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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]

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]

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]

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]

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]

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 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]

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]

The decomposition of goethite and goethite/siderite concentrates into hematite with thermal modification was studied through the measurements of X-ray diffraction (XRD), scanning electronic microscope (SEM) and thermal gravimetric analysis (TGA). The experimental results showed that goethite decomposed into hematite directly at around 300°C without any intermediate phase and the decomposition of siderite completed at 500°C. Nanoscale granular structures were observed in the thermally treated products. It deserves highlighting that the decomposition processes proceeded from surfaces into bulks. [ABSTRACT FROM AUTHOR]

Copyright of Material Science & Applied Chemistry is the property of RTU Publishing House 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.)

Composite films of TiN/Ni3N/a-Si3N4were synthesized using the Mather-type plasma focus device with varying numbers of focus deposition shots (5, 15, and 25) at 0° and 10° angular positions. The composition and structural analysis of these films were analyzed by using Rutherford backscattering (RBS) and X-ray diffraction (XRD). Scanning electron microscope and atomic force microscope were used to study the surface morphology of films. XRD patterns confirm the formation of composite TiN/Ni3N/a-Si3N4films. The crystallite size of TiN (200) plane is 11 and 22 nm, respectively, at 0° and 10° angular positions for same 25 focus deposition shots. Impurity levels and thickness were measured using RBS. Scanning electron microscopy results show the formation of net-like structures for multiple focus shots (5, 15, and 25) at angular positions of 0° and 10°. The average surface roughness of the deposited films increases with increasing focus shots. The roughness of the film decreases at higher angle 10° and the films obtained are smoother as compared with the films deposited at 0° angular positions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Effects of O7+ and Ni9+ ion beams on Au–polyaniline composite films. [•] SEM shows the formation of clusters with porous structure after irradiation. [•] The XRD analysis revealed noticeable change in various parameters. [•] Raman spectra show conformational changes after SHI irradiation. [•] Results are discussed on the basis of linear energy transfer of the irradiated ions. [Copyright &y& Elsevier]

Highlights: [•] Spherical shape and 99% purity of biosilica were identified in SEM–EDS. [•] The XRD patterns were analyzed and compared the phase nature of ashes and biosilica. [•] The functional groups of biosilica were recorded by FTIR. [ABSTRACT FROM AUTHOR]

In this paper, we present the result of TiN nanocrystalline deposition on SS316L, using a 4 kJ plasma focus (PF) device for 10, 20, and 30 focus shots. The effect of different number of focus shots on micro-structural changes of thin film is characterized by field emission scanning electron microscope. Existence of grains in different size confirms the formation of TiN nanocrystals on the surface of SS316L substrate. X-ray diffraction (XRD) reveals the formation of a nanocrystalline titanium nitride coating on the surface of SS316L samples. The crystalline size of TiN obtained from XRD data is strongly dependent on the number of focus shots. Thickness of the elements found on the surface of the treated sample that obtain by Rutherford backscattering spectroscopy (RBS) analysis is in the range of 150×1015−200×1015 atoms/cm2. All the existence elements in the coated samples are identified by Particle Induced X-ray Emission (PIXE) spectra. Investigation on the corrosion resistance of TiN coatings was performed using an electrochemical potentiodynamic polarization. Our results suggest that TiN nanocrystalline implantation with proper ion fluences using PF can significantly improve the corrosion resistance of SS316L. [ABSTRACT FROM AUTHOR]

Ba-M- and Sr-M-type hexagonal ferrites have been prepared via a sol–gel route, and the effects of adding different amounts of polyvinyl pyrrolidone (PVP) into the sol solutions. The average crystallite, size, D and σ, was obtained as for Z13 = 22 ± 2 nm and Z13-2 = 16 ± 3 nm and for Z16 = 18 ± 7 nm and Z16-2 = 17 ± 5 nm by XRD. FT-IR and TG analysis were used to prove the presence of PVP on BaFe12O19 and SrFe12O19. Based on the TGA curves the mass losses of the samples are assessed as follows: Z13 ∼15%, Z13-2 ∼25%, Z16 ∼5%, and Z16-2 ∼10%. [ABSTRACT FROM PUBLISHER]

Nanocrystalline particles of lead sulphide and cobalt doped lead sulphide were prepared by a hydrothermal method. The crystalline nature and particle size of the samples were characterized by powder X-ray diffraction analysis (XRD). The thermal stability of nanocrystals was studied by thermo gravimetric analysis (TGA). The morphology of prepared nanocrystals was studied by scanning electron microscope (SEM) and the presence of Co2+ in the sample was confirmed by energy dispersive X-ray analysis (EDX). The formation of the lead sulphide and cobalt doped lead sulphide nanoparticles was analyzed using FTIR analysis. The optical absorption of the synthesized samples was studied using UV absorption spectral analysis. The photoluminescence properties were studied using PL spectral analysis. The degradation of methyl blue (MB) in aqueous medium was studied by using lead sulphide nanoparticles. The cobalt doped lead sulphide works as an efficient photocatalyst for degradation of methyl blue dye. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental investigation on performance of fly ash-based geopolymer pastes at elevated temperature exposure. Geopolymer paste specimens having Si/Al in the range 1.7-2.2, manufactured by activating low calcium fly ash with a mixture of sodium hydroxide and sodium silicate solution were subjected to temperatures up to 900 °C. The effect of Si/Al ratio was studied on the basis of physical appearance, weight losses, residual strength, volumetric shrinkage and water sorptivity at different temperatures. Scanning electron microscopy along with energy dispersive X-ray and X-ray diffraction analysis were also conducted to examine changes in microstructure and mineralogy during the thermal exposure. Specimens gradually changed in colour from grey to light red accompanied by the appearance of small cracks as the temperature was increased to 900 °C. Loss of weight and volumetric strain due to elevated temperature exposure were higher in specimens manufactured with lesser Si/Al ratios. Geopolymer paste specimen containing maximum Si/Al of 2.2 performed best in terms of residual compressive strength after exposure to elevated temperatures. [ABSTRACT FROM AUTHOR]

This paper reports the liquefied petroleum gas (LPG) sensing of titanium dioxide (Qualigens, India). Scanning electron micrographs and X-ray diffraction studies of samples were done. SEM shows that the material is porous and has grapes-like morphology before exposure to the LPG. XRD patterns reveal the crystalline nature of the material. The crystallites sizes of the TiO were found in the range of 30-75 nm. Variations in resistance with exposure of LPG to the sensing element were observed. The average sensitivity for different volume percentages of gas was estimated. The maximum value of average sensitivity was 1·7 for higher vol.% of LPG. Percentage sensor response (%SR) as a function of time was calculated and its maximum value was 45%. Response time of the sensor was 70 s. The sensor was quite sensitive to LPG and results were found reproducible. [ABSTRACT FROM AUTHOR]

Pr3+ and Tm3+ (0.2 mol %) ions doped magnesium calcium bismuth titanate [(MgCa)2 Bi4Ti5O20] ceramics were synthesized by conventional solid state reaction method. The structural and morphological properties of prepared ceramic powders were studied by using XRD and SEM profiles. The elemental analysis and FTIR spectra of the prepared ceramics have been analyzed. Emission spectrum of Pr3+: (MgCa)2Bi4Ti5O20 ceramic powder has shown strong red emission at 614 nm (3P0 → 3H6) with an excitation wavelength λexci = 452 nm (3H4 → 3P2) and Tm3+: (MgCa)2Bi4Ti5O20 ceramic powder has shown blue emission at 477 nm (1G4 → 3H6) with an excitation wavelength λexci = 367 nm (3H6 → 1D2). [ABSTRACT FROM AUTHOR]

In the present work, conventional chemical co-precipitation method was employed for the prepation of Nickel (2,4,6,8&10 at % of Ni) doped CdS nanoparticles. The particle size and lattice parameters for each sample are determined from X-ray diffraction (XRD) analysis. From XRD patterns the broadening of the diffraction peaks indicates the nanostructure nature of the samples. Surface morphology of the samples was studied by Scanning Electron Microscope (SEM). Compositional Elemental analysis of data is obtained from Energy Dispersive Analysis of X-ray (EDAX) plots. [ABSTRACT FROM AUTHOR]

Dry powder method is a solid-state processing technique involving constant milling of the initial compounds for later calcination. This technique was used to prepare the compounds presented in this essay, using TiO2 and MgO in diferentes rates. To analyze the resulting compounds' morphology, Scanning electron microscope (SEM) was used. In the images taken from the TiO2 sample, groups of agglomerations and of grains were found. Nevertheless, it maintains a certain round pattern in both groups, in the shape of micrograins of 0.5-1 µm. SEM images from the MgO sample are typically laminar with barely a few microns of width. The comparative studies of their structural and spectral characteristics through X-ray Diffraction (XRD) confirmed the individual structure of each compound and also, new spectral lines are obtained which suggests that titanates were formed during the process. [ABSTRACT FROM AUTHOR]

Semiconductor ZnS nanoparticles have been successfully synthesized from solutions containing a nonionic surfactant, Triton X-100 (t-octyl-(OCH2CH2)x OH, x = 9,10). The particle size was estimated as 7.7 nm. The optical spectra enabled to conclude that these nanoparticles exhibit quantum size effects. The prepared nanoparticles have been characterized by x-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) and the results are discussed in this paper in detail. [ABSTRACT FROM AUTHOR]

Abstract: The XRD and SEM and TSL studies of the as prepared pure, Cu and Mn doped CaSO4 have been carried out. From the comparative TSL studies it has been seen that the 137°C glow peak of CaSO4:Cu is superior to undoped and Mn doped CaSO4 compounds as well as other Cu doped alkaline earth sulphates. Evaluation of trapping parameters of the most intensive glow peak Cu (0.5mol%) doped CaSO4 is accomplished by a technique named isothermal luminescence decay method and comparison of these parameters with the previously calculated trapping parameters by glow curve shape method (Chen’s method) have been done. It is observed that the most intensive glow peak of Cu doped CaSO4 is found to obey second order kinetics, because of availability of vacant traps for retrapping to take place. Moreover the effect of various doping concentration of Cu on the TSL glow curve and reproducibility of Cu doped CaSO4 has also studied. [Copyright &y& Elsevier]

Coal is an important fuel used in boiler furnaces. There are problems like unburnt coal and solid wastes like ash contain arsenic, selenium, chromium and cadmium while using it. In order to avoid all such difficulties, aluminium metal powder in various grain sizes mixed with pulverized coal and burned. aluminium metal powder is one of the pyrotechnics having higher calorific value and low ignition temperature. The thermal behavior of aluminium powder along with coal is recorded in DTA. The collected ashes were tested in Scanning Electron Microscope and X-Ray Diffraction meter. The SEM results show that coal ash is having granular and regular structure. All the particles have a size range from 5 to 8 μm. On the other hand, the aluminium coal mixture ash shows a fibrous matrix and the particles are irregular. In XRD graph, the peaks in the graph show orientation of atoms in particular plane and angle. The coal ash has a lot of peaks, but the maximum count value reaches only to 340.97. However the value of counts reaches a maximum of 1,539.06 for aluminium ash. This denotes high atom orientation in a single lattice plane. [ABSTRACT FROM AUTHOR]

Mn2+ - doped ZnS nanoparticles were synthesized by a chemical precipitation method at air atmosphere. The synthesis of water-soluble Mn2+- doped ZnS nanocrystals with EDTA as a stabilizer was described. From the peak broadening of the X-ray diffraction, the particle size is found to be 4.5 nm when EDTA was not used as a stabilizer and size is reduced to 3.6 nm with EDTA. The particle size and properties are studied using SEM and photoluminescence. The emission peak of the sample corresponding to photoluminescence is observed at 591 nm. [ABSTRACT FROM AUTHOR]

Nanocrystalline Se0.8Te0.2 films were grown on quartz substrates by using thermal evaporation technique. Structural and optical properties of as-grown and annealed samples were investigated with XRD, SEM and UV-visible spectroscopy. The x-ray diffraction pattern at room temperature shows that the sample are formed in single phase with monoclinic crystal symmetry having space group Cm. Surface morphology of the glass as-grown film was investigated via scanning electron microscopy (SEM). The typical diameter of as-grown nanocrystalline sample is found to be 50 nm, which is consistent with crystallite size calculated by XRD data using Scherrer equation. The UV-visible absorption spectra of the nanocrystals show that the optical band gap of as-grown and annealed samples are situated systematically in the range of 2.10 - 1.95 eV, which is quite larger than the bulk phase of the materials. The results have been explained on the basis of the close interplay between the structural and optical properties. [ABSTRACT FROM AUTHOR]

Abstract: Titanium nitride thin films were deposited on Si(100) substrates by using a low energy (2.3KJ) Mather-type plasma focus device. The composition of the deposited films was characterized by X-ray diffraction (XRD). The crystallite size has strong dependence on the numbers of focus shots. The crystallinity of TiN thin films is found to increase with increasing the number of focus shots. The effect of different number of focus shots on micro structural changes of thin films was characterized by Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM). SEM results showed net-like structure for film deposited for 15 numbers of shots, which are elongated grains of Si3N4 in amorphous form embedded into TiN crystals. The average surface roughness was calculated from AFM images of the thin films. These results indicated that the average surface roughness increased for films deposited with increased number of focus shots. The least crystallite size and roughness are observed for film deposited with 25 focus shots. [Copyright &y& Elsevier]

Abstract: Natural hydroxyapatite has been electrophoretically deposited on medical grade 316L stainless steel. The suspension consisted of isopropyl alcohol and polyethylenimine. The substrates were 16×6×4 mm in dimension. Deposition was achieved on the cathode at 30, 60, and 90 V in 1 to 5 min at constant voltage. After deposition the samples were dried at room temperature for 24 h and deposition weight, roughness, and thickness of the coatings were measured. The coated samples were sintered in a vacuum furnace at 800 °C for 1 h. The surface morphology of the samples was studied by a scanning electron microscope, and phase purity of the coating material was investigated by XRD. The sample coated at 60 V and 3 min led to an adherent, continuous, and crack-free coating. The coating efficiency and thickness increased with increasing deposition time while the slope of the curves decreased which showed a decrease in deposition rate. Also, the current density decreased and yielded to saturation at the constant applied voltage during electrophoretic deposition. Quantitative analysis of the coatings after sintering showed some partial decomposition of natural hydroxyapatite to tricalcium phosphate. Additionally, the experimental results were also compared extensively with the theoretical proposed expressions. [Copyright &y& Elsevier]

Abstract: The present work is an attempt to improve some of the mechanical properties of cemented tungsten carbide (WC) cutting tool by subjecting it to different post treatments. The different post treatments that are tried out to the tungsten carbide–cobalt (WC–Co) inserts are a) controlled cryogenic treatment, b) heating and forced air cooling and c) heating and quenching in oil bath. The response of WC–Co inserts to such different post treatments has been evaluated in terms of microhardness, microstructural changes, scanning electron microscope (SEM) micrograph and Co metal phase changes through XRD. The experimental result indicate a remarkable response to all the above mentioned post treatments and the analysis of the same are presented in this paper. [Copyright &y& Elsevier]

Conducting polypyrrole (PPY) polymer thin films, prepared by the electrochemical process, were irradiated with 50 MeV Li3+ and 90 MeV C6+ ions at different fluences, ranging from 1011 to 1014 ions cm-2. The structural and electrical properties of the swift heavy ions (SHI) irradiated films were analyzed using X-ray diffraction (XRD), Scanning electron microscope (SEM), and conductivity measurement methods. XRD analysis of SHI irradiated PPY films shows that the crystallinity of the PPY films increases with increasing fluences of lithium ions, but tends to become amorphous at higher fluence. Carbon ions irradiations lead to polymer destruction and simultaneous amorphization even at low fluence. The SEM studies of irradiated PPY films show systematic change in their surface morphologies. The surface was smoother at lower fluence but craters were observed at higher fluence. The surface conductivity of films increases with increasing fluence of lithium ions, which also turn to the virgin film conductivity at higher fluence. It was found that carbon ions do not much affect the surface conductivity of PPY. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an experimental investigation into different metallisation structures aimed at reducing the contact resistance and morphology of p-type contacts to 4H-SiC. The structures are based on a combination of Al/Ni and Al/Ti layers. The lowest specific contact resistivity obtained was based on a triple layer Al/Ti/Al contact, measured at 5.0×10−6 Ωcm2. Analogously, for the triple layer contacts comprised of Al/Ni/Al, the lowest specific contact resistivity was measured at 4.9×10−4 Ωcm2. In all cases it was found that the multiple layer structures remained rectifying even after annealing. A range of physical characterisation techniques were used to investigate these different structures. X-ray diffraction (XRD) scans point to enhanced formation of silicides for triple layer contacts based on Al/Ti (Ti3SiC2) and Al/Ni (NiSi x ) when compared to multiple layer contacts. Scanning electron microscope (SEM) and wavelength dispersive analysis (WDA) measurements indicate that a multiple layer metallisation improves the morphology of the contact with respect to the Al spreading, which is known to be problematic during a high temperature anneal. [Copyright &y& Elsevier]

Utilizing scanning electron microscope, X-ray diffraction (XRD) and microhardness tests, we evaluated how various physiological environments affect the hydration behavior and physical properties of mineral trioxide aggregate (MTA). We found that the microstructure of hydrated MTA consists of cubic and needle-like crystals. The former comprised the principal structure of MTA, whereas the later were less prominent and formed in the inter-grain spaces between the cubic crystals. MTA samples were hydrated in distilled water, normal saline, pH 7, and pH 5. However, no needle-like crystals were observed in the pH 5 specimens, and erosion of the cubic crystal surfaces was noted. XRD indicated a peak corresponding to Portlandite, a hydration product of MTA, and the peak decreased noticeably in the pH 5 group. The pH 5 specimens’ microhardness was also significantly weaker compared to the other three groups (p<0.0001). These findings suggest that physiological environmental effects on MTA formation are determined, in part, by environmental pH and the presence of ions. In particular, an acidic environment of pH 5 adversely affects both the physical properties and the hydration behavior of MTA. [Copyright &y& Elsevier]

HoAl-Al2O3/TiAl composites were fabricated by in-situ reaction synthesis using Al, Ti, TiO2 and Ho2O3 powders as raw materials. The effects of Ho2O3 content on the microstructure and mechanical properties of the composites were investigated. The phase constitution and microstructure of the composites were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results indicate that the ultimate phases of the composite are composed of TiAl and Ti3Al (matrix phases), and Al2O3 and HoAl (reinforced phases). Doping Ho2O3 alters the ratio of TiAl and T3Al and the microstructure of the composites, and the properties of the materials were changed accordingly. The mechanical property tests show that the addition of Ho2O3 can improve the properties of composites significantly the bending strength reaches 594 MPa and Vickers hardness reaches 4.76 GPa with 6 wt% Ho2O3. [ABSTRACT FROM AUTHOR]

Abstract: A simple, easy approach to the synthesis of manganese Mn doped zinc sulphide (ZnS) clusters is reported. The synthesis of Mn–ZnS clusters involved mixing and drying of zinc acetate, sodium sulphide and acrylic acid in appropriate ratio and adding Mn at proper conditions. These clusters were trapped in polyacrylic acid (PAA) to form PAA capping to provide stability. The clusters were characterized using high resolution SEM for morphological investigation; XRD for its crystalline nature; photoluminescence (PL) for optical characterization and electrical conductivity measurement. Clusters of Mn–ZnS were formed of the size ~10nm. [Copyright &y& Elsevier]

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]