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We evaluate three identifiers of continental mantle earthquakes (CMEs) motivated by surface‐wave normal‐mode theory: the amplitude ratio of Sn to Lg, and the frequency content of Sn and of Lg, after wave propagation through continental crustal thinning. These flexible and easily applicable methods allow for potential new discoveries of CMEs. They rely on guided waves whose propagation is dependent on the uniformity of their waveguides. For a range of Moho models, we perform 2.5D axisymmetric simulations that reach the conventional distance and frequency ranges of observational studies; we compare results from four different source depths straddling the Moho. Our synthetics, and six south‐Tibet earthquakes recorded by an array in Bangladesh, show our Sn/Lg identifier is robust in the presence of crustal thinning, but the identifying frequency contents of Sn and Lg are easily obscured. These results strengthen the utility of Sn/Lg methods for global studies of CMEs. Plain Language Summary: That continental mantle earthquakes (CMEs) occur is at last widely accepted, but the tectonic settings in which they occur remain conjectural. Systematic mapping of CMEs has been impossible because of the difficulty of distinguishing the depth of small earthquakes relative to the Moho, hence whether these earthquakes occur in crust or mantle. Our new method separates CMEs from conventional crustal earthquakes using amplitude and frequency ratios of early and late arriving waves known as Sn and Lg. The basic wave physics requires uniform waveguides for Sn (the curvature of the crust‐mantle boundary, i.e., the Moho) and for Lg (the crust), so changing waveguide shapes could influence these discriminants. Here we focus on the effect of crustal thinning. Our advanced computer simulations, and real data from earthquakes in South Tibet that cross the major crustal‐thinning Himalayan Moho ramp, demonstrate that the amplitude‐ratio metric is robust but frequency‐ratio metrics are less resilient. Our synthetic results deviate from a flat‐Moho model only due to crustal‐thinning, so we can isolate this effect, enabling our results to be quickly adaptable to other regions/applications utilizing Sn and Lg waves. Our guided‐wave‐based discriminants may permit a shift from reporting individual CMEs to mapping their world‐wide distribution. Key Points: Amplitude ratio of Sn and Lg is a robust discriminant for continental mantle earthquakes (CMEs) even across extreme crustal thinningFrequency content of Sn and Lg for CME discrimination is less robust than Sn/Lg amplitudes, with or without crustal thinningBy comparing nearby earthquakes recorded on the same stations, Sn/Lg may illuminate the as‐yet‐unknown world‐wide distribution of CMEs [ABSTRACT FROM AUTHOR]

Previous studies have primarily focused on promoting the (002) crystal plane of electrodeposited zinc (Zn) to grow thin Zn plates parallel to the electrode surface and thus achieving the dendrite‐suppressed Zn anodes. In contrast, this work adopts a novel approach. In situ construct a tin (Sn) modification layer on Zn foil. Through in‐depth cross‐sectional morphological analyses, the as‐designed Sn interface is observed to induce (101)‐preferred electrodeposition of Zn, leading to well‐ordered alignment of Zn thin plates “standing‐up” against the electrode surface at a universal angle of 65°. Such crystallographic characteristic consequently guarantees a flat and compact morphology of the electrochemically deposited Zn layer, thus suppressing the notorious problems of dendritic Zn growth and hydrogen generation. Consequently, the dendrite‐free Sn–Zn anode exhibits long‐term cycling stability of 4000 h at 1 mA cm−2 and 0.5 mAh cm−2, a significant improvement in comparison to the 50 h stability observed for unmodified Zn anode. The findings in this study offer a deep understanding of interface mechanisms and are instructive for innovative interface design for metal anodes. [ABSTRACT FROM AUTHOR]

Inhalation of nanosized metal oxides may occur at the workplace. Thus, information on potential hazardous effects is needed for risk assessment. We report an investigation of the genotoxic potential of different metal oxide nanomaterials. Acellular and intracellular reactive oxygen species (ROS) production were determined for all the studied nanomaterials. Moreover, mice were exposed by intratracheal instillation to copper oxide (CuO) at 2, 6, and 12 μg/mouse, tin oxide (SnO2) at 54 and 162 μg/mouse, aluminum oxide (Al2O3) at 18 and 54 μg/mouse, zinc oxide (ZnO) at 0.7 and 2 μg/mouse, titanium dioxide (TiO2) and the benchmark carbon black at 162 μg/mouse. The doses were selected based on pilot studies. Post‐exposure time points were 1 or 28 days. Genotoxicity, assessed as DNA strand breaks by the comet assay, was measured in lung and liver tissue. The acellular and intracellular ROS measurements were fairly consistent. The CuO and the carbon black bench mark particle were potent ROS generators in both assays, followed by TiO2. Al2O3, ZnO, and SnO2 generated low levels of ROS. We detected no increased genotoxicity in this study using occupationally relevant dose levels of metal oxide nanomaterials after pulmonary exposure in mice, except for a slight increase in DNA damage in liver tissue at the highest dose of CuO. The present data add to the body of evidence for risk assessment of these metal oxides. [ABSTRACT FROM AUTHOR]

Porous Sn (PSn) has aroused extensive attention as an advanced anode for sodium‐ion batteries due to its high theoretical capacity and small volume expansion. However, as a low‐melt metal, the preparation of PSn at room temperature is a difficult problem. Herein, universal chemical prelithiation/presodiation strategies are reported to rapidly synthesize PSn from commercial Sn powders at ambient temperature. The recyclable pre‐metallation solvents are selected by redox potential analysis to react with Sn to form alloy precursors in a short time. Benefiting from the application of delithiation/desodiation agents with suitable proton concentrations, PSn perfectly inherits the Sn skeleton from precursors. With this method, porous Al, Pb, Bi, and Sb are successfully produced. Finally, the half‐cell with PSn anode prepared by presodiation strategy achieves a great rate property (663 mAh g−1 at 10 A g−1) and prominent cycling performance with 71% capacity retention after 7500 cycles (502 mAh g−1) at 5 A g−1. This work may contribute to the controllable synthesis of other porous metals at room temperature. [ABSTRACT FROM AUTHOR]

Inverters play a prominent role in the power train system of electric vehicles (EVs). Devices in EV connected power system are threatened by faults due to the continuous working and varying speed range of motors in EVs. Hence, in the EV connected application, the detection of fault is essential since it secures the system from severe damage and dangerous operating conditions. This paper deals with fault detection in inverter‐fed EV using a dual‐tree complex wavelet transform (DTCWT) based squeeze net (SN) and optimized support vector machine (SVM). Due to the simple structure and high power density, most EV models on the market are equipped with induction motors. In the proposed work, the voltage, current, and speed signals are measured at different faulty conditions, and then the features are extracted through the DTCWT‐based SN. Extracted data are processed and classified through the sucker‐vulture optimization algorithm (SVOA) based SVM. In the proposed SVOA, the exploration phase of remora optimization algorithm is used for the exploitation phase of African vulture optimization algorithm (AVOA). Thus, the convergence speed of AVOA is improved. The proposed method is implemented in MATLAB/SIMULINK, and the results are used for different scenarios. The accuracy and F1‐score for the proposed methodology are attained as 99.92441% and 99.92441%. From the obtained results, it is clear that the proposed DTCWT‐based SN effectively detects the faults in the inverter. [ABSTRACT FROM AUTHOR]

As a metal functional material, the Mn–Cu‐based alloys are regarded to be able to cope with the vibration and noise from machines. In particular, the as‐cast alloys often exhibit an excellent damping capacity, which is attributed to the Mn segregation in the alloys. Herein, to amplify the kind of segregation, a trace of Sn is added in as‐cast Mn–Cu–Al alloys. The phase structures of the as‐cast Mn–44Cu–1.5Al alloys are analyzed in detail through X‐Ray diffraction (XRD). The distribution characteristics of face‐centered cubic (FCC) phases and face‐centered tetragonal (FCT) phases are observed using electron backscatter diffraction (BSE). The alloys' dynamic mechanical spectra and internal friction (IF) are measured using an inverted torsion pendulum device. It is found that the addition of Sn promotes the Mn segregation in the as‐cast Mn–44Cu–1.5Al alloys. A large amount of FCT phases appears in the dendritic trunks, enhancing the damping capacity of the alloys. In the meantime, the Sn atoms enhance the twin boundary mobility in Mn‐rich dendritic trunks. As a result, the alloy containing 1 wt% Sn has the highest damping capacity in the alloys. [ABSTRACT FROM AUTHOR]

The applications of alloy‐type anode materials for Na‐ion batteries are always obstructed by enormous volume variation upon cycles. Here, K+ ions are introduced as an electrolyte additive to improve the electrochemical performance via electrostatic shielding, using Sn microparticles (μ‐Sn) as a model. Theoretical calculations and experimental results indicate that K+ ions are not incorporated in the electrode, but accumulate on some sites. This accumulation slows down the local sodiation at the "hot spots", promotes the uniform sodiation and enhances the electrode stability. Therefore, the electrode maintains a high specific capacity of 565 mAh g−1 after 3000 cycles at 2 A g−1, much better than the case without K+. The electrode also remains an areal capacity of ≈3.5 mAh cm−2 after 100 cycles. This method does not involve time‐consuming preparation, sophisticated instruments and expensive reagents, exhibiting the promising potential for other anode materials. [ABSTRACT FROM AUTHOR]

As an anode material of lithium‐ion batteries (LIB), Sn has great application potential due to its high theoretical specific capacity. However, the Li–Sn alloying reaction causes serious volume expansion and destroys the electrode structure, resulting in a rapid capacity decay. Herein, a simple preparation method for the Sn–carbon composites (Sn/CF) is designed by electrodepositing Sn nanoparticles on 3D carbon foam (CF) derived from the carbonization of melamine. Sn/CF‐3h exhibits excellent electrochemical properties. At 1 A g−1, the specific capacity of Sn/CF‐3h remains 166.6 mAh g−1 with a high capacity retention of 85.4% even over 2000 cycles. The designed structure of the Sn/CF electrode contributes to its excellent performance: providing a 3D conductive network, accommodating volume changes to prevent Sn nanoparticles from losing electrical contact, and promoting contact with electrolyte to accelerate lithium ion transmission. [ABSTRACT FROM AUTHOR]

In this work, using the M06‐2X method with Land2DZ for Sn and Pb atom and 6‐311++G(d,p) for the remaining atoms, the reaction mechanisms and products of Sn and Pb with methanol in sludge incineration were investigated. Result shows that Sn and Pb react with CH3OH via insertion mechanism into different chemical bond, that is, CH, CO, and OH bond. The order of stability of final products is CH3MOH > CH3OMH > HMCH2OH (M = Sn and Pb) from the most stable to the least stable. Moreover, the reactivity of Sn towards methanol is higher than that of Pb via the same insertion chemical bond. Kinetically, the order of barrier height via insertion into different chemical bond is CO > OH > CH bond from highest to lowest, which is contrast to the stability of products. Thermodynamics indicates that all products are spontaneous to be formed below 1500 K in incinerator. It is therefore Sn‐ and Pb‐contained organic compounds would be generated readily in incineration of sludge. The secondary treatment of bottom slag or fly ash is expected to reduce the pollution to environment after incineration of Sn‐ and Pb‐contained sludge. [ABSTRACT FROM AUTHOR]

Summary: In the present study, nanorods of TiO2, Sn‐doped TiO2 (Sn‐TiO2), TiO2@Sn‐TiO2 and Sn‐TiO2@TiO2 were prepared by sol‐gel method. Dye‐sensitized solar cells (DSSCs) photoanodes were synthesized by depositing films on fluorine doped tin oxide (FTO) glass substrate using doctor blade method. The samples were characterized by scanning electron microscopy (SEM), X‐ray diffraction analysis (XRD) and UV‐Vis spectroscopy. XRD results indicated the formation of tetragonal anatase structure of TiO2 in pristine TiO2 and Sn‐TiO2 films. It was observed that formation of heterostructure particles spured the conversion of TiO2 from anatase to rutile phase. SEM analysis indicated the formation heterostructures of rod like morphology with increased diameter. Optical parameters of films (absorbance, transmittance, refractive index, dielectric constants and band gap) were measured using UV‐Vis spectroscopy data. The results confirmed that Sn doping decrease the bandgap. Amongst the four prepared films, band gap of Sn‐TiO2@TiO2 heterosturcture based film was smallest (3.09 eV). The efficiency of Sn‐TiO2@TiO2 heterostructure based DSSC was found to be 54.3% better compared with DSSC based on Sn‐TiO2 and 96.37% better compared with the DSSC based on pristine TiO2. [ABSTRACT FROM AUTHOR]

Organic‐inorganic halide perovskite solar cells (PSCs) have drawn tremendous attention as their power conversion efficiency (PCE) has soared to 25.2%. Yet the most efficient halide perovskite materials all contain the toxic element lead (Pb). The search for an alternative element is a crucial research direction. Among all candidates, tin (Sn) appears to be the most promising one for its nontoxicity and physical similarity to lead (Pb). Herein, we review and summarize recent advancements in this emerging research area of Sn‐based perovskites. First, we discuss the photophysical dynamics of the Sn‐based perovskites and the relatively high efficiency of corresponding PSCs and other applications. Then, the attention is focused on the fabrication process and methods to improve the performance of Sn‐based photovoltaic devices. Despite the fact that the stabilities of the materials and related devices are far from perfect, the Sn‐based perovskites are still the best candidates with vast potential among all the Pb‐free perovskites for PSC application. [ABSTRACT FROM AUTHOR]

A plum pudding‐like Sn‐based electrocatalyst is synthesized by calcinating the precursor SnC2O4 on carbon black (CB) with polymeric carbon nitride (CN). This material exhibits a structure of a Sn metallic ball coated with a nitrogen‐doped SnOx native layer (N‐doped SnOx@Sn) embedded on a carbon matrix. The carbon matrix originates from the CB and the polymeric CN decomposition promotes electrical conductivity, leading to high electrochemical activity of the CN–Sn catalyst. The introduction of nitrogen that occupies the interstitial space of the surface SnOx layer further enhances electron transport; furthermore, it provides an electron‐rich environment for oxygen because of its lower electronegativity, which is the fundamental cause of selectivity in the electrochemical reduction of CO2 to CO. The maximum CO Faradaic efficiency over the optimal catalyst reaches 57.5%, with a high CO partial current density of 6.09 mA cm−2 at −0.7 V versus reversible hydrogen electrode. This catalyst is further applied to construct a photovoltaic–electrocatalytic CO2 reduction/oxygen evolution reaction device to stably convert CO2 to chemicals over 6 h at a high solar‐to‐fuel efficiency of 11.3%. This work explores a strategy of rational modulation on surface electronic structure to obtain high‐performance electrocatalysts, inspiring the selectivity tuning in electrochemical CO2 reduction via electronegativity difference of various elements. [ABSTRACT FROM AUTHOR]

In this study a PdSn based sensor was developed for the determination of benzoic acid (BA) in foods. A carbon (Vulcan XC‐72R) supported PdSn catalyst was prepared via polyol method and its surface electronic and chemical properties were investigated by advanced surface analytical techniques such as scanning electron microscopy (SEM), X‐ray diffraction spectroscopy (XRD), X‐ray Photoelectron Spectroscopy (XPS), temperature‐programmed reduction with H2 (TPR‐H2) and transmission electron microscopy (TEM). Electrochemical measurements were performed by employing cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques on PdSn/GCE/Vulcan XC‐72R electrode. The developed sensor showed a wide linear range up to 10 mM with a 0.77 μM low limit of detection (LOD) as well as high stability. Further experiments were performed on food samples containing BA to achieve real sample measurements. For real sample measurements, PdSn/GCE/Vulcan XC‐72R electrode was used for the determination of BA in different kinds of samples such as mayonnaise, ketchup and carbonated beverages. [ABSTRACT FROM AUTHOR]

Sodium ion batteries (SIBs) have been regarded as a prime candidate for large-scale energy storage, and developing high performance anode materials is one of the main challenges for advanced SIBs. Novel structured Sn-MoS2-C@C microspheres, in which Sn nanoparticles are evenly embedded in MoS2 nanosheets and a thin carbon film is homogenously engineered over the microspheres, have been fabricated by the hydrothermal method. The Sn-MoS2-C@C microspheres demonstrate an excellent Na-storage performance as an anode of SIBs and deliver a high reversible charge capacity (580.3 mAh g−1 at 0.05 Ag−1) and rate capacity (580.3, 373, 326, 285.2, and 181.9 mAh g−1at 0.05, 0.5, 1, 2, and 5 Ag−1, respectively). A high charge specific capacity of 245 mAh g−1 can still be achieved after 2750 cycles at 2 Ag−1, indicating an outstanding cycling performance. The high capacity and long-term stability make Sn-MoS2-C@C composite a very promising anode material for SIBs. [ABSTRACT FROM AUTHOR]

The influence of Sn on pitting corrosion of ferritic stainless steels has been investigated by AC and DC electrochemical methods in 3.5 wt% NaCl and gravimetric tests in 6 wt% FeCl3 at 25 °C. 0.14 wt% Sn addition can improve pitting potential, while excessive addition (about 0.33 wt%) can deteriorate pitting corrosion resistance. Sn-bearing steels have higher passive film resistance and faster growth rate of more compact passive film, in which the charge carrier density is reduced probably due to the presence of SnO2. Dissolved Sn2+ can inhibit elementary anodic reactions. Therefore, the content of Sn should be optimized within 0.1-0.23 wt% to obtain better corrosion resistance. [ABSTRACT FROM AUTHOR]

Sn nanoparticles confined in amorphous carbon nanotubes (aCNTs) are synthesized via a nanowire‐directed templating method. Benefitting from the uniform distribution of the nanosized Sn particles and the robust aCNT framework, the Sn@aCNT hybrid structure shows excellent long‐term cyclability and high‐rate performance as an anode material for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

In this work we have observed a remarkable improvement in the thermoelectric (TE) performance of In6- xSn xSe7 ( ZT = ∼0.28 at x = 0.1, 833 K) compared to that of pristine In6Se7 ( ZT = 0.015 at 640 K). This improvement is mainly attributed to the creation of active donor defects SnIn3+ as Sn(4+) is energetically favorable to In+ sites. Although Sn (2+), which generates a defect SnIn− as an acceptor when it is incorporated into the In3+ sites, has a negative effect on the transport properties, the counter effect from Sn(4+) and Sn(2+) suggests that In6Se7-based alloys are prospectively good thermoelectric candidates if their chemical compositions are well optimized. [ABSTRACT FROM AUTHOR]

We have reported that the transistors having the c-axis-aligned crystalline (CAAC) In-Ga-Zn oxide (IGZO) show good performance. Recently, In-Sn-Zn Oxide (ITZO) has attracted much attention because of its high electron mobility, as well as IGZO. However, it has been reported that ITZO field effect transistors (FET) tend to have positive Vth (normally-on characteristics) and poor reliability compared with IGZO-FETs. We have reported that high-performance and high-reliability OS-FETs can be fabricated by using CAAC-IGZO, which has high crystallinity and has no clear grain boundaries, as an active layer. Therefore, we have fabricated CAAC-ITZO thin films to improve performance of ITZO-FETs by using CAAC-ITZO as an active layer. In addition, FETs employing CAAC-ITZO have better characteristics and reliability than FETs using nano-crystal ITZO. Furthermore, constant photocurrent method (CPM) measurement was carried out in order to estimate density of deep-level defect states caused by oxygen vacancies in oxide semiconductors. The results show that CAAC-ITZO has lower density of deep-level defect states than nano-crystal ITZO. We attribute the improvement in reliability of ITZO-FETs to a decrease in deep-level defect states of an ITZO active layer, as is the case with IGZO. [ABSTRACT FROM AUTHOR]

In this paper, we describe selective deposition of a major electrode and a protection electrode in a heterojunction with intrinsic thin-layer (HIT) type solar cell. Sn and Ni were used for the protection electrode to prevent the oxidation of Cu, which was used for the main electrode. SEM and TEM were used to analyze the microstructural evolution and changes in the interface as a result of each electroless deposition. Finally, the performance of our solar cell created via electroless deposition was evaluated. We determined the photovoltaic conversion efficiency ( PCE) to be 16.4 %, the fill factor ( FF) to be 72.2 %, the open circuit voltage ( Voc) to be 681 mV, and the short circuit current ( Jsc) to be 33.0 mA/cm2. These output values match the performance of an Ag screen-printed solar cell and demonstrate the possibility of commercializing an inexpensive HIT solar cell with high efficiency. [ABSTRACT FROM AUTHOR]

Granitic rocks obtained during field excursions of the famed mineralized regions of the Erzgebirge, Germany (mainly tin-bearing), and South China (mainly tungsten-bearing) have been geochemically analyzed and their results are compared with similar (mainly tungsten-bearing) granites in the island-arc setting of Southwest Japan. The studied granitoids all belong to the ilmenite-series. The collision-related Erzgebirge granitoids are rich in K2O and P2O5, have high A/CNK ratios (1.11-1.24, i.e. S type), but are also high in Ga/ Al ratio (i.e., having some A-type characteristics). In South China, the Xihuashan granites, in contrast, are very low in P2O5, and have A/CNK slightly above 1.0 (1.01-1.05), indicative of I type granites. The ( Sn-) W-related granites of southwest Japan have similarly low P2O5 and A/CNK ratios, indicative also of I-type. Both in the Xihuashan and southwest Japan, the tungsten-related granites have high whole-rock δ18O values implying involvement of W-rich crustal rocks. Sn and W contents of the unaltered granites are lowest in the island-arc setting where the related Sn- W deposits are smallest in size relative to the collision and continental margin settings of the Erzgebirge and South China. [ABSTRACT FROM AUTHOR]

Sn is regarded as a promising anode material for Li-ion batteries due to high capacity and cost effectiveness. Hitherto large-scale fabrication of Sn-based materials while achieving both high capacity and long cycle life remains challenging, but it is highly required for its realization in practical applications. Furthermore, low melting point always casts shadow over the morphology-controllable preparation, and leads to multistep or high-cost processes. Here, a facile and scalable method is devised for a 2D hybrid structure of Sn@graphene-based nanosheets incorporating of optimized nitrogen species (≈13 wt%). Distinct from conventional Sn-C composites, the fairly N-rich carbon nanosheets liberate limited potential of low N doping, induce massive extra Li-storage sites, and encourage a high capacity significantly. In addition, these abundantly anchored heteroatoms also promote the homogeneous dispersion and robust confinement of ultrasmall Sn nanoparticles into the flexible graphene-based nanosheets. This elastic encapsulation towards Sn nanoparticles admirably maintains structural integrity through effective remission of volume expansion, demonstrating a super long-term cyclic stability for 1000 cycles. This structural and componential engineering offers a significant implication for rational design of materials in extended areas of energy conversion and storage. [ABSTRACT FROM AUTHOR]

Zn1− xSn xO thin films were deposited on K9 glass and Si substrates by co-sputtering Zn and Sn targets under atmospheres of Ar and O2. The samples were then characterized with X-ray diffraction (XRD), Raman, energy-dispersive X-ray spectroscopy (EDX), Seebeck effect, four-probe instrument, and UV/VIS spectrophotometry. XRD and Raman show that all the samples are hexagonal and Sn doping increases the stress greatly. EDX demonstrates that the atomic ratio of Sn to Sn plus Zn is 0.04-0.07. All the samples are n-type. The resistivity of Zn1− xSn xO is much smaller than that of undoped ZnO deposited under the same conditions. The optical bandgap of Zn1− xSn xO is also reduced compared with that of ZnO deposited under the same conditions. [ABSTRACT FROM AUTHOR]

Geofluids (2010) 10, 41–57 Complexation by ligands in hydrothermal brines is a fundamental step in the transport of metals in the Earth's crust and the formation of ore deposits. Thermodynamic models of mineral solubility require an understanding of metal complexation as a function of pressure, temperature and composition. Over the past 40 years, mineral solubilities and complexation equilibria under hydrothermal conditions have been predicted by extrapolating thermodynamic quantities using equations of state based on the Born model of solvation. However, advances in theoretical algorithms and computational facilities mean that we can now explore hydrothermal fluids at the molecular level. Molecular or atomistic models of hydrothermal fluids avoid the approximations of the Born model and are necessary for any reliable prediction of metal complexation. First principles (quantum mechanical) calculations based on density functional theory can be easily used to predict the structures and relative energies of metal complexes in the ideal gas phase. However, calculations of metal complexation in condensed fluids as a function of temperature and pressure require sampling the configuration degrees of freedom using molecular dynamics (MD). Simulations of dilute solutions require very large systems (thousands of atoms) and very long simulation times; such calculations are only practical by treating the interatomic interactions using classical two- or three-body interatomic potentials. Although such calculations provide some fundamental insights into the nature of crustal fluids, simple two- or three-body classical potentials appear to be inadequate for reliably predicting metal complexation, especially in covalent systems such as Sn2+, Au3+ and Cu+. Ab initio MD (i.e. where the bonding is treated quantum mechanically, but the molecular motions are treated classically) avoids the use of interatomic potentials. These calculations are practical for systems with hundreds of atoms over short times (<10 psec) but enable us to predict complexation as a function of pressure, temperature and composition. In this paper, I provide an introductory outline of the computational methods and illustrations of their application to NaCl brines and the complexation of Cu, Au, Sn and Zn. [ABSTRACT FROM AUTHOR]

Dopaminergic neurons of the substantia nigra constitutively express the CXCR4 receptor for the chemokine stromal-cell-derived factor 1α (CXCL12) but, to date, no direct effect of CXCR4 activation by CXCL12 on membrane conductance of dopaminergic neurons has been demonstrated. We tested the effects of CXCL12 on whole-cell currents of dopaminergic neurons recorded in patch clamp in substantia nigra slices and showed that CXCL12 (0.01–10 nm) increased the amplitude of total high-voltage-activated (HVA) Ca currents through CXCR4 activation. This effect was reversibly reduced by ϖ-conotoxin-GVIA, suggesting that CXCL12 acted on N-type Ca currents, known to be involved in dopamine (DA) release. We therefore investigated the effects of CXCL12 on DA release from cultured dopaminergic neurons from the rat mesencephalon. In basal conditions, CXCL12 alone had no effect on DA release. When neurons were depolarized with KCl (20 mm), and thus when HVA Ca currents were activated, low CXCL12 concentrations (1–50 nm) increased DA release via CXCR4 stimulation. These data strongly suggest that the chemokine CXCL12 can act directly as a neuromodulator of dopaminergic neuronal electrical activity through the modulation of HVA currents. [ABSTRACT FROM AUTHOR]

While extracellular dopamine (DA) concentrations are increased by a wide category of salient stimuli, there is evidence to suggest that DA responses to primary and conditioned rewards may be distinct from those elicited by other types of salient events. A reward-specific mode of neuronal responding would be necessary if DA acts to strengthen behavioral response tendencies under particular environmental conditions or to set current environmental inputs as goals that direct approach responses. As described in this review, DA critically mediates both the acquisition and expression of learned behaviors during early stages of training, however, during later stages, at least some forms of learned behavior become independent of (or less dependent upon) DA transmission for their expression. [ABSTRACT FROM AUTHOR]

The design and performance results for a cryogenically stabilized high-resolution monochromator for 23.880 keV (λ = 52 pm) X-rays are presented. The four-crystal-reflection monochromator is suitable for nuclear resonant scattering measurements from 119Sn compounds using synchrotron radiation. The design includes a low-vibration cryostat that maintains two of the four crystal reflections at a temperature where the coefficient for thermal expansion of the crystalline material (silicon) vanishes. Test results demonstrate a 1.3 meV bandwidth with negligible broadening due to vibrations and a spectral efficiency of 37% when used with an undulator source. [ABSTRACT FROM AUTHOR]

In this work ab initio molecular orbital methods were employed to study the coal combustion reaction mechanisms of tin oxidized by different oxidants, including HOCl, HCl, ClO, ClO2, NO3, CO2, and O2. Eleven reaction pathways were identified. The results show that Sn can react with HCl, ClOO, CO2, O2, and NO3 to form SnO and SnCl. SnO can be oxidized into SnCl by HOCl and HCl. SnCl can be further oxidized into a soluble compound, SnCl2. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [ABSTRACT FROM AUTHOR]

Pb2BiS2I3 (I), Sn2BiS2I3 (II), and Sn2BiSI5 (III) are prepared by solid state reaction of stoichiometric amounts of PbS and BiI3 for (I) (silica tube, 500 °C, 72 h; ≈90% yield) and from a 2:1:2:3.15 molar mixture of Sn, Bi, S, and I2 for mainly (II) and minor amounts of (III) (evacuated silica tubes, 500 °C, 24 h). [ABSTRACT FROM AUTHOR]

Nanoplatelets of the title compound are prepared by hydrothermal reaction of an aqueous NaOH solution of SnCl2 (pH 13, autoclave, 180 °C, 16 h). [ABSTRACT FROM AUTHOR]

A series of indolyl substituted 1,4,6,7-tetrahydropyrano[4,3-c]pyrazole derivatives is synthesized via a domino method based on 1,4:6,7-dianhydrofructose. [ABSTRACT FROM AUTHOR]

Multifunctional phosphors Zn3Ga2SnO6:Cr3+, Nd3+, Gd3+ with near-IR long persistent phosphorescence, photothermal response, and magnetism are prepared by solid state reaction of stoichiometric amounts of ZnO, Ga2O3, SnO2, Cr2O3, Gd2O3, and Nd2O3 (1350 °C, 4 h). [ABSTRACT FROM AUTHOR]

Review: 268 refs. [ABSTRACT FROM AUTHOR]

Crystals of [K([2.2.2]crypt)]4 [CuSn5Sb3]2·3en (I) and [K([2.2.2]crypt)]4 [CuSn5Sb3]2·2toluene (II) are obtained in the reaction of equimolar amounts [K([2.2.2]crypt)]2[Sn2Sb2]·en (III) and the β-diketiminato complex [LCu(MeCN)] (L: [(N(C6H3iPr2-2,6)C(Me))2CH] -) in en or DMF (3 h; layering with toluene, 5 °C, 10-14 d). [ABSTRACT FROM AUTHOR]

An automated and exhaustive symmetry-mode method is presented for systematically exploring and solving symmetry-lowering structural phase transitions that is widely applicable to a range of functional materials. [ABSTRACT FROM AUTHOR]

Narrowly disperse rhombohedral Sn4P3 (I), hexagonal SnP (II), and trigonal Sn3P4 (III) nanoparticles (NPs) are prepared by size-, shape-, and phase-controlled colloidal synthesis. [ABSTRACT FROM AUTHOR]

Cu2ZnSnS4 (CZTS) thin films are prepared by spin coating of a precursor solution on Mo-coated glass substrates. [ABSTRACT FROM AUTHOR]

The title compound is synthesized by ball-milling of powder mixtures of Cu, Zn, Sn, and Te (planetary ball mill, 450 rpm, 30 h). [ABSTRACT FROM AUTHOR]

Polycrystalline BaCu2SnSexS4-x (x = 0, 1, 2, 3, 4) samples are prepared by solid state reaction of stoichiometric amounts of BaS, SnS, CuS, BaSe, SnSe, and CuSe (evacuated quartz tubes, 650 °C10-15 h). [ABSTRACT FROM AUTHOR]

Review: 86 refs. [ABSTRACT FROM AUTHOR]

K5Sb5P2O20 (I) is prepared by solid state reaction of stoichiometric amounts of KNO3, Sb2O3, and (NH4)2HPO4 (1. [ABSTRACT FROM AUTHOR]

Bulk Cu2Sn1-xInxSe3 (x = 0-0.2) samples are prepared by high-pressure combustion synthesis (HPCS) of stoichiometric amounts of the elements under 2 MPa Ar in a quartz tube. [ABSTRACT FROM AUTHOR]

[H3O]3[Heta]4.2 [H2dpp]0.3 [In4Sn16O10S32] ·33H2O is prepared by heating a 10:3:3:3 molar mixture of S, SnCl2·2H2O, In(NO3)3, and 1,3-di(4-pyridyl)propane (dpp) in ethanolamine (eta) (autoclave, 160 °C, 7 d; 25% yield). [ABSTRACT FROM AUTHOR]

Black sheet-like crystals of the title compound are prepared from mixtures of Sn, Se, AgCl, NH2NH2·H2O, 4-(4-(dimethylamino)styryl)-1-methylpyridinium iodide, and sodium p-toluenesulfonate (autoclave, 160 °C, 5-7 d). [ABSTRACT FROM AUTHOR]

Impedance measurements indicate high ionic conductivity of the layered compound K0.72Na0.24Sn0.76O2. [ABSTRACT FROM AUTHOR]

Single crystals of the title compounds are prepared from the elements (graphite crucible, 500-700 °C, 90 h). [ABSTRACT FROM AUTHOR]

Single-phase orthorhombic SnSe nanoplates are fabricated in gram quantities by boiling a black precipitate formed by combining aqueous solutions of NaHSe and Na2SnO2 (2 h, 94% yield). [ABSTRACT FROM AUTHOR]

Review: 293 refs. [ABSTRACT FROM AUTHOR]

Single crystals of Ce3Pt4Sn6 (I) and Ce1-xPt6Al13+2x (x = 0.207, (II)) are isolated by mechanical fragmentation of specimens grown from self-fluxes (Sn or Al, resp.) by slow cooling from the melt. [ABSTRACT FROM AUTHOR]

The title compounds are prepared from the elements (alumina crucible, 600-650 °C, 10 d). [ABSTRACT FROM AUTHOR]

Two new compounds, Ni3+xSn4Zn (x≈1.35, monoclinic, space group I2/m, Z = 2, single crystal XRD) and Ni6+xSn8Zn (x≈1.35, monoclinic, space group C2/m, Z = 2) are prepared by solid state reaction of the elements (Al2O3 crucible in evacuated quartz tubes, 1453 K). [ABSTRACT FROM AUTHOR]