Theological Properties Research Articles

Numerical study of thermal performance of yield stress rheological liquid under suspension of hybrid nanostructures: The finite element approach

Enhancement of heat transfer employing nanofluids, studied numerically, observed profound effects in thermophysical and theological properties used in various applications such as avionics, laser diode, rocket nozzels and microelectronics. In this paper, the influence of thermal radiations and hybrid nanoparticles on free convection flow and heat transfer of Casson hybrid nanofluid over vertical plate is investigated. A mixture of pure water and ethylene glycol has been considered as a base Casson fluid while Copper oxide ([Formula: see text]) as nanofluid (single kind) and, Copper oxide ([Formula: see text]) and Silicon dioxide ([Formula: see text]) (double kind known as hybrid nanofluid) are disseminated in base Casson fluid mixture to be formed as hybrid nanofluid. The governing system of partial differential equations of the flow and heat transfer processes is converted to a system of well-posed coupled nonlinear ordinary differential equations by using the similarity transformations. The resulting system is solved using the Galerkin finite element (GFE) technique. The quadratic Lagrange polynomials are used as basis functions over the mesh of about 1000 to 2000 finite elements and the nonlinear system of order 6003 and upto 12003 is solved. The accuracy of developed numerical methods is confirmed by comparing their results with convection flow and heat transfer with nanoparticles. Thereafter, the said solutions are used to investigate the effects of thermal radiation, hybrid nanoparticle volume friction, Prandtl number, type of flow and heat transfer behavior. The innovative results of the present study reported higher velocities in suspensions with low sphericity particles and the radiation parameter is directly proportional to the temperature with the use of nano and hybrid nanoparticles. It has also been noted that the GFE method is a more stable numerical technique as compared with other existing analytic and semi-analytical methods.

Effects of composition, thermal, and theological properties of rice raw material on rice noodle quality.

The study aims to evaluate the relationships between characteristics of regional rice raw material and resulting quality of rice noodles. Four of most commonly used rice cultivars in Guangxi for noodles production were investigated. The results showed that compositions of rice flour primarily affected gelatinization and retrogradation, which then influenced the textural and sensory properties of rice noodles. Amylose content had strong positive correlation with peak viscosity (PV) and trough viscosity (TV) of rice flour (P < 0.01). PV and TV had strong negative correlations with adhesive strength (P < 0.01) and positive correlations with chewiness (P < 0.05), hardness, peak load and deformation at peak of rice noodles (P < 0.01). Protein content had positive correlation with the Setback of rice flour (P < 0.05), which is known to have influences on retrogradation. In addition, solubility had positive correlations with cooking loss (P < 0.01) and broken rate (P < 0.05) of rice noodles and strong negative correlation with its springiness (P < 0.01). Swelling power had negative correlation with broken rate (P < 0.05). As sensory score of rice noodles was negatively correlated with broken rate (P < 0.05) and cooking loss (P < 0.01) and positively correlated with springiness (P < 0.01), solubility and swelling power of rice flours were presumed to be useful for predicting consumer acceptability of rice noodles.

STUDYING THE EFFECT OF ADDING SWEET POTATO FLOUR ON THE CHEMICAL AND RHEDOGICAL PROPERTIES OF SOME PRODUCTS

This study was conducted in the laboratories of the College of Agriculture, Tikrit University / Department of Food Science, and at the Tikrit Mill. In this study, spelled flour was replaced with sweet potato flour with replacement rates 5, 10 and 15%. And the results showed the following: A noticeable decrease in the moisture content of the compound flour samples compared to the standard control sample. It also showed a decrease in the protein content. This decrease was most intense when the replacement ratios increased, in the highest level of decrease was recorded at the replacement rate of 15%. The results also showed a significant increase in the content of ash and fats compared to the standard sample of the control, while the concentration of 15% recorded the highest value of absorbance in the theological properties when measuring with a farinograph device. The same is the case for amylograph, Whereas, the higher the replacement rates, the higher the degree of gelatinization and the degree of viscosity, and it is clear from this study that 15% is the best percentage in terms of the theological properties of the product.

Overcoming Reconciliation as a Wicked Problem

Abstract This contribution provides clues as to why (the quest for) reconciliation in South Africa fits the broad definition of a wicked problem. Popularized by Horst Rittel and Melvin Webber (1973), wicked problem refers to something that is either too difficult or nearly impossible to resolve. It is abundantly clear from the available literature that reconciliation is understood in very different ways. Not only is there a lack of conceptual clarity, but strategies aimed at working towards this ideal reveal or produce new problems as an unintended consequence. Some strategies approach the discourse for the purpose of political expediency, while others are more interested in its theological (or existential) properties. This tension is referenced as the dominant split between heaven and earth. Notwithstanding the complexity of the problem, this contribution alludes to the limitations of such approaches if those who propagate them insist that such views remain mutually exclusive. Building on the theology of Allan Aubrey Boesak and Curtiss Paul DeYoung (2012), this contribution is an attempt to avoid the polarization of such views and highlight the fundamental asymmetry between divine and human action. This is underscored by the work of Christ through which God reconciled the world to himself (2 Cor. 5:19) and the ministry of reconciliation in society. In taking this approach, one avoids the tendency to provide superficial answers to a complex (wicked) problem.

Time and Temperature Dependence of the Structural Evolution for Polyamide 1012

The Theological property evolution of polyamide 1012 (PA1012) in the isothermal process in molten state has been investigated. The results show that the viscosity increases and crosslinking reaction occurs simultaneously together with the increase of temperature, thus causing the variation of storage modulus (G′) and loss modulus (G″) in the repeated frequency sweeps with residual time. This research has pointed out that the superposition is valid for monitoring the complex behavior composed of the viscosity increasing and crosslink occurring process by tracing the variation behavior of the crossover points of G’ and G” with time, revealing the same time-temperature dependence of the two reactions in the isothermal process. A normalized master curve has been proposed to describe the melt behavior at a given temperature.

Application of Natural Polymer Drilling Fluid System in J7 Well Area

The natural polymer drilling fluid mainly includes four kinds of additives: natural polymer inhibitive coating agent IND30, filtrate reducer NAT20, non-fluorescence “white asphalt” NFA-25 and polyol PGCS-1. This system has been successfully applied in many wells of the J7 well area by Xinjiang oilfield Company. The in-situ application show that the drilling fluid system possesses excellent features: particular theological property, strong inhibition, strong anti-collapse ability, oil/gas reservoir protection and environment protection.

Properties of Aqeous Solutions of O,N-Carboxymethyl Chitosan with Various Additives

Samples of carboxymethyl chitosan have been synthesized with different extents of substitution by changing the reaction conditions. Carboxymethyl chitosan completely dissolves in water when the extent of substitution exceeds 90%. The theological properties were studied for 4% aqueous solutions of carboxymethyl chitosan with CaCl2 and Ca(OH)2 as additives as well as for a mixture of carboxymethyl chitosan and polyethylene oxide with added CaCl2. The introduction of additives to aqueous solutions of carboxymethyl chitosan leads to enhanced viscosity and gel formation.

The influence of fat substitution with κ-carrageenan, konjac, and tragacanth on the textural properties of low-fat sausage.

Reducing the fat content of meat products and producing healthier products is considered as an important matter in politics in prevention of many hazardous diseases and providing consumers' health. The aim of this study was reducing the fat in fatty sausages based on oil reduction and using fat substitutes, including κ‐carrageenan, konjac, and tragacanth, and comparing them according to their texture characteristics. κ‐carrageenan, konjac, and tragacanth gums were used at four different levels (0.0, 0.5, 1.0, and 1.5) as the fat substitutes in producing low‐fat sausage with 70% reduction based on formulated oil. Texture profile analysis (Hardness, Gumminess, Springiness, and Chewiness) was performed in this study for analyzing the texture characteristics, in 1‐, 10‐, 20‐, and 30‐day time intervals after production. The results showed that producing low‐fat sausage was possible using all the three gums, among the low‐fat samples of which, the texture samples containing konjac were more favorable. Textural properties indicated that fat reduction increased in firmness and gum addition can partially compensate deficits in rheological properties, although during the storage, low‐fat sausages without any gum have highest decline in Hardness. Konjac gum illustrated the best theological properties between treatments.

Synthesis and Linear Viscoelasticity of Polystyrene Stars with a Polyketone Core

We report on a novel synthetic route to synthesize relatively large quantities of polystyrene (PS) star polymers with targeted arm functionality and molar mass and their theological properties in the molten state. The synthetic route involves grafting styrene monomers onto a modified (aliphatic, alternating) polyketone backbone with a specific number of initiating grafting sites using controlled atom transfer radical polymerization (ATRP). Several polyketone precursors were used. This resulted in a large array of star polystyrenes with nonspherical cores and varying average arm length and number of arms. Their linear viscoelasticity was investigated and discussed in the context of the known response of anionically synthesized stars. Using a powerful characterization toolbox, including state-of-the-art interaction chromatography, rheometry, and tube modeling via the branch-on-branch (BoB) algorithm, we have assessed the viscoelasticity of these star polymers quantitatively. In particular, we have demonstrated a variability in molecular structure, which differs substantially from their anionically synthesized counterparts. Hence, whereas this new family of star polymers is not recommended for fundamental studies of polymer physics such as the molecular origin of relaxation mechanisms without prior extensive fractionation, they could be used in studies of mixtures as well as industrially relevant processing operations that require large amounts of polymeric stars.

Attributes of God: Conceptual Foundations of a Foundational Belief.

Anthropomorphism, or the attribution of human properties to nonhuman entities, is often posited as an explanation for the origin and nature of God concepts, but it remains unclear which human properties we tend to attribute to God and under what conditions. In three studies, participants decided whether two types of human properties-psychological (mind-dependent) properties and physiological (body-dependent) properties-could or could not be attributed to God. In Study 1 (n=1,525), participants made significantly more psychological attributions than physiological attributions, and the frequency of those attributions was correlated both with participants' religiosity and with their attribution of abstract, theological properties. In Study 2 (n=99) and Study 3 (n=138), participants not only showed the same preference for psychological properties but were also significantly faster, more consistent, and more confident when attributing psychological properties to God than when attributing physiological properties. And when denying properties to God, they showed the reverse pattern-that is, they were slower, less consistent, and less confident when denying psychological properties than when denying physiological properties. These patterns were observed both in a predominantly Christian population (Study 2) and a predominantly Hindu population (Study 3). Overall, we argue that God is conceptualized not as a person in general but as an agent in particular, attributed a mind by default but attributed a body only upon further consideration.

Effect of canopy structures on CO2 capture capacity and properties of NONMs

Novel nanoparticle organic hybrid materials (NOHMs), which have the potential for carbon dioxide physical-chemical capture capacity, have been synthesized. Multi-walled nanotubes (MWNTs), which have the physical storage capacity for gas, were assembled as the core of NOHMs. The surface of MWNTs was functionalized with Jeffamine M-2070 and M-1000 (polyetheramines), which can absorb carbon dioxide via chemical reaction. The structure of NOHMs was verified by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and UV-Vis spectroscopy. The weight percentages of MWNTs in NOHMs are 22.1 wt% and 21.4 wt%, respectively. Differential scanning calorimetry (DSC) curves show that the relative crystallinity percent of NOHMs-M2070 and NOHMs-M1000 is 38.88 and 40.56 %, respectively. Transmission electron microscopy (TEM) images show the morphology and structure of NOHMs at the nanometer level. Theological properties of NOHMs exhibit the viscosity and elasticity of NOHMs generated from liquid-like behavior varying the temperature and stress. CO2 capture capacity is tested from 0 to 6 MPa at 298 K. The amine groups, ether groups, and physical interaction between MWNTs and JEFFAMINE have significant effect on CO2 capture capacity. The storage property of MWNTs contributes to CO2 capture capacity. NOHMs based on MWNTs with excellent regeneration capacity have the promising potential for CO2 capture.

The Influence of Non-Solvent Addition on the Independent and Dependent Parameters in Roller Electrospinning of Polyurethane

This paper discusses the effects of 1,1,2,2 tetrachlorethylen (TCE) non-solvent addition on the independent (electrical conductivity, dielectric constant, surface tension and the theological properties of the solution etc.) and dependent parameters (number of Taylor cones per square meter (NTC/m2), spinning performance for one Taylor cone (SP/TC), total spinning performance (SP), fiber properties such as diameter, diameter uniformity, non-fibrous area) in roller electrospinning of polyurethane (PU). The same process parameters (voltage, distance of the electrodes, humidity, etc.) were applied for all solutions during the spinning process. According to the results, the effect of TCE non-solvent concentration on the dielectric constant, surface tension, rheological properties of the solution and also spinning performance was important statistically. Beside these results, TCE non-solvent concentration effects quality of fiber and nano web structure. Generally high fiber density, low non-fibrous percentage and uniform nanofibers were obtained from fiber morphology analyses.

Robust Organogels from Nitrogen-Containing Derivatives of (R)-12-Hydroxystearic Acid as Gelators: Comparisons with Gels from Stearic Acid Derivatives†

Thirteen members of a new class of low molecular-mass organogelators (LMOGs), amides, and amines based on (R)-12-hydroxystearic acid (HSA; i.e., (R)-12-hydroxyoctadecanoic acid) and the properties of their gels have been investigated by a variety of structural and thermal techniques. The abilities of these LMOGs, molecules with primary and secondary amide and amine groups and the ammonium carbamate salt of 1-aminooctadecan-12-ol, to gelate a wide range of organic liquids have been ascertained. Their gelating efficiencies are compared with those of HSA and the corresponding nitrogen-containing molecules derived from stearic acid (i.e., HSA that lacks a 12-hydroxyl group). Several of the HSA-derived molecules are exceedingly efficient LMOGs, with much less than 1 wt % being necessary to gelate several organic liquids at room temperature. Generally, the self-assembled fibrillar networks of the gels consist of spherulitic objects whose dimensions depend on the protocol employed to cool the precursor sol phases. X-ray studies indicate that the LMOG molecules are packed in lamellae within the fibers that constitute the spherulites. In addition, some of the organogels exhibit unusual thixotropic properties: they recover a large part of their viscoelasticity within seconds of being destroyed by excessive strain shearing. This recovery is at least an order of magnitude faster than for any other organogel with a crystalline fibrillar network reported to date. Correlations of these LMOG structures (as well as with those that lack a hydroxyl group along the n-alkyl chain, a headgroup at its end, or both) with the properties of their gels, coupled with the unusual theological properties of these systems, point to new directions for designing LMOGs and organogels.

DYNAMIC BEHAVIOUR OF SHEAR-TYPE MAGNETORHEOLOGIC GREASE DAMPER ROTOR SYSTEM

In order to greatly reduce the effect of sedimentation in magnetorheological fluids (MRF) on dynamic behavior of the MRF based devices, a kind of magnetorheological greases (MRG), whose Theological property can also be significantly changed on the application of an external magnetic field, is presented, and a MRG based shear-type damper operating in shear mode for rotor system of rotational machinery and a flexible rotor system with an over-hung disk are developed. The controllability of the shear-type MRG damper on the dynamic behavior of a rotor system, the effectiveness of the shear-type MRG damper for attenuating the rotor's vibration, the suitability of the MRG damper for active vibration control of rotor systems, and the repeatability of the dynamic characteristics of the shear-type MRG damper rotor system during a longer period of time are experimentally studied in the flexible rotor system. Results show that the dynamic behavior of the shear-type MRG damper rotor system can be controlled on the application of an external magnetic field produced by a low voltage electromagnetic coil, the shear-type MRG damper can greatly suppress the vibration of the rotor system at a properly magnetic field, the dynamic behavior of the shear-type MRG damper rotor system does not change during a longer period of time, and the shear-type MRG damper is suitable for an actuator to actively control the vibration of rotor systems.

Improving The Quality And Nutritional Status Of Maize Fermented Meal By Fortification With Bambara Nut

Studies were conducted to develop an appropriate household/small scale enterprise level technique for the production of bambara groundnut-fortified fermented maize dough or meal by comparing different treatments, processing methods and fortification levels. The effect of fortification of maize based traditional foods with legume protein, bambara nut at 0%. 10% and 20% replacement levels, on the rate of fermentation and product quality were investigated. Sensory characteristics, amino acid pattern, proximate composition (moisture, protein, fat, ash) pH, titratable acidity and theological properties (pasting temperature, peak viscosity, viscosity at 95°C and 95°C hold and viscosity at 50°C) were used as the indices of quality. The results obtained showed that Bambara nut addition caused only minimal changes in the proximate composition with the exception of protein content which increased remarkably from 10.1% to 16.4% and 10.1% to 16.2% with 20% bambara nut addition respectively for boiled bambara nut fortified fermented maize dough and raw bambara nut fortified fermented maize dough. The product pH decreased with concomitant increase in moisture, fat, ash and titratable acidity with increasing bambara addition. A significant improvement was also achieved in the lysine and tryptophan pattern of the fortified dough compared to the unfortified. However, boiling bambara nut for 20mins before incorporation into the maize for milling and fermentation imparted a desirable flavour. This results showed that the most appropriate technique for the production of bambarafortified high protein fermented maize dough has been suggested to involve incorporation of boiled whole bambara nut in soaked maize before milling and fermentation for improved sensory characteristics, enhanced nutritive valve and optimal functional properties. Little or no changes in the pasting viscosity characteristic occurred in sample containing raw bambara nut. Organoleptic evaluation revealed that the foods were well accepted. Based on the findings of the study, the application of Bambara nut fortification to traditional foods suggests a viable option of promoting the nutritional quality of African maize-based traditional foods with acceptable rheological and cooking qualities.

フレッシュセメントペーストに対するせん断ひずみ依存型粘塑性モデルの適用性に関する研究

In this study, small sized shear box test of cement paste was carried out for the quantification of shear strain dependent visco-plastic model, in order to investigate the Theological properties of cement paste which is the most important fundamental material for mortar and concrete. And, Theological constants measured by the experiment were compared with the analytical results by visco-plastic finite element method (VFEM). As the results, it was confirmed that the Theological constants of cement paste are dependent on the shear strain, and this property is varied with the water-cement ratio and the dosage of high-range water-reducing AE agent and segregation control agent. Furthermore, according to the result of numerical analysis by VFEM, it was clarified that the degree of the shear strain variable in the shear stain dependent visco-plastic model should be determined as a linear model to have good agreement with measured values in high-fluidity material. However, in case of dry consistency, good agreement was attained with cubic model.

The Morphology and Corresponding Rheological Properties of Phase-Separating Polymer Blends Subject to a Simple Shear Flow

The chain-stretching effect on the morphology and the corresponding theological properties are analyzed theoretically. In order to confirm the theoretical analysis, the simulations based on the time-dependent Ginzburg-Landau (TDGL) equation with the free energy functional contains the information of chain conformation have been performed in q-space by means of the semi-implicit Fourier spectral method. This method is more effcient and accurate, and moreover, the periodic boundary condition used in r-space cell dynamics scheme (CDS) can be released. The simulation results agree with the theoretical analysis quite well and show that the chain-stretching effect decreases with the increase of sheaf strain. For the critical system with a longer terminal Rouse relaxation time, two peaks are observed in the transient shear viscosity. It is also found that, when the shear strain is small, the chain-streching effect on the morphology and the corresponding rheological properties are enhance when the terminal Rouse relaxation time is longer.

Gas holdup in a reciprocating plate bioreactor: Non-Newtonian - liquid phase

The gas holdup was studied in non-newtonian liquids in a gas-liquid and gas-liquid-solid reciprocating plate bioreactor. Aqueous solutions of carboxy methyl cellulose (CMC; Lucel, Lucane, Yugoslavia) of different degrees of polymerization (PP 200 and PP 1000) and concentration (0,5 and 1%), polypropylene spheres (diameter 8.3 mm; fraction of spheres: 3.8 and 6.6% by volume) and air were used as the liquid, solid and gas phase. The gas holdup was found to be dependent on the vibration rate, the superficial gas velocity, volume fraction of solid particles and Theological properties of the liquid ohase. Both in the gas-liquid and gas-liquid-solid systems studied, the gas holdup increased with increasing vibration rate and gas flow rate. The gas holdup was higher in three-phase systems than in two-phase ones under otter operating conditions being the same. Generally the gas holdup increased with increasing the volume fraction of solid particles, due to the dispersion action of the solid particles, and decreased with increasing non-Newtonian behaviour (decreasing flow index) i.e. with increasing degree of polymerization and solution concentration of CMC applied, as a result of gas bubble coalescence.

Surface and Subsurface Cracks in Rolling Contact Fatigue of Hardened Components

The competitive aspect of surface and subsurface fatigue crack propagation in hardened components subjected to rolling contact fatigue is highlighted, the former being greatly affected by the working conditions (in particular the presence of tangential stresses and lubricant), the latter depending mainly on the inclusions content and on the hardness profile. In order to determine which one of these kinds of damage is favoured, initial data consisting of contact load, rolling and sliding speed, theological properties of the lubricant, material hardness and inclusions content are necessary. The concurrent role of asperities and Hertzian stress field in determining surface crack propagation is explained with the approach of the “quiescent zone.” calculating the stress intensity factors range in a contact cycle and considering the pumping effect of the fluid possibly present on the contact surface. Inherent defects (especially oxides) are thought to be responsible for subsurface cracks origin and the Murakami formula for short cracks is extrapolated to describe their growth threshold, which also depends on the hardness and therefore on the depth in surface hardened components. A crack propagation index is then defined as a ratio of applied to threshold stress intensity factor, both for surface and subsurface cracks. Evaluating this index for a general operating condition, it is possible to determine which damage mechanism is favoured, taking into account the decisive effect of the hardness profile. Presented at the 57th Annual Meeting Houston, Texas May 19–23, 2002

DEVELOPMENT OF BATCH EMULSION POLYMERIZATION PROCESSES

Although emulsion polymerization has been used for a long time, relatively little attention has been paid to the technological issues of this polymerization technique. This paper describes the research on chemical engineering aspects of emulsion polymerization in (semi-)batchwise operated stirred tanks. The objective of this work was to improve the operation of current processes and to allow for improvements in the development of novel emulsion polymerization processes. For this purpose, different issues have shown to be important, for which the work described in this paper has been focused on four topics: emulsification, colloidal stability, rheology in high solids polymerization and heat transfer. These topics have been studied using the polymerization of styrene and vinyl acetate as two representative model systems Our results reveal that sufficient emulsification is essential for proper control of the polymerization process. For the emulsifier used in this study, the colloidal stability of the polymer particles is mainly governed by the physico-chemical properties of the reaction mixture. During high solids emulsion polymerization, the particle size distribution of the polymer particles considerably influences the Theological properties of the reaction mixture and thereby the flow pattern in the reactor. Heat transfer to the reactor wall depends strongly on reactor geometry, impeller type and diameter as well as stirrer speed. Additionally, the physical properties of the reaction mixture, being related to solids content, conversion and monomer type, are important for heat transfer.