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A series of TiN/ITO composite films with various thickness of ITO buffer layer were fabricated in this study. The enhancement of optical properties was realized in the composite thin films. The absorption spectra showed that absorption intensity in the near-infrared region was obviously enhanced with the increase of ITO thickness due to the coupling of surface plasma between TiN and ITO. The epsilon-near-zero wavelength of this composite can be tuned from 935 nm to 1895 nm by varying the thickness of ITO thin films. The nonlinear optical property investigated by Z-scan technique showed that the nonlinear absorption coefficient (β = 3.03 × 10−4 cm/W) for the composite was about 14.02 times greater than that of single-layer TiN films. The theoretical calculations performed by finite difference time domain were in good agreement with those of the experiments.

In this paper, V2O5 thin-films were deposited on glass substrates by using the ultrasonically nebulized spray pyrolysis technique. Doping concentration of 1 %, 2 %, and 7 % of Sn, in V2O5 thin-films is studied by using metal–semiconductor-metal (MSM) based device structure. X-ray diffractometer (XRD) and field emission scanning electron microscope (FESEM) were used to analyze the surface morphology of the thin films. The XRD spectroscopic analysis shows the crystal size of above-mentioned samples, to be respectively 39 nm, 58 nm, 60 nm and 72 nm. The FESEM images showed the enhancement of crystal size with increase in Sn doping concentration. The optical properties of Sn doping on V2O5 thin film were studied by using UV–Vis spectrometer. The UV–Vis spectroscopic analysis shows that the absorption coefficient values decrease with increase in concentration of Sn metal doping in V2O5 thin film. The activation energies of all thin-film samples were calculated from Arrhenius plots and were found to be 0.938 eV, 1.101 eV, 1.11 eV and 1.169 eV, respectively, for all the thin-film samples mentioned above. The MSM based structure was fabricated by using a shadow mask and thermal evaporation. Later, the I-V characteristics of all the thin films were obtained by using semiconductor parameter analyzed at a biased voltage between −50 V and + 50 V with a step size of 1 V. Rectification ratio of the V2O5 films is significantly enhanced as the doping concentration increases. It was found that the rectification ratio of undoped V2O5 thin films increased linearly from 1.018 to 1.059 with an increase in temperature from room temperature to 130 °C. Similar trend was followed for 1 % (from 1.079 to 1.198), 2 % (from 1.081 to 1.224) and 7 % (from 1.095 to 1.311) Sn doped films. These results show the potential application of V2O5 thin films in the field of optoelectronics and thin film gas sensors.

This work focuses on the synthesis of titanium nitride–carbon (TiN–carbon) composites by the thermal decomposition of a titanyl phthalocyanine (TiN(TD)) precursor into TiN. The synthesis of TiN was also performed using the sol-gel method (TiN(SG)) of an alkoxide/urea. The structure and morphology of the TiN–carbon and its precursors were characterized by XRD, FTIR, SEM, TEM, EDS, and XPS. The FTIR results confirmed the presence of the titanium phthalocyanine (TiOPC) complex, while the XRD data corroborated the decomposition of TiOPC into TiN. The resultant TiN exhibited a cubic structure with the FM3-M lattice, aligning with the crystal system of the synthesized TiN via the alkoxide route. The XPS results indicated that the particles synthesized from the thermal decomposition of TiOPC resulted in the formation of TiN–carbon composites. The TiN particles were present as clusters of small spherical particles within the carbon matrix, displaying a porous sponge-like morphology. The proposed thermal decomposition method resulted in the formation of metal nitride composites with high carbon content, which were used as anodes for Li-ion half cells. The TiN–carbon composite anode showed a good specific capacity after 100 cycles at a current density of 100 mAg−1.

Abstract In this study, we used a specially designed aluminum anodic oxide (AAO) template technique to produce interconnected self‐standing tin nanowire electrocatalysts having a high surface‐to‐volume ratio for CO2 reduction toward formate. These electrodes consisted of interconnected tin nanowires with 150 nm diameter and 7 μm length supported on 70–100 μm thick tin film. As prepared electrodes produced 6 times higher formate than the flat tin sheets, yet Faradaic efficiencies (FE%) were unsatisfactory. The main reason for low FE% is determined as the etching of native oxide on tin nanowires during hot alkali treatment to remove AAO and remnant aluminum. Porous anodic oxidation in 1 M NaOH solution was realized to recover tin oxides on the surface. Anodized tin nanowire electrocatalysts produced higher formate than anodized tin sheets, reaching FEformate% of ~87 at −1 V vs. RHE cathodic reduction potential. Moreover, while anodic oxide on flat tin flaked off the surface in 1 h, these electrodes preserved their integrity and formate production ability even after 12 h.

Tribological properties of tin (Sn)-zinc (Zn) hybrid coating on bronze were evaluated in lubricated condition mating with a chromium alloy steel (Japanese Industrial Standards, JIS SUJ2) flat surface. A shot peening technique using Sn and Zn fine powders as the impact media was applied to the coating process. The resulted coating film thickness was approximately 1-2 µm. Tribological properties of mono-layered coating showed that the friction coefficient and the wear loss were considerably smaller than those of the bronze and that the transfer layer morphology was different depending on the coating material. Further decrease of the friction coefficient was found on the hybrid Sn-Zn coating surface and Zn transfer layer accompanying with oxygen reduced. Therefore, it is concluded that hybrid Sn-Zn coating is effective means to improve the tribological properties of bronze surface.

Social distancing measures due to the SARS-CoV-2 virus have profoundly challenged the educational experimental work. We have sought to remediate this issue by designing a series of low cost, low risk, quick, and qualitative electrochemistry and corrosion experiments to be performed in the student’s homes at the microscale with a kit provided by the teacher. One such experience is the electroplating of Sn from an aqueous chloride solution using readily available soldering wires (e.g., Sn–Pb alloy, or Sn–Ag–Cu alloy). This process catches students’ attention due to its simplicity and variety of possible applications that include corrosion protection, fabrication of electronic components, plating of cooking utensils, lithium batteries, etc.

Rechargeable aqueous zinc-iodine batteries have received extensive attention due to their inherent advantages such as low cost, flame retardancy and safety. To address the safety concern associated with Zn dendrites, tin functional layer is introduced to the Zn surface via a spontaneous galvanic replacement reaction. This provides rapid deposition kinetics, thereby achieving the uniform Zn plating/stripping with a low overpotential (13.9 mV) and good stability for over 900 h. Importantly, the coupling of the advanced Zn anode with iodine in Zn-I2 battery exhibits a high specific capacity of 196.4 mAh·g−1 with high capacity retention (90.7%). This work provides a reliable strategy to regulate the reversible redox of zinc for advanced rechargeable batteries.

For a very long period, tin was considered one of the most important metals for humans due to its easy access in nature and abundance of sources. In the past, tin was mainly used to make various utensils and weapons. Today, nanostructured tin and especially its oxide materials have been found to possess many characteristic physical and chemical properties that allow their use as functional materials in various fields such as energy storage, photocatalytic process, gas sensors, and solar cells. This review discusses current methods for the synthesis of Sn/SnO2 composite materials in form of powder or thin film, as well as the application of the most advanced characterization tools based on large-scale synchrotron radiation facilities to study their chemical composition and electronic features. In addition, the applications of Sn/SnO2 composites in various fields are presented in detail.

Aiming at developing low-cost, high-performance catalysts for the electrochemical reduction of CO2 (CO2-ERR) to valuable multicarbon (C2–C3) chemicals to alleviate global warming, trimetallic alloy electrocatalysts containing Cu, Ni, and Sn supported on a Pd-activated carbon fabric substrate (CS) were prepared via an electroless deposition method. The as-deposited CuNiSn/CS electrocatalysts were employed in CO2-ERR in an H-cell type reactor at an applied potential of −1.6 V vs. Ag/AgCl. The effect of the electroless deposition time (15, 30, and 45 min) was investigated, finding no significant structural differences according to the X-ray diffraction patterns. The evaluation of the reaction performance via linear sweep voltammetry revealed that CO2 was more effectively reduced to adsorbed species on the catalytic surface sites of the electrocatalyst prepared with a 30 min deposition time. The analysis of the gas and liquid products via gas chromatography and nuclear magnetic resonance, respectively, revealed that the Faradaic efficiency and H2 production over CuNiSn/CS was lower than those over related bimetallic and monometallic electrocatalysts, indicating the inhibition of the competitive H2 evolution reaction. Liquid products including formate, ethylene glycol, acetone, ethanol, acetate, and 1-buthanol were detected.

Abstract TiN and ZnSiN2 nanoparticles are obtained via a novel pyridine‐based synthesis route. This one‐pot liquid‐phase route strictly avoids all oxygen sources (including starting materials, surface functionalization, solvents), which is highly relevant in regard of the material purity and material properties. Colloidally stable suspensions of crystalline, small‐sized TiN (5.4±0.4 nm) and ZnSiN2 (5.2±1.1 nm) are instantaneously available from the liquid phase. Elemental analysis and electron energy loss spectroscopy confirm the purity of the compounds and specifically the absence of oxygen. The as‐prepared ZnSiN2 show yellowish emission (500‐700 nm) already at room temperature with its maximum at 570 nm.

Structural investigations of molecular crystal solvates can provide important information for the targeted crystallization of particular inclusion compounds. Here, the crystal structure of the first ether solvate of hexaphenyldistannane [(Ph3Sn)2 • 2 THF] is reported. Structural features in terms of host-guest interactions and in the context of the previously reported polymorphs and solvates of (Ph3Sn)2 are discussed.

This paper presents a deepening on the investigation of the Rh-Sn system of heterometallic carbonyl clusters. More specifically, we herein report the synthesis and isolation of the new [Rh7Sn4Cl10(CO)14]5− (1) compound and the atomically precise [Rh18Sn3Cl2(CO)33]4− (2) nanocluster. Cluster 1 can be obtained by reacting the [Rh7(CO)16]3− homometallic cluster with hydrated Sn(II) chloride, in acetone; conversely, cluster 2 derives from the previously known [Rh12Sn(CO)23Cl2]4− precursor after controlled addition of diluted sulphuric acid. Notably, only 2 has retained the recurrent Sn-centred icosahedral structural feature, while 1 shows a molecular structure based on two Rh4 tetrahedra joint by one vertex and stabilized by SnCl2 and [SnCl3]− fragments. Both species have been characterized by infrared (IR) analysis in solution, single-crystal X-ray diffraction and Electrospray Ionization Mass Spectrometry (ESI-MS).

Pure and mixed oxides were synthesized using three methods, namely, coprecipitation, hydrothermal treatment using CTAB and Pechini treatment using glycerol, and investigated for the transformation of fructose, aiming to determine the influence of textural, structural, and acid-base properties on conversion and selectivity. All systems led to fructose conversion in an aqueous medium, and the factors that influenced the transformation were the textural and structural properties, as well as the number of acid sites present in the catalysts. The best conversions were observed using mixed oxides, highlighting SnNb (CTAB) and SnNb (GLY), showing the importance of the modulation of properties using the synthesis method. All systems were selective mainly for 5-HMF (5-hydroxymethylfurfural) and, to a lesser extent, for the products of the retro-aldolic route, and this selectivity was preserved, regardless of the catalytic system used.

Platinum–tin-containing materials are the most popular catalysts for processes occurring in fuel cells with direct ethanol oxidation. Pulse electrolysis based on the electrochemical dispersion of platinum electrodes under the influence of alternating pulse current in an alkaline electrolyte made it possible to introduce the tin component into the catalyst in the form of a dopant, an alloy with platinum, and in the form of an oxide phase and evaluate the effect of the form in which tin is present in the catalyst on its microstructural and electrocatalytic characteristics. The introduction of tin into the catalyst generally increases the rate of ethanol electrooxidation; however, with the most prominent effect observed when tin is present in form of an oxide.

Stable ethylene glycol (EG) and propylene glycol (PG) electrolytes containing СuCl2 · 2H2O, SnCl4 · 5H2O and Trilon B have been developed, which provide electrodeposition of Cu – Sn alloy with tin content varying from 34 to 52 at. % in case of EG and from 51 to 91 at. % in case of PG electrolytes. It is found that the coatings contain phases of Cu6Sn5 и Cu10Sn3 intermetallic compounds, and metallic tin is also present in case of its highest content in the alloy. It is revealed that tin content can be simply varied by the change of current density or concentrations of tin and copper compounds in glycols. The effect of electrolyte composition, deposition conditions, a nature of a substrate on the coatings deposition rate (in the limits of 0.9‒2.9 μm ∙ h‒1), total metal current efficiency (from 40 to 95 %), the ratio of metals in the alloy (from 34 to 91 at. %), its phase composition and microstructure is determined. The conditions for the deposition of Cu – Sn alloy close to the eutectic composition have been found.

The optimal conditions for the electrochemical synthesis in the sulfate electrolyte of low-melting Sn–Ag alloy coatings used in the assembly of electronic equipment containing 7.1–8.3 at. % of silver and with total current yield of metals equal to 88.8–87.0 % are determined. It is established that electrochemical reduction of Sn(II) and Ag(I) on the surface of the alloy is accompanied by the process of contact displacement of Ag(I) with tin included into the coating. The process of contact displacement is intensified with the electrolyte temperature growth and leads to the increase in silver content in the alloy, to the appearance of dendrites on the surface of the coating due to its passivation.

This paper compares velocities of tin and copper etching in solution of different compositions. We identified optimal concentration of based components – nitric acid (4.5 mol / L) and Fe(III) ions (0.18 mol / L). To avoid solution’s worm up and toxic nitric oxides allotment during etching, we propose to add to solution stabilizator-inhibitor based on sulfur- and amino-containing derivatives compounds in concentration 0.015 mol / L. Further addition of benzotriazole and chloride ions results in bright and shiny copper etched surface. Tin and copper ions presence in solution accelerates dissolution’s processes of both metals. Polarization data illustrates that anodic copper dissolution is noticeably lower during etching in the presence of both benzotriazole and stabilizator-inhibitor currents. Finally, the analysis of electron microscopic data shows that copper surface after etching is sufficiently smooth and slightly structured with these solution additives. In contrast, etching in other solutions leads to more developed and structured surfaces.

Traditional view holds that transition metal nitride films have high friction coefficient and difficult to regulate. It is very challenging to obtain low friction consumption, which limits their wide application. Here, the tribological behavior of TiN films prepared by multi-arc ion plating and GCr15 steel balls under nitrogen atmosphere have been systematically investigated. It is interesting that TiN film in an alternating atmosphere shows a good adaptability similar to that of H-DLC films in the atmosphere of nitrogen. Specifically, the friction coefficient is higher in vacuum, but lower in nitrogen atmosphere. The multi-cycle variation in the frictional environment confirms the adsorption of nitrogen molecules at the sliding interface. The X-ray photoelectron spectroscopy results from the wear tracks show the formation of oxide and the adsorption of nitrogen at the sliding interface. In addition, the synergistic mechanism of N 2 molecule as electron donor and electrostatic repulsion and nitrogen atoms and tribo-transfer film was established. It provides a general strategy for the regulation of hard films in nitrogen atmosphere. Image 1 • The controllable friction coefficient of TiN films under alternating atmosphere is reported. • The first time to explain the friction mechanism in nitrogen by using oxide ion potential and electrostatic repulsion. • TiN films have broad application prospects in nitrogen atmospheres. [ABSTRACT FROM AUTHOR]

Tin and tin compounds are perceived as promising next-generation lithium (sodium)-ion batteries anodes because of their high theoretical capacity, low cost and proper working potentials. However, their practical applications are severely hampered by huge volume changes during Li+ (Na+) insertion and extraction processes, which could lead to a vast irreversible capacity loss and short cycle life. The significance of morphology design and synergic effects-through combining compatible compounds and/or metals together-on electrochemical properties are analyzed to circumvent these problems. In this review, recent progress and understanding of tin and tin compounds used in lithium (sodium)-ion batteries have been summarized and related approaches to optimize electrochemical performance are also pointed out. Superiorities and intrinsic flaws of the above-mentioned materials that can affect electrochemical performance are discussed, aiming to provide a comprehensive understanding of tin and tin compounds in lithium(sodium)-ion batteries.

The Ti/SnO2 interface has been investigated in situ via the technique of x-ray photoelectron spectroscopy. Thin films (in the range from 0.3 to 1.1 nm) of titanium were deposited on SnO2 substrates via the e-beam technique. The deposition was carried out at two different substrate temperatures, namely room temperature and 200 °C. The photoelectron spectra of tin and titanium in the samples were found to exhibit significant differences upon comparison with the corresponding elemental and the oxide spectra. These changes result from chemical interaction between SnO2 and the titanium overlayer at the interface. The SnO2 was observed to be reduced to elemental tin while the titanium overlayer was observed to become oxidized. Complete reduction of SnO2 to elemental tin did not occur even for the lowest thickness of the titanium overlayer. The interfaces in both the types of the samples were observed to consist of elemental Sn, SnO2, elemental titanium, TiO2, and Ti-suboxide. The relative percentages of the constituents at the interface have been estimated by curve fitting the spectral data with the corresponding elemental and the oxide spectra. In the 200 °C samples, thermal diffusion of the titanium overlayer was observed. This resulted in the complete oxidation of the titanium overlayer to TiO2 upto a thickness of 0.9 nm of the overlayer. Elemental titanium resulting from the unreacted overlayer was observed to be more in the room temperature samples. The room temperature samples showed variation around 20% for the Ti-suboxide while an increasing trend was observed in the 200 °C samples.

Abstract Flow field-flow fractionation (Fl-FFF) for silica nanoparticles with offline inductively coupled plasma mass spectrometry (ICP-MS) was applied to investigate the adsorption behavior of tin onto silica nanoparticles. Effect of carrier solutions and membranes was studied to achieve better separation for silica nanoparticles prior to tin detection using ICP-MS. Investigation was carried out by using 0.25 mM ammonium carbonate and 0.02% FL-70 with 0.02% NaN3 as carrier solutions with 1 kDa regenerated cellulose (RC), 10 kDa regenerated cellulose (RC), and 10 kDa polyethersulfone (PES) membranes. Ammonium carbonate carrier solution with suitable ionic strength provided good separation with minimization of particle-membrane interaction. Better retention was shown by employing 10 kDa RC membrane. Furthermore, Fl-FFF was employed for the separation of silica nanoparticles incubated with tin. Fractions eluted from Fl-FFF were collected and then introduced into ICP-MS. Tin was adsorbed onto silica nanoparticles with different adsorption capabilities depending on particle size. Adsorption of tin was greater on the smaller size of silica nanoparticles compared to the bigger size with the adsorption percentage of 98.5, 44.9, and 6.5 for 60 nm, 100 nm, and 200 nm, respectively. Size-dependent adsorption of tin was in good agreement with surface area per volume of silica nanoparticles.

Pierre Bayen (1725-1798), a French pharmacist, made significant contributions to chemistry, metallurgy, and geology. Among the many position he occupied, the most important was being head of the pharmaceutical services of the army, His work about mineral waters, led him to discover the fulminant effect of mixtures of sulfur with mercury oxides, that the red oxide of mercury was self-reducing, that during its reduction an elastic fluid separate (oxygen, which he did not identify), and that during the oxidation of metals, they absorbed an elastic fluid from the atmosphere. These results led him to be the first European scientist to openly reject the phlogiston theory (all this, years before Lavoisier). Together with Venel they disproved the claim that tin contained poisonous amounts of arsenic.

The additions of hydroquinone, 1,4-butandiol and citrate ions to the known strongly acidic sulfate-thiourea solution for electrochemical deposition of Sn – Ag low-melting alloy are proposed, which provide to obtain the alloys of composition near to the eutectic one. It is shown that varying the content of the additions and current density it is possible to control tin content in the alloy in the range of 73–96 wt. %, the rate of coatings deposition from 2.7 to 15.6 µm/h, the total current yield in the range of 55–99 %. It is determined that coatings consist of fine silver grains less than 0.5 µm in size and lamellar tin crystals 3–20 µm in size, increasing with the rise of tin fraction in the alloy. According to thermal analysis data the maximum of endothermic peak in DSC curves corresponding to the melting of Sn – Ag alloy with tin content over 73 wt. % is found at 223.5 °С, that is close to the melting temperature of the eutectic. The area of this peak increases with tin quota in the alloy. Sn – Ag coatings containing more than 93 wt. % of tin, similar in composition to the eutectic are characterized by high spreading of the molten solder even better as compared with tin, which makes these coatings promising for soldering.

This review article collects and discusses the syntheses of the currently known metal‐free heavier tetrylenes having a PEP pincer topology (E = tetrel atom) as well as their transition metal derivative chemistry. To date, only five PGeP germylenes and two PSnP stannylenes have been isolated. These compounds have been successfully synthesized by treating GeCl2(diox) (diox = 1,4‐dioxane), GeCl2(NHC) (NHC = N‐heterocyclic carbene) or SnCl2 with two equivalents of an appropriate lithiated phosphine. Their transition metal chemistry is dominated by processes in which, in addition to the coordination of one or both phosphane groups, the E atom ends inserted into M–M or M–X (X = anionic group) bonds. Only in a few occasions a simple coordination of the tetrylene fragment (as a neutral two‐electron‐donor ligand) has been observed. The structural and bonding characteristics of the metal‐free PEP tetrylenes and of relevant examples of their transition metal derivatives are also surveyed. [ABSTRACT FROM AUTHOR]

Tin(IV) tricycles form a class of structurally unique and topologically attractive molecules with challenging synthetic attributes. Particularly, "stannatranes and pseudostannatranes" are among the most intensively studied representatives of tin(IV) tricycles. In light of recent research perspectives, this review discusses the progress of stannatranes and pseudostannatranes over the past decades. Herein, stannatranes and pseudostannatranes are arranged into various groups based on their cage skeletons. The synthetic aspects of stannatranes are summarized for different categories of ligating systems, viz. stannatranes with nitrilotriethanolate cages, aminotricarboxylate cages, and substituted nitrilotriethanolate cages. Likewise, detailed synthetic discussions of pseudostannatranes are presented in subsequent sections, comprising [3.3.3.01,5], [4.3.3.01,5], [4.4.3.01,5] and [4.4.4.01,6] cages. Further, intriguing features of stannatranes and pseudostannatranes, such as variation in the Sn–N transannular bond, oligomerization, extended exocyclic bonds, aqueous chemistry and unique spectroscopic aspects, are explained with appropriate examples. Stannatranes possess interesting structural topologies and physical features which can be tuned by controlling the rigidity/flexibility of the ligating system. The choice of the rigid skeleton mitigates oligomerization effects and allows access to highly stable monomeric frameworks. The stability of these systems in aqueous systems facilitates the formation of new hydrolytic species and allows chemical reactivity of the exocyclic bond to obtain new stannatranes. [ABSTRACT FROM AUTHOR]

Carbon nano-onions (CNOs) were successfully synthesized by employing the flame pyrolysis (FP) method, using flaxseed oil as a carbon source. The alcohol reduction method was used to prepare Pd/CNOs and Pd-Sn/CNOs electro-catalysts, with ethylene glycol as the solvent and reduction agent. The metal-nanoparticles were supported on the CNO surface without adjusting the pH of the solution. High-resolution transmission electron microscopy (HRTEM) images reveal CNOs with concentric graphite ring morphology, and also PdSn nanoparticles supported on the CNOs. X-ray diffractometry (XRD) patterns confirm that CNOs are amorphous and show the characteristic diffraction peaks of Pd. There is a shifting of Pd diffraction peaks to lower angles upon the addition of Sn compared to Pd/CNOs. X-ray photoelectron spectroscopy (XPS) results also confirm the doping of Pd with Sn to form a PdSn alloy. Fourier transform infrared spectroscopy (FTIR) displays oxygen, hydroxyl, carboxyl, and carbonyl, which facilitates the dispersion of Pd and Sn nanoparticles. Raman spectrum displays two prominent peaks of carbonaceous materials which correspond to the D and G bands. The Pd-Sn/CNOs electro-catalyst demonstrates improved electro-oxidation of methanol and ethanol performance compared to Pd/CNOs and commercial Pd/C electro-catalysts under alkaline conditions.

Coupling of cells to biomaterials is a prerequisite for most biomedical applications; e.g., neuroelectrodes can only stimulate brain tissue in vivo if the electric signal is transferred to neurons attached to the electrodes’ surface. Besides, cell survival in vitro also depends on the interaction of cells with the underlying substrate materials; in vitro assays such as multielectrode arrays determine cellular behavior by electrical coupling to the adherent cells. In our study, we investigated the interaction of neurons and glial cells with different electrode materials such as TiN and nanocolumnar TiN surfaces in contrast to gold and ITO substrates. Employing single-cell force spectroscopy, we quantified short-term interaction forces between neuron-like cells (SH-SY5Y cells) and glial cells (U-87 MG cells) for the different materials and contact times. Additionally, results were compared to the spreading dynamics of cells for different culture times as a function of the underlying substrate. The adhesion behavior of glial cells was almost independent of the biomaterial and the maximum growth areas were already seen after one day; however, adhesion dynamics of neurons relied on culture material and time. Neurons spread much better on TiN and nanocolumnar TiN and also formed more neurites after three days in culture. Our designed nanocolumnar TiN offers the possibility for building miniaturized microelectrode arrays for impedance spectroscopy without losing detection sensitivity due to a lowered self-impedance of the electrode. Hence, our results show that this biomaterial promotes adhesion and spreading of neurons and glial cells, which are important for many biomedical applications in vitro and in vivo.

Bimetallic copper-tin catalysts are considered cost-effective and suitable for large-scale electrochemical conversion of CO2 to valuable products. In this work, a class of tin (Sn) modified cuprous oxide (Cu2O) is simply synthesized through a one-pot microwave-assisted solvothermal method and thoroughly characterized by various techniques. Sn is uniformly distributed on the Cu2O crystals showing a cube-within-cube structure, and CuSn alloy phase emerges at high Sn contents. The atomic ratio of Cu to Sn is found to be crucially important for the selectivity of the CO2 reduction reaction, and a ratio of 11.6 leads to the optimal selectivity for CO. This electrode shows a high current density of 47.2 mA cm−2 for CO formation at −1.0 V vs. the reversible hydrogen electrode and also displays good CO selectivity of 80–90% in a wide potential range. In particular, considerable CO selectivity of 72–81% is achieved at relatively low overpotentials from 240 mV to 340 mV. During the long-term tests, satisfactory stability is observed for the optimal electrode in terms of both electrode activity and CO selectivity. The relatively low price, the fast and scalable synthesis, and the encouraging performance of the proposed material implies its good potential to be implemented in large-scale CO2 electrolyzers.

The organogermane GeH2Cp*2 (1) was synthesized by the reaction of GeCl2Cp*2 (A) with LiAlH4 in quantitative yield, whereas the synthesis of the previously reported compounds SiCl2Cp*2 (B), SnCl2Cp*2 (C), SiClHCp*2 (D) and SiH2Cp*2 (E) followed established routes. The molecular structures of the Cp*M(IV) derivatives 1, B, D and E are reported. In addition, compound 1 was characterized by spectroscopic methods such as 1H and 13C{1H} NMR spectroscopy, ATR-FTIR spectroscopy and EI-mass spectrometry. The thermal behavior of the germanes 1 and A was investigated by thermogravimetric analysis (TGA, DSC) and PXRD. The decomposition of compounds A and 1 starts at 270°C (A) and 200°C (1), respectively. The formation of crystalline Ge upon heating these compounds in sealed quartz glass capillaries was observed at 270°C (A) and 500°C (1).

We applied a method of plasma arc synthesis to study effects of modification of the fluorite phase of ceria by tin ions. By sputtering active components (Pt, Ce, Sn) together with carbon from a graphite electrode in a helium ambient we prepared samples of complex highly defective composite PtCeC and PtCeSnC oxide particles stabilized in a matrix of carbon. Subsequent high-temperature annealing of the samples in oxygen removes the carbon matrix and causes the formation of active catalysts Pt/CeOx and Pt/CeSnOx for CO oxidation. In the presence of Sn, X-Ray Diffraction (XRD) and High-Resolution Transmission Electron Microscopy (HRTEM) show formation of a mixed phase CeSnOx and stabilization of more dispersed species with a fluorite-type structure. These factors are essential for the observed high activity and thermic stability of the catalyst modified by Sn. X-Ray Photoelectron Spectroscopy (XPS) reveals the presence of both Pt2+ and Pt4+ ions in the catalyst Pt/CeOx, whereas only the state Pt2+ of platinum could be detected in the Sn-modified catalyst Pt/CeSnOx. Insertion of Sn ions into the Pt/CeOx lattice destabilizes/reduces Pt4+ cations in the Pt/CeSnOx catalyst and induces formation of strikingly high concentration (up to 50% at.) of lattice Ce3+ ions. Our DFT calculations corroborate destabilization of Pt4+ ions by incorporation of cationic Sn in Pt/CeOx. The presented results show that modification of the fluorite lattice of ceria by tin induces substantial amount of mobile reactive oxygen partly due to affecting geometric parameters of ceria by tin ions.

Living vegetation volume (LVV), one of the most difficult tree parameters to calculate, is among the most important factors that indicates the biological characteristics and ecological functions of the crown. Obtaining precise LVV estimates is, however, challenging task because the irregularities of many crown shapes are difficult to capture using standard forestry field equipment. Terrestrial light detection and ranging (T-LiDAR) can be used to record the three-dimensional structures of trees. The primary branches of Larix olgensis and Quercus mongolica in the Qingyuan Experimental Station of Forest Ecology at the Chinese Academy of Sciences (CAS) were taken as the research objects. A new rapid LVV estimation method called the filling method was proposed in this paper based on a T-LiDAR point cloud. In the proposed method, the branch point clouds are divided into leaf points and wood points. We used RiSCAN PRO 1.64 to manually separate the leaf points and wood points under careful visual inspection, and calculated that leaf points and wood points accounted for 91% and 9% of the number of the point clouds of branches. Then, the equation LVV = V1N (where N is the number of leaf points, and V1 is cube size) is used to calculate LVV. When the laser transmission frequency is 300,000 points/second and the point cloud is diluted to 30% using the octree method, the point cloud can be replaced by a cube (V1) of 6.11 cm3 to fill the branch space. The results showed that good performance for this approach, the measuring accuracy for L. olgensis and Q. mongolica at the levels of α = 0.05 and α = 0.01, respectively (94.35%, 90.01% and 91.99%, 85.63%, respectively). The results suggest that the proposed method can be conveniently used to calculate the LVV of coniferous and broad-leaf species under specific scanning settings. This work is explorative because hypotheses or a theoretical framework have not been previously defined. Rather, we would like to contribute to the formation of hypotheses as a background for further studies. [ABSTRACT FROM AUTHOR]

The rich and long-lasting Nordic Bronze Age was dependent throughout on incoming flows of copper and tin. The crucial turning point for the development of the NBA can be pinpointed as the second phase of the Late Neolithic (LN II, c. 2000–1700 BC) precisely because the availability and use of metal increased markedly at this time. But the precise provenance of copper reaching Scandinavia in the early second millennium is still unclear and our knowledge about the driving force leading to the establishment of the Bronze Age in southern Scandinavia is fragmentary and incomplete. This study, drawing on a large data set of 210 samples representing almost 50% of all existing metal objects known from this period in Denmark, uses trace element (EDXRF) and isotope analyses (MC-ICP-MS) of copper-based artifacts in combination with substantial typological knowledge to profoundly illuminate the contact directions, networks and routes of the earliest metal supplies. It also presents the first investigation of local recycling or mixing of metals originating from different ore regions. Both continuity and change emerge clearly in the metal-trading networks of the Late Neolithic to the first Bronze Age period. Artifacts in LN II consist mainly of high-impurity copper (so-called fahlore type copper), with the clear exception of British imports. Targeted reuse of foreign artifacts in local production is demonstrated by the presence of British metal in local-style axes. The much smaller range of lead isotope ratios among locally crafted compared to imported artifacts is also likely due to mixing. In the latter half of Nordic LN II (1800–1700 BC), the first signs emerge of a new and distinct type of copper with low impurity levels, which gains enormously in importance later in NBA IA. [ABSTRACT FROM AUTHOR]

The origin of the tin used for the production of bronze in the Eurasian Bronze Age is still one of the mysteries in prehistoric archaeology. In the past, numerous studies were carried out on archaeological bronze and tin objects with the aim of determining the sources of tin, but all failed to find suitable fingerprints. In this paper we investigate a set of 27 tin ingots from well-known sites in the eastern Mediterranean Sea (Mochlos, Uluburun, Hishuley Carmel, Kfar Samir south, Haifa) that had been the subject of previous archaeological and archaeometallurgical research. By using a combined approach of tin and lead isotopes together with trace elements it is possible to narrow down the potential sources of tin for the first time. The strongly radiogenic composition of lead in the tin ingots from Israel allows the calculation of a geological model age of the parental tin ores of 291 ± 17 Ma. This theoretical formation age excludes Anatolian, central Asian and Egyptian tin deposits as tin sources since they formed either much earlier or later. On the other hand, European tin deposits of the Variscan orogeny agree well with this time span so that an origin from European deposits is suggested. With the help of the tin isotope composition and the trace elements of the objects it is further possible to exclude many tin resources from the European continent and, considering the current state of knowledge and the available data, to conclude that Cornish tin mines are the most likely suppliers for the 13th–12th centuries tin ingots from Israel. Even though a different provenance seems to be suggested for the tin from Mochlos and Uluburun by the actual data, these findings are of great importance for the archaeological interpretation of the trade routes and the circulation of tin during the Late Bronze Age. They demonstrate that the trade networks between the eastern Mediterranean and some place in the east that are assumed for the first half of the 2nd millennium BCE (as indicated by textual evidence from Kültepe/Kaneš and Mari) did not exist in the same way towards the last quarter of the millennium. [ABSTRACT FROM AUTHOR]

Introduction: Our objective was to assess whether clusters of centers with similar peritoneal dialysis (PD) catheter related practices were associated with differences in the risk of technique failure. Methods: Patients on incident PD in French centers contributing to the French Language PD Registry from 2012 to 2016 were included in a retrospective analysis of prospectively collected data. Centers with similar catheter cares practices were gathered in clusters in a hierarchical analysis. Clusters of centers associated with technique failure were evaluated using Cox and Fine and Gray models. A mixed effect Cox model was used to assess the influence of a center effect, as explained by the clusters. Results: Data from 2727 catheters placed in 64 centers in France were analyzed. Five clusters of centers were identified. After adjustment for patient-level characteristics, the fourth cluster was associated with a lower risk of technique failure (cause specific-HR 0.70, 95%CI 0.54–0.90. The variance of the center effect decreased by 5% after adjusting for patient characteristics and by 26% after adjusting for patient characteristics and clusters of centers in the mixed effect Cox model. Favorable outcomes were observed in clusters with a greater proportion of community hospitals, where catheters were placed via open surgery, first dressing done 6 to 15 days after catheter placement, and local prophylactic antibiotics was applied on exit-site. Conclusion: Several patterns of PD catheter related practices have been identified in France, associated with differences in the risk of technique failure. Combinations of favorable practices are suggested in this study. [ABSTRACT FROM AUTHOR]