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The status of bulk superconductor magnetic levitation (Maglev) train technique is evaluated. Existing industrial magnetic trains (electromagnetic, electrodynamic) point to key performance factors as load, speed, efficiency, and environmental protection. On that basis, a feasibility analysis of trapped-field train demonstrators should be attained. HTS bulk trapped field experiments at lower temperatures up to 6.8 T were performed and the HTS mass production capability is indicated. For increasing the transport load, a new generation of robust and mobile LN 2 vacuum cryostat type is developed. The new device is designed and scaled up according to the technique and practical experience of a smaller cryostat with 250 kg load and 30-40 h operation time. A test vehicle levitated by four cryostats on a magnetic guideway is presented. It is capable of levitating more than 1 ton. The new cryostat consists of 30 tiles 3-seed YBCO bulks, it levitates up to 0.5 ton at 10 mm distance, and with 5 l LN 2 stored it achieves an operation time of up to 2 days. We report about the integration of YBCO bulks, thermal insulation, LN 2 refilling, and mechanical construction. With the new development, we obtain evidence to manage higher train forces of several tons.

Maglev train is a transportation system that uses magnetic interaction and brings many technical, economic, and environmental benefits. Here, the progress in designing and manufacturing portable vacuum cryostats containing 24 high-quality threefold seeded Yttrium Barium Copper Oxide (YBCO) bulks with up to 40 h LN2 cooled operation time is reported. Permanent magnet (PM) excitation on a magnetic guideway generates forces on the YBCO cryostats and provide train levitation forces of several tons by assembling the portable cryostats. By means of experiments and systematic improved fabrication, we describe the process of material and device scaling-up to gain industrial-near transformation and application. Current PM guideway design with the magnetic flux of 0.5 T at maximum limits the force density to 5-10 N/cm 2 . The conditions for further development, effective fabrication, and design-oriented progress of higher loads, great robustness, and better thermal insulation respective longer operation time are outlined.

Practical REBCO bulk superconductor-based components and devices as rotational and linear magnetic bearings are well understood. A high-stiffness high temperature superconductor (HTS) magnetic bearing with 0.1 mm low-hysteresis is demonstrated for narrow-gap operation. Linear magnetic bearings up to 10-ton load have been successfully implemented in linear Maglev trains under real outside conditions. The REBCO bulk-based magnetic levitated (Maglev) trains are proposed for urban and low-speed transport concepts. On the contrary, high-mobile, lightweight, and flexible HTS bulk components are developed under the extreme and safe conditions of manned spaceflight for astronomy and space application. YBCO bulk proton irradiation tests for space application are presented. In the International Space Station (ISS), the interaction of the earth magnetic field with a perfect fast-moving diamagnet within a project called Magvector/MFX is measured and investigated. We compare an anticipated model with space experiments performed in the last two years in the ISS. The paper will summarize recent progress in this field, and present how cryogenic and HTS component design can positively impact levitation and screening performance. Properties of cryogenic systems and devices of mobile applications in their complexity and required robustness will be compared to stationary HTS systems, and the effect of different cooling options has to been considered.

Copper plating technology is the efficient method for the nonvacuum metal deposition both on RABITS Ag/REBCO/Ni5%W and IBAD Ag/REBCO/YSZ/. Common to all fabrication steps is the need for increasing the production yield. Because of the Faraday law, the effective plated copper mass of 20-μm Cu layer, the plating speed is limited. Here, we report about a constructed high-rate fabrication plating unit for tapes from 4 to 12 mm width operating with a new powerful pulse plating electronics, optimum designed 12 × 10-cm-long reel-to-reel multichamber plating cells, and improved electrolytes. We have been using a new CuSO 4 electrolyte with H 2 SO 4 and additives to gain the current density to 80-200 mA/cm 2 . The maximum Cu deposition of 2 × 20 μm surround layer gives an output of about 8 m/hour. Possible corrosion and degradation effects due to overvoltage >3 V are investigated. A new concept of a multilane plating machine is proposed to deliver a plating speed of 100 m/h. The results have shown a robust reel plating process of copper deposition on coated conductors aiming at an economic step of conductor production.

Um das korrekte Zusammenspiel einzelner Elemente von komplexen Prozessketten vor ihrem realen Aufbau zu überprüfen, können diese in der virtuellen Welt erstellt werden. Durch die Visualisierung und Simulation des Prozesses ist die vorausgehende Planung kontrollier- und optimierbar. Zusätzlich kann die VR (Virtual Reality)-Darstellung für den (Re-)Designprozess sowie als Kommunikationsgrundlage zwischen verschiedenen Unternehmensbereichen als wichtige Hilfestellung dienen. To validate the correct interaction between the separate elements of complex process chains before the real build-up, they can be created in the virtual world. By visualizing and simulating the processes, the preceding planning work can be checked and optimized. Additionally, the VR presentation can be used for the (re)desgin process and serve as a communication base for different functional areas, providing important assistance.

Einleitung: Die hospizliche und palliative Versorgung von Migranten am Lebensende in Deutschland wurde bislang kaum untersucht; eine Unterversorgung wird angenommen. Die vorliegende Arbeit wendet sich dem Thema aus der Sicht von Hospizhelfern eines interkulturellen Hospizdienstes zu und beleuchtet die Situation ostasiatischer Migranten am Lebensende. Methodik: 16 strukturierte Interviews mit Hospizhelfern wurden durchgefuhrt und nach der Qualitativen Inhaltsanalyse ausgewertet. Alle Hospizhelfer hatten selbst einen Migrationshintergrund und konnten auf Erfahrungen von 92 Begleitungen ostasiatischer Patienten zuruckgreifen. Ergebnisse: Es konnten 5 Hauptkategorien herausgearbeitet werden: Heimat, Medizinische Versorgung, Soziales Netzwerk und Familie, Religion und Spiritualitat sowie Kommunikation. Unterkategorien liefern dabei genauere Beschreibungen. Insbesondere Essen, Einsamkeit und Schmerzen waren bestimmende und kategorienubergreifende Themen. Diskussion: Neben bekannten Problemfeldern von Palliative Care bei Migranten wie fehlende Dolmetscher und erschwerter Zugang zur Versorgung, zeigen die Ergebnisse konkrete Beispiele zur Verbesserung auf. Eine flexiblere Essensversorgung, Forderung von Netzwerken der kommunalen Kulturgemeinden sowie differenzierte Schmerzanamnesen sind u. a. Moglichkeiten einer kultursensiblen Begleitung ostasiatischer Patienten.

Metallic copper is the obvious engineering stabilizing partner for the second-generation coated conductor (CC) wire. The copper shunt on the conductor gives a number of electric, thermal, and mechanical advantages. Nonvacuum deposition of copper by electrochemical plating is now an established CC technology, both single sided as well as surrounded. Cu plating on RABITS Ag/YBCO/Ni5%W and IBAD Ag/YBCO/YSZ/Hastelloy conductors are reported in the applied cell potentials, currents, and Coulombs. The diffusion-limited plating current in copper sulfate and alkaline electrolyte is investigated in view of the largest rate of mass transfer. The electrochemical deposition opens a further window of design and conductor engineering. Beneficial Cu plating with Ag cap layer is performed, and J c is evaluated. All parameters are transferred into the reel technique to improve the efficiency of copper plating. This paper describes the optimum and merits of Cu shunt parameters in geometry, thickness, and wire robustness.

Experimental studies and theoretical modeling of high temperature superconductor (HTS) magnetic bulk applications are conducted and reported. The magnetic force density as a function of the magnet superconductor separation in the mirror image FEM 2D picture shows a strong dependency on the distance and PM mass. The behavior contrasts all attempts of generating high magnetic levitation forces with a minimum of material effort. An optimum configuration PM HTS coupler has been designed and built for a 300 mm wafer spin test apparatus. With rotational speeds up to 1500 rpm a safe operation and handling the imbalance of the wafer spin clutch by passing the resonance speed at 370 rpm is investigated. The smart rotor rotation is studied to drive a half-wave plate of a polarization apparatus to detect cosmic microwave radiation safely through resonances and imbalance effects.

The epidemic-like rise in chronic low back pain in western industrial nations is less an expression of a medical than a psychosocial phenomenon. Differentiation between acute, chronic or chronifying pain is of crucial importance for therapeutic procedures. Pain syndromes in the muscular-skeletal system tend to become chronic to a far larger extent than expected. More than 80 % of low back pain represents a functional pain syndrome and does not show any pathoanatomical correlate. Pain existing independently seems to be predestined by a somatic and psychosocial deconditioning syndrome. Those at risk of chronifying pain or those whose pain is already chronic should be given an interdisciplinary, multimodal therapeutic program. A pilot study was carried out in our clinic: multidisciplinary treatment was given to our patients (of which over 90 % belonged to stages II and III on the Gerbershagen scale) and the result was significant improvement in the measurements of pain intensity, sensoric and affective pain perception, their list of complaints, the common scale of depression and the pain disability index. Taking previously published studies into consideration, it is safe to say that a multidisciplinary, multimodal program of therapy even after stay in hospital results in considerable relief of pain and improvement in the ability to cope with the pain for patients with chronified pain syndromes in the muscular-skeletal system which are resistant to treatment on an outpatient basis.

In human atrial myocytes the transient outward current Ito develops a conspicuous faster inactivation with increasing temperatures. Since β-subunits are known to modulate Ito current kinetics, we hypothesized that the temperature sensitivity of Ito is not only determined by the property of the ion-passing α-subunit Kv4.3 but also by its interaction with accessory β-subunits. We therefore studied the influence of the transmembrane β-subunits KCNE1, KCNE2 and DPP6 on Kv4.3/KChIP2 channels in CHO cells at room temperature and at physiological temperature. Exposure to 37 °C caused a significant acceleration of the channel kinetics, whereas current densities and voltage dependences remained unaltered at 37 °C compared to 23 °C. However, Kv4.3/KChIP2 channels without transmembrane β-subunits showed the strongest temperature sensitivity with considerably increased rates of activation and inactivation at 37 °C. KCNE2 significantly slowed the current kinetics at 37 °C compared to Kv4.3/KChIP2 channels, whereas KCNE1 did not influence the channel properties at both temperatures. Interestingly, the accelerating effects of DPP6 on current kinetics described at 23 °C were diminished at physiological temperature, thus at 37 °C current kinetics became remarkably similar for channel complexes Kv4.3/KChIP2 with and without DPP6 isoforms. A Markov state model was developed on the basis of experimental measurements to simulate the influence of β-subunits on Kv4.3 channel complex at both temperatures. In conclusion, the remarkably fast kinetics of the native Ito at 37 °C could be reproduced by co-expressing Kv4.3, KChIP2, KCNE2 and DPP6 in CHO cells, whereas the high temperature sensitivity of human Ito could be not mimicked.

ATZ Company has constructed about 130 HTS magnet systems using high-Tc bulk magnets. A key feature in scaling-up is the fabrication of YBCO melts textured multi-seeded large bulks with three to eight seeds. Except of levitation, magnetization, trapped field and hysteresis, we review system engineering parameters of HTS magnetic linear and rotational bearings like compactness, cryogenics, power density, efficiency and robust construction. We examine mobile compact YBCO bulk magnet platforms cooled with LN 2 and Stirling cryo-cooler for demonstrator use. Compact cryostats for Maglev train operation contain 24 pieces of 3-seed bulks and can levitate 2500–3000 N at 10 mm above a permanent magnet (PM) track. The effective magnetic distance of the thermally insulated bulks is 2 mm only; the stored 2.5 l LN 2 allows more than 24 h operation without refilling. 34 HTS Maglev vacuum cryostats are manufactured tested and operate in Germany, China and Brazil. The magnetic levitation load to weight ratio is more than 15, and by group assembling the HTS cryostats under vehicles up to 5 t total loads levitated above a magnetic track is achieved.

Understanding the behavior of single proteins at the polyelectrolyte multilayer film/solution interface is of prime importance for the designing of bio-functionalized surface coatings. In the present paper, we study the adsorption of the model proteins, albumin and lysozyme, as well as basic fibroblast growth factor (FGF-2) on a polysaccharide multilayer film composed of quaternized chitosan and heparin. Several analytical methods were used to describe the formation of the polysaccharide film and its interactions with the proteins. Both albumin and lysozyme adsorbed on quaternized chitosan/heparin films, however this process strongly depended on the terminating polysaccharide. Protein adsorption was driven mainly by electrostatic interactions between protein and the terminal layer of the film. The effective binding of FGF-2 by the heparin-terminated film suggested that other interactions could also contribute to the adsorption process. We believe that this FGF-2-presenting polysaccharide film may serve as a biofunctional surface coating for biologically-related applications.

We present here a report about a copper stabilizer processing unit and the function on IBAD – HPLD coated conductor properties. A continuous reel - to- reel Cu plating stabilizer manufacturing technology was developed and will be transferred to Bruker HTS. The quality and performance of one- side and double- side 20 μm Cu layers are evaluated with respect to critical current behavior and conductor joint fabrication. By current pulse plating technology in copper sulphate CuSO4 we have gained to optimize the plating speed to more than 30 m/h by variation the electrical, electrode and solution parameters. With the new 6 m long Cu reel plating unit improved production yield and reproducible Cu stabilizer performance is demonstrated. The non-vacuum deposition unit has a high flexibility in processing a homogeneous Cu stabilizer of thickness of 5 – 50 μm. Using the Cu layer face -to -face joints with resistances of 10 -7 Ωcm 2 level by standard soldering are becoming routine. We will provide an overall analysis of our construction and results in the PLD Cu – HTS hybrid conductor engineering and processing.

We investigate and review concepts of multi – seeded REBCO bulk superconductors in mobile application. ATZ's compact HTS bulk magnets can trap routinely 1 T@77 K. Except of magnetization, flux creep and hysteresis, industrial – like properties as compactness, power density, and robustness are of major device interest if mobility and light-weight construction is in focus. For mobile application in levitated trains or demonstrator magnets we examine the performance of on-board cryogenics either by LN2 or cryo-cooler application. The mechanical, electric and thermodynamical requirements of compact vacuum cryostats for Maglev train operation were studied systematically. More than 30 units are manufactured and tested. The attractive load to weight ratio is more than 10 and favours group module device constructions up to 5 t load on permanent magnet (PM) track. A transportable and compact YBCO bulk magnet cooled with in-situ 4 Watt Stirling cryo-cooler for 50 – 80 K operation is investigated. Low cooling power and effective HTS cold mass drives the system construction to a minimum – thermal loss and light-weight design.

By applying high-rate copper electroplating technique the reliable fabrication of a copper stabilizer on coated conductor with an 1 μm Ag cap is investigated. The obtained mechanical, electrical and encapsulation properties due to a 20 μm thick Cu stabilizer on the surface improve the practical and technical performance. A copper sulphate CuSO4 based pulse plating technique is capable to deposit a 20 micrometer thick copper layer in a fast and continuous non-vacuum process. A surround Cu layer protects the HTS conductor surface against salt aqueous solutions, humidity, and against cryogenic liquids LN2 and liquid helium. With the copper stabilizer conductor solder joining with a contact resistance of 200 nΩcm2 becomes possible. Further effort is being made to develop and construct a high-rate and high throughput continuous reel-to-reel modular plating unit for deposition of long length ( >; 400 m). The paper describes the practical achievements within the conductor fabrication.

High Temperature Superconducting (HTS) interaction shows a great potential in rotational bearing and linear Maglev technology. Besides the superconductor each application sets additional specific technical requirements. The challenges of use the various constructions and applications in the combination of the cold HTS material and the required technical periphery are discussed. ATZ's 0.5-ton HTS production per annum has enabled increased performance in a number of magnetic applications. Engineering properties, advanced magnetic excitation systems and thermal and mechanical stability of robust high-load YBCO bearings have been demonstrated. Effort is being made in the development of mobile HTS Maglev devices. We have designed and produced advanced 40-cm-long bulk cryostats, having 2-mm magnetic distance to the outside and operating more than one day without refilling. 24 vacuum cryostats have been manufactured for a magnetic train construction capable to transport up to 60-kN total vehicle and passenger weight and dedicated to operate on a 200-m-long track.

Adelwitz Technologiezentrum (ATZ) and L-3 Communications Magnet Motor (L-3 MM) are currently mounting a compact-designed flywheel energy storage system (FESS) with total magnetic bearing support. Final assembly and test operation were performed during 2008-2009. After calculations and experiments, we decided to improve rotor stabilization by stiffer geometry. In addition, two dynamical emergency bearings contribute to robust and safe flywheel operation in critical revolution-per-minute situations. A planned energy capacity of 5 kWh is now obtained at about 8000 r/min, whereas an increased capacity of 10 kWh will be stored at a speed of 10 000 r/min. The total weight of the flywheel unit is about 1200 kg plus power electronics and cooling system. The heavier 600-kg rotor causes new design and construction work in mechanical elements, magnetic support bearings, cooling, and power electronics. Due to the here reported construction changes and increased rotor speed, scaling to even larger energy storage performance of 15-20 kWh seems achievable. ATZ and L-3 MM obtained a corresponding order to develop and deliver a 15-kWh/400-kW high-temperature-superconducting FESS for a Korean local grid UPS application.

ATZ Company has successfully developed high temperature superconducting (HTS) magnetic bearings for power energy application and high-speed machinery. Journal-type design and improved HTS magnetic properties increasingly fulfill industrial prototype requirements. Maximum load up to 1.1 ton, stiffnesses in 3-4 kN/mm level, simultaneous self-stabilization in axial and radial directions, largegap operation of 5-6 mm and reliable machine cooling in the 50-60 K region characterize the present progress of HTS magnetic bearings. A 200 mm HTS bearing of 10 kN load capacity is fabricated and integrated in a 5 kWh/250 kW flywheel energy storage system. We report about a new large-gap HTS magnetic coupling system ensuring 300 mm wafer treatment inside a closed processing chamber in semiconductor industry. A linear MAGLEV transport system consisting of four modular cryostat units have been recently fabricated in a prototyping process. The four HTS cryostats can carry almost 1 ton at 10 mm magnetic gap above a magnetic guideway with a force density of about 5 N/cm2. Due to perfect thermal insulation each cryostat operates more than 24 hours without refilling LN2.

BACKGROUND AND OBJECTIVE: Advances in understanding the pathophysiology and treatment of stroke have led to changed requirements, including the prehospital phase, for the care of patients with acute stroke. Rapid transport to a regional stroke centre is nowadays considered to be the standard for optimal quality of care. A retrospective cross-sectional analysis was undertaken in 1996 in the region of the town of Munster to test the quality of medical care provided by physicians on emergency call. PATIENTS AND METHODS: 250 of 3001 protocols (8.3%) filled in by emergency call physicians were selected in which the initial diagnosis of transitory ischaemic attack, stroke or cerebral haemorrhage had been made. Quality of patient care was assessed according to the following criteria; (1) complete medical treatment (blood sugar, blood pressure, cardiac rhythm and arterial oxygen saturation, including relevant treatment of any abnormality) (2) action time (arrival of emergency doctor within 12 min and arrival at hospital within 50 min); (3) type of the admission hospital (stroke centre defined as a hospital experienced in the treatment of stroke, with neurological and medical departments, as well as 24-hour cover for computed cranial tomography). A summated indicator of "optimal care" was used to determine whether the three stated criteria were met. RESULTS: Mean age of the stroke patients was 72.3 years. While the above mentioned quality criteria for the action time were met in 93.5% of patients, only 56.0% were admitted to a stroke centre, and this was significantly more often the final destination for patients under the age of 65 years than for older ones (p = 0.049). The quality indicator "complete medical treatment" was met for 27.2% of the transported patients. Measured according to present-day criteria, only 18.6% of patients received such optimal treatment. CONCLUSION: This analysis indicates that modern prehospital treatment of stroke patients does not reach adequate standards. In particular, it is not comprehensive. While the "action time" is usually adequate, there are deficiencies regarding the quality of medical care and the choice of the admission hospital. Further education for emergency physicians with respect to the management of stroke syndrome should be an integral part of any regional quality programme. The number of hospitals with adequate competence in the acute management of stroke cases is still insufficient.

Using the patch-clamp method, we studied the influence of external alkali and organic monovalent cations on the single-channel properties of the adenosine triphosphate (ATP)-activated recombinant human P2X(7) receptor. The slope conductance of the hP2X(7) channel decreased and the reversal potential was shifted to more negative values as the ionic diameter of the organic test cations increased. From the relationship between single-channel conductance and the dimensions of the inward current carrier, the narrowest portion of the pore was estimated to have a mean diameter of approximately 8.5 A. Single-channel kinetics and permeation properties remained unchanged during receptor activation by up to 1 mM ATP(4-) for >1 min, arguing against a molecular correlate of pore dilation at the single P2X(7) channel level. Substitution of extracellular Na(+) by any other alkali or organic cation drastically increased the open probability of the channels by prolonging the mean open time. This effect seems to be mediated allosterically through an extracellular voltage-dependent Na(+) binding site with a K(d) of approximately 5 mM Na(+) at a membrane potential of -120 mV. The modulation of the ATP-induced hP2X(7) receptor gating by extracellular Na(+) could be well described by altering the rate constant from the open to the neighboring closed state in a C-C-C-O kinetic receptor model. We suggest that P2X(7) receptor-induced depolarization and associated K(+)-efflux may reduce Na(+) occupancy of the regulatory Na(+) binding site and thus increase the efficacy of ATP(4-) in a feed-forward manner in P2X(7) receptor-expressing cells.

Flywheel energy storage systems (FESS) are expected to contribute to uninterruptible power supplies (UPS) and power quality tasks significantly. We present design and the component results of a compact 5 kWh/250 kW HTS flywheel whereby the rotor will be totally magnetically stabilized. The design is optimized for highly integrated functionality of rotor body, generator/motor and bearings. The heart of the FESS is an ironless high power PM generator/motor delivering 250 kW. An advanced flywheel body manufactured from graphite fiber is stabilized by two magnetic bearings. A prototype 200 mm HTS bearing has been constructed and tested up to a load of 1 ton axially and 0.47 ton radially capable to carry the rotor weight of about 0.5 t. With a coefficient of friction (COF) of about 10-6 the rotational drag was low. A passive PM bearing giving 80 N/mm radial stiffness/per pole was studied. HTS-PM damping response dependent on the temperature shows Lehr factors of 5-10% damping between 50 and 80 K. Eddy current dampers could support rotor dynamic stability.

The considerable development effort of HTS magnetic bearings with respect to heavy loads is demonstrated. Radial type 200 mm bearing in an optimized design was developed for implementation in a new 5 kWh superconducting flywheel energy storage system. A prototype bearing, consisting of a modular assembled melt textured YBCO bulk 200 mm hollow cylinder with permanent magnet rotor is presented. Axial rotor displacement causes pinning forces of 8 and 10 kN axially at a temperature of 78 K and 71 K, respectively. Maximum radial forces are 4.7 kN at sub- cooled LN2. Fabrication technology incorporates the construction and engineering of a low-weight, nonmagnetic G-10 bearing cryostat. Ultra-low heat transfer structural elements were designed and constructed to reduce the thermal loss through the support to less than 2 Watt under 1 ton load.

Human P2X7 receptors were expressed in Xenopus laevis oocytes and single channels were recorded using the patch-clamp technique in the outside-out configuration. ATP4- evoked two types of P2X7 receptor-mediated single channel currents characterized by short-lived and long-lived openings. The short- and long-lasting open states had mean open times of approximately 5 and approximately 20 ms and slope conductances near -60 mV of 9 and 13 pS, respectively. The open probabilities of the short and long openings were strongly [ATP4-]-dependent with EC50 values of approximately 0.3 mM and approximately 0.1 mM ATP4-, respectively. The channel kinetics did not change significantly during sustained P2X7 receptor activation for several minutes, as was also observed in recordings in the cell-attached patch-clamp configuration. Activation and deactivation of the short openings followed exponential time courses with time constants in the range of 20 ms, and displayed a shallow [ATP4-] dependence of the activation process. The kinetics of the short channel openings at negative membrane potentials fitted well to a linear C-C-C-O model with two ATP4- binding steps at equal binding sites with a dissociation constant Kd of 139 microM.

A 200 mm cylindrical engineering prototype high temperature superconducting (HTS) was designed and fabricated. Measurements show that the 17 kg PM rotor can suspend safely 1000 kg in axial direction and 470 kg radially. The rationale for the bearing performance is to stabilize a 400 kg rotor of a new compact 5 kWh/280 kW flywheel energy storage system (COM - FESS). Measurements of the magnetic bearing force, stiffness and drag-torque are presented indicated the successful targeting a milestone in the HTS bearing technology. The influence of the PM configuration and the YBCO temperature on the bearing performance was experimentally studied, providing high-force or high-stiffness behaviour. The axial stiffness 5 kN/mm at 0.5 mm displacement is the highest value of a HTS bearing we know.

Thermal encapsulation of HTS is one way to fabricate high-efficient HTS magnetic bearings for flywheels, motors and generators. We have been designed, manufactured and tested 200 mm axial and radial bearings for loads close to 300 kg. The maximum load to bearing weight is in the 10 to 1 ratio. At 77 K, a vacuum cryostat around the HTS reduces basic thermal losses to 6.4 W with very small rotational ac losses of 0.1 W/1000 rpm. The encapsulation reduces the cryogenic threshold in the application and allows a convenient adaptation of cryo-coolers. Basic elements are the melt textured YBCO single crystals, appropriately machined and glued in a copper ring in the center of the vacuum cryostat combined with an intrinsic cryo-sorption pump. Ten axially stacked 200 mm PM rings comprise the magnetic excitation system of the rotor. The coefficient of friction is about 10/sup -4/ at ambient and 10 times lower at reduced pressure. For higher loads the manufacturing effort of HTS bearings, becomes comparable with mechanical bearings, increasing the chances of replacing mechanical bearings.

Understanding global climate change and developing strategies for sustainable use of our environmental resources are major scientific and political challenges. In response to an announcement of the German Aerospace Center (DLR) for a national Earth observation (EO) mission, the Friedrich-Schiller University Jena and the JenaOptronik GmbH proposed the EO mission Carbon-3D. The data products of this mission will for the first time accurately estimate aboveground biomass globally, one of the most important parameters of the carbon cycle. Simultaneous acquisition of multiangle optical with Light Detection and Ranging (LIDAR) observations is unprecedented. The optical imager extrapolates the laser-retrieved height profiles to biophysical vegetation maps. This innovative mission will reduce uncertainties about net effects of deforestation and forest regrowth on atmospheric CO2 concentrations and will also provide key biophysical information for biosphere models.

The progress of heavy-load HTS bearings depends on improvements in design, material quality and reliable cooling. We have constructed, manufactured and tested a 200 mm HTS journal bearing with a thermally encapsulated YBCO ring. For maximum force the larger gap due to the bearing cryostat (>4 mm) requires adjustment of the magnetic excitation pole distance and the Fe collector shim thickness. HTS material progress is obtained by top-seeded single- or multiple-grain growth which increases the averaged trapped magnetic flux density. Successful YBCO ring growth with radial c axis distribution by seeding the inner ring surface has been performed. The encapsulation ensures a substantially reduced cryogenic effort and stabilizes bearing operation at 78–79 K.

Axial and radial high temperature superconducting (HTS) magnetic bearings are evaluated by their parameters. Journal bearings possess advantages over thrust bearings. High magnetic gradients in a multi-pole permanent magnet (PM) configuration, the surrounding melt textured YBCO stator and adequate designs are the key features for increasing the overall bearing stiffness. The gap distance between rotor and stator determines the specific forces and has a strong impact on the PM rotor design. We report on the designing, building and measuring of a 200 mm prototype 100 kg HTS bearing with an encapsulated and thermally insulated melt textured YBCO ring stator. The encapsulation requires a magnetically large-gap (4–5 mm) operation but reduces the cryogenic effort substantially. The bearing requires 3 l of LN2 for cooling down, and about 0.2 l LN2 h−1 under operation. This is a dramatic improvement of the efficiency and in the practical usage of HTS magnetic bearings.

We have tested a heavy load HTS radial bearing dedicated for use in motors, generators, and flywheels. The HTS bearing is of radial type design providing both radial and axial support. The stator and rotor are modular assemblies which allows up-scaling in size. The superconducting stator is made of polycrystalline melt-textured (pmt) YBCO 200 mm inner diameter hollow cylinder grown in cylinder-like a-b texture. The stator assembly is composed of axially stacked YBCO rings in a Cu tube and cooled from the outside by LN/sub 2/. The rotor consists of stacked annular PM rings in compression on a shaft. This results in a high radial magnetic field gradient. Three such YBCO stators have been fabricated, assembled, and tested for use with a 380 kW superconducting motor developed by SIEMENS. Maximum radial forces of more than 3.7 kN were measured (at a temperature of 68 K) with the shaft at center radial position. The goal is to demonstrate safe operation of heavy rotors in a desired frequency range by providing sufficient forces, stiffness, and damping at critical modes.

Toward demonstrating the potential of resistive HTS fault current limiting behavior bulk polycrystalline melt textured (pmt) YBCO devices in meander-like shape were developed and tested by using 50 Hz AC pulses at 77 K. Meander fabrication is based on high-dense and temperature gradient growth textured YBCO plates, which were mechanically stabilized, diamond tooling CAD cut and prepared with low resistive Cu contacts in lengths between 1-5 m. The nonideal I-V characteristics at normal operation due to the residual grain boundary resistivity was measured to a few tens of microvolts per centimeter at 1000 A. Due to additional metallic shunt layer the conditions for quench protection of inherently inhomogeneous material have been derived, tested and substantially improved. We investigated the feasibility, technical performance and economy of employing robust pmt YBCO to take decisions about the material line of future superconducting fault current limiter (FCL) modules.

Applications of superconductivity in the high-current range, e.g. in fault current limiters or current leads, need advanced contacts between superconducting ceramics and metallic conductors. An electrochemical method for manufacturing a copper metal layer on the ceramics is approved as a fast, economical and reliable method of metallizing the superconducting ceramics. Different approaches of soldering are compared in this study, including a flux-free technology working in an ambient atmosphere. Wetting of the ceramics without premetallisation was enabled by using ultrasonic vibrations. The contacts prepared by the different technologies with or without premetallisation of the ceramics are characterised by electrical measurements in the high-ampere range at liquid nitrogen temperature as well as by investigations of the microstructure by SEM/EDX analysis.

Radial HTS magnetic bearings (SMB) up to 200 mm size are developed and tested in prototype fast rotating machines to demonstrate the potential to replace conventional bearings. The individual rotational bearing components HTS and PM, their physical interaction and technology is reviewed. Characterisation experiments are conducted to understand the rotor dynamic behaviour. In terms of unbalance and critical speeds the suspended wheels and rotors compare favourably with conventional bearing devices. The rationale of our present bearing technology lies in the assembling of both low-speed magnetic bearings for centrifugal and wafer processing units up to 20,000 rpm as well as a high-speed optical mirror accelerated to rim speed of more than 500 m/s (174,000 rpm) confirming stable low-drag and low energy operation. Two new-type U shaped semicircle HTS bearings coupled each with a 6 W/80 K cryocooler of the Stirling type allow the contact–free operation of a Si wafer carrier in semiconductor wet processes.

It is assumed that ATP induces closure of the binding jaw of ligand-gated P2X receptors, which eventually results in the opening of the membrane channel and the flux of cations. Immobilization by cysteine mutagenesis of the binding jaw inhibited ATP-induced current responses, but did not allow discrimination between disturbances of binding, gating, subunit assembly or trafficking to the plasma membrane.A molecular model of the pain-relevant human (h)P2X3 receptor was used to identify amino acid pairs, which were located at the lips of the binding jaw and did not participate in agonist binding but strongly approached each other even in the absence of ATP.A series of cysteine double mutant hP2X3 receptors, expressed in HEK293 cells or Xenopus laevis oocytes, exhibited depressed current responses to α,β-methylene ATP (α,β-meATP) due to the formation of spontaneous inter-subunit disulfide bonds. Reducing these bonds with dithiothreitol reversed the blockade of the α,β-meATP transmembrane current. Amino-reactive fluorescence labelling of the His-tagged hP2X3 receptor and its mutants expressed in HEK293 or X. laevis oocytes demonstrated the formation of inter-subunit cross links in cysteine double mutants and, in addition, confirmed their correct trimeric assembly and cell surface expression.In conclusion, spontaneous tightening of the binding jaw of the hP2X3 receptor by inter-subunit cross-linking of cysteine residues substituted at positions not directly involved in agonist binding inhibited agonist-evoked currents without interfering with binding, subunit assembly or trafficking.

The choice of the material strategies to fabricate bulk high temperature superconductors larger than 10 cm has a significant influence on the performance and reliability of HTS components. The paper considers the various techniques in which magnetic bearings and local current transport devices (current leads and fault current limiters) may be provided: improvement in materials and design. Among bulk growth technique polycrystalline melt textured YBCO rings, rods and plates are a promising concept for the modular up-scaling of current transport and magnetic components if the weak-link behaviour of grain boundaries can be reduced. The fabrication is based on ceramo-crystal growth Bridgman-like directional solidification with an applied spatial and time-dependent thermal gradient on Y 1+ x Ba 2 Cu 3 O 7− δ ( x =0.30–0.60). Novel superconducting magnetic U-shaped bearings are designed, assembled and tested in a magnetically rotating Si wafer carrier. Rotor dynamics is studied in terms of unbalance and critical rpm's. Fabricating and assembling of current lead components and resistive fault current limiter devices with a transport J c of 5–10 kA/cm 2 at 10 μV/cm and at 77 K are discussed, including a galvanic metal surface deposition technology to contact, protect and stabilize the HTS.

Hintergrund und Ziele. Ziel der Studie war es, morphologische Erfolge nach geplant exzentrischer homologer perforierender Keratoplastik (PK) in Abhangigkeit von der Diagnose sowie Transplantatdurchmesser und -lage zu untersuchen. Patienten und Methoden. In unserer retrospektiven Studie wurden 122 exzentrische PK an 96 Augen ausgewertet, die bei 104 Patienten wegen eines Ulcus corneae, 6 mit Narben, 7 mit ektatischen Hornhauterkrankungen und 5 sonstigen durchgefuhrt wurden. Folgende Parameter wurden bei 84 Augen quantifiziert: Transplantatdurchmesser (TDM) und -transparenz, Abstand Hornhautmitte von der zentralen Trepanationskante (ABS) sowie von der Transplantatmitte (Dezentrierung, DEZ). Nach Lage des Transplantates (TPL) in Bezug zur optischen Achse wurden n=17 in “exzentrisch periphere” (EPK) und n=67 in “exzentrisch zentrale” Keratoplastik (EZK) unterteilt. Ergebnisse. Der mittlere Nachbeobachtungszeitraum betrug 25 Monate. Bei EPK war der TDM signifikant kleiner als bei EZK. Die DEZ war bei EPK signifikant groser als bei EZK. Der ABS betrug bei EZK −2,0±1,0 mm, bei EPK +1,3±0,9 mm. Bei EPK/EZK waren 46%/57% kristallklar, 18%/15% leicht trub und 36%/28% vollstandig eingetrubt. Bei Ulkus/Narben/Ektasien/Sonstige waren 45%/75%/100%/75% kristallklar, 18%/25%/0%/0% leicht trub und 37%/0%/0%/25% vollstandig eingetrubt. Mit zunehmendem Grad der Eintrubung nahm die DEZ von 1,4±1,2 mm (kristallklar) uber 1,7±1,3 mm (leicht trub) auf 2,2±1,3 mm (vollstandig trub) zu. Transplantate mit groserem TDM und ABS waren signifikant haufiger klar. Ulzera waren hochsignifikant haufiger trub als Narben/Ektasien. Die Lage des TPL und dessen Klarheit waren nicht signifikant miteinander korreliert. Schlussfolgerungen. Bei exzentrischer perforierender homologer Keratoplastik ist die Grunderkrankung prognostisch bedeutsam fur die Transparenz des Transplantates. Eine zunehmende Exzentrizitat des Transplantates scheint sich nicht zwangslaufig ungunstig auf die Klarheit auszuwirken. Im reizfreien Intervall nach exzentrischer tektonischer Minikeratoplastik kann eine zentrierte perforierende Re-Keratoplastik erwogen werden.

Passive magnetic bearings are of increasing technical interest. We performed experiments with centrifugal rotors to analyze gyroscopic forces in terms imbalance, rotor elasticity and damping. Centrifuge rotors need to be operated soft and stable without whirling the sediments. In order to evaluate optimal parameters critical and resonance behaviors are investigated. Eccentricities up 2 mm are safely passed by accelerating test wheels. In a simple model we describe the effect of passing critical rotational speeds. Measurements of bearing properties and wheel performance are presented. We have constructed a first prototype centrifuge designed with a HTS double bearing which operates a titanium rotor safely up to 30 000 rpm. A 15 W Stirling cooler serves cryogenics of the YBCO stators. From the experiments design guidelines for centrifugal applications with HTS bearings are given.

A progress in the Cu/HTS connection at an industrial-like and economical level has been achieved. We report a successful electrochemical deposition method of medium-scale fabrication of 0.5-50 /spl mu/m thin homogeneous Cu films on HTS surfaces. The microstructure of the layer and the interface properties are characterized by SEM and analytical investigations. We measure contact resistivities of Cu on bulk YBCO in the 0.3 /spl mu//spl Omega/cm/sup 2/ range at 77 K and evaluate it with data from microscopy analysis. The fabrication method allows the Cu deposition on all Cu-O-based HTS materials. Cu prevents HTS long-time degradation and surface corrosion. The metallic layer is capable of improving the electrical and thermal properties of I-ITS components to withstand shock, hot spots and short circuit-currents in electrical systems, e.g. current leads and fault current limiters.

A light scanning device with a rotating mirror up to 3 kHz rotational frequency for directing and aiming a radiation beam at a surface was developed and tested. Conventional fluid and air bearing systems because of friction are unable to accelerate up to 60 mm rotors above 2 kHz frequency. The rationale for the selection of the magnetic bearing configuration using YBCO, the control of the bearing and low power motor concepts are discussed. Radial centering and axial stabilization of the rotor are affected by means of two superconducting radial bearings with oppositely magnetized PM rings. The rim speed of the polygon is close to 600 m/s, giving rise to appreciable centrifugal forces and necessitates high quality material selection. The extreme optical sensitivity requires a soft suspension of the rotor coupled with a high damping efficiency. Low consumption LN/sub 2/ cooling gives stable cryogenic conditions in case of power failure. Features and limitations of this novel scanning system are discussed, especially those related to a higher line deflection frequency.