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Hintergrund: ERAS® (Enhanced Recovery After Surgery) beschreibt ein multimodales, interdisziplinäres und interprofessionelles Behandlungskonzept, welches die postoperative Rekonvaleszenz des Patienten durch den Einsatz evidenzbasierter Maßnahmen optimiert. Ziel der Arbeit: Ziel dieses Artikels ist es, die Erfahrungen unseres von der ERAS® Society für kolorektale Resektionen zertifizierten Zentrums 18 Monate nach erfolgreicher Implementierung darzulegen. Material und Methoden: Seit Beginn der Zertifizierung wurden in unserer Klinik 261 Patienten nach den Vorgaben des ERAS®-Konzeptes behandelt. Als Vergleichsgruppe wurden die letzten 50 Patienten vor Beginn der Implementierung hinsichtlich der Compliance an ERAS®-Vorgaben, Liegedauer im Krankenhaus und Wiederaufnahmerate, der Notwendigkeit der Betreuung auf einer Intensiv- oder Intermediate-Care-Station, Anzahl notwendiger Reoperationen und Komplikationsrate ausgewertet. Ergebnisse: Die Compliance ist von 39,3 % vor der ERAS®- (Prä-ERAS) auf 81,1 % nach der ERAS®-Implementierung gestiegen (p< 0,001). Zeitgleich trat eine Reduktion der Liegedauer von 7 Tagen Prä-ERAS® auf 5 Tage bei den ERAS®-Patienten auf (p= 0,001). Während die Rate an chirurgischen Komplikationen zwischen beiden Gruppen gleich war (p= 0,236), traten nichtchirurgische Komplikationen in der ERAS®-Kohorte signifikant seltener auf (p= 0,018). Diskussion: Es gibt gut bekannte Stolpersteine in der Implementierung und Aufrechterhaltung eines ERAS®-Konzeptes. Es lohnt sich allerdings im Sinne des Patienten, diese zu umschiffen und ERAS® als Standardbehandlungspfad zu etablieren.

Hintergrund: ERAS® (Enhanced Recovery After Surgery) beschreibt ein multimodales, interdisziplinäres und interprofessionelles Behandlungskonzept, welches die postoperative Rekonvaleszenz des Patienten durch den Einsatz evidenzbasierter Maßnahmen optimiert. Ziel der Arbeit: Ziel dieses Artikels ist es, die Erfahrungen unseres von der ERAS® Society für kolorektale Resektionen zertifizierten Zentrums 18 Monate nach erfolgreicher Implementierung darzulegen. Material und Methoden: Seit Beginn der Zertifizierung wurden in unserer Klinik 261 Patienten nach den Vorgaben des ERAS®-Konzeptes behandelt. Als Vergleichsgruppe wurden die letzten 50 Patienten vor Beginn der Implementierung hinsichtlich der Compliance an ERAS®-Vorgaben, Liegedauer im Krankenhaus und Wiederaufnahmerate, der Notwendigkeit der Betreuung auf einer Intensiv- oder Intermediate-Care-Station, Anzahl notwendiger Reoperationen und Komplikationsrate ausgewertet. Ergebnisse: Die Compliance ist von 39,3 % vor der ERAS®- (Prä-ERAS) auf 81,1 % nach der ERAS®-Implementierung gestiegen (p< 0,001). Zeitgleich trat eine Reduktion der Liegedauer von 7 Tagen Prä-ERAS® auf 5 Tage bei den ERAS®-Patienten auf (p= 0,001). Während die Rate an chirurgischen Komplikationen zwischen beiden Gruppen gleich war (p= 0,236), traten nichtchirurgische Komplikationen in der ERAS®-Kohorte signifikant seltener auf (p= 0,018). Diskussion: Es gibt gut bekannte Stolpersteine in der Implementierung und Aufrechterhaltung eines ERAS®-Konzeptes. Es lohnt sich allerdings im Sinne des Patienten, diese zu umschiffen und ERAS® als Standardbehandlungspfad zu etablieren.

Resistance to soil-borne viruses as Soil-borne Wheat Mosaic Virus (SBWMV) has gained evident importance in wheat research and breeding. Very few varieties of bread and durum wheat are resistant to these viruses. Search for new sources of SBWMV is conducted worldwide and loci causing resistance have been described on the B and D genomes of tetraploid and hexaploid wheat. In the present study, a gene locus was identified on the A genome of Triticum monococcumand was successfully transferred to hexaploid wheat. In hexaploid wheat, it is expressed in a stable dominant manner. As this is the first SBWMV resistance gene located on the A genome, this locus is proposed as Sbm3.

The extension of transient grating spectroscopy to the x-ray regime will create numerous opportunities, ranging from the study of thermal transport in the ballistic regime to charge, spin, and energy transfer processes with atomic spatial and femtosecond temporal resolution. Studies involving complicated split-and-delay lines have not yet been successful in achieving this goal. Here we propose a novel, simple method based on the Talbot effect for converging beams, which can easily be implemented at current x-ray free electron lasers. We validate our proposal by analyzing printed interference patterns on polymethyl methacrylate and gold samples using ∼3  keV X-ray pulses.

We describe the design, development, and performance of HAWK-I, the new High-Acuity Wide-field K-band Imager for ESO's Very Large Telescope, which is equipped with a mosaic of four 2 k $\times$2 k arrays and operates from 0.9-2.4 μm over $7.5\arcmin \times 7.5\arcmin$with 0.1´´ pixels. A novel feature is the use of all reflective optics that, together with filters of excellent throughput and detectors of high quantum efficiency, has yielded an extremely high throughput. Commissioning and science verification observations have already delivered a variety of excellent and deep images that demonstrate its high scientific potential for addressing important astrophysical questions of current interest.

Les intoxications médicamenteuses volontaires (IMV) sont une situation fréquente en régulation médicale et en Smur. Plusieurs études semblent indiquer que la régulation médicale des IMV n’est pas performante. Nos objectifs étaient d’étudier les Smur de seconde intention en tant que critère de qualité de la régulation et d’identifier les facteurs de risque de Smur de seconde intention. Étude rétrospective, monocentrique, du 1erjanvier 2008 au 31 décembre 2010. Les patients majeurs pris en charge en Smur pour IMV et admis dans un hôpital universitaire étaient inclus. Une analyse univariée puis une régression logistique multiple étaient planifiées pour comparer les données épidémiologiques et toxicologiques entre les patients bénéficiant de l’envoi immédiat ou secondaire d’une ambulance médicalisée. Trois cent douze patients étaient inclus dont 69 % de femmes. L’âge médian était de 45 [35; 53] ans. Le Smur était envoyé en première intention pour 131 patients (41 %). Les patients pris en charge secondairement par un Smur étaient plus souvent intubés (n= 67 [47 %] vs n= 111 [61 %], p= 0,001) et admis en réanimation (n= 87 [66 %] vs n= 147 [81 %], p= 0,001). Aucun critère épidémiologique ou toxicologique n’était un facteur de risque de Smur de seconde intention. Le Smur est secondairement déclenché dans plus de la moitié des IMV et est associé à des mesures de réanimation plus fréquentes. Les décisions d’envoi du Smur en seconde intention ne sont pas expliquées par des critères épidémiologiques ou toxicologiques. Acute drug self-poisoning (DSP) is frequently encountered in emergency medical services. Previous studies seem to show that poisoning dispatch is not efficient. Our aim was to investigate secondary dispatch of mobile intensive care units (MICUs) as a criterion of quality and we also wanted to identify factors associated with secondary dispatch. We conducted a retrospective and monocentric study from 01 January 2008 to 31 December 2010.We included DSP patients who benefitted from a MICU dispatch.We compared epidemiological (age, gender, co-morbidities) and toxicological (drug class and supposed ingested dose) data between patients who were immediately treated by a MICU team and patients for whom a MICU was secondarily dispatched upon the request of first-responders. Variables significantly different between groups were then included in a multiple regression analysis. Three hundred and twelve DSP patients were included with 69% of women and a median age of 45 years [35; 53]. A MICU team was immediately dispatched for 131 patients (41%). Patients with a secondary MICU dispatch were more frequently intubated (N = 67 [47%] vs N = 111 [61%], P = 0.001) and admitted to an intensive care unit (N = 87 [66%] vs N = 147 [81%], P = 0.001). Epidemiological and toxicological data were not different between groups. A MICU is secondarily dispatched in more than 60% of severe DSP cases. Secondary dispatch is associated with an increased risk of intensive treatment. Toxicological and epidemiological data do not explain secondary dispatch.

In this paper two case studies, highlighting the role of the integrated modeling in the performance prediction and requirement verification of the E-ELT are presented. First example discusses the effect of the local wind load on the secondary mirror and the global wavefront error. Analysis and simulations showed that such local effect is one of the main contributors to the telescope error budget. A detailed modeling and simulation approach with the possibility to modify some important mechanical and control parameters led to a better understanding of the problem and searching for appropriate mitigation strategies. In the second example the effect of friction devices of the lateral support of the azimuth structure is presented. Such devices were originally proposed by the telescope structure contractor to reduce the induced stresses and force due to the temperature variations. A detailed modeling of the friction devices and its inclusion into the telescope dynamical model revealed that some performance and interface requirements are violated.

In order to evaluate the telescope performance and to derive error budget and stroke allocations a ray-tracing and performance analysis toolkit was developed at the European Southern Observatory (ESO) during project Phase B. Performance estimates and individual error and stroke budget allocations are derived by analyzing the impact of a defined set of perturbations at sub - system level after propagation through a model of the wavefront control. The ray-tracing and performance analysis toolkit is used in parallel to other modeling activities such as structural, control and detailed adaptive optics modeling and provides interfaces to any of those. The ray-tracing and performance analysis toolkit consists of a set of models each suitable for analyzing sub-systems at a specific temporal and spatial frequency. The impact of quasi - static and dynamic loads is computed by implementing finite element model (FEM) and control model analysis results in optical models which either use linear optical sensitivities or ray - tracing at different levels of resolution.

The centralized system approach for computer and telecommunication network management has been presenting scalability problems along with the growth in the amount and diversity of managed equipment. Moreover, the increase in complexity of the services being offered through the networks also contributes to adding extra workload to the management station. The amount of data that must be handled and processed by only one administration point could lead to a situation where there is not enough processing and storage power to carry out an efficient job. In this work we present an alternative approach by creating a highly distributed computing environment through the use of Grids of autonomous agents to analyze large amounts of data, which reduce the processing costs by optimizing the load distribution and resource utilization. Copyright © 2004 John Wiley & Sons, Ltd.

We report on rapid in situanalysis of liquid metal melts under reduced ambient pressure by laser-induced breakdown spectroscopy (LIBS) using a transportable system. LIBS denotes a method in which characteristic optical emission line intensities of excited species in laser-generated plasma plumes are used for a quantitative chemical analysis of target materials. It is a fast, noncontact method that can be carried out under various atmospheric conditions, allowing large working distances between the sample under investigation and the detection system. For these reasons, LIBS is applicable in particular for process control in metallurgy under reduced ambient pressure. This was demonstrated for two types of vacuum devices under production conditions at a steel mill. The results of these experiments, including calibration curves for Cr, Ni, and Mg in liquid steel, are presented. The influence of variations in the ambient pressure on the results of the LIBS analysis is discussed within the frame of a generalized shock-wave model for the expansion of the laser-induced plasma plume.

Die aus kontrollierten randomisierten Studien gewonnenen Erkenntnisse haben zu einer weiten Verbreitung der adjuvanten endokrinen, zytostatischen oder chemoendokrinen Therapie geführt. Auch für die günstigsten Tumorstadien kann bei positivem Hormonrezeptorstatus eine endokrine Therapie empfohlen werden. Die 8. Konsensuskonferenz in St. Gallen über die Behandlung des Mammakarzinoms 2003 hat eine Vielfalt an Therapieoptionen für fast alle Patientinnen eröffnet. Schwerpunkte waren die Option einer adjuvanten Anastrozoltherapie für Frauen mit Tamoxifenkontraindikationen oder -unverträglichkeit und die Definition einer Gruppe «stärkerer» Chemotherapien für Hochrisikopatientinnen. Leider hat das Expertengremium keine klaren Empfehlungen abgegeben, weder für die Auswahl idealer Kandidatinnen für die reine endokrine Therapie (als Therapieoption für alle Patientinnen mit optimaler «endocrine responsiveness» oder Kontraindikationen gegen Chemotherapie) noch für die aggressiveren Therapieformen. In der Zwischenzeit haben neue oder aktualisierte Studien nützliche Zusatzinformationen für die gemeinsame Entscheidungsfindung mit den Patientinnen geliefert. Die kanadische MA.17-Studie zeigte einen signifikanten Vorteil durch eine Sequenztherapie mit Letrozol nach 5 Jahren Tamoxifen gegenüber nur 5 Jahren Tamoxifen. Zusammen mit aktualisierten Daten der ATAC-Studie und der italienischen ITA-Studie wird die Rolle der Aromataseinhibitoren als adjuvante Therapie kontinuierlich gestärkt. Einige Studien zeigten signifikante Vorteile bezüglich Rezidivfreiheit und/oder Überleben durch eine taxanhaltige Therapie im Vergleich mit einer taxanfreien Therapie. Diese Daten sollten Patientinnen unbedingt zugänglich gemacht werden. Im komplexen Prozess der Entscheidungsfindung sind ein umfassendes Wissen über die Studienlage und die frühe Einbeziehung der Patientin notwendig.

ZusammenfassungDie aus kontrollierten randomisierten Studien gewonnenen Erkenntnisse haben zu einer weiten Verbreitung der adjuvanten endokrinen, zytostatischen oder chemoendokrinen Therapie geführt. Auch für die günstigsten Tumorstadien kann bei positivem Hormonrezeptorstatus eine endokrine Therapie empfohlen werden. Die 8. Konsensuskonferenz in St. Gallen über die Behandlung des Mammakarzinoms 2003 hat eine Vielfalt an Therapieoptionen für fast alle Patientinnen eröffnet. Schwerpunkte waren die Option einer adjuvanten Anastrozoltherapie für Frauen mit Tamoxifenkontraindikationen oder -unverträglichkeit und die Definition einer Gruppe «stärkerer» Chemotherapien für Hochrisikopatientinnen. Leider hat das Expertengremium keine klaren Empfehlungen abgegeben, weder für die Auswahl idealer Kandidatinnen für die reine endokrine Therapie (als Therapieoption für alle Patientinnen mit optimaler «endocrine responsiveness» oder Kontraindikationen gegen Chemotherapie) noch für die aggressiveren Therapieformen. In der Zwischenzeit haben neue oder aktualisierte Studien nützliche Zusatzinformationen für die gemeinsame Entscheidungsfindung mit den Patientinnen geliefert. Die kanadische MA.17-Studie zeigte einen signifikanten Vorteil durch eine Sequenztherapie mit Letrozol nach 5 Jahren Tamoxifen gegenüber nur 5 Jahren Tamoxifen. Zusammen mit aktualisierten Daten der ATAC-Studie und der italienischen ITA-Studie wird die Rolle der Aromataseinhibitoren als adjuvante Therapie kontinuierlich gestärkt. Einige Studien zeigten signifikante Vorteile bezüglich Rezidivfreiheit und/oder Überleben durch eine taxanhaltige Therapie im Vergleich mit einer taxanfreien Therapie. Diese Daten sollten Patientinnen unbedingt zugänglich gemacht werden. Im komplexen Prozess der Entscheidungsfindung sind ein umfassendes Wissen über die Studienlage und die frühe Einbeziehung der Patientin notwendig.

The photoinduced change of electrical conductivity and dielectric function were investigated in porous silicon and porous TiO2 by means of Complex Transient Microwave Photoconductivity Method. In porous TiO2, the photoexcitation leads to the increase of the dielectric function. The amplitude of this increase depends strongly on the size of the nanoparticles. The sign of the photoinduced change of the dielectric function is negative for mesoporous silicon and positive for nanoporous silicon. The photoinduced increase of the dielectric function in porous TiO2 is explained by the spatial separation of photoexcited charge carriers inside one nanoparticle while the interparticle transitions have very small probability during one microwave half period. In porous silicon, the confinement of charge carriers depends on the porosity. Therefore, the positive photoinduced change of the dielectric function is observed only in nanoporous silicon where most of photoexcited carriers are strongly localized.

Electro-chemical etching of heavily doped, (110) oriented, p⁺ (boron) doped silicon wafers results in porous silicon (PSi) layers which exhibit a strong in-plane anisotropy of the refractive index (birefringence). Single- and multiple layers of anisotropically nanostructured silicon (Si) have been fabricated and studied by polarization-resolved reflection and transmission measurements. Dielectric stacks of birefringent PSi acting as distributed Bragg reflectors have two distinct reflection bands depending on the polarization of the incident linearly polarized light. This effect is caused by a three-dimensional (in plane and in-depth) variation of the refraction index. The possibility of fine tuning the two orthogonally polarized reflection bands and their spectral splitting is demonstrated.

We report on a system exhibiting extremely efficient light scattering properties: a liquid network formed by capillary condensation in a porous matrix. We find that the scattering efficiency depends strongly on the filling factor of the liquid in the pores, its dielectric constant, and the type of termination of the internal surface of the layer. The spectral dependence of the scattering efficiency of photons evidences that the phenomenon is governed by a Mie-type scattering mechanism. The mean free path of photons in this system is found to be in the micrometer range.

Electrical properties of two kinds of sandwich structures (SnO2:F/por-TiO2/Ti and Si/por-TiO2/Pd) are investigated by the methods of I–V, C–V characteristics and DLTS in vapors of water and alcohol. It has been demonstrated that besides the change of the conductivity and of the capacitance of the por-TiO2 layers one can also use for gas sensing the change of the high frequency capacitance of the MOS type structure, measurement of the current response at relatively low frequencies and the modification of the charge transfer between the Si bulk and states near the por-TiO2/Si interface.

The photoassisted electrical transport is investigated in porous TiO2 (anatase) layers by impedance spectroscopy (IS) and time-of-flight (TOF) at different temperatures and pressures of oxygen. The experiments were carried out under the conditions of zero bias potential (no electron injection at the contacts takes place) and of relatively high bias potential when electrons are injected from the contact into the porous TiO2 layer. Illumination with photons having energies below the band gap leads to a strong increase of the conductivity while the conductivity is practically unchanged for illumination with ultra violet light independent of the applied bias potential. Besides the light induced excess carrier generation, TOF measurements show an increase of the drift mobility under illumination with blue light. The results were explained by the lowering of the barriers between sintered TiO2 nanocrystals due to separation of photoexcited charge carriers.

Age-related macular degeneration (AMD) is the leading cause of visual impairment and blindness in the elderly. Successful therapy is not yet available for the majority of patients, especially not for patients with dry AMD. AMD at cellular and molecular levels is at least in part a microcirculatory disorder of the retina. Rheopheresis is a safe and effective modality of therapeutic apheresis to treat microcirculatory disorders and represents a novel treatment option for patients with dry AMD. Elimination of a defined spectrum of high molecular weight proteins from human plasma including pathophysiologically relevant risk factors for AMD such as fibrinogen, cholesterol, von Willebrand factor, and α2-macroglobulin results in the reduction of blood and plasma viscosity as well as erythrocyte and thrombocyte aggregation. Pulses of lowering blood and plasma viscosity performed as a series of Rheopheresis treatments lead to rapid changes of blood flow, subsequently inducing sustained improvement of microcirculation and recovery of retinal function. Two controlled randomized clinical trials demonstrated the safety and efficacy of Rheopheresis for the treatment of AMD patients, especially for those with the dry form. Recently the interim analysis of the sham-controlled, double blind, randomized multicenter Multicenter Investigation of Rheopheresis for AMD (MIRA-I) trial confirmed these results. The framework of completed and still ongoing controlled clinical trials in combination with postcertification studies including the RheoNet registry represents a comprehensive quality management approach for this novel interdisciplinary therapy for AMD. The development and continuous update of guidelines for the precise indication of Rheopheresis for AMD follows the requirements of evidence-based medicine.

Purpose In diabetes hyperglycemia and other mechanisms lead to the production of oxidative metabolites that can enhance the production of growth factors, leading to increased proliferative activity. Strict blood-glucose control reduces the progression of retinopathy better than standard control. This study investigated patients with diabetic retinopathy for evidence of oxidative metabolites in plasma and the vitreous body, correlating these values with blood-glucose control.Methods The study comprised 136 patients suffering from proliferative diabetic retinopathy. They were grouped according to their mean glycosylated hemoglobin value for the last 9–12 months. Patients with values = 10% (mean 8.7%; n=64) were considered strict glucose control patients, those with values > 10% (mean 12.8%; n=72) were considered standard glucose control patients. Lipid peroxides were determined in blood plasma and the vitreous body by two methods (thiobarbituric acid reactive substances and malondialdehyde-like substances). If present, retinal traction with fibrovascular proliferations (>2 disk areas) was quantified and served as an indicator of proliferative activity.Results Patients with strict blood-glucose control had significantly (p < 0.01) lower lipid peroxide values in plasma and the vitreous body than standard glucose control patients. These latter had significantly (p<0.01) higher rate of fibrovascular proliferation (50%) than strict glucose control patients (9.7%).DISCUSSION Strict blood-glucose control leads to reduced oxidative tissue damage both systemically and locally in the eye, and reduced proliferative activity. Oxidative metabolites can stimulate proliferation by increasing the amounts of different growth factors an cytokines such as vascular endothelial growth factor. Thus, it can be speculated that in hyperglycemia the relative increase of oxidative metabolites contributes both to damage of retinal vessels and to more pronounced proliferative activity in diabetic retinopathy.

The morphology of porous silicon layers has been investigated by polarization resolved photoluminescence measurements in different geometrical arrangements. A uniaxial alignment of the long ellipsoidal axis of the aspheric Si nanocrystallites (NCs) parallel to the [100] growth direction is found. This overall orientation of the NCs is randomized with decreasing size of the NCs.

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We deduce the values of the absorption cross-section of silicon nanocrystals and the spectral behaviour of the joint density of their electronic states in a wide range of energies. The very large variation of their values versus energy of the absorbed light is attributed to the enhanced optical transition oscillator strength but reduced density of electronic states towards higher confinement energies.

Polarization dependent photoluminescence (PL), time-resolved PL and PL excitation experiments are performed in order to clarify the origin of the linear polarization of the PL of porous silicon excited by linearly polarized light. It is shown that this effect, when PL is excited significantly above the detection energy, is not related to a coherent exciton alignment or selective optical excitation of those nanocrystals whose transition dipole moments are oriented parallel to the polarization vector of the exciting light. The experimental results are interpreted in the framework of a dielectric model assuming aspheric nanocrystals

Microwave conductivity and Raman spectroscopy were applied to study the influence of light and thermal annealing on porous TiO2 properties. Microwave absorption in porous TiO2 (anatase) showed an anomalous behaviour in the presence of light excitation (at 514 nm, i.e. below, or 356 nm, i.e. above the band gap). Exposure to light at a time scale of minutes reduces the microwave conductivity, in contrast to many bulk semiconductors excited above band gap. A reduced content of oxygen after heating in vacuum leads also to a reduction of microwave absorption. Both observations are in apparent contradiction with dc conductivity in TiO2. By comparison with light-induced EPR experiments, we conclude that the oxygen removal creates deep defects to which are transferred electrons previously trapped in shallow donors. As a consequence, this decreases the polarisability of TiO2 nanoparticles, the microwave absorption, and the dielectric constant.

A strong dependence of the electrical conductivity of mesoporous Si (meso-PS) on the dielectric constant of ambient surrounding Si nanocrystallites has been shown by current–voltage and photovoltage measurements. A sharp increase of free carrier concentration in a meso-PS layer filled by polar liquids with high dielectric constants has been found. The observed phenomenon is explained by activation of impurities (boron atoms) due to the decrease of binding energy of carriers trapped by the impurity potential.

no Abstract

Summary. Let K and $ \overline K $ be fields containing $ {\Bbb Q} $. We characterize pairs of additive functions $ f,g: K \to \overline K $ satisfying a functional equation¶¶$ g(x^{ln}) = f(x^l)^n \quad \text{respectively} \qquad g(x^{ln}) = Ax^{ln} + x^{ln-l}f(x^l) $,¶where $ n \in {\Bbb Z} \setminus \{0,1\} $, $ l\in {\Bbb N} $ and $ A \in K $.

(111) lead zirconate titanate PZT films of various thicknesses 700, 500 and 300 nm on Pt electrodes have been investigated by tapping mode atomic force microscopy (TMAFM). The PZT crystallites were found to partition into slabs of 90° domains in all cases with domain walls oriented along 〈110〉 planes. The polarization c-axis of the domains was inclined by 35° towards the surface and tilted to the surface normal alternately by +45° or —45° for a fully poled film. The grain size was found to be 200 nm, however, the domain width w scaled with the square root of the film thickness h (w = 19 nm for h = 700 nm, w = 16 nm for h = 500 nm, w = 12 nm for h = 300 nm). Furthermore, (111) PZT films (all 700 nm thickness) have been investigated on three different substrates: For (111) PZT on (111) Pt, an average domain width of 19 nm was measured (700 nm). A mean domain width of 20 nm was detected for (111) PZT on polycrystalline IrO2 and 22 nm for (111) PZT on amorphous Al2O3 (700 nm thickness). The calculated domain width is 16 nm for a film of 500 nm thickness according to the Speck-Romanov-Pompe-Streiffer theory of elastic relaxation in ferroelectric films.

We review some of our recent works on the porous Si luminescence and emphasize the importance of the nonradiative Auger-process in the description of the Si nanocrystal photoluminescence (PL) properties. Due to a very long radiative time already at moderate levels of optical excitation a double occupation of crystallites by e-h pairs is achieved. This results in an efficient photoluminescence suppresion by a resonant pump beam and persistent hole burning phenomena. The hole burnt in the luminescence spectrum in a pump-to-probe or persistent mode has two well defined onsets related to the TO momentum conserving phonons of Si. An increase of the temperature heals the spectral hole and this is accompanied by a thermoluminescence signal. These results allow us to conclude that most of the luminescence of porous Si arises from radiative recombination between states confined inside the nanocrystals.

Thin Al2O3coatings can provide oxidation protection on metallic high temperature components. For this purpose Ni-base alloys for gas turbine applications are plasma spray coated with MeCrAlY alloy. At high temperatures this alloy forms a native Al2O3scale for oxidation protection. In order to increase the efficiency of this oxidation protection a thin artificial Al2O3layer can be deposited on the metal surface. Such a coating has to be dense with a very low void fraction and with good adhesion to the substrate.

Methane or acetylene added to an argon or helium arc plasma is dissociated and/or ionized effectively in order to deposit amorphous carbon (a-C:H) layers. The plasma can be confined or spread out by a homogeneous or cusp magnetic field. The issue of the present study is whether the magnetic confinement has an influence on the type of ions governing the deposition and their energy. To this end, an energy-resolved mass spectrometer (plasma monitor) was used, screened off by a μ-metal cage. It appears that, for strong magnetic fields of up to 10 mT, besides CH3+and C2H2+ions (from the methane and acetylene admixture, respectively), also relatively more dissociated species like CHx+(x=2, 1, 0) and CyHz(y=2, 1, 0; z=1, 0) arise. Especially with the C2H2admixture, atomic C+ions appear to become more abundant with increasing magnetic field. The energy of the ions appears to decrease with increasing magnetic field. With Langmuir cylindrical electric-probe measurements it was confirmed that this is related to a decreasing plasma potential. By means of a numerical model, spatially resolved density profiles of the most important species were calculated. Depending on the reactor parameters, relevant ion densities are of the order of 109–1010cm−3, resulting in deposition rates of up to some μm h−1.