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Both shock and shockless compression experiments were performed on laser powder bed fusion (LPBF) Ti–5Al–5V–5Mo–3Cr (Ti-5553) to peak compressive stresses near 15 GPa. Experiments were performed on the as-built material, containing a purely β (body centered cubic) microstructure, and two differing heat treatments resulting in a dual phase α (hexagonal close packed) and β microstructure. The Hugoniot, Hugoniot elastic limit (HEL), and spallation strength were measured and compared to wrought Ti-6Al-4V (Ti-64). The results indicate the LPBF Ti-5553 Hugoniot response is similar between heat treatments and to Ti-64. The HEL stress observed in the LPBF Ti-5553 was considerably higher than Ti-64, with the as-built, fully β alloy exhibiting the largest values. The spallation strength of the LPBF Ti-5553 was also similar to Ti-64. Clear evidence of initial porosity serving as initiation sites for spallation damage was observed when comparing computed tomography measurements before and after loading. Post-mortem scanning electron microscopy images of the recovered spallation samples showed no evidence of retained phase changes near the spall plane. The spall plane was found to have kinks aligned with the loading direction near areas with large concentrations of twin-like, crystallographic defects in the as-built condition. For the heat-treated samples, the concentrations of twin-like, crystallographic defects were absent, and no preference for failure at the interface between the α and β phases was observed. [ABSTRACT FROM AUTHOR]

ScN in the rock salt structure is a well-investigated material due to its desirable properties like the high hardness or large thermal conductivity. Recent computations by Adamski et al. [Appl. Phys. Lett. 115, 232103 (2019)] showed that ScN/GaN heterostructures exhibit an outstanding polarization gradient which would be beneficial for polarization induced electron gases. The pseudobinary semiconductor Sc x Al 1 − x N, when maintaining the cubic rock salt structure, could be beneficial for tailoring the polarization gradient using the Sc dependency of material properties. The structural properties of rs-Sc x Al 1 − x N are not fully discovered yet, thus in this work, DC-magnetron sputtered cubic rock salt Sc x Al 1 − x N thin films with 0.55 < x < 1.00 were grown and analyzed on ScN(111)/Si(111). The epitaxial relation of ScN(111) thin films on the Si(111) substrate is determined to be ScN[110] ∥ Si[100]. Furthermore, concentration dependent properties like the lattice parameter of Sc x Al 1 − x N were measured [a(ScN) = 4.50 Å, a(Sc0.55Al0.45N) = 4.30 Å] and the stress σ within the layers was determined. The crystal quality was evaluated using ω -scans, revealing FWHM = 1.14 ° for Sc0.95Al0.05N. The diameters of the columns were determined by atomic force microscopy and scanning electron microscopy and they are range from 34 to 59 nm for 0.55 < x < 1.00. At x = 0.55 , Sc x Al 1 − x N columns in the hexagonal wurtzite as well as cubic rock salt structure were detected. This information about the structural specifications of Sc x Al 1 − x N in the rock salt structure forms the basis for further investigations and experimental confirmation of the electric properties of ScN/GaN heterostructures or even a Sc x Al 1 − x N/GaN based approach for improved structures for high-electron-mobility transistors. [ABSTRACT FROM AUTHOR]

This study investigates the structural stability of the CeO2-ZrO2 system when subjected to high doses of irradiation (a few hundred displacements per atom). The goal is to explore their potential use in safe immobilization of spent nuclear fuel and development of accident-tolerant fuels for next-generation nuclear reactors. Highly dense pellets were synthesized using a solid-state reaction and then irradiated with 1.75 MeV Xe5+ ions at ion fluences ranging from 1 × 1015 to 1 × 1017 ions/cm2. Structural and microstructural analyses were conducted using glancing angle x-ray diffraction, micro-Raman spectroscopy, and scanning electron microscopy. The results indicate that Ce0.8Zr0.2O2 has a high tolerance against irradiation-induced phase transformation or amorphization but does generate irradiation-induced point defects. Each energetic ion produced a deformed region with a voluminous swelling of ∼0.61 ± 0.09 nm and a damaged zone of ∼0.09 ± 0.02 nm, as calculated from the irradiation-caused peak broadening that is explained by a three-step damage accumulation model. The electron microscopy studies show that grain boundaries serve as a sink for defects, and an increase in grain size was observed due to defect accumulation inside the grain's volume. Overall, the study shows that polycrystalline fluorite-structured Ce0.8Zr0.2O2 is a promising nuclear material for advanced energy systems as it did not show significant structural damage such as amorphization and grain fragmentation, even on irradiation at a high dose of ∼428 dpa. [ABSTRACT FROM AUTHOR]

Mixed valence manganites are potential functional materials due to their unique electromagnetic properties. In this work, half-doped ceramics with the perovskite structure Sm 0.5 Ca 0.5 MnO 3 polycrystalline samples are synthesized by the solid-state reaction method in open air at different final sintering temperatures. Structures and particle sizes are studied by x-ray diffraction and scanning electron microscopy, respectively. Positron annihilation spectroscopy and density-functional theory calculations are used to characterize the intrinsic vacancies in the bulk. Thereafter, the effect of vacancies on the magnetic and magnetoresistance (MR) properties is investigated. We find that Mn monovacancies (V Mn ) exist in the bulk among all the samples, and the concentration of V Mn is different. We suggest a possible defect model that can be well applied to explain the phenomena of their electromagnetic properties. The transition temperature of the charge-order state (T CO ) and ferromagnetic and anti-ferromagnetic (T N ) are most likely related to the concentration of V Mn and the particle sizes or pore sizes, respectively. The glass spin state transition temperature seems to be independent of the defect concentration and type. The metal conductive behavior does not appear in a high magnetic field and at low temperatures, which may be caused by the presence of a high concentration of V Mn in the bulk and oxygen-related defects in the boundary, and the double exchange interaction is suppressed. At temperatures below T N and under a weak magnetic field, the MR is related to the total defect concentration. In addition, the high concentration of V Mn is unfavorable for obtaining a high MR value. [ABSTRACT FROM AUTHOR]

The structure, composition, and spatial distribution heterogeneity of artificial pinning centers affect the critical current density of REBa2Cu3O7−y (RE: rare earth) coated conductors. Nanoscale structures and compositions have been analyzed with transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). However, microscale heterogeneity has been difficult to characterize. Here, YBa2Cu3O7−y thin films doped with double-perovskite Ba2YbNbO6 were prepared via pulsed-laser deposition and characterized with TEM, STEM, and scanning electron microscopy (SEM). Cross-sectional and plan-view TEM/STEM imaging revealed hybrid pinning structures consisting of nanorods, nanoparticles, and planar defects that were formed spontaneously. Nanorods were imaged with high spatial resolution via field-emission SEM of thin-foil specimens. Focused-ion-beam (FIB) micro-sectioning enables SEM imaging of microscale heterogeneity in nanorod spatial distributions. By using TEM/STEM in conjunction with FIB-SEM, the coated conductor inhomogeneity was directly evaluated from the nano- to micrometer scales. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is one of the major health problems associated with patient care. In this context, researchers are interested in developing novel, effective and sustainable therapeutic nanoformulations. It has been observed that chitosan, polyvinyl alcohol, copper oxide and Acalypha indica (AI) extract have proven antimicrobial efficacy either individually or in combination. The presented study was focused on development of chitosan/PVA/CuO-AI nanocomposite for antimicrobial activity. In addition, hemolytic activity of the nanocomposite was also determined. Scanning electron microscopy, Fourier-transform infrared spectroscopy and X-ray crystallography confirmed the preparation of the nanocomposite. In addition, the chitosan/PVA/CuO-AI nanocomposite demonstrated effective antimicrobial activity and it was not hemolytic on human blood samples. Moreover, the cytotoxicity assay performed on Danio rerio gill cell line recorded 85% cells viability and no significant morphological alterations were observed. [ABSTRACT FROM AUTHOR]

The new class of microfiltration (MF) membranes based on nanofibrous sub-layers was investigated in this study. To this end, polyethylene terephthalate (PET) nanofibrous layers were produced via electrospinning technique based on PET supports as baking material, and subsequently, the solvent vapor treatment was applied for pore size modification of nanofibrous membranes. Capillary flow porometry and scanning electron microscopy were used to evaluate of pore size and morphology of the membranes, respectively. Moreover, filtration performance was evaluated by water flux and microparticle/bacteria retention. The results showed that average pore size of PET electrospun nanofibrous membrane was greatly reduced from 1.2 to 0.4 µm during modification process. Solvent vapor-treated MF membranes show significantly higher flux and acceptable rejection compared to commercial MF membranes. [ABSTRACT FROM AUTHOR]

Wearing appropriate personal protective equipment (PPE) for spraying pesticides is one of the methods to reduce dermal exposure to toxic pesticides. The main issues with such PPEs are comfortability and durable functionality. These issues were addressed by developing a bi-layer fabric treated with functionalized iron molybdate (Fe2(MoO4)3) nanoparticles (NPs). Three structures of bi-layer fabrics were developed to get the most comfortable fabric one with an upper layer of cotton (1*1 woven) and an underlayer of polyester (3/1 twill weave). The Fe2(MoO4)3 NPs were synthesized and functionalized with two silanes, i.e., Octadecyltrimethoxysilane and 1,2 Bis(triethoxysilyl)ethane. Fourier transform-infrared spectroscopy and thermogravimetric analysis were done to confirm the binding of silanes with NPs. Functionalized Fe2(MoO4)3 NPs were coated on selected fabric by dip-dry coating, and surface topography was assessed by Scanning Electron Microscopy (SEM). The water contact angle of 151° was exhibited by modified fabric. The photocatalysis of Benzoepin (C9H6Cl6O3S) by Fe2(MoO4)3 NPs under visible light was 75%. The UPF values obtained were 55 and 50 before and after washing, respectively. The developed superhydrophobic fabric could be efficiently used for durable pesticide-resistant clothing because the pesticide would not be adsorbed/absorbed by the fabric. If absorbed it could be possibly degraded by Fe2(MoO4)3 NPs rescuing the wearer from the hazardous effects of pesticides as well as UV rays. [ABSTRACT FROM AUTHOR]

In this study, β-SiAlON/aluminum nitride (AlN) composite ceramics were synthesized using a wet-mixing method at 1500 °C under a N 2 atmosphere. X-ray diffraction and scanning electron microscopy were used to characterize the ceramics before and after immersing them in water for 7 d. The change in pH and release of ammonia nitrogen were studied to investigate the reaction and antibacterial mechanisms of AlN hydrolysis. The effects of the AlN content on the phase composition, microstructure, chemical properties, and antibacterial efficacy of the composite ceramics were investigated. As the AlN content increased, the antibacterial efficiency gradually increased. The antibacterial efficiency of the composite ceramic with an AlN content of 60 wt% was 100%, indicating that an increase in pH and amount of ammonia nitrogen could synergistically enhance the antibacterial effect. However, in a lysogeny broth medium, the buffering effect of the culture medium and promotion of bacterial proliferation may reduce the antibacterial efficiency. Therefore, β-SiAlON/AlN composite ceramics show considerable potential for antibacterial applications. [ABSTRACT FROM AUTHOR]

Research on lead-free double perovskite has demonstrated its potential as a solution to the stability and toxicity issues associated with lead-based inorganic perovskite white light-emitting diodes (WLED). This current investigation was designed to fabricate, examine, and compare the photoluminescence (PL) characteristics of Cu2+-activated Rb 2 BB'Br 6 (B = K and B′ = Bi) double-perovskite (DP) [A 2 BB'Br 6 ] luminous materials. Bi3+ ions are substituted with Cu2+ ions at their B′ sites. These ions are distributed to the equilibrium valence state and demonstrate minimal variation in ion radius. The microstructure and phase purity of Rb 2 BB'Br 6 :Cu2+ DP were assessed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The Rietveld refinement was also used to identify the crystal structures, and the resulting samples all exhibit cubic crystal structures. The Fm3m space group in Rb 2 BB'Br 6 DP frameworks is significantly impacted by the B sites. The PL spectra were used to thoroughly examine the associated mechanism of the Cu2+ → Bi3+ energy-transfer process. Cu2+ ions can be successfully doped in the Rb 2 KBiBr 6 host with an optical band gap (E g) of 2.74 eV (RKBBr: 0.025Cu2+). The Rb 2 KBiBr 6 :Cu2+ phosphor exhibits distinct emission bands from 450 to 650 nm upon UV excitation at 366 nm. The Cu2+→ Bi3+ energy transfer design allows for systematic luminescence tuning from blue to white due to spectral overlap between the Cu2+ emission and Bi3+ excitation spectra. It has been established that Cu2+ → Bi3+ energy transfer significantly increases the white emission intensity of Bi3+, with an associated colour temperature of 7892 K and an outstanding colour rendering index of 88.8. As a down-conversion luminous material in solid-state illumination for the upcoming generation of display devices, the discovered Rb 2 KBiBr 6 : 0.025Cu2+ phosphor exhibits remarkable promise. [ABSTRACT FROM AUTHOR]

In this work, CuO nanoparticles (CuO-NPs) were synthesized at 400 °C using a modification of the polymer complex-Pechini method. Considering the procedure used, a mechanism was proposed to explain the formation of CuO-NPs. The synthesized nanoparticles were characterized using IR, Raman and UV–Vis spectroscopies, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicated that the sample synthesized contained CuO as the only crystalline phase, with a crystallite size between 9.17 and 14.95 nm, depending on the crystallographic direction and gap energy values of ∼4 eV and ∼5.86 eV. The CuO powder had agglomerates, in the order of microns, and primary particles smaller than 100 nm, with irregular morphology. The CuO synthetized was not stoichiometric and that it had an excess of oxygen, indicating the presence of cation vacancies and/or interstitial oxygen. The study of the capacity of CuO-NPs to remove methylene blue (MB), without irradiating the system with UV–Vis and without the presence of H 2 O 2 , showed that these promoted a percent removal of ∼39% in a basic medium (pH ∼9.7). [ABSTRACT FROM AUTHOR]

In this work, the color effects of novel Fe 2 O 3 /flake α-Al 2 O 3 pearlescent pigments prepared with different Fe salts and colorant dosages were investigated. First, Fe 2 O 3 /flake α-Al 2 O 3 pearlescent pigments with hexagonal flakes were successfully prepared by liquid-phase deposition. Second, the color effects of these pearlescent pigments were systematically investigated by changing the Fe salt and its dosage. The surface morphology, elemental distribution, and phase structures of the pigments were comprehensively characterized by scanning electron microscopy, energy-dispersive spectroscopy, and x-ray diffractometry. The results show that the color intensity of the pigments is affected by the Fe salt and its dosage. In addition, pigments prepared from different Fe salts show different colors. The color of the pigments was found to gradually deepen with increasing colorant dosage, and the pearlescent pigments obtained showed rich color effects. Therefore, different colors can be obtained by varying the colorants and their dosage, and this in turn enables the controllable preparation of different colors. Finally, the possible formation mechanism of the color effects was considered. Due to the different hydrolysis ability of the different colorants, the amount of Fe(OH) 3 generated by hydrolysis is different for each; thus, different coating ratios are obtained, resulting in different color effects. The results of this study provide a strong reference for the preparation of high-end pearlescent pigments and the modulation of their colors. [ABSTRACT FROM AUTHOR]

In this study, ceramic materials of Mg(Ti0.99Sn0.01)O3 were synthesized and decorated on reduced graphene oxide, forming a nanocomposite of rGO/Mg(Ti0.99Sn0.01)O3 (rGO/MTS001). The successful synthesis results were confirmed by XRD, UV–vis analysis, FT-IR, and SEM-EDS. The MTS001 has a flower-like morphology from scanning electron microscopy (SEM) analysis, and the nanocomposites of rGO/MTS001 showed MTS001 particles decorated on the rGO's surface. The electrochemical performance of rGO/MTS001 and MTS001 was investigated by determining the specific capacitance obtained in 1 M H2SO4 solution by cyclic voltammetry, followed by galvanostatic charge–discharge analysis using a three-electrode setup. The rGO/MTS001 achieved a specific capacitance of 361.97 F g‒1, compared to MTS001 (194.90 F g‒1). The capacitance retention of rGO/MTS001 nanocomposite also depicted excellent cyclic stability of 95.72% after 5000 cycles at a current density of 0.1 A g‒1. The result showed that the nanocomposite of ceramics with graphene materials has a potential for high-performance supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

The precise synthetic control of yttrium oxide (Y 2 O 3) nanotube morphology is essential for their practical application. A comprehensive investigation into the growth mechanisms of these nanotubes is crucial for directing the regulation of their morphology. In this study, Y 2 O 3 nanotubes were successfully synthesized. The morphological evolution was characterized through scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED), which elucidated the growth mechanism underlying the transformation from Y 4 O(OH) 9 (NO 3) nanosheets to nanotubes. The initiation of this process involves lattice distortions within the nanosheets, resulting in a spontaneous curling phenomenon driven by the minimization of surface energy. The presence of NaOH in the reaction milieu initiates a topotactic transformation, resulting in the conversion of the Y 4 O(OH) 9 (NO 3) nanosheets into Y(OH) 3 nanotubes. Subsequent calcination induces a phase transition from hexagonal Y(OH) 3 to cubic Y 2 O 3 phases, while preserving the tubular structure. These findings offer strategic insights into the controlled synthesis of nanomaterials. [ABSTRACT FROM AUTHOR]

Structural and electrochemical properties of bismuth ferrite nanostructures produced by pulsed laser deposition with various morphologies are reported. The nanostructures are also explored as electrode materials for high-performance supercapacitors. Scanning electron microscopy images revealed that various bismuth ferrite morphologies were produced by varying the background pressure (10−6, 0.01, 0.10, 0.25, 0.50, 1.0, 2.0 and 4.0 Torr) in the deposition chamber and submitting them to a thermal treatment after deposition at 500 ◦C. The as-deposited bismuth ferrite nanostructures range from very compact thin-film (10−6, 0.01, 0.10 Torr), to clustered nanoparticles (0.25, 0.50, 1.0 Torr), to very dispersed arrangement of nanoparticles (2.0 and 4.0 Torr). The electrochemical characteristic of the electrodes was investigated through cyclic voltammetry process. The increase in the specific surface area of the nanostructures as background pressure in the chamber increases does not lead to an increase in interfacial capacitance. This is likely due to the wakening of electrical contact between nanoparticles with increasing porosity of the nanostructures. The thermal treatment increased the contact between nanoparticles, which caused an increase in the interfacial capacitance of the nanostructure deposited under high background pressure in the chamber. [ABSTRACT FROM AUTHOR]

In the present study, to promote sustainable nano-farming, the apparent effects of different concentrations (0, 100, 200, 300, 400, 500 ppm) of titanium dioxide nanoparticle (TiO2NPs) solutions on the germination percentage, index and duration of seeds belonging to Balcı, Dincer, Hasankendi, Koc, Olas, and Zirkon safflower varieties were investigated. Moreover, scanning electron microscopy (SEM) was employed to analyze TiO2NPs in germinated safflower varieties. Germination performance was TiO2NPs concentration and variety depended. It was determined that the seed samples displayed different responses to TiO2NPs concentrations; germination percentages were between 20.0±1.15 and 82.9±0.44%, germination durations were between 2.01±0.021 to 3.82±0.017 days, and germination indices were between 9.97±0.606 and 38.97±0.959. While the highest germination percentage (82.9±0.44%) was obtained from Dincer variety with 100 ppm TiO2NP pre-application, the lowest germination percentage (20.0±1.15% and 20.0±1.92%) was obtained from Balcı and Hasan Kendi varieties with 100 and 300 ppm TiO2NP pre-application. According to this result, although the highest germination percentage based on variety was obtained from the Dincer variety, the Balcı variety with the lowest germination percentage provided the most significant increase in the 200 ppm TiO2NPs application dose compared to the control. According to the germination percentage, it can be said that the most effective TiO2NPs application dose in Safflower varieties is 200 ppm. Further research on nanoparticles is needed to determine both the economical doses of TiO2NP pre-application and its uptake by the plant. [ABSTRACT FROM AUTHOR]

• Pollen morphology of genera Oreobliton, Aphanisma, Beta, Hablitzia, and Patellifolia (Betoideae, Amaranthaceae) was studied using LM and SEM. • Two types of exine sculpture were observed: nanoechinate and psilate. • Three pollen types (Hablitzieae, Corollinae, Beta/Macrocarpae) were revealed. • Diagnostic pollen characters separating the tribes Hablitzieae and Beteae were exine thickness and structure of columellae. • Cluster analysis supports the differentiation of sections Corollinae, Beta, and Macrocarpae. Pollen morphology of 10 taxa belonging to the genera Oreobliton, Aphanisma, Beta, Hablitzia , and Patellifolia (subfamily Betoideae, Chenopodiaceae/Amaranthaceae sensu APG IV) was investigated using both light and scanning electron microscopy. The research aimed to provide data on their pollen characteristics and to evaluate their significance for taxonomy and phylogeny. All pollen grains are pantoporate, spheroidal in shape, usually circular in outline (rarely polygonal), small and medium-sized. Two types of exine sculpture were recognised: type I – nanoechinate, and type II – psilate. For the first time, a psilate type of exine sculpture was revealed in the pollen grains of a member of subfam. Betoideae (Beta macrocarpa). Three pollen types (I – Hablitzieae, II – Corollinae, and III – Beta/Macrocarpae) were found and described based on the pollen diameter, pore diameter, distance between pores and between pore centres, pore number, C/D value, exine thickness, nanoechini: height, width at the base, number/4 µm², and number on pore membranes. The diagnostic pollen characters that separate the tribes Hablitzieae and Beteae are: exine thickness and structure of columellae. UPGMA dendrogram, based on quantitative pollen traits, supports the differentiation of most taxa at genera and species level. UPGMA dendrogram, based on qualitative palynological data, supports the differentiation of sections Corollinae, Beta, and Macrocarpae. The pollen morphology of Aphanisma blitoides, Beta lomatogona, B. macrocarpa, B. macrorhiza, Oreobliton thesioides , and Patellifolia patellaris , was studied for the first time in the present investigation. [ABSTRACT FROM AUTHOR]

Objectives: To assess the growth of a multispecies biofilm on root canal dentin under different radiotherapy regimens. Materials and methods: Sixty-three human root dentin cylinders were distributed into six groups. In three groups, no biofilm was formed (n = 3): NoRT) non-irradiated dentin; RT55) 55 Gy; and RT70) 70 Gy. In the other three groups (n = 18), a 21-day multispecies biofilm (Enterococcus faecalis, Streptococcus mutans, and Candida albicans) was formed in the canal: NoRT + Bio) non-irradiated + biofilm; RT55 + Bio) 55 Gy + biofilm; and RT70 + Bio) 70 Gy + biofilm. The biofilm was quantified (CFUs/mL). Biofilm microstructure was assessed under SEM. Microbial penetration into dentinal tubules was assessed under CLSM. For the biofilm biomass and dentin microhardness pre- and after biofilm growth assessments, 45 bovine dentin specimens were distributed into three groups (n = 15): NoRT) non-irradiated + biofilm; RT55 + Bio) 55 Gy + biofilm; and RT70 + Bio) 70 Gy + biofilm. Results: Irradiated specimens (70 Gy) had higher quantity of microorganisms than non-irradiated (p =.010). There was gradual increase in biofilm biomass from non-irradiated to 55 Gy and 70 Gy (p <.001). Irradiated specimens had greater reduction in microhardness after biofilm growth. Irradiated dentin led to the growth of a more complex and irregular biofilm. There was microbial penetration into the dentinal tubules, regardless of the radiation regimen. Conclusion: Radiotherapy increased the number of microorganisms and biofilm biomass and reduced dentin microhardness. Microbial penetration into dentinal tubules was noticeable. Clinical relevance: Cumulative and potentially irreversible side effects of radiotherapy affect biofilm growth on root dentin. These changes could compromise the success of endodontic treatment in oncological patients undergoing head and neck radiotherapy. [ABSTRACT FROM AUTHOR]

A freeze-dried, platelet-derived hemostatic agent (FPH) was developed for acute hemorrhage. The canine product (cFPH) was developed for use in preclinical models supporting human product (hFPH) investigations. A carotid artery bypass graft (CABG) study in dogs compared 3 dosages of cFPH to canine liquid stored platelets (cLSP) and vehicle (VEH) control groups. Histopathological analysis and blood loss assessments were completed. A separate ex-vivo synthetic graft study assessed thrombogenicity via blood from human and canine donors that was combined with species-specific FPH or apheresis platelets. Characterization of cFPH and hFPH included thrombin generation, total thrombus formation, and scanning electron microscopy. Blood loss was reduced in CABG dogs receiving standard of care (cLSP) or cFPH treatment compared to VEH control; a cFPH dose effect signal was observed. Further, cFPH dosing up to 5 × 109 cells/kg was not associated with increased mortality or occlusion of the anastomosis sites, and histopathologic evidence of off-target thrombosis was not detected. When passed through a synthetic graft (ex vivo), whole blood combined with species-specific FPH did not result in thrombosis beyond that of whole blood control. In vitro testing and imaging of cFPH and FPH were comparable. A single dose of cFPH or cLSP reduced blood loss in a pilot surgical study and was well tolerated with no related adverse events. Further, the hemostatic activity and characteristics of cFPH are comparable to that of hFPH, suggesting that research findings from the canine product are likely to inform the development of the human product. [Display omitted] • Canine freeze-dried platelet-derived hemostat reduced blood loss in a pilot cardiac surgical study. • Canine freeze-dried platelet-derived hemostat is a surrogate to evaluate the human product in surgical bleeding. • Canine freeze-dried platelet-derived hemostat does not induce off-target thrombosis. [ABSTRACT FROM AUTHOR]

The prevalence of Alzheimer's disease (AD) in developed and developing nations is increasing day by day. The monotherapy doesn't fit best for AD due to chronic treatment. This work aimed to prepare the liposomes coloaded with Donepezil and pine oil intended for adjuvant effect. Pine oil was selected due to its amyloid disaggregation and AChE inhibition property. The thin film hydration method with sonication was selected to formulate ultra-small-sized unilamellar vesicles. Apart from this formulated vesicle were subject to particle size, morphological, release, nasal ciliotoxicity and cellular uptake studies. The PDI, particle size, and zeta potential of the final egg lecithin-based liposome were found to be 0.19, 129 nm, and -27.5 mV, respectively, stable at 4° and 25°C. SEM microscopy of oil-loaded liposomes exhibits a crystalline cubic shape and is compared with alone drug-loaded liposomes that are spherical. AChE inhibition activity was found to be higher in combination when compared with others. The prepared liposomes were safe when studied for nasal ciliotoxicity studies and rapid uptake by C6 cells with complete internalization. This study demonstrated the development and potential of the vesicular system that carries valuable characteristics and overcomes patient compliance concerns that prove to be novel therapeutics for managing AD. [ABSTRACT FROM AUTHOR]

In the industrial application of bacterial cellulose (BC), the yield becomes a crucial factor because it drives the selling price of BC. A Box–Behnken experimental design with three components and three levels was employed to create seventeen samples. A response surface method was then used to optimize the BC yield from the most relevant parameters, including incubation temperature, medium shaking intensity, and nitrogen supply pH. Fourier transform infrared (FTIR) analysis proved that BC was pure. By analyzing BC morphology using scanning electron microscopy (SEM), rod-like microfibrils with an average diameter of 6.5 were revealed. X-ray diffraction (XRD) tested the crystalline size and crystallinity and found 4.7 nm and 69%, respectively. Thermal transition and stability were assessed using a differential scanning calorimeter (DSC) and a thermogravimetric analyzer (TGA). For the manufacture of BC composite hydrogel, a chemical test method was used to determine the solubility of BC. This study aimed to identify the ideal circumstances for using leftover sweet lime pulp for biomedical applications to produce reasonably priced and effective BC. At 28.87 °C, 125.91 rpm shaking frequency, and 5.65 pH, a sweet lime pulp waste medium produced the highest yield of BC, three times greater than the yield in a Hestrin–Schramm medium under static circumstances. [ABSTRACT FROM AUTHOR]

This study aimed at examining the bond strength between zirconia and ceramic veneer, following the ISO 9693 guidelines. A total of fifty specimens of zirconia/ceramic‐veneer system were produced using two commercial zirconias (VITA YZ‐HTWhite and Zolid HT+ White, referred to as Group A and Group B, respectively) and a ceramic‐veneering material (Zirkonia 750). The microstructure (via x‐ray diffraction analysis, XRD and Secondary Electron mode, SEM) and the mechanical properties (via 3‐point bending tests) of the two groups were assessed. Then, experiments were conducted according to the ISO 9693 and conventional protocols applied for producing zirconia/ceramic‐veneer restorations. Bond strength values, measured by 3‐point bending tests, were 34.42 ± 7.60 MPa for Group A and 31.92 ± 6.95 MPa for Group B. SEM observations of the cohesively fractured surfaces (on the porcelain side) and the examination for normality using the Shapiro–Wilk test suggested the use of Weibull statistical analysis. Median strength (σ50%) for Group A and Group B was 34.76 and 32.22 MPa, while the characteristic strength (σ63.2%) was 35.78 and 33.14 MPa, respectively. The Weibull modulus disparity between groups (12.69 and 13.07) was not significant. Bond strength exceeded the ISO 9693 minimum of 20 MPa, suggesting satisfactory strength for clinical use. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effect of four different strategies for bonding a CAD/CAM resin nanoceramic restoration (Lava Ultimate, 3M) to the dentin surface using a universal adhesive (Scotch Bond Universal, 3M) and adhesive resin cement (RelyX Ultimate, 3M) on the shear bond strength (SBS) and failure mode. The strategies comprised: (i) immediate sealing, immediate bonding; (ii) immediate sealing, bonding after 2 weeks with provisional restoration; (iii) immediate sealing with flowable resin composite reinforcement and bonding after 2 weeks with provisional restoration; and (iv) no immediate sealing, and bonding after 2 weeks with provisional restoration. After bonding, all the specimens were thermocycled, shear tests were performed using a universal testing machine, and failure modes were determined using stereomicroscope and scanning electron microscopy. The highest mean SBS was recorded with immediate sealing, immediate bonding strategy. Most adhesive failures with exposed dentinal tubules were noted in specimens exposed to bonding after 2 weeks with no immediate sealing, which was associated with the lowest SBS. Mixed failures predominated in all immediate dentin sealing groups. Immediate sealing with universal adhesives improves SBS, particularly in the single‐visit approach, which has shown significantly better performance, whereas the provisional phase has a negative effect. [ABSTRACT FROM AUTHOR]

The characterization of carbonate production on rift basins is critical for understanding the nucleation and demise of reefs in tectonically active areas. A new petrographic and mineralogical analysis of Cambrian strata from the Avalon Zone in Newfoundland, based on scanning electron microscopy – back‐scattered electron detector and Raman spectrometer analyses, facilitates recognition of several episodes of Terreneuvian–Miaolingian carbonate production and associated precipitation of ironstone and phosphorite. These distinct units mainly developed on uplifted rift shoulders and basaltic lava palaeoreliefs, and reflect amalgamated high‐energy events, interrupted by scouring discontinuities (diastems) commonly lined by phosphatized and ferruginized microbial crusts. Mud‐mounds, in contrast, nucleated under calm conditions episodically punctuated by high‐energy episodes, where scattered thromboid structures occur as both clotted textures and distinct calcimicrobes. Precipitation of hematite/goethite versus chamosite couplets, both occluding primary porosities and replacing interlaminae and cortices of oncoids and coated aggregates, point to marine substrates close to the Fe‐redox boundary. Upwelling of phosphate‐rich ferruginous hydrothermal waters contributed to the precipitation of ironstone and phosphate interbeds. Ferruginous waters related to penecontemporaneous hydrothermal activity, reflected by the record of synsedimentary fissuring and stockwork ore bodies, were delivered to confined rift‐related horst‐and‐graben settings, largely controlled by the development of specific Cambrian carbonate and associated ironstone facies. The influence of ferruginous waters necessarily affected the record of climatically sensitive evaporitic pseudomorphs, reefs/mounds and phosphorites, which are then not suitable criteria to discriminate palaeolatitude, as demonstrated by a comparison of low‐latitude to middle‐latitude margins fringing Baltica, and the Avalonian and Atlas – Ossa‐Morena – Northarmorican rift transects of West Gondwana. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy (SEM) coupled with energy‐dispersive X‐ray spectroscopy (EDX) enables the determination of the composition and structure of tiny calcified remains occasionally recovered during burial excavations. To deepen the practical application of this technique, we performed SEM/EDX analysis on three different tiny mineralized, roughly rounded structures with a diameter of less than 5 mm recovered from a pre‐Hispanic collective funerary cave from El Hierro (Canary Islands) and a mineral spherulite of similar size and outer aspect. After SEM imaging and spectroscopic analysis, we conclude that the three samples represent a sesamoid bone, a kidney stone, and a possible case of sialolithiasis. In contrast, the spherulite is a mineral formation composed of calcium carbonate. Our data confirm SEM analysis's usefulness in identifying small, mineralized remains recovered during burial excavations and its contribution to studying past populations. However, we are aware that taphonomic changes may alter, at least partially, the structure, and/or elemental composition of archaeological samples, obscuring differential diagnosis. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the effects of different surface treatments on the repair bond strength between a fiber‐reinforced dentin composite and a posterior composite. Methods: Forty fiber‐reinforced dentin composite resin blocks (4 mm × 4 mm × 4 mm) were separated into eight groups (n = 5) according to the surface preparation methods: (G1) negative control group, (G2) adhesive application, (G3) 50% dimethylsulfoxide (DMSO) application, (G4) 50% DMSO + adhesive application, (G5) 37% phosphoric acid etch + adhesive application, (G6) air abrasion + adhesive application, (G7) 37% phosphoric acid etch + 50% DMSO application + adhesive application, and (G8) air abrasion +50% DMSO application + adhesive application group. The composite surfaces were repaired in two layers with a posterior composite. Composite sticks were subjected to a micro tensile bond strength (μTBS) test. Fractured surfaces were evaluated using a stereomicroscope (×25). Short fiber‐reinforced composite samples' surfaces were investigated by scanning electron microscope (SEM). Shapiro Wilk, one‐way ANOVA, and Tukey HSD tests were used for statistical evaluation. Results: The highest average (μTBS) values were observed in G8, whereas the lowest mean μTBS values were evident in the G1 group. Statistically significant μTBS values were found in all adhesive‐applied groups when compared with the negative control group. Notably, the application of 50% DMSO without adhesive did not lead to a statistically significant increase in μTBS values. SEM images demonstrated that acid etching partially eliminated residues on the composite surface, while air abrasion had a detrimental effect on the integrity of fiber structures. Conclusion: In the repair of fiber‐reinforced dentin composite with a posterior composite, adhesive application is an effective approach. The treatment of 50% DMSO without adhesive did not confer a statistically significant advantage, and the supplemental use of acid etch or air abrasion did not show an additional benefit compared to adhesive‐only repairs. Clinical Significance: Adhesive application emerges as a potent and effective strategy for the repair of bur‐roughened fiber‐reinforced dentin composites. With its limitations, the study highlights the efficacy of adhesive‐only repairs without the necessity for additional surface treatments. [ABSTRACT FROM AUTHOR]

The aim of this research was to produce a film based on the mucilage of Paneerak flower modified with licorice root and copper sulfate nanoparticles. The D-optimal statistical scheme was used to study the antioxidant, antimicrobial, X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and thermal decomposition (DSC) properties of the films. The results showed that with the increase of licorice root and copper sulfate nanoparticles, the antioxidant activity of the film increased significantly (p<0.05). The results of the antimicrobial activity of the prepared films showed that the addition of licorice and copper sulfate nanoparticles caused the antimicrobial activity of the film against Escherichia coli and Staphylococcus aureus. X-ray diffraction analysis shows that copper sulfate nanoparticles are physically combined with the mucilage polymer of Paneerak flower and it reduces the crystal structure.Fourier transform infrared (FTIR) results confirm the physical presence of copper sulfate nanoparticles in the polymer matrix. FTIR results also showed weak electrostatic interactions between film components and composites. The results of the scanning electron microscope (SEM) show that the surface of the films containing copper sulfate nanoparticles and licorice root are more heterogeneous than the mucilage of Paneerak flower. Shirin-bian and copper sulfate nanoparticles were able to delay the thermal decomposition of the mucilage of Paneerak flower and increase the thermal stability of the mucilage film. Finally, based on the results, the addition of copper sulfate nanoparticles and licorice root to edible films based on the mucilage of paneerak flower improved antimicrobial, antioxidant, DSC and SEM. [ABSTRACT FROM AUTHOR]

Anthocyanin is one of the bioactive compounds, which is the main pigment of many fruits and vegetables. Since anthocyanins have low thermal stability during food processing, the use of these compounds as natural pigments in foods is associated with challenges. Therefore, microencapsulation of anthocyanin compounds with liposomes is important. Nanoencapsulation of bioactive compounds with liposomes is an effective and efficient way to increase the stability of polyphenolic compounds. Liposomes are polar lipid vesicles that form bilayer structures in polar solvents such as water. In this research, nanoliposomes in ratios of 9-1, 8-2, 7-3 and 6-4 lecithin-cholesterol were prepared using the solvent injection method. Then, the size and zeta potential tests were conducted to determine the characteristics of the produced particles. The average particle size (average hydrodynamic diameter) and particle size distribution for different lecithin-cholesterol ratios were in the range of 132-740 nm and 0.47-0.41, respectively. Zeta potential values were also obtained in the range of -26 to -42 mv. After determining the efficiency of Nanoencapsulation, FTIR test was performed to investigate possible reactions between anthocyanins and nanoliposome wall materials. The morphology of anthocyanin-loaded lecithin-cholesterol nanoliposomes with a ratio of 9-1 was shown by scanning electron microscopy (SEM). The stability of the liposomal sample with a ratio of 9-1 lecithin-cholesterol was evaluated by calculating the amount of release of encapsulated anthocyanin during 60 days of storage at ambient temperature. Samples with 9-1 lecithin-cholesterol ratio were used in Kombucha beverage formulation. Sensory properties of prepared beverages were evaluated which the results showed among the samples, smell, mouthfeel and overall acceptance parameters had no significant difference (P>0.05) .The results obtained in this research showed that nanoliposomes are an efficient system for encapsulating of anthocyanins [ABSTRACT FROM AUTHOR]

To analyze the features of the epithelia coating neovaginas after vaginoplasty in women affected by Mayer-Rokitansky-Küster-Hauser syndrome We conducted a retrospective analysis of prospectively collected data. Women affected by Rokitansky syndrome who underwent neovaginal biopsy after vaginoplasty (McIndoe surgery, intestinal vaginoplasty, Vecchietti surgery, and Davydov surgery) were included. Macroscopic mucosal features were assessed through clinical examination and the Schilling test. Each biopsy specimen was prepared for examination by light microscopy and in some cases by scanning electron microscopy (SEM). Thirty-six patients (4 McIndoe, 2 intestinal vaginoplasty, 14 Vecchietti, and 16 Davydov) were included. All biopsies were performed without complications. In McIndoe's neovaginas, the mucosal microscopic features were similar to normal skin, with large areas of preserved epithelium, heterogeneous presence of dermal papillae, and superficial keratinization. The characteristics of the intestinal neovagina's surface were similar to those of a sigmoid colon, with well-shaped glands, cylindrical cells, and a secreting mucosa. In Vecchietti neovaginas, the surface the epithelium was flat and multilayered, highly similar to that of a normal vagina, with the presence of glycogen and superficial desquamation. On medium SEM magnification evaluation, the epithelium presented flattened polygonal cells. Finally, in Davydov neovaginas, none of the specimens had persistent mesothelial elements. The squamous neo-epithelium had regular aspects of differentiation with the presence of glycogen. At greater SEM magnification, microridges were evident, with a regular distribution. Each different technique of vaginoplasty leads to unique histological and structural features of the neovagina's mucosa. Knowledge of these elements must be the basis for the choice of the most appropriate intervention. [ABSTRACT FROM AUTHOR]

In the present work, we have developed for the first time a carbon ultramicroelectrode modified by a molecular imprinted polymer (MIP) for selective determination of 3-methyl-4-nitrophenol (MNP) in aqueous media. The polymeric film based on a non-covalent approach was obtained by electropolymerization of ortho-phenylenediamine in the presence of MNP to generate a template-polymer association on the electrode surface. Cyclic Voltammetry (CV) was used for MIP elaboration, performing 20 cycles in the range from 0 to 0.7 V versus Ag/AgCl/Cl−sat. After removing the template, we obtained a specific MNP recognition site on the modified microelectrode. The surfaces of the modified and unmodified microelectrodes were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Many parameters influencing the electropolymerization process were optimized. Square Wave Voltammetry (SWV) was used for the quantitative analysis of MNP with the optimized following parameters: frequency 50 Hz, potential amplitude 70 mV, and scan increment 15 mV. The peak current increased linearly with the MNP concentration in the range from 1 to 17 mg L−1, and the limit of detection (LoD) for MNP was calculated to be 0.69 mg L−1. The elaborated UME-MIP was applied to study the bioremediation of MNP in a fungal microbial fuel cell using a ligninolytic fungus Trametes trogii (strain CLBE 55). The obtained results showed a zero-order kinetic with a kinetic constant of 10.5 mg L−1 h−1 at 22 °C and a half-time degradation of 4.5 h under an optimal external resistance of 20,950 Ohm and a power density of 1.2 mW m−3. [ABSTRACT FROM AUTHOR]

The current work investigates the metallurgical and corrosion characteristics of the interface between Nickel foam and AA7075 alloy. Nickel foam is conjoined with AA7075 alloy (composite) through a melt-infiltration technique. The composite specimen is characterized for microstructure, microhardness, microhardness, exfoliation corrosion susceptibility, and electrochemical corrosion parameters, including corrosion potential, corrosion current density, and polarization resistance. Also, the influence of T6 heat treatment on the corrosion of the composite specimen is analyzed. The texture, morphology, and composition of the interface and corroded surface are comprehensively analyzed using instrumental analytical techniques such as Scanning Electron Microscopy (SEM), Electron Backscatter Diffraction (EBSD), Energy-Dispersive X-ray Spectroscopy (EDS), and X-ray diffraction. The results indicate that T6 heat treatment increases the corrosion resistance of the composite specimen. [ABSTRACT FROM AUTHOR]

Tissue susceptibility to histotripsy disintegration has been reported to depend on its elastic properties. This work was aimed at investigation of histotripsy efficiency for liquefaction of human hematomas, depending on their stiffness and degree of retraction over time (0–10 d). As an in vitro hematoma model, anticoagulated human blood samples (200 mL) were recalcified at different temperatures. In one set of samples, the shear modulus was measured by shear wave elastography during blood clotting at 10℃, 22℃ and 37℃, and then daily during further aging. The ultrastructure of the samples was analyzed daily with scanning electron microscopy (SEM). Another set of blood samples (50–200 mL) were recalcified at 37℃ for density and retraction measurements over aging and exposed to histotripsy at varying time points. Boiling histotripsy (2.5 ms pulses) and hybrid histotripsy (0.2 ms pulses) exposures (2 MHz, 1% dc, P +/ P –/ A s = 182/–27/207 MPa in situ) were used to produce either individual cigar-shaped or volumetric (0.8–3 mL) lesions in samples incubated for 3 h, 5 d and 10 d. The obtained lesions were sized, then the lysate aspirated under B-mode guidance was analyzed ultrastructurally and diluted in distilled water for sizing of residual fragments. It was found that clotting time decreased from 113 to 25 min with the increase in blood temperature from 10℃ to 37℃. The shear modulus increased to 0.53 ± 0.17 kPa during clotting and remained constant within 8 d of incubation at 2℃. Sample volumes decreased by 57% because of retraction within 10 d. SEM revealed significant echinocytosis but unchanged ultrastructure of the fibrin meshwork. Liquefaction rate and lesion dimensions produced with the same histotripsy protocols correlated with the increase in the degree of retraction and were lower in retracted samples versus freshly clotted samples. More than 80% of residual fibrin fragments after histotripsy treatment were shorter than 150 µm; the maximum length was 208 µm, allowing for unobstructed aspiration of the lysate with most clinically used needles. The results indicate that hematoma susceptibility to histotripsy liquefaction is not entirely determined by its stiffness, and correlates with the retraction degree. [ABSTRACT FROM AUTHOR]

Most of the materials used in landfill liners are not based on the local soil conditions which increases the cost of landfill construction. It is essential to develop a composite mix based on local soil that fulfills the design parameters of the municipal solid waste (MSW) landfill at a reasonable cost as per USEPA 1989 guidelines. The current study investigates the use of local soil, fly ash, and bentonite mixtures to obtain an optimum composite mix with specific properties for landfill liners. The experimental investigation was conducted on different proportions of local soil-bentonite-fly ash mixes to evaluate the optimum mix proportion for liner materials. The curing period of different mixes is also considered. The geotechnical properties like liquid limit (LL), free swell index (FSI), and optimum moisture content (OMC) increased whereas the maximum dry density (MDD) and permeability decreased with an increase in bentonite content up to 20% with soil. It was also observed that fly ash mixed with soil in proportion (80:20) meets the optimum range of landfill liner properties. And, the composite mix comprised of soil–bentonite–fly ash in proportion (65:15:20) directs toward the optimum design parameters of landfill liner. These mixes were compacted at OMC and MDD satisfying plasticity (i.e., LL ≥ 20% and plasticity index, PI ≥ 7%) and permeability criteria (k ≤ 1 × 10−7 cm/s) as well as unconfined compressive strength criteria. Moreover, the scanning electron microscopy of local soil–bentonite–fly ash mixes was investigated for the optimum mixes for a comparative assessment of results. [ABSTRACT FROM AUTHOR]

In this study, bismuth telluride–based hybrids consisting of nanosheets were successfully prepared by disproportionation induced by microwave irradiation and applied on supercapacitor electrodes. Various analytical techniques were adopted to analyze the structure and composition of Bi 2 Te 3 /Bi 2 TeO 5. The unique disproportionation (Te0→Te2++Te4+) results in an interlocking nanosheet, in which the lamellar interspersed structure on the lamella can be visualized through high-magnification scanning electron microscopy. The large layer spacing with the interspersed structure provides more storage sites for electrolyte ion interactions and allows for better stabilization of the electrode structure. Result of electrochemical studies indicates that Bi 2 Te 3 /Bi 2 TeO 5 enables a capacity of 860 F g−1 (1 A g−1) and maintains 74.5% of the initial capacity through 2000 charge/discharge cycles. The Bi 2 Te 3 /Bi 2 TeO 5 anode is integrated into an ultracapacitor to attain a remarkable energy density of 89 Wh kg−1 in 6 M KOH. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, heavy calcium carbonate was wet modified using a titanate coupling agent, and fabricated titanate-coupled calcium carbonate and styrene–butadiene–styrene (SBS) were used to prepare composite modified asphalt. Microscopic tests such as scanning electron microscopy and x-ray diffraction showed that the surface wrinkle of the modified calcium carbonate was significantly increased, and the enhanced crystallinity and purity were favorable for its compatibility with asphalt (by segregation). Viscosity (135°C) and three major indicator tests showed that the modified asphalt exhibited good high-temperature performance compared to the original asphalt. Dynamic shear rheological and multistress creep recovery tests indicated that the composite modified asphalt exhibited better viscoelastic properties and resistance to permanent deformation than the pure SBS-modified asphalt. This was attributed to the fact that the modifier caused the SBS to swell sufficiently to form a clearly visible three-dimensional spatial network structure in the asphalt (by fluorescence microscope). This allows the matrix asphalt to form an interlocking phase with the polymer modifier, which in turn significantly enhances the relevant properties of the asphalt, as confirmed by fluorescence microscopy. The results of Fourier infrared spectroscopy suggest that the modifier is only physically miscible with SBS or base asphalt. This study can provide a feasible idea for the practical application of bicarbonate composite modified asphalt, which has greater prospects in construction and highway applications. [ABSTRACT FROM AUTHOR]

Red mud has been used as a supplement substitute material in the fabrication of concrete. However, the influence mechanism of red mud on the film-forming performance of cement paste is still unclear. In this study, red mud with different substitution rates (by cement mass) was added to cement paste to investigate the influence of red mud on the film-forming performance. The addition of red mud increased the cohesiveness and reduced the fluidity of cement paste. It showed that low fluidity reduced the film thickness of cement paste, and the film thickness decreased gradually with the increase of red mud substitution. Moreover, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy results demonstrated that red mud promotes the hydration process of cement by providing hydration nucleation sites, making the interfacial transition zone denser, which is important for improving the mechanical properties of cement paste. It is expected that this study improves the application of red mud in concrete. [ABSTRACT FROM AUTHOR]

This study focused on the characterization of sulfur-modified mortars made with amorphous carbon powder (ACP). To this end, modified paste samples were fabricated initially with different ACP content through a dry mixing method, considering varying mixing times. The reinforcement efficiency was evaluated through X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses. Subsequently, the sulfur-modified mortar samples were prepared following the results of the paste assessment. A series of properties of modified and raw sulfur mortar samples, including mechanical performances and durability behaviors, were investigated. Microstructural investigation of the paste samples showed that the degree of modification increased by increasing the ACP content and reducing the mixing time. Results from mechanical measurements revealed that the addition of 20% ACP by weight of sulfur enhanced the compressive and flexural strengths of the mortar sample by up to 26% and 57%, respectively, which aligns with the outcomes from the helium porosimetry and ultrasonic pulse velocity (UPV) tests. The incorporation of ACP led to a significant reduction in the sorptivity and water absorption of the mortar samples by enhancing the hydrophobicity properties of the mortar. Durability assessments demonstrated that mortar samples containing ACP are less prone to corrosion damage compared with raw sulfur mortar. However, these positive effects were less pronounced in mortar samples including a large amount of ACP. [ABSTRACT FROM AUTHOR]

This study investigated the self-healing performance of nanosilica-modified engineered cementitious composites (ECCs) exposed to high temperatures. Nanosilica (NS) was used in 0%, 0.25%, 0.50%, and 0.75% proportions of cementitious materials by mass in the mixtures. NS-modified ECC cylindrical samples (Ø100×200 mm) were produced and cured at 23°C±2°C for 28 days. Then, these samples were exposed to 20°C±2°C , 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, and 800°C temperatures. After the samples were cooled at room temperature, microcracks were formed in the ECC samples, but the samples exposed to higher than 400°C were dispersed when the crack was formed. The wetting–drying cycles were applied for the self-healing of cracked samples. Lastly, the splitting tensile strength, ultrasonic pulse velocity, and chloride ion permeability of the NS-modified ECC samples were determined. Scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX), X-ray diffraction analysis (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses were also performed to examine the microstructure of NS-modified ECC samples. This study found that all samples were self-healed within 15 days, and the highest splitting tensile strength recovery rate was obtained from 0.75 NS-modified ECC samples with 107.44%. [ABSTRACT FROM AUTHOR]

It is important to study the steel corrosion inhibition behavior in complex chloride salt environments. This paper uses the fact that calcined layered double hydroxides (CLDHs) have a certain memory effect, which means that it can reabsorb water and anions and partially restore the lamellar structure under certain conditions. This work investigated the influence of cation types on the steel corrosion inhibition behavior of CLDH in saturated calcium hydroxide solution using equilibrium isotherms of Cl− uptake, the electrochemical method, X-ray diffraction (XRD), Fourier-transform infrared (FTIR), and scanning electron microscopy (SEM) techniques. The results show that the corrosion inhibition of the CLDH is affected by the cation types in the following order: Ca2+>Mg2+>K+≈Na+·Na+ and K+ increase the pH of the solution and decrease the corrosion inhibition of CLDH. The addition of Mg2+ can promote the reconstruction of Mg-Al-Zn-Cl hydrotalcite. The addition of Ca2+ can promote the formation of new Ca-Al layered double hydroxide (Ca-Al-LDH) and improve the corrosion inhibition. [ABSTRACT FROM AUTHOR]