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Abstract  

Isothermal titration calorimetry (ITC) and reaction calorimetry (RC) have been used to construct the solid-liquid equilibrium line in ternary systems containing the solute to precipitate and an aqueous mixed solvent, and to study polymerization reactions under real process conditions, respectively. Phase diagrams have been established over the whole concentration range for some benzene substituted derivatives, including o-anisaldehyde, 1,3,5-trimethoxybenzene and vanillin, in {water + alcohol}mixtures at different temperatures. Acrylamide polymerization in aqueous solution using potassium permanganate/acid oxalic redox system as initiator was investigated on a homemade calorimeter, which works according to the isoperibolic mode. A Calvet type differential RC was used to illustrate the applicability of temperature oscillation calorimetry (TOC) for the evaluation of the heat transfer coefficient during the course of reaction.

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Abstract  

This article presents a model, based on dimensionless groups, to predict the viscosity of nanoparticle suspensions, nanofluids. This empirical model expresses the viscosity of a nanofluid as a function of the following: viscosity of the base liquid, particle volume fraction, particle size, properties of the surfactant layer, and temperature. According to this model, viscosity changes nonlinearly with nanoparticle loading. Compared to other models, the new model is in good agreement with experimentally determined viscosity data for alumina–water nanofluids.

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Acta Alimentaria
Authors: A. Harasztos, G. Balázs, P.N. Csőke, S. D’Amico, R. Schönlechner, and S. Tömösközi

The positive nutritional impact of dietary fibres (DF) gives growing interest to their role in the formation of wheat product quality. Although we are getting closer to characterize the effect of DF on the end use quality, the roles of individual components are not well described yet. Arabinoxylans (AX) are the main compounds of wheat DF, therefore getting more knowledge about its behaviour in wheat based food systems, like dough or end products, could be useful from both theoretical and practical points of view. The aim of this study was to investigate the impact of the AX content on wheat flour quality using a dough model system provided by blends of flour and AX isolate. Rapid Visco Analyser (RVA) and recently developed micro Zeleny test were used for characterization of mixtures.

We found that although Zeleny values are basically related to protein-dependent quality, the addition of AX isolate has major impact on the sedimentation volume of flour. In the RVA studies we demonstrated that AX has influence not only on the viscosity values but also on the rate of viscosity change. The effect of AX addition was compared to that of starch addition and was corrected by the rate of dilution. The model system and the experimental method applied here can be suitable to separate the individual effects of non-starchy carbohydrates.

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Journal of Thermal Analysis and Calorimetry
Authors: D. Lőrinczy, Zsuzsanna Vértes, Franciska Könczöl, and J. Belágyi

Abstract  

Actin is one of the main components in the eukaryote cells which plays significant role in many cellular processes, like force-generation, maintenance of the shape of cells, cell-division cycle and transport processes. In this study the thermal transitions of monomer and polymerized actins were studied to get information about the changes induced by polymerization and binding of myosin to actin using DSC and EPR techniques. The main thermal transition of F-actin was at 67.5°C by EPR using spin-labeled actin (the relative viscosity change was around 62°C), while the DSC denaturation T ms were at 60.3d°C for G-actin and at 70.5°C for F-actin. Applying the Lumry-Eyring model to obtain the parameters of the kinetic process and calculate the activation energy, a ‘break’ was found for F-actin in the function of first-order kinetic constant vs. 1/T. This indicates that an altered interdomain interaction is present in F-actin. The addition of myosin or heavy meromyosin (HMM) in different molar ratio of myosin to actin has changed significantly the EPR spectrum of spin-labeled F-actin, indicating the presence of the supramolecular complex. Analyzing the DSC traces of the actomyosin complex it was possible to identify the different structural domains of myosin and actin.

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Journal of Thermal Analysis and Calorimetry
Authors: R. A. Candeia, F. S. M. Sinfrônio, T. C. Bicudo, N. Queiroz, A. K. D. Barros Filho, L. E. B. Soledade, I. M. G. Santos, A. L. Souza, and A. G. Souza

viscosity change, the breakage of the ester chains, release of volatile products, and oxidation of ester chains and polymerization of non-volatile materials [ 31 , 32 ]. In this study, oxidation and polymerization were more pronounced than the other two

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like stevia have synergistic effects on viscosity ( Konar et al., 2018 ). Fig. 4. The viscosity changes of mango nectar samples in the 1st and 45th days of storage. Data are presented as mean ± standard deviation ( n = 3). Different letters indicate

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. , No , H.K. , and Prinyawiwatkul , W. ( 2014 ). Viscosity changes of chitosan solution affect physico-functional properties and consumer perception of coated eggs during storage . LWT – Food Science and Technology , 55 ( 1 ): 67 – 73 , https

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International Review of Applied Sciences and Engineering
Authors: Adebayo Surajudeen Adekunle, Adekunle Akanni Adeleke, Peter Pelumi Ikubanni, Peter Olorunleke Omoniyi, Tajudeen Adelani Gbadamosi, and Jamiu Kolawole Odusote

kinematic viscosity of 43.95 mm 2 /s at 40 °C. This shows that the higher the free fatty acid, the lower the flash point. The kinematic viscosity change was observed to have direct relation to the degree of saturation/unsaturation of fatty acid in the oils

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