Energy Dispersive Method Research Articles

Analyses of the Structural and the Temperature-Dependent Magnetic Properties of Pine Resin and Pine Bark from the Oltu/Erzurum Region in Turkey

In the present paper, our aim is to investigate the structural, compositional and temperaturedependent magnetic properties of pine resin and pine bark obtained from a yellow pine forest situated in Oltu/Erzurum, a tertiary depositional area, located on the central area of the Northeast Anatolian Fault Zone. With the purpose of understand the regional effects on pine resin and pine bark obtained from a yellow pine forest, electron paramagnetic resonance spectroscopy is used to determine paramagnetic features at different temperatures (room temperature, 65 ◦ C, 75 ◦ C and 85 ◦ C). An X-ray diffraction experiment is performed to obtain the crystalline nature of the resin and the bark. Also, scanning electron microscopy and energy dispersive spectroscopy methods are preferred for analyzing the surface morphology and the elemental composition of the samples, respectively.

Geochemical Peculiarities of Galena and Sphalerite from Polymetallic Deposits of the Dal’negorskii Ore Region (Primorsky Krai, Russia)

New data on the composition of the major minerals from the skarn and vein polymetallic deposits of the Dal’negorskii ore region are reported. Analysis of galena and sphalerite was carried out by the X-ray fluorescent energy-dispersive method of synchrotron radiation for the first time. It is shown that the minor elements in major minerals of different deposits are typomorphic. Among these elements are Fe, Cu, Ni, Cd, Ag, Sn, and Sb, as well as In in sphalerite and Te in galena. The high concentrations of Ag, Cu, Te, Cd, and In in the extracted minerals indicate the complex character of mineralization. The compositional patterns of ore minerals characterize the sequence of mineral formation from the skarn to vein ores, and the sequence of deposits from the mesothermal to epithermal conditions. This provides geochemical evidence for the stage model of the formation of mineralization in the Dal’negorskii ore region.

Effects of aluminum addition on the characteristics of Cu-28Zn brass produced by gravity casting

Brass has an attractive combination of strength, ductility, and good corrosion resistance, which are required in many components, such as cartridge cases, valves, and fittings. In all of these components, brasses are usually fabricated through casting, rolling, deep drawing, and other mechanical deformation processes. Alloying elements were added in order to improve strength without sacrificing the ductility of brass. In this research, aluminium was added to Cu-28Zn brass of 1.9, 5.7, and 6.2 wt. % addition. Alloys were fabricated by gravity casting followed by homogenization at 800 °C for 2 h. Material characterizations were done through microstructural analysis using optical microscope and Scanning Electron Microscope – Energy Dispersive X-Ray (SEM-EDX), Rockwell B and Micro Vickers hardness testing methods, and tensile testing. The results showed that Al addition improved the mechanical properties of Cu-28Zn alloy. Hardness, tensile strength, and yield strength increased, but the elongation decreased.

Residual stress analysis of energy-dispersive diffraction data using a two-detector setup: Part II — Experimental implementation

Based on the theoretical concept of a two-detector setup for the energy-dispersive diffraction method (Apel et al., 2017), the experimental implementation of the proposed measurement concepts is demonstrated. The measurement configurations as well as the formalism for data evaluation introduced in the first part of this series are applied to the analysis of in- and out-of-plane near surface residual stress gradients in mechanically surface treated steel. Diffraction experiments carried out with the Bremsstrahlung of a conventional X-ray tube are shown to yield results with a quality comparable to measurements conducted at a synchrotron beamline. Furthermore, it is demonstrated that the simultaneous measurement of the positive and the negative ψ-branch can partly compensate for the much higher counting times due to the lower photon flux of the X-ray tube. The results are compared and assessed with those obtained by means of synchrotron radiation (beamline EDDI@BESSY II) and the layer removal method (LRM).

The application of chitosan/collagen/hyaluronic acid sponge cross-linked by dialdehyde starch addition as a matrix for calcium phosphate in situ precipitation

Scaffolds based on chitosan, collagen and hyaluronic acid, cross-linked by dialdehyde starch were obtained through the freeze-drying method. The porous structures were used as matrixes for calcium phosphate in situ precipitation. Composites were characterized by different analyses, e.g. infrared spectroscopy, SEM images, porosity, density, and mechanical tests. Moreover, an examination involving the energy dispersive X-ray spectroscopic method was carried out for the calcium and phosphorus ratio determination. In addition, the adhesion and proliferation of human osteosarcoma SaOS-2 cells were examined on the obtained scaffolds.The results showed that the properties of the scaffolds based on chitosan, collagen, and hyaluronic acid can be modified by dialdehyde starch addition. The mechanical parameters (i.e. compressive modulus and maximum compressive force), porosity, and density of the material were improved. Calcium phosphate was deposited in the scaffolds at the Ca/P ratio ∼2. SEM images showed the homogeneous structure, with interconnected pores. The cross-linker addition and an inorganic compound precipitation improved the biocompatibility of the scaffolds. The obtained materials can provide the support required in tissue engineering and regenerative medicine.

Non-Destructive Determination of Residual Stress Depth Profiles of Hybrid Components by Energy Dispersive Residual Stress Measurement

Through the combination of two or more materials to one compound, for example high-strength steel and aluminum, hybrid massive components can be manufactured, whose properties are specially adapted to the respective application. One of the challenges is the joining zone which is influenced by machining induced residual stresses. In order to examine the residual stress modifications by the machining process and in addition to analyze the influence of these residual stress gradients on the lifespan of hybrid components a non-destructive method of measuring depth-resolved residual stress is necessary. Therefore, an innovative energy dispersive X-ray measurement technique is used in the collaborative research center 1153 (CRC 1153). In this study the suitability of the method is examined by comparing the results with the angle dispersive method both in machined front surface of mono materials and hybrid shafts. A parametrical study shows the possibility to get greater depth information by variation of the measuring parameters Bragg angle, tilting angle, collimator and current. In addition, the results of the energy dispersive method combined with electrolytic removal is shown. Based on these results the evaluation of the reliability and reproducibility of energy dispersive residual stress measurements is completed.

Properties of Powders from Stainless and Heat Resistant Alloys Produced by Gas Dynamic Spray for Manufacturing Parts of Complex Shape

The objects of the study were powders of stainless steel and superalloy obtained gas-dynamic spray in the VIGA 2B (ALD, Germany). It have been investigated the microstructure, structural and phase composition, grain size, physical, chemical and technological properties of powders of alloys obtained by gas-dynamic spray melts.To study the structure and properties of powders of different factions were the used electron microscopy techniques, metallographic, sedimentation, X-ray, energy dispersive analysis, imaging, chemical, and other analytical methods. The powders have a spherical shape, low impurity content, good fluidity and can be used for producing parts by selective laser sintering, slip casting, injection molding, coating plasma and the sintering.

An artifact-minimizing method for total dust sampling and chemical characterization of industrial high-temperature aerosols

ABSTRACTConventional methods for total dust sampling from industrial high-temperature aerosols containing condensable species, e.g., in boilers of municipal solid waste incinerators (MSWI), are always influenced by condensation artifacts. Therefore, we extended the scope of a previously developed probe intended for size-fractionated aerosol sampling with reduced artifacts and employed it for total dust measurements. The dust is collected on quartz fiber filters, which are gravimetrically evaluated and chemically analyzed by energy dispersive X-ray spectroscopy and wet-chemical methods. First measurements in the boiler of an MSWI confirm that the probe is also suitable for artifact-minimized total dust sampling. The data are consistent with results from measurements with the size-fractionating method conducted in parallel. By combining the results of both sampling methods, we reveal the average chemical composition of the submicron particles in the aerosol, which is not accessible by one of the two methods...

Dependence of the textural properties and surface species of ZnO photocatalytic materials on the type of precipitating agent used in the hydrothermal synthesis

Three different precipitating agents (NaOH, \(\hbox {NH}_{4}(\hbox {H})\hbox {CO}_{3}\) and \(\hbox {CO}(\hbox {NH}_{2})_{2}\)) have been applied for the hydrothermal synthesis of ZnO powder materials, aiming at obtaining various types of porosity and surface species on ZnO. The synthesis procedures were carried out in the presence and in the absence of tri-block copolymer Pluronic (P123, EO20PO70EO20). These materials were characterized by powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM)–energy-dispersive X-ray spectroscopy (EDX), BET method and TG–differential thermal analysis (DTA) method, and their photocatalytic activities were tested in the removal azo dye Reactive Black 5 (RB5). The urea precipitant yields spongy-like surface forms and the greatest share of mesopores. It has the highest specific surface area, highest degree of crystallinity of wurtzite ZnO phase and largest content of surface OH groups in comparison with the other two precipitants. The zinc hydroxycarbonate intermediate phase is missing in the case of NaOH as precipitating agent; therefore, it manifests poorer textural characteristics. The morphology of P123-modified sample is different and consists of needle-shaped particles. The urea-precipitated samples display superior performance in the photocatalytic oxidation reaction, compared with the other precipitated samples. The other two precipitating agents are inferior in regard to their photocatalytic activity due to greater share of micropores (not well-illuminated inner surface) and different surface morphologies.

Natural fiber reinforced expandable graphite filled composites: Evaluation of the flame retardancy, thermal and mechanical performances

Expandable graphite (EG) weighing 3wt%, 5wt% and 7wt% was incorporated into 20wt% natural fiber (NF) reinforced epoxy and these composites were characterized using Bunsen burner test, bomb calorimeter, thermogravimetric analysis, dynamic mechanical analysis, combined confocal Raman-Atomic Force Microscope, tensile test, scanning electron microscopy and energy dispersive X-ray method. Two formulations with 3wt% and 5wt% EG coating were produced to investigate their flame retardancy in comparison to that of EG filled composites. Increasing EG fillers in the composites significantly improved the fire resistivity and thermal properties, this, however, was found to reduce the mechanical properties. When EG particles were used as intumescent coating, at least 5wt% content of EG was necessary to provide the sufficient self-extinguishing properties. Chemical treatment of the NFs could considerably enhance the mechanical performances. The morphology of composites, graphite particles and their char were investigated.

Determination of Doped Concentrations in ICF Shells by X-Ray Equivalent Absorption

An X-ray equivalent absorption technique is developed to determine the doped concentrations of the inertial confinement fusion shells. Doped atoms in the shells are used to increase the opacity for radiation, to improve the absorptive capacity of the shell wall for X-ray, and to restrain the growth of hydromechanics instability. The doped concentrations in the shells are difficult to determine for the relatively thick shell wall and the spatial resolution. A novel model is proposed to determine the doped concentrations by a theory of X-ray equivalent absorption. The advantage of this model is that optical density (D) and the exposure curve [D = Φ(I)] of film plates are not necessary to calculate the doped concentrations. The model is validated with a thickness error of 2% by the polypropylene step wedge, the aluminum step wedge, and the polystyrene sphere. The error of results for doped concentration between this method and the energy-dispersive spectroscopy method is less than 0.1 at. %. The uncertainty also is analyzed and the combined expanded uncertainty is better than 0.2 at. % for the Ge-doped glow discharge polymer shell (k = 2).

Mechanical and Corrosion Behavior of Al-Zn-Cr Family Alloys

Aluminum base alloys containing chromium (Cr) and zinc (Zn) were produced using extrusion and powder metallurgy techniques. Cr additions ranged between 5 to 10 wt. %, while Zn was added in an amount between 0 and 20 wt. %. Heat treatment processes were performed during powder metallurgy process, at different temperatures, followed by water quenching. Similar alloys were extruded with an extrusion ratio of 4.6 to get proper densification. Optical microscopy was used for microstructure investigations of the alloys investigated. The element distribution microstructure study was carried out using the Energy Dispersive X-ray analysis method. Hardness and tensile properties of the investigated alloys have been examined. Wear resistance tests were carried out and the results were compared with these of the Al-based bulk alloys. Results showed that the aluminum base alloys, containing 10 wt. % Cr and heat treated at 500 °C for one hour followed by water quenching, exhibited the highest wear resistance and better mechanical properties.

Nano-scale chemical evolution in a proton-and neutron-irradiated Zr alloy

Proton-and neutron-irradiated Zircaloy-2 are compared in terms of the nano-scale chemical evolution within second phase particles (SPPs) Zr(Fe,Cr)2 and Zr2(Fe,Ni). This is accomplished through ultra-high spatial resolution scanning transmission electron microscopy and the use of energy-dispersive X-ray spectroscopic methods. Fe-depletion is observed from both SPP types after irradiation with both irradiative species, but is heterogeneous in the case of Zr(Fe,Cr)2, predominantly from the edge region, and homogeneously in the case of Zr2(Fe,Ni). Further, there is evidence of a delay in the dissolution of the Zr2(Fe,Ni) SPP with respect to the Zr(Fe,Cr)2. As such, SPP dissolution results in matrix supersaturation with solute under both irradiative species and proton irradiation is considered well suited to emulate the effects of neutron irradiation in this context. The mechanisms of solute redistribution processes from SPPs and the consequences for irradiation-induced growth phenomena are discussed.

Study of Low Voltage Prebreakdown Sites in Multicrystalline Si Based Cells by the LBIC, EL, and EDS Methods

Breakdown sites in multicrystalline Si solar cells have been studied by reverse-bias electroluminescence, electron beam induced current (EBIC) and laser beam induced current (LBIC), and Energy Dispersive X-Ray Spectroscopy methods. In the breakdown sites revealed by EL at small reverse bias (~5 V), the enhanced aluminum and oxygen concentration is revealed. Such breakdowns can be located inside the depletion region because they are not revealed by the EBIC or LBIC methods. Breakdowns revealed by EL at larger bias correlate well with extended defects in the EBIC and LBIC images.

Supercritical water synthesis of nano-particle catalyst on TiO2 and its application in supercritical water gasification of biomass

ABSTRACTHydrogen production by catalytic gasification in supercritical water (SCW) is a promising way to utilise biomass resource. Supercritical water not only provides homogeneous and rapid reaction environment for the biomass gasification but also causes catalyst agglomeration problems. In order to prepare activity and stable catalyst for biomass gasification in supercritical water, supercritical water synthesis method was utilised and the preparation method was investigated. Ni, Co, Zn and Cu metal elements were loaded on TiO2 particles which was proved to be hythothermally steady in supercritical water. And nano-particles were successfully made. Based on gas chromatography/mass spectrometer (GC/MS), scanning electron microscopy, energy dispersive spectrometer (EDS) and X-ray diffraction analysis methods, it turned out that metal catalysts have a uniform spherical structure with diameter around 30 nm. Metal catalysts synthesised with supercritical hydrothermal method showed certain catalytic effects. Ni catalyst had the best performance in stability while Zn catalyst possessed highest hydrogen yield.

Strength of basalt fibers influenced by thermal and chemical treatments

This paper presents an experimental investigation regarding the influence of the thermal and chemical treatment over the strength of one type industrially used basalt fibers. The fibers are heated at 160℃, 320℃, 480℃, 640℃, or 800℃ using a muffle furnace for 32, 64, 128, or 256 min. In the second series, the fibers are treated with 10% to 30% H2SO4, HCl and NaOH aqueous solutions for 48 h. The strength of the fibers is tested after the different treatments and is found to be decreased even after moderate heating temperatures. The fibers are as well investigated by scanning electron microscopy and energy-dispersive spectroscopy. By energy-dispersive spectroscopic method, the surface composition of the fiber is determined and significant changes in composition are observed even after treatment at 160℃. Obviously the change in surface composition is related to the change in the strength. A possible explanation can be the decomposition of the sizing on the fiber surface.

Electrodeposition of silver on CrTiO2 nanotubes and study of their structural, morphological, optical and photocatalytic properties

CrTiO2 nanotubes were prepared by facile one step anodization of titanium substrate and silver nanoparticles were loaded on prepared nanotubes by electrodeposition. Ag/CrTiO2 samples were characterized by X-ray diffraction, field emission scanning electron microscope, ultraviolet–visible spectroscopy and energy dispersive X-ray spectrometer methods. The degradation of methylene blue (MB) was used as a model reaction to evaluate the photocatalytic activity of the obtained samples. Results indicated that the degradation of MB was enhanced using Ag/CrTiO2 samples. Kinetic research showed that photo degradation process followed the first-order reaction; the apparent reaction rate constant of Ag/CrTiO2 sample was approximately two times higher than that on the bare CrTiO2 sample. After five successive cycles under 600 min visible light irradiation, Ag/CrTiO2 remained highly stable photocatalytic activity. The catalysts prepared in this study exhibit industrially relevant interests due to the low cost and good photocatalytic activity.

Silver nanoparticles decorated titanium dioxide-tungsten trioxide nanotube films with enhanced visible light photo catalytic activity

A simple strategy for synthesizing silver-loaded titanium dioxide-tungsten trioxide nanotubes film for use as recyclable photo catalyst is introduced. Highly ordered and uniformly distributed titanium dioxide-tungsten trioxide nanotubes (WTNTs) on pure titanium were successfully fabricated by one-step electrochemical anodizing and silver deposited on these nanotubes by simple electrochemical method. The as-prepared samples were characterized by X-ray diffraction, field-emission scanning electron microscopy, ultraviolet-visible diffuse reflectance spectroscopy and energy dispersive X-ray spectrometer methods. The degradation of methylene blue (MB) was used as a model reaction to evaluate the photo catalytic activity of the obtained samples. Compared with the pure TiO2 nanotubes (TNTs) and bare WTNTs, the WTNTs decorated with silver (Ag/WTNTs) showed much higher photo catalytic activity in the degradation of MB under visible light irradiation. Under the same condition, no obvious photo degradation of methylene blue was found for pure TiO2 nanotubes. The average photo catalytic degradation efficiency of the Ag/NTNTs obtained for the degradation of MB is 2.3 times higher than those of bare NTNTs. After 6 successive cycles under 720min visible light irradiation, Ag/WTNTs remained highly stable photo catalytic activity. The enhanced photo catalytic activity of ternary Ag/WTNTs photo catalyst was ascribed to improved light absorption, reduced carrier recombination and surface plasmon resonance of Ag nanoparticles. Moreover, the excellent stability and reliability of the Ag/WTNTs photo catalyst demonstrated a promising application for organic pollutant removal from water under visible light irradiation.

Promoting Effect of Co, Cu, Cr and Fe on Activity of Ni-Based Alloys in Catalytic Processing of Chlorinated Hydrocarbons

A series of sponge-like Ni1−xMx (M = Cu, Co, Cr, Fe; x = 0.00–0.10) alloys was prepared via synthetic routes with subsequent reduction in H2 atmosphere at 800–1000 °C. Formation of Ni-based solid solutions with face-cantered cubic (fcc) lattice of nickel was proven by X-ray diffraction analysis for all prepared samples. Ni1−xMx alloys were explored as precursors for self-organizing catalysts active in processing of 1,2-dichloroethane into carbon nanomaterial (CNM). According to kinetic studies of CNM growth performed at 600 °C, the catalytic activity of Ni1−xMx samples changes as follows: Cr > Co–Cu ≫ Fe. Ni–Cr sample showed rather stable performance during 4 h whereas Ni–Co, Ni–Cu and Ni (reference) samples underwent rapid deactivation after ~150 min of reaction. The presence of the residual amount of Cr (0.5 at.%) found by energy dispersive X-ray microanalysis method in the composition of active Ni particles responsible for the growth of CNM is considered to be a key factor providing the stable catalytic performance. The obtained carbon product is represented by well-ordered segmented fibers (0.4–0.8 μm in diameter) and characterized with comparatively high textural parameters (surface area 290–330 m2/g, pore volume 0.43–0.57 cm3/g).

Agglomerates, smoke oxide particles, and carbon inclusions in condensed combustion products of an aluminized GAP-based propellant

In solid propellants, aluminum is widely used to improve the performance, however the condensed combustion products especially the large agglomerates generated from aluminum combustion significantly affect the combustion and internal flow inside the solid rocket motor. To clarify the properties of the condensed combustion products of aluminized propellants, a constant-pressure quench vessel was adopted to collect the combustion products. The morphology and chemical compositions of the collected products, were then studied by using scanning electron microscopy coupled with energy dispersive (SEM-EDS) method. Various structures have been observed in the condensed combustion products. Apart from the typical agglomerates or smoke oxide particles observed before, new structures including the smoke oxide clusters, irregular agglomerates and carbon-inclusions are discovered and investigated. Smoke oxide particles have the highest amount in the products. The highly dispersed oxide particle is spherical with very smooth surface and is on the order of 1–2µm, but due to the high temperature and long residence time, these small particles will aggregate into smoke oxide clusters which are much larger than the initial particles. Three types of spherical agglomerates have been found. As the ambient gas temperature is much higher than the boiling point of Al2O3, the condensation layer inside which the aluminum drop is burning would evaporate quickly, which result in the fact that few “hollow agglomerates” has been found compared to “cap agglomerates” and “solid agglomerates”. Irregular agglomerates usually larger than spherical agglomerates. The formation of irregular agglomerates likely happens by three stages: deformation of spherical aluminum drops; combination of particles with various shape; finally production of irregular agglomerates. EDS results show the ratio of O to Al on the surface of agglomerates is lower in comparison to smoke oxide particles. C and O account for most element compositions for all the carbon inclusions. The rough, spherical, strip shape and flake shape carbon-inclusions are believed to be derived from the degradation products of the binder or oxidizer, while the fiber silk is possibly the combustion product of fiber inside the heat insulation layer of the propellants. Images of products at different pressures reveal high pressure reduces the degree of agglomeration. The chemical compositions, size range and content of all the observed structures are given in this paper. Results of our study are expected to provide better insight in the working process of solid rocket motor.