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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]

In the current investigation, zinc oxide (ZnO) nanoparticles and Fe-doped ZnO nanoparticles were sustainably synthesized utilizing an extract derived from the Rumex dentatus plant through a green synthesis approach. The Scanning electron microscope (SEM), X-ray diffraction (XRD), Energy-dispersive x-ray spectroscopy (EDX), Ultra-violet visible spectroscopy (UV–vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA) techniques were used to examine the compositional, morphological, optical, and thermal properties of both samples. The doping of iron into ZnO NPs has significantly influenced their properties. The analysis firmly established that both ZnO NPs and Fe-doped ZnO NPs have hexagonal wurtzite structures and spherical shapes by XRD and SEM. The EDX analysis suggests that iron atoms have been successfully integrated into the ZnO lattice. The change in color observed during the reaction indicated the formation of nanoparticles. The UV–vis peaks at 364 nm and 314 nm confirmed the presence of ZnO NPs and Fe-doped ZnO NPs, respectively. The band gap of ZnO NPs by Fe dopant displayed a narrowing effect. This indicates that adding iron ions to ZnO NPs offers a control band gap. The thermal study TGA revealed that Fe-doped ZnO NPs remain stable when heated up to 600 °C. The antibacterial efficacy of ZnO NPs and Fe-doped ZnO NPs was evaluated against several bacterial strains. The evaluation is based on the zone of inhibition (ZOI). Both samples exhibited excellent antibacterial properties as compared to conventional pharmaceutical agents. These results suggest that synthesizing nanoparticles through plant-based methods is a promising approach to creating versatile and environmentally friendly biomedical products. [ABSTRACT FROM AUTHOR]

Additive manufacturing of components with enhanced characteristics to combine the geometrical flexibility of layer-by-layer manufacturing and the remarkable thermomechanical and optical properties of advanced materials has become a focus for research in the last decades. In this investigation, in-house developed Al 2 O 3 slurries mixed with either MgO or MgAl 2 O 4 were digitally light processed and the resulting green parts underwent slow thermal debinding at low heating rates to produce dense and stable brown samples, which were subsequently subjected to different sintering regimes to obtain translucent samples. Air sintering trials were conducted at 1700 °C and the effect of different heating rates and holding times at the sintering temperature were investigated. In addition, vacuum sintering at 1600 °C was conducted for the best conditions to assess the effect of an oxygen-reduced atmosphere. Geometrical dimensions and density data were collected at the brown and fired stages to observe their evolution through the process with the help of high-magnification optical microscopy. Scanning electron microscope (SEM) images of the sintered samples were collected to observe and characterise the obtained microstructure. In addition, X-ray diffraction (XRD) was used to identify the crystal structure and assess the insurgence of secondary phases. Finally, total transmittance and in-line transmittance were measured to evaluate the translucency level achieved by the produced sintered samples. Translucent alumina samples exhibiting a maximum total transmittance of 90.4% and a maximum real in-line transmittance (RIT) of 16.9% in the visible and near-infrared regions were fabricated. [ABSTRACT FROM AUTHOR]

NiSi–NiCr thin film thermocouples (TFTCs) have significant application value as contact temperature sensors in cutting temperature measurements owing to their fast response and negligible volume. However, due to the relatively high chemical activity of Ni-based alloys, high-temperature oxidation strongly affects the operational reliability of NiSi–NiCr TFTCs. In this respect, depositing an anti-oxidation coating onto the surface of NiSi–NiCr TFTCs is considered an effective way to protect them in high-temperature environments. In this study, NiSi and NiCr films were deposited on cemented carbides and annealed at 200 °C–600 °C in air. Scanning electron microscope, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and four-probe resistivity tests were used to characterize the microstructure and resistivity of NiSi and NiCr film. Then SiN x O y films were deposited onto the NiSi and NiCr films and compared with uncoated samples after annealing at 600 °C. The effect of SiN x O y films on the thermal stability and thermoelectric output of NiSi–NiCr TFTCs was investigated. The results show that the NiSi film was partially oxidized at 200 °C and entirely oxidized when the temperature exceeded 400 °C. The completely oxidized NiSi films had evident defects and cracks, and the resistivity increased by a factor of over 1000. The NiCr film could not be completely oxidized at 600 °C, which is attributed to the formation of Cr 2 O 3 as an external oxide barrier layer. Below 600 °C, SiN x O y films could effectively protect NiSi and NiCr films from oxidation. Thus, the addition of SiN x O y film increases the maximum temperature at which NiSi–NiCr TFTCs can be used. [ABSTRACT FROM AUTHOR]

This work's main objective is to assess the effects of wollastonite/fluorapatite glass (G) and glass-ceramic (GC) on tricalcium silicate's (TCS) bioactivity and physico-mechanical properties. To achieve this goal, 10 and 20 wt percent of G or GC were used in place of TCS. The constructed specimens were kept submerged in SBF solution for 4 weeks at a temperature of approximately 37 ± 0.5 °C to create the hydroxyapatite layer (HA) on the cement paste surface and evaluate their biological behavior. Additionally measured were bulk density, apparent porosity, and compressive strength. The principal components had been studied using X-ray diffraction and Fourier transform infrared spectroscopy. An energy dispersive spectroscopy (EDS)-equipped scanning electron microscope (SEM) was used to examine the materials' morphology. The antibacterial and cytotoxic properties were also evaluated. The findings demonstrated that during soaking in SBF, bulk density and porosity ranged from 1.38 to 1.5 g/cm3 and from 44.99 to 39.12 %, respectively, and the results for compression strength varied from 65 to 88 MPa. The outcomes demonstrated that all of the prepared samples' surfaces had the hydroxyapatite layer (HA) formed on them following their immersion in the biological fluid (SBF). Additionally, it was discovered that raising the percentage of GC (TCS/20GC) in synthetic samples improves TCS cement's physico-mechanical and bioactivity characteristics. Furthermore, these substances had minimal cytotoxic effects on the typical fibroplast cell line of humans (BJ1), indicating their potential utility in dental applications. Ultimately, the antimicrobial test demonstrated good inhibitory behavior against the pathogens Bacillus cereus, Staphylococcus aureus, and Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a kind of polyester from biomass. To increase the ductility of PLA, melt blending was used to prepare the polylactic acid/poly(butylene diglycolate) blends in this study. The effect of poly(butylene diglycolate) (PBD) on the thermal, crystallization, tensile, and dynamic mechanical properties of PLA was investigated. The blend containing 30 wt% PBD has a substantially improved elongation at break (79%) due to the lower glass transition temperature of PBD compared to PLA. The results indicated that PLA and PBD exhibited partial compatibility, which was confirmed by dynamic mechanical analysis (DMA) and scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) analysis showed there is the interaction between PLA and PBD. In summary, the incorporation of PBD resulted in improved mechanical properties, indicating potential for applications requiring enhanced ductility. [ABSTRACT FROM AUTHOR]

There have been continuous efforts to further promote various properties of polymeric materials to meet various industrial demands, especially in the area of thermal, electrical, mechanical and wear properties. This study developed polyvinylidene fluoride (PVDF)-boron nitride (BN) nanocomposites and significantly enhanced their wear and nanomechanical properties by incorporating very low content of carbon nanotubes (CNT). The nanocomposites were developed via simple technique of solution mixing and hot compression. Scanning electron microscope showed that the nanocomposites achieved uniform microstructure with no significant agglomeration of the nanoparticles in the PVDF matrix. The wear rate of PVDF-10wt%BN-0.1wt%CNT was reduced from 5.68 × 10–4 and 5 × 10–3 mm3/Nm for pure PVDF to 1.6 × 10–6 and 8 × 10–6 mm3/Nm at applied loads of 10 N and 20 N, respectively. Also, an increase in hardness and elastic modulus of 225% and 219% for PVDF-10wt%BN-0.1wt%CNT was obtained relative to the pure PVDF at 100-mN applied load. While the nanocomposite showed about 75% and 103% increments compared to PVDF-10wt%BN at 100 mN. This study revealed that the addition of small amount of CNT could further improve the wear and mechanical properties of PVDF-BN as well as any other polymer-ceramic binary systems various advanced engineering applications. [ABSTRACT FROM AUTHOR]

At present, the use of isocyanate adhesives mostly requires the assistance of solvents, which can cause adverse environmental pollution and health effects. The aqueous isocyanate avoids the shortcomings of the solvent, but shortens the working life of the isocyanate. Isocyanate microcapsules can avoid these shortcomings, and can also solidify isocyanate to improve the efficiency of isocyanate use. In this study, microencapsulation technology was used to protect the highly reactive -NCO group, improve the stability of isocyanate, and prolong the working life of isocyanate in water-based wood adhesives. That is, isocyanate microcapsules with gum Arabic/gelatin as shell and isocyanate as core were prepared in oil-in-water emulsion by complex coacervation. In addition, the preparation process was optimized by changing the parameters. Then, the prepared isocyanate microcapsules were characterized and analyzed by Fourier transform infrared spectrometer, Scanning electron microscope, Particle size analyzer, etc. Finally, plywood was prepared by using the prepared isocyanate microcapsules in the wood adhesive. The results showed that, the particle size of isocyanate microcapsules was controllable, and the content of active groups and core in the prepared isocyanate microcapsules can reach a high level. The isocyanate microcapsules extend the working life of isocyanates from about 30 mins to 5 hours, and significantly improve the stability of isocyanates. The bonding strength of the prepared plywood meets the requirements of (Class I plywood) with only 20% -NCO addition. [ABSTRACT FROM AUTHOR]

This work aims to modify the surface characteristics of cerium oxide (ceria, CeO 2) nanoparticles using different surface modification strategies for improved CeO 2 nanoparticle dispersion and suspension stability. Analysis and discussion were conducted on the two surface modification processes used by a cationic surfactant like hexadecyl cetyltrimethylammonium bromide (CTAB) and a silane agent like tetraethyl orthosilicate (TEOS). Untreated CeO 2 was used as reference material. The dispersion effect of surface-modified CeO 2 nanoparticles at different pHs was determined by zeta potential measurements. Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Particle size analysis (PSA), Thermogravimetric analysis (TGA), Scanning electron microscope (SEM), Brunauer–Emmett–Teller analysis (BET), and X-ray diffraction (XRD) were used to confirm the efficacy of the surface modification of CeO 2 nanoparticles. First, the results obtained in this experimental work demonstrate that both advanced modifications greatly enhance the dispersion and suspension stability of surface-modified CeO 2 nanoparticles in comparison with untreated CeO 2 nanoparticles. Second, it is also shown that the surface-modified CeO 2 nanoparticles obtained through a silanization surface process with TEOS silane agent had a better dispersion effect and dispersion stability than the surface-modified CeO 2 nanoparticles obtained by surface modification with CTAB cationic surfactant. These results can help better understand how advanced surface modifications can assist the application of well-dispersed CeO 2 nanoparticles in technological applications. [Display omitted] • Surface modification significantly improved the aqueous dispersion and stability of CeO 2 nanoparticles. • The modification improved the CeO 2 dispersion by increasing the spacing and negative charge. • CeO2 dispersion was optimal at a specific pH, with a significant effect of pH. • The modification strategy is crucial for the performance of CeO 2 in technological applications. [ABSTRACT FROM AUTHOR]

Light‐cured polymer composites incorporating particle reinforcements have been adopted for a wide range of engineering applications. Nevertheless, micro‐filled composites exhibit insufficient strength despite good abrasion resistance. Conversely, nano‐filled counterparts possess enhanced strength but easily generate particle agglomeration. Hybrid filling has therefore been utilized in previous studies to combine the advantages of different components, but conclusive results have not been obtained. Within this study, the effects of hybrid filling on the strengthening mechanism and curing kinetics of light‐cured polymer composites were investigated by multi‐scale mechanical tests, in‐situ near‐infrared spectroscopy, scanning electron microscope, and finite element simulations. It was found that hybrid filling led to an average increase in Young's modulus by ~3.94%, the hardness by ~5.81%, the tensile strength by ~10.44%, and the degree of conversion by ~2.54% compared to micro‐filling at the same filler content. Besides, hybrid filling showed more reduced particle agglomeration compared to nano‐scale filling. Finite element analysis revealed that hybrid filling effectively enhanced the load‐bearing capacity of the matrix. Overall, the experimental results unveil a mechanism of particle reinforcement that can be extrapolated to various particle‐filled polymers across different length scales. These findings provide a versatile manufacturing technique for composites with heightened mechanical reinforcement and are expected to guide the application in the field of photo‐polymeric materials. Highlights: Light‐cured polymer composites incorporating hybrid silica particles were prepared.The strengthening mechanism was investigated by multi‐scale mechanical tests.Hybrid filling could lead to an increase in material strength compared to micro‐filling.Hybrid filling exhibited reduced particle agglomeration in comparison to nano‐filling. [ABSTRACT FROM AUTHOR]

Single Chain Variable Fragment (scFv), a small fragment of antibody can be used to substitute the monoclonal antibody for diagnostic purposes. Production of scFv in Escherichia coli host has been a challenge due to the potential miss-folding and formation of inclusion bodies. This study aimed to express anti-CHIKV E2 scFv which previously designed specifically for Asian strains by co-expression of three chaperones that play a role in increasing protein solubility; GroEL, GroES, and Trigger Factor. The scFv and chaperones were expressed in Origami B E. coli host under the control of the T7 promoter, and purified using a Ni-NTA column. Functional assay of anti-CHIKV-E2 scFv was examined by electrochemical immunosensor using gold modified Screen Printed Carbon Electrode (SPCE), and characterized by differential pulses voltammetry (DPV) using K3[Fe(CN)6] redox system and scanning microscope electron (SEM). The experimental condition was optimized using the Box-Behnken design. The results showed that co-expression of chaperone increased the soluble scFv yield from 54.405 μg/mL to 220.097 µg/mL (~5×). Furthermore, scFv can be used to detect CHIKV-E2 in immunosensor electrochemistry with a detection limit of 0.74048 ng/mL and a quantification limit of 2,24388 ng/mL. Thus, the scFv-anti-CHIKV-E2 can be applied as a bioreceptor in another immunoassay method. [ABSTRACT FROM AUTHOR]

In this paper, polyacrylamide (PAM) was used as the main matrix material to form the first layer network structure, and polyvinyl alcohol (PVA) was used as the secondary matrix material to form the second layer network structure. The hydrogels were prepared by free radical in‐situ polymerization and physical cross‐linking. This hydrogel was characterized not only by its semi‐interpenetrating network structure, in which cellulose nanocrystals (CNC) penetrate through the polyacrylamide network but also by the physically and chemically cross‐linked hybrid PAM/PVA double network. The structure and appearance of the hydrogels were characterized by scanning electron microscope and Fourier transform infrared spectrometer, and a series of tests were carried out to detect their mechanical properties, electrical properties and sensing properties. The results show that the hydrogel has good mechanical properties (the elongation at break can reach 600 % and the stress at break can reach 0.16 MPa), and the hydrogel also has good sensing and electrical properties. The addition of organic solvents makes the hydrogels have excellent antifreeze and water retention properties and also have excellent swelling properties. Therefore, the PAM/PVA/CNC dual network interpenetrating composite hydrogel has potential application value in the field of flexible sensors. [ABSTRACT FROM AUTHOR]

Background: Heterakis gallinarum (H. gallinarum) is a common poultry parasite that can be found in the ceca of many gallinaceous bird species, causing minor pathology and reduced weight gain. Most infections go unnoticed in commercial flocks due to the dependence on fecal egg counts, which are prone to false-negative diagnoses. Furthermore, there is a lack of research on gastrointestinal nematodes that use molecular identification methods, which could be essential for rapid diagnosis and developing efficient control approaches. As a result, the study aimed to look at the cause of mortality in layer chickens induced by H. gallinarum in Egyptian poultry farms using morphological, ultrastructural, and molecular characterization. Histopathological, immunohistochemical, and cell-mediated immune responses from damaged cecal tissues were also examined. Results: Seventy bird samples from ten-layer flocks of different breeds (Native, white, and brown layers) suffering from diarrhea, decreased egg output, and emaciation were collected. Cecal samples were collected from affected and non-affected birds and were examined for parasitic diseases using light and a scanning electron microscope. The mitochondrial cytochrome oxidase 1 (COX1) gene was used to characterize H. gallinarum. Our results showed that the collected nematodal worms were identified as H. gallinarum (male and female), further confirmed by COX1 gene amplification and sequence alignment. Gene expression analysis of the inflammatory markers in infected tissues showed a significant up-regulation of IL-2, IFN-γ, TLR-4, and IL-1β and a significant down-regulation of the anti-inflammatory IL-10. The mRNA level of the apoptotic cas-3 revealed apoptotic activity among the H. gallinarum samples compared to the control group. Conclusions: Our results implemented the use of molecular methods for the diagnosis of Heterakis, and this is the first report showing the tissue immune response following infection in layers: upregulation of IL-1β, IFN-γ, Il-2, and TLR-4, while down-regulation of anti-inflammatory IL-10 in cecal tissue, Cas-3 apoptotic activity and Nuclear factor-κB (NF-κB)activity with immunophenotyping of T-cells in Heterakis infected tissue. [ABSTRACT FROM AUTHOR]

Roll bonding is a solid-state welding process, employed to join similar and dissimilar metals. Roll bonding with secondary particles in-between and accumulating the roll bonded material multiple times is an alternative method for manufacturing high-strength composites. In the current work, commercially pure aluminium strips are roll bonded at room temperature to 400 °C. The percent reduction varied from 10% to 70%, with an increment of 10%. Moreover, the aluminium strips are roll bonded with graphite particles dispersed in between (Al–Gr–Al). The aim is to study the effect of graphite particles on bonding behaviour. The critical process parameters such as the effect of temperature and percentage reduction on the bond strength are determined. The lap shear test is used to evaluate the bond strength. It is observed that the dispersion of graphite particles in between aluminium significantly increased the threshold reduction required for bond establishment. The threshold reduction decreases for roll-bonding aluminium with increasing temperature. Furthermore, it is observed that the bond strength significantly increases with increasing processing temperature. However, roll bonding with the graphite particles dispersed in between reduced the bond strength, and the effect was significant with increasing temperature. The bond strength of both Al and the Al–Gr–Al composites increases by increasing the reduction percentage. The de-bonded sample surfaces are analyzed using a scanning electron microscope. It is worth mentioning that the experimental outcomes of the current study predict the roll bonding parameters for the successful fabrication of an Al/Gr composite by accumulative roll bonding. [ABSTRACT FROM AUTHOR]

We developed an intelligent device capable of controlled release of anti-cancer drugs. The nano-carrier consists of two key components: firstly, magnetic nanoparticles were synthesized through co-precipitation and then functionalized for attaching anti-cancer drugs; secondly, a polymer (poly(N-isopropylacrylamide-co-acrylic acid)) sensitive to pH and temperature was synthesized and employed to encapsulate the drug-loaded magnetic nanoparticles. This responsive polymer exhibits a lower critical solution temperature (LCST) of 38.5 °C, indicating a phase transition behavior. Numerous techniques and analyses, including Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potentials, scanning electron microscope, and transmission electron microscopy, were employed to confirm the successful execution of the aforementioned process. In vitro release assessments of the anti-cancer drug, doxorubicin, were conducted across various media (pH 5–8 and temperatures ranging from 20 to 40 °C). The outcomes revealed higher drug releases at temperatures exceeding the LCST (40 °C) and at slightly acidic pH levels (5–5.3). Notably, compared to the effectiveness of the unloaded drug, the magnetic smart polymer loaded with DOX exhibited a more potent cytotoxic effect. Considering these results, this nano-carrier emerges as a promising candidate for targeted therapeutic delivery to cancerous tissues. [ABSTRACT FROM AUTHOR]

The design, simulation, and beam dynamics analysis of the integrated illumination system of the scanning electron microscope (SEM) have been reported. The dimensions and capacity of the SEM components, such as the electron gun, electron column, and lenses, were determined using the finite element method. The optimization of the illumination system was performed, and characteristics beam parameters were studied analytically. The gun consisted of a simple diode structure having; cathode, Wehnelt, and anode electrodes. A tungsten cathode of diameter 150 μm was used to emit the electrons thermionically. The electrons beam was generated at 2700 K with acceleration potential of 15 kV. Pair of electromagnetic lenses producing field strengths, 221 mT and 253 mT, respectively, focused the beam at 56.5 mm from cathode, with beam diameter of 9 μm in the post anode region. The calculated value of beam brightness was 2.97 × 106 A/(mm-rad)2. The final beam spot thus obtained was stable and perfectly symmetric along the two transverse directions. Gun assembly and lenses are thermally stable at the operational temperature. The illumination system geometry offers full-beam collimation control with reduced column length, making it suitable for electron diffraction studies, where focusing of the beam onto a sample is desired. [ABSTRACT FROM AUTHOR]

Traditional methods of pest control are not able to prevent crop damage due to devastating pests. Therefore, through nanobiotechnology nano-bio pesticides and conjugated nanoparticles are produced as a pest control agent. The present work focused on the synthesis, characterization of silver nanoparticles (AgNPs) using Ocimum tenuiflorum leave extract and its larvicidal activity against Helicoverpa armigera. AgNPs were characterized by UV–Vis spectral analysis, indicated an absorbance of 4.695 at 560 nm. Moreover, Scanning Electron Microscope and X-ray Powder Diffraction showed that particles were spherical, ranging from 10 nm to 65 nm. The larvae of H. armigera were provided with an artificial diet with AgNPs coating of 0.25%, 0.5%, 0.75%, and 100% pure concentration. After 24 h, a dose response relationship in mortality was found maximum in pure AgNPs treated group, 83.33% and 75% in 0.75% treated group and 0.5% treated group, respectively. While the least mortality of 50% was observed in the 0.25%, AgNPs treated group. The LC50 calculated was 20.33 µL for AgNPs. It can be concluded that silver-nanoparticles possess a larvicidal effect. Furthermore, the biosynthesis of these particles is an efficient and profitable approach. [ABSTRACT FROM AUTHOR]

In order to solve the problem of poor stability of HPAM (partially hydrolyzed polyacrylamide) gel as a plugging agent at 150 °C, this paper investigates the preparation of a polymer gel strengthened with nano-SiO2, exhibiting good thermal stability, using a low-cost, low-hydrolysis anionic polymer. The experimental results indicated that when the gel was prepared with 1 wt% HPAM, 1 wt% water-soluble phenolic resin (WSPR) as a crosslinker, and 1 wt% nano-SiO2 as a stabilizer, the dehydration rate of the gel was less than 5 wt% after 180 days of aging at 150 °C. In order to identify the stability mechanism of nano-SiO2-strengthened polymer gel, we conducted rheological tests, Cryo-SEM analysis, Fourier transform infrared (FTIR) spectroscopy, and solid-state nuclear magnetic resonance (NMR) analysis on the polymer gel before and after adding nanoparticles. The methods described in the study demonstrate the excellent long-term thermal stability of the polymer gel strengthened with nano-SiO2 from both chemical bonding and microscopic perspectives. The results of rheological experiments indicated that the addition of nanoparticles improved the yield stress and long-term thermal stability of the gel. The scanning electron microscope (SEM) microstructure analysis confirmed that the addition of nanoparticles resulted in high-density cavities between the microscopic network structures of the gel. This facilitated the trapping of a significant amount of free water and the formation of a stable spatial mechanical support structure, ultimately enhancing the macro-mechanical strength of the gel. Additionally, FTIR and NMR experiments demonstrated that the nanoparticles effectively inhibited the hydrolysis of amide groups to carboxylate, thereby significantly preventing the high-temperature degradation of the gel and maintaining its strength after prolonged aging. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to offer an effective nanocomposite for potential use to consolidate and protect deteriorated archaeological pottery. Design/methodology/approach: Three nanocomposites were used in the experimental study. This study used nano Primal AC33, silicon dioxide (SiO2) and montmorillonite (MMT) nanoparticles to protect and consolidate pottery specimens. Pottery specimens were made at 800°C for this investigation. Consolidation materials were applied with a brush. The properties of the treated pottery specimens were assessed using several methods such as digital and scanning electron microscopes, static water contact angle, color alteration, physical properties and compressive strength. Findings: Microscopic examination indicated the ability of the nano Primal AC33/MMT nanocomposites to cover the outer surface well and bind the inner granules. Concerning specimens with code F treated with nano Primal AC33 5%/MMT 3% nanocomposites, it achieved an increase in contact angle (120°), density (1.23 g/cm3) and compressive strength (561 kg/cm2), as well as a decrease in color change (ΔE = 2.62), water absorption (4.45%) and porosity (5.46%). The novelty of the results is due to the characteristics of nano Primal AC33 5%/MMT 3% nanocomposites used in the current study. Originality/value: This study describes the significant results of the analytical methods used for evaluating consolidation materials used in this study. The findings offer useful information for the protection of archaeological pottery. The investigation indicated that nano Primal AC33 5%/MMT 3% nanocomposites gave the best results. Therefore, it is recommended to use this nanocomposite to consolidate archaeological pottery. As a result, the current work provides a promising first step in conserving archaeological pottery for future studies. [ABSTRACT FROM AUTHOR]

Herein, a green synthesis methodology for making copper oxide (CuO) nanoparticle clusters in a cost-effective and simple way is reported. While cuprous sulfate pentahydrate is used as a source of copper, the outer layer of green peas (Pisum Sativum) is used as a source of phenol. Extracting the phenol from pea peels is a simple process that uses water as a solvent. Copper salt is reduced by the phenolic content that is so produced. Both physicochemical and microscopic characterization Scanning Electron Microscope (SEM), and Energy-dispersive X-ray (EDX) analysis were performed on the particles. A variety of pea-peeling samples were used during the procedure's several executions to ensure reproducibility. The preparation process was appropriate, as the outcomes were identical. Analyses were also conducted on the produced particles' electrochemical activity as an application. A well-defined and organized redox reaction was seen at E' = +0.25 V against Ag/AgCl which were also shown to be highly electro-active. With the benchmarked redox mediator (5 mM ferricyanide), the particles also produced an outstanding redox peak at E1/2 = -0.01 V vs. Ag/AgCl. In a common reducing organic reaction, such as the reduction of p-nitro phenol to p-amino phenol, they were also found to be effective catalysts. Additionally, tests were conducted on the produced particles for their anti-bacterial and antifungal properties. Overall, a simple method for the formation of commercially viable CuO nanoparticle clusters is developed with the potential for diverse applications. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the mechanical characteristics and application of e-waste as a filler for glass fiber composites made of S and E (e-waste + S E). Metal, printed circuit boards, integrated circuits, diodes, and transistors were separated from the e-waste filler during milling. S and E glass fiber, epoxy, and filler were utilized in proportions of 10%, 10%, and 70%, respectively, on a volume basis. The hand lay-up technique was used to construct composite specimens. Scanning electron microscope analysis was used to gauge how filler loading affected the morphology of composite materials. The composite has a compressive strength of 23.760 MPa, which is 69.71% higher than the Geo poly composite. The tensile strength of this composite is withstood up to 16.078 MPa. It has 53% better tensile properties than Sunflower Husk composites with the same operating conditions. It gives a resistance up to 42 D during hardness test to withstand. It was 15.6% better than the NF30% epoxy composite specimen. The e-waste + S E composite gives a great opposite force of up to 2 kJ on the impact load test.; it was 86.9% higher than fly ash epoxy composites. [ABSTRACT FROM AUTHOR]

The objective of this study was to optimize the fermentation parameters by using response surface methodology for increasing pullulan production of Aureobasidium pullulans AZ-6 in synthetic fermentation medium. The optimum conditions were determined as follows: the initial sucrose concentration (X1): 100 g/L; the initial peptone concentration (X2): 11.31 g/L; the initial pH (X3): 6.48; and the temperature (X4): 24.2 °C. In the optimum conditions, the maximum exopolysaccharide (EPS) concentration (Y1), the maximum pullulan concentration (Y2), the specific growth rate (Y3), the maximum specific pullulan formation rate (Y4), and the pullulan yield (Y5) were expected to be obtained as 37.078 and 35.372 g/L, 0.062 h−1, 0.021 [g pullulan/(g mo.h)], and 53.681%, respectively. The observed values of Y1, Y2, Y3, Y4, and Y5 were 36.950 g/L, 35.470 g/L, 0.064 h−1, 0.036 [g pullulan/(g mo.sa)], and 54.480%, respectively, as a result of validation experiments. EPS samples were characterized by Fourier-transform infrared spectroscopy and scanning electron microscope analyses. The optimization process caused more than a 50% increase in EPS and pullulan concentrations. This study showed that the color-variant A. pullulans AZ-6 strain could become a significant industrial strain if it is explored further in the future to produce pullulan on a larger scale. [ABSTRACT FROM AUTHOR]

With the increasing popularity of fused deposition modelling (FDM), an improved understanding of the interdependence between process-structure-property (P-S-P) of FDM manufactured (FDMed) parts is imperative. This paper proposes models for linking the microstructure and degradation of properties during the FDM process with the mechanical properties. Through careful and elaborate finite element (FE) modeling, it is demonstrated that there is definite material degradation during the FDM process, which cannot be attributed only to extra voids generated during printing. A novel hybrid multiscale model is proposed to estimate the degradation parameter and utilize this information to predict the printed coupons' properties. Additionally, two methods for generating representative volume element (RVE) are demonstrated using scanning electron microscope (SEM) imaging and density data. For the experimental validation, polyamide (PA) and polylactic acid (PLA) filaments and dogbone samples with multiple raster orientations were tested. The use of degradation parameter during modeling leads to very accurate results for both PLA and PA. Also, it presents insights into the limitations of the FDM process and possible improvements. [ABSTRACT FROM AUTHOR]

Ni 1-x Ag x O nanoparticles (NPs) with x = 0.00, 0.02, 0.04, 0.06, and 0.08) were fabricated using the composite hydroxide mediated (CHM) method. The effects of Ag doping on the structural, magnetic, and antimicrobial characteristics of NiO NPs have been reported. The stretching mode of the Ni–O molecules was identified at 443 cm−1 in the Fourier transform infrared spectra. The aggregation of nanoparticles with different sizes and shapes is seen under transmission and scanning electron microscopes. The blocking temperature (T B) peak in zero-field cooled (ZFC) magnetization curves display the magnetization from the core of NPs. This peak is absent for the samples with x = 0.00 and 0.02 , which show instead a small net magnetization from the antiferromagnetic core of these NPs. However, a T B peak was found for the samples with x = 0.04 , 0.06 and 0.08 , at 22, 72, and 65 K, respectively, which indicates that the magnetization is induced from the AFM core of NiO NPs for higher Ag doping. With an increasing concentration of Ag in the NiO NPs, the net magnetization did increase and a maximum was found for x = 0.04 at 300 K. For a higher doping concentration of 8 % Ag, a sharp decrease in magnetization was observed. Furthermore, the efficacy and synergistic effect of Ag doping had been analyzed for the effective improvement of the antibacterial properties of NiO NPs. Pure and Ag-doped NiO NPs were exploited to assess their anti-microbial activity against Enterobacter sp., E. coli, P. aeruginosa, and S. pyrogens. The study revealed that anti-bacterial or anti-biofouling properties were introduced as an additional attribute to NiO NPs by incorporation of Ag ions due to its inherent nature as an antimicrobial agent and enhanced its capability to sterilize microbial pathogens. [ABSTRACT FROM AUTHOR]

In this work, novel Mn2+‐doped transparent NaYP2O7 glass–ceramics were prepared through melt‐quenching and subsequent thermal treatment. The surface crystallization method was confirmed based on the differential scanning calorimeter, X‐ray diffraction, and scanning electron microscope characterization. As the increase and prolong of the heat‐treatment temperature and time, the crystallinity of the NaYP2O7 glass–ceramics increases, while the transmittance gradually decreases. The optimal heat‐treatment regime is identified to be crystallized over 4 h at 580°C based on the crystallinity and transmittance. Under the excitation of 408 nm, both the Mn2+‐doped precursor glass and glass–ceramic crystallized at 580°C for 4 h generate a broad emission at 620 nm (4T2(g)→6A1(s)) with a full width at half‐maximum (FWHM) of ∼107 nm. The glass–ceramics exhibit higher emission intensity and longer decay lifetime than that of precursor glass with the aid of the low phonon energy NaYP2O7 crystals. The Mn2+‐doped glass–ceramic exhibits stable orange‐red luminescence with the chromaticity coordinates of (0.568, 0.428), low correlation color temperature of 1 800 K, high color purity of 98.88%, and low thermal quenching (70% at 373 K of the initial intensity at 298 K). The above results indicate that Mn2+‐doped transparent NaYP2O7 glass–ceramics have promising potential for orange‐red color display devices. [ABSTRACT FROM AUTHOR]

The poor high‐temperature tribological performance of diamond‐like carbon (DLC) films severely limits their applications. To address this issue, silicon (Si) doped DLC films with Si content ranging from 0 to 11.52 at.% were synthesized utilizing the plasma‐assisted reactive magnetron sputtering technique. The influence of Si incorporation on the microstructure and mechanical properties was meticulously investigated by Raman spectroscopy, scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS), nanoindentation, and scratch testing. To ascertain the tribological behavior of the Si‐DLC films under elevated temperature conditions, in situ high‐temperature tests were conducted, spanning temperatures from ambient to 500°C. The findings indicated that distinct lubrication mechanisms prevail for Si‐DLC films with varying Si content across different temperature domains. As the test temperature and Si content increased, the lubrication mechanism exhibited a gradual transitions from high‐temperature induced graphitization to a particle wear regime dominated by SiC and formed SiO2 abrasive phases. The comprehensive performance of the films peaked at a Si content of 4.72 at.%, suggesting an optimal composition for high‐temperature applications. It is postulated that the in‐depth investigation presented herein holds considerable value for the design and fabrication of DLC films intended for use in high‐temperature settings, potentially unlocking their full potential in such demanding environments. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the possible defects and their root causes in a soft-termination multilayered ceramic capacitor (MLCC) when subjected to a thermal reflow process. Design/methodology/approach: Specimens of the capacitor assembly were subjected to JEDEC level 1 preconditioning (85 °C/85%RH/168 h) with 5× reflow at 270°C peak temperature. Then, they were inspected using a 2 µm scanning electron microscope to investigate the evidence of defects. The reliability test was also numerically simulated and analyzed using the extended finite element method implemented in ABAQUS. Findings: Excellent agreements were observed between the SEM inspections and the simulation results. The findings showed evidence of discontinuities along the Cu and the Cu-epoxy layers and interfacial delamination crack at the Cu/Cu-epoxy interface. The possible root causes are thermal mismatch between the Cu and Cu-epoxy layers, moisture contamination and weak Cu/Cu-epoxy interface. The maximum crack length observed in the experimentally reflowed capacitor was measured as 75 µm, a 2.59% difference compared to the numerical prediction of 77.2 µm. Practical implications: This work's contribution is expected to reduce the additional manufacturing cost and lead time in investigating reliability issues in MLCCs. Originality/value: Despite the significant number of works on the reliability assessment of surface mount capacitors, work on crack growth in soft-termination MLCC is limited. Also, the combined experimental and numerical investigation of reflow-induced reliability issues in soft-termination MLCC is limited. These cited gaps are the novelties of this study. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to explore the influence of corrosion-deformation interactions (CDI) on the corrosion behavior and mechanisms of 316LN under applied tensile stresses. Design/methodology/approach: Corrosion of metals would be aggravated by CDI under applied stress. Notably, the presence of nitrogen in 316LN austenitic stainless steel (SS) would enhance the corrosion resistance compared to the nitrogen-absent 316L SS. To clarify the CDI behaviors, electrochemical corrosion experiments were performed on 316LN specimens under different applied stress levels. Complementary analyses, including three-dimensional morphological examinations by KH-7700 digital microscope and scanning electron microscopy coupled with energy dispersive spectroscopy, were conducted to investigate the macroscopic and microscopic corrosion morphology and to characterize the composition of corrosion products within pits. Furthermore, ion chromatography was used to analyze the solution composition variations after immersion corrosion tests of 316LN in a 6 wt.% FeCl3 solution compared to original FeCl3 solution. Electrochemical experiment results revealed the linear decrease in free corrosion potential with increasing applied stress. Electrochemical impedance spectroscopy results indicated that high tensile stress level damaged the integrity of passivation film, as evidenced by the remarkable reduction in electrochemical impedance. Ion chromatography analyses proved the concentrations increase of NO3− and NH4+ ion concentrations in the corrosion media after corrosion tests. Findings: The enhanced corrosion resistance of 316LN SS is attributable to the presence of nitrogen. Research limitations/implications: The scope of this study is confined to the influence of tensile stress on the electrochemical corrosion of 316LN at ambient temperatures; it does not encompass the potential effects of elevated temperatures or compressive stress. Practical implications: The resistance to stress electrochemical corrosion in SS may be enhanced through nitrogen alloying. Originality/value: This paper presents a systematic investigation into the stress electrochemical corrosion of 316LN, marking the inaugural study of its impact on corrosion behaviors and underlying mechanisms. [ABSTRACT FROM AUTHOR]