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Equilibria between Ti oxides and silicate melt lead to Ti isotope fractionation in terrestrial samples, with isotopically light Ti oxides and isotopically heavy coexisting melt. However, while Ti is mostly tetravalent in terrestrial samples, around 10% of the overall Ti is trivalent at fO2 relevant to lunar magmatism (~ IW-1). The different valences of Ti in lunar samples, could additionally influence Ti stable isotope fractionation during petrogenesis of lunar basalts to an unknown extent. We performed an experimental approach using gas mixing furnaces to investigate the effect of Ti oxide formation at different fO2 on Ti stable isotope fractionation during mare basalt petrogenesis. Two identical bulk compositions were equilibrated simultaneously during each experiment to guarantee comparability. One experiment was investigated with the EPMA to characterize the petrology of experimental run products, whereas the second experiment was crushed, and fabricated phases (i.e., oxides, silicates and glass) were handpicked, separated and digested. An aliquot of each sample was mixed with a Ti double-spike, before Ti was separated from matrix and interfering elements using a modified HFSE chemistry. Our study shows fO2-dependent fractionation within seven samples from air to IW-1, especially ∆49Tiarmalcolite-melt and ∆49Tiarmalcolite-orthopyroxene become more fractionated from oxidized to reduced conditions (− 0.092 ± 0.028- − 0.200 ± 0.033 ‰ and − 0.089 ± 0.027- − 0.250 ± 0.049 ‰, respectively), whereas ∆49Tiorthopyroxene-melt shows only a minor fractionation (− 0.002 ± 0.017-0.050 ± 0.025 ‰). The results of this study show that Ti isotope fractionation during mare basalt petrogenesis is expected to be redox dependent and mineral-melt fractionation as commonly determined for terrestrial fO2 may not be directly applied to a lunar setting. This is important for the evaluation of Ti isotope fractionation resulting from lunar magmatism, which takes place under more reducing conditions compared to the more oxidized terrestrial magmatism. [ABSTRACT FROM AUTHOR]

Indirect evidence for the presence of a felsic continental crust, such as the elevated 49Ti/47Ti ratios in Archean shales, has been used to argue for ongoing subduction at that time and therefore plate tectonics. However, rocks of intermediate to felsic compositions can be produced in both plume and island arc settings. The fact that Ti behaves differently during magma differentiation in these two geological settings might result in contrasting isotopic signatures. Here, we demonstrate that, at a given SiO2 content, evolved plume rocks (tholeiitic) are more isotopically fractionated in Ti than differentiated island arc rocks (mainly calc-alkaline). We also show that the erosion of crustal rocks from whether plumes (mafic in average) or island arcs (intermediate in average) can all produce sediments having quite constant 49Ti/47Ti ratios being 0.1-0.3 per mille heavier than that of the mantle. This suggests that Ti isotopes are not a direct tracer for the SiO2 contents of crustal rocks. Ti isotopes in crustal sediments are still a potential proxy to identify the geodynamical settings for the formation of the crust but only if combined with additional SiO2 information. [ABSTRACT FROM AUTHOR]

Typical reconstructions of historic heliospheric magnetic field (HMF) BHMF are based on the analysis of the sunspot activity, geomagnetic data or on measurement of cosmogenic isotopes stored in terrestrial reservoirs like trees (14C) and ice cores (10Be). The various reconstructions of BHMF are however discordant both in strength and trend. Cosmogenic isotopes, which are produced by galactic cosmic rays impacting on meteoroids and whose production rate is modulated by the varying HMF convected outward by the solar wind, may offer an alternative tool for the investigation of the HMF in the past centuries. In this work, we aim to evaluate the long-term evolution of BHMF over a period covering the past twenty-two solar cycles by using measurements of the cosmogenic 44Ti activity (τ1/2 = 59.2 ± 0.6 yr) measured in 20 meteorites which fell between 1766 and 2001. Within the given uncertainties, our result is compatible with a HMF increase from 4.87+0.24-0.30 nT in 1766 to 6.83+0.13-0.11 nT in 2001, thus implying an overall average increment of 1.96+0.43-0.35 nT over 235 years since 1766 reflecting the modern Grand maximum. The BHMF trend thus obtained is then compared with the most recent reconstructions of the near-Earth HMF strength based on geomagnetic, sunspot number, and cosmogenic isotope data. [ABSTRACT FROM AUTHOR]

The article discusses the study that show the delayed formation of silicon carbide (SiC) and carbonaceous grains in type II supernovae (SNe). Topics mentioned include the correlation of the dust grains between Silicon (Si) and Titanium (Ti) excesses, the formation of dust grains showed by Vanadium (V) -Ti chronometer after two years when the parent stars exploded, and the result which supports the calculations on dust condensation of the delayed formation.

Lifetimes of the 2 1 + states in 44 Ti, 48,50 Cr, and 52 Fe were determined with high accuracy exploiting the recoil distance Doppler-shift method. The reduced E2 transition strengths of 44 Ti and 52 Fe differ considerably from previously known values. A systematic increase in collectivity is found for the N = Z nuclei compared to neighboring isotopes. The B ( E2 ) values along the Ti, Cr, and Fe isotopic chains are compared to shell-model calculations employing established interactions for the 0 f 1 p shell, as well as a novel effective shell-model Hamiltonian starting from a realistic nucleon–nucleon potential. The theoretical approaches underestimate the B ( E2 ) values for the lower-mass Ti isotopes. Strong indication is found for particle-hole cross-shell configurations, recently corroborated by similar results for the neighboring isotone 42 Ca. [ABSTRACT FROM AUTHOR]

A γ-spectroscopy study to search for chirality in 193Tl was conducted. Three negative-parity bands with close excitation energies and almost equal B(M1)/B(E2) values were identified. These bands were associated with the same πh9=2 ⊗vi13=2² configuration which is suitable for chiral symmetry. Analysis of the properties of these bands suggested that one or two chiral systems are formed in 193Tl. [ABSTRACT FROM AUTHOR]

Titanium isotopic compositions have been used to elucidate geochemical and cosmochemical processes. Until now, no Ti isotopic reference material has been reported worldwide, which imposes restriction upon analytical method establishment and laboratory quality control. In this paper, a newly prepared Ti isotopic standard solution is introduced. Ti element standard solution offered by the Alfa Company from U.S.A. was chosen as the starting material, based on the comparison of Ti isotopic measurement results of 3 commercially available Ti element standard solutions. The preparation of the new standard solution was strictly followed using the stipulation on reference material of the metrological technical standard of state, including homogeneity and stability tests, and certification analyses. 150 bottles of the solution were prepared, among which 15 bottles were selected randomly for homogeneity test and no detectable heterogeneity was found by F test. The stability inspection through 30 months indicated no significant changes on δTi values. The certified values and uncertainty at the 95% confidence level were shown to be: δ50Ti=-2.23‰±0.14‰, δ49Ti=-1.67‰±0.09‰,δ48Ti=-1.13‰±0.06‰ andδ47Ti=-0.57‰±0.05‰. This newly certified standard solution can be used to calibrate instruments and verify analytical quality in Ti isotope measurements, and compare inter-laboratory data.

We report the results of the deepest Galactic plane (|b| < 17. . 5) survey in the 67.9 and 78.4 keV nuclear de-excitation lines of titanium-44 (44Ti) performed using the data acquired with the IBIS/ISGRI instrument onboard the INTEGRAL satellite during 12 yr of operation. The peak sensitivity of our survey reached an unprecedented level of 4.8 ? 10-6 ph cm-2 s-1 (3σ) that improves the sensitivity of the survey done by Compton Gamma-Ray Observatory/COMPTEL by a factor of ~5. As a result, constraining upper limits for all sources from the catalogue of Galactic supernova remnants (SNRs; Green 2014) are derived. These upper limits can be used to estimate the exposure needed to detect 44Ti emission from any known SNR using existing and prospective X- and gamma-ray telescopes. Among the youngest Galactic SNRs, only Cas A shows significant 44Ti emission flux in good agreement with the NuSTAR measurements. We did not detect any other sources of titanium emission in the Galactic plane at significance level higher than 5σ confirming previous claims of the rarity of such 44Ti-producing SNRs. [ABSTRACT FROM AUTHOR]

In the present work, novel isolated Ti-SBA-15-spherical and Ti-KIT-6 (Si/Ti = 200, 100 and 50) photocatalysts have been synthesized; optimized through N 2 -adsorption/desorption, SEM, EDX, UV–Vis, FT-IR, XPS and TEM analysis techniques; and explored for the photocatalytic reduction of greenhouse gas CO 2 to renewable fuels. The Ti-KIT-6 (Si/Ti = 100) showed better CH 4 production rate (4.15 μmol gcat. −1 h −1 ) than the corresponding Ti-KIT-6-dried (2.63 μmol gcat. −1 h −1 ) and the Ti-SBA-15-calcined/dried (1.85, 3.45 μmol gcat. −1 h −1 , respectively) in the initial optimization reactions. CH 3 OH, CO, and H 2 are the other main fuel products produced by the Ti-KIT-6-calcined (Si/Ti = 100). The increased surface concentration of OH groups found in the Ti-KIT-6-calcined (Si/Ti = 100) than the other two ratios (Si/Ti = 200, 50), the presence of more accessible surface reaction active sites due to the lower number of Ti–O–Ti or TiO 2 agglomerates, and the more isolated Ti species which are uniformly dispersed on the 3-D KIT-6 mesoporous silica support without collapsing the mesoporous structure, have boosted the higher activity, which is even higher than the best commercial Aeroxide P25 TiO 2 . The reaction has been preceded by the competitive adsorption of CO 2 and H 2 O vapors. The UV light source/intensity, H 2 O/CO 2 ratios and catalyst shapes are the key factors that influence the performance of the catalyst, and therefore, these parameters have been optimized to boost the fuel products. [ABSTRACT FROM AUTHOR]

Highlights: [•] WGS reaction mechanism on Pt/Ce1−x Ti x O2−δ was studied by SSITKA-operando methodology. [•] WGS on Pt/Ce0.8Ti0.2O2−δ at 300°C largely follows both the “redox” and “associative formate” mechanisms. [•] CeO2-doped (Zr4+, La3+ and Ti4+) largely affects the concentration of active C-pool and H-pool on Pt/CeO2-doped catalyst. [•] The extent (Δx, nm) of a reactive zone around Pt nanoparticles strongly depends on the dopant. [•] A very good correlation between the active C-pool and the specific WGS reaction rate as a function of dopant exists. [ABSTRACT FROM AUTHOR]

Although the systematics of the Pygmy Dipole Resonance was established in several stable even-even nuclei, the collectivity of this mode, explained in a macroscopic picture as an oscillation of a neutron skin against an isospin symmetric proton-neutron core, is still not well understood. In order to guide the theoretical models, we investigated the heavy odd mass, stable isotopes 203,205Tl using unpolarized bremsstrahlung photon beams at the S-DALINAC facility at TU Darmstadt. The NRF experiments were complemented by measurements at the High Intensity γ-ray Source (HIγS) at the Triangle Universities Nuclear Laboratory (TUNL) in Durham, NC, USA, with a fully linearly polarized quasi-monoenergetic photon beam. Between 4 and 7 MeV, a concentration of dipole strength is observed in the odd-mass nuclide 205Tl. For the 203Tl isotope, two ground-state transitions around 5 MeV could be resolved in the spectra. In this report, the obtained results will be presented. The results for the proton-odd nuclide 205Tl will be compared to the ones for the neighbouring even-even nucleus 206Pb. [ABSTRACT FROM AUTHOR]

Relativistic configuration interaction (RCI) calculations are performed for 291 states belonging to the configurations 1s22s22p, 1s22s2p2, 1s22p3, 1s22s23l, 1s22s2p3l, 1s22p23l, 1s22s24l', 1s22s2p4l' , and 1s22p24l' (l = 0, 1,2 and l' = 0, 1, 2, 3) in boron-like ions Si X and Ti XVIII to Cu XXV. Electron correlation effects are represented in the wave functions by large configuration state function (CSF) expansions. States are transformed from j j-coupling to LS -coupling, and the LS -percentage compositions are used for labeling the levels. Radiative electric dipole transition rates are given for all ions, leading to massive data sets. Calculated energy levels are compared with other theoretical predictions and crosschecked against the Chianti database, NIST recommended values, and other observations. The accuracy of the calculations are high enough to facilitate the identification of observed spectral lines. [ABSTRACT FROM AUTHOR]

Abstract: Oxygen deficient tetragonal phases of SrFe1− x Ti x O3− δ (x >0–0.3) show semiconducting behavior when compared to the metallic, cubic phase of x =0 and δ =0. This study aims at understanding the compositional dependence of ac conductivity as a function of temperature for Ti doped SrFeO3− δ . Complex impedance spectroscopy data is analyzed based on the Cole–Cole type impedance response functions, and Jonscher’s universal power law to explain the dispersive behavior of the electrical conductivity. For the first time, we report a positive temperature coefficient of resistance (PTCR) behavior in SrFe1− x Ti x O3− δ (x =0.2 and 0.3) at ambient pressure and moderate temperatures. The correlation between PTCR and electrical modulus is investigated. The non-linear variation of the conductivity with increase in Ti doping is attributed to the change in Fe–O bond distances and increase in site disorder. [Copyright &y& Elsevier]

Long chain aliphatic ester, isopropyl myristate, was synthesized using energy efficient microwave irradiation technique. The iso propyl myristate forms complexes with titanium tetrachloride in different mole ratios. The nature of chemical bonding between the titanium and the ester functionality was investigated by FTIR and NMR spectroscopy. The performance of synthesized complexes with methylalumoxane as co-catalyst for ethylene polymerization was found to depend on the nature of complex and polymerization parameters. Molecular weight and thermal characteristics of polyethylene was also investigated. [ABSTRACT FROM AUTHOR]

The local structure of titanium in tektites from six strewn fields was studied by Ti K-edge X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) in order to provide quantitative data on Ti-O distance and Ti coordination number. The titanium in tektites possessed different coordination environment types. XANES spectra patterns revealed resemblance to high-temperature TiO2-SiO2 glass and TiO2 anatase. All samples showed that the valence of Ti is 4+. Based on the Ti-O distances, coordination numbers and radial distribution function determined by EXAFS analyses, the tektites were classified into three types: type I, Ti occupies a four-coordinated tetrahedral site with Ti-O distances of 1.84-1.79 Å; type II, Ti occupies a five-coordinated trigonal bipyramidal or tetragonal pyramidal site with Ti-O distances of 1.92-1.89 Å; type III, Ti occupies a six-coordinated octahedral site with Ti-O distances of 2.00-1.96 Å. Although Ti occupies the TiO6 octahedral site in most titanium minerals under ambient conditions, some tektites have four- and five-coordinated Ti. This study indicated that the local structure of Ti might change in impact events and the following stages. [ABSTRACT FROM AUTHOR]

Gene-targeted FLX titanium pyrosequencing integrated with stable isotope probing (SIP) using [13C]biphenyl substrate revealed that tidal mudfiat sediments harbor novel aromatic ring hydroxylating dioxygenases (ARHD). More than 80% of the detected ARHD genes comprise four clades (0.5 distance) with 49 to 70% amino acid identity to sequences in public databases. The 16S rRNA sequences enriched in the 13C fraction were from the Betaproteobacterja, bacilli (primarily Paenibacillus-like), and unclassified phyla. [ABSTRACT FROM AUTHOR]

The Recoil Distance Doppler-Shift method has been used to measure the lifetime of the first 3- state in the N = Z 44Ti nucleus, populated via the 40Ca(6Li, pn)44Ti reaction. State-of-the-art analysis techniques have been employed to determine the experimental lifetime, resulting in a B(Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.) ≈ 3 W.u. [ABSTRACT FROM AUTHOR]

We report on preliminary results from the experiment performed at Legnaro National Laboratories aiming at the investigation of the shape evolution of the 88Mo nucleus. The GDR spectra obtained for two data sets measured at 48Ti beam energy of 300 and 450 MeV corresponding to 3 and 3.8 MeV temperatures, respectively, are presented. The low energy component in GDR strength functions, similar to the theoretical predictions of LSD model, possibly indicates the presence of Jacobi shape transition. [ABSTRACT FROM AUTHOR]

The reactions 48Ti+40Ca at 600, 450 and 300 MeV were employed at the Laboratori Nazionali di Legnaro (LNL) to investigate the charged particles and the Giant Dipole Resonance (GDR) decay of hot rotating 88Mo nuclei. Some preliminary results about Light Charged Particles (LCP) distribution in coincidence with Evaporation Residues (ER) and fusion-fission events selection are shown. [ABSTRACT FROM AUTHOR]

Abstract: Adsorptive features of the composites of polyacrylamide (PAAm) and bentonite (B), and zeolite (Z) were investigated for Tl+ and Tl3+. Langmuir monolayer adsorption capacities for the corresponding ions were 1.85 and 0.97molkg−1 for PAAm–Z and 0.36 and 0.16molkg−1 for PAAm–B. The values of enthalpy and entropy changes were positive for both composites and ions. The compatibility of the second order adsorption kinetics implied that the rate-controlling step was concentration dependent; the sorption process was ion exchange. High adsorption rate was found for both composites; the time required for adsorption of half of Tl+ concentrations was 7min. In the presence of both ions, PAAm–B was more selective for Tl3+ than PAAm–Z. The reusability tests for Tl+ for five uses proved that the composites were reusable after complete recovery of the loaded ion. The values of Tl+ adsorption onto PAAm–Z from solutions containing Fe3+, Pb2+, Zn2+ confirmed that the effect of the presence of these ions on Tl+ extraction was not significant. Although Tl+ sorption decreased with increasing ionic strength (CaCl2) of the medium, the results of adsorption from sea water containing 5×10−6 molL−1 (1mgL−1) of Tl+ ascertained that the composites still adsorbed about 10% of Tl. [Copyright &y& Elsevier]

We have been developing Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS) technique to measure titanium isotopic composition in situ. A principal aim of this work is to search for isotopic heterogeneities larger than the few epsilons (ε, in parts in 104) of the solar system. Our analytical precision of the ratios of 46Ti, 48Ti, and 50Ti to 49Ti after exponential-law mass discrimination correction normalizing 47Ti/49Ti to 1.33375 were about 2.5 ε (2σ. Mixture solutions were prepared by adding the expected level of Ca, Cr, Mg, and A1 to the Ti solutions to demonstrate that our interference correction is effective. We then applied our technique with 213 nm Nd-YAG laser ablation to five Ti-rich terrestrial solids, and all of them also showed titanium isotopic composition that was consistent with one another and agreed with that for the solution standard. It appears that the in situ laser technique did not significantly increase the long-term reproducibility beyond the 2.5 ε established using the solution method. This is an order of magnitude better than the typical precision of a few permil for secondary ion mass spectrometry (SIMS). The combination of the ability to perform in situ analysis on 30 µm spots with e level precision is a niche for LA-MC-ICP-MS. We also ablated two lines on a fassaite gram from a large well studied CAI Egg-6 of the Allende meteorite. After the mass discrimination was corrected by normalizing 47Ti/49Ti, the 46Ti and 48Ti are normal within about 2 ε while 50Ti/49Ti shows a 9 ε excess. These data are in excellent agreement with thermal ionization mass spectrometry (TIMS) results. Comparing our ICP-MS results against the results from TIMS studies, we found that our normal titanium isotopic ratios were closest to the less precise data of Heydegger et al. (1979) who measured Ti+. We support the proposal to IUPAC to change the accepted Ti abundance to that measured by ICP-MS and TIMS without using Ti oxides. [ABSTRACT FROM AUTHOR]

Nanosized TiO2 powder was synthesized via sol-gel method using titanium tetraisopoxide (TPT) as the precursor. Mol ratios of water to TPT were varied from 1 (Powder A), 2 (Powder B), 3 (Powder C), and 4 (Powder D) to evaluate effect of hydrolysis degree. TG/DTA curves showed that amorphous phase turned to anatase crystal structure at ca. 415, 337, 310, and 339°C for Powders A, B, C, and D, respectively. XRD analysis showed that all the synthesized TiO2 powders were 100% in anatase form with Powders B and C showing considerably higher crystallinities. The powders obtained at lower water to TPT mol ratios were spherical in shape and they became bar-like shapes higher mol ratios. The lower hydrolysis degree led to higher surface area of the Powder A (24.8m2/g) compared to Powder B (14.6m2/g). From phenol photocatalytic measurement, Powder B was the most efficient attributed to its higher crystallinity. [ABSTRACT FROM AUTHOR]