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Featured Application: Authors are encouraged to provide a concise description of the specific application or a potential application of the work. This section is not mandatory. In this study, a new procedure for mounting tissue blocks was described while cutting and grinding the section remains tightly bound to the inert glass surface both chemically and micro mechanically allowing good quality specimens for staining and microscopic analysis. The micromechanical interlocking was achieved by using of frosted glass, the chemical binding was made with 10-methacryloyloxydecyl dihydrogen phosphate monomer (10-MDP) containing bond material. The glass surface activation was achieved by nitric acid etching and the surface was characterized by zeta potential, X-ray photoelectron spectroscopy (XPS), and contact angle measurements. Cylindrical samples were prepared from epoxy embedding materials, cortical bovine bone, and dental titanium to investigate the shear bond strengths (SBS) to microscopic glass slide compared to a routinely used thermoplastic adhesive. Based on the experiments it was found that the micromechanical retention combined with MDP containing bond material improved the SBS data compared to the thermoplastic adhesive. The acid etched glass became positively charged that significantly increased the SBS data of bone and titanium compared with the uncharged version. Therefore, the thickness of the undecalcified bone section with metal can safely reduce to improve histological microscopic analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Simplified preparation of thiol functionalized short range ordered mesoporous silicas. • Selective sorption of aqueous Ag(I) with a capacity of 238 mg g−1 at pH = 5.0. • Sorption equilibrium establishes extremely fast, in 15 min contact time. • Strong and selective binding of Ag(I) due to the formation of layered thiolate coordination compounds on the surface. • Quantitative recovery of Ag(I) and sorbent regeneration with 10 mM Na 2 S 2 O 3 solution. A simplified sol–gel method was developed for the preparation of thiol functionalized porous silica particles using (3-mercaptopropyl)-trimethoxy-silane (MPTMS) for co-gelation in the presence of micellar templates. The resulting short range ordered porous silica microparticles are exceptionally effective sorbents of aqueous Ag(I). The binding of aqueous Ag(I) is almost stoichiometric in the broad pH range between 4.0 and 9.0 even at low Ag(I) concentrations until reaching the limiting 238 mg g−1 sorption capacity. The sorbent displays high selectivity towards Ag(I), which was tested in the simultaneous presence of several different metal compounds. The practically complete recovery of Ag(I) and the regeneration of the sorbent was achieved by washing with a 10 mM Na 2 S 2 O 3 solution. X-ray photoelectron spectroscopy (XPS) revealed that silver is not reduced on the surface of the sorbent. The reason for the strong and selective binding of Ag(I) is the formation of layered thiolate coordination compounds on the functionalized silica surface that display characteristically high stability even in the presence of other competing metal ions. [ABSTRACT FROM AUTHOR]

Tin (Sn) -bentonite was prepared by ion exchange method from Ca-bentonite. For the ion exchange process, tin-chloride (SnCl 2) solution was prepared from metallic tin, and the tin concentration was determined by Microwave Plasma Atomic Emission Spectroscopy (MP-AES). Sn-bentonite was characterized by X-ray fluorescence spectrometry (XRF), X-ray powder diffraction (XRPD), X-ray photoelectron spectroscopy (XPS) and 119Sn as well as iron-57 (57Fe) Mössbauer spectroscopy. 119Sn Mössbauer spectroscopy and XPS undoubtedly revealed both Sn+2 and Sn+4 ions in Sn-bentonite. SnII was attributed to be incorporated into the interlayer space while SnIV located partly in the octahedral position and in the interlayer space of montmorillonite. The removal of radioactive pertechnetate anion (99mTcO 4 -) was studied on Sn-bentonite in aqueous and artificial urine media. Based on the measurement results, 99mTcO 4 - ion can be removed, in case of aqueous media, the equilibrium is reached after 5 mins (x = 99.9 ± 0.01%, k = 4.2 ± 0.83 1/min) (Buzetzky et al., 2019), while in the case of urine media the equilibrium is reached after 30 mins (x = 59.1% ± 2.7, k = 0.18 ± 0.05 1/min). Pertechnetate anoin sorption on tin-bentonite is a (Sn(II/IV)-TcO 4 -) redox reaction. Thus, Sn-bentonite can be a suitable sorbent for radioactive waste management. [Display omitted] [ABSTRACT FROM AUTHOR]

Grain boundary (GB) diffusion of Si in polycrystalline Cu film was studied in the temperature range of 403–453 K, in the C-type kinetic regime. The amorphous Si layer (80 nm) and polycrystalline Cu layer (40 nm) were successively deposited by magnetron sputtering at room temperature onto a Si (111) wafer. Appearance of Si atoms on the copper surface due to GB diffusion through the copper layer was detected by low energy ion scattering spectroscopy with high sensitivity. The depth distribution of Si in Cu grain boundaries was revealed by secondary neutral mass spectrometry. Surface morphology of Cu films was investigated by scanning tunneling microscopy. Identification of Si chemical bonds on the surface layer was made by X-ray photoelectron spectroscopy. GB diffusion coefficients were estimated by the relation used for calculation of diffusant distribution from a constant source in assumption that the diffusion path equals to the film thickness at the moment of appearing Si atoms on the Cu surface. At 453 K we estimated the surface segregation factor and detected formation of Cu–O–Si atomic bonds on the Cu film surface. • Nanoscale grain boundary diffusion of silicon. • Nanoscale depth profile analysis. • Application of low energy ion scattering for study of nanoscale diffusion mechanisms. [ABSTRACT FROM AUTHOR]

The mechanism of active screen plasma nitriding (ASPN) and the influence of the active screen's coating material on the surface properties of the nitrided layer was investigated on low alloyed steel samples, using chromium or nickel-coated active screens. ASPN experiments were performed at 510 °C, for 5 h in a 75% N 2 + 25% H 2 gas mixture using tempered 42CrMo4 type low alloy steel. The base material of the screens was unalloyed steel, but the screens were electroplated with chromium or nickel. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffractometry (XRD), atomic force microscopy (AFM), and secondary neutral mass spectrometry (SNMS) were used for the characterization of surface properties of the samples and the screen. SNMS results show that the coating material of the active screen (chromium or nickel) was deposited on the surface of the samples in the form of compounds, with layer thicknesses between 160 and 200 nm (chromium) and 290–420 nm (nickel). Chemical analysis by X-ray photoelectron spectroscopy (XPS), performed at the interface of the steel sample and the deposited compounds reveals that iron-nitride was only formed in the case of samples that were treated with a Cr-coated active screen. Here the decomposition and oxidation of the unstable chromium-nitride provided the nitrogen atoms and the chemical drive for the formation of iron-nitride. In the case of the Ni-coated active screen, only molecular nitrogen was observed in the treated steel samples. The results prove that – contrary to widespread models on ASPN nitriding mechanisms – physically adsorbed nitrogen plays little role in the nitriding process of iron. • The material of the active screen is a major parameter which influences the outcome of the nitriding. • Cr- and Ni-coated active screen plasma nitriding produced uniform layer. • Cr- and Ni-nitrides are sputtered and subsequently deposited on the surface from the screen. • The effect of physically adsorbed and desorbed N is much lower since iron-nitride cannot be found. [ABSTRACT FROM AUTHOR]