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The concept of co-amorphous systems is introduced in an integrated laboratory experiment, designed for advanced chemistry students, using solvent-free, environmentally friendly mechanochemistry. The dual-drug naproxen-cimetidine co-amorphous system (NPX-CIM) is investigated as an example of the emergent field of medicinal mechanochemistry. Students are trained in solid-state characterization techniques including X-ray powder diffraction, Fourier-transform infrared spectroscopy, and thermal analysis by differential scanning calorimetry. This lab experiment also provides an opportunity to discuss the relevance of different solid forms of pharmaceutics, emphasizing particular properties of disordered materials. This experiment can easily fit the curriculum of any Chemistry or Pharmacy master level degree in courses dealing with instrumental analysis, solid state chemistry, or green chemistry, for classes of 6 to 18 students, in a 5-h lab session. Suggestions to adapt it to the use of a single characterization technique are provided.

The stigma attached to mental disorders remains a public health challenge, represents an important barrier to healthcare and widens existing social inequalities.

Water use and socio-economic development are interconnected in complex ways. Causalities are not easy to identify but it is evident that a nexus between water use and socio-economic development does exist. Considering the diversity of national situations relating to these interrelated phenomena, its study should be considered from a global perspective. This article critically reviews the literature and information from official sources on the relevance of water use and circular economy in order to create a global picture, linking water with socio-economic development. Data from 195 countries was analyzed statistically. A factor analysis defined five essential latent dimensions on the nexus between water use and socio-economic development: development and basic services, population and resource, economic volume, health and well-being, and population density. Based on the identified factors, countries were classified into six groups: Global South in difficulty, global semi-periphery, advanced economy, Middle East and other Global South developing economy, global weight, and small highly developed economy. The clustering results clarify connections between water use conditions and socio-economic development. Understanding the variety of national profiles is helpful to reveal the magnitude and urgency of dealing with the nexus between water use and socio-economic development for many countries.

Tortola bean leaves are an agricultural by-product from Tortola beans, which is widely consumed in Chile. Free, esterified, etherified, and insoluble-bound phenolics of Tortola bean leaves were evaluated for total phenolic content (TPC), antioxidant properties, and phenolic profile using UPLC–MS/MS for the first time, thus all results presented are novel considering previous literature. The soluble phenolics (free + esterified + etherified) presented higher TPC values (4667.03 μg gallic acid equivalent/g dry weight), reducing power (1474.26 mmol Trolox equivalent/100 g dry weight) and antioxidant activity towards peroxyl radicals (245.24 mmol Trolox equivalent/100 g dry weight). The free phenolics fraction showed the highest TPC and equal or higher antioxidant properties in chemical assays. Furthermore, it showed the highest phenolics content as evaluated by UPLC–MS/MS, regardless of the fraction (free, esterified, etherified, or insoluble-bound). Quercetin and rutin derivatives were the most abundant compounds (323.12–421.31 μg/g dry weight), mainly in the fraction containing free phenolics (50%). Free phenolic enriched in quercetin and their derivatives exhibited similar antioxidant protection to those of commercial quercetin in Caco-2 cells subjected to an oxidative challenge induced by exogenous hydrogen peroxide. Tortola bean leaves thus merit further consideration from academia and industry to develop nutraceuticals and/or functional foods.

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The improvement of geotechnical properties is often achieved by the addition of traditional binders, such as cement or lime. However, the use of such binders implies a considerable financial and environmental cost that needs to be mitigated. An unconventional solution, similar to cement in terms of performance but more environmentally friendly, consists in the use of binders made from alkaline activated industrial residues. The technique consists on the activation of raw materials (such as fly ash or blast furnace slag) rich in Si, Al, or even Ca, with high pH alkaline solutions. The present work was developed aiming the possible stabilisation, using different fly ash contents, of a clayey soil with sand. The activator solution was composed of sodium hydroxide and sodium silicate. The extended experimental campaign included unconfined compressive strength (UCS), California Bearing Ratio (CBR), pulse velocity tests and triaxial tests to assess the geomechanical improvement induced by the new binder. As a mean of comparison, the experimental campaign included also the stabilisation of the same soil with either cement or lime. The obtained data indicates that the use of alkaline activation as a soil stabilisation technique provides competitive geomechanical results, when compared with those obtained with traditional binders.

Plastic crystals, frequently observed for compounds with globular molecules, are mesophases characterized by orientational disorder maintaining positional order. The present work focuses on finding correlations between the plastic crystal formation ability of pinanediol, its molecular shape, and the intermolecular interactions existing in solid phases. Pinanediol, a bicyclical monoterpenoid and vicinal diol, is a globular molecule capable of forming intermolecular hydrogen bonds. In the present work, the structure and thermal behavior of this compound in the solid state is studied for the first time. Despite its strong intermolecular interactions in condensed phases, it was found to be a plastic crystal former showing complex polymorphism. Three ordered phases were identified by differential scanning calorimetry, polarized light thermal microscopy, and X-ray diffraction with variable temperature. The molecular dynamics in different polymorphic forms was studied by broadband dielectric spectroscopy (BDS). The structure of the most stable enantiopure ordered polymorph of pinanediol was resolved by single-crystal X-ray diffraction, using crystals of both enantiomers. Its intermolecular close contacts were studied by Hirshfeld surface analysis, which was used to determine shape parameters correlated to plastic crystal formation ability. It was concluded that the globular shape of pinanediol allows the formation of the plastic phase that is not inhibited by the presence of intermolecular hydrogen bonding.

Thénard’s blue (CoAl2O4), Rinman’s green (CoZnO2), and Berzelius’ red (CoMgO2) are pigments that have been used from the 19th century in works of art. Their synthesis can be conducted by a very simple and rapid method: by ignition of a wafer of dried filter paper soaked first in a Co2+solution and then subsequently soaked in a partner salt (Al3+, Zn2+, or Mg2+) solution. Through their following characterization using X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM), the students can be introduced to further concepts, protocols for sample preparation, and data interpretation regarding these mainstream characterization techniques. Although originally designed for first-year undergraduates, this activity can be tailored to match different levels and can be used as a part of STEAM (science, technology, engineering, arts, and mathematics) activities in middle/high school and general public outreach.

Different methods were explored for the amorphization of ranolazine, a sparingly soluble anti-anginal drug, such as mechanochemistry, quench-cooling, and solvent evaporation from solutions. Amorphous phases, with Tgvalues lower than room temperature, were obtained by cryo-milling and quench-cooling. New forms of ranolazine, named II and III, were identified from the relaxation of the ranolazine amorphous phase produced by cryo-milling, which takes place within several hours after grinding. At room temperature, these metastable polymorphs relax to the lower energy polymorph I, whose crystal structure was solved in this work for the first time. A binary co-amorphous mixture of ranolazine and tryptophan was produced, with three important advantages: higher glass transition temperature, increased kinetic stability preventing relaxation of the amorphous to crystalline phases for at least two months, and improved aqueous solubility. Concomitantly, the thermal behavior of amorphous tryptophan obtained by cryo-milling was studied by DSC. Depending on experimental conditions, it was possible to observe relaxation directly to the lower energy form or by an intermediate metastable crystalline phase and the serendipitous production of the neutral form of this amino acid in the pure solid phase.

Phytochemical investigations of the ethanolic extract of leaves of Clutia lanceolata(Family: Euphorbiaceae) resulted in the isolation of four compounds viz. 3,4-dihydroxy-2-methylbenzoic acid (1), 2,2′-dihydroxy-1,1′-binaphthyl (2), 1,3,8-trihydroxy-6-methylanthracene-9,10-dione (3) and 5-hydroxy-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,4,6-trien-3-one (4). Although all the isolated compounds were known but this was the first report from this plant source. Their structures were established on the basis of chemical and physical evidences viz. elemental analysis, FT-IR, 1H-NMR, 13C-NMR and mass spectral analysis. Structure of compound 2and 4was further authenticated by single-crystal X-ray analysis and density functional theory calculations. The isolated compounds (1–4) were screened for AChE enzyme inhibition assay in which compound 3and 4were found to be more potent AChE inhibitor. Molecular docking study of potent AChE inhibitor was performed to find the probable binding mode of the compounds into the active site of receptor. Moreover, the isolated compounds were also screened for in vivo cytotoxicity by brine shrimp lethality assay.

Considering the absence of standards for culture collections and more specifically for biological resource centers in the world, in addition to the absence of certified biological material in Brazil, this study aimed to evaluate a Fungal Collection from Fiocruz, as a producer of certified reference material and as Biological Resource Center (BRC). For this evaluation, a checklist based on the requirements of ABNT ISO GUIA34:2012 correlated with the ABNT NBR ISO/IEC17025:2005, was designed and applied. Complementing the implementation of the checklist, an internal audit was performed. An evaluation of this Collection as a BRC was also conducted following the requirements of the NIT-DICLA-061, the Brazilian internal standard from Inmetro, based on ABNT NBR ISO/IEC 17025:2005, ABNT ISO GUIA 34:2012 and OECD Best Practice Guidelines for BRCs. This was the first time that the NIT DICLA-061 was applied in a culture collection during an internal audit. The assessments enabled the proposal for the adequacy of this Collection to assure the implementation of the management system for their future accreditation by Inmetro as a certified reference material producer as well as its future accreditation as a Biological Resource Center according to the NIT-DICLA-061.

Solution-processed near-infrared organic light-emitting diodes (NIR-OLEDs) with structure glass/indium–tin oxide/poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate)/Er-complex/Ca/Al based on a novel Er(III) complex, [Er(tfnb)3(bipy)] (Htfnb = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione and bipy = 2,2′-bipyridine) have been manufactured and their properties have been studied. A complete quenching of the organic ligand visible emission is shown, and only the sensitized 1.5 μm electroluminesce from Er(III) results. From the electrical characteristic we present the mobility dependence on applied voltage using a numerical model, comparing it to poly(9,9-dioctylfluorene), a commercial semiconducting polymer with optical properties close to those of the molecular ligands. The synthesis of the novel complex together with a detailed analysis of its structure elucidated by XRD, 1H NMR, Raman, and Fourier-transform infrared spectroscopies is presented. A wide-ranging characterization of its photophysical properties in terms of absorption and steady and transient photoluminescence is used to investigate the energy-transfer process from the organic ligand to the central Er(III) ion.

The crystal structure of (µ3-Oxo)-hexakis(µ2-cyanoacetato)-triaqua-tri-iron(III) nitrate pentahydrate shows that the trinuclear ferric complex has an equilateral molecular structure which is manifested in the 57Fe Mössbauer spectrum single doublet. The magnetic measurements reveal antiferromagnetic exchange interactions of –22.85 cm-1, between the metal centers, that compel the system to a total spin ground state of S = ½.

A new vanadium complex [ V(C12H8N2) ·O2·(H2O)]·NO3·H2O h as been synthesized from a simple reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. Monoclinic, P2(1)/c. a = 9.5137(2) Å b = 19.3181(4) Å c = 7.51800(10) Å α=γ=90 β= 93.6830. V= 1378.85(4) Å3. Z=2. Rgt(F) = 0.0255, wRref(F2) = 0.0809. T= 273(2) K. The compound consisted of a [ V(C12H8N2) ·O2·(H2O)]+ cation, one NO3- anion and one water molecular. Molecule structure is stabilized by OHN , OHO intramolecular and intermolecular hydrogen bonds.

Petroleum ether-benzene extract of the leaves of Ficus krishnae afforded a novel halogenated 2H-chromen-2-one named 3-chloro-7-methoxy-4-methyl-chromen-2-one. Its structure was established on basis of chemical and physical evidence (IR, 1H NMR, and MS data) as well as on X-ray crystallographic studies.

The reactivity of allenic esters towards activated Nsulfonylimines in the presence of DABCO was explored. A formal [2+2] cycloaddition of benzyl buta2,3dienoate and Narylidenebenzenesulfonamides yielded mainly 2methyleneazetidines. Interestingly, a DABCOcatalysed reaction of 2,3allenoates, bearing a chiral auxiliary on the ester moiety, with Narylidenebenzenesulfonamides led to optically active azaBaylis–Hillman products and 2azetine derivatives.

In this study the synthesis of an amorphous polymer network, poly[oxymethylene-oligo(oxyethylene)], designated as aPEO, is described. This polymer has been characterized by gel permeation chromatography, thermal analysis, conductivity measurements, evaluation of electrochemical stability and nuclear magnetic resonance spectroscopy. The synthetic procedure developed permits partial fractionation of the product of the polymerization reaction. This host appears to be a promising polymer for application in batteries and electrochromic devices since it provides access to amorphous linear macromolecules with good mechanical properties and promising electrochemical behavior.