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The origin of gamma irradiation-induced strong yellow color in brazilianite from Brazil is investigated. The irradiation-induced optical absorption band responsible for the color shows an onset in the blue spectral region at about 2.5 eV and maximum centered in the UV at ~ 4.24 eV. From the ratio between the squared value of the line width (W2) and the peak energy (M), a value of about 0.09 eV is estimated, which is consistent with an absorption band caused by a Schirmer´s-type O− bound small polaron. By electron paramagnetic resonance (EPR), we are able to confirm its microscopic structure. This O− hole center is in fact the Al3+–O−X2+–P5+ hole center already identified by EPR earlier in the literature (where X2+ stands for a nearby divalent cation with negligible abundance of magnetic isotopes). The EPR spectrum of the Al3+–O−X2+–P5+ hole center, along with the O− bound small polaron absorption band responsible for the yellow color, appears simultaneously at high concentrations after gamma irradiation, and vanishes together for thermal annealing above 300 °C, returning after re-irradiation in a reversible way. Their appearance is concomitant with the H0 centers and Ti3+ electron centers, and possible charge-compensating centers. [ABSTRACT FROM AUTHOR]

Renewable and environmentally responsive materials are an energy- and resource-efficient approach in terms of civil engineering applications, e.g. as so-called smart building skins. To evaluate the influence of different environmental stimuli, like humidity or solar radiation, on the long-term actuation behavior and mechanical robustness of these materials, it is necessary to precisely characterize the magnitude and range of stimuli that trigger reactions and the resulting kinetics of a material, respectively, with suitable testing equipment and techniques. The overall aim is to correlate actuation potential and mechanical properties with process- or application-oriented parameters in terms of demand-oriented stimuli-responsive element production. In this study, the impact of solar radiation as environmental trigger on the cellulose-based humidity-sensing material Cottonid, which is a promising candidate for adaptive and autonomously moving elements, was investigated. For simulating solar radiation in the lab, specimens were exposed to short-wavelength blue light as well as a standardized artificial solar irradiation (CIE Solar ID65) in long-term aging experiments. Photodegradation behavior was analyzed by Fourier-transform infrared as well as electron paramagnetic resonance spectroscopy measurements to assess changes in Cottonid's chemical composition. Subsequently, changes in micromechanical properties on the respective specimens' surface were investigated with roughness measurements and ultra-micro-hardness tests to characterize variations in stiffness distribution in comparison to the initial condition. Also, thermal effects during long-term aging were considered and contrasted to pure radiative effects. In addition, to investigate the influence of process-related parameters on Cottonid's humidity-driven deformation behavior, actuation tests were performed in an alternating climate chamber using a customized specimen holder, instrumented with digital image correlation (DIC). DIC was used for precise actuation strain measurements to comparatively evaluate different influences on the material's sorption behavior. The infrared absorbance spectra of different aging states of irradiated Cottonid indicate oxidative stress on the surface compared to unaged samples. These findings differ under pure thermal loads. EPR spectra could corroborate these findings as radicals were detected, which were attributed to oxidation processes. Instrumented actuation experiments revealed the influence of processing-related parameters on the sorption behavior of the tested and structurally optimized Cottonid variant. Experimental data supports the definition of an optimal process window for stimuli-responsive element production. Based on these results, tailor-made functional materials shall be generated in the future where stimuli-responsiveness can be adjusted through the manufacturing process. [ABSTRACT FROM AUTHOR]

GaN epitaxial layers were implanted by 100 keV H ions at different implantation temperatures (LN, RT and 300 °C) with a fluence of 2.5×10 cm. The implanted samples were characterized using Nomarski optical microscopy, AFM, XRD, and TEM. Topographical investigations of the implanted surface revealed the formation of surface blistering in the as-implanted samples at 300 °C and after annealing at higher temperature for the implantation at LN and RT. The physical dimensions of the surface blisters/craters were dependent on the implantation temperature. XRD showed the dependence of damage-induced stress on the implantation temperature with higher stress for the implantation at 300 °C. TEM investigations revealed the formation of a damage band in all the cases. The damage band was filled with large area microcracks for the implantation at 300 °C, which were responsible for the as-implanted surface blistering. [ABSTRACT FROM AUTHOR]

Organic microcavities offer tantalizing prospects for studying the interactions of light and matter. For electrical excitation of these processes, electrodes must be integrated. However, the large absorption properties of metals are generally considered fatal for optical coherence. With this in mind, we embedded a thin silver grating into an organic microcavity to generate periodic arrays of localized cavity modes and metal-based Tamm plasmon polaritons. These excited states are capable of phase coupling across the grating. At room temperature and under non-resonant pumping, we selectively stimulated coherent emission from in- and out-of-phase locked arrays. We show that an absorptive metal inside an optical cavity is compatible with coherent emission. Most importantly, the inherently low residual absorption of the organic layer enables coherence to spread over macroscopic distances, even at room temperature. Our strategy of embedding metal patterns into an organic microcavity yields a viable route towards electrically driven organic solid-state lasers. [ABSTRACT FROM AUTHOR]

The HYPER-MUCHFUSS (HYPER-velocity stars or Massive Unseen Companions of Hot Faint Underluminous Stars from SDSS) project targets a population of high-velocity subluminous B stars to discover either close binaries with massive unseen companions or hyper-velocity stars. We re-observed high-velocity subdwarf selected candidates from the SDSS spectroscopic Data Release 6. Starting in 2007 we used several instruments and have now reached a completion level of 33% (from 265 targets), whereas we found at least 16 close binaries. Here we present results for two of our 39 hyper-velocity star candidates. From the available Digitized Sky Surveys photographic plates we measured a significant proper motion for 14 stars. Combining this information with a detailed spectroscopic analysis allows for the first time a complete determination of the 3D-trajectories for a high-velocity sample. We present our preliminary results for the two subdwarfs J1644+4523 and J1211+1437. Assuming the Standard Allen and Santillan (Rev. Mex. Astron. Astrofis. 22:255, ) potential the first one is bound and originates in the central region of the Galaxy. The subdwarf B star J1211+1437 is possibly unbound and seems to originate in the Galactic rim. We also performed numerical kinematical experiments with increased dark matter halo mass. and found that the origin of J1644+4523 in the central region is not changed but the time-of-flight is drastically shortened. J1211+1437 would be bound and probably belongs to population II. [ABSTRACT FROM AUTHOR]

The HYPER-MUCHFUSS project targets a population of high velocity subluminous B stars to discover either close binaries with massive unseen companions or hyper-velocity stars. Our starting point is the enormous database of SDSS. We preselected sdO/B candidates by colour and classified them by visual inspection of their spectra. We measured the radial velocity from the coadded SDSS spectra, which serves as first epoch measurement. Stars with high Galactic rest-frame velocities were selected and second epoch observations were obtained starting in 2007 at several sites. For the brighter targets we also included the SDSS individual spectra as additional information. In the course of our survey we observed 88 out of 265 stars from our target list. We discovered 39 HVS candidates as well as 49 close binaries. In addition we analysed all single spectra of sdBs from SDSS and found 120 close binaries. For the targets with constant RVs we performed a proper motion analysis with the highest possible accuracy from the available digitised photographic plates. Together with the analysed spectra and the calculation of the spectroscopic distance, we calculated complete trajectories and deduced the origins of these stars. Targets with high RV variability on short timescales were selected for follow-up. Numerical simulations based on the period and companion mass distribution of the known sdB binary sample were carried out to optimise the target selection and single out candidate binaries with massive companions. The follow-up campaign using WHT/ISIS and CAHA-3.5m/TWIN started in 2009. [ABSTRACT FROM AUTHOR]

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A Frenkel exciton model is applied to ultrathin films of PTCDA confined between layers of a material with electronic transitions in a different energetic region. This model accounts for the elongation of an effective internal vibration in the relaxed excited geometry of a molecule and for the transfer of an electronic excitation between different molecular sites. The comparison of the model calculations with experimental findings reveals that due to the modified conditions at the organic interfaces, boundary layers of the PTCDA films show blue-shifted transition energies with respect to inner molecular layers surrounded by the same material. The resulting changes of the lowest vibronic subband contribute further to the distinct absorption line shapes. [ABSTRACT FROM AUTHOR]

The acetabular cup position after total hip arthroplasty (THA) regarding its inclination and version angles are influential parameters concerning the postoperative range of motion and dislocation stability. Standard anterior-posterior X-rays remain an important diagnostic instrument to observe the postoperative outcome and to secure quality control after THA, where an optimal positioning of the patient is recommended when taking these X-rays. The purpose of this preliminary study was to determine the effect of pelvic tilting regarding the positioning calculation of the acetabular cup from standard radiographs using a modified method according to Pettersson et al. (Acta Radiol Diagn, 23:259–263, ). In our model experiment, we were able to show that pelvic tilting to either side causes a considerable difference between the radiographic and calculated version angles following approximately linear functions. However, pelvic tilting to either side, leads, regarding the calculation of the inclination, to an average deviation between radiographic and calculated inclination angles less than 2°. [ABSTRACT FROM AUTHOR]

A metal-oxide-semiconductor structure containing a single layer of size-controlled silicon nanocrystals embedded into gate oxide was fabricated. Size control for the silicon nanocrystals was realized by using a SiO2/SiO/SiO2 layer structure with the embedded SiO layer having the thickness of the desired Si nanocrystals and using a high-temperature annealing for forming the silicon nanocrystals. Current-voltage, capacitance-voltage, and conductance-voltage characteristics were measured for a sample containing 4-nm-sized crystals. From the Fowler-Nordheim plot an effective barrier height of 1.6 eV is estimated for our silicon nanocrystals. Electron trapping, storing, and de-trapping in silicon nanocrystals were observed by capacitance-voltage and conductance-voltage measurements. The charge density was measured to be 1.6×1012 /cm2, which is nearly identical to the silicon-nanocrystal density measured approximately via a transmission electron microscopy image. Conductance measurements reveal a very low interface charge of our structure. [ABSTRACT FROM AUTHOR]

A low-temperature (550 °C) catalyst-free route has been applied to fabricate ZnO nanoneedles and nanosaws via evaporation of metallic Zn powder. The nanoneedles are vertically aligned on GaN(0001)/Si(111) substrates. Based on electron-microscopy observations, we postulate that the needles grew from the closely stacked ZnO columnar grains, which were formed with <0001> texture in an early stage. The uniquely shaped ZnO nanosaws were found in a large quantity under a similar low-temperature growth condition. In addition, single-crystalline micrometer saws were also obtained under an increased Zn vapor supersaturation by changing the sample configuration. [ABSTRACT FROM AUTHOR]

Epitaxial BaTiO3 films and epitaxial BaTiO3/SrTiO3 multilayers were grown by pulsed laser deposition on vicinal surfaces of (001)-oriented Nb-doped SrTiO3 (SrTiO3?:?Nb) single-crystal substrates. Atomic force microscopy was used to investigate the surface topography of the deposited films. The morphology of the films, of the BaTiO3/SrTiO3 interfaces, and of the column boundaries was investigated by cross-sectional high-resolution transmission electron microscopy. Measurements of the dielectric properties were performed by comparing BaTiO3 films and BaTiO3/SrTiO3 multilayers of different numbers of individual layers, but equal overall thickness. The dielectric loss saturates for a thickness above 300 nm and linearly decreases with decreasing film thickness below a thickness of 75 nm. At the same thickness of 75 nm, the thickness dependence of the dielectric constant also exhibits a change in the linear slope both for BaTiO3 films and BaTiO3/SrTiO3 multilayers. This behaviour is explained by the change observed in the grain morphology at a thickness of 75 nm. For the thickness dependence of the dielectric constant, two phenomenological models are considered, viz. a ‘series-capacitor’ model and a ‘dead-layer’ model. [ABSTRACT FROM AUTHOR]

The present paper investigates the interface trap density of a new high-? gate dielectric stack, La2Hf2O7/SiO2 on Silicon. Amorphous La2Hf2O7 thin films are deposited by metal evaporation in the presence of atomic oxygen beams on an ultra-thin SiO2 layer (1.5 nm) grown by rapid thermal oxidation on a p-type Si substrate. A combination of electrical (C-V) and cross sectional TEM measurements indicates a value of the dielectric constant ? of about 19±2.2. The interface states density (Dit) was measured using the conductance method for different La2Hf2O7 thicknesses ranging from 3 nm to 14 nm. Dit ranges from 3.4×1010 eV-1? cm-2 to 4.8×1012 eV-1? cm-2 and shows a quasi-linear dependence on the La2Hf2O7 layer thickness. The interface state density increase with film thickness could have different explanations, such as oxygen de-passivation and/or defect generation at the Si-SiO2 interface, formation of a new Si-SiO2 interface by Si oxidation or alternatively, the SiO2 interfacial layer reduction by oxygen vacancies. [ABSTRACT FROM AUTHOR]

We report multi-layer ZnO nanosheets obtained by annealing Zn polyhedral particles in pure O2. The structure comprises a cluster core with side faces terminated with 50-nm-thick multi-layer sheets. The nanosheets were found to be (0001)-oriented single-crystalline wurtzite ZnO. By studying the early growth stages, it appears that the sheets form through a ripening process of dendritic ZnO nanostructures, during which the single-crystalline nature and crystallographic orientation are conserved. The ripening is promoted by the rapid oxidation of the Zn polyhedral microcrystals. We also show that appropriate modification of the oxidation process leads to the formation of well-defined dendritic nanowires. The optical properties (photoluminescence and Raman) of these nanostructured materials are discussed. [ABSTRACT FROM AUTHOR]

Dislocation structures of interfaces between bonded (001) Si wafers with co-existing low-angle twist and tilt misorientations were studied by transmission electron microscopy. At dominating twist a square screw dislocation network accommodates the twist and interacts with steps at the interface, forming 60-degree dislocations. As the step density, i.e., the tilt angle, increases relative to the twist angle, the density of so-called zigzag reactions increases. Finally, hexagonal dislocation meshes dominate the dislocation configuration. It was found that the plan-view observations give the crystallographic relations accurately. The structures of the dislocation configurations were analyzed using Bollmann's dualistic representation. The rotation axes and angles were determined. [ABSTRACT FROM AUTHOR]

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Abstract. The distribution and annealing behavior of defects in crystalline silicon caused by 7 x 10[sup 16]/cm[sup 2] He[sup +] implantation were investigated by slow-positron annihilation technique, transmission electron microscopy, Rutherford backscattering, and channeling spectroscopy. It was found that small vacancy clusters were induced in the surface region and big clusters (microbubbles) formed around the projected range in which the crystal was heavily damaged by the implantation. The small vacancy clusters in the near-surface region start to disappear at 300 Celsius and can be removed at temperatures up to 700 Celsius by dissociation and diffusing to the damaged region. This results in the growth of voids. The severely damaged region around the projected range begins to anneal out at temperatures higher than 600 Celsius, and He is released, leaving voids embedded inside the crystalline silicon. [ABSTRACT FROM AUTHOR]

Abstract. Chemical vapor deposition (CVD) carbonization experiments were carried out on (100) silicon substrates. Scanning and transmission electron microscopy (SEM and TEM) were used to detect and characterize the interlace defects. Conditions for preventing the formation of micropipes and voids at the SiC/Si interfaces were found. [ABSTRACT FROM AUTHOR]

The microstructure of β-SiC/Si(100) interfaces generated by carbonization and subsequent growth in a chemical vapor deposition (CVD) reactor was investigated by transmission electron microscopy (TEM). Differently prepared cross section and planar specimens allowed a detailed characterization of interface defects. Besides pyramidal voids, which were frequently reported to appear at SiC/Si interfaces within the substrate, recently discovered micropipes are of special interest. Both kinds of defects form by outdiffusion of silicon during the carbonization process. In contrast to voids. which initially remain empty, micropipes develop by simultaneous ingrowth of SiC. The area densities of micropipes were found to be orders of magnitude higher than those of voids. Micropipe formation may be due to a high density of SiC nuclei preexisting on the substrate surfaces after pretreatments. The simultaneous development of voids and micropipes is discussed on the basis of results obtained from a short-time carbonization experiment. [ABSTRACT FROM AUTHOR]

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The genetically obese Zucker rat (fa/fa) is an animal model with severe insulin resistance of the skeletal muscle. We investigated whether a defect of insulin-dependent glucose transporter (GLUT 4) translocation might contribute to the pathogenesis of the insulin-resistant state. fa/fa rats, lean controls (Fa/Fa) as well as normal Wistar rats were injected intraperitoneally with insulin and were killed after 2 or 20 min, respectively. Subcellular fractions were prepared from-hind-limb skeletal muscle and were characterized by determination of marker-enzyme activities and immunoblotting applying antibodies against α1 Na/K AT Pase. The relative amounts of GLUT 1 and GLUT 4 were determined in the fractions by immunoblotting with the respective antibodies. Insulin induced an approximately two-fold increase of GLUT 4 in a plasma membrane and transverse tubule enriched fraction and a decrease in the low density enriched membrane fraction in all three groups of rats. There was a high individual variation in GLUT 4 translocation efficiency within the groups. However, no statistically significant difference was noted between the groups. No effect of insulin was detectable on the distribution of GLUT 1 or α1 NaK ATPase. The data suggest that skeletal muscle insulin resistance of obese Zucker rats is not associated with a lack of GLUT 4 translocation. [ABSTRACT FROM AUTHOR]

The spontaneous hypertensive rat is an animal model characterized by a syndrome of hypertension, insulin resistance and hyperinsulinaemia. To elucidate whether in analogy to other insulin resistant animal models an inactivity of the insulin receptor kinase or an alteration of the glucose transporter (GLUT 4) level in the skeletal muscle might contribute to the pathogenesis of insulin resistance we determined insulin receptor kinase activity and GLUT 4 level in the hindlimbs of spontaneous hypertensive rats and normotensive control rats. Normotensive normoinsulinaemic Lewis and Wistar rats were used as insulin sensitive controls, obese Zucker rats were used as an insulin resistant control with known reduced skeletal muscle insulin receptor kinase activity. Binding of I-insulin, crosslinking of I-B-insulin, autophosphorylation in vitro with P-ATP and phosphorylation of the synthetic substrate Poly (Glu 4: Tyr 1) were performed after partial purification of solubilized receptors on wheat germ agglutinin columns. GLUT 4 levels were determined by Western blotting of subcellular muscle membranes. Insulin receptors from spontaneous hypertensive rats compared to those from Lewis and Wistar rats showed no difference of the binding characteristics or the in vitro auto- and substrate phosphorylation activity of the receptor, while in the Zucker rats the earlier described insulin receptor kinase defect was clearly evident. Western blots of subcellular muscle membrane fractions with antibodies against GLUT 4 revealed no difference in transporter levels. These data suggest that insulin resistance in spontaneous hypertensive rats is caused neither by an insulin receptor inactivity nor by a decreased number of glucose transporters in the skeletal muscle. [ABSTRACT FROM AUTHOR]

A mixed finite element method for second order problems is considered. Optimal L -error estimates for the elliptic as well as for the corresponding parabolic problem are derived. [ABSTRACT FROM AUTHOR]

In order to take the conditions of natural Herpes simplex virus (HSV) infection into consideration, the genetic resistance of C57-B1 mice, which was established by intraperitoneal HSV-1 infection [Lopez, 1975], was investigated in vaginally infected mice. The course of infection in the mucous membranes did not differ in sensitive (NMRI) and resistant (C57-B1) mice: both number of takes and virus elimination from the vagina were equal, and no difference in viral titer produced in the vagina was detected. Viral titer in the productively infected lumbosacral ganglia, however, was less in the resistant mice. An experiment with foot-pad-infected mice confirmed that the number of productively infected ganglia was reduced in resistant mice, and contralateral ganglia were infected only in the sensitive mouse strain. In spite of this, the number of latently infected animals did not vary significantly in the mouse strains. Higher activity of defense mechanisms in resistant mice, apparently localized in the ganglia, resulted in reduced lethality. As to the mechanisms of the resistance, neither antibody nor interferon response were enhanced in C57-B1 mice, but resistance was abolished by depletion of several cellular functions, i.e., lymphocytes by cyclophophamide or X-rays, macrophages by silica or macrophage-antiserum, and M-cells bySr. [ABSTRACT FROM AUTHOR]

The forward current-voltage characteristics of PtSi Schottky contacts on epitaxial n-type Si (111) is studied in the temperature range from 100 to 300 K. A current contribution in excess to that predicted by thermionic emission diffusion theory is caused by a few thousand patches of reduced Schottky barrier height in a device area of 3.14 mm. The typical lateral extent of these patches is 70-250 nm. It correlates with the size of surface bumps observed. The number of patches is reduced upon increasing the silicidation temperature up to T=550°C. Possible non-uniformities of the typical crystallite grain size of 20 nm are not resolved due to effective pinch-off. [ABSTRACT FROM AUTHOR]

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Copyright of Deutsche Zeitschrift für die Gesamte Gerichtliche Medizin 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.)

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A technique of direct bonding wafers up to 6-inch diameter without mechanical load after being heated to elevated temperatures in H2 or in non-flammable forming gas (5% H2/95% N2) was applied to GaAs and GaAs/GaP. Electron microscopy revealed crystallographic bond interfaces containing the typical dislocation network. The density of dislocations can be easily chosen below a limit adverse to electrical properties. Current–voltage characteristics of doped GaAs wafer pairs showed ohmic behavior of p–p and n–n junctions, whereas p–n diodes showed 2 to 3 V breakdown voltage as well as an ideality factor between 1.0 and 1.8. [ABSTRACT FROM AUTHOR]

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Abstracts are not published in this journal [ABSTRACT FROM AUTHOR]

A hydrogeological study has been carried out in Antalya travertine basin for the future domestic water supply of Antalya. Geological formations that could be used as an aquifer have been identified, and a hydrogeological map has been prepared. Water-quality analyses show that groundwater has been and is being contaminated by sewage discharge,industrial works, and other activities that create an ever-expendingimpact to the only available aquifer. Something should be done immediately to protect the aquifer from additional degradation. [ABSTRACT FROM AUTHOR]