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High-temperature synthesis of the perovskite composite material i.e., 0.5(SmFeO3)-0.5(Ba0.5Sr0.5TiO3) or SFO-BST was proficiently developed through solid-state reaction technique. X-ray diffractometer was utilized to analyze the polycrystalline single stage, and Rietveld Refinement approved the development of the tetragonal phase (P4mm) in the crystalline material. The dielectric, impedance, conductivity and optical behavior of the synthesized specimen have been scrutinized. At room temperature and above, the sample shows a large dielectric constant and a small tangent loss, making it an appropriate material for microwave absorbers. The complex impedance analysis demonstrates the influences of the grain and the grain boundary. The material's efficacy to be used in a new multiferroic device is supported by its ferroelectric and ferromagnetic properties. Furthermore, the application in semiconductor photovoltaic cells is endorsed through the UV–VIS data analysis. [ABSTRACT FROM AUTHOR]

In the present investigation, we report a comparative study of structural, magnetic and electric transport properties in bulk NiFe 2 O 4 and Ni 0.7 Zn 0.3 Fe 2 O 4 ceramics. The materials were synthesized by solid state reaction method. X-ray diffraction analysis confirmed the cubic spinel structure of the ferrite samples belonging to the Fd 3 ‾ m space group. The structural analysis of the ceramics was comprehensively evaluated from Rietveld refinements of the XRD data and Raman studies. An increased grain size in the Ni 0.7 Zn 0.3 Fe 2 O 4 microstructure was noticed due to Zn substitution. Both structural and microstructural modifications led to a significant change in the magnetic and electric properties of the Ni 0.7 Zn 0.3 Fe 2 O 4 ceramic. A large increase in saturation magnetization with decreased coercivity was noticed in the Ni 0.7 Zn 0.3 Fe 2 O 4 system due to Zn substitution. DC resistivity was observed to decrease in the Zn-substituted nickel ferrite ceramic due to increased grain size and larger electron hopping between Fe3+ and Fe2+ ions, as verified by the XPS analysis. Further, a remarkable dielectric relaxation has been observed in the Ni-Zn ferrite owing to greater charge hopping and interfacial polarization. Complex impedance spectra of Ni 0.7 Zn 0.3 Fe 2 O 4 revealed evidence of surface polarization contribution with grain and grain boundary effect on the electric transport properties. [ABSTRACT FROM AUTHOR]

As challenges in precious and base metal exploration intensify due to the diminishing availability of high-grade ore deposits, rising demand, energy costs, and stricter regulations towards net-zero carbon activities, advanced techniques to enhance exploration efficiency are becoming increasingly critical. This study demonstrates the effectiveness of quantitative X-ray diffraction (QXRD) with Rietveld refinement, coupled with multivariate statistical analysis (including agglomerative hierarchical clustering, principal component analysis, and fuzzy analysis), in characterizing the complex mineralogy of strata-bound volcanic-associated limestone-skarn Zn-Pb-Ag-(Cu-Au)-type sulphide deposits (SVALS). Focusing on 113 coarse rejects from the Gumsberg project located in the Bergslagen mining district in central Sweden, the research identified five distinct mineralogical clusters corresponding to polymetallic base metal sulphide mineralization, its proximal alteration zones, and variably metamorphosed host rocks. The results reveal significant sulphide mineralization, ranging from disseminated to massive occurrences of sphalerite, pyrrhotite, pyrite, and galena, with trace amounts of secondary minerals like anglesite in certain samples indicating weathering processes. The study also identifies rare minerals such as armenite, often overlooked in traditional geological logging. These findings underscore the potential of QXRD to enhance resource estimation, optimize exploration strategies, and contribute to more efficient and sustainable mineral exploration programs. The accuracy of QXRD was cross-validated with geological logs and geochemical data, confirming its reliability as a mineralogical discrimination tool. [ABSTRACT FROM AUTHOR]

This article reports the synthesis of MnO2/Mn2O3 nanocomposite, which can be used in forming the anode for supercapacitor applications. The MnO2/Mn2O3 nanocomposites are synthesized via the sol–gel route and are characterized in context of structural parameters by X‐ray diffraction technique, field emission‐scanning electron microscopy (FE‐SEM), and supercapacitive behavior by cyclic voltammetry (CV) , galvanostatic charging and discharging (GCD), and electrochemical impedance spectroscopy. The spinel structure of MnO2/Mn2O3 nanocomposite with space groups Ia3 and I4/m for Mn2O3 and MnO2 nanocomposite is confirmed by the Rietveld refinement, respectively. The FE‐SEM micrographs reveal the nanosphere‐type shape of the MnO2/Mn2O3 nanocomposite. According to outcomes of electrochemical measurements, the nanocomposite exhibits good capacitive behavior in aqueous electrolyte KOH, demonstrating the highest specific capacitance (763 F g−1) at 1 Ag−1 current density from GCD. In CV, it has shown excellent performance with specific capacitance (642.93 F g−1) at 10 mV s−1. Additionally, the prepared nanocomposite‐enhanced electrolyte ion interaction may cause rapid charging and discharging, even at low current densities. [ABSTRACT FROM AUTHOR]

Cancer treatment remains a pressing global challenge, with magnetic hyperthermia emerging as a promising alternative approach. The article explores the potential of pure and doped magnetite nanoparticles for hyperthermia-based cancer treatment, aiming to enhance therapeutic efficacy while minimizing side effects. Key findings include the synthesis and characterization of NPs—Fe3O4, SnFe2O4, and CoFe2O4—using co-precipitation methods, with emphasis on their size, morphology, magnetic, structural and thermal properties confirmed through techniques like SEM, EDX, VSM, XRD and TGA. The nanoparticles' hyperthermic effects were assessed through infrared imaging, showing CoFe2O4 NPs induced the highest heating efficiency as compared to Fe3O4 and SnFe2O4 NPs. Importantly, all nanoparticles showed negligible hemolysis at a concentration of 0.2 mg/ml, indicating their compatibility with human blood. This study contributes valuable insights into optimizing MNP-based hyperthermia treatments, aiming for safer and more effective cancer therapies in the future. SnFe2O4 NPs haven't been extensively explored in the context of hyperthermia applications, making it a unique contribution to the field. The research employs an innovative and cost-effective method for evaluating the hyperthermic effect of nanoparticles using an infrared camera. This approach overcomes the potential limitations associated with probe-based temperature measurement, offering a more accurate assessment of nanoparticle-induced hyperthermia. The research thoroughly compares its findings with existing literature, highlighting the novelty of the achieved results in terms of maximum hyperthermia with minimal frequency and magnetic field strength without inducing toxicity in human blood. [ABSTRACT FROM AUTHOR]

By examining the diffraction data, the microstructure of the ball-milled synthesized powder sample ( Ba 0. 9 9 9 8 Pr 0. 0 0 2 TiO3) was characterized. Through the application of Rietveld's powder structure refinement approach to analyze X-ray powder diffraction data of ball-milled powder mixes, structural and microstructural alterations in terms of lattice defects have been assessed in the formation of single-phase praseodymium-modified BaTiO3. Bond lengths, bond angles, and generated locations of the Ba 0. 9 9 8 Pr0 . 0 0 2 TiO3 ceramic have been discussed about its generated structure. X-ray diffraction with respect to the first sharp diffraction peak (FSDP) is used to study the nanostructure of void species. General equations were utilized to determine various FSDP characteristics such as interlayer separation, correlation length, nanovoid diameter and scattering vector magnitude. Although the literature reports on many properties of Pr-modified barium titanate ceramic, this sample's quantitative analysis and nanovoid determination are presented for the first time. [ABSTRACT FROM AUTHOR]

In this research, reduced graphene oxide (rGO) material from coconut shell charcoal was synthesized using the modified Hummer method. The reduction process of Graphene Oxide (GO) to rGO uses the reducing agent L-Ascorbic Acid (LAA) and is assisted by microwave radiation. The samples obtained were then characterized using XRD to analyze the crystal structure parameters of the rGO samples obtained. Based on the XRD results, the data obtained was then analyzed using the Scherrer and modified Scherrer equations to determine the crystal size in the sample. In addition, the Williamson-Hall equation is also used to analyze crystal size and lattice strain. This article also analyzes XRD data using the Rietveld method using Rietica software. The output from the Rietica software obtained lattice parameter values a ≠ b ≠ c and angle α = β = γ = 90° which indicates an orthorhombic crystal lattice structure. In the refinement process, Rietica's software affects the suitability parameters in the form of R and GOF indicator values. The sample obtained was also measured for the electrical conductivity value of the rGO sample using an LCR meter.

Multi-component systems involving the high-entropy and the medium-entropy perovskites stimulate the incorporation of additional components to facilitate the simultaneous customization of a range of properties, thereby unlocking their potential for novel functionalities. A new class of multicomponent perovskite oxides with the participation of rare earth elements has been synthesized. The three compositions which were produced by mechanical alloying involved Sm(Ti 0.18 Cr 0.23 Ni 0.29 Cu 0.30)O 3 , Eu(Ti 0.18 Cr 0.23 Ni 0.29 Cu 0.30)O 3 and Gd(Ti 0.18 Cr 0.23 Ni 0.27 Cu 0.32)O 3. The Goldschmidt's tolerance factor predicts the stability of the multicomponent perovskite crystal structures. Furthermore, to provide a theoretical viewpoint on the above perovskites, a density-functional study of all the structures along with the single-metallic perovskites has been performed. The formation energy of the structures (three multi-component and 12 single-metallic perovskites) confirms the stability and also their formation. Furthermore, the energy gap detected in the spin-down channels of the multicomponent materials suggests a promising potential for these systems as a spin filter in spintronic applications. The magnetic characteristic could be helpful for tuning the physical characteristics of the perovskites and could modify drastically their transport properties. [ABSTRACT FROM AUTHOR]

The study on the evolution of natural ferroan brucite (MgFe(OH) 2) was beneficial to discovering the function of brucite in the geologic cycle and directing the reasonable utilization of brucite resources. In this study, natural MgFe(OH)2 was characterized in detail and Rietveld refinement was employed to determine the precise content and existing environment of Fe 2 + . The reaction products of MgFe(OH)2 under various atmospheric conditions, including CO2, O2 and a mixed atmosphere of CO2 and O2 were innovatively investigated to gain insights into the evolution process and the crucial role played by Fe 2 + . Accordingly, the evolution mechanism of MgFe(OH)2 under different atmospheres was afforded based on the characterization and molecular simulations like electron transfer and binding energy. Fe 2 + in MgFe(OH)2 layers could be oxidized by O2 easily and give positive layers, CO 3 2 − produced by CO2 dissolving in water simultaneously was attracted to finally produce CO 3 2 − intercalated MgFe- layered double hydroxides (MgFe-CO 3 2 − -LDHs) which could be used as adsorbents, catalysts and so on. This process was supported by thermodynamics and also the dominant evolution route due to the dynamic reason. The existence of Fe 2 + in MgFe(OH)2 resulted in the diversity of the evolution products. This work highlighted the composition and structure of evolution products of natural MgFe(OH)2 under different environment as well as its possible application field. The evolution of MgFe(OH)2 under various atmospheric conditions was studied. The existence of Fe 2 + changed the evolution route of MgFe(OH)2 and made the reaction products diverse. Fe 2 + in MgFe(OH)2 layers could be oxidized by O2, and CO2 could be then adsorbed on the surface to finally produce MgFe-CO 3 2 − -LDHs thermodynamically. Due to dynamic reasons, the layers of MgFe(OH)2 would become positive because of the oxidation of Fe 2 + , CO 3 2 − in water was simultaneously attracted to produce MgFe-CO 3 2 − -LDHs. [ABSTRACT FROM AUTHOR]

The purpose of this investigation is to examine the evolution of phase formation, structural, microstructural, and magnetic properties of the Fe50Cr40P10 (wt.%) powder mixture as a function of milling time. The Rietveld refinements of X-ray diffraction patterns indicated the formation of two bcc chromium solid solutions, Fe33Cr2 and Fe2Cr5, embedded within α-Fe (P) solid solution. The magnetic measurements reveal a ferromagnetic behavior regardless of milling time, but highlight a new behavior of phosphorus as an alphagen element to promote the alpha iron chromium solid solution formation with lower hysteresis loss energy and maximum values of the magnetic properties (coercivity, Hc, nucleation field, Hn, initial µi and maximum µmax magnetizations permeabilities as well as the hysteresis loss energy EHL). The evolution of magnetic fields has been correlated with the evolution of , rms <σ2>1/2, and dislocation density ρ. [ABSTRACT FROM AUTHOR]

This study explores the synthesis and characterization of Fe-doped CaTiO3 compounds via the Pechini method, focusing on their structural, magnetic, and electrical properties. Notably, a previously unreported magnetic property is observed in the Fe-doped CaTiO3 compound. Despite significant structural distortions, ferroelectric polarization is identified using the Geometrical Polarization Approach (GPA), indicating its emergent nature. These distortions are attributed to robust chemical bonds between ionic O1−2 and Ti+4 sites, as evidenced by electronic density maps. This research sheds light on the potential of these materials for various technological applications. [ABSTRACT FROM AUTHOR]

Nanocrystalline system of pristine Ho2O3 (HO) and Co-doped Ho2O3 (Ho1.9Co0.1O3-δ, HCO) were synthesized by chemical co-precipitation method. These samples were investigated by analyzing structural, morphological and magnetic data. To enhance the oxygen vacancy, both HO and HCO samples are annealed in argon atmosphere at 700 ∘ C for 6 h. Rietveld analysis of X-ray diffraction (XRD) pattern of both samples confirmed the desired crystallographic phase and successful substitution of Co-ion in Ho2O3. Microstructural analyses of prepared samples are also performed by Rietveld refinement method. Energy dispersive X-ray (EDAX) and X-ray photoelectron spectroscopy (XPS) analysis confirm that impurity phases like Co3O4 and CoO are absent in HCO. Also, XPS analysis indicates that mismatch of ionic valence state of dopant ion Co2+ and host cation Ho3+ introduces oxygen vacancy in HCO. Magnetization (M) as a function of applied magnetic field (H) of both bare and doped samples are recorded at different temperatures as a function of magnetic field in the range of ~ − 5 T to 5 T. Nonlinearity in M-H loops recorded at ~ 50 K indicates the presence of magnetic ordering below ~ 50 K for both samples, but the signature of ordering in doped sample more prominent than that of the pristine. Good fitting of magnetization vs. temperature curve below ~ 50 K by the combined equation of 3D spin wave model and Curie–Weiss law and lack of saturation of M-H loop below ~ 50 K indicates coexistence of paramagnetic (PM) and ferromagnetic (FM) phases in both samples. The observed magnetic phase transition is explained by vacancy mediated bound magnetic polaron (BMP) model. Also, antiferromagnetic transition in the doped sample is observed at 3 K. [ABSTRACT FROM AUTHOR]

Powder XRD approaches are applied for proving of moganite in an agate from Lozevo village (Shumen region). Moganite associates with silica minerals - quartz (quartzine and chalcedony), opal-CT and opal-A, all being characteristic for agates. Quartz and moganite display similar structures and thus the powder XRD pattern of moganite significantly overlaps with that of quartz and distinguishing of moganite is difficult. However, some of its diffraction peaks are well observed - with inter-planner spacings (d) 4.43 Å, 3.388 Å, 3.116 Å. The presence of moganite is proved in the agate of study in all its zones. The applied XRD quantification by use of full-pattern Rietveld-based refinement showed moganite quantities from 21 to 31 wt% in the quartzine layers of the agate, 18.57 wt% in the chalcedony zone, and only 1.72 wt% in the quartz shell. The results of these XRD approaches may serve in reconstruction of mineral forming in silica environment. [ABSTRACT FROM AUTHOR]

The main objective of this research is the explanation of the replacement of feldspar limestone imported from Spain with recycled automotive glass, in order to reduce waste and promote environmental sustainability. Details and efforts of making porcelain ceramics from local raw materials such as quartz, kaolin and glass are also given. Replacing the feldspar with reclaimed automotive glass shows the effect of the Na2O and CaO solvents contained in the glass on the sintering and crystallization of the studied porcelain. The results showed that the added glass contributes to the reduction of the density and the acceleration of the sintering process, by occupying the sites of the open spaces, observed in the samples not containing feldspars. By reaching a nonporous ratio at a temperature of 1000∘C, the melting of the material is accelerated due to the dissolved oxides it contains, in addition to the linear shrinkage rate in samples that contain a lot of glass reaching the normal level of porcelain (about 12%) at low temperature compared to ordinary porcelain. [ABSTRACT FROM AUTHOR]

In our study, we aimed to synthesize the Cu2Sb phase with a tetragonal structure. We achieved this by subjecting compacts (2Cu + Sb) to electrothermal explosion (ETE) with a high current density of 500 Å. To analyze the constituent phases of the alloy composite, we employed X-ray diffraction analysis with the MAUD program, which utilizes the Rietveld method, as well as scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) techniques. Furthermore, we investigated the mechanical properties through Vickers indentation and compression techniques. [ABSTRACT FROM AUTHOR]

Quaternary compositions of polycrystalline Bi1.74Dy0.14W0.12−xScxO3 (x = 0.02, 0.03, 0.04, 0.05, 0.06) solid solutions are synthesized by the solid‐state reaction method. The 4a site symmetry of the Fm3¯m$F m \overset{\cdot}{3} m$ space group occupied by Sc3+ ion retains the cubic fluorite‐type over a wide temperature range (450–700 °C) for low Sc3+ content without losing the δ‐phase. Dielectric and ionic conductivity by complex impedance in the frequency range from 0.1 to 100 kHz suggests a temperature‐ and Sc3+‐dependent relaxation process. The ionic conductivity increases with the Sc3+ content over the whole tested temperature range. An oxygen ion conductivity of 0.102 Scm−1 at 700 °C and an activation energy of 0.32 eV are achieved for x = 0.06. Optical properties and Rietveld refinement indicate a bandgap reduction due to a bond length reduction (Bi—O). These materials have potential in photocatalysis and water‐splitting technology due to their UV and visible region absorption capabilities. [ABSTRACT FROM AUTHOR]

In this investigation, highly crystalline and mesoporous Zinc oxide (ZnO) nanoparticles with the large surface area were synthesized without calcination. Furthermore, the effects of different pH values on structural, physicochemical and textural properties of ZnO nanoparticles were comprehensively investigated. Rietveld refinement implied that the pH variation had significant effects on the crystal structure of ZnO nanoparticles. The phase, molecular and elemental structures confirmed the formation of ZnO as a major phase in all nanopowders. The morphology of ZnO nanoparticles was irregular with an average size of 45 ± 9 nm. Both phase and atomic structures confirmed the polycrystalline arrangement of ZnO nanoparticles. Moreover, isotherms confirmed the mesoporous structure of all ZnO nanoparticles with superior specific surface area and porosity volume. Thus, owing to the concoction of high crystallinity, superior surface area and porosity volume, resultant ZnO nanoparticles can be effectively employed for diverse multifunctional therapeutic applications. [ABSTRACT FROM AUTHOR]

The mechanical alloying process has been used to synthesise the nanocrystalline Fe60Al35Mg5 (wt%) powders in a high-energy planetary ball-mill Retsch PM 400. The evolution structural, microstructural and magnetic properties of ball-milled powders at different milling times (t variation from 0 to 32 h) were investigated by X-ray diffraction using the MAUD program which is based on the Rietveld method and the vibrating sample magnetometer. The XRD results reveal the formation of a bcc-Fe (Al, Mg) solid solution after 8 h of milling possessing a lattice parameter of 0.2895 nm after 32 h of milling. It is also observed a refinement of the grain size, which reaches 18.75 nm, and an increase in the microstrain after 32 h of milling. Magnetic measurements of the milled Fe60Al35Mg5 (wt%) powder mixture exhibit a soft ferromagnetic character where the magnetic parameters are found to be very sensitive to the milling time mainly due to the particle size refinement as well as the formation of the solid solutions. [ABSTRACT FROM AUTHOR]

Ni0.65Zn0.35AlxFe2−xO4 that has been synthesized using a solution-gelation method and calcined at 600 °C for 4 h was characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). A single-phase cubic spinel structure belonging to the Fd-3 m space group was confirmed by Rietveld refinement. The cation distribution that was anticipated using the XRD data deviated from the preferential occupancy, and the results of the magnetization analysis supported this. The two absorption bands in the FTIR spectra corresponding to the tetrahedral and octahedral sites further support the establishment of the ferrite skeleton. Al3+ doping was found to have a considerable impact on the Debye temperature, bulk modulus, and stiffness modulus measured using FTIR data. Interatomic bonding became stronger, increasing elastic moduli. The morphology was examined using SEM, whose results showed a cluster of grains. Additionally, spherical nanoparticles with an average size of 28 nm were visible in the TEM image, which is in good agreement with the crystallite size given by the Williamson-Hall method. The Mössbauer analysis and M–H data showed a soft magnetic behavior with coercivity fluctuation. According to Arrhenius plots, all samples displayed a semiconducting characteristic. With Al3+ doping, dielectric studies revealed a declining trend. [ABSTRACT FROM AUTHOR]

Studies suggest that feitknechtite (β-MnOOH) is a prevalent, and perhaps necessary, intermediate phase during the synthesis of birnessite-like phases, the abiotic oxidation of Mn2+, and the transformation of biogenic hexagonal phyllomanganates to more complex Mn oxides in laboratory and natural systems. Researchers have generally described feitknechtite as consisting of pyrochroite-like (or cadmium iodide-like) Mn-O octahedral layers, but a detailed crystal structure has not been reported. We used TEM/SAED and powder XRD and Rietveld refinements to derive the unit cell and, for the first time, report a complete structure description for feitknechtite (β-MnOOH). Rietveld refinements were also completed for three natural feitknechtite/hausmannite samples, and time-resolved synchrotron XRD experiments were used to follow the thermal transformation of feitknechtite to hausmannite. Additionally, we identified and report the structure for a second, and perhaps novel, MnOOH polymorph (proposed designation ε-MnOOH), mixed with the synthetic feitknechtite, that is similar to β-MnOOH but with a different layer stacking. [ABSTRACT FROM AUTHOR]

In magnetron sputtering, with the simultaneous deposition of SmCo and copper, it is possible for tailoring the coercive field of SmCoCu thin films. Microstructural analysis pointed out that nanocrystalline 2:17 rhombohedral phase with diameter 10–100 nm was obtained, and coercivities in the range between 3 and 8.5 kOe. These characteristics are suitable for magnetic recording. The coercivity mechanisms are discussed. The initial magnetization curve, measured in thermally demagnetized samples, is used to discuss the coercivity mechanisms. A spring effect in the samples is observed. The spring effect is due to reversible rotation of magnetization and indicates that the coercivity mechanism is nucleation or coherent rotation of single domain size nanoscale grains. Structural data refined with X-ray diffraction Rietveld analysis for Sm2(Co,Cu)17 rhombohedral phase, Sm(Co,Cu)5 phase and cubic oxide Sm2O3 phase are provided. [ABSTRACT FROM AUTHOR]

Nickel (Ni) doped magnetically separable Cu 1-x Ni x Mn 1.0 Fe 1.0 O 4 ferrite was synthesized using the sol-gel auto-combustion method. The system exhibits a cubic spinel structure with a single phase in all the samples, which was confirmed using Rietveld refinement. Mixed morphology with agglomerated particles with nearly spherical/multi-faceted shapes was observed in FESEM studies. The elemental composition was confirmed from EDAX analysis. TEM images are in well accordance with FESEM images and reveals the crystalline nature of the synthesized samples. Magnetic properties of all the ferrites were studied using VSM. With the increase in the concentration Ni2+ the Cu 1-x Ni x Mn 1.0 Fe 1.0 O 4 ferrite transform from ferrimagnetic character to a superparamagnetic character. The as-synthesized materials were further tested for their electrochemical and supercapacitor applications. The electrochemical measurements revealed that Cu 1-x Ni x Mn 1.0 Fe 1.0 O 4 with (x = 0.75) exhibits superior electrochemical performance over the other samples. The high specific capacitance of 975 F g−1, the high energy density of 20.8 Whkg−1 at a scan rate of 5 mVs-1, and 94.4% capacity retention over 5000 cycles were observed for Cu 1-x Ni x Mn 1.0 Fe 1.0 O 4 with a concentration of x = 0.75. [Display omitted] [ABSTRACT FROM AUTHOR]

The manganates Sm1.5–xSr1 + xBa0.5Mn2O7 for x = 0, 0.1, and 0.3 were successfully synthesized by the co-precipitation route. The compounds' crystalline structures were analyzed through powder X-ray diffraction using the refinement Rietveld method. The refined structure parameters are entirely in agreement with those expected in the case of An + 1BnO3n + 1 for n = 2 corresponding to the iso-structural Sr3Ti2O7 type. Magnetic measurements of Sm1.5–xSr1 + xBa0.5Mn2O7 (x = 0, 0.1, and 0.3) revealed the existence of a predominant antiferromagnetic ordering. Furthermore, isothermal magnetization shows that magnetization saturation is not fully attained at high fields, which can be explained by a strong super-exchange interaction of the antiferromagnetic state. The electrical resistivity at zero field shows that these compounds are electrically insulating materials, which can be explained by the predominance of the antiferromagnetic ordering. [ABSTRACT FROM AUTHOR]

Polycrystalline‐multiferroic Bi0.85Pr0.15‐xEuxFe0.97Mn0.03O3 (0, 0.01, 0.02, 0.03, 0.4, 0.05) thin films were grown on fluorine‐doped tin oxide (FTO)/glass substrate with radio frequency (RF) magnetron sputtering. Rietveld quantitative analysis reveals that whereas the starting materials (nanoparticles [NPs] and ceramics) are composed of tetragonal P4mm symmetry, the thin films can lose 80% of this symmetry to become rhombohedral R3c symmetry. The structure evolution from tetragonal to rhombohedral symmetry indicates that the Eu3+ ion acts positively to reduce the tensile residual stress component from 24 to 1.8 MPa in the thin films. The band gap shifts to 2.17 eV by Eu substitution at the A‐site of the perovskite. Scanning electron microscopy (SEM) results show high‐elongated nanocrystals that share parallel facets without porosity. In that morphology, the Eu has a strong influence on reducing the magnetic coercivity from 10.7 to 6.5 kOe, which has been interpreted in terms of local shape anisotropy. Although the magnetic response increases monotonously, the ferroelectric polarization decreases with doping. These changes are explained through local defects created by the evolution of the VO·· concentration that changes significantly by Eu doping. [ABSTRACT FROM AUTHOR]

A Bi2O3 nanomaterial was fabricated by a facile and low temperature solid state method using a basic bismuth nitrate raw compound at 400 ˚C and 14 h. Rietveld analysis data indicated that α-Bi2O3 was crystallized well in monoclinic crystal system with the space group of P121/c1. The morphology of the synthesized material was studied by field emission scanning electron microscope (FESEM). The direct band gap energy (Eg) value was calculated by ultraviolet – visible (UV-Vis) spectroscopy. The peaks at 400 – 550 cm-1 are assigned to oxygen – metal – oxygen (O-M-O) vibrations. The data showed that the Eg of the synthesized material was about 2.2 eV. In addition, the vibrating-sample magnetometer (VSM) analysis data confirmed that the synthesized sample had ferromagnetic behavior. Further, gas sensing property of the synthesized Bi2O3 nanomaterial for carbon monoxide gas was studied, and the data confirmed the good sensitivity of the prepared sensor at low CO concentrations.

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Mx‐MoO3‐α‐NaFe2(MoO4)3‐α‐FeMoO4 (M = Al, Co, Ni, and Er) nanomaterials were fabricated by the hydrothermal method in the present study. XRPD, FESEM, TEM, BET‐BJH, UV‐Vis, and VSM analyses were used to characterize and study the physical attributes of the as‐synthesized samples. Rietveld analysis data illustrated that the products were a mixture of α‐NaFe2(MoO4)3, α‐FeMoO4, MoO3, and Fe2O3 crystal phases. UV‐Vis spectra indicated that the obtained samples had a small direct band gap energy amount at about 1.3–1.5 eV. VSM analysis confirmed that the as‐fabricated samples had magnetic properties. However, most ferromagnetic behaviors were observed by doping Ni into the host crystal system. Catalytic synthesis of some 5‐aryl‐1H‐tetrazole analogs was performed under heat, microwave, and ultrasonic conditions. Reaction time, temperature, and solvent type parameters were studied to find the optimum conditions. High efficiency was obtained when ethyl alcohol was used as the reaction mixture solvent. [ABSTRACT FROM AUTHOR]

CoFe2O4 nanocrystals were synthesized through chemical co-precipitation using citric acid as the capping agent. Subsequently, a green alternative was accomplished in the synthesis process by replacing the commercially purchased citric acid with naturally available lemon juice. The prepared samples were thoroughly characterized using various techniques, and the results were analyzed and the parametric variations in the two samples were compared. Using Rietveld profile refinement of the XRD patterns, the crystallographic parameters associated with both samples were explored and the cation distributions in the tetrahedral and octahedral sites were estimated. Williamson–Hall analysis of x-ray diffraction data provided the effective crystallite size and the microstrain associated with the nanocrystalline samples. The optical direct band gap and the room-temperature magnetic parameters were estimated from UV–visible spectra analysis and vibrating sample magnetometry, respectively. The coercivity, remanent magnetization, and saturation magnetization of both samples were obtained from magnetic hysteresis, and the estimated values for magnetic anisotropy energy revealed that the samples exhibited room-temperature ferrimagnetic behavior. [ABSTRACT FROM AUTHOR]

The allotropic transformation, characteristic of cobalt-based alloys, occurs at around 970 ºC in Co-28Cr-6Mo alloys. When subjected to fast cooling, such alloys can maintain the high temperature cubic centered phase at room temperature, resulting in a CFC metastable matrix. This metastable condition leads to a nucleation of the hexagonal phase (the stable one), which is induced by deformation or isothermally. In general, Co-based alloys are submitted to solution heat treatment plus aging to control both the precipitation of carbides and the nucleation of the hexagonal phase. When the study of this type of alloy is conducted in the metastable condition, it is extremely important do not induce the hexagonal phase during sample preparation. Traditionally, the metallographic route preparation is carried out using electropolishing to avoid the deformation-induced phase transformation. The need for specialized equipment and hazardous electrolytes to perform electropolishing limits its use. Therefore, the aim of the present work is to propose the use of an adaptation to traditional metallographic techniques in order to prepare Co-28Cr-6Mo alloy samples. To this end, the samples prepared by three different routes were analyzed by X-Ray diffraction, including Rietveld refinement, as well as EBSD in order to identify and quantify the phases present in the structure. A control cold rolled sample was also analyzed. The results showed a significant reduction in the HCP phase fraction, strain-induced during grinding, after the application of the alternative preparation method proposed. Further studies might be useful to validate the present methodology.

This paper aims to analyze the structure of the Ti-25Ta-xZr system alloys (x = 0, 10, 20, 30, and 40% wt.) after melting and hot-rolling by Rietveld's technique. The results confirm that zirconium acts as a β phase stabilizer (in which the Ti-25Ta-40Zr alloy is fully β in the as-cast condition), increases the lattice parameters of the phases, decreases the c/a ratio of the α phase, consequently, decreases the elastic modulus values (86 to 72GPa) and decreases the atomic packing factor (APF) of the alloys (60% reduction compared to alloys with and without zirconium in the as-cast condition and 50% reduction in the hot-rolled condition). Concerning hot-rolling, this mechanical process induces the α phase formation and increases the atomic packing factor of the alloys (APF). By the William-Hall technique, it was possible to calculate the average crystalline size and the micro-strain of the structures.

X-ray diffraction (XRD) analysis, as one of the most powerful methods, has been widely used to identify and quantify minerals in earth science. How to improve the precision of mineral quantitative analysis is still a hot topic. To date, several quantitative methods have been proposed for different purposes and accompanied by diverse software. In this study, three quantitative mineral analysis methods, including the reference intensity ratio (RIR), Rietveld, and full pattern summation (FPS) methods, are compared and evaluated to systematically investigate their accuracy and applicability. The results show that the analytical accuracy of these methods is basically consistent for mixtures free from clay minerals. However, there are significant differences in accuracy for clay-mineral-containing samples. In comparison, it seems that the FPS method has wide applicability, which is more appropriate for sediments. The Rietveld method has been shown to be capable of quantifying complicated non-clay samples with a high analytical accuracy; nevertheless, most conventional Rietveld software fails to accurately quantify phases with a disordered or unknown structure. The RIR method represents a handy approach but with lower analytical accuracy. Overall, the present results are expected to provide a potentially important reference for the quantitative analysis of minerals in sediments. [ABSTRACT FROM AUTHOR]

SrTiO3 is a well-known photocatalyst with various applications, such as antibacterial agents, self-cleaning surfaces, and water and air conditioning. With the increased environmental pollution, SrTiO3 is one of the most studied perovskite photocatalysts, exhibiting pronounced photocatalytic activity for removing chemical pollutants and water splitting. In the present work, pure Strontium titanate (ST) nanoparticles were successfully prepared using high-energy ball milling and Pechini techniques and characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), Fourier Transform Infrared spectroscopy (FTIR), scanning and transmission electron microscopy, respectively. Structural parameters were evaluated by Rietveld refinement analysis from XRD data, which confirmed the cubic system of SrTiO3 with Pm-3 m space group. Scanning electron microscope results showed that ST1 samples consisted of agglomerated and irregular-shaped structures between 20 and 40 nm, and in ST2, the particles were round-shaped and had an average size of 150 nm. The obtained nanoparticles were used for photocatalytic methylene blue (MB) degradation, and synthesis methods' influence on catalytic activity was investigated. The photocatalytic studies examining the decoloration of MB dye reveal the function of smaller particles in increasing the rate of reactions. The degradation rate constant of MB on the ST1 (Pechini-synthesized sample) and ST2 (high energy ball milled sample) is 0.0145 and 0.0112 min−1, respectively. The better photocatalytic activity of the ST1 demonstrated 93% degradation of dye under the solar light simulator. The photocatalytic reaction data provided well a first-order kinetic model. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanopowder samples were prepared by using co-precipitation method, with varying parametric conditions. Rietveld refinement technique is used to study the structural properties of synthesized samples. XRD and UV spectroscopy techniques have been used to characterize the samples which resemble ZnO nanostructures. Observed lattice parameters are a = b = 3. 2 4 8 2 Å and c = 5. 2 0 1 1 Å for sample A, a = b = 3. 2 5 0 0 Å and c = 5. 2 0 6 2 Å for sample B, a = b = 3. 2 4 9 7 Å and c = 5. 2 0 1 7 Å for sample C, a = b = 3. 2 5 5 0 Å and c = 5. 2 1 2 2 Å for sample D. The varying unit cell volume and axial ratio for all samples are calculated as 47.52–47.82 Å and 1.6006–1.6019. VESTA software is used to calculate the bond angles and lengths of Rietveld refinement data. UV-Vis spectroscopy analyzed the absorption, transmission, refractive index and band gap of samples for their possible use in different industrial applications. [ABSTRACT FROM AUTHOR]

The ability to integrate multiple distinct properties into a single structure is the driving force behind the development of NiTi to Ti6Al4V dissimilar joints. However, differences in thermophysical properties and the subsequent development of brittle Ti2Ni and Ni3Ti intermetallic compounds (IMCs) make fusion welding of these alloys rather challenging. The solidification of brittle IMC causes cracking upon solidification and a significant reduction on the joint mechanical properties. In this study, two strategies were used concurrently to reduce the formation of brittle IMC: zirconium (Zr) interlayer was introduced alongside with the laser beam being offset to the Ti6Al4V side. The influence on microstructural evolution was investigated using various characterization techniques. Scanning electron microscopy aided by energy dispersive spectroscopy and micro-X-ray diffraction supported by Rietveld refinement revealed that the volume fraction of the Ti2Ni brittle phase was drastically reduced from 90 to 9%, leading to improvements on the joint mechanical performance. A joint with a lower hardness of 392 HV was obtained, compared to 515 HV for the conventional NiTi/Ti6Al4V joint. The strength and ductility of the Zr-interlayered joint were improved to 320 MPa and 1.7%, respectively, compared to 148 MPa and 0.8% for the Zr-free joint. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles (IONPs) were synthesized via a block copolymer-assisted hydrothermal method and the phase purity and the crystal structure were investigated by X-ray diffraction. The Rietveld analysis of X-ray diffractometer spectra shows the hexagonal phase symmetry of α-Fe2O3. Further, the vibrational study suggests Raman active modes: 2A1g + 5Eg associated with α-Fe2O3, which corroborates the Rietveld analysis and orbital analysis of 2PFe. The superparamagnetic behavior is confirmed by magnetic measurements performed by the physical properties measurement system. The systematic study of the Congo red (CR) interaction with IONPs using a UV-visible spectrophotometer and a liquid chromatography–tandem mass spectrometry system equipped with a triple quadrupole mass analyzer and an electrospray ionization interface shows effective adsorption. In visible light, the Fe2O3 nanoparticles get easily excited and generate electrons and holes. The photogenerated electrons reduce the Fe3+ ions to Fe2+ ions. The Fe2+/H2O2 oxidizes CR by the Fenton mechanism. The strong adsorption ability of prepared nanoparticles towards dyes attributes the potential candidates for wastewater treatment and other catalytic applications. [ABSTRACT FROM AUTHOR]

Carbon doping is studied in MgB2 pellets during one‐step synthesis by solid‐state reaction, employing both undoped and carbon‐doped boron with and without the addition of nano‐SiC. The phase formation during the synthesis as a function of time was followed using powder X‐ray diffraction and Rietveld refinement. The superconducting properties were characterized with a magnetometer to investigate doping‐induced changes. Mg(B1–xCx)2 is obtained with nano‐precipitates and different compositions depending on the synthesis temperature. It is found that the addition of nano‐SiC prevents the phase formation at low temperature (700°C). Nevertheless, the best superconducting properties are obtained for the sample treated at 900°C using simultaneously C and SiC, with a critical current density of 105 A cm−2 at 3 T and 20 K, named the 900‐20‐C‐nanoSiC sample. [ABSTRACT FROM AUTHOR]

Carbon doping is studied in MgB2 pellets during one‐step synthesis by solid‐state reaction, employing both undoped and carbon‐doped boron with and without the addition of nano‐SiC. The phase formation during the synthesis as a function of time was followed using powder X‐ray diffraction and Rietveld refinement. The superconducting properties were characterized with a magnetometer to investigate doping‐induced changes. Mg(B1–xCx)2 is obtained with nano‐precipitates and different compositions depending on the synthesis temperature. It is found that the addition of nano‐SiC prevents the phase formation at low temperature (700°C). Nevertheless, the best superconducting properties are obtained for the sample treated at 900°C using simultaneously C and SiC, with a critical current density of 105 A cm−2 at 3 T and 20 K, named the 900‐20‐C‐nanoSiC sample. [ABSTRACT FROM AUTHOR]

Clay minerals possess chemical, mineralogical, and crystallographic characteristics that make them potential forensic markers, as they can reflect geochemical and weathering processes on a detailed scale. Therefore, this study aims to use the mineralogy of the clay fraction to distinguish samples from the surface soil horizons in four municipalities in Brazil, to assess the possibility of geographical tracking for forensic applications. Studies characterizing clays in environments with a variety of soil types in forensic pedology are necessary but still in their early stages. Furthermore, due to the high incidence of homicides involving the displacement of bodies in the region and the low resolution of these crimes, this research is crucial for geoscientific applications, with the potential for global replication. The samples were separated by centrifugation and analyzed using X-ray diffractometry, X-ray fluorescence, and thermogravimetry. Minerals were determined through quantitative mineralogical analyses using Rietveld and Biscaye methods. Additionally, in conjunction with the crystallographic parameters of kaolinite (Full Width at Half Maximum – FWHM), it was possible to form 8 Clay Mineral Assemblages and Gibbsite (CMAG), whose geographical delimitation considered geological and hydrographic aspects. The determination of CMAGs is based on mineralogy and is defined as follows: CMAG 1: kaolinite+(illite); CMAG 2: kaolinite+(gibbsite); CMAG 3: kaolinite + illite + montmorillonite; CMAG 4: kaolinite + illite+(gibbsite); CMAG 5: ordered kaolinite+(illite)+(gibbsite); CMAG 6: kaolinite + gibbsite+(illite); CMAG 7: disordered kaolinite + illite + gibbsite; CMAG 8: kaolinite+(illite)+(chlorite). The results indicate that the quantification of clay minerals in samples from surface soil horizons, FWHM, and the % of Al in goethite can represent valuable tools for forensic pedology. Moreover, through the characterization of iron and titanium (hydr)oxides, it was possible to distinguish samples with a distance of 335 m between them, further expanding the capability to identify the geographical origin of samples, making them potential forensic markers. • The characterization of clays is a valuable tool for forensic pedology. • The crystallinity of kaolinite is useful for characterizing soil surface horizons. • The Al percentage in goethite proves to be a useful tool for soil characterization. • The joint quantification by Rietveld and Biscaye is useful for clay quantification. [ABSTRACT FROM AUTHOR]

• Zn-doped nanocrystalline Nickel Ferrite (Zn x Ni 1-x Fe 2 O 4) was successfully synthesized using the sol–gel method with Zn substitution values of x = 0.2, 0.4, 0.6, and 0.8. • Rietveld refinement shows an increase in lattice parameter (8.389 Å to 8.421 Å) with increasing Zn content. • The hopping lengths of both A and B sites increase linearly with Zn substitution, implying higher energy is required for charge carriers to transition between cationic sites. • FESEM images confirm homogeneous nanoparticles, and EDAX analysis shows uniform elemental distribution. • Two broad bands in FTIR spectra correspond to the metal–oxygen bond stretching at tetrahedral sites (υ1) and bending at octahedral sites (υ2). • UV–Vis spectroscopy reveals an increase in band gap energy from 2.207 eV to 2.331 eV with higher Zn content. • A green emission near 542 nm is linked to oxygen vacancies. • M−H curves indicate superparamagnetic behavior at room temperature, with no coercivity or remanent magnetization. The nanocrystalline Zn-doped Nickel ferrite nanoparticles, Zn x Ni 1-x Fe 2 O 4 (x = 0.2, 0.4, 0.6 and 0.8) have been developed using the sol–gel method. The average crystallite size was calculated using the Debye- Scherrer formula through X-ray diffractometry and found to be in the range of ∼ 4 nm to 7 nm. Rietveld refinement of the prepared samples suggested the cubic spinel phase of the nanoparticles. For the surface morphology analysis of the nanoparticles, the Field Emission Scanning Electron Microscope (FESEM) technique was utilized, which showed the spherical shape of the particles. Elemental Dispersive X-ray spectroscopy (EDAX) ascertained the experimentally obtained elemental composition with the calculated elemental composition and identified the elements present within the sample. Fourier Transform Infrared Spectroscopy (FTIR) revealed the two prominent absorbing bands, i.e., tetrahedral complex, υ1 and octahedral complex, υ2 in the range of 4000–300 cm−1. Photoluminescence spectroscopy and UV Visible diffuse reflectance spectroscopy determined the optical properties of the samples and it was observed that with the increasing concentration of Zinc, the value of band gap decreased from 2.29 eV to 2.11 eV. The M−H curves of the Zn-doped nickel ferrites exhibit superparamagnetic behavior at room temperature, confirming the presence of a single domain in the sample. [ABSTRACT FROM AUTHOR]

This work reports the magnetic phase transition in the polycrystalline La0.90Pr0.10Mn0.8Co0.2O3 perovskite sample. The solid-state reaction was used for the synthesis of the polycrystalline sample. The detailed study of this polycrystalline sample includes the structural characterization by Rietveld refinement. The surface morphology by FESEM demonstrates a well-prepared sample. The EDAX spectra show the elemental confirmation in the prepared sample. For the detailed magnetic study, M–T and M–H measurements were performed by applying various external magnetic fields at various temperatures. The ZFC and FC curves have been measured under variable temperatures and they show the magnetic phase transition from ferromagnetic to paramagnetic. Also, the splitting between ZFC and FC curves depicts the relaxation mechanism in the sample. The scaling law suggests the orientation, strain effects, and domain structures. The FWHM of the peaks of both (ZFC & FC mode) is increasing with the applied field. This may be due to the magnetic relaxation in the sample. The M–H loops also confirm the ferromagnetic to a paramagnetism phase transition; however, the non-saturating appearance of M–H curves of all three systems is indicative of high magnetic anisotropy. [ABSTRACT FROM AUTHOR]

In this work, the magnetoelectric composites (1 – x)PbZr0.52Ti0.48O3–xCoFe2O4 ((1 – x)PZT–xCFO) have been synthesized using the combination of sol-gel (for PZT ceramic) and the solid-state (for CFO material) methods. X-ray powder diffraction results and Rietveld refinement have shown that the PZT compound crystallizes in two tetragonal and rhombohedral structures with P4mm and R3m space groups, respectively, while the CFO material has shown a spinel cubic structure with Fd3m space group. The (1 – x)PZT–xCFO composites, for x = 0.10 to 0.50, have been fitted and matched very well to the phases corresponding to PZT and CFO materials. The effect of sintering temperature on the structural and dielectric properties of these composites has been also studied (for x = 0.20). It has been found that the phase is stable for 900°C for 4 h while for 1000 and 1100°C we obtain many secondary phases. On the other hand, the pellet sintered at 900°C shows a low dielectric permittivity value and high relaxation behavior. The scanning electron micrographs (SEM) reveal multigrain agglomerations for all the samples and the grain size is maximal (about 2 µm) for x = 0.10 of CFO content and minimal (about 0.7 µm) for pure CFO. The dielectric properties of the composite samples have been also investigated as a function of temperature and showed one phase transition at 410°C for PZT ceramic. This phase transition has shifted to the lower temperature and present a relaxation phenomenon with the increase of CFO content. The dielectric permittivity decreases with the increase of CFO rate related to the CFO ceramic which has a low dielectric permittivity value. The magnetic properties of these magnetoelectric (ME) composites have been also studied by measuring the magnetization as a function of temperature. The obtained results show one maximum of around 427°C related to the phase transition temperature of CFO. In addition, the magnetization value is found to increase when CFO content increases indicating an intrinsic ME coupling. [ABSTRACT FROM AUTHOR]

The tetraphosphonic acid 1,1,2,2‐tetrakis(4‐phosphonophenyl)ethylene (H8L) was used as linker in the synthesis of eight new isostructural, phosphonate‐based metal‐organic frameworks of composition [M2(H2O)2(H2L)] ⋅ xH2O (M=Y3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+; 1.5