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This study investigates the effect of La³⁺ rare earth ions on the structural, elastic, optical, and radiation shielding features of heavy metal borate glass (B₂O₃-PbO) doped with Cr₂O₃. Density measurements and FT-IR spectra analysis revealed the role of La3+ ions as a network modifier, where successive additions of La 2 O 3 content led to a gradual increase in the density and an increase in the non-bridging oxygen content resulting from the structural transformation between the BO 4 and BO 3 units. The significant improvement in the elastic modulus and microhardness factor moduli was confirmed by calculating the change in ultrasonic velocities through the glassy system. The structural modifications induced by La³⁺ ions narrowed the band gap and increased the Urbach energy, indicating higher disorder within the glass network. The linear refractive indices increased due to increased optical basicity and electronic polarization. Optical absorption results showed that Cr⁶⁺/Cr³⁺ ions occupy octahedral/tetrahedral sites, with the tendency for Cr³⁺ cations to occupy more octahedral sites with increasing La₂O₃ content. The produced samples showed a greenish-yellow color caused by the absorption band centered at ∼415 nm associated with the electronic transition ⁴A₂g(F)→2Eg(G). The ligand field effect highlighted the significance of La³⁺ cations in increasing the crystalline field intensity surrounding Cr³⁺ cations and reducing the nephelauxetic ratio, signifying enhanced covalent character between Cr³⁺ cations and neighboring ions. Moreover, the radiation shielding capabilities of the glassy system were analyzed and compared with standard shielding materials, confirming superior shielding performance in samples with the highest La₂O₃ content. [ABSTRACT FROM AUTHOR]

Ensuring the limited exposure of both patients and medical professionals to radiation during examinations is paramount. One effective approach is the utilization of a film dosimeter that is not only efficient but also easy to carry. In this research, we employed polyvinyl alcohol/nitro blue tetrazolium (PVA/NBT) with varying concentrations of NBT dye (ranging from 0.015 to 0.3 g) to identify the most optimal concentration. These films were subjected to low doses of gamma rays (8, 25, 55 and 96 mGy) emitted from 3 Cs-137 sources. XRF analysis confirmed the effectiveness of the preparation method used, and the NBT salt exhibited excellent solubility (R² = 0.93). The films exhibited an increasing yellow hue as the concentration of NBT dye rose. Following irradiation, they took on a yellowish-brown tint, intensifying with higher gamma doses. PVA/NBT films, when stored in the dark, demonstrated good stability for 30 days post-irradiation. Analysis using ImageJ software unveiled that the relative density of the red color heightened proportionally with the concentration of NBT dye. XRD patterns showcased the clarity of structural rearrangements occurring after irradiation with high NBT concentrations. Two distinct peaks were registered at 2θ = 20.12 and 40.94 °, which shifted to 2θ = 19.74 and 41.30 ° post-gamma irradiation. The CIELab system study and K/S color strength indicated that increasing the NBT dye concentration led to a linear rise in color strength with escalating low gamma doses. Through a comprehensive assessment, it is concluded that PVA/NBT film can be effectively employed as a dosimeter for low gamma doses in diagnostic radiology. [ABSTRACT FROM AUTHOR]

Creating novel nanomaterials with excellent biological behavior and non-toxic is necessary to achieve more efficient treatment. This research aims to prepare metal oxide nanoparticles and evaluate their bioactivity. New Zn(II), Pb(II), and Al(III) coordination polymers were synthesized with the formula [Zn(BDC)(AMPY)(H2O)], [Pb(BDC)(AMPY)(H2O].H2O, and [Al(BDC)(AMPY)Cl)].H2O (BDC = 1,4-benzene dicarboxylate and AMPY = 2-amino-4-methyl pyrimidine), and were used as precursors to prepare ZnO, PbO, and Al2O3 NPs by calcination method, it is a simple technique, inexpensive, and gives better size, shape, high purity, and crystalline. The created compounds were examined by elemental analysis (C.H.N), ultraviolet spectra, IR spectra, Thermal studies, XRD, and electron microscopes (SEM and TEM). The results showed that all coordination polymers exhibit octahedral geometry, react in the ratios (1:1:1) (BDC: M: AMPY), non-electrolyte, and diamagnetic. According to Transmission electron microscopy, the particle size of metal oxide nanoparticles (MONPs) was found to be 50.14 nm for ZnO with rods and near-spherical shape, ∼3 nm for PbO, and 21.12 nm for Al2O3 NPs, both have spherical shapes, these results matched with SEM and XRD. Two species of gram (+v) bacteria, two species of gram (−v) bacteria, and one yeast strain were used to test the antimicrobial effect of MONPs using the agar disk diffusion method. The antioxidant activity of the produced compounds was determined by scavenging DPPH free radicals. Based on the inhibition zone and the DPPH radical scavenging percentage, the prepared metal oxide nanoparticles can be considered antimicrobial and antioxidant agents.

Soft ferrite nanoparticles with the composition Cd 0.4 Zn 0.6-x Co x Fe 1.9 Sm 0.1 O 4 , where x = 0.0, 0.2, 0.4, and 0.6, were effectively prepared using the green synthesis method. The cubic spinel structure of the produced soft ferrite was verified by X-ray diffraction investigation. For the various values of x, it was found that the average crystallite size and lattice constant varied between 34.50 nm and 27.28 nm and 8.5942 Å and 8.4479 Å, respectively. Images from scanning electron microscopy revealed the occurrence of aggregation and fine grain growth. An energy-dispersive X-ray spectroscopy investigation was employed to further confirm the ferrites composition. Tetrahedral absorption bands and metal ion-related absorption modes were found in Fourier-transform infrared spectra. As x changed from 0.0 to 0.6, the optical band gap energy (E g) showed a declining trend from 3.50 eV to 2.57 eV. Additionally, when the quantity of Co2+ increased, the DC electrical resistivity dropped from 5.0475 × 107 Ω cm to 4.3143 × 106 Ω cm. The dielectric characteristics, such as impedance, dielectric losses, and dielectric constant, showed a progressive decline with frequency. Notably, at high frequencies, the specimen Cd 0.4 Zn 0.2 Co 0.4 Fe 1.9 Sm 0.1 O 4 showed the greatest dielectric constant. The behavior of saturation magnetization was growing, and the estimated squareness values (S.Q., or Mr/Ms < 0.5) represent the ability of magneto-static interaction. Based on these characterization results, the synthesized soft ferrites are suitable for use in transformer cores, telecommunications equipment, and microwave devices. [ABSTRACT FROM AUTHOR]

Flexible dye-sensitized solar cells (FDSSCs) have good potential in future photovoltaic technology. The spin coating method deposited the ZnO films on indium-tin-oxide-coated polyethylene terephthalate (ITO-PET) flexible plastic substrates. These films are implanted with Cu-ions with 1 × 1013 ions/cm2, 1 × 1014 ions/cm2, and 1 × 1015 ions/cm2. All the films have a hexagonal structure. The film irradiated with 1 × 1014 ions/cm2 showed high crystallinity and crystallite size. Important optical properties like bandgap energy (E g), band edges, refractive index, extinction coefficient, and dielectric constants are measured by UV–Vis spectroscopy. Bandgap energy decreases, and the refractive index increases at the fluence of Cu ions. The maximum decrease in E g is observed at the 1 × 1014 ions/cm2 dose. Photoluminescence spectra suggest that defects-related emission peaks are decreased at 1 × 1014 ions/cm2 Cu ions fluency. J-V measurements have significantly improved photovoltaic performance compared to pristine ZnO-based solar cells. The highest efficiency (2.30%) is observed at a 1 × 1014 ions/cm2 dose. The efficiency increase is related to improving the charge transfer ratio and shifting the fermi level toward the conduction band. [ABSTRACT FROM AUTHOR]

In this work the effect of gamma irradiation (50 kGy and 100 kGy) on properties of InxSb20-x Ag10Se70 (x= 0,10,20) films has been discussed. X ray diffraction, Transmission Electron Microscopy, Optical properties and Electrical properties have been successfully studied. X Ray diffraction and TEM images reveal the amorphous nature of thin films. A change in the optical energy gap is observed after irradiation. The optical band gap increases accompanied with increase in tailing parameter. The value of N decreases with irradiation dose. It is found that crytallinity is higher for ternary system as compare to quarternary system. From electrical measurements it has been that conduction is in the localised state and the DC activation energy decrease upon gamma irradiations. [ABSTRACT FROM AUTHOR]

Synthesis of lithium borate glass system was carried using the melt quenching technique with varying concentrations of magnesium followed by analysing the different characteristics such as physical, structural, optical and thermoluminescene using various techniques eg. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, and Thermoluminescence (TL). The obtained XRD pattern confirmed the amorphous nature of the prepared samples. Relevant physical parameters have been evaluated to study the response of these properties with respect to magnesium content. The density and molar volume values showed that the network structure changed with increasing magnesium content. It is evident from the FTIR spectra that the network of the prepared samples predominantly contains BO3 and BO4 units. The UV-vis spectra confirmed a decrease in the direct and indirect band gap values with increase in MgO content. Optical parameters namely refractive index, electronic polarizability, reflection loss and dielectric constant were also calculated and found to be in good correlation with other studies. Following gamma rays irradiation with different doses, TL glow curves of prepared glasses were analysed. Deconvolution of TL glow curves was done using glow curve convolution deconvolution (GCCD) function and trapping parameters of isolated peaks viz. activation energy and frequency factor have been determined. [ABSTRACT FROM AUTHOR]

In the last two decades, the scientific community, by the efforts of researchers, has witnessed many attempts to find alternative materials for natural sand using industrial waste materials instead of natural river sand, with a major goal of preserving the natural environmental resources. One of the industrial waste materials, is Used Foundry Sand (UFS), which is processed and used in concrete as a partial replacement for fine aggregate as Treated Used Foundry Sand (TUFS). The precise and all-inclusive investigation on the corrosion resistant characteristics of TUFS blended concrete is very scant. Therefore, experimentations were conducted to study the corrosion resistance performance of TUFS as partial replacements for fine aggregate. TUFS were substituted for fine aggregate in different weight percentages. The reinforced concrete specimens were casted to 5% NaCl under accelerated corrosion process. Apart from half-cell potential measurement, impress current techniques were employed to assess rebar corrosion, and microstructural analysis was carried out using X Ray Diffraction (XRD). According to test results, TUFS concrete has better corrosion resistance qualities than control concrete, paving the way for high-quality concrete production. [ABSTRACT FROM AUTHOR]

Particles derived from combustion processes, mainly composed of soot agglomerates, are acknowledged to be among the main contributors to climate change. Their effects depend mostly on their size, shape, and internal structure. Specifically, the latter has a significant effect on their optical properties, mainly through the refractive index. This index has been widely evaluated, but scarcely correlated with the soot internal characteristics. In this work, relationships between the nanostructural parameters (such as the degree of graphitization, among others) obtained with conventional analytical techniques and the input parameters of the dispersion model (a representation of the electromagnetic radiation through the Lorentz-Drude approach) are proposed with the aim to determine the refractive index. From experiments in a chassis dynamometer, it has been observed that as the vehicle speed increases, the soot samples have, in general, higher degree of graphitization, due to increased combustion temperature. The method proposed allows quantifying how both the real and imaginary parts of the complex refractive index increase as the degree of graphitization increases. Much lower dependence on the average crystal length has been observed. Different combinations of techniques can be used to determine the nanostructural parameters, depending on the analytical technique used. As far as the resulting parameters are reliable, the effect of the technique selected is minor, thus providing flexibility to the application of the method. [Display omitted] • The complex refractive index is affected by the soot nanostructural characteristics. • Structural properties have been related with variables of the dispersion model. • Results from microscopic and spectroscopic techniques can be used as input data. • The real and imaginary parts increase with increasing degree of graphitization. • Higher temperature in the combustion chamber leads to more graphitized soot. [ABSTRACT FROM AUTHOR]

The hard ferrite (CoFe2O4), soft ferrite (Ni0.8Zn0.2Fe2O4) and composite ferrite (CoFe2O4)x/(Ni0.8Zn0.2Fe2O4)1-x (hard/soft ferrite) with x = 0.2,0.4,0.6,0.8 were synthesized by sol-gel auto combustion method. X- Ray Diffraction analysis revealed the formation of the phases. The cubic structures of the samples were confirmed. The thermal analysis done using TGA/DSC confirmed the temperature of phase formation. The FTIR spectroscopy data for the samples were used to confirm the formation of functional groups and successful synthesis of the ferrites. The as-synthesized samples were characterized by SEM confirmed the overlapping spherical particles and elemental mapping was done with EDS. The FESEM and TEM analysis were done for the sample showing enhanced property of magnetic hyperthermia. The saturation magnetization (Ms), Coercivity (Hc) and the remanent magnetization (Mr) of the samples were studied using Vibrating Sample Magnetometry. The surface charge of the particles when dispersed in DI water was examined using Zeta potential measurement. Finally, we analysed the heating characteristics of the samples in an alternating magnetic field of frequency 350 kHz and field amplitude of 50 Oe. It has been concluded that the magnetic properties depend on the concentration of soft and hard ferrite in the samples and magnetic heating efficiency depends on the composition of the samples.

Aluminium alloys and their composites are often used in aerospace, automobile and biomedical applications. However, mechanical and surface properties of those alloys have not reached up to the expectation. This investigation focused to improve the wear resistance properties along with mechanical and surface properties of aluminium matrix composites. Here, novel aluminium matrix nanohybrid composites were developed using titanium oxide and graphite as reinforced via powder metallurgical route. The sintered samples were analysed by different tests such as, hardness, surface roughness, wear tests and other structural analyses. The obtained results showed that some new compounds formed during sintering were responsible for improved mechanical and surface properties for different applications. The wear test showed that there was rapid worn out of graphite from the composites having aluminium content more than 50 wt% due to the higher content of graphite (10 and 20 wt%, respectively). In addition, due to the increase of porosity in the different hybrid composites, there was an increase in coefficient of friction observed in some materials. The aluminium nanohybrid composite having 40 wt% titania and 10 wt% graphite showed best results compared with others. Therefore, the optimized hybrid composites with proper sintering condition would significantly help to get suitable structural, mechanical as well as tribological properties for many advanced applications. [ABSTRACT FROM AUTHOR]

This paper presents a guideline to aid the space group determination of distorted perovskites by a combination of properties, selected area (SAED) and convergent beam electron diffraction (CBED). The case study reported here is based on the (Pb,Ca)TiO3 pseubinary-system. This material represents a combination of polar compound without inversion point (PbTiO3) and incipient-ferroelectric with octahedral tilting (CaTiO3). The practical aspects of each guideline step are: 1) Glazer tilt system determination; 2) lattice type determination; 3) indexing of the diffraction group; 4) point group determination by CBED, optionally combined with analysis of the group-subgroup relationship of the phase diagram compounds and/or the physical properties; 5) observation of the symmetry of systematic absent spots (G-M lines); and 6) matching of the G-M symmetries with the space group possibilities. This work highlights the use of the presented set of characterization to make possible the space group analysis for perovskite polycrystals with tiny distortion.

Sustainable utilization of kaolin has brought benefits to the conservation of mineral resources and economic alternatives to construction materials that rely heavily on commercial Portland cement. Industrially produced water-washed kaolin particles can be thermally activated to meet requirements as supplementary cementitious materials, depending on temperature and duration of calcination. In this study, samples were calcined at temperatures of 600-800°C and durations of 3-4 hours to determine the optimum conditions for the development of metakaolin as supplementary cementitious materials. Using techniques such as PSA, BET, SEM/EDX, FTIR and XRD, water-washed kaolin particles were analyzed and significant differences were observed between the properties of each sample. At 800°C and 3-4 hours, samples were successfully transformed from kaolinite to metakaolinite. This change increased the distribution of multimodal particle sizes, decreased BET surface area, and loss of hexagonal kaolinite morphology. Besides, the weight and atomic percentage of O, Al, Si and K decreased, but C increased. Al-O-H peaks also disappeared, while Si-O peaks were transformed into a single broad peak of amorphous silica. In addition, the kaolinite reflections vanished, but quartz remained. However, complete dehydroxylation of kaolinite was successfully achieved due to increased disorder and defective behavior of samples which were believed to facilitate further transformation into metakaolinite. [ABSTRACT FROM AUTHOR]

Historic areas are at the forefront of global attention because of their historical and social traits that reflect human civilization, giving them an economic weight that helps preserve the city's historical identity. For that, the aim of this paper is based on examining and analyzing the components of a deteriorated stucco window kept in the Restoration Lab of Bab Al-azab Area of the Citadel of Salah al-din Al-ayyubi, which was carried out via different techniques. The stucco window used in this study was inspected using a digital microscope and scanning electron microscope to determine the degradation of the stucco and wooden frame's outside surface. Besides, the polarized microscope involves studying minerals by studying the optical properties of stucco. Also, the light microscope was used to identify the wood. Besides, energy dispersive X-ray (EDX) showed the presence of constituent elements for both the stucco and glass. In addition, X-ray diffraction estimated cellulose crystallinity to decrease. A technique called Fourier transform infrared (FTIR) was also used to find changes in lignin, gypsum, anhydrite, and calcite, as well as cellulose and hemicellulose. A microbiological investigation indicated the presence of a fungal infestation on a wooden frame. This study showed that Salah El-Din Castle's semi-separate historical areas can be considered one of its architectural, planning, and historical models, which have their fabric and characteristics. • A Perforation technique requiring technical skills was used to make this window. • The stucco window was carefully examined and analyzed via different techniques. • Microbiological investigation indicated the presence of a fungal infestation of a wooden frame. [ABSTRACT FROM AUTHOR]

This work reports the obtaining of an anticorrosive pigment composed mainly of hematite (ɑ-Fe2O3) from a powder steel industry waste from rust scale of rebar steel. This residue is mainly composed of Fe2O3 (87.97 %), SiO2 (6.13 %), CaO (1.88 %), Al2O3 (1.30%) and MnO (0.77 %). The total iron oxide of the residue is constituted by the following crystalline phases: magnetite, maghemita, lepidocrocita, wüstite, goethite and hematite. The production of a pigment with a high content of hematite was possible thanks to the high content of precursor iron oxides, which were calcined at different temperatures (750-850 °C) and holding times (0.5-1.50 h). For characterizing the iron content chemically and to identify their iron oxides phases, it was used X-ray fluorescence (XRF) and X-ray diffraction (XRD). The results showed that the pigment with the highest amount of hematite (ɑ-Fe2O3) was obtained at a calcination temperature of 850 °C and a holding time of 1.00 h.

In this paper, the effect of the material and distance of the substrate on the characteristics of gamma alumina nanopowder coated by plasma spray method are investigated. For this purpose alumina nanopowder were coated on the two types of stainless steel and Pyrex glass substrates using a plasma torch. Morphological characteristics of the prepared nanolayer are studied by investigating the scanning electron microscope patterns. Also, the structure and phase changes of deposited alumina are investigated by X-ray diffraction spectrum. The results of this study show that the amount of particles deposition on the steel substrate is more than the glass case. Also, it is shown that by increasing the substrate distance, the amount of particle deposition is decreased for substrates. There is one optimum distance for substrate position with respect to the nozzle exit of the torch for produce and suitable coating and its control. One important result of this experimental study is the phase transfer of alumina from gamma to alpha due to the high temperature of the plasma torch.

A suite of hydrous orthoenstatite crystals were synthesized at 5-7 GPa and 1100-1300 °C, corresponding to the mid upper mantle conditions in continental regions. The synthetic crystals presented a clear, inclusion-free, and euhedral form with a size range from 100 to a few hundred microns. The Al- and water content of crystals were less than 2 wt. % and ranging from ~500 ppm to 1000 ppm, respectively, characterized by Raman and IR spectroscopy, electron microscopy, and SIMS. The analysis shows that the capability of water incorporation for this suite of hydrous orthoenstatite is correlated to the Al-content in the crystal structure. To understand how the detailed crystal structure reflects the influence of water and Al, single crystal X ray diffraction analysis was performed for this suite of hydrous orthoenstatite. By comparing the results obtained at ambient conditions, we find that for low-level of Al-content, <2 wt. %, the Al3+ cation tends to occupy one of tetrahedral sites (TB) only. Analysis of the X ray diffraction results under high pressure indicates that the elasticity of orthoenstatites is insensitive to the presence of low-level water and Al. We use this finding to evaluate the velocity profile at the mid upper mantle of continental regions to compare with seismic observation. The comparison indicates that the cause of the low velocity zone in continental regions originates from the geotherm profile rather than the effect of water on the elasticity of mantle phases. [ABSTRACT FROM AUTHOR]

Introduction: Kṣāra Kalpanā (Ayurvedic alkali formulation) mainly deals with extraction of alkaline material from herb, animals and minerals. Kṣāra preparation mainly has variation in the concentration of Water used for extraction. Objective: To assess the effect of variation in concentration of water and plant part used on the physicochemical parameters of Yavakṣāra (YK). Materials and Methods: YK was prepared by using whole plant with seeds and without seeds. Further these batches were divided depend upon of 4, 6 and 8 times of concentration of water used for extraction. YK was analyzed by using the XRD, AAS-ICP and FTIR. Results: All samples contain Halite crystals of NaCl and Sylvine crystals of KCl. Halite and Sylvine crystals generally formed due to evaporation which is main step in the preparation of Kṣāra Kalpanā. Crystal size of NaCl and KCl is near to nanoparticles (in the range between 90 to 135 nm). YK contains other elements like Fe, Mg and Ca in small amount with slight variance in quantity in different batches. FTIR shows presence of same functional group (C-H of (Alkyl) amines) in all samples of YK. Absences (Pb, As) or traces (Hg) of heavy metal indicate care taken during harvesting and manufacturing. Conclusion: Slight variation is seen in the elements, their concentration and functional group in different batches of YK. Variation in the concentration of water alters the frequency of filtration and affect the period of sedimentation. A batch prepared with less concentration of water (4 times) and without seeds seems to be cost effective.

This study aims to find Geotechnical properties for soil in the Dijlah Area, (7) samples were taken from wells located in the area, according to the size analysis and the plasticity limits tests of that most soils are Silty soil of inorganic low plasticity of the type (ML) and the other sample (CL -ML). The results of chemical analysis showed that the percentage of gypsum ranged between (0.30% - 40.65%) and (T.D.S.) ranged between (56.14%-0.90%) that the high rates cause geometric problems on buildings and structures, While the proportion of organic matter (0.30% -0.95%) and pH values between (7.80–7.9), a somewhat acceptable values. The values of the moisture content of the soils ranged from (0.5% -3.0%) and the presence of gypsum and a collection of sample in the month of September clear effect on those values and may impact adversely on the Voids ratio and compression index, and cause in reducing the values of Cohesion and Internal Friction angle of the soil, Compression index values shown the high compressibility of soil, and the values of the Swelling index indication that the Swelling ratio is low. Soil was evaluated according to the values of the study area (O.C.R.) As excessive consolidation soil . Results showed that the X-ray diffraction test of non-clay minerals are predominant (Calcite, quartz, feldspar) and either clay minerals are (Montmorillonite, Illte, Kaolinite and Palygoroskite ( .

The prominence of spider silk as a hallmark in biomimetics relies not only on its unrivalled mechanical properties, but also on how these properties are the result of a set of original design principles. In this sense, the study of spider silk summarizes most of the main topics relevant to the field and, consequently, offers a nice example on how these topics could be considered in other biomimetic systems. This review is intended to present a selection of some of the essential design principles that underlie the singular microstructure of major ampullate gland silk, as well as to show how the interplay between them leads to the outstanding tensile behavior of spider silk. Following this rationale, the mechanical behavior of the material is analyzed in detail and connected with its main microstructural features, specifically with those derived from the semicrystalline organization of the fibers. Establishing the relationship between mechanical properties and microstructure in spider silk not only offers a vivid image of the paths explored by nature in the search for high performance materials, but is also a valuable guide for the development of new artificial fibers inspired in their natural counterparts.

X-ray powder diffraction studies on the secondary explosive TEX (C 6 H 6 N 4 O 8) in the temperature range 25–150 °C are reported. TEX has a triclinic structure (a = 6.850 Å, b = 7.665 Å, c = 8.826 Å, α = 82.38°, β = 75.0°, and γ = 79.30° at 25 °C), space group P 1 ¯. The crystal structure remains triclinic in this temperature range. From the temperature dependence of lattice parameters we find that thermal expansion is different along different directions. The volume thermal expansion coefficient 17.4 × 10−5 K-1 is comparable to that of a related material, CL-20. Thermal expansion along the c-direction α c is 2.2 times α a and 3 times α b. Phonon frequencies of TEX crystal at different pressures are obtained from density functional theory (DFT) calculations using CASTEP codes. The volume thermal expansion coefficient calculated using Gruneisen formalism is 6.1 × 10−5 K-1. This is the first report on the experimental determination of thermal expansion of TEX, and computation by Gruneisen formalism using DFT. • Volume thermal expansion (α V) of secondary explosive TEX is obtained from temperature dependent x-ray diffraction. • α V is also estimated using Gruneisen formalism from first principles calculations with CASTEP code. • The experimentally obtained α V = 17.4 × 10−5 K-1 is comparable to the computed value of 6.1 × 10−5 K-1. [ABSTRACT FROM AUTHOR]

The influence of two thermal treatments on the structure, morphology, and ultimate properties exhibited by isotactic polypropylene (iPP), synthesized by conventional Ziegler–Natta iPP (Z-iPP) or metallocene iPP (m-iPP) catalysts, has been investigated in the present work. Novelty of this research consisted in the incorporation of a β nucleating agent in two different contents to the m-iPP. Results attained are compared with those found in the Z-iPP and important differences are observed. Differential scanning calorimetry and X-ray diffraction experiments revealed that coexistence of different crystalline lattices took place depending on the type of iPP: β and α forms were found in the β nucleated Z-iPP specimens, whereas α, β, and γ polymorphs could be developed in the m-iPP with nucleating agent. On the other hand, the iPP glass transition temperature (T g) did not exhibit a significant change because of the addition of β nucleant, as deduced from Dynamic Mechanical Thermal Analysis (DMTA) analysis. Moreover, the size and shape of the iPP spherulites was totally changed by the presence of the β agent. This nucleant promoted the formation of smaller spherulites in a greater amount, as demonstrated by optical microscopy. Concerning the mechanical parameters, microhardness, MH, and Young modulus, E, values were in the fast crystallized samples lower than those presented by their slowly cooled counterparts. A good balance in properties was seen for the slowly crystallized m-iPP that incorporated a 5 wt% content in β nucleating agent, this fact being ascribed to the coexistence of the three α, β, and γ polymorphs. [ABSTRACT FROM AUTHOR]

• Chloride ions in exposure solution significantly affected formation of compounds in concrete as indicated by XRD results. • OPC exhibited 4.82 and 2.02 times higher apparent chloride diffusion coefficient than PPC and OPC plus fly ash. • PPC exhibited better performance against corrosion as compared to OPC plus fly ash followed by OPC. • Developed empirical relations for OPC and PPC predicted the I corr with higher degree of accuracy for OPC plus fly ash. • Developed empirical relation between E 0 and I corr predicted well the I corr values reported in literature. This study aims to investigate and correlate durability parameters in concrete exposed to external chloride. Tests for corrosion, chloride diffusion, and X ray diffraction (XRD) analysis were performed. Based on results, ordinary Portland cement (OPC) exhibited 4.82 and 2.02 times higher apparent chloride diffusion coefficient than Portland pozzolana cement (PPC) and OPC plus fly ash. Reinforced concrete specimens made with PPC showed better performance against corrosion as compared to those made with OPC plus fly ash followed by OPC. Concentration of chloride ions in exposure solution significantly affected microstructure of concrete as indicated by formation of compounds from XRD results. Developed empirical relationships between durability parameters for OPC and PPC predicted well the corrosion current density for OPC plus fly ash that was independent of model development. [ABSTRACT FROM AUTHOR]

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This research paper deals with the steel/concrete interface of concrete samples with and without green inhibitor (orange peel extract) and with different two types of superplasticizers (Mapei Dynamon SR 31 and Oxydtron) after an 18 months exposure in aqueous chloride environment. XRD, SEM, and light optical micrograph techniques were applied to investigate the chemical compositions and the spatial distribution of the corrosion products. The experimental results revealed and illustrate that the corrosion products were visible in samples without inhibitor and appeared less noticeable in samples with Mapei Dynamon SR 31 but in the samples with Oxydtron were almost non-existent.

In this study, perovskite films of CH 3 NH 3 PbBr 3 (referred to as MAPbBr 3) doped with varying concentrations of Zr (0%, 2%, and 4%) were synthesized using a sol-gel spin coating technique. X-ray diffraction (XRD) analysis confirmed the retention of the cubic structure in MAPbBr 3 , indicating high crystallinity. Notably, the 2% Zr-doped film exhibited a significantly larger grain size (74 nm). Importantly, the bandgap energy of the 2% Zr-doped MAPbBr 3 film decreased, accompanied by a higher refractive index. Moreover, the conduction band edge of this film closely approached the conduction band edge of the electron transport layer, rendering it promising for solar cell applications. Solar cells were fabricated using the configuration FTO/TiO 2 /MAPbBr 3 /spiro-OMeTAD/Au. Remarkably, the solar cell based on the 2% Zr-doped MAPbBr 3 film demonstrated exceptional performance characteristics: a notably high current density of 9.05 mA/cm2, an open-circuit voltage of 1.034 V, a favorable fill factor of 0.7636, and a remarkable efficiency of 7.15%. Furthermore, impedance analysis indicated that the 2% Zr-doped MAPbBr 3 film exhibited a reduced recombination rate. In conclusion, our study underscores the efficacy of Zr doping in MAPbBr 3 perovskite films, particularly the 2% Zr-doped variant, in enhancing the photovoltaic performance of solar cells. This work opens avenues for further advancements in perovskite solar cell technologies through controlled doping strategies. • Zr-doped MAPbBr 3 films are deposited to FTO-glass substrates using the sol-gel spin coating method. • 2% Zr-doped film has a low Bandgap energy and a large grain size. • EIS showed the recombination resistance is low at 2% Zr doping. • The cell formed with 2% Zr-MAPbBr 3 film has shown highest current density (9.05 mA-cm−2), and efficiency (7.15%). [ABSTRACT FROM AUTHOR]

The manufacture of alloys in solid state has many differences with the conventional melting (casting) process. In the case of high energy milling or mechanical alloying, phase transformations of the raw materials are promoted by a large amount of energy that is introduced by impact with the grinding medium; there is no melting, but the microstructural changes go from microstructural refinement to amorphization in solid state. This work studies the behavior of pure metals (Cu and Ni), and different binary alloys (Cu-Ni and Cu-Zr), under the same milling/mechanical alloying conditions. After high-energy milling, X ray diffraction (XRD) patterns were analyzed to determine changes in the lattice parameter and find both microstrain and crystallite sizes, which were first calculated using the Williamson-Hall (W-H) method and then compared with the transmission electron microscope (TEM) images. Calculations showed a relatively appropriate approach to observations with TEM; however, in general, TEM observations detect heterogeneities, which are not considered for the W-H method. As for results, in the set of pure metals, we show that pure nickel undergoes more microstrain deformations, and is more abrasive than copper (and copper alloys). In binary systems, there was a complete solid solution in the Cu-Ni system and a glass-forming ability for the Cu-Zr, as a function of the Zr content. Mathematical methods cannot be applied when the systems have amorphization because there are no equations representing this process during milling. A general conclusion suggests that, under the same milling conditions, results are very different due to the significant impact of the composition: nickel easily forms a solid solution, while with a higher zirconium content there is a higher degree of glassforming ability.