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Innovative textile materials can be obtained by depositing different coatings. To improve the thermal properties of textiles, aluminum and zirconium (IV) oxides were deposited on the Nomex® fabric, basalt fabric, and cotton fabric with flame-retardant finishing using the magnetron sputtering method. An assessment of coating quality was conducted. Evenly coated fabric ensures that there are no places on the sample surface where the values of thermal parameters such as resistance to contact heat and radiant heat deviate significantly from the specified ones. Energy-dispersive spectroscopy was used for the analysis of modified fabric surfaces. Non-contact digital color imaging system DigiEye was also used. The criterion allowing one to compare surfaces and find which surface is more evenly coated was proposed. The best fabrics from the point of view of coating quality were basalt and cotton fabrics coated with aluminum as well as basalt fabric coated with zirconia. The probability of occurrence of places on the indicated sample surfaces where the values of thermal parameters (i.e., resistance to contact heat and radiant heat) deviated significantly from the specified ones was smaller for Nomex® and cotton fabrics coated with zirconia and Nomex® fabric coated with aluminum.

Herein the deposition and characterization of CuO films with various doping concentrations of boron through the application of the SILAR method are performed. Structural, morphological, and optical properties of the films are determined by SEM with EDS, XRD, and UV/Vis spectroscopy. EDS analysis proved the boron contributions in the films. SEM images showed that boron-doping has a decreasing effect on particle size i.e. the thickness and the length of the nanostructures decreased from 45 to 30 and from 224 to 150 nm, respectively. XRD analyses demonstrated that the crystallite size of the films increased from 12.9 to 15.9 nm with increasing boron concentration which is evidence for increased crystallinity. UV/Vis spectroscopy analysis demonstrated that band gap energy value effectively decreased by boron doping.

Benthic foraminiferal assemblages from 19 superficial marine sediment samples of a coastal area in the Ligurian Sea were analysed for benthic foraminifera in order to recognize changes in assemblage composition and structure, decrease of faunal density, increased morphological abnormalities and inclusion of heavy metals in carbonate tests as possible evidences of environmental stress. Also grain size was determined as a main factor conditioning foraminifer’s distribution. The generalized low faunal density was considered as indicative of environmental stress, attributable to the well-known natural Cr and Ni enrichment, which characterizes marine sediments of the region. The cluster analysis highlighted distinct foraminiferal assemblages with decreasing species diversity approaching to the coast. This distribution was interpreted as the result of local source of environmental stress, probably due to the stream contribution. Deformed foraminifera more abundant than background levels of unstressed environments were also recorded in 39% of samples. Energy Dispersive Spectroscopy (EDS) analyses were carried out on carbonate tests of 55 specimens to investigate the role of the incorporation of heavy metals in the development of morphological abnormalities. Foraminifera showed the inclusion of heavy metals, not present in control specimens, indicating that environmental stress, due to metal sediment enrichment, plays a role in this phenomenon. Although anomalous elements were detected both in normal and deformed specimens and chambers, it was supposed that deformities develop as a result of the toxic effect of heavy metals on cytological activities because, contrarily to the normal specimens, all the deformed ones included anomalous elements. Higher occurrence of deformities in porcelaneous tests, typically enriched in Mg, is associated to the higher number of incorporated elements (Mn, Fe, Cu and Zn).

Electroless low-phosphorus Ni–P coating was deposited on a wrought ZE10 magnesium alloy including an advanced pre-treatment of the material surface before deposition. Uniform Ni–P coating with an average thickness of 10 µm was formed by 95.6 wt % Ni and 4.4 wt % P. The content of Ni and P was homogeneous in the entire cross-section of the coating. Applying the Ni–P coating to the magnesium substrate, the surface microhardness increased from 60 ± 4 HV 0.025 to 690 ± 30 HV 0.025. Using the scratch test, it was determined that deposited Ni–P coating exhibits a high degree of adhesion to the magnesium substrate. Electrochemical corrosion properties of Ni–P coating were analyzed using the polarization tests in 0.1 M NaCl, while the deposited Ni–P coating showed an improvement of the corrosion resistance when compared to the ZE10 magnesium alloy. Using the scanning electron microscopy analysis, it was determined that the fine morphology of the deposited Ni–P coating did not contain visible microcavities. The absence of macrodefects due to the adequate pre-treatment before coating was reflected on the mechanism of the coated ZE10 degradation in a 0.1 M NaCl solution.

The composition of the well-preserved fusion crust of the meteorite Jesenice was characterised by means of optical and scanning electron microscopy (SEM). The SEM investigations revealed three structurally distinct layers within the crust. The features of the first layer on the surface are precipitates, enriched in metal elements (iron, nickel), and the partial melting of silicate grains, which continues deeper into the second layer. The second layer beneath has veins with a heterogeneous composition that indicates a different source of melting minerals. The third layer, which is located deeper within the fusion crust, has not undergone any structural changes and its features are similar to the interior of the meteorite. This is additionally confirmed by the presence of cracks, which are a consequence of shock metamorphism, and irregularly shaped metal and sulphide grains. The structural changes of the thin fusion crust on the surface of this stony meteorite indicate high temperatures (more than 1500 °C) accompanied by high pressures.

With the intention of producing a metal composite consisting of Ag nanoparticles embedded in patterned polystyrene, silver triphenylphosphine nitrate, Ag(PPh3)3NO3, was chosen as a source of Ag metal as it is soluble in toluene to form a blend with polystyrene, a well-known negative tone e-beam resist. At a constant e-beam dosage of 150 ?C cm-2, the patterns were produced at 5, 10, and 30 keV beam energies while varying the dwell time at a location (pixel) and the number of passes. The presence of Ag in the patterned regions was confirmed by the EDS analysis. TEM showed the formation of small Ag nanoparticles in the embedded matrix of the polymer. The reduction of Ag precursor following exposure to the e beam was monitored by XPS. UV-vis absorption studies showed a broad peak at 464 nm, typical of surface plasmon absorption by Ag nanoparticles. Confocal fluorescence studies showed the embedded Ag nanoparticles in the carbon matrix to have fluorescence property as well. C-AFM measurements have shown that the patterned blend is well conducting due to the interacting Ag nanoparticles, the resistance being two orders less compared to that of polystyrene itself. The higher the beam energy, the lower was the dwell time required to attain a conducting pattern. � 2009 American Chemical Society.

International audience; This article presents the results of an experimental study on the Ti17 titanium alloy, which was carried out to analyze tool wear and the degradation mechanisms of an uncoated tungsten carbide tool insert. Two machining conditions, roughing and finishing, have been studied under different lubrication conditions. The experimental procedure included measurement of the cutting forces and the surface roughness. Different techniques have been used to explain the tool wear mechanisms. Distribution maps of the elemental composition of the titanium alloy and the tool inserts have been created using Energy Dispersive X-ray Spectroscopy (EDS). An area of material deposition on the tool rake face, characterized by a high titanium concentration has been observed. The width of this area and the concentration of titanium, decrease when increasing water jet pressure. The study shows that wear mechanisms, with and without high-pressure water jet assistance (HPWJA) are not the same. For example, for the roughing condition using conventional lubrication, the temperature in the cutting area becomes very high, this causes plastic deformation of the cutting edge which results in its rapid collapse. By contrast, this problem disappears when machining with HPWJA. In addition, the evolution of flank wear (VB) is stabilized with high-pressure lubrication. In this case, the most critical degradation mode is due to notch wear (VBn) leading to the sudden rupture of the cutting edge.

The oldest surviving helmet from Estonia is a 13th-century kettlehat found near village of Kodasoo in northern Estonia. Three samples from different parts of the kettlehat were investigated in a metallographic study. The raw material of the Kodasoo kettlehat was a slag-rich iron of heterogeneous carbon content. It was improved by folding and forge-welding it at least three times, resulting in layered structure with more uniformly distributed carbon content.El casco más antiguo encontrado en Estonia es un «chapel de fer» del siglo XIII que proviene de cerca de la aldea de Kodasoo, en el Norte de Estonia. Tres muestras de diversas partes del casco fueron investigadas mediante un estudio metalográfico. El material original del casco de Kodasoo era un hierro de contenido de carbono heterogéneo y con abundantes inclusiones de escoria. Se intentó mejorar su calidad mediante forja, doblándolo y soldándolo a la calda por lo menos tres veces, dando como resultado una estructura estratificada, con el contenido de carbono distribuido más uniformemente.

WOS: 000279650900024, Ottoman mortar is the long-established binding material used for centuries and there are many historical buildings as evidence of its use by Ottomans in Erzurum (Eastern Turkey). The physico-chemical and microscopic properties of the Ottoman mortars in Erzurum have been studied in detail as part of an investigation of the mineral raw materials present in the territory of Turkey. For this purpose, SEM, XRD and EDS analyses of six main types of mortars were carried out showing the presence of organic fibers and calcite, quartz and muscovite minerals. The chemical analyses of the specimens showed that higher SiO(2) + Al(2)O(3) + Fe(2)O(3) contents yielded in higher values of hydraulicity and cementation indices. A significant result of this investigation was that mortars with higher hydraulicity and cementation indices had higher compressive strengths. Most probably this is the main reason why historical Ottoman buildings were resistant against serious earthquakes. (C) 2010 Elsevier Ltd. All rights reserved.