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Heterostructures that consist of a germanium antimony telluride matrix and cobalt germanide precipitates can be obtained by straightforward solid-state synthesis including simple annealing and quenching procedures. The microscale precipitates are homogeneously distributed in a matrix with pronounced "herringbone-like" nanostructure associated with very low thermal conductivities. In comparison to the corresponding pure tellurides, the figure of merit (ZT) values of heterostructured materials are remarkably higher. This is mostly due to an increase of the Seebeck coefficient with only little impact on the electrical conductivity. In addition, the phononic part of the thermal conductivity is significantly reduced in some of the materials. As a result, ZT values of ca. 1.9 at 450 °C are achieved. Temperature-dependent changes of the thermoelectric properties are well-understood and correlate with complex phase transitions of the telluride matrix. However, the high ZT values are retained in multiple measurement cycles. [ABSTRACT FROM AUTHOR]

Collaborative conservation brings diverse stakeholders together to sustain healthy landscapes and strengthen communities. Organizations fostering collaborative conservation depend on philanthropy to advance collaborative conservation, while philanthropic organizations depend on these organizations to advance their missions. Both face challenges engaging with each other as they work toward shared goals, yet open dialogue about how funders and practitioners work together is rare. The authors of this paper represent equal numbers of funders and practitioners who, together, identified eight best practices that are practical, effective actions funders and practitioners can take to better achieve shared conservation goals. These eight best practices are: (1) collaborate, (2) nurture relationships, (3) invest in capacity, (4) plan well, implement well, (5) engage diversity, (6) support entrepreneurial spirit, (7) reduce burdens, and (8) tell our story. By centering around collaboration, relationships, and diversity, these best practices exemplify several growing and valuable trends in philanthropy that support collaborative conservation. [ABSTRACT FROM AUTHOR]

Abstract: Highly porous Ru/Se/C electrocatalysts have been successfully synthesized via a template-based method, which was carried out by the impregnation of a hard template (silica gel) with a mixture of RuCl3·xH2O, SeO2 and sucrose dissolved in water. The resulting Ru/Se/C catalysts show good catalytic activity for oxygen reduction in acidic media. The electrocatalysts are believed to consist of selenium-modified ruthenium nanoparticles, which are embedded in a high surface area carbon matrix. The structural properties of the prepared Ru/Se/C electrocatalysts were investigated using nitrogen physisorption measurements, X-ray diffraction and transmission electron microscopy. The elemental composition of prepared Ru/Se/C electrocatalysts was determined using electron microprobe. The catalytic activity was tested using the rotating-ring-disk-electrode technique in 0.1M HClO4 solution at room temperature. [Copyright &y& Elsevier]

In recent years, the navigation capabilities of mobile robots in off-road environments have increased significantly, opening up new potential applications in a variety of settings. By accurately identifying different types of terrain in unstructured environments, safe automated navigation can be supported. However, to enable safe path planning and execution, the traversability costs of the terrain types need to be accurately estimated. Such estimations are often performed manually by experts who possess information about the environment and are familiar with the capabilities of the robotic system or using simplified experiments. In this paper, we present an automated pipeline for generating traversability costs that use recorded locomotion data from a realistic experiment and descriptive information on the terrain obtained from earth observation data. The main contribution is that the cost estimation for different terrain types is based on locomotion data obtained in realistic standardized experiments. Moreover, by repeating the experiments with different robot systems we are easily able to reflect the actual capabilities of the systems. Experiments were conducted in an alpine off-road environment to record locomotion data of four different robot systems and to investigate the performance and validity of the proposed pipeline. The recorded locomotion data for the different robots are publicly available at https://robonav.ist.tugraz.at/data/ • Pipeline to estimate traversability costs for robots using recorded locomotion data. • Interpolation of costs for uncovered terrain classes using order relations. • Realistic off-road locomotion datasets for four heterogeneous robots. • Provision of guidelines for robot-specific recording of locomotion data. [ABSTRACT FROM AUTHOR]

Ge 3 MnSb 2 Te 7 and Ge 3.5 Mn 0.5 Sb 2 Te 7 are doped variants of Ge 4 Sb 2 Te 7 , a material from the homologous series (GeTe) n Sb 2 Te 3 . Phase purity was confirmed by ICP-AES, EDX and quantitative yield according to powder X-ray diffraction. Quenched solid solutions are metastable and exhibit a rocksalt-type average structure and contain multiply twinned domains with superstructures. At ∼300 °C, a phase transition leads to a trigonal layered phase, predominantly corresponding to the 33 R -Ge 3 As 2 Sb 6 type. However, traces of a rocksalt-type phase remain. A rocksalt-type high-temperature phase forms between 500 °C and ∼590 °C. EPR spectra reveal the oxidation state +II for Mn [ g = 2.001(5)], which is also supported by an effective magnetic moment μ eff = 5.713 μ B . The Mn 2+ content of 7.2(5) at% as derived from the magnetic susceptibility agrees with the nominal content of 7.7 at%. A temperature-dependent change in the line width and shape of the EPR signal below 20 K indicates magnetic ordering, which is in agreement with magnetic measurements. A paramagnetic Curie temperature Θ P = −43 K indicates antiferromagnetic fluctuations that set in at ∼50 K. Mn doping reduces the electrical conductivity, while the Seebeck coefficient increases significantly up to 190 μV/K. The thermoelectric properties are affected by the phase transitions. In a first heating cycle, ZT reaches a maximum of ∼0.5 below 300 °C and again at 500 °C. After the first cycle the first maximum disappears as the metastable phase is accessible only by quenching, but the second one is reproducible. Compared to Ge 4 Sb 2 Te 7 , the ZT value of Mn-doped samples is higher for the quenched phase and at high temperatures. [ABSTRACT FROM AUTHOR]

Anhand der Strukturanalyse des neuartigen Sulfidtellurids Pb8Sb8S15Te5 wird eine neue, vielseitig anwendbare Vorgehensweise vorgestellt, die den Synergismus von Elektronenmikroskopie und Beugungsexperimenten mit Synchrotronstrahlung für genaue Strukturanalysen von Nebenphasen in heterogenen mikrokristallinen Proben nutzt. Geeignete Kristallite unbekannter Phasen können mittels Transmissionselektronenmikroskopie identifiziert und mithilfe von Röntgenfluoreszenz ‐ Scans in einem mikrofokussierten Synchrotronstrahl wiedergefunden und zentriert werden. Das verfeinerte Strukturmodell wird anschließend durch Simulation von HRTEM ‐ Abbildungen desselben Kristallits bestätigt. Pb8Sb8S15Te5 besteht aus Ketten heterocubanartiger Einheiten. Die Kationenkoordinationspolyeder bilden ungewöhnlich verschlungene Ketten kanten ‐ und flächenverknüpfter doppelt überkappter trigonaler Prismen. Die Strukturdaten sind ausreichend präzise für Bindungsvalenzrechnungen, die die fehlgeordnete Atomverteilung überzeugend bestätigen. Diese Methode ermöglicht die Optimierung der physikalischen Eigenschaften. Die Rosinen herauspicken: Die komplementäre Anwendung von Elektronenbeugung und mikrofokussierter Synchrotronstrahlung erlaubt innovative Strukturanalysen neuartiger Verbindungen in mikrokristallinen, heterogenen Materialien. Das Sulfidtellurid Pb8Sb8S15Te5 wurde auf diese Weise entdeckt. Es hat eine ungewöhnliche tetragonale Struktur mit Baueinheiten, die dem NaCl ‐ Typ ähnlich sind, aber auch kettenartige Strukturelemente, wie sie typisch für Sulfide sind. [ABSTRACT FROM AUTHOR]

The structure elucidation of the novel sulfide telluride Pb8Sb8S15Te5 demonstrates a new versatile procedure that exploits the synergism of electron microscopy and synchrotron diffraction methods for accurate structure analyses of side-phases in heterogeneous microcrystalline samples. Suitable crystallites of unknown compounds can be identified by transmission electron microscopy and relocated and centered in a microfocused synchrotron beam by means of X-ray fluorescence scans. The refined structure model is then confirmed by simulating HRTEM images of the same crystallite. Pb8Sb8S15Te5 consists of chains of heterocubane-like units. Cation coordination polyhedra form unusually entwined chains of edge- and face-sharing bicapped trigonal prisms. The structure data are precise enough for bond-valence calculations, which confirm the disordered atom distribution. On this basis, optimization of physical properties becomes feasible. [ABSTRACT FROM AUTHOR]

Ag0.8In2.4Te4 (= AgIn3Te5) and Ag0.5In2.5Te4 (= AgIn5Te8) form solid solutions with CdIn2Te4, which are interesting as materials for photovoltaics or with respect to their thermoelectric properties. The corresponding crystal structures are related to the chalcopyrite type. Rietveld refinements of high-resolution synchrotron powder diffraction data measured at K-absorption edges of Cd, Ag, In, and Te and electron diffraction reveal the symmetry as well as the element and vacancy distribution in Ag0.8In2.4Te4 (= AgIn3Te5)/Ag0.5In2.5Te4 (= AgIn5Te8) mixed crystals such as Ag0.25Cd0.5In2.25Te4 and Ag0.2Cd0.75In2.1Te4. All compounds of the solid solution series (CdIn2Te4)x(Ag0.5In2.5Te4)1-x exhibit the HgCu2I4 structure type (space group I42m) with completely ordered vacancies but disordered cations. The uniform cation distribution and thus the local charge balance are comparable to that of CdIn2Te4. In contrast, Ag0.8In2.4Te4 (= AgIn3Te5) crystallizes in the space group P42c with disordered cations and partially ordered vacancies. This is corroborated by bond-valence sum calculations and the fact that there is a Vegard-like behavior for compounds with 0.5 < x in the pseudobinary system (CdIn2Te4)x(Ag0.8In2.4Te4)1-x. Owing to the different structures, there is no complete solid solution series between CdIn2Te4 and AgIn3Te5. All compounds in this work are n-type semiconductors with a low electrical conductivity (~1 S/m) and rather high absolute Seebeck coefficients (up to -750 μV/mK; 225 °C). Electrical band gaps (Eg) determined from the Seebeck coefficients as well as (more reliably) from the electrical conductivity range between 0.19 and 1.13 eV. [ABSTRACT FROM AUTHOR]

Hydrogenation of p-nitrophenol (PNP) to p-aminophenol (PAP) using NaBH4 as a reducing agent was studied as a test reaction for determining the catalytic activity of supported Pt catalysts. The initial reaction rate, which is accessible within less than 10 min via online UV-vis spectroscopy at room temperature, ambient pressure, and in water as solvent, was applied as measure for catalytic activity. For three Pt catalysts supported on porous SiO2, porous glass, and Al2O3, respectively, significant differences in the catalytic activity by almost one order of magnitude were observed. However, especially in the case of very active catalysts, limitations of the reaction by internal or external mass transfer have to be considered. [ABSTRACT FROM AUTHOR]

Highlights: [•] Polymer composites were prepared using a sol–gel synthesized BaTiO3. [•] BaTiO3 surface hydroxyle groups act as linkers for surfactant molecules. [•] The effect of chemical adjustment between surfactant and polymer host is studied. [•] A positive effect of an additional dispersant was found. [•] Dielectric properties of the resulting composite films are presented. [Copyright &y& Elsevier]

Abstract: Mesoporous carbon materials with highly dispersed platinum nanoparticles have been prepared by a one-pot template-assisted synthesis route. Different amounts of hexachloroplatinic acid were added to a silica–sucrose mixture and heat treated in nitrogen and hydrogen flow. The obtained Pt/C materials have been investigated by means of transmission electron microscopy, X-ray photoelectron spectroscopy, nitrogen adsorption at 77K, thermo gravimetric analysis, powder X-ray diffraction, and infrared monitored CO adsorption experiments. Further, Pt/C materials have been used in the liquid-phase oxidation of glucose to gluconic acid to determine their catalytic performance. It has been found that the platinum nanoparticles are partially embedded in the carbon material. However, the Pt sites are accessible for adsorption, and the Pt/C catalysts show good catalytic activity compared to materials prepared by impregnation/reduction. The partial embedding of the Pt nanoparticles accounts for the enhanced leaching stability of the Pt phase during long-term use. [Copyright &y& Elsevier]

The heteroepitaxial growth process of InAs nanowires (NW) on GaAs $[\bar{1}\bar{1}\bar{1}]_{\mathrm{B}}$ substrate was investigated by X-ray grazing-incidence diffraction using synchrotron radiation. For crystal growth we applied the vapor–liquid–solid (VLS) growth mechanism via gold seeds. The general sample structure was extracted from various electron microscopic and X-ray diffraction experiments. We found a closed Ga xIn1− xAs graduated alloy layer at the substrate to NW interface which was formed in the initial stage of VLS growth with a Au–Ga–In liquid alloy. With ongoing growth time a transition from this VLS layer growth to the conventional VLS NW growth was observed. The structural properties of both VLS grown crystal types were examined. Furthermore, we discuss the VLS layer growth process. [ABSTRACT FROM AUTHOR]

The Mn-doped compounds Ge3MnSb2Te7 and Ge3.5Mn0.5Sb2Te7 are prepared from stoichiometric mixtures of the elements (silica ampules, 950 °C for 24 h, quenching and subsequent annealing at 550 °C for 96 h). [ABSTRACT FROM AUTHOR]

Polycrystalline Pb8Sb8S15Te5 is prepared by heating stoichiometric amounts of the elements (1. [ABSTRACT FROM AUTHOR]

Competing Interests: Jeffrey A. Klein owns HK Surgical, Inc (a surgical supply and equipment company that develops infiltration pumps that can be used for Tumescent Drug Delivery). Jeffrey A. Klein and Paytra A. Klein have patents regarding Tumescent Drug Delivery.

Pseudobinary phases (SnSe) x Bi 2 Se 3 exhibit a very diverse structural chemistry characterized by different building blocks, all of which are cutouts of the NaCl type. For SnSe contents between x = 5 and x = 0.5, several new phases were discovered. Next to, for example, Sn 4 Bi 2 Se 7 ( x = 4) in the NaCl structure type and SnBi 4 Se 7 ( x = 0.5) in the layered defect GeSb 2 Te 4 structure type, there are at least four compounds (0.8 ≤ x ≤ 3) with lillianite-like structures built up from distorted NaCl-type slabs (L4,4-type Sn 2.22 Bi 2.52 Se 6 , L4,5-type Sn 9.52 Bi 10.96 Se 26 , L4,7-type Sn 11.49 Bi 12.39 Se 30 , and L7,7-type Sn 3.6 Bi 3.6 Se 9 ). For two of them (L4,7 and L7,7), the cation distributions were determined by resonant X-ray scattering, which also confirmed the presence of significant amounts of cation vacancies. Thermoelectric figures of merit ZT range from 0.04 for Sn 4 Bi 2 Se 7 to 0.2 for layered SnBi 4 Se 7 ; this is similar to that of the related compounds SnBi 2 Te 4 or PbBi 2 Te 4 . Compounds of the lillianite series exhibit rather low thermal conductivities (∼0.75 W/mK for maximal ZT). More than other "sulfosalts", compounds in the pseudobinary system SnSe-Bi 2 Se 3 adapt to changes in the cation-anion ratio by copying structure types of compounds containing lighter or heavier homologues of Sn, Bi, or Se and can incorporate significant amounts of vacancies. Thus, (SnSe) x Bi 2 Se 3 is a multipurpose model system with vast possibilities for substitutional and structural modification aiming at the optimization of thermoelectric or other properties.

The complexation properties of two novel C5-substituted adamantanediazirines within the resorcin[4]arene-based cavitand 4 were investigated in DMSO-d(6), revealing that binding is up to 1.4 kcal/mol stronger for halogenated adamantanediazirines when compared with the unsubstituted species. The thermal behavior of 5-bromo-2-aziadamantane (3) was investigated by DSC analysis as the first representative of the adamantanediazirine family in the neat solid state, as well as encapsulated within the aromatic cavity of cavitand 4. In the solid phase, the reactions of photolytically or thermolytically generated 5-bromo-2-adamantanylidene (11) can be controlled by complexation within cavitand 4.