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Sustainability in pavement construction is very much required in the present scenario. Utilization of industrial waste as pavement material during construction is one of the methods for achieving sustainability. For the present study, Steel Slag and ceramic fibers were used as partial replacement of natural aggregate and as modifiers for binder respectively. SSA at 0, 20 40, and 60% total mix and ceramic additives at 0,3,5, and 7% were used. The rheological properties of the modified binder were studied using a Dynamic Shear Rheometer. Marshall stability test and moisture liability test were carried out to examine performance evaluation. Results show that the mix with 5% ceramic fiber with 60% SSA showed better performance compared to other mixes. [ABSTRACT FROM AUTHOR]

A novel type of magnetorheological (MR) foam that provides unique porous structure with embedded magnetic particles somehow could response to magnetic field stimuli continuously, actively and reversibly. Its low density and controllable properties have rendered MR foam to be a new potential smart material for advance applications such as smart actuators or sensors technology. Unfortunately, the rheological properties in terms of stiffness or known as storage modulus of MR foam is still rather limited, in the range of below than 1 MPa to withstand frequencies with high amplitude displacement during the operational system. Therefore, the aim of this research is to enhance the rheological properties of MR foam in terms of storage modulus by adding silica nanoparticles as an additive. In this study, MR foams were fabricated with different compositions of silica nano-particles in the range of 0 to 5 wt.%, with 1 wt.% increment. The rheological testing was carried out using modular compact rheometer (MCR) under different frequency inputs in the range of 1 to 10 Hz, with the absence and presence of magnetic field at 0 T and 0.8 T, respectively. The finding has revealed that the storage modulus of MR foam has significantly increased up to ∼273% during the off-state condition and further increased to ∼346% at the on-state condition, indicating higher stiffness of MR foam with silica nanoparticles as compared to non-additive MR foam. [ABSTRACT FROM AUTHOR]

This paper presents a data-driven model to predict magnetorheological (MR) grease composition as a function of its rheological properties using several machine learning methods. The methods are Single Hidden Layer Feedforward Neural Networks (SLFNs) and Kernel Based-Extreme Learning Ma-chine (KELM). The approach provides high accuracy prediction and the easiness of changing the inputs or outputs as long as the data is available. While the model output is carbonyl iron particles weight percentage, the model in-puts are the slope of the magnetic field density-dependent-yield stress change over the magnetic fields and the off-state yield stress. The kernel functions are varied from radial basis function, wavelet, linear, and polynomial functions. The simulation results of KELM show that R-squared values are more than 90% for both training and testing data. The root mean square errors also show relatively small values. With a relatively lower number of parameters than SLFNs-ELM, KELM can show comparable performance with SLFNs-ELM and Back Propagation neural networks. [ABSTRACT FROM AUTHOR]

Magnetorheological (MR) material is a smart material composed of one of the magnetic particles of carbonyl iron (CIP) in a non-magnetic medium that can be controlled via magnetic fields. One of the groups of MR materials is MR plastomer (MRP) which consists of CIPs in the low-crosslinking polymer network such as plastomer, and it is introduced to compromise the limitations in MR fluid and MR elastomer. Somehow, the new modern approach particularly machine learning needs to be highlighted to acquire accuracy in the prediction trend of the MRP's properties, including viscosity. In fact, the approach may reduce time and work consuming in the development process of MRP. Therefore, using an artificial neural network (ANN) as one of the machine learning approaches is an effective medium for forecasting the behavior of the material and resolving constitutive model concerns. [ABSTRACT FROM AUTHOR]

Studies on smart materials called Magnetorheological (MR) materials has attracted interest from numerous researchers due to its properties that can be manipulated through applications of magnetic fields. Owing to its wide potential application in various field, improvement on its properties in terms of rheology, tribology, thermal stability as well as electrical conductivity need to be optimized for a material to be possibly applied in real applications. Graphite on other hand is a carbon-allotrope that has been utilized in MR materials which acts as a filler or additives and was reported to significantly improves the distinct properties in different types of MR materials. Therefore, this paper has summarized and discussed the effect of graphite's addition on the properties of several types of MR materials especially on its electrical conductivity, thermal stability, tribological as well as rheological properties to provides an insight view of graphite as a future potential additives and filler in MR materials for upcoming research. [ABSTRACT FROM AUTHOR]

Different fabrication process would result to different properties of material. This is due to the properties of porous materials are highly dependent on its structure. In this study, magnetorheological (MR) foam was prepared via two fabrication processes, namely open mould system and constraint volume mould system which was also known as open-mould (O-MRFoam) and closed-mould system (C-MRFoam), respectively. The characteristics and properties of the fabricated MR foam were presented in this paper. The characteristics of MR foam such as morphological and rheological behavior in terms of storage modulus and linear viscoelastic (LVE) region were experimentally investigated. It can be seen that the properties of MR foam were affected by different fabrication processes. In terms of morphological observation, the average area of pores decreases by 39% when a constraint volume mould system was implied to the fabrication process of the MR foam. It is believed that the distribution of magnetic particles become more compact resulting to more bubble nucleation during the foaming process. As a result, the storage modulus of MR foam was successfully enhanced along with the decrement of the size of pores. Therefore, the results obtained from this study would widen the potential MR foam especially for the use of applications with controllable stiffness. [ABSTRACT FROM AUTHOR]

Environmental effects like rain and temperature as well as the continuous heating phenomenon during device operation are the common factors that will degrade the mechanical and rheological performance of composite rubber materials like Magnetorheological elastomer (MRE) over the time. In this study, the morphological, and rheological properties of the unaged and aged MRE is examined. Two types of silicone rubber based MRE with 30 wt% of CIPs is investigated under the influence of continuous thermal ageing of 100°C for 3 days. Their morphological and rheological properties under the influence of frequency and magnetic field were evaluated using the low vacuum scanning electron (LV-SEM) and rheometer equipped with electromagnetic device. The results revealed that the storage modulus of aged MRE increased with the increment of frequency as compared to unaged MRE. While the MR effect of aged MRE decreased as compared to an unaged MRE. This finding not only provide a better understanding on the influence of thermal ageing phenomenon towards the rheological properties of the MRE but also can be used as an important information for the future device application in MRE. [ABSTRACT FROM AUTHOR]

Shear Thickening Fluid (STF) is a type of Non-Newtonian Fluid whose viscosity increases as the strain rate increases. STF has been applied in various fields, one of which is on soft body armor. STF consists of dispersion medium and dispersed phase particles. Recently, STF does not only consist of 2 phases but is multiphase. Multiphase STF includes the second phase in suspension and in this case the additives particles. Various additives particles (types and properties) have changed the thickening behavior of the STF which increases the ballistic resistance by increasing the density of the suspension and the dynamic strength of the material in the fluid. This review explains the effect of additive particles on the rheological properties of STF and ballistics on soft body armor. Furthermore, the review is also focused on understanding the potential of particle additives in STF and the development of particle additives along with a review towards novelty in the STF field. Furthermore, the focus of this review is the particle additive applied to STF with the literature reviewed relatively recently (last 5 years). [ABSTRACT FROM AUTHOR]

This study is about the comparison between the effect of mixing of surfactant sodium dodecyl sulfate (SDS) and without surfactant on the oxide, which consists of Al2O3, TiO2, and CuO. Obtained by synthesis using a mass fraction of 0.1% SDS and 1 gram of Al2O3/TiO2/CuO dissolved in 1000 ml of distilled water and then stirred using a magnetic stirrer for 1 hour at a speed of 650 rpm. Furthermore, without surfactant, using 1 gram of Al2O3/TiO2/CuO was dissolved in 1000 ml of distilled water and then stirred using a magnetic stirrer. Then the ultrasonic process was for 1 hour to get more homogeneous nanoparticles. The addition of surfactants to nanofluids can increase the stability and viscosity of the nanofluids. Obtained from the results of the Viscometer test with temperature variations from 20 °C-60 °C, the values of viscosity, shear rate, and shear stress. Then tested on Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier Transform Infra-Red (FTIR), and the results of the analysis of Conductivity Thermal and Specific Heat tests. This study aims to determine whether the addition of surfactant to oxide affects the value of viscosity, shear rate, shear stress, and thermal conductivity. [ABSTRACT FROM AUTHOR]

Research on nanofluids has developed rapidly in the application of its heat mechanism to a machine's performance. Heat mechanisms in nanofluids have emerged as promising fluid heat transfers, as for example in applications as a coolant in Thermal Photovoltaic. This study will discuss the effect of the Hybrid Copper Oxide/Titanium Dioxide (CuO/TiO2) Nanofluida on the rheological properties using based water. The purpose of this study was to determine the rheological properties and dynamic viscosity of the hybrid Copper Oxide/Titanium Dioxide (CuO/TiO2) nanofluids based-water performance on system. Hybrid nanoparticles were used to synthesize nanofluids using a volume ratio of 50:50 at 1L of water. Begin by mixing both of nanoparticles CuO and TiO2 with based-water using a magnetic stirrer at a speed of 650 rpm for 60 minutes, then followed by an ultrasonic stirrer for 1 hour so that the two nanoparticles become more homogeneous. The dynamic viscosity obtained using the NDJ-8S Viscometer uses variations in temperature of 20 °C, 30 °C, 40 °C, 50 °C, 60 °C with speeds of 6 rpm, 12 rpm, 18 rpm, 24 rpm, and 30 rpm. The results obtained in the form of viscosity, shear rate, and shear stress. [ABSTRACT FROM AUTHOR]

This research studied the effect of CTAB and PVP surfactants on the rheological properties of DWCNTs and MWCNTs nanomaterials in water-based nanofluids. Surfactants are used to bind between nanoparticles and fluid molecules, because some nanoparticles experience sedimentation on the nanofluid, so the addition of the surfactant is necessary. Mixing is carried out using a magnetic stirrer for 1 hour at a speed of 650 rpm, followed by sonication for 1 hour. This mixing uses a mass fraction ratio of 0.1% nanomaterial and 1:1 surfactant with nanomaterial. Nanofluids were tested by Scan Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infra-Red (FTIR). The NDJ-8S viscometer is a tool for finding the viscosity value of nanofluids with temperature variations of 20 °C, 30 °C, 40 °C, 50 °C and 60 °C using speeds of 6, 12, 18, 24 and 30 rpm. The results of the research included the effect of surfactant and temperature in the nanofluid on the viscosity and shear stress of the DWCNTs and MWCNTs nanofluids. [ABSTRACT FROM AUTHOR]

In this journal, we present about the thermophysical and rheological properties of MWCNT (Multi-Walled Carbon Nanotubes) in Water-Based Nanofluid with various surfactants added. Cetyl Trimethyl Ammonium Bromide (CTAB), Sodium Dodecyl Sulfate (SDS), and Poly Vinyl Pyrrolidone (PVP) are used as a surfactant to be mixed nanofluids. The synthesis was carried out using magnetic stirring and sonicated at 650 rpm for 1 hour with a mass fraction ratio of 0.1%. Then tested on KD 2 Pro Thermal, Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), and X-Ray Diffraction (XRD). Viscosity was searched using NDJ-8S Viscometer with temperature variations of 20 ℃, 30 ℃, 40 ℃, 50 ℃, and 60 ℃ with rotations of 6, 12, 18, 24, and 30 rpm. So that the results obtained the value of thermal conductivity, specific heat, analysis of the surface's topography and composition, phase identification of a crystalline material, functional group, viscosity, shear rate, and shear stress. The result of our research is to be able to choose the best surfactant for MWCNT nanofluids as needed. It is hoped that the selection of appropriate surfactants for nanofluids can be further studied to improve the stability and dispersion of nanofluids for industrial production and long-term use. [ABSTRACT FROM AUTHOR]

In the processing of thermoplastic composites, joining UD tapes to form a layup is a crucial step. In the pick- and-place approach, multiple tapes are spot-welded by a hot stamp. The quality, that is, the bonding strength, of the weld must be sufficient to transport the tape stack to subsequent processing steps. The bonding strength is influenced by hot stamp temperature, contact pressure and time, and rheological properties of the matrix material (viscosity and reptation time). The large number of influencing parameters makes it almost impossible to find optimal settings for time- and energy-efficient processing. To overcome this, we developed a digital model of the welding process that provides information on the bonding of two individual tapes during welding. The model includes the heat transfer between the hot stamp, the tapes, the welding stamp, and the surrounding air. Based on the temperature rise, which affects the rheological properties of the matrix material, the degree of intimate contact and degree of healing are determined, the combination of which gives the degree of bonding. The validity of the model is shown by comparison with data from experiments in which the bonding strength of the welding spots for various process parameter sets was determined by a mandrel peel test. [ABSTRACT FROM AUTHOR]

Depending on the polypropylene composition, chain session and crosslinking are the main degradation pathways of thermo-mechanical degradation during reprocessing. In this study, reprocessing of an impact copolymer polypropylene was investigated. A quad screw extruder (QSE) and twin screw extruder (TSE) were used for reprocessing polypropylene. The reprocessed resins were fractionated and characterized for their rheological, thermal, and chemical properties; zero-shear viscosity was determined from rheological properties. The antioxidant additive levels in unfractionated reprocessed resins were determined. As reprocessing cycles and screw speed were increased in both extruders, complex viscosity and zero-shear viscosity of the insoluble and unfractionated resin fractions decreased, indicating a reduction in polypropylene molecular weight. Compared with the TSE, the QSE produced greater reductions in zero-shear viscosity. With reprocessing, the complex viscosity and zero-shear viscosity of the soluble resin fraction was increased at a low screw speed (500 rpm) as a result of a certain degree of crosslinking, whereas at a high screw speed (1500 rpm), the complex viscosity and zero-shear viscosity decreased with more reprocessing cycles. As a result of degradation, the crystallinity level of the unfractionated and insoluble resin fractions increased significantly due to their greater polymer chain mobility. Analysis of insoluble and soluble fractions by FTIR confirmed no chemical changes were made by reprocessing with TSE and QSE. As expected, there was a reduction in antioxidant additives during reprocessing, but this reduction varied with the antioxidant type, processing method, and screw speed. [ABSTRACT FROM AUTHOR]

In this work, the effect of chitosan molecular weight on microsphere production from chitosan emulsion was studied. The emulsion was produced by the mixing of a water phase (chitosan solution) and oil phase (sunflower and castor oil) to develop mixes of three molecular weights. The morphological and rheological properties of the emulsion were then characterised using digital and optical microscopy and a cone-plate viscometer. The density, surface tension and thermal conductivity of the emulsion were thus tested. The results showed that the viscosity changed according to the change in the molecular weight of the chitosan emulsion, with the diameter, number, and shape of microspheres being strongly related to their rheological behaviours. As the diameter increases, the number of microspheres decreases, and their shapes are less uniform as the molecular weight increases. The formation of microspheres was then numerically simulated utilising a fluent ANSYS 15 program based on the two-phase flow phenomena, with rheological properties used as input data. In terms of the shape, size, and timing of microsphere creation, good agreement thus emerged between the experimental and numerical studies. [ABSTRACT FROM AUTHOR]

Onyx waste from onyx material crafts is utilized as coarse aggregate in concrete mixtures. Onyx waste concrete and standard concrete have different characteristics and rheological properties when viewed from the physical and mechanical properties of the aggregates that form them. Rheological studies of fresh concrete in the onyx waste concrete mixture were carried out by comparing fresh concrete's workability performance and rheological parameters between standard concrete and onyx waste concrete. Concrete slump, slump flow, and compaction factor tests are a series of workability tests carried out to compare the performance of fresh concrete and compressive strength testing to determine the resulting compressive strength. The results showed that the performance or workability of fresh concrete increased with replacing coarse aggregate with onyx stone waste. The slump value increased by 42.42%, the slump flow test increased by 25.974%, 7.142%, and 13.889%, and the factor test compaction increased by 3.557%. Analysis of rheological parameters showed that replacing coarse aggregate with onyx waste reduced the viscosity and yield stress values. The viscosity value and yield stress decreased by 60.261% and 45.970%, respectively. Therefore, it can be concluded that the onyx waste concrete is more manageable to deform than the normal concrete. The compressive strength produced by the onyx stone waste still meets the requirements of the compressive strength criteria as structural concrete. [ABSTRACT FROM AUTHOR]

Mine transport in its hydraulic form have been attracting more and more industries. In this work, we discuss challenges related to the transport of Phosphate in its slurry form. This dynamic is highly non-newtonian and very little knowledge about its rheological properties is available. For that purpose, we examine the ability of machine learning tools to predict these information using available real data. This dataset includes information about rheology but also many physico-chemical parameters such as the density, the soli concentration the particle size distribution among others. Three well-known machine learning algorithms are tested. Despite an important overfitting observed due to the limited amount of data, the results are encouraging and pave the way towards predicting with reasonable accuracy the hydraulic of the Phosphate slurry fluid in pipelines. [ABSTRACT FROM AUTHOR]

Agricultural products often experience damage due to mechanical forces in harvesting, transportation, sorting, and storage. Knowledge of the nature of agricultural products in terms of rheological property is essential in designing agricultural machinery to determine the required parameters. Measurement of creep test may provide information related to the rheological properties of the product. The objective of this study was to investigate the effect of maturity level and size on the rheological properties of tomato fruit. The research was done using three different tomato maturities of green, turning, and red and three sizes that were small, medium, and large tomatoes. Those samples were subjected to a creep test with an initial load of 30 N for 15 minutes. The results of this test were then used to determine the constants of the four elements of Burger's model to represent the rheological properties of the samples. The results indicated that the large green tomato consistently had the smallest values of J0, J1, and η0. The value of Tret for green tomato tended to be the largest one. These results indicated that green tomatoes tended to have a smaller change of strain than turning and red tomatoes at any time during the creep test. Maturity level significantly affected the values of J0, J1, η0, and Tret. Tomato size significantly affected J0, J1, and η0 but did not affect the Tret. However, there was no significant interaction between the level of maturity and tomato size to the Burger's model constants values. The four elements of Burger's model were found to be suitable to predict the change of tomato strain during the creep test. [ABSTRACT FROM AUTHOR]

In present study the effect of adding discarded steel fibers from tires manufacturing (DSF) on rheological, hardened properties, and flexural toughness of self-compacting concrete is investigated. In this regard, four SCC mixes were prepared using four contents of DSF which are 0%, 0.5%, 0.75%, and 1% with 40mm fiber length. The rheological and hardened properties were evaluated by conducting slump flow, T500, L-box, segregation index, density, UPV, compressive strength, splitting tensile strength, modulus of elasticity, and flexural toughness tests. The rheological properties were found to be affected adversely. However, all results were compiled to European guidelines limitations. On the other hand, it was observed that adding 1% of DSF gives the best mechanical performance where density, compressive strength, tensile strength, and modulus of elasticity increased by 1.64%, 12.3%, 95%, and 7.77%, respectively. Furthermore, the flexural toughness indices were found to be increased significantly by 377%, 738%, and 1171% for I20 for the aforementioned mixes as compared to plain mix, where residual strength was increased greatly which indicates better performance after cracking. Finally, based on the abovementioned findings, adding DSF into SCC has contributed in enhancing its performance greatly, which worth to be further investigated. [ABSTRACT FROM AUTHOR]

Ceramics are used as a body, filler, and coating material, which helps strengthen and beautify buildings or filled/coated material. The material for the manufacture must be carefully selected to meet the predetermined criteria. The main ingredients for making ceramics are clay and feldspar, which in this research uses SiO2. The supporting elements added are water glass and water. In this study, the effect of SiO2 composition was observed in 6 samples, consisting of 3 samples with additional SiO2 composition and another 3 samples with additional clay. The physical tests performed were rheology, residues, shrinkage after drying and firing, water absorption, loss on ignition (LOI), and bending strength. The test results show that additional SiO2 composition will reduce viscosity, LOI, shrinkage, and bending strength but increase the residue. On the contrary, additional clay composition will increase viscosity, LOI, shrinkage, and bending strength but decrease residue. The addition of SiO2 as an additive in filler material at a certain percentage is considered as it has lower LOI and shrinkage values. However, from an economic point of view, additional SiO2 also needs to be considered as it is more expensive than clay. [ABSTRACT FROM AUTHOR]

Polymer flooding has shown to be effective in Enhanced Oil Recovery (EOR). In recent years biopolymers have attracted the attention of the petroleum Industry. Recently, it was identified that using biopolymer schizophyllan for polymer flooding operations has advantages primary benefit being environmentally friendly factor as well as stability under high salinity and temperature conditions. This biopolymer is commercially produced from the fungus schizophyllum commune using glucose as a carbon source via a fermentation process. However, the processing of this biopolymer is not economical due to the sources utilized in its production. This study aims to investigate the biopolymer schizophyllan produced utilizing locally and cheaply available sources in Malaysia for its rheological property at various range of salinity and temperature conditions. The experimental results showed that, viscosity of schizophyllan remains independent of salinity because of its non-ionic nature. Further, it was found that the loss in viscosity at high temperature was insignificant. This study will provide an alternative schizophyllan biopolymer from local sources that has potential in terms of properties and economics, making it available at any time of year and contributing to the field of polymer flooding. [ABSTRACT FROM AUTHOR]

Formulating a good drilling fluid is the key factor to the success of any drilling operation. There are many problems that occur during drilling operations that reduce the efficiency of the mud such as low lubricity problems. Oil based mud (OBM) can be used to reduce the effects of the mentioned problem compared to water-based mud (WBM). However, due to the environmental and economic factors, the usage of OBM is limited. Hence, this study was conducted to improve the lubricity of WBM using nanomaterials. Two nanomaterials have been used which are graphene nanoparticles (GNP) and titanium dioxide (TiO2) with varying the concentration from 0 – 1.0 g. The rheological properties, API filtration and mud cake thickness at room temperature and after aging at 250⁰F for 16 hours were tested. It was found that the addition of nanomaterials reduced the coefficient of friction (CoF) of the WBM up to 35%, where the reduction increased with raising the concentration. GNP showed more prospective reduction of CoF of WBM compared to titanium dioxide. [ABSTRACT FROM AUTHOR]

In this work, the colloidal-chemical, rheological properties of a liquid material for electromagnetic fields shielding with different contents of Fe-containing shielding filler are studied. Changes in a density of the protective composition and dynamic viscosity were determined depending on the concentration of the Fe-containing filler. Equations describing these dependencies are presented. These dependencies influence the choice of the method of applying protective compositions to the substrate surface. It has been shown that at filler concentrations of 15% and 30% (by weight) they can be applied to the surface by brush or spraying. At concentrations of 45%, it is advisable to apply with a roller, 60%-with a spatula. The wetting angles of the protective composition applied to wood and drywall for various filler concentrations are determined. It is shown that the change in the surface tension with an increase in the filler concentration occurs non-monotonically. The minimum surface tension corresponds to a concentration of 30%. At a concentration of 60%, the surface tension increases by 1.2 times in comparison with the initial value of the surface tension of the initial water-dispersed binder. It was found that an increase in the spreading coefficient leads to a more complete wetting. The paper presents complete data on the dependence of the surface tension on the filler concentration, the average wetting angles, the work of forces of adhesion, cohesion and wetting, the wetting and spreading coefficients. [ABSTRACT FROM AUTHOR]

By following the expression of the binding force of the molecules (resistance of fluid to flow) under controlled pressure and temperature conditions and the influence of the characteristics on the efficiency of the components of the hydraulic mechanism, one can evaluate the compatibility and optimize the potential of the lubricating fluid (subjected to physical-chemical stress) and its impact (toxicity and loading) on the environment after the cycle of use. Phenomena inside the lubricant layer have a great influence on lubrication, as a result of the association of molecules under the action of existing polar substances, but also through intra-molecular friction. The phenomena occurring at the friction surface, at the micro level of the peaks in contact, where the temperature and pressure are significantly increased, can be studied and diminished to reduce energy losses, by creating a protective layer, thus providing better resistance and elasticity of the molecular contact surface. Starting from the aspect of element interactions and the study of chemical transformations between friction surfaces and reaction media, the action of (tribological and rheological) phenomena on the durability of mechanical systems can be analysed and developed. This action can be carried out through mathematical modeling and parameter calculation methods, which define the phenomena that take place at the collision, for the extension and improvement of the experiments at the prototype level. The cumulative influence of the phenomena inside the lubricant layer with those occurring at the lubricant-metal interface is determined by the surface properties of the lubricant but also by the attraction forces from the surface of the metals with which the lubricant is in contact. [ABSTRACT FROM AUTHOR]

Nowadays it is state of the art to review, assess and solve problems in all phases of an injection molding process by using the injection molding simulation software such as Moldex3D, Moldflow and Sigmasoft. In order to receive good injection molding simulation results, it is necessary to have a correct and complete material properties. The required material properties for the simulation processes of the injection molding include value of heat capacity and thermal conductivity, a viscosity model and its fitted parameters, a pressure-volume-temperature (PVT) model and its fitted parameters. Especially in the injection molding simulation of thermoset materials it requires defining information about a curing model and its fitted parameters. The material properties in the simulation processes of thermosets injection molding are now found in limited sources and are seldom available from data bank of simulation software. This is because the generation of material properties requires comprehensive knowledge not only in the measurement of reactive viscosity and thermal properties, but also in the field of mathematics such as optimization algorithms. In this research, the fitting tool called Thermoset – TU – Fitting tool has been developed by authors to investigate and evaluate the adaptation of different reactive viscosity models and cure kinetics models in the viscosity and curing kinetics characterization of reactive injection molding materials. Consequently, the material properties of some commercial thermoset materials for the simulation processes of reactive injection molding were successful created with the optimal cure kinetics and reactive viscosity model. A remarkable agreement between simulation results and experimental results shows that it is possible to use Thermoset – TU – Fitting tool to generate the material properties for the simulation processes of the reactive injection molding in a reliable and fast way. Thermoset – TU – Fitting tool is now a package available to all the scientific and industrial community through Professorship of Plastics Engineering, TU Chemnitz. [ABSTRACT FROM AUTHOR]

This work deals with the study of rheological properties of two types of elastomeric blends. Rheological properties such as shear rate, shear stress and dynamic (shear) viscosity of two types of elastomeric blends with a different compositions were measured. The properties were determined by capillary and oscillating rheometer under laboratory conditions and also by using an extruder under operating conditions. The work was mainly focused on determining of the deviation of elastomeric blends from Newtonian fluid flow, which was determined on the basis of obtained graphical dependences of blends from measured rheological parameters using different types of rheometers and a wide range of shear rates. Since elastomeric blends are considered to be pseudoplastic fluids, the shear viscosity values showed a decreasing tendency with increasing shear rate. Blend 1 has better flow properties and thus processing properties because the deviation from the Newtonian flow is smaller and closer to the ideal fluid flow. Blend 2 contains a higher proportion of natural rubber, and thus shows higher stiffness and poorer processability. [ABSTRACT FROM AUTHOR]

This study deals with the influence of the alternative filler content, as a partial replacement of the commonly used filler - silica, on the process of mixing elastomeric blends and subsequent vulcanization. Commonly used fillers such as silica and carbon black often increase the temperature of the blends during the mixing process due to their reinforcing properties and low particle size, which leads to the need of cooling the elastomeric blend during the mixing process while limiting the addition of materials sensitive to high temperatures (e.g. vulcanization system). As alternative filler, a by- product from industry was used, the so-called energy gypsum, which the effect of on the vulcanization process has already been investigated by the authors. However, the direct effect of this alternative filler on the mixing process of elastomeric blends has not yet been studied. Using the Winmix program, which is used to directly record the magnitude of torque and temperature during the mixing process, the influence of the silica content and energy gypsum on the stated parameters of elastomer blends mixing was studied. For systems with different ratio of the given fillers, their influence on rheological properties and vulcanization characteristics was also evaluated. The results of the study provide important knowledge about the influence of conventional and alternative fillers on the mixing process and vulcanization of elastomeric systems and in the future will serve to set and optimize the parameters of these processes. [ABSTRACT FROM AUTHOR]

Plasma technology based on diffuse coplanar surface barrier discharge DCSBD represents novel method of economic, efficient and versatile way of materials treatment. As the example of atmospheric pressure plasma source finds an application in modification of wide surface areas within high speed and enables homogenous in-line plasma treatment. Also, the technique of DCSBD plasma is known for its usage and testing in environmental, bio-medical and industrial areas. Also, it is capable of producing various types of active particles e. g. electrons, atoms, ions, radicals, photons, etc. in different processing gases. The focus of this paper was aimed at the modification of unvulcanized rubber blend by diffuse coplanar surface barrier discharge in order to improve the rheology and physical mechanical properties. Also, the impact of plasma on structural properties of raw rubber blend was studied and the effect of the possible surface crosslinking. [ABSTRACT FROM AUTHOR]

The presented paper is focused on the effect of the wood flour on the rheological and mechanical properties of elastomer blends. The mentioned wood flour comes from the production of wood pellets. Wood flour can be used as an alternative plasticizer in the elastomer mixture due to the lignin content. Lignin is the less polar than cellulose and acts as a chemical adhesive agent. The wood flour and other lignocellulosic fibers can be easier incorporated as a plasticizer with other ingredients into a rubber compound. Plasticizers (also called softeners, extenders or process oils) are the additives for polymers with a low molecular weight. An increasing content of a plasticizer usually leads to decrease in viscosity of the rubber blend, and therefore, the processability can be improved. The influence of the wood flour and its different particle sizes on rheological properties of elastomer blends and mechanical properties (hardness, tensile properties) of vulcanizates were studied. The obtained research results, especially the Paine effect and mechanical properties, show that the alternative additive based on wood flour does behave like a filler, but with an additional significant plasticizing effect that increases with the reduction of the wood flour particle size. The results thus show the possibilities of plasticizer replacement for studied wood flour in the elastomer blend. The results of this research can also bring environmental benefits in the form of removing petroleum products from the production of rubber. [ABSTRACT FROM AUTHOR]

Economic development forces an increase in the need for transport services. In Poland, the dominant branch of transport is road transport, which accounts for over 85% of the weight of all transported loads. The increase in the number of delivery vehicles and trucks on the roads increases the threats to the safety of people, the environment and property. The key issue of the safety of goods transport is the proper securing of the transported cargo. The article indicates the threats resulting from improper securing of cargo. The method of testing lashing straps in various environmental conditions is presented. The obtained results confirm the existence of a relationship between humidity and mechanical and rheological properties of the belts. The obtained results will be used to build a numerical model and to simulate the behavior of lanes in changing weather and road conditions. [ABSTRACT FROM AUTHOR]

The impact of the rheological properties of self-compacting concrete SCC both in dynamic and static state on the evolution of formwork pressure over time at different casting rates was investigated. It is demonstrated that in terms of formwork pressure the ability of structure build-up expressed by static yield value gs is crucial. The influence of dynamic yield value g is significant only in the initial phase of casting. Higher plastic viscosity h and thixotropy factor AT delay the SCC structure build-up and contribute to increased pressure on formwork. The effect of casting rate on formwork pressure is discussed in relation to the rheological properties of the SCC and its changes over time. The formwork pressure of SCC at the same casting rate is the lower the higher is the surface module of the formwork. [ABSTRACT FROM AUTHOR]

The evolution of formwork pressure generated by SCC of different composition at various temperatures from 10 to 30°C was investigated. Both temperature and w/c influences static yield stress gs and thixotropy factor AT of SCC, with a more important factor being the w/c. Static yield stress gs of SCC is higher the higher the w/c and the temperature are. Static yield stress gs nonlinearly increases in time, slows down with time. Thixotropy factor AT of SCC decreases with temperature decrease. Initially, the pressure of SCC on the formwork is directly proportional to the temperature of the SCC as dynamic yield value g decreases with increasing temperature. After 20 minutes, the pressure on the formwork of the SCC is inversely proportional to the temperature. SCC at higher temperatures faster build-up a structure capable of carrying loads and obtain higher static yield value gs. [ABSTRACT FROM AUTHOR]

Viscoelastic properties of solutions of entangled wormlike micelles of anionic surfactant potassium oleate were investigated in the presence of hydrophobically modified polyacrylamide (HM PAAm) at different compositions. It has been shown that HM PAAm increases the plateau storage modulus and the zero-shear viscosity by several orders of magnitude because of physical crosslinking of the micellar chains as a result of penetration of hydrophobic side groups of the polymer into the micelles. The observed direct influence of a number of hydrophobic groups of polymer on the rheological properties confirms the polymer-surfactant interaction. The effect of polymer decreases with increasing surfactant concentration, when branched wormlike micelles are formed instead of linear ones. The increase of the plateau storage modulus and the zero-shear viscosity with addition of HM PAAm were observed both below and above the overlap concentration of polymeric chains. In the last case, the hydrophobic side groups of the polymer can form domains reinforcing the polymer-surfactant network. [ABSTRACT FROM AUTHOR]

The so-called 'complex fluids' have mechanical properties unlike those found in either Newtonian fluids or elastic solids. Their study is known by the term rheology. Materials we deal with in real life are usually far from ideal liquids or solids. Therefore, obviously, the study of such materials is an important field of research. Squeeze flow, as the term implies, is a study of the simple process of squeezing a fluid between two solid surfaces. Wetting and spreading properties of the fluid with respect to the substrate and the rheology of the fluid determine the results of this experiment. In this context Gelatine gel under the squeeze flow is reported here. Complex oscillatory shear thinning behaviour is observed and reported. [ABSTRACT FROM AUTHOR]

Many of the research and investigations carried out to replace or reduce the fresh bitumen that uses in pavement construction as a binder due to rising the cost of crude oil production employed in bitumen manufacturing. This research seeks to determine the impact of employing bio-oil, namely waste vegetable oil (WVO), on the properties of bitumen, with the ultimate goal of improving bitumen's performance. The standard tests that were used to evaluate the physical and rheological properties of the control and WVO binders are penetration, softening point, viscosity, loss on heating, and dynamic shear rheometer (DSR). In order to assess WVO effectiveness, two different penetration grades 60/70 and 80/100 asphalt binders were modified with WVO at different percentages (1.5%, 3%, and 4.5% by weight of the binders). According to the results of the tests, the penetration values rose as the quantity of WVO in the binder increased, however, the softening point result decreased as the amount of WVO in the binder increased. With a rise in the amount of WVO in the binder, the viscosity of the binder was reduced. With increasing WVO, the rutting parameter decreased. As a result of this research, it was determined that waste vegetable oil has the potential to affect soft asphalt binders and can be used to make soft asphalt binders. Furthermore, by adding 4.5% WVO to a PEN60/70 asphalt binder, it can become a PEN80/100 asphalt binder. [ABSTRACT FROM AUTHOR]

The black cementing material known as asphalt has been used for road construction for centuries. Asphalt mixtures have greatly evolved from their beginning in the late 19th century to modern. The binder serves two purposes; one is to glue the aggregate together, and the other is to protect the aggregate from environmental distresses. Bitumen possesses a strong temperature dependence of rheological properties, governed by the interaction of the individual constituents. Inadequate properties of bitumen can lead to the extremely problems with the asphalt mixture. The work presented here is a real proof of how an inadequately well-treated asphalt or an unprofessional approach to pumping can cause huge problems in the production of asphalt mixtures. [ABSTRACT FROM AUTHOR]

This paper is an experimental study regarding activated carbon of peanut shells on rheology and filtration loss of drilling mud. Rheology and filtration loss are essential characteristics of mud that in controlling the accomplishment of drilling operations. This research begins by activating carbon from peanut shell waste (KKT) with three different activation temperatures, e.g., 700, 800, and 900°C. We conduct Rheology, i.e., absolute, plastic viscosity, yield point, and gel strength, to observe the effect of carbon activation temperature of KKT additive to those parameters. Moreover, filtration tests to determine mud-cake thickness also become one part of this study. The results showed that the mud sample with 5 g KKT activated carbon at 900°C activation temperature shows the best performance among all samples. Result from both rheology and filtration test yields 5 cp plastic viscosity, 10 yield point, 0.4 gel strength, the volume of the filtrate is 16 ml, and the mud cake is 0.16 cm. [ABSTRACT FROM AUTHOR]

The current concrete industry is closely related on the massive use of various chemical admixtures, which significantly modify the properties of fresh and hardened concrete. The plasticizers have crucial sense for the production of concrete structures. This paper is dealing with the study of rheology properties of Portland cement paste with an increasing dosage of naphthalene plasticizer. The experimental study was focused on the systematic description of the rheology properties in terms of shear stress and viscosity. The data obtained were expressed by a pseudoplastic model, which exhibited the best fit. The results confirmed essential influence of the studied plasticizer on the rheology properties of fresh pastes. Both studied parameters, thus consistency coefficient and power index, increased with a rising dosage of the studied plasticizer. [ABSTRACT FROM AUTHOR]

This work expands on the knowledge of cementitious composite materials suitable for 3D robotic processing gained from previous research and focuses on the significant physical and thermophysical properties of these composites. In particular, the determination of these properties and their importance for individual 3D processing technologies. In this research, the composites were optimized for robotic sculpturing and for 3D printing. The aim is to achieve an optimal ratio between the desired rheology of the fresh mixture and the resulting mechanical and physical properties for a given type of robotic processing. [ABSTRACT FROM AUTHOR]

Glass Fiber Reinforced Polymer (GFRP) reinforcement is currently used instead of traditional steel reinforcement in concrete structures. At the same time, rheological properties of GFRP reinforcement, which also determine service life, reliability, and sustainability of structure, are studied insufficiently. Creep rupture factor for GFRP rods prescribed by current design guidelines is rather conservative. Besides rather strict requirements for achievement of serviceability limit state mentioned documents put additional limits on calculation for long-term load. Taken factors significantly decrease design values of reinforcement characteristics. The purpose of this article is to investigate the stress strain state of concrete beams reinforced with GFRP during long-term four-point bending. Article describes methods and results of experimental research for strain and deflection growth in time, crack formation and residual strength of beams designed to achieve flexural behavior. 6 beams (3 series) with GFRP 6 and 14 mm in diameter were exposed under constant loads for 175-200 days. After exposure for 175-200 days all beams were tested by short-term four-point load to achieve flexural failure in cross section. Result of this work, presented in tables and figures, describes creep parameters (ratio of creep deflection) of the concrete beams reinforced with GFRP. Deflection of a beam considering the creep was obtained based on test results. [ABSTRACT FROM AUTHOR]

The problems of modeling the processes of destruction, crack formation, their development and propagation are relevant in a variety of applied fields: dynamics and strength of machines and mechanisms, mechanics of structural materials, biomechanics and forensic examination, etc. Currently, there is a large number of physical and mechanical-mathematical models describing the process of destruction of various materials. In addition to the fracture criteria, it is also important to correctly take into account changes in the rheology of the fractured material, including the contact interaction between the surfaces of cracks and fragments. This paper proposes a numerical approach to solving the problems of contact interaction and brittle fracture of elastically deformable bodies. Crack bank interactions, including frictional forces and contact pressures, is modeled by the means of frame-type contact finite elements (CFE) using a stepwise analysis method. Various contact conditions – separation, clutch, friction-sliding, as well as rheological properties of crack surfaces and fragments – contact layer pliability, adhesion strength, etc. are modeled with the help of CFE. The proposed approach was used in the numerical modeling of bone damage under the penetrating action of a rigid indenter. The conducted numerical studies have shown a good correspondence of the calculated and experimental results, despite the substantial approximation of the used calculation schemes. [ABSTRACT FROM AUTHOR]

Many researchers have proposed various alternative solutions to reduce various flexible pavement failures such as fatigue, rutting, and low temperature cracking over the past decades; however, pavements in Iraq still succumb to early failure as a result of increasing traffic volumes, axle loads, truck tire pressures, and atmospheric temperatures, despite the use of various modified mixtures and asphalt materials for improving the foundation. The goal of this study is to see how well asphalt concrete mixtures with nano-silica (NS) additions perform in road pavements. The SuperpaveTM experiments were used to study the rheological properties of the asphalt binder by the rotational viscosity value, penetration test. Asphalt containing NS of 2 %, 4 %, and 6% by bitumen weight mixing by high shear mixer for 60 min at 2000 rpm to prepare a homogeneous composite overall. the addition of Nano silica has a helpful influence on the rheological properties of the modified asphalt binder. The performance characteristics of the used bitumen mixes based on Marshall, indirect tensile strength, wheel tracking, and moisture susceptibility tests. According to the findings, the best NS content is 6% by weight of asphalt. By adding 6% NS to the asphalt mixture, the Marshall stability is increased by 48%, the flow is reduced by 20%, the unit weight is maintained, and the amount of air voids in the mix, as well as other mix qualities, are kept at acceptable ranges. It'll also boost the ITS by 89%. In general, adding NS to asphalt mixtures improves their qualities. Improves rutting performance and reduces rut depth by 86% at 6% (NS) making it suitable for constructing highway flexible pavements in hot weather. [ABSTRACT FROM AUTHOR]

The effect of ultrasonic treatment of sulfur melt on its rheological properties has been studied. It has been proven that under the influence of ultrasonic treatment, the viscosity of the sulfur melt can decrease or increase depending on the parameters and exposure time. Sulfur was studied before and after ultrasonic treatment by the methods of electron paramagnetic resonance, X-ray phase analysis. The optimal duration of ultrasonic treatment has been determined for conducting processes with maximum viscosity, as a result of which the formation of polymeric sulfur is possible. Sulfur composite materials were obtained using ultrasonic treatment. Materials of optimal composition have high strength, low water absorption capacity and are resistant to aggressive environments. A fundamental technology for obtaining polysulfide composite materials using ultrasonic treatment is proposed [ABSTRACT FROM AUTHOR]

In this paper, the influence of aluminum-containing nanotechnogenic raw materials and pyrophyllite on the structural and rheological properties of ceramic masses for the production of acid-resistant materials and on their physico-mechanical and chemical parameters and porosity structure is discussed. Ceramic masses for forming prototypes were prepared from the clay part of the gravity "tails" of zircon-ilmenite ores, nanotechnogenic raw materials (Dead catalyst) and pyrophyllite. Studies of the effect of the amount of Dead catalyst and pyrophyllite in a ceramic mixture on structural and rheological parameters were carried out on eight different compositions. The plasto-visco-elastic properties of the compositions were determined at a humidity corresponding to the molding, at W=22%. The physico-mechanical parameters of acid-resistant tiles of the ART-1 type (0,1×0,1×0,02 m in size) fired in the temperature range of 1250-1300°C were determined experimentally. The study of the structure of the samples and photographing of the micro relief of the surface were carried out using an electron microscope JEOL-6390A. The use of nanotechnogenic raw materials contributes to the improvement of physical and mechanical parameters. Studies have shown that the presence of isometric pores and oval closed porosity, in contrast to elongated (slit-like) pores, in ceramic materials give them mechanical strength. [ABSTRACT FROM AUTHOR]

The mineral attapulgite clay consist of hydrated magnesium aluminum silicate. Bahr-Al-Najaf region located mid-south of Iraq, has attapulgite clay stone, which composed of calcite and quartz mineral (43.4% and 13.9% weight respectively). The aim of current study was to create mud made of attapulgite met the criteria of (API) American Petroleum Institute to use as mud for oil well drilling in the clay of Bahr Al-Najaf, as well as to develop acceptable oil well drilling mud out of Bahr Al-Najaf clay. To achieve this purpose, the attapulgite rods should be disseminated and quartz particles and calcite with diameters higher than 75 m should be eliminated. Making attapulgite mud appropriate for drilling mud in oil wells, wet sieving was employed to clean up. This procedure improves rheological and filtration qualities by making it ideal to prepared MgO and TiO2 Nanoparticles (NPs) as well as the production of oil well drilling mud. X-Ray diffraction (XRD) and Field-Emission Scanning Electron Microscopy (EF-SEM) measurements were used to assess metal shape and characteristics. Ofite viscometer was used to measure the attapulgite of rheological characteristics. MgO and TiO2 NPS was added to the attapulgite with three different quantities (0.08, 0.05 and 0.02% wt), However, the final result of the process under consideration. MgO contributed significantly to viscosity improvement, with the electrostatic attraction between positively charged magnesium oxide and negatively charged palygorskite rods being the fundamental mechanism. The structural inversion of palygorskite rods is influenced by this coupled force, which has even resulted in flocculation reinforcement. According to the findings, the use of TiO2 nanoparticles enhanced the results. [ABSTRACT FROM AUTHOR]

The Natural Rubber (NR) blend with Styrene-Butadiene Rubber (SBR) loaded with different fraction ratios of NR were prepared. Various ratios of NR namely 25-55 part per hundred rubber part (phr) were prepared. The ratios of SBR ranging 45-75 phr from the masterbatch were blended. The rheological and mechanical properties of pure blends and those loaded with different fraction ratios of NR were investigated. Rheological properties analysis has been showing improvement in most blend ratio until 40 phr NR. Parameters such as initial, minimum and maximum torques, Mooney viscosity, and thermo-plasticity were recorded. The overall enhancement is observed in cure rate and induction time in relation with NR loading up to 50phr NR, then declined in above this ratio. The mechanical properties, namely hardness, tensile strength, and Young modulus were improved as NR content increases to nearly 40 phr NR while elongation improved by 35% only. The young modulus results show random behaviour and the maximum value was at the content of 40-45 phr NR. Accordingly, the 40 phr NR blend was found to exhibit the highest values of the most rheological and mechanical properties. [ABSTRACT FROM AUTHOR]

High performance epoxy resins, pure or in combination with other materials like carbon fiber or fiberglass, are important materials for a wide range of applications and especially for automotive and aerospace industries. To ensure advanced materials with exceptional strength, durability and versatility for a wide range of applications, formulation knowledge and control over curing time and temperature are essential. To characterize the behavior of epoxy resins before, during and after curing, a rheometer has been used. The curing involves a gradual change in the rheological properties (macro-properties) of the sample as a direct consequence of the chemical reaction in which the epoxy and hardener are converted into a three-dimensional network. The Winter-Chambon criterion, based on a dynamic multiwave test, was used to determine the sol/gel transient point, also called gel point. The transition from liquid-like to solid-like behavior can be additionally monitored by dielectric spectroscopy, were the changes of the dipole's mobility reflect the progress of the curing reaction. Additional information is gained by Raman spectroscopy, providing a unique fingerprint of functional groups and the chemical backbone structure of the material. Besides, Raman spectroscopy give further information about chemical reaction rate, pot life and curing times, or the presence of intermediate or by-product species. [ABSTRACT FROM AUTHOR]

The rheological and self-healing behavior of a class of catalytically synthesized amine functionalized polyolefins is investigated. These materials possess tunable rheological properties and display autonomous self-healing. The linear viscoelastic properties are modelled using a tube based Time Marching Algorithm to calculate several model parameters that describe the individual chain dynamics. The self-healing response is described by findings from the reptation model as well as recent theory on associating polymer networks with reversible bonds. [ABSTRACT FROM AUTHOR]

Injectable hydrogel systems are the current interest in health care or medical field for therapeutic agent delivery, disease/cancer therapy, and tissue engineering. On the other hand, polysaccharide-based hydrogels are appealing materials for biomedical applications due to their polyfunctionality, biodegradability as well as originality (origin from nature). Hence, attention has been given in preparation of polysaccharide based injectable hydrogel. But the stability, usability, and application of injectable hydrogel in the biomedical field is determined by rheological properties, which is the most significant features of injectable hydrogels. This article reports about rheological behaviors such as storage (G') and loss modulus (G"), complex viscosity, shear stress and gel point of polysaccharide based injectable hydrogels prepared with oxidized bacterial cellulose, pectin, and chitosan, designated as S-0.5, S-0.75, S-1.0 and S-1.5. They appeared as transparent white, self-crosslinked, and soft polymeric gel with gel formation within less than 30 second possessing depicting viscoelastic properties under oscillatory shear deformation. [ABSTRACT FROM AUTHOR]

Understanding the effect of branching on the melt rheological properties in shear and elongational flow is of fundamental interest to polymer science. Besides the number and the molecular weight of the arms as well as of the backbone, the exact location of the branching points, thus the exact topology is key to control shear and extensional rheological properties. Fourteen low-disperse, polystyrene pom-pom samples were synthesized with two optimized synthetic routes via a combination of anionic polymerization and grafting onto, in a scale of up to 300 g per model system. The molecular parameters of the pom-poms such as molecular weight of the backbone (MW,b=100 - 400 kg.mol−1), of the arms (MW,a=7 - 300 kg.mol−1) and the arm number at each end (q=5 - 30) are systematically varied. The shear and elongational behavior are investigated experimentally and analyzed within the framework of the pom- pom model. High shear thinning is found in small amplitude oscillatory shear (SAOS) measurements. The results in shear revealed up to five times lower zero-shear viscosities for pom-poms compared to combs with similar MW,b, MW,a and total arm number. For the pom-poms, maximum strain hardening factors beyond 100 are found in elongation, depending for the pom-poms exclusively on the total arm number, as the elongational viscosity is by a factor of [q²/ln(√3×q)] above the linear-viscoelastic envelope (LVE) in the backbone rubber plateau, as predicted by the pom- pom model and the Considère criterion. [ABSTRACT FROM AUTHOR]