DATABASE OF PHYSICAL PROPERTIES OF FOODS: SUBGROUP OF MECHANICAL AND RHEOLOGICAL PROPERTIES

2001 ◽  
Vol 32 (2) ◽  
pp. 155-160 ◽  
Author(s):  
M. HOUŠKA ◽  
P. NESVADBA ◽  
Z. MAYER

This article examines the change in stress and strain media, in particular natural leonardite (brown coal), prepared for grinding and during grinding, due to the restructuring of the material, i.e. changes in the relative position and deformation of the elements of the structure, including at the level of macromolecules that are inert to the deformation and relaxation processes, provide important for the technology to use improved rheological properties of the soil structure based on dispersion of leonardite, information about the physical properties of the material and its structure. The time variation of the stress in an inert-viscous-elastic medium with a constant strain rate depending on the values of the rheological parameters, it is possible to occur by three laws: aperiodic (steady), critical and oscillatory damp


2017 ◽  
Vol 67 (4) ◽  
pp. 569-578
Author(s):  
Beata Szulc-Musioł ◽  
Barbara Dolińska ◽  
Justyna Kołodziejska ◽  
Florian Ryszka

Abstract Effects of two independent variables - the content of quercetin (0 or 1 or 1.5 or 5 %) and the content of plasma (0 or 2 or 4 or 6 %) - on the organoleptic properties and rheological parameters of model formulations prepared on an amphiphilic base were estimated. The consistency of all ointments was uniform, and the content of quercetin and plasma lay within the predefined range. Tested ointments are non-Newtonian systems. The content of quercetin and plasma was found to have a significant effect on the rheological properties of the ointments. An increase in the content of plasma in ointments was accompanied by a significant increase in their hardness, viscosity and shear stress and a reduction of their spreadability. The best rheological properties were shown by formulation F-3, containing 1.5 % of quercetin and 2 % of plasma.


2018 ◽  
Vol 913 ◽  
pp. 1062-1069
Author(s):  
Min Wu ◽  
Lian Li ◽  
Bian Yang He ◽  
Jian Ying Yu

The crystal structure, microscopic morphology, particle size distribution and UV shielding properties of layered double hydroxides (LDHs) with different particle size were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser particle size analysis and ultraviolet and visible (UV-vis) spectrophotometer. The effects of LDHs with different particle size on the physical, rheological properties and UV aging resistance of bitumen were investigated by conventional physical properties and dynamic rheological characteristics. The results indicated that the particle size of LDHs had a little effect on the physical properties, and it had some influence on rheological properties of bitumen, but its influence on the UV aging resistance of bitumen was different significantly. When UV aging time was 9d, the viscosity aging indexes of bitumen modified by LDHs with different particle size (80nm, 115nm and 180nm) decreased by 48.2%, 58.1% and 63.8% compared with the pristine bitumen, respectively. LDHs with the particle size of 180 nm showed better improvement than other two kinds of LDHs on UV aging resistance of bitumen.


2012 ◽  
Vol 430-432 ◽  
pp. 24-27
Author(s):  
Lei Xiong ◽  
Qi Lang Lin

A bismaleimide (BMI) resin system based on allyl condensed polynuclear aromatic resin and 4,4'-bismaleimidodiphenyl methane was prepared in this paper. The chemical structures and rheological properties of the resin prepolymer were characterized by FTIR and viscometer, respectively. DSC was used to study the curing reaction of the resin prepolymer, and TG-DTG was employed to study the thermal behaviors of the cured resin. Moreover, physical properties of the BMI resin, including mechanical and dielectric properties, were studied. The results showed that the BMI resin had good thermo-stability, good mechanical properties and excellent dielectric properties. Introduction


2007 ◽  
Vol 40 (2) ◽  
pp. 690
Author(s):  
G. E. Christidis

The new method of Christidis and E beri (2003), which determines the layer charge and charge distribution of dioctahedral smectites in bentonites is presented and is compared to the existing methods for determination of layer charge and charge distribution, namely the structural formula method and the alkylammonium method. The new method is based on the comparison ofXRD traces of K-saturated, ethyleneglycol solvated smectites with simulated XRD-traces calculated for three-component interlayering. Applications of the method include modeling of the evolution of smectite layers towards illite during diagenesis, and study of the influence of layer charge and charge distribution of smectites on important physical properties of bentonites such as rheological properties (viscosity, gel strength, yield point and thixotropy) and swelling. Smectites with layer charge between -0.425 and-0.47 to - 0.48 equivalents phfu affect rheological properties in a different way compared to smectites with higher or lower layer charge than this layer charge interval. Based on these observations a new classification scheme for smectites has been proposed according to their layer charge. In this classification scheme the term smectites with intermediate layer charge has been introduced.


PETRO ◽  
2018 ◽  
Vol 5 (2) ◽  
Author(s):  
Widia Yanti ◽  
Abdul Hamid ◽  
Ibnu Badar Bajri

<p>The unidealized of physical and rheological mud can occured when drilling on rock layers with high salt concentrations. It is therefore necessary to add an additive to balance the effect of the salt. The aims of this study is to see the effect of salt addition on various temperature drilling mud.</p><p>This research will use two types of mud with different oil-water ratio. The drilling mud will be divided into four compositions, ie LA, LB, LC, and LD. LA and LC compositions have an oil-water ratio of 80% oil and 20% fresh water. While LB and LD compositions have oil-water ratio of 75% oil and 25% fresh water. Then the study was conducted at various temperatures, ie 80 °F, 130 °F, 180 °F, 230 °F, 280 °F, and 330 °F. After observing of the physical properties and rheology of drilling mud, it was found that the effect of adding salt NaCl can improve the physical and rheological properties of mud such as density, viscosity, gel strengh, mud cake, and solid content. Conversely, the effect of adding NaCl salt may reduce the nature of electrical stability. While the increasing of the temperature can reduce the physical and rheological properties of mud and on the contrary the loss of water and mud cake will increase.</p>


Author(s):  
Mai Rajwan Al-kateb, Ramadan Attra, Ahmad Mofeed Hasn Sobh Mai Rajwan Al-kateb, Ramadan Attra, Ahmad Mofeed Hasn Sobh

The research aims to study the optimum conditions for germination of Syrian hard wheat Cham 3, and to study the possibility of benefiting from sprouted wheat in fortifying Syrian Arab bread. The results were then treated statistically at the 95% reliability level using the Minitab program version 14. 0. It was evident through the statistical results that the optimum germination conditions for Syrian durum wheat Sham 3 is a temperature of 20 °C for a period of 4 days, as with these conditions the folic acid content reached 1. 75 mg / kg, which is approximately 13 times the folic acid content of meal wheat without sprouting (0. 135 mg / kg). By studying the rheological properties of flour and meal using Alveograph and Mixolab, it was noticed that germination led to a decrease in the strength of meal wheat. Where all the Alveograph indicators (P, L, G, W) and Mixolabs (C1, C2, C3, C4, C5, DDT) of germinated wheat significantly decreased compared to both flour and non-germinated meal. It was found that the possibility of benefiting from the Syrian sprouted wheat in fortifying the Syrian Arab bread, and the best percentage of adding crushed wheat sprouts to the Arabic bread is 40%, as it gave a sensory acceptable Arabic bread in terms of texture, separability, foldability and in terms of physical properties. The benefiting from the Syrian sprouted wheat in fortifying the Syrian Arab bread is possible, and the best percentage of adding sprouted wheat meal to the Arabic bread is 40%, as it gives a sensory acceptable Arabic bread in terms of texture, separability, foldability and in terms of physical properties.


1998 ◽  
Vol 274 (2) ◽  
pp. L258-L263 ◽  
Author(s):  
Laura Trout ◽  
Malcolm King ◽  
Wei Feng ◽  
Sarah K. Inglis ◽  
Stephen T. Ballard

The combination of both Cl− and[Formula: see text] secretion inhibitors causes an accumulation of mucins within the submucosal gland ducts of acetylcholine (ACh)-treated bronchi [S. K. Inglis, M. R. Corboz, A. E. Taylor, and S. T. Ballard. Am. J. Physiol. 272 ( Lung Cell. Mol. Physiol. 16): L372–L377, 1997], suggesting indirectly that these agents block airway gland liquid secretion. The present study tested the hypotheses that ACh-stimulated liquid secretion is driven by Cl−and [Formula: see text] secretion and that inhibition of this process leads to secretion of a dehydrated mucus with altered rheological properties. Excised distal bronchi from pigs were pretreated with either a combination of Cl− and[Formula: see text] secretion inhibitors (bumetanide, acetazolamide, dimethylamiloride, and 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid) or the dimethyl sulfoxide vehicle and were then treated with ACh to induce secretion. The rate of mucus liquid secretion was substantially reduced when the airways were pretreated with the anion secretion inhibitors. Mucus liquid from inhibitor-pretreated airways contained almost threefold more nonvolatile solids than the control liquid. Rheological analysis revealed that mucus liquid from inhibitor-pretreated airways expressed a significantly greater log G * (rigidity factor), whereas tangent δ (recoil factor) was significantly reduced. These results suggest that 1) ACh-induced liquid secretion in bronchi is driven by both Cl− and[Formula: see text] secretion and 2) inhibition of ACh-induced liquid secretion results in the secretion of mucus with a reduced water content and altered rheological properties.


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