Development of Forecasting Model for Prediction of Compressive Strength of Foamed Concrete using Density with W/C ratio and S/C ratio by the Application of ANN

This Artificial neural network study presents the prediction model for a cellular foamed concrete. Foamed Concrete is a cementitious material that should consist of a minimum of 20% of foam, which is mechanically entrained using the mechanical generator of foam. Foamed Concrete possesses a cellular microstructure. By which they become a highly air-entrained system having unusual physical and mechanical properties. It is the perfect mixture of cement, water, sand (fine aggregate), and perforated foam. Published information related to the prediction of foamed concrete is limited, and rational guidelines to evaluate the compressive strength of the concrete are not widely available. This study aims to encourage the strength of foamed concrete economically and predict the strength in the compressive form of concrete. A dataset of 153 instances having an input parameter proportion of Density, W/C ratio, & S/C ratio have been taken to predict compressive strength to elevate and expand the precision and accuracy of the foamed concrete. The data has been trained with the help of ANN, in which we conduct a network analysis to forecast the compound’s performance and stability. The deficiency of strength of foamed concrete is to be sorted out with the help of ANN, and the prominent and reliable equation for the compression power is generated. ANN helps to optimize the compressive strength at the time of physical casting of the concrete.

An Effective Strengthening Strategy of Nano Carbide Precipitation and Cellular Microstructure Refinement in a Superalloy Fabricated by Selective Laser Melting Process

An effective strategy to strengthen a superalloy processed by selective laser melting (SLM) is proposed. The aim is to increase the yield strength of Inconel 718 fabricated by SLM to beyond 1400 MPa, which has never been achieved before. In this study, various NbC additions (0.0%, 0.5%, 1.0%, and 5.0% by weight) were added in the powder bed of Inconel 718, and two types of post-SLM heat treatments were investigated, i.e., solution heat treated plus aging (STA) and direct aging (DA). With NbC addition, smaller depth of melt pool and finer dendritic cells were obtained. Both STA and DA promoted the precipitations of γ’ and γ”. STA eliminated the cellular dendrites and induced grain growth while DA retained the as-built cellular dendrites, grain size, and nano-carbide from NbC addition, rendering a significant 326.2 MPa increase in yield strength. In this work, 0.5% NbC addition exhibited a record-high yield strength of 1461 MPa and ultimate tensile strength of 1575 MPa for Inconel 718 processed by laser manufacturing process according to literature data to-date.

Marine Atmospheric Corrosion of Additively Manufactured Stainless Steels

Additively manufactured (AM) stainless steels exhibit numerous microstructural differences compared to their wrought counterparts, such as Cr enriched dislocation cell structures. The influence these unique features have on a SSs corrosion resistance are still under investigation with most current works limited to laboratory experiments. The work herein shows the first documented study of AM 304L and 316L exposed to a severe marine environment on the eastern coast of Florida with comparisons made to wrought counterparts. Coupons were exposed for 21 months and resulted in significant pitting corrosion to initiate after 1 month of exposure for all conditions. At all times, the AM coupons exhibited lower average and maximum pit depths than their wrought counterparts. After 21 months, pits on average were 4 μm deep for AM 316L specimen and 8 μm deep for wrought specimen. Pits on the wrought samples tended to be nearly hemispherical and polished with some pits showing crystallographic attack while pits on AM coupons exhibited preferential attack at melt pool boundaries and the cellular microstructure.

Remodeling of t-system and proteins underlying excitation-contraction coupling in aging versus failing human heart

It is well established that the aging heart progressively remodels towards a senescent phenotype, but alterations of cellular microstructure and their differences to chronic heart failure (HF) associated remodeling remain ill-defined. Here, we show that the transverse tubular system (t-system) and proteins underlying excitation-contraction coupling in cardiomyocytes are characteristically remodeled with age. We shed light on mechanisms of this remodeling and identified similarities and differences to chronic HF. Using left ventricular myocardium from donors and HF patients with ages between 19 and 75 years, we established a library of 3D reconstructions of the t-system as well as ryanodine receptor (RyR) and junctophilin 2 (JPH2) clusters. Aging was characterized by t-system alterations and sarcolemmal dissociation of RyR clusters. This remodeling was less pronounced than in HF and accompanied by major alterations of JPH2 arrangement. Our study indicates that targeting sarcolemmal association of JPH2 might ameliorate age-associated deficiencies of heart function.

Time-dependent modeling and experimental characterization of foamed EPDM rubber

Foamed rubber with a mixed cellular microstructure is a compressible material used for various sealing applications in the automotive industry. For technical optimization, a sufficiently precise material model is required. Here a material description for the porous elastic and viscoelastic response of low density foamed rubber is proposed and adapted to ethylene propylene diene monomer (EPDM)-based rubber. The elastic description is based on a spherical shell model which is homogenized in an analytical and also in a numerical manner. A viscoelastic contribution accounts for the time-dependence of the material’s response. The derived constitutive model is implemented in a finite element software and calibrated experimentally with multi-step relaxation tensile tests of foamed EPDM rubber.

Facile Fabrication of Superhydrophobic Cross-Linked Nanocellulose Aerogels for Oil–Water Separation

A facile and environmental-friendly approach was developed for the preparation of the cross-linked nanocellulose aerogel through the freeze-drying process and subsequent esterification. The as-prepared aerogel had a three-dimensional cellular microstructure with ultra-low density of 6.05 mg·cm−3 and high porosity (99.61%). After modifying by chemical vapor deposition (CVD) with hexadecyltrimethoxysilane (HTMS), the nanocellulose aerogel displayed stable super-hydrophobicity and super-oleophilicity with water contact angle of 151°, and had excellent adsorption performance for various oil and organic solvents with the adsorption capacity of 77~226 g/g. Even after 30 cycles, the adsorption capacity of the nanocellulose aerogel for chloroform was as high as 170 g/g, indicating its outstanding reusability. Therefore, the superhydrophobic cross-linked nanocellulose aerogel is a promising oil adsorbent for wastewater treatment.

Functional Characterization of Marigold Powder as a Food Ingredient for Lutein-Fortified Fresh Noodles

Marigold powder was utilized as a food ingredient to produce lutein-fortified fresh noodles for eye health, and its functionalities were characterized in terms of thermo-rheological, structural, and antioxidant properties. The pasting parameters and starch-gelatinization enthalpy values of wheat flour had a tendency to decrease with increasing levels of marigold powder. The use of marigold powder led to decreases in the storage and loss moduli of wheat flour pastes by weakening their cellular microstructure, which was confirmed by the scanning electron microscopic images. When marigold powder was incorporated into the formulation of fresh noodles, the cooking loss and water absorption of the noodles were not negatively affected at a level of 2% (w/w). Also, the noodles with 2% marigold powder were not significantly different from the control for the maximum resistance to extension. The levels of lutein in the noodles prepared with marigold powder (61.2 to 204.9 mg/100 g) were reduced by almost 50% after cooking. However, they seemed to satisfy the recommended daily dose of lutein for visual functions. Moreover, the use of marigold powder provided antioxidant properties for noodles by enhancing the 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical-scavenging activities.