Search

The transport structure of any company includes marine transport, whose engines use marine fuel and fleet fuel oil. Both types of fuel contain heavy oil fractions, the use of which causes environmental problems: high emissions of pollutants during engine operation, carbon dioxide emissions, accidents and pollution of water with oil products, etc. At the same time, each of these fuels contains a diesel fraction. This article proposes to replace the petroleum diesel fraction with biodiesel fuel obtained from renewable resources, since its characteristics are as close as possible to the quality indicators of the petroleum diesel fraction. This reduces harmful emissions when large amounts of fuel are burned in marine engines. In the event of an accident or a spill, unlike petroleum products, biodiesel fuel decomposes on its own within a few months. The cost of environmentally friendly marine fuel will be lower than the cost of low-viscosity marine fuel made from petroleum components. [ABSTRACT FROM AUTHOR]

Hypothesis: Capillary suspensions offer a new approach to generate novel materials. They are ternary liquid-liquid-solid systems characterized by particles connected by liquid bridges of one fluid suspended in a second immiscible bulk fluid. The viscosity of the bulk liquid can be modulated to customize the structure and rheological properties of capillary suspensions. Experiments and simulations: Using experiments and numerical simulations, we investigated capillary suspensions in the pendular state, using silica particles and water as a bridging liquid. To modulate the viscosity of the bulk fluid, we use different ratios of either dodecane and diisononyl phthalate, or silicone oils with varying chain lengths as bulk liquids. The rheological behavior was characterized using the maximum storage and loss moduli and the yielding behavior. This was related to structural changes of the systems, which was visualized using confocal laser scanning microscopy. In addition, we used Molecular Dynamics (MD) simulations to gain more insights into the behavior of two particles connected by a liquid bridge for various bulk liquids. Findings: Experiments show that higher bulk liquid viscosity reduces strength, yield stress, and yield strain in capillary suspensions, which is partly attributed to a reduced inter-connectivity of the percolating network. This is caused by the breakup of liquid bridges occurring at shorter distances in the presence of highly viscous bulk liquids, as indicated by numerical simulations.   [ABSTRACT FROM AUTHOR]

We prove that if u ∈ C 0 (B 1) satisfies F (x , D 2 u) ≤ 0 in B 1 ⊂ R 2 , in the viscosity sense, for some fully nonlinear (λ , Λ) -elliptic operator, then u ∈ W 2 , ε (B 1 / 2) , with appropriate estimates, for a sharp exponent ε = ε (λ , Λ) verifying 1.629 Λ λ + 1 < ε (λ , Λ) ≤ 2 Λ λ + 1. The upper bound is conjectured to be the optimal one. Thus, the main new information proven in this paper is that the sharp Hessian integrability exponent for viscosity supersolutions in the plane remains at least 81.45% of its upper bound. This greatly improves previous known estimates. [ABSTRACT FROM AUTHOR]

This paper considers the Keller-Segel model coupled to stochastic Navier-Stokes equations (KS-SNS, for short), which describes the dynamics of oxygen and bacteria densities evolving within a stochastically forced 2D incompressible viscous flow. Our main goal is to investigate the existence and uniqueness of global solutions (strong in the probabilistic sense and weak in the PDE sense) to the KS-SNS system. A novel approximate KS-SNS system with proper regularization and cut-off operators in H s (R 2) is introduced, and the existence of approximate solution is proved by some a priori uniform bounds and a careful analysis on the approximation scheme. Under appropriate assumptions, two types of stochastic entropy-energy inequalities that seem to be new in their forms are derived, which together with the Prohorov theorem and Jakubowski-Skorokhod theorem enables us to show that the sequence of approximate solutions converges to a global martingale weak solution. In addition, when χ (⋅) ≡ const. > 0 , we prove that the solution is pathwise unique, and hence by the Yamada-Wantanabe theorem that the KS-SNS system admits a unique global pathwise weak solution. [ABSTRACT FROM AUTHOR]

Compositional screening is an important strategy to improve the oxidation resistance of high‐entropy diborides (HEB2), yet the related studies are limited. Here, we report a rare‐earth (RE) element compositional screening strategy to improve the oxidation resistance of HEB2. To be specific, the single‐phase (Hf0.28Zr0.28Ta0.28RE0.16)B2 (HEB2‐RE) samples with 12 different RE elements are fabricated via ultrafast ultrahigh‐temperature synthesis and spark plasma sintering techniques, and their oxidation resistance is explored by isothermal oxidation tests. The results show that the as‐obtained HEB2‐Sc samples possess the best oxidation resistance among all the as‐fabricated HEB2‐RE samples. Such outstanding oxidation resistance is ascribed to the enhanced viscosity of the generated B2O3 glass originating from the solid solution of (Zr, Me)0.84Sc0.16O2 complex oxides, as confirmed by transmission electron microscope observations and first‐principles calculations. [ABSTRACT FROM AUTHOR]

This work is devoted to a study of a compressible generic two-fluid model with possibly unequal velocities for arbitrarily large initial data. This model can describe some interesting physical phenomena, such as counter-current flow in which two fluids move in opposite direction. Less is known about the global existence and uniqueness of large solutions. Even for the one-fluid model, it is still open when the adiabatic parameter belongs to $ (1, \frac{3}{2}] $. The degeneracy of viscosities and the non-conservative form of the pressure terms due to unequal velocities are the main issues. In this work, we obtain the global existence and uniqueness of the solution for arbitrarily large initial data via applying the two-fluid effective velocities to a decomposition of implicit pressure functions and deriving a series of new global a priori $ L^p $ estimates of both velocities and effective velocities. The adiabatic parameters are allowed to be bigger than 1. [ABSTRACT FROM AUTHOR]

This paper proposes a rate-dependent cohesive zone model for simulating the evolution and growth of cracks under dynamic loading. This model takes into consideration the effects of cohesive separation rate and crack growth speed on the cohesive traction-separation relationship to reflect the rate-dependent characteristics of both material viscosity and energy dissipation of micro-crack branches. The evolution algorithm of the cohesive law is presented, wherein separation rate and crack growth speed are evaluated using the backward difference method explicitly in incremental computation, leading to the determination of rate-dependent critical traction and fracture toughness. The proposed model was implemented in ABAQUS software via UEL subroutine and utilized in an example of interfacial crack growth simulation, with satisfactory agreement found among the present results, experimental data, and numerical results from the literature. The effectiveness of the rate-dependent model and numerical algorithm in simulating high speed crack growth is validated through further numerical tests. [ABSTRACT FROM AUTHOR]

The waxy crude oil was routinely transported by means of adding pour point depressants (PPD), which can significantly improve the flow behavior of waxy crude oil. In this study, the physical properties of crude oil were first characterized. Subsequently, a novel variety of W/O nanoemulsion was prepared based on water in an EVA/toluene solution at a 3:1 proportion, and evaluated as a viscosity improver. It was found by virtue of the laser particle size analyzer that the EVA emulsion reaches the nano-scale. EVA nanoemulsion can present a behavior similar to nanocomposite PPD, and form a denser and regular structure with wax crystals via heterogeneous nucleation. Compared with conventional EVA, EVA nanoemulsion further reduces the oil viscosity, gel point and yield value by 52.8%, 0.05 °C and 29.6%. In addition, the impact of particle size of EVA nanoemulsion on the rheology of crude oil was discussed. In combination with DSC curve and POM, the action mechanism of EVA nanoemulsion on crude oil was analyzed. [ABSTRACT FROM AUTHOR]

Studies of intermolecular interactions in butyl acetate-dibutyl phthalate and butyl acetate-dioctyl phthalate systems show that except for excess volume, deviations of properties from an ideal mixture are reduced as the temperature rises. Results indicate considerable van der Waals forces and confirm the effect the size of molecules has on the properties of binary mixtures. Experimental data on density, refractive index, viscosity, excess molar volume, and other properties are presented for systems and pure substances. [ABSTRACT FROM AUTHOR]

Twenty types of polyethylene (PE) including high density polyethylene (HDPE) and linear low‐density polyethylene (LLDPE) with various viscosity were used to study the in‐situ formation of PE‐ ethylene propylene rubber (EPR) core‐shell rubber particles (CSRP) in polypropylene (PP) matrix by melt blending. The results show that PE and EPR cannot form CSRP if PE melt flow index (MFI) is lower than about 0.3 g/10 min. As a result, the impact fracture of PP/PE/EPR composite is brittle. If PE MFI is higher than 0.3 g/10 min, PE and EPR can form CSRP, leading to the ductile impact fracture of PP/PE/EPR composite. Interestingly, upper limit content of PE for the formation of CSRP depends on the type and viscosity of PE. For HDPE, upper limit content of PE tends to increase with the increase of its MFI, whereas it drops considerably for LLDPE. Understanding these relationships provides insights into optimizing the selection of core types and viscosity for enhancing the mechanical properties of polymer composites with core‐shell structure. This may potentially guide the development of cost‐effective and high‐performance polymer composites. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of the vanishing shear viscosity limit and strong boundary layer problem for the compressible, viscous, and heat-conducting planar MHD equations. The main aim is to obtain a sharp convergence rate which is usually connected to the boundary layer thickness. However, The convergence rate would be possibly slowed down due to the presence of the strong boundary layer effect and the interactions among the magnetic field, temperature, and fluids through not only the velocity equations but also the strongly nonlinear terms in the temperature equation. Our main strategy is to construct some new functions via asymptotic matching method which can cancel some quantities decaying in a lower speed. It leads to a sharp L ∞ convergence rate as the shear viscosity vanishes for global-in-time solution with arbitrarily large initial data. [ABSTRACT FROM AUTHOR]

In this paper, we consider the homogenization of evolutionary incompressible purely viscous non-Newtonian flows of Carreau-Yasuda type in porous media with small perforation parameter 0 < ε ≪ 1 , where the small holes are periodically distributed. Darcy's law is recovered in the homogenization limit. Applying Poincaré type inequality in porous media allows us to derive the uniform estimates on the velocity field, the gradient of which is small of size ε in L 2 space. This indicates the nonlinear part in the viscosity coefficient does not contribute in the limit and a linear model (Darcy's law) is obtained. The estimates of the pressure rely on a proper extension from the perforated domain to the homogeneous non-perforated domain. By integrating the equations in time variable such that each term in the resulting equations has certain continuity in time, we can establish the extension of the pressure by applying the dual formula with the restriction operator. [ABSTRACT FROM AUTHOR]

A general formalism is proposed, based on the definition of a space-time potential, for developing space-time formulations adapted to nonlinear and time dependent behaviors. The focus is given to the case of standard generalized materials that are expressed from the knowledge of two potentials, a strain energy and a dissipation potential in a convex framework with the help of internal variables. Viscoplasticity with isotropic hardening and nonlinear finite viscoelasticity are investigated. Starting from the definition of an appropriate space-time potential, time discontinuous Galerkin forms are developed for use in the case of time singularities (in particular with regard to time integration of internal variables). Furthermore, NURBS approximation are used, such as to propose Space-Time Isogeometric Analysis models. Numerical examples allow to compare the obtained isogeometric space-time models with standard finite-element models (that are based on standard time integration procedures: radial return for viscoplasticity and backward euler for viscosity) and allow to illustrate the new possibilities offered with the proposed space-time formulations. [ABSTRACT FROM AUTHOR]

• High pressure density and viscosity of R515B were measured using vibrating-wire viscosimeter in the temperature of 253 K to 363 K when pressure changes from 1 MPa to 12 MPa. • By incorporating the parameterization method of thermodynamic equation of state and the modified residual entropy scaling model from our previous work, a predictive viscosity model for azeotropic refrigerants, considered as pseudo-pure fluids, was proposed. • The variation rule of the viscosity property can be described accurately and reasonably.Please check, thank you in advance. One essential aspect of the studies on the refrigeration and heat pump technology is to search for new alternative working fluids. Meanwhile, the azeotropic mixtures of hydrofluorocarbons (HFCs)/hydrofluoroolefins (HFOs) have attracted researchers not only in fundamentals research field but also in the industry fields due to its good performance and applicability. Therefore, to promote application research, this study is focused on the characteristics of viscosity for azeotrope R515B, which is widely recognized and studied from the thermodynamic aspect. Hence, the high-pressure density and viscosity in liquid phase of R515B were measured with a vibrating-wire viscosimeter within the temperature range in 253 K to 363 K when pressure changes from 1 MPa to 12 MPa. The combined expended uncertainties with a confidence level of 0.95 (k = 2) of density and viscosity are 0.2 % and 2 %, respectively. In addition, a modified viscosity model is proposed with combining the parameterization method of thermodynamic equation of state (EoS) in previous work and the modified entropy variable as well as reduced viscosity reference term of residual entropy scaling (RES) theory. Furthermore, the systematical comparison results among this model and three benchmark viscosity models available illustrate that the RES model proposed in this research is robust and precise in a wide range of operation condition. [ABSTRACT FROM AUTHOR]

Lung alveoli are modeled as spherical caps, lined internally by a thin surfactant-laden liquid film, and the periodic wall shear stress exerted along the epithelium during small-amplitude radial oscillations of their wall is computed. A novel set of boundary conditions, applied at the rim, reveals the dominant role of Marangoni stresses. These stresses develop along the air/liquid interface due to spatial gradients of interfacial surfactant concentration and are transported to the wall by the action of viscosity. The effect of a variety of geometric and functional characteristics, including rim interstitial thickness, alveolar opening angle and liquid film thickness and viscosity, is interrogated, and the results are discussed in relation to the onset and evolution of acute and chronic lung diseases, such as asthmatic attacks, pulmonary emphysema and pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Dielectric oil has been recently used in wire electrical discharge machining (wire EDM) for achieving high-precision machining. However, the influence of dielectric oil properties on wire EDM characteristics has not been clarified sufficiently. This study fundamentally investigated the influence of dielectric oil viscosity on wire EDM characteristics. In this study, three types of dielectric oil differing only in viscosity were prepared and examined. Linear cutting experiment results showed that the removal rate and the machined surface roughness increase with dielectric oil viscosity. Then, the influence of viscosity on crater removal volume was investigated to discuss the cause of the change in removal rate, and it was found that crater removal volume increases with the viscosity. Furthermore, CFD (computational fluid dynamics) analysis results and discharge observation results showed that the debris exclusion becomes worse in higher viscosity oil, and the discharge concentration occurs frequently, resulting in the deterioration in machined surface roughness. Next, the difference in machining accuracy with dielectric oil viscosity was investigated. It was found that the corner shape accuracy deteriorates with the increase of viscosity while the machined surface waviness and straightness improve slightly. Structural analysis results showed that wire deflection increases with viscosity, resulting in the deterioration in corner shape accuracy. On the other hand, high-speed observation of wire vibration was carried out, and it was found that the wire vibration decreases in the case of higher viscosity, which leads to the improvement in machined surface waviness and straightness. [ABSTRACT FROM AUTHOR]

The density and viscosity of the pseudo-binary mixtures of eutectic solvent (ES) composed of choline chloride and ethylene glycol ([ChCl/EG]) with dimethylsulfoxide (DMSO) were measured. In order to understand the effect of the mole ratio of ChCl:EG, two ChCl/EG ESs with the mole ratio of 1:3 and 1:4 (abbreviated as [ChCl/EG](1:3) and [ChCl/EG](1:4) in this work) were prepared. The measurements were carried out by digital vibrating U-tube density meter and Ubbelohde capillary viscometer from 303.15 to 323.15 K at atmospheric pressure (98.5 kPa). The Jouyban–Acree model was applied to correlate the experimental density and viscosity data of DMSO/[ChCl/EG](1:3) and DMSO/[ChCl/EG](1:4) mixtures. In addition, based on the experimental data, the derived properties of the mixtures, such as excess molar volume and viscosity deviation, were calculated. The comparison and analysis of excess molar volume and viscosity deviation for DMSO/[ChCl/EG](1:2) reported in literature and the results obtained in this work were carried out. [ABSTRACT FROM AUTHOR]

The viscosities of the quinary system NaCl + KCl + CaCl2 + MgCl2 + H2O and its binary subsystems are measured in the temperature range of 288.15 K-308.15 K. The viscosities of binary solutions of MgCl2, NaCl, and CaCl2 increase with the increase in concentration. In contrast, for the binary solution of KCl, the viscosity decreases with increasing concentration at low temperature and low concentration. The extended Jones–Dole model that incorporates higher-order term parameters is used to fit the viscosity of binary solutions, with a maximum Average Relative Deviation (ARD) of 1.42%. By comparing the values of the Pearson correlation coefficients, it is found that MgCl2 has the most significant impact on the viscosity of the quinary system MgCl2 + KCl + NaCl + CaCl2 + H2O, while the impact of KCl is the least. The modified extended Jones–Dole model, with the introduction of parameter Gi, can accurately predict the quinary system, resulting in a maximum AAD value of 0.63%. Moreover, the Hu model is also applied to predict the viscosity of the quinary system, achieving a maximum ARD value being 1.54%. Compared to the Hu model, the modified extended Jones–Dole model performs better. The viscosity calculation models for the quinary system MgCl2 + KCl + NaCl + CaCl2 + H2O in this study contribute key parameters for the design and optimization of the potassium chloride production process. [ABSTRACT FROM AUTHOR]

A new approach to defining the effective fracture toughness for heterogeneous materials is proposed. This temporal averaging approach is process dependent, incorporating the crack velocity and material toughness. The effectiveness of the new technique is investigated in the context of hydraulic fracture through heterogeneous rock with a periodic material toughness. The plane strain model is considered without fluid leak-off, to more easily investigate different regimes (toughness/viscosity). Numerical simulations are used to examine the effectiveness of the new homogenisation strategy, with comparison against the recently proposed maximum toughness strategy. Simulations are conducted using an extremely effective (in house-built) time–space adaptive solver. The regimes in which each strategy is effective are determined. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the inviscid limit ν → 0 for time-quasi-periodic solutions of the incompressible Navier–Stokes equations on the two-dimensional torus T 2 , with a small time-quasi-periodic external force. More precisely, we construct solutions of the forced Navier–Stokes equation, bifurcating from a given time quasi-periodic solution of the incompressible Euler equations and admitting vanishing viscosity limit to the latter, uniformly for all times and independently of the size of the external perturbation. Our proof is based on the construction of an approximate solution, up to an error of order O (ν 2) and on a fixed point argument starting with this new approximate solution. A fundamental step is to prove the invertibility of the linearized Navier–Stokes operator at a quasi-periodic solution of the Euler equation, with smallness conditions and estimates which are uniform with respect to the viscosity parameter. To the best of our knowledge, this is the first positive result for the inviscid limit problem that is global and uniform in time and it is the first KAM result in the framework of the singular limit problems. [ABSTRACT FROM AUTHOR]

Based on the PREM Earth model, more than a thousand models of the internal structure of Venus have been built, differing in the radius and density of the core, the density of the mantle, the viscosity distribution and rheology. The core radius varies from 2800 to 3600 km, and the density in the mantle and core varies within a few percent of the PREM model values. When calculating tidal Love numbers, Andrade rheology is used to take into account the inelasticity of the mantle. Specifically the values of the Andrade rheological model parameters that best describe the tidal deformation of the Earth are used. This significantly reduces the error when calculating Love numbers. It has been shown that Venus can have an internal solid core only if the composition of the planet is very different from that of Earth. Comparison of the observed values of the moment of inertia and tidal Love number k2 with model values allowed us to conclude that the radius of the core of Venus is with a high probability in the range of 3288 ± 167 km. [ABSTRACT FROM AUTHOR]

The results of numerical modeling of the values of the Chandler wobble period of Mars have been presented for a set of internal structure models that satisfy all currently available observable data: geodetic (average radius, mass, moment of inertia, tidal Love number k2) and crustal thickness and core radius values obtained from seismic data processing. Andrade rheology was used to take into account inelasticity when calculating model values of the tidal Love number k2 and the Chandler wobble period. It has been shown how the model values of the Love number k2 and the Chandler period depend on the Andrade rheological parameter and the adopted viscosity distribution. [ABSTRACT FROM AUTHOR]

This work is devoted to the large-scale rheology of suspensions of non-Brownian inertialess rigid particles, possibly self-propelling, suspended in a Stokes flow. Starting from a hydrodynamic model, we derive a semi-dilute mean-field description in form of a Doi-type model, which is given by a 'macroscopic' effective Stokes equation coupled with a 'microscopic' Vlasov equation for the statistical distribution of particle positions and orientations. This accounts for some non-Newtonian effects since the viscosity in the effective Stokes equation depends on the local distribution of particle orientations via Einstein's formula. The main difficulty is the detailed analysis of multibody hydrodynamic interactions between the particles, which we perform by means of a cluster expansion combined with a multipole expansion in a suitable dilute regime. [ABSTRACT FROM AUTHOR]

In this paper we present a numerical scheme based on spectral collocation methods to investigate the flow of a piezo-viscous fluid, i.e., a fluid in which the rheological parameters depend on the pressure. In particular, we consider an incompressible Navier–Stokes fluid with pressure dependent viscosity flowing in: (i) a two-dimensional non-symmetric planar channel; (ii) a three-dimensional axisymmetric non-straight conduit. For both cases we impose the Navier slip boundary conditions that can be reduced to the classical no-slip condition for a proper choice of the slip parameter. We assume that the dependence of the viscosity on the pressure is of exponential type (Barus law), even though the model can be replaced by any other viscosity function. We write the mathematical problem (stress based formulation) and discretize the governing equations through a spectral collocation scheme. The advantage of this numerical procedure, which to the authors' knowledge has never been used before for this class of fluids, lies in in the ease of implementation and in the accuracy of the solution. To validate our model we compare the numerical solution with the one that can be obtained in the case of small aspect ratio, i.e., the leading order lubrication solution. We perform some numerical simulation to investigate the effects of the pressure-dependent viscosity on the flow. We consider different wall functions to gain insight also on the role played by the channel/duct geometry. In both cases (i), (ii) we find that the increase of the coefficient appearing in the viscosity function results in a global reduction of the flow, as physically expected. [ABSTRACT FROM AUTHOR]

The effect of temperature (15, 20, 25, 30, and 35 °C) on the ultrasonic degradation of sodium poly(styrene sulfonate) polyelectrolyte (5.10−3 g/ml) in aqueous NaCl solutions (2.75 m) was investigated. Using the thousands of data obtained by an online viscometer monitoring technique, the degradation kinetics, and the effect of temperature on this process were analyzed in detail with 12 theoretical models reported in the literature. The Giz, OHM, and Tang-Goto models were found to give good results, and these models were selected to evaluate the effect of temperature on the ultrasonic polymer degradation. The degradation constant and the limiting molecular weight at which no polymer chain scission occurs were found to decrease with increasing temperature for all models. Furthermore, modeling was performed using popular machine learning algorithms, such as Multilayer Perceptron, Adaptive Neuro-Fuzzy Inference System, Long Short-Term Memory, Gradient Boosting Regression, Light Gradient Boosting Machine, eXtreme Gradient Boosting Regressor, CatBoost, and Random Forest. The best results were obtained with the Long Short-Term Memory, a deep learning approach. In addition, optimization techniques, such as Particle Swarm Optimization, Genetic Algorithm, Artificial Bee Colony, Clustering, and Global Optimization Method based on a parabolic approach, were used to determine the optimum molecular weight evolution and degradation temperature. [ABSTRACT FROM AUTHOR]

Slow release of emerging contaminants limits their accessibility from soil to pore water, constraining the treatment efficiency of physio-chemical treatment sites. DC fields mobilize organic contaminants and influence their interactions with geo-matrices such as zeolites. Poor knowledge, however, exists on the joint application of heating and electrokinetic approaches on perfluorooctanoic acid (PFOA) transport in porous media. Here, we investigated electrokinetic PFOA transport in zeolite-filled percolation columns at varying temperatures. Variations of pseudo-second-order kinetic constants (k PSO) were correlated to the liquid viscosity variations (η) and elctroosmotic flow velocities (v EOF). Applying DC fields and elevated temperature significantly (>37%) decreased PFOA sorption to zeolite. A good correlation between η, v EOF , and k PSO was found and used to develop an approach interlinking the three parameters to predict the joint effects of DC fields and temperature on PFOA sorption kinetics. These findings may give rise to future applications for better tailoring PFOA transport in environmental biotechnology. [Display omitted] [ABSTRACT FROM AUTHOR]

Incorporating an evidence-based approach in STEM education using data collection and analysis strategies when learning about science concepts enhances primary students' discipline knowledge and cognitive development. This paper reports on learning activities that use the nature of viscosity and the power of informal statistical inference to build students' conceptual understanding of interpolation and extrapolation without imposing on them the demands of understanding the nonlinear mathematics used to explore the concepts at the tertiary level. An exploratory research strategy was adopted to investigate the way in which Year 5 students created and analysed graphical representations from data collected when performing viscosity experiments. The data representations produced by the students and their subsequent predictions were analysed using the Structure of Observed Learning Outcomes (SOLO) model as adapted specifically for graphical representations. The results illustrate that when provided with appropriate technological tools to scaffold student learning, in this case TinkerPlots™, development of students' appreciation of interpolation and extrapolation within meaningful data contexts across the STEM curriculum does not have to wait until the tertiary level. [ABSTRACT FROM AUTHOR]

This investigation focuses on the impact of liquid properties--viscosity, surface tension--and air pressure on the Sauter Mean Diameter (SMD) of atomization sprays. Utilizing a twin-fluid atomizer, the study resulted in derived equations that quantify these effects across a spectrum of liquid behaviours, with an emphasis on both viscous and non-viscous liquids. The derivation process for viscous liquids yielded equations showcasing an average deviation of 1.32% from experimentally observed SMD values, validated across a dataset of 250 experimental trials. These trials involved a total of 18,000 droplets analysed, with a standard error of 0.02%, spanning a liquid viscosity range of 3x10-3 to 20x10-3 kg/(m.s), and air pressures from 50 to 300 kPag. For non-viscous liquids, defined by a liquid viscosity threshold of < 3x10-3 kg/(m.s), the equations revealed a higher average deviation of 1.51% from the experimental SMD. These runs included the analysis of 19,600 droplets across liquid surface tensions from 20x10-3 N/m to 72.8x10-3 N/m, with a standard error of 0.03%. This distinction highlights the significant influence of surface tension in shaping the atomization outcomes for these liquids. A quantitative discovery of this research is how a 10% increase in viscosity for viscous liquids correlates to a substantial 33% increase in SMD, impacting around 10,500 droplets per viscosity level, with an observed standard deviation of 0.15% across viscosity measurements. This emphasizes the dominance of viscosity in influencing atomization dynamics for viscous liquids. Conversely, for non-viscous liquids, a 10% increase in surface tension translates to a 45% increase in SMD, affecting approximately 11,200 droplets per surface tension category, with a standard deviation of 0.18% in surface tension measurements. Moreover, this study pioneers the introduction of a particle tracking code, designed for high-speed camera frames, enabling the analysis of over 10,000 droplets per experimental run, summing up to more than 280,000 droplets analysed across all trials, with an overall precision rate of 99.5%. This novel technique enhances system performance by providing highly accurate and real-time droplet size distribution data, which is critical for optimizing atomization processes in industrial applications. In comparison with state-of-the-art studies, this research offers a comprehensive analysis of the combined effects of viscosity, surface tension, and air pressure on SMD, providing new insights and validated predictive models. The contributions of this work lie in its detailed quantitative results and the introduction of advanced measurement techniques, which together represent a significant advancement in the field of atomization. [ABSTRACT FROM AUTHOR]

This study utilized a highly food-compatible heating technique to encapsulate iron within a niosomal structure. The characteristics of niosomal solution of ferrous sulfate, including encapsulation efficiency (EE), loading capacity, particle size, polydispersity index (PDI), zeta potential, bioavailability, and viscosity were measured with meticulous attention to detail. The storage stability, in vitro release of iron, and the morphology of the optimum sample were assessed with the same level of precision. The characteristics of freeze-dried niosomes containing iron, including FTIR, XRD, and DSC, were also evaluated. The optimum sample, a combination of Span 60 and Tween 60 without cholesterol, possessed a particle size of 147 nm, PDI = 0.31, zeta potential = − 27.4 mV, and viscosity = 1 mPa.s. The EE values of different iron-loaded niosomes were around 25%. However, the EE of various samples was successfully enhanced to an impressive 83% after double encapsulation in nanofibers. The findings of this research open a new horizon to future attempts to increase the EE value of niosomal system. [ABSTRACT FROM AUTHOR]

The synovial fluid is responsible for adequately lubricating, moisturizing, and nutritional human joints. This liquid should have appropriate viscoelastic properties and ensure a low coefficient of friction in biotribological systems. Many artificial synovial fluid preparations used in viscosupplementation treatments are based on hyaluronic acid. This work aimed to evaluate the influence of molecular weight on the functional properties of solutions based on hyaluronic acid. 1% solutions based on hyaluronic acid with five different molecular weights from 50,000 Da to 2 MDa were made. Rheological (viscosity, viscoelasticity), tribological (coefficient of friction, wear assessment), and wettability tests were carried out. Significant differences were observed in the rheological tests, where the viscosity strictly depends on the molecular weight of the hyaluronic acid. It has been shown that the molecular weight of HA has little effect on the coefficient of friction. On the other hand, the differences in the tribological wear are much more significant. The molecular weight of biopolymers is one of the essential parameters in developing new artificial synovial fluids. Using a higher molecular weight of hyaluronic acid increases viscosity and wettability, resulting in less tribological wear. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: We propose an implicit discontinuous Galerkin (DG) discretization for incompressible two‐phase flows using an artificial compressibility formulation. The conservative level set (CLS) method is employed in combination with a reinitialization procedure to capture the moving interface. A projection method based on the L‐stable TR‐BDF2 method is adopted for the time discretization of the Navier‐Stokes equations and of the level set method. Adaptive mesh refinement (AMR) is employed to enhance the resolution in correspondence of the interface between the two fluids. The effectiveness of the proposed approach is shown in a number of classical benchmarks. A specific analysis on the influence of different choices of the mixture viscosity is also carried out. [ABSTRACT FROM AUTHOR]

Magnetic viscosity experiments have been performed in order to investigate the magnetization reversal in Sr nanoferrite particles (nanoscale SrFe12O19) and interacting Sr/Co nanoferrite particles (SrFe12O19–CoFe2O4 nanocomposites). The magnetic viscosity S = d M (t) / d l n (t) , where M (t) is the magnetization as a function of time, has been collected. For Sr nanoferrite S shows a maximum close to the coercive field, reflecting the relation between S and the energy barrier distribution. We evidence that magnetic viscosity experiments on Sr nanoferrite and interacting Sr/Co nanoferrite particles provide reliable qualitative results for the different magnetic field sweep rate and saturating field H s a t considered. In addition, the activation volumes extracted from the magnetic viscosity experiments performed at different temperatures on Sr nanoferrite are quantitatively correlated to anisotropy changes. [ABSTRACT FROM AUTHOR]

The response of Newtonian liquids to small perturbations is usually considered to be fully described by homogeneous transport coefficients like shear and dilatational viscosity. However, the presence of strong density gradients at the liquid/vapor boundary of fluids hints at the possible existence of an inhomogeneous viscosity. Here, we show that a surface viscosity emerges from the collective dynamics of interfacial layers in molecular simulations of simple liquids. We estimate the surface viscosity to be 8–16 times smaller than that of the bulk fluid at the thermodynamic point considered. This result can have important implications for reactions at liquid surfaces in atmospheric chemistry and catalysis. [ABSTRACT FROM AUTHOR]

To date, no consensus exists regarding the management of enamel infractions (cracks and craze lines), which may be associated with sensitivity. Two clinical cases are presented on the management of enamel infractions using a modified erosion-infiltration protocol for resin infiltration. Initially indicated for the treatment of early caries lesions, Icon (DMG) low-viscosity resin infiltrant has also been used to mask unesthetic developmental defects of enamel in anterior teeth. Treatment using this modified infiltration protocol immediately eliminated tooth sensitivity associated with the enamel infractions. Resin infiltration has the potential as a minimally invasive and effective treatment for the management of sensitivity associated with enamel infractions. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the clinical performance of two methacrylate-based flowable composites and an ormocer-based flowable composite in noncarious cervical lesions (NCCLs) in adult participants. Method and materials: In total, 183 restorations were performed on NCCLs. All cavities were restored using a universal adhesive system (Futurabond U, Voco) with selective enamel etching and with one of the three evaluated flowable composites (n = 61): low-viscosity methacrylate-based composite (GrandioSO Flow, LV), high-viscosity methacrylate-based composite (GrandioSO Heavy Flow, HV), and an ormocer-based flowable composite (Admira Fusion Flow, ORM). All restorations were evaluated using FDI and USPHS criteria after 24 months. Kruskall-Wallis analysis of variance rank (α = .05) was used for statistical analysis. Results: After 24 months of clinical evaluation, 16 restorations were lost (LV = 3, HV = 10, ORM = 3) and the retention rates (95% confidence interval) were 95.0% for LV, 82.2% for HV, and 95.0% for ORM, with statistical differences observed between HV and LV as well as HV and ORM (P < .05). When secondary parameters were evaluated, no significant differences between groups were observed (P > .05). Thirty-three restorations (LV = 8, HV = 13, ORM = 12) showed minor marginal staining, 71 restorations (LV = 26, HV = 20, ORM = 25) presented small marginal adaptation defects, and one restoration for HV presented recurrence of caries. Conclusion: The universal adhesive associated with the ormocer-based and methacrylate-based flowable composite showed promising clinical performance after 24 months. However, the heavy-flow restorations showed significantly more failures. [ABSTRACT FROM AUTHOR]

The viscosity of high entropy alloys in liquid atomization process has the important influence on the atomization effect. Using the existing ternary alloy viscosity model, a new viscosity model of the CoCrFeMnNi high-entropy alloy melt with equal molar ratio was established through the model expansion in this paper. The influence of temperature on the viscosity of five-element high entropy alloys was studied. The viscosity curves were drawn and modified, and the relationship between temperature and viscosity of high entropy alloys was calculated. In the results, the viscosity decreases from 0.0211 Pa·s to 0.0114 Pa·s when the temperature increases from 1360 K to 2000 K. With the increase of the element content, the viscosity of high entropy alloys increases. Cr has the most significant effect on the alloy viscosity, while Fe and Co have the same effect on the viscosity. The prediction model results of liquid viscosity for five-element high entropy alloys are consistent with the experimental results of thermal state experiment.

This work presents the study of the rheology ical behavior of Algerian kaolin (DD1) suspensions considering two types of electro-steric dispersants (Hypermer KD1 and Darvan 7) and the evaluation of their effectiveness at neutral pH. The results showed that Darvan 7 exhibits electro-steric behavior at neutral pH, whereas KD1 exhibits purely steric behavior. The addition of a dispersant strongly influenced the rheological behavior of kaolin suspensions. The DD1 suspensions without dispersant exhibited fluidifying plastic behavior (Casson model). The shear stresses decreased significantly with the addition of dispersant, while the significant decrease in viscosity indicated that the dispersant reduced the strength of the particle networks that make up the slurry. The suspensions with 1 wt.% dispersant were consistent with the Bingham model, with a very low yield point. The viscosity of the dispersion reached a minimum when the concentration of the dispersant was 1 wt.%. This value was lower with Darvan 7. The addition of aluminum slag as a source of alumina to KD1 increased its efficiency and lowered the viscosity of the kaolin suspensions.

Abstract The study was conducted on the impact of thermophysical properties on eflornithine drug solute–solvent interactions in aqueous ethyl acetate and acetone at different concentrations and temperatures. The aim of this study is to enhance the understanding of eflornithine’s behavior in different solvents, which is crucial for its effective use in pharmaceutical applications. The density, molar volume, viscometric, and conductometric characteristics of the eflornithine drug solutions (0.025, 0.05, 0.075, 0.1, and 0.125 mol/kg) in acetone and 25% (v/v) aqueous ethyl acetate were measured within a temperature range of 298.15 K–318.15 K. Based on the determined density parameters, the following parameters were assessed: viscosity (η), equivalent molar conductance, limiting apparent molar volume (V0φ), apparent molar volume of transfer (V0φtr), and apparent molar volume (Vφ). The Masson empirical relationship and the viscosity-to-Jones-Dole (JD) equation were used to evaluate the partial molar volume (Vφ), experimental slope (SV), viscosity, and density data. Temperature and concentration were used to determine each parameter. For each set of dilutions, conductometric studies were conducted in both study solvents. The gathered data was analyzed in order to evaluate the ion–solvent interactions. The Walden product Λo mηo’s positive temperature coefficient values indicate that the drug eflornithine functions as a structural modifier in acetone and aqueous acetyl acetate systems. The structure-making and breaking characteristics of the polar solvents acetone and ethyl acetate were identified.

Protein concentrates have a high biological value and contain significantly less lactose in comparison with dry skimmed milk. The use of protein concentrates in ice cream without the content of non-fat milk solids allows not only making up for protein but also developing the component composition of a product with the low content of lactose. In this regard, the study of technologically significant quality indicators of ice cream with the low content of lactose without non-fat milk solids when using milk and whey protein concentrates is an urgent task. The rheological, microstructural, color and thermostatic characteristics, as well as the oxidative stability of fat of the test samples were determined in the research. It has been found that viscosity decreased by 1.8-2.6 times when using whey proteins. The use of protein concentrates led to an increase in hardness and adhesiveness by 2.2-4.1 and 1.6-5.0 times, respectively, but did not significantly affect the thermal stability. The mass fraction of fat had the greatest influence on these characteristics. The study of color characteristics of ice cream made it possible to reveal a decrease in the yellowness index when using milk protein concentrate. It has been established that color differences in most of the samples were not recognizable to the human eye. The induction period was characterized by the lowest value in the samples with whey proteins, thus indicating a probability of a faster oxidation process in them. The use of protein concentrates did not have a significant effect on ice crystals. The stability of the air phase was significantly reduced when using the whey proteins. A multivariate analysis of the studied samples divided them into the control and the samples containing protein concentrates. Based on the technologically significant quality indicators, the use of milk protein concentrates in the production of low-lactose ice cream is more preferable than the use of whey protein concentrates.

In this experiment, egg white protein microparticles (EWPM) were used as a lipid substitute matrix to investigate the effects of EWPM/xanthan gum (XG) blend concentration, pH, sodium chloride concentration, sugar concentration, and homogenization conditions on the rheological properties of ultra-low-fat salad dressing products. The results showed that XG had a significant thickening effect on EWPM-based ultra-low-fat salad dressing. However, excess XG led to a decrease in the resilience of low-fat salad dressing. The effects of basic seasoning components on the quality of ultra-low-fat salad dressing were significantly different. pH and salt concentration had a significant impact on the viscosity of the salad dressing system, while sugar addition had a relatively smaller impact on the viscosity. Moderate colloid mill homogenization speed and time reduced the particle size of the product, thereby increasing the internal uniformity and significantly improving the viscosity of ultra-low-fat salad dressing. This study provides a clearer direction for the optimization of low-fat salad dressing.

Background: Finding a new natural scaffold is challenging due to crucial impact on long-term treatment outcomes in pulp capping. In this context, nano hydroxyapatite (nano-HA) is a potential candidate having similar properties to bone tissue in the body. The compound is often synthesized with Epigallocatechin-3-gallate (EGCG) which offers anti-inflammatory and antibacterial properties. Therefore, this study aims to contribute novel insights into the development of effective pulp capping materials by determining the viscosity ratio of the combination of nano-HA and EGCG applied to the cavity according to standard pulp capping material, as well as proving the antibacterial effect against Lactobacillus acidophilus. Methods: The combination of nano-HA – EGCG is divided into three treatment groups, (G1) 1:1 ratio, (G2) 1:1.5 ratio, (G3) 1:2 ratio, as well as control group G4 (Ca(OH)2 and aquadest) with a ratio of 1:1. Meanwhile, each group is tested for viscosity using a Brookfield viscometer. The well diffusion method is used to determine the antibacterial activity by measuring the diameter of the inhibition zone for each treatment, with C1 (Ca(OH)2 and aquadest) as control group at a ratio of 1:1, and three treatment groups (nano-HA – EGCG), (C2) 0.5:1 ratio, (C3) 1:1 ratio, and (C4) 2:1 ratio. Results: The results show that there is a difference in the viscosity of each group with G3 having a viscosity of 12.0183 cP, which is closest to control. Furthermore, significant differences are also reported in antibacterial activity between control and treatment groups. Conclusion: The ratio of 1:2 (G3) has a viscosity that closely matches the standard of pulp capping materials. The combinations of nano-HA and EGCG are proven to have antibacterial power against Lactobacillus acidophilus.

Both starch and dietary fiber, which are important nutrients in cereals, and are beneficial to human health. The digestion rate and digestibility of starch are key factors affecting postprandial blood glucose in the human body. Dietary fiber, that is a nutrient content, has been not easily digested by small intestine, and has the effect of slowing down the digestion of starch, has received much attention in recent years. In this study, the effects of dietary fiber on starch digestibility have been reviewed, and the mechanisms of dietary fiber slowing down starch digestibility from three aspects: reducing amylolysis kinetics, delaying gastric emptying by viscosity of dietary fiber, physical embedding of starch by dietary fiber and wrapping starch with intact cell wall have been summarized, so as to provide a theoretical basis for the subsequent design and production of low glycemic index (GI) foods.

The research aims to determine the quality of cooking oil based on the viscosity coefficient using an Arduino UNO-based viscosity coefficient determining tool. By integrating the Arduino UNO into the viscosity measurement process, this research shows innovation in adapting widely available technology for scientific purposes. The series of tools for determining the value of the viscosity coefficient work if an iron ball enters the fluid and will be detected by magnetic sensors 1 and 2 if it passes through the sensor, which is placed at a predetermined distance. Research was conducted to test the quality of cooking oil by determining the viscosity coefficient. The method research is analyzing recorded videos of the motion of objects falling in oil with Tracker Software. By tracking the video recording of the motion of an object falling in a liquid, data, and graphs of the speed of the falling motion can be obtained. Then from the data obtained, the viscosity value is obtained using the equation. The results of the 5 cooking oils, using the tool, were that oil 1 had a viscosity coefficient of 0.2732 Pa.s; oil 2 with 0.3077 Pa.s; oil 3 with 0.3127 Pa.s; oil 4 with 0.3186; and oil 5 with 0.3218 Pa.s. Meanwhile, the results of the oil viscosity coefficient using manual calculations showed that oil 1 had 0.2733 Pa.s; oil 2 with 0.3089 Pa.s; oil 3 with 0.3136 Pa.s; oil 4 with 0.3188; and oil 5 with 0.3219 Pa.s. The percentage of error that occurs from the tool is 0.17%. The oil with a smaller viscosity coefficient is coconut oil (better quality than palm oil), while the quality of bulk oil is indicated by a larger viscosity coefficient. It could be asserted that the oil's quality improves as the viscosity coefficient decreases.

Introduction. Currently, the development of composite systems doped with nanoparticles and based on liquid crystal (LC) media is being actively pursued. The latter, having unique properties, can be used to improve various LC devices. For this purpose, it is very important to investigate the mechanism of change in the properties of liquid crystal systems from the size and concentration of nanoparticles. Recently, a sufficient number of methods have been applied to measure the flow of liquid or gas based on different physical principles. Information about the average mass flow rate of a liquid or gas can be obtained by a measurement method based on steady-state heat injection into the flow. The average flow velocity can be measured by electromagnetic and ultrasonic sensors, while the average volume flow rate can be measured by hydrodynamic (aerodynamic) as well as mechanical turbine methods. In heat transfer and mass transfer, convective motion in a fluid medium plays an important role in the vast majority of natural phenomena and technological processes. Many processes of convective mass transfer and heat transfer in chemical, petrochemical, construction, nuclear and other industries are carried out in heat pipes. Up to the present time the question about efficiency of heat pipes application with bodies from composite materials also remains open. In the presented work the following objectives were set: to assemble an experimental setup to study the thermal effect (flow), to conduct studies of temperature change on the surface of the conductor of the compound based on nanoparticles of liquid crystals and viscosity of liquid crystals from the concentration of nanoparticles. Methods and Materials. In this experimental work, a heat flux acts in the region of the outer boundary of the conductor. Note that the redistribution of the thermal field is influenced by such processes as heat conduction and heat transfer. To observe the thermal effect, compounds based on liquid crystal nanoparticles were used. Nanostructured liquid crystal systems have a unique property as fluidity inherent in ordinary liquids. For opaque conductor walls, a method for determining the direction of heat flow is proposed. Earlier experimental studies have shown that temperature measurement is possible only by pyrometric method. Therefore, the redistribution of temperature change on the conductor flow surface was recorded using an optical pyrometer that perceives thermal (infrared) radiation. In this work, a compound based on liquid crystal nanoparticles, namely with the addition of cholesteryloleate, was used as a base. Results and discussion. In the course of the study, temperature dependences in the heat flow zone of the conductor in the absence and in the presence of liquid motion were experimentally obtained. Dependences of temperature change on the surface of the conductor with compounds based on nanoparticles of liquid crystals have been measured. Inhomogeneous redistribution of the thermal field is shown. The results of the study of the dependence of the viscosity of nematic liquid crystals on the concentration of nanoparticles are presented. Conclusion. The above data show that the thermal effect on the surface is not uniformly distributed. For visualization of the thermal effect, compounds based on nanoparticles of liquid crystals turned out to be more effective. A technique has been developed to determine the direction and calculate mathematically the magnitude of the liquid heat flux in the opaque conductor flow. It should be noted that the viscosity of liquid crystals changes when nanoparticles are coupled.

Different types of models are used to study the stress-strain behavior of asphalt concrete mixture during compaction. For modeling it is necessary to know the values of model parameters in the whole range of changes in the characteristics of the compacted material. The aim of the paper is to develop a methodology for determining model parameters based on the results of laboratory creep-recovery testing of asphalt-concrete mixture. In the paper, a model reflecting elastic, visco-elastic and visco-fluid properties of the compacted material is adopted. A differential equation representing the law of behavior of the asphalt-concrete mixture layer under load is obtained. The stages of creep-recovery testing are analytically described, namely: rapid loading with a constant load and deformation under this load; load removal and recovery. Initial conditions for the mentioned stages are determined. Taking into account the initial conditions, analytical expressions of the laws of deformation of the model under the action of a constant load and in the process of recovery are obtained. The methodology of laboratory experiments on creep-recovery is described, according to the results of which the required values of the model parameters with minimum absolute error are obtained. The developed methodology allows to determine the parameters of the model describing the stress-strain behavior of asphalt-concrete mixture of different density and temperature. Consequently, it is possible to simulate the behavior of the asphalt concrete mixture layer at the preliminary, main and final stages of compaction in order to determine the effective operating modes of compaction equipment.

Alkaline–surfactant–polymer (ASP) flooding by means of which alkali additives, surfactant and polymer are inserted as the same slug is one of the most favourable worldwide focuses of Chemical Enhanced Oil Recovery (cEOR) research and field trials, due to the individual synergy of the three chemical components. To develop efficient oil recovery chemicals, it is essential to fully understand the mechanism behind ASP flooding. Nonetheless, there are hardly any studies reporting a systematic characterization of the ASP process. Thus, the present paper focuses on modelling this process in a laboratory by the use of an anionic surfactant—sodium dodecyl sulphate (SDS) in alkaline–polymer media—which is composed of a commercial water-soluble polymer (Flopaam AN125SH®, SNF Floerger, Andrézieux-Bouthéon, France) and alkali compounds (NaOH and Na2CO3). The samples were characterized using rheometry, dynamic light scattering (DLS), infrared spectroscopy (IR) and measurement of inferfacial tension (IFT) between the samples and rapeseed oil. In accordance with the experimental results, surprisingly lower IFT values were recorded between the alkaline–polymer solutions and rapeseed oil than the samples which contained SDS. Increasing polymer and sodium chloride concentration caused a decrease (from 0.591 mN/m to 0.0486 mN/m) in IFT between the surfactant containing samples and rapeseed oil. The IR measurements confirmed that the surfactant was not detected in the oil phase in the absence of NaOH and Na2CO3. The effects of SDS on the viscosity of the mixtures were also investigated, as viscosity is a considerably important parameter in processes using polymers.

In order to obtain coatings with low emissivity, most studies focus on the screening of resin and filler components. However, the influence of process parameters on emissivity during the coating preparation process was rarely studied, and the interaction between various preparation processes was not analyzed. In this study, aluminum powder was selected as the metal filler and fluorocarbon resin was selected as the adhesive to prepare a low-infrared emissivity coating. Initially, single-factor experiments were conducted to regulate the viscosity of the coating(achieved by varying the amount of diluent added to the coating), the wet film thickness of the coating and the curing temperature. The combined effects of these three process parameters on the distribution of aluminum powder in the coating and the infrared emissivity of the coating were analyzed and studied. The response surface methodology was used to further analyze the interactions between the process parameters, and the optimal combination of process parameters were determined to guide the actual coating preparation process. Results showed that the influence of the three process parameters on the emissivity of the coating decreased in the order of coating viscosity > curing temperature > wet film thickness. When the addition amount of diluent was 78 g, the film thickness was 60 μm, and the curing temperature was 73 ℃, the infrared emissivity of the coating was 0.141 in the band of 3～5 μm and 0.177 in the band of 8～12 μm.