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This research focuses on synthesizing polyvinyl alcohol (PVA) nanocomposite film adopted with 3–9 wt% of nano-sized (50 nm) titanium dioxide (TiO2) particles through a sol–gel (spin coating) route. Feature of TiO2 nanoparticles on microstructural behaviour is evaluated via scanning electron microscope and X-ray diffraction, and its optical properties like absorption & transmittance, optical band gap, and optical conductivity are studied. Including 9 wt% TiO2 in PVA film shows increased absorption peaks of 220–440 nm, and the transmittance range decreased by 16% compared to pure PVA. In addition, the optical energy band gap decreased from 3.7 to 2.6 eV, and its optical conductivity progressively increased from 0.1 to 1.3 × 1012. [ABSTRACT FROM AUTHOR]

Purpose: Paper aims to evaluate the efficiency of traditional chitosan, nano chitosan, and chitosan nanocomposites for consolidating aged papyrus samples. Cellulose-based materials, such as papyrus sheets and paper, which are the most common types of writing supports for works of art in many museums and archive. They are subjected to different types of deterioration factors that may lead to many conservation problems. Consolidation treatment is one of the most common conservation treatments, which should have perform after much testing to select the appropriate consolidants. Design/methodology/approach: This research paper aims to evaluate the resistance of traditional chitosan, nanochitosan and chitosan/zinc oxide nanocomposite as an eco-friendly papyrus strengthening. Untreated and treated papyrus was thermally aged and characterized via scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). Antimicrobial activity of the papyrus specimens was also determined against four tested pathogenic bacteria by disc diffusion method: MRSA, Staphylococcus aureus, E. coli and P. aeruginosa. Findings: The results revealed that chitosan nanocomposite showed a remarkable enhancement of papyrus tensile properties and presence of ZnO prevents the effects of biodeterioration. Originality/value: Zinc oxide nanoparticles enhance the optical properties and increase the chemical reactions between the consolidating material and the treated papyrus. [ABSTRACT FROM AUTHOR]

In this work, the gas sensing properties of ZnS/Porous silicon heterostructures have been investigated. . Zinc sulfide(ZnS) with high gas sensing performance is successfully synthesized over the Porous silicon substrate by the spray pyrolysis method. The properties of the as-prepared samples were characterized X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform spectrum (FTIR) and optical properties. The results reveal that the properties of the ZnS/Porous silicon heterostructures enhanced when the when the ZnS concentration is increased. The performance ZnS/Porous silicon as a gas-sensing show that the maximum sensitivity is found to be 5.11 at ZnS concentration of 0.5 M and etching time of 15 min compared to the other sensitivities. The ZnS-PSi heterojunction based gas sensor may be used for UV-light photo-detectors due to a valuable properties such as high sensitivity and fast response. [ABSTRACT FROM AUTHOR]

Weight reduction is one of the prime goals for auto industries to achieve fuel economy, and magnesium matrix composite offers the opportunity to assist with fulfilling those needs. The present work focuses on developing the magnesium alloy (AZ91D), AZ91D/SiCnp nanocomposite, and AZ91D/SiCnp/CNT hybrid nanocomposite via the semisolid stir casting technique incorporating the ultrasonic vibration process. The produced cast samples are subjected to physical, microstructural, and mechanical characteristics study. The evaluated results are compared and it was found that AZ91D/6wt% SiCnpnanocomposite offers high hardness (78.45 ± 0.1 Hv), yield (150 ± 1.8 MPa), and ultimate tensile strength (241 ± 1.75 MPa) as compared to the cast AZ91D alloy samples. The scanning electron microscope reveals the homogeneous particle distribution structure with reduced porosity. The density of the developed composite obeys the rule of the mixture, and the porosity is limited to less than 1%. The presence of 6 wt% carbon nanotube in AZ91D/6wt% SiCnp alloy nanocomposite facilitates superior hardness, yield, and tensile strength of 84.35 ± 0.1 Hv, 174 ± 1.5 MPa, and 271 ± 1.6 MPa. The impact strength of the composite increased, while the content of SiCnp was improved. [ABSTRACT FROM AUTHOR]

Sulfuric acid corrosion is a non-negligible problem affecting the durability of concrete materials. To explore the mechanism of sulfuric acid corrosion on the fracture performance and microstructure of concrete, three-point bending test was utilized to analyze the evolutionary characteristics of the crack mouth opening displacement and the fracture toughness of concrete corroded by sulfuric acid. Scanning electron microscope and energy-dispersive spectrometer were utilized to analyze the characteristics of microscopic morphology and corrosion products of concrete corroded by sulfuric acid. The result shows that the fracture evolution of concrete can be divided into four stages: nonlinear development stage, linear development stage, deceleration expansion stage, and accelerated expansion stage. In purified water environment, the peak fracture load and fracture toughness of concrete is positively related to corrosion time. In sulfuric acid corrosion environment, the peak fracture load and fracture toughness of concrete are negatively related to corrosion time and concentrations of sulfuric acid solution. Microscopic experiments show that the interior of concrete is less affected by sulfuric acid corrosion, and the structure is relatively dense compared with the surface. The expansion crystal ettringite formed at the fracture surface of the concrete specimen during sulfuric acid corrosion was the main reason for the durability reduction of concrete. [ABSTRACT FROM AUTHOR]

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

Background: Researchers, prompted by the toxicity and side effects associated with cisplatin, are exploring alternative approaches for developing transition metal-based anticancer agents. Employing a green biochemical approach, we transformed Nickel pyridine dicarboxylic acid compounds into the nanoscale using the aqueous extract of Macrotyloma uniflorum (horse gram). Results: Characterization of the biosynthesized nanoparticles involved electronic and IR spectroscopy. A scanning electron microscope revealed a predominant spherical shape for most Nickel nanoparticles (Ni-NPs), with XRD patterns indicating particle sizes ranging from approximately 30–150 nm. The nanoparticles were evaluated for their free radical scavenging efficiency and in vitro anti-malignant properties against HeLa and A549 cancer cell lines. Numerical optimization of the DPPH and MTT assays was conducted using response surface methodology (RSM), focusing on the effects of 3,4-pyridine dicarboxylic acid (ML1), 2,4-pyridine dicarboxylic acid (ML2), nickel nanoparticles concentration, and temperature. In this investigation, the incorporation of Horse Gram seed extract (Macrotyloma uniflorum) has unveiled its abundance in phenolic and flavonoid compounds, widely acknowledged for their robust antioxidant activity in the existing literature. Conclusion: The present study highlights the potential for refining the bio-toxicity and biochemical attributes of Ni-NPs to pave the way for a new generation of versatile anticancer agents with clinically established efficacy. Notably, the anticipated data closely corresponds with experimental outcomes, reinforcing the trustworthiness and validity of the RSM model for examining anticancer and antioxidant properties in this context. ML2 exhibited heightened antioxidant and anticancer activities in comparison to ML1 nanoparticles. [ABSTRACT FROM AUTHOR]

Background: The intricate textural patterns commonly observed in metamorphosed and recrystallized zircon (ZrSiO4) underscore the crucial necessity of understanding the underlying mechanisms governing their formation to ensure accurate interpretation of the chemical and isotope data they contain. This study employed a combination of microanalytical techniques, including electron backscattered diffraction (EBSD) analysis, electron microprobe (EMP) mapping, and scanning electron microscope (SEM) imaging, to investigate the processes of formation and modification of zircon in a late Pleistocene (~ 35 ka) syenite enclosed within the Nari Tephra Formation on Ulleung Island in South Korea. Findings: Under cathodoluminescence (CL), zircons within the syenite reveal dark, featureless, or oscillatory-zoned cores containing numerous inclusions of britholite. These cores are partially or entirely replaced by inward-penetrating bright-CL domains that exhibit minimal inclusion presence. Despite these changes, the external morphologies of the zircons remain largely unchanged, and the faded oscillatory zoning is preserved in the replaced regions. EMP mapping discloses amoebiform micro-domains with high Y, U, and Th concentrations within the dark-CL cores, while the bright-CL domains are relatively deficient in these trace elements. Microstructural analysis of the zircons using EBSD mapping indicates no significant misorientation between the dark-CL cores and the bright-CL rims. Deformation-related low-angle boundaries by lattice distortion are clearly observed in certain grains, cutting across the discrete SEM and EMP domains, and often aligned along submicron pore trails. Conclusions: Microstructural and microchemical analyses carried out in this study establish that the zircons within the Ulleung syenite have undergone subsolidus recrystallization, a process likely influenced by the presence of fresh melts or fluids. This recrystallization process could be attributed to either coupled dissolution and reprecipitation or thermoactivated particle and defect volume diffusion due to inherent lattice strain. The subsequent deformation observed in the zircons might be a result of increased stress within the magma system after the recrystallization. [ABSTRACT FROM AUTHOR]

The economic spray pyrolysis process were used to prepare Zinc oxide thin films. Ahigh - quality thin film is obtained by optimizing factors that include concentration, flow rate, nozzle to substrate distance. The temperature is differed between 350°C to 450°C. The structural and optical qualities were studied through physical investigation. According to XRD, the films have a hexagonal crystal structure. A scanning electron microscope reveals the material's uniform deposition &adhesion across a glass substrate. A direct band gap of about 2.4 to 2.6 eV was obtained for different temperatures. [ABSTRACT FROM AUTHOR]

In this study, bacterial cellulose (BC) was obtained from Komagataeibacter xylinus S4 and characterized in detail. The effects of a various of carbon sources and media, different pH conditions, incubation temperatures, Surface area/Volume ratios, and incubation durations were determined for BC production. Considering the carbon types, the amount of BC production from high to low was realized as sucrose, fructose, mannitol, xylose, arabinose, and lactose. The highest BC amount (1.303 g/L) was achieved by combining M1A05P5 broth, 30 °C, 1.06 cm-1 Surface area/Volume ratio, pH 3.5 and 21 days. According to scanning electron microscope (SEM) analysis, the cellulose fibril diameters were 34.87-45.97 nm at pH 3.5 and 29.71-102.3 nm at pH 6.5 in M1A05P5. Also, TGA analysis exhibited that the weight loss of BC in the removal of water step initialized between 50 °C and 150 °C and the degradation step initialized between 215 °C and 228 °C. Finally, the electrical conductivity values of the BC samples were determined on the 27-137 °C temperature scale. It was observed that the conductivity was temperature dependent, and the conductivity increased exponentially as the temperature increased. In conclusion, the cellulose from K. xylinus S4 typically showed a semiconducting behavior. [ABSTRACT FROM AUTHOR]

Fábrica de Loiça de Sacavém (ca. 1858–1994) was among the first to produce white earthenware in Portugal, becoming one of the country's leading ceramic manufacturers during the late 19th to early 20th centuries. Research on white earthenware has accompanied the growing interest in post-industrial archaeology but is still poorly explored compared to more ancient ceramic productions. This study focused on the ceramic body, glazes, and colourants of tableware produced by Fábrica de Loiça de Sacavém during the first 50 years of its activity (1859–1910). A multi-analytical approach was selected to investigate the chemical and mineralogical composition of the ceramic body, glaze, and pigments using optical microscopy, variable-pressure scanning electron microscope energy-dispersive X-ray spectroscopy (VP-SEM-EDS), μ-Raman spectroscopy, μ-X-ray Diffraction (μ-XRD), and reflectance spectroscopy (hyperspectral image analysis). The studied tableware was produced with a Ca-poor siliceous–aluminous white earthenware ceramic body covered with transparent alkali lead or lead borosilicate glaze, and most colourants were complex Cr-based pigments. These results are in agreement with the little documental evidence from this period found in the manufacturer's archives. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are ubiquitous and evasive in nature. They can be found in complex agricultural matrices like soil and compost. In the literature, extracting MPs from soil is more prevalent; nonetheless, the same instruments in extraction in soil samples can also be used to assess MPs in compost despite the high levels of organic material. MPs in agricultural environments have recently become a focus of research due to their status as emerging pollutants. However, the lack of standardized instruments and techniques for analysis is a major challenge in assessing MPs. Despite this limitation, this review article identified and suggested some important factors to consider when selecting suitable methods or instruments for MP analysis. This article also categorized instrumental analysis in MP studies as destructive and non-destructive and highlighted the advantages and disadvantages of methods and instruments such as visual inspection, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy (RS), and Scanning Electron Microscope (SEM). These highlights will provide researchers with a useful guide to help them choose the most appropriate method and instrumentation technique for their MP analytical research. Additionally, the article discusses the combination of two or more of these analytical instruments to improve efficiency. [ABSTRACT FROM AUTHOR]

A new species, Momonides neolandbergi Li & Guo sp. nov. is described in detail, which is the fifth species all over the world in Momonidinae Lundblad, 1941, Momoniidae K. Viets, 1926. The family and subfamily are newly recorded for Chinese fauna. The new species are recorded by camera, optical microscope, and scanning electron microscope. Publication:New species: [ABSTRACT FROM AUTHOR]

The current study demonstrates the effect of Ni-substitution on the structural, dielectric and ferroelectric properties of Ba0.90Sr0.10Ti1-xNixO3 (where x = 0.000, 0.005, 0.015 and 0.025) ceramics, synthesized by solid-state reaction approach. A pure perovskite phase with tetragonal structure has been confirmed by X-ray diffraction (XRD) analysis. Scanning electron microscope (SEM) images revealed change in microstructure. The dielectric behavior of the prepared ceramics was investigated as a function of temperature (30–150°C) at different frequencies. The results indicate that there is an increase in dielectric constant (ϵRT) and low dielectric loss (tanδRT) were obtained at room temperature by substitution of Ni2+ ions in BST ceramics, offering a promising material for capacitor applications at room temperature. Room temperature P-E loops were recorded at different applied electric fields and typical hysteresis loops were obtained. Improvement in the values of Pr and Pmax was observed by substitution of Ni2+ ions. [ABSTRACT FROM AUTHOR]

In this article we have studied, using the Scanning Electron Microscopy SEM LEO 440, the surface electrical properties of MgO (111) irradiated with 30 keV electrons. The study of the evolution of the secondary electronic emission of MgO (111) shows that increases and reaches a value lower than zero. After an injection of 5000 pC, we observe a pseudo mirror, which is due to a very negative surface potential. Finally, we have shown the very high stability of charges within MgO (111) thanks to the use of Atomic Force Microscopy coupled with Scanning Electron Microscope. We can then conclude that MgO (111) is a good trapping insulator. [ABSTRACT FROM AUTHOR]

The seeds of lotus (Nelumbo nucifera Gaertn.) have been used as significant medicinal and nutritional ingredients worldwide. The abundant proteins and polysaccharides in lotus seeds make them susceptible to contamination by aflatoxin (AF), a fungal toxic metabolite. This study was conducted to investigate the susceptibility of lotus seeds at different stages of ripening to AF contamination, as well as the mechanism of the contamination. Seven groups of lotus receptacles with seeds at different ripening stages (A–G, from immature to mature) were used for the experiment. Spores of Aspergillus flavus, an AF producer, were inoculated on the water-gap area of the seeds in each receptacle. Then, each receptacle was covered with a sterilized bag, and its stalk part was soaked in water containing a life-prolonging agent, after which it was kept at room temperature for 14 days. The AF content of each whole inoculated seed from the A–G groups and that of each seed part (pericarp, cotyledon, and embryo) from the D and E groups were determined using high-performance liquid chromatography. Microtome sections were prepared from the samples and observed under a light microscope and scanning electron microscope. The seeds from the A and D groups had higher AF contents than the seeds from the B, C, E, F, and G groups, indicating that the condition of the water-gap area and the development of the embryo and cotyledon parts of the seeds are associated with AF contamination. [ABSTRACT FROM AUTHOR]

The effect of finishing rolling reduction on microstructures and textures of grain oriented silicon steel was researched by optical microscopy, zeiss ultra 55 Scanning Electron Microscope (SEM) and Electron Backscatter Diffraction (EBSD) technique severally. The results show that the grain size of hot rolled sheets and decarburized strips decreases, while the center grain size of the normalized sheet increases with the increase of the finishing rolling reduction. The pearlite content increases with the increase of the finishing rolling reduction after normalization. Compare with the previous research, the effect of finishing rolling reduction on the grain size of primary recrystal-lization is greater than that of roughing rolling reduction, and large rolling reduction is beneficial to the formation of {110}<001> texture. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the structure, physical properties, and antifungal activity of ZnTe single-layer, ZnTe/Cu/ZnTe (ZCZ), and ZnTe/Ag/ZnTe (ZAZ) multilayer films. The ZAZ multilayer had the greatest antifungal efficacy, with ZCZ and ZnTe following in descending order of effectiveness. We observed that ZCZ had a MIC of 0.30 mol/ML and that ZAZ had a MIC of 20 mol/L. An X-ray diffraction (XRD) test confirmed a cubic crystal structure for all films, indicating that the crystals were mainly arranged along the (111) plane. For ZnTe films, the average size of crystallites was estimated to be roughly 15 nm, while for ZAZ and ZCZ films, it remained relatively constant at around 14.2 nm and 14.1 nm, respectively. We determined the particle size of ZnTe, ZCZ, and ZAZ using a scanning electron microscope (SEM) and ImageJ analysis. The obtained sizes were 98 nm, 200 nm, and 81 nm for ZnTe, ZCZ, and ZAZ, respectively. We used Swanepoel method and the Cauchy equation to determine the refractive index (n), film thickness (d), and refractive index as a function of wavelength. We used the Tauc equation to find that the optical band gaps (E g) of the films were 1.67 eV for ZnTe, 1.5 eV for ZCZ, and 1.55 eV for ZAZ. We analyzed six new frequency bands found through FTIR analysis. These bands showed important information about the chemical structure of the films. [Display omitted] • ZAZ films have superior antifungal activity. • The Ag middle layer boosts ZAZ composite efficacy. • Enhanced understanding of ZnTe multilayer's antifungal properties. [ABSTRACT FROM AUTHOR]

Cell deformation often occurs during sample preparation and imaging with scanning electron microscope (SEM), especially with delicate samples, which influences the accuracy of the results. Here we investigate the influence of several preparation methods on cell deformation, using water content and tissue hardness as indicators to classify "delicate" samples of plant species. The degree of deformation in samples resulting from five preparation methods was measured at the tissue and single-cell levels, revealing that a cryo- and methanol-fixation produced lower degrees of tissue dimension deformation and better preservation of cell shape for delicate samples, while for harder tissues, other preparation methods for a dehydrated specimen are also suitable. Stability and image quality of delicate samples could be improved with the application of a cryo-protectant combined with a lower cryo-stage temperature, e.g. − 30 °C. We show that the sample stability under the beam was improved by combining larger sample size and cryo-stage application. Furthermore, the influence of adaxial and abaxial tissue surfaces, the accelerating voltage, and sputter coating time on sample stability and image quality was evaluated. Our study is valuable for artifact reduction and easy application of SEM. • Deformation in samples resulting from five preparation methods was measured at the tissue and single-cell levels. • A cryo- and methanol-fixation led to a lower degree of deformation and better preservation of the delicate tissue surface. • Stability and image quality of delicate samples could be improved with the application of a cryo-protectant. • Our study is valuable for artifact reduction and easy application of SEM. [ABSTRACT FROM AUTHOR]

Phosphogypsum (PG), bauxite residue (BR), and fly ash (FA) are all by-products of different industries. This study presents the development of alkali-activated concrete (AAC) using industrial by-products like PG, BR, and FA. Therefore, the prime aim of this study is to analyze the mechanical and durability properties of the developed AAC. It is noteworthy to mention that the PG is replaced with FA at 10%, 20%, 30%, and 40% for a constant BR ratio. Subsequently, the results reveal that the optimum mix composition of the AAC is 20% BR, 20% FA and 60% PG (P6), resulting in a maximum compressive strength of 54.74 MPa. Additionally, water absorption, sorptivity tests, and the rapid chloride penetration test (RCPT) have been performed to assess the durability of the AAC, and P6 has exhibited the best resistance to the environment. Moreover, scanning electron microscope (SEM) and X-ray diffraction (XRD) test have been carried out to study the micro-characterization of the AAC. The fundamental parameters of the AAC are calcium alumino silicates hydrate gel (C-A-S-H) gel and sodium alumino silicates hydrate gel (N-A-S-H) gel, which play a crucial role in the development of the strength and durability of the AAC. Further, the leaching characteristics of the AAC show that all heavy metals are well solidified during the gel formation. Synergistically developed AAC can be used in construction applications such as foundations, pavements, and building materials as a substation of conventional cement concrete. [Display omitted] • This study focuses on the development of AAC using industrial by-products. • The research highest strength is achieved at 60% PG, 20% BR, and 20% FA. • SEM and XRD results confirm the formation of C-A-S-H and N-A-S-H gels. • Leaching test ensures its minimal impact on the environment. [ABSTRACT FROM AUTHOR]

Considering the long-term working performance of recycled concrete (RC) members, there is a need to compensate for the performance deficiencies of RC. In this study, the mechanical properties of RC were improved by two different modification methods, and the reinforcement effects of RC modified by Silane Coupling Agent (KH560)/Ethylene vinyl acetate copolymer (EVA) and RC modified by EVA alone were compared and analyzed. The effects of separate modification and co-modification on RC were analyzed through multi-scale methods in terms of macro-mechanical properties, microstructure, chemical composition and molecular mechanism, respectively. The results of macroscopic mechanical experiments showed that the compressive and shear strength of EVA/KH560 synergistic modification is higher than that of EVA alone. Scanning Electron Microscope (SEM) data showed that the surface density of the old and new concrete interfaces was higher under EVA/KH560 co-modification. X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) data showed that more cement gel will be produced under EVA/KH560 synergistic modification. Molecular dynamics (MD) simulations show that EVA single modification can produce hydrogen and ionic bonds at the interface of old and new concrete, while EVA/KH560 synergistic modification not only produces them, but also forms a stable Si-O-Si chemical bond. [Display omitted] • Compared with EVA modification, EVA/KH560 synergistic modification has better effect. • EVA/KH560 produces a large number of reticulated cement gel at the weak interface. • The stable Si KH560 -O KH560 -Si CSH is formed between KH560 and cement. • EVA/KH560 enhance the interfacial adhesion by the stable hydrogen and chemical bonds. [ABSTRACT FROM AUTHOR]