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Bovine bone is an animal‐origin matrix rich in type I collagen (COL I) and it necessitates prior demineralization and makes COL I available. This study investigated the ossein–hydroxyapatite physicochemical properties evaluation as a result of processing and solubilization by acids and revealed the bone matrix demineralization and making COL I available. The tibia residue from bovine sources was processed, ground, and transformed into bone matrix powder. The bone matrix was solubilized in acetic acid followed by lactic acid. The bone matrix was evaluated as a result of processing and solubilization by acids: ossein and hydroxyapatite percentages by nitrogen and ash content, mineral content, particle size distribution, Fourier‐transformation infrared spectroscopy, x‐ray diffraction, and scanning electron microscope. For the obtained residual extracts, pH and mineral content were evaluated. The solubilization by acids affected the ossein–hydroxyapatite physicochemical properties, and the bone matrix solubilized by acetic and lactic acid showed the preservation of the ossein alongside the loss of hydroxyapatite. The processing and the solubilization by acids were revealed to be a alternative to bone matrix demineralization and enabling the accessibility of bone COL I. Practical Application: Bovine bone is an abundant type I collagen source, but processing maneuvers and demineralization effect present limitations due to the rigidity of the structural components. Exploring methodologies to process and demineralize will allow type I collagen to be obtained from the bone source, and direct and amplify the potentialities in the chemical and food industries. The research focused on bone sources and collagen availability holds paramount significance, and promotes repurposing agribusiness residues and development of protein–base products. [ABSTRACT FROM AUTHOR]

Northwest China is known for its Majiayao‐style Neolithic painted pottery which has received much praise for its high level of craftsmanship, yet its chain of production, in particular the step of raw material selection, is still poorly understood. To fill this lacuna, the present study explores the raw materials used in producing these wares from a geological and technological perspective. At its core stands the first geoarchaeological survey conducted around the eponymous site of Majiayao which collected 47 samples of raw materials suitable for ceramic production including clay, loess and rocks, which were all analysed macroscopically. A selection was analysed using thin‐section petrography, and a subset of the clay and loess samples were subjected to firing experiments. Additionally, three clay samples were analysed by scanning electron microscope with energy‐dispersive X‐ray spectrometer to understand their composition and behaviour in ceramic production. These were then compared to archaeological ceramics, thus providing insights into raw‐material availability and selection that will be of importance not only for research on Majiayao‐style pottery but also for later‐period ceramics produced in the area. This research shows how an archaeologically informed geological survey can contribute insights into human–environment interaction in early pottery production, especially the interplay between raw‐material availability, technological know‐how and potters' choices. [ABSTRACT FROM AUTHOR]

The tensile behavior of a flexible epoxy resin reinforced with knitted reinforcements from various fiber materials was comprehensively studied in the wale and course direction. By measuring dry yarns, temperature‐treated yarns, dry knitted fabrics and flexible composites, the effect of the fiber material and the knitted fabric on the tensile properties was analyzed. The interlock knit structure strongly affected the deformation behavior of the flexible composites which differed significantly from the dry knitted fabrics. The deformation behavior of the flexible composites was monitored using digital image correlation which revealed the formation of cracks and high local strain differences in the course direction for all fiber materials. This was linked to fiber‐matrix debonding by scanning electron microscope observations. In the wale direction, the deformation of the knitted structure under tensile load led to plastic deformation of the matrix material. Overall, with yarns from recycled thermoplastic fibers, a higher maximum stress and strain at break was achieved compared to bio‐based fibers. However, irreversible damage occurred for all fiber materials at similar strain values. Highlights: Tensile tests on yarns, knitted fabrics and flexible composites.Investigation of the effect of fiber material on mechanical properties.High local strain differences in composites due to knitted structure.Fiber‐matrix debonding in course direction.Plastic deformation of the matrix material in the wale direction. [ABSTRACT FROM AUTHOR]

As a thermal phase transition material, VO2 is famous for its phase transition performance. When the temperature is lower than the phase transition temperature, VO2 behaves as a semiconductor with high infrared transmittance. When the temperature exceeds the phase transition temperature, VO2 exhibits a metallic state and has a high refractive index for infrared. Regulation of phase transition temperature is key to the application of VO2. In this article, microwave hydrothermal is used to prepare VO2. H+ concentration, microwave power, annealing temperature, and annealing time are used as variable conditions to find the best preparation conditions. The preparation of samples is studied by X‐ray diffractometer, scanning electron microscope, and differential scanning calorimeter. After comparative research, the optimum preparation process of vanadium dioxide by microwave hydrothermal method is found. In addition, by varying the acidic conditions and microwave power during the preparation process, the phase transition temperature of VO2 can be regulated. [ABSTRACT FROM AUTHOR]

Post‐synthetic modification using acid (HNO3) and base (NaOH) are utilised to synthesize hierarchical micro‐mesoporous zeolites with different pore structure. To investigate structural change in materials, X‐ray diffraction (XRD), Scanning electron microscope (SEM), Inductive coupled plasma‐optical emission spectrometry (ICP‐OES), 29Si and 27Al MAS NMR, and N2 adsorption‐desorption isotherms techniques were employed. Acid base titration, and ammonia‐temperature programmed desorption (NH3‐TPD) was performed to evaluate acidic characteristics of materials. As revealed by characterisation, the structure was well preserved after the modification. Hierarchical materials along with parent materials have been evaluated in the toluene alkylation with benzyl alcohol producing mono‐benzylated toluene. All zeolite samples were proved to be catalytically active by their result in the alkylation reaction. Acid treated samples were compared with base treated and parent samples. The results indicate that, base modification significantly increases the mesoporous pore volume in all zeolite as compared to acid modification. Moreover, the highest benzyl alcohol conversion was found to be 98 % in the base modified Beta, with the highest mono‐benzylated toluene selectivity (69 %). Reaction optimization was also studied by altering reaction duration, temperature, and catalyst amount. The reaction products were analysed using Gas Chromatography (GC) and confirmed using Gas chromatography mass spectrometry (GC‐MS). [ABSTRACT FROM AUTHOR]

In recent times, significant progress is made in the development of solar‐blind deep‐ultraviolet (DUV) photodetectors (200–280 nm) due to their potential applications for military and civil purposes. In this study, the development of a novel solar‐blind DUV photodetector based on tantalum pentoxide (Ta2O5) nanoparticles (NPs) utilizing Surface Acoustic Wave (SAW) sensor integrated with Interface electronics is reported for the first time. The 3‐D Ta2O5 NPs surface morphology, crystallinity, and defect state level is discussed using various analytical techniques, including scanning electron microscope (SEM), X‐ray diffraction (XRD), and spectrophotometer. The developed 3‐D Ta2O5 NPs based photodetector exhibits high sensitivity to 254 nm DUV irradiation (5 µW cm−2), demonstrating excellent photoresponse characteristics. The performance parameters including highest sensitivity, fast response/recovery time are measured as 1621.1 ppm (mW cm−2)−1, 3.7s/19.8s, respectively. Subsequent analysis demonstrates the stability and repeatability of the photodetector, enabling its potential to real time corona discharge detection. With its inherent advantages, the current DUV photodetector utilizing Ta2O5 NPs exhibits great potential for future applications in DUV optoelectronics. [ABSTRACT FROM AUTHOR]

Performing in situ scanning electron microscope (SEM) tests is an interesting way to visualise strain heterogeneities under mechanical loading. An essential step before performing the tests is to define the acquisition conditions. The aim of this paper is to propose a classification of the acquisition conditions that are most important for the accuracy of strain measurements using digital image correlation (DIC) in in situ SEM tests. More than 200 image pairs were acquired using a field emission gun SEM. The influence of different acquisition conditions was investigated: acceleration voltage, probe current, working distance, magnification, number of integrated images, image resolution, integration and number of integrated images, scan speed, contrast, brightness and exposure time of the sample in a given area. The methodology implemented in this work is an interesting tool for detecting scan line shift, drift distortion, spatial distortion and rastering artefacts. It allows the optimization of SEM acquisition conditions for strain measurements. Finally, optimal acquisition conditions for in situ testing are proposed and used to perform a tensile test on pure copper. The main factors highlighted include the size of the subset used in the DIC, the beam stabilisation time before image acquisition and the size of the images, which play a significant role in the results. It is recommended to apply the methodology to each device to optimise the acquisition conditions. [ABSTRACT FROM AUTHOR]

To meet the lightweight production requirements of automobiles and achieve high strength, reinforced thermoplastic composite materials are gradually replacing metal materials. Injection molding is the preferred manufacturing method to enable the production of complex‐shaped parts, facilitate production, and reduce costs. In this study, carbon fiber (CF) was added to the commonly used resin‐reinforcing material, polyamide (nylon) PA6, to create a CF‐reinforced thermoplastic composite (polyamide 6 [PA6]/CF) that was welded using injection molding. This study not only investigates the impact of different welding conditions on shear strength but also discusses the sequence of welding. Achieving 85% of the shear strength of the PA6 base material under ideal circumstances. The CF distribution and reinforcement mechanism were analyzed by observing the connection interface and cross section using a polarizing microscope and a scanning electron microscope. When PA6/CF was used as the secondary molded body, the welding results were better. The addition of CF had a significant strengthening effect on the strength of the PA6 injection welding. Highlights: Carbon fiber‐reinforced thermoplastic composite materials were prepared, and welding with PA6 was achieved using the injection molding method.The optimal welding parameters were determined by varying the mold, injection speed, injection temperature, and order of injection. The maximum welding shear strength reached 85% of the base material shear strength.The positive effect of specific fiber distribution on welding strength was analyzed by observing the interface using a scanning electron microscope and a polarizing microscope.This study provides valuable insights into the optimization of welding processes for carbon fiber thermoplastic composite materials, offering possibilities for connecting dissimilar materials with poor compatibility. [ABSTRACT FROM AUTHOR]

In this study, we developed physically adsorbed multi‐layer coatings using poly‐l‐lysine or poly(diallyldimethylammonium chloride) and gold nanoparticles, which were functionalized with bovine serum albumin for the chiral separation in electrochromatography. The approach involves sequentially depositing positively charged polymers and negatively charged citrate‐stabilized gold nanoparticles. By repeating this modification cycle, we created two‐ and four‐layer coatings, which were sequentially functionalized with albumin forming three‐ and five‐layer coatings that were finally applied for the separation of enantiomers of dl‐tryptophan. The formed coatings exhibit stability across a pH range of 2–10 and feature a dense, uniform surface, as confirmed by scanning electron microscope images. The number of layers impacted nanoparticle deposition density, with five‐layer coatings being denser than three‐layer ones. Five‐layer coatings enable baseline separation of dl‐tryptophan enantiomers, whereas three‐layer coatings require the presence of albumin in the background electrolyte for separation. Therefore, increasing the number of layers and gold nanoparticles density enhances albumin active center concentration on capillary walls, improving the separation of dl‐tryptophan enantiomers. The five‐layer coatings can be easily fabricated and possess good repeatability of analytes migration time. [ABSTRACT FROM AUTHOR]

Pure and metal‐doped ZnO nanopowders with composition formula M0.04Zn0.96O (where M = Al, Mg, Sm, and Cu) are synthesized using the coprecipitation method. The structural characterization of synthesized powders is investigated using X‐ray diffraction and the results confirm the hexagonal wurtzite structure without any additional phases. The change in structural parameters of ZnO with dopants is estimated using X‐ray peak profile analysis. The structural characterization is further analyzed by Fourier‐transform infrared spectroscopy. The size and morphology of the synthesized powders are analyzed by a field‐emission scanning electron microscope, which also evidences the formation of uniform nanostructures with quasi‐spherical and hexagonal shapes. Moreover, the elemental composition of these metal‐doped nanotructures is determined by energy‐dispersive X‐ray measurements. UV–vis spectroscopy is used to determine the energy bandgap of ZnO nanopowders. A vibration sample magnetometer is employed to measure the samples' magnetic properties, and dopants are found to induce distinct magnetic behaviors in ZnO. The antimicrobial activity of the synthesized powders is measured using the well diffusion method. It is observed that the introduction of dopant metals leads to increased microbial activity. Among the doped ZnO variants, Al‐doped ZnO exhibits the highest level of microbial activity compared to pure ZnO and other samples. [ABSTRACT FROM AUTHOR]

Dried leaves are the outstanding origin of cellulosic plant matter, and it is securing reputation as a renewable resource. Dried leaves fiber is suggested to possess the capability to substitute synthetic fibers in polymer laminates as a reinforcing component. The novelty of the present study reveals the effect of dried leaves fiber, cobalt, nickel, and ferrous reinforcement on the physical, mechanical, and thermal characteristics of epoxy, vinyl‐ester, and polyester polymers using artificial neural network (ANN) technique. These composites were fabricated using ultrasonication bath‐assisted wet layup method under ambient condition. The outcomes of this research exhibit that the dried leaves‐cobalt fillers reinforced in all three polymers possess higher mechanical and thermal stability characteristics when compared with other samples. The reason may be assigned to producing novel hydroxyl functional groups and strong interfacial bonding of fillers within the matrix as observed from Fourier‐transform infrared (FTIR) spectra and scanning electron microscope (SEM) micrographs, respectively. Moreover, as observed from the thermogravimetric analysis, the dried leaves‐ferrous filler‐reinforced polymer hybrid composites provided higher thermal stability. Statistical analysis was performed using the one‐way ANOVA technique and found that outcomes were significant statistically under the confidence level of 95%. Hence, this investigation not only emphasize the significance of investigating new polymer composites but also highlight the benefits of engaging advanced modeling to forecast the material characteristics precisely. Highlights: Dried leaves and cobalt/nickel/ferrous are applied reinforcement to polymers.Composites fabricated using ultrasonication bath‐assisted wet layup technique.LM Algorithm‐based ANN selected for predicting the best composite.Higher mechanical and thermal stability with dried leaves‐cobalt filler.One‐way ANOVA proved statistically significant within the material properties. [ABSTRACT FROM AUTHOR]

To overcome the dependence of continuous carbon fiber reinforced thermoset composites (CCFRTCs) on molds during the curing, a thermoset continuous fiber prepreg filament and thermoplastic filament alternate printing method was proposed. CCFRTCs with thin thermoplastic shells were prepared based on the method, and the confinement of thermoplastic shells enabled the mold‐less curing of CCFRTCs. The influence of key curing process parameters on the flexural properties of the specimens was systematically investigated. The experimental results showed that the flexural properties of the prepared composites were correlated positively with the vacuum degree and showed a tendency of first increasing and then decreasing with the increasement of impregnation time and curing temperature. Through x‐ray computed tomography (CT) and scanning electron microscope (SEM) analysis, the effect of key curing process parameters on the flexural properties of the CCFRTCs was clarified. Under the guidance of suitable curing process parameters, the flexural strength and modulus of the composite reached 482.89 MPa and 35.11 GPa, which were significantly better than most existing 3D printed continuous carbon fiber reinforced polymer composites. Finally, complex components were prepared to verify the feasibility and versatility of the technique. Highlights: A CCFRTCs mold‐less curing method was proposed.The effect of key parameters on the properties of CCFRTCs was clarified.Both the advantages of thermoset and thermoplastic materials were obtained.Complex components with low porosity were prepared. [ABSTRACT FROM AUTHOR]

The present work involves the coating synthesis of nano‐hydroxyapatite/chitosan (nHA/CS) on a Mg‐2 wt% Zn scaffold with the pulse electrodeposition (PED) technique. In practice, to render coatings more corrosion‐resistant and biocompatibility in simulated body fluids, the impact of PED factors, such as mean current density (j), a duty cycle, and coating duration (t), was investigated. Further, Fourier transform infrared spectroscopy, scanning electron microscope, x‐ray diffraction, energy‐dispersion spectrometer, and water contact angle (WCA) were studied to characterize coatings. The corrosion resistance of coatings was investigated by impedance evaluations and potentiodynamic polarization. The results obtained from analyses revealed that the optimum conditions for synthesizing the nHA/CS coating were achieved when applying j = 20 mA/cm2, a duty cycle = 0.4, and a duration of 60 minutes. The coatings' microstructure and Ca/P ratio were influenced by PED factors, which included nano spherical‐shaped and 1.65. Furthermore, the corrosion rate was decreased from 19.603 to 1.492 mm yr−1 after being modified by optimum coating. Moreover, the high hydrophilic properties are assigned to this coating with a WCA of 29.9 compared to other coatings and the Mg scaffold. The biological properties of the optimum coating were assessed through in‐vitro experiments involving MG63 cells, which included the evaluations of cell adhesion and cytotoxicity. The results obtained from the corrosion and in‐vitro experiments indicate that the nanocomposite coating, upon optimization, holds potential as a scaffold for bone tissue engineering. Highlights: Using Mg‐2 wt% Zn scaffold as a substrate for nanocomposite coatings.Pulse electrodeposition method for the synthesis of nano‐hydroxyapatite/chitosan (nHA/CS) coatings.Pulse electrodeposition (PED) method to modify morphology, corrosion resistance, and biocompatibility.Optimum PED parameters: j = 20 mA/cm2, duty cycle = 0.4, and t = 60 min. [ABSTRACT FROM AUTHOR]

4D scanning transmission electron microscopy (4D‐STEM) is a powerful method for characterizing electron‐transparent samples with down to sub‐Ångstrom spatial resolution. 4D‐STEM can reveal local crystallinity, orientation, grain size, strain, and many more sample properties by rastering a convergent electron beam over a sample area and acquiring a transmission diffraction pattern (DP) at each scan position. These patterns are rich in information about the atomic structure of the probed volume, making this technique a potent tool to characterize even inhomogeneous samples. 4D‐STEM can also be used in scanning electron microscopes (SEMs) by placing an electron‐sensitive camera below the sample. 4D‐STEM‐in‐SEMs is ideally suited to characterize 2D materials and 2D‐like van der Waals heterostructures (vdWH) due to their inherent thickness of a few nanometers. The lower accelerating voltage of SEMs leads to strong scattering even from monolayers. The large field of view and down to sub‐nm spatial resolution of SEMs are ideal to map properties of the different constituents of 2D‐like vdWH by probing their combined sample volume. A unique 4D‐STEM‐in‐SEM system is applied to reveal the single crystallinity of MoS2 exfoliated with gold‐mediation as well as the crystal orientation and coverage of both components of a C60/MoS2 vdWH are determined. [ABSTRACT FROM AUTHOR]

A new series of Co(II), Zn(II), Ru(III), and Ag(I) complexes with the ligand (Z)‐N′‐(1‐(thiophen‐2‐yl)ethylidene)‐2‐(p‐tolylamino)acetohydrazide (H2L) has been prepared. FT‐IR, 1H‐NMR, electronic spectra, powder X‐ray, and thermal behavior were applied to elucidate the structural composition of new compounds. The electronic spectra proved that the Co(II), Zn(II), and Ru(III) complexes possess tetrahedral geometry, except the Ag(I) complex is a binuclear complex. The mass spectrum of the Zn(II) and Ag(I) chelates and the molecular ion peak observed at m/z values equivalent to the calculated molecular weight confirmed the proposed structure. Also, the SEM scanning electron microscope technique explored the spherical shape of all chelates, and the nanoscale was confirmed through TEM; the transmission electron microscope tool that provided the 7.0 nm was achieved in the case of Zn(II) chelate. Geometry optimization for all synthesized compounds was estimated by density functional theory (DFT) method using the Gaussian09 program. Biological screening as an antimicrobial and antitumor was studied. The Ru(III) complex revealed the greatest antibacterial efficiency, followed by the Co(II) complex. Co(II) complex revealed a greater affinity against fungi such as Candida albicans and Aspergillus niger. All chelate‐induced antitumor effects against the MCF‐7 cell line, especially Ag(I) complex (IC50 = 62.36 μg/mL), exhibited the greatest efficiency. The activity sequence follows the order doxorubicin (standard drugs) > Ag(I) > Zn(II) > ligand < Ru(III) > Co(III) chelates. The molecular docking was performed and validated to support the biological results. [ABSTRACT FROM AUTHOR]

In this study, we sought to synthesize chitosan nanoparticles (CS‐NPs) and characterize their morphology, efficacy in inhibiting bacterial attachment, and efficacy in eradicating bacteria established on implantable hardware. CS‐NPs possess desirable properties, including antibacterial properties in biofilm‐mediated infections. CS‐NPs were produced using ionic gelation and characterized via scanning electron microscope imaging. Staphylococcus aureus was incubated with CS‐NPs at various concentrations and compared to a 1% povidone‐iodine with 1% H2O2 control in 24‐well plates. Stainless steel bone screws were placed in six‐well plates and inoculated with S. aureus. After 24 h, the screws were transferred to one of three solutions (saline, 40 mg/mL CS‐NP, or 1% povidone‐iodine with 1% H2O2). Four screws from each group were vortexed in saline and plated. The remaining screw from each group was prepped and imaged to map the location of persistent bacteria. Synthesized CS‐NPs had a mean diameter of 0.39 ± 0.13 μm and circularity of 0.87 ± 0.05. The percent inhibition of bacterial attachment was 73% at 20 mg/mL, 73% at 30 mg/mL, 75% at 40 mg/mL, 79% at 50 mg/mL, and 78% at 60 mg/mL. When compared to saline, the 40 mg/mL CS‐NP solution reduced bacteria on the screws by 76%. No bacteria were retrieved from the 1% povidone‐iodine with 1% H2O2 group. This study demonstrated that CS‐NP solution effectively inhibited S. aureus bacterial attachment and was more effective than saline in eradicating bacteria from orthopedic hardware, suggesting that CS‐NPs have the potential for prevention and treatment of musculoskeletal infections as a component of an intraoperative surgical irrigation solution. [ABSTRACT FROM AUTHOR]