two molecules acid. Furthermore, this sets out to determine potential applications PLA as commercial material with selection thermal properties. Design/methodology/approach: In described works, was used in which lactose is converted participation...