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Luminescent rhenium complexes continue to be the focus of growing scientific interest for catalytic, diagnostic and therapeutic applications, with emphasis on the development of their photophysical and photochemical properties. In this short review, we explore such properties with a focus on the biological applications of the molecules. We discuss the importance of the ligand choice to the contribution and their involvement towards the most significant electronic transitions of the metal species and what strategies are used to exploit the potential of the molecules in medicinal applications. We begin by detailing the photophysics of the molecules; we then describe the three most common photoreactions of rhenium complexes as photosensitizers in H2 production, photocatalysts in CO2 reduction and photochemical ligand substitution. In the last part, we describe their applications as luminescent cellular probes and how the photochemical ligand substitution is utilized in the development of photoactive carbon monoxide releasing molecules as anticancer and antimicrobial agents.

The important role of the Balkans in the origin and development of metallurgy is well established with respect to copper. In addition, Aleksandar Durman, in his 1997 paper ?Tin in South-eastern Europe??, essentially initiated studies into the role of the Balkans in Europe?s Bronze Age tin economy. He identified six geologically favourable sites for tin mineralisation and associated fluvial placer deposits in the former Yugoslavian republics, and suggested that these may have added to the tin supply of the region. The viability of two of these sites has been confirmed (Mt Cer and Bukulja, Serbia) but the exploitation potential for the other locations has remained untested. River gravels from these four sites (Motajica and Prosara in Bosnia and Herzegovina; Bujanovac in Serbia; Ograzden in North Macedonia) were obtained by stream sluicing and panning. The sites of Prosara and Bujanovac were found to be barren with respect to cassiterite (SnO2). Streams flowing from Motajica and Ograzden were both found to contain cassiterite, but in amounts several orders of magnitude less than at Mt Cer and Bukulja. Although it is possible that minor tin recovery occurred at Motajica and Ograzden, it is unlikely that they could have contributed meaningfully to regional tin trade. This is supported by the fact that the isotopic signature (?124Sn) of cassiterite from Motajica is highly enriched in light isotopes of tin compared to that associated with Late Bronze Age artefacts of the region.

Relevance of the work is the development of new methods for rapid extraction (determination) of ore bodies in the underground mine of the field directly. Measurements were carried out both on specially prepared samples in the form of cubes of the same size, and under conditions of natural occurrence. Purpose of the work is to study the magnetic susceptibility and electrical resistivity of the main host rocks and the ore complex (emerald-bearing glimmerites and quartz-plagioclase veins with beryl) in the most famous Ural emerald-beryllium deposit, the Mariinsky deposit. Methodology of research. In order to study the magnetic properties of typical rocks and ore bodies of the Mariinsky deposit, the PIMV-M field magnetic susceptibility meter with a measurement range of 1 · 10–5… 1 SI units was used in the underground mine directly. The relative measurement error does not exceed ± 10% in the range of 10–4 ... 1 SI units. The measurement was carried out by applying the flat surface of the measuring transducer to the bottomhole wall in a lithologically homogeneous section with subsequent measurement and recording of the obtained value in the field document. To study the electrical resistivity, standard samples in the form of cubes of 24 × 24 × 24 mm were used; their composition was investigated with the help of binocular enhancer MBS-10. The measurements were carried out along three axes since almost all samples have anisotropy. The teraohmmeter E6-13A was used for working. Results. The data on the magnetic susceptibility and electrical resistance of the main host rocks and the ore complex (emerald-bearing glimmerites and quartz-plagioclase veins with beryl) from the Mariinsky deposit are presented. All data are adjusted with the petrographic characteristics of rocks. Conclusions. Possibility in principle is shown for creating a new express-method for isolating quick micaceous veins in wells and mine faces with the simultaneous measurement of magnetic susceptibility and electrical resistance of rocks during mining operations in an underground mine

Landforms in different environmental ecosystems are formed through selective erosion and transport mechanisms by wind and water. To understand their development, biochemical composition, and effect on neighbouring ecosystems, it is essential to better understand the forming processes and to be able to monitor the behaviour and transport of particles through the landscape. Conventional methods to track and differentiate between organic and inorganic particles usually involve extensive sampling campaigns that disturb the processes themselves. Therefore, this study aimed to prove that the method of photogrammetry, which is non-contact and non-invasive, is able to quantify erosion rates and can also be used to differentiate between organic and inorganic material. To prove this concept, a bottom-up experimental rainfall simulation set-up was conducted with sieved sand substrates of very narrow particle size distribution and biochar under highly controlled conditions. By using two-dimensional index and reflectance maps of the surface computed with the software Pix4D, the erosion of biochar was estimated and compared to the actual erosion amount that was transported along the plot. The results show that photogrammetry has the potential to distinguish between a sandy substrate and biochar. An approximate decrease of 5 % in biochar on the plot surfaces was detected in three out of four rainfall experiments within the first 30 s. After these 30 s, the quality of detection was significantly reduced due to shadow effects, which were falsely classified as biochar as well. For future investigations on this topic, it will be necessary to improve the lighting of the plot and the post-processing of the images to reduce the error caused by shadows. Additional approaches that should be taken into account for further test experiments are the full exclusion of external light, which means working in the dark, and the use of hyperspectral cameras to detect different carbon types.

Cobalt intoxication is a rare cause of toxic opticopathy, and may be caused by metal endoprostheses. Since its clinical appearance is unspecific and the incidence low, diagnosis is challenging. Due to the dramatic consequences of delayed treatment, cobalt intoxication should be considered as a rare differential diagnosis of bilateral loss of vision in patients with appropriate history.Die Kobaltintoxikation ist eine seltene Ursache einer toxischen Optikopathie, die durch Metallendoprothesen ausgelöst werden kann. Die Diagnosestellung ist aufgrund des unspezifischen klinischen Erscheinungsbildes und der geringen Inzidenz schwierig. In Anbetracht der dramatischen Folgen einer verspäteten Therapie sollte eine Kobaltvergiftung als eine seltene Differenzialdiagnose bei Patienten mit beidseitiger Visusminderung und entsprechender Anamnese (i. e. Hüft-TEP in der Vorgeschichte) in Betracht gezogen werden.

Gemischtleitende Perowskite können genutzt werden, um Sauerstoff hochselektiv von anderen Gasen abzutrennen. Über Nassspinnen lassen sich daraus einfach skalierbar Hohlfasermembranen fertigen, die durch ihre dünne Wand und die hohe spezifische Oberfläche eine sehr hohe Sauerstoffpermeanz zeigen. Diese Membranen können in einem Plasma-Membranreaktor eingesetzt werden, um nach der Spaltung von CO2 in CO und O2 den Sauerstoff abzutrennen und dadurch eine Rückreaktion zu CO2 zu vermeiden.

Due to the fact that strontium (Sr) is not involved in the scope of supervision of drinking water in China, the Sr concentration in public drinking water and its related health risks have been neglected for a long time. In this research, public drinking water samples were collected from 314 cities across the country to reveal the concentration and spatial distribution of Sr in public drinking water. In addition, the Monte Carlo method (a statistical simulation method) was applied to evaluate the Sr intake from drinking water and human health risks among different age groups and different regions. As shown in the results, the Sr was in the concentration range of 0.005–3.11 mg/L with a mean value of 0.360 mg/L. There were significant differences in the Sr concentration in different regions; in general, it was high in the north and low in the south. The Sr intakes of infants, children, teens, and adults from drinking water were 0.273, 0.503, 0.633, and 0.784 mg/day, respectively. There was a significant positive correlation between Sr concentration in drinking water and bone mineral density (BMD) in the elderly. Especially, the correlation coefficients (r) between Sr concentration and the BMD of the elderly whose age fell in the range of 60–70 years were 0.692 (male) and 0.483 (female). In addition, the Sr concentration in drinking water was positively correlated with the incidence of children’s rickets (r = 0.411), while the Ca/Br ratio was negatively correlated with the incidence of children’s rickets (r = − 0.410). According to the health risk assessment, among people of different ages, infants’ hazard index (HI) value was the highest. The mean value and 95th percentile value were 0.066 and 0.247. Non-carcinogenic risk of Sr through drinking water among different people in different regions was less than 1, which meant no significant damage to human health. This study is the first time to systematically investigate Sr in public drinking water across the whole country. More importantly, the conclusions can be applied to risk control and management of public drinking water. Supplementary Information The online version contains supplementary material available at 10.1007/s11356-021-12378-y.

Relevance of the topic is due to concern of modern civilized society about the negative impact on the ecology of man-made mineral formations of the mining activity. Technogenic ores are represented by sludges, which are removed by groundwater from abandoned pits and rock dumps. They are deposited in surface watercourse and serve as a source of environmental disasters. They overfill natural and artificial sedimentation basin, and the mine waters carrying them threaten to increase acidity in protected reservoirs that serve as a source for drinking water for big cities. At the same time, in recent years, the industrial value of these sludges has been determined, and the technology has been developed for extracting non-ferrous metals and useful associated components from them. It is revealing that this ore sludge occur directly in alluvial and deluvial deposits of river valleys and ponds, which are also of industrial interest as a source of surface gold and industrial minerals – sand gravel mixes. The need for the extraction of large volumes of the latter is particularly relevant, since an extensive construction program is planned and implemented here. The purpose of this paper is to attract attention of business and the public to an economically advantageous project for the development of manmade copper-zinc ores from the abandoned pits of the Urals with a simultaneous solution of environmental problems. Methodology. The work was done by the authors using the results of their own research and materials in collaboration with the team of Nedra group Ltd. The result of the work. The authors have shown the presence of technogenic copper-zinc deposit within the territory of the Degtyarsky pit and predicted gold-bearing placers in addition to it. Conclusions. The main task of the study in the territory of the Degtyarsky pit is granting the licenses for the sites of Istok and Elchyovka; the estimated cost of engineering design and geological exploration with an evaluation of reserves of non-ferrous, noble metals and associated raw materials in sludge and alluvium-deluvium, as well as with the solution of environmental problems, ranges from 50–60 to 80 million rubles.

A number of 42 Greek coins (most of them issued and/ or circulated at Histria during the autonomous period of the city and several issued by Histria during Roman times) were found during the 2013‐ 2016 archaeological campaigns conducted in the Acropolis Centre‐ South Sector. The coins, made of copper and copper‐ based alloys, were subject to a non‐ invasive compositional analysis using a portable X‐ Ray Fluorescence (XRF) spectrometer, in order to determine trends and technological choices in the coinage production. The composition of these items was compared to that characterising a batch of coins found at Histria during older excavations., Un număr de 42 de monede greceşti (cele mai multe emise şi/ sau în circulaţie la Histria de‐ a lungul perioadei autonome, precum şi câteva emise de Histria de‐ a lungul perioadei romane) au fost descoperite în cursul campaniilor arheologice 2013‐ 2016 din Sectorul Acropolă Centru‐ Sud de la Histria. Monedele, realizate din cupru şi aliaje ale cuprului, au constituit subiectul unei analize compoziţionale non‐ destructive utilizând un spectrometru cu fluorescenţă de raze X (XRF) portabil, cu scopul de a determina trenduri şi alegeri tehnologice în producerea monedelor. Compoziţia acestor piese a fost comparată cu cea a unui lot de monede provenind din săpături mai vechi efectuate la Histria., Ţârlea Alexandra, Georgescu Migdonia, Vîlcu Aurel. The compositional analysis of copper and bronze Greek coins found at Histria (Acropolis Centre-South Sector) using a portable X-Ray fluorescence spectrometer. In: Materiale şi cercetãri arheologice (Serie nouã), N°14 2018. pp. 197-209.

The relevance of the work is conditioned by the need for a more complete study of the mineralogy of rare-metal granite pegmatites of the Lipovskoye vein field. The purpose of the study is to describe the findings of native metals (gold, silver, copper, lead, bismuth and tungsten) in granite pegmatites of the Lipovskoye vein field. Research methodology. Detailed study of chemical composition, morphology and relationships of native metals with associated minerals. For this study we have chosen samples from the three types of granitic pegmatites – classical quartz-feldspar (mostly intragranitic), desilicated (apogranite plagioclasite) and contaminated lithium-bearing. Results. The paper describes native metals (gold, silver, copper, lead, bismuth and tungsten), which we have found in rare-metal pegmatites of the Lipovskoye vein field. The discovery of the native metals is the first on this facility. The microprobe analysis of such native metals as gold and silver showed the variability of their chemical composition from the type of pegmatite in which they are present. The formation of native lead should be logically linked to the destruction and recrystallization of high uranium thin rims of zircons. The formation of bismuth and tungsten may have occurred during recrystallization of accessory tantalumniobates. Summary. The finding of the native metals in granitic pegmatites is quite explainable. This is because these core rocks are formed in the post-magmatic stage of the silicate crystallization intrusions and they can contain typomorphic rocks for these metals. The absence of mineral concentrators (sulfides) in pegmatites clearly explains the small size and high dispersion of metals.

This paper presents results from a comparison of wholewood and cellulose carbon and oxygen isotope ratios for four UK tree species. These species occur within the historic buildings archive as both primary and supplementary construction materials and have been used to reconstruct the climate of the past. New advances in the application of stable isotopes have widened the scope of the isotope approach, but require the time-consuming purification of cellulose. Comparison of the oxygen and carbon isotope signals preserved in the wood and cellulose components confirms and builds upon previous research in this field and provides additional insight into the covariance of these two sample types between species, an V prispevku so predstavljeni rezultati primerjave analize stabilnih izotopov ogljika in kisika v lesu in celulozi drevesnih branik štirih najpogostejših drevesnih vrst v Veliki Britaniji: pravega kostanja, bukve, doba in rdečega bora. Les teh drevesnih vrst pogosto najdemo tudi v različnih lesenih konstrukcijah, kar nam, v kombinaciji z lesom iz živih dreves, omogoča rekonstrukcijo klime v čas pred instrumentalnimi meritvami. Razvoj detekcijskih tehnik za stabilne izotope je omogočil uporabo stabilnih izotopov tudi tam, kjer to tradicionalno ni bilo možno (npr. za datiranje starih stavb), še vedno pa je glavna ovira za širšo uporabo teh metod zahtevna in zamudna ekstrakcija celuloze iz posameznih lesnih branik. Primerjava stabilnih izotopov kisika in ogljika v lesu in (alfa)-celulozi je potrdila dosedanje vedenje in dodala nova spoznanja o primerljivosti razmerij stabilnih izotopov, analiziranih v lesu in celulozi, kar nam bi lahko omogočilo izločitev zamudne tehnike ekstrakcije celuloze in neposredno uporabo homogeniziranega lesa b

Chemie - Ingenieur - Technik : CIT (2020). doi:10.1002/cite.201900148, Published by Wiley-VCH Verl., Weinheim

Significant progress is going on in the development of non-fossil based alternative fuels which are designed to be sustainable, have potential to substitute (fully or partially) the fossil-based fuels and importantly are targeted to reduce emissions. Though soot emission characteristics has not been focus of fuel certification process yet, due to growing environmental concerns it is important to consider this aspect in the fuel design and understand its emission patterns. It is known that soot formation in combustion is linked to the degree of branching, degree of unsaturation or the degree of cyclization of a fuel molecule. This information is used to extract soot emission properties of complex real fuel mixtures. To do so, we use the definition of hydrogen deficiency (HD) which gives information on the number of double bonds or cyclic structures present in a fuel. With the help of one measured emission property, the same property of different fuels is predicted using HD. This way, we obtain a relative assessment of fuels’ sooting tendency compared to other known fuels. In this work, soot emission pattern of six jet fuels (reference fuels and synthetic fuels) is predicted based on HD and compared them with the recent ground-test measurements of V2527-A5 engine of an Airbus A320. In addition, two more test cases are provided: aviation fuels and diesel fuels, to predict sooting tendency using HD to support our concept. The prediction of the sooting propensity based on HD was found in excellent agreement with the measurements.

Metal borohydrides have been studied since the beginning of this century as potential hydrogen storage materials due to their high gravimetric hydrogen content. Many new compounds have been synthesized and characterized, however to date the main problem are the kinetics of dehydrogenation and rehydrogenation. In this review we address thermodynamical and chemical properties of boron hydrogen compounds which come into play for hydrogen storage and which must be considered in the search for efficient catalysts. More recently, closo and nido hydridoborate and related closo hydridocarborate compounds have been identified as good ionic conductors for all-solid-state lithium or sodium batteries. The properties of these fascinating and very promising compounds for battery applications are illustrated with recent literature results.

Damage-tolerant ceramic matrix composites (CMC) are prone to high temperature applications under severe environmental conditions and usually utilize carbon or ceramic fibres (e.g. SiC) as reinforcements of ceramic matrices with inherent low elongation to break compared to common metals. However, CMC reveal an elongation to break and stiffness similar to the ceramic matrices, and thus need a fibre coating in order to improve the elongation to break length and thus to achieve damage tolerance of the composite. In addition, such fibers often expose a low ductility during failure. As a consequence, design criteria for components of such CMC materials are limited by the low strain of failure. In order to overcome this problem, we follow the idea of a reinforcement concept of a ceramic matrix reinforced by refractory metal fibres to reach pseudo ductile behaviour during failure. Tungsten (W) and molybdenum (Mo) fibers were chosen as reinforcement in SiCN CMC manufactured by polymer infiltration and pyrolysis process. These fibres are commercially available since they are widespread used in light bulbs, etc. , and possess an intrinsic higher elongation to break, compared to ceramic fibres, as well as high stiffness even at high temperatures. W/SiCN and Mo/SiCN composites were manufactured via filament winding and resin transfer moulding of commercially available polysilazanes, pyrolysed and re-densified by multiple reinfiltration and pyrolysis steps. These composites were investigated with respect to microstructure, flexural and tensile strength. Single fibre strengths for W and Mo were investigated and compared to the strength of the composites. Tensile strengths of 206 and 156 MPa as well as bending strengths of 427 and 312 MPa were achieved for W/SiCN and Mo/SiCN composites, respectively. W fibre became brittle across the entire cross section, while the Mo fibre showed a superficial, brittle reaction zone but kept ductile on the inside.

Summary: Over 18 months long measurements of outdoor radon in three areas (a total of 69 locations) in England were conducted between years 2015 and 2017 using PADC based passive nuclear track detectors. Special measurement equipment and protocols to counteract unfavourable weather conditions have been designed, developed and optimised for the low level radon concentration. Keywords: Outdoor radon, PADC, Baseline monitoring

Photochemical reactions are often presented as intrinsically environmentally friendly ('green'). This may be indeed the case, but only in particular circumstances. This short essay comments on various aspects of the greenness of photochemical reactions, both in a historical (when only mercury-based hard UV light sources were available) and a current (with the recent introduction of LED technology and photoredox catalysis) perspective.

The sorption experiments with the five rock samples drilled in the deep-well in the exocontact zone of Nizhnekansky granitoid massif (EZNGM) in the range of depth 166–476 m were carried out. The distribution of radium was studied. The radiograms of radionuclide sorption were obtained by digital autoradiography. Heterogeneous sorption of radium was demonstrated by digital radiography and phases with higher sorption ability were revealed. The technique for the treatment of radiograms with the help of ImageJ program for obtaining quantitative parameters of radionuclides distribution in the granite-gneiss rock samples was developed. Relative sorption efficiency of different mineral phases of the rock samples of Eniseysky area (EZNGM) toward radium is presented in the paper. Keywords: Final isolation of HLW, Radium sorption, Granitoid samples, Digital autoradiography, Imaging Plate

Abstract: Nanorattles and hollow nanocontainers have unique properties related to the presence of a void space inside the shell, which has been shown to improve the properties of materials for e.g. catalysis, drug release, sensor materials or lithium ion batteries. This article summarizes our recent progress in the synthesis of hollow silica, titania and ceria nanorattles and nanocontainers, eventually encapsulating AgNPs as cargo and highlights their potential applications in catalysis and biomedicine.

Summary This paper focuses on corrosion characteristics of cast and forged aluminium 6061 based composites reinforced with TiB 2 particles. Composites were synthesised by in situ technique using potassium hexafluorotitanate salt (K 2 TiF 6 ) and potassium tetrafluroborate (KBF 4 ) halide salts by stir casting route at a temperature of 850 °C. Cast aluminium alloy and its in situ composites were subjected to open die drop forging at a temperature of 500 °C. Both cast and forged alloy 6061 and in situ composites were then subjected to microstructure studies, salt spray test. Salt spray test was conducted as per ASTM B117 standard test procedure using 5% sodium chloride test solution. Result reveals that, forged alloy and its in situ composites exhibited improved corrosion resistance compared to cast ones.

Here we describe a unique microbial biotechnology for simultaneous bioremediation and biomining of twelve ionic metals overcoming the obstacles of multimetal toxicity to microbes. After a thorough search of key microorganisms in microbiomes of many sulfidic springs in Bavaria (Germany) over an area of 200 km2, we found three new strains EH8, EH10 and EH11 of Mucor hiemalis physiologically compatible and capable of multimetal-remediation and enrichment. We combined the multimetal-resistance, hyper-accumulation and elicitation power of EH8, EH10 and EH11 to develop a novel biotechnology for simultaneous removal, fractionation and enrichment of metal ions. As a first step we showed the intracellular fixing and deposition of mercury as nanospheres in EH8’s sporangiospores. Scanning Electron Microscopy-Energy-Dispersive X-Ray analysis revealed binding and precipitation of other applied metal ions as spherical nano-particles (~50–100 nm) at the outer electro-negative cellwall-surface of EH8, EH10 and EH11 sporangiospores. Microbiomes, germinated spores and dead insoluble cellwalls of these strains removed >81–99% of applied Al, Cd, Co, Cr, Cu, Hg, Ni, Pb, U, and Zn simultaneously and furthermore enriched precious Ag, Au and Ti from water all within 48 h, demonstrating the potential of new biotechnologies for safe-guarding our environment from metal pollution and concentrating precious diluted, ionic metals.

In this paper a hydrogen-based air-conditioning unit, which can also function as range extender for electric vehicles, is studied. This hydrogen A/C-unit utilizes the endothermic reaction of hydrogen desorption from metal hydrides to generate a cooling effect. Within DLR’s Next Generation Car project a prototype system was developed and characterized on a test bench. This system represents a world’s first proof of concept, where two metal hydride reactors are coupled to a fuel cell to establish a process which provides cooling power without any electrical power input. The measured cooling power is directly coupled to the hydrogen mass flow taken from the reactors, thus being indirectly linked to the fuel cells electrical power output. A maximal heat flow of 0.72 kW was detected at 5 kW electric fuel cell power. The paper concludes with the discussion of an appropriate vehicle integration concept for this innovative technology.

Algal-derived dissolved organic matter (ADOM) originating from lysed Microcystis aeruginosa cells was investigated as precursor material to form disinfection by-products upon disinfection with free chlorine. Non-targeted ultrahigh resolution 12 T negative mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) revealed high molecular diversity in solid-phase extracted and ionizable components of Microcystis aeruginosa ADOM. The toxin microcystin LR was effectively degraded by free chlorine, which was expected. However, we found a high diversity of disinfection by-products associated with the addition of free chlorine to the water-soluble and solid-phase extractable fraction of ADOM and of double-bond moieties in abundant and known unsaturated fatty acids. Aromatic DOM precursors were absent from known metabolites of Microcystis aeruginosa and no evidence for aromatic disinfection by-products (DBPs) was found, despite N-containing compounds. A large diversification of N-containing molecular formulas was observed after chlorination, which seems indicative for the breakdown and oxidation of larger peptides. Additionally, a diverse group of N-compounds with presumed chloramine functional groups was observed. This study highlights the importance to evaluate ADOM and its ability to form different DBPs when compared to allochthonous or terrestrially-derived DOM. (C) 2019 The Author(s). Published by Elsevier Ltd.

Herein, a two-step procedure for the preparation of oxygenated ortho-methylbenzaldehyde derivatives, starting from commercially available bromoarenes, is described. The synthesis features the simultaneous and highly regioselective installation of both the methyl and the formyl group onto the benzene core via benzyne [2+2] cycloadditions with acetaldehyde lithium enolate to give the corresponding benzocyclobutenols in high yields. Bond-selective ring opening of the benzocyclobutenols under basic conditions in methanol delivers the title compounds.

Catalytic processes involving cooperativity have seen tremendous progress in recent years and impressive new synthetic methodologies have been developed. Inspired by the cooperative heterolytic H2 splitting in [NiFe] hydrogenases, Ohki and Tatsumi designed cationic ruthenium thiolate complexes with a tethered sulfur ligand. Over the last decade, we have demonstrated the facile activation of main-group hydrides such as hydrosilanes, hydroboranes, DIBAL–H, and hydrostannanes by the Ru–S bond in Ohki–Tatsumi complexes. This account illustrates these E–H bond activations and highlights selected catalytic applications, particularly dehydrocouplings, of the generated main-group electrophiles.

Crack deflection is studied for the aluminum alloys AA2024-T351 and AA5028-H116 under biaxial fatigue loading. With cruciform specimens that have a testing area of about 420 × 420 mm2 a fatigue crack was subjected to nominal biaxiality ratios between 1.0 and 3.0. Consequently, the crack is subjected to different magnitudes of T-stress. Finite element simulations of the growing crack revealed that the crack path is not significantly influenced by the T-stress but the T-stress predicts whether the crack path remains stable. If at least two crack paths are basically possible the crack will kink for positive T-stresses and remain stable for negative T-stresses. Furthermore, small spikes with strain concentrations along the crack path are identified with digital image correlation which might cause crack deflection in this case.

Zusammenfassung: Es wird ein Fall vorgestellt, der auf den ersten Blick an spektakuläre Arsenmorde der Vergangenheit anzuknüpfen scheint. Im Rahmen von Scheidungsstreitigkeiten zwischen einem 70-jährigen Mann und seiner knapp 30Jahre jüngeren Frau war es beim Betroffenen zu Symptomen einer Arsenvergiftung gekommen. Nach dem unerwarteten Tod seines Hundes hatte der Mann seinen Hausarzt aufgesucht, der bei einer Blutuntersuchung einen erhöhten Arsenspiegel feststellte. Bei chemisch-toxikologischen Analysen von Probenmaterial, das im Rahmen rechtsmedizinischer Untersuchungen der Betroffenen sowie einer Exhumierung des Hundes gewonnen wurde, fanden sich bei dem Mann und seiner Frau auffällig erhöhte Arsenspiegel. Die vorliegende Kasuistik unterstreicht eindrücklich die Wichtigkeit der Arsenspezifizierung in einem qualifizierten Labor im Fall einer erhöhten Arsenkonzentration in Probenmaterial

Templated reactions proceed by bringing reagents in close proximity through their interaction with a template thus raising their effective concentrations. Templated reactions empower chemists to perform reactions at low concentrations in complex environments. Herein, we discuss our work on templated reactions leveraged on ruthenium photocatalysis. Over the past five years, we have used this reaction to uncage reporter molecules and sense or image nucleic acids or proteins of interest. The ruthenium photocatalysis chemistry has proven to be extremely robust and compatible with complex biological environments.

N2 is a cheap and widely available but very unreactive molecule. Notably, the only industrial process for the conversion of dinitrogen is the Haber-Bosch process to form ammonia, but under very harsh conditions (high temperature and pressure). Here, we review our recent research leading to the reduction of dinitrogen by four electrons, under ambient conditions by a uranium(III) bridging nitride, K3 U-N-U, where two uranium(III) cations are linked by a nitride group and a flexible metal–ligand scaffold. We also show that the bound dinitrogen can be further functionalized under mild conditions: the addition of acid, hydrogen and protons or carbon monoxide to the uranium hydrazido complex yields to the cleavage of the N-N single bond and to the formation of new N–H and N–C bonds.

Herein we present the first example of a three-component dicarbofunctionalization of olefins under reductive conditions. Our strategy takes advantage of nickel catalysis to add aryl and alkyl groups across the double bond with remarkable selectivity. The reaction shows broad functional group compatibility and more importantly, it proves to be general in terms of the alkenes that can be functionalized compared to previous dicarbofunctionalization methods. Initial control experiments reveal different activation modes for both electrophiles and the involvement of alkyl radicals throughout the reaction.

The chiral iron(II) hydride complex [FeH(CNCEt3)(1a)](BF4) (3, 1a is a chiral macrocycle with an (NH)2P2 donor set) catalyzes the base-free transfer hydrogenation (ATH) of prochiral ketones and the hemireduction of benzils to the corresponding benzoins using i PrOH as hydrogen donor. Ketones give the same excellent enantio-selectivity (up to 99% ee) as the parent catalyst [Fe(CNCEt3)2(1a)](BF4)2 (2), which is only active upon treatment with NaOtBu. Benzoins, whose labile stereocenter is known to undergo racemization under basic conditions, are formed in up to 83% isolated yield with enantioselectivity as high as 95%., Chimia, 72 (4), ISSN:0009-4293

Summary The present phenomenon, i.e. enhancement of mass transfer coefficient in liquid–liquid extraction operation is a complex one and it cannot be reasoned out by any logic based model, so it is find out by experimental data based model. The present investigation is focused on the behaviour of nanofluid in the liquid–liquid extraction process. The chemical system of toluene–acetic acid–water was used, and nanofluids containing 0.1%, 0.2% and 0.3% (V/V) of zinc oxide nanoparticles of size 48.79 nm synthesised by chemical precipitation method. Maximum enhancements in the rate of mass transfer of were achieved using about 0.3 wt% zinc oxide based nanofluids; however, a decreasing variation was observed at higher concentrations. The effect of nonionic surfactants Rokanol K7 (500 ppm) on mass transfer of the liquid–liquid extraction process was also investigated and it was observed that the mass transfer coefficient increases rapidly with surfactants under a varying speed of agitation but deteriorates at high concentration. The formulation of approximate generalised experimental data based model has been developed followed by interpretation and the quantitative analysis of the model. For the aim of modelling, the experimental results obtained from liquid–liquid extraction were validated with mathematical modelling for calculation of reliability of model.

Summary Among different shape memory alloys, copper (Cu) based alloys were the most favourable alloys, because of their attaining price and good characteristic properties. In this present work different weight compositions of Cu–Al–Be–Mn shape memory alloys are considered and are in the range of 10–14 wt% of aluminium (Al), 0.4–0.5 wt% of beryllium (Be) and 0.3–0.4 wt% of manganese (Mn) and these alloys were synthesized by ingot metallurgy, which exhibits β-phase at higher temperatures, also demonstrates a shape memory effect (SME) after quenching to room temperature. The Be, Mn and Al content was varied in different sets to study the shape memory effect and damping behaviour of the alloys by using differential scanning calorimetry and dynamic mechanical analyzer respectively. These alloys exhibit higher damping or internal friction in the martensitic condition and internal friction or damping peak in the transition zone.

The paper focuses on the performance and aging behavior of lithium nickel cobalt manganese oxide commercial standard material (NCM-111) which is improved with a post synthesis process in order to enhance the cathode active material of lithium-ion pouch cells regarding their capacity and cyclic stability. The aging behavior of the cells is analyzed with electrochemical impedance spectroscopy (EIS) during long-term electrochemical load cycling tests based on the Common Artemis Driving Cycle (CADC). Additionally, post-mortem investigations using scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed. The results demonstrate that post-processing of electrode active material is an effective tool to improve the properties of lithium-ion electrode materials, especially regarding high energy applications and lifetime optimization. The paper bridges the gap between lithium-ion battery electrode material development and the necessary cell testing under automotive relevant conditions which is important for the evaluation of new lithium-ion battery materials for automotive applications.

Electroceramic support materials can help reducing the noble-metal loading of iridium in the membrane electrodes assembly (MEA) of proton exchange membrane (PEM) electrolyzers. Highly active anodes containing Ir-black catalyst and submicronic Ti4O7 are manufactured through screen printing technique. Several vehicle solvents, including ethane-1,2-diol; propane-1,2-diol and cyclohexanol are investigated. Suitable functional anodic layer with iridium loading as low as 0.4 mg cm−2 is obtained. Surface properties of the deposited layers are investigated by atomic force microscopy (AFM). The most homogeneous coating with the highest electronic conductivity is obtained using cyclohexanol. Tests in PEM electrolyzer operating at 1.7 V and 40 °C demonstrate that the CCM with anode coated with cyclohexanol presents a 1.5-fold higher Ir-mass activity than that of the commercial CCM.

The preparation, structural characterization, luminescence, and catalytic activity of three palladium(II) complexes bearing imino phenoxide ligands are reported. The X-ray studies revealed that the complexes are mononuclear with palladium centres coordinated in a square-planar coordination environment. Two of the complexes are emissive in solution at room temperature. The catalytic activities towards the ring-opening polymerization of rac-lactide (rac-LA) were tested. Polymers with moderate molecular weights and relatively broad dispersity (Ð) were obtained. Kinetic studies revealed that the polymerization followed first-order kinetics. Graphical abstract Electronic supplementary material The online version of this article (10.1007/s00706-017-2119-1) contains supplementary material, which is available to authorized users.

Variable conductance heat pipes (VCHPs) are the main part of the MASCOT (mobile asteroid surface SCOuT) lander thermal control system (TCS). They provide variable conductivity by utilizing the heat transfer limitations. This allows the heat pipes to act as thermal switches without additional constructive elements, thus leveraging the simple and compact design of conventional heat pipes. Two cylindrical methanol–copper heat pipes with shell length of 0.482 m and 0.438 m and external diameter of 0.006 m, having copper discrete metal fiber wick and copper shell were constructed and verified in the temperature range between −75 and +60 °C. The purpose is to apply this design into the MASCOT TCS and to investigate the heat pipes' regulative characteristics and heat transfer limitations. VCHPs show a change of thermal resistivity from 70 K/W at a heat sink temperature of −60 °C, to 0.8 K/W at a heat sink temperature of +60 °C; with an obtained maximal heat transfer rate of 5 W and 16 W, respectively. It is found that the switching effect of the heat pipes is governed by the sonic velocity limitation, the saturation vapor pressure of the working fluid, and the maximal capillary pressure of the wick. The operation of the heat pipes as the part of the TCS has confirmed their variable thermal properties.

Population-based and interventional studies have shown that elevated zinc levels can reduce the progression to advanced age-related macular degeneration. The objective of this study was to assess whether elevated extra cellular zinc has a direct effect on retinal pigment epithelial cells (RPE), by examining the phenotype and molecular characteristics of increased extracellular zinc on human primary RPE cells. Monolayers of human foetal primary RPE cells were grown on culture inserts and maintained in medium supplemented with increasing total concentrations of zinc (0, 75, 100, 125 and 150 mu M) for up to 4 weeks. Changes in cell viability and differentiation as well as expression and secretion of proteins were investigated. RPE cells developed a confluent monolayer with cobblestone morphology and transepithelial resistance (TER) > 200 Omega*cm(2) within 4 weeks. There was a zinc concentration-dependent increase in TER and pigmentation, with the largest effects being achieved by the addition of 125 mu M zinc to the culture medium, corresponding to 3.4 nM available (free) zinc levels. The cells responded to addition of zinc by significantly increasing the expression of Retinoid Isomerohydrolase (RPE65) gene; cell pigmentation; Premelanosome Protein (PMEL17) immunoreactivity; and secretion of proteins including Apolipoprotein E (APOE), Complement Factor H (CFH), and High-Temperature Requirement A Serine Peptidase 1 (HTRA1) without an effect on cell viability. This study shows that elevated extracellular zinc levels have a significant and direct effect on differentiation and function of the RPE cells in culture, which may explain, at least in part, the positive effects seen in clinical settings. The results also highlight that determining and controlling of available, as opposed to total added, zinc will be essential to be able to compare results obtained in different laboratories.

Biomedical Engineering / Biomedizinische Technik, 41 (s1), ISSN:0013-5585, ISSN:1862-278X

Metal-air batteries are among the most promising next-generation energy storage devices. Relying on abundant materials and offering high energy densities, potential applications lie in the fields of electro-mobility, portable electronics, and stationary grid applications. Now, research on secondary zinc-air batteries is revived, which are commercialized as primary hearing aid batteries. One of the main obstacles for making zinc-air batteries rechargeable is their poor lifetime due to the degradation of alkaline electrolyte in contact with atmospheric carbon dioxide. In this article, we present a continuum theory of a commercial Varta PowerOne button cell. Our model contains dissolution of zinc and nucleation and growth of zinc oxide in the anode, thermodynamically consistent electrolyte transport in porous media, and multi-phase coexistance in the gas diffusion electrode. We perform electrochemical measurements and validate our model. Excellent agreement between theory and experiment is found and novel insights into the role of zinc oxide nucleation and growth and carbon dioxide dissolution for discharge and lifetime is presented. We demonstrate the implications of our work for the development of rechargeable zinc-air batteries., 16 pages, 8 figures, Supplementary Information uploaded as ancillary file

We have investigated the influence of substituting bismuth for lead in lead telluride. The material was nanostructured by mechanical alloying and compacted via short-term sintering or hot pressing. Synthesis of samples with substitution up to 6 at.% bismuth was carried out twice to ensure reproducibility. All relevant thermoelectric transport parameters were measured in a wide temperature range from 123 K or 173 K to 773 K. Two different techniques for measuring the electrical conductivity and Seebeck coefficient were used, one at low and the other at high temperature. Higher bismuth content of 4 at.% to 6 at.% was found to result in the best thermoelectric properties, with maximum ZT value of about 0.7 at 723 K for 4.0 at.% bismuth. The structure was examined in detail via x-ray diffraction analysis, Raman spectroscopy, and transmission electron microscopy. A key feature of the microstructure was the inhomogeneous distribution of bismuth in the lead telluride matrix and the occurrence of bismuth-rich regions on the nanoscale, related to remarkably increased carrier concentration and mobility.

The Vinča culture sites of Belovode and Pločnik have been attracting scholarly attention for decades now, due to numerous discoveries indicative of copper mineral and metal use in these settlements, which are confirmed as, currently, the earliest worldwide and very likely developed independently in Eurasia.1 The authors attempt to give an overview of already published data along with new results stemming from the recently completed doctoral research of the primary author.2 All materials related to copper mineral use and pyrometallurgical activities are presented through the concept of metallurgical chaîne opératoire, following the established sequence of operations,3 which is adjusted for this specific case study and divided into three categories: copper mineral processing, (s)melting debris, and the making and working of finished metal objects. The qualitative overview of available data is therefore focused mainly around the material side of the studied samples and provides an insight into the technological choices for making copper mineral ornaments and copper metal artefacts in the sites of Belovode and Pločnik. Accordingly, it provides a model for the understanding of similar material assemblages that occur in other Vinča culture sites, or beyond. [Projekat Ministarstva nauke Republike Srbije, br.177012: Society, spiritual and material culture and communications in the prehistory and early history of the Balkans]

Mit der in Deutschland geplanten Verpflichtung zur Phosphorrückgewinnung im Rahmen der Abwasserbehandlung erlangt das Thema Phosphor-Recycling für Kommunen und Industrie zunehmend Relevanz. Bedingt durch ihre große Oberfläche und Oberflächenladung besitzen Calciumsilicathydrate (CSH) ein bedeutendes Potenzial als Reaktionsmaterial. CSH-Phasen werden aus Quarz, Kalk und Wasser unter erhöhten Druck- und Temperaturbedingungen hergestellt. Dieser Beitrag widmet sich der CSH-Synthese im Hinblick auf eine Optimierung der Phosphor-Rückgewinnung unter Verwendung leicht verfügbarer und günstiger Rohstoffe.

We combine aluminum back surface field (Al-BSF) solar cell precursors with an additional rear side infrared active floating emitter in a tandem cell configuration. This emitter is implemented area selectively by fs-laser hyperdoping in a sulfurous atmosphere. Its design as a floating emitter conceals losses induced by the laser process as long as n-doping occurs. All processes are adapted and supplemented by just a single new process step.

The cycling of mercury between ocean and atmosphere is an important part of the global Hg cycle. Here we study the regional contribution of the air-sea exchange in the North- and Baltic Sea region. We use a newly developed coupled regional chemistry transport modeling (CTM) system to determine the flux between atmosphere and ocean based on the meteorological model COSMO-CLM, the ocean-ecosystem model ECOSMO, the atmospheric CTM CMAQ and a newly developed module for mercury partitioning and speciation in the ocean (MECOSMO). The model was evaluated using atmospheric observations of gaseous elemental mercury (GEM), surface concentrations of dissolved gaseous mercury (DGM), and air-sea flux (ASF) calculations based on observations made on seven cruises in the western and central Baltic Sea and three cruises in the North Sea performed between 1991 and 2006. It was shown that the model is in good agreement with observations: DGM (Normalized Mean Bias NMB=-0.27 N=413), ASF (NMB=-0.32, N=413), GEM (NMB=0.07, N=2359). Generally, the model was able to reproduce the seasonal DGM cycle with the best agreement during winter and autumn (NMBWinter=-0.26, NMBSpring=-0.41, NMBSummer=-0.29, NMBAutumn=-0.03). The modelled mercury evasion from the Baltic Sea ranged from 3400 to 4000 kg/a for the simulation period 1994–2007 which is on the lower end of previous estimates. Modelled atmospheric deposition, river inflow and air-sea exchange lead to an annual net Hg accumulation in the Baltic Sea of 500 to 1000 kg/a. For the North Sea the model calculates an annual mercury flux into the atmosphere between 5700 and 6000 kg/a. The mercury flux from the ocean influenced coastal atmospheric mercury concentrations. Running CMAQ coupled with the ocean model lead to better agreement with GEM observations. Directly at the coast GEM concentrations could be increased by up to 10% on annual average and observed peaks could be reproduced much better. At stations 100km downwind the impact was still observable but reduced to 1–3%.

Deprotonative metalation has been largely used to functionalize aromatic compounds. The efficiency of such reactions, as well as their regioselectivity, depends on the substituents connected to the rings. In contrast with other groups such as fluorine and methoxy, bromine exhibits a long-range acidifying effect. Here we try to depict this particular effect of bromine through different examples in which deprotometalation takes place at a remote position.

This paper presents the results and the limits of 1-D analytical modeling of electrostatic potential in the low-doped p type silicon body of the asymmetric n-channel DG SOI MOSFET, where the contribution to the asymmetry comes only from p- and n-type doping of polysilicon used as the gate electrodes. Solving Poisson's equation with boundary conditions based on the continuity of normal electrical displacement at interfaces and the presence of a minimum electrostatic potential by using the Matlab code we have obtained a minimum potential with a slow variation in the central zone of silicon with the value pinned around 0.46 V, where the applied VGS voltage varies from 0.45 V to 0.95 V. The paper states clearly the validity domain of the analytical solution and the important effect of the localization of the minimum electrostatic potential value on the potential variation at interfaces as a function of the applied VGS voltage.

Die elektrochemische Stabilitat von verschiedenen Elektrodenmaterialien, die zur Entfernung von Eisen aus Kalk-Natron-Glasschmelzen verwendet werden sollen, wurde untersucht. Als Elektrodenmaterialien wurden Kohlenstoff, Molybdan, Platin und Zinnoxid eingesetzt. Die Untersuchungen wurden bei einer Temperatur von 1400 °C unter realitatsnahen Bedingungen, d.h. bei Atmosphare mit einem Sauerstoffpartialdruck, ahnlich wie in einer Glaswanne, durchgefuhrt. Nach verschiedenen Reaktionsdauern wurden die Elektroden sowie die Grenzflache zum Glas mittels visueller Inspektion sowie REM/EDX charakterisiert. Investigations on the electrochemical stability of several materials, which are used as electrodes for the removal from iron in soda lime glass melts, are presented. Carbon, molybdenum, platinum, and tin oxide were studied as electrode materials. The experiments were carried out at a temperature of 1400 °C with oxygen partial pressures typical for glass melting tanks. After different reaction times both the electrode surfaces as well the interface region of the glass close to the interface was characterized visually as well as with SEM/EDX.

A method for the decontamination of water, with concomitant hydrogen formation, is herein described. Formaldehyde is an impurity that is often present in industrial wastewater in significant quantities. The formaldehyde decomposition is possible with a series of ruthenium catalysts which are accessible within minutes via microwave-assisted synthesis.