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This report (I) aims to investigate defect behavior during the growth of heavily phosphorus (P)-doped Czochralski silicon (HP-Cz-Si) crystals. The defects and P chemical states in as-grown crystals with a resistivity of 0.6 mΩ cm and the wafers annealed at around 600 °C were evaluated by transmission electron microscopy and hard x-ray electron spectroscopy (HAXPES). Micro-dislocation loops (MDLs) were observed in the bottom portion of the crystal, and larger stacking faults (SFs), including complex dislocation clusters, were observed in the middle portion. HAXPES revealed two different P states, P1 and P2. P1 was attributed to a substitutional P (Ps). The P2 present in as-grown crystals was found to be electrically active, while the newly formed P2 after annealing was electrically inactive, indicating that they are in different states. HAXPES evaluation of HP-Cz-Si after electron irradiation showed similar behavior to P2 after annealing, suggesting that P-vacancy (V) clusters are formed when the crystals are held at temperatures below 600 °C during crystal growth. Combining the experimental results with our theoretical analysis in the report (II) based on density functional theory calculations, we identified the following defect formation mechanisms. Interstitial P (Pi) atoms introduced at the melting point become supersaturated during cooling to 600 °C, and MDLs are generated by the aggregation of Si self-interstitials (Is) released through a position exchange from Pi to Ps. In crystal portions with a long residence time below 600 °C, supersaturated Ps transforms into P–V clusters, and Is generated simultaneously are absorbed by the MDLs, which grow into SFs containing dislocation clusters. [ABSTRACT FROM AUTHOR]

We present a combined experimental and theoretical investigation of the radiationless decay spectrum of an O 1s double core hole in liquid water. Our experiments were carried out using liquid-jet electron spectroscopy from cylindrical microjets of normal and deuterated water. The signal of the double-core-hole spectral fingerprints (hypersatellites) of liquid water is clearly identified, with an intensity ratio to Auger decay of singly charged O 1s of 0.0014(5). We observe a significant isotope effect between liquid H2O and D2O. For theoretical modeling, the Auger electron spectrum of the central water molecule in a water pentamer was calculated using an electronic-structure toolkit combined with molecular-dynamics simulations to capture the influence of molecular rearrangement within the ultrashort lifetime of the double core hole. We obtained the static and dynamic Auger spectra for H2O, (H2O)5, D2O, and (D2O)5, instantaneous Auger spectra at selected times after core-level ionization, and the symmetrized oxygen-hydrogen distance as a function of time after double core ionization for all four prototypical systems. We consider this observation of liquid-water double core holes as a new tool to study ultrafast nuclear dynamics. [ABSTRACT FROM AUTHOR]

This study investigated the dissociation after the Xe 4d Auger decay of weak-bonding XeF2 molecules by multielectron–ion coincidence spectroscopy using a magnetic bottle electron spectrometer. Fragmentations from the XeF22+ states were clarified in the Auger spectra coincident with individual ion species. It was observed that the two-hole population led by the Auger decay was not directly inherited during the fragmentation of XeF22+. Furthermore, the dissociations of XeF23+ states produced by the double Auger decay were investigated. [ABSTRACT FROM AUTHOR]

As the channel lengths of electronic devices are scaled down to the nanometer range, the conventional methods to evaluate charge-carrier mobility approach a technical limit that is imposed by interfering effects of the electrode and forcing field. In this study, we demonstrate that electron spectroscopy provides additional (yet hidden) information on unipolar charge transport, which is free from conventional problems. We demonstrate that the estimated effective diffusion current through the target sample allows the measurement that is precise enough (10−4 cm2/V s) to obtain the mobility of electrons μelectron and holes μhole in nanolength organic channels. Using this method, we show how μelectron and μhole are correlated with the local structural order of poly(3-hexylthiophene) at the nanoscale. This method enables in situ charge-resolved observations of μelectron and μhole by eliminating the need for electrode and forcing field and will help to expand our understanding of charge conduction in nanoscale materials. [ABSTRACT FROM AUTHOR]

The transition metal silicide coatings have excellent oxidation resistance. In the high-temperature oxidization environment, the "anomalous" diffusion phenomenon of the reverse concentration gradient occurs in the multilayer silicide coating structure, which has a significant impact on the coating degradation. This study is to explore the physical mechanism of "anomalous" diffusion phase transformation in the MoSi2–NbSi2 bilayer silicide coating on the Nb alloy substrate. Through vacuum annealing experiments, combined with micro-Raman spectroscopy and electron probe microanalysis measurements, the diffuisonal phase transformation of multilayer silicide coating in the oxygen-free environment at high temperatures was studied. By decoupling the oxidation and diffusion, the experiments indicate that high-temperature oxidation is not the dominant driving factor for the "anomalous" diffusion of atoms. The thermodynamic analysis reveals that the reduction in the nucleation barrier of the silicide-poor layer due to multicomponent solid solution and the non-uniform distribution of component chemical potential provide the driving force for the "anomalous" diffusion growth. Based on the diffusion kinetic modeling, the simulation of diffusion-controlled phase transformation in multilayer silicide coating was carried out, and the effect of tracer diffusion coefficients on the growth of the silicide-poor phase was analyzed. The research will have guiding significance for the recognition of failure mechanisms of silicide coating systems and performance improvement. [ABSTRACT FROM AUTHOR]

The dependence of electron work function, Φ , on the thickness of Ti layers was investigated by making use of the Kelvin method under ambient conditions. Layers were produced by vacuum phase deposition and were analyzed by x-ray photoelectron spectroscopy and transmission electron microscopy. A quantum size effect was revealed finding work function to increase as the layer thickness, z, decreased below 4 nm. The extent of increase, Δ Φ , was understood in terms of a simple particle-in-a-box model arriving at the function Δ Φ = ℏ 2 π 2 / 2 m e z 2 . This equation being free of any adjustable parameter, consisting only of the Planck constant and electron mass, seems to be a reasonable first approximation. [ABSTRACT FROM AUTHOR]

The current state of electron probe methods [including energy loss spectroscopy of inelastically scattered electrons (EELS)] is considered. The analysis concerning the issues of their application, challenges, and limitations is performed. Particular attention is paid to the fundamental limitations and the means to overcome those during electron probe methods' subsequent development for the study of composite nanostructured materials. It is emphasized that the emitted electron energy spectrum dispersion (or electron energy distribution function width) is one of the main factors limiting a further increase in EELS energy resolution, although the use of direct detection sensors and monochromators allows one to approach the physical limit of this method. Novel low-macroscopic-field electron emitters are synthesized and investigated. Their properties are analyzed and compared with previously obtained specimens. Both energy and temporal resolutions of an EEL system utilizing the suggested cathodes are estimated. The comparison of its characteristics with the corresponding parameters of classical facilities is performed. The obtained results indicate the possibility to achieving a significant growth in energy and temporal resolutions as well as a decrease in the detection threshold of chemical elements with trace concentrations while maintaining relatively high emission current density values. [ABSTRACT FROM AUTHOR]

ABSTRACT Quantitative analysis of electron spectroscopy data from techniques such as Auger electron spectroscopy (AES) and X‐ray photoelectron spectroscopy (XPS) typically requires the use of relative sensitivity factors (RSFs). Virtually, all routine XPS experiments attempt to turn peak intensities into elemental or chemical compositions using RSFs. The comparability and reproducibility of surface chemical analysis by electron spectroscopies therefore require the standardisation of RSFs and their use. RSFs may be determined either from theoretical calculations based on photo‐ionisation cross‐sections or empirically through direct measurement of homogeneous reference samples of known composition. The accurate use of sensitivity factors, even empirically determined RSFs, requires accounting for the effect of material differences on relative intensities, the so‐called ‘matrix effects’. ISO 18118:2024 is the most recently revised version of the ISO standard for the use and determination of empirical RSFs for quantitative analysis of homogeneous materials by AES and XPS. This article provides a summary of the new, updated standard and the methods described therein, noting in particular the revisions made since the previous edition, ISO 18118:2015. [ABSTRACT FROM AUTHOR]

The titanium scaffolds and surface-porous implants are manufactured by fast and cheap additive methods such as selective laser melting (SLM). The obtained irregularity and relative biological inertness of the titanium need proper surface modification. This research is aimed at forming bioactive multicomponent oxide coatings by micro-arc oxidation (MAO) at different process parameters on the selective laser-melted Ti13Zr13Nb alloy. The MAO process was carried out in a base solution containing 0.15 mol/L Ca and 0.1 mol/L GP, with different amounts of metasilicate added under two different applied voltages. Scanning electron microscopy, atomic force microscopy, X-ray electron diffraction spectroscopy, nanomechanical and nano scratch tests, water contact angle measurements, phosphate deposition observed in long-term immersion tests, and biological LDH and MTT assays were performed. The results showed that the coating microstructure, morphology, and properties were significantly dependent on process parameters. In particular, the metasilicate addition and its rising content in the electrolyte resulted in the higher development of the surface followed by better viability of osteoblasts at no necrosis, with no negative change in the other parameters, usually close to those obtained on silicon-free coatings. The obtained results prove that the addition of silicon to the electrolyte at the partial expense of calcium can be favorable for long-term titanium implants made by selective laser melting. [Display omitted] [ABSTRACT FROM AUTHOR]

Oil and gas resources are becoming increasingly difficult to extract owing to long-term exploitation. Therefore, hydraulic pressure technologies, such as fracturing proppants, are needed to stimulate production. In this study, the strength and corrosion resistance of quartz were increased by modifying quartz sand and preparing high-performance coated-sand-based oil-fracturing proppants. Although many resins play crucial roles in the process of preparing fracturing proppants, their performances differ considerably. Chemical structural compositions and microstructures were investigated through infrared spectroscopy and scanning electron microscopy. The modification mechanism of quartz sand and the bonding mechanism between quartz sand and different types of resin proppants were analyzed by systematically investigating the flexural strength, corrosion resistance of the proppants as a function of resin contents, and curing temperature. The results show that the performance of the coated proppants is superior to those of conventional quartz sand and ceramic proppants. The flexural strength of modified quartz sand improved by 5.3%. The best performance was obtained using an 8% polyimide resin film and a curing temperature of 180 °C, achieving a coated sand proppant with a breakage ratio of 2.89% under 55.2 MPa. [ABSTRACT FROM AUTHOR]

ABSTRACT The corrosion of 2198 aluminum–lithium alloy in a marine atmospheric environment was simulated using a wet–dry alternating experimental setup. Weight‐loss measurement methods, electrochemical impedance spectroscopy (EIS), scanning electron microscopy/energy‐dispersive spectroscopy (SEM/EDS), macroscopic morphology testing, three‐dimensional morphology testing, and X‐ray photoelectron spectroscopy (XPS) were used to study the wet–dry alternating corrosion behaviors and mechanisms of 2198 aluminum–lithium alloys under simulated marine atmospheric environment. The results indicate that corrosion weight loss increases with decreasing wet‐to‐dry ratios, accompanied by an increase in the corrosion rate. Various data suggest that the primary corrosion products are composed of Al2O3, AlO(OH), and AlCl3. The reduction in the wet‐to‐dry ratio leads to the enrichment of Cl⁻ within the corrosion products, extending the contact time between the substrate and the medium, thereby intensifying the hydrolysis of Al³⁺. This exacerbates the dissolution at pitting sites, which in turn erodes and breaks down the corrosion product film, accelerating the overall corrosion process. [ABSTRACT FROM AUTHOR]

Film-electrochemical electron paramagnetic resonance spectroscopy (FE-EPR) enables simultaneous electrochemical and spectroscopic characterisation of paramagnetic electron-transfer centres, including in soluble proteins. We now report a modified set-up FE-EPR with tuneable macroporous working electrodes and demonstrate the feasibility to investigate electron transfer in membrane proteins in their native membrane environment. [ABSTRACT FROM AUTHOR]

High‐temperature‐withstanding TiO2‐reinforced cyanate ester composites are developed by mechanical stirring, followed by curing at elevated temperatures. The uniform dispersion of the filler is confirmed using scanning electron microscopy and electron dispersive spectroscopy. All composites, up to a filler fraction of 30 vol%, exhibit a density of more than 90% while it reduces significantly after that. A high relative permittivity of 7.6 and a low loss tangent of 0.0112 are observed for the optimally filled 30 vol%. The addition of the filler further improves the temperature‐withstanding capability of the cyanate ester matrix. Moreover, a high thermal conductivity of 0.543 W mK−1, improved hardness of 24.88 HV, ultimate tensile strength of 11.68 MPa, and a low coefficient of thermal expansion of 36.44 ppm °C−1 are also shown by the optimally filled sample. A moisture absorption of 0.072 vol% observed for the optimal filled sample comes within the limit for microwave substrate applications. Thus, the developed composites are suitable candidates for high‐temperature microwave electronic applications. [ABSTRACT FROM AUTHOR]

N‐Heterocyclic olefins (NHOs), possessing highly polarizable and remarkably electron‐rich double bonds, have been effectively utilized as exceptional anchors for surface modifications. Herein, the adsorption, orientation, and electronic properties of NHOs on a metal surface are investigated. On Cu(111), the sterically low‐demanding IMe‐NHO is compared to its analogous IMe‐NHC counterpart. High‐resolution electron energy‐loss spectroscopy (HREELS) measurements show for both molecules a flat‐lying ring adsorption configuration. While the NHC adopts a dimer configuration including a Cu adatom, the NHO chemisorbs over a C–Cu bond perpendicular to the surface. This distinct difference leads for the IMe‐NHOs to have a higher thermal stability on the surface. Moreover, IMe‐NHOs introduce a higher net electron transfer to the surface compared to the IMe‐NHCs, which results in a stronger effect on the work function. These results highlight the role of NHOs in surface science as they extend the functionalization capabilities of NHCs into stronger electronic modification. [ABSTRACT FROM AUTHOR]

In this study, we examined dyeing behavior of tannic acid modified ultra high molecular weight polyethylene fabric. Whole study was conducted to see the effect of tannic acid on dope dyeing performance of the fabric. Tannic acid and its complex with sodium salt TA‐Na+ complex were used for pretreatment. After dope dyeing, the color strength of fabrics, color fastness, surface morphology, and fiber structure were characterized by k/s value, color difference, scanning electron microscopy (SEM), electron dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR), respectively. The effect of treatment conditions was also discussed. The results had shown better color strength and washing fastness were obtained after tannic acid treatment, especially after TA‐Na+ complex treatment. SEM observation indicated the tannic acid adhesion on fabric surface. Both EDS and FTIR results showed the enhancement of surface polarity. And the UHMWPE fabric treated with 1% (w/v) TA‐Na+ with pH ranging 4–5 for 6 h showed better color durability over time. Approach was suitable because of sustainable, green behavior of tannic acid and entire process had a low cost. [ABSTRACT FROM AUTHOR]

This study developed three composite slurries for coating recycled aggregate by incorporating polyacrylate emulsion, fly ash, and gypsum into a cement-based mixture. The filling and pozzolanic effects of fly ash help to improve microcracks in the recycled aggregates. The polyacrylate emulsion forms a strong bonding layer between the cement matrix and the aggregates, enhancing the interfacial bond strength. Based on relevant studies, the following mix designs were developed: Slurry 1 consists of pure cement paste; Slurry 2 contains 15% fly ash and 3% gypsum added to the cement paste; Slurry 3 adds 22% polyacrylate emulsion to the slurry. The study first compared the effects of the three composite slurries on the crushing value and water absorption of recycled aggregates, and then analyzed their impact on the mechanical properties, permeability, and drying shrinkage of concrete. Finally, the mechanisms behind the enhancement were investigated using the Vickers Hardness Test (HV), Mercury Intrusion Porosimetry (MIP), and scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS). The results showed that the polyacrylate emulsion composite slurry had the most significant improvement effect. For recycled aggregate AL, the crushing value decreased from 28.8% to 22.5% and the saturated surface–dry water absorption decreased from 15.1% to 13.8% after cement slurry modification. After coating with the composite slurry, the crushing value further dropped to 18.2% and the water absorption to 9.5%. Two aspects of the performance of recycled aggregates are enhanced with the polymer composite slurry: first, fly ash provides nucleation sites for CH, reducing the tendency for directional CH alignment. Second, the long chains of PAE (polyacrylic ester) encapsulate cementitious particles, effectively filling surface defects on the recycled aggregates, improving the bonding strength at the new-to-old interface, and significantly enhancing the performance of both recycled aggregates and recycled concrete. [ABSTRACT FROM AUTHOR]

Hydropyrochlore, ideally (H2O,□)2Nb2(O,OH)6(H2O), is a cubic mineral (space group Fd 3 m, a = 10.56–10.59 Å, Z = 8) belonging to the pyrochlore supergroup (general formula: A2–mB2X6–wY1–n). The K-rich variety of this species is unique to the Lueshe syenitic-carbonatitic deposit (D.R. Congo), where it occurs as the alteration product of primary (Ca,Na)2Nb2O6F pyrochlores. The structure of this mineral is made of a B2X6 (B = Nb, Ti; X = O, OH) framework that generates tunnels along the [110] direction, where the interstitial sites are partially occupied by water molecules and minor amounts of different cations. These features form the basis for the ion-exchange properties of hydropyrochlore, making it a promising candidate as a mineral sink for heavy metals (e.g., Tl+) dispersed in aqueous matrices, with interesting environmental implications. Tl+ incorporation was induced through imbibition experiments in a diluted Clerici solution using single crystals of hydropyrochlore from Lueshe (D.R. Congo); the modifications induced by Tl+ incorporation were then evaluated using single-crystal X-ray diffraction (SCXRD), electron microprobe analyses (EMPA), and Fourier transform infrared (FTIR) spectroscopy. After Tl+ imbibition, a dramatic increase of the A-site electron density (n.e– from ~4 to ~60) confirms the entry of a substantial amount of Tl+ at this site (up to about 70%), leading to a lengthening of the A-X distances and the consequent expansion of the unit cell. A decrease of the site scattering at the Y′ site (from ~9 to ~4 e–) also occurs, suggesting a loss of aqueous species. Although the predominance of neutral H2O molecules at the interstitial sites of hydropyrochlore from Lueshe is widely accepted by the mineralogical community, our crystal-chemical and FTIR data provide evidence that the dominant species might be the hydronium ion, with significant implications on the nomenclature of the pyrochlore supergroup. Understanding the crystallographic aspects of hydropyrochlore as a potential waste form for monovalent thallium immobilization not only addresses a pressing environmental concern but also contributes to the broader field of waste management. [ABSTRACT FROM AUTHOR]

Gallstone formation is one of the most severe human diseases, with regional differences in gallstone composition worldwide. The formation of gallstones inside the gallbladder is a complex process and is still under debate despite advances in instrumentation. This study was an in‐depth analysis of the chemical, structural, and elemental composition of cholesterol and pigment‐type gallstones using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM–EDS). Thermal gravimetric and differential scanning calorimetry (TG‐DSC) analysis was also carried out on gallstones to predict their thermal behavior. FTIR spectroscopy was employed to distinguish the cholesterol and pigment gallstones. Using SEM, we performed the morphological studies of gallstone and EDS were carried out to analyze elemental distribution within the gallstones. Elemental imaging and mapping of the major and minor elements within the cholesterol and black pigment gallstones were carried out, revealing the stone's heterogeneous nature. The level of heavy and toxic elements was found to be higher in pigment stones than in cholesterol gallstones. The results obtained from TG‐DSC are well correlated and supported by the results from FTIR spectroscopy. [ABSTRACT FROM AUTHOR]

This study presents the development of a synthesis route for sodium aluminosilicate hydrate (N–A–S–H) gels with various Si/Al ratios carried out at ambient temperature. The synthesis is based on a simple "sol–gel" method, where commercial reactants are used to provide highly reactive Si and Al sources. Comprehensive characterization, including scanning electron microscope‐energy‐dispersive spectroscopy (SEM‐EDS), gas pycnometry, inductively coupled plasma (ICP), X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and magic angle spinning (MAS) nuclear magnetic resonance (NMR) (27Al, 23Na, 29Si, and 1H), is employed to verify the morphology, density, chemical composition, long‐range order, and local structure of the gels. Our results show that the synthesized gels are pure, amorphous, and homogeneous with Si/Al final ratio ranging from 1.22 to 2.23. Structural analysis of the gels indicates the synthesis of compounds with high degree of geopolymerization, which are representative of N–A–S–H gel formed in sodium‐based geopolymers. [ABSTRACT FROM AUTHOR]

Background: Natural pigments are becoming more significant because of the rising cost of raw materials, pollution, and the complexity of synthetic pigments. Compared to synthetic pigments, natural pigments exhibit antimicrobial properties and is less allergic. Pigments from microbial sources could easily be obtained in an inexpensive culture media, produced in high yields, and microbes are capable of producing different colored pigments. Searching for new sources for natural pigments to replace synthetic ones in food applications has become an urgent necessity, but the instability of these compounds is sometimes considered one of the obstacles that reduce their application. Encapsulation provides an ideal solution for natural dye protection through a controlled release strategy. Thus, this study aims at isolation of several soil fungi and subsequent screening their pigment production ability. The chosen pigment-producing fungal strain underwent full identification. The produced pigment was extracted with ethyl acetate and estimated spectrophotometrically. As there is a necessity to obtain a high pigment yield for efficient industrial application, the best production medium was tested, optimum conditions for maximum dye production were also investigated through the response surface methodology, and gamma irradiation was also employed to enhance the fungal productivity. Encapsulation of the produced pigment into chitosan microsphere was tested. The pigment release under different pH conditions was also investigated. Results: A new strain, Fusarium verticillioides AUMC 15934 was chosen and identified for a violet pigment production process. Out of four different media studied, the tested strain grew well on potato dextrose broth medium. Optimum conditions are initial medium pH 8, 25 °C-incubation temperature, and for 15-day incubation period under shaking state. Moreover, a 400 Gy irradiation dose enhanced the pigment production. Chitosan microsphere loaded by the pigment was successfully prepared and characterized by infrared spectroscopy and scanning electron microscopy. Conclusion: This irradiated Fusarium strain provides a more economically favorable source for production of a natural violet dye with an optimum productivity, enhanced yield, and improved properties (such as, enhanced stability, controlled release, and bioaccessibility) by encapsulation with chitosan for efficient application in food industry. [ABSTRACT FROM AUTHOR]

The quantification of the lowest unoccupied molecular orbital level (LUMO) for molecular semiconductors is of great importance, because it determines the charge transport process and hence the performances of diverse electronic devices. Unfortunately, there is always lack of a convenient technique to determine the intrinsic LUMO. This work provides a reliable electrical spectroscopy by employing an easy-operating hot electron transistor, to make an accurate measurement. By taking advantage of a novel method, named the first derivative-assisted linear fitting method, the determination of the intrinsic LUMO becomes more scientific. Here, four kinds of molecular semiconductors are selected as the research objects and the values can be precisely decided even with a quite small difference in LUMO, which demonstrate the universality and the accuracy of our method. As expected, all the measured values are highly repeatable and it further confirms that we have provided a practical technique for the LUMO detection. [ABSTRACT FROM AUTHOR]

In this study, a novel colorimetric method is developed for the detection of arsenic and mercury ions, utilizing the surface plasmon resonance (SPR) properties of AuNPs (AuNPs=gold nanoparticles) functionalized with APT (APT=5-(3-aminophenyl) tetrazole). Theoretical calculations confirm the findings from UV–Visible spectroscopy and transmission electron microscopy analyses, indicating that APT is electrostatically bound to the surfaces of the AuNPs. The introduction of As3+ and Hg2+ ions triggers a coordination reaction with APT, resulting in a reduced interparticle distance among the AuNPs. This change leads to a visible color shift of the solution from wine red to bluish-gray. The detection limits for As3+ and Hg2+ are determined to be 0.6 and 0.24 μ g⋅mL−1, respectively, distinguishable to the naked eye. A robust linear correlation is observed between the absorbance ratios and the ion concentrations, with correlation coefficients (R2) of 0.990 for As3+ and 0.998 for Hg2+. These findings demonstrate that AuNPs functionalized with APT are effective for the quantitative analysis of arsenic and mercury ions. The sensor exhibits high selectivity and excellent resistance to interference, indicating its potential applicability for monitoring As3+ and Hg2+ in tap water and cosmetic products. [ABSTRACT FROM AUTHOR]

Steel slag-based glass ceramic for thermal energy storage was first fabricated by quenching method, and then their high temperature corrosion behavior in the eutectic carbonates and related mechanism have been investigated using X-ray diffraction，Raman spectroscopy and scanning electron microscope techniques. The results show that holding time has a significant influence on the corrosion layer thickness at 800oC. As the holding time was extended, the thickness of the corrosion layer with obvious cracks tended to increase. Further EDS analyses disclosed that the divided corrosive layers along the extended directions of the cracks should be similar in both the compositions and microstructure. Based on these observations, the possible corrosion mechanism was discussed after defining phase structure of nonstoichiometric (Fe 0.35 Al 0.20 Mg 0.44) Ca 0.96 (Fe 0.08 Si 0.70 Al 0.20) 2 O 6.12 as a combined system of CaMgSi 2 O 6 (Di)-CaFe3+AlSiO 6 (Es)-CaAl 2 Si 2 O 8 (An). Oxygen offered by the molten carbonates salt is regarded to play a critical role in the corrosion process. In an atmosphere rich in oxygen, both Na+ and K+ ions diffused into the diopside can replace Ca2+ and Mg2+, etc. resulting in polyhedral structural reorganization for electrical neutrality. On the other hand, the bonding stability of the cation-oxygen bonds in diopside was proved to be weaker than that in single oxides. These two aspects contribute to the continuous dissolution of Ca2+ and Mg2+, etc. in the molten carbonates salt. [ABSTRACT FROM AUTHOR]

Carbon black has been successfully converted into silicon carbide by reacting it with SiO vapor at 1500 °C under Ar gas environment. The influence of reaction temperature, duration and Ar gas flow rate on the final product was examined. The structural and microstructural property of synthesized SiC was characterized using X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM). Micrographs of synthesized SiC showed that the final product was an agglomeration of SiC nano-powder of 50–500 nm size and nano-whiskers/fibres having a diameter of 50–500 nm and lengths in 0.1–10 μm depending on Ar gas flow rate. The higher conversion of C into SiC was observed at 1500 °C with Ar gas flow rate ∼250 ml/min. [ABSTRACT FROM AUTHOR]

Active coatings have been extensively studied due to their ability to contain active substances that can promote ab/adsorption and/or catalysis of compounds of interest. In this work, solution blow spraying (SBSp), which is a modification of the solution blow spinning (SBS), was used to produce active coatings via a multistep process: The first stage consisted in applying a cross‐linkable polymer layer (epoxy) to a metallic substrate, followed by heating at 50°C to promote partial cross‐linking; in the second step, particle suspensions containing zinc oxide (ZnO) and/or bentonite/ZnO were sprayed over the resin layer so that particles adhered to the surface rather than embedded in, what would reduce surface activity. Primarily, rheology of the suspensions and resin cure were characterized by rheometry and differential scanning calorimetry (DSC), respectively. Infrared spectroscopy and scanning electron microscopy of the ZnO synthesized by the Pechini method was performed. Coatings were analyzed by optical microscopy (OM), scanning electron microscopy (SEM), and x‐ray diffraction (XRD). Based on the suspension studies, the optimized particle concentration was found to be 10 wt% in water. Thermal analysis of resin showed the ideal time and temperature of 16 min or 33 min at 50°C. Using these variables, active coatings with ZnO and bentonite/ZnO particles exposed to the surface were successful produced by SBSp. [ABSTRACT FROM AUTHOR]

Instrumentation developments in electron energy-loss spectroscopy in the scanning transmission electron microscope one decade ago paved the way for combining milli-electron volt energy resolution in spectroscopy with Ångström-sized electron probes, unlocking unexplored realms for solid state physics at the nanometer scale. The fundamental understanding of the scattering processes involved has made it possible to separate atomically localized signals, providing insight into vibrations at the atomic scale. In this Letter, we outline the experimental, conceptual, and theoretical advances in this field and also make comparisons with tip-based optical techniques before discussing future perspectives of this exciting method. Optimization of dark-field signal collection will play a fundamental role in making this technique more widely applicable to a range of material problems. The benefits of adding momentum-resolution will also be discussed, and a powerful acquisition scheme will be proposed. [ABSTRACT FROM AUTHOR]

In this work, steam-exfoliated graphitic carbon nitride was used as a promising basis for the development of photoactive materials for processes induced by visible light. Nanocrystalline cobalt(II,III) oxide, obtained by the solution combustion method followed by heat treatment of the reaction products, was used as a cocatalyst. Nanocomposite materials were prepared by joint ultrasonic treatment of graphite-like carbon nitride and cobalt(II,III) oxide in ethanol. The prepared series of samples with different weight fractions of the oxide (5–10 wt %) was studied by powder X-ray diffractometry, scanning electron microscopy, low-temperature nitrogen adsorption–desorption, and diffuse reflectance electron spectroscopy. The photocatalytic activity of the samples was evaluated in the oxidation of tetracycline hydrochloride. It was found that the rate constant of the photocatalytic reaction reached its maximum value with composites containing 7 wt % Co3O4 (k = 0.0104 min–1). The photovoltaic response studies demonstrated that the presence of cobalt oxide in the samples can significantly decrease the rate of charge carrier recombination to increase the generated current by a factor of 1.2. [ABSTRACT FROM AUTHOR]

Optical fiber X-ray sensors have the potential to realize real-time dose monitoring of precision radiotherapy. However, an over-response phenomenon can occur when using an optical fiber sensor (OFXS) filled with inorganic scintillator (Gd2O2S:Tb) to measure the off-axis ratio (OAR) curve. The aim of this paper is to study the mechanism responsible for the over-response. Due to the complex particle distribution present in water phantoms, the Monte Carlo-based code GEANT4 was used to model the response of the scintillator. The energy response of the scintillator to photons and electrons was initially simulated, which subsequently allowed the OAR curve to be simulated and the results were compared with experiment. To analyze the energy distribution of particles in different positions, electron spectroscopy was simulated together with the photon spectrum at the position from the central axis to a distance of 14.5 cm away from the center. Finally, three metal (Al, Cu, Sn) caps were made for the OFXS to prevent the low-energy photons penetrating the OFXS, and the OARs measurements were repeated. The results show that the scintillator exhibits higher sensitivity to photons with energy below 0.5 MeV, while for electrons, the scintillator has a higher sensitivity to high-energy electrons. Simulations for electron spectroscopy and the photon spectrum show that there are many low-energy photons with relatively few low-energy electrons. The OARs measured using the OFXS with metal caps show that the over-response can be mitigated using a high-Z metal cap. The measurements demonstrate that the OAR cure measured using an OFXS fitted with a Sn cap exhibits the closest response to that measured using an IC. [ABSTRACT FROM AUTHOR]

Co/B co‐doped ZnO nanoparticles, denoted as Zn0.95‐xBxCo0.05O, are synthesized using the sol–gel method to explore the effects of the defects on optical properties. The stoichiometry is adjusted by varying the doping levels (x = 0.00, 0.01, 0.02, 0.03, 0.04, and 0.05). X‐ray diffraction is employed to analyze the structural characteristics of all Co/B co‐doped ZnO nanoparticles, confirming the presence of a hexagonal Wurtzite structure by assessing the c/a ratios. To investigate structural defects, photoluminescence properties are measured using the Fluorescence Spectrophotometer, revealing violet, blue, green, and red emissions. With the doped of boron (B), a shift from green emission to blue emission occurs, indicating a transformation of singly charged oxygen vacancies (VO+) to VZn vacancies. Fourier Transform Infrared (FTIR) spectra (4000–400 cm−1) are acquired using the Perkin Elmer Spectrum Two FTIR‐ATR spectrophotometer. The surface morphology, crystallite size, and nanoparticle shapes are characterized through Transmission Electron Microscope (TEM) analysis. Elemental compositions are determined using Electron Dispersive Spectroscopy (EDAX). The Shimadzu 2600 UV‐Spectrophotometer is used to examine optical characteristics. The samples' energy band gaps are calculated, and the impact of dopant elements on these optical characteristics is examined. Five different models are used to compute the refractive index. [ABSTRACT FROM AUTHOR]

Perovskite solar cells are considered to be one of the most promising solar cell designs in terms of photovoltaic efficiency. However, their practical deployment is strongly affected by their short lifetimes, mostly caused by environmental conditions and UV degradation. In this contribution, we present a metasurface made of silver nanoparticles used as a UV filter on a perovskite solar cell. The UV-blocking layer was fabricated and morphologically and compositionally analyzed. Its optical response, in terms of optical transmission, was also experimentally measured. These results were compared with simulations made through the use of a well-proven computational electromagnetism model. After analyzing the discrepancies between the experimental and simulated results and checking those obtained from electron beam microscopy and electron dispersion spectroscopy, we could see that a residue from fabrication, sodium citrate, strongly modified the optical response of the system, generating a redshift of about 50 nm. Then, we proposed and simulated the optical behavior of core–shell nanoparticles made of silver and silica. The calculated spectral absorption at the active perovskite layer shows how the appropriate selection of the geometrical parameters of these core–shell particles is able to tune the absorption at the active layer by removing a significant portion of the UV band and reducing the absorption of the active layer from 90% to 5% at a resonance wavelength of 403 nm. [ABSTRACT FROM AUTHOR]

This study aimed to assess the antibiofilm effects of dentin desensitizers using a modified Robbins device flow cell system. The test desensitizers were Saforide, Caredyne Shield, and Clinpro White Varnish. Standardized dentin specimens were prepared from human single-rooted premolars, treated with one of the materials, and mounted on the modified Robbins device flow cell system. Streptococcus mutans biofilms were developed for 24 h at 37 °C under anaerobic conditions. Scanning electron microscopy, fluorescence confocal laser scanning microscopy, viable and total cell counts, acid production, and gene expression analyses were performed. A wavelength-dispersive X-ray spectroscopy electron probe microanalyzer was used to analyze the ion incorporations. Clinpro White Varnish showed the greatest inhibition, suggesting its suppression of bacterial adherence and transcription of genes related to biofilm formation. Saforide reduced only the number of viable bacteria, but other results showed no significant difference. The antibiofilm effects of Caredyne Shield were limited. The uptake of ions released from a material into dentin varies depending on the element. Clinpro White Varnish is effective for the short-term treatment of tooth sensitivity due to dentin demineralization. It prioritizes remineralization by supplying calcium and fluoride ions while resisting biofilm formation. [ABSTRACT FROM AUTHOR]

Hydrogen boride (HB) sheets are emerging as a promising two-dimensional (2D) boron material, with potential applications as unique electrodes, substrates, and hydrogen storage materials. The 2D layered structure of HB was successfully synthesized using an ion-exchange method. The chemical bonding and structure of the HB sheets were investigated using Fourier Transform Infrared (FT–IR) spectroscopy and Transmission Electron Microscopy (TEM), respectively. X-ray photoelectron spectroscopy (XPS) was employed to study the chemical states and transformation of the components before and after atomic hydrogen adsorption, thereby elucidating the atomic hydrogen adsorption process on HB sheets. Our results indicate that, upon atomic hydrogen adsorption onto the HB sheets, the B-H-B bonds were broken and converted into B-H bonds. This research highlights and demonstrates the changes in chemical states and component transformations of the boron element on the HB sheets' surface before and after atomic hydrogen adsorption, thus providing a clearer understanding of the unique bonding and structural characteristics of the HB sheets. [ABSTRACT FROM AUTHOR]

This study utilized a bobbin tool to friction stir weld aluminum 6082 workpieces under two sets of process parameters: a tool rotation speed of 280 rev/min with a weld velocity of 280 mm/min (280/280) and a tool rotation speed of 450 rev/min with a weld velocity of 450 mm/min (450/450). The weld microstructures were characterized through optical microscopy utilizing polarized light and through transmission electron microscopy (TEM) and scanning electron microscopy (SEM) coupled with chemical analysis by energy dispersive spectroscopy and electron back scatter diffraction. The microstructural studies were supplemented by hardness measurements (Vickers) performed on the same sections as the metallographic examinations. The produced weldments were free from cracks and any discontinuities. Fine, equiaxed grains that were several microns in size characterized the stir zones (SZs), and the advancing (AS) and retreating (RS) sides revealed distinct microstructural features. On the AS, the transition from the thermo-mechanically affected zone to the SZ was well defined and sharp, but on the RS, the transition appeared as a continuous, gradual change in microstructure. The lower weld energy (280/280) produced lower hardness in the stir zone than the higher energy weld (450/450), ~95 HV1 versus ~115 HV1; however, the 280/280 welds showed higher tensile strengths than the 450/450 welds, ~238 MPa as opposed to ~172 MPa. These behaviors in mechanical performance correlated with the temperature histories produced by each set of weld parameters in relation to the precipitation behavior of the alloy. The fracture characteristics of the weldments were notably different with the 450/450 sample fracturing in a quasi-brittle manner with slight plastic deformation and the 280/280 sample fracturing ductilely. A numerical simulation supported the investigation by elucidating the temperature and material flow behavior during the joining process. [ABSTRACT FROM AUTHOR]

The present study investigated the synergistic influence of coal bottom ash (CBA) on the shear strength of concrete. CBA was milled for 2, 6, and 10 h to form grinded CBA (GCBA). "L" shaped specimens were prepared with 10%–30% GCBA and 25%–50% CBA as alternative of Portland cement and natural fine aggregates. Concrete containing 20% GCBA (grinded for 6 h) and 25% CBA reported the highest shear strength owing to pozzolanic reactiveness and filler action. X-ray diffraction, scanning electron microscopy–energy-dispersive spectroscopy and Fourier transform infrared also supported the experimental outcomes. Well fitted mathematical models were derived followed by optimization using desirability function approach recommending 5.71 h of grinding, 26.27% GCBA, and 36.69% CBA as the optimum amount for its successful utilization in concrete. This approach further leads to significant reduction of about 22% in carbon footprints and eco-costs in comparison to conventional concrete. [ABSTRACT FROM AUTHOR]

The detection of impurities in diatomite is a critical issue during the silicon extraction process. Impurities can significantly impact the properties of silicon, compromising the performance of Si solar cells. In the present work, we applied a sensitivity-improved calibration-free LIBS measurement approach to assess the quality of diatomite. Based on the recording of two spectra with different delays between the laser pulse and the detector gate, the method enables the quantification of major, minor, and trace elements. The limits of detection for minor and trace elements were evaluated. Furthermore, we investigated the morphology and properties of the diatomite surface using Energy-Dispersive X-ray Spectroscopy and Scanning Electron Microscopy analysis. This research contributes to process optimization in the fabrication of electronic grade silicon from diatomite for photovoltaic technology and other applications. [ABSTRACT FROM AUTHOR]

The present work investigates the failure of a rear axle hypoid gear that failed during fatigue life testing before meeting the criteria. The failure being in contrary to the historical field failure where the mating pinion gear fails as the primary member became critical and hence detailed failure analysis was carried out. Failure analysis involving fractography, magnetic particle inspection, microstructural analysis, hardness tests, scanning electron microscopy, electron discharge spectroscopy was carried out. Meticulous failure analysis revealed that the hypoid gear failed due to the presence of non-metallic inclusion. SEM and EDX analysis further supported the analysis showing aluminum, calcium, magnesium along with oxygen as major constituents. The work also provided recommendations in the form of process modifications at the steel plant to avoid such kind of failures. [ABSTRACT FROM AUTHOR]

The inevitable residual carbon that normally appears in the polycarbosilane-derived SiC ceramics has notorious effects on the crystallinity and thermal conductivity of SiC ceramic. In this study, nano Si was employed to fully exhaust unwanted residual carbon in a liquid polycarbosilane. Through addition of 12 wt% theoretical nano Si and pyrolysis to 1600 °C, the ceramic yield of the liquid polycarbosilane increased from 72.0 wt% to 81.8 wt% and the C/Si ratio of ceramic product decreased from 1.14 to 0.99. Raman spectroscopy and transmission electron microscope also confirmed that the residual carbon almost completely disappeared. In addition, the crystallization ability of SiC also improved, and as a result dramatical improvement in the thermal conductivity of SiC f /SiC composite was achieved. The reaction mechanism was investigated in detail to understand the residual carbon trapping effect of nano Si during the precursor-to-ceramic conversion. [ABSTRACT FROM AUTHOR]

In this work, steam-exfoliated graphitic carbon nitride was used as a promising basis for the development of photoactive materials for processes induced by visible light. Nanocrystalline cobalt(II,III) oxide, obtained by the solution combustion method followed by heat treatment of the reaction products, was used as a cocatalyst. Nanocomposite materials were prepared by joint ultrasonic treatment of graphite-like carbon nitride and cobalt(II,III) oxide in ethanol. The prepared series of samples with different weight fractions of the oxide (5–10 wt %) was studied by powder X-ray diffractometry, scanning electron microscopy, low-temperature nitrogen adsorption–desorption, and diffuse reflectance electron spectroscopy. The photocatalytic activity of the samples was evaluated in the oxidation of tetracycline hydrochloride. It was found that the rate constant of the photocatalytic reaction reached its maximum value with composites containing 7 wt % Co3O4 (k = 0.0104 min–1). The photovoltaic response studies demonstrated that the presence of cobalt oxide in the samples can significantly decrease the rate of charge carrier recombination to increase the generated current by a factor of 1.2. [ABSTRACT FROM AUTHOR]

Urolithiasis is a medically significant crystallization process affecting the urinary tract. Kidney stones exhibit considerable diversity as they form in complex environments containing various molecules and pathogens. Understanding the formation and occurrence of kidney stones is essential for developing strategies to prevent or reduce the invasiveness of treatments. In this study, we investigated over 300 cases of urolithiasis in Styria, Austria. The composition of the stones was evaluated using infrared spectroscopy and scanning electron microscopy. Most stones were found to be heterogeneous, predominantly composed of calcium oxalate, followed by calcium phosphate. Other components such as struvite, uric acid, and cystine were present to a lesser extent and were more likely to form homogeneous crystals. Analyzing the occurrence of these different stone types provides valuable insights into the formation processes of kidney stones and can aid in the prevention of urolithiasis in the future. [ABSTRACT FROM AUTHOR]

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Ion bombardment during inductively coupled plasma reactive-ion etching and ion-implantation introduces irreparable crystalline damage to gallium nitride (GaN) power devices, leading to early breakdown and high leakage current. To circumvent this, a bi-layer selective area growth mask was engineered to grow up to 3.0 µm thick epitaxy of GaN using plasma-assisted molecular beam epitaxy as an ion-damage-free alternative to standard epitaxial processing routes. The masks and regrown architectures are characterized via SEM, conductive-atomic force microscopy (AFM), x-ray photo electron spectroscopy, Raman, and cathodoluminescence. Mask deposition conditions were varied to modulate and minimize the stress induced during thermal cycling. The resulting mesas exhibit low leakage, attributed to naturally terminated sidewalls as measured by an innovative perpendicular AFM measurement of the regrown sidewall. The regrown sidewall exhibited RMS (root mean square) roughness of 1.50 (±0.34) nm and defect density of 1.36 × 106 (±1.11 × 106) cm−2. This work provides a method to eliminate defect-inducing steps from GaN vertical epitaxial processing and stands to enhance GaN as a material platform for high-efficiency power devices. [ABSTRACT FROM AUTHOR]

ABSTRACT For quantitative analyses of data acquired from x‐ray photoelectron spectroscopy (XPS) instruments to be globally comparable across industry and academia, a consistent and traceable intensity calibration method is required. ISO 5861 was prepared by Technical Committee ISO/TC 201 Surface Chemical Analysis, Subcommittee 7, Electron Spectroscopies, and describes an intensity calibration method for x‐ray photoelectron spectrometers that use quartz‐crystal monochromated Al Ka x‐rays. The method employs low‐density polyethylene reference spectra that are corrected for any instrument geometry and are traceable to the true reference spectra for gold, silver and copper held by the National Physical Laboratory (NPL), UK. This international standard generates a spectrometer relative response function for use in quantitative XPS analysis that is consistent with NPL's intensity calibration method to within 5% relative error. [ABSTRACT FROM AUTHOR]

LaSrCoO4, LaSrNiO4 and LaSrCuO4 were synthesised by the reverse micellar route by using three different microemulsion compositions. The as prepared nanostructures were characterised by powder X‐ray diffraction (PXRD), field emission scanning electron microscopy, energy dispersive X‐ray spectroscopy and transmission electron microscopy. The PXRD of all samples indicate pure phases which crystallize into a tetragonal system. The particle size and shape of nanoparticles varies with microemulsion system. Magnetisation studies suggested that two of the LaSrCoO4 samples display canted antiferromagnetism while the others showed no sign of long‐range ordering. The LaSrNiO4 and LaSrCuO4 samples seemed to show spin glass behaviour. Some of these materials were successfully used as catalysts for organic transformations. The esterification of aldehydes in the presence of alkyl halides and alcohols has been made mild and practicable with a copper catalysed TBHP/DTBP promoting reaction. This approach is suitable to a wide variety of aldehydes, including those that are notoriously difficult to convert through the C(sp2)−H bond scission to produce the required esters in good to outstanding yield. [ABSTRACT FROM AUTHOR]

Narrow gaps between coupled plasmonic nano‐particles show strong optical field enhancements and spectrally adjustable resonance positions, making them attractive for surface enhanced spectroscopies. Gold nanorod dimers formed from nanorod solutions with narrow size distributions are intensely investigated in this context. However, the binding angle of rods coupled at their end faces is usually not controllable. Surprisingly, it is observed that this has only little effect on field enhancement and resonance energies. In this work, gold nanorod dimers are investigated by mapping their plasmon resonances using electron energy‐loss spectroscopy in a scanning transmission electron microscope. For a wide range of dimer orientations, a negligible influence of the angle between the two rods on the bonding and antibonding longitudinal dipole resonances is confirmed, in good agreement with numerical simulations. The results are interpreted via the predominant end‐coupling of the individual nanorod's plasmonic modes, as illustrated by an analytical charge coupling model. In addition, the simulations emphasize that conclusions from experimental data on the gap morphology on the size range of one nanometer can be ambiguous. In any case, the full understanding of the angle‐invariant resonances of nano‐rod dimers can further promote their controlled application in surface enhanced spectroscopy or ‐sensing. [ABSTRACT FROM AUTHOR]

A new bismuth complex with the N-(5,6-dihydro-4H-1,3-thiazin-2-yl)benzamide ligand (L = C11H13N2OS) was synthesized for further medical use. The complex and the ligand exhibit anticancer activity. The structure of the complex was characterized by NMR spectroscopy, inductively coupled plasma atomic emission spectroscopy (ICP-AES), and laser-induced electron transfer desorption/ionization (LETDI) mass spectrometry. The Bi: L ratio is 1: 1; the components are connected by an ionic (ion-dipole) interaction. The reaction of bismuth(iii) chloride with ligand hydrobromide (L•HBr) affords the complex {(C11H13N2OS)3[Bi2Cl9]}. The composition of this complex was confirmed by X-ray diffraction, ICP-AES, and LETDI methods. [ABSTRACT FROM AUTHOR]

The effect of a copper chromite (CC) catalyst on the decomposition of ammonium perchlorate (AP) was investigated using thermo gravimetric analysis (TGA) in conjunction with Fourier transform infrared (FTIR) spectroscopy and electron ionization (EI) mass spectrometry (MS) of the evolved gases. To determine the activation energy of AP samples, the Kissinger–Akahira–Sunose iso-conversional method was used, which shed more light on the effect of copper chromite on both the low-temperature decomposition (LTD) and high-temperature decomposition (HTD) stages. The FTIR and mass spectra revealed species O2, N2O, Cl2, NO2, HCl, HNO3, H2O, ClO, HOCl, and m/z equal to 30. Using a CC catalyst, an increment in the species mole fraction was detected in the HTD stage for all the AP samples. After the catalyst was brought closer, especially when it was embedded with AP, significant changes were observed in the LTD stage as well. MS revealed the formation of new species such as HClO4, ClO4, HClO3, and ClO3 when CC is embedded in AP. Additionally, increased ClO2 due to CC enhances the decomposition reactions near the subsurface. C-DTA proves that the effect in LTD is more due to exothermic decomposition reactions. Consequently, this overall increase in species generation leads to greater mass loss during the LTD stage decomposition. The accelerated path of NO2 production for the pellet of mixed ammonium perchlorate and copper chromite, as well as Copper chromite embedded AP in the LTD stage, is attributed to the presence of ClO2 and the oxidation of CC. These findings demonstrate that the presence of CC near AP causes aging, resulting in a decrease in burn rate over time. Understanding these results will aid in building a detailed chemical kinetic mechanism (DCKM) and open new avenues for researchers to use it wisely in the real world. [ABSTRACT FROM AUTHOR]

Edible films based on biopolymers are used to protect food from adverse environmental factors. However, their ample use may be hindered by some challenges to their mechanical and antimicrobial properties. Despite this, in most cases, increasing their mechanical properties and antibacterial activity remains a relevant challenge. To solve this problem, a possible option is to fill the biopolymer matrix of films with a functional filler that combines high reinforcing and antibacterial properties. In this work, biocomposite films based on a mixture of chitosan and cassava starch were filled with a hybrid filler in the form of bentonite clay particles loaded with ginger essential oil (GEO) in their structure with varied concentrations. For this purpose, GEO components were intercalated into bentonite clay interlayer space using a mechanical capture approach without using surface-active and toxic agents. The structure and loading efficiency of the essential oil in the obtained hybrid filler were analyzed by lyophilization and laser analysis of dispersions, ATR-FTIR spectroscopy, thermogravimetry, and X-ray diffraction analysis. The filled biocomposite films were analyzed using ATR-FTIR spectroscopy, optical and scanning electron spectroscopy, energy dispersive spectroscopy, mechanical analysis under tension, and the disk diffusion method for antibacterial activity. The results demonstrated that the tensile strength, Young's modulus, elongation at the break, and the antibacterial effect of the films increased by 40%, 19%, 44%, and 23%, respectively, compared to unfilled film when the filler concentration was 0.5–1 wt.%. [ABSTRACT FROM AUTHOR]

The concept of electronic orbitals has enabled the understanding of a wide range of physical and chemical properties of solids through the definition of, for example, chemical bonding between atoms. In the transmission electron microscope, which is one of the most used and powerful analytical tools for high‐spatial‐resolution analysis of solids, the accessible quantity is the local distribution of electronic states. However, the interpretation of electronic state maps at atomic resolution in terms of electronic orbitals is far from obvious, not always possible, and often remains a major hurdle preventing a better understanding of the properties of the system of interest. In this review, the current state of the art of the experimental aspects for electronic state mapping and its interpretation as electronic orbitals is presented, considering approaches that rely on elastic and inelastic scattering, in real and reciprocal spaces. This work goes beyond resolving spectral variations between adjacent atomic columns, as it aims at providing deeper information about, for example, the spatial or momentum distributions of the states involved. The advantages and disadvantages of existing experimental approaches are discussed, while the challenges to overcome and future perspectives are explored in an effort to establish the current state of knowledge in this field. The aims of this review are also to foster the interest of the scientific community and to trigger a global effort to further enhance the current analytical capabilities of transmission electron microscopy for chemical bonding and electronic structure analysis. [ABSTRACT FROM AUTHOR]

The SPS-prepared SiC without any additives was irradiated with 15.9 MeV Si ions at room temperature and 500 °C. The damage behavior was investigated by grazing incident X-ray diffraction (GIXRD) spectroscopy, Raman spectroscopy and transmission electron microscopy (TEM). GIXRD and Raman spectra show that the disorder of SiC increases and the lattice swelling occurs with the increase of irradiation at room temperature. High temperature irradiation was associated with the reduction of swelling and the recovery of disorder. TEM results indicate that at room temperature, with increasing dose, the material transitions from slight amorphization to complete amorphization. The amorphization dose is estimated to be around 1.2 dpa. The combined effects of stacking faults, high-energy ions accompanied by higher electronic energy loss inducing displacement cascades, and cascade-induced annealing delay damage accumulation, leading to an increased critical dose for amorphization. Moreover, the transient thermal spikes due to higher electronic energy loss, leading to defect annealing and the formation of Frank loops at lower irradiation temperatures. [ABSTRACT FROM AUTHOR]

A novel friction processing method is used to join Al-Cu sheets in lap configuration without any significant deformation or thickness depletion of parent metals. A pin less, flat shouldered tool is rotated and plunged against a sacrificial top sheet to initiate localised melting at the joint interface. Effect of addition of SiC particles at the joint interface on resulting weld microstructure, interface strength, and joint electrical resistance is studied in this work. Diffusion reaction of SiC particles with Al and Cu results in melting of the interface at around 530 °C. The peak temperature in weld zone with SiC particles is significantly lower than the Al-Cu eutectic temperature and melting points of Al, Cu. Cross-sectional scanning electron micrographs, fractographs, electron dispersive spectroscopy, X-ray diffraction, lap shear, T peel tests, and joint electrical resistance measurements are used to investigate pure Al-Cu and Al-SiC-Cu weld joints for different SiC particle concentrations. SiC particles are found to enhance joint strength through generation of fine eutectic microstructures with sub-micron lamellar spacing and through formation of uniformly distributed nano-precipitates. The highest peel strength achieved with the SiC interlayer is around 70 % higher than that for corresponding pure Al-Cu welds. Despite formation of thick hypereutectic region towards Cu side, with larger volume percentage of "lumps of intermetallics", there is a clear diversion of fracture path from the intermetallics rich region towards the SiC-eutectic boundary of the interface region in Al-SiC-Cu welds. Additionally, SiC interlayer is seen to result in lower percentage rise in joint resistance with temperature. However, SiC interlayer results in a marginal increase in joint electrical resistance. Thus, addition of SiC particles at Al-Cu joint interface is recommended for significantly enhancing the joint strength with no significant change in joint electrical resistance. [Display omitted] • Diffusion of Si from SiC particles into Al-Cu melt reduces the interface melting temperature. • SiC particles expose nascent surfaces of Al-Cu, promote interdiffusion and enhance wetting. • Nanoprecipitates are seen to form in the ''crumbled" eutectic melt region. • SiC particles increase the fracture energy with a highly jagged fracture surface. • Joints with SiC interlayer exhibit higher joint strength at nearly similar electrical resistance. [ABSTRACT FROM AUTHOR]