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Perovskite solar technology has become a trend topic in the last decade, reaching promising efficiencies up to 25.7 %. Researchers mainly focused on obtaining high performance rather than caring for stability under accelerated stress conditions, such as thermal and light soaking tests. For this reason, we studied a standard triple cation perovskite (∼1.58 eV) and wider bandgap perovskite (∼1.63 eV) with the scope of finding a common strategy to build a robust device stable over time independently of the perovskite used. We use a combination of additives inside the perovskite ink: ionic liquid 1-Butyl-3-methylimidazolium tetrafluoroborate (BMIM-BF4), alkylamine ligands oleylamine (OAm) and benzylhydrazine hydrochloride (BHC). Our work reveals that the combination of these additives helps to improve the efficiency and stability of the entire device, reaching a power conversion efficiency up to 21.3 % and over 20 % for both types of perovskite and stability beyond 1000 h under continuous light soaking. The universal applicability of this method was further applied to a robust methylammonium free perovskite, leading to an impressive stability both under light soaking and under 85 °C, showing T 90 > 1500 h and T 80 > 8658 h, respectively: the solar cells modified with the additive mixture retained 95 % of their efficiency after 1000 h under light soaking at 45 °C and 100 % of their efficiency after 1500 h of stress at 85 °C. [Display omitted] • A universal approach to enhance performances and stability of inverted PSCs by introducing a combination of additives. • 3 types of Perovskite were tested, improving their performances from 14.9 % to up to 21.30 % efficiency. • ISOS L-1 and ISOS T-1 reached a T 90 > 1500 h and a T 80 > 8650 h, respectively. [ABSTRACT FROM AUTHOR]

• Synthesis of nanostructured scheelite (CaWO 4) from wolframite enriched ores. • Mechanochemical activation of wolframite and calcium carbonate (CaCO 3) mixtures. • Quantitative conversion of wolframite and CaCO 3 mixtures into CaWO 4 at T ≤ 700 °C. • No need of CaCO 3 excess to get complete conversion of wolframite into CaWO 4. Nanostructured scheelite (CaWO 4) was synthesized by calcination in air of enriched wolframite (Fe 1−x Mn x WO 4) ore and calcium carbonate (CaCO 3). The effects of process parameters such as milling conditions of the solid reactants, calcination in flowing or static air, and use of stoichiometric excess of calcium carbonate on wolframite conversion into scheelite were studied by X-Ray Diffraction (XRD) and field emission gun scanning electron microscopy (FEG SEM). The intimate mixing and associated decrease in the diffusion path by high-energy planetary ball milling (PBM) were responsible for the conversion of most of wolframite into nanostructured scheelite after 2 h at 600 °C, with no need of calcium carbonate stoichiometric excess. Complete conversion of PBM wolframite:CaCO 3 mixtures into nanosized scheelite, iron oxide and carbon dioxide was accomplished after 2 h at 700 °C. The nanostructured scheelite obtained from wolframite is expected to be significantly more reactive in subsequent treatments (e.g., leaching) for tungsten extraction. [ABSTRACT FROM AUTHOR]

Intranasal delivery is an alternative method to target therapeutics to the central nervous system. In the present study, chitosan glutamate (CG)-based mucoadhesive microspheres containing rokitamycin (RK) were prepared by spray-drying and in vitro characterization. Moreover, the influence of CG on RK absorption in bloodstream and cerebrospinal fluid (CSF) was evaluated after nasal administration to rats. The in vivo results were compared with those obtained after nasal administration of chitosan (CH)-based microparticles containing RK and after intravenous (IV) administration of the free drug. The in vitro results indicate that the concentrations of feed solution or kind of CH influence the RK entrapment and size of microspheres. All formulations increase the solubility of this poorly water-soluble drug, but CG is more able to increase the in vitro dissolution rate of RK than CH. CG microspheres absorb water quickly and then dissolve, whereas CH particles need more volume of water for swelling and gelling. In vivo studies showed that, after IV administration, RK is not able to cross the blood-brain barrier and to reach the CSF from the bloodstream. On the contrary, drug goes to the CSF and the bloodstream only after nasal administration of CG microparticles. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:1488-1502, 2011 [ABSTRACT FROM AUTHOR]