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Self-standing Na3MnTi(PO4)3/carbon nanofiber (CNF) electrodes are successfully synthesized by electrospinning. A pre-synthesized Na3MnTi(PO4)3 is dispersed in a polymeric solution, and the electrospun product is heat-treated at 750 °C in nitrogen flow to obtain active material/CNF electrodes. The active material loading is 10 wt%. SEM, TEM, and EDS analyses demonstrate that the Na3MnTi(PO4)3 particles are homogeneously spread into and within CNFs. The loaded Na3MnTi(PO4)3 displays the NASICON structure; compared to the pre-synthesized material, the higher sintering temperature (750 °C) used to obtain conductive CNFs leads to cell shrinkage along the a axis. The electrochemical performances are appealing compared to a tape-casted electrode appositely prepared. The self-standing electrode displays an initial discharge capacity of 124.38 mAh/g at 0.05C, completely recovered after cycling at an increasing C-rate and a coulombic efficiency ≥98%. The capacity value at 20C is 77.60 mAh/g, and the self-standing electrode exhibits good cycling performance and a capacity retention of 59.6% after 1000 cycles at 1C. Specific capacities of 33.6, 22.6, and 17.3 mAh/g are obtained by further cycling at 5C, 10C, and 20C, and the initial capacity is completely recovered after 1350 cycles. The promising capacity values and cycling performance are due to the easy electrolyte diffusion and contact with the active material, offered by the porous nature of non-woven nanofibers. [ABSTRACT FROM AUTHOR]

GeFe2O4 (GFO) is a germanium mineral whose spinel crystal structure determines its interesting functional properties. Recently, it was proposed for application as an anode for Sodium and Lithium-Ion Batteries (SIBs and LIBs) thanks to its combined conversion and alloying electrochemical mechanism. However, its entire potential is limited by the poor electronic conductivity and volumetric expansion during cycling. In the present paper, pure and Sn or Mg doped GFO samples obtained from mechano-chemical solid-state synthesis and properly carbon coated were structurally and electrochemically characterized and proposed, for the first time, as anodes for SIBs. The spinel cubic structure of pure GFO is maintained in doped samples. The expected redox processes, involving Fe and Ge ions, are evidenced in the electrochemical tests. The Sn doping demonstrated a beneficial effect on the long-term cycling (providing 150 mAh/g at 0.2 C after 120 cycles) and on the capacity values (346 mAh/g at 0.2 C with respect to 300 mAh/g of the pure one), while the Mg substitution was less effective. [ABSTRACT FROM AUTHOR]

Metal hydrides are an interesting group of chemical compounds, able to store hydrogen in a reversible, compact and safe manner. Among them, A2B7-type intermetallic alloys based on La-Mg-Ni have attracted particular attention due to their high electrochemical hydrogen storage capacity (∼400 mAh/g) and extended cycle life. However, the presence of Mg makes their synthesis via conventional metallurgical routes challenging. Replacing Mg with Y is a viable approach. Herein, we present a systematic study for a series of compounds with a nominal composition of La2-xYxNi6.50Mn0.33Al0.17, x = 0.33, 0.67, 1.00, 1.33, 1.67, focusing on the relationship between the material structural properties and hydrogen sorption performances. The results show that while the hydrogen-induced phase amorphization occurs in the Y-poor samples (x < 1.00) already during the first hydrogen absorption, a higher Y content helps to maintain the material crystallinity during the hydrogenation cycles and increases its H-storage capacity (1.37 wt.% for x = 1.00 vs. 1.60 wt.% for x = 1.67 at 50 °C). Thermal conductivity experiments on the studied compositions indicate the importance of thermal transfer between powder individual particles and/or a measuring instrument. [ABSTRACT FROM AUTHOR]

Low-cost and simple methods are constantly chased in order to produce less expensive lithium-ion batteries (LIBs) while possibly increasing the energy and power density as well as the volumetric capacity in order to boost a rapid decarbonization of the transport sector. Li alloys and tin-carbon composites are promising candidates as anode materials for LIBs both in terms of capacity and cycle life. In the present paper, electrospinning was employed in the preparation of Sn/SnOx@C composites, where tin and tin oxides were homogeneously dispersed in a carbonaceous matrix of carbon nanofibers. The resulting self-standing and light electrode showed a greatly enhanced performance compared to a conventional electrode based on the same starting materials that are simply mixed to obtain a slurry then deposited on a Cu foil. Fast kinetics were achieved with more than 90% of the reaction that resulted being surface-controlled, and stable capacities of about 300 mAh/g over 500 cycles were obtained at a current density of 0.5 A/g. [ABSTRACT FROM AUTHOR]

Background: Macroaggregated human serum albumin (MAA) properties are widely used in nuclear medicine, labelled with 99mTc. The aim of this study is to improve the knowledge about the morphology, size, dimension and physical–chemical characteristics of MAA and their bond with 99mTc and 68Ga. Methods: Commercial kits of MAA (Pulmocis®) were used. Characterisation through experiments based on SEM, DLS and Stokes' Law were carried out. In vitro experiments for Langmuir isotherms and pH studies on radiolabelling were performed and the stability of the radiometal complex was verified through competition reactions. Results: The study settles the MAA dimension within the range 43–51 μm. The Langmuir isotherm reveals for [99mTc]MAA: Bmax (46.32), h (2.36); for [68Ga]MAA: Bmax (44.54), h (0.893). Dual labelling reveals that MAA does not discriminate different radioisotopes. Experiments on pH placed the optimal pH for labelling with 99mTc at 6. Conclusion: Radiolabelling of MAA is possible with high efficiency. The nondiscriminatory MAA bonds make this drug suitable for radiolabelling with different radioisotopes or for dual labelling. This finding illustrates the need to continue investigating MAA chemical and physical characteristics to allow for secure labelling with different isotopes. [ABSTRACT FROM AUTHOR]

This paper describes the structure and properties of the drug domperidone and a novel 1:1 domperidone succinate salt. The new salt is characterized by means of thermal, spectroscopic, microscopic and powder diffraction measurements. The crystal structures of the salt and, for the first time, of pure domperidone have been determined by means of single-crystal X-ray diffraction. In both structures, the piperidine ring of domperidone adopts the expected chair conformation, and supramolecular centrosymmetric R2(2)(8) motifs are formed by N-H...O hydrogen bonds between chlorine-substituted oxobenzimidazolyl groups. Further N-H...O hydrogen bonds occur between non-substituted oxobenzimidazolyl groups and the resulting C(4) motifs originates hydrogen-bonded chains, extending along the crystallographic b axis. In the salt, a single N-H...O hydrogen bond forms between the protonated nitrogen of the piperidine ring and the carboxylic O atom of the succinate ion. Two alternative and mutually exclusive positions for the nonsubstituted oxobenzimidazolyl group have also been observed; this disorder makes the hydrogen-bonded chains originating from the bicyclic group polar. The dissolution behaviour of the salt in dosage form is compared with two reference commercial products. The salt shows an increased solubility, a characteristic that could be of great advantage from a pharmaceutical view point.