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The main goal of this study is to assess the mechanical, physical and morphological properties of bundle fibers extracted from curaua leaves and pullout testing in cementitious matrix. The mechanical properties of the fibers were analyzed in mechanical testing of four fiber lengths (10, 20, 30 and 40 mm) to observe the influence of the length of the variable's tensile strength, Young's modulus and Weibull modulus. Pullout testing was measured frictional and maximal force. Fibers physical properties were assessed by means of the multipycnometer method. Morphological analyses were conducted through optical and scanning electron microscopes. The results showed that the fiber length does not interfere with the tensile strength (507–638 MPa) and Weilbull modulus (8–12). However, it influences the Young's modulus (19–39 GPa). Curaua bundles present a higher resistance to rupture and Young's modulus than other plant fibers species and it seems to be related to the distribution of faults along the beam. The fibers morphological characterization showed a rough and irregular surface with some impurities which are associated with the surface of the fibrous bundle and low adherence (0,26–0,47 N) with cementitious matrix in pullout testing. [ABSTRACT FROM AUTHOR]

This research paper focuses on the use of solid biomass waste, specifically a combination of Polyalthia longifolia seed (PLSF) and graphite (GH) powder, as reinforcements in vinyl ester (VE) composites. The composites were produced via the hand layup method, with the filler concentration varying from 0 to 15 wt% of PLSF and 0–9 wt% of graphite. The objective was to examine the influence of the hybrid filler on the mechanical characteristics of the composites. The mechanical properties of composites prepared from P. longifolia seeds and graphite powder were experimentally characterized. These properties included tensile strength, flexural strength, impact resistance, and hardness. The hybrid composite had a maximum tensile strength of 48.4 MPa, and its tensile modulus was 1.66 GPa. The hybrid filler at 15% wt% of PLSF and 6% of graphite has the highest flexural strength, which is around 148 MPa. The ultimate impact strength and hardness were measured to be 41.3 kJ/m2 and 44.5, respectively, after the addition of 15 and 6 wt% of hybrid filler. In comparison to neat vinyl ester resin, the PLSF/GH‐VE composites exhibited an increase in tensile, flexural, impact, and hardness of 2.69, 1.82, 3.03, and 1.59 times, respectively. Hybrid composite surfaces were analyzed using scanning electron microscopes to determine surface characteristics and fractured surfaces. In addition, the PLSF/GH‐VE composites have been utilized in the production of components for four‐wheelers. Highlights: Investigated the impact of hybrid filler‐reinforced vinyl ester composites.Mechanical and thermal properties were experimentally characterized.Surface characteristics and fractured surfaces were examined.PLSF/GH‐VE composites are used in producing components for four‐wheelers. [ABSTRACT FROM AUTHOR]

This study investigated the microstructure, hardness, tensile and tribological behaviour of a cooling slope Al--Si--Mg alloy following ECAP and T6 heat treatment. The optical and scanning electron microscopes were applied to investigate the microstructure of the as-cast material and heattreated ECAPed Al--Si--Mg alloy. The dry sliding wear test was tested with three different loads of 10 N, 50 N, and 100 N with constant sliding speed and sliding distance at 1.0 m/s and 9000 m, respectively, using the pin-on-disc tribometer. The hardness and tensile properties were evaluated through microhardness, UTS, and YS measurement for the as-cast Al--Si--Mg alloy, both heat-treated with and without ECAPed alloys. Moreover, wear rate and COF in the Al--Si--Mg alloy with different loads were analysed and linked with microstructural and strength behaviour after the ECAP process. Meanwhile, these analyses of results were correlated with the behaviour of the as-cast Al--Si--Mg aluminium alloy and heat-treated non-ECAPed alloy. Results demonstrated that a combination of ECAP processing and T6 heat treatment improves the mechanical behaviour, while the COF and wear rate are improved at a load of 100 N. [ABSTRACT FROM AUTHOR]

Scanning electron microscopes (SEMs) are a popular analytical tool due to their high spatial resolution, large depth of field, and analytical capabilities. However, in many cases, the large-scale installation and cost of SEMs can be a barrier to entry for smaller laboratories or facilities. The introduction of a more compact benchtop SEM has changed the landscape, enabling scientists in many fields to adopt the technology and revolutionize research. Benchtop SEMs can be used in a variety of industries including materials science, pharmaceutical research, energy exploration, science education, and academia. These industries require analysis at the nanoscale for quality control, failure analysis, and R&D, for all of which the benchtop SEM is perfectly positioned to provide necessary detail. These advantages and new developments in the technology have made the benchtop SEM a widely available and well-accepted tool. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effect of isopropyl triisostearoyl titanate (KR-TTS) as a titanate coupling agent (TCA) on surface modification of TiO2 nanotube (TNT) material. From the physical and chemical studies that have been performed on the modified TiO2 nanotube, scanning electron microscope micrographs, energy-dispersive X-ray and viscosity indicated that there was significant reduction in particle aggregation of the modified TiO2 Nanotube. FTIR spectroscopy confirmed that the functional group of the TCA reacted with the hydroxyl groups present on the surface of TiO2 nanotube resulting in an altered surface property from being hydrophilic to hydrophobic. X-ray diffraction indicated that crystalline structure did not change upon the modification with the coupling agent. Isopropyl triisostearoyl titanate (KR-TTS) is found to be superior in performance and has a significant effect on the dispersion and resolving of agglomeration. This paper presents the effect of surface modification with the TCA of isopropyl triisostearoyl titanate (KR-TTS) type on the TiO2 nanotube material. [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]

Due to the unique functional properties of shape memory alloys (SMAs) and current scientific interest in Cu-containing biomaterials, a continuously cast Cu-Al-Ni alloy in the form of rods has been investigated as a potential candidate for biomedical application. Additionally, the fact that Cu- complexes have an antitumour effect served as a cornerstone to develop more efficient drugs based on trace element complexes. In line with that, our study aimed to analyse the basic properties of the Cu-Al-Ni alloy, along with its anticancer properties. The detailed chemical analysis of the Cu-Al-Ni alloy was performed using XRF and SEM/EDX analyses. Furthermore, a microstructural and structure investigation was carried out, combined with hardness measurements using the static Vickers method. Observations have shown that the Cu-Al-Ni microstructure is homogeneous, with the presence of typical martensitic laths. XRD analysis confirmed the presence of two phases, β′ (monoclinic) and γ′ (orthorhombic). The viability of osteosarcoma cells in contact with the Cu-Al-Ni alloy was evaluated using epifluorescence microscopy, while their morphology and attachment pattern were observed and analysed using a high-resolution SEM microscope. Biocompatibility testing showed that the Cu-Al-Ni alloy exerted a considerable antineoplastic effect. [ABSTRACT FROM AUTHOR]

The goal of this work is to examine the effect of hot deformation on shrinkage porosity and nonmetallic inclusions in an AISI 1070 grade steel industrially produced wheel casting. Steel cleanliness is an important consideration as it influences the mechanical properties of the final product. A high density of porosity and inclusions have been shown to be detrimental for mechanical properties, especially during hot rolling. Using a laboratory-scale rolling mill, cast preforms were subjected to a 66% cumulative reduction to determine the effect of thermomechanical processing on void closure and inclusions that may produce anisotropy in mechanical properties. Quantitative automated feature analysis, AFA, of inclusion type, size, morphology, and distribution was conducted utilizing an Aspex PICA 1020 scanning electron microscope to determine differences in inclusions and shrinkage porosity in the as-cast and as-rolled conditions. The results were compared with previously reported impact toughness values which indicated a trend with MnS projected length and average impact toughness in the T-L orientation. Reduction in shrinkage porosity was also verified utilizing 3D micro-X-ray CT scans. The AFA results showed a decrease in shrinkage porosity from 177 ppm in the as-cast condition to less than 35 ppm after rolling. Pores were in general much smaller and widely distributed after hot rolling and this would suggest improved impact properties. Analysis of nonmetallic inclusions revealed three primary categories of inclusions that included MnS, Al2O3, and complex inclusions that mainly consisted of MnS with an Al2O3 core, with small quantities of mixed silicates of Mn and Al and calcium aluminates (CaAl2O4). [ABSTRACT FROM AUTHOR]

This paper focuses on the evaluation of the strength development and microstructure of nano-calcium carbonate (CaCO3) cemented paste backfill experimentally cured under isothermal conditions at room temperature and non-isothermal conditions in the field. A series of mechanical (uniaxial compressive strength, UCS) and microstructural (thermogravimetric, mercury intrusion porosimetry, scanning electron microscope) tests as well as monitoring experiments are experimentally conducted on cemented paste backfill (CPB) specimens with and without nano-calcium carbonate and cured at different times and under isothermal or non-isothermal conditions. The results show that the addition of nano-CaCO3 particles to CPB significantly improves its mechanical strength, irrespective of the thermal curing conditions (isothermal, field non-isothermal conditions). However, the impact of nano-CaCO3 particles on the increase in strength of CPB is only effective or significant at the early ages (curing time≤7 days). It is also found that the higher temperatures improve the accelerating effect of nano-CaCO3 much more than they accelerate the PCI hydration reactions in the first 3 days. Moreover, it is also found the sulphate ions present in the natural gold tailings negatively affect the mechanical performance of nano-CPB and reduced the accelerating effect of nano-CaCO3 due to sulphate attacks. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of methyl red dye using Mn(5%) doped CdS nanoparticles was studied. Mn doped CdS nanoparticles was synthesized by microwave assisted solvo thermal method where the chemicals used wereCadmium Acetate [(CH3COO)2Cd, H2O], Manganese Chloride [MnCl2.2H2O] and Sodium Sulfide [Na2S.xH2O]. X-Ray diffraction(XRD) analysis was carried out in order to analyze the structural dimensions of the synthesized nanoparticles and the average crystallite size has been calculated at the full width half maximum (FWHM) of the diffraction peaks using Debye-Scherer equation and it was found to be around2.3nm. FTIR spectra analysis was done in order to analyze different functional and vibrational groups present in the as synthesized sample of Mn doped CdSnanoparticles. The morphology of sample wasstudied by scanning electron microscope. The aqueous solution of methyl red[C15H15N3O2] has been prepared and was mixed with the as synthesized Mn doped CdSnanoparticles and was exposed for photocatalytic degradation using 100 W bulb. UV-visible spectra of the light irradiated methyl red solutions were studied at different interval of time and no red shift was observed with increase of exposure time. The intensity of the absorption peak was also found to be reduced with the increasing time interval. The photo degradation of methyl red dye was observed up to 90% at the exposure time of 90 minutes. [ABSTRACT FROM AUTHOR]

Spore balls of false smut of rice caused by Ustilagonoidea virens were collected from different major rice belts of eastern part of India. Ten isolates from ten different locations were collected and isolated in the laboratory for their, cultural, morphological and molecular characterization. Potato sucrose agar media was used for their cultural studies and observation on colony diameter, colour and sporulation were made. Spores of all the isolates were observed under scanning electron microscope (SEM) and light microscope for spore size, spine length and colour. Differences in colony characters were observed where the highest mycelial growth was observed in isolate Uv2 with 5.33 cm colony diameter and lowest mycelial growth was observed in Uv9 (3.70 cm). Most of the isolates produced white and circular colony. Spores of all the isolates observed under a light microscope appeared to be olive green in colour, however, a significant variation in spore size and spike length under SEM was observed. Spores size and spike length of different isolates ranged between 4.533 μm to 6.169 μm and 362.567 nm to 799.533 nm, respectively. For genetic identification and variability, DNAs of isolates were amplified using ITS1 and ITS 4 primers. The length of nucleotide sequences of different isolates varied from 583 to 606 bp. Phylogenetic analysis revealed genetic variation among the isolates, dividing them into two major groups. [ABSTRACT FROM AUTHOR]

The effectiveness of corrosion inhibition based on the organic compound 2,7-dimethyl-2,7-dicyanide-3,6-diazaoctan (MAD-20) was studied on low-carbon steel in 15% H2SO4 solution. The samples were exposed in a 15% H2SO4 solution without an inhibitor and with different concentrations of MAD-20 inhibitors. Weight loss measurements, scanning electron microscope (SEM) were used to study the inhibitory effects of MAD-20. It has been shown that the MAD-20 inhibitor is an effective inhibitor of acid corrosion. [ABSTRACT FROM AUTHOR]

In this work, A356 alloy samples having a dimension of 4 × 2 0 × 2 0 mm were coated by hard anodic oxidation method at eight different thicknesses up to ∼ 80 μ m. The sample surfaces and longitudinal section of these surfaces in both coated and uncoated conditions were investigated with a scanning electron microscope (SEM). Microhardness of the coating layers and core regions (base metal) were determined with the microvickers hardness testing method. Corrosion properties of the coated and uncoated samples were investigated by an electrochemical corrosion test set up according to ASTM G5 standard. The test results obtained from the coated and uncoated surfaces were compared to each other. Coated surfaces exhibited fluctuant surface profile. Microcracks were formed on these surfaces. Microhardness of the coating layers increased with increasing coating layer thickness. Energy dispersed X-ray spectroscopy (EDS) analysis of the surfaces showed that oxygen rate on the surfaces increased after the corrosion tests. Corrosion rate of the A356 alloy coated by hard anodic oxidation decreased with increasing coating thickness up to 40–50 μ m, but after this coating thickness, the corrosion rate increased. The results obtained from the investigations were discussed based on the characteristics of the coated surfaces. [ABSTRACT FROM AUTHOR]

The current research work attempted to investigate the strontium oxide nanoparticles (SrONPs) synthesized from the Lantana camara leaf extract. The bio-synthesized strontium nanoparticles were characterized by a UV-Visible spectrometer, Fourier Transform Infra-Red spectra (FTIR), Scanning Electron Microscope, X-Ray diffraction, and Dynamic Light Scattering. The biomolecules in the extraction of plant leaves behaved as good reducing and capping agents. The XRD peaks are indexed to 13.020, 22.240, 25.940, 31.310, 34.000, and 40.910, and the corresponding planes are (101), (112), (202), (213), (310), and (312) representing cubic structure for SrNPs. The strontium nanoparticles are unevenly globular in shape, and chaos, and exhibited cluster and partially even surfaces shown from the Scanning Electron Microscope. The antibacterial assay of the synthesized Lantana camara strontium oxide nanoparticles was evaluated. The binding effect was more at higher concentrations (100 µl) than the control for the species E. coli (21 mm), and A. niger (20 mm). [ABSTRACT FROM AUTHOR]

The deep mixing method is considered one of the most popular ground improvement techniques, which cement is commonly used as a cementitious material. However, the use of cement resulted in high cost and high carbon footprint. Utilizing bottom ash, a by-product from electricity power plant, as a green stabilizer material is of interest. This paper studied the effect of bottom ash and ground bottom ash on the properties of cement stabilized soft Bangkok clay. The variables included initial water content, clay/binder ratio, cement/BA ratio, and curing time. The unconfined compressive strength test, scanning electron microscope, cost, and CO2 emission were assessed. The results showed that the strength decreased with the increase in initial water content because of the bleeding effect and poor particle bonding. The mixes with 10%BA and 10%GBA achieved the highest 7-day and 28-day strengths for all clay/binder ratios. The strength of sample with GBA was higher than that with BA due to the higher reactivity of the GBA. For BA, the mixes with 60clay/40binder exhibited sufficient strength passing the Thailand's Department of Highways requirement for cement column materials. In the case of GBA, the lower binder content mix with 70clay/30binder met the strength requirement. According to the SEM analysis, the improvement of the matrix was observed and confirmed the higher pozzolanic reaction of GBA and the resulting higher strength from the higher surface area. This research thus showed that the cement-BA could be used as a low-cost and low-carbon binder for the stabilization of clay. [ABSTRACT FROM AUTHOR]

The problems of measuring the dimensions of relief elements on a scanning electron microscope (SEM) in the technological process of manufacturing microcircuits are considered. The first problem is related to the fact that the increase in the SEM during operation can vary over a wide range depending on the measured dimensions. The second problem is that the probe diameter determined in the SEM calibration process differs from the diameter used in operational measurements. The third problem is related to the fact that it is not known which relief parameter is measured in the SEM probe defocusing method. It is shown that to solve the first problem, it is necessary to calibrate the mark on the image using structures with a trapezoidal profile and large angles of inclination of the side walls. The solution of the second problem is based on the method of defocusing the SEM probe: determining the dependence of the sizes between certain points on the SEM signals on the probe diameter and extrapolating this dependence to the zero value of the diameter. The third problem is solved with the help of a virtual scanning electron microscope. [ABSTRACT FROM AUTHOR]

Summary: Stegelletina salinaria is redescribed from Spain and South Africa. Spanish material was collected in sandy soil from the type locality and a nearby area, while one population collected in compost was examined from South Africa. The species is characterised by its small size (0.27-0.41 mm), lateral field with three incisures, lip region with three pairs of dentate lips bearing four tines each, primary axils bearing a large guarding process, secondary axils lacking guarding processes, nerve ring and secretory-excretory pore at isthmus level, spermatheca and post-vulval uterine sac poorly developed, female tail conoid with rounded hyaline terminus and males unknown. The description, light micrographs and scanning electron microscope images, illustrations and molecular analyses are provided. 18S and 28S rDNA sequence analyses show that the isolates of S. salinaria from Spain and South Africa are closely related to each other and to other species of Stegelletina , while also indicating a close relationship with some species of Nothacrobeles , Scottnema and Stegelleta (28S tree) and Zeldia (18S tree). [ABSTRACT FROM AUTHOR]

Adhesion it is known that the bond strength varies depending on the interaction of the material surfaces with each other and the surface morphology of the samples. Sufficient surface conditions are required to achieve good adhesion. It is important how the surface morphology, roughness values and free surface energy (SFE) values affect the bond strength and the relationships between these values. The aim of this study was to investigate the relationship between surface morphology, roughness values, contact angle and SFE values of hybrid etched surfaces with chemical etching, sandblasting and both sandblasting and chemical etching. Different surface morphologies were formed of the surfaces etched with different techniques. Contact angle values were determined by using different liquids on the surface of the samples with different surface morphologies. In addition, the surface morphology of the etched AA7075 samples was analyzed by scanning electron microscope (SEM) and 3D profilometer, and surface roughness values were determined.Different surface morphologies of the etched surfaces were formed by different techniques. The SFE values of the surfaces give us information about how wettable the surface is. For this reason, the surface roughness andn SFE values of AA7075 surfaces were compared and the mechanical and thermodynamic relations of the surfaces were revealed in the study. OWRK and Zisman methods were used in the calculations of SFE and it was seen that the values obtained from the two methods were consistent with each other. The highest SFE values were obtained on hybrid etched surfaces with sandblasting+0.5M NaOH and sandblasting+1M NaOH. Surface roughness values took different values in each surface treatment. As a result, it is seen that there is no direct relationship between surface roughness values and SFE. [ABSTRACT FROM AUTHOR]

An in situ ion irradiation scanning electron microscope (I3SEM) has been developed, installed, and integrated into the Ion Beam Laboratory at Sandia National Laboratories. The I3SEM facility combines a field emission, variable pressure, scanning electron microscope, a 6 MV tandem accelerator, high flux low energy ion source, an 808 nm-wavelength laser, and multiple stages to control the thermal and mechanical state of the sample observed. The facility advances real-time understanding of materials evolution under combined environments at the mesoscale. As highlighted in multiple examples, this unique combination of tools is optimized for studying mesoscale material response in overlapping extreme environments, allowing for simultaneous ion irradiation, implantation, laser bombardment, conductive heating, cooling, and mechanical deformation. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to incorporate hydroxyapatite nanoparticles (nHA) or amorphous calcium phosphate nanoparticles (nACP) into a self-etch primer (SEP) to develop a simplified orthodontic bonding system with remineralizing and enamel preserving properties. Materials and Methods: nHA and nACP were incorporated into a commercial SEP (Transbond™ plus) in 7% weight ratio and compared with the plain SEP as a control. Shear bond strengths (SBS), enamel damage, and adhesive remnant index (ARI) scores were evaluated at 24 h and post 5000 thermocycling. Field-emission scanning electron microscope (FESEM) was used to inspect the distribution of the nanoparticles in the experimental SEPs and evaluate the enamel surface integrity both before bracket bonding and post bracket debonding. Phase determination and remineralizing capability of the modified SEP were characterized by X-ray diffraction and Raman spectroscopy, respectively. Results: The addition of nHA or nACP to the SEP significantly reduced the SBS, ARI, and enamel damage (p < 0.05) as compared to the control SEP; however, only nHA-SEP survived the thermocycling protocol and yielded acceptable SBS (13.38 MPa). Enamel remineralizing ability of the developed nHA-SEP was confirmed by both FESEM images and Raman phosphate map. Conclusions: Incorporating nHA into SEP resulted in clinically acceptable bond strengths with remineralizing ability. Clinical relevance: The newly developed nHA-SEP has unprecedented ability to simultaneously etch, prime, and remineralize the enamel in a single step leaving immaculate enamel surface with the potential of saving cost and time at the post-debonding step. [ABSTRACT FROM AUTHOR]

Thermoplastic composite sheets have great potential for use in industrial applications owing to their fast-forming properties in the mold. One of the important matters of forming is the tendency of the part to recover elastically after it comes out of the mold. This behavior affects the dimensional accuracy of the final part. In this study, V-bending experiments were carried out to understand the spring-back phenomenon of continuous glass fiber-reinforced polyamide- 6 composite sheets. Unidirectional and cross-ply composite sheets were used in the experiments and bending angle, die radius, pressure, and dwell-time were investigated systematically. After bending, the spring-back angles of the parts were measured and the effects of the inspected parameters were compared. Also, variations in part thickness caused by springback were evaluated. Finally, the deformations in the specimens resulting from the residual stress were visualized with a scanning electron microscope. When the results were compared, it was determined that the bending conditions where the spring-back defect could be minimized were 6 mm radius, 90° angle, 120 s dwell-time, and 3 MPa pressure. Under these situations and in sheets bent 90°, the amount of spring-back was determined as 22° for unidirectional composites and 15° for cross-ply composites. [ABSTRACT FROM AUTHOR]

This work investigates the microstructure characterization and mechanical properties of Al alloy fabricated by additive friction stir deposition (AFSD). Microstructure characterizations of the Al alloy 5B70 base material (BM) and build were compared using optical microscope (OM) and electron back scattered diffraction (EBSD). The hardness distribution in the direction perpendicular to the cross-section of the deposited area was systematically evaluated. Tensile tests were performed on the BM and the build using digital image correlation (DIC), and the real-time stress distribution states of the specimens were analyzed. After the tensile tests, the fracture micromorphology was characterized using scanning electron microscope (SEM). The results indicated that a high degree of recrystallization occurred in the deposition zone, where fine, equiaxed, and differently oriented grains are formed. It was found that the strength of the deposition layer was lower compared to that of the BM, but its toughness was significantly improved. Also, obvious anisotropy of mechanical properties was identified in the deposition layer. [ABSTRACT FROM AUTHOR]

The effects of the wet–dry cycles on the chemical compositions, microstructure, and mechanical properties of Pisha sandstone were experimentally investigated in the current study. A series of uniaxial compression tests were conducted to validate the deterioration of the mechanical property of specimens after wet–dry cycles. In addition, the evolutions of the mineral compositions and microstructure characteristics were confirmed by X-ray diffraction (XRD) and scanning electron microscope (SEM). Experimental results indicated that with the increase of wet–dry cycles, the mechanical properties of Pisha sandstone gradually decrease. After five wet–dry cycles, the uniaxial compressive strength, elastic modulus, and fracture energy of specimens were reduced by 41.06%, 62.39%, and 31.92%, respectively. The failure mode of the specimen changes from inclined shear failure to peel failure. Compared to the initial specimens, the relative content of primary minerals after five wet–dry cycles declined by 5.94%, and the relative content of clay minerals after five wet–dry cycles increased by 54.33%. Additionally, the porosity of samples exhibits a positive correlation with wet–dry cycles. Compared to the initial specimens, the porosity of specimens after five wet–dry cycles increased by 176.32%. Finally, a prediction model of the correlation between uniaxial compressive strength and porosity is proposed and verified. [ABSTRACT FROM AUTHOR]

Thermoplastic composite sheets have great potential for use in industrial applications owing to their fast-forming properties in the mold. One of the important matters of forming is the tendency of the part to recover elastically after it comes out of the mold. This behavior affects the dimensional accuracy of the final part. In this study, V-bending experiments were carried out to understand the spring-back phenomenon of continuous glass fiber-reinforced polyamide-6 composite sheets. Unidirectional and cross-ply composite sheets were used in the experiments and bending angle, die radius, pressure, and dwell-time were investigated systematically. After bending, the spring-back angles of the parts were measured and the effects of the inspected parameters were compared. Also, variations in part thickness caused by spring-back were evaluated. Finally, the deformations in the specimens resulting from the residual stress were visualized with a scanning electron microscope. When the results were compared, it was determined that the bending conditions where the spring-back defect could be minimized were 6 mm radius, 90° angle, 120 s dwell-time, and 3 MPa pressure. Under these situations and in sheets bent 90°, the amount of spring-back was determined as 22° for unidirectional composites and 15° for cross-ply composites. [ABSTRACT FROM AUTHOR]

This paper presents the possibilities of applying atomic force microscopy (AFM) techniques to the study of the wear of prosthetic biomaterials. In the conducted research, a zirconium oxide sphere was used as a test piece for mashing, which was moved over the surface of selected biomaterials: polyether ether ketone (PEEK) and dental gold alloy (Degulor M). The process was carried out with constant load force in an artificial saliva environment (Mucinox). An atomic force microscope with an active piezoresistive lever was used to measure wear at the nanoscale. The advantage of the proposed technology is the high resolution of observation (less than 0.5 nm) in the three-dimensional (3D) measurements in a working area of 50 × 50 × 10 µm. The results of nano wear measurements in two measurement setups are presented: zirconia sphere (Degulor M and zirconia sphere) and PEEK were examined. The wear analysis was carried out using appropriate software. Achieved results present a tendency coincident with the macroscopic parameters of materials. [ABSTRACT FROM AUTHOR]

Ground improvement using sustainable and environmentally friendly agents have been the focus of research in the recent years. Biological stabilization is one of the emerging techniques in this field which aims at enhancing the engineering properties of soil through enzyme treatment. This technique eliminates the use of conventional resources and improves the economic aspects of construction projects. This paper explores the potential of bio-enzymatic stabilization in attaining the permanency in the strength of the lateritic pavement subgrade which, in turn can potentially contribute to the development of pavement design guidelines. The economic viability and longevity of bio-modification through different dosages as well as curing periods are studied and the results are compared. In this study, correlation is established between CBR and unconfined compressive strength of bio-modified soil with reference to the soil properties. The bio-enzyme is found to increase the unconfined compressive strength and resilient modulus of lateritic soil. At higher curing periods, the rutting life of enzyme treated lateritic pavement is found to increase while the damage ratio decreases. X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) studies have been performed in the present work to understand the microstructural behavior of enzyme treated soil. Cost analysis is also carried out in the present work to understand the economic feasibility of enzymatic stabilization. The cost analysis studies indicate a reduction in the rutting of pavement, which contributes to a longer service life of enzyme treated lateritic pavement. [ABSTRACT FROM AUTHOR]

A physical crosslinking strategy based on hydrogen bonding interaction was developed to prepare image-recording layers derived from carboxyl-containing polymer latexes, a hydrophilic amine-oxide-substituted polymer, and a water-soluble IR-absorbing dye. Carboxyl-containing polymer latexes were prepared by emulsion copolymerization of mono-2-(methacryloyloxy)-ethyl phthalate, styrene and acrylonitrile. A water-soluble amine-oxide-containing polymer (O-PDMAEA) was prepared by aqueous polymerization of 2-(dimethylamino) ethyl acrylate followed by oxidation with hydrogen peroxide. The hydrogen bonding interaction between the polymer latex particles and the O-PDMAEA and its effects were studied. Coating solutions comprising the polymer latex and the O-PDMAEA were prepared and applied to the aluminum lithographic substrate by spin-coating to obtain the image-recording layers. After they were exposed to 830 nm infrared laser light and developed with water, a visible image on the substrate could be obtained. The properties of the image-recording layers were evaluated by scanning electron microscope, water contact angle analyzer, inspection of the image quality and adhesion test. Results showed that both the image quality and adhesion of the image to the substrate were improved by introducing hydrogen bonding interaction. [ABSTRACT FROM AUTHOR]

From the point of view of a facility director, I am unable to commit funds towards software tools that include vendor lock. B Statement Against Vendor Lock in Proprietary Formats b Confocal Listserver I Hi everyone, I recently had a discussion with a vendor about analysis software with vendor lock in the exported data file formats. This means that it is essential to be able to both import and export data from every tool in a portable format with as much metadata as possible intact. This makes buying software with vendor-locked file formats an unacceptable position for an imaging facility. [Extracted from the article]

This work reports the synthesis of two novel polyhedral oligomeric silsesquioxane (POSS) hybrid particles by investigating the effects of different crosslinking agents on morphology, porosity, chemical structure, crystalline properties, and thermal behavior of the resultant products. The hydrophilic glycerol dimethacrylate and hydrophobic ethylene glycol dimethacrylate (EGDMA) were used as co-monomer and crosslinking agents to obtain novel poly(POSS-co-GDMA) and poly(POSS-co-EGDMA) hybrid spherical microparticles by step-wise Pickering-like seeded polymerization. The crosslinking agent played a key role in specific surface area (SSA), average pore size, and pore volume, characterized by Brunauer–Emmett–Teller and Barrett–Joyner–Halenda analysis. When poly(POSS-co-GDMA) possess 88.0m2/g SSA, poly(POSS-co-EGDMA) has 3.5m2/g. Both particles exhibit a homogenous spherical shape in the polydisperse form and hybrid organosilica structure defined by scanning electron microscope, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy. The hybrid particles showed an amorphous silica composite character with thermal resistance up to 420 °C, determined by X-ray diffraction and thermogravimetric analysis. The mesoporous hybrid POSS particles could have great potential for many advanced material applications. [ABSTRACT FROM AUTHOR]

The structure of water-soluble imidazoline amide molecule was optimized by using GaussView 6 and Gaussian 16 software， and the energy difference was obtained through orbital energy calculation. According to the energy difference， the corrosion inhibition mechanism was revealed, and the corrosion inhibition mechanism of water-soluble imidazoline amide on A3 steel was further revealed. At the same time, the corrosion inhibition performance of water-soluble imidazoline amide on A3 steel in hydrochloric acid medium was studied by rotating coupon test, electrochemical method and scanning electron microscope. The results show that the optimum amount of water-soluble imidazoline amide is 15 mg/L in dilute hydrochloric acid solution with corrosion medium of 1 mol/L and at 45 ± 1 ℃, and the corrosion inhibition rate is as high as 96.8%; The polarization curve of electrochemical test is consistent with the results of rotating coupon test. It can be seen by scanning electron microscope that water-soluble imidazoline amide has significant corrosion inhibition effect on A3 steel. [ABSTRACT FROM AUTHOR]

The purpose of this work is to study the influence of thermal effect on the surface morphology of the Fe–Cr–Al (Kh15Yu5) alloy foil and the elemental composition of the surface layers. Also, studies have been carried out on the physicochemical characteristics of the primary support with the deposited secondary support in the initial state and within the temperature range from 25 to 900 °C. The research was carried out on a JSM 6610 LV, JEOL scanning electron microscope with an installed INCA Energy 450 energy-dispersive microanalysis system. Before depositing secondary support (aluminum oxide), for a stronger adhesion to the foil metal, the foil surface was pretreated with a phosphating solution. It was found that during heating up the elemental composition of the surface layer of the Kh15Yu5-alloy foil does not remain constant and depends on the mode of thermal effect. This implies the possibility of changing the adhesion and adsorption properties of the foil surface, as well as the need to take this into account when depositing secondary support and an active phase to the foil. Studies have shown that the applied methods for phosphatizing and depositing secondary support to the foil surface make it possible to obtain a quite resistant coating. No peeling of the secondary support from the foil surface is observed during high-temperature treatment in the air. [ABSTRACT FROM AUTHOR]

Vitex negundo has ecological, ornamental, medicinal, and practical values. However, in the establishment of the rapid propagation system of Vitex negundo, it was found that the contamination rate of seeds in the process of sterile germination was extremely high, reaching 50%-75%. In this study, in order to reduce its contamination rate in the process of sterile germination of Vitex negundo seeds, by identifying its main contaminating strains, and screening out effective fungistatic agents, tissue separation method was used to isolate and purify the contaminating fungi. Simultaneously, the cytological observation of the conidia of the contaminating fungi was carried out by light microscope and scanning electron microscope. Then the universal primers of the Internal Transcribed Spacer(ITS) sequence of the fungal rDNA gene were used for molecular identification. Finally, four fungicides, including chlorothalonil, mancozeb, carbendazim, and Flumorph-Mn-Zn were added to the PDA medium for analysis of antifungial effect. The results showed that the main contaminating fungi were the fungi located on the surface of the seeds. The colonies were yellowish-green concentric circles in velvety shape. The mycelia were septum brown branching bacteria, and the conidia were olive brown, septum and clostridial form. Cytological and molecular biological identifications indicated that the contaminating fungus was Alternaria alternata. The antifungial study showed that 60% of Flumorph-Mn-Zn had the best inhibitory effect on Alternaria alternata. and the colony diameter was the smallest. The contamination rate was significantly reduced to 5.5%, when 60% of Flumorph-Mn-Zn was diluted 1 400 times and added to the sterile germination medium(water agar medium) of Vitex negundo seeds. In conclusion, the main contaminating fungus in the sterile germination of Vitex negundo seeds was Alternaria altemate, 60% of Flumorph-Mn-Zn had the best inhibitory effect on it. [ABSTRACT FROM AUTHOR]

The present work was designed to investigate the microscopic structure of the oesophagus in the southern white‐breasted hedgehog (Erinaceus concolor) using histochemical staining, Scanning electron microscope (SEM), and stereological procedures. Four adult males were included in our study. Serial sections of the entire length of the oesophagus were stained with aldehyde fuchsin, alcian blue (pH 2.5), Periodic acid Schiff (PAS), and Masson's trichrome. Then, the total volume of the oesophagus, and the total volume of its different layers, were estimated using Cavalieri's principle. The oesophageal epithelium was a non‐keratinized stratified squamous type. Muscularis mucosa was present as a thick layer between lamina propria and submucosa and its thickness was increased toward the stomach. Tunica submucosa was a loose connective tissue containing an oesophageal gland with PAS‐positive and AB‐positive reactions throughout the submucosa and become denser toward the stomach. The tunica muscularis consisted of two distinct striated muscle layers, and its thickness was decreased toward the stomach. On SEM images, the cervical and thoracic oesophagus showed shallow folding, while the abdominal part had deeper folds. The present findings indicate that the histological properties of the oesophagus in southern white‐breasted hedgehogs have slight similarities with rodents and considering its epithelium, submucosal glands and tunica muscularis more resemble with dog oesophagus. The obtained results may be quite helpful to improve the current knowledge of the histophysiology of the hedgehog gastrointestinal tract as a member of eulipotyplan mammals and as a pet for biologists and veterinarians. [ABSTRACT FROM AUTHOR]

This investigation was led to depict the structural and functional adaptations of the oral cavity of herbivorous Egyptian tortoises using scanning electron and light microscopes. The SEM showed that the triangular papillary tongue possessed three conical papillary subtypes: the rectangular conical on the tip, the round conical on the rest of the dorsal lingual surface and the elongated conical on the caudal portion of the lingual wing. The presence of the serrated lips with their valves compensated for the absence of the teeth. The rostral part had a vomeronasal opening while the middle part had the choana, but the caudal part had numerous openings of the salivary glands. There are three palatine folds: a single median palatine fold, two peripheral palatine folds and the choanal fold. The current histological results show the keratinized dorsal lingual surface, in which the keratinized layer extended to cover the papillae. Two types of lingual glands, according to their position, are papillary superficial and deep lingual glands. Papillary or superficial glands open in the interpapillary spaces via narrow openings, while the deep glands are surrounded by well‐developed muscles and open via wide openings on the dorsal lingual surface. An entoglossal cartilaginous structure of hyaline cartilage was found in the mid‐ and hindtongue, with numerous chondrocytes lodged within the lacunae. Our results conclude that the oral cavity of the herbivorous Egyptian tortoise was adapted to the dietary and vigorous demands of the Egyptian fauna. [ABSTRACT FROM AUTHOR]

When impinging on optical structures or passing in their vicinity, free electrons can spontaneously emit electromagnetic radiation, a phenomenon generally known as cathodoluminescence. Free-electron radiation comes in many guises: Cherenkov, transition, and Smith–Purcell radiation, but also electron scintillation, commonly referred to as incoherent cathodoluminescence. While those effects have been at the heart of many fundamental discoveries and technological developments in high-energy physics in the past century, their recent demonstration in photonic and nanophotonic systems has attracted a great deal of attention. Those developments arose from predictions that exploit nanophotonics for novel radiation regimes, now becoming accessible thanks to advances in nanofabrication. In general, the proper design of nanophotonic structures can enable shaping, control, and enhancement of free-electron radiation, for any of the above-mentioned effects. Free-electron radiation in nanophotonics opens the way to promising applications, such as widely tunable integrated light sources from x-ray to THz frequencies, miniaturized particle accelerators, and highly sensitive high-energy particle detectors. Here, we review the emerging field of free-electron radiation in nanophotonics. We first present a general, unified framework to describe free-electron light–matter interaction in arbitrary nanophotonic systems. We then show how this framework sheds light on the physical underpinnings of many methods in the field used to control and enhance free-electron radiation. Namely, the framework points to the central role played by the photonic eigenmodes in controlling the output properties of free-electron radiation (e.g., frequency, directionality, and polarization). We then review experimental techniques to characterize free-electron radiation in scanning and transmission electron microscopes, which have emerged as the central platforms for experimental realization of the phenomena described in this review. We further discuss various experimental methods to control and extract spectral, angular, and polarization-resolved information on free-electron radiation. We conclude this review by outlining novel directions for this field, including ultrafast and quantum effects in free-electron radiation, tunable short-wavelength emitters in the ultraviolet and soft x-ray regimes, and free-electron radiation from topological states in photonic crystals. [ABSTRACT FROM AUTHOR]

The coherent crystalline domain size of a particle is well understood and investigable from the broadening of X-ray diffraction (XRD) peaks by Williamson–Hall (WH) method in connection with a strain, and it has a correlation with the strain, stress, energy density, defects/dislocations. The coherent domain size of binary semiconducting material particles is being interlinked with the applications like sensors, solar systems, photo-detectors, photocatalyst, etc. In this work, the frustrated microstructure of PbS elucidated the perspective of different models of the WH method. Frustrated microstructural PbS nanomaterial was prepared, confirmed and rendered its microstructural analysis from the XRD data and scanning electron microscope. Eight various approaches as the variant models of the Williamson–Hall plotting methods have been tested. It includes the models like Balzar approach, UDM, USDM, UDEDM, mWHP model, Ehkl/E0 ratio model, direct fitting of simplified WH model with introducing new approach and the modified Kibasomba-WH model, which uses linearization of Scherrer equation with the WH method. This study lightens the USDM and UDEDM sizes in an account of a Zener constant. The other non-WH methods like the Scherrer formula method, modified Scherrer method, stress–strain methods and Halder–Wagner method are also included for comparison and to see their status in a cluster of frustrated structures. The sizes in connection with strain, stress, energy density, dislocation and stacking fault have also been investigated for the frustrated PbS nanomaterial. [ABSTRACT FROM AUTHOR]

The paper aims to investigate the influence of silver addition on the microstructure of CuNi2Si1 alloys. The investigated copper alloy was cast and then supersaturated, plastically deformed on the Gleeble 3800 simulator and finally aged. Structural changes were examined using optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Orientation mapping was completed with FEI Quanta 3D field emission gun scanning electron microscope (SEM) equipped with TSL electron backscattered diffraction (EBSD) system. The effect of structural and microstructural changes on hardness and conductivity was also investigated. Based on the mechanical tests it was found that the mechanical properties and conductivity are improved due to heat and plastic treatment. It was also found that the precipitation hardening raises the hardness to the level of 40% whilst an increase in conductivity by 20% is observed. [ABSTRACT FROM AUTHOR]

Different collagen barrier membranes come in various sources and crosslinking that may affect barrier function and tissue integration. This study investigated barrier function and tissue integration of the three different collagen membranes (Jason®: porcine pericardium, GENOSS: bovine tendon, and BioMend® Extend: cross-linked bovine tendon) with human gingival fibroblasts. The barrier function and tissue integration properties were determined under confocal microscopy. Morphological characteristics were observed using scanning electron microscopy. Our results showed that all collagen membranes allowed a small number of cells to migrate, and the difference in barrier function ability was not significant. The cross-linked characteristics did not improve barrier ability. The native collagen membrane surfaces allowed evenly scattered proliferation of HGF, while the cross-linked collagen membrane induced patchy proliferation. Statistically significant differences in cell proliferation were found between Jason and BioMend Extend membranes (p = 0.04). Scanning electron microscope showed a compact membrane surface at the top, while the bottom surfaces displayed interwoven collagen fibers, which were denser in the crosslinked collagen membranes. Within the limitations of this study, collagen membranes of different origins and physical properties can adequately prevent the invasion of unwanted cells. Native collagen membranes may provide a better surface for gingival cell attachment and proliferation. [ABSTRACT FROM AUTHOR]

Bone is a heterogeneous, hierarchical biocomposite material made of an organic matrix filled with a mineral component, which plays an important role in bone strength. Although the effect of the mineral/matrix ratio on the mechanical properties of bone during aging has been intensively investigated, the relationship between the mechanical properties and the chemical composition of bone with age requires additional research in juvenile individuals. In this study, bone coupons from bovine and ovine animal species were machined from cortical areas of long bones to quantify whether the variation in mechanical properties at different stages of development is related to the change in the composition of bone tissue. An energy-dispersive X-ray detector (EDX) attached to a scanning electron microscope (SEM) was used to perform a compositional analysis of the tissue. In addition, nanoindentation analyses were carried out to address how the elastic modulus changed with age. Nonparametric statistical analyses found significant differences (p < 0.05) in Ca content and elastic modulus between species, but no differences were found within each species with development. A multiple linear regression model found that the elastic modulus was significantly related to the decrease in P and C in the samples, to the animal species (larger in bovine), and development, although not linearly. This model also found an interaction between Ca and development that could explain the lack of significance of the relationship between the elastic modulus and development in the univariate models. [ABSTRACT FROM AUTHOR]

In this study, microstructural evolution and its effects on mechanical properties across the thickness of a 120 mm Ni-Cr-Mo industrial ultra-heavy steel plate were quantitatively investigated by means of optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM) and electron back-scatter diffraction (EBSD). The results show that the martensite fraction is 65% at 10 mm and disappears at 40 mm, while granular bainite appears at 35 mm and climbs up to as high as 32% at 60 mm, with M-A constituents significantly coarsened. The strength drops with the gradual coarsening of the laths as well as decreased martensite fraction from the surface to the centre. The toughness is mainly affected by the block size and the morphology and quantity of M-A constituents. This study established a multivariate function between the microstructure and toughness (50% fibre area transition temperature, FATT50) with careful consideration of the influence of effective grain size (EGS) and M-A constituent size distribution. [ABSTRACT FROM AUTHOR]

In this article, Ni and Ni-BN-TiC layers were constructed using laser cladding technique (LCT). The microstructure, phase structure, microhardness, elastic modulus, thermal stability, and corrosion behaviors of Ni-BN-TiC layers were investigated using scanning electron microscope (SEM), X-ray diffractometer (XRD), nanoindentation, differential scanning calorimetry (DSC), and electrochemical workstation. The results indicated that Ni-BN-TiC layers possessed a fine and compact microstructure. The exothermic peak of the Ni-BN-TiC layer appeared at 461°C, indicating the highest thermal stability. The mechanical properties of Ni-BN-TiC layer improved with the addition of BN and TiC particles, having an average microhardness of 19.6 GPa, and average elastic modulus of 194.2 GPa. In addition, the corrosion current densities of 45 steel, Ni and Ni-BN-TiC layers were 4.808 μA/cm2, 3.917 μA/cm2, and 2.014 μA/cm2, respectively. The corrosion potentials and corrosion current densities results showed the outstanding corrosion resistance of Ni-BN-TiC layers. [ABSTRACT FROM AUTHOR]

Metal‐organic‐frameworks (MOFs), which are porous organic/inorganic materials and can be used for various applications in battery research, have grasped interest in the domains of energy storage and conversion systems because of highly tunable morphology, open topological structure, extremely redox active and large surface area. The battery type electrodes were synthesized through a hydrothermal approach which is followed by calcination process. Initially, X‐ray diffraction and scanning electron microscope characterizations were performed to study the MOFs structural and surface topologies. Later on, electrochemical characterizations (cyclic voltammetry, galvanostatic charge‐discharge and electrochemical impedance spectroscopy) were executed. Three electrode assembly were accomplished to test the electrochemical performance of Li MOF, Cu MOF and LiCu MOF in which the LiCu MOF electrode has obtained at 3 mV/s its highest specific capacity of 484.4 C/g. After studying the experimental process, the charge storage mechanism was further scrutinized by using multiple theoretical approaches, confirming the behavior of the synthesized materials. To explore further the application of LiCu MOF, a hybrid device was fabricated with activated carbon which results in high energy of 36.1 Wh/kg and power of 5100 W/kg. The obtained LiCu MOF material is a viable option for both batteries and hybrid supercapacitors electrodes due to its suitable electrochemical properties. [ABSTRACT FROM AUTHOR]

To create a (POT–CSA/ZnO) nanocomposite, a chemical oxidative polymerization of O-toluidine was carried out in the presence of nano ZnO. This step took place throughout the synthesis. In the attendance of hydro chloric acid (HCl) and ammonium persulfate (APS) as an oxidant and camphor solfunic acid (CSA) as a dopant, polymerization can be accomplished by using a monomer mixture with an equal molar ratio. Scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), and UV–Vis spectroscopy were utilized in the procedure of characterizing the material. The results displayed that the polymer film revealed both excitonic transition π – π and to π − π * transition. The semiconducting character of the composite can be confirmed by its electrical conductivity. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the preparation of Li-doped ZnO nanostructures through combustion and report on their structural, morphological, optical, and electrocatalysis properties. X-ray diffraction analyses show that the samples have a structure crystallized into the usual hexagonal wurtzite ZnO structure according to the P63mc space group. The scanning electron microscope images conceal all samples' nanosphere bundles and aggregates. The reflectance spectra analysis showed that the direct bandgap values varied from 3.273 eV (for pure ZnO, i.e., ZnL1) to 3.256 eV (for high Li-doped ZnO). The measured capacitance concerning frequency has estimated the variation of dielectric constant, dielectric loss, and AC conductivity against AC electric field frequency. The dielectric constant variations and AC conductivity are analyzed and discussed by well-known models such as Koop's phenomenological theory and Jonscher's law. The Raman spectra have been recorded and examined for the prepared samples. Rhodamine B was electro-catalytically degraded in all prepared samples, with the fastest time for ZnL5 being 3 min. [ABSTRACT FROM AUTHOR]

Bacterial infections are a serious threat to human health, and the rapid emergence of bacterial resistance caused by the abuse of antibiotics exacerbates the seriousness of this problem. Effectively utilizing natural products to construct new antimicrobial strategies is regarded as a promising way to suppress the rapid development of bacterial resistance. In this paper, we fabricated a new type of natural antibacterial patch by using a natural active substance (allicin) as an antibacterial agent and the porous structure of the white pulp of pomelo peel as a scaffold. The antibacterial activity and mechanisms were systematically investigated by using various technologies, including the bacteriostatic circle, plate counting, fluorescence staining, and a scanning electron microscope. Both gram-positive and negative bacteria can be effectively killed by this patch. Moreover, this natural antibacterial patch also showed significant anti-skin infection activity. This study provides a green approach for constructing efficient antibacterial patches. [ABSTRACT FROM AUTHOR]

The influences of natural bamboo fibers (BFs) weight fraction on the microstructure, quasi-static and dynamic compressive responses of the epoxy resin matrix composites were investigated with the aid of scanning electron microscope, electronic universal testing machine and the modified Split Hopkinson pressure bar (SHPB) setup. The quasi-static compressive properties of the BFs/epoxy resin matrix composites suggested that the compressive strength were strongly improved with the addition of the natural BFs, which was attributed to the excellent strengthening effect. When the BFs content increased up to 15 wt.%, the compression ratio of the BFs/epoxy resin matrix composites showed 11% reduction than that of the unmodified epoxy resin. Moreover, the stress and strain were linear at the initial part but nonlinear when stress exceeds a certain value. SHPB impact tests results indicated that, compared with the pristine epoxy resin, the natural BFs reinforced epoxy matrix composite with 15 wt.% BFs exhibited the highest dynamic compressive strength, compression modulus and the best strengthening effect. Epoxy resin matrix composites also showed an obvious effect rate effective under impact load. Similar to that in the quasi-static compressive test, the addition of natural BFs has a positive effect in improving the compressive strength of the epoxy matrix. [ABSTRACT FROM AUTHOR]

NdFe1−xCoxO3 samples are prepared by the sol–gel method. The X‐ray diffraction (XRD) results show that these samples conform to the orthogonal perovskite structure (Pbnm), and different doping amounts can cause the patterns to shift by XRD pattern. Through the Williamson–Hall analysis, the microstrain of the lattice between different doping amounts was obtained, and the average crystal size was calculated. The element content of each sample was obtained by scanning electron microscope and energy‐dispersive X‐ray analysis. Mössbauer spectra show that different doping levels change the surrounding environment of iron, and the magnetic properties of the samples also change. [ABSTRACT FROM AUTHOR]

The present work aims to synthesize and designate 50% BaFe11.5Co0.5O19 /50% NBR nanocomposite with enhanced physical properties. First, the BaFe11.5Co0.5O19 hexaferrite was successfully synthesized by the citrate auto-combustion technique. Composite nanoparticles were synthesized by melt mixing technique in a Brabender Plasticorder. The structure and morphology of the samples were investigated using X-ray diffraction (XRD), Fourier transform infrared (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy (AFM), and scanning electron microscope (SEM). The average crystallite size is nearly 35 nm. The high values of Ms for BFCO can be clarified by Fe3+–O–Fe3+ super-exchange interaction in the present system. An investigation has found that substitution in M-type hexaferrite systems alters the valence states of Fe3+ ions to Fe3+ ions at the 2A sites (Ateia et al. in Appl Phys A 128: 884, 2022). This causes an enhancement of super-exchange interactions that improves the hyperfine field at 2b and 12 k sites. The switching field distribution was computed and reported. Tensile strength (T.S), Young's modulus (E), hardness (H) and Rheometric characteristics were enhanced after the addition of BFCO nanoparticles to NBR polymer. The obtained data from the present study revealed that the incorporation of 50% of BaFe11.5Co0.5O19 hexaferrite with 50% of NBR rubber enhanced the physico-mechanical and magnetic characteristics of the prepared composites. This indicates that hexaferrites achieve not only appropriate magnetic properties for the prepared composites, but also strengthen the rubber matrix. The originality of this investigation is clarified by emphasizing the magnetization of NBR and to accentuate the good mechanical properties of the investigated nanocomposites. [ABSTRACT FROM AUTHOR]

We have successfully deposited a thin film of rare earth oxide on a Si substrate. After morphological characterization via a scanning electron microscope and an atomic force microscope, the electrical properties of the Al/Dy2O3/Si MOS structure were investigated using the current–voltage I(V) and capacitance–voltage C(V) measurements, as well as a study in the dynamic regime (AC) via conductance–frequency σ(f) measurements at different temperatures. Based on the classical Schottky model, we were able to determine some physical parameters, namely, the ideality factor and the potential barrier height. The effect of resistance and interface states on the current–voltage characteristics is observable and results in a deviation from the ideality factor. Then, dielectric data have been acquired by means of impedance spectroscopy over a wide frequency and temperature range. These results show that understanding the temperature dependence of the electrical characteristics of this structure may be of great help in improving the quality of Dy2O3 developed on a Si substrate for the future of device technology. [ABSTRACT FROM AUTHOR]