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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]

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]

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]

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]

To increase the performance of the compound casting, the corrosion-wear behaviour of a Zinc Silicate coating on the surface of IS 2062 Grade B Carbon Steel using high velocity oxygen fuel spraying is assessed. The microstructure and mechanical properties of the Zinc Silicate coating, as well as its thickness, were investigated. . Scanning Electron Microscope (SEM), X-ray Diffractometer (XRD), surface roughness, and co-efficient of friction were used to investigate the coating's corrosion behaviour. From the perspectives of powder qualities and process parameters, the relationship between microstructure and mechanical properties of coatings was explored. When compared to uncoated materials, experimental results revealed that the microstructure of the coating was noticeable, and the wear properties are also improved. [ABSTRACT FROM AUTHOR]

The treatment method of natural fiber is one of the factors that influences its properties. There are several reports on sodium hydroxide (NaOH) treatment of many natural fiber. Though there are works on NaOH treatment of the fruits fiber, however, works on Borassus flabellifer Leaf fiber (BFLF) is sparsely reported. Hence no report on the optimum conditions for sodium hydroxide treatment of Borassus Flabellifer Leaf fiber. Therefore, this study aimed at establishing the optimum concentration and time for alkaline treatment on the properties of BFLF. The fiber extraction was carried out using water retting method for 24 h. Experimental design was carried out using Design Expert 12.0 adopting Central composite design in response surface methodology. NaOH concentration of 0–5 wt% and time of 1–12 h were used as the independent variables. The responses were water absorption, elongation (%), modulus of elasticity and tensile strength. The surface morphology of the fiber was studied using scanning electron microscope (SEM) and the functional group changes established using Fourier transform infrared (FTIR) spectroscopy to indicate effect of NaOH treatment (FTIR) spectroscopy to show the functional group changes due to NaOH treatment. The optimum concentration and treatment time was established as 2 wt% NaOH and 4 h, respectively, with corresponding responses of water absorption, tensile strength, modulus of elasticity and elongation (%) were 2.07%, 977.378 MPa, 6971.02 MPa, 5.178%, respectively. Using these optimum treatment conditions of time and NaOH concentration, the responses were validated to be 1.88%, 920.019 MPa, 6943.73 MPa, 4.99 mm having a desirability of 0.963. The SEM revealed rough surfaces and increased porosity for the treated fiber compared to the untreated. The FTIR spectra showed reduction in peaks representing lignin at wavelength of 3321.1 cm−1 to 3306.1 cm−1, which indicated that the NaOH treatment resulted to decrease in lignin in the fiber. The properties of the BFLF obtained at the optimum treatment conditions were within range of other fibers used in composite materials development, hence, BFLF treated at these conditions is suitable for composite development. [ABSTRACT FROM AUTHOR]

Second-life applications for lithium-ion batteries offer industry opportunities to defer recycling costs, enhance economic value, and reduce environmental impacts. However, cells are affected by numerous aging phenomena which can lead to an acceleration in capacity loss. This paper uses postmortem techniques to compare aging phenomenon in 1.1 Ah 18650 graphite/LFP cells, examining the differences between a pristine cell and three cells aged to 40~30% of state of health (SoH). Macroscopic and microscopic techniques are used to identify aging phenomenon occurring in the cell on both positive and negative electrodes. Energy-dispersive X-ray spectroscopy (EDXS) and scanning electron microscopes (SEMs) with back-scattered electron (BSE) detector are used to analyze each electrode. These methods are used to analyze the morphology and the material on each electrode. The results show a stable positive LFP electrode whereas numerous deposits and cracking occurred on the negative electrode. A discussion of the appearance of those aging phenomenon is presented. Impacts for industrial cells in second-life applications are finally discussed. [ABSTRACT FROM AUTHOR]

Background: This study compared the influence of crystallization on marginal gap adaptation by using computer-aided design and manufacturing (CAD-CAM) for producing monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns. Methods: A total of 25 plastic teeth were scanned using a Primescan intra-oral scanner (IOS), and ZLS crowns were ground. For each unit (abutment and crown), the marginal gap was evaluated pre crystallization and post crystallization at four regions of interest through the use of a scanning electron microscope (SEM). To compare the marginal gap between the two groups, a Kolmogorov–Smirnov test performed on the study variables indicated a normal distribution (p > 0.05) followed by paired samples T-tests (α = 0.0005). Results: After crystallization, there were significantly higher circumferential marginal gaps (CMGs) for all four surfaces (distal (p = 0.0005), mesial (p = 0.0005), palatal (p = 0.0005), and buccal (p = 0.0005)). The total mean marginal gap (MMG) revealed a significantly higher result for the post-crystallization group (79.82 ± 7.86 μm) compared to the pre-crystallization group (24.25 ± 5.49 μm). Conclusions: The post-crystallization group showed a significantly higher marginal gap compared to the pre-crystallization group in all parameters, but both groups were in the clinically accepted threshold (<120 microns). In terms of the marginal gap, it is arguable whether to carry out post-crystallization for CELTRA® DUO crowns and achieve better mechanical properties but significantly increase the marginal gap. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the present paper to compare the cleaning treatments of paper samples exposed to artificial aging, toluene and isopropyl alcohol gel in cleaning wax stains. Design/methodology/approach: In total, paper samples were made from wood pulp. They had a deterioration phenomenon represented in the stains of the paraffin wax, so two types of cleaning were used: A traditional method using a toluene solution and another new method using isopropanol gel by a cotton swap in a circular movement until the completion of the cleaning process. Then, all paper samples were treated with toluene and isopropanol to handle the second artificial aging and detect how the samples were affected by artificial aging. For identifying the efficacy of these materials in removing paraffin wax stains, a range of examinations and analyses were used, such as universal serial bus, scanning electron microscope, infrared analysis (IR), pH analysis, color change analysis. Moreover, these results were compared with the standard sample's results. Findings: The results of examinations and analyses proved that the use of toluene affected the paper samples. Their effects were twice as weak, fragile and degraded paper fibers compared to isopropanol gel. Therefore, the isopropanol gel is preferred for paper cleaning to the toluene solution. Originality/value: This paper highlights the efficiency of isopropyl alcohol gel in cleaning wax stains from historical paper supports. [ABSTRACT FROM AUTHOR]

The presented research investigated the pollen morphology of endemic Iraqi Hypericum species. The study revealed phenotypic features of pollen grains in the polar and equatorial views and their quantitative and qualitative characteristics. The results showed that the pollen grains of the genus Hypericum were radially symmetrical and isopolar, and their apertures were simple and tricolporate, except the species H. davisii, distinguished as tetracolprate. Dividing the studied species based on pollen grain sizes comprised two groups. Small pollen grains with an average length of the equatorial view ranged between 10-16 µm in H. lysimachioides and H. vermiculare. Medium-sized pollen grains with an average extent between 17-26 µm emerged in the species, i.e., H. retusum, H. triquetrifolium, H. perforatum, H. lydium, H. tetrapterum, H. asperulium, H. scabrum, and H. davisii. Pollen grains, also divided according to the P/E ratio, had two main groups. The pollen grains were subprolate and spherical, with the exine sculpturing examined by a scanning electron microscope (SEM), and isolated into four groups: 1) microreticulate reticulum, including H. asperulium, H. lydium, and H. vermiculare, 2) perforate, i.e., H. retusum, H. scabrum, H. tetrapterum, and H. triquetrifolium, 3) psilate with H. perforatum and H. davisii, 4) and reticulate exine sculpturing in H. lysimachioides, all isolated from the rest of the species. SEM images showed the thickness of exine ranged from 0.5 to 2 µm. The topical study also added H. davisii as a new species with no previous records in Iraq. This pollen study added valuable data for taxonomy and suggested that it should proceed with its first-time registration in Iraq. The pertinent research could provide a taxonomical key for Hypericum species in Iraq. [ABSTRACT FROM AUTHOR]

Pollen morphology of 26 taxa of Clerodendrum, as well as one species of Volkameria from China, was investigated through a scanning electron microscope (SEM). Pollen grains of Clerodendrum are monads, radiosymmetric and tricolpate, with medium or large size. The equatorial view of the pollen grains is spheroidal or subprolate and the polar view is (sub) circular or rounded triangular. The colpus membrane of the investigated taxa is sunken (rarely even). Five varying pollen types are delimited on the basis of exine sculpturing: (1) spine-tectum perforatum; (2) spine-tectum imperforatum; (3) microspine- tectum perforatum; (4) microspine-tectum imperforatum; and (5) obtuser spine. The results indicate that Clerodendrum is closely related to several genera in Lamiaceae, including Aegiphila, Amasonia, Kalaharia, Tetraclea, Volkameria, Oxera, Faradaya, and Hosea, as supported by previous phylogenic studies. Additionally, the conventional infrageneric classification of Clerodendrum based on inflorescence and leaf characters is not supported by the results. However, the palynological data can be used to identify some closely related species with similar external characteristics. In conclusion, the investigation of pollen morphology not only contributes novel data from palynology for Clerodendrum but also provides a basis for future comprehensive classification of this genus. [ABSTRACT FROM AUTHOR]

Abundant research on geopolymer concrete in the last two decades has provided worldwide acceptability in conventional structural applications. The high-impact applications of geopolymers are mostly limited because they are quasi-brittle in nature and show moderate crack resistance; hence, they require suitable reinforcing materials such as fibers. This paper reports a study to assess the strength and durability properties of fly ash-based geopolymer concrete (FA-GPC) prepared with novel C-glass fibers. The binder mix was comprised of Fly Ash (FA), Lime (L), Silica Fume (SF) and was activated by sodium hydroxide (12 M) and sodium silicate solution, followed by curing under ambient conditions. Glass fibers were utilized in varying proportions (0.125, 0.25, 0.375, 0.5, 0.625, and 0.75%), by weight of the binder mix. It was found that the incorporation of 0.5% glass fiber significantly increased the compressive strength, split tensile strength, and flexural strength properties. From the durability perspective, the samples exhibited good resistance against seawater, MgSO4 solution, and H2SO4 when compared with the control mix. Further, the Scanning Electron Microscope (SEM) analysis was employed to explore the nature of the geopolymer–fiber matrix. It was revealed that excellent interfacial bonding existed between fiber and the geopolymer matrix. The results indicate that addition of C-glass fibers significantly improves the overall mechanical performance of FA-GPC. The research presented here establishes the advantages of using C-glass fibers-based geopolymer concrete, thus encouraging its broader utilization. [ABSTRACT FROM AUTHOR]

The main aim of this work is to comparatively reveal the effect of fibre type, length and content on compressive strength and microstructure of structural geopolymer concrete (GPC) produced under constant mixture and curing parameters in order to address the significant gap in present literature. Firstly, GPCs with different NaOH concentrations (i.e., 6, 9, 12 and 15 M) and activator solution/binder (a/b) ratios (i.e., 0.45 and 0.55) were produced in ambient curing condition, and optimum production parameters were determined based on the preliminary evaluations. Then, glass and polypropylene fibres in 6‐mm length (GS6 and PP6) and polyamide and polypropylene fibres in 12‐mm length (PY12 and PP12) were included in GPCs at ratio of 0.4%, 0.8% and 1.2% (by volume). Compressive strength, apparent porosity, bulk density, ultrasonic pulse velocity (UPV), X‐ray diffraction (XRD) and scanning electron microscope (SEM) analysis of GPC samples were carried out comparatively. The inclusion of GS6 fibre enhanced the compressive strength thanks to fibre surface being covered by geopolymer gel and the strong adhesion between GS fibre and geopolymer matrix. SEM images of fibre reinforced GPC (FRGPC) also confirmed the experimental findings, which were attributed to improvement in compressive strength. Regardless of the fibre type, the maximum compressive value strength was obtained from GPC specimens with 0.4% fibre and then decreased. Higher fibre inclusions led to poor compaction, workability issues and inhomogeneous fibre dispersions. A very good relation (R2 = 0.98) was acquired between UPV and compressive strength values of GPC/FRGPC samples. [ABSTRACT FROM AUTHOR]

In most natural habitats, microbes are not discovered in the planktonic phase but in multispecies biofilm communities. Bacteria in diverse microbial biofilm may interact or conflict relying on the varieties and features of solid surfaces. Hence, mono-species biofilm formed some potentially Gram-negative pathogenic species, including Escherichia coli, Salmonella enterica, and Pseudomonas aeruginosa, on two different materials: stainless steel (SS) and polypropylene (PP) were investigated. The developed biofilm was comprehensively studied using different approaches. Results displayed that the biofilm developed upon SS was more intensive than on PP. Statistically, a compelling correlation with significance was recorded between the biofilm age and increasing bacterial biofilm populations formed upon PP and SS materials. Likewise, the excellent levels of produced adenosine triphosphate (ATP) from the biofilm formed upon both PP and SS were reached after 80 days. The scanning electron microscope (SEM) micrographs exhibited the surface structure of biofilm for E. coli, S. enterica, and P. aeruginosa developed upon two materials (PP and SS). The results show that, the formed biofilm cells for all tested bacterial strains grown upon PP material were more minor than SS. In conclusion, the existing investigation delivers better knowledge about the approaches that could be applied to investigate biofilm formation on various surface materials. Likewise, biopolymers such as extracellular polymeric substances (EPS) play a critical role in establishing clusters and microcolonies. [ABSTRACT FROM AUTHOR]

Meloetyphlus Waterhouse is a monotypic genus of Meloidae ascribed to the tribe Tetraonycini, subfamily Meloinae. As for most blister beetles, its first-instar larvae (or triungulins) are parasites of bees, but M. fuscatus Waterhouse is the only species known to parasitize members of the tribe Euglossini (Hymenoptera: Apidae: Apinae). Despite being widely distributed in Central and South America, its presence in Colombia has never been confirmed. In this article, we document the occurrence of this genus in Colombia providing the first certain record for this country. In addition, some aspects of its parasitization of Eulaema nigrita Lepeletier are reported and illustrated with macrophotographs and a video. By the means of drawings and SEM micrographs, we provide the most detailed description of the first-instar larva of M. fuscatus to date and a comparison with the triungulin of the closely related Tetraonyx fulvus (LeConte). Finally, we investigated the phylogenetic position of Meloetyphlus using molecular data, to support its attribution to the tribe Tetraonycini. [ABSTRACT FROM AUTHOR]

Sulphur is rapidly being recognized as the fourth key nutrient for plants after nitrogen, phosphorus, and potassium. It functions in several critical metabolic and physiological processes, such as Chlorophyll synthesis, Protein synthesis, Activation of enzymes, Stress tolerance and Seed production. In this background, an attempt was made to synthesize nano sulphur fertilizers for slow release using the reverse microemulsion (water-in-oil microemulsion) technique. Cyclohexane was used as oil phase. Tween-80 and ethanol were used as surfactant and co-surfactant, respectively. Hydrochloric acid and sodium polysulfide solution acted as an aqueous phase. This technique resulted in the successful synthesis of nano sulphur fertilizer. The sulphur nano fertilizer was characterized using X-ray diffraction (XRD), Fourier-Transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM) and Thermogravimetric analysis (TGA). The XRD pattern revealed the orthorhombic nature of nano sulphur and the lattice face-centred. The FTIR spectra at 1406 cm-1 confirmed the sulphur vibrations. The microemulsion method yielded stable, uniform, spherical nano sulphur particles with dimensions ranging from 25 to 47 nm. The thermal disintegration between 117°C to 122°C in TGA graph was attributed to the sublimation of sulphur in orthorhombic crystalline form, indicating the successful synthesis of nano sulphur. A laboratory study on nano sulphur fertilizer and conventional sulphur fertilizer was studied with a Percolator reaction system to evaluate the slow release of sulphur from both fertilizers at ambient temperature. Percolation reactor experiment indicated that sulphate release from nano sulphur was longer for 42 days than gypsum amended soil which exhausted within 35 days. Hence, synthesized nano sulphur fertilizer maximizes nutrient retention, eliminates environmental nutrient loses and decreases fertilizer requirements. [ABSTRACT FROM AUTHOR]

Self-cementing fly ash, containing calcium oxide (CaO) of about 20%, has successfully become a sole binder material in concrete through hydration. A very low water-to-fly ash ratio, e.g., below 0.20, is the main key to achieving the high compressive strength of concrete. This study explores the strength evolution, long-term compressive strength, and mechanical properties of concrete that utilize self-cementing fly ash as a sole binder material. Remarkably, the long-term compressive strength continues to develop over a year, reaching nearly 50 MPa at 365 days, a 34% increase from the 28-day strength. While the other mechanical properties are slightly lower than predictions from empirical formulas for Portland cement concrete, promising results are observed. Scanning Electron Microscope (SEM) images highlight surface-restricted hydration products in self-cementing fly ash, rather than full dissolution of fly ash particles. [ABSTRACT FROM AUTHOR]

This research reports erosion wear characteristics of polyester matrix composite reinforced with short fibres of sugar cane. Erosion tests were conducted using silica sand particles of size (200–500 µm) using a locally designed air jet-type erosion test rig. The sugarcane fibre-reinforced polyester composites (5% wt.) with different fibre lengths (3, 12, 48 mm) were impacted by sand particles at a fixed velocity of 60 m/s, impact angles (30°, 60°, 90°) and erodent weight of (2500,7500) gm. ANOVA approach was used to determine the most significant parameter and their combinations that minimize the erosion rate. Scanning Electron Microscope (SEM) observations were conducted to investigate the erosion mechanisms. Results indicated that the erosion rate is greatly influenced by fibre length as well as the erodent weight. Moreover, at an erodent weight of 2500gm, the behaviour of the material turns from brittle into ductile. At an erodent weight of 7500gm, the erosion rate is inversely proportional to the fibre length. [ABSTRACT FROM AUTHOR]

In the routine maintenance of each main pump in the oil transmission station plant, abnormal erosion wear was found at the flushing port of the mechanical seal of Sulzer pump casing. For the sake of stable and safe unit operation, this study explored the mechanism and process of erosion formation in the pump casing at the microscopic level using SEM (scanning electron microscope) and EDS (energy dispersive spectrometer) techniques. And ANSYS Fluent was used to numerically simulate the unconventional turbulent flow in the special location of Sulzer pump to obtain its flow field characteristics. The trajectory tracking of solid phase particles based on Finnie erosion model was also carried out to obtain the influence law of different particle sizes on the wear degree of each area of the pump casing, and to point out the influence of the motion behavior of particles at the flushing port position on the erosion. The results show that there is unconventional turbulence in the flushing port of the Sulzer pump mechanical seal, and the solid particles are affected by turbulent diffusion and fluid adhesion, and some particles deviate from the velocity direction and continuously impact the surface of the pump casing, which is the direct cause of the erosion wear here. By optimizing the location of the flushing port, severe erosion wear at the flushing port can be avoided. This study can provide guidance and recommendations for the production, operational stability and wear protection of Sulzer pumps. [ABSTRACT FROM AUTHOR]

Durability testing of low temperature solid oxide cells is challenging as degradation phenomena related to microstructural changes like nickel‐agglomeration are slow. In the present study, a nickel/gadolinia doped ceria (GDC) fuel electrode with a porous GDC‐interlayer towards the zirconia electrolyte was investigated. The electrode, designed for operating temperatures of 600°C, was tested at an elevated temperature of 900°C for up to 1100 h to accelerate aging. Contrary to every expectation, the electrodes showed continuous improvement in electrochemical performance. Impedance spectroscopy, the distribution of relaxation times analysis, scanning electron microscope and transmission electron microscope were applied to correlate electrochemical and microstructural changes. Structural analysis showed a significant Ni agglomeration accompanied by a decrease in triple phase boundary density. Furthermore, a minor particle growth in the GDC‐phase decreased the volume‐specific double phase boundary GDC/pore. Considering these microstructural changes, the decrease in active reaction sites should have increased the polarization resistance, but a decrease of about 32% was observed. The discrepancy between polarization resistance improvement and microstructural degradation might be attributed to an activation of the GDC‐surfaces in the electrode and the porous GDC‐interlayer. [ABSTRACT FROM AUTHOR]

The Schiff base compound, benzyl hydrogen-4-(dimethylamino) benzylidene hydroxycarbon hydrazodithiate (BHDBHH), was investigated under continuous wave laser beam irradiation (30 mW), and its chemical properties were analyzed. The material's chemical properties were found to be affected during laser processing. We examined the chemical properties of the Schiff base using a Scanning Electron Microscope (SEM) and energy-dispersive Xray (EDX) Spectroscopy. By varying the exposure time, we discovered that longer exposure times resulted in a darker colouration of the compound, even at a low power of 30 mW. This finding led us to conclude that the compound is highly sensitive to laser exposure and can be easily diffused with a more powerful laser. The EDX test revealed a significant reduction in the sulfur element, with more than 50% of it being burned during the exposure. [ABSTRACT FROM AUTHOR]

This paper presents a method for capturing Scanning Electron Microscope (SEM) photographs of small specimens, including nematodes, arthropods, small insects, and other meiofauna. Our method is tailored to handle nematode specimens mounted on permanent slides, an area with relatively limited documentation. Besides, the process of transferring such delicate specimens from one solution to another has historically posed numerous challenges. To address this issue, we introduce a low-cost and easy-made container designed specifically to facilitate the aforementioned procedure, with a particular focus on SEM photography. The newly introduced container offers a practical solution that enhances the efficiency and effectiveness of specimen handling, ultimately enabling high-quality SEM imaging. This method holds significant promise for researchers working in the field of micro-scopic organism analysis, providing a valuable tool for their investigations with minimum cost. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium species) was used as textile fibre already in the early Indus culture, and since then it has been cultivated in Tropical and Subtropical regions around the whole planet. The species G. hirsutum is nowadays the dominant cotton crop with more than 90% of the world market, while G. barbadense, G. herbaceum and G. arboreum combined, the other cultivated species of Gossypium genus total a minor part of world's cotton production. Even in places where cotton was not cultivated, it could be an important trade item and income source for local textile centres, with the imported raw cotton lint being spun, woven and for some part exported from such sites around the globe. This all occurred far away from Finland, until changes brought by the development of long-distance trade and the Industrial Revolution. Based on archaeological finds, cotton as a textile material reached Finland relatively late, in the early Middle Ages. The article focuses on the problematic nature of identifying these cotton finds: whereas modern cotton fibres are easy to identify, the archaeological finds can at first sight be confused with bast or un-degummed silk fibres. This issue will be approached through reviewing recent Finnish cotton finds in heritage textiles. Additionally, the article examines whether the four cultivated cotton species could be differentiated using both classical and newly developed fibre identification methods, such as optical microscopy methods, a Scanning Electron Microscope (SEM), Fourier-transform infrared spectroscopy (FTIR) or Wide-Angle X-ray Scattering (WAXS). [ABSTRACT FROM AUTHOR]

A novel Bi-Mg-O composite nano-catalyst was prepared by using Bi(NO3)3 and nano-MgO. Prepared catalyst was characterized using x-ray diffraction (XRD) analysis, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) technique which confirms its nano-crystalline nature and composition. The synthesized novel catalyst Bi-Mg-O was found to be competent catalyst for the synthesis of spirooxindole derivatives by multicomponent reaction of isatin, dimedone, malononitrile and 4H-pyran derivatives by reaction of dimedone, aryl aldehydes and malononitrile using ethanol as solvent at room temperature. The nanocatalyst proved to be recyclable as it is recycled and recovered for three runs without notable loss in catalytic activity. All synthesized derivatives were obtained in exemplary yields. Novel recyclable nanocatalyst, good yields of products, and benign reaction conditions are the noteworthy aspects of the present protocol. [ABSTRACT FROM AUTHOR]

Chloride ions play an important role in the corrosion of bronze through their active reactivity to copper alloys. The corrosion behavior of bronze alloys in NaCl solution was investigated by using X-ray diffraction (XRD), a scanning electron microscope (SEM), and electrochemical tests, with a special emphasis on the corrosion resistance of the α and δ phases in Cu-20 wt%Sn bronze alloys. The experimental results show that the corrosion current density of Cu-20 wt%Sn bronze alloys increases from 1.1 × 10−7 A/cm2 to 2.7 × 10−6 A/cm2 with the increase in the chloride ion concentration from 10−3 mol/L to 1 mol/L. After a soaking duration of 30 days, the matrix corrosion depth reaches 50 μm. The α phase of the alloys is easily corroded in NaCl solution, while the δ phase with high Sn content has strong corrosion resistance. This study provides relevant data for the analysis and protection of ancient bronze alloys. [ABSTRACT FROM AUTHOR]

Objectives. The purpose of the present study was to evaluate by scanning electron microscope (SEM) and energy dispersive spectrophotometry (EDS), the degree of bone mineralization of the tissues on the surface of faliure dental implants with immediate or late loading. Materials and method. In the study, 8 dental explants from 8 clinically healthy, non-smoking patients were taken. All implants were inserted by the same dental surgeon, 4 of them were immediate loaded and 4 were late prosthetically loaded by the same dentist. The ablation of the implants was performed as atraumatically as possible and they were collected in sterile containers and sent to the BIOMAT Research Center, where they were subjected to SEM and EDS analyses. The ratios between the chemical elements calcium and nitrogen (Ca/N), phosphorus and nitrogen (P/N), respectively calcium and phosphorus (Ca/P) were calculated for each of the 8 samples and were statistically analyzed. Results. If we compare the degree of coverage of the implants with bone tissue in different phases of mineralization, we find that the bone structures occupy a larger surface area of the implants in the cases with immediate loading compared to the cases with late loading. Thus, out of 4 immediately loaded implants, 2 were completely covered, one showed very little exposed areas, and the fourth showed alternating covered and uncovered areas. Regarding the late loaded implants, three showed alternation between covered and uncovered areas and only one was completely covered with bone. Conclusions. The degree of coverage of the explants with bone tissue was better represented for the immediate loading cases. The degree of mineralization of the bone tissue covering the explants was higher for cases with immediate loading.To confirm the obtained results, it is necessary to expand the study on larger batches of samples. [ABSTRACT FROM AUTHOR]

Objectives. The aim of the study was to evaluate comparatively by scanning electron microscope (SEM) and energy dispersive spectrophotometry (EDS) the physical and chemical homogeneity of some luting materials used for cementation of three types of posts. Materials and method. We selected 12 irretrievable monoradicular teeth extracted in our dental offices. After extraction, all teeth were prepared for cementation with 4 different cements (NANOCORE DUAL, CEMBEST, PANAVIA SA and CEMENT-ONE) of three types of posts: prefabricated titanium post, FibreKleer 4x fiberglass post (Pentron) and post cast from NiCrMo alloy. Afterwards, the samples were embedded in resin and prepared metallographically for examination with the Phenom ProX scanning electron microscope equipped with an energy dispersive spectrophotometer with X Rays. Results. SEM studies provide valuable ultrastructural information regarding the degree of filling with luting materials. The four studied cements do not present an inhomogeneous composition in the EDS analysis, not having significantly increased values between the 2 analyzed points for each of the 12 samples taken in the study. Conclusions. Among the four luting materials studied comparatively, PANAVIA SA seems to best fill the existing spaces between posts and the limits of dental preparations, being closely followed by CEMENT-One and CEMBEST. In last place is NANOCORE DUAL, which presents discontinuities in the mass of material and at the border with the preparations. [ABSTRACT FROM AUTHOR]

AlMg0.5Si (AA6063) as a base matrix composite with different weight percentages of Titanium (Ti) has been synthesized by the stir casting method. Objective of this research is to investigate the effect of Ti addition on AA6063 to produce aluminium matrix composites (AMCs). AA6063, AA6063/4%-Ti, AA6063/8%-Ti, and AA6063/12%-Ti are different volume fractions. The Scanning electron microscope (SEM) analysis is used to examine the modified grain refinement and worn surface on fabricated AMCs. The evenly distributed structure was attained on the processed AA6063/Ti combinations. The mechanical properties of processed composites were investigated with the following experimental tests such as tensile strength, impact strength, micro hardness, compressive, and flexural strength. The entire mechanical properties of fabricated AMCs were enhanced with increasing Ti reinforcement particles. The CNC drilling of AA6063/Ti composites was machined by spindle speed, feed and depth of cut. The gray relational analysis (GRA) was used to carry out the optimal machining parameters with their responses such as material removal rate and surface roughness. From the analysis of ANOVA, spindle speed parameter achieved most influencing parameters. [ABSTRACT FROM AUTHOR]

The uncharacteristically extreme outbreak of particulate matter took place over the Balkan region from 27 to 30 March 2020. Observations at air quality stations in Croatia recorded hourly PM10 concentrations up to 412 μgm−3. The meteorological analysis shows that the increase in PM10 concentrations was primarily due to the advection of dust from the deserts east of the Caspian Sea. The anticyclone north of Croatia and the cyclone over Anatolia formed a strong pressure gradient driving transport from the east. Both back trajectories and satellite products pointed to the dry Aral Sea as the main source of dust. A dust plume influenced the PM10 increase observed in Croatia, starting at the easternmost air quality stations. The modeling study shows that the vertical extent of the dust plume was up to ∼2 km. However, the chemical and morphological (scanning electron microscope analysis) composition of PM10 at the sites in the northeastern Adriatic Sea showed mainly the presence of Saharan dust. Prior to the advection of the Asian dust, the transport of Saharan dust, driven by Sharav cyclone, was observed in the PM10 values at several stations in the Adriatic Sea and on the Croatian mainland on 26 March 2020. Modeling results showed that the Saharan dust transport occurred at altitudes below ∼8 km. The mixing of the Asian and Saharan dust plumes over the Balkans was favored by the subsidence due to anticyclonic high‐pressure conditions and is the most likely explanation for the observed PM chemical and morphological results. Plain Language Summary: The event of extreme air pollution in Croatia occurred at the end of March 2020. Exceptionally high aerosol concentrations were observed at several air quality stations. The outbreak was studied using a numerical chemical transport model. Chemical analysis was also performed for the aerosol sample and the sample was viewed with an electronic microscope. The analysis revealed that the composition of the aerosol was due to desert dust transported by air masses from the deserts east of the Caspian Sea and the Sahara Desert. Key Points: The extraordinary dust episode over the Balkan region was simulated with the WRF‐Chem modelThe dried Aral Sea was identified as the main source, but the dust plume from the Sahara was also presentChemical and morphological analysis of the PM10 sample shows that the dust originated from the Sahara Desert [ABSTRACT FROM AUTHOR]

Metalloenzymes play an important role in the regulation of many biological functions. An effective way to prevent deficiencies of essential minerals in human diets is the biofortification of plant materials. The process of enriching crop sprouts under hydroponic conditions is the easiest and cheapest to conduct and control. In this study, the sprouts of the wheat (Triticum aestivum L.) varieties Arkadia and Tonacja underwent biofortification with Fe, Zn, Mg, and Cr solutions in hydroponic media at four concentrations (0, 50, 100, and 200 µg g−1) over four and seven days. Moreover, this study is the first to combine sprout biofortification with UV-C (λ = 254 nm) radiation treatment for seed surface sterilization. The results showed that UV-C radiation was effective in suppressing seed germination contamination by microorganisms. The seed germination energy was slightly affected by UV-C radiation but remained at a high level (79–95%). The influence of this non-chemical sterilization process on seeds was tested in an innovative manner using a scanning electron microscope (SEM) and EXAKT thin-section cutting. The applied sterilization process reduced neither the growth and development of sprouts nor nutrient bioassimilation. In general, wheat sprouts easily accumulate Fe, Zn, Mg, and Cr during the applied growth period. A very strong correlation between the ion concentration in the media and microelement assimilation in the plant tissues (R2 > 0.9) was detected. The results of the quantitative ion assays performed with atomic absorption spectrometry (AAS) using the flame atomization method were correlated with the morphological evaluation of sprouts in order to determine the optimum concentration of individual elements in the hydroponic solution. The best conditions were indicated for 7-day cultivation in 100 µg g−1 of solutions with Fe (218% and 322% better nutrient accumulation in comparison to the control condition) and Zn (19 and 29 times richer in zinc concentration compared to the sprouts without supplementation). The maximum plant product biofortification with magnesium did not exceed 40% in intensity compared to the control sample. The best-developed sprouts were grown in the solution with 50 µg g−1 of Cr. In contrast, the concentration of 200 µg g−1 was clearly toxic to the wheat sprouts. [ABSTRACT FROM AUTHOR]

The underlying objective of this study was to synthesize [gum ghatti-cl-poly(N-isopropyl acrylamide-co-acrylic acid)/CoFe2O4] nanocomposite hydrogels using free radical polymerization method. Gum ghatti (Gg) as a biopolymer, N-isopropyl acrylamide (NIPA) and acrylic acid (AA) as a monomer, ammonium persulphate (APS) and N,N-methylene bis-acrylamide (MBA) were used as initiator and cross-linking agents, respectively. The characterization of as prepared gels was performed by scanning electron microscope and X-ray diffraction techniques. The present study focuses on the swelling behaviour and rheological investigations of the hydrogels. Different tests were performed on nanocomposite prepared particle gels to investigate the effect of CoFe2O4 nanoparticle content (0–60 mg) concentration on network structure, swelling, and mechanical behaviour of the gels. The Gg‑cl‑P(NIPA-co-AA)/CoFe2O4 with 30 mg CoFe2O4 exhibited a superior swelling ratio. Loading of 30 mg CoFe2O4 into Gg‑cl‑P(NIPA-co-AA matrix resulted in capable mechanical stability. All the experiments illustrate that the Gg‑cl‑P(NIPA-co-AA)/CoFe2O4 nanocomposite hydrogel is the best candidate for its use as flocculants and absorbents. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to investigate surface treatments and fiber types on adhesion properties polylactic acid (PLA) three-dimensional (3D) parts printed on woven fabrics. Design/methodology/approach: The cotton, flax and jute fabrics were exposed to alkali, hydrogen peroxide, stearic acid and ionic liquid treatments to modify surface characteristics before PLA 3D printing. The modification efficiency was assessed with Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) analyses. Then, fused deposition modeling (FDM) printer and PLA filament were used for 3D printing onto the untreated and treated fabrics. The adhesion strength between the fabrics and PLA 3D parts were tested according to DIN 53530 via universal tensile tester. Findings: The fabric structure is effective on adhesion force and greater values were observed for plain weave fabrics. Maximum separation forces were obtained for alkali pretreated fabrics among jute and cotton. Hydrogen peroxide treatment also increased adhesion forces for jute and cotton fabrics while decreasing for flax fabrics. Stearic acid and ionic liquid treatments reduced adhesion forces compared to untreated fabrics. Treatments are effective to alter adhesion via changing surface chemistry, surface morphology and fabric physical properties but display different effects related to fabric material. Originality/value: This study provides experimental information about effects of different fiber types and surface treatments on adhesion strength of PLA 3D parts. There is limited research about comprehensive observation on 3D printing on cellulosic-woven fabrics. [ABSTRACT FROM AUTHOR]

In order to enhance storage capacity and prevent electrical short circuits in electrochemical storage devices, it is essential and challenging to design and build Lithium ion batteries with flexible solid polymer electrolyte possessing strong ionic conductivity. This study details the use of solution-cast technique to create nano composite doped lithium solid polymer electrolytes (n-LSPEs), from polymer complex of poly (vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), polyethylene oxide (PEO), and Lithium trifluoromethanesulfonate (LiCF3SO3), with nano ZrO2 (n-ZrO2). Electrochemical impedance spectroscopy (EIS) was utilised to describe the ionic conductivity values in presence of alternating fields. The ionic conductivity of n-LSPEs are enhanced nearly four times (1.54 × 10─1 mS/cm to 5.996 × 10─1 mS/cm) due to addition of n-ZrO2. By incorporating chronoamperometry (CA) and cyclic voltammetry (CV), we were able to analyse the transference number, ionic strength, and the accumulation of charge carriers in optimized n-LSPE membrane. Scanning electron microscope (SEM) images of n-LSPE membranes reveal a structure that is consistent with interconnecting pores between the polymer complex and the nano filler. The stable monoclinic phase of n-ZrO2 interaction with polymer segmental motion was confirmed by X-ray diffraction (XRD). By examining Fourier transform infrared spectroscopy (FTIR), we performed a quick analysis of the complexation of functional group investigations, bond length and force constant calculations, interaction of functional groups of n-LSPE films. Our FESD's discharge characteristics were investigated at 4.8 mA average discharge current for 25 hours, as indicated by a 0.04C rating. [ABSTRACT FROM AUTHOR]

Purpose. This in vitro study compared the vertical marginal discrepancy (MD) and absolute marginal discrepancy (AMD) between the zirconia substructure and titanium (Ti)-base abutment before and after cementation. Material and methods. An intraoral scanner (CEREC Omnicam scanner; Dentsply Sirona) was used to scan the dental model of missing tooth 36 and obtain a three-dimensional virtual model. It was designed and milled for 25 zirconia superstructures (inCoris ZI meso F2 L, Dentsply Sirona). The samples were cemented to Ti bases. The MD and AMD were measured for each sample by using a scanning electron microscope (SEM) before and after cementation. Results. The overall mean values of MD measurements before and after cementation were 14.12 μm and 20.28 μm, respectively. The overall mean values of AMD measurements prior to and after substructure cementation on the Ti base were 54.85 μm and 116.0 μm, respectively. ANOVA revealed significant differences in MD (p = 0.001) and AMD (p < 0.001) before and after cementation. Conclusions. Significant differences were observed in MD and AMD values before and after cementation. The MD and AMD values were significantly lower before cementation than after cementation. The mean MD and AMD values were clinically acceptable. [ABSTRACT FROM AUTHOR]

This work focuses on the effect of the incorporation of marine shell waste in different mass substitution rates in geopolymer mortars as an efficient solution to overcome the problems related to this waste. In this paper, Lebanese metakaolin was used as the primary clay source of aluminosilicate for the geopolymer mortars. Then, a mass substitution of metakaolin with shell waste was drawn in terms of structure, synthesis mechanism, and parameters delimiting their performance. The chemical properties of all constituents were investigated using X-ray diffraction analysis and X-ray Fluorescence. Also, the microstructure analysis was observed by implementing a scanning electron microscope (SEM). The compressive strength and elasticity modulus were measured as two fundamental mechanical properties of geopolymer samples by highlighting the impact of curing conditions (non-heated and heated) after passing 1, 3, 7, 28, 90, 120, 180, and 360 days and the various substitution rates (0–20%). The results showed that the curing conditions and the various substitution rates of metakaolin with marine shells affected the microstructure and mechanical properties. Adding shell waste reduced the compressive strength for both non-heated and heated samples and slightly increased the elasticity modulus up to 10% for non-heated and for heated curing conditions. While the final compressive strengths of non-heated samples are greater than heated ones, the rate of achieving a specific compressive strength is more rapid for heated samples. An environmental and economic analysis showed that assuming an equal transportation cost, replacing metakaolin with an average amount of 10% seashell waste reduces the energy usage by 7% and the price by 2% to produce 1 ton of geopolymer and preserves the non-renewable sources of Kaolin clay and solves the problems related to seashell waste deposits. [ABSTRACT FROM AUTHOR]

This paper presents a study on the effects of graphene nanoplatelets (GNPs) on the mechanical behavior of 3D-printed burnt clay, the most sustainable and green construction material, under constant printing parameters. Mixes with different nanofilament contents—0.1%, 0.2%, and 0.3% by clay weight—were printed and tested under compression and bending loadings. The results obtained on the printed samples were compared with those fabricated using the molding method. The samples' microstructures were then analyzed using a scanning electron microscope (SEM). Energy dispersive X-ray (EDX) analysis was employed to obtain the elemental distributions. The testing results were then statistically analyzed using a t-statistical method to investigate the impact of using GNPs on the properties of 3D-printed clay. Strength test results showed that mixes containing a low GNP content, i.e., 0.1 wt.%, attained higher compressive and flexural strengths than those containing higher contents, i.e., 0.2 and 0.3wt.%. The results additionally highlighted that the efficiency of GNPs was better observed in the printed samples rather than the molded ones, indicating that the printing process contributed to a better and more uniform dispersion of GNPs in the clay matrix. The t-statistical analysis confirmed that a significant improvement in compressive strength could be obtained using a GNP content of 0.1 wt.%, regardless of the fabrication method. On the other hand, significant flexural strength improvements were observed in the printed samples at all GNP dosages. Micrographs of GNP-modified clay supported the strength results obtained in this study. In summary, this research work signified the importance of using nanofilaments in 3D printing applications in order to achieve the desired elements' mechanical properties. [ABSTRACT FROM AUTHOR]

This paper investigated carbon steel corrosion in an enclosed environment, where one set of steel was immersed in 3.5 wt.% NaCl solution and another exposed to humid (condensation) conditions. The study employed electrochemical noise and electrochemical impedance spectroscopy techniques to monitor real time corrosion behaviour. The samples were evaluated with surface characterisation techniques including optical light microscope, scanning electron microscope with energy dispersive X-ray spectroscopy, and Raman spectroscopy. The results showed that carbon steel immersed in the liquid phase at a constant temperature exhibited the highest weight loss. However, the carbon steel exposed to water condensation (gas phase) at 80 °C manifested extensive localised corrosion. EN results agreed with the microscopy findings. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate the feasibility of using the originally developed Laser Induced Breakdown Spectroscopy (LIBS) laboratory setup for the qualitative analysis of human tooth tissues and tooth restorations. Plasma was induced by the infrared TEA (Transversally Excited Atmospheric) CO2 laser in the air under atmospheric pressure. Optical emission spectra with sharp and well-resolved spectral lines and a negligibly low background were obtained. The results of the qualitative analysis showed the presence of various elements in the tooth tissues (P, Ca, and Mg), as well as trace elements within restorations such as Zn, Sn, Cu, Ag, and Hg. The estimated temperatures of plasma for composite, dentin, and amalgam were 21,000 K, 16,200 K, and 13,300 K respectively. The electron density deduced from the Stark-broadening line profiles varies from 8.5 × 1017 cm− 3 for amalgam, 2 × 1018 cm− 3 for composite, and 1.9 × 1018 cm− 3 for dentin. The surface of the tooth tissue was imaged with a scanning electron microscope (SEM), showing that dentin contains pores, cavities and bubbles. The results indicated that the alternative and cost-effective LIBS system can be used as a useful tool for further research on laser-induced plasma in dentistry. These insights are useful in the field of laser dentistry, where lasers are commonly utilized to treat teeth. [ABSTRACT FROM AUTHOR]

Since pollen characters can be used to help distinguish species, our aim was to determine if palynological information has taxonomic significance for Gagea species from Xinjiang, China. Gagea is widely distributed in north temperate and the subtropical zones. The genus has limited taxonomic characteristics and large morphological variation, which results in difficulty of species classification. Pollen morphology of 16 species of this genus was examined comprehensively via light microscope (LM) and scanning electron microscope (SEM). One qualitative and nine quantitative traits of the pollen grains were surveyed, followed by hierarchical cluster analysis (HCA). The pollen grains were bilaterally symmetrical heteropolar monads with a mono-sulcus and they were oblate or peroblate (Polar diameter (P) / Equatorial diameter (E) = 0.36-0.73) in shape and medium to large (P = 17.17-34.64 µm, E = 27.63-81.65 µm) in size. Three types of exine ornamentation were observed: perforate, microreticulate and reticulate cristatum. The HCA divided the 16 species into two groups. This research provides new data on pollen morphology for Gagea (the pollen morphology of eight species was reported for the first time). Pollen morphology also can be used to identify species with similar external morphology, such as G. nigra and G. filiformis. Furthermore, the study of pollen morphology not only provides new data for palynology research on Gagea, but also provides a basis for future classification of this genus. [ABSTRACT FROM AUTHOR]

In this paper, low‐strength polyvinyl alcohol (L‐PVA) fibers, high‐strength polyvinyl alcohol (H‐PVA) fibers, and polyethylene (PE) fibers were used to prepare ambient cured fly ash‐slag‐based engineered geopolymer composites (EGC). The effects of fiber types and fiber volume fractions (1.5%, 1.75%, 2.0%, 2.25%, and 2.5%) on the compressive strength and tensile performance of EGC were evaluated. It was found that by increasing the fiber volume fraction from 1.5% to 2.5%, L‐PVA fibers had the lowest influence, whereas PE fibers had the highest influence on the compressive strength of EGC. The optimum fiber volume fractions of L‐PVA, H‐PVA, and PE fibers were 1.75%, 2.25%, and 1.5%, respectively, for EGC to achieve the best tensile performance. Scanning electron microscope (SEM) investigations showed that the bonding performance of PE fibers to the EGC matrix was higher than those of L‐PVA and H‐PVA fibers to the EGC matrix. [ABSTRACT FROM AUTHOR]

The effect of Melaleuca cajuputi leaf extract (MCLE) on the biochemical and innate immunity of Macrobrachium rosenbergii was observed during the toxicity test. Thereafter, the sensitivity of MCLE against Probopyrus buitendijki was investigated. Firstly, the MCLE phytochemical compounds were analyzed using gas chromatography-mass spectrometry (GC-MS). Then, the MCLE solution was formulated at 0.00 (control), 0.28, 0.57, and 0.85 g/L, exposed to M. rosenbergii, and their biochemical and immunity responses were recorded after 3 days. The MCLE concentration was prepared based on the LC50 value that had been determined earlier. With the same MCLE concentrations, the sensitivity of MCLE against adult male, female, and larvae P. buitendijki was observed after 1 h of exposure using a scanning electron microscope (SEM). The results revealed the presence of 2-isopropyl-10-methylpenanthrene, phenanthrene, 1-methyl-7-(1-methyl ethyl)-, and 4H-1-benzopyran-4-one, 3-acetyl-5, 7-dihydoxy-2-methyl to be the major compounds in MCLE. A significant elevation (p<0.05) of the total protein (TP), alkaline phosphatase (ALP), and phenol oxidase (PO) activities of M. rosenbergii exposed to MCLE was observed compared to control. The total hemocyte count (THC), granular cells (GC), and hyaline cells (HC) were also increased (p<0.05) in MCLE-treated M. rosenbergii. All adult males, females, and eggs of P. buitendijki were dead after 1 h of exposure. Light damage including size reduction was observed in adult male and female P. buitendijki at 0.28 g/L MCLE, while their eggs were shrunken and some of them ruptured. Severe damage was observed in all adult male and female P. buitendijki at 0.85 g/L MCLE, with dented dorsal surfaces, and all eggs were ruptured. Findings indicated the potential of MCLE to improve immunity and health of M. rosenbergii, as well as act as an anti-parasitic agent against P. buitendijki. [ABSTRACT FROM AUTHOR]