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The feasibility to produce hydrogen in the Sn-[H.sub.2]O/Sn[O.sub.2]-C thermochemical water splitting redox process depends mainly on the efficiency of the tin hydrolysis step, which has not been studied adequately so far, while the cassererite carboreduction is implemented by industry for tin production. The present work deals with the hydrolysis of different kinds of tin powders at different experimental conditions at moderate temperature range 180-620[degrees]C. In spite of the fact that the rate of hydrogen production is lower compared with other metals, e.g., zinc, at the same reactor temperature, high conversion level was obtained in a controllable reaction. Consequently, tin can be a relevant candidate for solar hydrogen production considering the advantage of significant lower temperatures required for the solar carboreduction of its oxide. [DOI: 10.1115/1.3090825] Keywords: hydrolysis, hydrogen production, thermochemical redox process, conversion

The design of internal-tin strands layout is developed and BrP strands are produced to have the parameters fully corresponding to the ITER Design Specifications. The fabricated strands BrP is heat treated to the conditions that are specified in the ITER technical requirements.

The study presents an experimental and theoretical investigation of the diffusion of Sn in internal-tin [Nb.sub.3]Sn through the interfilamentry matrix within a subelement. The results show that small amounts of Sn lead to a better high temperature conductivity.

A partial ambient argon pressure was employed for decelerating various species in the tin plume. The results indicated that the tins ions could be effectively mitigated with a partial argon pressure ~65 mTorr.

Investigating the rod-in-tube technique developed for the fabrication of Nb3Sn precursor wire for RHQ treatment is discussed. It is concluded that the addition of Bi seems not to negatively influence the superconducting the properties of Nb3Sn.

Dissolution of a planar intermetallic compound layer (Cu6Sn5) with concomitant scallop formation was observed. The dissolution growth process during reflow depends on the shape of the solder cap.

The synthesis of SnSe was systematically investigated in various alkaline media and at various temperatures with SnCl(sub 2).2H2) and selenium as source materials. The two chemical mechanisms for the formation of SnSe are presented and it is reported that the transmission electron microscopy results show a variation of crystal morphology of SnSe obtained in different media.

Single-crystalline samples of type-VIII clathrate [Ba.sub.8][Ga.sub.16-x][Al.sub.x][Sn.sub.30] are grown from Sn flux to analyze the structural and thermoelectric properties from 300 to 600 K. The Seebeck coefficients of all samples are largely negative and the large thermopower has coexisted with the metallic behavior in the electrical resistivity.

High quality electrical resistivity [rho](T) versus temperature data of as-prepared and [O.sub.2]-annealed [Cu.sub.0.5][Tl.sub.0.5][Ba.sub.2][Ca.sub.2][Cu.sub.3-y][Sn.sub.y][O.sub.10-[delta]] superconductors is analyzed for fluctuation-induced phenomena setting in at temperatures well above the critical temperatures. The critical temperature and the peak temperature are found to decrease with increased Sn substitution however these temperatures are improved to higher values after annealing the samples in oxygen atmosphere.

The effects of coating contents on the damping properties of the coated composites at various temperatures, frequencies and strain amplitudes are examined along with the microstructures of the coated composites. The results of damping characterization have shown that the damping capacities of the coated alumina borate whisker-reinforced-aluminum matrix composites have depended on the coating contents and strain amplitudes.

The advanced transmission electron microscopy technique is employed to explain the composition, as well as the structure and properties of different thermoelectric materials. The impact of nanostructuring and lattice strain on the photon transport taking place in the [NaPb.sub.18-x][Sn.sub.x][BiTe.sub.20] thermoelectric materials is also explained.

The effect of nanoparticle structure on gas sensing performance is examined and size-selected nanostructured Sn[O.sub.2] agglomerate particles for gas sensors are made by scalable flame spray pyrolysis. Sensor layers made with the size-fractioned agglomerates have displayed higher thermal stability and have enhanced sensitivity for both analytes than layers made with polydisperse agglomerates.

Two homologous and isostructural compounds [Na.sub.5][M.sub.2+x][Sn.sub.10-x] (M = Zn, Hg) are obtained by direct reaction of the elements at high temperature and the crystal structures of these phases are determined from single-crystal X-ray diffraction data. Rigid band analyses have shown that the electronic structure of the phases with the compositions have corresponded to heavily doped semiconductors, thus meeting an important requirement of thermoelectric materials.

Synthesis experiments at 10 GPa and 1500 K followed by annealing at 770 K using Ge and Sn starting materials and ex-situ analysis have documented the recovery of a [Ge.sub.0.9][Sn.sub.0.1] solid solution.

The transport characterization measurements were performed at temperatures 4.2

The refractive properties of the amorphous chalcogenide glass [Sn.sub.1][As.sub.20][S.sub.79] and the effect of annealing at temperatures below the glass transition temperature are examined. The [Sn.sub.1][As.sub.20][S.sub.79] strip waveguide is fabricated by using the photoinduced refractive index change and the device has functioned as expected with good propagation characteristics for the 632.8 nm guided mode.

The first direct measurement of the interfilament transverse resistance in superconducting strands from room temperature to 4.2 K is described. The results are compared to the transverse resistance of a sample on which the outer copper stabilization layer is removed by chemical etching.

Current-voltage (I-V) curves are measured on Zn nanowires in contact with bulk film electrodes of Sn or Pb, where the Zn nanowires have become superconducting at the transition temperature of the respectively electrodes. The results have shown that the proximity effect has occurred along the entire length of a nanowire, rather than only at the nanowire-electrode interfaces.

Magnetic measurements on the hydrogenated systems U(Co,Fe)Sn and (U,Th)CoSn are performed as part of examination of UTX compounds (T - transitional metal and X - p-metal). The crystal-structure type is not changed upon the hydrogenation, the Curie temperature [T.sub.C] has increased in the hydrides and this increment is reduced with increasing Fe concentration.

The temperature dependence of the structural parameters and the occurrence of magnetism in UPdSn and UCuSn are measured by using neutron diffraction. Rietveld refinement of neutron diffraction data is used for determining the shortest interatomic distances for temperatures between 15 K and room temperature and the changes in the interatomic distances have caused changes in the hybridization effects, leading to the formation of a magnetic ground state for both compounds.

X-ray diffraction and magnetization measurements are used for studying the effects of Ni substitution on the magnetic properties and magnetocaloric effect (MCE) of [([Mn.sub.1-x][Ni.sub.x]).sub.3][Sn.sub.2] (x = 0-0.5) compounds. The studies have shown that Ni substitution has decreased the crystal cell volume and the magnetic transition temperatures when compared with pure [Mn.sub.3][Sn.sub.2].

The role of chemical ordering and annealing in fine-tuning the magnetostructural properties of [Ni.sub.50][Mn.sub.50-x][Sn.sub.x] (x=10-25) is examined. The results have shown that the martensitic transformation has occurred only in those compositions where the single phase [L2.sub.1] is retained in a metastable state on cooling.

Subnanosecond laser pulse irradiation and thermoreflectance measurement are used for characterizing thermal diffusivity of polycrystalline tin-doped indium oxide (ITO) films. The Wiedemann-Franz law is used for estimating the thermal conductivity carried by free electrons and the phonon contribution to the heat transfer in ITO films with various resistivities is almost constant, which is about twice that for amorphous indium zinc oxide films.

The thermal and electronic transport properties on rare-earth dichalcogenide compounds of Ce[Te.sub..sub.2x] are examined by measuring electrical resistivity, thermal conductivity and Seebeck coefficient. The symmetric electron-hole band dispersion of Ce[Te.sub.2] is shown to be responsible for the low Seebeck coefficient.

Magnetization measurements are used for examining the effect of the Mn substitution by Fe atoms on the magnetocaloric and magnetic properties of the martensitic [Ni.sub.50][Mn.sub.36][Sn.sub.14] Heusler-type compound. The insertion of Fe atoms has reduced the Mn-Mn AF interactions resulting in a systematic decrease in the martensic transition temperature and an increase of the saturation magnetization.

The heat capacity of the [Mn.sub.3][Sn.sub.2] compound is measured in magnetic fields up to 7 T. The isothermal magnetic entropy change and the adiabatic temperature change are calculated and three transitions are detected in the zero-field heat capacity versus temperature curve.

The thermal cycling (T/C) reliability of Cu/SnAg double-bump flip chip assemblies is examined and the failure mechanism is analyzed through the correlation of T/C test and the finite element analysis (FEA) results. The accumulation of plastic strain is the major cause of thermal fatigue failure and the distribution of bumps for the plastic deformation in the FEA has corresponded well with the number of failed bumps during T/C test.

The different metallization schemes, namely, Ag, Al, In, and Sn to SnS films are examined to understand the crucial task of selection of Ohmic contacts for the fabrication of efficient SnS devices. All M/SnS structures, except Ag/SnS, showed excellent Ohmic behavior over the voltage range from -10 to 10 V at room temperature and their thermal stabilities are examined by annealing them at different temperatures.

The electronic structures and defect formation energies for a series of stannate pyrochlores [Ln.sub.2][Sn.sub.2][O.sub.7] (Ln = La, Pr, Nd, Sm, Gd, Tb, Ho, Er, Lu and Y) are examined by using the first-principles energy calculations. The results have shown that Ln-site cation ionic radius, lattice constant and the covalency of bond have a major impact on the defect formation energies.

The modified reverse-impact geometry is used in shock experiments to analyze the phase transitions of tin at high pressure. Shock-induced bct-bcc transition and melting of tin are identified based on the discontinuity of the longitudinal sound velocity against shock pressure and the shear modulus and yield strength at loaded shock stresses are extracted from the measured sound velocities.

The thermoelectric properties of air-prepared cosubstituted indium oxide based compounds belonging to the series [In.sub.2-2x][M.sub.x][Sn.sub.x][O.sub.3] are studied. The analysis has stressed the vital role of cosubstitution to improve the thermoelectric properties of these n-type oxides.

The second-order phase transition observed in [Sn.sub.2][P.sub.2][([Se.sub.0.05][S.sub.0.96]).sub.6] single crystal at the corresponding temperature and atmospheric pressure is reported. The [Sn.sub.2][P.sub.2][S.sub.6] monocrystals exhibiting high pyroelectric, piezoelectric, electrooptic, and other quantity criteria could find sensor applications in modern electronics in a wide temperature and pressure range.

A study was conducted to determine the possible application of half-Heusler alloys [Zr.sub.1-x][Ti.sub.x]Co[Sn.sub.y][Sb.sub.1-y] (0.0

A study was conducted to examine the electrical characteristics of indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT:PSS)/ITO devices. The results provide insight into the donorlike trap states within the PEDOT:PSS layer which controlled carrier flow and resulted in hysteresis-type I-V characteristics of ITO/PEDOT:PSS/ITO devices.

The reduction of dopant deactivation and enhancement in thermal stability of boron-supersaturated Si during post-laser-rapid-thermal-anneal through the incorporation of tin as a strain-compensating element is reported.

The interaction of a laser pulse with a preformed Sn plume is examined for an extreme ultraviolet (EUV) lithography light source. Laser absorption in the low-density preplume and ion acceleration during plasma expansion have provided a general way to control particle energy from a laser plasma interaction.

The evolution and dynamics of laser-generated Sn plasma is studied using optical emission spectroscopy. The spatial variation of density and the rise in time-integrated temperature at greater distances might be caused by the deviation from local thermodynamics equilibrium at larger distances from the target surfaces.

The overtone and combination bands of the fundamental vibration modes attributed to the H2O molecules adsorbed on a TiO2 surface could be observed in the near-infrared (NIR) region. The results reveal that H2O molecules absorbed on a TiO2 surface aggregate to form clusters due to the high surface tension of H2O arising from the intermolecular hydrogen bonds.

The thermoelectric properties of the stoichiometric and off-stoichiometric Heusler compounds Fe(sub 2-x)Ti(sub 1+x)Sn between 10 K and 400 K were studied. It was found that the electrical resistivity and Seebeck coefficient were sensitive to the off stoichiometric.

Thermal decomposition is used for the preparation of antimony and antimony-platinum doped tin dioxide electrodes supported on titanium. The performance of a morphological study of the deposited layers by scanning electron microscopy (SEM) is discussed.