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5Zn0.5Fe2O4 insulating iron powder is promising for reducing core loss and improving the magnetic properties of soft magnetic composites.Boronizing is a thermochemical treatment performed to produce hard and wear-resistant surface layers. In order to control the process and obtain boride layers with the desired properties, it is very important to know how the boronizing parameters and the chemical composition of the treated steel affect the boronizing. The aim of the present study is to investigate the influence of carbon content in carbon steels, boronizing temperature, and boronizing duration on the growth kinetics of boride layers. For this purpose, three carbon steels (C1y5, C45, and C70W2) were boronized in solid medium. The experimental results show that there is a linear relationship between the carbon content and the activation energy values, and between the carbon content and the frequency factors. In addition, a statistical analysis was performed to determine the contribution of each factor. The ANOVA showed that boronizing temperature has the highest effect on the boride layer thickness, followed by the boronizing duration, while the carbon content of the steel has the least effect on the boride layer thickness. Based on a regression model, an empirical equation was derived to estimate the thickness of the boride layer on carbon steels as a function of carbon content, boronizing temperature, and duration.The extensive use of non-degradable microplastics in a wide plethora of daily life products is causing serious pollution problems. More ecofriendly solutions are therefore urgently needed. In this context, the use of lignin, a largely available aromatic polymer, may represent a viable option. Due to the self-assembly ability of its molecules, lignin is in fact an ideal matrix for the fabrication of nanostructures. In this study, lignosulfonate microcapsules containing a limonene core were prepared and characterized in terms of their dimensions and of the physicochemical characteristics of the capsule-forming lignosulfonate molecules. The main purpose is to elucidate the key properties governing the pH-responsive behavior of the capsules to be able to achieve better control over the release kinetics of the entrapped compound(s). The results demonstrate that both the molecular weight and the concentration of sulfonate groups are the most important factors in this respect. Based on these findings, two strategies were followed to further tailor the capsules' behavior (i) fractionation of the starting lignosulfonate by solvent extraction and (ii) introduction of a specific additive in the formulation. The first approach permitted to fabricate highly resistant capsules both in acidic, as well as in alkaline conditions, while in the second case the chemical structure of the additive, the diester diveratryl sebacate, allowed for fast kinetics of release, as values above 70% were reached after 24 h of incubation at pH 4 and pH 12.The band structure and the Fermi surface of the recently discovered superconductor (EMIM)xFeSe are studied within the density functional theory in the generalized gradient approximation. We show that the bands near the Fermi level are formed primarily by Fe-d orbitals. Although there is no direct contribution of EMIM orbitals to the near-Fermi level states, the presence of organic cations leads to a shift of the chemical potential. see more It results in the appearance of small electron pockets in the quasi-two-dimensional Fermi surface of (EMIM)xFeSe.In order to address the problem of sulfur gas and other odors released in the process of using sewage sludge as a construction material, this study prepared multiscale composite particles with a "large scale-medium scale-small scale-micro scale" structure by mixing sludge with silica-alumina building materials. Analysis of the structural changes formed by the internal gas of composite particles due to diffusion at different temperatures and a study of the characteristics of SO2 and H2S release from composite particles were conducted, as well as being compared with the release characteristics of pure sludge, which clarified the mechanism of controlling sulfur-containing-gas release from composite particles. The results showed that compared with pure sludge, the sludge-clay multiscale composite particles were able to reduce the release of SO2 and H2S up to 90% and 91%, and the release temperatures of SO2 and H2S were increased to 120 °C and 80 °C, respectively. Meanwhile, the special structure of the sludge-clay multiscale composite particles and the clay composition are the main factors that hinder the diffusion of sludge pyrolysis gases. Additionally, there are three layers of "gray surface layer-black mixed layer-dark gray spherical core" formed inside the composite particles, which is the apparent manifestation of the diffusion of volatile gases. This study provides theoretical support for the application of multiscale composite particle inhibition of odor-release technology in industrial production.This paper presents the analysis of the behavior of welded joints made of 9-12% Cr-Mo steel SA-387 Gr. 91. The successful application of this steel depends not only on the base metal's (BM) properties but even more on heat-affected-zone (HAZ) and weld metal (WM), both at room and at operating temperature. Impact testing of specimens with a notch in BM, HAZ, and WM was performed on a Charpy instrumented pendulum to enable the separation of the total energy in crack-initiation and crack-propagation energy. Fracture toughness was also determined for all three zones, applying standard procedure at both temperatures. Results are analyzed to obtain a deep insight into steel SA 387 Gr. 91's crack resistance properties at room and operating temperatures. Results are also compared with results obtained previously for A-387 Gr. B to assess the effect of an increased content of Chromium.Nanoscale titanium dioxide (nTiO2 (Hombikat UV 100 WP)) was applied to sewage sludge that was incinerated in a large-scale waste treatment plant. The incineration ash produced was applied to soil as fertilizer at a realistic rate of 5% and investigated in pilot plant simulations regarding its leaching behavior for nTiO2. In parallel, the applied soil material was subject to standard column leaching (DIN 19528) in order to test the suitability of the standard to predict the leaching of nanoscale contaminants from treated soil material. Relative to the reference material (similar composition but without nTiO2 application before incineration) the test material had a total TiO2 concentration, increased by a factor of two or 3.8 g/kg, respectively. In contrast, the TiO2 concentration in the respective leachates of the simulation experiment differed by a factor of around 25 (maximum 91.24 mg), indicating that the added nTiO2 might be significantly mobilisable. Nanoparticle specific analysis of the leachates (spICP-MS) confirmed this finding. In the standard column elution experiment the released amount of TiO2 in the percolates between test and reference material differed by a factor of 4 to 6. This was also confirmed for the nTiO2 concentrations in the percolates. Results demonstrate that the standard column leaching, developed and validated for leaching prediction of dissolved contaminants, might be also capable to indicate increased mobility of nTiO2 in soil materials. However, experiments with further soils are needed to verify those findings.Two Ag(I) complexes with 1,3-bis(imidazol-1-ylmethyl)benzene (bib) and counterions BF4¯ (1) and PF6¯ (2) were synthesized in order to check their behavior in forming molecular/crystal structures. This allows comparison with the final products of analogous syntheses performed with similar bidentate ligands containing methyl substituents on the benzene ring, namely 1,3-bis(imidazol-1-ylmethyl)-5-methylbenzene (bimb) and 1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (bitmb). The Ag(I) complexes obtained with the methylated ligands mentioned above form isostructural pairs of waved 1D chains or dinuclear boxes, of general formula [Ag(bimb)]Xn and [Ag2(btmb)2]X2, respectively (X = BF4¯, PF6¯), under the same reaction conditions. SCXRD analyses of 1 and 2 revealed the formation of polymeric coordination compounds of formula [Ag2(bib)3](BF4)2n and [Ag(bib)]PF6n, respectively, different from those observed for bimb. The 3D coordination polymer 1 forms a unique 5,5-c net of 5,5T188 topological type, observed for the very first time for a coordination compound, with silver cations adopting a trigonal geometry, whereas 2 shows the presence of 1D single-stranded cationic helices with linear coordination of the metal centers. Interestingly, these complexes differ not only from the mentioned isostructural pairs of related Ag(I) complexes, but also from the isostructural pair of compounds obtained as the final product when reacting bib and bimb with the larger counterion CF3SO3¯. Hirshfeld surface analyses indicate a higher contribution of F···H intermolecular contacts in 2 than in 1, with H…H contacts being dominant in the latter.To investigate atomic oxygen effects on tribological properties of Mo/MoS2-Pb-PbS film and further enlarge application range, atomic oxygen exposure tests were carried out for 5 h, 10 h, 15 h, and 20 h by the atomic oxygen simulator with atomic oxygen flux of 2.5 × 1015 atoms/cm2·s. The exposure time in test was equivalent to the atomic oxygen cumulative flux for 159.25 h, 318.5 h, 477.75 h, and 637 h at the height of 400 km in space. Then, the vacuum friction test of Mo/MoS2-Pb-PbS thin film was performed under the 6 N load and 100 r/min. By SEM, TEM, and XPS analysis of the surface of the film after atomic oxygen erosion, it was observed that atomic oxygen could cause serious oxidation on the surface of Mo/MoS2-Pb-PbS film, and the contents of MoS2, PbS, and Pb, which were lubricating components, were significantly reduced, and oxides were generated. From AES analysis and the variation in the main element content, Mo/MoS2-Pb-PbS thin film showed self-protection ability in an atomic oxygen environment. Hard oxide generated after atomic oxygen erosion such as MoO3 and Pb3O4 could cause the friction coefficient slight fluctuations, but the average friction coefficient was in a stable state.KMeY(PO4)25% Eu3+ phosphates have been synthesized by a novel hydrothermal method. Spectroscopic, structural, and morphological properties of the obtained samples were investigated by X-ray, TEM, Raman, infrared, absorption, and luminescence studies. The microscopic analysis of the obtained samples showed that the mean diameter of synthesized crystals was about 15 nm. The KCaY(PO4)2 and KSrY(PO4)2 compounds were isostructural and they crystallized in a rhabdophane-type hexagonal structure with the unit-cell parameters a = b ≈ 6.90 Å, c ≈ 6.34 Å, and a = b ≈ 7.00 Å, c ≈ 6.42 Å for the Ca and Sr compound, respectively. Spectroscopic investigations showed intense 5D0 → 7F4 transitions connected with D2 site symmetry of Eu3+ ions. Furthermore, for the sample annealed at 500 °C, europium ions were located in two optical sites, on the surface of grains and in the bulk. Thermal treatment of powders at high temperature provided better grain crystallinity and only one position of dopant in the crystalline structure. The most intense emission was possessed by the KSrY(PO4)25% Eu3+ sample calcinated at 500 °C.

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