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Several Temperatures (several + temperature)
Selected AbstractsCarotenoid Content and Physicochemical and Sensory Characteristics of Carrot Chips Deep-Fried in Different Oils at Several TemperaturesJOURNAL OF FOOD SCIENCE, Issue 9 2001A. Sulaeman ABSTRACT: The influence of deep-frying using different oils and temperatures on carotenoid content and physicochemical and sensory characteristics of carrot chips was investigated. Sliced carrots were steam-blanched, cooled, soaked in 0.2% sodium metabisulfite, and deep-fried in canola, palm, or partially hydrogenated soybean oil (PHSO) at 165, 175, or 185 °C. Frying temperature, but not oil, significantly (P < 0.05) affected the ,-carotene, ,-carotene, and total carotenoid contents. Oil type significantly (P < 0.05) influenced all color values. Increasing temperature lowered the redness value, which correlated with decreased carotenoid content, color darkening, and decreased hardness value. Trained panelists detected no differences among oil types in crispness, sweetness, odor, and acceptability. The best carrot-chip product was that fried in PHSO at 165 °C. [source] The influence of Pb-ion irradiation on melt-textured YBa2Cu3Ox crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2009I. M. Obaidat Abstract Melt-textured YBa2Cu3Ox crystals have been irradiated along the c -axis with 208Pb56+ ions corresponding to dose matching fields, B, = 0.5 T and B, = 2.0 T. Magnetization measurements were conducted along the ab plane of the samples. The strength of pinning sites was investigated by measuring magnetization hysterisis and the saturation remanent magnetization MR at several temperatures. We have found that the pinning strength was considerably enhanced after irradiation at both doses. Interestingly, the pinning strength at a Pb-ion irradiation which corresponds to the dose matching field B, = 0.5 T, was found to be significantly larger than that at the dose matching field B, = 2.0 T at all temperatures. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] An evaluation of the self-heating hazards of cerium(IV) nitrated treated towels using differential scanning calorimetry and thermogravimetric analysisFIRE AND MATERIALS, Issue 6 2007J. R. Hartman Abstract This study measured the Arrhenius kinetic parameters and heat of reaction using thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) for the combustion of untreated towels and towels treated with cerium(IV) nitrate. These parameters were used to calculate the self-heating parameters, M and P (Self-heating: Evaluating and Controlling the Hazard. Her Majesty's Stationery Office: London, 1984) and the critical pile sizes of the towels at several temperatures. The results from the TGA/DSC experiments support the conclusions by Beyler et al. (Fire and Materials 2005; 30:223,240) that the cerium(IV) nitrate treatment of towels significantly enhances the ignitability of the towels but that self-heating is not a hazard for normal temperature storage scenarios other than bulk storage. It was found that the kinetic reaction data measured by TGA and DSC are only useful for predicting the specific reaction hazard for materials stored above 100°C. A comparison of the self-heating parameters measured by oven and kinetic reaction data methods for a number of materials suggests that the kinetic reaction data overestimate the critical pile size at temperatures below 100°C. In addition, it was found that the kinetic reaction data measured by TGA can be used to determine the relative self-heating hazards for modified materials. TGA testing with towels saturated with a 0.5 N solution of cerium(IV) nitrate (Ce(NO3)4) in a 2.0 N solution of nitric acid, a 2.0 N solution of sodium nitrate in 2.0 N nitric acid and simple 2.0 N nitric acid, showed that the sodium nitrate and nitric acid treated samples reacted at the same temperatures as the untreated towels, while cerium(IV) nitrate markedly reduced the reaction temperature. These tests clearly point to the importance of the cerium(IV) ion as an oxidizing agent. Thus, the TGA testing provided in a matter of days, insights that would have required months of oven testing. Copyright © 2006 John Wiley & Sons, Ltd. [source] Kinetic study of the reaction of dimethyl carbonate with trialkylaminesINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 4 2010Duane E. Weisshaar Quaternary ammonium compounds are produced worldwide in hundreds of millions of pound volume annually for a plethora of end-uses from fabric-care formulations to asphalt emulsifiers, typically from nongreen alkylating reagents. The kinetics of a reaction employing dimethyl carbonate (DMC) as a green alkylating agent was investigated using three trialkylamines (tributylamine, trihexylamine, and trioctylamine) at several temperatures. Arrhenius and Eyring analysis of the data showed that values of Ea (79 kJ/mol), ,H, (75 kJ/mol), and ,S, (220 J/(mol K)) were the same for all three amine reactants, consistent with a report that Ea is independent of alkyl chain length when the chain length is greater than three carbons. Although rates are significantly slower with DMC than with other alkylating reagents, the resulting methyl carbonate anion has advantages for clean anion metathesis, which is important for some applications, especially those involving ionic liquids. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 221,225, 2010 [source] Surface segregation in bimetallic nanoclusters: Geometric and thermodynamic effectsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4-5 2001Daniela S. Mainardi Abstract Nanocluster morphology (size, crystallographic faces, surface defects), coupled to thermodynamic driving forces, influence surface segregation phenomena. These geometric and thermodynamic effects are studied at several temperatures and overall compositions for Cu,Ni, Ag,Cu, and Ag,Rh. The bond order metal simulation model [Zhu, L.; DePristo, A. E. J Catal 1997, 167, 400] is used in Monte Carlo simulations to describe interatomic interactions. Nanoclusters from 110 to 729 atoms are arranged on stacks of layers corresponding to face-centered cubic crystals. The exposed surfaces are (111), (110), and (331) faces, and the overall composition of the clusters defined in terms of the segregating atoms ranges from 5 to 95%. The effect of surface steps on surface segregation is also investigated. It is found that as overall concentration increases, the effect of surface defects on segregation phenomena becomes more pronounced. The increase in the number of low coordination sites due to the presence of surface steps modifies the layer-by-layer composition profile, causing surface and inner sites in the proximity of the step to become occupied by the segregating atoms. The population on other surfaces becomes depleted, resulting in a lowered total surface segregation. These effects are more noticeable not only at high overall composition but also at high temperatures, especially for the less segregating system, Ag,Cu. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001 [source] PP/EVA blends: Mechanical properties and morphology.ADVANCES IN POLYMER TECHNOLOGY, Issue 4 2005Effect of compatibilizers on the impact behavior Abstract The mechanical properties of blends of isotactic polypropylene (PP) and poly[ethylene- co -(vinyl acetate)] (EVA) are studied under tension at several temperatures (from ,30°C to room temperature). The morphology and thermal properties are given attention at every stage of the stretching process. To improve the impact resistance of the blends, poly[propylene- graft -(maleic anhydride)] (PPMA) and hydroxylated EVA (EVAOH) are used as compatibilizers. The domain size of the dispersed phase decreases with compatibilizer content, improving the impact resistance of the blends. This is accompanied with changes in the morphology of such systems. © 2005 Wiley Periodicals, Inc. Adv Polym Techn 24: 241,252, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20050 [source] Mercury removal: a physicochemical study of metal interaction with natural materialsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 11 2009Leticia Carro Abstract BACKGROUND: Mercury is considered one of the most harmful heavy metals to the environment and human health, so recently remediation processes have been developed to eliminate this metal from wastewaters. Metal retention by natural polymers is a good alternative technique to remove heavy metals from solution. RESULTS: A screening of 25 potential mercury sorbents was carried out at three different pH values in order to find appropriate biomass to remove this metal from polluted waters. High sorption capacities were found for many of the materials studied. Four of these materials were selected for further detailed study. Kinetic studies showed short times to reach equilibrium. For S. muticum, sorption isotherms were obtained at several temperatures and a sorption enthalpy value was obtained. Desorption experiments were performed to determine the possibility for recycling of this brown alga. CONCLUSIONS: Different materials have been found to be potentially good adsorbents of mercury. A detailed study showed that S. muticum is an excellent material with a mercury uptake about 200 mg g,1. This brown alga has a fast kinetic process (80% of metal is removed from solution in 30 min), and very high metal uptake over a wide pH range, up to 92% elimination for pH values above 3,4. Copyright © 2009 Society of Chemical Industry [source] The Dielectric Property of Soybean Oil in Deep-Fat Frying and the Effect of FrequencyJOURNAL OF FOOD SCIENCE, Issue 3 2002C. Inoue ABSTRACT: : Suitability of the dielectric constant for real time and continuous evaluation of frying oil was investigated. Measurements of the dielectric capacitance, in the frequency range 1 kHz to 100 kHz, were made on soybean oil heated at several temperatures (180, 200, 220, and 240 °C) for a few d. Frequency dependence was also measured between 50 Hz and 30 MHz. The dielectric constant of the soybean oil increased with increase in the heating time, and was well correlated with acid value, density, and relative viscosity. Our equipment for measuring capacitance would be available for real time and continuous evaluation of frying oil quality in the food industry. [source] Crystallization Kinetics of Amorphous Lactose as a Function of Moisture Content Using Isothermal Differential Scanning CalorimetryJOURNAL OF FOOD SCIENCE, Issue 2 2000C. J. Kedward ABSTRACT: Isothermal differential scanning calorimetry (DSC) was used to study the crystallization kinetics of amorphous lactose at 3 moisture contents. Each sample was heated to several temperatures between Tg and Tm. After subtraction of an induction time, the Avrami equation was used to model the data and a Lauritzen-Hoffman like expression used to fit the crystallization rates between Tg and Tm. The highest Tm/Tg ratio and crystallization rate were observed for the sample containing the most moisture. Conversely the lowest Tm/Tg ratio and crystallization rate were observed for the sample containing the least moisture. Evidence for multiple transitions was seen. The Avrami equation may not be the best way to model such data. [source] Solid,liquid equilibrium of substrates and products of the enzymatic synthesis of ampicillinAICHE JOURNAL, Issue 6 2010Mônica Santana Abstract The solid,liquid equilibrium of precursors and products of the enzymatic synthesis of ampicillin (AMP) [6-aminopencillanic acid (6-APA) and D(,)phenylglycine (PG)] was investigated at different temperatures (283,298 K) and pHs (5.5,7.5). Solubility data were obtained using an analytical methodology. Equilibrium dissociation constants were experimentally measured at several temperatures for AMP, 6-APA, PG, and D(,)phenylglycine methyl ester. A model based on the simplified perturbed hard sphere theory proposed by Khoshkbarchi and Vera (Ind Eng Chem Res. 1996;35:4319-4327) was fitted against solubility data. The model could describe the water solubility behavior for AMP and PG as function of pH and temperature, but a bias was observed when fitting the model to the solubility of 6-APA. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Polarized Raman scattering and phase transition studies of n -diethylenediammonium monohydrogenmonophosphate dihydrateJOURNAL OF RAMAN SPECTROSCOPY, Issue 12 2006S. Elleuch Abstract Polarized Raman scattering studies at room temperature were carried out on N -diethylenediammonium monohydrogenmonophosphate dihydrate single crystal samples, abbreviated N -DDHP. An assignment of the normal modes is proposed based on group theory analysis and correlations with previous data reported for other homologous hydrogen-bonded systems. A careful analysis of the vibrational spectra shows that the assignment of the fundamental vibrational modes can be done based on phosphate, organic and water group vibrations. In addition, differential scanning calorimetry measurement and a Raman spectroscopic study at several temperatures in the range 100,300 K are presented. The occurrence of a low-temperature phase transition near 220 K is well evidenced. From the temperature-dependence behavior of some internal and external modes, this transition is interpreted by an order,disorder transition which involves the structural modifications of both anion and cation groups. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effect of temperature on the chromatographic retention of ionizable compounds.JOURNAL OF SEPARATION SCIENCE, JSS, Issue 6-7 2008Abstract We propose a general simple equation for accurately predicting the retention factors of ionizable compounds upon simultaneous changes in mobile phase pH and column temperature at a given hydroorganic solvent composition. Only four independent experiments provide the input data: retention factors measured in two pH buffered mobile phases at extreme acidic and basic pH values (e. g., at least ± 2 pH units far from the analyte pKa) and at two column temperatures. The equations, derived from the basic thermodynamics of the acid,base equilibria, additionally require the knowledge of the solute pKa and enthalpies of acid,base dissociation of both the solute and the buffer components in the hydroorganic solvent mixture. The performance of the predictive model is corroborated with the comparison between theoretical and experimental retention factors of several weak acids and bases of important pharmacological activity, in mobile phases containing different buffer solutions prepared in 25% w/w ACN in water and at several temperatures. [source] Effect of the Starting Microstructure on the Thermal Properties of As-Sprayed and Thermally Exposed Plasma-Sprayed YSZ CoatingsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2009Yang Tan Thermal barrier coatings (TBCs) experience thermal gradients, excessive temperature, and high heat flux from hot gases in turbines during service. These extended thermal effects induce sintering and significant microstructure changes, which alter the resulting thermal conductivity of the TBCs. To study the effects of different starting microstructures on the sintering behavior, plasma-sprayed yttria-stabilized zirconia (YSZ) TBCs produced from different starting powders and process parameters were subjected to thermal aging at several temperatures and time intervals, after which their thermal conductivity was measured at room temperature. The thermal conductivity results were analyzed by introducing the Larson,Miller parameter, that describes the creep-like behavior of thermal conductivity increase with annealing temperature and time. One set of coatings was also annealed under the same conditions and the thermal conductivities were measured at elevated temperatures. The temperature-dependent thermal conductivity data were analyzed and used to predict the long-term thermal property behavior for a general YSZ coating design. [source] On the hyperbolic system of a mixture of Eulerian fluids: a comparison between single- and multi-temperature modelsMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 7 2007Tommaso Ruggeri Abstract The first rational model of homogeneous mixtures of fluids was proposed by Truesdell in the context of rational thermodynamics. Afterwards, two different theories were developed: one with a single-temperature (ST) field of the mixture and the other one with several temperatures. The two systems are from the mathematical point of view completely different and the relationship between their solutions was not clarified. In this paper, the hyperbolic multi-temperature (MT) system of a mixture of Eulerian fluids will be explained and it will be shown that the corresponding single-temperature differential system is a principal subsystem of the MT one. As a consequence, the subcharacteristic conditions for characteristic speeds hold and this gives an upper-bound esteem for pulse speeds in an ST model. Global behaviour of smooth solutions for large time for both systems will also be discussed through the application of the Shizuta,Kawashima condition. Finally, as an application, the particular case of a binary mixture is considered. Copyright © 2006 John Wiley & Sons, Ltd. [source] Interdiffusion in SiGe alloys with Ge contents of 25% and 50% studied by X-ray reflectivityPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 10 2008M. Medun Abstract The interdiffusion in SiGe alloys has been studied by X-ray specular reflectivity using ex-situ and in-situ annealing experiments. We report on the evolution of the Ge profile of strain-compensated Si/SiGe multilayers due to high temperature annealing. These multilayers were grown pseudomorphically and strain-symmetrized on relaxed Si0.75Ge0.25 and Si0.5Ge0.5 pseudosubstrates by molecular beam epitaxy at 330 °C. The multilayer structures were annealed at several temperatures around 590 °C and around 800 °C. From modelling the X-ray specular reflectivity scans at various stages of the interdiffused structures, we obtained interdiffusion coefficients resulting in the activation energy and the prefactor for interdiffusion corresponding to Si0.75Ge0.25 and Si0.5Ge0.5. The results obtained ex-situ for Si0.5Ge0.5 and in-situ for Si0.75Ge0.25 provide accurate values of diffusion parameters. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Analysis of traps in CVD diamond films through thermal depumping of nuclear detectorsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 11 2004A. Balducci Abstract Carrier free paths in Chemical Vapour Deposition (CVD) diamond films depend on the presence of traps, which therefore strongly affect the performance of those CVD diamond based devices which rely on the electronic properties of the material, like radiation detectors. For the same reason, these devices can in turn be used as tools to study carrier dynamics. It is well known that some traps may be saturated by pre-irradiation with ionizing radiation (e.g. ,-particles), a process called "pumping" or "priming". Not all traps behave in the same way. Due to the large bandgap of diamond, both shallow (not affected by pumping) and deep traps for electrons and holes may exist. We measured, using 5.5 MeV 241Am ,-particles, the response of high quality CVD diamond based detectors after successive annealing steps performed at selected temperatures. The analisys of the decay of the detector efficency with annealing time at several temperatures allows a quantitative evaluation of the activation energy of these defects. Two main trapping centres connected to the pumping process were found, both related to holes, having activation energies of about 1.6 eV and 1.3 eV respectively. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Magnetotransport and magnetic properties of p -Zn1, xMnxTe:N , Carrier-induced ferromagnetismPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 3 2004K.-T. Nam Abstract The magnetic properties of nitrogen-doped p -Zn1, xMnxTe grown by MBE were studied through the magnetotransport measurements. In a sample of p -Zn1, xMnxTe with x = 0.034 and p = 4.7 × 1019 cm,3, a hysteresis loop was observed below 2.5 K in the Hall resistance and the magnetoresistivity, which indicates the ferromagnetic transition. From the plot of (RHall/Rsheet)2 against B/(RHall/Rsheet) at several temperatures, which corresponds to the so-called Arrott plot, we can estimate the Curie temperature (Tc) of the sample as about 3 K, suggesting that this sample has the higher Tc than ever reported. We also demonstrated, by means of light irradiation, that the strength of ferromagnetic interactions can be controlled by changing the hole concentration. An increase of the ferromagnetic behaviours such as a small increase of the coercive field was observed under light irradiation. This result strongly supports that the ferromagnetic transition in Zn1, xMnxTe is the carrier-induced one. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Analyses of Thick Lithium Coatings Deposited by Sputter-Evaporation and Exposed to AirPLASMA PROCESSES AND POLYMERS, Issue S1 2009C. Rigaux Abstract Lithium coatings on various substrates have numerous applications: Boron neutron capture therapy, neutron activation analysis, super-conducting tokamak etc. Traditionally these coatings are produced by well-known techniques such as electrochemistry and evaporation. In this work, we investigated a new method based on sputter-evaporation, which enables thick coatings (>10,µm) to be built on various substrates within a short timeframe. In order to minimize the process time, evaporation techniques can be used but the coating quality suffers. Moreover, it is well known that the use of DC magnetron sputtering results in the deposition of good quality coatings (smoothness, density, adhesion); however, the deposition rate is low. The rationale of this work is to combine these two techniques, yielding a sputter-evaporation process that possesses the advantages of each separate technique. Li is placed in a stainless steel crucible (cathode), and heated by the plasma generated by a magnetron discharge. The Li temperature is measured by a thermocouple welded onto the cathode and measured at different plasma power densities. The deposition rate of lithium is measured using a quartz balance and by profilometry, at several temperatures (from 0 to 580,°C). Li samples were depth-profiled with the resonant nuclear reaction 7Li(p,,)7. In addition to the concentration, certain characteristics like the density and the chemical reactivity of layers, are also important. Thus we have studied the evolution of the density with time, estimated by weight and profilometry measurements, and the change in morphology, by cross-sectional scanning electron microscopy (SEM), of samples exposed to air at room temperature. The evolution of the film compounds have also been determined by X-ray powder diffraction. These physical properties have been investigated for various bias substrates during deposition. [source] Modeling of three-dimensional flow and heat transfer in polystyrene foam extrusion diesPOLYMER ENGINEERING & SCIENCE, Issue 6 2008Manoj K. Choudhary A three-dimensional mathematical model was developed to investigate the nonisothermal, non-Newtonian polymer flow through the dies used in the polystyrene foam extrusion process. The model, based on the computational fluid dynamics (CFD) code, Polyflow, allowed for the shear rate and temperature dependence of the shear viscosity of the blowing agent laden polystyrene melt. The model also accounted for viscous heating. The shear viscosity of the polystyrene-blowing agent mixture was measured experimentally at several temperatures. The model was used to calculate pressure, flow, and temperature distributions in two different dies used for industrial-scale extrusion of polystyrene foams. The article presents a selection of computed results to illustrate the effect of die design on uniformity of flow at the die exit, the overall pressure drop in the die, relative magnitudes of pressure drop in the land section versus the rest of the die, and temperature distribution in the die. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers. [source] Oxygen permeability of biaxially oriented polypropylene filmsPOLYMER ENGINEERING & SCIENCE, Issue 4 2008Y.J. Lin The effect of thermal history on the oxygen permeability of biaxially oriented polypropylene (BOPP) films was investigated. Compression-molded sheets prepared with different cooling rates were biaxially oriented at several temperatures in the range between the onset of melting and the peak melting temperature and at a strain rate similar to that encountered in a commercial film process. The stress response during stretching was found to depend on the residual crystallinity in the same way regardless of the thermal history of the compression-molded sheet. Biaxial orientation reduced the oxygen permeability measured at 23°C; however, the reduction did not correlate with the amount of orientation as measured by birefringence or with the fraction of amorphous phase as determined by density. Rather, the decrease in permeability was attributed to reduced mobility of amorphous tie molecules. A single one-to-one correlation between the oxygen permeability and the intensity of the dynamic mechanical ,-relaxation was demonstrated for all the films used in the study. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers [source] Dielectric monitoring of curing of liquid oligomer-modified epoxy matricesPOLYMER INTERNATIONAL, Issue 9 2001G Kortaberria Abstract Dielectric measurements were performed in ,real-time' at several temperatures to follow polymerization reactions on blends of a diglycidyl ether of bisphenol A (DGEBA) epoxy resin with 4, 4,-diaminodiphenylmethane (DDM) hardener and different amounts of polyoxypropylenetriamine (POPTA) oligomer. These systems exhibit phase separation induced by molar mass increasing through curing of the resin. Monitoring of phase separation and vitrification (related to the ,-relaxation) was performed by this technique. The results are compared with those for the unmodified resin,hardener mixture. The change of the main ,-relaxation with cure time, cure temperature, and amount of modifier was measured for the mixtures. This change of the main relaxation through curing in the frequency domain was indicative of the cure reaction advancement, because of its dependence on the viscosity of the medium. The change of the ionic conductivity during curing was also analysed, showing its dependence upon cure temperature. © 2001 Society of Chemical Industry [source] Variable-temperature studies of the 4-isopropylphenol crystal structure from X-ray diffraction.ACTA CRYSTALLOGRAPHICA SECTION B, Issue 4 2002Comparison of thermal expansion, molecular dynamics with spectroscopic results Crystalline 4-isopropylphenol, C9H12O, an optically non-linear material, was studied by X-ray diffraction in order to determine its structure at several temperatures in the 95,300,K range. The thermal expansion coefficients have been calculated from the lattice parameters' dependence on temperature. The rigid-body analysis of the anisotropic displacement parameters including the correlation with the internal motion of large amplitude provided the values of the molecular translation and libration tensors at the temperatures studied and was used to characterize the torsional motion of the isopropyl group. The calculated normal modes and internal torsion frequency were compared with the wave numbers at the maximum of bands in the low-frequency Raman scattering, FTIR and inelastic neutron scattering spectra. [source] Complex 1H,13C-NMR relaxation and computer simulation study of side-chain dynamics in solid polylysineBIOPOLYMERS, Issue 3 2005Alexey Krushelnitsky Abstract The side-chain dynamics of solid polylysine at various hydration levels was studied by means of proton spin,lattice relaxation times measurements in the laboratory and tilted (off-resonance) rotating frames at several temperatures as well as Monte Carlo computer simulations. These data were analyzed together with recently measured carbon relaxation data (A. Krushelnitsky, D. Faizullin, and D. Reichert, Biopolymers, 2004, Vol. 73, pp. 1,15). The analysis of the whole set of data performed within the frame of the model-free approach led us to a conclusion about three types of the side-chain motion. The first motion consists of low amplitude rotations of dihedral angles of polylysine side chains on the nanosecond timescale. The second motion is cis,trans conformational transitions of the side chains with correlation times in the microsecond range for dry polylysine. The third motion is a diffusion of dilating defects described in (W. Nusser, R. Kimmich, and F. Winter, Journal of Physical Chemistry, 1988, Vol. 92, pp. 6808,6814). This diffusion causes almost no reorientation of chemical bonds but leads to a sliding motion of side chains with respect to each other in the nanosecond timescale. This work evidently demonstrates the advantages of the simultaneous quantitative analysis of data obtained from different experiments within the frame of the same mathematical formalism, providing for the detailed description of the nature and geometry of the internal molecular dynamics. © 2005 Wiley Periodicals, Inc. Biopolymers 78: 129,139, 2005 This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] | |||||||||||||||||||