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Contrary to molecular species, only very few solids are reported to host manganese (V) species. Herein, we report three new compounds with a hydroxyapatite structural backbone built on the MnVO43–anion: Sr5[(Mn1–xSix)O4]3(OH)1–3x(x= 0 and 0.053), Sr5(MnO4)3(OH)1–yFy(y= 0.90), and Sr5[(Mn1–xSix)O4]3F1–3x(x= 0.058). These solids are fully characterized using powder X-ray and neutron powder diffraction, scanning transmission electron microscopy, electron energy loss spectroscopy (EELS), thermogravimetric analysis, and magnetic measurements. Especially, we report for the first time EELS Mn–L2,3spectra of manganese with the oxidation state (V). Contrary to other Mn(V) oxides, these solids and the nominal compound Sr5(MnO4)3OH do not comprise Ba2+cations but rely only on Sr2+cations, showing that barium is not a required element to stabilize Mn(V) species in inorganic solids. We show that by tuning soft chemistry conditions on the one hand and post-treatment topological transformation conditions on the other hand, Mn(V) and hydroxyl groups can be substituted by Si(IV) and fluoride ions, respectively. Hence, we deliver solids with a potentially wide composition range. These compounds show significant oxygen anionic conduction, thus suggesting the emergence of new functional materials built from high-oxidation state manganese cations.

Two straightforward methods for glyphosate and AMPA analysis in honey through ion chromatography coupled to Q-Orbitrap accurate high-resolution mass spectrometry as well as their application to real samples are presented. The sample preparation step is accomplished through dilution with methanol–water or water. No pH adjustment is necessary. Recoveries were in the range 80 to 110% with RSDs < 20%. The LOQ of glyphosate was 0.005 mg kg−1, far below the allowed EU-MRL (0.05 mg kg−1) in honey, showing a linear range of 0.005–0.5 mg kg−1and medium matrix effect. LOQ of AMPA was 0.02 mg kg−1. Glyphosate quantitation was performed with internal or external calibration yielding identical results, thus broadening the applicability of the method as isotopically labelled standards are no longer mandatory. The method was applied to 32 honey samples from different origins. Glyphosate was found in 81% of the samples and 41% were above the EU-MRL showing its applicability in routine work. AMPA was not detected in any of the samples.

BaFeCl0.13(2)O2.48(2)has been synthesized and studied. A proper tuning of the synthetic route has been designed to stabilize this compound as a single phase. The thermal stability and evolution, along with the magnetic and structural properties are reported here. The crystal structure has been refined from neutron powder diffraction data, and it is of the type (hhchc)2-10H. It is stable up to a temperature of 900 °C, where the composition reads BaFeCl0.13(2)O2.34(2). The study by electron microscopy shows that the crystal structure suffers no changes in the whole BaFeCl0.13(1)O3–y(2.34 ≤ 3 – y≤ 2.48) compositional range. Refinement of the magnetic structure shows that the Fe is antiferromagneticaly ordered, with the magnetic moment parallel to the abplane of the hexagonal structure. At higher temperature, a nonreversible phase transition into a (hchc)-4H structure type takes place with overall composition BaFeCl0.13(1)O2.26(1). Microstructural characterization shows that, in some crystals, this phase intergrows with a seemingly cubic related phase. Differences between these two crystalline phases reside in the chlorine content, which keeps constant through the phase transition for the former and disappears for the latter.

This article describes an effective full scan new analytical approach for target and non-target screening of volatile organic compounds (VOCs) in water based on an automatic dynamic headspace (DHS) sampler followed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOF-MS). The operational parameters of DHS having influence on the extraction efficiency of water samples were optimized. The performance of a developed method by DHS-GCxGC-TOFMS was assessed with special attention to the capability of an enhanced separation and reliable identification at a trace concentration level in water. For this purpose, 31 target compounds including non-halogenated, mono-, di-, tri- and tetra-halogenated VOCs were selected. DHS-GCxGC-TOFMS allowed fast and automated analysis of VOCs at a level of parts per trillion, with no matrix interference in the different types of water analyzed (drinking water-tap, and bottled, river water and sea water) and with a minimum sample preparation. Excellent method detection and quantification limits were achieved, ranging from 0.01 to 10 ng L−1and from 0.02 to 34 ng L−1, respectively. Good linearity (r2> 0.99), intra and inter-day repeatability (<30%) were obtained for most of the target analytes denoting the suitability of the method for quantifying VOCs and its potential use in a routine setting. This method was successfully applied to real samples. Full mass range TOFMS acquisition allowed for positive identification of both targets, through mass spectral matching to database standards, and non-targeted compounds (dichloroiodomethane and dichloroacetonitrile). Trihalomethanes, tetrachloroethene, benzene, toluene ethylbenzene and xylenes (BTEXs) were the most frequently detected contaminants in the water samples analyzed. Mean concentrations of VOCs ranged from 65–439 ng L−1in sea water, 29–1626 ng L−1in bottled water, 17–16 312 ng L−1in river water and 51–54 460 ng L−1in tap water. The feasibility of using effective software data was very useful to rapidly sort information about the presence of VOCs in water and pattern recognition.

Neutron diffraction and X‐ray absorption near‐edge structure (XANES) studies have been performed in La0.5Ca0.5MnO2.5, La0.5Sr0.5MnO2.5and Nd0.5Sr0.5MnO2.5oxygen‐deficient perovskite compounds obtained by topotactic reduction. They all exhibit a brownmillerite structure with G‐type antiferromagnetic ordering. Mn2+, Mn3+and Mn4+coexist at the octahedral sites, whereas only Mn2+is placed in the tetrahedral positions. A magnetic moment of 1.6 μBhas been detected at the tetrahedral layers, which can be explained by assuming Mn2+is in a low‐spin configuration.

A new 10H polytype has been stabilized in the BaMn1–xFexO3–y system with the composition BaMn0.4Fe0.6O2.73. The anionic composition has been established by a reduction and re-oxidation cycle in the stability range of this phase. The structural characterization was carried out by high-resolution electron microscopy (HREM), electron diffraction, and X-ray diffraction. The structure is closely related to the ideal (hch′ch)2 10H polytype with two oxygen-deficient hexagonal (h′) BaO2–y layers per unit formula. This framework gives rise to blocks of three octahedra sharing faces linked by corners to two corner-sharing tetrahedra.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Two new members of the one-dimensional (A3NiMnO6)α(A3Mn3O9)β homologous series, with the compositions (Sr0.75Ba0.25)5NiMn3O12 and Sr9Ni2Mn5O21, have been synthesised. Their structures can each be described as a hexagonal array of infinite one-dimensional chains of face-sharing polyhedra, running parallel to the c axis and separated by the Sr/Ba cations. The structure of (Sr0.75Ba0.25)5NiMn3O12, which constitutes the (α = 3, β = 2) member of the series, is made up of three face-sharing octahedra linked by one trigonal prism. For Sr9Ni2Mn5O21 (α = 2, β = 1) the sequence of polyhedra along the chains corresponds to a motif consisting of two octahedra−one trigonal prism−three octahedra−one trigonal prism. The manganese atoms occupy the octahedral sites in both phases, while the Ni²⁺ cations are distributed in the trigonal-prismatic sites in a disordered way. Only a small fraction of these (close to 20%) is located at the centres of the trigonal prisms, 80% being displaced towards the rectangular faces of the polyhedra and giving rise to a square-planar-like coordination. Both oxides present twinned microstructures, as evidenced by SAED and HREM. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Two new members of the (A3ZnMnO6)α(A3Mn3O9)β one-dimensional homologous series have been synthesised with the compositions Sr4Mn2ZnO9 and Ba5Mn3ZnO12. Their structures can be described as a hexagonal array of infinite 1D-chain polyhedra, running parallel to the c-axis, formed by two face-sharing octahedra linked by one trigonal prism for Sr4Mn2ZnO9, and one more octahedron between prisms for Ba5Mn3ZnO12. Both oxides have a twinned microstructure as evidenced by SAED and HREM. Sr4Mn2ZnO9 shows a pronounced antiferromagnetic character with a broad susceptibility maximum at 100 K due to short-range ordering. At low temperature, the susceptibility data suggest a transition to a 3D long-range ordering. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

The (α=3, β=2) member of the (A3A′BO6)α(A3B3O9)βhomologous series has been stabilised in the Sr‐Rh‐O system for a [Sr10(Sr0.5Rh1.5)TP(Rh6)Oh]O24composition. The structural characterisation has been performed by powder X‐ray and electron diffraction measurements and high‐resolution electron microscopy. In this structure, three face‐sharing [RhO6] octahedra linked by one [Rh/SrO6] trigonal prism comprise the infinite one‐dimensional chain that runs parallel to the caxis of a trigonal unit cell (P$\bar 3$c1), with parameters a=9.6411(1) and c=21.2440(4) Å.

The α = 3, β = 6 term of the series (A3B2O6)α (A3B3O9)β has been synthesized in polycrystalline form. The structural characterization by powder X-ray diffraction, electron diffraction and high-resolution electron microscopy indicates that this material is isostructural with Ba9Co8O24. In the structure, seven face-sharing octahedra alternate with a trigonal prism defining chains running parallel to the c axis of a rhombohedral unit cell (R$\bar 3$ c), with parameters a = 1.00766(4) nm and c = 4.1571(2) nm. The structural refinement shows the presence of a small percentage of Rh vacancies leading to the composition Ba9Rh7.92O24. Pauli paramagnetic behaviour is observed. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

A selective and sensitive chromatographic method is described for the determination of nine organochlorine and organophosphorus pesticides in vegetable samples by gas chromatography–mass spectrometry. The proposed method combines the use of positive and negative chemical ionisation and tandem mass spectrometric fragmentation, resulting in a significant increase in selectivity and allowing the simultaneous confirmation and quantification of trace levels of pesticides in complex vegetable matrices. Parameters relative to ionisation and fragmentation processes were optimised to obtain maximum sensitivity. Repeatability and reproducibility studies yielded relative standard deviations lower than 25% in all cases. Identification criteria, such as retention time and relative abundance of characteristic product ions, were also evaluated in order to guarantee the correct identification of the target compounds. The method was applied to real vegetable samples to demonstrate its use in routine analysis.

A simple, rapid and sensitive multiresidue method has been developed for the determination of ten organophosphorus and organochlorine pesticides, commonly used in crop protection. The analysis uses a miniaturised extraction with ethyl acetate followed by large volume injection (10 μL) GC-EI-MS analysis in SIM (selective ion monitoring) mode. Sensitivity and selectivity of the method were acceptable with limits of detection (LODs) lower than 0.01 mg kg⁻¹, except for endosulfan α and β (0.05 mg kg⁻¹). Average recoveries of between 63–99% were obtained and good linearity was observed in the range from 0.01 to 1.00 mg kg⁻¹. Repeatability and reproducibility studies yielded relative standard deviations lower than 20% in all the cases. The method was applied to the analysis of 110 tomato, pepper and cucumber samples, as part of the monitoring programme of the Association of Producers and Exporters of Fruits and Vegetables of Almería.

Vascular microcalcifications are associated with atherosclerosis plaque instability and, therefore, to increased mortality. Because of this key role, several imaging probes have been developed for their in vivoidentification. Among them, [18F]FNa is the gold standard, showing a large uptake in the whole skeleton by positron emission tomography. Here, we push the field toward the combined anatomical and functional early characterization of atherosclerosis. For this, we have developed hydroxyapatite (HAP)-multitag, a bisphosphonate-functionalized 68Ga core-doped magnetic nanoparticle showing high affinity toward most common calcium salts present in microcalcifications, particularly HAP. We characterized this interaction in vitroand in vivo, showing a massive uptake in the atherosclerotic lesion identified by positron emission tomography (PET) and positive contrast magnetic resonance imaging (MRI). In addition, this accumulation was found to be dependent on the calcification progression, with a maximum uptake in the microcalcification stage. These results confirmed the ability of HAP-multitag to identify vascular calcifications by PET/(T1)MRI during the vulnerable stages of the plaque progression.

The synthesis and microstructural characterization, by means of selected‐area electron diffraction and high‐resolution electron microscopy, of Ba7Rh6O18 is reported. This material, isostructural to Ba7Co6O18, is formed by rows of one trigonal prism and five face‐sharing octahedra running parallel to the c‐axis of a trigonal unit cell, with parameters a = 1.004(5) and c = 3.165(7) nm. The substitution of Sr by Ba is accommodated by means of twin formation due to a rearrangement of the rows of polyhedra.

The cover picture shows the electron diffraction pattern, high resolution electron microscopy and a structural model of Ba9Rh7.92O24, the α = 3, β = 6 member of the one-dimensional (A3B2O6)α(A3B3O9)β homologous series. Seven octahedra sharing faces alternate with a trigonal prism defining chains of Rh atoms running parallel to the c axis of a rhombohedral unit cell (R3¯c), separated by Ba atoms. Electron diffraction allows the direct observation of the α and β structural blocks forming such a commensurate modulated structure as well as the superstructure direction. Details are discussed in the article by J. M. González-Calbet et al. on p. 805 ff.

This paper covers innovative issues to obtain energy from the roads through projects and studies that improve the road safety and sustainability. From the recycling of the unused energy braking forces that can recharge the future electric vehicles in vials until the special energy of the sun during the day to inform us in adverse environmental conditions, using holograms on our roadways. Geothermal pavement applications defrosting a way by reusing the heat, or the conversion of an impact energy in an accident against a security barrier into a SOS interpreting the data instantly. Use of low temperature asphalt more environmentally friendly or lighting control to improve the performance. Measures very different, studying or applied, that will save us nearly a 20% the management and maintenance of the road today. [ABSTRACT FROM AUTHOR]