The apparent diffusion coefficients of strontium in compacted bentonites were investigated at various concentrations of NaHCO3. Purified sodium bentonite Kunipia-F® was compacted with a jig into cylindrical pellets 10 mm in diameter and 10 mm high with dry densities of 1.0 to 1.6 Mg/m3. Each bentonite pellet was inserted into an acrylic resin column and saturated with carbonated water containing 0.1 to 1.0 M NaHCO3 for more than 1 month. The face of the bentonite specimen was spiked with 5 μL of 1.0 M SrCl2 tracer solution. After a few weeks, the strontium diffusion profiles were measured by inductively coupled plasma-mass spectrometry. The apparent diffusion coefficients of strontium decreased slightly with increasing dry density. NaHCO3 concentrations of 0.5 M decreased the apparent diffusion coefficients of strontium by half at a dry density of 1.0 Mg/m3 and quarter at 1.6 Mg/m3. At a higher NaHCO3 concentration of 1.0 M, no strontium diffusion profile was observed, whereas white precipitate was observed on the face of the bentonite specimen where it was spiked with strontium. This white precipitate could be strontianite, which is strontium carbonate. Diffusion experiments using cesium were carried out for comparison, and the presence of carbonate had no effect on the apparent diffusion coefficient.

The partitioning of Sr, Ba and Rb between alkali feldspar and melt has been determined at 0.1 GPa water vapour pressure, mainly on one Na-rich series and one K-rich series within the system nepheline-kalsilite-quartz. Experiments were also carried out with small amounts of the anorthite molecule or peralkaline components (Na, K metasilicates). The compositions of the alkali feldspars and coexisting quenched glasses were determined by electron microprobe analysis. Except for some peralkaline compositions, the crystal/liquid partition coefficients for Sr and Ba are always >1; the crystal/liquid partition coefficient for Rb is always <1. For sodic alkali feldspars DSr > DBa and for potassic feldspars DSr < DBa. Partition coefficients for Sr and Ba increase: (1) with decreasing temperature; (2) with increasing Or content of feldspar; (3) with increasing silica-undersaturation of the melt; (4) with decreasing peralkalinity. The variation in the value of DRb is less clear, but it is higher for K-rich feldspars. Multiple linear regression equations are fitted to correlate ln(D) with independent compositional and physical variables. Where rock/groundmass major-element data are available for felsic natural rocks, equations are recommended for obtaining reliable alkali feldspar partition coefficients for modelling fractional crystallization processes. The structural properties of silicate melts and crystal chemical relations are used to rationalize trends in partition coefficients.

Surface modification by the bioactive material is a potential way to overcome the poor osseoconductivity of titanium (Ti)-based implants. A continuous wave laser source was used to deposit strontium titanate (SrTiO3)-reinforced Ti coating on the Ti substrate using the laser engineered net shaping (LENS™) process. The maximum of 10 wt% SrTiO3 could be incorporated into Ti using laser without cracking of the deposit. This study investigated the constituent phases, microstructure, compositional analysis, wettability, and electrochemical behavior of the composite coatings. XRD and EDX analyses confirmed the presence of the SrTiO3 phase in the coatings. The composite coatings also exhibited superior mechanical properties, corrosion resistance, and bioactivity compared to that of commercially pure Ti. In vitro ion release study confirmed the sustain release of Sr2+ from the composite coatings. In summary, the excellent mechanical bonding with the substrate and high in vitro bioactivity make these SrTiO3-incorporated composite coatings as a potential material to enhance osseoconductivity of Ti-based orthopedic implants.

BaAl2Si2O8 and SrAl2Si2O8 were synthesized by solid-state reaction of stoichiometric mixtures of either BaCO3 or SrCO3 with coal fly ash and Al2O3. The mixtures were mechanically activated in an attrition mill for up to 12 h and then reaction-sintered at 900-1300 °C, aiming to promote the formation of BaAl2Si2O8 and SrAl2Si2O8 as well as the conversion from their hexagonal (Hexacelsian) into their monoclinic (Celsian) forms, which is associated with improved mechanical properties in the sintered materials. Especially in the case of SrAl2Si2O8, the formation of Celsian was favored at relatively low sintering temperatures by increasing milling time. Although only the SrAl2Si2O8 composition was fully converted into Celsian, the Hexacelsian to Celsian conversions obtained for the mechanically-activated BaAl2Si2O8 composition were significantly higher than those previously reported in the literature for this compound. This could be attributed to the use of coal fly ash as raw material, which contains mineralizers that promote the mentioned conversion.

In Japan, scallop shells are considered to be industrial waste. Thus far, attempts for reusing these shells have been mainly limited to the commercial production of CaCO3. Nevertheless, there are no clear economic benefits associated with the use of scallop shells as a source of CaCO3. Hence, we are attempting to investigate a new value-added use for scallop shells as an advanced functional material. In this regard, we focused our attention on nuclear wastewater, which contains radioactive Sr and Cs. Sr, which tends to accumulate in bones, is believed to cause bone cancer. Hence, it is highly desirable to develop a method for removing Sr from contaminated water. In this study, we investigate whether scallop shells demonstrate the ability to remove Sr from a solution. From the results obtained, scallop shells can remove Sr solutes from a solution; furthermore, as compared to CaCO3, they demonstrate superior ability for removing Sr.

This article offers a distinctively Anglican evaluation of the practice of Scriptural Reasoning. It draws upon personal experience, and frames its discussion with two ‘case studies’ describing SR study in action. It engages closely with Peter Ochs's positive theorization of Anglican postliberalism from a Jewish perspective in his book Another Reformation. With Ochs, the article rejects the premise that a neutral ‘common ground’ of theoretical agreement is a prerequisite for fruitful encounter across religious traditions, and claims that the traditions in question have generated their own tradition-specific resources for dialogue. The central part of the argument looks for correlations between an Anglican trinitarianism that valorizes historical process and analogical reasoning (something that, with Ochs, might be described as a pneumatological emphasis on the ‘found’), and an Anglican legitimation of SR. The value of reading commentary from the Christian, Jewish and Muslim traditions alongside scriptural texts is asserted.

The SrZnO2 thin films were fabricated by using laser ablation method. The films were annealed after deposition in order to improve the crystallinity. Water splitting experiments were carried out and hydrogen production over the SrZnO2 thin films were confirmed with no applied bias. The band gap of SrZnO2 was 3.41 eV which is 0.15 eV larger than that of ZnO. It suggests that the band gap was increased by doping Sr to ZnO, and the reducibility was improved. As a result, the rate of photocatalytic hydrogen production over the SrZnO2 was increased compared to ZnO.

We present a provenance study of core ZK2 from the Huanghe (Yellow River) Delta in order to assess the impacts of climate change on the sediment supplies during the last glacial–interglacial cycle. Facies analysis and sequence stratigraphy methods are used to construct the age model. Sr isotopic compositions of ZK2 range from 0.716389 to 0.723884, with 87Sr/86Sr increased with decreasing grain size. Nd and Pb isotopic compositions display two large major excursions during Marine Oxygen Isotope stages (MIS) 2 and 4, with less radiogenic εNd and lower 208Pb/204Pb, 207Pb/204Pb, and 206Pb/204Pb values during these periods. These excursions have been explained in terms of changes in the mixing proportion of sediments from the Loess Plateau and Ordos Plateau, resulting from East Asian monsoon intensity variations. The weak summer monsoon precipitation resulted in decreased erosion of Loess Plateau during MIS 2, 4 and the middle of MIS 3. Meanwhile, both the intensified East Asian winter monsoon and the southward expansions of Mu Us desert significantly enhanced the eolian sand entering the Huanghe. Therefore, our results highlight the impact of monsoon variability on erosion patterns in the Huanghe basin.

The anhydrous acid strontium oxalate Sr(HC2O4)⋅½(C2O4) was obtained by thermal decomposition of the hydrated acid strontium oxalate Sr(HC2O4)⋅½(C2O4)⋅H2O. This non-hygroscopic compound crystallizes in the space group P 21/c (No. 14) with unit cell parameters: a=0.796 61(7) nm, b=0.9205(1) nm, c=0.731 98(8) nm, and β=102.104(8)°. Final refinement of the X-ray powder data yielded RB=3.2% and Rwp=11.1% (background-corrected data). In this structure, Sr is eight-fold coordinated by O. These polyhedra are connected together by edge-sharing to form two-dimensional (2D) layers along the bc-plane, which means that there is an increased dimensionality from 1D to 2D with decreasing water content of the acid oxalates.

Water-splitting to form hydrogen was examined by using strontium titanate (SrTiO3) nanofibers as photocatalysts. SrTiO3 nanofibers were fabricated by hydrothermal treatment of amorphous titanium dioxide nanofibers, which were electrospun from the mixture of polyvinylpyrrolidone (PVP), titanium(IV) butoxide, and acetylacetone. The hydrothermal treatment involved the reaction of amorphous TiO2 nanofiber template with strontium hydroxide octahydrate (Sr(OH)2·8H2O) for 20 hours at 120 ºC. The product was calcined to form crystalline SrTiO3 nanofibers, which were characterized via Scanning Electron Microscopy (SEM)/Energy Dispersive Spectroscopy (EDS) and tested their photocatalytic activities for the water splitting. The hydrogen production with the fabricated SrTiO3 nanofibers was found to be 6.1 μmol·h-1·g-1 catalyst, which is twice that of commercially available SrTiO3 nanoparticles (3.0 μmol·h-1·g-1 catalyst).

Microstructural investigation and thermodynamic simulation were carried out to study precipitation during the solidification of AZ31 Mg alloy containing up to 1wt% Sr. Increasing Sr content from 0.01 to 1 wt% led to the formation of an Al–Sr line compound (Al4Sr) and to the suppression of Al–Mg precipitate (β-Mg17Al12). Transmission electron microscopic (TEM) investigation and energy dispersive spectroscopic analysis on extracted precipitates revealed Mg and Zn solubility in the Al4Sr particles. It is shown that Sr content also affects the precipitation of Al–Mn precipitates. Thermodynamic calculations predict that the increase in Sr content limits the Al–Mn reaction and the precipitation of Al–Mn precipitates with low Al/Mn ratio. Microstructural investigations determined the presence of two Al–Mn precipitates (Al8Mn5 and AlMn), either in the form of large dendritic plates or small nano-scale particles in the Mg matrix. It has been calculated by the thermodynamic model and confirmed by TEM that by increasing the Sr content, solubility of Al solid decreases whereas the level of Mn increases slightly.

Strontium titanium silicates are possible oxide forms for immobilization of short lived fission products in radioactive waste. Through beta decay, strontium decays to yttrium, and then to zirconium. Therefore, not only the stability of Sr-loaded waste forms, but also that of a potential decay product series with charge-balance in a naturally occurring mineral or a ceramic is of fundamental importance. Strontium titanosilicate (SrTiSiO5) is the Sr-analogue of titanite (CaTiSiO5). To incorporate the reaction 3Sr2+ = 2Y3+ + vacancy in the titanite composition, Y-substituted Sr-analogues of titanite, (Sr1–xY2/3x)TiSiO5 (x = 0, 0.25, 0.5, 0.75) were prepared by high temperature synthesis and were found to form glass upon cooling. The Y-end-member (Y2/3TiSiO5, x = 1) crystallized to a mixture of Y2TiSiO7, TiO2, and SiO2 upon quenching in air. The enthalpies of formation of Y-substituted Sr-titanite glasses were obtained from drop solution calorimetry in a molten lead borate (2PbO·B2O3) solvent at 702 °C. The enthalpies of formation from constituent oxides are exothermic but become less so with increasing Y content. The thermodynamic stability of the Y-substituted Sr-analogue of crystalline titanite may become marginal with increasing yttrium content.

Using a model cathode-electrolyte system composed of epitaxial thin-films of La1-xSrxMnO3-δ (LSM) on single crystal yttria-stabilized zirconia (YSZ), we investigated changes in the cation concentration profile in the LSM during heating and under applied potential using grazing incidence x-rays. Pulsed laser deposition (PLD) was used to grow epitaxial LSM(011) on YSZ(111). At room temperature, we find that Sr segregates to form Sr enriched nanoparticles and upon heating the sample to 700°C, Sr is slowly reincorporated into the film. We also find different amounts of Sr segregation as the X-ray beam is moved across the sample. The variation in the amount of Sr segregation is greater on the sample that has been subject to 72 hours of applied potential, suggesting that the electrochemistry plays a role in the Sr segregation.

The effects of Sr and B addition on the microstructure and mechanical properties of AZ91 alloy were studied. The results of this work show that a small amount of Sr addition to AZ91 refined the grain size. The highest tensile strength was obtained from the alloy with the optimal composition of 0.5% Sr and 0.09% B added, in which the average grain size was 42 μm. The tensile strength and elongation of the AZ91–0.5%Sr–0.09%B alloy were 151 MPa and 1.62%, respectively. Some needle-shaped Al4Sr particles distributed mainly at grain boundaries have been observed in the alloys with Sr and B additions. The fluidity is improved significantly, and the solidification range decreased by adding Sr and B. The liquidus of AZ91 alloy decreased markedly with the addition of Sr and B, but the solidus hardly changed. Therefore, the solidification range can be decreased, which will improve the die-casting properties.

Water samples (referred to as puddle water samples) were collected from the surfaces of a conveyor belt and plastic sheeting in the unventilated portion of the Enhanced Characterization of the Repository Block (ECRB) Cross Drift in 2003 and 2005 at Yucca Mountain, Nevada. The chemistry of these puddle water samples is very different than that of pore water samples from borehole cores in the same region of the Cross Drift or than seepage water samples collected from the Exploratory Studies Facility tunnel in 2005. The origin of the puddle water is condensation on surfaces of introduced materials and its chemistry is dominated by components of the introduced materials. Large CO2 concentrations may be indicative of localized chemical conditions induced by biologic activity.

Tantalate and titanate photocatalysts were prepared by solid-state reaction at 1273 K using various ratios of SrCO3, Ta2O5, and TiO2 as starting materials. The prepared solid photocatalysts were characterized using XRD and SEM analysis. These prepared tantalate and titanate photocatalysts showed high photocatalytic H2 evolution activity by water splitting without co-catalyst loading. The highest H2 evolution rate of prepared photocatalysts was found to be 138 μmolh−1 with the starting materials ratio of 2/0.5/1.5 (Sr/Ta/Ti; mol). Furthermore, this photocatalyst showed photocatalytic activity for H2 evolution from distilled water.

This paper reviews the petrogenesis of Himalayan leucogranites (HHγ) on the basis of field, petrological and geochemical data collected over the last fifteen years. HHγ are intruded at the top of the 2 to 8km-thick High Himalayan Crystallines (HHC). These are metamorphosed (Ky to Sill) and present much evidence of partial melting. During the MCT thrusting, the already metamorphosed HHC were thrust on top of the weakly metamorphosed Midland Formations, inducing the main phase of Himalayan metamorphism. The genesis of HHγ and North Himalaya leucogranites (NHγ) associates thrusting along the MCT, propagation of inverted metamorphism, liberation of large quantities of fluid in the Midlands, and partial melting of the HHC.

The restricted compositions of the granites are close to minimum melt compositions; variations in the alkali ratio probably relate to the variable amount of B, F and H2O. The HHγ were issued from the migmatitic zone around 700°C and 800 MPa., and still emplaced some 10 to 15 km below the surface. This syn- to late-tectonic emplacement of the leucogranites lasted for more than 10 Ma according to isotopic ages (25 to 14 Ma).

O, Rb–Sr, Nd–Sm and Pb isotope studies corroborate the unambiguous filiation between the HHC and the leucogranites in central Nepal. They also imply that the plutons are generated as numerous poorly mixed batches of magma produced preferentially in specific zones of the source rock. δD values may be explained by infiltration of water from the Midlands in the melting zone, and/or by water degassing during crystallisation. The positive covariations between Sr-, Nd- and O-isotope ratios relate to the variations in the original sediment composition of the source gneisses. Whereas trace element characteristics often date back to the anatectic process, limited magmatic differentiation is recorded by the biotite. These granites are typical crustal products, keeping track of some of the pre-Himalayan evolution together with that of their own origin.