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Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effects of annealing in forming gas 5% hydrogen, 95% nitrogen; FGA) are studied on spin-coated SrBi[SUB2]Ta[SUB2]O[SUB9] SBT thin films. SBT films on a platinum bottom electrode are characterized with and without a platinum top electrode. Films are characterized by residual stress measurements, scanning electron microscopy (SEM), Auger electron spectroscopy (AES), high-temperature X-ray diffraction (HT-XRD) and secondary ion mass spectrometry (SIMS). To determine the degree of strain, lattice constants of Pt are measured by X-ray diffraction (XRD). (HT-XRD) of blanket SBT/Pt/Ti films in forming gas revealed that the bismuth-layered perovskite structure of SBT is stable up to approximately 500 °C. After formation of an intermediate phase between 550 °C and 700 °C, SBT changes its structure to an amorphous phase. SIMS analysis of Pt/SBT/Pt samples annealed in deuterated forming gas 5% D[SUB2], 95% N[SUB2] showed that hydrogen accumulates in the SBT layer and at the platinum interfaces next to the SBT. After FGA of blanket SBT films, tall platinum-bismuth whiskers are seen on the SBT surface. It is confirmed that these whiskers originate from the platinum bottom electrode and grow through the SBT layer. FGA of the entire Pt/SBT/Pt/Ti stack shows two different results. For the samples with a high-temperature annealing (HTA) step in oxygen after top electrode patterning, peeling of the top electrode is observed after FGA. For the samples without a HTA step, no peeling is observed after FGA. The residual stress at room temperature is measured for blanket platinum wafers deposited at different temperatures. It is found that an increase in tensile stress caused by the HTA step in oxygen is followed by a decrease in stress caused by the hydrogen in the forming gas. Without HTA, however, an increase of stress is observed after FGA. [ABSTRACT FROM AUTHOR]

Binary anode electrocatalyst formulations were prepared by adsorption of phthalocyanine and tetraphenylporphyrin complexes of different transition metals on a commercial carbon supported platinum catalyst. Only after pyrolyzing the complexes at 700 °C under nitrogen were catalysts of some activity obtained. A binary Pt/Ni electrocatalyst prepared by this procedure exhibits considerable anodic catalytic activity in the acidic environment of the Nafion® electrolyte for reformate and direct methanol oxidation for more than 400 h without deterioration. Ternary electrocatalyst formulations Pt/Ru/W = 1/1/ y were produced according to the Bönnemann method. The Pt/Ru/W catalyst of 1/1/1.5 (mol/mol/mol) composition is optimal. Compared to the Pt/Ru catalyst, it enhances the performance of reformate (H2 + 150 ppm CO) fuel cells by 50% and of direct methanol fuel cells (steam/methanol vapour = 50:1 mol/mol) by 80%. Attached to a GC electrode by a thin Nafion® film, the catalysts were also tested for methanol oxidation in aqueous methanol solutions in half cells by slow potential stepping. This procedure is useful for fast initial screening. [ABSTRACT FROM AUTHOR]

Phosphoric acid fuel cells (PAFCs) had been developed for cogeneration plants based on natural gas as fuel. Operation of phosphoric acid fuel cells on hydrogen requires recycling of unspent hydrogen from the anode exhaust for obtaining highest efficiency. But recycling rates are limited due to accumulation of inert gases. Theoretical calculations and experimental data on optimizing this operation mode with respect to highest electrical energy efficiency are compared. The results are verified in a 100 cm2 PAFC unit. From the data obtained with a Fuji 2 kW PAFC, the performance of large units with hydrogen recycling is predicted. [ABSTRACT FROM AUTHOR]

The development of a sensitive radioimmunoassay for the determination of lisuride in plasma is described. The antiserum against lisuride-4-hemisuccinate-BSA was raised in rabbits. Using this method the plasma levels of lisuride were monitored following one intravenous (25 µg) and two oral (100 µg and 300 µg) doses of lisuride hydrogen maleate in three female and three male volunteers (intraindividual comparison). The plasma prolactin was also determined by radioimmunoassay. Following i. v. injection, the concentration of lisuride declined in three phases, with half-lives of 5 min, 25 min and 2 h. The total plasma clearance of 800±250 ml × min was in the range of 'plasma flow' through the liver. In agreement with the high rate of biotransformation, the bioavailability of lisuride administered orally was 10%±7% of the 100-µg dose, and 22%±7% of the 300-µg dose. The plasma prolactin was lowered to 3%-18% of its pretreatment value depending on the route of administration and the dose. The reduction appeared to be short-lived and to be directly dependent on the plasma concentration of lisuride. Following intravenous injection, the prolactin level declined after a so far unexplained lagtime of 0.5 h. [ABSTRACT FROM AUTHOR]

Laser desorption followed by jet-cooling allows wavelength-selective as well as mass-selective detection of molecules desorbed from a surface without fragmentation. The cooling characteristics and detection sensitivity of laser desorption jet-cooling of organic molecules are investigated. From the rotational contour of the electronic origin of the S ← S transition of laser-desorbed anthracene, rotational cooling to 5-10 K is demonstrated. Vibrational cooling is studied for laser-desorbed diphenylamine, a molecule with low-energy vibrations, and a vibrational temperature below 15 K is found. The absolute detection sensitivity is determined for the perylene molecule. Using two-color (1+1) resonance enhanced multi-photon ionization (with a measured ionization efficiency of 0.25) for detection, it is found that one ion is produced in the detection region for every 2×10 perylene molecules evaporated from the desorption laser spot. A two-color (1+1) REMPI spectrum (400 points) of perylene is recorded using only 30 picogram of material. [ABSTRACT FROM AUTHOR]

We have investigated the entrainment in a jet expansion of material vaporized with a laser pulse from a surface below but closely adjacent to the jet orifice. Jets of He and Ar were used as carriers, and perylene was the test substance. Its distribution in space and time far from the nozzle was measured by laser-induced fluorescence and one-dimensional imaging with an optical multichannel analyzer. The width of the perylene concentration profile was found to be much narrower than the width of the gas expansion, especially in He. This makes it possible to extract a useful portion of the entrained material through a skimmer. Depending on the values of experimental parameters, the center of the profile first appears above, on, or below the jet axis and then moves lower with time. Effects of several parameters on shape and time-dependent position of the profile were investigated. The results can be used to optimize the overlap of the concentration pulse with a skimmer or other probe. [ABSTRACT FROM AUTHOR]

We have combined the techniques of frequency-modulation spectroscopy (FMS) and photochemical-modulation spectroscopy to carry out high-resolution, high-sensitivity absorption measurements on the formyl and amino radicals. Using the (0,9, 0)-(0,0, 0) band of the Ã, A″- $$\tilde X$$ , A′ transition of HCO at 614 nm, we obtained a sensitivity limit for absorption of 1.5×10. Reconstructed spectra of several HCO lines are presented. [ABSTRACT FROM AUTHOR]

By anodic oxidation of copper sheets in sulfide anion-containing electrolytes copper chalcogenide semiconductor films suitable for photovoltaic applications can be attained. Anodically chalcopyrite (Cu2S) has been formed as pure, mechanically stable, homogeneous and adhesive polycrystalline films, consisting of well-developed large crystallites. Cu2S coated copper sheets were produced with an area of 3cm*3cm. P-n-junctions formed by evaporation of CdS onto the anodically formed Cu2S films show an energy efficiency of 3.3. The extension of this process to ternary systems, like copper/indium/sulfur, is likely to be possible. A mixture of Cu2S and CuInS2 could be formed by codepositing In2S3 together with Cu2S. Cu2Se-films with a thickness of up to 1 mum were formed by chemical bath deposition. [ABSTRACT FROM AUTHOR]

Better performance of and higher electrocatalyst utilization in proton-exchange membrane fuel cells equipped with thin film electrodes is achieved by exploiting pore forming additives in the electrode recipe formulation. Preparing the membrane–electrode assembly by a hot spraying procedure already provides 35% porosity. Additional coarse porosity is obtained by adding pore formers to the electrocatalyst slurry which is used for the hot spraying process. This allows for a better access of oxygen from air to the depth of the cathode. For air operation at ambient pressure and low catalyst loading of 0.15mgPtcm-2 a current density of 200mAcm-2 at 0.7V cell voltage can be obtained with such electrodes. [ABSTRACT FROM AUTHOR]

The potential of electroadsorption/desorption on activated carbon for waste water treatment of industrial effluents is studied. Adsorption isotherms of hydrophobic differently charged model substances on activated carbon were measured in order to obtain specific information about the influence of the charge (+1,−1 and 0) on the adsorbability of comparable, aromatic species and the influence of the bed potential on the adsorption equilibria. In all these cases the adsorption equilibria show a dependence on applied potential in electrolyte of approximately 1m ionic strength. With electrosorption from aqueous solution, a fivefold enhancement of the concentration in one potential controlled adsorption/desorption cycle is achievable. The use of the solvent methanol instead of water for desorption allows for a concentration enhancement by a factor of hundred in the desorptive step. The adsorption capacity of the activated carbon changes only slightly with cycle number. Two cell designs for the performance of potential controlled adsorption/desorption cycles on the large scale are discussed. [ABSTRACT FROM AUTHOR]

Two different processes to prepare smooth* Raney nickel coatings are investigated. Both are based on preparing a precursor coating by gas-phase reaction of nickel at temperatures of around 400°C. Sherardizing of nickel electrodes, that is, reaction with zinc vapour, leads to formation of the γ-phase of Ni–Zn alloy with the approximate composition of 75 to 85wt% Zn (balance: Ni), and gas-phase sulfidizing of nickel electrodes with hydrogen sulfide produces nickel sulfide coatings composed of the phases Ni3S2, αNi7S6 and αNiS. Both types of coating are transformed in situ, the first by caustic leaching and the second during cathodic hydrogen evolution by relatively slow cathodic reduction into smooth, almost closed nanoporous Raney nickel coatings. The comparison of the catalysts from the two different methods reveals the superiority of the second. The hydrogen evolution overpotential is lowest and, during more than 3000h of continuous operation, the catalyst does not deteriorate. Electrodeposited nickel sulfide gives a poorer and less stable RN catalyst than gas phase sulfidized nickel sulfide. [ABSTRACT FROM AUTHOR]

Copyright of Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Naunyn-Schmiedebergs Archiv für Experimentelle Pathologie und Pharmakologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Topical glucocorticosteroids are useful in the treatment of various skin diseases. Although many corticosteroids are available today, there is still a need for highly potent compounds with minimal adverse effects. Methylprednisolone aceponate (MPA) has recently been synthesized. Its activity has been evaluated using the vasoconstrictor assay and the poison ivy test (rhus dermatitis) in 19/20 healthy volunteers of either sex. Comparable blanching was found with MPA in a cream vehicle, in an ointment and a fatty ointment. Vasoconstriction and suppression of experimentallyinduced poison ivy contact dermatitis were dose-dependent in the concentration range 0.01% to 0.5% MPA. Concentrations of MPA of at least 0.05% were significantly active. Following the highest dose, blanching was close to the maximum which can be obtained. This finding, and the improvement of rhus dermatitis, suggest that MPA belongs to the highly potent local glucocorticosteroids. [ABSTRACT FROM AUTHOR]

Copyright of Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)