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The cost-efficient production of green hydrogen using renewable energies requires next-generation proton exchange membrane (PEM) electrolysers to be operated at higher current density. Under this new operating condition, the elevated temperature of the ultra-pure water and its supersaturation with oxygen on the anode side have strong effects on the formation and transport of gas bubbles. The resulting gas-liquid two-phase flow through the porous transport layer at the membrane electrode assembly is characterised by up to 50 % gas fraction, which is exceptionally high. Such a foam-like flow within the porous medium is not accessible by optical measurements. Instead, we performed imaging flow measurements by means of time-resolved radiography using polychromatic X-rays as well as thermal neutrons at 100 frames per second imaging frame rate. On a laboratory scale, we aimed to study the bubble transport by mapping the local gas fraction distribution over time. This conference contribution presents two model experiments with open-porous metal and polymer foams, namely made of nickel and polyurethane, showcasing the advantages but also limitations of X-ray and neutron radiography for investigating bubble transport phenomena within such foam structures. In both experiments, foam samples of approximately 70 mm x 70 mm in width and height were sandwiched between the X-ray- or neutron-transparent front and back windows of a vessel filled with deionised water. As neutrons are strongly attenuated in water, the thickness of the water-filled vessel and the foam sample were set to 5 mm along the beam direction in all measurements. Bubbles were generated continuously by injecting compressed air at different but constant volumetric flow rates through a single hollow needle releasing the bubbles directly into the water-soaked foam. Based on calibration radiographs acquired both in the absence and presence of water, quantitative image analysis yielded a pixelwise mapping of the gas fraction at approximately 0.06 mm image pixel size without binning. While X-ray radiography visualised the pulsating transport of bubble plumes through a nickel foam of 1.2 mm pore size, neutron radiography gave insights into the jumping motion of single bubbles through a polyurethane foam of approximately 3 mm pore size. In conclusion, we characterised the gas transport depending on the volumetric gas flow rate, the bubble size in relation to the foam pore size and the wettability of the inner foam surface. Further radiographic studies will consider bubble flows through open-porous materials with different pore geometry or functionalised surface wettability.

Porous materials are frequently used as e.g. electrodes or porous transport layers in various types of electrolyzers. A better understanding of the bubble dynamics on porous electrodes is especially important to optimize new electrolyzer designs like membraneless electrolyzers. The developed 3-electrode cell was optimized with regard to the analysis of the bubble nucleation, growth and detachment on the applied working electrode. Noteworthy in this regard is the 2-dimensional optical measurement system to characterize the bubble dynamics from the side and top. The cell provides a platform to run parametric studies in alkaline electrolytes. The present data set compares three different expanded nickel metals at applied current densities of |j|= 10, 20, 50, 100 or 200 mA/cm² and flow rates of ̇V̇ = 0 or 5 ml/min. As electrolyte 1 M KOH is used. An overview of all performed experiments and the main parameters (current density j and flow rate V̇) is given in the file Overview of all performed experiments.pdf. The data is analyzed as described in the corresponding journal publication Bubble size distribution and electrode coverage at porous nickel electrodes in a novel 3-electrode flow-through cell. For each parameter set 3 data sets are given to ensure statistical confidence. Each data set, stored as .hdf5-file, is structured in groups as follows: Electrochemical Measurement Data Sideview Raw Images Topview Raw Images Results Detected Bubbles Electrode Coverage In the attributes assigned to the groups in the .hdf5-file all relevant metadata is given, including the experimental parameters, used devices and characteristics of the mounted WE. In addition to exemplary data sets for all three electrodes, the CAD files of the experimental setup used and sample videos of the raw images are also provided within this data publication. The remaining data sets of all measurements performed can be made available upon request.

Co encapsulated in N-doped carbon nanotubes (Co-NCNT) catalysts are of high interest as bifunctional electrocatalyst material for both efficient oxygen evolution and reduction (OER/ORR) in applications of rechargeable metal-air batteries. Up to now, the role played by the functional metal species in OER/ORR is still insufficiently understood. The main focus of our research is to shed light on the mechanistic role of the Co species that serve as active sites in the bi-functional Co-NCNT catalysts. It is found that S700 exhibits an outstanding OER/ORR activity. We thus hypothesize that CoII and CoIII clusters predominately function as active sites in the OER and ORR processes, respectively. Furthermore, OER/ORR activity for Co-NCNT catalyst primarily correlates to eg occupation. A near-unity occupancy of the eg orbital of S700 is revealed to be the cause for the maximum intrinsic OER/ORR activity, which provides guidelines for the design of highly active catalysts.

Background: Caregivers play a key role in the success of trauma-focused cognitive behavioural therapy (TF-CBT). Yet, the effect of their alliance on treatment outcomes besides the other parties in treatment has hardly been studied. Objective: This study examined the working alliance (WA) of therapists, patients and caregivers in TF-CBT and its contribution on treatment outcome over time. Methods: N = 76 children and adolescents (mean age = 12.66 years, range 7–17, M/F ratio: .43) participated in the TF-CBT arm of a randomized controlled trial. The WA was assessed with the Working Alliance Inventory Short Version (WAI-S) at two measurement points, while symptom level of posttraumatic stress symptoms (PTSS) was assessed with the Clinician-Administered PTSD Scale for Children and Adolescents (CAPS-CA). Paired sample t-tests, intraclass correlations (ICC), and mixed-effects regression models for longitudinal data were performed. Results: The alliance rating was high across all informants, with caregivers achieving the highest rating. The average level of cross-informant agreement on the alliance was low between therapists and caregivers (ICC = .26) and moderate between therapists and patients (ICC =.65). A significant contribution of an alliance improvement to the reduction of PTSS over time was found in each of the two tested models: therapists with patients model (b = .682) and therapists with caregivers model (b = .807). However, these effects were not detected with all four perspectives in one comprehensive model. Conclusion: In summary, the potential of caregivers’ views should receive more attention in the therapeutic process of trauma-focused therapy., publishedVersion

Hintergrund: Das Thema Pflege gehört aufgrund des Pflegepersonalmangels bundesweit zu den gesundheitspolitischen Themen mit oberster Priorität. Für die Stadt München lagen bisher keine Daten vor, die eine umfassende und systematische Analyse der Situation der Pflege erlauben. [zum vollständigen Text gelangen Sie über die oben angegebene URL], 18. Deutscher Kongress für Versorgungsforschung (DKVF)

Facile electromodification of metallic NiFe alloys leads to a series of NiFe oxyhydroxide surface films with excellent electrocatalytic performance in alkaline water oxidation. During cyclic voltammetry and after sudden potential jumps between noncatalytic and catalytic potentials, Ni oxidation/reduction was tracked with millisecond time resolution by a UV/Vis reflectance signal. Optimal catalysis at intermediate Ni/Fe ratios is explained by two opposing trends for increasing Fe content: a) pronounced slowdown of the Ni 2+ /Ni 3+ oxidation step and b) increased reactivity of the most oxidized catalyst state detectable at catalytic potentials. This state may involve an equilibrium between Ni 4+ ions and Ni 2+ ions with neighboring ligand holes, possibly in the form of bound peroxides.

Nickel-based catalysts accomplish the direct conversion of urea to pure hydrogen via electrochemical oxidation; yet mechanistic understanding is lacking. Synthesizing a series of carbon fiber paper (CFP) supported Ni(OH)2/MnO2 catalysts, we explored relevant redox transitions and catalysis of both UOR (urea oxidation reaction, in KOH-with-urea) and OER (oxygen evolution reaction, in KOH). Cyclic Voltammetry (CV) in KOH-only solution demonstrated a more cathodic transformation from Ni(III/IV) to Ni(II) compared with that in KOH-with-urea solution. The water oxidation overpotential was shifted to higher values (from 0.48 to 0.53 VRHE) as the Mn:Ni atom ratio increases in CFP-NiMn films. In contrast, a higher Mn content results in higher UOR activity and lower onset potential in KOH solution containing urea (1.395-1.375 VRHE). Quasi in-situ, freeze-quench X-ray absorption spectroscopy (XAS) at the Ni and Mn K-edges was employed to uncover oxidation state changes as well as structural transformations at the atomic level showing that CFP-Ni(OH)2 underwent oxidation state changes by about 1.15 e− and 0.21 e− per Ni ion during OER and UOR processes, respectively, versus only 0.71 e− and 0.07 e− per Ni ion in CFP-NiMn2.4. Mn incorporation can stabilize the Ni in lower valent states in a mixed NiMn catalyst without significant changes in oxidation state and structure. The here investigated, readily synthesized CFP-NiMn films exhibit opposite activity trends in KOH and KOH-with-urea electrolytes: Mn incorporation depresses water oxidation, but it promotes the urea oxidation process. We propose that the water oxidation rate (OER) is positively correlated with the capacity for accumulation of Ni and Mn oxidation equivalents, while the urea oxidation (UOR) rate is negatively correlated with this capacity. Our work offers a mechanistic guideline for designing and synthesizing nonprecious metal-coupled Ni-based catalysts with appropriate redox-properties for urea-oxidation applications.

Porous electrodes for alkaline water electrolysis were prepared by spark plasma sintering, a short-time sintering technique, in combination with a space holder method. After removal of the space holders, highly porous layers of polycrystalline Ni and of a nanocrystalline Ni-Fe alloy were obtained on a metallic substrate. Both porosity and thickness of the electrocatalytic layers can be controlled by the space holder volume content and the sintering process conditions, for example, the applied pressure and temperature. The active surface of the electrode can be increased significantly by a roughness factor of up to 1,120 determined by double layer charging. The porous layers are efficient towards oxygen evolution reaction (OER), whereas activity is greatly influenced by the chemical composition. The porous Ni-Fe electrodes exhibit an extremely low OER-overpotential of 230 mV at 0.3 A cm−2 in highly concentrated KOH (29.9 wt.-%) at 333 K. Beside the high surface area, the efficiency of the porous Ni-Fe layer is characterized by a high intrinsic activity resulting in a low Tafel slope of around 23 mV dec−1 at low and 50 mV dec−1 at high current densities as well as a high turnover frequency (TOF) of approximately 3.4 s−1 at 0.3 V. The porous Ni electrodes have a lower intrinsic activity with higher Tafel slopes and lower TOF. Moreover, an excellent stability and activity under realistic operating conditions of intermittent electrolysis (up to 1 A cm−2) for 100 h was proven for the porous Ni-Fe electrode.

BackgroundThe purpose of this paper was to examine national differences in the desire to participate in decision-making of people with severe mental illness in six European countries.MethodsThe data was taken from a European longitudinal observational study (CEDAR; ISRCTN75841675). A sample of 514 patients with severe mental illness from the study centers in Ulm, Germany, London, England, Naples, Italy, Debrecen, Hungary, Aalborg, Denmark and Zurich, Switzerland were assessed as to desire to participate in medical decision-making. Associations between desire for participation in decision-making and center location were analyzed with generalized estimating equations.ResultsWe found large cross-national differences in patients’ desire to participate in decision-making, with the center explaining 47.2% of total variance in the desire for participation (P < 0.001). Averaged over time and independent of patient characteristics, London (mean = 2.27), Ulm (mean = 2.13) and Zurich (mean = 2.14) showed significantly higher scores in desire for participation, followed by Aalborg (mean = 1.97), where scores were in turn significantly higher than in Debrecen (mean = 1.56). The lowest scores were reported in Naples (mean = 1.14). Over time, the desire for participation in decision-making increased significantly in Zurich (b = 0.23) and decreased in Naples (b = −0.14). In all other centers, values remained stable.ConclusionsThis study demonstrates that patients’ desire for participation in decision-making varies by location. We suggest that more research attention be focused on identifying specific cultural and social factors in each country to further explain observed differences across Europe.

Objective: This study aims to explore relationships between preferred and experienced clinical decision making with service use, and associated costs, by people with severe mental illness. Methods: Prospective observational study of mental healthcare in six European countries: Germany, UK, Italy Hungary, Denmark and Switzerland. Patients (N = 588) and treating clinicians (N = 213) reported preferred and experienced decision making at baseline using the Clinical Decision Making Style Scale (CDMS) and the Clinical Decision Involvement and Satisfaction Scale (CDIS). Retrospective service use was assessed with the Client Socio-Demographic and Service Receipt Inventory (CSSRI-EU) at baseline and 12-month follow-up. Negative binomial regression analyses examined the effects of CDMS and CDIS on service use and inpatient costs at baseline and multilevel models examined these relationships over time. Results: At baseline, staff and patient preferences for active decision making and low patient satisfaction with experienced decisions were associated with longer hospital admissions and higher costs. Patient preferences for active decision making predicted increases in hospital admissions (b = .236, p =.043) over 12 months and cost increases were predicted by low patient satisfaction (b = 4803, p =.005). Decision making was unrelated to medication, outpatient, or community service use. Conclusions: Decision making is related to inpatient service use and associated costs by people with severe mental illness. A preference for shared decision making may reduce healthcare costs via a reduction in inpatient admissions. Patient satisfaction with decisions is a crucial predictor of healthcare costs; therefore, clinicians should maximize patient satisfaction with decision making.

Tb3+ single-and Tb3+/Eu3+ double-doped borate as well as fluorozirconate glasses are investigated for their photoluminescence and energy transfer properties based on the concentration of the dopants. All the double-doped glasses consist of a constant concentration of 0.5 at% Tb3+ ions and an increasing Eu3+ ions concentration, ranging from 0.05 to 0.5 at%. Upon direct excitation of only Tb3+ at 485 nm, the emission spectra of the double-doped glasses demonstrate an enhancement of typical Eu3+ emissions, thus validating the energy transfer from Tb3+ to Eu3+ in both glass systems. While the spectral composition of the emissions of both borate and fluorozirconate glasses are mostly similar, the radiative decay in borate glass is faster than in fluorozirconate glass. The energy transfer efficiency in each glass system is calculated based on the radiative decay measurements. The mechanism of multipolar interaction underlying the energy transfer is determined to be mostly due to dipole-dipole interactions. With increasing Eu3+ concentration, a gradual shift in chromaticity from green to orange/red is observed. Besides the variation in Eu3+ concentration, tunable chromaticity can also be achieved by varying the excitation wavelength.

Tb3+Tb3+ and Eu3+Eu3+ single- and double-doped barium borate glasses are analyzed for their temperature-dependent luminescence and energy transfer properties. The glasses are investigated in the temperature range from 15 K to 700 K. The Tb3+Tb3+ doped glass has a higher temperature stability than the Eu3+Eu3+ doped one. Increasing the temperature leads to an enhanced energy transfer from Tb3+Tb3+ to Eu3+Eu3+ in the double-doped glass. The energy transfer mechanism is investigated in detail.

Background: Clinical decision making (CDM) in the treatment of people with severe mental illness relates to a wide range of life domains. Aims: To examine content of CDM in mental health care from the perspectives of service users and staff and to investigate variation in implementation of decisions for differing content. Method: As part of the European multicenter study clinical decision making and outcome in routine care for people with severe mental illness (ISRCTN75841675), 588 service users and their clinicians were asked to identify the decisions made during their last meeting. Decisions were then coded into content categories. Two months later, both parties reported if these decisions had been implemented. Results: Agreement between patients and staff regarding decision making was moderate (κ = 0.21-0.49; p

Rare-earth doped borate glasses and glass ceramics are investigated for their potential as photon converters. Thermal processing of the as-made glass results in the formation of nanocrystals therein. For optical activation, the glasses are doped with Eu3+ and Tb3+, both enabling an intense emission under ultraviolet excitation. Differential scanning calorimetry and X-ray diffraction are applied to analyze the crystallization behavior. Compared to the undoped glass, the glass transition temperature as well as the crystallization temperature are increased with Eu3+ doping. Upon thermal processing of the as-made glasses, the transmittance is significantly reduced. Preliminary photoluminescence quantum efficiency measurements yield lower values for the glass ceramics.

Sm3+, Eu3+ and Tb3+ doped borate glass is investigated for its potential as light converting phosphor for solid-state lighting applications. Concentration-dependent luminescence, quantum efficiency and radiative lifetimes are analysed. The luminescence quantum efficiency exceeds values of more than 80%. Cross-relaxation processes in the single-doped glasses result in luminescence quenching for Sm3+ with increasing doping level, whereas for Eu3+ and Tb3+ an increase is observed. In Sm3+/Eu3+ and Tb3+/Eu3+ double-doped glass the energy transfer processes between the rare-earth ions are investigated in detail. The colour coordinate of the Tb3+/Eu3+ double-doped glass can be shifted from the green to the red spectral range by changing the Tb3+-to-Eu3+ ratio in favour of Eu3+. In addition, double doping allows for a change in colour coordinate by using different excitation wavelengths.

Background The aim of this study was to develop and evaluate psychometric properties of the Clinical Decision Making Style (CDMS) scale which measures general preferences for decision making as well as preferences regarding the provision of information to the patient from the perspectives of people with severe mental illness and staff. Methods A participatory approach was chosen for instrument development which followed 10 sequential steps proposed in a current guideline of good practice for the translation and cultural adaptation of measures. Following item analysis, reliability, validity, and long-term stability of the CDMS were examined using Spearman correlations in a sample of 588 people with severe mental illness and 213 mental health professionals in 6 European countries (Germany, UK, Italy, Denmark, Hungary, and Switzerland). Results In both patient and staff versions, the two CDMS subscales “Participation in Decision Making” and “Information” reliably measure distinct characteristics of decision making. Validity could be demonstrated to some extent, but needs further investigation. Conclusions Together with two other five-language patient- and staff-rated measures developed in the CEDAR study (ISRCTN75841675) – “Clinical Decision Making in Routine Care” and “Clinical Decision Making Involvement and Satisfaction” – the CDMS allows empirical investigation of the complex relation between clinical decision making and outcome in the treatment of people with severe mental illness across Europe.

Objective: Shared decision-making during the course of treatment is important for people with severe mental illness. However, there is still insufficient knowledge about how people with mental illness view decisions, what kind of decisions are made and how patients experience and perceive the process of participation in routine care. Methods: A qualitative study with focus groups was conducted with patients with chronic mental illness currently receiving outpatient care (N=23). Interviews were audio-taped, transcribed, coded and content analysed. Results: Three main themes were extracted from the data: 1. perception of the clinician and participation, 2. process of communication and flow of information, 3. decisions and transfer. Conclusions: The perception of participation in the decision process depends on a good patient-doctor relationship. Decisions made in the course of an outpatient long-term treatment are complex and are often not made during one single appointment. Frequently, patients seek the advice of people from their social network and/or other health professionals.

Tb3+ and Eu3+ single-doped barium borate glass and ZBLAN glass are investigated for their photoluminescence (PL) and absolute PL quantum efficiency. In addition, both glass systems are characterized with respect to their color stability in the temperature range from 25 degrees C to 400 degrees C. The Tb3+ doped glass shows high color stability over the entire temperature range investigated, whereas the Eu3+ doped glass changes its color appearance with increasing temperature: Eu3+ in ZBLAN glass changes its color appearance from the orange to the red spectral range, whereas the color appearance in borate glass is shifted from the red to the orange-red spectral range.

Rare-earth (RE) doped borate glasses are investigated for their potential as photon down-shifting cover glass for CdTe solar cells. The barium borate base glass is doped with trivalent rare-earth ions such as Sm3+, Eu3+, and Tb3+ showing an intense luminescence in the red (Sm3+, Eu3+) and green (Tb3+) spectral range upon excitation in the ultraviolet and blue. Additionally, the glasses are double-doped with two RE ions for a broad-band absorption. The gain in short-circuit current density of CdTe solar cells with different thicknesses of the CdS buffer layer is calculated. Though the single-doped glasses already reveal a slight increase in short-circuit current density, the double-doped glasses allow for higher efficiency gains since a significant broader spectral range is covered for absorption. For a Tb3+/Eu3+ double-doped glass with a RE doping level of 1 at% each, an efficiency increase of 1.32% can be achieved.

Rare-earth-(RE) doped barium borate glasses are investigated for their potential use as photon downshifting cover glasses for CdTe solar cells and as converters for white light-emitting diodes (LEDs). The glasses are doped with trivalent RE ions such as Eu3+ and Tb3+, resulting in an intense luminescence in the red (Eu3+) and green (Tb3+) spectral range upon excitation in the ultraviolet and blue ranges. Doping the glasses with two different RE ions enables broader absorption, which is necessary for both photovoltaic applications and for the appropriate color mixing needed for use in white LEDs. Though the single-doped cover glasses already reveal a slight increase in the short-circuit current density of CdTe solar cells, the double-doped glasses allow for even higher efficiency gains due to the significantly broader spectral range for absorption. For an Eu3+/Tb3+ double-doped glass with an RE doping level of 1 at.% each, an efficiency increase of 1.32% can be achieved. Furthermore, the Eu3+/Tb3+ double-doped glasses enable appropriate color mixing in the green-to-red spectral range by varying the RE doping level accordingly.

Einleitung und Fragestellung: Die Verfügbarkeit von Informationen zur Patientenvorgeschichte kann im Notfall lebensrettend sein. Nationale und internationale Studien zeigen dementsprechend übereinstimmend, dass medizinische Leistungserbringer dem Austausch notfallmedizinisch relevanter Patienteninformationen[for full text, please go to the a.m. URL], GMDS 2014; 59. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie e.V. (GMDS)