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A high detection efficiency thermal neutron detector based on the 6LiF/ZnS(Ag) scintillation screens, wavelength-shifting fibers (WLSF) and Silicon photomultiplier (SiPM) readout is under development at China Spallation Neutron Source (CSNS) for the Engineering Material Diffractometer (EMD).A prototype with a sensitive volume of 180mm×192mm has been built. Signals from SiPMs are processed by the self-design Application Specific Integrated Circuit (ASIC). The performances of this detector prototype are as follows: neutron detection efficiency could reach 50.5% at 1 A, position resolution of 3, the dark count rate 200KHz. Such detector prototype could be an elementary unit for applications in the EMD detector arrays.

With great superiorities in energy density, rate capability and structural stability, Na3V2(PO4)2F3 (NVPF) has attracted much attentions as cathode of sodium ion battery (SIB), but it also faces challenges on its poor intrinsic electronic conductivity and the controversial de/sodiation mechanism. Herein, a series of Zr-doped NVPF coated by N-doped carbon layer (~5 nm in thickness, homogenously) materials are fabricated by a sol–gel method, and the optimized heteroatom-doping amounts of Zr and N doping improve intrinsic properties on enlarging lattice distance and enhancing electronic conductivity, respectively. Specifically, among all samples of Na3V2−xZrx(PO4)2F3/NC (NVPF-Zr-x/NC, x = 0, 0.01, 0.02, 0.05, and 0.1), the optimized electrode of NVPF-Zr-0.02/NC delivers high reversible capacities (119.2 mAh g−1 at 0.5 C), superior rate capability (98.1 mA h g−1 at 20 C) and excellent cycling performance. The structural evolution of NVPF-Zr-0.02/NC electrode, in-situ monitored by X-ray diffractometer, follows a step-wise Na-extraction/intercalation mechanism with reversible multi-phase changes, not just a solid-solution-reaction one. Full cells of NVPF-Zr-0.02/NC//hard carbon demonstrate high capacity (99.8 mA h g−1 at 0.5 C), high out-put voltage (3.5 V) and good cycling stability. This work is favorable to accelerate the development of high-performance cathode materials and explore possible redox reaction mechanisms of SIBs.

Hot mix asphalt (HMA) is the most of the popular pavement in Malaysia and most economical materials available. Besides that, this pavement type also very suitable with this country climate but HMA need frequency rehabilitation and maintenance due the damages caused by traffic load. In ways to minimize the damage and increase the services life of pavement, modification of asphalt binder is one of the approaches to improve pavement performance and services life. HMA can be modified with many types of fibre including natural fibre. This study utilises the usage of natural fibre as modifier of porous asphalt. The performance of modified porous asphalt is assessed by microstructure analysis. Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Fourier Transform Infrared Spectrophotometer (FTIR), Powder X-ray Diffractometer (XRD), and Permanence Deformation Resistance are some of the laboratory results that have been used. The characteristics of PA modification with 0.3% kenaf fibre are demonstrated in this research. In the interior structure of PA, kenaf fiber diffuses effectively. C and Ca elements contributed the most in the experiment, as did the element and chemical content of PA modified with kenaf fiber. In comparison to the control specimen, changed PA has more persistent deformation and PA with 0.6% kenaf fiber had the greatest resilient modulus value. From the results, it displays that the addition of natural fibre is able to enhance the performance of porous asphalt. This study also promotes the sustainable building materials especially in pavement construction.

The presented work utilizes the chemical bath deposition technique to fabricate zinc oxide nano-thin films on a glass substrate. The quality of synthesized films is dependent on the deposition parameters, which include the solvents and metal salts used, as well as the bathing time and temperature. The impact of the pH value of the solution on the crystal structure, surface morphological, and optical characteristics of zinc oxide thin films was studied in this respect. An XRD diffractometer was used to determine the structural characteristics; a scanning electron microscope was utilized to analyze the surface topology. The linear optical properties were carried out using a UV–VIS spectrometer. The XRD results showed an increase in grain size from 36.06 nm to 42.23 nm as the pH value increased from 8 to 10. The Debye-Scherrer method was utilized to assess crystal grain size and microstrain along (1 0 1) orientation. SEM images showed a significant correlation between grain size distribution and precursor’s solution pH. All the deposited films have shown more than 86% optical transparency, suggesting that these obtained films are best suitable for transparent conducting electrodes for display devices. However, the optical transparency of the deposited films has decreased with an increase in pH value, which may be attributed to increased film thickness. The sample deposited at pH: 10 exhibited the minimal optical bandgap of all the samples.

Excellent electrical properties and the improved long-term stability of ZnO varistor ceramics were simultaneously achieved by doping NiO. The microstructural features were investigated using X-ray diffractometer, scanning electron microscopy, and energy dispersive spectroscopy, while the intrinsic point defects were characterized using frequency domain dielectric spectroscopy and verified by photoluminescence and Raman spectra. The results indicated that in the ZnO varistor ceramics, a reverse manipulation of donor point defects, i.e., suppressing mobile zinc interstitial but increasing stable oxygen vacancy, was achieved. The long-term stability of NiO-doped ZnO ceramics was improved via a decrease in zinc interstitial density, with a degradation rate of 0.064 μA cm−2 h−0.5. Meanwhile, due to an increase in oxygen vacancy density, the excellent nonlinear current–voltage performance, i.e., a high nonlinear coefficient (72.9), low leakage current density (0.08 μA cm−2), and low grain resistivity (13.43 × 10−3 Ω m), was maintained. The findings of this study provide a possible method for developing high-performance ZnO varistor ceramics by manipulating point defects.

In this work, the eucalyptus and teak leave extracts are used as natural dyes for dye-sensitized solar cells (DSSCs). The TiO2, copper doped -TiO2 (Cu-TiO2), and nitrogen doped-TiO2 (N-TiO2) nanoparticles were synthesized by using the sol–gel method. The structural, morphological and elemental properties of the prepared samples were tested by X-ray diffractometer (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). XRD revealed the anatase-TiO2 phase and calculated crystallite sizes are 10, 11.23, and 13.97 nm, correspondingly. SEM micrograph shows the spherical shaped nanoparticles with less agglomeration and primary elements (Ti, O, Cu, N) confirmed by EDS spectra. Further, the nanoparticles used as a photoanode in DSSC device with natural dyes and studied their performance.

The Co-precipitation method (CPM) was used to make pure and Fe doped Zinc Oxide (ZnO) nanoparticles (Nps) in this study. X-ray diffractometer (XRD), UV–vis absorption spectroscopy and Fourier transform infrared spectroscopy (FTIR) were used to describe the sample's structural, optical, and electrical properties. The hexagonal wurtzite structure of ZnO was verified by the X-ray diffraction pattern. The Debye Scherrer formula was used to measure the average crystallite size. The pure and Fe doped ZnO sample absorbs the radiations in the UV ranges up to 327.27, 324.74 and 323.5 nm and almost all the visible spectrum radiations are transmitted by the synthesized Nps. FTIR analysis was used to identify the functional frequencies of pure and Fe doped ZnO Np. The electrical conductivity of ZnO Nps decreases with Fe doping concentration due to increase in deep donor concentration.

The advanced process of recovering the trapped oil from the reservoir is known as Enhanced Oil Recovery (EOR), which involves the injection of foreign fluids to manipulate the reservoir’s petrophysical properties. Nanoparticles in this regard have shown significant effects on various EOR parameters, such as interfacial tension and sweep efficiency. However, the composites of different nanoparticles have been reported to have shown exceptional effects over bare single nanoparticles (NPs) because of the synergy actions concerning measures of improving their rheological properties. In this work, Zinc oxide/Silicon dioxide (ZnO/SiO2) nanocomposites were synthesized via a Sol-gel method and annealed at different temperatures (400 and 600°C). The chemical interaction, crystal structures, morphology, and composite formation were studied via Fourier-Transform Infrared Spectroscopy (FTIR), X-Ray diffractometer (XRD), Field Emission Scanning Electron Microscopy (FESEM), and Energy dispersed X-ray (EDX) respectively. The result shows that the chemical interactions between the ZnO and amorphous SiO2 were confirmed by the presence of the characteristic functional group bands, and the establishment of the chemical bond in Zn–O, and Si–O on the surface of the composite materials. From the XRD analyses, the crystal size of the ZnO/SiO2 composite materials significantly increased with an increase in temperature whereas the morphological size undergoes a reduction by increasing temperature as shown by FESEM. The rheological property (viscosity) of the ZnO/SiO2 nanocomposites was investigated and the outcome has revealed that the viscosity of the composite material increases with an increase in annealing temperature which consequently could serve as a basis to overcome the viscous fingering and facilitates the oil displacements in EOR.

Titanium di-oxide (TiO2) multilayer thin films were deposited on glass substrates by using sol–gel spin-coating technique. The TiO2 thin film coatings were varied from two- to six layers and each layers calcinated at 600°C for 1 hour. The prepared samples were characterized by UV–visible spectrophotometer (UV–Vis), Fourier transform infra-red (FTIR) spectroscopy and X-ray diffractometer (XRD) techniques. The UV–Vis spectra showed the highest reflectance with the effect of six (6L) layers of TiO2 thin films as compared to the two- (2L) and four (4L) layers of thin films. The XRD patterns revealed the anatase-TiO2 phase with six layers of TiO2 and amorphous-TiO2 nature confirmed by two and four layered films. The obtained results proved that the use of enhanced multilayers (6L) of TiO2 thin films were effectively improved the quality of film crystallinity (8.3 nm) and corresponding optical performance as compared to reduced layers.

The crystallization of active pharmaceutical ingredients (APIs) in matrix-type transdermal patches has implications for the rate of drug absorption through the skin and patch adhesion strength. Therefore, the presence or absence and the degree of API crystallinity must be controlled to guarantee the quality of patches. In this study, the utility of laboratory-level X-ray diffractometers for the detection and analysis of crystalline APIs in transdermal patches was investigated using medical patches of tulobuterol and isosorbide dinitrate. Several matrix-type patches employ a controlled drug delivery system containing intentionally crystallized API. Both benchtop and high-resolution laboratory X-ray diffractometers can detect several characteristic peaks of the APIs in these patches even if the patches are wrapped in an outer bag, although a benchtop model provides peak heights one-seventh to one-fifth that of a high-resolution instrument. An isosorbide dinitrate patch containing an unintentionally crystallized spot was wrapped in an outer bag, followed by measurements using both X-ray diffractometers. For both instruments, several isosorbide dinitrate-derived peaks were detected only at the crystallized spot, although the signal-to-noise ratio was poorer for the benchtop model. These results show that a high-resolution X-ray diffractometer is advantageous for high-detection sensitivity and offers a high degree of freedom of the measurement position on the sample. It was concluded that a laboratory-level high-resolution X-ray diffractometer can be used to examine the crystalline state of APIs in patches inside an unopened outer bag.

Carbon nanofibers (CNFs) thin films were prepared by using Radio frequency assisted plasma enhanced chemical vapor deposition (RF-PECVD) technique. Nickel thin films have been used for preparation of CNFs thin films, which stimulates the growth. The identification and confirmation of the graphitic phase of CNFs thin films were confirmed by using X-Ray Diffractometer. Nanostructure surface morphology of the CNFs thin films have been investigated by an Atomic Force Microscope, which reveals that the typical diameter of the CNFs was ∼ 180 nm with length of several micrometers. The electron field emission properties of CNFs thin films have been carried out for different cathode–anode separation and for various ambient temperatures. It was observed that with the extent of cathode–anode separation from 70 to 210 μm, the turn-on field was reduced to 3.5 V/μm from 4.4 V/μm respectively. Temperature dependent electron field emission measurement showed that the turn-on field was reduced to 2.3 V/μm from 4.2 V/μm, as ambient temperature of CNFs thin films was increased from 30 °C to 250 °C respectively. The field enhancement factor and turn-on field were calculated and demonstrate the electron emission procedure.

An agricultural waste, palm oil fuel ash (POFA) has been evaluated as a Ni catalyst support for the methane decomposition process. The effects of solvent and pre-treatment technique during the POFA pre-treatment have been investigated towards the catalytic performance of Ni supported on POFA (Ni-POFA) catalyst prepared at 10 wt% Ni loading. Methane decomposition of Ni-POFA catalyst was carried out at 550 °C for 6 hrs. The POFA and Ni-POFA were characterized using X-ray fluorescence (XRF), X-ray diffractometer (XRD), N2 adsorption–desorption isotherms and field emission scanning electron spectroscopy (FESEM). The results showed that citric acid solution was the best solvent for POFA pre-treatment. The SiO2 content in the POFA pre-treatment improved from 42.4 to 72 wt%. Good CH4 conversion achieved by Ni-POFA catalyst in the methane decomposition was attributed to high SiO2 in the POFA treated with citric acid. Compared to conventional stirring, pre-treatment of POFA with ultra-sonication technique has produced POFA support with smaller particles size, and Ni-POFA catalyst with better BET surface area and better Ni dispersion. These catalyst properties have contributed to an exceptional catalytic performance of 71% of initial CH4 conversion and 4.2% of initial H2 yield of Ni-POFA catalyst in the methane decomposition. The work suggests that POFA has the potential to be utilized as catalyst support, and pre-treatment is crucial for a reasonable catalytic performance in methane decomposition.

This paper presents synthesis and study of Structural, Optical, and Photocatalytic properties of bismuth ferrite (BFO) and nickel doped bismuth ferrite (BiFe1-xNixO3) nanoparticles. The synthesis of BiFeO3 and BiFe1-xNixO3 (x = 0.02, 0.04) are done by Sol-Gel method. After synthesis the samples of pure and transition metal ion (Ni) doped bismuth ferrite have been studied by using X-ray diffractometer (XRD), X-ray Photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscope and Raman Spectroscopy. Optical properties are studied by using UV–vis spectroscopy using different wavelengths (range 300–800 nm). Photocatalytic properties are also studied by degradation of MB dye using prepared samples as photocatalyst. XRD patterns shows that all the prepared samples are crystalline and crystallinity increased by Ni-doping and shifts in XRD peaks by Ni-doping shows the distortion in the structure of BFO. Raman spectroscopy also indicates the rhombohedral distorted structure of Ni-doped BFO in R3C space group. FESEM micrographs shows that Ni-doped BFO has polyhedral and spherical shape grains and Ni doping cause reduction in grain size. Optical band gap reduced due to Ni-doping is shown by the UV–Vis spectroscopy results and Tauc’s plots. The increase in reduction of MB dye due to Ni-doping shows the enhanced photocatalytic properties of BFO by Ni doping.

Recycling of photocatalyst in wastewater treatment is a big challenge. Fixation of photocatalyst on a flexible surface of solid substrates is a promising solution. In this work, copper ferrite (CuFe2O4) particles were loaded onto polydopamine (pDA) pretreated ceramic/polyester fabrics (CPF) via coprecipitation. The CPF not only acts as loading material for CuFe2O4 particles, but also makes this photocatalyst convenient to recycle. The morphology, elemental composition and structure of the as-fabricated CPF/CuFe2O4 were characterized by scanning electron microscope (SEM), Fourier transform Infrared (FT-IR) spectrometer, X-ray photoelectron spectroscopy (XPS) and X-ray diffractometer (XRD). The degradation rate of methylene blue (MB) by the CPF/CuFe2O4 photocatalyst reached to 98.2% under visible light irradiation for 80 min, reflecting the excellent photocatalytic activity of the composites. The CPF/CuFe2O4 demonstrated good photostability and recoverability, indicating its great potential in wastewater treatment. Moreover, the degradation mechanism and possible degradation pathway of MB by CPF/CuFe2O4 photocatalyst were investigated.

The high-resolution Fourier diffractometer (HRFD) operates at the IBR-2 pulsed reactor, on which the correlation method of data registering has been implemented using a fast Fourier chopper and specialized electronics. A wide-aperture ring back-scattering detector for HRFD has been developed. The detector consists of six Z n S ( A g ) / 6 L i F-scintillation rings, each one of which is divided into 12 sections. Main parameters of this detector: covered solid angle 2 θ = ( 133 − 175 ) ∘ ; Ω d ≈ 2.0 sr; average absorption efficiency 85 %, geometric contribution to resolution Δ d / d < 0.0005. The concept of a detector and its data acquisition system are presented.

The morphology evolution of copper powder was studied under various ball-milling experimental conditions, such as low and high rotation speeds and a ball diameter of 1 mm and 10 mm. A scanning electron microscope and X-ray diffractometer were used to analyze the copper powder particle size, morphology, structure, and crystallite size. The effect of ball size on copper powder particle morphology in dry-type milling was studied using a planetary ball mill. Spherical copper powders were obtained by ball milling at a high rotation speed and with a ball diameter of 1 mm. The experimental results suggest that the particle size and morphology can be controlled by changing the milling conditions during the ball milling. Ball motion was simulated by using a three-dimensional discrete-element model to obtain the force, energy, and power of the ball motion in the ball mill for two different ball sizes and low and high rotation speeds.

Due to the inherent moisture instability problem of hybrid lead halide perovskites, polymer additives have to turn out to be a significant research area to enhance the moisture stability of these materials. It has been found that polymer engineering on the absorber layer of solar cells significantly improves chemical stability and overall device performance. This work reports the fabrication of pristine and polyvinylpyrrolidone (PVP) polymer capped methylammonium lead chloride (CH3NH3PbCl3) perovskite film via the electrospinning method. A structural study using an X-ray diffractometer shows a sharp fall in average crystallite size from 66.05 nm to 39.69 nm when PVP is used in the synthesis procedure. A similar trend is also seen in the microscopic analysis, which depicts that the particle size has decreased for PVP added CH3NH3PbCl3 perovskite film in comparison to CH3NH3PbCl3 pristine film. The surface coverage and uniformity of the film is much more in the presence of PVP. It has been noted from energy dispersive X-ray analysis that the oxygen content is ∼16% more in the pure film, i.e. PVP hinders the effect of moisture in perovskite film, which is the prime objective of this work. Moreover, the optical properties have been analyzed using diffuse reflectance mode of UV–Vis-NIR spectroscope. Finally, the use of CH3NH3PbCl3 as the electron transport layer has been demonstrated in Glass/FTO/CH3NH3PbCl3/CH3NH3SnI3/Spiro-OMeTAD/Au structured perovskite solar cell using the SCAPS-1D simulator. The above-mentioned cell exhibits a power conversion efficiency (PCE) of 21.65%, fill factor (FF) of 72.21%, 32.44 mA/cm2 of short circuit current density (Jsc), and 0.924 V open-circuit voltage (Voc).

Sodium lignosulfonate (SLS) as sacrificial agent (SA) was investigated on the effectiveness in reducing Cetyl Trimethyl Ammonium (CTAB) cationic surfactant adsorption. X-Ray diffractometer (XRD), X-Ray fluorescent (XRF), Scanning electron microscopy (SEM), electron dispersive X-Ray (EDX) and Brunauer-Emmet-Teller (BET) were used to characterize the mineralogy, elemental composition and surface area of kaolinite. Fourier transform infrared-attenuated total reflectance (FTIR-ATR) was used to characterized kaolinite and SLS. The adsorption was done by depletion method using Ultraviolet–visible spectroscopy (UV–Vis). Effectiveness as sacrificial agent in mixture and pre-treatment were studied. The underlying mechanism that responsible for the effectiveness of SA were interpreted and examined. Positive outcome shows that SLS as SA manages to reduce CTAB adsorption. The SLS as SA successfully in reducing CTAB adsorption by using pre-treatment method. Effective underlying mechanism involved is SLS as SA adsorbed readily with the cation bridging assistance from the divalent salt and reversed the surface charge by creating a second layer. As high as 50% CTAB reduction had been seen in the experimental work. This study shows that SLS as SA effectively reducing the CTAB adsorption in pre-treatment.

A catalyst with high NO conversion rate and good sulfur resistance is the key to CO-SCR. Herein, the V-doped OMS-2 molecular sieves were successfully synthesized through the hydrothermal method. The resulting catalyst was characterized by X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscope(TEM) and specific surface area analyzer (BET). The results showed that the addition of V increased the average grain size of OMS-2 and the concentration of oxygen vacancies. Meanwhile, V replaced the K site in OMS-2 and participated in the oxidation-reduction reaction together with Mn. Compared with the V0-OMS-2, the NO conversion rate of V0.2-OMS-2 in a sulfur-free environment increased from 60% to 81% at 150 °C and 75%–94% at 300 °C. The NO conversion rate could still maintain as 80% at 300 °C in a sulfur-containing environment.

Metallic nanoparticles are valuable materials and have a range of uses. Nanoparticles synthesized from plant wastes by environment-friendly methods have attracted the attention of researchers in recent years. Also, the advantages of biological resources and synthesis methods are attracting attention. In this study, silver nanoparticles were synthesized from Ananas comosus fruit peels using ecofriendly method steps. The characterization of the particles obtained was determined by using a UV-visible spectrophotometer (UV-Vis.), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction diffractometer (XRD), Fourier scanning electron microscope (FESEM), and transmission electron microscopy (TEM). The nanoparticles showed maximum absorbance at 463 nm, measuring 11.61 in crystal nanosize, and presented spherical in appearance. An antimicrobial activity test was determined with the minimum inhibition concentration (MIC) method. The nanoparticles showed promising inhibitory activity on the Gram-positive and Gram-negative pathogen microorganisms (Escherichia coli ATCC25922, Staphylococcus aureus ATCC29213, Bacillus subtilis ATCC11774, Pseudomonas aeruginosa ATCC27833 bacteria, and Candida albicans yeast) at low concentrations. The cytotoxic and growth inhibitory effects of silver nanoparticles on different cancer cell lines were examined via the MTT assay. © 2021 Ayşe Baran et al.

Epoxy matrix composites reinforced with clay particles were developed by hand lay-up open mould casting technique. The clay used in this study was pulverized and processed into ultrafine particles through the sedimentation process. The composites were developed by blending the epoxy matrix and hardener with various weight fractions of the ultrafine clay particles (2, 4, 6, 8 and 10 wt%) in open test moulds. In order to accomplish a homogeneous blend of the constituents; manual mixing of the blend was carried out for 3 min. The test specimens were left to cure for 24 hours in the moulds and for additional 27 days at room temperature of 27 ± 2 °C and were thereafter detached from the moulds. The developed composites test specimens were subjected to mechanical tests (flexural, tensile and impact) in accordance with ASTM standards and performed at room temperature. Structural characteristics of the clay particles were determined with the aid of an X-ray diffractometer (XRD). The morphologies of the composites were determined using a scanning electron microscope (SEM). There was a progressive enhancement in the mechanical properties of epoxy composites containing 2-6 wt.% ultrafine clay particles while a drastic decrease in the mechanical properties was noticed in the epoxy/clay composites reinforced with 8-10 wt.% ultrafine clay particles. The SEM images revealed homogeneous particles distributions within the epoxy matrix at lower ultrafine clay particles weight fractions (2 wt. % and 6 wt.%).

Lead tin sulphide (Pb-Sn-S) thin films (TFs) were deposited on fluorine-doped tin oxide (FTO) substrates via the electrochemical deposition process using lead (II) nitrate [Pb(NO3)2], tin (II) chloride dehydrate [SnCl2.2H2O] and thiacetamide [C2H5NS] precursors as sources of lead (Pb), tin (Sn) and sulphur (S). The solution of all the compounds was harmonized with a stirrer (magnetic) at 300k. In this study, we reported on the improvements in the properties (structural and optical) of Pb-Sn-S TFs by varying the deposition time. We observed from X-ray diffractometer (XRD) that the prepared material is polycrystalline in nature. UV-Vis measurements were done for the optical characterizations and the band gap values were seen to be increasing from 1.52 to 1.54 eV with deposition time. In addition to this, the absorption coefficient and refractive index were also estimated and discussed.

The pyRS (Python residual stress) analysis software was designed to address the data reduction and analysis needs of the High Intensity Diffractometer for Residual Stress Analysis (HIDRA) user community. pyRS implements frameworks for the calibration and reduction of measured 2D data into intensity versus scattering vector magnitude and subsequent single-peak-fitting analysis to facilitate texture and residual strain/stress analysis. pyRS components are accessible as standalone user interfaces for peak-fitting and stress/strain analysis or as Python scripts. The scripting interface facilitates automated data reduction and peak-fitting analysis using an autoreduction protocol. Details of the implemented functionality are discussed.

A user-friendly Python-based program has been developed to analyze diffuse scattering from single crystals with the reverse Monte Carlo method. The approach allows for refinement of correlated disorder from atomistic supercells with magnetic or structural (occupational and/or displacive) disorder., A user-friendly program has been developed to analyze diffuse scattering from single crystals with the reverse Monte Carlo method. The approach allows for refinement of correlated disorder from atomistic supercells with magnetic or structural (occupational and/or displacive) disorder. The program is written in Python and optimized for performance and efficiency. Refinements of two user cases obtained with legacy neutron-scattering data demonstrate the effectiveness of the approach and the developed program. It is shown with bixbyite, a naturally occurring magnetic mineral, that the calculated three-dimensional spin-pair correlations are resolved with finer real-space resolution compared with the pair distribution function calculated directly from the reciprocal-space pattern. With the triangular lattice Ba3Co2O6(CO3)0.7, refinements of occupational and displacive disorder are combined to extract the one-dimensional intra-chain correlations of carbonate molecules that move toward neighboring vacant sites to accommodate strain induced by electrostatic interactions. The program is packaged with a graphical user interface and extensible to serve the needs of single-crystal diffractometer instruments that collect diffuse-scattering data.

In this study, CuCrO2–CeO2 nanofibers were prepared by the electrospinning method and the influences of different concentrations on the properties of CuCrO2–CeO2 nanofibers were studied. The electrospun fibers were heated at 700 °C for 1 h in a decompression environment of 1.1 Torr to generate the CuCrO2–CeO2 nanofibers. The crystalline phase of the nanofibers was analyzed by X-ray diffractometer, and both main diffraction peaks corresponded to the CuCrO2 and CeO2 planes. Furthermore, the morphology of the fiber surface was identified by field emission scanning electron microscope, transmission electron microscope, and energy-dispersive X-ray spectroscopy. For this study, the diameter of the CuCrO2–CeO2 nanofibers was approximately 70 nm to 90 nm. The optical properties were analyzed by ultraviolet/visible spectrometer, and the surface area was determined by Brunauer Emmett Teller method. The CuCrO2–CeO2 nanofibers had a high specific surface area of 14.28 m2/g. The energy bandgap of the CuCrO2–CeO2 nanofibers was estimated at 2.95 eV to 2.97 eV with various concentrations. The prepared CuCrO2–CeO2 nanofibers are a potential material for photocatalyst studies.

High-pressure single-crystal X-ray and neutron diffraction data for copper(II) sulfate pentahydrate have been collected under precisely the same conditions, using the same sample mounted in a miniature diamond-anvil cell. The data were combined in a joint ‘XN’ structure refinement., Single-crystal X-ray and neutron diffraction data are usually collected using separate samples. This is a disadvantage when the sample is studied at high pressure because it is very difficult to achieve exactly the same pressure in two separate experiments, especially if the neutron data are collected using Laue methods where precise absolute values of the unit-cell dimensions cannot be measured to check how close the pressures are. In this study, diffraction data have been collected under the same conditions on the same sample of copper(II) sulfate pentahydrate, using a conventional laboratory diffractometer and source for the X-ray measurements and the Koala single-crystal Laue diffractometer at the ANSTO facility for the neutron measurements. The sample, of dimensions 0.40 × 0.22 × 0.20 mm3 and held at a pressure of 0.71 GPa, was contained in a miniature Merrill–Bassett diamond-anvil cell. The highly penetrating diffracted neutron beams passing through the metal body of the miniature cell as well as through the diamonds yielded data suitable for structure refinement, and compensated for the low completeness of the X-ray measurements, which was only 24% on account of the triclinic symmetry of the sample and the shading of reciprocal space by the cell. The two data-sets were combined in a single ‘XN’ structure refinement in which all atoms, including H atoms, were refined with anisotropic displacement parameters. The precision of the structural parameters was improved by a factor of up to 50% in the XN refinement compared with refinements using the X-ray or neutron data separately.

Diazepam has been detected in water sources around the world affecting the quality of drinking water. Even in small quantities, recent studies have proven the negative effects of the drug on human body. Since traditional water and sewage treatment do not remove this type of contaminant, it became interesting to evaluate forms to remove them from water sources. A cheap and eco-friendly alternative to remove this drug from the water is through adsorption using the natural clinoptilolite zeolite as an adsorbent. This work goal was to study the characterizations of clinoptilolite, such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometer (XRD), and Fourier transform infrared spectroscopy (FTIR) and analyze the potential of this material as an adsorbent. Kinetic studies and isotherm analysis were performed in batch. The results showed the potential of the natural zeolite to remove the pollutant in an aqueous medium reaching a maximum adsorption capacity of 8.25 mg g−1. The adsorption process followed a pseudo-second-order kinetics indicating that the adsorption was based on a chemisorption process. The isotherms curves shown favorable adsorption and the Langmuir isotherm model fit the experimental data better. Supplementary Information The online version contains supplementary material available at 10.1007/s11356-021-17452-z.

Metal oxide semiconductor (MOS) gas sensors show poor selectivity when exposed to mixed gases. This is a challenge in gas sensors and limits their wide applications. There is no efficient way to detect a specific gas when two homogeneous gases are concurrently exposed to sensing materials. The p-n nanojunction of xSnO2-yCr2O3 nanocomposites (NCs) are prepared and used as sensing materials (x/y shows the Sn/Cr molar ratio in the SnO2-Cr2O3 composite and is marked as SnxCry for simplicity). The gas sensing properties, crystal structure, morphology, and chemical states are characterized by employing an electrochemical workstation, an X-ray diffractometer, a transmission electron microscope, and an X-ray photoelectron spectrometer, respectively. The gas sensing results indicate that SnxCry NCs with x/y greater than 0.07 demonstrate a p-type behavior to both CO and H2, whereas the SnxCry NCs with x/y < 0.07 illustrate an n-type behavior to the aforementioned reduced gases. Interestingly, the SnxCry NCs with x/y = 0.07 show an n-type behavior to H2 but a p-type to CO. The effect of the operating temperature on the opposite sensing response of the fabricated sensors has been investigated. Most importantly, the mechanism of selectivity opposite sensing response is proposed using the aforementioned characterization techniques. This paper proposes a promising strategy to overcome the drawback of low selectivity of this type of sensor.

Background During thermal spray coating, residual strain is formed within the coating and substrates due to thermo-mechanical processes and microstructural phase changes. Objective This paper provides a comprehensive guide to researchers planning to use neutron diffraction technique for thermal spray coatings, and reviews some of these studies. Methods ENGIN-X at the ISIS spallation source is a neutron diffractometer (time-of-flight) dedicated to materials science and engineering with high resolution testing. The focus is on the procedure of using ENGIN-X diffractometer for thermal spray coatings with a view that it can potentially be translated to other diffractometers. Results Number of studies involving neutron diffraction analysis in thermal spray coatings remain limited, partly due to limited number of such strain measurement facilities globally, and partly due to difficulty is applying neutron diffraction analysis to measure residual strain in the thermal spray coating microstructure. Conclusions This technique can provide a non-destructive through-thickness residual strain analysis in thermally sprayed components with a level of detail not normally achievable by other techniques. Neutron sources have been used to measure strains in thermal spray coatings, and here, we present examples where such coatings have been characterised at various neutron sources worldwide, to study residual strains and microstructures. Graphic Abstract

Understanding the phase formation mechanisms in self-propagating high-temperature synthesis from the thermodynamical aspect of view is important. In this study, the phase formation of the ternary system of nickel-titanium-silicon was studied by using the HSC software V6.0, and phase formation is predicted by calculating the adiabatic temperature of exothermic reaction between reagents. Then, by using X-ray diffractometer analysis, the results of the simulation were evaluated by experimental achievements. Results showed a good correlation between thermodynamical calculation and prediction with experimental. It could be concluded that the equilibrium mechanism is the dominant mechanism in phase formation in the SHS synthesis method. NiTiSi solid solution phase is obtained from the reaction between Ti5Si3 and Ni2Si and Ni.

In this work, a high-performance up-conversion submicron materials for Yb3+–Tm3+–Er3+ triple-doped lutetium vanadate (LuVO4) obtained via simple solid-state method. X-ray diffractometer results showed that the prepared LuVO4: Yb3+/Tm3+/Er3+ samples kept the crystal phase structure of the host LuVO4. Under 980 nm excitation, LuVO4:Yb3+/Tm3+ phosphors exhibited strong blue light emission. After doping of Er3+ ion the color of LuVO4: Yb3+/Tm3+/Er3+ phosphors were gradually changed from the blue to the green region in the CIE map. Next, the luminous color was evaluated by the correlated color temperature. The temperature-sensing characteristics of material were studied by fluorescence intensity ratio (FIR) technology which based on thermal coupling levels (TCLs) and non-TCLs, respectively. It was found that the maximum value of Sa2 is 0.03555 K−1@370 K based on the non-TCLs of 1G4 (Tm3+) and 2H11/2 (Er3+), which is higher than the sensitivity of Sa1 0.01004 K−1@370 K obtained through the TCLs of 4S3/2 (Er3+) and 2H11/2 (Er3+). For Yb3+/Tm3+/Er3+ co-doped LuVO4 up-conversion phosphors, the results demonstrate its great potential for fluorescence display and temperature probing.

(Ho,Nd)FeB magnets with different Ho contents were prepared by Ho substitution for part of Nd during the casting process. Effects of Ho contents on the corrosion resistance and mechanical properties of (Ho,Nd)FeB magnets were analyzed by a highly accelerated aging tester, an electrochemical workstation, a microhardness tester, a bending tester, a scanning electron microscope and an X-ray diffractometer. Results show that the addition of Ho can change the main phase structure, optimize the distribution of rare-earth rich (RE-rich) phases in grain boundary, and improve the corrosion resistance and mechanical properties of NdFeB magnets. When the content of Ho increases from 0 to 21.0 wt%, the weight loss of magnets decreases from 2.672 to 0.933 mg/cm2, and the microhardness and bending strength increase from 528.74 HV and 374.92 MPa to 633.84 HV and 459.80 MPa, respectively.

In order to enhance the plasma nitriding efficiency and improve the hardness and wear resistance of 316L austenitic stainless steel, severe plastic deformation was adopted prior to plasma nitriding. The microstructure, phase constituents, hardness and wear resistance samples after plasma nitriding were determined by metallographic microscope, X-ray diffractometer, microhardness tester and universal friction and wear tester. The results showed that severe plastic deformation had significant enhancement effect on plasma nitriding efficiency. Under the same plasma nitriding parameters of 420 °C and 4 h, the thickness of nitriding layer was increased from 6.36 μm to 14.10 μm, more than twice thicker enhanced by severe plastic deformation. XRD confirmed that the nitriding layer is consisted of S phase. Meanwhile, the surface hardness was improved from 990HV to 1110 HV and with moderated gradient of cross sectional hardness; more valuably, the wear resistance was greatly enhanced by severe plastic deformation.