We present spectral emission characteristics from laser-plasma EUV/SXR sources produced by irradiation of < 1 J energy laser pulse on eleven different double stream gas puff targets, with most intense electronic transitions identified in the spectral range from 1 nm to 70 nm wavelength which corresponds to photon energy from 18 eV to 1240 eV. The spectra were obtained using grazing incidence and transmission spectro- graphs from laser-produced plasma emission, formed by the interaction of a laser beam with a double stream gas puff target. Laser pulses with a duration of 4 ns and energy of 650 mJ were used for the experiment. We present the results obtained from three different spectrometers in the wavelength ranges of SXR (1–5.5 nm), SXR/EUV (4–15.5 nm), and EUV (10–70 nm). In this paper, detailed information about the source, gas targets under investigation, the experimental setup, spectral measurements and the results are presented and discussed. Such data may be useful for the identification of adequate spectral emissions from gasses in the EUV and SXR wavelength ranges dedicated to various experiments (i.e. broadband emission for the X-ray coherence tomography XCT) or may be used for verification of magnetohydrodynamic plasma codes.
Directionally solidified sample of Fe-Fe3C eutectic alloy were produced under an argon atmosphere in a vacuum Bridgman-type furnace to
study the eutectic growth with v = 167 μm/s pulling rate and constant temperature gradient G = 33.5 K/mm. Since how the growth texture
of eutectic cementite is related to its growth morphology remains unclear, the current study aims to examine this relationship. The technique
such as X-ray diffraction, have been used for the crystallographic analysis of carbide particles in white cast irons.
The paper describes the research on soft X-ray lasers with an active medium created using a gas puff target irradiated
with high-intensity laser pulses. The gas puff target in a form of an elongated gas sheet is produced by pulsed injection of
gas through a slit nozzle using a high-pressure electromagnetic valve. The method of generation of soft X-ray lasers using a
laser-irradiated gas puff target has been developed at the Institute of Optoelectronics. The collaborative experiments were
performed at various laser laboratories using high-intensity laser systems to irradiate the gas puff target and pump the X-ray
laser active medium. Results of these experiments are presented and discussed. Works aimed at increasing the efficiency of
X-ray lasers using a longitudinally irradiated gas puff target are also reviewed.
La0,7Ca0,3MnO3 polycrystalline were synthesized from La2O3, CaO and MnO2 powder mixture using a solid state reaction technique. The compound powders were obtained through the free sintering method at different temperatures and sintering times in order to study the influence of technological conditions on Ca doped La manganites. The most important physical features as structure, microstructure and morphology were described after X-ray diffraction investigation. Photographs of the specimen fractures were taken with SEM (scanning electron microscope) and they revealed high porosity of the tested material and great tendency for its grains to create agglomerates. Influence of doping and technological conditions on lattice parameters were studied by means of Rietvield analysis. The XRD measurements reveal that La0,7Ca0,3MnO3 has orthorhombic symmetry with Pnma space group.
The perovskite type matrix is considered as solidification material for high-level radioactive waste. In this work the perovskite-rutile-type matrix doped by Co, Cs, Nd and Sr which simulate nuclear waste was prepared by sol-gel route. The material was characterized by several methods such as: X-ray diffraction, energy dispersive X-ray spectrometer, and particle induced X-ray emission combined with Rutherford backscattering spectrometry. The analyzes confirmed chemical composition Co-Cs-Nd-Sr- doped perovskite-rutile-type structure. A virtual model of the pellet`s structure was created non-destructively by Roentgen computed micro-tomography. The leaching tests confirmed high chemical resistance of the matrix.
In a vacuum Bridgman-type furnace, under an argon atmosphere, directionally solidified sample of Fe - C alloy was produced. The pulling
rate was v = 83 μm/s (300 mm/h) and constant temperature gradient G = 33,5 K/mm. The microstructure of the sample was examined on
the longitudinal section using an Optical Microscope and Scanning Electron Microscope. The X-ray diffraction and electron backscatter
diffraction technique (EBSD) have been used for the crystallographic analysis of carbide particles in carbide eutectic. The
X-ray diffraction was made parallel and perpendicular to the axis of the goniometer. The EBSD shows the existence of iron carbide Fe3C
with orthorhombic and hexagonal structure. Rapid solidification may cause a deformation of the lattice plane which is indicated by
different values of the lattice parameters. Such deformation could also be the result of directional solidification. Not all of the peaks in
X–ray diffractograms were identified. They may come from other iron carbides. These unrecognized peaks may also be a result of the
residual impurity of alloy.
The study of liquid crystalline assemblies, with an emphasis on biological phenomena, is now accessible using newly developed microdevices integrated with X-ray analysis capability. Many biological systems can be described in terms of gradients, mixing, and confinement, all of which can be mimicked with the use of appropriate microfluidic designs. The use of hydrodynamic focusing creates well-defined mixing conditions that vary depending on parameters such as device geometry, and can be quantified with finite element modelling.We describe experiments in which geometry and strain rate induce finite changes in liquid crystalline orientation. We also demonstrate the online supramolecular assembly of lipoplexes. The measurement of lipoplex orientation as a function of flow velocity allows us to record a relaxation process of the lipoplexes, as evidenced by a remarkable 4-fold azimuthal symmetry. All of these processes are accessible due to the intentional integration of design elements in the microdevices.
The technique of electrospinning was employed to fabricate uniform one-dimensional inorganic-organic composite nanofibers at room temperature from a solution containing equal volumes of aluminum 2, 4-pentanedionate in acetone and polyvinylpyrrolidone in ethanol. Upon firing and sintering under carefully pre-selected time-temperature profiles (heating rate, temperature and soak time), high-purity and crystalline alumina nanofibers retaining the original morphological features present in the as-spun composite (cermer) fibers were obtained. Tools such as laser Raman spectroscopy, scanning and transmission electron microscopy together with energy dispersive spectroscopy and selected area electron diffraction were employed to follow
the systematic evolution of the ceramic phase and its morphological features in the as-spun and the fired fibers. X-ray diffraction was used to identify the crystalline fate of the final product.
The article presents an analysis of the change in air voids in asphalt mixtures subjected to fatigue tests at three temperatures of 0°C, 10°C and 25°C. The X-ray computerized tomography imaging method, XCT, was used to identify the air voids in the samples. The research allowed to determine changes in the content of air voids in subsequent fatigue cycles in the sample area. The relationship between air voids volume and the stiffness modulus value was also determined during fatigue for three temperatures. The largest changes were found in samples with notches at 0°C. The analysis of the change in the content of air voids showed that the micro-cracking nucleation processes develop with the number of fatigue cycles. Using the numerical model finite element method we determined the distribution and change in fatigue damage in the extreme areas of the sample during various stages of fatigue. We found clear relationship between the damage and the increased content of air voids.
Casting porosity is the main factor influencing the fatigue properties of Al-Si alloys. Due to the increasing use of aluminum castings, porosity characterization is useful for estimating their fatigue strength. In principle, a combination of metallographic techniques and statistical pore analysis is a suitable approach for predicting the largest defect size that is critical for the casting. Here, the influence of modifiers and casting technology on the largest pore size population in AlSi7Mg alloy specimens is obtained and discussed adopting the Murakami's approach. However, porosity evaluation is a challenge in the case of microshrinkage pores, which are frequently found in industrial castings. Their complicated morphology prevents a reliable definition of an equivalent defect size based on metallographic techniques. This contribution reports the application of X-ray tomography to the 3D reconstruction of real pores in cast Al-Si alloys and provides insight into the complication of microshrinkage pore sizing by metallography.
An attempt was made to determine phase composition of commercial aluminium alloys using X-ray diffraction. Samples for phase composition analysis were selected from the group of aluminium alloys covered by the EN 573-3:2013 standard [1]. Representative samples were taken from eight groups of alloys with different chemical composition (at least one sample from each group). The diffraction intensity was measured with a standard X-ray diffractometer in Bragg-Brentano geometry in a way that allowed identification of the weakest diffraction peaks. As a results of the performed research it has been shown that X-ray phase analysis can be used to identify the matrix of aluminium alloys, Si and crystalline intermetallic phases such as Mg2Si, Al93.38Cu6.02Fe24Si16.27, Al4.01MnSi0.74, MgZn2, Al17(Fe3.2Mn0.8)Si2, Al65Cu20Fe15, and Cu3Mn2Al. The detectability limit of the above-mentioned phases is better than 0.5%. The research has also shown that X-ray phase analysis is applicable in the investigation of phase transformations taking place in aluminium alloys.
Crystal structure and phase composition of stainless steel substrates (AISI 304 type) was studied and it was found that they adopted the cubic symmetry. The calculated elementary cell parameter for the mayor Fe-Ni phase (weight fraction 99%) was a = 3.593 Å, whereas the mean grain size was <D> = 2932 Å. Morphology of the stainless steel substrate surface was studied with profilometry. Mechanical properties of the stainless steel substrates and stainless steel substrates coated with ceramic layer of barium strontium titanate were studied with microhardness tester. For measurements performed according to the Vickers method the average microhardness was found HV = 189 or HV = 186 for the “in-line” and “mapping” measurement pattern, respectively. The sol-gel method was used to coat the surface of the stainless steel substrate with a thin ceramic layer of the chemical composition Ba0.6Sr0.4TiO3. It was found that the stainless steel substrate covered with sol-gel deposited ceramic coating exhibited the average hardness within the range HV = 217 up to HV = 235 for loading force F = 98 mN and F = 0.98 N, respectively. The Knopp method was also used and it was found that the stainless steel substrate with Ba0.6Sr0.4TiO3 coating exhibited hardness HK = 386.
The Ag8SnSe6 argyrodite compound was synthesized by the direct melting of the elementary Ag, Sn and Se high purity grade stoichiometric mixture in a sealed silica ampoule. The prepared polycrystalline material was characterized by the X-ray diffraction (XRD), visible (VIS) and near-infrared (NIR) reflection and photoluminescence (PL) spectroscopy. XRD showed that the Ag8SnSe6 crystallizes in orthorhombic structure, Pmn21 space group with lattice parameters: а = 7.89052(6) Å, b = 7.78976(6) Å, c = 11.02717(8) Å. Photoluminescence spectra of the Ag8SnSe6 polycrystalline wafer show two bands at 1675 nm and 1460 nm. Absorption edge position estimated from optical reflectance spectra is located in the 1413–1540 nm wavelength range.