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The current study demonstrates the effect of Ni-substitution on the structural, dielectric and ferroelectric properties of Ba0.90Sr0.10Ti1-xNixO3 (where x = 0.000, 0.005, 0.015 and 0.025) ceramics, synthesized by solid-state reaction approach. A pure perovskite phase with tetragonal structure has been confirmed by X-ray diffraction (XRD) analysis. Scanning electron microscope (SEM) images revealed change in microstructure. The dielectric behavior of the prepared ceramics was investigated as a function of temperature (30–150°C) at different frequencies. The results indicate that there is an increase in dielectric constant (ϵRT) and low dielectric loss (tanδRT) were obtained at room temperature by substitution of Ni2+ ions in BST ceramics, offering a promising material for capacitor applications at room temperature. Room temperature P-E loops were recorded at different applied electric fields and typical hysteresis loops were obtained. Improvement in the values of Pr and Pmax was observed by substitution of Ni2+ ions. [ABSTRACT FROM AUTHOR]

The economic spray pyrolysis process were used to prepare Zinc oxide thin films. Ahigh - quality thin film is obtained by optimizing factors that include concentration, flow rate, nozzle to substrate distance. The temperature is differed between 350°C to 450°C. The structural and optical qualities were studied through physical investigation. According to XRD, the films have a hexagonal crystal structure. A scanning electron microscope reveals the material's uniform deposition &adhesion across a glass substrate. A direct band gap of about 2.4 to 2.6 eV was obtained for different temperatures. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kufa - Physics is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel Bi-Mg-O composite nano-catalyst was prepared by using Bi(NO3)3 and nano-MgO. Prepared catalyst was characterized using x-ray diffraction (XRD) analysis, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) technique which confirms its nano-crystalline nature and composition. The synthesized novel catalyst Bi-Mg-O was found to be competent catalyst for the synthesis of spirooxindole derivatives by multicomponent reaction of isatin, dimedone, malononitrile and 4H-pyran derivatives by reaction of dimedone, aryl aldehydes and malononitrile using ethanol as solvent at room temperature. The nanocatalyst proved to be recyclable as it is recycled and recovered for three runs without notable loss in catalytic activity. All synthesized derivatives were obtained in exemplary yields. Novel recyclable nanocatalyst, good yields of products, and benign reaction conditions are the noteworthy aspects of the present protocol. [ABSTRACT FROM AUTHOR]

Chloride ions play an important role in the corrosion of bronze through their active reactivity to copper alloys. The corrosion behavior of bronze alloys in NaCl solution was investigated by using X-ray diffraction (XRD), a scanning electron microscope (SEM), and electrochemical tests, with a special emphasis on the corrosion resistance of the α and δ phases in Cu-20 wt%Sn bronze alloys. The experimental results show that the corrosion current density of Cu-20 wt%Sn bronze alloys increases from 1.1 × 10−7 A/cm2 to 2.7 × 10−6 A/cm2 with the increase in the chloride ion concentration from 10−3 mol/L to 1 mol/L. After a soaking duration of 30 days, the matrix corrosion depth reaches 50 μm. The α phase of the alloys is easily corroded in NaCl solution, while the δ phase with high Sn content has strong corrosion resistance. This study provides relevant data for the analysis and protection of ancient bronze alloys. [ABSTRACT FROM AUTHOR]

The contact surface corrosion of friction high-strength bolt (FHSB) joints was analyzed to examine the characteristics of corrosion products and influence factors in steel bridges. Samples were selected from the Dongying Shengli Yellow River Bridge, which has been in service for 33 years. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) were utilized to analyze the microscopic morphology and chemical composition of the corroded surface of the samples. The study identifies that construction quality issues accelerate corrosion of the contact surface and that the contact surface of the aluminum spraying layer transforms from rugged and dense to smooth and porous as corrosion increases. The findings also suggest that the friction coefficient of the FHSB connection node initially decreases and then increases as the corroded surface changes. Corrosion products contained S, Cl, Mn, Si, FeS, and their oxides, indicating that atmospheric, industrial, and Yellow River soil environments contribute to joint corrosion. The study proposes sandblasting and coating the corroded contact surface and deck steel plate with inorganic zinc-rich paint to prevent media penetration and delay substrate corrosion. Adopting ultra-high-performance concrete (UHPC) as the deck structure is also recommended to reduce top plate tensile stress, deck cracking, and media invasion. This study provides insights into the characteristics and mechanisms of FHSB joint corrosion to aid the maintenance, repair, and protection of steel bridges. [ABSTRACT FROM AUTHOR]

In construction Industries, superior fresh and hardened concrete qualities play a significant role in which self-compacting concrete (SCC) is widely introduced. On the other hand, considering the depletion of river sand, manufactured sand (M-sand), created by crushing rock deposits, has been recognized as viable. However, still, there is a lack of understanding of the strength aspect of SCC with M-sand replacement along with admixtures such as Alccofine and silica fume. Therefore, experimental investigations are conducted in SCC by partially and completely replacing river sand with M-sand. Furthermore, to reduce the negative impacts of cement, such as energy consumption and environmental pollution, 10% and 12% pozzolanic materials were added, such as silica fumes and alccofine. Moreover, to examine the impacts on rheological and mechanical properties, EFNARC guidelines were used and measured the compressive strength, impact resistance, bond strength, and flexural and splitting tensile strengths. The test results indicate that incorporating the M-sand as a full replacement in the mix increased the compressive strength by 6.82% for M50 grades of concrete compared to reference SCC after a 28-day curing period. Microstructural analyses such as SEM (Scanning Electron Microscope), EDS (Energy-Dispersive Spectroscopy), XRD (X-ray diffraction), and FTIR (Fourier Transform Infrared Spectroscopy) techniques were also used to study the hydration phase of the M-sand SCC mix when compared to the conventional SCC mix. [ABSTRACT FROM AUTHOR]

This study deals with WC-12Co coatings deposited by cold spraying on 13Cr4Ni steel hydraulic turbine blades. The coatings were deposited under different pressure conditions such as 25, 30, 40 bar at 800 °C, and 50 bar at 900 °C. The microstructural evolution under different pressure conditions and the effect of temperature variation were investigated using a scanning electron microscope (SEM) equipped with energy-dispersive x-ray spectroscopy (EDS) and x-ray diffraction analysis (XRD). In addition, the microhardness analysis of the coatings showed that the WC-12Co coating deposited at 40 bar 800 °C had the highest (270 HV) hardness which was a good attribute for anti-wear applications in hydraulic turbine blades according to most tribological theories. [ABSTRACT FROM AUTHOR]

Nanosized metal oxide dispersed polymer nanocomposites constitute a new class of polymeric materials finds enhanced properties and applications. The present work aims to prepare MgO dispersed polyaniline nanocomposite (MgO/PANI) and also its properties. Insitu chemical oxidative polymerisation method with ammonium per sulphate as an oxidising agent is used for the preparation of PANI/MgO nanocomposites. The reaction was catalysed by hydrochloric acid and also different weight percentage of MgO is maintained with same PANI for different nanocomposites. Structural characterisation of the said composites was carried out by X-ray diffraction tool and the morphology by Scanning Electron microscope (SEM) respectively. AC electrical conductivity of PANI/MgO nanocomposites were well studied and deliberate with the help of equivalent hotness. Further, it demonstrates an corroboration for the transport property of PANI / MgO nanocomposite. Sensor study for the composite is also undertaken with different gases to know its sensing behaviour. [ABSTRACT FROM AUTHOR]

MgMoO 4 with hexagonal particles were prepared by combining high energy ball milling with heat treatment technique. The influence of the mechanochemical activation/heat-treatment on the phase, structural and morphology transformation were investigated by X-ray powder diffraction analysis (XRD), infrared spectroscopy (IR), differential scanning calorimetry (DSC), particle size distribution (PSD) and scanning electron microscope (SEM). Optical properties of the final product were studied by UV–Vis and photoluminescence (PL) measurements. Mechanochemical activation of the initial oxides for 10 h ball milling leads to a full amorphization of MoO 3, only. The heat-treatment at different temperatures after 10 h milling time results to the phase formation of MgMoO 4. The reaction started at 400 °C for 5 h and completed at 800 °C for 5 h. The calculated energy band gap value as prepared MgMoO 4 is 2.03 eV and exhibits photoluminescence emission above 600 nm. The CIE chromaticity coordinates (x = 0.53 and y = 0.43) were found to lie in the orange region. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study aimed to investigate the structure, physical properties, and antifungal activity of ZnTe single-layer, ZnTe/Cu/ZnTe (ZCZ), and ZnTe/Ag/ZnTe (ZAZ) multilayer films. The ZAZ multilayer had the greatest antifungal efficacy, with ZCZ and ZnTe following in descending order of effectiveness. We observed that ZCZ had a MIC of 0.30 mol/ML and that ZAZ had a MIC of 20 mol/L. An X-ray diffraction (XRD) test confirmed a cubic crystal structure for all films, indicating that the crystals were mainly arranged along the (111) plane. For ZnTe films, the average size of crystallites was estimated to be roughly 15 nm, while for ZAZ and ZCZ films, it remained relatively constant at around 14.2 nm and 14.1 nm, respectively. We determined the particle size of ZnTe, ZCZ, and ZAZ using a scanning electron microscope (SEM) and ImageJ analysis. The obtained sizes were 98 nm, 200 nm, and 81 nm for ZnTe, ZCZ, and ZAZ, respectively. We used Swanepoel method and the Cauchy equation to determine the refractive index (n), film thickness (d), and refractive index as a function of wavelength. We used the Tauc equation to find that the optical band gaps (E g) of the films were 1.67 eV for ZnTe, 1.5 eV for ZCZ, and 1.55 eV for ZAZ. We analyzed six new frequency bands found through FTIR analysis. These bands showed important information about the chemical structure of the films. [Display omitted] • ZAZ films have superior antifungal activity. • The Ag middle layer boosts ZAZ composite efficacy. • Enhanced understanding of ZnTe multilayer's antifungal properties. [ABSTRACT FROM AUTHOR]

This study is aimed to investigate laser irradiation effects on the surface, structural, and mechanical properties of iron samples. The prepared samples have been treated for multiple exposure times using continuous-wave diode laser with a wavelength of 532 nm in a laboratory environment. The structural as well as surface modifications of laser exposed targets are explored via scanning electron microscope and X-ray diffractometer. The SEM analysis revealed micrometer grain size, exfoliational sputtering, and crater formation, while XRD patterns were used to investigate d-spacing, and grain size of laser exposed samples. The mechanical characteristics of laser-ablated materials were examined using a micro Vickers hardness-tester, and microhardness has been explored as a function of increasing laser exposure time. It has been observed that grain size reduces while hardness of polycrystalline iron increases with increase in exposure time. [ABSTRACT FROM AUTHOR]

Impact of Swift Heavy Ion (SHI) irradiation is an effective way to tailor the properties of materials to enhance their applicability toward high-end applications. In the present investigation, hydrothermally synthesized Fe-BTC metal-organic frameworks (MOFs) were irradiated with 197Au8+ ion beam, 100 MeV at fluence range of 1×1011 ions/cm² and 1×1012 ions/cm². Hydrothermally synthesized Fe-BTC MOFs were characterized by X-ray diffractometer, UVVisible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), Raman spectroscopy, and Atomic Force Microscopy (AFM). The significant modifications were observed as ion fluence increases, viz. decrease of crystallite size, increase of energy bandgap, reduction in average surface roughness, and the formation of new functional group (C-H) at a higher fluences 1×1012 ions/cm². [ABSTRACT FROM AUTHOR]

Thermal spray coatings are used to improve the erosion resistance of boilers and turbine components for power plants and other industries. In this work, detonation gun spraying method is used to deposit WC-12Co, Stellite 6 and Stellite 21 coatings on SAE213-T12 boiler steel. The coatings were characterized using microhardness tester, scanning electron microscope (SEM), optical microscope and X-ray diffractometer (XRD). The solid particle erosion behaviours of the coatings were evaluated at 30° and 90° impact angles using an air jet erosion test rig. The erosion rates of Stellite 6 and Stellite 21 coatings are found approximately 60% and 50% respectively higher than WC–Co coating, which might be attributed to the respective hardness of the coatings. Cobalt content in the coatings played an important role on the erosion behaviour of the coatings. The erosion mechanisms of the coatings involved micro-ploughing, micro-cutting along with some micro-cracking and hard phase pull-outs. [ABSTRACT FROM AUTHOR]

Abstract 20MO.55Bi 2 O 3.25B 2 O 3 (M = Sr, Ba) glasses have been prepared by conventional melt quenching method and t he Bi 24 B 2 O 39 (boron sillenite) crystalline phase by solid state reaction technique. The effect of variation in wt% of Bi 24 B 2 O 39 crystalline phase on 20SrO.55Bi 2 O 3.25B 2 O 3 (SBB) and 20BaO.55Bi 2 O 3.25B 2 O 3 (BBB) glasses has been investigated. The sintered density of the glass samples were characterized by Archimedes' method. The X-ray Diffraction method, Fourier Transform-Infrared (FT-IR) spectra and FT- Raman spectra are used for structural investigations, whereas Scanning Electron Microscope (SEM) analysis is used for the microstructural study. The effect of the Bi 24 B 2 O 39 crystalline phase as filler in the glass network is confirmed from the FT-IR and FT-Raman spectra. The dielectric properties of the selected samples, analyzed using an Impedance analyzer, show that the dielectric constant slightly increases with increase in the wt% of Bi24B2O39 crystalline phase on glasses and the BBB glasses show higher dielectric values than the SBB glasses. The glass ceramic composites show low sintering temperature (<650 °C), dielectric constant in the range 10–16 and dielectric loss of ~0.0069, suggesting that they can be used as promising candidates for Ultra Low Temperature Cofired Ceramic Applications(ULTCC). Highlights • Effect of Bi 24 B 2 O 39 crystalline phase on 20MO.55Bi2O3.25B2O3 (M=Sr,Ba) glasses were investigated for the first time. • The sintering temperature of glass ceramic composites is <650 °C. • The dielectric constant of glass ceramic composites is in the range 10–16 and dielectric loss is ~0.0069. • These glass ceramic composites are promising candidates for ULTCC Applications. [ABSTRACT FROM AUTHOR]

Potato peel (POPL), an agricultural waste material, obtained from food industry has been used as filler in the powdered form in linear low-density polyethylene (LLDPE) matrix up to 40% (w/w) to prepare biocomposites. The effect of addition of functional polyolefin compatibilizers—maleic anhydride-grafted polypropylene (MA-g-PP) and maleic anhydride-grafted polyethylene (MA-g-LLDPE), up to 5% (w/w) in POPL/LLDPE biocomposites were also studied. Scanning electron microscope was used for morphological characterization and X-ray diffraction for crystallization studies. Tensile strength of LLDPE biocomposites with MA-g-LLDPE compatibilizer reduced only in the range of 12.0-13.4 MPa compared to 14.6 MPa in neat LLDPE, however, reduced up to 40% in LLDPE biocomposites with 40% POPL content. Remarkable improvement in tensile modulus from 75.7 to maximum 703 MPa was achieved among the biocomposites. Mechanical properties of LLDPE biocomposites with 10% (w/w) POPL filler were comparable to neat LLDPE. Addition of maleic anhydride-grafted polyolefins has enhanced flexural strength and flexural modulus of biocomposites with compatibilizers’ up to 128 and 188%, respectively, compared to neat LLDPE. Low values of water absorption were observed for the biocomposites. The study showed that potato peel powder as inexpensive and potentially sustainable filler in the preparation of LLDPE biocomposites which could be biodegradable and environmentally friendly. [ABSTRACT FROM AUTHOR]

Aluminum-based metal matrix composites (AMCs) play a vital role for potential applications in aerospace and automotive industries. This paper explores the experimental analysis of a composite with aluminum LM4 alloy as the matrix and tungsten carbide (WC) as the reinforcement material. The composite specimens were fabricated by the stir casting process. The reinforced ratios of 5, 10 and 15 wt.% of WC particulates were stirred in molten aluminum LM4 alloy (AALM4). Once the composite is solidified, the specimens are prepared to the required ASTM dimensions and tested for various mechanical properties such as tensile strength, impact strength and hardness. Moreover, the tribological behavior of the composite was studied using the pin-on-disc wear test apparatus. X-ray diffraction (XRD) analysis was conducted to analyze the various elements present in the composites. Finally, the scanning electron microscope (SEM) analysis reveals the uniform distribution of WC particles in Aluminum LM4 alloy matrix. The improvement in mechanical properties - hardness, impact strength and tensile strength - was achieved for the increase in the addition of wt.% of WC particles in the LM4 matrix. The decrease in mass loss was observed for the composite containing 15 wt.% of WC during the wear test among the various composites tested. [ABSTRACT FROM AUTHOR]

In 2 S 3 is a III-VI group semiconductor with n-type conductivity and a wide band gap energy, which can be suitable as a buffer layer alternative to CdS in thin film solar cell fabrication. In the present study, In 2 S 3 thin films were grown on glass substrates by the thermal evaporation method at a constant substrate temperature of 200 °C. The deposited layers were post annealed in vacuum in the temperature range of 200–300 °C for 1 h. The grazing incident X-ray diffraction and scanning electron microscopy studies revealed polycrystalline nature of the layers with a good surface morphology. The optical properties of these annealed layers were investigated by using photoacoustic spectroscopy and independently by using conventional optical transmission spectroscopy. The photoacoustic spectra of In 2 S 3 films showed a sharp fall in the photoacoustic signal at photon energies that increased from 1.95 to 2.74 eV with increasing annealing temperature, which corresponds to the band gap energy of corresponding films. The band gap energy and the refractive index values calculated by using photoacoustic spectra are in good agreement with that determined from transmission spectra. [ABSTRACT FROM AUTHOR]

Manganese (Mn) doping of ZnS phosphors was achieved by precipitation method using different ultrasound (US) maturation times. The structural and luminescence properties of the samples were carried out by means of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), photoluminescence (PL), and cathodoluminescence (CL). The real amount of manganese incorporated in ZnS lattice was calculated based on ICP-OES results. According with XRD patterns, the phase structure of ZnS:Mn samples is cubic. EDS spectra reveal deviations of the Mn dopant concentration from the target composition. Both 300 K PL and CL emission spectra of the Mn doped ZnS phosphors display intense orange emission at 590 and 600 nm, respectively, which is characteristic emission of Mn ion corresponding to a 4 T 1 → 6 A 1 transition. Both PL and CL spectra confirmed manganese is substitutionally incorporated into the ZnS host as Mn 2+ . However, it is suggested that the origin of broad blue emission around 400 nm appeared in CL is due to the radiative recombination at deep level defect states in the ZnS. The ultrasound treatment at first enhances the luminescent intensity by ∼3 times in comparison with samples prepared by classical way. This study gives rise to an optimization guideline, which is extremely demanded for the development of new luminescent materials. [ABSTRACT FROM AUTHOR]

Cd-doped ZnO thin films were deposited on a glass substrate via spin coating techniques. The structural properties of the thin film were studied by X-ray diffractometry. X-ray diffraction data showed that the grown films were oriented in (100) direction with hexagonal wurtzite phase. The average calculated grain size ranged from 10 to 12 nm. The lattice constants of the as-prepared ZnO films were calculated using standard formulae, and the values are arrived as a = 3.25 Å and c = 5.20 Å, which confirm the hexagonal of the materials. The Scanning Electron Microscope (SEM) images reveal the polycrystalline structure of pure ZnO film. The minimum thickness is found to be 0.7 µm and the maximum is 1.4 µm. The FT-IR spectroscopy shows some absorption bands at 1427.32 cm−1corresponding to the stretching vibration of C–O band. Various absorption band peaks in the range of 3350–3450 cm−1correspond to O–H species. From the UV spectral analysis, the band gap of ZnO film coated over a glass substrate is found to be 3.4 eV, the band gap of pure ZnO film is calculated as 3.44 eV, and that of Cd-doped ZnO film for 2, 4, and 6 wt% was 3.43, 3.429, and 3.423 eV respectively. [ABSTRACT FROM PUBLISHER]

Metal-sulfides semiconductor nanosheets are talented entrant to be applied in electro-optic devices. Hence, the synthesis of PbS nanosheets is achieved in the current work using a simple route. The synthesized nanosheets were characterized by X-ray diffraction (XRD), FT-Raman, scanning electron microscope (SEM), UV-Visible, Photoluminescence (PL) and impedance spectroscopy techniques. XRD pattern and Raman spectrum confirms the formation of crystalline structure of PbS nanosheets. SEM study shows that the synthesized PbS is well defined nanosheets of <5 nm thicknesses. The absorption band edge is found to be remarkably blue shifted in nanosheets compare to bulk. The energy gap is calculated to be 1.16 eV which is about 3 times superior than the bulk value (0.41 eV). The enhancement of band gap indicates the occurrence of quantum confinement effect in PbS nanosheets. A strong violet emission band at ∼405 nm is observed in PL spectrum which is assigned to electrons transition from conduction-band edge to holes, ensnared at interstitial Pb 2+ sites. [ABSTRACT FROM AUTHOR]

In the present study, polycrystalline Li-Si ferrites with the general chemical formula Li 0.5 + 0.5x Si x Fe 2.5 − 1.5x O 4 , (where; x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) were prepared by high energy ball milling (HEBM) technique. The effect of Si addition on the structure and electrical properties of lithium ferrite were explored. X-ray diffraction analysis indicated that all the samples are formed in cubic spinel structure. The lattice parameter was found to decrease smoothly with increasing silicon content. The average grain size ‘D’ was determined from the scanning electron microscope (SEM) micrographs and it was found to decrease with increasing silicon substitution. In the infrared spectra, two fundamental absorption bands were observed, which are attributed to the intrinsic vibrations of tetrahedral and octahedral complexes, respectively. The wave number of the two bands shifts slightly towards higher frequency side with Si addition. The dc electrical conductivity, studied from room temperature up to 960 K in static air, increases linearly with temperature indicating the semiconducting nature of the samples. The possible mechanism for the influence of silicon substitution on the electrical properties of lithium ferrites was discussed on the basis of the hopping and small polaron models. [ABSTRACT FROM AUTHOR]

Preceramic polymer zirconoborosiloxane was synthesized from the reaction with boric acid, diphenyldiethoxysilane and zirconium (IV) propoxide via solventless process. The thermogravimetric analysis of the polymer showed that ceramic yield as decomposition product at 900 °C was 71%. The pyrolysis of zirconoborosiloxane in an argon gas environment was investigated as standard pyrolytic process up to 1650 °C. Microstructure evolution of ceramic phases was made by means of Fourier transform infrared, Raman spectroscopy, X-ray diffraction and scanning electron microscope analysis. The results clearly demonstrated the pyrolysis products at 1650 °C consist of totally non-oxide ceramic phases of β -SiC, ZrB 2 and free carbon. [ABSTRACT FROM AUTHOR]

This paper highlights a methodology for failure investigation of superheater tubes made of the material T-22 of a coal-based boiler. The process includes visual observation, the identification of sampling locations, the determination of the bulk chemical composition of the base alloy, microstructural investigation using optical microscopy, the exploration of finer structural details using a scanning electron microscope (SEM), the evaluation of hardness over samples obtained from different locations, the fractographic analysis of different failed locations, the X-ray diffraction (XRD) study of corrosion products adhered to inner surfaces, and the determination of the nature of the failure. Within a span of four months, three successive failures of superheater tubes were reported. The tubes were observed to have undergone significant wall thinning. Microscopic examinations using SEM on the failed region and a region some distance away on the as-received tubes were conducted in order to determine the failure mechanism. Layer-wise oxidation corrosion (exfoliation) in the inner surface was observed. Apart from major cracking, a number of nearly straight line crackings were observed in the longitudinal direction of both tubes. Close to cracking/bulging, void formation/de-cohesion of grain boundary indicated creep deformation under service exploitation. The failure mechanism was identified to be a result of excessive oxidation corrosion along the inside wall to reduce thickness, the spheroidization of alloy carbides and the coarsening of precipitate as well as creep void formation along grain boundary leading to inter-granular cracking with material flow near regions covered with thick scales. Moreover, there was a drastic reduction in bulk hardness of alloy and finally 'thin lip fish mouth' fractures. [ABSTRACT FROM AUTHOR]

The pure and Zn-doped SnO 2 nanoparticles were prepared successfully by hydrothermal route on large scale having different doping concentration of zinc from 0 to 0.20%. The calcined nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) for structural and morphological studies. XRD analyses reveal that the nanoparticles of these doping concentrations are polycrystalline in nature and existed as tetragonal rutile structure, SEM study of images confirms the existence of very small, homogeneously distributed, and spherical nanoparticles. The particles size of the nanoparticles was calculated by Scherrer formula and was found in the range of 9–21 nm. The presence of dopant (i.e. zinc) and formation of Sn–O phase and hydrous nature of Zn-doped SnO 2 nanoparticles are confirmed by EDX and FTIR study. The gas sensing properties of pure and Zn-doped SnO 2 nanoparticles were investigated for various concentrations of methanol, ethanol and acetone at different operating temperatures and it has been found that with doping concentration of zinc (x = 0.20%) shows the maximum response 78% to methanol, 65% to ethanol and 62% to acetone respectively at different operating temperature within the measurement limit for a concentration of 100 ppm of each gases. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the structure of Gd 2 O 3 nanoparticles by X-ray diffraction between 25 °C and 1000 °C and compare it with the bulk sample. For the nanoparticles at room temperature, the structure was monoclinic; with an increase in temperature, mixed phases containing the monoclinic and cubic phases were observe between 500 °C and 1000 °C, whereas the bulk sample was transformed from cubic (at room temperature) into hexagonal structures at high pressure. The trends observed for nanoparticles and bulk materials may be different. The scanning electron microscope (SEM) analyses confirmed the existence of Gd 2 O 3 nanoparticles. Moreover, since this material has the magnetic properties, especially during the phase transition, so it was one of the point of our attention in this paper. [ABSTRACT FROM AUTHOR]

The aim of this paper is to examine and analyze a wooden face that was covered with a transparent layer of wax after finishing the mask. The use of wax and encaustic painting was used in Ancient Egypt during the Greco - Roman period, but it was an extremely rare technique in the Egyptian dynasties. The wooden face that was chosen for this study was carefully examined using light microscopy to identify the wood, which proved to be native sycomore fig (Ficus sycomorus). Digital microscope and Scanning Electron Microscope (SEM) were used to assess decay of the outer exposed surface that had been covered in the past with a preparation layer composed of calcium carbonate. SEM micrographs showed clear decay of the cell walls due to the penetration of both the preparation layer and fungal hyphae. Microbiological investigation indicated the presence a bacterial and fungal infestation. The wood was infected infected by Aspergillus niger and Ulocladium sp fungi and Pediococcus dextrinicus bacteria. Further assessment was done by X- Ray Diffraction (XRD) to calculate the decrease of cellulose crystallinity according to Segal and Fourier Transform spectroscopy (FTIR) to detect the changes of the main wood components (cellulose, hemicellulose, lignin). [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the microsegregation and precipitates formed due to segregation in Inconel 625 arc weld overlay coatings on boiler pipes. Examination of microsegregation and precipitates were carried out by means of a scanning electron microscope (SEM) equipped with an EDS detector as well as a transmission electron microscope (TEM) equipped with a HAADF (STEM) and an EDS detectors. The presence of precipitations in the weld overlay was also confirmed with X-ray diffraction analysis (XRD) of residue in the form of powder that remained after the electrolytic dissolution of weld overlay matrix. The investigations showed that the interdendritic regions were considerably enriched during microsegregation with Nb, and less so with Mo. The distribution of Cr and Fe in the weld overlay is relatively uniform. The value of the partition coefficient k for Mo and Nb is lower than 1. Therefore, these elements segregate during solidification into the liquid and, once solidification is finished, the interdendritic regions are considerably enriched with these elements. The value of k for Cr, Ni and Fe are only slightly higher than 1. Though the Inconel 625 is a solid-solution strengthened alloy, precipitation of secondary phases occurs in weld overlays. Precipitations were identified as a Laves phase and carbonitrides (Nb, Ti)(C, N). [ABSTRACT FROM AUTHOR]

Physical aspects of tobacco samples, used in some commonly available Indian brands of cigarettes, with emphasis on their magnetic characterization before and after they get burnt into ashes, are described. The present work highlights the ultrafine nature of the cigarette ashes and provides a compositional insight of their constituent particulate matters as revealed by the XRD and SEM studies. Based on the EDX spectra, elemental distributions of different tobacco samples, before and after they get burnt, are presented. In this work, magnetic measurements of the un-burnt tobacco samples are reported. An attempt is made to shed light on the origin of magnetism observed in these samples. [ABSTRACT FROM AUTHOR]

In this work, the influence of starch on the structure, and consequently, the properties of manganese oxide have been investigated at room temperature. Different weights of starch have been added to manganese nitrate during a solid-state combustion process. All the samples have been annealed at 600 °C for 2 h. The XRD (X-ray diffraction) and FT (Fourier transform)-Raman spectroscopy have shown the formation of α -Mn 2 O 3 cubic structure for weight ratio equal to or less than (1/5) of starch/ Mn(NO 3) 2 , while above this amount the phase changed to tetragonal phase Mn 3 O 4. The crystallite size calculated via the Scherer equation is ranged from 21.3 nm to 23.8 nm. The strain and the dislocation density have values in the order of 10−3. SEM (Scanning Electron Microscope) indicates a discrepancy in the size and the form of the particles due to the effect of starch weights. The sizes of spherical nanoparticles vary in the range of 780 nm - 30 nm. The energy gap estimated from the theory of Kubelka-Munk is reduced from 3.45 eV to 1.75 eV due to the effect of 0 and 0.5/5 ratio of starch/ Mn(NO 3) 2 and increased again to 2.63 eV for Mn 3 O 4. Also, the dielectric permittivity has been influenced by starch weight. The electrical conductivity depends on the frequency and complies with the universal power law of Jonscher. Mn 3 O 4 nanoparticles have been synthesized at low temperatures with a high percentage of low-cost starch with improved characteristics. Therefore, it is a promising material for the production of lithium manganese oxide to be employed in batteries of lithium. [ABSTRACT FROM AUTHOR]

SEM images for GO-PbI 2 nanocomposite, switching behaviour and specific detectivity of the fabricated photodetector. • For the first time, the facile microwave synthesis of GO doped PbI 2 nanoparticles are reported. • X-ray diffraction and FT-Raman studies confirm the formation of GO-PbI 2. • SEM studies confirms morphology in terms of nanoparticles decorated GO nanosheets. • The optical band gap was found to be reduced by Go doping however, still higher than bulk due to confinement effect. • Photoconductivity analysis shows GO-PbI 2 has good photodetector stability and reversibility. Herein, lead iodide (PbI 2) nanorods/graphene oxide (GO) nanocomposites have been successfully achieved at low temperature via microwave-assisted syntheses route. The X-ray diffraction (XRD) analysis confirm good crystallinity and absence of any impurity in the prepared hybrid nanostructures which further confirmed through Raman analysis. The XRD and Raman study also confirm the doping of GO in 2H polytypic PbI 2 structure. The average crystallite size of PbI 2 is calculated to be 20 nm which found to be increased to 53 nm in the case of GO-PbI 2 for high intensity peak. Scanning electron microscope (SEM) images reveal that the GO sheets are decorated with PbI 2 nanoparticles and nanorods. The absorption spectra of PbI 2 was found to broaden whereas energy bandgap of GO-PbI 2 decreases to 2.83 eV in compare to 3.24 eV for PbI 2. The effect of graphene oxide doping on photodetector performance of PbI 2 was elucidated by measuring the I-V characteristics under 532 nm laser light illumination. The pure PbI 2 exhibits a stable and reversible photodetector performance with responsivity of 0.060 AW−1, detectivity of 6.38 × 1010 Jones, EQE of ∼14 % and response time of 224 ms. For GO-doped PbI 2 , these parameters were found to be improved to 0.182 AW−1, 1.79 × 1011 Jones, ∼42 %, and 128 ms, respectively. [ABSTRACT FROM AUTHOR]

The chemically architectured alloys were proposed as a new concept of microstructure, with a multi-scale architecturation. They are composed of a solid-solution at the atomic scale, grain boundaries and composition gradients at the micronic scale and finally a 3D network of gradients at the mesoscale. Composition gradients are between two phases with the same crystalline structure but different compositions. As a first application of this concept, powders of pure Ni and CoCrFeMnNi high entropy alloy were successfully densified by Spark Plasma Sintering. Then the microstructure and mechanical properties were characterized by scanning electron microscope coupled with energy dispersive spectroscopy and electron backscattered diffraction, X-ray diffraction, nanoindentation and compression tests. The obtained chemically architectured alloys present a homogeneous distribution of the two phases with a 10 μm wide chemical gradient in between. By comparison with reference non architectured materials, the chemical architecturation induces a 35% increase of the yield strength. Thus the concept of chemically architectured metallic alloys and composition gradients was proven as very promising: processing of this complex microstructure is possible and it induces a significant mechanical strengthening. Image 1 • A mixture of CoCrFeMnNi and Ni powders was fully densified by spark plasma sintering. • A chemical gradient of around 10 μm was formed between HEA and Ni phases. • This material is called a chemically architectured alloy. • Mechanical strength is improved compared to an ideal mixture of Ni and CoCrFeMnNi. [ABSTRACT FROM AUTHOR]

In this study, undoped and Ag-doped HfO2 thin films were deposited on glass substrates by means of sol–gel dip coating method. These films were then thermally annealed at 500 °C for 1 h. The structural and optical properties of undoped and Ag-doped HfO2 thin films were characterized by X-ray diffraction, UV–Vis spectrometry and scanning electron microscope. The results of this analysis were compared and interpreted with the results obtained in literature by various methods of coating with HfO2. The X-ray diffraction peaks of the films paired with monoclinic HfO2 crystalline peaks. The refractive indices of the films decreased with doping Ag, at 500 nm wavelengths. The optical band gap values of Ag-doped HfO2 thin films increased with doping Ag. The porous structures were observed on the surface films, especially with 5% Ag doping. [ABSTRACT FROM AUTHOR]

Three different forms of Cu powder particles obtained by either galvanostatic electrolysis or a non-electrolytic method were analyzed by a scanning electron microscope (SEM), X-ray diffraction (XRD) and particle size distribution (PSD). Electrolytic procedures were performed under different hydrogen evolution conditions, leading to the formation of either 3D branched dendrites or disperse cauliflower-like particles. The third type of particles were compact agglomerates of the Cu grains, whose structural characteristics indicated that they were formed by a non-electrolytic method. Unlike the sharp tips that characterize the usual form of Cu dendrites, the ends of both the trunk and branches were globules in the formed dendrites, indicating that a novel type of Cu dendrites was formed in this investigation. Although the macro structures of the particles were extremely varied, they had very similar micro structures because they were constructed by spherical grains. The Cu crystallites were randomly oriented in the dendrites and compact agglomerates of the Cu grains, while the disperse cauliflower-like particles showed (220) and (311) preferred orientation. This indicates that the applied current density affects not only the morphology of the particles, but also their crystal structure. The best performance, defined by the largest specific surface area and the smallest particle size, was by the galvanostatically produced powder consisting of disperse cauliflower-like particles. [ABSTRACT FROM AUTHOR]

Blast furnace slag (BFS) is often used as a cement-based raw material for underground filling and surface cemented paste discharge of tailings during mining processes. This paper studied a new cement-based material (NCM) with BFS to replace ordinary Portland cement (OPC). A uniaxial compressive strength (UCS) experiment was used to test the mechanical strength of samples; X-ray diffraction and thermal gravity experiments were used to test the crystalline phases and amount of hydration products by samples; a scanning electron microscope experiment was used to observe the influence of the hydration products morphology by samples; mercury intrusion porosimetry experiment was used to analyze the pore size distribution of samples. The samples with NCM had an optimum UCS; the crystalline phases of the hydration products were similar in OPC and NCM. However, the amount of product formed in OPC was less than that in NCM at the same curing time; more ettringite and calcium silicate hydrate were produced in samples with NCM, which filled the pores and enhanced the UCS of the samples. The final mercury intrusion volume of the samples with NCM were lower than the samples with OPC at the same curing time, which showed that samples with NCM had lower porosities. For the samples with NCM and OPC cured from 7 days to 28 days, the mercury intrusion volume was reduced by 18% and 13%, and the most common pore size of the samples reduced by 53% and 29%, respectively. This showed after 21 days curing time, the pores of all the samples getting smaller; however, the samples with NCM were more compact. The main ingredients of the NCM were clinker, lime, gypsum and BFS, and its ratio was 14:6:10:70. The content of additives to NCM was 0.4%, and the ratio of sodium sulfate: alum: sodium fluorosilicate was 2:1:1. [ABSTRACT FROM AUTHOR]