Energy Dispersive X-ray Spectral Analysis Research Articles

Thermoelectric, mechanical and electrochemical properties of pure single-phase FeSb

This study primarily focused on forming pure single-phase FeSb and explored its thermoelectric, mechanical, and electrochemical properties since no reports are available. The FeSb binary alloy has been synthesized through the vacuum melting method, and the phase formation has been confirmed through powder X-ray diffraction (PXRD). The PXRD results show that the synthesized FeSb binary alloy belongs to the hexagonal crystal structure with space group P63/mmc, which coincides with ICSD no. 53971. The pure single phase has been formed by creating a deficiency of 10 % in antimony. The High-Resolution Scanning Electron Microscopy (HR-SEM) and Energy Dispersive X-ray (EDX) analysis have been used to identify the pure single-phase and various elemental components of the hot-pressed pellet of FeSb0.9. The atomic wt.% of iron (Fe) and antimony (Sb) have been identified through EDX spectral analysis. The highest Seebeck coefficient value of −5.4 μV/K is achieved at 497 K, and the lowest electrical conductivity value of 24049 S/m is achieved at 447 K. The hardness of the material is found to be 6.076 GPa, which is much more sufficient for thermoelectric material during industrial handling. The magnetic characteristics of the prepared pure phase FeSb compound have also been measured by Vibrating Scanning Magnetometer (VSM) analysis, which has a weak ferromagnetic nature. Furthermore, three electrodes were employed to study the electrochemical properties, and the alloy has attained the appreciable specific capacitance of 169.5 F/g at 2 A/g.

Combinatorial Synthesis of AlTiN Thin Films

Nitrides of aluminum (Al) and titanium (Ti) mixtures have long been studied and used as commercial coatings because of their high hardness and high oxidation resistance due to the formation of an alumina layer on the coating surface. To fully understand the contribution of Al and Ti to the properties of the film, a combinatorial deposition approach was employed using half-disk targets. Film growth was carried out using a magnetron sputtering system powered by a 13.56 MHz radio frequency power supply with varying argon (Ar) and nitrogen (N2) gas ratios. Depending on the location of the substrate relative to the target, atomic percent gradients of 0.60–0.70 Al and 0.30–0.40 Ti across the substrate surface were obtained from energy dispersive X-ray spectral analysis. X-ray diffraction peaks at 43.59°, 74.71° (face-centered cubic), and 50.60° (wurtzite) confirmed the presence of aluminum titanium nitride (AlTiN) mixtures, with an increasing amount of wurtzite phase at higher Al concentrations. For all samples, cauliflower-like nanograins were obtained and samples of the 80:20 Ar:N2 gas pressure ratio showed the smallest grain size among the three gas ratio combinations. The 80:20 Ar:N2 films revealed a relatively high hardness compared to the other gas ratios. All thin films exhibited good adhesion to 304 stainless steel substrates.

The Effects of Electron Beam Irradiation on the Morphological and Physicochemical Properties of Magnesium-Doped Hydroxyapatite/Chitosan Composite Coatings.

This work reports on the influence of 5 MeV electron beam radiations on the morphological features and chemical structure of magnesium-doped hydroxyapatite/chitosan composite coatings generated by the magnetron sputtering technique. The exposure to ionizing radiation in a linear electron accelerator dedicated to medical use has been performed in a controllable manner by delivering up to 50 Gy radiation dose in fractions of 2 Gy radiation dose per 40 s. After the irradiation with electron beams, the surface of layers became nano-size structured. The partial detachment of irradiated layers from the substrates has been revealed only after visualizing their cross sections by scanning electron microscopy. The energy dispersive X-ray spectral analysis of layer cross-sections indicated that the distribution of chemical elements in the samples depends on the radiation dose. The X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and X-ray diffraction analysis have shown that the physicochemical processes induced by the ionizing radiation in the magnesium doped hydroxyapatite/chitosan composite coatings do not alter the apatite structure, and Mg remains bonded with the phosphate groups.

ASR mitigation using binary and ternary blends with waste glass powder

Alkali silica reaction (ASR), commonly referred to as “concrete cancer”, is a major durability problem in concrete structures. ASR is a chemical reaction that occurs between the reactive amorphous silica from the natural aggregates and the alkalis in cement in the presence of moisture. This reaction causes undue expansion and cracks in hardened concrete which over time results in deterioration. The use of supplementary cementitious materials (SCMs) has been proven effective to minimize ASR distress. In this study, a synergistic function of glass powder was evaluated in binary and ternary blends with conventional SCMs (slag and silica fume) for ASR mitigation. The ASR mitigation was evaluated using the accelerated mortar bar test (AMBT) and miniature concrete prism test (MCPT) methods. Additional testing including the flow test, strength activity index (SAI), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy-dispersive x-ray spectral analysis (EDS) was conducted to examine the pozzolanic activity, microstructural analysis, and chemical composition. The results demonstrated that the use of SCMs along with glass powder reduce ASR expansion substantially. The binary or ternary blends of 20% replacement of glass powder, slag, or silica fume can be utilized for ASR mitigation without compromising other concrete properties. Also, the ternary system containing glass powder with other conventional SCMs performed better compared to individual use of SCMs to mitigate ASR. These results were also supported by the findings of the microstructure and chemical analysis, in which the glass powder and SCMs were found to reduce the cracks due to ASR expansion.

Phytosynthetic Fabrication of Lanthanum Ion-Doped Nickel Oxide Nanoparticles Using Sesbania grandiflora Leaf Extract and Their Anti-Microbial Properties

Over the past few years, the photogenic fabrication of metal oxide nanoparticles has attracted considerable attention, owing to the simple, eco-friendly, and non-toxic procedure. Herein, we fabricated NiO nanoparticles and altered their optical properties by doping with a rare earth element (lanthanum) using Sesbania grandiflora broth for antibacterial applications. The doping of lanthanum with NiO was systematically studied. The optical properties of the prepared nanomaterials were investigated through UV-Vis diffuse reflectance spectra (UV-DRS) analysis, and their structures were studied using X-ray diffraction analysis. The morphological features of the prepared nanomaterials were examined by scanning electron microscopy and transmission electron microscopy, their elemental structure was analyzed by energy-dispersive X-ray spectral analysis, and their oxidation states were analyzed by X-ray photoelectron spectroscopy. Furthermore, the antibacterial action of NiO and La-doped NiO nanoparticles was studied by the zone of inhibition method for Gram-negative and Gram-positive bacterial strains such as Escherichia coli and Bacillus sublitis. It was evident from the obtained results that the optimized compound NiOLa-04 performed better than the other prepared compounds. To the best of our knowledge, this is the first report on the phytosynthetic fabrication of rare-earth ion Lanthanum (La3+)-doped Nickel Oxide (NiO) nanoparticles and their anti-microbial studies.

Use of energy dispersive X-ray spectral analysis in a scanning electron microscope system to evaluate the mineral composition of grain bread

The concentration of 18 basic elements (in% by weight) contained in the morphological parts of wheat, rye and triticale grains was studied. It is established that the nature of the distribution of micronutrients is determined by their biological role. The elements are part of enzymes: manganese, iron and zinc prevail in the nucleus. Phosphorus, potassium, magnesium are found in greater quantity in the vital layer of aleurone. Cobalt, nickel, aluminum, calcium, chromium, copper, selenium and cadmium dominate the grain surface. The largest amount of mineral elements in the grain is concentrated in the seed. The distribution of metals in triticale grains is characterized by characteristic patterns of wheat and rye. In the distribution of mineral elements in wheat, rye and triticale grains, differences are observed, which are explained by the specific characteristics of these plants. From the grain studied, cereal bread was prepared unmatched on a thick grain leaven. The analysis of the mineral content of the grain bread showed that it was enriched with all major biogenic mineral elements and contained toxic metals (lead and cadmium) in a quantity not exceeding the CMP. A strong negative correlation has been established between levels of certain biological and toxic elements in grain and in pain. The revealed relationship indicates the possibility of switching from dispersive X-ray spectroscopy in a scanning electron microscope system to predict the quality and safety of grain pain, particularly for predicting of the content heavy metals in finished bakery products.

Phase composition of deformable D16 and B95 aluminium alloys with the quantitative assessment of overburning of different stages of development

This paper covers new overburning monitoring methods for D16 and V95 aluminum alloys based on use of a method of an energydispersive X-ray spectral analysis (EDS analysis). It is known that lowered performance of aluminum-based materials is often connected with overburning in their structure. Because the structural changes caused by overburning (flash-off of eutectics and excess low-melting phases and the subsequent crystallization of melted-off microvolumes) are followed by developing porosity, have negative impact on physical and chemical, mechanical and processing properties. The ability to reveal overburning at early stages allows to reject the defective metal. Characteristics sensitive to an early overburning stage are offered based on EDS analysis. A degree of the induced overburning in a D16 sheet is identified. B95 alloy structural components determining the alloy tendency to overburning are revealed. It is found that the EDS analysis makes it possible to reveal changes in the chemical composition of the structural elements of D16 and V95 aluminum alloys and identify an overburning stage quantitatively based on oxygen content. Overburning development leads not only to the higher content of oxygen in the chemical composition of aluminum alloys, but also lowers the electrical conductivity of the material. The paper considers a correlation relationship between the D16 alloy electrical conductivity with overburning induced in it, and oxygen content. The applicability of this method is caused by the method simplicity and a possibility to quantify the defect development in the heat-strengthened deformable aluminum alloys after process heatings. Also this method can be used as an additional research method when metallographic analysis gives no definite answer at identification of early overburning stages.

Phase Composition of D16 and V95 Deformable Aluminum Alloys with the Quantitative Assessment of Metal Burning at Various Stages of Development

New methods to monitor metal burning in D16 and V95 aluminum alloys based on using energy-dispersive X-ray spectral analysis (EDS analysis) are shown. It is known that the reduced properties of aluminum-based materials are often associated with the presence of metal burning in the structure. The structural changes caused by metal burning (partial melting of eutectics and excessive low-melting phases with the subsequent crystallization of molten microvolumes) are often accompanied by the development of porosity and negatively affect the physicochemical, mechanical, and manufacturing properties. The ability to reveal metal burning at early stages makes it possible to reject the defective metal. The characteristics sensitive to the early metal-burning stage are proposed based on the EDS analysis. The induced metal-burning degree in a sheet of the D16 alloy is identified. The structural components of the V95 alloy determining the alloy liability to metal burning are established. It is shown that the EDS analysis makes it possible to reveal the variations in the chemical composition of structural elements of the D16 and V95 aluminum alloys, as well as quantitatively identify the metal-burning stage by the oxygen content. The metal-burning development leads not only to an increase in the oxygen content in the chemical composition of aluminum alloys, but also to a decrease in the electrical conductivity of the material. The correlation between the electrical conductivity of the D16 alloy with induced metal burning and oxygen content is considered. The applicability of the EDS analysis is due to the simplicity of the procedure and the possibility of quantitatively evaluating the development of defects in heat-strengthened deformed aluminum alloys after manufacturing heating. It can be used as an additional method for investigation when metallographic analysis gives an ambiguous answer when revealing early metal-burning stages.

Morphology and properties of ZnO films obtained by repeated spin coating on porous silicon substrates

Layers of porous silicon (PS), multilayered ZnO films, and heterostructures based on them are obtained. The surface morphology, chemical and phase composition of the PS layers and ZnO films, and the transverse cleavage of ZnO–PS nanocomposite, are investigated via energy-dispersive X-ray spectral analysis (EDX), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The current–voltage characteristics of Al/Ag/p-Si(100)/PS/ZnO/Ag/Al and Al/Ag/p-Si(100)/PS/ZnO/SiC/Ag/Al heterostructures are studied.

Investigation of Er3+, Yb3+, Nd3+ doped yttrium calcium oxyborate for photon upconversion applications

In this work, investigation have been done on polycrystalline yttrium calcium oxyborate (YCa4O(BO3)3) for the realization of existence of second harmonic generation and other photon upconversion processes as concurrent effect with the aid of Er, Yb, Nd trivalent lanthanide ions. Pure, Er:Yb co-doped and Er:Yb:Nd triply-doped YCa4O(BO3)3 samples were prepared through solid state reaction and the phase identification has been done using powder X-ray diffraction spectral analysis. FTIR spectra show that the dopants increases the absorption of functional groups and modifies the lattice vibrational modes of YCa4O(BO3)3. The spectral overlap of optical absorption bands of Er3+, Yb3+, Nd3+ ions in 840 nm–1070 nm region indicates the prospect of energy transfer between these ions. The photoluminescence spectrum of Er:Yb:Nd triply doped sample show good enhancement compared to pure and Er:Yb co-doped YCa4O(BO3)3 samples. In the photon upconversion test carried out using 1064 nm Nd:YAG laser YCa4O(BO3)3:Er:Yb:Nd sample produced green light with efficiency higher than the other two samples. Surface morphology of the samples was recorded using field emission scanning electron microscope and analysed. The elemental composition of the samples has been confirmed by energy dispersive X-ray spectral analysis.

Effect of substrate temperature on copper antimony sulphide thin films from thermal evaporation

Copper antimony Sulfide (CAS) thin films were deposited on glass substrate using thermal evaporation technique at different substrate temperatures. Using CuCl2.2H2O, SbCl3 and thiourea as parental materials, the evaporant source material was synthesized by solvothermal method. Moreover, phase identification using X-Ray diffraction was made after the removal of by-products. The CuSbS2 bulk material was pelletized using hydraulic press and used as a target material for developing CAS films on glass substrate with different substrate temperatures such as, Room Temperature (without substrate temperature), 100 °C, 200 °C, 300 °C and 400 °C. The source material and the deposited CAS films were subjected to X-ray diffraction analysis, Raman spectroscopy, Transmission Electron Microscopy, Scanning Electron Microscopy, Atomic Force Microscopy, X-Ray Photo Electron Spectroscopy, Energy Dispersive X-ray Spectral analysis and UV–Vis Spectroscopy. Hall Effect measurement was carried out to investigate, whether the CAS films exhibits p-type conductivity. The deposited films were found to have the band gap in the range of 2.18 eV and 1.62 eV.

Synthesis and characterization of a stable, label-free optical biosensor from TiO2-coated porous silicon

A nanoscale layer of TiO2 is coated on the inner pore walls of a porous silicon (PSi) film by room-temperature infiltration of a TiO2 sol–gel precursor and firing at 500°C. The PSi:TiO2 composite films are characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), energy dispersive X-ray spectral analysis (EDS), scanning electron microscopy (SEM) and reflective interferometric Fourier transform spectroscopy (RIFTS). The analysis indicates that TiO2 conformally coats the inner pore surfaces of the PSi film. The film displays greater aqueous stability in the pH range 2–12 relative to a PSi:SiO2 surface. A label-free optical interference immunosensor based on the TiO2-coated PSi film is demonstrated by real-time monitoring of the physical adsorption of protein A, followed by the specific binding of rabbit anti-sheep immunoglobulin (IgG) and then specific capture of sheep IgG. The time to achieve equilibrium for the physical adsorption of protein A on the surface of TiO2-coated PSi film is significantly greater than that of PSi film. The specificity of the protein A and rabbit anti-sheep IgG construct on the sensor is confirmed by tests with non-binding chicken IgG. The sensitivity of the immunosensor is shown to be 8210±170nm/refractive index unit (RIU).

Laser ablated copper plasmas in liquid and gas ambient

The dynamics of copper ablated plasma plumes generated using laser ablation of copper targets in both liquid (de-ionized water) and gas (air) ambients is reported. Using time and space resolved visible emission spectroscopy (450-650 nm), the plasma plumes parameters are investigated. The electron density (ne) determined using Stark broadening of the Cu I (3d104d1 2D3/2-3d104p1 2P3/2 at 521.8 nm) line is estimated and compared for both plasma plumes. The electron temperature (Te) was estimated using the relative line emission intensities of the neutral copper transitions. Field emission scanning electron microscopy and energy dispersive x-ray spectral analysis of the ablated copper surface indicated abundance of spherical nanoparticles in liquid while those in air are amalgamates of irregular shapes. The nanoparticles suspended in the confining liquid form aggregates and exhibit a surface plasmon resonance at ∼590 nm.

Preparation and Character of Co-Gd Films Electroplated in Urea-Acetamide-NaBr Melt

Abstract The Co-Gd film was prepared in urea-acetamide-NaBr melt at 393 K by an electrodeposition method. The cyclic voltammetry was used to investigate the co-deposition behavior of Gd and Co. Using the techniques, such as scanning electron microscope (SEM), energy-dispersive X-ray spectral analysis (EDS) and X-ray diffraction (XRD), the effects of the cathodic current density on the composition, the surface morphology and the structure of the coating were studied. Results show that the content of Gd in the coating increases at first and decreases later with the increasing current density, and reaches the maximum value of 54.97% (mass fraction, similarly hereinafter) at 12.5 mA/cm2. The surface morphology of the deposit becomes rough with the increase of the content of Gd in the coating. The as-plated deposit consists of amorphous phase, and the deposit is converted into cobalt (Fm3m) phase at 300 °C, and transformed into GdCo5 (P6/mmm) at 600 °C. The magnetic properties of the coating were measured by vibrating sample magnetometer(VSM). The experimental results reveal that the Gd content has great influence on magnetic properties of the alloy films. During heat treatment, the film saturation magnetization come to the maximum value of 550.43 kA/m at 600 °C, and the film coercive force reaches the maximum of 34.97 kA/m at 400 °C.

Mechanism and Microstructure of Electroless Ni-Fe-P Plating on CNTs

Abstract Electroless Ni-Fe-P alloy plating on the surface of CNTs was carried out with a bath using citrate salt and lactic acid as complex agents. We proposed a chemical reaction mechanism. The morphology, structure and chemical composition of the Ni-Fe-P/CNTs were studied with the aid of a scanning electronic microscope (SEM), X-ray diffraction (XRD) and an energy-dispersive X-ray spectral analysis (EDS). The results show that through a correct pre-treatment and electroless plating, Ni-Fe-P/CNTs composite particles can be obtained. The optimum electroless plating parameters of 35–42 °C and pH of 8.5–9.7 were achieved. The as-plated Ni-Fe-P alloy is amorphous. After a heat treatment at 500 °C for 90 min in H 2 , the coating is transformed into crystalloid Ni 3 P, Fe 2 NiP and (Fe, Ni) 3 P. The Ni-Fe-P alloy coating on the surface of CNTs is smooth and unique. The amount of Ni on the surface (mass fraction) of the Ni-Fe-P/CNTs composite particles is 29.13%, that of Fe 3.19% and that of P 2.28%.

Death associated with volatile substance inhalation—Histologic, scanning electron microscopic and energy dispersive X-ray spectral analyses of lung tissue

The investigation of deaths due to the inhalation of volatile substances may be complicated by a lack of scene and autopsy findings. Mechanisms of death may not be determinable at autopsy, and there may be very few markers of inhalant abuse. A 21-year-old man is reported who died from the combined effects of methadone toxicity and toluene inhalation. Histological examination of the lungs revealed congestion and edema, as well as particles of blue, pigmented material within the interstitium and in macrophages. Scanning electron microscopy was undertaken, revealing that the particles contained granules that measured 0.15–0.2 μm in diameter, within the range of mean particle sizes for inorganic paint pigments. Energy dispersive X-ray spectral analysis of the granules demonstrated a significant percentage of titanium (12%) confirming their origin from paint. Ancillary investigations such as electron microscopy and X-ray spectral analysis in cases of possible lethal volatile inhalation may prove useful adjuncts in determining the type of substance inhaled and in providing evidence of previous non-lethal episodes.

A scanning electron microscopy analysis of a spontaneous hemodialysis catheter fracture

Central venous catheters have become increasingly important in hemodialysis treatment. With their increased use, catheter-related problems will be seen more frequently, and more rare complications may be observed. We describe the first case of asymptomatic spontaneous breakdown of a tunneled cuffed silicone catheter used for long-term hemodialysis treatment. This was discovered on removal of the catheter, leaving behind a catheter fragment in the left lower pulmonary lobe. An extensive scanning electron microscopy study showed accumulation of lumps of nonsilicone material at the place of the fracture, leading to severe disruption of the original cross-linked elastomer structure. Using energy-dispersive X-ray spectral analysis, which shows all elements with an atomic number of 11 or greater in a material, we found the lumps were aggregates of barium sulfate particles used to visualize the catheter on fluoroscopy. We suggest that the use of too small or too many barium sulfate particles led to high viscosity of the raw silicone before polymerization, causing improper mixing of barium sulfate particles in the silicone matrix. This resulted in insufficient removal of admixed air bubbles and unequal dispersion of barium sulfate, with the potential for weak spots after extrusion of the silicone into its definitive shape. With the increasing use of hemodialysis catheters for prolonged periods, catheter-related complications related to materials or manufacturing errors can be expected to occur more often. © 2001 by the National Kidney Foundation, Inc.

Elemental Analysis of Environmental Samples by Total Reflection XRay Fluorescence: a Review

A review of total reflection x-ray fluorescence (TXRF) as an effective excitation mode for energy-dispersive x-ray spectral analysis is presented. The instrumental conditions of excitation under grazing incidence (ψ<0.1°) are emphasized and the analytical features of powerful detection and simple and reliable quantification are characterized. The applicability of TXRF to environmental analyses is illustrated by some typical examples. The analysis of pure water samples leads to detection limits at the ppt (ng/l) level. A special matrix separation is only needed for river, sea and waste waters. The analysis of air dust is directly possible with a sampling volume of 1 m3 and a sampling time of 1 h. Organ tissue can be analysed down to the lower ppm range after freeze-cutting of μm thick sections. Plant material has to be pulverized and digested prior to analysis, e.g. with nitric acid. In combination with a chromatographic separation, speciation is made possible for small 0.5 ml fractions, e.g. for vegetable foodstuffs. For all these applications a multi-element determination can be carried out, for about 20–25 elements simultaneously. Simple and reliable quantification is effected by internal standardization. The reliability of the method has been proved by intercomparison tests. Second-generation instruments that are compact and user-friendly are now commercially available.

Elemental Analysis of Environmental Samples by Total Reflection X-Ray Fluorescence: a Review

A review of total reflection x-ray fluorescence (TXRF) as an effective excitation mode for energy-dispersive x-ray spectral analysis is presented. The instrumental conditions of excitation under grazing incidence (ψ < 0.1°) are emphasized and the analytical features of powerful detection and simple and reliable quantification are characterized. The applicability of TXRF to environmental analyses is illustrated by some typical examples. The analysis of pure water samples leads to detection limits at the ppt (ng/l) level. A special matrix separation is only needed for river, sea and waste waters. The analysis of air dust is directly possible with a sampling volume of 1 m 3 and a sampling time of 1 h. Organ tissue can be analysed down to the lower ppm range after freeze-cutting of μm thick sections. Plant material has to be pulverized and digested prior to analysis, e.g. with nitric acid In combination with a chromatographic separation, speciation is made possible for small 0.5 ml fractions, e.g. for vegetable foodstuffs. For all these applications a multi-element determination can be carried out, for about 20-25 elements simultaneously. Simple and reliable quantification is effected by internal standardization. The reliability of the method has been proved by intercomparison tests. Second-generation instruments that are compact and user-friendly are now commercially available.

Interpretation of in situ logging p-wave velocities in sediments over very young crust

Laboratory and downhole logging measurements on sediments in the Lau back arc basin display none of the expected trends in physical and acoustic properties as a function of depth. Insitu, the sediments are underconsolidated, although in the lab the sediments can consolidate normally, as shown by measuring both compressional and shear wave velocity in a controlled laboratory triaxial setting. Both compressional and shear wave velocity, measured in the triaxial cell after consolidation to estimated insitu pressures, are significantly higher than those measured insitu. The primary reason that sediments are not consolidating insitu, and therefore, compressional and shear wave velocity are not decreasing downhole, is that water lost during the consolidation process is rapidly replaced by fluids circulating through the system convectively. The undisturbed microfabrics of these sediments were examined by scanning electron microscopy equipped with energy dispersive x-ray spectral analysis and image analysis systems. This allowed quantitative measurement of pore space and degree (and type) of cementation. In general, compressional and shear wave velocity did not show consistent correlation with grain size distribution. Instead, variations in velocity within lithological units were related to the distribution of pore space and digenetic state of the sediment.