Crystal plasticity finite element (CPFEM) modeling of metals that can be age hardened consisting of second phase particles is extensively performed based on representative volume element (RVE) ...models. The RVE model is generated for ferritic low-carbon steel using the data obtained from microstructural observation through optical microscopy (OM) and electron backscatter diffraction (EBSD). The generated RVE is required to statistically represent the original material in terms of grain topology and texture in microscale, as well as the configuration of second phase particles in submicron scale. The multiscale, multi-phase nature of the generated RVE leads to a computationally expensive modeling procedure. To overcome this issue, an alternative multiscale modeling approach based on a homogenization scheme is proposed, in which the effect of second phase particles on deformation behavior is accounted for with no need for the explicit presence of particles in RVE. Lastly, a thorough parametric analysis is performed to investigate the sensitivity of the mechanical properties to the second phase particles in terms of size, volume fraction, geometrical distribution, and deformable or non-deformable properties of precipitates in the investigated material. The results show that the proposed multiscale modeling approach successfully accounts for the effect of second phase particles on deformation behavior, while the computational cost is reduced by more than 99%. In addition, the simulations show that the configuration of second phase particles at a microscale plays an important role in defining the mechanical behavior of the material.
There is an increasing demand for acquiring details of food nutrients especially among those who are sensitive to food intakes and weight changes. To meet this need, we propose a new approach based ...on deep learning that precisely estimates the composition of carbohydrates, proteins, and fats from hyperspectral signals of foods obtained by using low-cost spectrometers. Specifically, we develop a system consisting of multiple deep neural networks for estimating food nutrients followed by detecting and discarding estimation anomalies. Our comprehensive performance evaluation demonstrates that the proposed system can maximize estimation accuracy by automatically identifying wrong estimations. As such, if consolidated with the capability of reinforcement learning, it will likely be positioned as a promising means for personalized healthcare in terms of food safety.
In the present study, the 3-1H-benzo d imidazole-2-yl-quinolin-2-ol (BIMQ) was used as a corrosion inhibitor and its mitigation performance against the corrosion of mild steel (MS) in 1 M HCl and H
2
...SO
4
solution was examined through gravimetric weight loss, potentiodynamic polarization (PDP), and electrochemical impedance studies (EIS). The surface morphology was examined using scanning electron microscopy (SEM), and UV–visible (UV–Vis) spectroscopic studies were carried out to study the electron transfer. Theoretical studies have been implemented using quantum chemical calculations and molecular dynamics simulation. Weight loss studies revealed that the corrosion rates decreased with increasing concentration of BIMQ. Polarization results confirmed that the presence of BIMQ suppressed the metal dissolution and hydrogen evolution at the anodic and cathodic regions in both acidic media. The inhibitor showed 86.0 and 94.2% inhibition efficiency at a 50 ppm concentration of BIMQ. EIS results indicated that the BIMQ reduces the speed of corrosion reaction of MS in 1 M HCl and H
2
SO
4
. Inhibitor adsorption isotherm data revealed that the inhibition process obeys Langmuir isotherm. The UV–Vis absorption spectrum confirmed the electron transfer, and SEM studies showed that the corrosion of MS surface is significantly reduced in the presence of BIMQ. Quantum chemical calculations revealed that the investigated molecule has a widespread electron density and active sites over the entire molecular structure. Molecular dynamics simulation indicated that the molecule stands parallel to the iron surface in close contact to the iron surface.
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•A new hydrazone derivative inhibits steel rebar corrosion in chloride-contaminated SCPS.•The tested inhibitor exhibits an excellent corrosion protection for 720 h of immersion.•XPS ...and other characterization techniques confirm the effective adsorption of inhibitor molecules on steel rebar.•SCC-DFTB simulation reveals the formation of chemical bonds between inhibitor molecules and iron surface.
Corrosion-induced deterioration of infrastructure is a growing global concern. The development and application of corrosion inhibitors are one of the most effective approaches to protect steel rebar from corrosion. Hence, this study focuses on a novel hydrazone derivative, (E)-N′-(4-(dimethylamino)benzylidene)-2-(5-methoxy-2-methyl-1H-indol-3-yl)aceto-hydrazide (HIND), and its potential application to mitigate corrosion in steel rebar exposed to chloride-contaminated concrete pore solutions (ClSCPS).
The research aims to evaluate the anti-corrosion capabilities of HIND on steel rebar within a simulated corrosive environment, focusing on the mechanisms of its inhibitory effect.
The corrosion of steel rebar exposed to the ClSCPS was studied through weight loss and electrochemical methods. The surface morphology of steel rebar surface was characterized by FE-SEM-EDS, AFM; oxidation states of the steel rebar and crystal structures were examined using X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) methods. Further, experimental findings were complemented by theoretical studies using self-consistent-charge density-functional tight-binding (SCC-DFTB) simulations. The performance of HIND was monitored at an optimal concentration over a period of 30 days.
The results indicated a significant reduction in steel rebar corrosion upon introducing HIND. The inhibitor molecules adhered to the steel surface, preventing further deterioration and achieving an inhibition efficiency of 88.4% at 0.5 mmol/L concentration. The surface morphology analysis confirmed the positive effect of HIND on the rebar surface, showing a decrease in the surface roughness of the steel rebar from 183.5 in uninhibited to 50 nm in inhibited solutions. Furthermore, SCC-DFTB simulations revealed the presence of coordination between iron atoms and HIND active sites.
The findings demonstrate the potential of HIND as an effective anti-corrosion agent in chloride-contaminated environments. Its primary adsorption mechanism involves charge transfer from the inhibitor molecules to iron atoms. Therefore, applying HIND could be an effective strategy to address corrosion-related challenges in reinforced infrastructure.
Existing smartphone-based solutions to prevent distracted driving suffer from inadequate system designs that only recognize simple and clean vehicle-boarding actions, thereby failing to meet the ...required level of accuracy in real-life environments. In this paper, exploiting unique sensory features consistently monitored from a broad range of complicated vehicle-boarding actions, we propose a reliable and accurate system based on fuzzy inference to classify the sides of vehicle entrancebyleveragingbuilt-insmartphonesensorsonly. Theresultsofourcomprehensiveevaluation on three vehicle types with four participants demonstrate that the proposed system achieves 91.1%∼94.0% accuracy, outperforming other methods by 26.9%∼38.4% and maintains at least 87.8 %accuracy regardless of smartphone positions and vehicle types.
A constitutive law was developed based on the evolutionary yield function to account for the evolution of anisotropy induced by the plastic deformation. For the effective description of anisotropy, ...the yield stress function and plastic potential were separately defined based on the non-associated flow rule. In particular, for the description of the equivalent status, the accumulated plastic work was employed as an alternative to the accumulated plastic strain. Numerical formulations based on the plastic work were also derived in case the hardening rule, as well as the evolution of the plastic potential and yield stress function, were defined in terms of the plastic work. The developed constitutive law was characterized using the mechanical properties of the multi-phase BAO QP980 steel and niobium sheets at room temperature. From the uniaxial tension tests and the balanced biaxial tension test, separate sets of anisotropic coefficients for each of the plastic potential and yield stress functions were obtained as a function of the plastic work. By comparing with non-evolving yield functions, the importance of the developed constitutive law to properly describe the evolution of the plastic potential and yield function were validated.
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•Bi2O3-B2O3-PbO glasses are examined for γ-, α-, e−, proton, and neutron radiation shielding.•Relevant theoretical and computational approaches are utilized to derive all radiation ...attenuation qualities.•20–1524 keV photon energy range is considered to obtain various γ-ray interaction parameters.•The geometric progression (G–P) fitting method is applied to determine the EBFs and EABFs.•20Bi2O3-20B2O3-60PbO (mol%) glass shows superior γ-ray and fast neutrons attenuation efficacies.
MCNPX, Geant4 and FLUKA codes are employed to compute mass attenuation coefficients (μ/ρ) for 20Bi2O3-(80-x)B2O3-xPbO (x = 0, 20, 30, 40 and 60 mol%) glasses at 20, 30, 40 and 60 KeV, 133Ba (81, 161, 223, 276, 303, 356 and 384 keV), 57Co (122 and 136 KeV), 22Na (511 and 1275 keV),137Cs (662 keV),54Mn (835 keV), 60Co (1173 and 1333 keV) and 42K (1524 keV) photon peaks where 20, 30, 40 and 60 KeV energies are utilized for Mammography, Dental, General and Computed tomography (CT) scanning accordingly, in this study. All simulated μ/ρ outcomes accuracy was verified by WinXCOM and Phy-X/PSD programs’ μ/ρ findings and we noticed a satisfactory agreement among them. From μ/ρ and linear attenuation coefficient (μ) values effective atomic number (Zeff), effective electron density (Neff), half-value layer (HVL), tenth-value layer (TVL) and mean free path (MFP) have been determined. 20Bi2O3-20B2O3-60PbO (mol%) glass HVL and MFP have been compared with some commercial glasses, alloys, polymers, concretes and lead and ceramics corresponding values. Later equivalent atomic numbers (Zeq) and applying geometric progression (G–P) fitting method at 1 – 40 mfp penetration depths (PDs) at 0.015–15 MeV energy range exposure buildup factors (EBFs) and energy absorption buildup factors (EABFs) were estimated. At all selected twenty energies derived radiation protection efficiency (RPE) results confirmed studied samples’ excellent efficacy for low energy photons absorption. Moreover, applying SRIM codes mass stopping powers (MSPs) and projected ranges (PRs) for protons and α-particles and utilizing ESTAR database electron MSPs and continuous slowing down approximation (CSDA) range for electrons were determined at kinetic energy (KE) range of 0.015–15 MeV. Further fast neutron removal cross-sections (ΣR), for 0.0253 eV energy neutrons coherent and incoherent scattering cross-sections (σcs and σics), absorption cross-section (σA) and total cross-section (σT) quantities were evaluated. Derived ΣR was changed at 0.1166–0.123 cm−1 range depending on PbO addition in chosen samples. 20Bi2O3-80B2O3 (mol%) glass has larger σT (23.094 cm−1) in all studied samples for thermal neutron absorption while 20Bi2O3-20B2O3-60PbO (mol%) sample shows superior attenuation factors for photons and fast neutrons signifying included PbO positive effect.
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•• Nuclear radiation shielding aspects and mechanical features are evaluated for ten lithium bismuth borate glasses.•• Pertinent theoretical methods and computational approaches are ...employed to deduce shielding parameters.•• 35B2O3-55Bi2O3-10Li2O (mol%) glass exhibits better gamma-ray attenuation ability.•• 70B2O3-10Bi2O3-20Li2O (mol%) glass shows superior efficacy for thermal neutrons absorption.•• Young's modulus, bulk modulus, shear modulus, longitudinal modulus, and Poisson’s ratio are derived theoretically.
Against photon energies extending from 0.015 to 15 MeV, MCNPX, FLUKA and PHITS codes are operated to simulate mass attenuation coefficients (μ/ρ) for a total of ten B2O3-Bi2O3-Li2O glass compositions with added Bi2O3 amount from 10 to 55 mol% (5 mol% growth gradually) as a substitute for total (B2O3 + Li2O) mol% content. All the computed μ/ρ values correctness is examined by Py-MLBUF and WinXCOM programs’ μ/ρ outcomes and we found a good agreement among them. 55Bi2O3-35B2O3-10Li2O (mol%) glass half-value layer (HVL) and mean free path (MFP) quantities are compared with distinct commercial γ-ray attenuating glasses, alloys, polymers, concretes and lead and ceramics corresponding values. Next, equivalent atomic numbers (Zeq) and by employing geometric progression (G–P) fitting method at 1–40 mfp PDs (penetration depths), at 0.015–15 MeV energy range ‘buildup factors’ were calculated. At all chosen twenty-five energies derived radiation protection efficiency (RPE) results assured investigated samples exemplary competence for low energy photons absorption. Applying SRIM codes ΨP and ΦP and ΨA and ΦA (mass stopping powers (MSPs) and projected ranges (PRs) for protons and α-particles), and making use of ESTAR database ΨE (electron MSP) and continuous slowing‐down approximation (CSDA) range for electrons are determined at KE (kinetic energy) range of 0.015–15 MeV. Moreover, fast neutron removal cross-sections (ΣR), for 0.0253 eV energy neutrons absorption cross-sections have been estimated. Deduced ΣR was altered at 0.1105–0.1205 cm−1 range with Bi2O3 inclusion in studied samples. 10Bi2O3-70B2O3-20Li2O (mol%) glass has greater total cross-section (=23.251 cm−1) for thermal neutrons absorption while 55Bi2O3-35B2O3-10Li2O (mol%) sample exhibits quality shielding factors for photons and fast neutrons confirming the included Bi2O3 positive impact. Along with nuclear attenuation features various physical and mechanical aspects are also inspected. Derived Vm (molar volume), OPD (oxygen packing density), Vo (oxygen molar volume), Vt (packing density) and Gt (dissociation energy per unit volume) values indicated glasses rigidity. Following Makishima–Mackenzie's theoretical model primary mechanical features like Y, K, S and L (Young's, bulk, shear and longitudinal modulus) and σ (Poisson's ratio) are evaluated where 10Bi2O3-70B2O3-20Li2O (mol%) glass shows better elastic moduli in all samples.
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•Nuclear radiation shielding aspects and physical and mechanical features of ternary B2O3-Bi2O3-BaO glasses are explored.•Phy-X/PSD, MCNPX, Geant4, FLUKA, and SRIM codes are used to ...evaluate γ-, α-, proton, and neutron attenuation factors.•25B2O3-70Bi2O3-5BaO (mol%) glass exhibits superior γ-ray and fast neutron attenuation ability.•Different physical characteristics are assessed by employing relevant formulae.•Young's modulus, bulk modulus, shear modulus, longitudinal modulus, and Poisson’s ratio are derived using both Bond compression and Makishima–Mackenzie models.
For B2O3-Bi2O3-BaO glass system, γ, proton, alpha, electron, and neutron radiation shielding aspects were examined. Adopting Phy-X/PSD software, mass attenuation coefficients (μ/ρ) have been derived, and such μ/ρ quantities are in good unanimity with evaluated FLUKA, Geant4, and MCNPX codes corresponding μ/ρ end products. Equivalent atomic number and up to 40 mfp ‘buildup factors’ (utilizing G–P fitting procedure) were reckoned at ten distinct penetration depths. Deduced radiation protection efficiency values validated all glasses’ laudable absorption potential for the minimal energy photons. At 15–15 × 103 KeV kinetic energy range, alpha particle and proton mass stopping powers and projected ranges by SRIM code including electron mass stopping power using ESTAR database were evaluated. For fast neutrons, the calculated macroscopic effective removal cross-section (ΣR) reveals that 25B2O3-70Bi2O3-5BaO (mol%) sample owns proportionately larger ΣR (=0.1206 cm–1). 70B2O3-15Bi2O3-15BaO (mol%) glass exhibits the largest total cross-section for thermal neutron absorption. Further, various physical features and elastic (Young’s, bulk, shear, and longitudinal) moduli and Poisson’s ratio values were derived for all samples. Both BC (bond compression) and M-M (Makishima–Mackenzie) models have been utilized for elastic aspects evaluation, and such features are altered considerably with Bi2O3 increment in the studied glasses. By BC and M-M models, obtained Poisson’s ratio is varied at 0.2434 – 0.2749 and 0.2384 – 0.2826 ranges respectively.
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