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Energy-dispersive x-ray spectroscopy and high-angle annular dark-field in a Cs-corrected scanning transmission electron microscope are employed to characterize the atomic-scale strain distribution in the active region of the InAs-based interband cascade laser. For the first time, energy-dispersive x-ray spectroscopy is utilized for the quantitative calculation of the zero-strain region, by which the geometric phase analysis of high-angle annular dark-field imaging has been carried out. The strain distribution of the active region with high accuracy has been obtained. The analysis of the out-of-plane strain shows that the active region in the InAs-based interband cascade laser is strain-compensated, while a certain degree of elemental intermixing still exists in the active region. This detailed strain distribution can provide valuable insights into the optimization of the growth conditions for the active region such as growth temperature, V/III flux ratio, and growth process to minimize the elemental intermixing and obtain a better performance interface while maintaining the strain-compensated state. [ABSTRACT FROM AUTHOR]

Packaging insulation materials with high thermal conductivity and excellent dielectric properties are favorable to meet the high demand and rapid development of third generation power semiconductors. In this study, we propose to improve the thermal conductivity of epoxy resin (EP) by incorporating a three-dimensional boron nitride thermally conductive network. Detailedly, polyurethane foam (PU) was used as a supporter, and boron nitride nanosheets (BNNSs) were loaded onto the PU supporter through chemical bonding (BNNS@PU). After immersing BNNS@PU into the EP resin, EP-based thermally conductive composites were prepared by vacuum-assisted impregnation. Fourier transform infrared spectrometer and scanning electron microscope were used to characterize the chemical bonding and morphological structure of BNNS@PU, respectively. The content of BNNS in BNNS@PU/EP composites was quantitatively analyzed by TGA. The results show that the thermal conductivity of the BNNS@PU/EP composites reaches 0.521 W/m K with an enhancement rate η of 30.89 at an ultra-low BNNS filler content (5.93 wt. %). Additionally, the BNNS@PU/EP composites have excellent dielectric properties with the frequency range from 101 to 106 Hz. This paper provides an interesting idea for developing high thermal conductivity insulating materials used for power semiconductor packaging. [ABSTRACT FROM AUTHOR]

Over the last two decades, Electron Energy Loss Spectroscopy (EELS) imaging with a scanning transmission electron microscope has emerged as a technique of choice for visualizing complex chemical, electronic, plasmonic, and phononic phenomena in complex materials and structures. The availability of the EELS data necessitates the development of methods to analyze multidimensional data sets with complex spatial and energy structures. Traditionally, the analysis of these data sets has been based on analysis of individual spectra, one at a time, whereas the spatial structure and correlations between individual spatial pixels containing the relevant information of the physics of underpinning processes have generally been ignored and analyzed only via the visualization as 2D maps. Here, we develop a machine learning-based approach and workflows for the analysis of spatial structures in 3D EELS data sets using a combination of dimensionality reduction and multichannel rotationally invariant variational autoencoders. This approach is illustrated for the analysis of both the plasmonic phenomena in a system of nanowires and in the core excitations in functional oxides using low loss and core-loss EELS, respectively. The code developed in this manuscript is open sourced and freely available and provided as a Jupyter notebook for the interested reader. [ABSTRACT FROM AUTHOR]

Low-energy ion beam irradiation, combined with the introduction of impurities, presents a promising approach for nanopatterning silicon (Si) surfaces. In this research, we investigate the surface evolution of Si (100) surfaces irradiated by 75 eV helium (He) plasma, in the presence of tantalum (Ta), traditionally regarded as an impurity incapable of initiating pattern formation, as evidenced in prior studies. The Ta impurities are pre-deposited onto the Si surfaces using the magnetron sputtering method, which offers a more controlled and quantifiable approach compared with the conventional co-deposition route. After irradiation at 800 K, dense cone arrays are produced on the Si surface. The growth of the cones is explored for fluence spanning (1–10) × 1025 m−2. The cross-sectional scanning electron microscope images indicate that the cone lengths and base width are well characterized by t1/2 dependence. The kinetics of the cone growth follow Fick's law, characterized by an effective diffusive mechanism with the coefficients of diffusion: D = 6.49 ± 0.83 × 10−16 m−2 s−1. Transmission electron microscope observations reveal that the cone has distinct inner and outer parts with different microstructures and a clear interface. The growth mechanism of these cones is elucidated as a composite process involving preferential sputtering, the destabilizing influence of He bubbles, and the migration of adatoms. [ABSTRACT FROM AUTHOR]

The scanning electron microscope (SEM) recordings of dynamic nano-electromechanical systems (NEMS) are difficult to analyze due to the noise caused by low frame rate, insufficient resolution, and blurriness induced by applied electric potentials. Here, we develop an image processing platform enhanced by the physics of the underlying system to track the motion of buckling NEMS structures in the presence of high noise levels. The algorithm is composed of an image filter, two data filters, and a nonlinear regression model, which utilizes the expected form of the physical solution. The method was applied to the recordings of a NEMS beam about 150 nm wide, undergoing intra- and inter-well post-buckling states with a transition rate of approximately 0.5 Hz. The algorithm can track the dynamical motion of the NEMS and capture the dependency of deflection amplitude on the compressive force on the beam. With the help of the proposed algorithm, the transition from inter-well to intra-well motion is clearly resolved for buckling NEMS imaged under SEM. [ABSTRACT FROM AUTHOR]

A non-destructive method for detecting sub-micrometer-sized micropipes on an entire wafer surface is investigated. Since it is difficult to detect sub-micrometer-sized micropipes due to their small core size, a non-destructively and accurately detecting method is required. To solve the issue, we focus on a characteristic depression generated around micropipes, namely, line-shaped depressions. In this paper, the location of line-shaped depressions is identified by using optical inspection, and the line-shaped depressions are distinguished whether micropipes exhibit line-shaped depression or not by using mirror electron microscope observation as high-resolution inspection. The accuracy of the distinction results is confirmed by scanning electron microscope observation, and electrical characteristics of the P–N diode are fabricated using the inspected wafer. Furthermore, the sub-micrometer-sized micropipes are observed at the sites of leakage current identified by emission microscopy. Additionally, device simulation of the blocking-voltage characteristics of P–N diodes suggests that the increase in leakage current depends on the electric field at the sub-micrometer-sized micropipes, regardless of their core size. [ABSTRACT FROM AUTHOR]

Gastropods forage with their radula, a thin chitinous membrane with embedded teeth, which scratch across the substrate to lose food particles. During this interaction, the risk of loosening particles is obvious without having a specialized mechanism holding them on the tooth surface. As mucus secretions are essential in molluscan life cycles and the locomotion and attachment gels are known to have an instant high adhesion, we have hypothesized that the saliva could support particle retention during feeding. As adhesion of snail saliva was not studied before, we present here an experimental setup to test its particle-binding capacity using a large land snail (Lissachatina fulica, Stylommatophora, Heterobranchia). This experiment was also applied to the gels produced by the snail foot for comparison and can be potentially applied to various fluids present at a small volume in the future. We found, that the saliva has high particle retention capacity that is comparable to the foot glue of the snail. To gain some insight into the properties of the saliva, we additionally studied it in the scanning electron microscope, estimated its viscosity in a de-wetting experiment, and investigated its elemental composition using energy dispersive X-ray spectroscopy reveling higher contents of Ca, Zn and other potential cross-linkers similar to those found in the glue. [ABSTRACT FROM AUTHOR]

Complex oxides La 0. 9 7 Ba 0. 0 3 MnO3, La 0. 7 3 Ba 0. 2 7 MnO3 and La 0. 5 Ba 0. 5 MnO3 were synthesized and their structural properties were studied. The structural investigation of the samples is done by incorporating X-ray diffraction (XRD) and scanning electron microscope (SEM) technique at room temperature. The Rietveld method was successfully used for the analysis of the obtained diffraction spectra. It was determined that these compounds have a perovskite structure. Partial substitutions La→Ba do not disturb the ideal perovskite structure and the cubic crystal structure with the space group Pm-3m is preserved. Crystallographic parameters, lattice parameters and interatomic distances were determined for each compound. As a result of SEM studies, it was determined that the size of crystallites in LaxBa 1 − x MnO3 solid solutions ranged from 2 to 10 μ m. [ABSTRACT FROM AUTHOR]

Compatible nanoparticle properties in photocatalytic applications are crucial. Within the scope of this investigation, we constructed a nanocomposite of ZnO and CuCo 2 O 4 (ZnO/CuCo 2 O 4) to boost the photocatalytic properties of ZnO by constructing ZnO/CuCo 2 O 4 nanocomposite using Artocarpus altili s leaves extracts (AALE). Essential secondary metabolites contribute to the origin of weak bases and capping agents to form the spherical shape of ZnO/CuCo 2 O 4. X-ray diffractometry (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy, ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), scanning electron microscope - energy dispersive X-ray spectroscopy (SEM-EDX) are some of the techniques that are utilized for the validation of nanocomposite properties, such as vibrational, crystallinity, band gap, morphology, particle size, and elemental composition. The formation of ZnO/CuCo 2 O 4 decreased the bandgap energy and enhanced the photocatalytic performance by 93.01 % under visible light irradiation for 2 h. ZnO/CuCo 2 O 4 followed pseudo-second-order kinetic in the photodegradation of malachite green (MG). It is noted that the increase in photocatalytic characteristics can be brought about by the narrower band gap of ZnO and increased kinetic rate toward dye degradation. Radical species analysis was of utmost importance in acknowledging that holes (h+) were the most crucial species that were indispensable to MG degradation. The photodegradation efficiency of the recycled catalyst only declines by approximately 12 % after five cycles of consumption. This study demonstrates a compelling method using plant extracts to prepare visible-light response ZnO-based nanocomposites for better photocatalytic activity and stability. [ABSTRACT FROM AUTHOR]

Orthorhombic stable phase of MoO 3 and Ni-doped MoO 3 with different weight percentages (2 %,5 % and 10 %) were successfully synthesized by following a surfactant free acid-assisted chemical co-precipitation method under optimized experimental conditions. Structural and compositional investigation using tools like X-ray diffraction and Raman spectroscopy verified the orthorhombic phase and structure quality of the prepared samples with findings from Raman consistent with those from XRD. The optical characteristics analysed using UV–Vis diffused reflectance spectroscopy and photoluminescence spectroscopy revealed that Ni2+ may act as a shallow acceptor at lower doping concentrations. It was observed that the structure and characteristics of MoO 3 dramatically altered as a function of Ni doping concentration, suggesting that Ni ions migrated from lattice substitution to grain boundaries. Images from field emission scanning electron microscope revealed the formation of layer-by-layer growth of micro-plate like morphology of the prepared samples with increasing agglomeration influenced by grain boundaries. EDAX spectrum confirmed the presence of Mo, O and Ni and their compositional proportion. Based on the properties analysed, the photocatalytic properties of the synthesized samples were analysed for degradation of Alizarin Red dye and kinetic studies were conducted. The optical characterization revealed defect induced emissions and the feasibility of MoO 3 acting as a photodetector was studied along with Ni-doping proving the versatility of material for multifunctional applications. [ABSTRACT FROM AUTHOR]

In this study, the porous graphite phase carbon nitride photocatalyst (P-g-C3N4) is prepared by the CaCO3 template method, and then P-g-C3N4/T-polyethylene terephthalate (T-PET) catalytic fibre is prepared by the padding method. P-g-C3N4 can provide more active sites than g-C3N4 as proved by the Brunauer–Emmett–Teller and the UV–Visible diffuse reflectance test. P-g-C3N4 powder catalyst successfully supports PET fibre as proved by scanning electron microscope, Fourier infrared spectroscopy and X-ray diffraction spectroscopy. The photocatalytic performance of P-g-C3N4/T-PET catalytic fibre is tested by constructing a single hexavalent chromium or hexavalent chromium/organic pollutant binary pollution system. The potential application value of P-g-C3N4/T-PET catalytic fibre is further explored by simulating the complex actual water environment. After five recycles, P-g-C3N4/T-PET catalytic fibre shows good catalytic performance. The mechanism of P-g-C3N4/PET photocatalytic degradation of organic pollutants is proposed through the capture agent experiment and electron paramagnetic resonance spectroscopy. Among them, •O2− is the most important active species of P-g-C3N4 catalytic fibre, which is used for the oxidation of organic pollutants. At the same time, photoelectrons generated by the catalytic fibre are used to reduce hexavalent chromium. The efficiency of P-g-C3N4 to remove pollutants is improved by using PET fibre as a carrier, which not only solves the problem of difficult recovery of powder catalysts but also provides more active sites. [ABSTRACT FROM AUTHOR]

Herein, the influence of P2O5 on the break temperature and phase composition of slag from the double slag converter steelmaking process is investigated comprehensively. The composition and micromorphology of crystallized phase are analyzed by X‐Ray diffractometer and scanning electron microscope equipped with energy dispersive spectrometer. The results reveal that the break temperature of slag increases owing to an increase of P2O5 content. When the P2O5 content is 2%, the break temperature is 1198 °C, and it increases to 1209 °C for the slag with 4% P2O5. With the increase of P2O5 content from 2% to 8%, the activation energy for viscous flow shows an upward trend. The crystallized phase at the same temperature with different P2O5 contents remains nearly unchanged, but the diffraction peak intensity is different. When the P2O5 content remains constant, a decrease in temperature results in significant changes in the micromorphology of crystallized phases. The present results improve the knowledge about the P‐rich slag, and are also significant in optimizing the double slag converter steelmaking process. [ABSTRACT FROM AUTHOR]

Mullite ceramic membrane is considered as microfiltration membrane suitable for oil-water (O/W) emulsion wastewater treatment. This study presented a facile sintering approach to prepare mullite ceramic membrane from coal fly ash. Various characterization techniques, such as X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), shrinkage and apparent porosity, bending strength etc. were used to reveal the effect of MoO 3 addition and sintering temperature on ceramic membrane. At sintering temperature 1300 °C, adding 5 wt% MoO 3 , the apparent porosity of membrane is 46.04%, the bending strength is 32.11 MPa, and the average pore size is 0.190 μm. Finally, whisker mullite ceramic membranes were applied for deep treatment of oily wastewater. As-synthesized ceramic membrane exhibits excellent permeate flux (391.10 L·m−2·h−1) and oil rejection (97%) for separation of O/W emulsion. The membrane fouling is mainly controlled by cake filtration mechanism. Meanwhile, the ceramic membranes show good regeneration performance and acid and alkali resistance. This study provides theoretical and technical support for preparation of whisker mullite ceramic membranes from fly ash and deep treatment of oily wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

The studies presented in this paper constitute the first scientific attempt to interpret the manner whereby notched implements made of scapulae were made and used. These implements have been found at numerous European and non-European sites, usually dated to the Neolithic–Early Iron Age (predominantly the Early Bronze Age). Research has examined these products since the beginning of the 20th century, resulting in the development of several hypotheses regarding their functions. This paper presents the analysis results of 41 such artefacts from the early Bronze Age defensive settlement in Bruszczewo (central Poland). This is the largest collection of these products from a single site worldwide. The artefacts were subjected to multi-aspect traceological tests (both technological and functional) using optical, metallographic, and scanning electron microscopes. The residues identified on their surfaces were analysed using optical microscopy and scanning electron microscopy and energy dispersive X-rays spectroscopy. Moreover, the studies reported herein involved extensive experimental research. Consequently, the chain of operations followed in producing these tools was reconstructed and the use-wear traces present on their surfaces were classified; it was determined that these tools were most likely used for threshing cereals but might also have been used for threshing legumes. This is the first proof of threshing in central Europe in the Early Bronze Age and the first scientifically substantiated hypothesis regarding the function of these important artefacts. [ABSTRACT FROM AUTHOR]

Highlights The utilization of continuous fiber‐reinforced thermoplastic composites (CFRTP) in additive manufacturing technology (AM) is envisioned to enable the production of high‐performance parts with enhanced mechanical properties. In the production of CFRTP filaments, ensuring proper impregnation plays a crucial role in improving the characteristics of the produced filament. Carbon fiber (CF) reinforced polyphenylene sulfide (PPS) composites find applications in secondary aerospace parts, automotive structural parts, and chemical process applications. Continuous CF‐reinforced PPS filaments enable the production of lightweight, high‐performance parts with mechanical strength, heat, and chemical resistance in AM. In the present study, continuous CF‐reinforced PPS filaments were produced using the melt impregnation method for use in fused deposition modeling technology. Filament diameter, geometrical evenness, and effective fiber impregnation are important criteria in filament production. An impregnation mold was designed and manufactured to provide impregnation. The influence of three different pin angles (56°, 70°, and 82°) on impregnation and mechanical properties has been investigated by developing an impregnation die for CFRTP filament production. Tensile testing, fiber content analysis, optical microscopy, and scanning electron microscope analysis were performed on the produced filaments. Furthermore, increasing the pin angle leads to an increase in both the spreading and impregnation of fibers. Impregnation die for effective wetting of fibers with polymer. Significance of pin angle in fiber spreading and wetting with polymer. Application of test standards for fiber content. [ABSTRACT FROM AUTHOR]

Highlights Processing parameters during the laser‐radiated in‐situ manufacturing process change the thermal history of the thermoplastic composite, which affects porosity and fiber‐resin interfacial bonding quality, and hence the wedge peel strength of the laminate. The effect of different laser powers and consolidation forces on the wedge peel strength of the specimens was investigated. Due to the fiber‐rich area on the tape surface during the laser heating phase as well as the insufficient consolidation force and consolidation length during the consolidation phase, the wedge peel strength decreased due to increased porosity and weak fiber‐resin bonding at the interlayer bonding interface. A conformable consolidation roller of lower hardness was used to improve the wedge peel strength of the laminates, which reduced the initial temperature of the cooling phase, thus inhibiting the void rebound and increasing the bonding strength at the fiber‐resin interface. The cross‐section and peeling surface were characterized by optical microscope and scanning electron microscope. The wedge peel strength of the laminates, with reduced voids and increased interfacial bonding strength between the fibers and the resin, is improved. Mechanism of void formation and evolution in different phases of laser‐radiated in‐situ consolidated laminate. Effect of consolidation roller hardness and deformation on wedge peel strength. [ABSTRACT FROM AUTHOR]

Transparent conductive oxide (TCO) thin films are highly sought-after for their unique characteristics of conducting electricity and transmitting visible light, making them ideal conductive coating materials for electronic devices. We carried out a comprehensive analysis of the deposition, optical, electrical, and structural properties of ITO and Ag/ITO thin films on glass substrates in this study. The weight ratio of the deposited metals was 1:10, 2:10, and 4:10 wt.% (Sn:In) for ITO films and 1:1:10 wt.% (Ag:Sn:In) for Ag–ITO film. The films were annealed at 300°C using a program controller furnace. We employed infrared cameras to analyze the surface temperature profiles of these thin films under external voltage supply. We also investigated the resistivity behavior of both ITO and Ag–ITO films, analyzing them with regard to Mott's variable range hopping (VRH) model and the fluctuation-induced tunneling model. Scanning electron microscope images revealed that adding Ag increased the grain size of ITO thin films. The average grain size for ITO thin film was determined as 186 nm, while it was found to be 270 nm for Ag–ITO thin film. Furthermore, incorporating Ag into the ITO thin film resulted in a reduction of 21.5% in transmittance over the complete visible range of the electromagnetic spectrum when compared to the ITO thin film without Ag as measured by ultra-visible spectrophotometer. The figure of merit was obtained as 0. 3 4 4 × 1 0 − 3 Ω − 1 for ITO and 0. 0 5 2 4 × 1 0 − 3 Ω − 1 for Ag–ITO thin films. However, the resistance of the ITO thin film was calculated to be 9.58 k Ω , while that of the Ag–ITO film was found to be 6.99 k Ω. The ITO thin film that included Ag exhibited a lower electrical resistivity due to the larger grain size caused by doped Ag atoms in the structure, leading to less electron scattering at the grain boundaries and a resulting decrease in resistivity as determined by four-point probe system. Thermal imaging camera measurements revealed that the surface temperature of the ITO thin film decreased with the addition of Ag under high voltage application, but not under low voltage. When a voltage of 350 V and 250 V was applied to the thin films, the ITO film exhibited a surface temperature of 73.9°C and 50.4°C, whereas under identical conditions, the Ag–ITO film showed a surface temperature of 62°C and 44.1°C, respectively. Furthermore, both films exhibited exponentially increasing surface temperature behavior under a certain voltage, suggesting that they have potential for transparent heaters and high-voltage/low-current applications. [ABSTRACT FROM AUTHOR]

Introduction: Internal erosion triggered by water pipeline leaks seriously threatens the stability of the urban ground. Hangzhou, a city in Zhejiang Province, China, is facing critical challenges due to urban ground collapse (UGC) caused by internal erosion. However, there is a lack of research on the prevention of UGC by improving the internal erodibility of underground soil. Addressing this issue is of utmost importance to ensure the city's stability and safety. This paper proposes to improve the internal erodibility of typical sandy silt soils with chemical stabilisers. Methods: The effects of three chemical stabilisers, lignosulphonate (LS), lime (LI), and lignin fibre (LF), on the critical shear stress (rc) and erosion coefficient (kd) of sandy silt soils were investigated, which from Hangzhou, Zhejiang, China, by the hole erosion test (HET) at different mixing amounts and at different conservation times. Results: The findings indicate that LF mainly improves the erosion resistance of sandy silt by increasing rc, and the maximum increase is 2.38 times; LI mainly improves the erosion resistance by decreasing kd, and the maximum decrease is 2.18 times. After adding LS, rc and kd did not change significantly. The scanning electron microscope (SEM) test revealed that the inclusion of LF led to the formation of larger agglomerates in the sandy silt soil. The microstructure of sandy silt soil remained dispersed even after adding LS. Various chemical stabilisers used to improve sandy silt soils exhibited distinct erosion mechanisms. Sandy silt soils improved with LF exfoliated into agglomerates, displaying high resistance to erosion. On the other hand, the sandy silt treated with LF still lacks a protective layer and shows minimal improvements in its ability to withstand erosion. In contrast, the LS-amended sandy silt remains stripped with individual soil particles with insignificant changes in erosion resistance. Discussion: This study can provide a conceptual framework for choosing foundation treatment techniques in future urban development projects. [ABSTRACT FROM AUTHOR]

In the current study, the effect of ozone gas on the mortality of Acanthoscelides obtectus adults on stored common bean seeds was assessed. Ozone was evaluated at concentrations of 500, 1000 and 1500 ppmv and three exposure times. Changes in the cuticle of adults were examined under scanning electron microscope, and the chemical composition of common bean seeds treated with ozone was determined. Mortality of A. obtectus adults was improved with increase of ozone concentration and exposure time. A full mortality of A. obtectus adults was achieved 4 days post treatment by all tested concentrations at exposure time 3 h. Examination with scanning electron microscope of A. obtectus adults showed scratches of the elytra surface in different areas of the body cuticle. Moreover, sensilla were absent in some points leaving spaces between parts on the dorsal surface. Furthermore, the chemical composition analysis of treated seeds showed a slight decrease in protein, fat and carbohydrate, moisture, and a slight increase in fat, fiber and ash contents compared with untreated seeds. Our findings suggest ozone can effectively protect common bean seeds against A. obtectus beetle. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have excellent flexibility, unique optical transmittance and high conductivity. The polyol process is appropriate for preparing AgNWs due to its simplicity, effectiveness, low cost, and high yield. This work aims to investigate the effect of preparation parameters of the polyol process on the silver nanowires properties. The parameters include the controlling agent, molecular weight of the polyvinylpyrrolidone (PVP), the temperature, and the reducing agent. The amount of silver nanoparticles formed during preparation was used to determine the optimum preparation conditions. The transmission electron microscope (TEM) images showed minimal amount of Ag nanoparticles when using mixed molecular weight of PVP-40K, and PVP-1.3M at 150 °C with the assistance of copper chloride as a controlling agent. The prepared AgNWs had an average length of 3.7 µm and aspect ratio of 15.3. The fabricated electrodes were characterized using a scanning electron microscope (SEM) and four probe resistivity measurements. The electrical measurement of the AgNWs electrodes indicated that the surfactant thickness is a critical parameter in having low sheet resistance electrodes. Also, the optical transmission was affected by the amount of nanoparticles. The prepared electrode with high concentration of AgNWs and a minimal amount of nanoparticles exhibited 80% optical transmission. [ABSTRACT FROM AUTHOR]

Single-layer isophorone diisocyanate (IPDI) are one of the most popular self-healing microcapsules but suffers from low shell strength, poor heat resistance, stability and aging properties. In this paper, IPDI microcapsules were encapsulated into double-layer phenolic (PF)/polyurethane (PU) by a two-step process involving interfacial polymerization and in-situ polymerization. The prepared microcapsule composites were comprehensively characterized for their physical and chemical properties using optical microanalysis, scanning electron microscope, Fourier transform infrared spectroscopy, thermal gravimetric analysis and depth-sensing indentation analysis. Compared with the single-layer PU-IPDI microcapsule counterpart, the mechanical performance, thermal resistance, aging property and environmental stability of double-layer PF/PU-IPDI microcapsules were significantly improved. The epoxy coating was enhanced with the incorporation of 10 wt.% PF/PU-IPDI microcapsules, whose self-healing performance was evaluated by scratch corrosion test. The results demonstrated successful repair of coating scratches, along with the absence of corrosion on the coated steel substrate soaked in a 10 wt.% NaCl solution for 7 days. By comparing the tensile strength of epoxy coating before and after crack formation, it could be found that the self-healing efficiency was 57.9% when loaded with 10 wt.% of PF/PU-IPDI microcapsules in coating. This study highlights that the rational design of double-layer microcapsules integrated into the epoxy coating matrix could provide excellent anti-corrosion and self-healing properties. [ABSTRACT FROM AUTHOR]

Background: The integration of stem cells, signaling molecules, and biomaterial scaffolds is fundamental for the successful engineering of functional bone tissue. Currently, the development of composite scaffolds has emerged as an attractive approach to meet the criteria of ideal scaffolds utilized in bone tissue engineering (BTE) for facilitating bone regeneration in bone defects. Recently, the incorporation of polycaprolactone (PCL) with hydroxyapatite (HA) has been developed as one of the suitable substitutes for BTE applications owing to their promising osteogenic properties. In this study, a three-dimensional (3D) scaffold composed of PCL integrated with HA (PCL/HA) was prepared and assessed for its ability to support osteogenesis in vitro. Furthermore, this scaffold was evaluated explicitly for its efficacy in promoting the proliferation and osteogenic differentiation of canine bone marrow-derived mesenchymal stem cells (cBM-MSCs) to fill the knowledge gap regarding the use of composite scaffolds for BTE in the veterinary orthopedics field. Results: Our findings indicate that the PCL/HA scaffolds substantially supported the proliferation of cBM-MSCs. Notably, the group subjected to osteogenic induction exhibited a markedly upregulated expression of the osteogenic gene osterix (OSX) compared to the control group. Additionally, the construction of 3D scaffold constructs with differentiated cells and an extracellular matrix (ECM) was successfully imaged using scanning electron microscopy. Elemental analysis using a scanning electron microscope coupled with energy-dispersive X-ray spectroscopy confirmed that these constructs possessed the mineral content of bone-like compositions, particularly the presence of calcium and phosphorus. Conclusions: This research highlights the synergistic potential of PCL/HA scaffolds in concert with cBM-MSCs, presenting a multidisciplinary approach to scaffold fabrication that effectively regulates cell proliferation and osteogenic differentiation. Future in vivo studies focusing on the repair and regeneration of bone defects are warranted to further explore the regenerative capacity of these constructs, with the ultimate goal of assessing their potential in veterinary clinical applications. [ABSTRACT FROM AUTHOR]

Vector-borne diseases resulted into several cases of human morbidity and mortality over the years and among them is filariasis, caused by the mosquito Culex quinquefasciatus. Developing novel strategies for mosquito control without jeopardizing the environmental conditions has always been a topic of discussion and research. Integrated Vector Management (IVM) emphasizes a comprehensive approach and use of a range of strategies for vector control. Recent research evaluated the use of two entomopathogenic fungi; Beauveria bassiana and Lecanicillium lecanii in IVM, which can serve as potential organic insecticide for mosquito population control. However, their combined efficacy has not yet been evaluated against mosquito control in prior research and a gap of knowledge is still existing. So, this research was an attempt to bridge up the knowledge gap by (1) Assessing the combined efficacy of Beauveria bassiana and Lecanicillium lecanii on Culex quinquefasciatus (2) To investigate the sub-lethal concentration (LC50) of the combined fungal concentration and (3) To examine the post-mortem effects caused by the combined fungal concentration under Scanning Electron Microscope (SEM). The larval pathogenicity assay was performed on 4th instar C. quinquefasciatus larvae. Individual processed fungal solution of B. bassiana and L. lecanii were procured and to test the combined efficacy, the two solutions were mixed in equal proportions. To evaluate the sub-lethal concentration (LC50), different concentrations of the combined fungal solution were prepared by serial dilations. The mortality was recorded after 24 hours for each concentration. Upon treatment and evaluation, The LC50 values of B. bassiana and L. lecanii were 0.25 x 104 spores/ml and 0.12 x 104 spores/ml respectively and the combined fungal concentration was 0.06 x 103 spores/ml. This clearly indicated that the combined efficacy of the fungi is more significant. Further, SEM analysis revealed morphological deformities and extensive body perforations upon combined fungal treatment. These findings suggested that combining the two fungi can be a more effective way in controlling the population of Culex quinquefasciatus. [ABSTRACT FROM AUTHOR]

Thorium biosorption by a green microalga, Chlorella Vulgaris, was studied in a stirred batch reactor to investigate the effect of initial solution pH, metal ion concentration, biomass dosage, contact time, kinetics, equilibrium and thermodynamics of uptake. The green microalgae showed the highest Th adsorption capacity at 45 °C for the solution with a thorium concentration of 350 mg L−1 and initial pH of 4. The amount of uptake raised from 84 to 104 mg g−1 as the temperature increased from 15 to 45 °C for an initial metal concentration of 75 mg L−1 at pH 4. Transformation Infrared Spectroscopy (FTIR) was employed to characterize the vibrational frequency changes for peaks related to surface functional groups. Also, the scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to determine the morphological changes and elemental analysis of the biosorbent before and after the sorption process. The Langmuir isotherm was in perfect agreement with the equilibrium empirical data of thorium biosorption and the highest sorption capacity of the Chlorella Vulgaris microalgae was determined as 185.19 mg g−1. Also, the results of kinetic studies show that the thorium biosorption process follows a pseudo-second-order kinetic model. The negative value of ΔG0 indicates spontaneity and the positive values of ΔH0 indicate the endothermic nature of the adsorption process. [ABSTRACT FROM AUTHOR]

Reactor pressure vessel (RPV) studs are key components of nuclear reactors, and their connection with flange ensures the sealing of the RPV under high-pressure and high-temperature conditions. In the present work, the external threads of the RPV stud were prepared by triaxial rolling, and the texture evolution of the external thread root material of an RPV stud was predicted by finite element analysis coupled with viscoplastic self-consistent simulations. The microstructure of the external thread root material of RPV stud was characterized by scanning electron microscope and electron back-scattered diffraction. The installation characteristics of the turned and rolled parts of the RPV stud were tested by installation and pretightening tests. It was found that the dynamic recrystallization at the external thread root formed ultrafine tempered sorbite grains, high-angle grain boundaries (47%), and strong {111} <110> and {111} <112> textures. In the installation and pretightening test, the residual elongation of rolled parts was reduced by 6% under the same loading pressure. The triaxial rolling process distributed the microstructure of the external thread root of the RPV stud in a gradient manner, resulting in improved stud installation characteristics. [ABSTRACT FROM AUTHOR]

Parasites pose significant challenges to aquaculture and fisheries industries. Our study focuses on the Polyonchobothrium magnum and African catfish to address a potential health issue in aquaculture, explore host–parasite interactions that can help develop effective management practices to ensure fish health and industry sustainability. P. magnum was isolated from the stomach of African catfish (Clarias gariepinus) as the primary site of infection, with a prevalence of 10%. Most affected fish were heavily infected (8 out of 10). Infection was confirmed by sequencing the PCR‐targeted region of the nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) gene, along with light and scanning electron microscopes. The parasite had an elongated scolex with deep bothria, a prominent apical disc wider than the scolex itself, and a four‐lobed appearance. The scolex contained a central rostellum divided into two semicircles, bearing 26–30 hooks, with an average of 28. The apical disc had large hooks arranged in four quadrants, with 6–8 hooks each, averaging 7 per quadrant. No neck was observed. Phylogenetic analysis of our sequence showed a 100% match with isolates from Guangzhou, China. In infected fish, the anterior kidney showed increased expression levels of nuclear factor kappa B and lysozyme, but decreased levels of in major histocompatibility complex antigen II. Plasma analysis revealed a significant drop in superoxide dismutase, a rise in interleukin‐1 beta, and lower IgM levels compared to non‐infected controls. Non‐infected fish displayed greater gut microbiota diversity, with dominant families including Moraxellaceae, Enterobacteriaceae, Fusobacteriaceae, and Caulobacteraceae, and prevalent genera such as Acinetobacter, Cetobacterium, and Brevundimonas. In contrast, infected fish exhibited very low diversity, with significantly higher proportions of Enterobacteriaceae (45.99%) and Aeromonadaceae (41.79%) compared to non‐infected fish, which had 13.76% and 3.64% respectively. Cetobacterium somerae was prevalent in non‐infected fish, while infected fish harboured Aeromonas fluvialis, Plesiomonas shigelloides, and Gallaecimonas xiamenensis. Overall, P. magnum disrupted the immune status and gut microbiota of the host, thereby impacting its health. [ABSTRACT FROM AUTHOR]

Counting growth layers in dentine and/or secondary cementum is widely used for age determination in wild mammals but the underlying seasonal changes in the structure and degree of mineralisation of dental tissue have not been well characterised. We embedded first (m1) and second (m2) mandibular permanent molar teeth from a 12‐year‐old female Svalbard reindeer (Rangifer tarandus platyrhynchus) in PolyMethylMethAcrylate (PMMA), prepared cut and polished surfaces coated with evaporated carbon and used 20 kV back‐scattered electron imaging in a scanning electron microscope (BSE‐SEM) to study aspects of dental tissue structure which depend on the degree of mineralisation at the micron and sub‐micron scale. BSE‐SEM revealed differences between the mineral content of growth layers (annulations) in the secondary cementum and the primary and secondary dentine, the latter, incidentally, still forming at death in m1. Wide bands of less well mineralised tissue formed in the cementum during active appositional phases. Thin, denser bands formed by maturation‐mineralisation of existing tissue when growth slowed in winter. This maturation mimics the processes seen in lamellar bone and articular cartilage. Counter to previous suggestions, there was evidence of substantial resorption and repair of the secondary cementum and of formation of dentine throughout life. Secondary dentine is layered by mineral content like cementum. In the crown, this was mainly tubular dentine with well‐marked interglobular dentine layers. In the lower pulp chamber and root, it was largely without tubules. Substantial non‐mineralised spaces found at the cement‐dentine junction in the root apical regions in m2 represent inclusions of the Hertwig's Epithelial Root Sheath (HERS) or the Epithelial Rests of Malassez (ERM) between the two tissues, a phenomenon which has previously only been identified in Muridae. The anatomical changes which result in the formation of the incremental lines (annulations) in dental tissues of reindeer, identified here for the first time at the micrometre level, are likely to be common across most if not all long‐lived species of mammals living in seasonal environments. [ABSTRACT FROM AUTHOR]

In this study, we present the fabrication of large single-domain ternary (Sm,Eu,Gd)Ba 2 Cu 3 O 7-y bulk superconductor with enhanced superconducting properties using various REBa 2 Cu 3 O y (RE-123) as a liquid source via the top-seeded infiltration growth process (TSIG) in air. We employed a 1:1 ratio of REBa 2 Cu 3 O y (RE = Sm, Gd, Y and Er) and Ba 3 Cu 5 O 8 as a liquid source for fabrication. Impressively, all the obtained bulk samples exhibited a superconducting transition temperature T (c, onset) above 94 K. However, the bulk sample fabricated using Y-123 + Ba 3 Cu 5 O 8 as a liquid source demonstrated a T (c, onset) of 94.53 K, with a 40.14 % improvement in transition width (Δ T c) and at 77 K the bulk recorded a self-field critical current density (J c) value of 44.73 kA/cm2 & 10.62 kA/cm2 at 1T resulting in a remarkable 93.08 % improvement in self-field J c compared to the bulk sample fabricated using Er-123 + Ba 3 Cu 5 O 8. Microstructural analysis using a scanning electron microscope revealed a significant reduction in the mean size of secondary (211) phase particles, a significant reduction of 38.41 % is observed for the Y-123 + Ba 3 Cu 5 O 8 employed sample. [ABSTRACT FROM AUTHOR]

The solubility/degradability of bioactive glasses play crucial role in bone tissue engineering applications owing to the release of ions from their structure, which exert therapeutic effects on tissues. The present study evaluates the findings of a detailed investigation on the main features and solubility behaviors of newly formulated Nb incorporated glasses (Nb-BGs). New glass formulation in SiO 2 –CaO–Na 2 O–P 2 O 5 –CaF 2 –SrO–xNb 2 O 5 (x: 0.0, 0.5, 1.0, and 1.5 mol. %) system was successfully synthesized by melt-quenching technique. Glass composition was verified with Energy Dispersive X-ray Fluorescence spectrometer analysis and its amorphous nature, functional groups of the matrix and morphological features were identified via X-Ray diffraction analyses, Fourier Transform Infrared Spectroscopy and Scanning Electron Microscope analysis, respectively. Network connectivity (NC) of the Nb-BGs was assessed with respect to the role of Nb 2 O 5 in the glass matrix as network former, modifier, or both. In order to evaluate the in vitro solubility of Nb-BGs, released concentrations of particular ions from the glass compositions were determined at certain time points and comprehensively discussed with several mathematical models such as zero-order, first-order, second-order, Higuchi, and Korsmeyer-Peppas for the first time. Results showed that the incorporation of Nb 2 O 5 (up to 1.5 mol. %) increased the density, oxygen density as well as NC values of newly formulated glasses. Si, Na and Ca ions which play a main role in well-defined Hench's mechanism followed mostly second-order release kinetics for all glasses in the mathematical models studied. When the Nb content increase (to 1.5 mol. %) in glass composition, the release mechanism of Si ion according to Korsmeyer-Peppas model shifts from the diffusion mechanism to an erosion-dominant release mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

The crystal structure of La 0.7 Sr 0.3 Mn 1−x Al x O 3 (LSMAO) with x = 0,0.025,0.05,0.075 and 0.10 ceramics prepared by the Sol-gel method were investigated by employing the XRD technique. The XRD patterns analysis by employing the Rietveld analysis confirms the nonexistence of secondary crystal phase/s and, materials are crystallized to the R-3c(167) space group. The microstructural properties were studied using scanning electron microscope (SEM) and transmission electron microscope (TEM). The dielectric property, AC conductivity, complex impedance spectroscopy and complex electrical modulus have been studied over a wide range of frequencies (103 Hz–107 Hz) at different temperatures from 313K to 393K. The Non-Debye type relaxation process has been observed in synthesized samples confirmed from the Nyquist plot. The Cole-Cole plots were employed to estimate the individual grain and grain boundary contributions. The Maxwell-Wagner (MW) polarization model provides an explanation for the greater values of dielectric constant at the lower frequencies. The present study explores the technological usefulness of LSMAO. [ABSTRACT FROM AUTHOR]

Background: Brinzolamide (BRI) suspensions are used for the treatment of glaucoma; however, sufficient drug delivery to the target tissue after eye drop administration is hampered by poor solubility. To address this issue, we focused on nanocrystal technology, which is expected to improve the bioavailability of poor-solubility drugs, and investigated the effect of BRI nanocrystal formulations on corneal permeability and intraocular pressure (IOP)-reducing effect. Methods: BRI nanocrystal formulations were prepared by the wet-milling method with beads and additives. The particle size was measured by NANOSIGHT LM10, and the morphology was determined using a scanning probe microscope (SPM-9700) and a scanning electron microscope (SEM). Corneal permeability was evaluated in vitro using a Franz diffusion cell with rat corneas and in vivo using rabbits, and the IOP-reducing effect was investigated using a rabbit hypertensive model. Results: The particle size range for prepared BRI nanocrystal formulation was from 50 to 300 nm and the mean particle size was 135 ± 4 nm. The morphology was crystalline, and the nanoparticles were uniformly dispersed. In the corneal permeability study, BRI nanocrystallization exhibited higher corneal permeability than non-milled formulations. This result may be attributed to the increased solubility of BRI by nanocrystallization and the induction of energy-dependent endocytosis by the attachment of BRI nanoparticles to the cell membrane. Furthermore, the addition of tyloxapol to BRI nanocrystal formulation further improved the intraocular penetration of BRI and showed a stronger IOP-reducing effect than the commercial product. Conclusions: The combination of BRI nanocrystallization and tyloxapol is expected to be highly effective in glaucoma treatment and a useful tool for new ophthalmic drug delivery. [ABSTRACT FROM AUTHOR]

Two types of cells targeting Peptides, TAMS-1 (CSPGAKVRCY {Lys (Biotin)}) and MDSC-peptide (Biotin {PEG4}-MEWSLEKGYTIK), were synthesized for targeting CD206 M2 macrophage and myeloid-derived suppressor cells (MDSC), respectively. Each peptide was coaxially electro sprayed where PCL (Polycaprolactone) is the core, and the peptide is the sheath to create a PCL nanoparticle with peptides. Electro spraying parameters included applying a voltage of 44 kV, humidity between 35–44%, tip to collector distance at 160 mm, core flow rate of 0.5 ml/hr, and a sheath flow rate of 0.7 ml/hr. UV–VIS (Ultraviolet–Visible) spectrometry, SEM (Scanning Electron Microscopy) imaging, and in vivo biodistribution techniques were used to study the morphology and performance of the PCL-peptide nanoparticles. Peak absorbance values for PCL were found at around 275 nm. Peptides absorbance value was observed between 230 and 250 nm. Scanning Electron Microscope image shows nanoparticles as small as 100 nm and agglomerates as large as 1 µm. In-vivo biodistribution of PCL and CD206 M2 macrophage targeting peptide (TAMS-1) nanoparticles after intravenous injection in the tumor mice model showed uptake to the tumors. On the other hand, MDSC peptide did not show any uptake to the site of tumors. Most activity is shown in the intestine indicating excretion of the agents through the hepato-biliary system. [ABSTRACT FROM AUTHOR]

Eight kinds of patterned discharges are obtained by changing the discharge parameters in a dielectric barrier discharge with modulated gas gaps, which are applicable to materials patterned treatment. A square superlattice pattern consisting of two dot sublattices and one ring sublattice is studied and used to treat a PI film. The formation mechanism is studied by intensified charge coupled device. The spatial distribution of the plasma parameters is measured using optical emission spectra. The gas temperatures as well as the electron densities of the three sublattices are significantly different from each other. The physical and chemical properties of the treated film are measured using a surface profiler, x-ray photoelectron spectroscopy, and scanning electron microscope. The transmissivity, wettability, and etching depth of the treated PI film demonstrate square superlattice pattern distribution, which verifies the predictions based on plasma parameter measurements. The dielectric barrier discharge device reported here is also applicable to materials' patterned growth. [ABSTRACT FROM AUTHOR]

Nanoscale subsurface characterization technologies based on the scanning electron microscope platform offer incomparable advantages of nondestructiveness and penetration depths up to the micrometer scale. However, the electron beam can serve not just as a mechanical/electrical excitation source but also as an excellent nanoscale thermal excitation source, which can facilitate the development of nanoscale subsurface imaging methods based on the Seebeck effect in semiconducting materials. In this work, a subsurface nondestructive imaging technology, scanning thermoelectric capacitance microscopy (STeCM), was developed based on the interaction between a non-steady-state electron beam and semiconducting materials, exploiting the Seebeck effect. In STeCM, a square wave-modulated hot electron beam with huge kinetic energy excites a "thermal wave" in the subsurface local region of the semiconducting sample. The heated local region, acting as a thermoelectric capacitor, undergoes cyclic charging and discharging, leading to the generation of periodic current due to non-equilibrium carrier migration. The second-order harmonic component of this current is demodulated to visualize embedded local thermal/thermoelectric inhomogeneities. Amazingly, for STeCM sample, only a smooth or polished surface is required, eliminating the need for any microfabrication, which will effectively decrease the configuration difficulty in the experiment. STeCM offers an alternative subsurface nondestructive imaging technology for more efficient, simple, and robust characterization. [ABSTRACT FROM AUTHOR]

Organic dyestuff are mostly toxic compounds that pose serious dangers to the environment. Adsorption using low-cost adsorbents is the most favorable method for its economic aspects. Recently, geopolymers have been introduced as an effective adsorbent for dyes and heavy metals. In this investigation, the synthesis of geopolymers from fired brick waste (Homra) was studied with full characterization using X-ray Diffraction, Fourier Transform Infrared Spectroscopy, Brunauer–Emmett–Teller, Energy dispersive X-ray, Scanning electron microscope tests and Transmission electron microscopy. The synthesized nano-Homra geopolymer (NHGP) was then subjected to the removal of one of the most used basic dyes, Methylene Blue (MB). Adsorption optimization was applied using Response surface methodology to study dye adsorption by the synthesized nano-geopolymer. The independent variables studied were: temperature, contact time, and concentration of dye in the elimination process, which were varied in the range of (25–60 ℃), (10–180 min), and (20–300 mg/L) respectively. The results obtained from ANOVA indicated that the maximum removal efficiency of 95% and adsorption capacity of 80.65 mg/g at a temperature of 59 ℃, contact time of 163 min, and an initial concentration of 254 mg/L. The results showed that the data obtained from the adsorption of MB onto NHGP was compatible with the Pseudo second order (R2 = 0.9838) and Langmuir isotherm model (R2 = 0.9882). [ABSTRACT FROM AUTHOR]

Fucosterols have been widely studied for their antioxidant, anticancer, and anti-inflammatory properties. However, they have not yet been studied in the field of dentistry. This study aimed to determine whether pretreatment of dentin with fucosterol before resin restoration enhances bond stability in resin-dentin hybrid layers. After applying 0.1, 0.5, and 1.0 wt% fucosterol to demineralized dentin, microtensile bond strength (MTBS) and nanoleakage tests were performed before and after collagenase aging, and the surface was observed using scanning electron microscope (SEM). The fucosterol-treated group showed better bond strength and less nanoleakage both before and after collagenase aging, and the corresponding structures were confirmed using SEM. MMP zymography confirmed that the activity of MMPs was relatively low along the concentration gradient of fucosterol, and the FTIR analysis confirmed the production of collagen crosslinks. In addition, fucosterol exhibits cytotoxicity against Streptococcus mutans, the main cause of dental decay. The results of this study suggest that fucosterol pretreatment improves bond strength and reduces nanoleakage at the resin-dentin interface, possibly through a mechanism involving collagen cross-link formation via the inhibition of endogenous and exogenous MMP activity. This study demonstrates the potential of fucosterol as an MMP inhibitor in dentin, which contributes to long-term resin-dentin bond stability and can be used as a restorative material. [ABSTRACT FROM AUTHOR]

Background: Toxoplasmosis, caused by Toxoplasma gondii , poses serious health issues for humans and animals. Individuals with impaired immune systems are more susceptible to severe toxoplasmosis. Pregnant women infected by T. gondii can face the possibility of birth defects and miscarriages. While pyrimethamine and sulfadiazine are commonly used drugs in clinical practice, concerns over their side effects and resistance are on the rise. A spider peptide XYP1 isolated from Lycosa coelestis had potent anti-T. gondii effects, but it had a high synthesis cost and strong cytotoxicity. Methods: This study intended to modify XYP1 for producing derived peptides via amino acid truncation and substitution. The anti-T. gondii effect was evaluated by trypan blue staining assay and killing experiment of RH strain tachyzoites. The CCK8 and hemolysis assays were used to compare their safeties. The morphological changes of T. gondii were observed by scanning electron microscope and transmission electron microscope. In addition, the mechanism of XYP1 against T. gondii through RNA-sequencing was further explored. Results: In vivo and in vitro experiments revealed that XYP1-18 and XYP1-18-1 had excellent anti-T. gondii activity with lower cytotoxicity and hemolysis activity than XYP1. XYP1, XYP1-18, and XYP1-18-1 were able to disrupt the surface membrane integrity of T. gondii tachyzoites, forming pores and causing the disruption of organelles. Furthermore, RNA-sequencing analysis indicated that XYP1 could stimulate the host immune response to effectively eliminate T. gondii and lessen the host's inflammatory reaction. Conclusions: XYP1-18 had lower cytotoxicity and hemolysis activity than XYP1, as well as significantly extending the survival time of the mice. XYP1 played a role in host inflammation and immune responses, revealing its potential mechanism. Our research provided valuable insights into the development and application of peptide-based drugs, offering novel strategies and directions for treating toxoplasmosis. [ABSTRACT FROM AUTHOR]

AbstractThis study investigated the effects of laser energy density at different scanning speeds on the microstructure evolution, phase equilibrium, mechanical properties, and fracture modes of welds in dissimilar steel welded joints (Q345D and 20Mn2). The connection of dissimilar steel welded joints is achieved by using a laser synchronous powder feeding method. The microstructure and phase evolution of the joint were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Mechanical property testing was performed on the joint via a micro-Vickers hardness tester and an electronic testing machine, and the fracture surface morphology was observed via a scanning electron microscope. The results show that when the laser energy density is 1125 J/mm2, the fine cellular crystals, columnar crystals, and equiaxed crystal structures of the joint are more uniformly distributed. As the laser energy density increased, the transition of the Q345D side structure from cellular to columnar crystals and the transition of the 20Mn2 side structure from cellular to equiaxed crystals became more pronounced. Mechanical property testing revealed that an increase in the laser energy density can significantly improve the microhardness and tensile strength of a joint. However, a large amount of the Fe matrix from the 20Mn2 side permeates into the coating, making the mechanical properties of the dilution zone lower than those of the crystallization zone, and making it more prone to fracture on this side. The fracture analysis results show that the fracture mode has strong ductility, and the fracture mode is judged to be ductile fracture. [ABSTRACT FROM AUTHOR]

Scanning Electron Microscope (SEM) is a crucial tool for studying microstructures of ceramic materials. However, the current practice heavily relies on manual efforts to extract porosity from SEM images. To address this issue, we propose PSTNet (Pyramid Segmentation Transformer Net) for grain and pore segmentation in SEM images, which merges multi-scale feature maps through operations like recombination and upsampling to predict and generate segmentation maps. These maps are used to predict the corresponding porosity at ceramic grain boundaries. To increase segmentation accuracy and minimize loss, we employ several strategies. (1) We train the micro-pore detection and segmentation model using publicly available Al2O3 and custom Y2O3 ceramic SEM images. We calculate the pixel percentage of segmented pores in SEM images to determine the surface porosity at the corresponding locations. (2) Utilizing high-temperature hot pressing sintering, we prepared and captured scanning electron microscope images of Y2O3 ceramics, with which a Y2O3 ceramic dataset was constructed through preprocessing and annotation. (3) We employed segmentation penalty cross-entropy loss, smooth L1 loss, and structural similarity (SSIM) loss as the constituent terms of a joint loss function. The segmentation penalty cross-entropy loss helps suppress segmentation loss bias, smooth L1 loss is utilized to reduce noise in images, and incorporating structural similarity into the loss function computation guides the model to better learn structural features of images, significantly improving the accuracy and robustness of semantic segmentation. (4) In the decoder stage, we utilized an improved version of the multi-head attention mechanism (MHA) for feature fusion, leading to a significant enhancement in model performance. Our model training is based on publicly available laser-sintered Al2O3 ceramic datasets and self-made high-temperature hot-pressed sintered Y2O3 ceramic datasets, and validation has been completed. Our Pix Acc score improves over the baseline by 12.2%, 86.52 vs. 76.01, and the mIoU score improves from by 25.5%, 69.10 vs. 51.49. The average relative errors on datasets Y2O3 and Al2O3 were 6.9% and 6.36%, respectively. [ABSTRACT FROM AUTHOR]

This study aims to produce cadmium selenium (CdSe) thin films with a hexagonal structure using the chemical bath deposition (CBD) method. In this study, 0.075 g of cadmium chloride (CdCl2) is used as a Cd source, 0.06 g of etilendiamin tetra acetic acid [(EDTA), (C10H16N2O8)] as a complexing agent, and 0.1 g of selenourea [CSe(NH2)2] as a selenium source. Ammonia (NH3) is employed to adjust the pH value of the solutions and varying amounts of Na2SO3 (from 0.1 to 1.6 g) are used as a reducing agent. This chemical combination has been used for the first time to produce CdSe thin films. X‐ray diffraction (XRD) results confirm that CdSe thin films exhibit a hexagonal structure without requiring annealing. The energy band gap values calculated via absorption graphs range from 1.76 to 1.91 eV. The surface morphologies are examined using scanning electron microscope (SEM) images. SEM images show that there are no voids, cracks, or pinholes. The software named ImageJ is used to determine surface roughness, showing range from 6 to 8 nm. The photographs of the samples show that some films adhere homogeneously to the surfaces of substrates, depending on the amount of Na2SO3 used. [ABSTRACT FROM AUTHOR]

Transparent lithium aluminum silicon glass‐ceramics are prepared via heat treatment and the effect of boron oxide (B2O3) content on the structure and properties of Li2O‐Al2O3‐SiO2 glass‐ceramics is investigated. The X‐ray photoelectron spectroscopy results reveal that the parent glass containing B2O3 exhibits a higher concentration of bridging oxygen (BO). With an increase in B2O3 content, the relative amount of BO changes from 76.64% to 79.86% and then to 79.52%. Simultaneously, the second crystallization peak temperature TP2 of the samples increases from 715°C to 720°C and then to 724°C by differential scanning calorimeter analysis. The X‐ray diffractometer and scanning electron microscope results indicate that the addition of B2O3 facilitates grain growth, while an increase in B2O3 substitution for Al2O3 hinders the precipitation of LiAlSi4O10 but promotes quartz formation. The glass containing 2 wt% B2O3 with the heat treatment of 560°C/ 4 h+ 680°C/2 h shows a Vickers Hardness value of approximately 7.75 GPa, and a transmittance at 550 nm reaching ∼85%. [ABSTRACT FROM AUTHOR]