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Insects in grain can cause serious problems, not only because they feed on the grains. Mass reproduction also causes additional moisture and heat due to the insects' metabolism. This leads to favourable conditions for moulds, which can cause major losses and the formation of mycotoxins. It is therefore important to detect and treat an infestation at an early stage. The "Beetle Sound Tube" system was developed as an acoustic early detection system for insects in grain, which makes it possible to detect even very low levels of infestation and inform the storekeeper by e-mail. The acoustic system remains in the grain during the storage period, and permanently records insect sounds. Challenges were encountered in the development of this acoustic monitoring system, such as analysing very quiet insect sounds in a noisy agricultural environment. In addition, the amount of data collected and the speed of analysis had to be optimised to achieve justin- time detection of insects. The acoustic tube system was developed for silos, flat stores and big bags and is therefore widely applicable. [ABSTRACT FROM AUTHOR]

Kammern-Grubgraben is among the few stratified Upper Palaeolithic sites in Central Europe dating to the Last Glacial Maximum which provided not only substantial amounts of archaeological materials but also extensive preserved occupational structures. Although the site has been known since the last quarter of the 19th century, systematic excavations didn't start until the 1980's. These were carried out subsequently by two different teams providing partly incongruent observations and interpretations. Renewed field investigations commenced in 2015 and aim at reassessing stratigraphy and chronology, settlement structures and occupational sequence, as well as mobility and economy. First results provide a robust multi-method chrono-stratigraphic bracket for occupation between Greenland Stadials GS-3 and GS-2.1. Artefact technology and typology point at supra-regional contacts to both the west and east on a more general scale while a high degree of mobility is specifically demonstrated for the hunter-gatherer groups occupying the site by displaying procurement patterns for various raw materials targeting not only local, but also regional and far-distance sources. Furthermore, the new investigations have been able to almost double the previously established site extent, and targeted excavations show that the diversity and complexity of stone constructions considerably exceeds what has previously been observed. [ABSTRACT FROM AUTHOR]

Proton transport is an elementary process in the selective catalytic reduction of nitrogen oxides by ammonia (DeNOx by NH3-SCR) using metal-exchanged zeolites as catalysts. This review summarizes recent advancements in the study of proton transport in zeolite catalysts using in situ electrical impedance spectroscopy (IS) under NH3-SCR reaction conditions. Different factors, such as the metal cation type, metal exchange level, zeolite framework type, or formation of intermediates, were found to influence the proton transport properties of zeolite NH3-SCR catalysts. A combination of IS with diffuse reflection infrared Fourier transformation spectroscopy in situ (in situ IS-DRIFTS) allowed to achieve a molecular understanding of the proton transport processes. Several mechanistic aspects, such as the NH3-zeolite interaction, NO-zeolite interaction in the presence of adsorbed NH3, or formation of NH4+ intermediates, have been revealed. These achievements indicate that IS-based in situ methods as complementary tools for conventional techniques (e.g., in situ X-ray absorption spectroscopy) are able to provide new perspectives for the understanding of NH3-SCR on zeolite catalysts. [ABSTRACT FROM AUTHOR]

Since 2005, annual excavation campaigns have been conducted at the open air site of Krems-Wachtberg in eastern Austria. This paper provides an overview of the preliminary archaeological results, including a presentation of the site's Upper Palaeolithic features and find inventories, as well as a discussion of its position within the Gravettian of the Middle Danube region. The site is characterized by a well-developed occupation layer with associated features like hearths and burials. From a local perspective, the station is part of an extensive Gravettian settlement cluster on the Wachtberg promontory. Beyond that, more far-ranging connections can be established to sites of the older Gravettian forming the regional group of the Pavlovian. These analogies apply to topographic position and economic factors, as well as to technological and typological criteria of the lithic inventories. Furthermore, parallels in burial rituals and art are evident. [ABSTRACT FROM AUTHOR]

While the influence of various fabrication parameters during deposition on the ferroelectricity of hafnium oxide has been extensively studied, the effect of different atmospheres on the actual switching process has not yet been investigated. In this work, we characterized the ferroelectric properties of undoped hafnium oxide prepared by reactive sputtering under three different atmospheres: dry oxygen/nitrogen, wet nitrogen, and vacuum conditions. We found a significant correlation between dry and wet atmospheres and resulting polarization. Specifically, we observed a direct effect on ferroelectric switching when the film was exposed to dry atmospheres and vacuum, resulting in a higher electric field necessary to initialize the wake-up effect due to an initial imprint effect. Increasing the amount of wet nitrogen during switching decreased the imprint and lowered the necessary voltage required for the wake up. We present a simple model that explains and discusses the incorporation of moisture and its resulting consequences on the ferroelectric properties of hafnium oxide. Additionally, kinetic Monte Carlo simulations showed that the addition of protons to the oxide thin film leads to a lowering of the potential and to a redistribution of protons and oxygen vacancies, which reduces the initial imprint. [ABSTRACT FROM AUTHOR]

Abstract: Recent archaeological excavations at the Upper Palaeolithic open-air site of Krems-Wachtberg in eastern Austria exposed a late Pleistocene loess sequence. An interdisciplinary sampling strategy was applied to the 8-m high North profile. The extraordinary conservation of a Gravettian living floor with several complex features is discussed in this paper. [Copyright &y& Elsevier]

Abstract: Volume-doped CoTiO3 was synthesized via the polyol method. As volume dopants Gd, Ho, K, La, Li, Na, Pb, Sb, and Sm with a concentration of 2at.% were applied. By X-ray diffraction (XRD) materials structure was confirmed, while the materials morphology was imaged using scanning electron microscopy (SEM). Thick films of the nanocrystalline material were applied with a laboratory robotic system to a 8×8 multielectrode substrate. We show that the p-type semiconducting material doped with various metals is applicable for the fast detection of ethanol and propylene. The volume dopants affect the sensing and response behavior of the base material. [Copyright &y& Elsevier]

Abstract: Perovskite-type LnMO3 (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M=Cr, Fe) oxides were prepared by the polyol mediated synthesis. Thick films of the prepared materials were electrically characterised using high throughput impedance spectroscopy (HT-IS). All samples showed p-type semiconductivity. Ethanol and propylene were used to test the gas sensing behaviour in a temperature range from 200 to 500°C. A correlation between the (Ln–O) binding energy and the sensing properties is observed. [Copyright &y& Elsevier]

Abstract: p-Type semiconducting nanocrystalline CoTiO3:La (2at.%) was synthesized via polyol method. X-ray diffraction (XRD) was used to confirm the materials structure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to image the materials morphology. Thick films of the nanocrystalline material were applied with a laboratory roboting system to an 8×8 multielectrode substrate, developed for high-throughput impedance spectroscopy (HTIS). With this method it was shown that the base material doped with various metals (Au, Ce, Ir, Pd, Pt, Rh, Ru) in different concentrations (0.2–0.6at.%) is applicable for the fast detection of ethanol, propylene and NO2, depending on the surface doping and the operation temperature. [Copyright &y& Elsevier]

Fracture repair, which aims at regaining the functional competence of a bone, is a complex and multifactorial process. For the success of fracture repair biology and mechanics are of immense importance. The biological and mechanical environments must be compatible with the processes of cell and tissue proliferation and differentiation. The biological environment is characterized by the vascular supply and by many biochemical components, the biochemical milieu. A good vascular supply is a prerequisite for the initiation of the fracture repair process. The biochemical milieu involves complex interactions among local and systemic regulatory factors such as growth factors or cytokines. The mechanical environment is determined by the local stress and strain within the fracture. However, the local stress and strain is not accessible, and the mechanical environment, therefore, is described by global mechanical factors, e.g., gap size or interfragmentary movement. The relationship between local stress and strain and the global mechanical factors can be obtained by numerical models (Finite Element Model). Moreover, there is considerable interaction between biological factors and mechanical factors, creating a biomechanical environment for the fracture healing process. The biomechanical environment is characterized by osteoblasts and osteocytes that sense the mechanical signal and express biological markers, which effect the repair process. This review will focus on the effects of biomechanical factors on fracture repair as well as the effects of age and osteoporosis. [ABSTRACT FROM AUTHOR]

Abstract: Assessment of fracture healing is a common problem in orthopaedic practice and research. To determine the effectiveness of certain treatments, drugs, mechanical loads, or rehabilitation regimes, the strength of the fracture callus must be determined. Both clinically and experimentally, there is a need to noninvasively and quantitatively evaluate fracture callus quality during healing. The objective of this study was to develop a method to assess fracture stiffness using micro-computed tomography (micro-CT) and finite element analysis. The method was developed and validated with plastic phantoms of various cross sections and known material properties, tested experimentally in four-point bending and torsion. The method was then applied to fractured rat femurs after 3 and 4 weeks of healing tested experimentally in torsion (50 femurs total). Micro-CT scans were made of the fracture calluses to determine three-dimensional geometry and material properties for the finite element models. Experimentally measured torsional rigidities were compared to finite element solutions. Finite element model predictions of callus rigidity correlated significantly better with experimental torsional rigidity than other common measures of healing progress such as callus area, bone mineral density, or area moment of inertia. Using FEA to predict mechanical properties of the callus could prove to be a useful tool in fracture-healing studies. [Copyright &y& Elsevier]

Over the past 20 years, 68Ga-labelled radiopharmaceuticals have become an important part in clinical routine. However, the worldwide supply with 68Ge/68Ga generators is limited as well as the number of patient doses per batch of 68Ga radiopharmaceutical. In the recent years, a new technique appeared, making use of the ease of aqueous labelling via chelators as with 68Ga but using 18F instead. This technique takes advantage of the strong coordinative bond between aluminium and fluoride, realized in the aqueous cation [Al18F]2+. Most applications to date make use of one-pot syntheses with free Al(III) ions in the system. In contrast, we investigated the labelling approach split into two steps: generating the Al-bearing precursor in pure form and using this Al compound as a precursor in the labelling step with aqueous [18F]fluoride. Hence, no free Al3+ ions are present in the labelling step. We investigated the impact of parameters: temperature, pH, addition of organic solvent, and reaction time using the model chelator NH2-MPAA-NODA. With optimized parameters we could stably achieve a 80% radiochemical yield exerting a 30-min reaction time at 100 °C. This technique has the potential to become an important approach in radiopharmaceutical syntheses. [ABSTRACT FROM AUTHOR]

A prospective observational study comparing mechanical power density (MP normalized to dynamic compliance) with traditional spontaneous breathing indexes (e.g., predicted body weight normalized tidal volume [VT/PBW], rapid shallow breathing index [RSBI], or the integrative weaning index [IWI]) for predicting prolonged weaning failure in 140 tracheotomized patients. We assessed the diagnostic accuracy of these indexes at the start and end of the weaning procedure using ROC curve analysis, expressed as the area under the receiver operating characteristic curve (AUROC). Weaning failure occurred in 41 out of 140 patients (29%), demonstrating significantly higher MP density (6156 cmH2O2/min [4402–7910] vs. 3004 cmH2O2/min [2153–3917], P < 0.01), lower spontaneous VT/PBW (5.8 mL*kg−1 [4.8–6.8] vs. 6.6 mL*kg−1 [5.7–7.9], P < 0.01) higher RSBI (68 min−1*L−1 [44–91] vs. 55 min−1*L−1 [41–76], P < 0.01) and lower IWI (41 L2/cmH2O*%*min*10−3 [25–72] vs. 71 L2/cmH2O*%*min*10-3 [50–106], P < 0.01) and at the end of weaning. MP density was more accurate at predicting weaning failures (AUROC 0.91 [95%CI 0.84–0.95]) than VT/PBW (0.67 [0.58–0.74]), RSBI (0.62 [0.53–0.70]), or IWI (0.73 [0.65–0.80]), and may help clinicians in identifying patients at high risk for long-term ventilator dependency. [ABSTRACT FROM AUTHOR]

The article discusses the diverse fabrication method used to decorate nanostructures which are composed of semiconducting, organic, and metallic materials. It states that the nanostructures are utilized as building blocks for complex structures' self-assembly. It mentions that the decoration of the materials based from nanoparticles control its spacing and the balance of the assemblies. Moreover, designing nanostructures can be achieved through DNA linkers which have oglionucleotide strands.

Advancing the synthesis of HfO2 nanocrystals, a refined anhydrous protocol that enables kinetic trapping of the metastable tetragonal phase and modulates twinning defects in anisotropically grown monoclinic nanoprisms is presented. This evolved sol–gel approach examines the role of the capping agent tri‐n‐octylphosphine oxide (TOPO) and introduces a novel heating strategy with sequential growth stages. Replacement of TOPO with triphenylphosphine oxide (TPPO) leads to the formation of prismatic hafnia nanocrystals exhibiting pristine {011}‐facets of the monoclinic phase. Furthermore, a hot‐injection inspired heating approach yields sub‐4 nm isotropic HfO2 nanocrystals in the tetragonal phase, bypassing the need for aliovalent cation species. In contrast, a heat‐up approach culminates in the generation of well‐characterized HfO2 nanorods. With sophisticated transmission electron microscopy analysis and the Wulff construction method, insights into the structural nucleation of nanoparticle growth are provided. This synthesis offers exceptional control and facilitates the formation of self‐assemblies akin to liquid crystals, opening the door for new applications with nanocolloidal HfO2. [ABSTRACT FROM AUTHOR]

Chemically synthesized gold nanoparticles (AuNPs) have attracted much interest for application in various technologically relevant fields including nanoelectronics. In this particular research area, the most promising approach to take full advantage of the tunability in size, shape, and ligand composition of nanoparticles is the integration of a well‐defined number of AuNPs into a nanoscale device. This short review highlights recent progress in the introduction of AuNP into nanoelectronic circuitry by means of selected examples, that demonstrate a "proof‐of‐concept". Synthetic concepts to obtain isotropic and Janus‐like particles as well as lithographic techniques that allow for the fabrication of nanoelectrode structures, which enable the electrical addressing of individual nanoparticles, are presented. A particular focus of this work is the question of how distinct molecular properties can be addressed in a technologically applicable device geometry by controlling the molecular functionalities in the proximity of semiconductor technology. [ABSTRACT FROM AUTHOR]

Resistive switching (RS) for nonvolatile data storage is a highly relevant field of research. Up to now, RS devices are fabricated via semiconductor processing technologies. This poses the question of whether integration of chemically tailored nanoparticles, either consisting of valence change or phase change materials, can be integrated in nanoelectrode configurations in order to explore their functionality for RS applications. This review discusses the RS properties of such nanoparticles by means of selected examples of both nanoparticle assemblies as well as on the individual particle level. Although this field of research is rather unexplored, it becomes evident that chemically tailored nanoparticles bear great potential for RS applications. [ABSTRACT FROM AUTHOR]

As a novel strategy to overcome some of the therapeutic disadvantages of 6-thioguanine (TG) and 6-mercaptopurine (MP), we propose the inclusion of these drugs in βcyclodextrin (βCD) to form the complexes βCD-TG and βCD-MP, followed by subsequent interaction with gold nanoparticles (AuNPs), generating the ternary systems: βCD-TG-AuNPs and βCD-MP-AuNPs. This modification increased their solubility and improved their stability, betting by a site-specific transport due to their nanometric dimensions, among other advantages. The formation of the complexes was confirmed using powder X-ray diffraction, thermogravimetric analysis and one and two-dimensional NMR. A theoretical study using DFT and molecular modelling was conducted to obtain the more stable tautomeric species of TG and MP in solution and confirm the proposed inclusion geometries. The deposition of AuNPs onto βCD-TG and βCD-MP via sputtering was confirmed by UV–vis spectroscopy. Subsequently, the ternary systems were characterized by TEM, FE-SEM and EDX to directly observe the deposited AuNPs and evaluate their sizes, size dispersion, and composition. Finally, the in vitro permeability of the ternary systems was studied using parallel artificial membrane permeability assay (PAMPA). [ABSTRACT FROM AUTHOR]

Surface acoustic wave (SAW) devices are well known for mass-sensitive sensor applications. In biosensing applications, chemical and biochemically evoked binding processes on surfaces are detected in liquid environments using delay line or resonator sensor configurations, preferably in combination with the appropriate microfluidic devices. All configurations share the common feature of analyzing the transmission characteristic of the propagating SAW. In this paper, a novel SAW-based impedance sensor type is introduced which uses only one interdigital transducer (IDT), simultaneously as the SAW generator and the sensor element. Here, the input port reflection coefficient S11 is measured at the IDT instead of the commonly used S21 transmission forward gain parameter. Thus, a sharp and distinct peak of the S11 spectrum is obtained, enabling a comfortable direct readout of the sensor signal. Proof of the concept was gained by analyzing the specific binding of the 4-mercaptophenylacetic acid gold nanoparticles (MPA-AuNP) directly to the IDT surface. The corresponding binding kinetic of the MPA-AuNP on the functionalized gold surface has been analyzed and a sensitivity of 7.4 mW nM-1 has been determined. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) have been extensively explored in biomedical applications, for example as drug carriers, contrast agents, or therapeutics. However, AuNP can exhibit cytotoxic profile, when the size is below 2 nm (ultrasmall AuNP; usAuNP) and when the stabilizing ligands allow for access to the gold surface either for the direct interaction with biomolecules or for catalytic activity of the unshielded gold surface. Furthermore, usAuNP exhibits significantly different biodistribution and enhanced circulation times compared to larger AuNP. This review gives an overview about the synthesis and the physico-chemical properties of usAuNP and, thereby, focusses on 1.4 nm sized AuNP, which are derived from the compound Au(PPh)Cl and which are the most intensively studied usAuNP in the field. This part is followed by a summary of the toxic properties of usAuNP, which include in vitro cytotoxicity tests on different cell lines, electrophysiological tests following FDA guidelines as well as studies on antibacterial effects. Finally, the biodistribution and pharmacokinetics of ultrasmall AuNP are discussed and compared to the properties of more biocompatible, larger AuNP. [ABSTRACT FROM AUTHOR]

Future vehicle powertrain systems with internal combustion engines must achieve higher efficiencies and further reduced pollutant emissions. This will require the application of new advanced technologies. Against this background, this paper presents a holistic approach to reduce temporally the wall heat losses, and hydrocarbon and carbon monoxide emissions with thermal coatings on the combustion chamber walls. For this purpose, an yttria-stabilized zirconia (YSZ) coating is applied and evaluated by different methods. The thin layer in combination with the low thermal effusivity of the material allows the wall temperature to follow the gas temperature and perform a so-called thermal swing. The interaction between an uncoated and a YSZ-coated wall with the flame front as well as partially burned gas was investigated. First, in terms of the coating's potential to reduce the flame quenching distance using an optical method in a constant volume combustion chamber. Second, regarding its influence on the near-wall gas composition, which was analyzed with in-situ diffuse reflectance infrared Fourier transform spectroscopy measurements and a fast gas sampling technique on a single-cylinder engine. From this, it could be derived that the quenching distance can be reduced by 10% at ambient conditions and by 5% at an elevated temperature of 200 °C by using the coating. These findings also support the results that have been obtained by the near-wall gas composition measurements, where a reduced total hydrocarbon emission was found with the applied coating. [ABSTRACT FROM AUTHOR]

Melphalan (Mel) is an antineoplastic widely used in cancer and other diseases. Its low solubility, rapid hydrolysis, and non-specificity limit its therapeutic performance. To overcome these disadvantages, Mel was included in β-cyclodextrin (βCD), which is a macromolecule that increases its aqueous solubility and stability, among other properties. Additionally, the βCD–Mel complex has been used as a substrate to deposit silver nanoparticles (AgNPs) through magnetron sputtering, forming the βCD–Mel–AgNPs crystalline system. Different techniques showed that the complex (stoichiometric ratio 1:1) has a loading capacity of 27%, an association constant of 625 M−1, and a degree of solubilization of 0.034. Added to this, Mel is partially included, exposing the NH2 and COOH groups that stabilize AgNPs in the solid state, with an average size of 15 ± 3 nm. Its dissolution results in a colloidal solution of AgNPs covered by multiple layers of the βCD–Mel complex, with a hydrodynamic diameter of 116 nm, a PDI of 0.4, and a surface charge of 19 mV. The in vitro permeability assays show that the effective permeability of Mel increased using βCD and AgNPs. This novel nanosystem based on βCD and AgNPs is a promising candidate as a Mel nanocarrier for cancer therapy. [ABSTRACT FROM AUTHOR]

Dacarbazine (DB) is an antineoplastic drug extensively used in cancer therapy. However, present limitations on its performance are related to its low solubility, instability, and non-specificity. To overcome these drawbacks, DB was included in β-cyclodextrin (βCD), which increased its aqueous solubility and stability. This new βCD@DB complex has been associated with plasmonic gold nanoparticles (AuNPs), and polyethylene glycol (PEG) has been added in the process to increase the colloidal stability and biocompatibility. Different techniques revealed that DB allows for a dynamic inclusion into βCD, with an association constant of 80 M−1 and a degree of solubilization of 0.023, where βCD showed a loading capacity of 16%. The partial exposure of the NH2 group in the included DB allows its interaction with AuNPs, with a loading efficiency of 99%. The PEG-AuNPs-βCD@DB nanosystem exhibits an optical plasmonic absorption at 525 nm, a surface charge of −29 mV, and an average size of 12 nm. Finally, laser irradiation assays showed that DB can be released from this platform in a controlled manner over time, reaching a concentration of 56 μg/mL (43% of the initially loaded amount), which, added to the previous data, validates its potential for drug delivery applications. Therefore, the novel nanosystem based on βCD, AuNPs, and PEG is a promising candidate as a new nanocarrier for DB. [ABSTRACT FROM AUTHOR]

In the course of extensive excavations at the Upper Palaeolithic open-air site of Krems-Wachtberg, a large assemblage as well as extraordinarily well preserved archaeological features have been recovered since 2005. After the completion of the field work, a preliminary overview of the lithic industry can be provided. Artefact-morphological studies allow for the dating of the main cultural layer to the older Gravettian, with specific typological elements indicating an attribution to the Pavlovian stage. Detailed raw material analyses applying stereo-microscopic investigation for all lithic artefacts and geochemical analysis for selected raw material groups revealed a predominantly local raw material economy. Accordingly, the lithic chaîne opératoire is present at the site for most of the identified raw materials. Spatial analyses of selected raw material units in combination with initial refitting-results reflect site formation processes but also indicate specific activity areas within the cultural layer. [ABSTRACT FROM AUTHOR]

The efficiency and robustness of selective catalytic reduction (SCR) by NH3 catalysts for exhaust gas purification, especially of heavy-duty diesel engines, will continue to play a major role, despite the increasing electrification of powertrains. With that in mind, the effect of the synthesis scale on commercially available Cu-exchanged chabazite catalysts for SCR was investigated through physicochemical characterizations and catalytic tests. During hydrothermal aging, both industrial and lab-scale prepared catalysts underwent structural dealumination of the zeolite framework and redistribution of the Al sites. Although both catalysts demonstrated similar NO conversion activity under SCR conditions, the lab-scale catalyst showed higher selectivity and lower activity in NH3 oxidation. Variations in N2O formation and NH3 oxidation rate were found to correlate with the formation of different copper species, and the compositions become less controllable in industrial-scale process. This case study focused on routes of ion exchange, and the results provide new insights into catalytic performance of the industrially-produced zeolites. [ABSTRACT FROM AUTHOR]

We introduce a microwave (MW)-assisted heterogeneous catalytical setup, which we carefully examined for its thermal and performance characteristics. Although MW-assisted heterogeneous catalysis has been widely explored in the past, there is still need for attention towards the specific experimental details, which may complicate the interpretation of results and comparability in general. In this study we discuss technical and material related factors influencing the obtained data from MW-assisted heterogeneous catalysis, specifically in regards to the oxidation of carbon monoxide over a selected perovskite catalyst, which shall serve as a model reaction for exhaust gas aftertreatment. A high degree of comparability between different experiments, both in terms of setup and the catalysts, is necessary to draw conclusions regarding this promising technology. Despite significant interest from both fundamental and applied research, many questions and controversies still remain and are discussed in this study. A series of deciding parameters is presented and the influence on the data is discussed. To control these parameters is both a challenge but also an opportunity to gain advanced insight into MW-assisted catalysis and to develop new materials and processes. The results and discussion are based upon experiments conducted in a monomode MW-assisted catalysis system employing powdered solid-state perovskite oxides in a fixed bed reactor. The discussion covers critical aspects concerning the determination of the actual catalyst temperature, the homogeneity of the thermal distribution, time, and local temperature relaxation (i.e., thermal runaway effects and hotspot formation), particle size effects, gas flow considerations, and system design. [ABSTRACT FROM AUTHOR]

Within the Research Cluster of Excellence "The Fuel Science Center" at RWTH Aachen University, the production and application of new fuels from bio-based carbon feedstocks and CO2 with hydrogen from renewable electricity generation is being investigated. In this study, the storage and oxidation of ethanol, 1-butanol, 2-butanone, cyclopentanone, and cyclopentane as well as two blends thereof on a series production Pt–Pd/Al2O3 oxidation catalyst were investigated. Hydrocarbon (HC) storage and temperature-programmed surface reaction (TPSR) experiments were carried out to analyze their adsorption and desorption behavior. In addition, the individual HCs and both blends were investigated using Diffuse Reflectance Infrared Fourier Transform Spectroscopy (TP-DRIFTS). In general, all oxygenated HCs are adsorbed more strongly than cyclopentane due to their higher polarity. Interestingly, it could be observed that the two different blends [blend 1: ethanol (50 mol %), 2-butanone (21 mol %), cyclopentanone (14 mol %) and cyclopentane (15 mol %); blend 2: 1-butanol (45 mol %), ethanol (29 mol %) and cyclopentane (27 mol %)] exhibit a different storage behavior compared to the single hydrocarbons. It was shown that the presence of 1-butanol and cyclopentane in blend 2 strongly inhibits the oxidation of ethanol. As a result, the ethanol light-off temperature was increased by at least 100 K. A difference was also found in the storage behavior of cyclopentane. While no significant storage could be detected in the pure compound experiment, the experiments with both mixtures showed a larger amount stored. The presence of adsorbed species of the hydrocarbons and their corresponding reaction products has been demonstrated and gives an insight into the storage mechanism of blends. [ABSTRACT FROM AUTHOR]

Zeolites are in use as catalyst materials in the selective catalytic reduction of NO x with NH 3 as reducing agent. An initial NH 3 -adsorption on the catalyst is essential for the reaction with NO and NO 2 to occur. Due to the adsorbed NH 3 , the proton conductivity of the zeolite increases markedly. This change of the electrical properties of the catalyst material can be monitored in a contactless way and in operando using a radio frequency-based method to determine the ammonia loading on the catalyst. In this work, the ammonia storage is examined on a copper exchanged Chabazite Cu-SSZ-13, a typical SCR catalyst as it is in use for serial applications, at different temperatures and various feed ratios. [ABSTRACT FROM AUTHOR]

Since 2005, detailed archaeological investigations have been carried out at the Upper Palaeolithic site of Krems-Wachtberg in eastern Austria where a well-preserved Gravettian find layer is embedded in an 8 m high Late Pleistocene loess sequence. The excavations are accompanied by interdisciplinary sampling strategies applied on the main profiles' entire sediment series as well as on selected locations within the archaeological context. The latter include both evident anthropogenic structures, an in situ occupation surface with hearths and burials, and periglacial features that together determine the morphology and explain the formation of the main Gravettian find horizon. [ABSTRACT FROM AUTHOR]

The classic Upper Palaeolithic location of the Wachtberg in Krems (eastern Austria) features a multitude of exposures in a limited area of about 50,000 m 2 . In addition to Gravettian sites which have been investigated in detail in the course of recent years using modern methods, there are the records of old excavations, several documented sections, as well as a considerable number of core samples displaying heterogeneous documentation standards. This paper provides an overview of these different sources of information and aims at synthesizing the data for a comprehensive understanding of the local loess sedimentation and Palaeolithic occupation. [ABSTRACT FROM AUTHOR]

The catalytic combustion of methane has gained much attention as a sustainable technology, due to concerns about the environmental impact of unburnt methane emissions from the natural gas vehicles. Researchers have explored alternatives to precious metal catalysts for methane combustion, with a focus on perovskite oxides known for their excellent activity and sintering-resistance capacity. In this study, LaFeO 3 perovskite material was synthesized and subsequently subjected to a nitric acid etching treatment to modify its surface. It was found that the acid preferentially dissolved La cations from LaFeO 3 surface while the perovskite phase was unchanged, as a consequence, the etched LaFeO 3 shows improvement in methane combustion activity. The best performance was achieved in the sample with one-hour surface etched treatment, which suggests that the appropriate surface reconstruction induced by acid treatment promotes the formation of more active Fe sites on the surface and reduces the energic barriers of methane activation. This work presents a straightforward and effective approach to tailor the exposed surface properties of perovskites, thereby enhancing their activity in hydrocarbon combustion reactions. [Display omitted] • Nitrate acid treatment is performed to selectively etch the as-prepared LaFeO 3 perovskite for the surface modification. • Nitric acid preferentially dissolves La cations from LaFeO 3 surface, thus more Fe-O termination are exposed as active sites. • 1-h treated LaFeO 3 shows an enhanced CH 4 combustion reaction activity, due to the lowest energic barriers of CH 4 activation. • This work presents an effective approach to tailor the exposed surface properties of perovskites. [ABSTRACT FROM AUTHOR]

The phase-pure zeolite Y with a high n (Si)/ n (Al) ratio is obtained with the cyclic polyether 15-Crown-5 as a structure-directing agent. In copper-exchanged for this new zeolite outperformed other Cu-containing zeolite Y counterparts during NH 3 -SCR-DeNO x with more than 80% NO conversion and more than 85% N 2 selectivity in the temperature range of 100 – 500 °C. The presence of Cu+ species located in sodalite cages with elevated redox cyclability guarantees high activity and N 2 selectivity up to 400 °C over CuY-Crown. Above 400 °C, a high activity and N 2 selectivity are related to the accessibility of chemisorbed NH 3 to the gaseous NO during the NH 3 -SCR-DeNO x. [Display omitted] • Zeolite Y with a high n (Si)/ n (Al) ratio is obtained using 15-Crown-5. • CuY-Crown outperformed other CuY counterparts in NH 3 -SCR-DeNO x. • Cu+ species located in sodalite cages guarantee high activity and N 2 selectivity. [ABSTRACT FROM AUTHOR]

An important prerequisite for molecular shuttle-basedfunctionaldevices is the development of adequate linker chemistries to loadand transport versatile cargoes. Copper-free “click chemistry”has not been applied before to covalently load cargo onto molecularshuttles propelled by biological motors such as kinesin. Due to thehigh biocompatibility and bioorthogonality of the strain-promotedazide-alkyne cycloaddition, this approach has pronounced advantagescompared to previous methods. [ABSTRACT FROM AUTHOR]

Abstract: For numerical simulations of biological processes the assignment of reliable material properties is essential. Since literature data show huge variations for each parameter, this study presents a method for determining tissue properties straight from the investigated specimens by combining electronic speckle pattern interferometry (ESPI) with finite element (FE) analysis in a two-step parameter analysis procedure. ESPI displacement data from two mid-sagittal ovine fracture callus slices under 5N compressive load were directly compared to data from FE simulations of the respective experimental setup. In the first step a parameter sensitivity analysis quantified the influence of single tissues on the mechanical behavior of the callus specimens. In the second step, material properties (i.e. Young''s moduli and Poisson''s ratios) for the most dominant material of each callus specimen were determined through a parameter sampling procedure minimizing the mean local deviations between the simulated (FE) and measured (ESPI) equivalent element strains. The resulting material properties showed reasonable ranges downsizing the variability of previous published values, especially for Young''s modulus which was 1881MPa for woven bone and 16MPa for cartilage in average. In conclusion, a numerical method was developed to determine material properties straight from independent fracture callus specimens based on experimentally derived local mechanical conditions. [Copyright &y& Elsevier]

Abstract: Spinel iron oxide nanoparticles of sizes from 12 to 60nm have been prepared via a hydrothermal synthesis. Thick films of the Fe3−x O4 nanoparticles deposited on interdigital electrodes were applied as resistive gas sensors. The electrical and gas sensing properties were characterized by impedance spectroscopy using multielectrode substrates. The reducing analytes CH4, NO, H2 and NH3 in N2 as a reference were applied in order to investigate the sensor response, the selectivity and the recovery behavior at temperature between 50°C and 300°C. The materials exhibit good sensor responses towards NH3 with low cross sensitivities towards H2 and NO at 250°C. A linearly increasing sensor response towards NH3 and H2 with decreasing particle size was found. [Copyright &y& Elsevier]

Abstract: Osteoporosis is a widely spread disease with severe consequences for patients and high costs for health care systems. The disease is characterised by a loss of bone mass which induces a loss of mechanical performance and structural integrity. It was found that transverse trabeculae are thinned and perforated while vertical trabeculae stay intact. For understanding these phenomena and the mechanisms leading to fractures of trabecular bone due to osteoporosis, numerous researchers employ micro-finite element models. To avoid disadvantages in setting up classical finite element models, composite finite elements (CFE) can be used. The aim of the study is to test the potential of CFE. For that, a parameter study on numerical lattice samples with statistically simulated, simplified osteoporosis is performed. These samples are subjected to compression and shear loading. Results show that the biggest drop of compressive stiffness is reached for transverse isotropic structures losing of the trabeculae (minus 89.8% stiffness). The biggest drop in shear stiffness is found for an isotropic structure also losing 32% of the trabeculae (minus 67.3% stiffness). The study indicates that losing trabeculae leads to a worse drop of macroscopic stiffness than thinning of trabeculae. The results further demonstrate the advantages of CFEs for simulating micro-structured samples. [Copyright &y& Elsevier]

Abstract: Background: Internal loads in long bones are of special interest, for testing and optimization of current implant designs for fracture treatment. Inverse dynamic musculoskeletal models were successfully used to determine the muscle forces in the lower extremities, however the internal loads expressed as forces and moments along the human tibia during gait have not been reported. Methods: A musculoskeletal model of the lower extremities, developed and provided under public domain from the AnyBody research group (www.anybody.aau.dk), was modified to determine the three-dimensional internal loads along the tibial axis during gait. To corroborate this numerical model, the calculated resultant hip contact force as well as the axial force on the tibial plateau were compared to in vivo data from the literature. Findings: The highest internal loads were the axial force with up to 4.7 bodyweight and the bending moment in the sagittal plane with up to 71.6 bodyweight times millimetre in the late stance phase. The extreme values of the internal loads along the tibial axis varied up to 1.5 bodyweight and 85.7 bodyweight times millimetre. In the distal part of the tibia, the axial force dominated the three-dimensional internal load case, whereas the internal moments became more significant with increasing distance from the ankle joint. Interpretation: This study provides for the first time the three-dimensional internal loads, expressed as forces and moments along the human tibia during normal gait. The results of this study could be used to improve the mechanical behaviour of current implant designs for the treatment of tibial fractures to avoid implant failures under in vivo loading conditions. [Copyright &y& Elsevier]

Abstract: This study evaluated the feasibility of assessing continuous strain distributions on fracture callus cross-sections with an electronic speckle pattern interferometry (ESPI) system. Mid-sagittal callus cross-sections were harvested from ovine tibiae. One low stiffness (LS) specimen and one high stiffness (HS) specimen were selected to evaluate the feasibility for strain acquisition over a range of callus properties. The HS specimen was 147 times stiffer in compression than the LS specimen. ESPI captured continuous strain distributions on both specimens. Peak strain was located adjacent to cortical boundaries in the osteotomy gap. In response to 5N compression, peak compressive strain of 5.8% in the LS specimen was over two orders of magnitude higher than peak compressive strain of 0.013% in the HS specimen. In conclusion, ESPI-based strain acquisition enables reproducible quantification of strain distributions on callus cross-sections. Such measurements may support validation of computational models and evaluation of experimental results in fracture healing research. [Copyright &y& Elsevier]

Abstract: The workflow of a high throughput screening setup for the rapid identification of new and improved gas sensor materials is presented. The polyol method was applied to prepare nanoparticulate metal oxides as base materials. These materials have been modified by surface and volume doping. Using multielectrode substrates and high throughput impedance spectroscopy (HT-IS) a wide range of materials could be screened on a short time scale. Selected examples reflect the state of the art for applying HT-IS in search of new selective gas sensing materials. [Copyright &y& Elsevier]

Abstract: Background: A number of clinically used total hip femoral implants are claiming a more or less physiologic load transfer, mostly without providing experimental data. To compare three clinically cementless total hip stems of fundamentally different design, the strain distribution before and after insertion in human cadaver femora was measured in vitro. Methods: A conventional straight stem based on a distal anchorage concept, a so-called “anatomic” stem designed to have a proximal force transmission and a “stemless” femoral neck prosthesis were evaluated under similar loading conditions. Strain distribution was measured with tri-axial strain-gauge rosettes before and after implantation of the stems. The same bending moment was used in all femora tested to compare magnitude and direction of the resulting strains. Findings: The straight and the “anatomic” stem both led to a decrease of the longitudinal strains in the proximal femur, while the femoral neck implant mainly led to an increase of measured strains on the lateral side of the greater trochanter. The observed medial strains were closer to physiological values in the “stemless” prosthesis than those of the two full-stem prosthesis. Interpretation: The decrease in strains seen in the proximal region of the femora with implanted conventional hip prosthesis corresponds well to the decrease of bone density in this region noted in clinical follow-up studies. The more physiological strain at the inferior base of the neck seen in “stemless implant” may induce a remodelling process that better retains bone stock in that area. However, the increase of strains noted after implantation of this prosthesis require further investigation to assess the risk they may pose to bone failure. [Copyright &y& Elsevier]

Abstract: Background: Major deficits of many finite element models of the lumbar spine are the oversimplification, assumed constellation of the material properties or the insufficiently performed calibration using experimental in vitro data. The aim of this study was, to develop a method for calibrating the two-composite structure of the annulus fibrosus, the ground substance and collagen fibers. Methods: For that purpose, a three-dimensional, non-linear finite element model of a denucleated intervertebral disc with the adjacent vertebral bodies (L4–L5) was created. Previously performed in vitro experiments provided experimental data for the range of motion in each load direction, needed for calibration. A method was developed to determine the individual contribution of the fibers and the ground substance for bending moments with four different magnitudes (2.5, 5.0, 7.5 and 10Nm). For each bending moment, the stiffness of fibers was varied to approximate the Young’s modulus of the ground substance in order to fulfil the required range of motion obtained from in vitro results within an accuracy of 99%. Results: Infinite material parameter combinations of collagen fibers and ground substance led to the same range of motion, which were different for each bending moment. However, there was only one combination, which was valid for all applied bending moments; and in all load direction. Interpretation: This calibration method was performed on range of motion data; however, the procedure could also be applied to other loading scenarios and measurement parameters like disc bulge, translation and intradiscal pressure. [Copyright &y& Elsevier]

Spatially resolved luminescence and Raman spectroscopy investigations are applied to a series of (1122)-GaN samples grown by hydride vapor phase epitaxy (HVPE) grown over an initial layer deposited by metal organic vapor phase epitaxy on patterned sapphire substrates. Whereas these two differently grown GaN layers are crystallographically homogeneous, they differ largely in their doping level due to high unintentional oxygen uptake in the HVPE layer. This high doping shows up in luminescence spectra, which can be explained by a free-electron recombination band for which an analytical model considering the Burstein-Moss shift, conduction band tailing, and the bandgap renormalization is included. Secondary ion mass spectrometry, Raman spectroscopy, and Hall measurements concordantly determine the electron density to be above 1019cm-3. In addition, the strain state is assessed by Raman spectroscopy and compared to a finite element analysis. [ABSTRACT FROM AUTHOR]

Musculoskeletal research questions regarding the prevention or rehabilitation of the hand can be addressed using inverse dynamics simulations when experiments are not possible. To date, no complete human hand model implemented in a holistic human body model has been fully developed. The aim of this work was to develop, implement, and validate a fully detailed hand model using the AnyBody Modelling System (AMS) (AnyBody, Aalborg, Denmark). To achieve this, a consistent multiple cadaver dataset, including all extrinsic and intrinsic muscles, served as a basis. Various obstacle methods were implemented to obtain with the correct alignment of the muscle paths together with the full range of motion of the fingers. These included tori, cylinders, and spherical ellipsoids. The origin points of the lumbrical muscles within the tendon of the flexor digitorum profundus added a unique feature to the model. Furthermore, the possibility of an entire patient-specific scaling based on the hand length and width were implemented in the model. For model validation, experimental datasets from the literature were used, which included the comparison of numerically calculated moment arms of the wrist, thumb, and index finger muscles. In general, the results displayed good comparability of the model and experimental data. However, the extrinsic muscles showed higher accordance than the intrinsic ones. Nevertheless, the results showed, that the proposed developed inverse dynamics hand model offers opportunities in a broad field of applications, where the muscles and joint forces of the forearm play a crucial role. [ABSTRACT FROM AUTHOR]

The washcoat composition and the catalytic properties of two commercially available lean NOx traps (LNTs) were investigated. Both catalysts contained nominally the same NOx storage and catalytic materials but differed strongly in their amount and activity as well as in the composition of their layered washcoat architecture. In lean‐rich cycle experiments under realistic engine‐out gas compositions using a laboratory gas test bench, the LNTs showed comparable NOx storage behavior. At temperatures below 250 °C, the lean phase durations last up to 300 s until 50 % of the NOx storage capacity is reached. The simultaneously calculated NOx storage efficiencies drop rapidly below 35 %, resulting in a high NOx slip. Strong variations were observed in N2O and NH3 selectivity and in CO slip during regeneration of both LNTs caused by the different oxygen storage capacity (OSC), water gas shift (WGS) activity and rhodium distribution in the catalytic layers. Based on the obtained results, proposals were made to optimize the storage and regeneration performance, leading to highly efficient LNT catalysts for coupling with a downstream SCR catalyst. [ABSTRACT FROM AUTHOR]

The AnyBody Modeling System™ (AMS) is a musculoskeletal software simulation solution using inverse dynamics analysis. It enables the determination of muscle and joint forces for a given bodily motion. The recording of the individual movement and the transfer into the AMS is a complex and protracted process. Researches indicated that the contactless, visual Leap Motion Controller (LMC) provides clinically meaningful motion data for hand tracking. Therefore, the aim of this study was to integrate the LMC hand motion data into the AMS in order to improve the process of recording a hand movement. A Python-based interface between the LMC and the AMS, termed ROSE Motion, was developed. This solution records and saves the data of the movement as Biovision Hierarchy (BVH) data and AnyScript vector files that are imported into the AMS simulation. Setting simulation parameters, initiating the calculation automatically, and fetching results is implemented by using the AnyPyTools library from AnyBody. The proposed tool offers a rapid and easy-to-use recording solution for elbow, hand, and finger movements. Features include animation, cutting/editing, exporting the motion, and remote controlling the AMS for the analysis and presentation of musculoskeletal simulation results. Comparing the motion tracking results with previous studies, covering problems when using the LMC limit the correctness of the motion data. However, fast experimental setup and intuitive and rapid motion data editing strengthen the use of marker less systems as the herein presented compared to marker based motion capturing. [ABSTRACT FROM AUTHOR]

Lithium-oxygen (Li-O2) batteries require rational air electrode concepts to achieve high energy densities. We report a simple but effective electrode design based on graphite nanosheets (GNS) as active material to facilitate the discharge reaction. In contrast to other carbon forms we tested, GNS show a distinctive two-step discharge behavior. Fundamental aspects of the battery's discharge profile were examined in different depths of discharge using scanning electron microscopy and electrochemical impedance spectroscopy. We attribute the second stage of discharge to the electrochemically induced expansion of graphite, which allows an increase in the discharge product uptake. Raman spectroscopy and powder X-ray diffraction confirmed the main discharge product to be Li2O2, which was found as particulate coating on GNS at the electrode top, and in damaged areas at the bottom together with Li2CO3 and Li2O. Large discharge capacity comes at a price: the chemical and structural integrity of the cathode suffers from graphite expansion and unwanted byproducts. In addition to the known instability of the electrode–electrolyte interface, new challenges emerge from high depths of discharge. The mechanistic origin of the observed effects, as well as air electrode design strategies to deal with them, are discussed in this study. [ABSTRACT FROM AUTHOR]

Abstract We describe a facile and simple solid-state thermolysis route for the preparation of Co, Ni, and Fe phosphide nanoparticles embedded in amorphous carbon using an organometallic complex. This was achieved by using a suitable organometallic complex in a single step synthetic route without using any solvent or catalyst. The advantage of using such precursor was to offer a source for metal, phosphorus and carbon without using any additional sources. The morphology of products was characterized by transmission electron microscopy, scanning electron microscopy and nature of carbon was analyzed using the Raman microscope and X-ray diffraction. The electrocatalytic oxygen evolution reaction (OER) activity and stability of the metal phosphide nanostructure was evaluated using the rotating disk electrode technique. The CoP, NiP and FeP exhibit the OER overpotential of 370, 380 and 550 mV at 10 mA cm−2, respectively in 0.1 M KOH electrolyte. Among prepared phosphide catalysts, cobalt phosphide shows a lowest Tafel slope indicate favorable kinetics for the OER activity than nickel and iron phosphide catalysts. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Within the Research Cluster of Excellence "Tailor-Made Fuels from Biomass" at RWTH Aachen University, novel fuels from biomass for internal combustion engines are investigated. The new fuels tend to soot less, which allows to increase exhaust gas recirculation for reduction of nitrogen oxides (NOx) emissions. This increases the emissions of unburnt hydrocarbons (HC), while the composition of the HC emissions changes because of the changed fuel composition. The impact of 16 different oxygen-free and oxygenated hydrocarbons (1-octanol, di-n-butyl ether (DNBE), 2-butanone and ethanol as examples for bio-derived fuels; toluene and n-heptane as examples for conventional fuels' components; propane, propene, ethane, ethene, ethyne, methane, n-butane, isobutane, n-pentane and 2-propanol as HC known to be in exhaust gases) on a series production Pt-Pd/Al2O3 oxidation catalyst on a cordierite substrate has been investigated regarding adsorption and temperature programmed oxidation (TPO). In general, due to higher polarity oxygenated HC are stronger adsorbed than oxygen-free ones. For 1-octanol, an extraordinary high adsorption could be observed associated with vigorous exothermal oxidation reaction during TPO. Additionally, the temperature programmed desorption of 1-octanol and ethanol has been investigated by Diffuse Reflectance Infrared Fourier Transform Spectroscopy (TP-DRIFTS). Adsorbed alcohol species as well as oxidized products were demonstrated to be present. [ABSTRACT FROM AUTHOR]