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To promote the resource utilization of steel slag and improve the production process of steel slag in steelmaking plants, this research studied the characteristics of three different processed steel slags from four steelmaking plants. The physical and mechanical characteristics and volume stability of steel slags were analyzed through density, water absorption, and expansion tests. The main mineral phases, morphological characteristics, and thermal stability of the original steel slag and the steel slag after the expansion test are analyzed with X-ray diffractometer (XRD), scanning electron microscope (SEM), and thermogravimetric analysis (TG) tests. The results show that the composition of steel slag produced by different processes is similar. The main active substances of other processed steel slags are dicalcium silicate (C2S), tricalcium silicate (C3S), CaO, and MgO. After the expansion test, the main chemical products of steel slag are CaCO3, MgCO3, and calcium silicate hydrate (C-S-H). Noticeable mineral crystals appeared on the surface of the steel slag after the expansion test, presenting tetrahedral or cigar-like protrusions. The drum slag had the highest density and water stability. The drum slag had the lowest porosity and the densest microstructure surface, compared with steel slags that other methods produce. The thermal stability of steel slag treated by the hot splashing method was relatively higher than that of steel slag treated by the other two methods. [ABSTRACT FROM AUTHOR]

The harsh service environment of aeroengine hot-end components requires superalloys possessing excellent antioxidant properties. This study investigated the effect of pre-strain on the oxidation behavior of polycrystalline Ni3Al-based superalloys. The growth behaviors of oxidation products were analyzed by scanning electron microscope, transmission electron microscope, X-ray Photoelectron Spectroscopy and Raman spectroscopy. The results indicated that the 5% pre-strained alloys exhibited lower mass gain, shallower oxidation depth and more compact oxide film structures compared to the original alloy. This is mainly attributed to the formation of rapid diffusion paths for Al atoms diffusing to the surface under 5% pre-strain, which promotes the faster formation of protective Al2O3 film while continuing to increase the pre-strain to 25% results in less protective transient oxidation behavior being aggravated due to the increase in dislocation density within the alloy, which prevents the timely formation of the protective Al2O3 film, resulting in uneven oxidation behavior on the alloy. [ABSTRACT FROM AUTHOR]

It has been recently demonstrated that laser micromachining of magnetoactive elastomers is a very convenient method for fabricating dynamic surface microstructures with magnetically tunable properties, such as wettability and surface reflectivity. In this study, we investigate the impact of the micromachining process on the fabricated material's structural properties and its chemical composition. By employing scanning electron microscopy, we investigate changes in size distribution and spatial arrangement of carbonyl iron microparticles dispersed in the polydimethylsiloxane (PDMS) matrix as a function of laser irradiation. Based on the images obtained by a low vacuum secondary electron detector, we analyze modifications of the surface topography. The results show that most profound modifications occur during the low-exposure (8 J/cm2) treatment of the surface with the laser beam. Our findings provide important insights for developing theoretical models of functional properties of laser-sculptured microstructures from magnetoactive elastomers. [ABSTRACT FROM AUTHOR]

Manganese slag (MS) containing a certain amount of active hydration substances may be used as a kind of cementitious material. In the present study, we measured the mass, the relative dynamic modulus of elasticity (RDME), and the flexural and compressive strengths of MS high-performance concrete (MS-HPC) with added basalt fibers exposed to NaCl freeze–thaw cycles (N-FCs), NaCl dry–wet alternations (N-DAs), and Na2SO4 dry–wet alternations (NS-DAs). Scanning electron microscope energy-dispersive spectrometer (SEM-EDS) spectra, thermogravimetric analysis (TG) curves, and X-ray diffraction spectroscopy (XRD) curves were obtained. The mass ratio of MS ranged from 0% to 40%. The volume ratio of basalt fibers varied from 0% to 2%. We found that, as a result of salt action, the mass loss rate (MLR) exhibited linear functions which were inversely correlated with the mass ratio of MS and the volume ratio of basalt fibers. After salt action, MLR increased by rates of 0~56.3%, but this increase was attenuated by the addition of MS and basalt fibers. Corresponding increases in RDME exhibited a linear function which was positively correlated with MS mass ratios in a range of 0~55.1%. The addition of MS and basalt fibers also led to decreased attenuation of mechanical strength, while the addition of MS led to increased levels of flocculent hydration products and the elements Mn, Mg, and Fe. CaClOH and CaSO4 crystals were observed in XRD curves after N-DA and NS-DA actions, respectively. Finally, the addition of MS resulted in increased variation in TG values. However, the opposite result was obtained when dry–wet actions were exerted. [ABSTRACT FROM AUTHOR]

Although cemented soil as a subgrade fill material can meet certain performance requirements, it is susceptible to capillary erosion caused by groundwater. In order to eliminate the hazards caused by capillary water rise and to summarize the relevant laws of water transport properties, graphene oxide (GO) was used to improve cemented soil. This paper conducted capillary water absorption tests, unconfined compressive strength (UCS) tests, softening coefficient tests, and scanning electron microscope (SEM) tests on cemented soil using various contents of GO. The results showed that the capillary water absorption capacity and capillary water absorption rate exhibited a decreasing and then increasing trend with increasing GO content, while the UCS demonstrated an increasing and then decreasing trend. The improvement effect is most obvious when the content is 0.09%. At this content, the capillary absorption and capillary water absorption rate were reduced by 25.8% and 33.9%, respectively, and the UCS at 7d, 14d, and 28d was increased by 70.32%, 57.94%, and 61.97%, respectively. SEM testing results demonstrated that GO reduces the apparent void ratio of cemented soil by stimulating cement hydration and promoting ion exchange, thereby optimizing the microstructure and improving water resistance and mechanical properties. This research serves as a foundation for further investigating water migration and the appropriate treatment of GO-modified cemented soil subgrade. [ABSTRACT FROM AUTHOR]

Dressings with multiple functional performances (such as hemostasis, promoting regeneration, analgesia, and anti-inflammatory effects) are highly desired in orthopedic surgery. Herein, several new kinds of medicated nanofibers loaded with several active ingredients for providing multiple functions were prepared using the modified coaxial electrospinning processes. With an electrospinnable solution composed of polycaprolactone and fenoprofen as the core working fluid, several different types of unspinnable fluids (including pure solvent, nanosuspension containing tranexamic acid and hydroxyapatite, and dilute polymeric solution comprising tranexamic acid, hydroxyapatite, and polyvinylpyrrolidone) were explored to implement the modified coaxial processes for creating the multifunctional nanofibers. Their morphologies and inner structures were assessed through scanning and transmission electron microscopes, which all showed a linear format without the discerned beads or spindles and a diameter smaller than 1.0 μm, and some of them had incomplete core–shell nanostructures, represented by the symbol @. Additionally, strange details about the sheaths' topographies were observed, which included cracks, adhesions, and embedded nanoparticles. XRD and FTIR verified that the drugs tranexamic acid and fenoprofen presented in the nanofibers in an amorphous state, which resulted from the fine compatibility among the involved components. All the prepared samples were demonstrated to have a fine hydrophilic property and exhibited a lower water contact angle smaller than 40° in 300 ms. In vitro dissolution tests indicated that fenoprofen was released in a sustained manner over 6 h through a typical Fickian diffusion mechanism. Hemostatic tests verified that the intentional distribution of tranexamic acid on the shell sections was able to endow a rapid hemostatic effect within 60 s. [ABSTRACT FROM AUTHOR]

This paper describes the methodology of combining experimental measurements with mathematical–physics analyses in the investigation of flow in the aperture and nozzle. The aperture and nozzle separate the differentially pumped chamber from the specimen chamber in an environmental scanning electron microscope (ESEM). Experimental measurements are provided by temperature and pressure sensors that meet the demanding conditions of cryogenic temperature zones and low pressures. This aperture maintains the required pressure difference between the chambers. Since it separates the large pressure gradient, critical flow occurs on it and supersonic gas flow with the characteristic properties of critical flow in the state variables occurs behind it. As a primary electron beam passes through the differential pumped chamber and the given aperture, the aperture is equipped with a nozzle. The shape of the nozzle strongly influences the character of the supersonic flow. The course of state variables is also strongly influenced by this shape; thus, it affects the number of collisions the primary beam's electrons have with gas molecules, and so the resulting image. This paper describes experimental measurements made using sensors under laboratory conditions in a specially created experimental chamber. Then, validation using mathematical–physical analysis in the Ansys Fluent system is described. [ABSTRACT FROM AUTHOR]

In this work, UV-Vis spectrophotometry, High Resolution Scanning Transmission Electron Microscopes and selected experimental conditions were used to screen the colloidal system. The obtained results complement the established knowledge regarding the mechanism of nanoparticle formation. The process of gold nanoparticles formation involves a two-step reduction of Au ions to Au(0); atom association and metastable cluster formation; autocatalytic cluster growth; ultra-small particle formation (1–2 nm, in diameter); particle growth and larger particles formation; and further autocatalytic crystal growth (D > 100 nm). As a reductant of Au(III) ions, a cinnamon extract was used. It was confirmed that eugenol as one of the cinnamon extract compounds is responsible for fast Au(III) ion reduction, whereas cinnamaldehyde acts as a gold-particle stabilizer. Spectrophotometry studies were carried out to track kinetic traces of gold nanoparticle (D > 2 nm) formation in the colloidal solution. Using the Watzky—Finke model, the rate constants of nucleation and autocatalytic growth were determined. Moreover, the values of energy, enthalpy and entropy of activation for stages related to the process of nanoparticle formation (Index 1 relates to nucleation, and Index 2 relates to the growth) were determined and found to be E1 = 70.6 kJ, E2 = 19.6 kJ, ΔH1 = 67.9 kJ/mol, ΔH2 = 17 kJ/mol, ΔS1 = −76.2 J/(K·mol), ΔS2 = −204.2 J/(K·mol), respectively. In this work the limitation of each technique (spectrophotometry vs. HRSTEM) as a complex tool to understand the dynamic of the colloidal system was discussed. [ABSTRACT FROM AUTHOR]

Bi(2/3)‐xSmxCu3Ti4O12 (BSCTO x = 0.05, 0.10, and 0.20) ceramics are synthesized using semi‐wet technique and an extensive investigation into their structural, morphological, and elemental properties, alongside dielectric and impedance behaviors, is meticulously carried out. X‐ray powder diffraction analysis unequivocally confirmed the formation of a monophasic BCTO cubic phase without any discernible secondary phases. and the crystallite size of the BSCTO ceramic, obtained by X‐ray diffraction using Debye Scherrer formula, range from 62 to 81 nm. Rietveld analysis reveals that ceramics have a body centered cubic structure with space group Im‐3. The Scanning electron microscope image displays the dense microstructure of the ceramics, while EDX analysis unveils the elemental composition of resulting products. Doping with Sm3+ induced a notable reduction in grain size, as observed through Scanning electron microscope and Atomic Force Microscope analyses, indicating Sm3+ hindered grain growth during sintering, potentially resulting in reduced dielectric constant (ε′). Dielectric constant and dielectric loss of the composition (x = 0.2) are found to be ≈$ \approx $152 and 0.04, respectively at room temperature (1 kHz). Impedance characteristics revealed a substantial increase in grain boundary resistance, leading to improved dielectric loss. The AC conductivity of BSCTO ceramics exhibited a frequency‐dependent increase satisfying to Johncher's power law. [ABSTRACT FROM AUTHOR]

To expand the market capacity of p‐diethylbenzene (PDEB), core‐shell zeolite (TS‐1@MCM‐48) is designed as a catalyst for PDEB oxidation. TS‐1@MCM‐48 catalyst is synthesized by in‐situ crystallization method and characterized by X‐ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS), N2 adsorption‐desorption, in‐situ electron paramagnetic resonance (EPR) and 29Si nuclear magnetic resonance (29Si MAS‐NMR). Oxidation of PDEB by H2O2 was investigated systematically in liquid phase. The conversion of PDEB over TS‐1@MCM‐48 was 28.1 % and the total selectivity was 72.6 %, where the selectivity of EAP (p‐ethylacetophenone) and EPEA (4‐ethyl‐α‐methylbenzyl alcohol) was 28.6 % and 44.0 %, respectively. Compared with TS‐1 and MCM‐48 zeolite, the conversion rate of reactants and the selectivity of products have been significantly improved. The catalytic performance of TS‐1@MCM‐48 is derived from its well‐crystallized microporous core and mesoporous shell with regular channels, which make active sites of TS‐1 zeolite in the catalyst be fully utilized and mass transfer resistance be largely reduced. Further through theoretical calculation, we propose that the oxidation of PDEB is the result of the combination and mutual transformation of free radical process and carbocation process. Core‐shell structure ensures the conversion rate of raw materials and improves the selectivity of products. [ABSTRACT FROM AUTHOR]

DYT1 dystonia is associated with decreased striatal dopamine release. In this study, we examined the possibility that ultrastructural changes of nigrostriatal dopamine terminals could contribute to this neurochemical imbalance using a serial block face/scanning electron microscope (SBF/SEM) and three‐dimensional reconstruction to analyse striatal tyrosine hydroxylase‐immunoreactive (TH‐IR) terminals and their synapses in a DYT1(ΔE) knockin (DYT1‐KI) mouse model of DYT1 dystonia. Furthermore, to study possible changes in vesicle packaging capacity of dopamine, we used transmission electron microscopy to assess the synaptic vesicle size in striatal dopamine terminals. Quantitative comparative analysis of 80 fully reconstructed TH‐IR terminals in the WT and DYT1‐KI mice indicate (1) no significant difference in the volume of TH‐IR terminals; (2) no major change in the proportion of axo‐spinous versus axo‐dendritic synapses; (3) no significant change in the post‐synaptic density (PSD) area of axo‐dendritic synapses, while the PSDs of axo‐spinous synapses were significantly smaller in DYT1‐KI mice; (4) no significant change in the contact area between TH‐IR terminals and dendritic shafts or spines, while the ratio of PSD area/contact area decreased significantly for both axo‐dendritic and axo‐spinous synapses in DYT1‐KI mice; (5) no significant difference in the mitochondria volume; and (6) no significant difference in the synaptic vesicle area between the two groups. Altogether, these findings suggest that abnormal morphometric changes of nigrostriatal dopamine terminals and their post‐synaptic targets are unlikely to be a major source of reduced striatal dopamine release in DYT1 dystonia. [ABSTRACT FROM AUTHOR]

In this article, the effect of Ce element on the microstructure and mechanical properties was studied by Ce addition to the hot‐formed steel. Scanning electron microscope and energy dispersive spectrometer (SEM‐EDS) was used to analyze the improvement effect of Ce on inclusions and the effect of inclusions on fracture behavior; Electron back scattering diffractometer (EBSD) was used to analyze the refinement and strengthening effect of Ce on martensitic grains; transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM) was used to analyze the microstructure strengthening effect and microalloying effect of solid solution Ce in hot‐formed steel. Through a systematic analysis of mechanical properties and microstructure, the mechanism of Ce enhances the strength and elongation of hot‐formed steel was clarified. Besides, this work provides a research basis for further improving the safety and machinability of hot‐formed steel. [ABSTRACT FROM AUTHOR]

The effects of Ce treatment on the inclusion evolution and impact toughness of as‐cast transformation‐induced plasticity (TRIP) steel are systematically investigated by scanning electron microscope (SEM) and impact toughness testing. The results reveal that in Fe‐2Mn‐1.5Al‐1Si‐0.2C steel without Ce, the primary inclusions consist of AlN, MnS, and Al2O3. After Ce addition, the inclusions evolve into Ce‐Al‐O, Ce2O2S, CeS, and Ce2O3 inclusions. The evolution of inclusions exhibits an initial reduction in both quantity and size with increasing Ce content, followed by a subsequent increase. In cases of excessive Ce content, there is an observable rise in the overall inclusion count, marked by the emergence of CeAs, CeP, and CeC2 inclusions. The segregation model suggests that P‐containing inclusions predominantly precipitate in the late solidification process, while As‐ and C‐containing inclusions form during the solid phase. When the Ce content reaches 0.0075 wt%, the minimum values of the number density and average diameter are 96.7 mm−2 and 1.6 μm, respectively. Furthermore, the influence of the size, morphology, quantity, and type of inclusions on the impact toughness are analyzed. The highest recorded impact energy is 6.8 J with a Ce content of 0.0075 wt%. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs), specifically those involving V and Ti, possess fascinating material properties, making them interesting candidates for scientific studies. The existing growth methods of these materials are typically limited by scalability – either low yield or high cost. Here, we propose an alternative 2-step method valid for scalable production. In the first step, precursor films of Ti / V are deposited using magnetron sputtering, followed by the second step of selenization of these samples using elemental Se in a vacuum-sealed quartz ampoule for conversion to their respective diselenide material. Synthesized films are char-acterised using scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and X-ray photoelectron (XPS). The method demonstrated here can be used to increase the active surface area of TiSe2 and VSe2 for their potential catalytic and HER applications using nanostructured substrates, while also providing an opportunity for scalable synthesis of films that can be extended to synthesize other TMDs as well. [ABSTRACT FROM AUTHOR]

Warm mix asphalt mixtures became attractive paving mixes by reducing the production temperature to around 25–40 °C as compared to that of conventional hot mix asphalt (HMA). This study aims to evaluate the warm mix asphalt (WMA) using wax-based additives by incorporating two types of industrial wastes. The potential application of low calcium fly ash (FA), i.e. class F type and marble dust (MD), has been evaluated by varying different percentage. The cylindrical samples were prepared and assessed for moisture susceptibility by being subjected to Marshall stability, retained Marshall stability (RMS), indirect tensile strength (ITS) and tensile strength ratio (TSR) tests. Furthermore, the samples were also evaluated for finding the refusal density, Cantabro loss and the rutting performance. A scanning electron microscope (SEM) was also used to evaluate the size and microstructure of the filler particles. The results revealed that the inclusion of fillers into mixes had significant improvement in the mechanical properties and lowered the rutting value with FA and MD addition. The warm mix additive and fillers used were also useful in reducing the binder content of the mixes. The mixing temperature was found to be in the range of 120–130 °C using the warm mix additive. The optimum usage of FA and MD can be up to 5% based on the evaluation. The statistical results reported that there was a significant difference between FA-based and MD-based WMA. [ABSTRACT FROM AUTHOR]

The lack of a code for preparing one-part geopolymer concrete (GPC) is one of the major obstacles to its wide use. This study adopted one of the most common methods for preparing ordinary concrete, the ACI method, taking into account the most important variables affecting this method and then modified it to suit one-part GPC. Three different sizes of aggregates and four water-to-binder ratios (W/B) were used in preparing the concrete mixtures in this study. In addition, three different proportions of sodium metasilicate were used as the activator, which ultimately resulted in a total of 36 mix designs. Specimens were subjected to various tests, including setting time, workability, and compressive strength. In addition, the material's behaviour was studied using X-ray diffraction and scanning electron microscope. The results indicate that the ACI method is generally applicable for designing geopolymer concrete mixtures with minor adjustments. Consequently, the table used for predicting concrete strength based on a specific water/cement ratio has been replaced with relevant figures that depict the relationship between compressive strength and the water-to-binder ratio. In addition, a step-by-step flowchart has been presented that explains how to design one-part geopolymer concrete. Conducted experiments indicated that the properties of geopolymer concrete are greatly affected by the ratio of W/B and the size of aggregate used in preparing the concrete mixture. Furthermore, the quantity of activators has significant effects on concrete's workability and compressive strength. Results of the experiment suggest that one-part GPC can provide greater compressive strength than ordinary concrete. [ABSTRACT FROM AUTHOR]

In the context of sustainable development and environmental protection, the current study aims to give scientific evidence of the feasibility of replacing natural siliceous sand with crushed limestone sand in concrete. It assesses the effect of this replacement by comparing concretes without natural sand to a reference mix incorporating natural sand. For fixed water-to-cement ratio, cement content, and coarse aggregates proportions, and for different dosages of admixture to reach the same slump, the results proved that the concrete containing natural sand required more admixture to reach the same slump value as the crushed limestone sand concrete. For the same workability, the compressive and flexural strengths were not affected by the total replacement of natural sand with crushed sand. The three types of concrete fell within the same range of durability even though scanning electron microscope (SEM) analysis seemed to reveal a better paste-fine aggregate interface for crushed sand concrete. The concrete properties could be maintained when using crushed limestone sand conforming to the standard grading requirements, as the only fine aggregate in concrete. [ABSTRACT FROM AUTHOR]

Recently, nanoparticle (NP)-based drugs have been developed to increase the efficiency of existing cancer treatment approaches; however, how NPs interact with cellular systems is still uncertain. In this study, we have examined the ability of Se–FA NPs to enhance the chemotherapeutic effect of 5-fluorouracil (5-FU) in human AGS gastric cancer cells as well as their ability alone and in combination with 5-FU to modulate autophagy. The prepared NPs were characterized using Fourier-transform infrared spectroscopy, dynamic light scattering, and scanning electron microscope. Cytotoxicity and autophagy-modulating activity of NPs were determined using MTT, q-PCR, and western blot methods. The size and surface charge of NPs were determined to be ~ 90.4 nm and − 53.8 mV, respectively. Se–FA NPs enhance the cytotoxicity of 5-FU (up to 4.1-fold) and consequently inhibit autophagy flux in AGS cells. These findings confirm the therapeutic potential of combining Se–FA NPs with 5-FU in an in vitro gastric cancer model and may suggest an approach to overcome chemotherapy resistance in cancer. [ABSTRACT FROM AUTHOR]

In this study, La2Zr2O7, Yb2O3 and Gd2O3-doped La 1. 4 (Gd, Yb) 0. 6 Zr2O7 thermal barrier coatings have been manufactured from the crystalline and amorphous feedstock by plasma spraying. The thickness of the bond coat is 100±25 μ m and the thickness of the top coat is 250±25 μ m. Thermal shock tests were carried out in furnace temperature of 1200∘C. The thermal shock tests indicate that lifetime of the La 1. 4 Gd 0. 6 Zr2O7 coating has 55 cycles which is the highest thermal shock lifetime compared to other coatings in this study. The type of feedstock, amorphous or crystalline, strongly affects the thermal shock lifetime of La2Zr2O7 coatings. Coating damage after thermal shock tests was investigated using scanning electron microscope to observe the microstructure and X-ray diffraction techniques to analyze the phase composition. The failure of coatings is mainly in consequence of the accumulation of stress between bond coat–ceramic coat interface due to thermal expansion coefficient differences and thermally grown oxide layer formation during thermal shock cycling tests. [ABSTRACT FROM AUTHOR]

In this work, the Metal Inert Gas (MIG) welding process is used for depositing the Inconel 718 over the base substrate of Stainless steel 321. The optimal welding conditions like 50% overlap, Direct Current (DC) plus mode with a pulse on time (1–5 s), frequency (0.25–1 Hz), peak current (120 A), base currents (60% of peak current), and speed (150–350 mm/min) are used for the successful hard-facing. The quality of the hard-facing is analyzed by conducting microstructural studies, tensile tests, microhardness, wear behavior, and electrochemical studies. Post-processing for wear and electrochemical studies is done by Scanning Electron Microscope SEM–EDX analysis. Microstructural studies revealed the presence of columnar dendrites and equiaxed at the top of the hard-faced layer. Hard-faced layer depicts the highest ultimate tensile strength of 772 N/mm2 with an elongation of 31.50% due to the support of Nickel components. The presence of the voids and dimples is identified from the SEM fractography. The maximum hardness value of 212 HV 0. 5 is measured at the top of the hard face layer. The microhardness of the hard-faced layer increased by 17.77% higher than its base substrate. Because of the hard precipitates and higher microhardness made by the weld thermal cycle, the hard-face layer showed maximum Co-efficient of Friction (CoF) of 0.540. Debris and grooves are found with the SEM examination of the wear specimens. Higher impedance offers better corrosion resistance to the hard-faced layer Inconel 718. The EDX analysis confirms the presence of Chromium, Molybdenum, and Niobium contents at the hard-faced layer. These elements silently support better corrosion resistance compared to the base substrate of Stainless steel 321. [ABSTRACT FROM AUTHOR]

In the present study, the flexural, morphological, and shape memory properties of polylactic acid (PLA) matrix sandwiched with polyvinylidene difluoride (PVDF) Nanofibers (NFs) interleave composite structures have been investigated for applications of 4D printing such as smart grippers, and smart actuators. Firstly, an electrospinning process was carried out to form a PVDF NFs mat (thickness: 0.10–0.20 mm) under a flow rate of 3 µL/sec, an applied voltage of 12 kV, and a TCD of 100 mm. Further, the PVDF NFs mat was deposited in between the PLA layers, primed through fused filament fabrication (FFF) based 3D printing to manufacture the PLA-PVDF NFs-PLA based structures. In the next stage, the flexural properties were investigated for manufactured composite structures. The results highlight that the flexural strength of the composites was enhanced by 6.47% as compared to PLA. Results of the study are supported by a scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), V-I, V-R, and shape memory analysis. The finding of the study suggests that composite structures primed by higher mat thickness and zig-zag infill pattern have resulted in higher electrical resistance and better shape memory effect. However, increasing the voltage in the composite structure having higher mat thickness with a zig-zag fill pattern has resulted in a higher resistance drop. [ABSTRACT FROM AUTHOR]

Friction Stir Welding is a process that has led to increasing usage of aluminum and its alloys in different industries, since it is an autogenous and a solid-state welding process. The work developed in this paper was focused on the analysis of the mechanical behavior of AA7075-T651 friction stir butt welded joints, of 4 mm of thickness, under different loading and temperature conditions. A selection process was applied to assure the appropriate welding parameters. The welds from which the investigated specimens were manufactured from were submitted to nondestructive testing to assess the presence of welding defects. Fatigue tests were carried out, under a constant amplitude loading regime, at stress ratios of 0.05 and 0.5 and at temperatures of 23 °C and 150 °C. The results obtained by the fatigue tests point to a higher fatigue life of the specimens when the highest stress ratio, R = 0.5, was used (for the maximum stress applied), for both loading temperatures. For the stress range, the contrary was found to be true. Room temperature was also found to result in a significantly better fatigue performance. A Scanning Electron Microscope was used to characterize the fatigue fracture surfaces. [ABSTRACT FROM AUTHOR]

A group of aquatic Coleoptera specimens was collected from Güvenç Village in the Kahramankazan region of Ankara. Among these specimens was Dryops rufipes (Krynicki, 1832) (Coleoptera: Dryopidae), which is recorded from the Middle Anatolian Region of Turkey for the first time. The egg morphology of D. rufipes is described based on light and scanning electron microscope micrographs. Copulation and oviposition are described. [ABSTRACT FROM AUTHOR]

The organic–inorganic hybrid composite materials, polybithiophene and Cadmium Sulphide have been successfully synthesized by electrochemical method onto the ITO substrates. The obtained hybrids were characterized by techniques like Scanning electron microscope (SEM), UV–Vis photo spectrometer and X-ray diffraction (XRD) to examine the phase purity and crystal structure. Electrical characteristics of the hybrid composite have been investigated with photoelectrochemical (PEC) and Mott–Schottky (MS) analysis in an electrolyte solution. Mott-schottky and photoelectrochemical studies indicate that the conducting polymer polybithiophene. (PBTh) as p-type semiconductor and cadmium bands (CdS) thin films as n-type semiconductor. As results, X-ray diffraction patterns show that the polybithiophene film is amorphous whereas the cadmium bands is hexagonal wurtzite structure. The optical band gap energies of p-PBTh and n-CdS-PBTh film are 2 and 1.78 eV, respectively. The Scanning electron microscope also revealed that cadmium bands plays an important role to strengthen the structural, morphological and optical properties of deposited thin films. The current–voltage (I–V) confirms the formation of junction in p-PBTh/n- CdS-PBTh arrays and best results have been obtained, the short-circuit current (Isc = 10.38 (μA cm−2), the open circuit voltage (Vco = 1.96 V), the fill factor (FF = 24%) and conversion efficiency (ɳ = 0.54%), the various results obtained are attractive and suitable for photovoltaic applications. [ABSTRACT FROM AUTHOR]

Solvent evaporation was used to create a novel organic Schiff-based optical crystal of Benzimidazolium gallate (BGA). The size of unit cells was determined using X-ray diffraction analysis. Fourier transform infra-red spectrum analysis revealed chemical bonds' vibrational behavior and their functional groups' existence. Optical transparency and optical bandgap (3.66 eV) were observed by the UV–visible-near infrared spectral analysis. Differential scanning calorimetry curves show that decomposition is exhibited at 215 °C. Dielectric experiments on the BGA crystal were performed at ambient temperature. High-resolution scanning electron microscope analysis shows the crystal's nature and surface shape. The Z-scan process explored the BGA crystal's nonlinearity, and the crystal is suitable for photonic, optoelectronic, and optical-limiting applications. [ABSTRACT FROM AUTHOR]

In the current study, a novel electrochemical sensor has been developed for levofloxacin detection, by coating an Indium tin oxide (ITO) modified electrode with a thin film of Cu-nanoplatelets, WO3 quantum dots coupled to the g-C3N4 nanosheets. The prepared electrode was characterized using various analytical tools, including powder X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM) and Fourier-Transform Infrared spectroscopy (FT-IR). The electrochemical properties of levofloxacin (LEVO) were determined by performing cyclic voltammetry (CV) and amperometric tests. The hybrid electrode exhibits a well-defined peak around 1.2 V during the anodic potential scan, which was attributed to the (LEVO) oxidation process. The measured ultrahigh sensitivity is 0.786 µA µM−1 cm−2 for a linear range of 0–70 µM in the low concentration zone and 0.312 µA µM−1 cm−2 for a linear range of 120–870 µM in the high concentration zone. A good linear correlation between the peak current and LEVO concentration in the range of 0 to 70 µM was obtained through detection and quantification limits of 0.1 µM and 0.3 µM, respectively.The WO3/g-C3N4/Cu nanoparticles that modified the ITO electrode reveals high stability, reproducibility, and repeatability, as well as selectivity for LEVO in real water samples. Analyses were also conducted on the LEVO detection in the presence of interfering substances.As far as this paper is concerned, this is the first time that a ternary nanocomposite WO3/g-C3N4/Cu has been used to detect LEVO at low and high concentrations. Application of ITO/WO3/g-C3N4/Cu as an electrochemical sensor for LEVO [ABSTRACT FROM AUTHOR]

Cement-based cementing materials have some disadvantages, such as high brittleness and poor mechanical properties. In the long-term production process of oil and gas wells, it is easy to damage, resulting in annulus pressure and interlayer channeling. However, curable resin-based cementing materials have the advantages of good toughness, high strength, and low elastic modulus, and have the potential as cementing materials. A water-based epoxy resin cementing fluid system suitable for cementing was obtained in this article, which has good toughness and high strength, and can directly replace cement slurry for cementing. When the temperature was 50 °C and 70 °C, the fluidity of water-based epoxy resin cementing fluid system was greater than 18 cm, and the thickening time was 74 minute and 128 minute, respectively. The 28 day compressive strength of the resin cured at 70 °C increased by 276.3% and the tensile strength increased by 117.9% compared with the blank cement paste. Scanning electron microscope test indicated that the matrix of water-based epoxy resin is denser than that of blank cement paste. Fourier transform infrared spectrometer and X-ray diffraction analyses demonstrate that the cured epoxy resin products are not affected by curing age. According to the thermogravimetric results, epoxy resin can be used in high temperature deep well. On the whole, replacing cement with water-based epoxy resin cementing fluid can improve the cementing quality, which has broad application value. [ABSTRACT FROM AUTHOR]

The new period of science and technology implies control over the size and shape of materials. In determining the properties and potential application of materials the morphology variation plays an important role. The present study focuses on the fabrication of calcium oxalate (CaC2O4) in a nano range having uniform and novel particle morphology. The powder materials having monodispersed particles of plate-like and donut-shaped morphologies were successfully synthesized by a controlled precipitation method under extensively optimized experimental parameters. The morphology of the as-prepared uniform fine particle systems was studied by scanning electron microscope and the mechanical functional surface groups and crystallinity of the test material were examined by Fourier transform infrared spectroscopy (FT-IR) and (XRD) X-ray diffraction analysis, respectively. The effect of different parameters on calcium oxalate particle morphology was also investigated. The observed results explored a significant effect of technological parameters on particle size, shape, and uniformity. Therefore, monodispersed unique particle systems of calcium oxalate were synthesized under a narrow set of experimental conditions through a reproducible recipe protocol. [ABSTRACT FROM AUTHOR]

Zeolitic Imidazole Frameworks (ZIFs) are prospective porous materials as catalyst support due to their relatively large surface area, and tunability in size, structure, and porosity. Recent studies have also shown that ZIF is the best candidate for various catalytic redox reactions such as the oxidation of benzyl aromatic hydrocarbons. In this study, the synthesized Pt catalyst supported on Co-ZIF was varied by the organic ligands: imidazole, benzimidazole, and 1- (3-aminopropyl) imidazole, then followed by impregnation of Pt precursor. The catalysts were characterized its physical and chemicals properties such as Fourier Transform Infrared (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Brunauer Emmet Teller (BET), Temperature-Programmed Desorption (NH3-TPD and CO2-TPD). The prepared catalysts were evaluated for catalytic hydrocracking and hydroisomerization of n-hexadecane in a 100 ml-batch reactor. GC-MS analysis presented that the Pt/ZIF catalyst with imidazole ligands has better performance than others. Hence, the optimization of n-Hexadecane conversion was carried out by the Pt/ZIF-imidazole catalyst varying the amount of metal loading, time and temperature reaction. The results showed that the reaction temperature of 350 °C using 20 bar H2 for 4 h and the addition of 15 wt% Pt successfully achieved 90.77% conversion and produced the highest yield of isomers and alkanes, 4.04% and 35.75%, respectively. [ABSTRACT FROM AUTHOR]

Research has been carried out on making biodiesel from palm oil using natural zeolite catalysts impregnated with metal oxides such as zinc oxide and titanium oxide. This research aims to produce biodiesel using natural zeolite and ZnO-TiO2/NZ catalysts. The catalysts were analyzed using X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscope (SEM), and Brunauer-Emmet-Teller (BET). The catalyst was tested in the transesterification reaction to produce biodiesel. The oil and methanol mole ratio varied from 1:15, 1:18, and 1:20. In addition, the biodiesel product was analyzed using Gas Chromatography-Mass Spectroscopy (GC-MS). The results showed the optimum condition for converting triglycerides to 1:18 variation of oil:methanol mole ratio was 60.53% using a ZnO-TiO2/NZ catalyst. The ZnO-TiO2/NZ catalyst is very promising for use as a catalyst for converting palm oils into biodiesel. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing effectively enhances production in the unconventional oil and gas industry. As we all know, proppant plays a vital role in the hydraulic fracturing. In this paper, the effects of proppant type, particle size, concentration, closure pressure, and other factors are studied by laboratory experiments. Based on the actual triaxial simulation device (TSD), quartz sand, ceramic, and coated sand are used as proppant, while sandstone, coal rock, shale, and granite are selected as the stone slate to experiment. The surface of the proppant was imaged by a surface profiler (SP) and scanning electron microscope (SEM) to compare the microscopic surface characteristics before and after the experiment. The particle size macroscopic distribution was measured by Mastersizer 2000. The results and innovation are as follows: This paper investigates the proppant crushing for hydraulic fracturing and provides an alternative evaluation method for proppant selection. The crushing laws of proppant under different pressures and stone slate are compared by using the experimental device. It is reliable for quartz sand to replace ceramic in deep layer of the field application. It also overturns the previous thinking. We believe this found holds the key toward systematically optimizing the development of unconventional reservoirs. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of incorporating nanoparticles on the energy absorption properties of nanocomposites using low-velocity impact (LVI) testing and molecular modeling. Various types of thermoset polymer-based nanocomposites reinforced with carbon nanotubes (CNTs) and alumina were analyzed, and the effect of adding two types of nanofillers and microfiber as a filler material was investigated. The results show that the addition of nanoparticles significantly improved the elastic energy absorption properties of the nanocomposites at the atomic level. The LVI tests demonstrated that adding both types of nanoparticles, along with microfiber, significantly enhanced the energy absorption capacity of the four-phase composite under practical conditions. The scanning electron microscope (SEM) analyses revealed the morphology behavior of the nanoparticles. Incorporating both types of nanoparticles simultaneously with the polymer and fibers increased the elastic modulus by up to 163 %. These findings have significant implications for designing structures with energy-absorbing materials to reduce sports-related injuries. The use of nanocomposites with enhanced energy absorption properties can help to improve the performance of energy-absorbing structures and reduce the risk of sports-related injuries. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) multiferroic composites are more promising candidates for low-power consumption devices, next-generation spintronic devices, and multistate memory devices since they exhibit significantly higher Magnetoelectric interaction over single-phase multiferroics. In this regard magnetic behaviour, dielectric, and magnetoelectric characteristics of a novel Pb-free (1-x) Na 0.5 Bi 0.5 TiO 3 -(x) Ni 0.5 Co 0.5 Fe 2 O 4 , (x = 0, 0.2, 0.4, 0.6, 0.8 & 1) particulate composites were explored. Solid-state synthesis was adopted to prepare the single-phase Na 0.5 Bi 0.5 TiO 3 (NBT), Ni 0.5 Co 0.5 Fe 2 O 4 (NCFO), and their composites. The presence of rhombohedral NBT and cubic inverse spinel NCFO in the composites were confirmed with X-ray diffraction (XRD) patterns. Microstrain (ε) induced in the prepared samples was estimated by using the Williamson-Hall (W-H) method. The piezoelectric NBT phase shows the tensile strain and the ferromagnetic NCFO shows the comprehensive strain. Among all the composites 0.8NBT-0.2NCFO shows a higher strain value of 0.012%, and the decrement in the strain values was observed upon increases in ferrite concentration. Backscattered scanning electron microscope (BS-SEM) images revealed the existence of highly dense uniformly distributed elements and Energy dispersive spectroscopy (EDS) confirmed the existing elements in the composites. UV–vis absorbance spectra disclosed a rise in energy gap values from 1.14 eV to 3.0 eV with increasing NBT percentage. Variations of dielectric permittivity and dielectric loss with respect to AC frequency were studied at room temperature (RT), and the 0.2NBT-0.8NCFO sample shows a high dielectric permittivity of 8500 at ∼100Hz. M − H (Magnetization-Magnetic field) hysteresis loops demonstrate the pure ferrite phase has a coercive field (H c) = 578 Oe, remnant magnetization (M r) = 21.43 emu/g and saturation magnetization (M s) = 71.29 emu/g. The M s and M r values in the composites are enhanced with increasing ferrite percentage. Studies on ME behaviour of (1-x) NBT-(x) NCFO, (x = 0.2,0.4,0.6 & 0.8) show the coupling effect between both the phases at room temperature and the highest coupling coefficient value 3.16mV/Cm. Oe was observed for the 0.8NBT-0.2NCFO further the reasons and mechanisms are discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: Au stud bump bonding technology is an effective means to realize heterogeneous integration of commercial chips in the 2.5D electronic packaging. The purpose of this paper is to study the long-term reliability of the Au stud bump treated by four different high temperature storage times (200°C for 0, 100, 200 and 300 h). Design/methodology/approach: The bonding strength and the fracture behavior are investigated by chip shear test. The experiment is further studied by microstructural characterization approaches such as scanning electron microscope, energy dispersive spectrometer and so on. Findings: It is recognized that there were mainly three typical fracture models during the chip shear test among all the Au stud bump samples treated by high temperature storage. For solder bump before aging, the fracture occurred at the interface between the Cu pad and the Au stud bump. As the aging time increased, the fracture mainly occurred inside the Au stud bump at 200°C for 100 and 200 h. When aging time increased to 300 h, it is found that the fracture transferred to the interface between the Au stud bump and the Al Pad. Originality/value: In addition, the bonding strength also changed with the high temperature storage time increasing. The bonding strength does not change linearly with the high temperature storage time increasing but decreases first and then increases. The investigation shows that the formation of the intermetallic compounds because of the reaction between the Au and Al atoms plays a key role on the bonding strength and fracture behavior variation. [ABSTRACT FROM AUTHOR]

The accumulation of alkali residue has led to significant contamination of soil, air, and water, posing a hazardous threat to the environment. To address this issue, a technology and method for producing alkali residue–based lightweight soil were proposed to facilitate the reuse of alkali residue, and the feasibility of this method was demonstrated. Compression tests, X-ray diffraction, X-ray fluorescence spectrometry, and scanning electron microscope (SEM) were conducted to investigate the strength characteristics and hardening mechanism of the material. The results indicate that the compressive strength of the alkali residue–based lightweight soil increases linearly with wet density, age, content of portland cement, and ground granulated blast slag. The optimal water–solid ratio was determined to be 0.6. Specimens with low and high strength exhibited plastic and brittle failures, respectively. The primary contributors to the material's compressive strength were identified as hydrated calcium silicate, ettringite, monosulfur calcium sulfoaluminate hydrate, hydrated calcium aluminate, and Friedel's salt. The 28-d compressive strength of the alkali residue–based lightweight soil, with a water–solid ratio of 0.6 and a wet density of 800.0 kg/m3 , was measured to be 1.17 MPa, meeting the requirements for most filling projects. [ABSTRACT FROM AUTHOR]

Potholes are one of the common diseases of asphalt pavements. Cold patching asphalt mixtures (CPAM) are a common material for pothole repair. Reclaimed asphalt pavement (RAP) is a high-potential sustainable material that is commonly used in pavement construction. The aim of this study is to address the balance between performance improvement and cost reduction in CPAM. To achieve this objective, the CPAM was prepared with four different contents of cutback and 100% RAP (RAP-CPAM) and its performances were evaluated by laboratory tests. First, Fourier transform infrared spectroscopy (FTIR) test and scanning electron microscope (SEM) technique were used to analyze the diffusion mechanism between the cutback and the artificial aged binder. Then, the rationality of the cutback content was preliminary estimated by the mixing test and the draindown test. Finally, the adhesion performance, cohesion performance, strength, and resistance to water damage of RAP-CPAM were characterized through laboratory tests. From the FTIR test, the carbonyl index of aged asphalt layer decreased compared to that of the artificial aged binder as the storage time increased. Simultaneously, SEM imaging of the artificial aged binder showed less fractured surfaces after storage. The results of FTIR and SEM tests indicate that the cutback and the artificial aged binder were diffused. It was found that 1.6% content of cutback was slightly lower for RAP-CPAM, and 2.8% was not excessive. Boiling test results show that RAP-CPAM had good adhesion performance. Rolling screen test, Marshall stability test, and immersion Marshall test results reveal that RAP-CPAM had good cohesion performance, strength, and resistance to water damage. Based on the performance evaluation, the optimal content of cutback in RAP-CPAM was determined as about 2.4%–2.8%. In conclusion, the cutback and the RAP binder were successfully diffused, thereby ensuring good performances of RAP-CPAM. [ABSTRACT FROM AUTHOR]

Nanofluids have demonstrated incredible potential for application in various industries such as coolants. Metal oxides are widely used as solid particles in formulations of nanofluids due to their advantages. Metal oxide-based nanoparticles (NPs), ZnO NPs were fabricated by the ultrasonically assisted co-precipitation method. The structure and morphology of the synthesized ZnO NPs were characterized using an array of analytical techniques including X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The XRD results showed that the purity of ZnO was obtained. The investigated nanofluids remained stable for a long time without substantial sedimentation. The present study deals with the corrosion assessment of St37 steel in nanofluids prepared with various concentrations of ZnO NPs. A scanning electron microscope coupled with energy-dispersive X-ray spectroscopy was used to determine the surface characteristics and elemental composition of low-carbon steel specimens both before and after corrosion tests. Notably, the nanofluid containing 0.05% by weight of ZnO nanoparticles demonstrated the highest corrosion prevention efficiency among the prepared nanofluids. Furthermore, impedance spectroscopy measurements revealed that the corrosion resistance increased by 72.9% for the nanofluid containing 0.05 wt% ZnO NPs compared to the base fluid. These findings highlight the potential of ZnO nanoparticles as an environmentally friendly anti-corrosion compound in cooling systems, effectively reducing corrosion degradation. [ABSTRACT FROM AUTHOR]