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The so-called tin pest is a phase transformation of white tin (P(Sn)) into grey tin (a(Sn)), where the disintegration of tin materials occurs due to different thermodynamic stability of the phases with a transition at 13.2 °C. In addition to temperature, another important factor influencing pest is the presence of impurities and alloying elements that can accelerate (Zn, Cu), retard (Pb, Au), or block (Bi, Sb) the degradation process. Experiments to date describe the influence of mostly one element present in the tin matrix or tin material used in industry. Historical materials often had not only different production technology but also imperfectly processed starting materials. Therefore, we first characterized real historical objects such as organ pipes, utensils and decorative objects using optical microscopy, XRF and XRD. We then observed the progression of the tin pest in the collected samples and used the course to determine the resulting effect of the combination of elements present. These data are of high value in conservation, where the non-destructively determined elemental composition can be used to decide which tin object is predisposed to succumb to tin pest and which is not. [ABSTRACT FROM AUTHOR]

The article discusses the possibility of a new method for processing tin-containing raw materials using a renewable carbon source - rice husks. A review of the literature on this topic showed the absence of publications on the possibility of using unconventional reducing agents in tin metallurgy. The work is devoted to filling the gap in the study of the possibility of using rice husks as a reducing agent in tin metallurgy. The process of pyrolysis of rice husks and reduction of tin oxide using rice husks were compared with traditional reducing agents, coal and coke. Heating was carried out in an inert atmosphere (argon). Thermal effects were studied using thermogravimetric analysis and differential scanning calorimetry. The optimal heating rate (5 °C/min) with the maximum decomposition of rice husks (up to 82 %) was found experimentally. It was found that the reduction of SnO2 with coal and rice hulls begins already at ≥ 800 °C, while interaction with coke does not occur even at 900 °C and above. Rice husks have been proven a promising reductant for SnO2. [ABSTRACT FROM AUTHOR]

Electrochemical behaviour can be improved by decreasing the size of anode materials. In this work, the surface stability, surface adsorption and surface intercalation of nanoscale β-tin (β-Sn) and bismuth (Bi) as anode materials for magnesium (Mg) ion batteries (MIBs) were studied using first-principle calculations. The results show that the (100) and (111) surfaces are energetically stable for β-Sn and Bi, respectively. The diffusion of Mg from the surface to the inside through the Sn (100) surface was not affected by the appearance of the surface, whereas a rate-liming step appears for the Mg diffusion from the surface to the subsurface in Bi. Surface modification is necessary to improve the electrochemical behaviour of Bi as an anode for MIBs. [ABSTRACT FROM AUTHOR]

In this study, a series of Y 2 B 2 O 7 compounds with a fixed Yttrium cation A site but with different B (B Ti, Sn, Zr and Ce) sites have been synthesized and used to support Ni for methane reforming for hydrogen production. By replacing the B site with Ti, Sn, Zr and Ce cations in sequence, the r A /r B ratios of the resulted Y 2 B 2 O 7 compounds become smaller. As a consequence, the crystalline structures of the compounds become less ordered with the transformation of the bulk phase from well-ordered pyrochlore (Y 2 Ti 2 O 7 ) to less ordered pyrochlore (Y 2 Sn 2 O 7 ) and subsequently to defective fluorite (Y 2 Zr 2 O 7 and Y 2 Ce 2 O 7 ). XPS results have revealed that on the surfaces of Ni/Y 2 Ti 2 O 7 and Ni/Y 2 Ce 2 O 7 , higher O/(Y + B) atomic ratios can be achieved than on the other two catalysts, indicating the presence of more abundant oxygen species, which is beneficial to remove the carbon deposits. In comparison with Y 2 Zr 2 O 7 and Y 2 Ce 2 O 7 , the supported Ni or Ni 3 Sn 2 active sites have stronger interaction with Y 2 Ti 2 O 7 and Y 2 Sn 2 O 7 supports, which anchors the active sites tighter on the supports and suppresses its aggregation effectively, thus obtaining catalysts with larger active metallic surface areas and better thermal stability. As a result, the stability and coking resistance of the catalysts can be enhanced. For the reduced Ni/Y 2 Sn 2 O 7 , Ni 3 Sn 2 alloy has formed, which improves the coking resistance of the catalyst but degrades its activity significantly. On Ni/Y 2 Ti 2 O 7 catalyst, which possesses the largest amount of active surface oxygen species, the strongest Ni interaction with the support can also be obtained, therefore, it exhibits the highest activity, stability and strongest coking resistance among all of the catalysts. [ABSTRACT FROM AUTHOR]

Sn-Mg co-substituted M-type SrCaLa hexaferrites Sr 0.5 Ca 0.2 La 0.3 Fe 12.0−2x (SnMg) x O 19 (0.0 ≤ x ≤ 0.5) have been synthesized by ball milling and calcining. The results of X-ray diffraction show that a single magnetoplumbite phase is exhibited in all the samples and no impurity phase is observed in the structure. Lattice constants ( c and a ) increase with increasing Sn-Mg content (x) from 0.0 to 0.5. Platelet like structure exhibited by FE-SEM micrographs confirms the hexagonal structure of the synthesized samples. The saturation magnetization ( M s ) first increases with increasing SnMg content (x) from 0.0 to 0.1, and then decreases when Sn-Mg content (x) ≥ 0.1. The remanent magnetization ( M r ), M r / M s ratio, coercivity ( H c ), magnetic anisotropy field ( H a ) and first anisotropy constant ( K 1 ) decrease with increasing Sn-Mg content (x) from 0.0 to 0.5. [ABSTRACT FROM AUTHOR]

Aconcentrate obtained frommining tailings containingmainly cassiterite and columbotantalite was reduced for the production of tin metal. The compounds CaCO3, Na2CO3, K2CO3, and borax were used as fluxes in the pyrometallurgical reduction smelting process, and graphite was employed as the reducing agent. The greatest recovery of Sn (>95%) was obtained when using CaCO3 as the flux; the purity of Sn was 96%. A slag equivalent to 25% of the mass of the initial concentrate was produced during the recovery of the Sn. This contained 45% Nb2O5 and Ta2O5, adding extra value to the mine tailings. The tin metal ingot was purified by electrorefining involving a tin and H2SO4 electrolyte solution and a 101.9 A/m2 current applied for 148 h. Under these conditions, 90 wt % of the Sn in the ingot was recovered at a purity of 99.97%. [ABSTRACT FROM AUTHOR]

Examples of tin dications without closer contacts to the anion are rare, as are straightforward routes to weakly coordinated tin(ii) dication salts. Here we report on the synthesis of [Sn(MeCN)6][Al(ORF)4]2 (RF = C(CF3)3) via NO+-oxidation of tin metal. Subsequently, [Sn(MeCN)6][Al(ORF)4]2 was used to prepare the mixed coordinated [Sn(pyr)2(MeCN)4][Al(ORF)4]2 and [Sn(PPh3)2-(MeCN)5][Al(ORF)4]2·MeCN. Additionally, [Sn(dmap)4][Al(ORF)4]2 was prepared via a reaction of dmap with [SnCp][Al(ORF)4]. The generality of the formation of tin(ii) dications by reacting [SnCp]+ and L to give [SnLx]2+ and SnCp2 was investigated using DFT calculations. Extensions to [ECp*]+ cations (E = Si, Ge, Sn, and Pb) are also suggested to be useful for the preparation of E(ii) dications. [ABSTRACT FROM AUTHOR]

The diffusion barrier properties of Sc2O3 against metal diffusion were studied. Tin and ruthenium were used as probe materials to study the barrier properties of Sc2O3 in thickness ranges that are of relevance for gate materials. Tin deposition and hydrogen radical etching from Sc2O3 layers of 0.5-1.5 nm thickness, deposited on Ru, show that these Sc2O3 layers effectively block the diffusion of Sn into Ru. We show that Sn adhesion and etching depends strongly on the thickness of the Sc2O3 film. The etch-rate is found to be inversely proportional to the Sc2O3 layer thickness, which we attribute to Sc2O3 becoming a more effective charge transfer barrier at larger thicknesses. [ABSTRACT FROM AUTHOR]

The intertwined TiN nanofibers with mesopores structure were fabricated by an electrospinning method followed by a nitridation reaction. TiN nanofibers counter electrodes (CEs) based DSC delivered dramatically enhanced photovoltaic performances, compared with particulate TiN CE. The nanofibers intertwined to form a 3D conducting pathway facilitating the electron transfer, while the tunable surface areas and mesoporous provided abundant catalytic active sites and reduced the diffusion impedance of triiodide ions, leading to the high J SC and FF for DSCs. Based on these advantages, the highest conversion efficiency of devices employing TiN nanofibers CEs yielded 7.08%, which was higher than that of device with Pt CE (6.84%). Therefore, the facile procedure, low cost and excellent photovoltaic properties endow the intertwined TiN nanofibers to be a promising alternative CE for future large-scale application of DSCs. [ABSTRACT FROM AUTHOR]

The accuracy of the baseline evaluation is of importance for calculating the transition enthalpy such as the latent heat of the crystallization. This study demonstrates the modified method of the equivalent non-latent heat baseline, by which the transition enthalpy can be measured accurately according to the transition peak in differential scanning calorimetric curve. With this method, the effect of melt superheating treatment time on the latent heat release upon the solidification of tin is investigated. The results show that the latent heat increases by increasing the treatment time, and is close to a constant when the treatment time is large enough, indicating the homogeneous system. And then, a simple model is established to describe the changes of the crystallization latent heat with the treatment time, which is confirmed by the experimental data of Sn. [ABSTRACT FROM AUTHOR]

Während des letzten halben Jahrhunderts hat die Anzahl und die Genauigkeit von experimentellen Verfahren, welche imstande sind, Werte von beobachtbaren Größen für biomolekulare Systeme zu liefern, stetig zugenommen. Die Umwandlung eines Messwerts Qexp einer beobachtbaren Größe Q in strukturelle Information stellt jedoch eine Aufgabe dar, welche theoretische und praktische Probleme mit sich bringt: 1) mangelhafte oder ungenaue Werte Qexp, 2) Ungenauigkeiten im verwendeten funktionalen Zusammenhang Q(r→) , zur Verknüpfung der Größe Q mit der Struktur r→ , 3) die Beschreibung der messungsinhärenten Mittelung von Qexp, 4) die Handhabung einer mehrdeutigen Umkehrfunktion r→(Q) zur Funktion Q(r→) , um nur einige zu nennen. Diese Problemstellungen treffen auf eine Vielzahl beobachtbarer Größen Q und Messverfahren zu, wie z. B. Röntgen‐ und Neutronenbeugung, Kleinwinkel‐ und Weitwinkel‐Röntgenstreuung, Bildgebung mittels Freier‐Elektronen‐Laser, Kryo‐Elektronenmikroskopie, Kernspinresonanz, paramagnetische Elektronenresonanz, Infrarot‐ und Raman‐Spektroskopie, Zirkulardichroismus, Förster‐Resonanz‐Energietransfer, Rasterkraftmikroskopie und Ionenmobilitäts‐Massenspektrometrie. Das Vorgehen, Strukturinformation aus Messdaten zu gewinnen, wird anhand von Beispielen aus der Literatur, welche die Auswirkungen der vielfältigen zu treffenden Entscheidungen und Näherungen aufzeigen, besprochen. Die Ausführungen richten sich dabei in erster Linie an Nichtexperten und Anfänger auf dem Gebiet. Eine Auflistung an Entscheidungen, die es zu vermeiden gilt, wird bereitgestellt. Die richtige Entscheidung treffen: Die Bestimmung von Strukturinformation aus experimentellen Messdaten stellt eine Aufgabe dar, die theoretische und praktische Probleme mit sich bringt. Der Einfluss der vielfältigen Annahmen und Näherungen, die in den Prozess der biomolekularen Strukturaufklärung Eingang finden, wird diskutiert und eine Auflistung von Entscheidungen, die es zu vermeiden gilt, wird bereitgestellt. [ABSTRACT FROM AUTHOR]

An organocatalytic, highly facile, efficient, and regioselective ortho-chlorination of anilines is described. A secondary ammonium chloride salt has been employed as the catalyst and the reaction can be conducted at room temperature without protection from air and moisture. In addition, the reaction is readily scalable and the catalyst can be recycled and reused. This catalytic protocol has been applied to the efficient synthesis of a highly potent c-Met kinase inhibitor. Mechanistic studies revealed that unique structural features of the secondary ammonium chloride salt are important for both the catalysis and regioselectivity of the electrophilic ortho-chlorination. [ABSTRACT FROM AUTHOR]

The reactions of SnR 2 Cl 2 (R = Me, Bu or Ph) with sodium 4-phenylbutyrate, NaO 2 C(CH 2 ) 3 Ph (NaOPh b ), yielded three organotin carboxylates, namely [{(Me 2 SnOPh b ) 2 O} 2 ] ( 1 ), [Bu 2 Sn(OPh b ) 2 ] ( 2 ) and [{PhSn(O)OPh b } 6 ] ( 3 ). Complexes ( 1 ) and ( 2 ) have been spectroscopically authenticated by FT-IR, 119 Sn Mössbauer, and 1 H, 13 C{ 1 H} and 119 Sn{ 1 H} NMR techniques. In addition, the crystallographic structures of ( 1 )–( 3 ) have been determined by X-ray diffraction measurements. Complex ( 1 ) displays two signals in the solution 119 Sn NMR spectrum corresponding to the exo ( δ −176.3) and endo cyclic ( δ −188.4) SnMe 2 moieties, whereas ( 2 ) exhibits only one 119 Sn resonance ( δ −148.1). The crystallographic characterization of ( 1 ) confirms the centrosymmetric tetranuclear stannoxane structure and the existence of the exo and endo cyclic SnMe 2 moieties in the both distorted trigonal bipyramidal and octahedral environment, respectively. Complex ( 2 ) crystallises as a monomer in which the Sn(IV) cation lies at the centre of a distorted octahedron. The bonding scheme in ( 3 ) outlines a hexanuclear drum-like structure comprising two six-membered (–Sn–O–) 3 stannoxane rings. The supramolecular arrangements of ( 1 )–( 3 ) result from noncovalent interactions, namely Sn⋯O ( 1 ) and ( 2 ), C–H⋯π ( 1 ), and C–H⋯O ( 1 )–( 3 ). Finally, antifungal activities of all organotin derivatives have been screened against Candida albicans (ATCC 18804), Candida tropicalis (ATCC 750), Candida glabrata (ATCC 90030), Candida parapsilosis (ATCC 22019), Candida lusitaniae (CBS 6936), and Candida dubliniensis (clinical isolate 28). Complex ( 2 ) exhibited the best biocide activity amongst the three organotin products. [ABSTRACT FROM AUTHOR]

The efficacy of tin-nitrogen codoping (Sn N) in ZnO thin films deposited on glass substrates by spray pyrolysis technique to achieve a p type transparent conductive material is investigated. Monodoping ZnO with N altered the conductivity type but the resistivity is too high making it practically impossible to be useful in optoelectronic applications. But Sn N codoping increased the hole concentration and obtained comparatively low resistivity because codoping enhanced the acceptor incorporation by forming acceptor-donor-acceptor complex in the band gap. The XRD analysis revealed the dependence of dopant incorporation on the texture and microstructure of the ZnO thin films. Further, the optical energy gap of N doped film decreased compared to undoped one due to the merging of impurity bands with the valence band while higher energy gap value for codoped film which might be due to the Burstein-Moss effect arising from increase in carrier concentration and also due to degraded crystallinity. [ABSTRACT FROM AUTHOR]

Copper-deficient copper sulfide (Cu2-xS) nanoparticles (NPs) have been investigated as important hole-based plasmonic materials because of their size, morphology, and carrier density-dependent localized surface plasmon resonance (LSPR) properties. Morphology and carrier density are two important parameters to determine their LSPR properties. Here, we demonstrate that the foreign metal ion, Sn4+, directs the growth of djurleite Cu31S16 from nanodisk to tetradecahedron along the [100] direction. To control the LSPR properties by tuning the carrier density, the djurleite Cu31S16 nanoparticles were pseudomorphically converted into more copper-deficient (higher carrier density) roxbyite Cu7S4 NPs by heat treatment in the presence of amine. The roxbyite Cu7S4 NPs exhibited a shorter and stronger LSPR peak while retaining the morphology of the djurleite Cu31S16 NPs. [ABSTRACT FROM AUTHOR]

Polycrystalline BiFeO $_{\mathrm {\mathbf {3}}}$ and Bi $_{\mathrm {\mathbf {0.9}}}$ Gd $_{\mathrm {\mathbf {0.1}}}$ Fe $_{\boldsymbol {1-}\boldsymbol {{x}}}$ Ti O ( x = 0, 0.01, 0.05 and 0.1) samples were synthesized by solid-state reaction route. Structural, magnetic and ferroelectric properties of these samples were investigated. X-ray powder diffraction (XRD) results confirmed the presence of a significant amount of Bi $_{\mathrm {\mathbf {2}}}$ Fe $_{\mathrm {\mathbf {4}}}\textit {O}_{\mathrm {\mathbf {9}}}$ impurity phase in the undoped BiFeO $_{\mathrm {\mathbf {3}}}$ sample. Mössbauer spectroscopy studies corroborated the XRD studies to confirm the presence of impurity phase. We have observed that gadolinium (Gd $^{\boldsymbol {3+}}$ ) and titanium (Ti $^{\boldsymbol {4+}}$ ) doping, respectively, on Bi $^{\boldsymbol {3+}}$ and Fe $^{\boldsymbol {3+}}$ sites facilitated a significant reduction in the impurity phase formation in BiFeO $_{\mathrm {\mathbf {3}}}$ . Interestingly, Gd $^{\boldsymbol {3+}}$ -doping significantly reduced the impurity phase formation as compared to the undoped BiFeO $_{\mathrm {\mathbf {3}}}$ sample. This impurity phase formation was further overcome by doping higher ( x $\boldsymbol {\ge } $ 0.05) amounts of Ti in BiFeO $_{\mathrm {\mathbf {3}}}$ . The crystallographic site occupancies of Gd and Ti were confirmed by Rietveld refinement of XRD data, Mössbauer spectroscopy and magnetization measurements. An enhancement in ferromagnetic properties along with moderate ferroelectric properties have been observed after co-doping. There was an increasing trend in remnant polarization ( P $_{\mathrm {\mathbf {r}}}$ ) with the increase in Ti concentration besides an improvement in the characteristic saturation magnetization. Our results demonstrate that Gd $^{\boldsymbol {3+}}$ and Ti $^{\boldsymbol {4+}}$ doping could be used to enhance multifunctional properties of BiFeO $_{\mathrm {\mathbf {3}}}$ ceramics to enable them as potential material for various devices. [ABSTRACT FROM AUTHOR]

Degradation kinetics of iohexol by UV/chlorine advanced oxidation process (AOP) and the formation of iodinated trihalomethanes (I-THMs) during post-chlorination were investigated in this study. Iohexol, a commonly detected iodinated contrast media in water, can be effectively removed during UV/chlorine process with pseudo-first-order reaction kinetics due to the combination of UV photolysis and oxidation of hydroxyl radicals. The second-order rate constant between iohexol and hydroxyl radicals was determined as 3.8 × 10 9 M −1 s −1 by competition kinetic experiment. Five intermediates were identified by ultra performance liquid chromatography–electrospray ionization-mass spectrometry analysis and degradation pathways of iohexol during UV/chlorine were proposed. Effects of chlorine dose, pH and bromide concentration on iohexol degradation and I-THM formation during post-chlorination were also studied. The results showed that iohexol degradation was accelerated with the increase of chlorine concentration as well as the decrease of pH and bromide concentration. On the other hand, I-THM formation from post-chlorination of UV/chlorine treated iohexol favored relatively low chlorine doses, high bromide concentrations at circumneutral conditions. Raw water experiments showed that I-THM formation after post-chlorination of UV/chlorine-treated iohexol was lower compared to that from UV irradiation, indicating that UV/chlorine is superior to UV alone in controlling I-THM formation. [ABSTRACT FROM AUTHOR]

The reaction between cesium iodide (CsI) and chlorine gas was quantitatively investigated using a thermo-gravimetric analysis system. A comparison between calculated and experimental results on the chlorine molar flow rate revealed that the reaction lies within the gas phase diffusion limited region under the condition of this work. Using the experimental data, the second-order nucleation and growth model was identified as the best geometry function to describe the morphological changes of CsI during the chlorination reaction. Combining the gas phase diffusion equation and geometry function, a reaction rate equation was proposed for the reaction between CsI and Cl. [ABSTRACT FROM AUTHOR]

There are very few studies that have investigated directly the effect of an oxide film on tin whisker growth, since the 'cracked oxide theory' was proposed by Tu in 1994 [K.-N. Tu: Phys. Rev., 1994, 49, (3), 2030-2034]. The current study has investigated the effect of an electrochemically produced oxide on tin whisker growth, for both Sn-Cu electrodeposits on Cu and pure Sn electrodeposits on brass. X-ray photoelectron spectroscopy (XPS) has been used to investigate the effect of the applied electrochemical oxidation potential on the oxide film thickness. Focused ion beam has been used to prepare cross sections from electrodeposited samples to investigate the influence of the electrochemically formed oxide film on deposit microstructure during long-term room temperature storage. The XPS studies show that the thickness of electrochemically formed oxide film is directly influenced by the applied potential and the total charge passed. Whisker growth studies show that the electrochemical oxidation treatment mitigates whisker growth for both Sn-Cu electrodeposits on Cu and pure Sn electrodeposits on brass. For Sn electrodeposits on brass, the electrochemically formed oxide greatly reduces both the formation of zinc oxide at the surface and the formation of intermetallic compounds, which results in the mitigation of tin whisker growth. For Sn-Cu electrodeposits on Cu, the electrochemically formed oxide has no apparent effect on intermetallic compound formation and acts simply as a physical barrier to hinder tin whisker growth. [ABSTRACT FROM AUTHOR]

Zr-substituted SnO-based ceramics (SnSbZrO, x ≤ 0.1) were prepared by using a wet-chemical synthesis method. The results show that the prepared ceramics have a pure tetragonal phase as that of SnO and have a typical characteristic of negative temperature coefficient (NTC) of resistivity over a wide temperature range from −50 to 300 °C. The room-temperature resistivity ρ and material constant B of the NTC thermistors increase from 4.77 Ω cm to 4.89 × 10 Ω cm and from 641 to 5085 K, respectively, when the content of Zr, x, changes from 0 to 0.1. The NTC thermistors also show high cyclic stability and ageing resistance. The analysis of impedance spectra reveals that the NTC effect mainly resulted from the grain-boundary contribution, and the conduction mechanisms of the SnSbZrO thermistors combine with the electron-hopping conduction and band conduction. [ABSTRACT FROM AUTHOR]

Room-temperatureionic liquids (RTILs) constitute a fine-tunableclass of compounds. Morpholinium-based cations are new to the field.They are promising candidates for electrochemistry, micellization,and catalytic applications. We investigate halogenation (fluorinationand chlorination) of the N-ethyl-N-methylmorpholinium cation from the thermodynamics perspective. Wefind that substitutional fluorination is much more energetically favorablethan substitutional chlorination, although the latter is also a permittedprocess. Although all halogenations at different locations are possible,they are not equally favorable. Furthermore, the trends are not identicalin the case of fluorination and chlorination. We link the thermodynamicobservables to electron density distribution within the investigatedcation. The reported insights are based on the coupled-cluster technique,which is a highly accurateand reliable electron-correlation method. Novel derivatives of themorpholinium-based RTILs are discussed, motivating further effortsin synthetic chemistry. [ABSTRACT FROM AUTHOR]

In this work, we investigate Tin (Sn) as a high capacity Li + host material and perform an ex situ study with X-ray microtomography characterizing in three-dimensions (3D) Sn particle deformation during the crucial first cycles of lithiation/delithiation. We combine in-house algorithms with commercial software to develop 3D visualizations and measurements showing radial particle fracture, non-uniform lithiation of Sn particles, and a link between the global change in image intensity and loss of capacity. Particle size dependent “effective” volume expansion between 200% and 450% was measured during lithiation, and effective volume reductions of 50% were measured during delithiation. Relationships between the gray scale intensity change, volumetric expansion and particle size during the first cycle are also illustrated. [ABSTRACT FROM AUTHOR]

The tin metal could be retractable from wasted tin scrap, sludge, and wasted electroplated solution hydrometallurgical treatment, and purification process. In order to be used as resource of electronic devices, the retracted crude metal should be purified to the extent of higher than 99.9%. In this study, tin electro-refining process was performed to purify the casted tin crude metal at various experimental conditions: at the current density of 3, 5A/dm2, and in various electrolytes such as hydrochloric acid, sulfuric acid and methansulfonic acid. Additional experiment was conducted using Rotating Disk Electrode (RDE) in order to investigate the rate determining step of tin electro-refining process. The current efficiency, 65.6%, was achievable at the condition of current density, 5A/dm2, and in the electrolyte of Hydrochloric acid. During tin electro-refining process, impurity dissolved from tin crude metal into the electrolyte was analyzed using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES), and the result showed the concentration of impurity metal gradually increased. Quantitative analysis on casted tin crude metal showed that it consists of tin with 93.9 wt.% and several impurity metals of Ag, Bi, Pb, Cu, and etc. After tin electro-refining process, the purity of tin increased up to 99.985 wt.%. [ABSTRACT FROM AUTHOR]

Single crystals of Yb14-xCexMnSb11 were grown from tin metal as a flux solvent with a maximum Ce incorporation of 0.6. The phases with x ~ 0.1-0.6 crystallize in the tetragonal Ca14AlSb11 structure type with I41/acd space group. In this structure type, there are 4 crystallographically unique Yb sites and the structure can be described according to the Zintl concept as containing 14Yb2+ + [MnSb4]9- + [Sb3]7- + 4Sb3-. For x > 0.3, Ce is incorporated on specific Yb sites in the structure as a function of x, initially at x = 0.3 on the Yb(2) site followed by Yb(4) at higher values of x. These sites have the largest volume as indicated by Hirshfeld surface analysis of chemical bonding. As Ce content is increased, the ferromagnetic ordering temperatures decrease and effective paramagnetic moments increase. The magnetic ordering temperatures decrease from the undoped TC of 50 K until x ~ 0.4, where the lowest TC of 39 K is reached. As the additional electron introduced by Ce3+ fills the hole associated with [MnSb4]9-, the screening of the Mn moments is reduced. This leads to an increase in overall moment attributed to Mn in addition to the moment from the Ce3+ f electron. Increasing Ce content also leads to an increase in electrical resistivity, an expected effect from reducing the carrier concentration. [ABSTRACT FROM AUTHOR]

The activities of components of Sn-Zn system were predicted based on the molecular interaction volume model (MIVM). The separation coefficients and the vapor-liquid phase equilibrium of Sn-Zn system were also predicted using the MIVM. The predicted results indicated that the content of tin in the vapor phase was 0.000052 wt pct, while in the liquid phase, it was 99.98 wt pct at 1173 K (900 °C). Experimental investigations into the separation of Sn-Zn alloy by vacuum distillation were carried out for the proper interpretation of the predicted results. The effects of vacuum level (15 to 200 Pa), distillation temperatures [873 K to 1273 K (600 °C to 1000 °C)], and soaking time (20 to 60 minutes) were studied. The experimental results indicated that the content of tin in the vapor phase was 0.001 wt pct, while in the liquid phase, it was 99.98 wt pct at 1173 K (900 °C). The experimental results match well with the predicted data, suggesting that the MIVM is a suitable model for Sn-Zn system. [ABSTRACT FROM AUTHOR]

Indium–tin carboxylate precursors were successfully synthesized by a direct reaction of indium and tin metals with a molten fatty acid under a nitrogen atmosphere at 260 °C. A linear relationship between the reaction initiation temperature and the number of carbon atoms of the fatty acids ranging from capric acid to stearic acid was observed. There was a 7 °C increase in the reaction initiation temperature for an increase of one carbon atom in the fatty acid. Nearly monodisperse 7–9 nm ITO nanocrystals without agglomeration were synthesized by direct pyrolysis of the as-synthesized precursors without using additional organic solvents. The fatty acid had a minor effect on the decomposition temperature and the mean ITO particle size, but affected the particle size distribution. TOF-SIMS data confirmed that the residue fatty acids on the surface of the indium tin oxide (ITO) nanoparticles served as a built-in surfactant leading to excellent dispersity of the ITO nanocrystals in non-polar solvents. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the synthesis of tin nanoparticles (NPs) or tin/carbon composites, in room temperature ionic liquids (RTILs), that could be used as structured anode materials for Li-ion batteries. An innovative route for the synthesis of Sn nanoparticles in such media is successfully developed. Compositions, structures, sizes and morphologies of NPs were characterized by high-energy X-ray diffraction (HEXRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). Our findings indicated that (i) metallic tetragonal ß-Sn was obtained and (ii) the particle size could be tailored by tuning the nature of the RTILs, leading to nano-sized spherical particles with a diameter ranging from 3 to 10 nm depending on synthesis conditions. In order to investigate carbon composite materials for Li-ion batteries, Sn nanoparticles were successfully deposited on the surface of multi-wall carbon nanotubes (MWCNT). Moreover, electrochemical properties have been studied in relation to a structural study of the nanocomposites. The poor electrochemical performances as a negative electrode in Li-ion batteries is due to a significant amount of RTIL trapped within the pores of the nanotubes as revealed by XPS investigations. This dramatically affected the gravimetric capacity of the composites and limited the diffusion of lithium. The findings of this work however offer valuable insights into the exciting possibilities for synthesis of novel nano-sized particles and/or alloys (e.g. Sn-Cu, Sn-Co, Sn-Ni, etc.) and the importance of carbon morphology in metal pulverization during the alloying/ dealloying process as well as prevention of ionic liquid trapping. [ABSTRACT FROM AUTHOR]

he identity of the predominating tin(II)-hydroxide complex formed in hyper-alkaline aqueous solutions (0.2 ≤ CNaOH ≤ 12 mol dm-3) is determined by potentiometric titrations, Raman, Mössbauer and XANES spectroscopy, supplemented by quantum chemical calculations. Thermodynamic studies using a H2/Pt electrode up to free hydroxide concentrations of 1 mol dm-3 showed the presence of a single monomeric complex with a tin(II) : hydroxide ratio of 1 : 3. This observation together with Raman and Mössbauer spectroscopic measurements supplemented by quantum mechanical calculations proved that the predominating complex is [Sn(OH)3]-, and that the presence of the other possible complex, [SnO(OH)]-, could not be proven with either experiments or simulations. The structure of the trihydroxidostannate(II) complex, [Sn(OH)3]-, was determined by EXAFS and was found to be independent of the applied hydroxide and tin(II) concentrations. The mean Sn-O bond distance is short, 2.078 Å, and in very good agreement with the only structure reported in the solid state. It is also shown that at pH values above 13 the speciation of the predominant trihydroxidostannate(II) complex is not affected by the presence of high concentrations of chloride ions. [ABSTRACT FROM AUTHOR]

We report an investigation on X-ray diffraction simulation of GeSn/Ge Multi-quantum wells (MQWs) with kinematic approach. X-ray diffraction in (004) ω-2θ scan and (224) reciprocal space mapping are performed for characterization of the MQWs. However, simulation of the diffraction process is imperative for further structural analysis of the MQWs. The compressive strain not only affects the calculation of Sn composition in GeSn wells, but also dramatically affects the symmetry of satellite peaks. [ABSTRACT FROM AUTHOR]

This study is planned to report the advancement of green microwave approach in the fabrication of a new series of biologically potent (NX, where X = O/S) donor Schiff bases and their cadmium(II) and tin(II) complexes. The ligands and their metal complexes have been characterized in terms of elemental analysis, molar ionic conductance, magnetic moment and spectral (IR, UV-Vis, NMR (1H, 119Sn), FAB-mass, thermal and XRD) data. The data revealed that the ligands coordinated to the metal center via nitrogen and oxygen/sulfur atoms and form an octahedral arrangement of the ligands around central metal atom. All compounds were evaluated for their in vitro antimicrobial activities against two pathogenic bacteria Bacillus subtilis and Escherichia coli and two fungi Aspergillus niger and Aspergillus flavus by standard disc diffusion method. The discs were stored in an incubator at 37 °C. The compounds were dissolved in DMF at 500 and 1000 ppm concentrations for screening biocidal activity. The compounds were dissolved in DMF to get the 100 and 200 ppm concentration of test solutions for screening fungicidal activity. The inhibition zone around each disc was measured (in mm) after 24 h and 96 h for biocidal and fungicidal activities respectively. [ABSTRACT FROM AUTHOR]

Tin sulfide films were deposited from an aqueous solution of tin dichloride, thiacetamide, and disodium citrate. X-ray diffraction, atomic force microscopy, ultraviolet–visible spectrophotometry, and electrical measurement were used to characterize the films. The films directly deposited at 70 and 80 °C for 1 and 2 h showed thicknesses of 70–400 and 120–650 nm, respectively. But the deposition at 40 °C for 1 h (nucleation step) made the films subsequently deposited at 60–80 °C denser and thicker (∼1600–7500 nm) than directly deposited films. Average transmittances of the films in UV–visible range decrease with increase in the thickness and are only in range of 0.33–2.3% for the films deposited with the nucleation step. The band gap energies of the films estimated from the transmittance spectra are in the range of ∼1.37–1.55 eV. Moreover, the films are p-type conductive. The electrical resistance and carrier mobility are in the ranges of 0.3–1.4 × 105Ω cm and 0.77–1.56 cm2(V s)−1, respectively. The films deposited with the nucleation step show lower resistance and higher carrier mobility than those deposited without nucleation because of their denser film microstructure and larger film thickness. [ABSTRACT FROM AUTHOR]

Pure Sn coatings are prepared by pulse current (PC) electrodeposition using aqueous acidic sulfate plating bath. The effects of various electroplating parameters such as current density, additive concentration, duty cycle, frequency, pH, bath temperature, and stirring rate (bath rotation) on the evolution of surface morphology of the coatings have been studied. The as-deposited coatings are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and surface profilometry. It is found that the current density, additive concentration, duty cycle, frequency, and pH have a major influence while temperature and stirring rate of the bath have a minor effect on the grain-size distribution. The mechanism involved in the morphology evolution and grain-size distribution due to the varying electroplating parameters has also been discussed. [ABSTRACT FROM AUTHOR]

The creep properties of P91 steel specimens undoped and doped with 0.058 wt pct tin, which was normalized from 1328 K (1055 °C) and tempered at 1033 K (760 °C), were examined under different engineering stresses (150 to 210 MPa) and temperatures [873 K to 923 K (600 °C to 650 °C)]. The creep behavior followed the temperature-compensated power law and Monkman-Grant equations. In the temperature-compensated power law equation, the apparent activation energy and stress exponent for creep were approximately 541 kJ/mol and 12 for the undoped steel and 527 kJ/mol and 11 for the Sn-doped one, respectively. In the Monkman-Grant relation, the values of constants m and C were around 1.062 and 0.0672 for the undoped steel, and 1.012 and 0.0650 for the Sn-doped one, respectively. The 100 MPa stress creep lifetime at 873 K (600 °C) was estimated as 100641 hours for the undoped steel and 35290 hours for the Sn-doped steel, respectively. These indicated that Sn substantially deteriorated the creep properties of the steel. It was found that grain or subgrain boundary segregation of Sn could promote the nucleation of cavities or microcracks, thereby leading to the deterioration of the steel creep properties. [ABSTRACT FROM AUTHOR]

The structure of a triclinic form of the organolithium derivative LiR, R = C(SiMe3)2(SiMe2{hpp}) (1) (hppH = 1,3,4,6,7,8,-hexahydro-2H-pyrimido[1,2-a]pyrimidine) comprises dimers [1]2 held together by Li-H3C interactions like those in the polymeric structure [1] ∞ of the previously described orthorhombic form. Compound 1 reacts with the chlorides MCl2 (M = Hg or Sn) to give compounds HgRCl (2) or SnRCl (3), which have been characterised by NMR spectroscopy and X-ray crystallography. The structural parameters and conformations of the metallacycles MRL[sub n] are compared with those in related compounds containing bulky organosilicon ligands with pendant nitrogen donors. Compound 3 reacts with Li[P{H}Ar[*]] (Ar[*] = 2,4,6-tBu3C6H2) to give the crowded phosphanide SnR(P{H}Ar*) (4). [ABSTRACT FROM AUTHOR]

Highlights: [•] Use of fungi is possible for material removal process. [•] Citric acid in the form of culture supernatant is responsible for material removal. [•] A cleaner material removal process can be developed. [Copyright &y& Elsevier]

We explore the effectiveness of tin (Sn), by alloying it with silicon, to use SiSn as a channel material to extend the performance of silicon based complementary metal oxide semiconductors. Our density functional theory based simulation shows that incorporation of tin reduces the band gap of Si(Sn). We fabricated our device with SiSn channel material using a low cost and scalable thermal diffusion process of tin into silicon. Our high-κ/metal gate based multi-gate-field-effect-transistors using SiSn as channel material show performance enhancement, which is in accordance with the theoretical analysis. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Highlights: [•] Role of recrystallization and its effect on reliability of lead free solder joints. [•] Effect of solder joint’s locations on the start and progress of recrystallization. [•] Effect of orientation of Sn grains on the start and progress of recrystallization. [•] Expected lifetime of different solder joint sizes also discussed in this paper. [ABSTRACT FROM AUTHOR]

For the synthesis of metalloid cluster compounds of tin applying the disproportionation reaction of subvalent metastable Sn(I) halides, Si(SiMe3)3 proved to be the ligand with the highest synthetic potential. However, degradation of the Si(SiMe3)3 ligand can also lead to cluster enlargement where additional silicon atoms are incorporated into the cluster core. Here we describe the structure and bonding of the novel anionic cluster compound {Sn10Si(SiMe3)2[Si(SiMe3)3]4}2- 5, where such a degradation has taken place. Additionally, requirements for the formation of 5 are discussed. [ABSTRACT FROM AUTHOR]

Complexes of Sn(II), Sn(IV), Ge(IV), and Si(IV) with the ambidentate pyridine-2-thiolato ligand (PyS-) were synthesized and characterized by multinuclear NMR spectroscopy and single-crystal X-ray diffractometry. Comparison of the structures of E(PyS)2Cl2 (E=Sn, Ge, Si) and E(PyS)4 (E=Sn, Si) allows for insights into the group 14 coordination chemistry of this ambidentate chelator in dependence of the thiophilicity of the central atom of the corresponding complex. Furthermore, the crystal structure of Sn(PyS)2 reveals two different coordination modes of its constituents, i.e., the crystal packing features cyclic dimers and polymeric chains of Sn(PyS)2. This compound was shown to undergo oxidative addition of 2,2′-dipyridyldisulfide and sulfur with the formation of Sn(PyS)4and (PyS)2Sn(μ-S)2Sn(PyS)2, respectively. [ABSTRACT FROM AUTHOR]

Abstract: An efficient asymmetric synthesis of homoallylic alcohols is described by the allylation of carbonyl compounds using organocatalysts as chiral directors in the presence of tin metal. The effect of chiral environment is also studied on the allylation reactions. This method allows us to obtain two different enantiomers of homoallylic alcohol in the presence of the corresponding chiral compound. The protocol is applied to various aldehydes to obtain high yields and excellent enantioselectivities for the corresponding homoallylic alcohols. [Copyright &y& Elsevier]

The Southeastern Yunnan region is one of the most important polymetallic ore districts in South China. Located in the southern margin of the South China Block, these ore districts are part of a wider granite-related magmatic-hydrothermal system. Laojunshan granite intrusions, located in the western part of the Southeastern Yunnan, are closely related to W-Sn mineralisation. In this paper we report zircon U-Pb ages, geochemical and petrological characteristics for the ore-related granites in Laojunshan area. Three samples from three intrusive suites of the granitic rocks in Laojunshan intrusion have been analyzed by the LA-ICPMS zircon U-Pb techniques, yielding ages of 86.66 ± 0.42 Ma, 86.72 ± 0.47 Ma and 86.02 ± 0.48 Ma, respectively. Bulk analysis reveals that three intrusive suites are strongly-peraluminous, silica-rich, aluminum-rich and alkali-rich granites and their ACNK values fall mainly into a small range of 1.10-1.38. Moreover, all granites show enriched Rb, La and Zr and depleted Ba, Sr and Ti, as well as a uniformly flat REE-pattern with a marked negative Eu anomaly. The granites and polymetallic W-Sn mineralization possibly both occurred during the Late Coniacian. [ABSTRACT FROM AUTHOR]

The reaction of Fe(CO) and BuSnH yielded the bimetallic cluster complexes Fe(μ-SnBu)(CO), 1, and Fe(μ-Sn)(μ-SnBu)(CO), 3. Compound 3 contains two Fe(CO)(μ-SnBu) groups held together by a central quadruply bridging tin atom, giving an overall bow-tie structure for the one tin and four iron atoms. Refluxing compound 1 in toluene solvent affords the complex Fe[μ-SnBu(CHPh)](CO), 4, where two of the Bu groups in 1 have been replaced with benzyl groups, as a result of selective benzylic C-H bond activation of solvent toluene. Similarly refluxing compound 1 in ortho-, meta- and para-xylene solvents gives the complexes where two, three and four of the Bu groups in 1 have been replaced by the respective xylyl groups. Compound 1 also reacts with ethylbenzene to furnish the complex Fe[μ-SnBu(MeCHPh)](CO), 14, where two of the Bu groups in 1 have been replaced as a result of the benzylic C-H activation of ethylbenzene. A mechanism based on a radical pathway is proposed for the selective C-H bond activation by 1. [ABSTRACT FROM AUTHOR]

Double Langmuir probe measurements are performed during the deposition of tin and chromium coatings in order to examine the degree of ionisation and the deviation from thermal equilibrium of these metal plasmas. [ABSTRACT FROM AUTHOR]

Granitic pegmatites are exceptional igneous rocks and the possible role of an immiscibility process in their origin is strongly debated. To investigate metal and metalloid behaviour in hydrous peraluminous systems (aluminium saturation index, ASI >1), we analysed 15 quartz-hosted primary melt and fluid inclusions from pegmatites in the Ehrenfriedersdorf Complex (Erzgebirge, Germany) and 26 primary melt inclusions from leucogranites of the Ehrenfriedersdorf district (Germany), Kymi (Finland) and Erongo (Namibia) by femtosecond laser ablation inductively coupled plasma quadrupole mass spectrometry. The results presented here for 32 elements provide evidence for metal and metalloid fractionation between two types of immiscible melts (A and B) and NaCl-HCl-rich brine in the pegmatite system. No evidence for the boundary layer effect was observed in the 40-500 pm size melt inclusions that were investigated. The data on the Ehrenfriedersdorf pegmatites allow quantification of the metal and metalloid partitioning between natural NaCl-rich brine and the two types of melt (e.g. Kbrine/type-A,BAs = 0.01 - 1.7; Kbrine/type-A,BAs = 10 - 285; Kbrine/type-A,BZn ≥ 50; Kbrine/type-A meltPb ≥ 50; Kbrine/type-A meltAg = 46. These data are in accord with existing natural and experimental data on equilibrium fluid-melt partitioning as well as spectroscopic data on the metal and metalloid complexation in hydrous aluminosilicate melts and NaCl-HCl-rich fluids. [ABSTRACT FROM AUTHOR]

Intermetallic compounds formed during the liquid-solid interfacial reaction of Sn-Ag and Sn-Ag-In solder bumps on Cu under bump metallization at temperatures ranging from 240 to 300 °C were investigated. Two types of intermetallic compounds layer, η CuSn type and ε CuSn type, were formed between solder and Cu. It was found that indium addition was effective in suppressing the formation of large AgSn plate in Sn-Ag solder. During interfacial reaction, Cu consumption rate was mainly influenced by superheat of solder, contact area between solder and Cu and morphology of intermetallic compounds. The growth of η intermetallic compounds was governed by a kinetic relation: ΔX = t, where the exponent n values for Sn-Ag/Cu and Sn-Ag-In/Cu samples at 240 °C were 0.35 ± 0.01 and 0.34 ± 0.02, respectively. The n values increased with reaction temperature, and it was higher for Sn-Ag/Cu than that for Sn-Ag-In/Cu sample at the same temperature. After Cu was exhausted, ε intermetallic compound was converted to η intermetallic compound. The mechanisms for such growth of interfacial intermetallic compounds during the liquid-solid reaction were investigated. [ABSTRACT FROM AUTHOR]

The phase stability, electronic structure, compressibility, optical and elastic properties of two polymorphs of Ti3SnC2 were investigated using first-principle calculation. α-Ti3SnC2 is confirmed to be the preferred equilibrium phase under high pressure and high temperature. The electronic structure calculations reveal that the Ti and C atoms form a strong Ti1-C-Ti2-C-Ti1 covalent bond chain while the bonding between Ti1 and Sn is relatively weak. In the low frequency range from radio waves to visible light, Ti3SnC2 behaves similarly with TiC. This material exhibits anisotropic compressibility under hydrostatic pressure: it is more compressible along the c-direction than along a-direction, related to the different bond stiffness and bond angle changes under high pressure. The second-order elastic coefficients were calculated. For the α-phase, the bulk, B, shear, G, and Young's moduli, E, are calculated to be 169.4, 124, and 197.4 GPa, respectively. The low G/ B ratio partially explains why Ti3SnC2 is relatively soft and damage tolerant. [ABSTRACT FROM AUTHOR]

In-situ sintering of the Ni-10 wt % Cr MCFC anode is attempted by adding an appropriate amount of Sn, one of those elements with a melting point lower than the operating temperature of an MCFC. The tape-cast green sheet is sintered for 100 h under the same condition as for an MCFC anode in operation and then characterized to determine whether or not it fulfilled the requirements for an MCFC anode. The porosity, pore size distribution, creep resistance and sinter resistance of the anode are judged to be adequate for an MCFC. [ABSTRACT FROM AUTHOR]

Impression creep testing of tin was performed in the temperature range of 343 K to 398 K and under a punching stress of 12 MPa to 55 MPa. During the impression test at constant load, a direct electric current in the range of 0 A to 6 A flowed through the punch into the sample, introducing an electromechanical interaction. Steady-state creep was observed under the simultaneous action of the electric current and mechanical stress. The steady-state impression velocity increased with increasing temperature, punching stress, and electric current. A hyperbolic sine relation was used to describe the stress dependence of the steady-state impression velocity for impression creep of tin. The apparent activation energy decreased with increasing electric current. [ABSTRACT FROM AUTHOR]