No abstract available

[en] We disclosed a protocol for the TiCl(OⁱPr)₃-mediated one-pot reductive amination of acetophenone with anilines in good yield. Moreover, the successful one-pot synthesis of new 1,1'-bis(N-aryl-1-aminoethyl)ferrocene derivatives in good yield has been achieved. This protocol is currently being applied for the reductive amination of 3,7-diketosteroid with aryl amines. 1,1'-Disubstituted-ferrocenes, especially bearing chelating nitrogen atoms, are an important class of ligands in organic synthesis. These nitrogen-containing ferrocenes served as [N,N] bidentate ligands to directly coordinate with transition metals for studying structures and mechanisms. 1,1'-Di-aminoferrocenes undergo cycloplatination to produce cyclo-platinated complexes, which exhibit potential medical and biological activities

[en] Highlights: • Three TiCl_3 polymorphs materials were systematically investigated. • Structural results agree well with experimental and available theoretical data. • Morphological and thermodynamic properties were computed and analyzed. • Core-level spectroscopy and work function were obtained. - Abstract: Computer simulation has been widely applied in many research fields owing to its superiority in revealing an insight understanding of the phenomena. In this work, the thermodynamics, core-level spectroscopy, morphology, and work function of TiCl_3 with three different crystalline phases (α, β, and γ) have been comprehensively computed employing the Materials Studio package. Our computational DFT-D approach gives a structural description of the TiCl_3 phases in good agreement with experiment. The core-level spectroscopy confirmed that α, β, and γ modifications for TiCl_3 have lightly affected on the valences of the constitutional elements. A series of possible growth faces (h k l) were deduced using the classic Bravais–Friedel–Donnay–Harker (BFDH) model. We conclude that the sequence of work function for (0 0 1) surface was α > β ≈ γ

[en] Features of the two thin-film techniques, atomic layer deposition (ALD) and molecular layer deposition (MLD), are combined to build up a stable novel inorganic-organic hybrid material of the (-Ti-N-C₆H₄-O-C₆H₄-N-)_n type, deposited from successive pulses of TiCl₄ and 4,4'-oxydianiline precursors. Depositions in the temperature range of 160-230 deg. C resulted in unstable films, while the films obtained in the temperature range of 250-490 deg. C were found stable in atmospheric air. The growth rate increased with increasing temperature, from 0.3 A per cycle at 160 deg. C to 1.1 A per cycle at 490 deg. C.

[en] Titanium nitride (TiN) films were deposited by using plasma-enhanced atomic layer deposition (PEALD) with varying deposition temperature, N₂/H₂/Ar plasma time, and ratio of N₂/H₂/Ar reactant gases. With increasing plasma time, the TiN film density and composition (N/Ti) increased to about 5.03 g/cm³ and 1, respectively. The Ar gas in the reactants may have increased the reactivity of hydrogen and nitrogen radicals, but didn't improve the films' electrical properties after a certain ratio. On the other hand, the ratio of H₂/N₂ gas may have significantly affected the TiN composition (N/Ti ratio) and impurity (Cl content) in the films due to the competitive radical reaction. When the gas ratio of H₂/N₂ was increased from 0.1 to 1, the TiN films exhibited a higher growth rate (0.046 nm/cycle), good electrical resistivity (∼80 μΩ-cm), and very low Cl content (<0.5 at%). Thus, the N₂/H₂/Ar radicals should be a promising reactant as a nitrogen source in PEALD, and the ratio of reactant gas can be used to manipulate the films' composition and reactivity.

[en] Highlights: • N-doped TiO₂ are synthesized via in-situ exposure of TiCl₃ to non-thermal plasma. • Nitrogen loaded depends on exposure time to plasma gaseous reactive species. • N-doped TiO₂ was formed for exposure time higher than 30 min. • Significant photocatalytic activity under daylight irradiation was observed.

No abstract available

[en] Highlights: • Overall tunning way by internal refinement and external decoration is proposed. • Mg-Ni based nanocomposite can be observed by overall tunning strategy. • Synergetic catalytic effect of MWCNTs and TiF₃ on thermodynamics are discussed. • Isothermal hydrogenation hysteresis of modified Mg-rich alloys are investigated. The as-cast Mg-Ni alloy with nominal component Mg-10 wt%Ni (Mg10Ni) is successively modified based on the internal refinement by melt-spinning and external decoration through surface catalysis. The isothermal hydrogenation kinetics, absorption/desorption thermodynamics, hysteresis and non-isothermal desorption of modified Mg-rich alloys are investigated in this work. The results of modification indicate that the alloying and refinement microstructure are the foundation for high capacity and rapid kinetics. The active surface is the precondition to achieve the above-mentioned process. MWCNTs especially MWCNTs coupling with TiF₃ can easily activate the Mg-10 wt%Ni alloy and promote rapid absorption/desorption kinetics by H₂ dissociation and H-atoms auxiliary diffusion. Mg-rich Mg-Ni alloy after internal refinement and external decoration with MWCNTs and TiF₃ possesses superior thermodynamics and hysteresis. As high as 5.5 wt% hydrogen can be rapidly absorbed within 60 s and the endothermic peak is around 374 °C, which shifts toward low temperature as high as ∼75 °C than that of Mg-10 wt%Ni alloy without any catalysts. It is the synergistic catalytic effect originated from the assisted diffusion of MWCNTs and the surface spillover special effects of TiF₃ that promote the outstanding thermodynamics and hysteresis for Mg10Ni-MWCNTs-TiF₃.

[en] The water eutrophication caused by cyanobacteria seasonally proliferates, which is a hot potato to be resolved for water treatment plants. This study firstly investigated coagulation performance of titanium tetrachloride (TiCl₄) for Microcystis aeruginosa synthetic water treatment. Results show complete algal cell removal by TiCl₄ coagulation without damage to cell membrane integrity even under harsh conditions; 60 mg/L TiCl₄ was effective in removing the microcystins up to 85%. Furthermore, besides having stronger UV₂₅₄ removal capability and the higher removal of fluorescent substances over Al- and Fe-based coagulants, TiCl₄ coagulant required more compact coagulation and sedimentation tanks due to its significantly improved floc growth and sedimentation speed. Meanwhile, its’ short hydraulic retention time avoided algal cell breakage and subsequent algal organic matter release. Microcystin concentrations were kept at a low level during sludge storage period, indicating that the TiCl₄ flocs could prevent algal cells from natural lysis. To facilitate water recycling without secondary contamination, the algae-containing sludge after TiCl₄ coagulation ought to be disposed within 12 days at 20 °C and 8 days at 35 °C.

[en] South Africa is endowed with significant titanium-bearing reserves, which are concentrated to produce slag and exported as a low-value commodity, meeting about 20% of the global demand for the production of titanium dioxide pigment. Compared to the well-established titanium pigment industry, the much smaller titanium metals industry holds significant growth potential. Titanium metal is however notoriously difficult to refine from its abundant ores, and machining titanium is known to be challenging. Titanium usage is thus limited to niche applications in aerospace, defence, medical and chemical industries. Titanium powder produced at low cost promises a paradigm shift in titanium market size. Titanium powder has not been produced directly at commercial scale from titanium tetrachloride (TiCl₄), which is the precursor for both pigment and metal production. The Titanium Centre of Competence (TiCOC) at the Council for Scientific and Industrial Research (CSIR) has as its aim the establishment of a titanium metals industry in South Africa. To this end research and development work is being conducted towards the commercialisation of the CSIR-Ti process, a potentially cost-effective method for titanium metal production. This article discusses the history of the CSIR-Ti process for titanium metal powder production, challenges addressed, current development status and the unique products achieved. (paper)