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Conical intersections are known to play a vital role in many photochemical processes. The breakdown of the Born–Oppenheimer approximation in the vicinity of a conical intersection causes exciting phenomena, such as the ultrafast radiationless decay of excited states. The passage of a molecule through a conical intersection creates a coherent superposition of electronic states via nonadiabatic couplings. Detecting this coherent superposition may serve as a direct probe of the conical intersection. In this paper, we theoretically demonstrate the use of coherent spontaneous emission in samples with long-range order for probing the occurrence of a conical intersection in a molecule. Our simulations show that the spectrum contains clear signatures of the created coherent superposition of electronic states. We investigate the bandwidth requirements for the x-ray probes, which influence the observation of coherent superposition generated by the conical intersection. [ABSTRACT FROM AUTHOR]

The characteristic x-ray emission direction of a material indicates the direction of the bonding orbitals and spatial symmetry of the electron orbitals. Accordingly, the intensity of x-ray emission, which varies with the direction of emission and crystal orientation, provides crucial information regarding anisotropic electronic structures. This study utilized angle-resolved soft x-ray emission spectroscopy (SXES) on a layered material, NaAlSi, to ascertain the spatial distribution of the valence electrons. Distinct alterations in the spectral intensity distributions were observed in the Al–L2,3 and Si–L2,3 spectra with respect to the emission angle. To interpret the anisotropic SXES spectra, the spatial distribution of each valence electronic state was simulated using first-principle calculations. Although the anisotropic emission intensity could not explain the symmetry of the spatial distributions of the isolated s and d atomic orbitals, the anisotropy of the SXES spectra could be interpreted as the spatial distribution of these orbitals when hybridized with p orbitals. Furthermore, the spectral structure corresponding to the electronic states near the Fermi level reflected the characteristics of the d orbitals. Therefore, angle-resolved SXES measurements can effectively discern the spatial distribution of hybridized electron orbitals with specific energy levels, which could enhance techniques related to electron distribution analysis, with potential applications in material science and electronic structure characterization. [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]

Cu3N films are investigated utilizing direct current magnetron sputtering from the Cu target in an Ar/N2 mixed sputtering gas. X-ray diffractive analysis, Ultra-violet absorption spectroscopy, X-ray dispersive spectroscopy, atomic force microscopy, field-emission scanning electron microscopy, Hall measurements, and I–V characteristic measurements are used to investigate the properties of the films. The study findings initially obtained films with a Cu3N composition at the appropriate substrate temperature of 80 °C. When the N2:(Ar + N2) gas ratio is more than 50%, the electrical property of films switches from n-type to p-type. The film obtains the greatest crystal quality and the best p-type electric property at the N2:(Ar + N2) gas ratio of 70%, with resistivity, hole concentration, and hole mobility of 1.18 × 10–2 Ωcm, 9.8 × 1019 cm−3, and 5.4 cm2V−1 s−1, respectively. A p–n Cu3N homojunction cell has an efficiency of 0.21%. [ABSTRACT FROM AUTHOR]

Transition metal complexes, particularly copper hydrides, play an important role in various catalytic processes and molecular inorganic chemistry. This study employs synchrotron hard X‐ray spectroscopy to gain insights into the geometric and electronic properties of copper hydrides as potential catalysts for CO2 hydrogenation. The potential of high energy resolution X‐ray absorption near‐edge structure (HERFD‐XANES) and valence‐to‐core X‐ray emission (VtC‐XES) is demonstrated with measurement on Stryker's reagent (Cu6H6) and [Cu3(μ3‐H)(dpmppe)2](PF6)2 (Cu3H), alongside a non‐hydride copper compound ICu(dtbppOH) (Cuy−I). The XANES analysis reveals that coordination geometries strongly influence the spectra, providing only indirect details about hydride coordination. The VtC‐XES analysis exhibits a distinct signal around 8975 eV, offering a diagnostic tool to identify hydride ligands. Theoretical calculations support and extend these findings by comparing hydride‐containing complexes with their hydride‐free counterparts. [ABSTRACT FROM AUTHOR]

Nanolubricants are dispersions of nanomaterials in a lubricating base. In this work, polyethylene glycol (PEG) was modified with graphene (G) and copper oxide (CuO) to obtain a nanolubricant (NL). The nanolubricants were prepared and their physicochemical and tribological properties were evaluated. The base and the nanomaterials were evaluated using Fourier-transform infrared spectrometry (FTIR), field-emission scanning electron microscopy coupled with energy dispersive spectroscopy (FE-SEM-EDS), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Raman spectroscopy (Raman). Rheology and Tribology tests were also performed using a four-ball tester according to ASTM 2783. The results showed that nanolubricants have a Newtonian behavior and the viscosity was not significantly modified with the additives. The weld point obtained for the nanolubricants was 160 kgf. In addition, when compared to the PEG, the size of the wear scars was reduced by 9.6% (PEG with 0.01% w/w of CuO) and 35.3% (PEG with 0.05% w/w of CuO and G). The wear protection provided by G is higher than the protection provided by CuO. When the two additives were added, the wear protection increased, and a synergistic effect was observed. Two protection mechanisms were observed in the SEM: rolling bearing/ball effect (CuO) and deposition of G at valleys and peaks of the surface roughness. This article shows novel results related to a laboratory evaluation of nanolubricants in a typical tribological test (four-ball). A novel result was observed in the synergistic effect between the two additives (graphene and CuO) determined by the wear mechanism observed in the tests. [ABSTRACT FROM AUTHOR]

In this research, 0.5 % platinum (Pt)/HPAs/MCM‐41 (Mobil Composition of Matter No. 41) bifunctional catalysts (with different weight percentages of phosphotungstic acid (HPW) and silicotungstic acid (HSiW)) were synthesized for use in the n‐butane isomerization. The synthesized catalysts were characterized by X‐ray diffraction, X‐ray fluorescence spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, Brunauer–Emmett–Teller, and ammonia temperature‐programmed desorption analyses. The best catalytic activity and highest initial isobutane yield at 250 °C, weight hourly space velocity of 0.15 h−1, and H2/nC4 molar ratio of 3:1 belonged to 0.5 %Pt/20 % HPW/MCM‐41 (41 %) and 0.5 % Pt/40 % HSiW/MCM‐41 (45 %) samples. Subsequently, the yield of isobutane over these catalysts was evaluated and optimized by a central composite experimental design. According to the quadratic model, the maximum isobutane yield under optimal operating conditions was 34.5 % and 41.36 %, respectively, for 0.5 % Pt/20 % HPW/MCM‐41 and 0.5 % Pt/40 % HSiW/MCM‐41 catalysts. [ABSTRACT FROM AUTHOR]

The microstructural characterization of lunar agglutinate samples serves many essential purposes in lunar science and cosmochemistry, from understanding the formation process of lunar regolith to preparing for human activity on the Moon. In this study, an advanced correlative characterization methodology was employed to examine the microstructure of a lunar agglutinate particle retrieved from the Apollo 11 mission. The multimodal characterization efforts were centered around 3‐D x‐ray computed tomography (XCT) and were complemented by 2‐D techniques, including scanning electron microscopy and energy‐dispersive x‐ray spectroscopy. The nondestructive nature of the XCT allowed us to preserve the lunar dust particles, while its 3‐D nature allowed us to extract meaningful microstructural information inaccessible via traditional 2‐D characterization techniques. The multimodal correlative analysis further allowed us to identify the compositional and microstructural features of the agglutinate. These observations were linked to the formation process of the agglutinate to inform a hypothesis on the dynamic formation sequence of lunar regolith. [ABSTRACT FROM AUTHOR]

Over 200 samples from colourants appeared in 50 monuments in Iran dated back to the 11th century up to the 15th century were identified using micro‐X‐ray fluorescence (μ‐XRF), micro‐Raman spectroscopy (μ‐Raman), polarized light microscopy (PLM), and scanning electron microscopy–energy dispersive X‐ray spectrometry (SEM‐EDS). Whereas red ochre, red lead, vermilion, and an organic red dye were identified as red colourants, ultramarine blue, azurite, and indigo were the blue colourants occurred in the wall decorations. In addition, atacamite was the only green pigment identified on the wall paintings and stucco decorations, and carbon black was identified as black pigment. We also show that gold leaf and tin foil have been used in gilding decorations. Furthermore, we were able to discern yellow ochre together with orpiment, natrojarosite, and crocoite in a number of architectural decorations. Moreover, we show that huntite and gypsum are used as white preparation layer of the wall decorations in Iran. Periods of emergence of particular pigments have been discussed and regional preferences in the use of certain pigments are argued. An extensive discussion is provided to compare the colourant appeared on wall decoration with those appeared on illuminated manuscripts in the Persianate world. [ABSTRACT FROM AUTHOR]

Shijia Yucun site is a northwestern settlement from the Zhou period (1046–221 BCE). Faience beads used as a personal ornament and coffin decoration are notable among plenty of funerary objects. Thirteen faience objects are determined using analytical electron probe micro‐analysis (EPMA) and scanning electron microscopy‐energy dispersive X‐ray spectroscopy (SEM–EDS). The information on their provenance indicates that the types of faience beads around bodies include the mixed‐alkali faience from Europe or the Eurasian Steppe, the soda‐enriched faience from West Asia, and the local products rich in potash. However, faience samples adorning coffins are all local products, and the quality is rougher compared to the faience decorating the body. This unique feature is hardly found in other tombs of Zhou elites. As faience was a precious personal ornament in other stronger polities, it was already available as a general coffin decoration in such a small‐economy feudal state, so faience samples decorating coffins were not likely to be precious gifts from other elites. It is reasonable to assume that faience beads adorning coffins might have been made near the ruins. This investigation is significant to reveal the cultural exchange in the western frontier of the Zhou realm that dates back to the power decline of the Western Zhou period and highlight a possible high‐potash faience production area. [ABSTRACT FROM AUTHOR]

In this work, flutamide‐loaded tungsten disulfide nanosheets modified thermo-responsive polymer (N-vinylcaprolactam) were prepared as a dual responsive system for targeted delivery of flutamide to tumor cells. The prepared nanocarrier was characterized using field-emission scanning electron microscopy, atomic force microscopy, Zeta potential, Fourier-transform infrared spectroscopy, X-ray diffraction, and thermal gravimetric analyses. The behavior of flutamide sorption was investigated by non-linear isotherm models that the equilibrium data well fitted with the Langmuir model. The maximum sorption capacity of the drug as computed from the non-linear Langmuir model was 7.33 mg g–1. Moreover, the kinetics of the sorption procedure followed by the non-linear pseudo-2nd-order kinetic model with a higher regression coefficient (R2 = 0.9965). The pH and temperature-responsive nanocarrier released minimal amounts (15.75%) of the drug at a simulated physiological medium (pH 7.4; T = 37 °C). In contrast, a fast release of the drug (77.52%) was shown in a simulated cancer medium at a high temperature after 6 h (pH 5.6; T = 45 °C). Furthermore, the released amounts of drug from the nanocarrier can be regulated by adjusting the near-infrared laser irradiation. Dual responsive nanocarrier shown targeted cytotoxicity towards PC-3 cells with milder cytotoxicity towards normal cells. The nanocarrier showed two-fold higher cytotoxicity under near-infrared laser irradiation in comparison to the nanocarrier without irradiation in the PC-3 cell lines. Enhanced antitumor efficacy by photo-thermal therapy was achieved with near-infrared laser irradiation. All these data suggest that the pH and temperature dual responsive nanocarrier is a biocompatible and efficient candidate for the specific delivery of flutamide to PC-3 cells and could be utilized as a prostate cancer specific drug delivery system. [ABSTRACT FROM AUTHOR]

In this study, tin ferrite nanoparticles (SnFe2O4) were synthesized using sol–gel, solvothermal, and co-precipitation methods, and the effect of annealing temperature on the formation of structures annealed at T = 350 °C, T = 450 °C, and T = 550 °C was investigated. The X-ray diffraction (XRD), UV–Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and field-emission electron microscopy (FESEM) were used to investigate the structural, optical, and surface morphological properties. The results obtained from the structural analysis of the synthesized samples showed that the SFO4 sample with the spinel phase synthesized by solvothermal had the highest intensity of the preferred peak (311) and a more uniform grain size. The FESEM images of the nanostructures showed cubic and polyhedral grains with cluster growth. The optical absorbance of the samples was studied using UV–Vis spectroscopy within the wavelength range of λ = 190–1100 nm. The highest absorption in the samples was related to SFO6, and the band gap showed an increasing trend with temperature in region Eg = 2.20–2.85 eV. The reason for the increase of band gap with increasing temperature is the formation of independent oxide phases in the nanoparticle's composition. The tin ferrite oxide spinel sample SFO4 showed a value of 2.53 eV. From the UV–Vis analysis, the values of refractive index (n), extinction coefficient (k), dielectric constant (ϵ ), Urbach energy (Eu) and reflection coefficient were studied. The results of the FTIR analysis in the fingerprint region confirm the vibrations caused by the presence of Sn–O and Fe–O metal oxides. The presence of metal oxide bonds indicates the formation of tin ferrite structure. [ABSTRACT FROM AUTHOR]

In this work, pure phase and carbon/ZnSn(OH)6 samples were synthesized by a hydrothermal method. The composite sample's structure, morphology, and functional groups were investigated by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. Subsequently, ZnSn(OH)6 samples were modified with different carbon contents, and their humidity-sensing properties were investigated. The introduction of carbon increased the specific surface area of pure ZnSn(OH)6 samples, thus significantly improving the sensors' humidity sensing response. The C10-ZnSn(OH)6 sensor exhibited a high response, up to three orders of magnitude, a humidity hysteresisof 13.5%, a fast response time of 3.2 s, and a recovery time of 24.4 s. The humidity sensor's possible humidity sensing mechanism was also analyzed using the AC complex impedance puissance method with a simulated equivalent circuit. These results revealed that ZnSn(OH)6 can effectively detect ambient humidity and that the introduction of carbon significantly improves its humidity-sensing performance. The study provides an effective strategy for understanding and designing ZnSn(OH)6-based humidity sensors. [ABSTRACT FROM AUTHOR]

This study investigates the influence of ligand charge on transition energies in a series of CuN2S2 complexes based on dithiocarbazate Schiff base ligands using Cu K-edge X-ray absorption spectroscopy (XAS) and Kβ valence-to-core (VtC) X-ray emission spectroscopy (XES). By comparing the formally Cu(II) complexes [CuII(HL1)] (HL12− = dimethyl pentane-2,4-diylidenebis[carbonodithiohydrazonate]) and [CuII(HL2)] (HL22− = dibenzyl pentane-2,4-diylidenebis[carbonodithiohydrazonate]) and the formally Cu(III) complex [CuIII(L2)], distinct changes in transition energies are observed, primarily attributed to the metal oxidation state. Density functional theory (DFT) calculations demonstrate how an increased negative charge on the deprotonated L23− ligand stabilizes the Cu(III) center through enhanced charge donation, modulating the core transition energies. Overall, significant shifts to higher energies are noted upon metal oxidation, emphasizing the importance of scrutinizing ligand structure in XAS/VtC XES analysis. The data further support the redox-innocent role of the Schiff base ligands and underscore the criticality of ligand protonation levels in future spectroscopic studies, particularly for catalytic intermediates. The combined XAS-VtC XES methodology validates the Cu(III) oxidation state assignment while offering insights into ligand protonation effects on core-level spectroscopic transitions. [ABSTRACT FROM AUTHOR]

The ability to study chemical dynamics on ultrafast timescales has greatly advanced with the introduction of X-ray free electron lasers (XFELs) providing short pulses of intense X-rays tailored to probe atomic structure and electronic configuration. Fully exploiting the full potential of XFELs requires specialized experimental endstations along with the development of techniques and methods to successfully carry out experiments. The liquid jet endstation (LJE) at the Linac Coherent Light Source (LCLS) has been developed to study photochemistry and biochemistry in solution systems using a combination of X-ray solution scattering (XSS), X-ray absorption spectroscopy (XAS), and X-ray emission spectroscopy (XES). The pump–probe setup utilizes an optical laser to excite the sample, which is subsequently probed by a hard X-ray pulse to resolve structural and electronic dynamics at their intrinsic femtosecond timescales. The LJE ensures reliable sample delivery to the X-ray interaction point via various liquid jets, enabling rapid replenishment of thin samples with millimolar concentrations and low sample volumes at the 120 Hz repetition rate of the LCLS beam. This paper provides a detailed description of the LJE design and of the techniques it enables, with an emphasis on the diagnostics required for real-time monitoring of the liquid jet and on the spatiotemporal overlap methods used to optimize the signal. Additionally, various scientific examples are discussed, highlighting the versatility of the LJE. [ABSTRACT FROM AUTHOR]

The nucleation of carbonate-containing apatite on the biomaterials surface is regarded as a significant stage in bone healing process. In this regard, composites contained hydroxyapatite (Ca10(PO4)6(OH)2, HA), wollastonite (CaSiO3, WS) and polyethersulfone (PES) were synthesized via a simple solvent casting technique. The in-vitro bioactivity of the prepared composite films with different weight ratios of HA and WS was studied by placing the samples in the simulated body fluid (SBF) for 21 days. The results indicated that the the surface of composites containing 2 wt% HA and 4 wt% WS was completely covered by a thick bone-like apatite layer, which was characterized by Grazing incidence X-ray diffraction, attenuated total reflectance–Fourier transform infrared spectrometer, field emission electron microscopy and energy dispersive X-ray analyzer (EDX). The degradation study of the samples showed that the concentration of inorganic particles could not influence the degradability of the polymeric matrix, where all samples expressed similar dexamethasone (DEX) release behavior. Moreover, the in-vitro cytotoxicity results indicated the significant cyto-compatibility of all specimens. Therefore, these findings revealed that the prepared composite films composed of PES, HA, WS and DEX could be regarded as promising bioactive candidates with low degradation rate for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

A fluorescent sensor, 5-((2-hydroxynaphthalen-1-yl)methyleneamino)benzene-1,3-dicarboxylic acid (coded as SB), containing both π-π interacting sites (such as π-electron-rich moieties) and hydrogen bonding (H-bonding) interacting sites (such as highly acidic protons) has been developed via high yield reflux method. It was characterized by the various analytical techniques such as Fourier transform-infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1 H-NMR), thermogravimetric analysis (TGA), field emission scanning electron microscope (Fe-SEM), elemental mapping, and UV − visible spectroscopy etc. The spectral response of the as-synthesized SB sensor has been investigated for various nitro explosives (NEs). It has been found that the SB sensor selectively and sensitive sense highly toxic 2,4,6-trinitrophenol (TNP) via the "turn-off" quenching response. Its limit of detection for TNP was calculated to be 30 ppb. Spectral overlap, detailed mechanistic studies for their mode of action, and density functional theory (DFT) calculations reveals that photo-induced electron transfer process (PET), fluorescence energy transfers process (FRET), and electrostatic interactions (i.e. H-bonding) are the key factors for the turn-off response of SB towards TNP. Notably, the synthesis of the sensor is cost-effective, energy efficient, and economic. [ABSTRACT FROM AUTHOR]

The formation of black crust upon building stones and the resulting damage depend upon the fabric of the stone and atmospheric effects. The formation of black crust on limestone occurs more rapidly and distinctly compared to stones such as granite and sandstone, in which the mineral calcite is absent or in small quantities in its composition. In this study, black crust formation developed on the surfaces of limestone in İstanbul and Edirne, where important historical monuments belonging to the Byzantine and Ottoman Empires are located, were examined visually, microscopically, and experimentally. The factors causing the development of this crust and their effects on weathering were determined, and comparative analyses of the black crust with the sub-layer stone were made. In addition, by classifying the morphology, chemical structure, mineralogical composition, and damage to the stone by the black crust, chemical, and physical weathering that causes surface deterioration on the stone and back of the crust were examined. Physical (Schmidt hammer), mineralogical (X-ray diffraction), petrographic (polarizing microscopy), chemical (inductively coupled plasma-emission spectrometry, inductively coupled plasma-mass spectrometry, Fourier transform infrared spectrometry), and microstructural (field emission scanning electron microscopy with energy dispersive X-ray spectrometry) analyses were carried out to characterize this process. The black crust formation on limestone was shown to be caused by sulfation. [ABSTRACT FROM AUTHOR]

Background: Researchers are keen to reduce the over potential value through fabrication of electrocatalyst consisted of environmentally benign and inexpensive material. Supercapacitors on the other hand have gained immense attention in recent years as an energy storage device due to the high power density potential of these devices as compared to conventional batteries based storage system. Aim: The research aims to synthesize nanoscale transition metal oxides (TMO) through green route. TMO based nanomaterials have vast role in energy related applications. Materials & methods: In this study, organic compounds of A. Viridis were used as reducing and stabilizing agents in the synthesis of binary nanocomposite Sb2O3-ZrO2. The synthesized nanocomposite was characterized using xray diffraction, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, field emission scanning electron microscopy and energy dispersive spectroscopy. The electrode material was analyzed for supercapacitor potential using cyclic voltammetry and galvanostatic charge discharge techniques. HER and OER studies were also conducted using electrochemical impedance spectroscopy and linear sweep voltammetry. The synthesized material was also tested for stability. Results & discussion: The crystal size was 15.9 nm. Optical band gap of 2.55 eV was obtained through Tauc plot. The capacitance value of 339.8 F/g at 2 mV/s and the specific capacitance of 100.6 F/g was obtained at 1 A/g. The overpotential value of 201 mV and Tafel value of 121 mV/dec was recorded for the HER, whereas the lower Tafel value of 106 mV/dec and over potential value of 383 mV was determined for OER. Electrode showed promising stability up to various cycles in case of both applications. Conclusion: The obtained results revealed the promising performance with excellent stability of fabricated electrode for super capacitor as well as water splitting studies. [ABSTRACT FROM AUTHOR]

Cadmium (Cd), a heavy metal that is very harmful to both the environment and human health, makes it difficult to detect in environmental and analytical research. However, given the adverse impacts, a remedy is urgently required. Due to its special benefits, electrochemical approaches have recently attracted a lot of interest for the detection of Cd(II) ions. We have prepared zinc selenide/graphene oxide (ZnSe/GO) nanocomposites and characterized its structural, compositional, and morphological properties using X-ray diffraction, elemental mapping, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy, to fabricate an efficient electron mediator for electrochemical sensor. Results of the experiments proved that the device is reliable in Cd(II) detection with 45.54 µM limit of detection (LOD) and 138.00 µM limit of quantification (LOQ). The sensor showed a linear range of output current at 100–700 µM Cd(II) with the coefficient of correlation (R2 = 0.996). Interferents have a negligible effect on the response of the sensor. [ABSTRACT FROM AUTHOR]

A high-flux beamline optimized for non-resonant X-ray emission spectroscopy (XES) in the tender X-ray energy range has been constructed at the BESSY II synchrotron source. The beamline utilizes a cryogenically cooled undulator that provides X-rays over the energy range 2.1 keV to 9.5 keV. This energy range provides access to XES [and in the future X-ray absorption spectroscopy (XAS)] studies of transition metals ranging from Ti to Cu (Kα, Kβ lines) and Zr to Ag (Lα, Lβ), as well as light elements including P, S, Cl, K and Ca (Kα, Kβ). The beamline can be operated in two modes. In PINK mode, a multilayer monochromator (E/ΔE ≃ 30-80) provides a high photon flux (1014 photons s-1 at 6 keV and 300 mA ring current), allowing non-resonant XES measurements of dilute substances. This mode is currently available for general user operation. X-ray absorption near-edge structure and resonant XAS techniques will be available after the second stage of the PINK commissioning, when a high monochromatic mode (E/ΔE ≃ 10000-40000) will be facilitated by a double-crystal monochromator. At present, the beamline incorporates two von Hamos spectrometers, enabling time-resolved XES experiments with time scales down to 0.1 s and the possibility of two-color XES experiments. This paper describes the optical scheme of the PINK beamline and the endstation. The design of the two von Hamos dispersive spectrometers and sample environment are discussed here in detail. To illustrate, XES spectra of phosphorus complexes, KCl, TiO2 and Co3O4 measured using the PINK setup are presented. [ABSTRACT FROM AUTHOR]

Various X-ray techniques are employed to investigate specimens in diverse fields. Generally, scattering and absorption/emission processes occur due to the interaction of X-rays with matter. The output signals from these processes contain structural information and the electronic structure of specimens, respectively. The combination of complementary X-ray techniques improves the understanding of complex systems holistically. In this context, we introduce a multiplex imaging instrument that can collect small-/wide-angle X-ray diffraction and X-ray emission spectra simultaneously to investigate morphological information with nanoscale resolution, crystal arrangement at the atomic scale and the electronic structure of specimens. [ABSTRACT FROM AUTHOR]

In this work, the electrochemical behavior and sensitive voltammetric determination of D-penicillamine are described by using a carbon paste electrode modified with WO3 nanorods and ionic liquid. The as-synthesized WO3 nanorods were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Cyclic voltammetric measurements showed that D-penicillamine was irreversibly oxidized at WO3 nanorods/ionic liquid/carbon paste electrode at 710 mV in pH 7.0 phosphate buffer solution. The peak current of D-penicillamine was increased approximately 6.2 fold at WO3 nanorods/ionic liquid/carbon paste electrode compared to unmodified carbon paste electrode due to a good electrocatalytic efficiency of WO3 nanorods and ionic liquid. A wide linear range response between oxidation peak current and D-penicillamine concentration (0.08–235.0 µM) was observed using differential pulse voltammetry. The limit of detection for D-penicillamine on WO3 nanorods/ionic liquid/carbon paste electrode is found to be 0.03 µM. Studies conducted in the analysis of D-penicillamine capsule and urine samples confirmed that the developed sensor exhibits good applicability for accurate and sensitive voltammetric determination of D-penicillamine in real samples. [ABSTRACT FROM AUTHOR]

Spherically bent crystal analyzers (SBCAs) are the dominant high-resolution hard X-ray optic in the ongoing rebirth of laboratory-based X-ray absorption fine structure (XAFS) and X-ray emission spectroscopy (XES) as well as in synchrotron methods such as high energy resolution fluorescence detection (HERFD) and non-resonant X-ray Raman scattering (XRS). In the overwhelming majority of cases, SBCAs are implemented in a 'symmetric' configuration on the Rowland circle, wherein the diffracting crystal plane is nominally coincident with the analyzer surface. We report here comprehensive investigations of 'asymmetric' operation of SBCA on the Rowland circle, wherein the diffracting crystal plane is not coincident with the optical surface of the analyzer. First, we have developed a laboratory spectrometer for XAFS and XES that is specialized for asymmetric SBCA operation. We find several benefits, including the capacity to use a single SBCA over a very wide energy range via 'hkl hopping' and the frequent ability to eliminate Johann error, the most prevalent energy-broadening mechanism when using SBCA symmetrically on the Rowland circle. Second, we expand these ideas to synchrotron facilities with a demonstration study of HERFD and XRS where asymmetric operation also provided advantage. Our results suggest that large-array systems for HERFD augmented with an additional mechanical degree of freedom could streamline user operation and also indicate benefits to XRS in the asymmetric configuration, where larger solid angle, larger sample-to-detector distance, and decreased Johann error can be achieved simultaneously. [ABSTRACT FROM AUTHOR]

Methods for computing core-level ionization energies using self-consistent field (SCF) calculations are evaluated and benchmarked. These include a "full core hole" (or "ΔSCF") approach that fully accounts for orbital relaxation upon ionization, but also methods based on Slater's transition concept in which the binding energy is estimated from an orbital energy level that is obtained from a fractional-occupancy SCF calculation. A generalization that uses two different fractional-occupancy SCF calculations is also considered. The best of the Slater-type methods afford mean errors of 0.3–0.4 eV with respect to experiment for a dataset of K-shell ionization energies, a level of accuracy that is competitive with more expensive many-body techniques. An empirical shifting procedure with one adjustable parameter reduces the average error below 0.2 eV. This shifted Slater transition method is a simple and practical way to compute core-level binding energies using only initial-state Kohn–Sham eigenvalues. It requires no more computational effort than ΔSCF and may be especially useful for simulating transient x-ray experiments where core-level spectroscopy is used to probe an excited electronic state, for which the ΔSCF approach requires a tedious state-by-state calculation of the spectrum. As an example, we use Slater-type methods to model x-ray emission spectroscopy. [ABSTRACT FROM AUTHOR]

The risk of bacterial infections is a significant challenge faced frequently in the use of implants or scaffolds for bone regeneration. Therefore, this study focusses on the development and characterisation of novel β tricalcium phosphate (βTCP) scaffolds co-doped with silver and silicon, along with composites coated with antibiotic-loaded poly(3-hydroxybutyrate) (P(3HB)) layers. The successful incorporation of silver and silicon dopants while maintaining the formation of βTCP phase was confirmed using X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS) analysis. The developed materials demonstrated comparable total and open porosity (∼64–70 vol%), suggesting high interconnectivity between pores conducive to nutrient transport and tissue repair. The increase in compressive strength was achieved for both doped (4.73 ± 0.79 MPa) and P(3HB) coated (5.79 ± 0.92 MPa) scaffolds due to the fine bioceramic microstructure and polymeric coating. Silver and silicon-modified βTCP demonstrated enhanced growth inhibition of Gram-negative (Pseudomonas aeruginosa , Escherichia coli) and Gram-positive (Staphylococcus aureus) bacterial strains in vitro compared to the pure βTCP. P(3HB) coatings, enriched with gentamicin or ceftazidime, exhibited burst and sustained release of the antibiotics from the scaffolds up to 120 h further intensifying the bacteria-killing capability, with evident inhibition zones observed in vitro. Moreover, the composites exhibited apatite-forming ability, suggesting their bioactive potential. In vivo evaluation using Caenorhabditis elegans demonstrated the lack of toxicity of the tested materials. The simultaneous incorporation of the dopants and antibiotic-loaded P(3HB) coatings not only offer a dual antibacterial approach but may also facilitate bone regeneration. However, further in vitro and in vivo investigations are needed to assess their potential in clinical application. [ABSTRACT FROM AUTHOR]

Implementing a newly developed spectrometer for the soft x‐ray range of (35–130) eV based on reflection zone plates was successfully accomplished on an electron probe microanalyzer. In this context, we present the first spectra acquired using this setup, including those of elements such as Be (Kα), C (Kα), Mg (L2,3), Al (L2,3), and Si (L2,3). We have also conducted an analysis of several lithium compounds and measured the emission of Li Kα from metallic Li, LiF, and LiNbO3. Some of the results were compared with density functional theory calculations. The spectrum obtained for the lithium‐bearing mineral amblygonite Li0.75Na0.25Al(PO4)F0.75(OH)0.25 is chosen to discuss some of the challenges faced. [ABSTRACT FROM AUTHOR]

BACKGROUND: Medical titanium and titanium alloy have achieved good therapeutic effects in clinical applications, but there are still some phenomena such as peri-implant inflammation, loosening and shedding. OBJECTIVE: To explore the physicochemical properties of graphene oxide coating materials and their effects on bone marrow mesenchymal stem cells. METHODS: (1) Hydroxyapatite coating and graphene oxide/hydroxyapatite composite coating were prepared on a titanium surface by electrochemical deposition. The surface morphology, phase structure, functional groups, elemental composition and surface hydrophilicity of the coating were analyzed by scanning electron microscopy, X-ray energy dispersion spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy, and contact angle measurement instrument. (2) Mouse bone marrow mesenchymal stem cells were isolated and cultured and inoculated on pure titanium, hydroxyapatite coating and graphene oxide/hydroxyapatite composite coating, respectively. CCK-8 assay and scanning electron microscopy were used to evaluate the proliferation, morphology and growth status of the coated cells. RESULTS AND CONCLUSION: (1) Scanning electron microscopy and X-ray energy dispersion spectra showed that the surface of graphene oxide/hydroxyapatite composite coating was more flat, compact and uniform than that of hydroxyapatite coating and pure titanium. X-ray photoelectron spectroscopy, X-ray diffraction and Raman spectroscopy showed that hydroxyapatite coating and graphene oxide/hydroxyapatite composite coating were successfully prepared on the surface of the titanium sheet. The hydrophilicity of graphene oxide/hydroxyapatite composite coating was better than that of hydroxyapatite coating and pure titanium. (2) CCK-8 assay showed that the number of bone marrow mesenchymal stem cells on the surface of the three groups increased with the extension of co-culture time. On days 1, 4, and 7, the proliferative absorbance of the cells on the graphene oxide/hydroxyapatite composite coating was higher than that on hydroxyapatite coating and pure titanium (P < 0.000 1). Scanning electron microscopy after 4 days of co-culture showed that bone marrow mesenchymal stem cells on the surface of the three groups of materials were fusiform. The cells on the surface of graphene oxide/hydroxyapatite composite coating showed good tensile properties and were polygonal. Multiple antennae could be seen attached to the coating surface at the edge of the cells, and the elongation of the filamentous foot on the surface was more than that on pure titanium and hydroxyapatite coatings. (3) The results show that graphene oxide/ hydroxyapatite composite coating material is a kind of coating material with excellent physicochemical and biological properties. [ABSTRACT FROM AUTHOR]

This work has demonstrated the photocatalytic activity of NiFe2O4/r-GO based photocatalyst. The efficient and low-cost synthetic method has been used for the synthesis of NiFe2O4/r-GO. The NiFe2O4/r-GO was characterized using different analytical methods such as Fourier transform infrared spectroscopy, powder X-ray diffraction method, Scanning electron microscopy, and energy-dispersive X-ray spectroscopy methods. The maximum Rhodamine degradation was found to be 96.8 (±1.3) % within 140 min. The maximum dye degradation capacity of NiFe2O4/r-GO is 16.8 (±0.4) mg/g and the pseudo second order rate constant was observed to be 5.9 (±1.1) g/mg/min. Freundlich isotherm model was found more favorable than Langmuir model for the degradation of RhB. The NiFe2O4/r-GO was re-utilized five times. In each step, a remarkable percentage of dye degradation was found. After fifth cycle, the dye degradation was found to be 42.2 (±1.1) %. Further, on the basis of experimental findings, NiFe2O4/r-GO was found to be a good photocatalyst and can be applied in the treatment of wastewater containing organic pollutants under large-scale operation. [ABSTRACT FROM AUTHOR]

Vanadium dioxide (VO 2) nanocrystalline materials are of great interest as for modern electronics and photonics as well as for energy saving technologies. Nevertheless, there still remains a challenge to realize their controllable synthesis, as evidenced by the low rate of implantation of existing technologies into mass production. Here, a hydrothermal reaction in a water-ethylene glycol (EG) solution has been coupled with the post-deposition annealing, yielding a range of phase-pure vanadium dioxide nanostructures on single-crystal r-sapphire substrate. A directed change in the viscosity of the precursor solution by using a change in the EG : H 2 O ratio makes it possible to control the nucleation rate and thus form VO 2 isolated nanocrystals, as well as their ordered ensembles with regular distribution and uniform films on the substrate. The obtained nanostructures were extensively characterized by Raman spectroscopy, scanning electron microscopy, atomic force microscopy, and transmission electron microscopy combined with energy-dispersive X-ray spectroscopy. Continuous VO 2 nanostructures demonstrated a metal-insulator transition (MIT) with a jump in resistivity of about 103–104, as well as a giant terahertz (THz) modulation depth up to 86 % (in the range from 0.3 to 2.0 THz), which confirms their high-quality and the possibility of their use in the creation of functional electronic and THz optical devices. [ABSTRACT FROM AUTHOR]

Intense electrolyte loss as a result of excessive sweating can disrupt the electrolyte balance in the body and cause damage to many organs, as well as potentially fatal disturbances in even brain functions. There are commercial sensors developed to monitor users' physical activity, however, few of them can provide information on users' health status through sweat analysis. Herein we report a chemiresistive sensor to monitor the sweat electrolyte concentration level. Metal oxide semiconducting CuO films were deposited on Au electrodes as sensing layers. Ca2+ ions were doped into the CuO lattice as sensitizer. Scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and UV–Vis spectroscopy were used to characterize the films. Sensors produced with pure and Ca-doped CuO films were tested against different concentrations of artificial sweat. The sensors responded well to sweat electrolyte concentration with a linear detection range of 20–80 mM. Detection limits between 6.64 and 9.86 mM were estimated using standard deviation methods. Average sensor response times were found to be 12 s. [ABSTRACT FROM AUTHOR]

In this study, the properties of the porous silicon (PS) photodetector were improved by depositing Au@In2O3 (core-shell) nanoparticles on the surface of PS. The Au@In2O3 NPs were prepared using the pulsed laser ablation in liquid (PLAL) technique at different laser energies of 500, 700, and 900 mJ, using a Nd:YAG laser with a wavelength of 1064 nm. The PS was prepared using the electrochemical etching (ECE) method, with an etching current density of 20 mA/cm2, an etching time of 15 min, and a hydrofluoric acid concentration of 25%. Structural, morphological, optical, and electrical measurements of the PS, Au@In2O3 NPs, and Au@In2O3 NPs/PS were conducted using the X-ray diffraction (XRD) test, field-emission scanning electron microscopy (FE-SEM) analysis, photoluminescence (PL), and UV-vis spectroscopy showed the highest peak of absorbance at 327–385 nm, and the photoluminescence (PL) peak of Au@In2O3 NPs was in the visible range show broad band and splitting for 399.5 nm for In2O3 NPs and 469 nm for Au NPs, while the PS peak was at about 561.8 nm. As a result, the photodetectors device system exhibited high responsivity (Rλ) and quantum efficiency in the visible area, the higher responsivity of the Au@In2O3 NPs/PS photodetector was measured as 0.1450 A/W for specimens prepared at a laser energy of 500 mJ/pulse. [ABSTRACT FROM AUTHOR]

The work reported here deals with fabricating iron oxide nanoparticles incorporated polyvinyl alcohol nanocomposite films via the solution‐casting green route, characterized using various characterization techniques. X‐ray diffraction analysis shows interaction of nanoparticles with the polyvinyl alcohol matrix, scanning electron microscopy shows surface morphology of crack‐free films, energy dispersive spectroscopy indicates elemental purity, tensiometer analysis shows changing behavior of hydrophilic to hydrophobic, thermogravimetric analysis shows improved thermal stability, ultraviolet‐visible spectroscopy shows tunable optical properties, and frequency response analysis shows improved electrical properties. A small incorporation (1 wt. %) of iron oxide nanoparticles has induced significant alternations in structural, wetting, thermal, optical, and electrical properties of the polyvinyl alcohol‐based nanocomposite films. Results showed notable changes in the structural phases, water contact angle (39.5° to 97.7°), optical absorption edge (5.12 eV to 4.84 eV), indirect band gap (4.99 eV to 4.68 eV), direct bandgap (5.41 eV to 5.21 eV), and band tail (0.57 eV to 0.89 eV) from native polyvinyl alcohol to polyvinyl alcohol/iron oxide nanocomposite films. Enhancements were observed in refractive indices, optical conductivity, optical dielectric loss, thermal stability, dielectric constant, and dielectric loss on incorporating iron oxide nanoparticles into the polyvinyl alcohol matrix. The fabricated nanocomposite films might be a potential material for optoelectronic and microelectronics applications. [ABSTRACT FROM AUTHOR]

Kesterite-based copper zinc tin sulfide (CZTS) and copper zinc tin selenide (CZTSe) thin films have attracted considerable attention as promising materials for sustainable and cost-effective thin-film solar cells. However, the successful integration of these materials into photovoltaic devices is hindered by the coexistence of secondary phases, which can significantly affect device performance and stability. This review article provides a comprehensive overview of recent progress and challenges in controlling secondary phases in kesterite CZTS and CZTSe thin films. Drawing from relevant studies, we discuss state-of-the-art strategies and techniques employed to mitigate the formation of secondary phases. These include a range of deposition methods, such as electrodeposition, sol-gel, spray pyrolysis, evaporation, pulsed laser deposition, and sputtering, each presenting distinct benefits in enhancing phase purity. This study highlights the importance of employing various characterization techniques, such as X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, for the precise identification of secondary phases in CZTS and CZTSe thin films. Furthermore, the review discusses innovative strategies and techniques aimed at mitigating the occurrence of secondary phases, including process optimization, compositional tuning, and post-deposition treatments. These approaches offer promising avenues for enhancing the purity and performance of kesterite-based thin-film solar cells. Challenges and open questions in this field are addressed, and potential future research directions are proposed. By comprehensively analyzing recent advancements, this review contributes to a deeper understanding of secondary phase-related issues in kesterite CZT(S/Se) thin films, paving the way for enhanced performance and commercial viability of thin-film solar cell technologies. [ABSTRACT FROM AUTHOR]

Spherical BiOI/UiO-66(Zr) composite materials were synthesized using a solvothermal method. The compositions, structures, and optical properties of the materials were characterized through X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer–Emmett–Teller measurements, and UV-Vis spectroscopy. The experimental investigation involved the activation of persulfate (PMS) by BiOI/UiO-66(Zr) for the visible light degradation of Acid Orange II. The effects of the BiOI to UiO-66(Zr) mass ratio, BiOI/UiO-66(Zr) dosage, PMS concentration, Acid Orange II concentration, pH, and inorganic anion species on the degradation system were explored. BiOI/UiO-66(Zr) exhibited excellent visible light responsiveness. Under the optimal conditions (BiOI to UiO-66(Zr) mass ratio of 1 : 0.3, BiOI/UiO-66(Zr) dosage of 300 mg L−1, 0.3 mmol L−1 PMS, 100 mg L−1 Acid Orange II, 25 °C, and pH 7.0), the degradation efficiency reached 98.5%. While HCO3− and CO32− significantly influenced the reaction system, NO3−, Cl−, and SO42− had minimal impact. The reaction process followed a first-order kinetic model. Mechanistic analysis indicated that efficient transfer of holes and electrons between BiOI and UiO-66(Zr) occurred during the degradation, enhancing the separation efficiency of photo-generated electron–hole pairs. The ˙O2− and 1O2 generated in the reaction system played a crucial role in photocatalytic degradation of Acid Orange II, with ˙OH, SO4−˙, and h+ acting as auxiliary agents. The degradation process was a result of the synergistic action of various reactive radicals. Repetitive photocatalysis experiments demonstrated that the BiOI/UiO-66(Zr) composite exhibited excellent stability, with minimal reduction in degradation efficiency after four cycles. [ABSTRACT FROM AUTHOR]

To contribute to the development of sustainable and effective nano‐catalyst for dye degradation is greatly enviable to solve the global environmental remediation problems. In this regard, here facile Co3O4NiOPdOPd nanomaterial was synthesized via phyto‐organic fuel and scrutinized as nanocatalyst to degrade methyl orange (MO). The Co3O4NiOPdOPd nanomaterial was synthesized following the sol gel synthesis methodology using foliar phyto extract of Abies pindrow Royle leaves. The synthesized nanomaterial of Co3O4NiOPdOPd was studied by X‐rays diffraction, Raman spectroscopy, Energy‐dispersive spectroscopy, as well as Field‐emission scanning electron microscopy. Fourier transform infrared spectroscopy, Gas chromatography and Mass spectrometry. The facile bio nanomaterial was studied for removal of MO both under sunlight and under dark. Fabricated nanocatalyst of mixed metal oxides (MMO) exhibited the degradation efficiency of 95 % in the presence of sunlight and 85 % without sunlight (in dark condition) in 15 minutes.The comparison of catalytic potential of MOD‐L and MOD‐D for Co3O4−NiO−PdO−Pd for 2 minutes exhibited maximum degradation percent MOD‐L (72.2.4 %) followed by MOD‐D (51.5 %). However, after 20 minutes MOD‐L exhibited higher percentage of 95.4 % while MOD‐D revealed 84.8 percent degraded MO. Consequently, the nano‐scale features have enhanced the catalytic performance of Co3O4NiOPdOPd photocatalyst towards water purification from organic pollutants. [ABSTRACT FROM AUTHOR]

Selenium nanoparticles have drawn interest recently, due to their distinctive physicochemical characteristics and potential usage in numerous applications, including medicine, electronics and catalysis. In this study, we employed Biancaea sappan (BS), often known as sappan wood or Brazilwood, which is a flowering tree that is endemic to Southeast Asia. Due to its antioxidant, anti-inflammatory and anticancer properties, this tree's heartwood is frequently used in traditional medicine. Additionally, the wood is used to make natural dyes. In this study, we aim to develop an ecofriendly selenium nanoparticle using BS , as a natural reducing agent and curcumin as a capping agent. The nanoparticles were synthesized using the green synthesis method and characterized using various techniques. Biocompatibility was evaluated using hemolytic assay and the bioactivity of the nanoparticles was assessed using anti-inflammatory and antioxidant assays. Selenium nanoparticles (BCSeN) were successfully synthesized using BS bark extract and functionalized with curcumin. The nanoparticles were characterized by UV-Vis Spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy and Energy-dispersive X-ray spectroscopy (EDX) analysis, confirming their morphology, crystallinity, functionalization, elemental composition, size and stability. In vitro, bioactivity studies revealed that the BCSeN exhibited significant anti-inflammatory activity. They also demonstrated notable antioxidant efficacy against DPPH (2,2-diphenyl-1-picrylhydrazyl) and were also found to have minimal hemolytic potential. Our findings highlight the potential of BCSeN as a promising candidate for anti-inflammatory and antioxidant applications. However, further in-depth analysis is required to fully understand their efficacy and toxicity. [ABSTRACT FROM AUTHOR]

The Yungang Grottoes, excavated during the 5th to 6th centuries AD, stand as a pinnacle of Buddhist sculpture, representing a precious world cultural heritage. Since their excavation, the grottoes have undergone multiple phases of painting, with a significant amount of pigment still present on the surfaces of the stone carvings. Since the 1990s, two large-scale archaeological excavations have been conducted on both the front ground and the summit of Yungang Grottoes. During these excavations, various artifacts with accompanying pigments were unearthed, encompassing stone carvings, grinding tools, architectural components, fragments of murals, and remnants of clay sculptures, spanning the historical periods of the Northern Wei, Liao-Jin, and Ming-Qing dynasties. Using portable X-ray fluorescence spectrometry, portable microscopy, polarizing microscopy, scanning electron microscopy–energy dispersive X-ray spectroscopy, and confocal Raman microscopy, we conducted a comprehensive analysis of these painted elements. The investigation revealed the presence of hematite, vermilion, goethite, malachite, calcium carbonate, lead white, and ivory black pigments in the Northern Wei samples. The Liao-Jin samples exhibited hematite, while the Ming-Qing samples contained vermilion, minium, atacamite, lead white, and Prussian blue. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) exhibit structural flexibility induced by temperature and guest adsorption, as demonstrated in the structural breathing transition in certain MOFs between narrow-pore and large-pore phases. Soft modes were suggested to entropically drive such pore breathing through enhanced vibrational dynamics at high temperatures. In this work, oxygen K-edge resonant X-ray emission spectroscopy of the MIL-53(Al) MOF was performed to selectively probe the electronic perturbation accompanying pore breathing dynamics at the ligand carboxyl­ate site for metal-ligand interaction. It was observed that the temperature-induced vibrational dynamics involves switching occupancy between antisymmetric and symmetric configurations of the carboxylate oxygen lone pair orbitals, through which electron density around carboxylate oxygen sites is redistributed and metal-ligand interactions are tuned. In turn, water adsorption involves an additional perturbation of π orbitals not observed in the structural change solely induced by temperature. [ABSTRACT FROM AUTHOR]

The X-ray emission spectrometer at SPring-8 BL07LSU has recently been upgraded with advanced modifications that enable the rotation of the spectrometer with respect to the scattering angle. This major upgrade allows the scattering angle to be flexibly changed within the range of 45-135°, which considerably simplifies the measurement of angle-resolved X-ray emission spectroscopy. To accomplish the rotation system, a sophisticated sample chamber and a highly precise spectrometer rotation mechanism have been developed. The sample chamber has a specially designed combination of three rotary stages that can smoothly move the connection flange along the wide scattering angle without breaking the vacuum. In addition, the spectrometer is rotated by sliding on a flat metal surface, ensuring exceptionally high accuracy in rotation and eliminating the need for any further adjustments during rotation. A control system that integrates the sample chamber and rotation mechanism to automate the measurement of angle-resolved X-ray emission spectroscopy has also been developed. This automation substantially streamlines the process of measuring angle-resolved spectra, making it far easier than ever before. Furthermore, the upgraded X-ray emission spectrometer can now also be utilized in diffraction experiments, providing even greater versatility to our research capabilities. [ABSTRACT FROM AUTHOR]

In the present investigation, pure and different concentrations (2%, 4%, 6%, 10%) of Ag-doped Co3O4 nanoparticles have been synthesized by the sonochemical method and subsequent calcination at different high temperatures. Structural, optical, morphological properties and elemental composition of synthesized nanoparticles have been characterized using X-ray diffraction, UV–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. According to X-ray diffraction results, no peaks related to silver or silver oxide were observed in the diffractograms of doped samples. Blue shift was observed in the absorption curve of Ag-doped Co3O4 nanoparticles compared to undoped Co3O4 nanoparticles. From transmission electron microscopy measurements, 2%, 4% and 6% Ag-doped Co3O4 nanoparticles thermal annealed at 500 °C exhibit sphere-like and irregularly structured morphology, while 10% Ag-doped Co3O4 nanoparticles have a rhombohedral-like, hexagonal and spherical morphology. The dielectric constant value (ɛʹ) was found to decrease with increasing frequency and it can be explained by Maxwell–Wagner model. The value of the dielectric constant increased with increasing of temperature from 25 to 100 °C and the highest value was observed for Ag0.1Co2.9O4/PVA sample at 100 °C temperature. [ABSTRACT FROM AUTHOR]

This research investigates the optical, structural, electrical, and photoelectrochemical characteristics of CdS/CdSe heterojunctions formed on both ITO and p–Si substrates. The deposition of CdS and CdSe films was carried out using the chemical bath deposition method, which is economical and simple method. The optical, structural, and electrical properties of CdS/CdSe heterojunctions were analyzed through UV–Vis spectrometry, photoluminescence (PL) spectroscopy, field emission–scanning electron microscopy (FE‐SEM), X‐ray diffraction (XRD), Raman spectroscopy, and Hall‐effect measurements. Furthermore, Mott–Schottky analysis was employed to investigate the electrochemical properties of the semiconductor CdS/CdSe heterojunctions on both ITO and p–Si substrates. Additionally, the photoelectrochemical investigations of CdS/CdSe heterojunctions on ITO and p–Si substrates were conducted by electrochemical analyses using linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), and photocurrent – time plots under both dark and illuminated conditions. [ABSTRACT FROM AUTHOR]

The interaction of fullerenes and their derivatives with environmental molecules such as oxygen or water was crucial for the rational design of low-dimensional materials and devices. In this paper, the near-edge X-ray absorption fine structure (NEXAFS), X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) shake-up satellites were employed to distinguish the oxides and hydrates of the fullerene C60 and azafullerene C59N families. The study includes various isomers, such as the open [5,6] and closed [6,6] isomers of C60O, C60H(OH), C60-O-C60, C60H-O-C60H, C59N(OH) and C59N-O-C59N, based on density functional theory. These soft X-ray spectra offered comprehensive insights into the molecular orbitals of these azafullerene molecular groups. The oxygen K-edge NEXAFS, carbon and oxygen K-edge XPS shake-up satellite spectra provided valuable tools for distinguishing oxides or hydrates of fullerene C60 and azafullerene C59N. Our findings could significantly benefit the development of fullerene functional molecular materials and expand the application scope of soft X-ray spectroscopy as a molecular fingerprinting tool for the fullerene family. [ABSTRACT FROM AUTHOR]

The study presented here applied various analytical techniques to examine a small fragmented painted gypsum plaster with heart motifs discovered at the Sasanian site of Vigol, Central Iran, to identify the materials used to produce the plaster. The plaster and its paint layer were analysed by X-ray fluorescence, X-ray diffraction, optical microscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy and micro-Raman spectroscopy methods. The results revealed that the plaster layer is made of gypsum with some impurities—mainly soil minerals—with the concentration of these impurities being less at the surface of the plaster. It was also discovered that the heart motifs were painted using minium red lead pigment. As the main damage to the plaster is fragmentation, conservation included joining the fragments and consolidating the surface of the plaster. Finally, a preservation box using transparent polycarbonate plates was designed and manufactured for the display and handling of the newly restored plaster. [ABSTRACT FROM AUTHOR]

In this paper, the effect of Nd-YAG laser irradiation with the wavelength of 1064 nm on the formation of micro and nanostructures on the surface of stainless steel and its influence on the bacterial adhesion is investigated. Field Emission scanning electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy and sessile drop method were used to investigate the irradiated sample morphology, topography, chemical modifications and wetting properties, respectively. Finally, the bacterial adhesion test was done on irradiated and non-irradiated surfaces. The results show that formation of dense microstructures with nano roughness on the surface following laser irradiation at a fluence above the ablation threshold, leads to antibacterial properties of the sample. [ABSTRACT FROM AUTHOR]

By controlling the release of encapsulated antibacterial materials and the intrinsic antibacterial components of metal–organic frameworks (MOFs) through the slow degradation of their frameworks, the composite material that contains self‐degrading MOFs demonstrates synergistic antibacterial effects. In this study, MIL‐53(Fe) was investigated for finding MOFs that have metal oxides in the pores ([CuO]1.3@MIL‐53(Fe) and [ZnO]1.05@MIL‐53(Fe)) with antibacterial activity. MIL‐53(Fe) exhibits a significant surface area and precise pore structure, so it was a good choice for this study. MIL‐53(Fe) was synthesized by solvothermal method, and [Cu (CH3COO)2.H2O]1.0@MIL‐53(Fe) and [Zn (CH3COO)2.2H2O]0.5@MIL‐53(Fe) were prepared by immersion of the MOF in aqueous solution of [Cu (CH3COO)2.H2O] and [Zn (CH3COO)2.2H2O], respectively. Then, the [MO]x@MIL‐53(Fe) nanocomposites were prepared by thermal treatment of [Cu (CH3COO)2.H2O]1.0@MIL‐53(Fe) and [Zn (CH3COO)2.2H2O]0.5@MIL‐53(Fe) at 310°C and 290°C in N2 atmosphere, respectively. Fourier Transform Infrared Spectrometer, X‐ray powder diffraction, inductively coupled plasma–Optical Emission Spectrometry, Field Emission Scanning Electron Microscope, energy‐dispersive spectrometer‐mapping, and thermogravimetric analysis analyses were proved the successful synthesis of these compounds. Finally, the antibacterial activity of the composites was assessed against both Gram‐positive bacteria (Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli). [ABSTRACT FROM AUTHOR]

Precise control and characterization of nanomaterials at working conditions are essential for further rational applications in many areas important for modern society. Penetrating properties of X-ray radiation in combination with advanced spectroscopy schemes are an ideal tool to investigate modifications of nanomaterials with extraordinary precision. Here, we present preliminary results on the controlled oxidation of copper nanoparticles and exploration of X-ray absorption spectroscopy to follow electronic and structural changes. The described pilot experiment raises questions on the applicability of high energy resolution X-ray detection schemes in potential future investigations aimed at following reversible reduction/oxidation processes at nanoparticle surfaces. [ABSTRACT FROM AUTHOR]

The present research reports an experimental study of Ni-W-P-nanoTiO2 composite coatings deposited on API X60 low-carbon steel by the electroless method. Electroless bath parameters are optimized to attain maximum deposition rate using the Taguchi design (L9 orthogonal array). Analysis of variance was performed to find out the significance of individual parameters. A confirmation test was performed at the initial and optimal parameter combination obtained from the Taguchi analysis. In addition, the applicability of artificial neural network (ANN) was also examined for the prediction of deposition rate. An ANN 4-7-1 network accurately predicted the deposition rate with a correlation coefficient (R2) valued at 0.9820. Atomic force microscopy and field emission scanning electron microscopy were used to characterize the surface morphology, and energy-dispersive spectroscopy, and X-ray diffraction were used for compositional and phase study of the coatings. The corrosion behavior of nanocomposite coatings was tested in 3.5 wt% NaCl solution by potentiodynamic polarization. The optimum combination was achieved with 24 g/L of reducing agent content, 10 g/L of TiO2 nanoparticles content, bath pH of 9, and a temperature of 80 °C. [ABSTRACT FROM AUTHOR]

The addition of Ca2MgSi2O7 to CaSiO3 bioceramics was investigated in order to modify the dissolution rate of CaSiO3. A series of CaSiO3–xCa2MgSi2O7 composite ceramics with x values of 2, 5, 10, and 20 wt% have been successfully obtained. The effects of Ca2MgSi2O7 addition on CaSiO3–Ca2MgSi2O7 ceramics degradation behavior and apatite formation were comprehensively investigated by means of X-ray diffraction (XRD), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), Fourier transform infrared spectroscopy (FTIR), and inductively coupled plasma optical emission spectrometry (ICP-OES). The results showed that the dissolution rate of the achieve system ceramics gradually decreased in succession, and the apatite-forming was delayed by the addition of Ca2MgSi2O7. The suitable dissolution rate and apatite-forming ability of CaSiO3–Ca2MgSi2O7 bioceramics can be expected, indicating that the addition of Ca2MgSi2O7 to CaSiO3 bioceramics may be a promising route for modifying the dissolution behavior and apatite-forming ability of CaSiO3 bioceramics. [ABSTRACT FROM AUTHOR]

A gas sensor utilizing V2O5/Pd thin films has been successfully created by pulse laser deposition on porous silicon substrate, demonstrating rapid response times and superior sensitivity for detecting gases at low temperatures. The investigation of sensor response, selectivity, and stability demonstrates the impressive sensing capabilities of the thin films. Vanadium pentoxide films doped with palladium (V2O5/Pd) are fabricated through pulsed laser deposition technique, with varying laser pulse energy (600, 800, and 1000) mJ/pulse, for the purpose of sensing applications related to Hydrogen Sulfide (H2S) and Nitrogen Dioxide (NO2). The ablation procedure entails the utilization of a Q-switched Nd:YAG laser that operates at a specific wavelength of 1064 nm. The laser system exhibits pulse duration of 10 ns and a repetition rate of 1 Hz when operating on a porous silicon n-type Si (111) substrate. The X-ray diffraction, UV–Vis Spectroscopy, Raman scattering, Photoluminescence spectroscopy, and field emission-scanning electron microscopy techniques were employed to investigate the crystal structure, optical structure, and morphological properties of the V2O5/Pd NPs. As the energy of the pulse laser grows, the presence of well-defined peaks in the V2O5/Pd thin film indicates an enhancement in its crystalline structure. The size of the surface grains exhibit an augmentation, accompanied by an increase in the energy gap, leading to an elevated level of homogeneity. This study aimed to evaluate the influence of Pd on the development kinetics of vanadium pentoxide nanoparticles. The findings of this investigation demonstrated that the addition of Pd resulted in several notable effects, including improved sensitivity, reduced operational temperature requirements, and the capacity to maintain high sensitivity levels even at room temperature. [ABSTRACT FROM AUTHOR]