WorldWideScience
1

MRI in combined subacute degeneration of the spinal cord; MRT bei funikulaerer Myelose  

Energy Technology Data Exchange (ETDEWEB)

The MRI morphology in combined subacute degeneration has only rarely been reported. We describe two patients suffering from subacute combined degeneration of the spinal cord on the basis of a deficiency of vitamin B{sub 12}. In both patients characteristic hyperintense areas on T{sub 2}-weighted images in the posterior columns of the cervical and thoracic cord without contrast enhancement were demonstrated by MRI. (orig.) [Deutsch] Bisher liegen zur wenige Beschreibungen der MR-Morphologie bei funikulaerer Myelose vor. Wir beschreiben zwei Patienten mit den klinischen Zeichen einer funikulaeren Myelose auf der Basis eines Vitamin B{sub 12}-Mangels. Bei beiden konnten mit der MRT charakteristische Signalanhebungen im T{sub 2}-gewichteten Bild in den Hinterstraengen des zervikalen und thorakalen Rueckenmarks gezeigt werden. Eine Kontrastmittelaufnahme war nicht nachweisbar. (orig.)

1999-06-01

2

MRI in preoperative evaluation of chronic paranasal sinusitis - a comparison with CT; MRT in der praeoperativen Diagnostik der chronischen Sinusitis im Vergleich mit der CT  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To determine the value of MRI in the preoperative evaluation of chronic paranasal sinusitis and to compare the results with CT and intraoperative findings. Method/Materials: 42 patients with clinical signs of chronic paranasal sinusitis underwent MRI after CT evaluation on one day, with subsequent functional endoscopic sinus surgery on the next day. Coronary CT was obtained with 5-mm slices and table-feed in the prone position, while MRI was performed in the supine position with coronary T{sub 2}-TSE+pd and coronary and transverse HASTE, each with 5-mm slice thickness. Aquisition time in MRI was less than 8 minutes. Two radiologists reviewed the CT and MRI scans for signs of sinusitis and detection of anatomical landmarks. The results were correlated with the intraoperative findings. Results: MRI offered no artifacts of dental work and showed more often high quality pictures than CT. CT and MRI demonstrated a good correlation in the detection of mucosal pathologies ...

2001-04-01

3

Magnetic resonance imaging (MRI) of the central nervous system in long-term manganese dioxide (MnO{sub 2}) exposed workers; Magnetresonanztomographie des Gehirns bei Beschaeftigten mit chronischer beruflicher Mangandioxid-Exposition  

Energy Technology Data Exchange (ETDEWEB)

Aim: Changes within the brain detected by MRI after chronic manganese poisoning raised the question whether morphological changes of the basal ganglia, particularly of the globus pallidus, could be detected after chronic occupational exposure to manganese dioxide. Results: No cases of parkinsonism were detected in clinical examinations or by other means. The mean manganese concentration in blood was 12 {mu}g/l (range: 3.9-23.3 {mu}g/l). In comparison to the upper reference value of 10 {mu}g/l, 42 workers (56%) had a higher body burden. A significant positive correlation between manganese levels in blood and the PI (indicated by T{sub 1}-shortening) was observed as well as between the CBI and workplace-specific exposure. Brain atrophy was not detected in any of the observed cases. Conclusions: Long-term exposure to manganese dioxide dust correlates with the Pallidum-Index in MRI scans. Although the MRI findings have no current clinical relevance for individuals, further studies are ...

2000-06-01

4

Inflammatory spine disease as a cause of back pain; Entzuendliche Wirbelsaeulenerkrankungen als Ursache fuer Rueckenschmerzen  

Energy Technology Data Exchange (ETDEWEB)

The aim of this review is to evaluate the role of inflammatory spine disease in patients with chronic back pain. The contribution of imaging modalities for the diagnostic evaluation of back pain is discussed. A systematic literature search based on the classification of seronegative spondyloarthropathies and rheumatoid arthritis was performed. The results of this search and the experiences in a large collective of rheumatological patients are analyzed. The prevalence of rheumatoid arthritis (1-2%) is comparable to that of spondyloarthropathies (1.9%). The etiology of these entities is not fully elucidated. Magnetic resonance imaging is increasingly used for early detection and surveillance of therapy with TNF-{alpha} antagonists. Bone marrow edema, which is only detectable with MRI, represents an early sign of inflammation. Therapy with TNF-{alpha} antagonists is based on clinical and laboratory criteria, and signs of inflammation in MRI. MRI is useful for assessment of the ...

2006-06-15

5

Feasibility study for new ecolabels for the product group: Wood pellet firings. Final report; Machbarkeitsstudie fuer neue Umweltzeichen fuer die Produktgruppe: Holzpelletfeuerungen. Endbericht  

Energy Technology Data Exchange (ETDEWEB)

This assessment is a feasibility study according to ISO 14024. It deals with the question whether an ecolabel is suitable for wood pellet heating systems and how concrete criteria for an ecolabel for wood pellet heating plants could be specified. The study begins with a comprehensive market analysis in order to identify possible plants for which an ecolabel would make sense. In the main part of the study, the environmental relevance of the chosen plants is analysed. For this analysis, plant manufacturers were interviewed and a comparison between wood pellet heating systems and heating systems which use gas, oil or wood was carried out. On the basis of this analysis, it was possible to derive a number of criteria which were discussed with company representatives and other experts in this field. As a result of this dialogue and the investigation process as a whole, the introduction of an ecolabel for wood pellet heating plants can be recommended. Wood pellet heating systems are ...

2002-07-01

8

Computed tomography in AIDS-related thoracic diseases; Computertomographie AIDS-assoziierter Thoraxerkrankungen  

Energy Technology Data Exchange (ETDEWEB)

Pulmonary infections and tumors are a major cause of death in patients with AIDS. The combination of clinical, radiological, laboratory, and pathohistological data helps to narrow the spectrum of differential diagnoses or even allows a specific diagnosis in many patients. Nevertheless, an accurate diagnosis should be obtained as soon as possible during the clinical course of the illness to initiate treatment in time. Computed tomography (CT) has proven to provide promising results in the diagnosis of AIDS-related throacic diseases. The aim of this paper was to demonstrate the diagnostic capacities of CT in the context of particular AIDS-related thoracic pathologies. Additional information on the spectrum of pathological agents and on differential diagnostic signs is summarized. (orig.) [Deutsch] Pulmonale Infektionen und Tumore sind eine wesentliche Todesursache bei Patienten, die am erworbenen Immunmangelsyndrom AIDS leiden. In den meisten Faellen gelingt es, durch Zusammenschau ...

1996-07-01

9

Parameters for viable process combinations; Randbedingungen fuer sinnvolle Verfahrenskombinationen  

Energy Technology Data Exchange (ETDEWEB)

The following parameters merit examination in determining the viability of process combinations: conceptual and technical soundness, environmental acceptability, energy balance, flexibility, costs, economic risk potential. The present contribution on this subject is not intended to take the place of or cover the scope of single-case studies. In practice, viability studies on process combinations have to deal with concrete plans involving precisely defined material flow balances, emissions, costs etc. The present paper therefore only presents the basic principles of this type of study. [Deutsch] Folgende Randbedingungen fuer sinnvolle Verfahrenskombinationen sind zu untersuchen: - konzeptionelle und technische Stimmigkeit, - Umweltvertraeglichkeit, - energetische Bilanz, - Flexibilitaet, - Kosten, - oekonomisches Risikopotential. Nun kann dieser Beitrag zum Thema keine Einzelfallbetrachtung ersetzen bzw. abdecken. Im Rahmen einer echten Pruefung auf `Sinnhaftigkeit` ...

1998-09-01

10

Development of a new technology for preparing samples for transmission electron microscopy (TEM) on the basis of ion fine beam processing; Entwicklung einer neuen Technologie zur Probenpraeparation fuer die Transmissions-Elektronenmikroskopie (TEM) auf der Basis der Ionenfeinstrahlbearbeitung  

Energy Technology Data Exchange (ETDEWEB)

The goal of this project was to develop a new technology for preparing samples for transmission electron microscopy (TEM) on the basis of ion fine beam processing. For this purpose processes of ion-beam-assisted removal (sputtering), separation, sample handling and ion-beam-assisted chemical etching as well of system-inherent components were examined. As an alternative to a Ga-source a liquid-metal ion source based on a AuGeSi alloy was developed, characterised and used in the FIB 4400. [German] Aufgabe des Projektes war die Entwicklung einer neuen Technologie zur Probenpraeparation fuer die Transmissions-Elektronenmikroskopie (TEM) auf der Basis der Ionenfeinstrahlbearbeitung. Dazu wurden Prozesse der ionenstrahlgestuetzten Abtragung (Sputtern), der Abscheidung, des Probenhandling, des ionenstrahlgestuetzten chemischen Aetzens sowie systemeigener Komponenten untersucht. Als Alternative zur Ga-Quelle wurde eine Fluessigmetall-Ionenquelle auf der Basis ...

2001-08-01

11

Comparative study of twin-screw superchargers for small capacity Otto-cycle engines; Schraubenlader im Vergleich der Aufladegeraete fuer kleinvolumige Ottomotoren  

Energy Technology Data Exchange (ETDEWEB)

In the last few years the supercharging of Otto-cycle-engines has regained popularity, as demonstrated by a number of series-production engines. After listing the aims to be met by a modern supercharger the paper describes the technical status of mass-produced or close to production superchargers. This is followed by a comparative evaluation of the systems, enabling the reader to select possible solutions for a projected supercharger-engine-system by means of a comparison chart. The paper is concluded by a list of possible directions for further development and additional potential for twin-screw superchargers. (orig.) [German] In neuerer Zeit hat die Aufladung von Ottomotoren wieder ein verstaerktes Interesse gefunden, das sich auch in einer Anzahl serienmaessig gefertigter aufgeladener Motortypen wiederspiegelt. Der vorliegende Beitrag beschreibt, nach einer Darstellung der Anforderungen an ein modernes Aufladegeraet, den Stand der Technik ...

2001-07-01

12

The results of physical modeling of flow in an axial cyclone combustion chamber; Ergebnisse physikalischer Modellierung der Stroemung in einer Axialzyklonbrennkammer  

Energy Technology Data Exchange (ETDEWEB)

The isothermal flow field for the axial cyclone has been experimentally determined. The velocity fields are used for determination particle paths (particle removal and suspended state), and inter alia of heat and mass transfer processes in the axial cyclone combustion chamber. The results are extremely significant as input value approximations for mathematical modelling, since experimentally obtained results are indispensable for complex flows and geometries. (orig.) [Deutsch] Es ist fuer den Axialzyklon experimentell das isotherme Stroemungsfeld ermittelt. Die Geschwindigkeitsfelder dienen zur Ermittlung der Partikelbahnen (Partikelabscheidung, Schwebebedingung), der Waerme- und Stoffuebertragungsprozesse u.a. in der Axialzyklonbrennkammer. Die Ergebnisse sind als Startwertnaeherung bei einer mathematischen Modellierung sehr wichtig, da bei komplexen Stroemungen und Geometrien versuchstechnische Ergebnisse unumgaenglich sind. (orig.)

1994-12-31

13

Structure and properties of stainless steels after plasma immersion ion implantation and plasma nitriding; Struktur und Eigenschaften nichtrostender Staehle nach einer Plasmaimmersionsionenimplantation und einer Plasmanitrierung  

Energy Technology Data Exchange (ETDEWEB)

Stainless steels can be nitrided at temperatures {<=}400 C to increase their hardness and wear resistance without a decreasing of their excellent corrosion resistance. Structure and properties of the surface layers produced by plasma nitriding and plasma immersion ion implantation in this temperature range were tested. There are negligible differences in the structure of the produced surface layers in spite of different interaction principles of the used technologies. However there are clear differences between the case of different steels. The case of ferritic chromium steels mainly consists of {epsilon}-nitride. Whereas the cases of austenitic and ferritic austenitic steels are characterized by expanded austenite. The corrosion resistance of the steels is reduced by nitriding only, if evident CrN-formation occurs. (orig.) 11 refs.

1999-08-01

14

Burning ice. Methane hydrate on the sea floor; Brennendes Eis. Methanhydrat am Meeresgrund  

Energy Technology Data Exchange (ETDEWEB)

In certain regions of the sea floor, water and methane from organic depositions have turned into a burnable form of ice, i.e. methane hydrates which contain more stored energy than all fossil fuel reserves. If they should desintegrate as a result of global heating, methane will be released and will contribute to further global heating. [Deutsch] Im Boden bestimmter Meeresregionen haben sich Wasser und Methan aus organischen Ablagerungen zu einer brennbaren Form von Eis vereinigt. Diese Methanhydrate speichern mehr Energie als alle fossilen Brennstoffvorraete. Wenn sie sich bei einer globalen Erwaermung zersetzen, koennte das entweichende Methan als Treibhausgas die Erde noch mehr aufheizen. (orig.)

1999-06-01

15

Galvanic primary cell with an alkaline electrolyte and an air electrode. Galvanisches Primaerelement mit alkalischem Elektrolyten und einer Luftelektrode  

Energy Technology Data Exchange (ETDEWEB)

According to the invention, a zinc foil is arranged between the negative electrode of a zinc/air battery (round cell) and the expansion space compensating for the reactive increase in volume of the zinc powder. This zinc foil functioning as a stop diaphragm particularly ensures, from the very onset, that the zinc filling has a density and compactness necessary for good electronic conductance.

1986-11-06

16

Das kalte Licht der Olefine  

British Library Electronic Table of Contents (United Kingdom)

Abstract Der folgende Artikel setzt die Reihe unserer ChiuZ-Beitrge zur Chemi- und Biolumineszenz mit einer interessanten und neuen experimentellen Arbeit zum -kalten Licht- spezieller ungesttigter Verbindungen fort, deren Anwendung auch in der modernen Zeit der Nanotechnologie im biochemischen bzw. medizinisch-chemischen Labor vllig neue Akzente gesetzt hat.

2011-01-01

17

Berechnung Stationaerer und Niederfrequent Instationaerer Stroemungen in Einer Dampfturbinen-Endstufe (Calculation of Stationary and Low Frequency Unsteady Flows in a Steam Turbine End Stage).  

Science.gov (United States)

A numerical method for the calculation of unsteady, inviscid turbomachine flow in the transonic velocity range is described. The calculation of complete stages is possible. If the flow layer geometry is given, the flow field can be determined by independe...

1986-01-01

18

Aspects of landscaping in case of constructing new HV transmission line. Landschaftsschutzaspekte beim Bau einer neuen Hochspannungsleitung  

Energy Technology Data Exchange (ETDEWEB)

When constructing new high-voltage transmission lines landscape aspects play a more and more important role. The project described is particularly interesting as it demonstrates that it is possible to find acceptable solutions for everyone if all partners are prepared to make concessions. The article also describes a new concept for the connection of concrete tower elements. (orig.).

1991-01-23

19

26 years of operating experience with a boiler drum manufactured from a high-temperature copper-nickel-molybdenum steel. 26 Jahre Betriebserfahrungen mit einer Kesseltrommel aus einem warmfesten Kupfer-Nickel-Molybdaen-Stahl  

Energy Technology Data Exchange (ETDEWEB)

The creep behaviour of boiler drums of CuNiMo steels depends on the ratio of the alloys, the heat treatment and the processing technology. Reduction in deformability must be expected but, under optimum conditions, this does not lead to a critical material condition. The appropriate material tests are indispensable. (orig.)

1993-05-01

20

The new WHO classification of brain tumors. Radiological aspects of 4 new tumor entities; Die revidierte WHO-Klassifikation der Hirntumoren. Radiologische Aspekte unter besonderer Beruecksichtigung von vier neuen Tumorentitaeten  

Energy Technology Data Exchange (ETDEWEB)

Characterisation of the classification of brain tumours authorised by the WHO. Method of appraisal: This classification was revised and published in its second version. In the revision, some tumours were regrouped histogenetically and some tumour variants were added. Radiologically relevant changes of the classification include the differentiation of four new tumour entities that are easily distinguished by MR imaging. These four tumours belong to the group of childhood tumours or tumours occurring in early adulthood and are characterized by a good prognosis after extirpation. Results of appraisal: Central neurocytomas are small-cyst ventricular tumours associated with the foramen of Monroi and show moderate contrast enhancement. Infantile desmoplastic gangliogliomas/astrocytomas commonly consist of a solid tumour portion related to the leptomeninges with pronounced contrast enhancement and a typically very large cyst. Pleomorphic xanthostrocytomas are circumscribed cortical tumours ...

1997-06-01

21

QUEOS, a simulation-experiment of the premixing phase of a steam explosion with hot spheres in water base case experiments  

Energy Technology Data Exchange (ETDEWEB)

This report describes the QUEOS facility and gives the results of the first test series performed up to 6/1995. The premixing phase of a steam explosion is investigated experimentally with simulant materials. The transient three-dimensional multi-component interaction of molten corium with water is studied using a large number of small solid spheres at temperatures up to 2300 C. The objective of the experiments is to establish a data base for testing the models of heat and momentum transfer in multi-fluid codes as well as the code`s capability to correctly describe multiphase flows. The experiments have the advantage that the diameter of the `coarse melt fragments` are known and that detailed measurements can be performed without the danger of a steam explosion. In this first series of experiments up to 10 kg of spheres (max. 24000 pieces) were used. The spheres, made of molybdenum or zirconia, were heated to temperatures up to 2000 C and are discharged into 0.5 m{sup 3} of saturated ...

1996-04-01

22

In vitro investigation of biological and technical prosthetic heart valves in MRI: evaluation of possible deflection and heating of the implants; In-vitro-Untersuchung von biologischen und technischen Herzklappenprothesen im MRT: Beurteilung moeglicher Anziehung und Erhitzung der Implantate  

Energy Technology Data Exchange (ETDEWEB)

Purpose: In vitro evaluation of possible deflection and heating of present-day prosthetic heart valves, 12 technical and 5 biological, were investigated using a 1.5 Tesla Siemens Vision system. Deflection was measured at the edge of a 1.5 Tesla superconducting magnet. Each valve was then submerged in a vial of a 1/1 electrolyte solution and temperature was measured before and after imaging with a turbo-spin-echo sequence (TR 5200 ms, TE 138 ms, Flip angle 180 C, acquisition time 10.5 minutes, length of echo train 29). MR imaging was performed with phase encoding parallel and perpendicular to the plane of the valves. Results: None of the investigated prosthetic heart valves was deflected. The maximal observed temperature rise was 0.5 C. During MR investigation of the prostheses, artifacts caused by metallic parts were less evident using a spin-echo sequence than a gradient-echo sequence. Conclusions: Patients with the tested present-day prosthetic heart valves can be safely imaged by ...

2000-02-01

23

High-dose radiation therapy for inoperable non-small cell lung cancer without mediastinal involvement (clinical stage N0, N1)  

Energy Technology Data Exchange (ETDEWEB)

To evaluate the usefulness of radiation therapy alternative to surgery for clinical N0-N1 non-small cell lung cancer (NSCLC). From 1976 through 1989, 116 patients with NSCLC without mediastinal involvement were treated with definitive radiation therapy alone at Gunma University Hospital. All patients were treated with once-daily standard fractionation using 10 MV X-rays. The total dose ranged from 60 Gy to 80 Gy. The actuarial 2- and 5-year survival rates of the entire group were 43% and 20%, respectively with a median survival time of 19 months. The survival of 76 patients with stage T2 tumors was significantly better than that of 28 patients with T3 tumors (mean survival time 21 versus 15.5 months; p<0.05). Sixty-two patients with tumors less than 5 cm in diameter had a 2-year progression rate of 20%, in comparison with 39% of 54 patients with tumors greater than 5 cm. The difference of survivals for these 2 groups was statistically significant. Twelve patients given a total dose ...

1996-09-01

24

The new BMW 4-cylinder engine in the 318i; Der neue BMW Vierzylindermotor im 318i  

Energy Technology Data Exchange (ETDEWEB)

The BMW four-cylinder two-valve engine was first launched in September 1987 as a 1.8 l engine and was described in detail in [1]. After initial optimisation for model year 94, four years later the engine has undergone a complete technical revision. From model year 98, the four-cylinder two-valve engine with appropriate exhaust emission technology will satisfy the EU3 class for exhaust emissions. (orig.) [Deutsch] Der BMW Vierzylinder-Zweiventilmotor wurde im September 1987 als 1,8-l-Motor erstmals vorgestellt und in [1] ausfuehrlich beschrieben. Nach einer ersten Optimierungsueberarbeitung zum Modelljahr 1994 wurde nun eine grundlegende technische Ueberarbeitung vorgenommen. Der Vierzylindermotor mit Zweiventiltechnik erfuellt als Antriebsaggregat in Verbindung mit einer entsprechenden Abgastechnik bereits ab Modelljahr 1998 die EU 3-Stufe fuer Abgasemissionen. (orig.)

1998-05-01

25

The influence of the layout-admission pressure loss on the control-statical properties of steam turbines; Der Einfluss des Auslegungs-Einstroemdruckverlustes auf die regelstatischen Eigenschaften von Dampfturbinen  

Energy Technology Data Exchange (ETDEWEB)

The complete determination of stroke/throughput curves at steam turbines for arbitrary valve positions usually only follows after the fundamental layout of the control valves, of the possible nozzle segments and of the turbine blading. A general fundamental equation and some design norms based on it are presented which may serve already before a fluidic layout of the turbine in detail as an optimizing predetermination of the properties concerning pressure loss and control statics of the metering components in the admission area. (orig.) [Deutsch] Die vollstaendige Bestimmung der Hub-/Durchsatzkurven an Dampfturbinen fuer beliebige Ventilstellungen erfolgt ueblicherweise erst nach der Grundauslegung der Stellventile, etwaiger Duesensegmente und der Turbinenbeschaufelung. Es werden eine allgemeine Grundgleichung und einige auf ihr aufbauende Entwurfsregeln angegeben, die zu einer optimierenden Vorabbestimmung der druckverlustbezogenen regelstatischen Eigenschaften ...

1997-06-01

26

Technology and cost of waste fermentation with subsequent composting as an alternative to conventional composting; Technik und Kosten einer Restmuellvergaerung mit anschliessender Nachrotte als Alternative zur ausschliesslichen Rotte  

Energy Technology Data Exchange (ETDEWEB)

The author investigates whether waste fermentation is an economically feasible alternative to composting. Decisions on projects and sites should not be made until the basic problems of feasibility and economic efficiency are solved. [German] In Anbetracht der derzeitigen Situation bei der Restmuellbehandlung, in der die mechanisch-biologische Behandlung als Alternative zu einer rein thermischen Behandlung immer mehr an Bedeutung gewinnt, stellt sich immer haeufiger die Frage, ob die Restmuellvergaerung eine Alternative zur ausschliesslichen Restmuellrotte darstellt. Diese Frage muss zunaechst prinzipiell aus Sicht der technischen Machbarkeit und von der Sinnhaftigkeit, hier vor allem von der Kostenseite her, betrachtet werden. Erst daran anschliessend lassen sich projekt- und standortbezogene Betrachtungen anstellen. Hinsichtlich der technischen Machbarkeit laesst sich im wesentlichen auf den grosstechnischen Erfahrungen der letzten 8 Jahre bei der ...

2002-07-01

27

TENSOMAX - a retrofit thermal stress monitoring system for steam turbines; TENSOMAX - Eine nachruestbare Ueberwachung der thermischen Beanspruchung von Dampfturbinen  

Energy Technology Data Exchange (ETDEWEB)

TENSOMAX enables on-line monitoring of the thermal stress of the shaft to be performed in steam turbines, for which the TURBOMAX probe cannot be installed near the critical area of the shaft. TENSOMAX provides an alternative to the TURBOMAX with a slightly reduced accuracy of the simulation of the temperature distribution in the shaft. The high value placed on the operational performance of TENSOMAX remains, viz. that even with older turbines, and particularly in the case of turbines rehabilitated with a new shaft, careful and transparent operation is assured. (orig.) [German] Die Einrichtung TENSOMAX ermoeglicht eine Ueberwachung der thermischen Beanspruchung der Welle bei Dampfturbinen, bei denen die TURBOMAX-Sonde in der Turbine nahe der kritischen Stelle der Welle nicht einsetzbar ist. Daher stellt der TENSOMAX unter Beruecksichtigung minimaler Ungenauigkeit aufgrund der Nachbildung der Waermeuebergangszahl eine vorteilhafte Alternative zum TURBOMAX dar. Der betriebsmaessig ...

2000-07-01

28

Risk assessment of equipment of power supply industry; Risk-Assessment von Betriebsmitteln der elektrischen Energieversorgung  

Energy Technology Data Exchange (ETDEWEB)

The article deals with the following topics: reliability calculation as a basis of a maintenance strategy leads to the knowledge which equipment seems to be critical in the context of a supply interruption; procedure of a risk management; information for a risk assessment: probability of an equipment malfunction, reliability calculation on the system level, failure cost, maintenance cost, further conditions. The article shows an example for a calculation. [German] Die Zuverlaessigkeitsberechnung als Grundlage einer Instandhaltungsstrategie fuehrt zu der Kenntnis, welche Betriebsmittel kritisch im Hinblick auf eine Versorgungsunterbrechung sind. Eine anschliessende Risikobetrachtung schliesst deshalb neben der Betrachtung der nichtgelieferten Energie auch die uebrigen Kosten einer Stoerung ein, die mit den finanziellen Aufwendungen fuer eine Instandhaltung zu vergleichen sind. Im Folgenden wird ein Vorschlag fuer eine Risikobewertung von ...

2004-10-15

29

Practice-oriented design of speed and output power controllers for steam turbines; Praxisgerechte Auslegung von Drehzahl- und Leistungsreglern fuer Dampfturbinen  

Energy Technology Data Exchange (ETDEWEB)

Within the context of practice-oriented constraints the speed and output power control of power plant turbines represents a big challenge for engineers for designing low order controllers with only a few parameter settings and in order to meet the requirements of the Deutsche Verbundgesellschaft. The results of a detailed study of the current standard and an improvement of the speed dynamic for load rejections are shown. (orig.) [German] Die Regelung der Drehzahl und die Leistung von Kraftwerksturbinen stellt im Rahmen von praxisorientierten Nebenbedingungen, wie z.B. dem Einsatz von Reglern geringer Ordnung mit wenigen Einstellparametern und den Vorgaben der Deutschen Verbundgesellschaft, eine grosse Herausforderung fuer den Entwicklungsingenieur dar. Die Ergebnisse einer ausfuehrlichen Untersuchung des bisherigen Standards und einer Verbesserung der Drehzahldynamik bei sogenannten Abfangpruefungen werden vorgestellt. (orig.)

1999-07-01

30

Optimization of district heating power stations; Optimierung von Blockheizkraftwerken  

Energy Technology Data Exchange (ETDEWEB)

A computer program for optimization of modular cogeneration plants is introduced. Computer calculation fundamentals are discussed referring to examples which elucidate the verification of the calculated data by measured data or empirical values. The results obtained as one optimizes plants by varying their size or by splitting them into modules are introduced referring to examples. Sensitivity analyses are made to investigate the influence of parameters such as fuel prices, electricity tariffs and interest rates. (orig.) [Deutsch] Im vorliegenden Beitrag wird ein Computerprogramm zur Optimierung von BHKW-Anlagen vorgestellt. Zunaechst werden in einem ersten Schritt die Berechnungsgrundlagen an einem Beispiel in Hinblick auf ihre Ueberpruefung durch Messdaten oder durch Erfahrungswerte diskutiert. Dann werden in einem zweiten Schritt exemplarisch die Ergebnisse einer Optimierung durch Variation der Gesamtanlagengroesse auf Aufsplittung der Anlage in Module ...

1994-10-01

31

Low-frequency fields - sources and exposure; Niederfrequente Felder - Quellen und Exposition  

Energy Technology Data Exchange (ETDEWEB)

The author briefly discusses definition of terms, gives an introduction to measurement techniques and describes the characteristics of various low-frequency fields and their causes using typical examples: natural electric fields (thunderstroms), natural magnetic fields, technical electric constant fields (urban transportation, households), static magnetic fields (urban transportation, nuclear magnetic resonance imaging), technical electric alternating fields (high-voltage transmission lines, households), and magnetic alternating fields (high-voltage transmission lines). The author discusses both occupational exposure and that of the general public while underpinning his statements by numerous tables, measurement diagrams and charts. (Uhe) [Deutsch] Nach einer kurzen Diskussion der Begriffsdefinitionen und einer Einfuehrung in die Messtechnik werden die Charakteristika verschiedener niederfrequenter Felder und ihre Ursachen anhand typischer ...

1993-06-01

32

Hydro power in the German system of energy supply; Wasserkraft im Energiesystem Deutschland  

Energy Technology Data Exchange (ETDEWEB)

The technical potentials of electric power generation from hydro power in Germany, the current harnessing of hydro power, its costs, and certain characteristic quantities reflecting its effects on the environment are described. These diverse characteristic quantities are compared with those of other renewable and fossil energy sources used to generate electricity. On this basis, opportunities for extending the use of hydro power in Germany and its limits are discussed. (orig.) [Deutsch] Das Ziel der folgenden Ausfuehrungen ist, die technischen Potentiale und deren derzeitige Nutzung, die Kosten und bestimmte die Umwelteffekte beschreibende Kenngroessen einer Stromerzeugung aus Wasserkraft in Deutschland darzustellen. Diese unterschiedlichen Kenngroessen werden anschliessend mit denen anderer regenerativer Energien und fossiler Energietraeger zur Stromerzeugung verglichen. Ausgehend davon werden die Moeglichkeiten und Grenzen einer ...

1997-12-31

33

Development of an electrically rechargeable zink/air demonstration module; Entwicklung eines elektrisch wiederaufladbaren Zink-Luft-Demonstrationsmoduls  

Energy Technology Data Exchange (ETDEWEB)

A team at the Paul Scherrer Institute (PSI) recently achieved a breakthrough in the development of an environment-friendly and rechargeable battery with novel electrodes. The energy storage density of a rechargeable 12 V/20 Ah zinc/air battery could be increased to 100 watt hours per kilogramme - three times as much as conventional lead accumulators. 20-Ah cells could be charged and discharged 55 times in 1000 hours without any loss of capacity worth mentioning. This is a remarkable cycle stability. (orig.) [German] Einem Team des Paul Scherrer Instituts (PSI) ist kuerzlich bei der Entwicklung einer umweltfreundlichen und wiederaufladbaren Batterie mit neuartigen Elektroden der Durchbruch gelungen. Dabei konnte die Energiespeicherdichte einer wiederaufladbaren 12 V/20 Ah-Zink-Luft-Batterie auf 100 Wattstunden pro Kilogramm gesteigert werden - dreimal soviel wie bei konventionellen Bleiakkumulatoren. 20-Ah-Zellen konnten in 1000 Stunden ohne ...

1999-10-01

34

Cogeneration process for small and medium-sized industrial plants; CO-Generation-Process fuer kleinere und mittlere Industrieanlagen  

Energy Technology Data Exchange (ETDEWEB)

Industrial companies are being forced by increasingly restrictive environmental legislation to implement power station technology which is environmentally compatible and which conserves scarce resources. Gas and steam turbine power stations have been causing a sensation in this field for some time. This article gives an introduction to gas and steam turbine power stations in the 4 MW to 30 MW size range. The designs of the plants described here not only provide for electricity generation by gas and steam turbines however, but also designs specific to particular companies for process steam and district heating supply. (orig.) [Deutsch] Durch immer restriktivere Umweltschutzgesetze werden die Industrieunternehmen zu einer umwelt- und ressourcenschonenden Kraftwerkstechnik gedraengt. Auf diesem Gebiet sorgen nun seit geraumer Zeit GuD-Kraftwerke fuer Furore. In diesem Beitrag werden GuD-Kraftwerke in einer Groessenordnung zwischen 4 MW und 30 MW ...

1993-12-31

35

Application of fluidized-bed combustion plants in the field of energy technology; Einsatz von Wirbelschichtfeuerungsanlagen in der Energietechnik  

Energy Technology Data Exchange (ETDEWEB)

In the future fossil fuelled power plants are realised/laid down as combined cycle power plants with high current generation efficiencies. The method of pressure fluidized-bed combustion with downstream hot gas cleaning is going to compete with methods combined with a pressure coal gasification or a pressure dust combustion. The advantages of the pressure fluidized bed combustion are the simpler method set-up and consequently lower investment costs. (orig./CD) [Deutsch] Kohlegefeuerte Kraftwerke werden zukuenftig als kombinierte Gas/Dampfturbinen-Kraftwerke mit hohen Stromerzeugungswirkungsgraden ausgefuehrt werden. Das Verfahren der Druckwirbelschichtverbrennung mit nachgeschalteter Heissgasreinigung und Rauchgasturbine wird dabei mit Verfahren mit einer vorgeschalteten Kohledruckvergasung oder mit einer Druckstaubfeuerung konkurrieren. Die Vorteile der Druckwirbelschichtverbrennung liegen dabei auf dem insgesamt einfacheren Verfahrensaufbau ...

1993-12-31

36

Theoretical investigations of strength of a flexible tube made of NiTi; Festigkeitstheoretische Untersuchungen einer flexiblen Huelse aus NiTi  

Energy Technology Data Exchange (ETDEWEB)

A flexible, steerable tube (distal end) of an endoscope for the application in the laparoscopic surgery has been analyzed by means of the finite-element-method (FEM). The unusual mechanical and thermal features of the used shape memory alloy (SMA) of NiTi were taken in account. The analyses showed that the strains remain in the super-elastic region up to the maximum bending of 90 and no plastic deformations occur. The application of the shape optimization (CAO) made possible finding the optimal structure of the distal end and therefore powerful reducing the maximum strains in the critical regions. (orig.)

2000-04-01

37

Much news in electric cars; Es tut sich viel bei Elektromobilen  

Energy Technology Data Exchange (ETDEWEB)

There is much interest worldwide in low-emission, low-noise electric cars. Modern vehicles with advanced technology are an interesting alternative to conventional cars. (orig.) [Deutsch] Das Interesse an den emissionsfreien und leisen Elektroautos ist weltweit ungebrochen. Die heute verfuegbaren Fahrzeuge zeigen die betraechtlichen, in den letzten Jahren erzielten Fortschritte, die sie fuer immer mehr Anwender zu einer beliebten Alternative zur Benutzung des konventionellen Autos machen. (orig.)

1998-06-12

38

Heating and cooling with the building mass; Mit der Gebaeudemasse heizen und kuehlen  

Energy Technology Data Exchange (ETDEWEB)

A Paderborn group of builder-owners decided in favour of so-called concrete core activation or isothermal component tempering as an alternative to conventional air conditioning. Results are now available for the first year of operation. [German] Am eigenen Neubau hat eine Paderborner Bauherrengemeinschaft die sogenannte Betonkernaktivierung - oder wie es die Bauherren nennen, isotherme Baukoerpertemperierung - als Alternative zu einer konventionellen Klimaanlage installiert. Inzwischen liegen die Messergebnisse von der ueber einjaehrigen Betriebszeit vor. (orig.)

2000-08-01

39

Correct monitoring of stationary battery systems; Stationaere Batteriesysteme richtig ueberwacht  

Energy Technology Data Exchange (ETDEWEB)

There are many applications that necessitate reliable and permanent power supply, e.g. power stations, airports, computer centers or hospitals. The stationary battery systems must be monitored by efficient systems, e.g. Batlog. (orig.) [Deutsch] Viele Anwendungen verlangen eine permanent verfuegbare und zuverlaessige Stromversorgung. Kraftwerke, Flughaefen, Rechenzentren oder Krankenhaeuser muessen ihre Prozesse auch bei einem Netzausfall oder einer Versorgungsunterbrechung weiterbetreiben. Dies gelingt nur, wenn sich der entsprechende Energiespeicher in einsatzbereitem Zustand befindet. Die Ueberwachung der stationaeren Batterieanlagen erfordert leistungsfaehige Systeme wie Batlog. (orig.)

1998-10-01

40

Condition Monitoring in Power Stations; Condition Monitoring im Kraftwerk  

Energy Technology Data Exchange (ETDEWEB)

Maintenance of power stations so far operated on the concept of using or extending the expected service life of a machine or plant as far as possible in order to avoid early and costly replacement. This was done by means of time-oriented maintenance, inspection and repair, otherwise called preventive maintenance. A European study on maintenance methods totals the cost of these measures at between 140 to 200 billion DM. One way of reducing these costs is 'predictive maintenance'. Estimated savings are about 8 percent or between 12 and 16 billion DM per year. Predictive maintenance identifies irregulaties of machine parts at an early point in time by means of condition monitoring and can help to cut costs: unplanned repairs can be avoided; repairs can be fitted into production schedules; production will not be disturbed to to unforeseen repairs, optimised spare part warehousing helps to cut costs. Predictive maintenance aims at keeping availability high, give maximum ...

1998-07-01

41

Wood fires are coming back. Fuel pellets are gaining acceptance; Holzfeuer erleben Renaissance. Brennstoff Pellets findet immer mehr Anhaenger  

Energy Technology Data Exchange (ETDEWEB)

Wood is currently having a renaissance as a domestic fuel. Wood pellets, usually about 8 mm in diameter and 40 mm long and produced from sawmill and wood processing residues by pressing without binders, are gaining general acceptance. According to a market analysis of Solar Promotion GmbH, Pforzheim, about 4,800 pellet-fuelled heating systems with automatic fuel supply and with a total thermal capacity of 35 kW are in operation in Germany, and 2000 new ones were installed in 2000. [German] Holz als Brennstoff erlebt in vielen Heizkellern und Kaminen eine Renaissance. Und zwar nicht in Form von Holzscheiten, sondern als kleine Presslinge, meist mit einem Durchmesser von acht und einer Laenge von bis zu 40 Millimetern. Als Abfallprodukt von Saegewerken und Holz verarbeitenden Betrieben werden die so genannten Pellets unter hohem Druck und ohne Bindemittel wie beispielsweise Leim hergestellt. Und dieser neue Brennstoff findet immer mehr Anhaenger. So sind im ...

2002-03-01

42

Total emissivity and spectral emissivity of high-temperature materials; Gesamtemissionsgrad und spektraler Emissionsgrad von Hochtemperaturmaterialien  

Energy Technology Data Exchange (ETDEWEB)

A new emissivity measurement device with inductive sample heating is described. The disc shaped samples can be measured between 800 C and 2000 C in vacuum or in each available gas atmosphere. Two kinds of surface temperature measurement methods are described, one by measuring in a blackbody hole and one by measuring at the surface without additional measures to correct emissivity. Total normal and spectral emissivity at wavelengths between 0,5 {mu}m and 8,3 {mu}m of various high temperature materials like platinum and Pt-Rh-alloys, siliconcarbide and molybdenum disilicide have been measured. From the investigated materials a few have been selected as reference samples for comparative emissivity measurements fullfilling the requirement of stability on air up to 400 C to 1000 C in order to ensure reproducibility of the results at different measurement conditions in air and in vacuum. (orig.) [Deutsch] Der Aufbau einer neuen Messapparatur fuer Emissionsgradmessungen ...

1998-05-01

43

Substitution of old single flat gas heating systems: Comparision of modernization possibilities; Ersatz alter Gasetagenheizungen: Vergleich von Modernisierungsvarianten  

Energy Technology Data Exchange (ETDEWEB)

The research project's objective is to create a decision help for owners of residential buildings for several families regarding the renewal of decentralized heating and warm water preparation systems in the flats. The focus lies on a comparison of the costs of typical systems on the basis of a full cost calculation. This is done by taking into consideration the intentions of residential building companies like the reduction of additional costs to be paid by the tenants (both for social reasons and to make the flats easier to rent), low investment costs, low maintenance costs, energy saving, tenants' claims for comfort and acceptance by the tenants, economical reasons, especially regarding flats fully amortized (activation in the balance sheet). In addition to the quantitative comparison, the advantages and disadvantages of the different systems were also compared to one another from the qualitative point of view. [German] Ziel des Forschungsvorhabens ist die ...

2004-04-01

44

Offshore wind power. Position paper of the Minister of the Environment; Windenergienutzung auf See. Positionspapier des Bundesministeriums fuer Umwelt, Naturschutz und Reaktorsicherheit zur Windenergienutzung im Offshore-Bereich  

Energy Technology Data Exchange (ETDEWEB)

The position paper will provide the basis for further strategies on offshore wind power development in consideration of ecological and conservation aspects. [German] Das Positionspapier des Bundesministeriums fuer Umwelt, Naturschutz und Reaktorsicherheit (BMU) einschliesslich des Umweltbundesamtes (UBA) und des Bundesamtes fuer Naturschutz (BfN) ist Ergebnis der Arbeiten der BMU-Projektgruppe 'Windenergienutzung im Offshore-Bereich im Hinblick auf die BMU-Anliegen'. Es beschreibt den derzeitigen Stand einer Strategie zur umwelt- und naturvertraeglichen Erschliessung der Windenergienutzung auf See (Offshore). Es bildet die Grundlage fuer die Weiterentwicklung dieser Strategie und dabei insbesondere zur Abstimmung mit den Anliegen anderer Bundesressorts und den Kuestenlaendern, sowie zur intensiveren Einbeziehung beteiligter Verbaende und Fachkreise. Vor dem Hintergrund der zur Genehmigung eingereichten Antraege fuer Offshore-Windparks, mangelnder ...

2001-07-01

45

Microbiologically influenced corrosion of carbon and stainless steel pipes; Mikrobiologisch beeinflusste Korrosion an Rohrleitungen aus unlegierten und hochlegierten nichtrostenden Staehlen  

Energy Technology Data Exchange (ETDEWEB)

About ten years ago microbiologically influenced corrosion manifested on stainless steel pipes used with river water for cooling a chemical plant. The pipe material was similar to Type 316 L. After only six weeks of operation pinhole leaks occurred nearly simultaneously at several welded joints of the pipe. The material degradation was simulated in laboratory and field corrosion tests. Microbiologically influenced corrosion failures also appeared on the pipes of a tubular heat exchanger of duplex steel Type 31803 and on carbon and stainless steel pipes in industrial waste water purification plants after these plants had been modernized with a biological purification unit. The basics of microbiologically influenced corrosion phenomena and typical corrosion failures of pipes will be described. (orig.) [German] Vor etwa zehn Jahren sind in einer neu errichteten chemischen Produktionsanlage an einer mit Flusswasser beaufschlagten Kuehlwasserleitung ...

1999-09-01

46

Injured lateral ankle ligaments: technique and assessment of MRI; Verletzungen des Aussenbandapparates am oberen Sprunggelenk: Untersuchungstechnik und Nachweis mittels MRT  

Energy Technology Data Exchange (ETDEWEB)

56 patients with the clinical diagnosis of sprained ankles were investigated. Evaluation of the anterior (AFTL) and posterior fibulotalar ligament (PFTL) was performed with the foot in dorsiflexion (20 ) and of the fibulo calcanear ligament (FCL) in plantarflexion (45 ). Axial T{sub 1}w-SE and T{sub 2}w-TSE images were obtained. Full-length visualisation of ligmaments in one slice and the extent of injury were evaluated. 12 ankle injuries were confirmed by operation. With MRI full-length visualisation of lateral ankle ligaments was possible in 86%. A partial/complete rupture of the AFTL was noticed in 33/64% and of the FCI in 29/39%, and of the PFTL in 27/5%. Sensitivity/specificity of MRI when compared to surgery was 100/100% for injuries of the AFTL, 64/100% for the FCL, and 33/78% for the PFTL. (orig./MG) [Deutsch] 56 Patienten wurden mit der klinischen Diagnose einer frischen Supinationsverletzung des oberen Sprunggelenkes untersucht. Das Lig. talofibulare ...

1996-03-01

47

Dura thickening adjacent to intracranial tumors on MRI. Histologically correlation; Duraverdickung am Rand intrakranieller, duranaher Raumforderungen in der MRT. Histologische Korrelation  

Energy Technology Data Exchange (ETDEWEB)

Purpose: With intracranial tumors a flat, contrast-enhancing, probably dural structure adjacent to the tumor can occasionally be observed on gadolinium-DTPA enhanced MR images. Therefore we have attempted to evaluate a tumor infiltration of this enthancement on MRI. Material and Methods: This study included 50 patients. 19 patients had a dural thickening at the tumor base (13 meningiomas and 6 metastases), while 31 patients did not (12 meningiomas and 19 metastases). Studies included plane T{sub 2}-weighted spin echo (SE) images as well as T{sub 1}-weighted axial, coronal, or sagittal plains with and without contrast agent. Histopathological examinations, were done on the tumor base adjacent to the dura mater. Results: 7 of 12 meningiomas showed a meningeal thickening on MRI with histopathologically proven tumor infiltration as did also 5 of 6 metastases. But 3 of 12 meningiomas and 15 of 19 metastases without dural thickening at the tumor base also showed tumor invasion into the dura ...

1997-11-01

48

Comparison of contrast-enhanced flash and turbo-flash with conventional spin-echo sequences as a basis for morphologocal MR imaging for planning high-precision radiotherapy of intracranial brain tumors. Comparison of FLASH-, turbo-FLASH and SE-sequences; Morphologische MR-Bildgebung mit T1-gewichteten Sequenzen zur radiotherapeutischen Zielvolumendefinition von intrakraniellen Tumoren. Vergleich von FLASH-, Turbo-FLASH- und SE-Sequenzen  

Energy Technology Data Exchange (ETDEWEB)

Introduction: The goal of this study was to compare contrast-enhanced T1-weighted Flash and Turbo-Flash sequences with conventional spin-echo sequences as a basis for planning high-precision radiotherapy. Methods: A total of 25 consecutive patients with different intracranial tumors and a disrupted blood-brain barrier were studied. T1-weighted Flash, Turbo-Flash and conventional spin-echo images were evaluated after controlled 30-s infusion of 0.1 mmol/kg body weight of Gd-DTPA. The evaluation of the three sequences included the measurement of the signal- and contrast-to-noise ratios, the visual inspection of the tumors and artifacts, and the measurement of tumor size. Results: The signal- and contrast-to-noise ratios were significantly (P<0.05-0.01) lower for Flash and Turbo-Flash than for conventional spin-echo sequences. However, visual inspection of the contrast-enhancing tumors revealed in 23 and 24 of 25 lesions of Flash and Turbo-Flash images, respectively, good or very good ...

1997-03-01

49

TA project 'Elements of a strategy for sustainable development in the energy sector'. Preliminary study; TA-Projekt 'Elemente einer Strategie fuer eine nachhaltige Energieversorgung'. Vorstudie  

Energy Technology Data Exchange (ETDEWEB)

The issue of projecting policies ensuring appropriate energy supply in the future has become more important in Germany after conclusion of the agreement on a long-term nuclear power phase-out. A recent comparative analysis of a selection of scientific studies forecasting the implications of a nuclear power phase-out has shown that there is demand for more studies examining the issue in greater detail, and on the basis of an enlarged scope of research topics. Hence the present study, intended as a preliminary analysis, will investigate the potential, conditions of successful application, conceivable support schemes, and effects of those policy options that in any case, apart from the nuclear power phase-out scenario, are of essential importance in the context of building the proper conditions for sustainable development of Germany's energy sector. The options and strategies examined are: stepping up energy efficiency programmes and incentives, enhancing exploitation of the ...

2000-12-01

50

Quantitative CT assessment of proximal femoral bone density. An experimental study concerning its correlation to breaking load for femoral neck fractures; Quantitative CT des proximalen Femurs. Experimentelle Untersuchungen zur Korrelation mit der Bruchlast bei Schenkelhalsfrakturen  

Energy Technology Data Exchange (ETDEWEB)

Purpose: In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined. Methods: The bone mineral density 41 random proximal human femora was estimated by single-energy quanitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm{sup 3} volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred. Results: Statistical analysis revealed a linear correlation between the trabecular bone density and the fracture load for the greater regions, with the highest value in the ...

1997-12-01

51

Preoperative MR-guided localization of suspicious breast lesions; MR-gesteuerte praeoperative Drahtmarkierung unklarer Mammalaesionen  

Energy Technology Data Exchange (ETDEWEB)

Purpose: Small suspicious breast lesions that are only visible at MR imaging were preoperatively marked with a hook wire under MR-guidance to allow the removal of the lesion with tissue-sparing surgery. Method: In all patients the suspicious lesions were marked preoperatively under MR guidance with a hook wire using a commercially available stereotactic device. Interventions were performed with MR guidance on a 1.0 T and on a 1.5 T system. Results: In 19 patients 22 lesions were localized. One lesion was missed and removed in a second procedure. The mean duration for localization was 66{+-}20 min (range 38-119 min). In two patients two lesions were localized. The mean deviation of the wire tip to the lesion was 2,0{+-}2,6 mm. In this series, 6 of 22 lesions were malignant. The mean diameter of the lesion was 7.6{+-}2.6 mm (range 3-14 mm). Conclusion: Suspicious breast lesions detectable only in MR imaging can be accurately localized with a hook wire preoperatively under MR control to ...

2000-09-01

52

Optimization and testing of a 75 MW temperature combustion chamber for coal gas. Final report; Optimierung und Erprobung einer 75 MW Hochtemperaturbrennkammer fuer den Kohlegaseinsatz. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

Objective: Optimization and testing of a high temperature combustion chamber for burning coal gas and conventional fuels natural gas or fuel oil. Coal gas is not available in such quantity for testing a full scaled combustion chamber. Therefore the design of the combustion chamber is based of experimental results from model tests and numerical solution procedures. Working program: (1) Analytical model for burning coal gas implemented in an existing computational fluid dynamics (CFD) code. (2) Three-dimensional calculations of a full scaled combustion chamber with a CFD code for flows accompanied by combustion and chemical reaction. (3) Improvement of measuring method for determination of flame temperature and concentration. (4) Temperature and concentration profil measuring in a full scaled combustion chamber by operating with natural gas or fuel oil. Results: An analytical model for burning coal gas was implemented in an existing two-dimensional CFD code. The model gave acceptable ...

1994-03-01

53

Excessive copper concentrations in the tap water of households with copper pipes and an assessment of possible health hazards for infants. First results of a study; Gesundheitliche Gefaehrdung ungestillter Saeuglinge durch Kupfer in Haushalten mit kupfernen Trinkwasserleitungen. Erste Ergebnisse einer prospektiven Studie  

Energy Technology Data Exchange (ETDEWEB)

To determined precisely a possible connection between the amount of copper in tap-water and the risk of early childhood liver disease, it was attempted through an epidemiological survey, to determine the extent of excessive concentrations of copper in the tap-water of households with copper pipes. Water samples from 956 households were tested for copper, and the state of health of the infants in these households was documented. Infants who had been fed using water with a copper concentration of 0.8 mg/l or more received a paediatric examination with a blood serum analysis to rule out any liver damage. A copper level greater than 0.8 mg/l was found in only 2% of the households examined. Eight infants were examined by a paediatrician and their serum was analysed. These infants had either been breast-fed to the 12th week or had received more than 200 ml of tap water per day during first 12 months. None of the infants examined showed any signs of liver malfunction. From the results of the ...

2000-04-01

54

Effects of plastic waste injection on the cupola furnace and blast furnace process; Auswirkungen des Einblasens von Kunststoffabfaellen auf den Kupolofen- und Hochofenprozess  

Energy Technology Data Exchange (ETDEWEB)

On account of a raised appearing of plastic waste and shreddered light fraction (SLF) from old car utilization as well as legal handicaps experiments were carried out at the Institute of Ferrous Metallurgy (RWTH Aachen) on a laboratory rig to inject DSD (Duales System Deutschland)-plastic waste and SLF with the destination of a subsequent raw material utilization in the blast furnace and cupola furnace. The experiments on the laboratory rig with DSD plastics could verify that by injection of specific coal/plastic mixtures into the blast furnace the injection rate could be raised by an improvement in the conversion degree and therefore the amount of the inserted reducing agent can be lowered. The injection of SLF without reduction of the inert materials and of the contents on alloying elements and/or tramp elements by extensive preparation has no advantages according to the experiments for the blast furnace process. Pilot experiments on the cupola furnace showed that, assuming a certain ...

1996-01-01

55

The effect of trace elements on the fatigue behaviour of a carbide-hardened Fe-Ni-Cr alloy. Der Effekt von Spurenelementen auf das Zeitstandverhalten einer karbidverfestigten Fe-Ni-Cr-Legierung  

Energy Technology Data Exchange (ETDEWEB)

Fatigue tests were accomplished with a series of specimens doped with trace elements of a hardened Fe-Ni-Cr alloy, cast and hardened with intermetallic phases for determining the influence of these elements on the high temperature strength properties. The results of extensive fatigue tests show that even small contents of Te, Bi, Se, Pb, Tl and Zn considerably influence the life and creep processes especially after longer running periods, when added individually or combinedly. In contrast to this, the fatigue ductility is reduced by trace element additions even with short running periods. The order in which the metallic trace elements influence the fatigue properties nearly correlates with earlier work concerning Ni- and Co-superalloys. (orig.)

1993-01-01

56

Symptom experiences during chemotherapy treatment-With focus on nausea and vomiting  

British Library Electronic Table of Contents (United Kingdom)

ZusammenfassungUbelkeit und Erbrechen stellen zwei Symptome dar, die grundlich untersucht worden sind und bei Krebspatienten haufig auftreten. Die meisten Studien haben sich bislang mit Haufigkeit und Management dieser beiden Symptome befasst. Das Ziel dieser Studie bestand darin, ein besseres Verstandnis dafur zu entwickeln, wie Krebspatienten ihre Symptome erleben-insbesondere Ubelkeit und Erbrechen nach Chemotherapie-und welche Auswirkungen diese Symptome auf den Tagesablauf der Patienten haben. Neun Frauen mit unterschiedlichen Krebsleiden und Chemotherapie Regimes wurden zwecks Chemotherapie stationar aufgenommen und nahmen an der Studie teil. Es wurden halbstrukturierte Interviews einschliesslich einer Inhaltsanalyse in Anlehnung an Kvale durchgefuhrt (Klarung und Entwicklung neuer B...

2006-01-01

57

Studies on biosorption and toxicity of heavy metals in bacteria; Untersuchungen zur Biosorption und zur Toxizitaet von Schwermetallen auf Bakterien  

Energy Technology Data Exchange (ETDEWEB)

Biosorption behaviour of and toxic effects of heavy metals in submersed and immobilised microorganisms was studied in batches and in continuous processes in an airlift-recycle reactor. Nickel, cadmium, and zinc were used as heavy metals. (orig./VHE) [Deutsch] Am Beispiel einer Naphthalin-2-sulfonsaeure-abbauenden Kultur wurde das Biosorptionsverhalten und die toxische Wirkung von Schwermetallen auf submerse und immobilisierte Mikroorganismen im Batch-Ansatz und im kontinuierlichen Betrieb in einem Airlift-Schlaufenreaktor untersucht. Als Schwermetalle wurden Nickel, Cadmium und Zink eingesetzt. (orig./VHE)

1993-09-01

58

Steam turbine blading with variable degree of reaction; Dampfturbinen-Beschaufelungen mit variablem Reaktionsgrad  

Energy Technology Data Exchange (ETDEWEB)

Liberalization and the associated necessity of providing, where possible, inexpensive electrical energy, has intensified still further the demand for higher efficiency steam turbines. Accordingly, continuous efforts are being taken to improve all the flow guiding components of a steam turbine. Special attention is given here to the blading. (orig.) [Deutsch] Die Liberalisierung und die damit verbundene Notwendigkeit, elektrische Energie moeglichst preisguenstig zur Verfuegung zu stellen, hat die Forderung nach hohen Wirkungsgraden von Dampfturbinen weiter verschaerft. Es werden daher kontinuierlich Anstrengungen unternommen, alle stroemungsfuehrenden Teile einer Dampfturbine zu verbessern. Das Hauptaugenmerk gilt dabei der Beschaufelung. (orig.)

1998-05-01

59

Soft factor 'felt comfort'. Room air quality, an important element; Soft-Factor Wohlbefinden. Raumluftqualitaet als wichtige Grundlage  

Energy Technology Data Exchange (ETDEWEB)

Facility management has long been regarded as a cost reduction measure, but it is also a means of raising the financial worth of a building so that landlords can get higher rents or sell the building at a better price. [German] Lange Zeit wurde Facility Management als eine Massnahme zur Kostensenkung angesehen. Heutzutage zeigt sich immer mehr, dass das Facility Management sehr viel umfassender zu verstehen ist: Der Wert eines Gebaeudes bemisst sich nicht allein an einer niedrigen Kostenquote, sondern er soll umfassend Investoren wie Mietern den hoechst moeglichen Nutzen bringen. Nicht allein der kostenguenstige Betrieb ist entscheidend, sondern der Wert des Gebaeudes muss insgesamt gesteigert werden. (orig.)

2002-07-01

60

Re-formation and re-crystallisation behaviour of {gamma}`-free ODS nickel-based alloy PM 1000; Umform- und Rekristallisationsverhalten der {gamma}`-freien ODS Nickel-Basis-Legierung PM 1000  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work was the examination of the coarse grain recrystallisation of the {gamma}-free ODS nickel-based alloy PM 1000 depending on the various parameters due to the processing during heat treatment. After isotropic hot compacting (HIP) of the mechanically alloyed powder, one observes a homogeneous sub-microscopic fine grain structure which can coarsen during high temperature heat treatment, due to sufficiently high driving force from the grain boundary energy via abnormal grain growth to 600 times its size. The setting of the elongated high temperature resistant recrystallisation structure is, however, not connected with this. The dependence of the sucess of re-crystallisation on the re-forming parameters (re-forming temperature and degree of re-forming) was shown by a socalled re-forming card. In order to achieve re-crystallisation to a coarse and aligned grain structure, apart from a certain absolute minimum degree of re-forming, the re-forming must occur within a defined ...

1996-05-01

61

Pathologie und molekulare Pathologie von Lungentumoren  

British Library Electronic Table of Contents (United Kingdom)

Zusammenfassung Das Lungenkarzinom ist eine der h?ufigsten Krebserkrankungen und die h?ufigste Krebstodesursache. Mit der Einf?hrung innovativer Substanzen ist die M?glichkeit einer individualisierten Therapie gegeben, die eine Verbesserung von Prognose und Lebensqualit?t verspricht. Die Wirksamkeit dieser Therapeutika basiert auf spezifischen molekularen Eigenschaften des Lungenkarzinoms und stellt neue Anforderungen an die pathohistologische Diagnostik. Neben dem Histotyp haben sich molekulare Alterationen, insbesondere EGFR-Mutationen, als pr?diktive Marker erwiesen. Die histologische Typisierung umfasst daher nicht nur die Unterscheidung von SCLC und NSCLC, sondern die Subtypisierung der NSCLC unter Einbezug immunhistologischer und molekularer Untersuchungen. Zusammenfassend werden Kri...

2011-01-01

62

New materials for pump bearings prevent damage in tubular type pumps; Neue Pumpenlagerwerkstoffe verhindern Schaeden an Rohrgehaeusepumpen  

Energy Technology Data Exchange (ETDEWEB)

Modern tubular type pumps commonly have lubricated radial bearings which require no compressed water supply and reduce the servicing requirements. Problems that may possibly result from entrained sand in the pumped fluid were solved with the development of ceramic Residur {sup trademark} bearngs in the early eighties. (orig.) [German] In zunehmendem Masse werden Rohrgehaeusepumpen mit foerdermediumgeschmierten Radiallagern ausgestattet, da dies z.B. neben dem Wegfall einer ansonsten notwendigen Druckwasserversorgung auch einen deutlichen reduzierten Wartungsaufwand nach sich zieht. Den Problemen durch eine moegliche Sandbeladung des Foerdermedium wurde bereits durch die Entwicklung der keramischen Residur {sup trademark} -Lager Anfang der 80er Jahre Rechnung getragen. (orig.)

1998-07-01

63

Interventional MR imaging: Clinical results obtained with a 1.5 Tesla system; Interventionelle MR-Tomographie: Klinische Erfahrungen mit einem 1,5 Tesla System  

Energy Technology Data Exchange (ETDEWEB)

The clinical feasibility of using interventional examination techniques was tested with an equipment combining fluoroscopy and MR imaging. This hybrid system showed to be of advantage in a great number of interventional examinations. The 1.5 Tesla magnet proved to be superior to open MR scanning systems in terms of image quality and scanning times. (orig.) [Deutsch] Es wurde die klinische Durchfuehrbarkeit interventioneller Techniken an einem kombinierten Durchleuchtungs- und MR-Arbeitsplatz untersucht. Dieses Hybridsystem erwies sich bei einer Vielzahl interventioneller Eingriffe als vorteilhaft. Der 1,5 Tesla-Magnet ist offenen MR-Systemen hinsichtlich Bildqualitaet und Messzeit ueberlegen. (orig.)

1997-05-01

64

Interdisciplinarity, more than just a word? Findings of a case study on urban water management; Ist die Interdisziplinaritaet mehr als ein Schlagwort? Erkenntnisse aus einer siedlungswasserwirtschaftlichen Fallstudie  

Energy Technology Data Exchange (ETDEWEB)

This is the first interdisciplinary approach to urban water and waste water managment. The author presents the knowledge acquired during the project. [German] Die ganzheitliche Betrachtung der Wasserwirtschaft in urbanen Gebieten ist sowohl in der Forschung als auch in der Praxis neu. Zwischen der Bearbeitung eines Forschungsprojektes und eines Ingenieurprojektes gibt es grundsaetzliche Differenzen, trotzdem sind wir der Meinung, dass es bezueglich der interdisziplinaeren Aspekte und der ganzheitlichen Betrachtung der Wasserwirtschaft sowohl in der Forschung als auch in der Praxis aehnliche Probleme gibt. Aus diesem Grunde wird in dieser Arbeit versucht ueber einige Erfahrungen aus dem interdisziplinaeren und ganzheitlichen Forschungsprojekt zu berichten. (orig.)

2000-07-01

65

Functional MRI of the pharynx in obstructive sleep apnea (OSA) with rapid 2-D flash sequences; Funktionelle MRT des Pharynx bei obstruktiver Schlafapnoe (OSA) mit schnellen 2D-FLASH-Sequenzen  

Energy Technology Data Exchange (ETDEWEB)

Functional imaging of the pharynx used to be the domain of cineradiography, CT and ultrafast CT. The development of modern MRI techniques led to new access to functional disorders of the pharynx. The aim of this study was to implement a new MRI technique to examine oropharyngeal obstructive mechanisms in patients with obstructive sleep apnea (OSA). Sixteen patients suffering from OSA and 6 healthy volunteers were examined on a 1.5 T whole-body imager (`Vision`, Siemens, Erlangen Medical Engineering, Germany) using a circular polarized head coil. Imaging was performed with 2D flash sequences in midsagittal and axial planes. Patients and volunteers were asked to breathe normally through the nose and to simulate snoring and the Mueller maneuver during magnetic resonance imaging (MRI). Prior to MRI, all patients underwent an ear, nose and throat (ENT) examination, functional fiberoptic nasopharyngoscopy and polysomnography. A temporal resolution of 6 images/s and an in-plane resolution of ...

1996-03-01

66

Ecological aspects to the use of pretreated waste in thermal plants; Oekologische Aspekte beim Einsatz aufbereiteter Abfaelle in thermischen Anlagen  

Energy Technology Data Exchange (ETDEWEB)

The present contribution focuses on the input side of individual process techniques. It shows on the basis of example calculations how two parameters describing the incinerable (residual) waste that are of particular importance for unconventional thermal treatment methods, namely ``pollutant load`` and ``calorific value``, can be influenced by a recycling stage and then further by mechanical-biological pretreatment. [Deutsch] Im folgenden soll das Hauptaugenmerk auf die Inputseite zu den einzelnen thermischen Verfahren gelegt werden und anhand einer Beispielrechnung aufgezeigt werden, wie sich die fuer einen Einsatz in nichtkonventionellen thermischen Verfahren besonders wichtigen Parameter des aufbereiteten (Rest)Abfalls `Schadstoffbelastung` und `Heizwert` zunaechst durch eine Verwertung und weiter durch eine mechanisch-biologische Vorbehandlung veraendern. (orig./SR)

1998-09-01

67

Die Behandlung laryngealer Bewegungsst?rungen mit Botulinumtoxinen  

British Library Electronic Table of Contents (United Kingdom)

ZusammenfassungDie Botulinumtoxinbehandlung ist eine etablierte Methode in der Behandlung von spasmodischen Dysphonien. Prinzipiell kann eine Behandlung transkutan zervikal, transoral mit einer gebogenen Spritze unter visueller Kontrolle w?hrend der Laryngoskopie sowie mittels flexibler Endoskope bzw. Videoendoskope mit Arbeitskanal erfolgen. Insbesondere die transkutane Injektion unter Larynx-EMG-Kontrolle (LEMG) ist ein verh?ltnism??ig einfaches Verfahren. Aufgrund der visuellen Kontrolle bei transoral oder flexibel transnasal verabreichtem Botulinumtoxin scheint eine bessere Wirksamkeit zu bestehen. Aus verschiedenen Gr?nden kann dieses Verfahren aber nicht bei allen Patienten verwendet werden. Wir berichten ?ber unsere Erfahrungen mit den verschiedenen Techniken und unsere Erw?gungen i...

2007-01-01

68

MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography; MR-Tomographie in der morphologischen Darstellung der isolierten non-compaction des linksventrikulaeren Myokards (NCVM)  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T{sub 1}-weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness was measured for non-compacted and compacted myocardium and ...

2003-09-01

69

Testing and modification of a simple flow turbine; Messtechnische Untersuchung und Modifikation einer einfachen Durchstroemturbine  

Energy Technology Data Exchange (ETDEWEB)

A study conducted at the IHS had the aim to obtain basic information on whether it is possible to build flow turbines following the free jet principle that are on a par with, or superior to, the conventional design, especially in terms of performance and the efficiency curve. Several inflow contours with a ventilated free jet and a conventional flow turbine were studied. The direct comparison of these variants revealed a slightly enhanced peak load efficiency and a very distinct superiority of the free jet contour during partial load. But the efficiency of all variants failed to attain the values claimed by commercial manufacturers. As compared to the initial contour, peak load efficiency was enhanced by 5 per cent. During partial load, the variants studied showed a distinct superiority of the free jet concept over the contour of conventional flow turbines. (orig.) [Deutsch] Am IHS wurde eine Untersuchung mit dem Ziel durchgefuehrt, grundlegende Aussagen zu gewinnen, ob ...

1997-12-31

70

Saturn technology - high output solar cells for varied use; Saturn-Technologie - Hochleistungssolarzellen fuer einen vielfaeltigen Einsatz  

Energy Technology Data Exchange (ETDEWEB)

The laser grooved buried grid (LGBG) cell was developed at the University of New South Wales, Australia. The enormous advantage of the Saturn technology is the simple formation of a selective emitter via two step diffusion, which is optimised on the surface for the charge carrier generation and under the metal grid for contact formation. The reflection losses due to shading are simultaneously minimised by the installation of the contacts at right angles in the wafer surface. Due to the increased infeed compensation, particularly the compensation covering the costs, the economic importance of the energy yield of a PV plant is growing. Ultimately, it is not just the installed output (KWp) that matters to the customer, but increasingly the specific yield (kWh/kWp). An increased energy yield with optimally matched components with the Saturn technology means high annual compensation, which in turn shortens the amortisation period. [Deutsch] Die LGBG-Zelle wurde an der Universitaet von New ...

1998-12-01

71

Rational imaging strategies in larynx disease; Rationelle bildgebende Strategien bei Kehlkopferkrankungen  

Energy Technology Data Exchange (ETDEWEB)

Clinical information is indispensable for swift and cost-effective clarification of diseases of the larynx. While quality clarification of neurological changes in the area of the posterior cranial fossa and in the course of the vagus nerve as a cause of glottis malfunction is possible with MRI, localized disease of the larynx can more effectively be assessed with low-artifact CT. In the particularly difficult assessment of the post-operative larynx, a recurrence can be diagnosed only after a baseline study has been carried out after the end of therapy. With knowledge of the pretherapeutic findings, the findings immediately post-therapy, and the operation technique used, the optimal CT examination, which can be carried out quickly, will be able to provide more information about recurrence. (orig.) [Deutsch] Zur schnellen und kostenguenstigen Abklaerung von Erkrankungen des Larynx ist die klinische Information unabdingbar: Wenn neurologische Veraenderungen im Bereich der hinteren ...

1998-02-01

72

Production of olefins from recycling polyolefins by means of thermal steam cracking; Olefinerzeugung aus Recycling-Polyolefinen durch thermische Dampfspaltung  

Energy Technology Data Exchange (ETDEWEB)

As one of the largest contractors for the construction of ethylene plants featuring steam cracker furnaces as their core component Linde AG has examined the `real` chemical recycling of polymers in steam cracker furnaces as an alternative to their thermal utilisation. In steam cracker furnaces the feedstock, i.e., hydrocarbons, is broken down to ethylene, propylene, and other valuable products in a steam dilution of approx. 800-870 C. In the ideal case, if polyolefins are used as feedstock, then the initial product which led to the polymers can be fully recycled. In this context a series of experiments was carried out in a laboratory-scale cracker plant. The purpose of this was to demonstrate the technical feasibility and the economic advantage of using recycling polyethylene or polypropylene as feedstock for steam cracker plants. (orig./SR) [Deutsch] Die Linde AG als einer der bedeutendsten Kontraktoren fuer den Bau von Ethylenanlagen, deren Herzstueck die ...

1996-12-31

73

New atomic energy law - international and national developments. Proceedings; Neues Atomenergierecht - internationale und nationale Entwicklungen. Tagungsbericht  

Energy Technology Data Exchange (ETDEWEB)

Two of the working sessions of the meeting were devoted to aspects of international atomic energy law; the international character of the meeting was also reflected by the home countries of the members of the panel discussion concluding the working sessions. There was substantial reason to put emphasis on the international dimension of the topics discussed. In June 1994, the Nuclear Safety Convention had been signed in Vienna by diplomatic representatives of the signatory countries, and this Convention marks a signpost in the history of international atomic energy law. At the time the meeting was held, negotiations for improving the international nuclear lability law, which had been dragging on since 1989, had come to a stalemate. The meeting offered a suitable forum for taking a scientific approach to tackle the complex problems involved in reshaping the law on nuclear safety and nuclear liability. The third working session of the meeting has been discussing topics relating to the ...

1995-12-31

74

Mathematical modelling of ash deposition of dispersed fuels; Mathematische Modellierung des Mineralansatzverhaltens disperser Brennstoffe  

Energy Technology Data Exchange (ETDEWEB)

A numeric method for predicting mineral ash deposition in coal dust furnaces is presented which is based on a bidirectional working time coupling of thermodynamic calculation routines (ChemApp{sup TM}) with the commercial CFD code FLUENT{sup TM}. The deposition characteristics of particles and wall surfaces is assessed on the basis of evaluations of flow simulation parameters and results of thermodynamic calculations for the mineral matter contained in the fuel particles, taking into account the complete energy, momentum and mass exchange history of the ash and the mineral conversion. The models enables calculations of the gaseous release of mineral components (e.g. alkaline substances and chlorine) from ash during combustion and its distribution inside a combustion chamber. The method and model are validated using experimental data. (orig.) [German] In der vorliegenden Arbeit wird ein numerisches Verfahren beschrieben, mit dem die Ansatzbildung in Kohlestaubfeuerungen praediktiv ...

2003-07-01

75

LES study of heat transfer augmentation and wake instabilities of a rotating disk in a planar stream of air  

Energy Technology Data Exchange (ETDEWEB)

Large-eddy-simulations are performed for the heat transfer and the wake flow of a thin rotating disk subjected to an outer parallel passing stream of air. Above a critical value for the angular velocity of the disk, heat transfer augmentation sets on. This is strongly related to a flow instability that leads to a periodic vortex generation at the counter-moving disk side. The resulting phenomena are captured by the classical Landau model. For higher angular velocities the wake becomes fully turbulent, and here the transition to turbulence seems to be very abrupt. In this regime, a periodic vortex generation is observable at the co-moving disk side, too. (orig.) [German] Grobstruktur-Simulationen werden fuer die Waermeuebertragung und die Nachlaufstroemung fuer eine duenne rotierende Scheibe in einem aeusseren parallelen Luftstrom durchgefuehrt. Oberhalb eines kritischen Wertes fuer die Rotationsgeschwindigkeit setzt eine Verstaerkung der Waermeuebertragung ein. Dies ist eng mit ...

2004-02-01

76

Diffusion and perfusion MR imaging in stroke; MR-Diffusion und -Perfusion beim Schlaganfall  

Energy Technology Data Exchange (ETDEWEB)

Magnetic resonance imaging (MRI) in stroke makes it possible to visualize the initial infarct in cases of acute cerebral ischemia. Perfusion MRI serves to determine which tissues are additionally at risk of infarction due to persistent hypoperfusion. MRI also allows those examiners with limited experience to reliably confirm an infarct. The most important differential diagnosis of cerebral ischemia, intracerebral hemorrhage, can likewise be recognized with certainty using MRI. Although diffusion and perfusion MRI only demonstrate the pathophysiology of cerebral ischemia approximately, the method is suited for identifying those patients who would profit from reperfusion therapy. Whether MRI is also appropriate as an aid to reaching a prognosis on the risk of secondary hemorrhage has not yet been resolved. (orig.) [German] Die Schlaganfall-MRT ermoeglicht es, bei akuter zerebraler Ischaemie den bereits initial entstandenen Infarkt darzustellen. Mittels Perfusions-MRT kann erfasst werden, ...

2005-05-01

77

Biosorption of heavy metals under anaerobic conditions. Final report; Biosorption von Schwermetallen unter anaeroben Bedingungen. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

The precipitation of heavy metals as hydroxides is the standard technique for the decontamination of waste water streams polluted by these elements. On the other side, progress in research has been made concerning the biosorption onto dead biomass and bioprecipitation supported by physiologically active bacteria. As the aim of this study, a flexible strategy has been envisaged cleaning a waste water with definite heavy metal load underlying the process mentioned above. Suitable bacteria were enriched and the process was tested in a technical plant. As result, a very high efficiency of heavy metal elimination has been found. The field of application covered by the acquired process is identical with the whole range of the waste water streams polluted by heavy metals. In addition, a second stage may be necessary if there are any further contaminants to be removed. (orig.) [Deutsch] Bei der Reinigung von schwermetallhaltigen Abwaessern ist der derzeitige Stand der Technik gegeben durch die ...

1996-12-31

78

Analysis of FARO spreading experiments  

Energy Technology Data Exchange (ETDEWEB)

Two spreading experiments were performed at the FARO facility with prototypical core melts of a UO{sub 2}/ZrO{sub 2} weight percentage of 80/20. The objective was to obtain data on the spreading at flow rates of about 2 l/s of more than 100 kg prototypic high temperature oxide melt on a dry and wet stainless steel plate. For the second spreading test a shallow water layer of 10 mm was added on the substrate. Solutions for an isothermal spreading with a constant volume flux boundary condition in a sector with an angle {phi} are used to analyse the FARO L-32S experiment and to identify the source of discrepancies between the code results (THEMA, CORFLOW) and the experimental findings. The observed spreading behaviour of both FARO experiments can only be explained if an initial melt temperature below the liquidus temperature, i.e. about 120 K lower than the temperature measured by the UTS sensors is assumed. (orig.) [German] Zwei Ausbreitungsexperimente mit einer ...

2000-08-01

79

Nephron-sparing percutaneous ablation of a 5 cm renal cell carcinoma by superselective embolization and percutaneous RF-ablation  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To report on the nephron-sparing, percutaneous ablation of a large renal cell carcinoma by combined superselective embolization and percutaneous radiofrequency ablation. Materials and Methods: A 5 cm renal cell carcinoma of a 43-year-old drug abusing male with serologically proven HIV, hepatitis B and C infection, who refused surgery, was superselectively embolized using microspheres (size: 500 - 700 {mu}m) and a platinum coil under local anesthesia. Percutaneous radiofrequency ablation using a 7F LeVeen probe (size of expanded probe tip: 40 mm) and a 200 Watt generator was performed one day after transcatheter embolization under general anesthesia. Results: The combined treatment resulted in complete destruction of the tumor without relevant damage of the surrounding healthy renal tissue. The patient was discharged 24 hours after RF ablation. No complications like urinary leaks or fistulas were observed and follow up CT one day and 4 weeks after the radiofrequency ...

2001-11-01

80

MR-based volumetric analysis of small tumor volumes: accuracy of phantom examinations of simulated eye tumors; Evaluierung der MR-Volumetrie kleiner Volumina am Beispiel von Augentumoren mittels Phantomuntersuchungen  

Energy Technology Data Exchange (ETDEWEB)

Purpose: The determination of tumor volume in ocular tumors is very important for the planning and success of radiation therapy. This study uses an animal model to evaluate the accuracy of MR-based volumetry of ocular tumors. Materials and methods: In a total of 25 porcine eyes obtained from the slaughterhouse, ocular tumors were produced by injecting a mixture of hand creme and Gd-DTPA under ophthalmoscopic guidance. The injected volume varied between 0.05 ml and 2.7 ml. The eyes were examined with a 1.5 Tesla scanner and a 4 cm circular surface coil especially developed for ocular MRI. After data transfer to a separate workstation, volumetric analysis was carried out by three independent radiologists using semiautomated software. The determined volume was compared with the injected volume. Results: Of the 25 prepared porcine eyes, 23 were suitable for volumetric analysis. The injection of the mixture of hand creme and GD-DTPA produced two different types of tumors. ...

2003-07-01

81

Lymph node staging in cervical carcinoma: Results of high resolution MRT with phased-array coil; Lymphknotenstaging beim Zervixkarzinom: Ergebnisse der hochaufloesenden Magnetresonanztomographie (MRT) mit einer Phased-Array-Koerperspule  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To determine the diagnostic value of high resolution MR imaging with a circularly polarised (c.p.) body phased-array coil for the staging of pelvic lymph nodes in cervical carcinoma. Material and methods: 42 patients with histologically proven carcinoma of the cervix were studied on a 1.5 T scanner by using a c.p. body phased-array coil. The imaging protocol included T{sub 2}-weighted turbo-spin-echo (TSE) and T{sub 1}-weighted spin-echo sequences pre and post IV application of Gd-DTPA; slice thickness was 5-7 mm and pixel size 0.53 mm{sup 2}. Lymph nodes with a diameter of {>=}8 mm were considered to have metastatic involvement. MR imaging results were compared with histopathologic findings. Results: MR imaging showed enlarged lymph nodes ({>=} 8 mm) in 16 of 18 patients with histologic proof of lymph node metastases (sensitivity 89%). In 22 of 24 cases MR findings were true negative (specificity 92%). Diagnostic accuracy was 91%. Conclusion: High-resolution MR imaging ...

1997-03-01

82

Digital direct magnification mammography with storage phosphor screens. Standardized and image result dependent post-processing parameters; Digitale Vergroesserungsmammographie mit Speicher-Folien-Technik. Standardisierte und befundorientierte Bildverarbeitungsparameter  

Energy Technology Data Exchange (ETDEWEB)

Present day mammography has not been able to make use of the advantages of digital luminescence radiography because of the limited spatial resolution. The recent development of electromagnetic focusing X-ray tube with effective focal spot sizes from 0.04 to 0.12 mm allows radiographic direct magnification with less geometric blur. It is now possible to combine direct magnification mammography with digital luminescence radiography. By combining high quality storage phosphor screens with an HQ-workstation a spatial resolution of 8 lp/mm is possible for 1.7-fold magnification. For 4-fold spot magnification views spatial resolution can be theoretically increased to approx. 20 lp/mm. One important advantage of digital radiography is the possibility of image-postprocessing. This article presents two sets of standard parameters and three sets of image dependent parameters for better imaging of specific lesions, such as microcalcifications. The introduction of the storage phosphor screen ...

1997-05-01

83

Diagnosis of plasmocytomas using magnetic resonance imaging; Diagnostik des Plasmozytoms mit der MRT  

Energy Technology Data Exchange (ETDEWEB)

Background. In multiple myeloma 5 different infiltration patterns can be differentiated: 1. Normal appearance of bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. 'salt-and pepper' pattern with inhomogeneous bone marrow with interposition of fat islands. Methods. For the fast and total acquisition of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique is superior. The focal involvement is clearly demonstrated as areas of high signal intensity on e.g. STIR images. Diffuse involvement can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. MRI is superior to X-ray in focal and diffuse involvement. With ultrafast sequences a 'screening' of the whole red bone marrow as for myeloma infiltration is possible. Prognosis. In prognosis studies diffuse infiltration is inferior to ...

2000-08-01

84

Development of a thermographic measurement process as an alternative to gravimetry in determining Diesel engine particle emission. Final report; Entwicklung eines thermographischen Messverfahrens als Alternative zur Gravimetrie bei der Ermittlung von Dieselpartikel-Emissionen. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

Against the background of more severe limitation of particle emission in all application areas of Diesel engines, it is necessary to monitor the particle emission, but also the chemical composition of the particles. The basis of assessing particle emission is formed by gravimetric determination of the particle concentration from exhaust gas diluted with particle-free ambient air, with a maximum temperature of 52 degrees C at the sampling position. While it is already possible, using the part flow dilution system, to take samples locally, previously the subsequent particle determination and characterisation could only be done in a chemical laboratory. For this reason, the C/S particle measurement process was developed as an alternative to gravimetry, which can be used locally, eg: on ships and which makes it possible to determine the particle mass and composition. This process is based on a thermographic carbon and sulphate determination. Comparative investigations were done both on ...

1994-12-31

85

Behaviour of heat resistant power plant steels undergoing variable long term loading conditions  

Energy Technology Data Exchange (ETDEWEB)

High temperature components of power plants are in many cases subjected to variable loading conditions such as cyclic creep or strain cycling. Therefore the cyclic behaviour of important heat resistant steels has been investigated under stress control and to a smaller extent under strain control. The behaviour under cyclic creep rupture conditions was determined in long term experiments covering a wide range of loading conditions. This behaviour can be described with the modified life fraction rule and a factor concept of relative life for single stage cycles and additionally with a multistep hypothesis for multi-stage cycles. The description can be adapted to estimate the life consumption under service type random conditions. The strain cycling behaviour was investigated in regard to the conditions of the heated surface of large components. To simulate this type of loading and to generate long term creep fatigue data, a service type strain cycle was developed. Anisothermal and ...

2000-01-01

86

Risk of leukaemia following intravenous treatment with {sup 224}Ra - results of a long term follow-up study of ankylosing spondylitis patients; Leukaemierisiko nach intravenoeser {sup 224}Ra-Behandlung - Ergebnisse einer Langzeitstudie an Bechterew-Patienten  

Energy Technology Data Exchange (ETDEWEB)

In an epidemiological study of the somatic late effects risk following incorporation of a short lived {alpha}-emitter, 1473 ankylosing spondylitis patients treated with repeated intravenous injections of {sup 224}Ra in the years 1948 - 75, have been observed in the GSF. The usual therapeutic plan consisted of a total of 10 - 12 injections of 1.036 MBq (28 {mu}Ci) of {sup 224}Ra each, given at weekly intervals; this would result in an cumulative {alpha}-dose of 0.56 - 0.67 Gy to the marrow-free skeleton of a 70-kg-man (standard man). These patients have been followed together with a control group of ankylosing spondylitis patients not treated with radioactive drugs and/or X-rays. Until May 1993 (mean follow-up time 19.9 yr), 595 patients of the exposure group and 722 patients of the control group have died, causes of death have been ascertained for 578, resp. 668 patients. Among others we observed in the exposure group 10 cases of leukaemia (vs. 2.7 - 2.8 cases expected, p < 0.001) ...

1993-12-31

87

Reasons for the power failure in Auckland, New Zealand; Ursachen der Stromunterbrechung in Auckland, Neuseeland  

Energy Technology Data Exchange (ETDEWEB)

On February 20th 1998 Auckland, the biggest city of New Zealand, was nearly paralyzed by an extended power failure. On this day the last of four cables supplying the central business district failed and caused a five weeks lasting blackout. This failure has caused costs of 128.3 Mio NZ Dollar for the affected utility Mercury Energy Ltd. The official ministerial inquiry was published on July 21st 1998 and reproaches the utility in an unusual clear manner. (orig.) [Deutsch] Am 20. Februar 1998 wurde Auckland, die groesste Stadt Neuseelands, von einer folgenschweren Unterbrechung der Stromversorgung nahezu lahmgelegt. An diesem Tag fiel das letzte von vier 110-kV-Kabeln zur Versorgung des Innenstadtbereiches aus und verursachte damit einen 5 Wochen dauernden Stromausfall. Diese Versorgungsunterbrechung hat bisher Kosten in Hoehe von 128,3 Mio NZ Dollar (rd. 115,5 Mio DM) fuer den oertlichen Stromversorger Mercury Energy Limited verursacht. Der am 21. Juli 1998 ...

1998-11-30

88

Pneumokokkenkonjugatimpfstoffe ? Expertenkonsens  

British Library Electronic Table of Contents (United Kingdom)

Zusammenfassung Seit Dezember 2009 ist in Deutschland neben einem 10-valenten (PCV10) auch ein 13-valenter Pneumokokkenkonjugatimpfstoff (PCV13) verf?gbar. Ein Wechsel von PCV7 zu PCV13 ist zu jedem Zeitpunkt einer begonnenen Impfserie problemlos m?glich, von PCV7 zu PCV10 nur bei der Boosterimpfung. F?r alle Kinder mit abgeschlossener vollst?ndiger PCV7- oder -10-Impfserie stellt sich die Frage, ob eine zus?tzliche Impfung mit PCV13 sinnvoll ist. Kinder mit erh?htem Risiko f?r Pneumokokkenerkrankungen gem?? STIKO (St?ndige Impfkommission am Robert?Koch-Institut), die mit PCV7, jedoch nicht mit PPV23 geimpft sind, sollten grunds?tzlich mit PCV13 geimpft werden. Zu diesen Risikokindern sind evtl. auch gesunde, aber bereits im fr?hen Alter in Gemeinschaftseinrichtungen betreute Kinder zu rec...

2011-01-01

89

Plasma immersion ion implantation (PIII) of metals; Plasmaimmersionsionenimplantation metallischer Werkstoffe  

Energy Technology Data Exchange (ETDEWEB)

Plasma Immersion Ion Implantation (PIII) is a new hybrid technology for surface treatment of materials based on the principles of plasma nitriding and ion implantation. The equipment and the operation of the system are introduced. As well as providing an alternate method of ion implantation, it is possible to combine energetic ion bombardment with plasma nitriding. Different metal materials and treatment conditions have been studied. The capability of PIII-treatment to improve the properties of a wide range of metals has been proven. Application for forming tools and their industrial test has been successful. (orig.) [Deutsch] Die Plasmaimmersionsimplantation (PIII) ist eine neue Hybridtechnologie zur Behandlung von Werkstoffoberflaechen und basiert auf den Prinzipien des Plasmanitrierens und der Ionenimplantation. Die Anlagentechnik und die Arbeitsweise werden vorgestellt. Verfahrensspezifische Vorteile entstehen durch die Moeglichkeit, sowohl alternative Ionenimplantationen als auch ...

1995-01-01

90

Optische Uhren. Zeitmessung mit kalten Atomen und Laserlicht  

British Library Electronic Table of Contents (United Kingdom)

Optische Uhren nutzen die Anregung optischer Ubergange in neutralen Atomen oder Ionen. Deren Ubergangsfrequenz liegt bei etwa 1015 Hz, also funf Groenordnungen oberhalb der Gigahertz-Schwingungen heutiger Atomuhren. Das erlaubt eine bis zu tausendmal prazisere Zeitmessung. Fur die Genauigkeit ist es entscheidend, dass der Uhrenubergang eine schmale Linienbreite besitzt und seine Frequenz nicht verschoben wird. Dazu mussen die Atome oder Ionen moglichst ungestort und genau lokalisiert sein. Deshalb basiert ein Uhrentyp auf einem kalten Ion in einer Paul-Falle, ein anderer Uhrentyp arbeitet mit vielen kalten Neutralatomen in optischen Gittern. Der Metrologie sollen optische Uhren zunachst als sekundare Realisierung der Sekunde dienen. Derzeit ermoglichen sie bereits Frequenzmessungen mit 17 ...

2008-01-01

91

Magnetic resonance imaging in acute intractional tuberculosis; Magnetresonanztomographie bei akuter intrakranieller Tuberkulose  

Energy Technology Data Exchange (ETDEWEB)

We reported three cases of acute intracranial tuberculosis including miliary tuberculosis, basal meningitis, tuberculomas and neuritis of cranial nerves. All patients had native and contrast enhanced CT and MRI scans. MRI revealed more granulomas and a better imaging contrast in the detection of basal meningitis. Neuritis was diagnosed only with the MRI. MRI scans should be prefered as the imaging procedure in clinically presumed intracranial tuberculosis. (orig.) [Deutsch] Die Befunde von drei Patienten mit intrakranieller Tuberkulose (intrakranielle Miliartuberkulose, Meningitis tuberculosa, Neuritis und Tuberkulome) in der Magnetresonanztomographie (MRT) wurden mit der Computertomographie (CT) verglichen. Sowohl die MRT als auch die CT wurden nativ und nach Kontrastmittelgabe durchgefuehrt. Die MRT zeigte sich im Nachweis von Granulomen insbesondere im Bereich des Hirnstamms ueberlegen. Ebenso wurde ein hoeherer Bildkontrast bei der Darstellung der Meningitis beobachtet. Eine ...

1994-12-31

92

Investigation on corrosion resistance of nitrided Cr-Mn steels in chloride nitric acid; Korrosionsbestaendigkeit von stickstoffhaltigen Cr-Mn-Staehlen in Salpetersaeure mit Chlorionengehalt  

Energy Technology Data Exchange (ETDEWEB)

The austenitic nitrided Cr-Mn steels CrMnN 1812, CrMnNMo 1714 and CrNiTi 1810 has been investigated in chloride nitric acid at temperature 20-60 C. The Potentials of pitting nucleation and the time for pitting initiation has been determinate by the hronoamperometric method. It was established that alloying only with nitrogen is not sufficient procedure for obtaining of resistive to localised corrosion steel structure. Of importance for the resistance to localised corrosion of Cr-Mn steels is alloying with molybdenum. (orig.) [Deutsch] Die austenitischen stickstoffhaltigen Cr-Mn Staehle CrMnN 1812, CrMnNMo 1714 und der klassische CrNiTi 1810 wurden in chloridhaltigen Salpetersaeureloesungen im Temperaturbereich 20-60 C untersucht. Durch die hronoamperometrische Methode wurden die Potentiale der Lochfrassbildung und die Zeit zur Initiierung der Lochfrasskorrosion bestimmt. Man stellte fest, dass das Legieren der Staehle nur mit Stickstoff eine nicht genuegende Massnahme zum Erreichen ...

1997-12-01

93

Investigation of the failure rate of hydraulic dashpots; Untersuchung der Ausfallrate an hydraulischen Stossbremsen  

Energy Technology Data Exchange (ETDEWEB)

The failure rate of dashpots has been determined on the basis of the results of annually recurring function tests on hydraulic dashpots, in order to determine the effects of longer test cycles on the safety of systems GKN I and GKN II. The use of a calculation method made it possible to establish the number of defective dashpots in the system as a whole. A subsequent investigation illustrated the way in which this figure changes when the test interval is increased from four to ten years, and the effects of this on system safety. (orig.) [Deutsch] Zur Ermittlung der Auswirkungen verlaengerter Pruefzyklen auf die Sicherheit der Anlagen GKN I und GKN II wurde, basierend auf Ergebnisse der jaehrlichen Funktionspruefung an hydraulischen Stossbremsen, die Fehlerrate der Stossbremsen bestimmt. Mit Hilfe eines Berechnungsverfahrens konnte die Anzahl maengelbehafteter Stossbremsen in der Gesamtanlage bestimmt werden. Eine anschliessende Untersuchung zeigte, wie sich dieser Wert bei ...

1997-08-01

94

International symposium: concepts for the treatment of wastewater in the rural areas of Europe. Proceedings; Internationales Symposium: Konzepte zur Abwasserbehandlung im laendlichen Raum Europas. Tagungsband  

Energy Technology Data Exchange (ETDEWEB)

In the first part of the symposium, experts reviewed the state of the art of decentralized waste water treatment in Europe. In the second part, exemplary solutions in Poland and the Czech Republic were presented. The final part was dedicated to future concepts and strategies. [German] Im Herbst letzten Jahres hat die Kommunale Umwelt-AktioN U.A.N. in einer Abfolge von drei Abwasserfachsymposien Expertenrunden zum Austausch ueber den aktuellen Stand des Wissens zum Thema dezentrale Abwasserbehandlung veranstaltet. Mit dem Internationalen Symposium 'Konzepte zur Abwasserbehandlung im laendlichen Raum Europas' in Celle hat das Projekt der U.A.N. seinen Abschluss gefunden. Der Konzeption des Projektes entsprechend haben im 1. Teil des Symposiums Experten ueber den Stand der Entwicklung auf dem Sektor der dezentralen Abwasserbehandlung in Deutschland berichtet. Im 2. Teil unserer Fachtagung wurden europaeische Beispiele fuer dezentrale Loesungen aus ...

2000-07-01

95

Injection of recyclable byproducts into a cupola furnace via natural gas/O{sub 2} burners; Einblasen von wiederverwertbaren Reststoffen ueber Erdgas/O{sub 2}-Brenner in einen Kupolofen  

Energy Technology Data Exchange (ETDEWEB)

Disposal of fine-particled byproducts via injection into a capola furnace using natural gas/O{sub 2} burners is a cost-efficient alternative to landfill dumping. Tests conducted in a foundry demonstrated that dusts collected there can be injected without detriment to melt-down rate and iron quality. The replacement of FeSi pellets with FeSi dust in addition reduced the slag content, while injection of coal dust permitted a decrease in coke consumption. (orig.) [Deutsch] Die Entsorgung von feinkoernigen Reststoffen durch Einblasen in einen Kupolofen ueber Erdgas/O{sub 2}-Brenner ist eine wirtschaftliche Alternative zur Deponierung. Anhand von Versuchen in einer Giesserei konnte aufgezeigt werden, dass hier anfallende Staeube ohne nachteilige Auswirkungen auf Schmelzleistung und Eisenqualitaet einzublasen sind. Die Substitution von FeSi-Formlingen durch FeSi-Staub brachte zudem eine Reduzierung des Schlackeanteils und das Einblasen von Kohlenstaub eine Verminderung ...

1997-07-01

96

High performance materials and precious substances made out off renewable substances, specially animal substances. Final report; Hochleistungswerkstoffe und -wertstoffe aus nachwachsenden Rohstoffen, insbesondere aus tierischen Substanzen. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

Basic research in relation to a complete utilisation of animal substances as an alternative to a thermal disposal was done. The composition of different kinds of bones were investigated as well as their amounts which are available. Conventional utilisation was opposed to the innovative utilisation. Technologies will be selected which should be developed, because they have the chance in the case of a fast industrial realisation to get a good profit. There is a global requirement for the technologies which are developed and their products which can be produced with this. The raw material basis is available in the necessary scale in nearly all countries. (orig.) [German] Grundlegende Untersuchungen zur ganzheitlichen Verwertung von tierischen Substanzen als Alternative zur thermischen Entsorgung wurden durchgefuehrt. Es wurde die Zusammensetzung der verschiedenen Knochenarten und ihr Aufkommen untersucht. Die konventionelle wurde der innovativen Verwertung gegenuebergestellt. Es werden ...

2003-05-08

97

Gas turbines in cement plants; Erfahrungen aus dem Einsatz von Gasturbinen in einem Zementwerk  

Energy Technology Data Exchange (ETDEWEB)

Burner nozzles were often redesigned in order to improve flow design and manufacturing quality. Maintenance intervals, however, are not satisfactory for the operators of such plants. There is no definitive answer as to whether upgraded design allows to lengthen these intervals or whether additional measures are required. Gas turbines may break down for a large number of reasons. This article shows that many of the causes of operational failure and damage are preventable. Damage management will be successful if manufacturers, operators and independent institutions work together.(orig.) [German] Es wurden in der Vergangenheit mehrfach Veraenderungen an den Brennerduesen vorgenommen. Dabei wurden Verbesserungen in der stroemungstechnischen Auslegung und der Fertigungsqualitaet erzielt. Die derzeit noch gueltigen Wartungsintervalle sind fuer den Betreiber unbefriedigend. Inwieweit diese Intervalle mit der modifizierten Ausruestung verlaengert werden koennen oder ob weitere Massnahmen ...

1998-07-01

98

Environmental risk assessment. A method for determination and evaluation of the risks of harmful changes in air, water and soils due to hazardous substances which are handled in technical facilities - aspects which are relevant to the Environmental Liabilities Law. Die Beurteilung von Umweltrisiken. Eine Methode zur Ermittlung und Bewertung der Risiken einer schaedlichen Veraenderung der Umweltmedien durch umweltgefaehrdende Stoffe in technischen Anlagen unter dem Aspekt des Umwelthaftungsgesetzes  

Energy Technology Data Exchange (ETDEWEB)

The criterion the study is based on in evaluating environmental risks is the possibility of harmful changes in air, water and soils rather than the harmful environmental impacts these changes are caused by. The two significant criteria, i.e. the evaluated environmental hazards potentials or 'value parameters', and the evaluated damage-to-the-environment probabilities or 'safety parameters', reveal the respective environmental risks or 'risk factors'. These risk factors are classified by 23 environmental risk parameters for differentiation between low-risk and high-aid for pollution abatement measures provided that one fixes acceptance limits for the environmental parameters. As a rule the environmental risks of technical facilities which handle hazardous materials can be evaluated appropriately and the results can be compared. (orig./HSCH).

1992-02-07

99

Energy report Frankfurt am Main 1992; Stadt Frankfurt am Main. Energiebericht 1992  

Energy Technology Data Exchange (ETDEWEB)

By joining the `climate association of European cities`, Frankfurt has agreed to reduce its CO{sub 2}-emissions by 50% by the year 2010. The so-called `climate offense 1991` was the first regulatory paper to be set up by a community to reach this goal over a long term. This report now represents the present level of the project. Main points are the development of houses with low entropy, the retrofitting of heating systems, water saving measures and energy management. (BWI) [Deutsch] Durch den Beitritt zum `Klima-Buendnis der Europaeischen Staedte` hat sich die Stadt Frankfurt/M. verpflichtet, die CO{sub 2}-Emissionen bis zum Jahr 2010 um 50% zu senken. Mit der sog. `Klimaoffensive 1991` wurde dann erstmals von einer Kommune in Deutschland ein detailliertes Regelwerk aufgestellt, um dieses Ziel langfristig erreichen zu koennen. Der vorliegende Bericht stellt den aktuellen Stand des Projektes dar. Kernpunkte sind die Entwicklung von Niedrigentropiehaeusern, die ...

1993-12-31

100

Development of a new NiCrMo steel for welded steam turbine shafts; Entwicklung eines neuen NiCrMo-Stahles fuer geschweisste Dampfturbinenwellen  

Energy Technology Data Exchange (ETDEWEB)

A new material has been developed for welded low-pressure shafts in steam turbines. Nine test welds were examined in order to confirm the chemical analysis. A shaft disc with an optimized composition was produced and destructively tested. The new material demonstrates, both in a total forging and also in a joint weld examined, excellent strength and toughness characteristics as well as excellent resistance to corrosion. Accordingly, all the requirements for welded low-pressure shafts in steam turbines are fulfilled. (orig.) [Deutsch] Fuer geschweisste Niederdruckwellen in Dampfturbinen wurde ein neuer Werkstoff entwickelt. Zur Festlegung der chemischen Analyse wurden 9 Versuchsschmelzen untersucht. Mit optimierter Zusammensetzung wurde eine Wellenscheibe hergestellt und zerstoerend untersucht. Der neue Werkstoff zeigt sowohl im gesamten Schmiedestueck als auch in einer untersuchten Verbindungsschweissung gute Festigkeits- und Zaehigkeitseigenschaften sowie gute ...

1997-06-01

101

Cost reduced inspection concept of PE/XLPE medium voltage cables; Kostensparende Zustandsanalyse an PE-/VPE-isolierten Mittelspannungskabeln  

Energy Technology Data Exchange (ETDEWEB)

The microelectronic cable diagnosis is a substantial tool to determine destruction free the residual strength and the lifetime of laid PE/XLPE medium voltage cables. Fundamentals of the ageing diagnosis and a cost reduced inspection concept are the `Isothermal-Relaxation-Current` Analysis and the Neuro-Fuzzy evaluation software. These new tools are able to determine the ageing status of the investigated cable without any references. The authors also show that the test breakdown during the assessment of the ageing status of criterial systems can be reduced by this approach. The cable diagnosis equipment KDA is also useful for the steering of investment as well as for preventive maintenance. (orig.) [Deutsch] Die zerstoerungsfreie dielektrische Kabeldiagnostik kann heute einen wesentlichen Beitrag zur Bestimmung der Restfestigkeit und der Restlebensdauer eines PE/VPE-isolierten Mittelspannungskabels leisten. Basis der Alterungsdiagnose und des Konzeptes zur kostensparenden Pruefung ist ...

1997-12-15

102

Construction and modernization of small hydroelectric installations with funding by programmes of the EU. Abstract; Neubau und Modernisierung von Kleinwasserkraftanlagen durch Foerderprogramme der E.U.. Kurzfassung  

Energy Technology Data Exchange (ETDEWEB)

The report gives a brief introduction into the EU grant programmes since 1984 and explains the philosophy behind them. The current situation regarding grant opportunities for the construction and modernization of small hydroelectric installations is outlined. Hints are given with a view to grant applications. A selection of small hydro power stations supported by grants (since 1984) are described with their economic and technical features. (orig.) [Deutsch] In diesem Beitrag wird eine kurze Einfuehrung in die EU-Foerderprogramme seit 1984 und Erlaeuterungen zu der Programmphilosophie gegeben. Die derzeitige Situation bezueglich der Foerderung von Kleinwasserkraftanlagen fuer Neubauten und Modernisierungsmassnahmen wird dargestellt. Es werden Hinweise zur Stellung eines Foerderantrags beschrieben. Abschliessend erfolgt die Vorstellung einer Auswahl von gefoerderten Kleinwasserkraftanlagen (seit 1984) mit den wirtschaftlichen und technischen Besonderheiten. (orig.)

1997-12-31

103

Childhood cancer in the surroundings of German nuclear power plants: report of an ongoing epidemiological study; Krebs bei Kindern in der Umgebung von Kernkraftwerken: Bericht zu einer laufenden epidemiologischen Studie  

Energy Technology Data Exchange (ETDEWEB)

Epidemiological studies could not show an association between ionising radiation of nuclear power stations in routine operation and the incidence of childhood cancer, yet. The following report presents a case control study conducted by the German Childhood Cancer Registry since autumn 2003. All children in the study region, who were diagnosed with cancer between 1980 and 2003 at an age below five are included. In the first part of the study we investigate whether children with cancer (cases) lived closer to the respective nuclear power stations compared to random children without cancer (controls). In the second part, for a subgroup of cases and controls we conduct computer assisted telephone interviews regarding confounders possibly associated with the exposure of ionising radiation and childhood cancer. Results are expected by the end of 2006. (orig.)

2006-07-01

104

Calculation of ventilation efficiency and of load situations for load-relieving air conduction systems; Berechnung der Lueftungseffektivitaet und der Belastungssituation fuer lastmindernde Luftfuehrungen  

Energy Technology Data Exchange (ETDEWEB)

Zone modeling permits taking account of the effect of load-relieving air conduction systems in the planning of HVAC plants. Although this only supplies average values for the degree of load and height of the fresh air layer rather than a detailed description of concentration and temperature distributions in the room, it is quite sufficient for the planning of load-relieving air conduction systems. Moreover, the cost of zone modeling in the planning of HVAC plants remains within reasonable limits. Upscale planning, instruments can thus be reserved for more exacting problems. (orig.) [Deutsch] Zonenmodelle erlauben die Wirkung lastmindernder Luftfuehrungen bei der Planung von RLT-Anlagen zu beruecksichtigen. Sie liefern zwar nur Mittelwerte fuer den Belastungsgrad und die Hoehe der Zuluftschicht und keine detaillierte Konzentrations- und Temperaturverteilungen im Raum. Diese Werte reichen jedoch fuer die Planung lastmindernder Luftfuehrungskonzepte aus. Zudem ist der Aufwand fuer den ...

1994-12-31

105

Atlas and toolbook of MR mammography; Lehratlas der MR-Mammographie  

Energy Technology Data Exchange (ETDEWEB)

This richly illustrated toolbook and atlas contains information on all aspects of nmr diagnostic imaging of benign or malignant neoplasms of female and male mammary glands. It offers pinpointed guidance and insight for vocational training and continuing training of radiology assistants, students and medical radiologists. (orig./AJ) [German] Die MRT als hochaufloesendes und schaedigungsfreies Diagnostikum gewinnt gerade in der emotional stark besetzten Mammadiagnostik zunehmend an Bedeutung. Dennoch beherrschen nur wenige Zentren im deutschsprachigen Raum diese Technik, die - eine hohe Reproduzierbarkeit bei fehlender Belastung fuer die Patientin bietet, - invasive Karzinome bereits ab einer Groesse von 5 mm mit hoher Zuverlaessigkeit ausschliessen kann und - gerade bei widerspruechlichen Befunden zwischen klinischer Untersuchung, Roentgenmammographie und perkutaner Biopsie eine wesentliche Entscheidungshilfe bieten kann. Aus einem der fuehrenden Zentren in der ...

2000-07-01

106

A micromachined high pressure stable mass flow sensor for common-rail injection systems; Ein mikromechanisch gefertigter hochdruckstabiler Massenflusssensor fuer Common-Rail(CR)-Einspritzsysteme  

Energy Technology Data Exchange (ETDEWEB)

We report for the first time about a micromachined mass flow sensor directly integrated between the double guidance and the needle seat into the body of a Common Rail (CR) injection nozzle. The thermal measurement principle was chosen because gaseous as well as liquid mass flows can be determined fast and precisely. Additionally, with glass-ceramic materials fabricated in a low cost batch process, a high temperature and especially pressure stable substrate can be used. The flow sensitive thin film is realized by an e-beam evaporated 110 nm thick molybdenum (Mo) layer. The latter is electrically characterized by the resistivity of {rho} = 8.2 x 10{sup -7} {omega} m ({+-}2%) at room temperature as well as by the first {alpha}=4.5 x 10{sup -4} K{sup -1} ({+-}5%) and second {beta}=3.0 x 10{sup -6} K{sup -2} ({+-}12%) temperature coefficients of resistance up to 300 C. The static temperature field at and around the thin film sensor on the glass-ceramic substrate is investigated with an IR ...

2001-05-01

107

The zinc/air battery test of the Deutsche Post AG - first results from practice; Der Zink/Luft-Batterie-Test der Deutschen Post AG - erste Ergebnisse aus der Praxis  

Energy Technology Data Exchange (ETDEWEB)

The Deutsche Post AG is a transport company that with approximately 55,000 vehicles owns one of the biggest fleets in Europe. Being aware of its responsibility in the field of environmental policy it is looking for an alternative solution of an environmentally friendly vehicle drive system that also takes into account economic efficiency. Extensive investigations have led to a new energy storage based on the zinc-air energy system that has been developed and manufactured by the Israeli Company Electric Fuel Ltd. First tests showed an extraordinarily high capacity potential, drive values and ranges, which had been considered as impossible until that point of time. After these tests the Deutsche Post AG decided together with other well-known partners at home and abroad to carry out a territorial test with the zinc-air energy system in order to obtain insight into the day-to-day capability, economic efficiency, environmental friendliness under real driving conditions and into the required ...

1997-07-01

108

TEM-investigations of the effect of iron content on the precipitation behaviour of NiMo28 type alloys; TEM-Untersuchungen zum Einfluss des Eisengehaltes auf das Ausscheidungsverhalten von Legierungen des Typs NiMo28  

Energy Technology Data Exchange (ETDEWEB)

Normally, the alloy NiMo28 is used in the solution annealed and quenched condition in which it has a face centred cubic matrix structure. The matrix of the material is supersaturated with molybdenum and, at temperatures above 800 C, has a tendency to form intermetallic precipitates such as the Ni{sub 4}Mo-ordered phase leading to the embrittlement of the NiMo28-ordered phase leading to the embrittlement of the NiMo28 alloy during hot working. For this reason, the aim of these investigations was to optimise the alloy by reducing its tendency to embrittle. The TEM-analyses carried out served to investigate the precipitation of the material as a function of its iron content after ageing at 700 C. The change in hardness and in the lattice constants of the NiMo28-specimens with iron content were also determined. To improve the hot working properties of this material it is recommended that the iron content be kept to about 3.2 mass % in order to reduce the tendency of the alloy to ...

1996-07-01

109

Supervision of construction, quality assurance, operating experience in the new heating power station II; Bauueberwachung, Qualitaetssicherung, Betriebserfahrungen mit dem neuen Heizkraftwerk II  

Energy Technology Data Exchange (ETDEWEB)

After 3 years of construction the trial run of the heating power station HKW 2 ended in November 1997 on time. No extraordinary damage occured during construction, assembly or commissioning. The plant has been operating according to schedule since November 1997. A brief inspection carried out in the summer of 1998 in order to assess warranty claims showed no damage to any part except one valve. Experience shows that all aforementioned activities were necessary. The paper reports about success and negative experience. Certification according to DIN EN ISO 9000ff., however, affords to guarantee of high-quality construction. Builders of such plants therefore need to set up their own quality assurance centre and ensure its technical competence. If necessary,additional experts should be called in.Quality assurance costs for HKW 2 came to about 0.5-0.6 percent of total costs. In view of the success and long life of this investment these expenses are more than justified. (orig.) [German] Nach ...

1998-07-01

110

Stepped reforming - a new method for recovering energy and hydrogen from biogenic residues; Die Gestufte Reformierung - ein neues Verfahren zur Gewinnung von Energie und Wasserstoff aus biogenen Reststoffen  

Energy Technology Data Exchange (ETDEWEB)

DMT has developed what is called the stepped reforming process. This is an allothermal gasification process which uses hydrogen for a gasification medium. First the biomass is pyrolised by means of a heat transfer material. The escaping gaseous and condensable constituents are hydrogenated, heated in a reforming stage and are made to react to a hydrogen-rich product gas by means of homogeneous gasification. The heat required for this is provided by burning the pyrolysis coke. This makes it possible to dispense with process stages that would involve gasification of solid material and hence require higher pressure levels. The present process also works at ambient pressure. Moreover, stepped reforming promises a number of additional advantages: low-tar product gas containing 60% hydrogen, high cold gas efficiency, no wastewater arisings, robust operating behaviour. This paper outlines the basic ideas that led to the development of stepped reforming process and describes its diverse ...

2000-07-01

111

Staging of osteochondritis dissecans of the knee and ankle with MRI. Comparison with conventional radiography and arthroscopy; Die Stadienbestimmung der Osteochondrosis dissecans am Knie- und Sprunggelenk mit der MRT. Vergleich mit konventioneller Radiologie und Arthroskopie  

Energy Technology Data Exchange (ETDEWEB)

A prospective study was performed on 50 patients suffering from osteochondritis dissecans of the knee and ankle to define criteria for stability and fixation of osteochondral lesions. Morphological parameters in MRI (size, fragmentation, cartilage, interface) and conventional radiology (separation, fragmentation) were registered and compared with arthroscopical staging. MRI staging based on different types of interfaces was demonstrated on T{sub 1}- and T{sub 2}-weighted images. MRI could correctly predict a Grade 1 lesion in 50%, a Grade 2 lesion in 90%, a Grade 3 lesion on 0%, and a Grade 4 lesion in 79%. Stable lesions were differentiated from unstable lesions in 90%. Radiographic findings corresponded with arthroscopic staging in only 56% of the cases because fibrotic connection may guarantee stability in case of bony separation. (orig./MG) [Deutsch] In einer prospektiven Studie an 50 Patienten mit einer Osteochondrosis dissecans (OD) des ...

1995-07-01

112

Specifications for dumping of residues from mechanical-biological waste treament facilities; Anforderungen an die Ablagerung von MBA-Abfaellen  

Energy Technology Data Exchange (ETDEWEB)

For purposes of assessing the dumpability of wastes, Article 1 - Ordinance on the Environmentally Responsible Landfilling of Household Wastes (AbfAblV) - of the Ordinance on the Environmentally Responsible Landfilling of Household Wastes and Biological Waste Treatment Plants defines classificaton criteria for biologically and mechanically treated wastes destined for landfilling. The practical experiences that have been gathered with these classification criteria and values were evaluated in a questionnaire-based survey. This was done in particular for the purpose of verifying and validating proposals on the methodology of respiration and fermentation tests. A general finding has been that the application and implementation of the regulations of the AbfAblV is fraught with difficulties. This is evident for one thing in the frequency of analyses and for another in the difficulty of complying with the limit values of the classification criteria. The authors are in support of demands that ...

2001-07-01

113

Results of measures improving the efficiency in steam turbines of RWE Energie AG; Ergebnis der wirkungsgradverbessernden Massnahmen an Dampfturbinen der RWE Energie AG  

Energy Technology Data Exchange (ETDEWEB)

One part of the RWE measure catalogue in order to guarantee an environmental friendly and competitive electric power generation based on brown coal is to carry out measures improving the efficiency at existing steam turbines in RWE brown coal power plants. Since 1993 a total of 21 steam turbines with a gross capacity of 7,100 MW or net capacity of 6540 MW - this corresponds to approximately 70 % of the installed RWE brown coal power plant capacity - have been improved with an investment of approximately DM 500 million. The net block efficiency has been increased by 1.3 % on average. The planned net capacity increase of approximately 250 MW is still going to be achieved taking into account the pending enhancements. Nuclear power plant turbines have been successfully improved in the same way. Apart from the described retrofit programme measures to improve efficiency are carried out at further steam turbines of brown coal power plants. In the frame of this talk the measures taken are ...

1999-12-01

114

Primary malignant lymphoma of the brain; Primaere maligne Lymphome des Gehirns  

Energy Technology Data Exchange (ETDEWEB)

Primary malignant lymphoma of the brain is a disease of unknown etiology, which is increasing in incidence and has an unfavorable prognosis. Despite the lack of specific changes on CT or MRI in most cases, these procedures may typically facilitate the diagnosis: A focal-enhancing mass with subependymal spread on CT or MRI and hyperattenuation on nonenhanced CT are the most reliable features in the diagnosis of primary malignant lymphoma of the brain. Peritumoral edema and mass effect are usually not prominent features. On unenhanced CT scans they usually appear homogeneously isodense to mildly hyperdense relative to the gray matter. On MRI these tumors are slightly hypointense on T1-weighted images and slightly hpyerintense on PD- and T2-weighted images relative to the gray matter. On CT and MRI enhancement is usually homogeneous. Contrast-enhanced MRI, with its multiplanar capability, lack of bone-induced artifacts, and high-contrast resolution, is likely to reveal subependymal spread ...

1997-01-01

115

Magnetic resonance imaging in the evaluation of pneumonia; Nachweis von pneumonischen Infiltraten mit der MRT  

Energy Technology Data Exchange (ETDEWEB)

Magnetic resonance imaging (MRI) of the lung is challenging because of substantial drawbacks. However, lung pathologies that are associated with increased attenuation values in CT enhance visualization in MRI: proton density is increased and tissue-air interfaces, resulting in susceptibility artifacts, are reduced in pneumonia, pneumonitis, edema, and carcinoma. On the other hand, many lung diseases result in shortness of breath, so that patients cannot hold their breath for long periods. Therefore, fast imaging techniques are required which should also allow for high spatial resolution so that small lesions can be detected. Calcifications and air pockets within lesions are not readily recognized with MRI. Thin section CT is standard for the diagnosis of pneumonia. With parallel imaging techniques, MRI examination of the lungs can be performed with short periods of breath holding, which allow for sub-centimeter resolution in the z-axis. Especially for follow-up examinations in ...

2006-04-15

116

MRT of the abdomen in combination with enteroclysis in Crohn disease with oral and intravenous Gd-DTPA; MRT des Abdomens in Kombination mit der Enteroklyse bei Morbus Crohn unter Verwendung von oralem und intravenoesem Gd-DTPA  

Energy Technology Data Exchange (ETDEWEB)

60 patients between 17 and 72 years of age were investigated. First, an enteroclysis was performed in typical manner. The applicated methylcellulosis was blended with positive oral MR contrast media (Magnevist oral, Schering). After enteroclysis, MRI of the abdomen was performed using T1- and T2-weighted breathhold sequences (Flash 2D pre- and postcontrast and TSE) in axial and coronal planes. The length of the affected bowel and the stenosis seen with enteroclysis correlated well with the visible thickening of the small bowel wall and the stenosis seen in MRI. Using MRI, additional findings could be obtained in 28 patients, such as fistulas, abscesses or a hydronephrosis, or a better assessment of the stenosis was possible with MRI, because of the avoidance of overshadowing of the affected bowel loop with MRI. A brilliant MR-tomographic imaging of the small bowel is possible under the condition, that the small bowel contrast is optimal. The main prerequisite is a large filling volume ...

1998-01-01

117

Local ablading therapy methods in case of liver metastases of colorectal carcinoma; Lokal abladierende Therapieverfahren bei Lebermetastasen kolorektaler Karzinome  

Energy Technology Data Exchange (ETDEWEB)

Clinical studies have proved the effectiveness of local ablading methods in pations with non-resectable liver metastases of a colorectal carcinoma. RF ablation and LITT are a potentially curative therapy option and an alternative to systemic chemotherapy; the latter is carried out primarily for reducing tumour size with the goal of secondary resectability. The number of R0-sesectable metastases can be enhanced by a combined therapy of surgery and local ablading methods, e.g. by preoperative, intraoperative or postoperative ablasion of further non-resectable tumours during surgery. Systemic chemotherapy combined with surgery as an adjuvant method is not recommended unless in cases of non-abladable tumour recidivation. Currently, systemic chemotherapy is used as a neo-adjuvant therapy for tumour size reduction with the goal of secondary resectability or, in case of inoperability, local ablation. (orig.) [German] Abladierende Verfahren. Klinische Studien belegen die Effektivitaet der ...

2003-03-01

118

International nuclear liability as an element of nuclear safety; Internationales Atomhaftungsrecht als Element der nuklearen Sicherheit  

Energy Technology Data Exchange (ETDEWEB)

The main objective of nuclear liability law is the compensation of victims of a possible nuclear incident. However, an adequate nuclear liability law is just as important for nuclear industry, in particular the supply industry - including suppliers of know-how and consultants. Without such a law, the liability risk would be incalculable and industry would not be ready to supply to nuclear installations or nuclear activities. This applies especially to programmes which aim at improving nuclear safety in Eastern Europe. Key elements are the exclusive concentration of liability onto the operator of a nuclear installation (channelling of liability) and the channelling of lawsuits onto one single competent court in one single country. There are recent examples: The negotiations on the management of nuclear waste, including submarines, in Northern Russia and the negotiations within the framework of the East Asian project of the Korean Peninsula Energy Development Organization (KEDO), ...

2002-09-01

119

Formation of damage symptoms to assess the safety margin of components in the high temperature range; Die Entwicklung von Schaedigungsmerkmalen zur Beurteilung der Sicherheitsspanne von Bauteilen im Hochtemperaturbereich  

Energy Technology Data Exchange (ETDEWEB)

Surface structure analysis, i.e. metallographic analysis of component surfaces with the aid of replicas, is an established method of component monitoring and the only reliable non-destructive method for detecting and analyzing beginning creep damage in the form of creep pores. Creep pore development provides a basis for component condition analysis. It must be noted, however, that the modern martensitic 9-12 % Cr steels - like the established steels 10CrMo9-10 (P22) und X20CrMoV12-1 - have comparatively high creep fracture deformation rates in fatigue tests. This raises the question if these steels can be judged on the basis of data for established steels. The results so far suggest that even with low pore densities (single pores), a higher degree of damage and a shorter time until failure must be assumed. [German] Eine bewaehrte Methode der Bauteilueberwachung stellt die Oberflaechengefuegeuntersuchung, d. h. die metallografische Untersuchung der Bauteiloberflaeche mit Hilfe von ...

2005-07-01

120

FLUTAN input specifications  

Energy Technology Data Exchange (ETDEWEB)

FLUTAN is a highly vectorized computer code for 3-D fluiddynamic and thermal-hydraulic analyses in cartesian and cylinder coordinates. It is related to the family of COMMIX codes originally developed at Argonne National Laboratory, USA. To a large extent, FLUTAN relies on basic concepts and structures imported from COMMIX-1B and COMMIX-2 which were made available to KfK in the frame of cooperation contracts in the fast reactor safety field. While on the one hand not all features of the original COMMIX versions have been implemented in FLUTAN, the code on the other hand includes some essential innovative options like CRESOR solution algorithm, general 3-dimensional rebalacing scheme for solving the pressure equation, and LECUSSO-QUICK-FRAM techniques suitable for reducing `numerical diffusion` in both the enthalphy and momentum equations. This report provides users with detailed input instructions, presents formulations of the various model options, and explains by means of ...

1991-05-01

121

Development of a production technology for PbSnCaAl alloys for batteries  

Energy Technology Data Exchange (ETDEWEB)

A new generation of lead alloys for making lead batteries is being introduced in highly developed countries. A very important characteristic of these alloys is the presence of Ca, Al and Sn. Such alloys have the property of stabilizing the amount of gas emitted as a result of the decomposition of the electrolyte on the level of pure lead i.e. significantly smaller than lead alloys containing Se e.g. PbSb 1.7Se. Such alloys have not been produced in Poland so far. - In this paper we are presenting the method and equipment used to produce a pilot portion of PbSnCaAl alloy (mass approximately 80 Mg) on an industrial scale at HMN ''Szopienice'' S.A. lead refinery. We also present the results of the tests regarding the chemical homogeneity of the alloy produced, as well as its structural and casting properties. On the basis of the tests conducted it has been found that the method is industrially adequate and as such it has been introduced into the ...

2000-07-01

122

Characterisation of biosorption to algae of heavy metals; Charakterisierung der Biosorption von Schwermetallen an Algen  

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The paper presents fundamental studies on natural biosorption to algae of heavy metals. The investigations were carried out by TU Berlin University in a special research project (Sfb 193, 'Biologische Behandlung industrieller und gewerblicher Abwaesser'). The chlorophyceae C. vulgaris was used as reference alga, and 38 further algae were analzyed with regard to their sorption characteristics for lead, cadmium, nickel and zinc. The most effective algae were the chlorophyceae C. salina, the cyanophyceae S. hofmani and L. taylorii. The biosorption characteristics of C. salina and L. taylorii were investigated in detail. L. taylorii was found to be exploitable successfully in a technical process, so the investigations were extended to include copper. Knowledge about the chemical processes of biosorption is important for any attempt to modify the biosorption characteristics. Experiments on the incorporation of additional functional groups in the cell wall polysaccharides ...

2003-07-01

123

Anthropogenic materials and products containing natural radionuclides. Pt. 2a. Investigation of occupational radiation doses. Specific and long-term measurements in a drinking-water conditioning plant; Anthropogene Stoffe und Produkte mit natuerlichen Radionukliden. T. 2a. Untersuchungen zur Strahlenexposition beim beruflichen Umgang. Detail- und Langzeitmessungen in einer Trinkwasseraufbereitungsanlage  

Energy Technology Data Exchange (ETDEWEB)

The measuring series was performed from November 1991 through April 1992 in seven drinking-water conditioning plants of the Fichtel mountains area in the north-eastern part of Bavaria, and the results revealed as an annual average a dose of about 1 - 40 WLM. The area of interest is a drinking-water catchment area where the ground water and other water resources include waters particularly rich in radon content, which explains this relatively high dose range. This is why comprehensive, specific local and long-term mearurements were carried out in order to assess the occupational radiation dose in the drinking-water conditioning plants, taking as a model site the conditioning plant of the municipal utilities of Hof in Weissenstadt. These more specific measurements were performed by the Technical Inspectorates (TUeV) of Bavaria and Saxony and the isotope laboratory of Georg-August University of Goettingen in mid-April 1994 (Goettingen University, TUeV Saxonia and Bavaria) and from June ...

1995-03-01

124

Investigation of dominant loss mechanisms in low-temperature polymer electrolyte membrane fuel cells  

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This thesis deals with the analysis of dominant loss mechanisms in direct methanol fuel cells (DMFC) and hydrogen fed polymer electrolyte membrane fuel cells (PEFC) by means of experimental characterization and modeling work. Due to different fuels used in these two fuel cell types, the dominant loss mechanisms are different in their nature. All in-situ characterization techniques that are used in this work are based on a novel test fuel cell with embedded reference electrodes. The first part of this work presents a new concept for realizing a reference electrode configuration in a polymer electrolyte membrane fuel cell by means of laser ablation. The laser beam is used to evaporate a small gap into the electrode surface of a catalyst coated membrane (CCM) to isolate the reference electrode from the working/counter electrode (WE/CE). This method enables the simultaneous ablation of the electrodes on both sides of the CCM because the membrane is transparent for the laser beam. ...

2010-07-01

125

Comparison of high resolution whole-body MRI using parallel imaging and PET-CT. First experiences with a 32-channel MRI system; Hochaufloesendes Ganzkoerpertumorstaging unter Verwendung paralleler Bildgebung im Vergleich zur PET-CT. Erste Erfahrungen auf einem 32-Kanal-MRT-System  

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To compare the accuracy in the detection and staging of various malignant tumors with high resolution whole-body MRI using parallel imaging with whole-body dual-modality PET-CT. Preliminary results of an interim analysis from a prospective, blinded study are presented, in which 20 patients (mean age 59 years, range 27-77 years) with different oncological diseases underwent whole-body dual modality FDG-PET-CT screening for tumor search or staging in case of confirmed or suspected metastatic disease. All patients also underwent whole-body MRI imaging with the use of parallel imaging (iPAT). High-resolution coronal T1w- and STIR-sequences of 5 body levels with 512 x 512 matrix, axial fast T2w imaging of lung and abdomen (HASTE), contrast-enhanced dynamic and static T1w-sequences of liver, brain, abdomen, and pelvis were performed. Using a 32-channel whole-body MRI scanner (Magnetom Avanto, Siemens Medical Solutions) with a total field of view of 205 cm and free table movement, all ...

2004-09-01

126

MRI-based N-staging in esophageal cancer; N-Staging des Oesophaguskarzinoms mittels MRT unter Verwendung von artefaktreduzierenden LOTA-Sequenzen  

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Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by ...

2002-10-01

127

Incidence of lesions as described by MRI in focal epilepsy of frontal and temporal onset; Inzidenz kernspintomographisch erfassbarer Laesionen bei der Abklaerung fokaler Epilepsien frontalen und temporalen Ursprunges  

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Aim: Today, MRI is an integral part of the presurgical evaluation of patients suffering from partial epilepsy. These patients frequently show focal morphological abnormalities with potential epileptogenic character and surgical resection of these lesions is associated with superior postsurgical outcome as to seizure frequency. Apart from easily detectable defects, such as post-traumatic lesions or cerebral infarction, as wide variety of mainly small abnormalities can be detected using MRI. Methods: In this study, 484 patients suffering from partial epilepsy of temporal or frontal onset were evaluated for the incidence of different lesions in this population. Results: All lesions found were included without evaluating their potential epileptogenicity, which remains to be proven using other procedures (EEG, SPECT, PET, etc.). Involvement of the hippocampal formation was a major finding in temporal lobe epilepsy, which could be detected as sclerosis (T2w-images), atrophy (T2w-TSE or ...

1997-09-01

128

High-efficiency, thin-film- and concentrator solar cells from GaAs. Final report; High-efficiency, Duennschicht- und Konzentrator-Solarzellen aus Galliumarsenid. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

Main topic of the project was the manufacturing of highly efficient GaAs-solar cells and the fabrication of concentrator cells. During this process significant progress was made with the material preparation, the solar cell technology and the material and process characterisation. This succeeded in the following efficiencies: - GaAs solar cell made by MOVPE technology: 22.9% on 4 cm{sup 2} (AM1.5g) - GaAs solar cell made by LPE-ER process: 22.8% on 4 cm{sup 2} (AM1.5g) - GaAs concentrator solar cell made by LPE-ER process: 24.9% at C=100xAM1.5d - GaAs concentrator module with fresnel lenses: Module efficiency 20.1% (under irradiation of 793 W/m{sup 2}). Another main focus was the epitaxy of GaAs on Si substrate. Two different approaches were investigated. Together with the cooperation partner ASE, Heilbronn a selective growth technology was developed that led to a decreased crack formation. By a simultanous optimization of the other epitaxy and process parameters, the efficiency was ...

1996-10-01

129

Fission product speciation in Phebus tests FPT0 and FPT1 and the possible influence of boron  

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The thermochemical calculations performed with a large number of elements to describe the chemical system in a Phebus FP test allow the following conclusions: The metallic absorber materials play a significant role in fission product speciation. At around 1000 C and above, silver iodide is the dominant iodine carrier in a full steam atmosphere in both FPT0 and FPT1. At lower temperatures, cadmium iodide takes over. In a reduced environment, indium iodide becomes important. Caesium iodide does certainly appear; at certain test conditions it becomes the major iodine transporting vehicle. But its role is not greater than that of the other iodides. It has more chances in FPT1 than in FPT0. Chlorine, which was present in FPT0 as a contaminant in relatively large amounts, does not prevent the iodine from forming Csl. Both share the caesium like partners. The evolution of caesium chloride and iodide proceeds in parallel. When CsCl is abundant, Csl is strong, too. Should boron be added to the ...

1996-01-01

130

Three-dimensional evaluation of cartilage thickness and cartilage volume in the knee joint with MR imaging: reproducibility in volunteers; Dreidimensionale Dicken- und Volumenbestimmung des Kniegelenkknorpels mit der MRT: Reproduzierbarkeit am Probanden  

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Objective: To determine the reproductibility of three-dimensional volume and thickness measurements of the knee joint cartilage with MRI in volunteers. Methods: The knees of 7 healthy individuals (ages 23 to 58 yrs.) were sagitally imaged with a resolution of 2x0.31x0.31 mm{sup 3}, using a fat-suppressed FLASH-3 D sequence. The knee was repositioned in between replicate acquisitions, 6 data sets being obtained in each case. After semiautomatic segmentation and three-dimensional reconstruction of the cartilage, the thickness was determined independent of the original section orientation. The coefficient of variation for repeated volume measurements and the deviations of the maximal cartilage thickness values were calculated subsequently. Results: The mean variation of the cartilage volumes of the replicate measurements was 1.4% ({+-}0.8%) in the patella, 1.7% ({+-}1.5%) in the femur, 3.0% ({+-}1.2%) in the medial tibial plateau and 3.5% ({+-}2.0%) in the lateral tibial plateau. The ...

1997-12-01

131

The role of high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in the diagnosis of preoperative and postoperative complications caused by acquired cholesteatomas; CT und MRT des erworbenen Cholesteatoms: Prae- und postoperative Bildgebung  

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The role of high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in the diagnosis of preoperative and postoperative complications caused by acquired cholesteatomas will be described in this paper. The pre- and postoperative imaging of the temporal bone was performed with HRCT and MRI. HRCT and MRI were performed in the axial and coronal plane. MRI was done with T2 weighted and T1 weighted sequences both before and after the intravenous application of contrast material. All imaging findings were confirmed clinically or surgically. The preoperative cholesteatoma-caused complications depicted by HRCT included bony erosions of the ossicles, scutum, facial canal in the middle ear, tympanic walls including the tegmen tympani, and of the labyrinth. The preoperative cholesteatoma-caused complications depicted by MRI included signs indicative for labyrinthitis, and brain abscess. Postoperative HRCT depicted bony erosions caused by recurrent cholesteatoma, bony defects ...

2003-03-01

132

TRITEX. A ferritic steel loop with Pb-15.8Li. Facility and operation  

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TRITEX was a pumped loop with Pb-15.8Li, fabricated from steel 1.4922. In contact with the molten eutectic were also molybdenum, vanadium and armco-iron. The loop was originally designed to investigate tritium extraction using solid getter metals. Over the years the goal changed to the study of metals, corrosion products and purification of the eutectic mixture. Therefore many modifications were done. The first part of this report describes TRITEX. All parts were enclosed in thermoboxes for a homogeneous temperature. One test section was in an argon glove box and could be opened during operation. Other special equipment`s were: permeation membranes and liquid-metal-covergas-interfaces to study the transport of H{sub 2}, D{sub 2} and {sup 3}H, different purification devices, a quartz observation window to see the liquid metal surface, 4 different kinds of flow measurements, level indicators, freeze valves. The second part describes loop operation. Between 1989 and 1996, the eutectic ...

1999-05-01

133

Stent placement under real-time MR control: first experience in an animal model; Stentplazierung unter Echtzeit-MR-Kontrolle: erste tierexperimentalle Erfahrungen  

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Purpose: The aim of this study was to test the feasibility of iliac artery stent placement under MR guidance with real-time MR radial scanning in an animal model. Materials and methods: The experiments were performed on three pigs in a 1.5 T scanner. Radial scanning with a gradient echo technique (T{sub R} 8.4 ms, T{sub E} 3.6 ms, flip angle 10 ) was used. A dedicated backprojector performed the reconstruction of the raw data in real-time. The resulting MR-images were displayed on LCD screens beside the magnet. The sliding window reconstruction technique allowed image acquistion at a frame rate of 16 images per second. MR-compatible self-expanding stents with a diameter of 8 mm and a length of 3 cm were placed into the left iliac artery. Their positions were verified by digital subtraction angiography (DSA) and compared to MRI. Results: All stents were successfully placed. Stent positions as monitored by real-time MR were identical to those seen on DSA images. The time needed for exact ...

1998-12-01

134

Staging of multiple myeloma with MRI: comparison to MSCT and conventional radiography; Staging des multiplen Myeloms mit der MRT: Vergleich zur MSCT und zur konventionellen Roentgendiagnostik  

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The staging of patients with multiple myeloma demands sensitive imaging methods for the assessment of the skeletal system. MRI allows for direct visualization of the bone marrow which exhibits five different infiltration patterns in multiple myeloma: 1. normal appearance of the bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. ''salt and pepper'' pattern with inhomogeneous bone marrow signals due to multiple fat islands. The combination of T1w-SE and STIR sequences is best suited for detecting all infiltration patterns and for the differential diagnoses e. g. hemangiomas. With parallel imaging in MRI, acquisition times can be markedly reduced and whole-body screening of the bone marrow can be achieved within 30 min. MRI is superior to radiography for the detection of focal as well as diffuse infiltration. Multidetector computed tomography and especially 16- and 64-detector row ...

2004-09-01

135

Radioprotection through cytokineliberation under N-actylcysteine; Radioprotektion durch Zytokinfreisetzung unter N-Acetylcystein  

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Backgrund: Interleukin-1, tumornecrosisfactor-{alpha} and interferon-{gamma} endogenously provide protection of the hematopoietic system against radiation. Thiols have already been used successfully as radioprotective agents. In this study the effect von N-acetylcysteine (NAC) on the release of interleukin-1{alpha} and {beta} (IL-1), interleukin-2 (IL-2), interferon-{gamma} (IFN-{gamma}) and tumornecrosisfactor-{alpha} (TNF-{alpha}) was assessed in an in vitro assay. Patients and Methods: Whole blood samples from 8 healthy volunteers were stimulated with 7.5 {mu}m/ml PHA. NAC was added at concentrations of 0.6, 6, 12 and 24 mmol/l. Subsequently the samples were irradiated with a dose of 18 Gy according to preceding validation experiments. Results: IL-1{alpha}, IL-1{beta} and IL-2: In comparison to simulation and radiation alone the addition of 0.6 and 6 mmol/l with IL-2 also 12 mmol/l, NAC resulted in a significant increase of the cytokine-concentrations. The highest concentration of ...

1996-02-01

136

Percutaneous therapy of inoperable biliary stenoses and occlusions with a new self-expanding nitinol stent (SMART); Perkutane Therapie inoperabler maligner Stenosen und Verschluesse der Gallenwege mit einem neu entwickelten selbstexpandierbaren Nitinolstent (SMART)  

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Objective: To evaluate the treatment of malignant biliary stenoses and occlusions using a new stent. Methods: In a prospective study, 25 patients with malignant obstructive jaundice were treated with SMART stents. The handling and the quality of stent expansion were documented. Stent function was assessed 2-4 days after intervention by cholangiography and laboratory tests. A follow-up was performed three months, after stent placement. Results: All lesions were treated successfully, with a total of 35 stents implanted. In 14 patients a further balloon dilatation was performed after stent placement (8-10 mm diameter/40-80 mm length). The mean serum bilirubin level decreased significantly from 11.6 mg/dl to 4.6 mg/dl after intervention (p<0.05). The follow-up showed a mean serum bilirubin level at 4.0 mg/dl. In 4 cases (16%) a further intervention (PTCD or stent) was performed. Six patients died due to tumor progression. The stents proved to be patent in 79% (n=15) of patients ...

2002-10-01

137

Molybdaen-targets in the Research Centre J``ulich; Erzeugung von Molybdaen fuer die Medizin im FRJ-2 des Forschungszentrums Juelich  

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From autumn this year, the FRJ-2 of the Research Center Juelich will be supplying molybdenum targets to the Institut National des Radioelements in Fleurus, Belgium - which deals in medical radio-isotopes worldwide - thus helping to meet the need for technetium-99, which is used in the medical profession for diagnostic purposes because of its favourable radiological characteristics. Technetium-99 is formed as a result of the radioactive decay of molybdenum-99. For many years now, molybdenum has been produced by the irradiation of uranium in research reactors, so that the initiation of molybdenum production in the FRJ-2 is not especially new. What is unusual, however, are the particular peripheral conditions which result from the combination of the irradiation requirements, a predetermined target design and the technical characteristics of the reactor and which necessitated special solutions. This applies especially to the handling of the targets after irradiation, which is much more ...

1999-06-01

138

MRT versus CT in the diagnosis of pneumonia. Evaluation of a T{sub 2}-weighted utrafast turbo-spin-echo sequence (UTSE); MRT versus CT in der Diagnostik von Pneumonien. Evaluation einer T{sub 2}-gewichteten ultraschnellen Turbo-Spin-Echo-Sequenz (UTSE)  

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Purpose: To evaluate a T{sub 2}-weighted URSE sequence for the assessment of pulmonary infiltrations in comparison to CT. Methods: 28 MRT scans of 22 patients with confirmed pneumonia were recorded on a 1.5 Tesla apparatus with an expiratory and diastolic triggered, T{sub 2}-weighted ultrafast-spin-echo sequence in axial slice mode with the following parameters: TR{sub eff}/T{sub E}/Turbofactor 2000-4000/90 ms/21-23; slice thickness/separation 6/0.6 mm; FOV 360 mm; 24 slices. 24 spiral CTs (sice thickness/table advance: 1-2 mm/10 mm) were available for comparison. The separate evaluation of MRTs and CTs was performed by three radiologists in a consensus procedure with regard to pulmonary lesions (e.g., infiltration, round foci, net patterns) and image quality of the MRTs (4-step scale). Results: In 71% of the cases the CTs and MRTs agreed with the diagnosis and representation of the lesions, in 25% MRT was superior. MRT was better for the detection of pulmonary abscesses. In 93% the ...

1999-05-01

139

MRI in definition of bleeding source, lesion pattern and therapy in haemarthros of the knee; Die MRT beim Haemarthros des Kniegelenks: Bestimmung von Blutungsursachen, Verletzungsmustern und Therapie  

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Patients with haemarthros of the knee were examined by MRI and arthroscopy to identify the bleeding source and to determine surgical or conservative therapy. A prospective study was performed on 120 patients who underwent MRI and arthroscopy, point lesions and bleeding sources were documented separately on a standardised form. Arthroscopy demonstrated a ruptured anterior cruciate ligament in 86%, meniscal tears in 55%, disruption of collateral ligaments in 17%, osteochondral lesions in 5% and tears of capsule or plicae in 13%. Disruption of cruciate ligaments caused haemorrhage in all but three cases. In contrast, only meniscal tears located very adjacent to the meniscal basement had bled. Those types of osteochondral lesions caused haemorrhage characterised on MRI by destruction of the subchondral plate and overlying cartilage. Severe lesions of the knee were diagnosed by MRI in 71% to 100%, slight lesions in 13% to 40% of the cases. Single, combined and bland lesions were accurately ...

1996-09-01

140

Isothermal high-temperature fatigue tests on {gamma}-TiAl in different atmospheres; Isotherme Hochtemperaturermuedungsversuche an {gamma}-TiAl in unterschiedlichen Atmosphaeren  

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{gamma} Ti-Al have a higher temperature potential than commercial titanium alloys and a 50 percent lower density than nickel base superalloys. Application temperatures in aircraft turbines are 750 C and above. The authors investigated the high-temperature performance of {gamma} TiAl, i.e. isothermal high-temperature fatigue and the type and importance of damage. LCF experiments were made in the temperature range of brittle/ductile transition in air and vacuum. Damage mechanisms were characterized by microstructural investigations. [German] Unter den modernen Hochtemperaturwerkstoffen kommt den Legierungen auf Basis von {gamma}-TiAl eine zunehmend wichtige Bedeutung zu, da diese Werkstoffe ein hoeheres Temperaturpotential als alle kommerziellen Titanlegierungen haben und eine im Vergleich zu den Nickelbasis-Superlegierungen um ca. 50% geringere Dichte aufweisen. TiAl-Werkstoffe, die z.B. fuer Schaufeln und Gehaeuse in Flugzeugturbinen eingesetzt werden sollen, muessen bei Temperaturen ...

1999-07-01

141

Globalisation of the nuclear fuel cycle - impact of developments on fuel management  

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Nuclear energy will have to cope more and more with a rapid changing environment due to economic competitive pressure and the deregulatory progress. In current economic environment, utilities will have to focus strongly on the reduction of their total generation costs, covering the fuel cycle costs, which are only partly under their control. Developments in the fuel cycle will be in the short-term rather evolutionary addressing the current needs of utilities. However, within the context of sustainable development and more and more inclusion of externalities in energy generation costs, more performing developments in the fuel cycle could become important and feasible. A life-cycle design approach of the fuel cycle will be requested in order to cover all factors in order to decrease significantly the nuclear energy generation cost to complete with other alternative fuels in the long-term. This paper will report on some of the trends one could distinguish in the fuel cycle with emphasis ...

2000-02-01

142

Development of a system for the observation of the stable operation in multi stage axial compressors. Final report; Erprobung und Weiterentwicklung eines Messsystems zur Stabilitaetsueberwachung im Verdichter einer HTGT. Abschlussbericht  

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This report describes work carried out in the context of TurboTech Interim for the development of a system for monitoring stationary gas turbines for approaching the stability limit of the compressor. The requirements for the system components were defined and the suitability of different types and positions of pressure sensors were examined and evaluated. It was found very early in the work that, due to the complexity of the object being monitored, one would not succeed in finding a simple criterion for monitoring the pump limit. Rather, apart from the selection of suitable sensors and optimum positions, one must analyse the present signals in different ways and create a decision matrix from this. Existing work on this subject is mostly concerned with the phenomena in the context of experiments on experimental compressors or is not suitable for the requirements of stationary industrial gas turbines. The project is being carried out in the context of TurboTech II with the main aims of: ...

1996-12-31

143

Correlation between the microstructure and the physical properties of HTSC single crystals and films. Final report; Korrelation zwischen der Realstruktur und den physikalischen Eigenschaften von HTSL-Einkristallen und -Schichten. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

1. In order to carry out isothermic crystal growth experiments of YBCO the 123 primary crystallization field was determined by means of phase diagram investigations and crystal growth experiments at different oxygen partial pressure. 2. YBCO single crystals of high crystallographic perfection were grown and conclusions on the flux pinning mechanism were drawn. 3. By means of Liquid Phase Epitaxy (LPE) single crystalline (Tc{approx}90 K; {Delta}T{<=}0.5 K) c- and a,b- YBCO fils have been prepared on NdGaO{sub 3} and LaGaO{sub 3} substrates. The films were characterized structurally and magnetically. 4. Our fist melt textured YBCO ``single crystals`` possess intracrystalline critical current densities >10{sup 4} A/cm{sup 2} at B{<=}2T. The irreversibility inductions are {<=}6 T at 77 K. A simple demonstrator was constructed together with the IFW Dresden and a growth model was developed. 5. Using above all torque magnetometer measurements we separated intrinsic pinning effects ...

1993-06-01

144

Computed tomography and magnetic resonance imaging of acquired abnormalities of the inner ear and cerebello-pontine angle; CT und MRT erworbener Veraenderungen des Innenohrs und Kleinhirnbrueckenwinkels  

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CT and MRI of acquired abnormalities of the inner ear and cerebello-pontine angle present themselves with very typical findings. The imaging should be adapted to the pathology looked for and either CT or MRI should be used alone or in combination.CT, especially high resolution CT (HRCT), provides an excellent bone contrast, while MRI has a much superior soft tissue contrast. Acute inflammatory changes of the inner ear are solely depicted by contrast-enhanced MRI. HRCT excellently depicts osseous changes of the inner ear and cerebellopontine angle such as chronic ossifying labyrinthitis occurring after acute labyrinthitis, otosclerotic or traumatic changes. Tumorous changes not yielding to bony changes are best delineated by MRI. Posttraumatic hemorrhage and chronic fibrotic changes within the labyrinth are depicted by MRI, only. In conclusion HRCT and MRI are excellent methods to delineate acquired abnormalities of the inner ear and cerebello-pontine angle. HRCT best depicts osseous ...

2003-03-01

145

A new concept for covered stent protected carotid angioplasty: an ex vivo study  

Energy Technology Data Exchange (ETDEWEB)

Objective: To determine the efficacy of a covered stent prototype designed for protected carotid angioplasty to reduce cerebral embolization. Material and Method: The covered stent tested is made of nitinol, coated with a polyurethane membrane (MembraX{sup TM}; porous size 80 {mu}m). In a bench-top model (flow-rate 650 ml/min, pulsatile flow [dicrote] 123 Pulses/min, pressure 100/60 mm Hg [mean pressure 80 mmHg]) with inserted human carotid (n=6) stent implantation was performed (8/32 mm). Passed particles (mg) were determined in the effluent of a 100 {mu}m filter prior to intervention, after stent deployment and after final dilation (5 mm). Results: When stenting carotid arteries obtained from human cadavers, the highest rate of particle embolization was measured while crossing the lesion with the delivery device (6,8 mg; for all p<0,05), embolization after additional balloon angioplasty and particle rates measured in the effluent filter prior covered stent placement were ...

2003-12-01

146

Waste laws. Waste Classification Ordinance. Residual Material Classification Ordinance. The Waste Technical Code. Ordinance on the Monitoring of Wastes and Residual Material. Ordinance on the Ban on CFCs and Halogenated Hydrocarbons. Packaging Ordinance. Sewage Ordinance. Text edition with index and an introduction by Dr. Clemens Weidemann. As of May 15, 1992. Abfallgesetz. AbfallbestimmungsV. ReststoffbestimmungsV. TA Abfall. Abfall- und ReststoffueberwachungsV. FCKW-Halon-VerbotsV. VerpackungsV. KlaerschlammV. Textausgabe mit Sachverzeichnis und einer Einfuehrung von Rechtsanwalt Dr. Clemens Weidemann. Stand: 15. Mai 1992  

Energy Technology Data Exchange (ETDEWEB)

The turbulent history of legislature concerned with the waste-management industry and the amount of material on this subject as well as the significance of the material in its own right led to the decision to publish all legal regulations on waste in one volume. It includes above all the Waste Law, Regulations on Determination of Waste, Regulations on Determination of Residual Products, Technical Instructions for Waste, Regulations for Monitoring Waste and Residual Products, Regulations on Probition from the Use of Chlorofluorohydrocarbons and Halon, Regulations on Packaging and Regulations on Sewage Sludge. The introduction explains the development and the role of the Waste Law and its applicability, goals and principles: The concept of waste, avoidance of waste, avoidance of waste tourism, the general welfare of the public; regulations on waste management, governmental means of monitoring waste management: Obligations to dispose of waste, compulsory waste-management plants and ...

1992-01-01

147

Von Roll RCP method - first experiences; Von Roll RCP - Verfahren. Erste Erfahrungen  

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The RCP method was designed as a residue-optimised alternative to the thermally optimised grate firing of residual wastes. Its technical realisation and development to market maturity took no more than 5 years. In the first process stage the waste is converted to high-carbon pyrolysis charcoal and high-rank gas in the absence of oxygen. In the second stage these substances are oxidised by addition of oxygen. The resulting temperature causes the non-combustible constituents of the slag to melt. In a third, optional, stage this molten slag can be liberated of (heavy) metals to such an extent that it can subsequently be used directly as additive for grinding. Further exhaust gas treatment is facilitated by the use of a circulatory fluidised-bed secondary combustion chamber. Despite the reduced flue gas volume and resultant higher pollutant concentrations in the crude gas, overall emissions are lower than in conventional plants. [Deutsch] Das reststoffoptimierte RCP Verfahren ist als ...

1998-09-01

148

Transparent thermal insulation for a fabrication hall of LHB, Salzgitter; Transparent gedaemmte Fertigungshalle bei LHB in Salzgitter  

Energy Technology Data Exchange (ETDEWEB)

Many industrial workshops in Germany were erected during the 40s and 50s, especially at the beginning of the economic boom. After more than 40 years, these facilities are in need of structural and production-technical modernization. A case in point is the carriage fabrication workshop of the Salzgitter-based company Linke-Hoffmann-Busch. The characteristic features of this type of building are large glazed areas, free uncontrolled ventilation and substantial height. Opportunities for energy-oriented and light-technical modernization are demonstrated at this Salzgitter workshop in exemplary form, the emphasis being on the use of solar energy components and, particularly, transparent thermal insulation. (orig.) [Deutsch] In der Bundesrepublik Deutschland gibt es viele Produktionshallen, die in den vierziger und fuenfziger Jahren, insbesondere zu Beginn des wirtschaftlichen Aufschwungs, errichtet wurden. Diese Hallen sind nach ueber vierzig Jahren sowohl aus baulichen als auch ...

1997-12-31

149

Time measurement - technical importance of most exact clocks; Zeitmessung - Die technische Bedeutung der genauesten Uhren  

Energy Technology Data Exchange (ETDEWEB)

The exactness of the best atomic clocks currently shows a temporal variation of 1 second in 30 million years. This means that we have reached the point of the most exact frequency and time measurement ever. In the past, there was a trend towards increasing the exactness in an increasingly fast sequence. Will this trend continue? And who will profit from it? This article is meant to give answers to these questions. This is done by presenting first the level reached currently with the best atomic clocks and describing the research activities running worldwide with the aim of achieving even more exact clocks. In the second part, we present examples of various areas of technical subjects and research in which the most exact clocks are being applied presently and even more exact ones will be needed in the future. [German] Die Genauigkeit der derzeit besten Atomuhren entspricht einer Sekunde Unsicherheit in 30 Millionen Jahren. Damit erlauben Frequenz- und Zeitmessungen ...

2004-12-15

150

Thermomechanical fatigue of coated single-crystalline materials; Thermomechanische Ermuedung beschichteter Einkristallwerkstoffe  

Energy Technology Data Exchange (ETDEWEB)

The interdiffusion behaviour of MCrAlY-coats on polycrystalline and single-crystalline materials of a similar composition (IN 738 LC/SC 16)shows similar interdiffusion characteristics. TCF-tests, where stress is generated by temperature and sample geometry at the edges of a disk-shaped sample, show that it is possible to differentiate betwee crack resistance of coated and uncoated samples. This method is also suitable for screening tests with different coat thicknesses. Coating of the edge area must, however, be done with great diligence in order to prevent coat thickness variation as results would then not be reproducable. Contrary to TCF (thermal cycle fatigue) TMF-tests (thermal mechanical fatigue)allow to set the stress states that one wishes to test. This method is therefore well suited for testing under operating conditions.(orig.) [German] Im Rahmen dieser Arbeit wurde gezeigt, dass das Interdiffusionsverhalten von MCrAlY-Schichten auf polykristallinen bzw. ...

1998-07-01

151

Thermodynamic model of the gas and steam process with combined heat and power process; Thermodynamisches Modell des GuD-Prozesses mit Kraft-Waerme-Kopplung  

Energy Technology Data Exchange (ETDEWEB)

A whole sequence of the parameters of the combined heat and power system (KWK) is described which enables a comparison between the electricity and heat demand of a consumer and the energy availability through a combined heat and power system. Proceeding from this, a thermodynamic model of a steam and gas process with combined heat and power is introduced which is based on an exergetic balancing of the subsystems of the process. In this way, the varying thermodynamic quality of the energy flows occuring in the process will be taken into consideration so that the results of the model correspond in any case with the second law of thermodynamics. (orig.) [Deutsch] Es wird ein vollstaendiger Satz von Kenngroessen der Kraft-Waerme-Kopplung (KWK) beschrieben, mit dessen Hilfe der Strom- und Waermebedarf eines Verbrauchers mit der Energiebereitstellung durch eine KWK-Anlage verglichen werden kann. Darauf aufbauend wird ein thermodynamisches Modell des GuD-Prozesses mit Kraft-Waerme-Kopplung ...

1996-03-01

152

The value of high-resolution MR-imaging for the staging of malignant lesions of tongue, pharynx and larynx; Klinische Wertigkeit der hochaufloesenden Magnetresonanztomographie beim Staging von Tumoren der Mundhoehle, des Pharynx und des Larynx  

Energy Technology Data Exchange (ETDEWEB)

In a prospective study 102 patients with malignant tumors of the tongue, oropharynx, hypopharynx, and larynx were staged by means of MRI. Special attention was directed at those tumour extensions that could influence the treatment strategy. The MR findings were correlated with the results of palpation, endoscopy, ultrasound, computerised tomography and histopathological findings. MRI showed a good delineation of pT{sub 2} to pT{sub 4} tumours. However, visualisation of small tumours in the soft palate, the tonsils, the pyriform sinuses and vocal cords was difficult. In conclusion our results suggest that in addition to endoscopy MRI is a valuable tool for the examination of tumours of tongue, oropharynx, hypopharynx and larynx. (orig.) [Deutsch] In einer prospektiven Studie wurden 102 Patienten mit malignen Tumoren der Mundhoehle, des Oro- und Hypopharynx sowie des Larynx mit der Mgnetresonanztomographie (MRT) untersucht, wobei besonders Wert auf die Bestimmung ...

1994-02-01

153

The coal mining industry in the north of Colorado and Arizona; Steinkohlenbergbau im Norden Colorados und Arizonas  

Energy Technology Data Exchange (ETDEWEB)

A study tour in autumn 1999, which was undertaken following the award of the Helmuth Burkhardt prize of Wirtschaftsvereinigung Bergbau e.V. to the authors, comprised visits to potash, molybdenum, lead, zinc, copper ore and coal mines in the mid-west of the USA. The Black Mesa Mine and Kayenta Mine of Peabody Western Coal Company in the Navajo Reserve in the north of Arizona, the Trapper Mine Inc. near Craig and the Twentymile Coal Company near Steamboat Springs, Colorado are described in this report. In addition to a brief description of the geology the coal winning is considered in greater detail. The Twentymile Coal Company was asked to explain the reasons for the successful operation of the colliery, which produces more than 5 mill. t anthracite per year by long wall working. (orig.) [German] Eine Exkursion im Herbst 1999, die durch die Verleihung des Helmuth-Burkhard-Preises der Wirtschaftsvereinigung Bergbau e.V. an Bergassessor Andreas Tschauder zustande kam, fuehrte zu Kali-, ...

2000-10-12

154

The Voelkersen gas field in northern Germany: Are there two directions of stress in the red sandstone?; Das Voelkersen Gas Feld in Norddeutschland: Anzeichen fuer zwei Spannungsrichtungen im Rotliegenden?  

Energy Technology Data Exchange (ETDEWEB)

Borehole stability is affected to a significant extent by the 3D local and regional stress field. Preliminary information on underground stress fields is provided by the World Stress Map, which shows N-NW stress at a depth of about 5000 m for the Voelkersen field. Earlier data analyses showed various directions in the range of 310-360 degrees. This was assumed to be a methodical error. An extensive study was carried out to evaluate and interpret all relevant information provided by borehole tests, borehole logs, and drill core measurements. [German] Standsicherheit und Stabilitaet von Bohrungen werden ganz wesentliche beeinflusst durch das umgebende dreidimensionale lokale und regionale Spannungsfeld. Fuer die Planung zukuenftiger (horizontaler) Bohrungen und die Erzeugung kuenstlicher Risse (''fracs'') spielt das Spannungsfeld eine bedeutende Rolle. Erste Hinweise ueber das regionale Spannungsfeld im Untergrund gibt die World Stress Map, in der ...

2003-07-01

155

Structure of energy supply, energy analysis, projections for energy demand development and for emission-reducing energy carrier application in powered vehicles in the district Schmalkalden-Meiningen; Struktur der Energieversorgung, Energieanalysen, Prognosen zur Energiebedarfsentwicklung und zum emissionsmindernden Energietraegereinsatz fuer Kraftfahrzeuge im Landkreis Schmalkalden-Meiningen  

Energy Technology Data Exchange (ETDEWEB)

The present publication is based on facts, data, knowledge and projects, which have been incorporated in the development of an energy concept for the district Schmalkalden-Meiningen. The energy concept of a district is a concept oriented at action on and realisation of mid-term and long term decisions in the fields of energy policy, economy and ecology, which must be taken by municipal and economic decision-making bodies. The energy concept accords with the targets of the Agenda 21, the environmental targets of the Federal Republic of Germany and of the Land Thuringia. Accepting this energy concept the district Schmalkalden-Meiningen shows its willingness to contribute to a lasting development in all fields of economy and ecology and thus does justice to its increasing responsibility. (orig.) [German] Die vorliegende Veroeffentlichung baut auf Fakten, Daten, Erkenntnissen und Projekten auf, die in die Erarbeitung des Energiekonzeptes fuer den Landkreis Schmalkalden-Meiningen ...

2001-07-01

156

Solar hybrid systems in a residential estate of terraced houses near the Wannsee railway in Berlin; Solare Hybridsysteme in einer Reihenhaus-Wohnanlage an der Wannseebahn in Berlin  

Energy Technology Data Exchange (ETDEWEB)

The aim of the study was to establish by means of a measuring programme how much energy for space heating can be saved by the installed hybrid system. Further, experience with the systems was to be gathered under practical use conditions. As user behaviour can influence space heating energy consumption to an extent having several times the effect of the contribution of the hybrid system, a fact that is also reported in literature, it is not sufficient to measure only space heating energy consumption. So, a unit in one of the terraced houses was scrupulously measured. In the three other terraced houses, only space heating energy consumption was measured.- This final report contains not only a description of the concepts of the buildings and hybrid system but also the energy consumptions measured, and detailed analyses of the budgets. (orig./AKF) [Deutsch] Mit Hilfe eines Messprogrammes sollte ermittelt werden, welche Heizwaermeeinsparung durch das installierte Hybridsystem praktisch ...

1997-08-31

157

Slide rings made of an SiC/silicide composite; Gleitringe aus einem SiC/Silicid-Verbundwerkstoff  

Energy Technology Data Exchange (ETDEWEB)

The objective of the project was to develop an infiltration material based on SiC that should have improved corrosion resistance and should permit higher operating temperatures. From a variety of tested doping agents, zirconium silicide and molybdenum proved to be the most appropriate agents. The respective infiltration materials permit a combination of advantages of the SSiC with those of the SiSiC. Silicide SiC, analogous to the SiSiC, is almost nonshrinking, and above all is more corrosion-resistant than SiSiC in the alkaline regime, due to the replacement of free silicon by silicide phases. The operating temperature of the molybdenum-base variant is 1600 C. (orig./CB) [Deutsch] Ziel des Vorhabens war die Entwicklung eines Infiltrationswerkstoffes auf SiC-Basis mit verbesserter Korrosionsbestaendigkeit und hoeherer Einsatztemperatur. Aus einer Vielzahl von getesteten Dotierungsmoeglichkeiten kristallisierten sich Zirkondisilicid und Molybdaen als geeingete ...

1997-12-31

158

Results of a cross-sectional study on the association of electromagnetic fields emitted from mobile phone base stations and health complaints; Ergebnisse einer Querschnittsstudie zum Zusammenhang von elektromagnetischen Feldern von Mobilfunksendeanlagen und unspezifischen gesundheitlichen Beschwerden  

Energy Technology Data Exchange (ETDEWEB)

Background: Despite the fact that adverse health effects are not confirmed for exposure to radiofrequency electromagnetic field (RFEMF) levels below the limit values, as defined in the guidelines of the International Commission on Non-Ionizing Radiation Protection, many persons are worried about possible adverse health effects caused by the RF-EMF emitted from mobile phone base stations, or they attribute their unspecific health complaints like headache or sleep disturbances to these fields. Method: In the framework of a cross-sectional study a questionnaire was sent to 4150 persons living in predominantly urban areas. Participants were asked whether base stations affected their health. Health complaints were measured with standardized health questionnaires for sleep disturbances, headache, health complaints and mental and physical health. 3,526 persons responded (85%) to the questionnaire and 1,808 (51%) agreed to dosimetric measurements in their flats. Exposure was measured in 1,500 ...

2010-07-01

159

Prospective benefit and effect of lipiodol marking in hepatocellular carcinoma; Moeglicher Nutzen und Auswirkung einer Lipiodolmarkierung auf die Histologie beim hepatozellulaeren Karzinom  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To assess the benefit and the effect of intraarterial lipiodol application on histological analysis of patients suspected of having HCC. To determine whether lipiodol marking leads to a better biopsy result and how lipiodol or a transarterial chemoembolization influences the histological diagnosis. Materials and Methods: Two groups of patients were examined. Group A included 14 patients highly suspected of having an HCC which had previously been unsuccessfully biopsied. A transarterial embolization with lipiodol was performed in these patients to mark intrahepatic tumors which could not otherwise be defined in unenhanced CT. A biopsy was then repeated. Group B included 22 patients undergoing therapy using transarterial chemoembolization (TACE). A biopsy was performed to support the diagnosis of a multifocal HCC before changing the therapy. Results: The transversal diameters of the biopsied tumors were similar in both groups (A: 22 mm; B: 21 mm). The length of percutaneous ...

2005-10-01

160

Preparation and separation of Tc-97 and development and application of a mass spectrometrical isotope dilution analysis for trace analysis of technetium, molybdenum and ruthenium. Herstellung und Isolierung von /sup 97/Tc sowie Entwicklung und Anwendung einer massenspektrometrischen Isotopenverduennungsanalyse zur Technetium-, Molybdaen- und Rutheniumspurenanalyse  

Energy Technology Data Exchange (ETDEWEB)

The thesis explains the development of a mass spectrometerical isotope dilution analysis (MS/DA) for determining trace amounts of Tc. The Tc-97 isotope has been prepared by in-core irradiation of Ru of natural isotopic composition, and used as the indicator isotope. For separation of Tc-97 from the Ru matrix, a method has been developed to quantitatively separate Tc-97 from a high Ru surplus. For determining the isotope ratio for the MS/DA, a mass spectrometrical measuring technique has been found which allows reproducible measurement of the Tc-99/Tc-97 isotope ratio. Positive and, for the first time, also negative thermoionisation has been used as a method of selective ionisation of Tc. The applicability of the MS/DA for Tc trace analysis has been verified using two Al foils doped with Tc-99 or Mo-98, respectively. These have been irradiated in a nuclear reactor, the irradiation of Tc-99 yielding Ru-100, and irradiation of Mo-98 Tc-99. The determination of the elements Ru and Mo in ...

1984-01-01

161

PDIM - multifunction regulator; PDIM - Die integrierte Druckreduzier- und Messanlage fuer Gas  

Energy Technology Data Exchange (ETDEWEB)

The PDIM multifunction regulator offers in one single unit the basic functions filtering, slamshut safety valve, pressure reduction and a gas flow straightening vane. This concept formulated by the engineer J.-P. Cornil is a Gaz de France patent. Developed and manufactured by a French industrial company it incorporates some astute innovations in the field of fluid dynamics. Its technical caracteristics make a significant step forward in gas technology. Since the first unit was brought into service over 1000 PDIM units have been built and incorporated in gas regulating and metering stations for transport, distribution and industrial applications. The very compact nature of the PDIM enhanced by its direct bolting to a turbine or other type of gas meter leads to small size stations allowing lower cost projects and making it easier to set in populated or architecturally significant areas. (orig.) [Deutsch] Der PDIM ist eine Verschmelzung der Funktionselemente Gasfilter, ...

1997-12-31

162

Osteonecrosis of the hip joint in adults; Die Osteonekrose des Hueftgelenks im Erwachsenenalter  

Energy Technology Data Exchange (ETDEWEB)

Osteonecrosis (ON) of the hip joint remains an unsolved therapeutical problem. Diagnosis of ON of the hip has been improved by the technical progress of imaging modalities and better understanding pathomorphology. Over a long period only plain radiographs have been available. Scintigraphy and computed tomography contributed to differential diagnosis and early detection of bone necrosis. Diagnosis in an early reversible stage is of importance. Understanding of pathophysiology, early diagnosis and therapeutical approach has been significantly improved by MR imaging. Using the ARCO system all imaging modalities and their diagnostic viability are described in the five ARCO stages. At the end a diagnostic algorithm will be proposed. (orig.) [German] Die Osteonekrose des Hueftgelenks (ON) stellt noch immer ein nicht geloestes therapeutisches Problem dar. Die diagnostischen Moeglichkeiten bei der ON wurden in den letzten Jahren durch technische Fortschritte bei den bildgebenden Verfahren und ...

2002-06-01

163

Optimising the flow characteristic of a coke-oven flue-gas valve by means of Computational Fluid Dynamics (CFD); Stroemungsoptimierung eines Abgasventils von Koksoefen durch Computational Fluid Dynamics (CFD)  

Energy Technology Data Exchange (ETDEWEB)

In coke-oven operations flue-gas valves are used to switch the regenerator function from rich gas firing to lean gas firing. Compared with the simple geometry of the other parts of the flow path, which comprise flues and regenerators, the narrow and winding passages of the flue-gas valves give rise to relatively high losses in pressure. Without the construction of high (and therefore expensive) chimneys, this means that operating problems may well arise due the inadequate suction capacity. The project focused on the theoretical and experimental analysis of a coke-oven flue-gas valve. The primary aim was to reduce the pressure drop through the valve without modifying its external geomerty. The internal flow characteristics created by different valve geometries under a variety of operating conditions were simulated using the commercial CFD code Fluent/UNS, which provided velocity and pressure distributions. A half-scale model valve was constructed in order to characterise the internal ...

1999-06-01

164

Nuclear power and target-oriented CO{sub 2} reduction strategies; Kernenergie und zielorientierte CO{sub 2}-Minderungsstrategie  

Energy Technology Data Exchange (ETDEWEB)

Compared to the reference year of 1990, CO{sub 2} emissions of the Federal Republic of Germany have been curbed by about 12%, primarily as a result of industrial backfitting and pollution abatement measures accomplished in the industrial infrastructure of the new Federal Laender of Germany. Federal Government policy sticks to the previous commitment, to reduce carbon dioxide emissions by 25% by the year 2005. Current forecasts and scenarios of future greenhouse gas emissions show that only immediate adherence to a very stringent reduction policy might ensure that this ambitious goal will be achieved. In this context, any change of the baseline data and scenarios hitherto used for progonostic assessments is a crucial factor, so that the article here discusses the impacts of a change in the nuclear generation scenario, as recently ventilated by the German Federal Government, and expected effects on public power supply. (orig./CB) [Deutsch] Ausgehend von dem Bezugsjahr 1990 sind die ...

1999-01-01

165

New placement of TIPS during pregnancy for recurring esophageal variceal bleeding: Estimation of fetal radiation exposure; TIPS-Neuanlage in der Schwangerschaft bei rezidivierender Oesophagusvarizenblutung - Abschaetzung der fetalen Strahlenexposition  

Energy Technology Data Exchange (ETDEWEB)

Recurrent variceal bleeding due to liver cirrhosis led to treatment with a transjugular intrahepatic portosystemic shunt (TIPS) in a pregnant woman at 20 weeks` gestation. Fetal radiation exposure was estimated to be less than 10 mSv. The use of a graduated catheter allowed measurement of field size and reliable determination of the patient`s entrance dose. Radiation exposure of an approximated fetal dosage of 5.2 mSv did not justify abortion for medical reasons. Therefore, TIPS procedure is not generally contraindicated during pregnancy itself. TIPS placement may be a therapeutic option related to the severity of the underlying maternal disease, after radiation exposure of the fetus has been estimated. (orig.) [Deutsch] Bei rezidivierender Oesophagusvarizenblutung auf dem Boden einer Leberzirrhose wurde bei bestehender Schwangerschaft der 20. Woche ein transjugulaerer portosystemischer Stent-Shunt (TIPS) neu angelegt. Praeinterventionell wurde die zu erwartende ...

1998-10-01

166

National nuclear energy policy and Community law. Germany`s international commitments due to the EURATOM treaty and membership in the EC and their possible effects on a national policy for abandonment of spent fuel reprocessing and a phase-out of nuclear power; Nationale Kernenergiepolitik und Gemeinschaftsrecht. Die Bindungen des Euratom- und des EG-Vertrages fuer einen Verzicht auf die Wiederaufarbeitung und einen Ausstieg aus der wirtschaftlichen Nutzung der Kernenergie  

Energy Technology Data Exchange (ETDEWEB)

The spent fuel management concept of direct ultimate disposal is compatible in its fundamental features with the law of the European Community. This applies to a national law prohibiting spent fuel reprocessing and the handling of plutonium in Germany, imposing restrictions on exporting spent fuel assemblies and importing plutonium and reprocessing remnants, and on power plant operators to employ reprocessing services abroad. Also, a nuclear power phase-out decided by the German government would in principle not mean a breach of the EURATOM treaty. (orig./HP) [Deutsch] Als Alternative zur geltenden Rechtslage werden im Deutschen Rundestag Aenderungen vorgeschlagen, die das Entsorgungskonzept der direkten Endlagerung - d.h. ein Verbot der Wiederaufarbeitung von Brennelementen aus deutschen Kernkraftwerken auch im europaeischen Ausland - vorschreiben und einen ``Ausstieg`` aus der Kernenergienutzung anordnen. Vor dem Hintergrund einer Analyse der tatsaechlichen ...

1995-08-01

167

Multi-rotor-stations, a new concept for large-scale wind power stations; Multi-Rotor-Konstruktionen. Ein neues Konzept fuer grosse Windkraftanlagen  

Energy Technology Data Exchange (ETDEWEB)

As an alternative to the usual way of installing wind machines in extended windfarms new concepts are being developed. Several wind turbines are affixed to one support structure and can be aligned together. Drafts of steel constructions developed by students in three diploma theses are presented. The attempt to transform existing design standards requires extensive discussion of possible influence scenarios. Several concepts regarding structure and safety elements are described and evaluated. The design of the support structure is to be seen as a first step to the practicability of the whole concept. A preliminary mass calculation and a specification of further cost factors facilitates the comparison to conventional wind power stations. (orig.) [Deutsch] Als Alternative zur ueblichen Praxis, Windenergieanlagen in Form grossflaechiger Windparks zu bauen, werden Konzepte entwickelt, bei denen mehrere Konverter an einem Tragwerk angeordnet und gemeinsam in den Wind ausgerichtet werden. ...

1996-06-01

168

Monitoring of a passive house school building; Erkenntnisse ueber Lueftung und Energieverbrauch sowie Bodenplattendaemmung aus Monitoring-Untersuchungen an einem Passivhaus-Schulgebaeude  

Energy Technology Data Exchange (ETDEWEB)

More than two and a half years of monitoring of a passive house school and day-care centre in Frankfurt a. M. show comfortable indoor climate and good air quality. The space heat consumption is low and shows savings of approximately 90 % as compared to average existing schools. Excellent performance was also achieved in terms of primary energy. The results of further analyses of the efficient ventilation system with heat recovery, the perimeter insulation as an alternative to floor slab insulation and the influence of the air change due to the entrance door are presented. (Abstract Copyright [2008], Wiley Periodicals, Inc.) [German] Ueber zweieinhalb Jahre Monitoring einer Passivhaus-Schule und Kindertagesstaette (KiTa) in Frankfurt a.M. zeigt behagliche raumklimatische Bedingungen bei guten Luftqualitaeten. Die Heizwaermeverbrauchswerte liegen wie erwartet niedrig und zeigen Einsparungen um 90 % gegenueber dem Durchschnitt im Bestand. Auch primaerenergetisch ...

2008-02-15

169

Lacrimal gland masses on CT and MRI: a report of four cases; Raumforderungen der Traenendruese in CT und MRT am Beispiel von vier Faellen  

Energy Technology Data Exchange (ETDEWEB)

In an extended case report, we discuss four cases with masses in the lacrimal fossa representing the most important entities in this region (lymphoma, pleomorphadenoma, inflammatory pseudotumor, and malignant epithelial tumor). The different indications for CT and MRI are explained. For the differential diagnosis of lacrimal gland lesions, the following imaging parameters are important: The shape of the lacrimal gland, the inner structure, the degree of contrast enhancement, and the surrounding bony structures. In the evaluation of the expansion of lacrimal gland lesions, CT in thin slices with multiplanar reconstructions is equal to MRI. However, the contrast-enhancement of lacrimal glands is better evaluated with MRI than with CT. The bony structures are better visualized on CT than on MRI. (orig.) [Deutsch] In einem erweiterten Fallbericht wird ueber die vier grossen Entitaeten bei Traenendruesenraumforderungen berichtet (Lymphom, pleomorphes Adenom, entzuendlicher Pseudotumor und ...

1995-11-01

170

Investigations on process design and fuel substitution in a cokeless, natural-gas-fuelled cupola furnace; Untersuchung zur Prozessgestaltung und Brennstoffsubstitution an einem kokslosen erdgasbefeuerten Kupolofen (KLKO)  

Energy Technology Data Exchange (ETDEWEB)

A process model is presented and used for identifying options for controlling the cupola furnace process and for investigating natural gas substitutes. Fuel substitution will affect temperature curves (i.e. tapping temperatures and melting capacity), outlet temperatures and gas mass flow out of the preheating zone. The contribution presents several process variations to overcome these problems and compares them with the natural gas process. [German] Mit dem Prozessmodell werden zunaechst Moeglichkeiten der Steuerung von Abstichtemperatur und Schmelzleistung, insbesondere unter Beruecksichtigung der Schrottqualitaet (spezifische Oberflaeche a{sub G}), untersucht. Es wird gezeigt, dass das Prozessmodell die Ergebnisse aus der Praxis wiedergibt. Daran anschliessend wird mit dem Prozessmodell die Substitution von Erdgas durch minderwertige Gase untersucht (Brennstoffsubstitution, Ressourcenschonung). Durch die Brennstoffsubstitution veraendern sich die Temperaturverlaeufe und damit auch ...

2001-07-01

171

Ingestion dose for molybdenum: dependence on the administration form; Ingestionsdosis fuer Molybdaen: Abhaengigkeit von der verabreichten Form  

Energy Technology Data Exchange (ETDEWEB)

Molybdenum is an essential element for living organisms. Moreover its radionuclides may represent an incorporation risk for members of the public and/or radiation workers after a nuclear accident or a release of radioactive materials. However, only few reliable data on Mo biokinetics in humans were available. The results of recent tracer kinetic investigations with stable isotopes have shown several differences from the ICRP data with regard to the processes of intestinal absorption and of excretion. As a consequence, the dose coefficients calculated with a revised biokinetic model deviate from the ICRP estimates. By ingestion of {sup 99}Mo radionuclides with solid food, for example, the dose to the colon may be higher of a factor up to 1 order of magnitude, due to the fraction of non-absorbed material which traverses the gastro-intestinal tract. (orig.) [Deutsch] Molybdaen ist einerseits ein fuer Lebewesen essentielles Spurenelement, andererseits koennen radioaktive Mo-Isotope im ...

1998-12-31

172

HyTra: Mobile hydrogen supply. Flexible and safe; HyTra - Mobile Wasserstoffversorgung. Flexibel und sicher  

Energy Technology Data Exchange (ETDEWEB)

In order for fuel cells to be successful, a full-scale hydrogen infastructure is required. The HyTra concept is presented here (HYdrogen TRAnsform, Transfer and TRAnsport) involves combined production, storage and supply of hydrogen in a transportable trailer, i.e. it is both a hydrogen production unit and a mobile filling station. The trailer can be transported to the selected site, where it will produce gaseous hydrogen from electricity and water by electrolysis. A compressor pumps the gas into an internal pressure tank and compresses it to filling pressure. Filling takes place by the overflow principle via a flexible high-pressure line with a standardised H{sub 2} filling unit. (orig.) [German] Um die Marktdurchdringung der Brennstoffzellentechnik gewaehrleisten zu koennen, muss eine flaechendeckende Wasserstoffinfrastruktur aufgebaut werden. Das neue HyTra-Konzept (HYdrogen TRAnsform, TRAnsfer and TRAnsport) beruht auf der Kombination von Wasserstoff-Erzeugung, -Speicherung und ...

2006-11-15

173

High-End CT for clinical and scientific applications; High-End-CT im klinischen und wissenschaftlichen Einsatz  

Energy Technology Data Exchange (ETDEWEB)

The enhancements described of high-performance CT systems of latest design have again confirmed the importance of CT systems for acute and selective diagnostic imaging. Higher availability, shorter exposure times, and better applicability and handling for examination of poly-traumata patients or patients of intensive care departments are some of the advantages achieved with CT systems which demonstrate CT system efficiency in addition to MRI, which for specific examinations will remain the modality of first choice for diagnostic evaluation. The Tomoscan Av-E presented here was able to answer all relevant diagnostic questions appearing in routine diagnostics and scientific work. For patients, examinations using the spiral CT technique also offers significant advantages. (orig./CB) [Deutsch] Durch die dargestellten Verbesserungen bei Hochleistungs-CT-Systemen neuester Bauart wurde die Bedeutung der CT fuer die akute und selektive Diagnostik erneut bestaetigt. Bessere Verfuegbarkeit, ...

1997-12-01

174

Experiences with the operation of a battery energy storage plant for frequency and output control and provision of immediate reserve capacities; Erfahrungen mit Betrieb einer Batteriespeicheranlage zur Frequenz-Leistungs-Regelung und Bereitstellung von Sofortreserveleistung  

Energy Technology Data Exchange (ETDEWEB)

In 1986, following comprehensive preliminary studies, a 17 MW battery energy storage plant was set up in the insular power supply system of Berlin (West) for the purpose of frequency and output control and provision of immediate reserve capacities. The present paper reports on the initial task, and the dimensioning and construction of this large-scale demonstration as well as the costs entailed in this. It also relates the experiences gained with the operation of the battery energy storage plant in its function as a fast-responding control unit and gives an account of its economic efficiency. Recent studies on the economic efficiency of the plant in conditions as they exist in the present interconnected power supply system are presented. Finally the author reports on the experiences gained with individual plant components, i.e., battery, battery periphery, and power converter and quantifies the cost of plant operation, maintenance, and servicing. (orig./HW) [Deutsch] Im Inselnetz von ...

1996-12-31

175

Experience with the austenite materials 1.4541 and 1.4550 in German boiling water reactors; Erfahrungen mit den austenitischen Werkstoffen 1.4541 und 1.4550 in deutschen Siedewasserreaktoren  

Energy Technology Data Exchange (ETDEWEB)

Stabilized austenitic steels can suffer intercrystalline stress corrosion cracking under BWR water conditions. This experience of the last three years, which is important for German nuclear power station technology, has resulted from the discovery of cracks, which were detected in pipework made from titanium-stabilized 1.4541 charged with hot reactor water in six boiling water reactors and in core components made from niobium-stabilized 1.4550 of one BWR plant. Remedies to the pipework have been found by applying optimized materials and fabrication procedures and also by improving water chemistry conditions. (orig.) [Deutsch] Stabilisierte austenitische Staehle koennen unter SWR-Reaktorwasser-Bedingungen interkristalline Spannungsrisskorrosion (IKSpRK) erleiden. Diese fuer die deutsche Kernkraftwerkstechnik bedeutsame Erfahrung der letzten drei Jahre ergab sich aus Rissbefunden, die in mit heissem Reaktorwasser beaufschlagten Rohrleitungen aus dem Ti-stabilisierten 1.4541 von sechs ...

1996-10-01

176

Effects of ductile particles on the toughness and deformation characteristics of NiAl matrix materials; Einfluss duktiler Teilchen auf die Zaehigkeit und das Verformungsverhalten von NiAl-Matrix-Werkstoffen  

Energy Technology Data Exchange (ETDEWEB)

The intermetallic phase NiAl is a potential material for high-temperature applications; however, its technical application was prevented so far by its high brittleness at room temperature. This problem may be solved by incorporating relatively high-ductility particles into the NiAl matrix. Controlled crack propagation experiments, tensile and pressure tests were carried out in order to analyze the toughness and deformation characteristics of NiAl composite materials containing niobium or molybdenum particles at room temperature and in ambient atmosphere. Both the niobium and the molybdenum particles increase the toughness as compared to the pure NiAl matrix, but no ductilisation was observed in the composite materials investigated. Model experiments in consideration of experimental data suggest, hovewer, that the toughness and ductility of NiAl may be enhanced by optimizing the microstructural and production parameters of the incorporated ductile particles. (orig.) [Deutsch] Die ...

1995-12-31

177

Diagnosis of occipital condyle fractures; Diagnostik von Frakturen der Okzipitalkondylen  

Energy Technology Data Exchange (ETDEWEB)

Following the conventional X-ray diagnosis of the skull and upper cervical spine, CT proved to be the primary diagnostic method after a skull and brain injury: For all 4 cases we succeeded in detecting the occipital condyle fracture and in determing its size and location by reconstructions (coronal, sagittal, 3-D). In the case of complex occompanying injuries like soft tissue hematomas (cerebral, in the spinal cord, and the soft tissue of the neck) or for the detection of brain stem contusion, MRT had significant advantages. MRT can offer a higher image quality in soft tissue, especially in the spinal cord and the brain. (orig.) [Deutsch] Im Anschluss an die konventionelle Roentgendiagnostik des Schaedels und der Halswirbelsaeule, erwies sich die Computertomographie als primaer einzusetzendes diagnostisches Verfahren, nach erlittenem Schaedel-Hirn-Trauma. In allen Faellen gelang der exakte Frakturnachweis an den Okzipitalkondylen, die Bestimmung des Frakturausmasses und die genaue ...

1995-01-01

178

Development of methodics for the characterization of the composition of the ion-collision-induced secondary-particle flux by comparison of the yield contributions of photoinduced ion formation processes; Entwicklung einer Methodik zur Charakterisierung der Zusammensetzung des ionenbeschussinduzierten Sekundaerteilchenflusses durch Vergleich der Ausbeuteanteile photoinduzierter Ionenbildungsprozesse  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work was to develop a method to distinguish between different ion formation processes and to determine the influence of these processes on the total number of detected monatomic ions of a certain element. A vector/matrix-formalism was developed, which describes the physical processes of sputtering, ion formation, mass separation and detection in laser-SNMS. In the framework of the method developed, based on this theoretic formalism, changes in the secondary flux contribution of the respective element were observed by comparing the detected monatomic ion yield obtained in specifically aligned (SIMS and) laser-SNMS experiments. The yields resulting from these experiments were used to calculate characteristic numbers to compare the flux composition from different surfaces. The potential of the method was demonstrated for the elements boron, iron and gadolinium by investigating the changes in the flux composition of secondary particles sputtered from metallic surfaces, as a ...

2008-10-13

179

Crack resistance in ceramic fibre compound materials; Risswiderstand in keramischen Faserverbundwerkstoffen  

Energy Technology Data Exchange (ETDEWEB)

The fibre reinforcement of ceramic materials is used above all to improve the toughness and tolerance of damage, compared to unreinforced monolithic ceramics. This improvement is made possibly by the bridging effect of the cracks by the fibres in crack propagation in the matrix. In this work, the crack bridging effect of the fibres is included in a bridge stress equation, in which a clear relationship between bridge stress and crack opening is determined. The most important step for deriving the bridge stress law was determining the probability of failure of a fibre for a given axial stress curve. One relied on the micromechanical analysis of Hutchinson and Jensen here, by which the boundary conditions in multi-fibre materials can be included and realistic assumptions can be made for the load transfer mechanisms in the fibre/matrix boundary surface. (orig./MM) [Deutsch] Die Faserverstaerkung keramischer Werkstoffe dient vor allem zur Verbesserung der Zaehigkeit und Schadenstoleranz ...

1995-03-01

180

Cell model of nonisothermal gas absorption in gas-liquid bubbly media  

Energy Technology Data Exchange (ETDEWEB)

A model for combined mass and heat transfer during nonisothermal gas absorption in a two-phase gas- liquid bubbly medium with a high gas content and/or large times of gas-liquid contact is suggested. Diffusion and thermal interactions between bubbles is taken into account in the approximation of a cellular model of a bubbly medium whereby a bubbly medium is viewed as a periodic structure consisting of identical spherical cells with periodic boundary conditions at a cell boundary. Distribution of concentration of dissolved gas, temperature distribution in liquid and coefficients of mass and heat transfer during nonisothermal absorption of a soluble pure gas from a bubble by liquid are determined. In the limiting case of absorption without heat release the derived formulas recover the expressions for isothermal absorption. (orig.). With 1 fig., 1 tab. [Deutsch] Es wird ein Modell vorgestellt, das den kombinierten Waerme- und Stoffaustausch waehrend der nichtisothermen Gasabsorption in ...

1996-06-01

181

BMBF. The biotechnology 2000 project. Annual report 1994; BMBF. Programm Biotechnologie 2000. Jahresbericht 1994  

Energy Technology Data Exchange (ETDEWEB)

The `biotechnology 2000` project is supervised by the project sponsor `biology, energy, ecology` at Forschungszentrum Juelich on behalf of the Federal Ministry for Research and Technology. The project activities cover the development of techniques and methods, cell biology, gene structure and gene regulation, photosynthetic production processes, biological hydrogen production, synthetic biology, protein design, neurobiological research, biosystems, plant breeding, phytomedicine and plant protection, the biology of waste disposal methods, research into methods which replace animal experiments, biological safety research, technology risk assessment, and ethical aspects. A general survey introduces the promoted projects, and standardized data sheets briefly introduce the individual activities. The appendix gives the project indices, the indices of joint projects, a list of the supported companies and institutions, and the project sponsor flowsheet. (orig.) [Deutsch] Das Programm ...

1995-11-01

182

Agricultural ecosystem modelling. The basis for assessing the impact of possible land-use and climate changes. Final report; Agrooekosystemmodellierung. Grundlage fuer die Abschaetzung von Auswirkungen moeglicher Landnutzungs- und Klimaaenderungen. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of the BMBF-sponsored project Fundamentals and models for assessing the effect of climate changes on soil, plant development and the crops of an economically significant range of farm products. Its aim was to study, by means of the results obtained for winter wheat, the dependence of plant growth on temperature, radiation and water as well as nutrient supply for other economically important crop types. Building on this, process-oriented, climate-sensitive agricultural ecosystem models for winter rye, winter barley, sugar-beet and winter intercrops were developed, verified and, in some sites, validated. First scenario calculations served to demonstrate the climate sensitivity of these models. (orig./KW) [Deutsch] Im vorliegenden Bericht werden die Ergebnisse des BMBF - Vorhabens `Grundlagen und Modelle zur Abschaetzung von Klimaaenderungen auf den Boden, die Pflanzenentwicklung sowie den verwertbaren Ernteertrag einer wirtschaftlich ...

1995-12-31

183

Vessel wall MRI of the thoracic aorta: correlation to histology and transesophageal ultrasound. Preliminary results  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To visualise the vessel wall of the descending thoracic aorta using magnetic resonance imaging. To evaluate the diagnostic potential of tailored T{sub 1}-weighted sequences with contrast enhancement to assess systemic atherosclerotic disease. Methods: This study was performed on a clinical 1.5 Tesla scanner using a gradient strength of 30 mT/m and the phased array spine coil. A cadaver was examined to optimise a magnetic resonance imaging (MRI) protocol to evaluate atherosclerotic aortic wall disease. The acquired MR images were compared to gross specimens and histology. Subsequently seven patients who had undergone transesophageal ultrasound (TEU) with detailed assessment of the descending thoracic aorta were examined with MRI. The optimised protocol included untriggered and fat suppressed T{sub 2}-weighted turbo spin echo sequences and ECG-triggered and fat suppressed T{sub 1}-weighted spin echo sequences before and after iv administration of Gd-DTPA. Findings of the MR ...

2002-05-01

184

Carbomolybdates(III): On Pr{sub 2}[Mo{sub 2}C{sub 3}] and structural relations to Er{sub 2}Mo{sub 2}C{sub 3}; Carbomolybdate(III): Zur Kenntnis von Pr{sub 2}[Mo{sub 2}C{sub 3}] sowie Strukturbeziehungen zu Er{sub 2}Mo{sub 2}C{sub 3}  

Energy Technology Data Exchange (ETDEWEB)

Pr{sub 2}[Mo{sub 2}C{sub 3}] was obtained by arc melting of the elements followed by annealing at 1500 C in arc welded and sealed Mo-ampoules. The compound was characterised by chemical analyses, X-ray diffraction and metallography. The crystal structure (monoclinic, P2{sub 1}/c, Z = 4, a = 597.99(10) pm, b = 665.15(11) pm, c = 1185.60(19) pm and {beta} = 111.631(5) ) represents a new structure type containing a three dimensional polyanion {sub {infinity}}{sup 3}[(Mo{sub 2}C{sub 3}){sup 6-}] with Molybdenum(III) in a distorted tetrahedral coordination by carbo-ligands. Tetrameric building-blocks, Mo{sub 4}C{sub 10}, of edge sharing MoC{sub 4}-tetrahedra are arranged to form layers running parallel to (100). The layers are interconnected along [100] by sharing common apices of the MoC{sub 4} tetrahedra. The coordination polyhedra around praseodymium represent distorted (PrC{sub 5})-arrangements (mono capped tetrahedra and square pyramids). The metal atoms together form a distorted motif ...

2004-11-01

185

Treatment of peripheral aneurysms by dacron-covered nitinol stents; Behandlung arterieller Aneurysmen der Becken-Bein-Gefaesse mittels Dacron-ummantelter Nitinol-Stents  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To evaluate the success rates of the implantation of stent grafts in the treatment of peripheral aneurysms. Materials and methods: in 13 patients with 15 aneurysms at the common iliac artery (n = 6), external iliac artery (n = 1), hypogastric artery (n = 2), femoral artery (n = 2) or popliteal artery (n = 4), implantation of dacron-covered nitinol stents was performed. The patients were followed up for three to 20 months (mean, 8.8 months) with intravenous digital subtraction angiography, CT or colour-coded Doppler sonography. Results: In all cases, the aneurysm was successfully occluded after stent implantation. In one case with a popliteal aneurysm, kinking of the vessel caused thrombosis of the stent. The stent was successfully reopened. The aneurysm however, had to be surgically treated 9 months later. The primary and secondary patency rates at 6 months were 93% and 100%, respectively. Conclusion: The method described might be an alternative therapy to surgery. There are ...

1998-03-01

186

Thermomechanical fatigue of ODS superalloys; Thermomechanische Ermuedung von ODS-Superlegierungen  

Energy Technology Data Exchange (ETDEWEB)

The ODS superalloys MA 6000 and MA 760 were investigated with regard to their behaviour under non-isothermal fatigue stress. For this purpose, strain-controlled thermomechanical and bithermal experiments with different phase relationships between strain and temperature were carried out on the one hand; on the other hand, the deformation behaviour under thermomechanical stress was modelled on the basis of isothermal cyclic creep data. The fatigue experiments show that a diamond-shaped cycle derived from the stress pattern of a turbine blade is clearly less critical than in-phase and out-of-phase cycles. The life of the diamond-shaped cycle is determined by oxidation-induced crack initiation and propagation and can be predicted easily with a suitable damage model. Important damage parameters required by the model can be obtained by the less complicated bithermal fatigue tests. Modelling of the TMF hystereses suggests that cyclic, non-isothermal deformaltion is determined mainly by ...

1995-07-01

187

Studies of bearings to be used in high-temperature reactor plants. Final report; Lageruntersuchungen fuer Anwendungen in Hochtemperatur-Reaktor-Anlagen. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

Several components of high-temperature reactor units have roller bearings in order to carry out their motions without much friction. The use of such bearings poses friction and wear problems which cannot be mastered by commercial roller bearing technology. Possible improvements of coating, cage design and bearing materials as well as of their parameters were registered and studied. The service life of dry lubricated bearings was considerably improved. With a radial or axial load on the bearing of {>=} 10% of the static load, {approx_equal} 20x10{sup 6} rolling motions/actuations can be performed. The connections between surface compression and wear were determined, and optimum conditions for the transfer of lubricants from the cage onto the bearing race were worked out. Coating of corrosion-resistant roller bearing steels with the HRB-M{sub 0}S{sub 2} running-in coating could be proved. New cage designs and materials were tested with positive results. Alternative coatings (thin ...

1991-09-13

188

Stress intensity factors of cracks in material compounds near boundary surfaces with mechanical and thermal loading; Spannungsintensitaetsfaktoren von Rissen in Stoffverbunden in der Naehe von Grenzflaechen bei mechanischer und thermischer Belastung  

Energy Technology Data Exchange (ETDEWEB)

A singular stress field can occur at the edge of the joint plane in a thermally or mechanically loaded material compound. This stress field was calculated analytically and was compared with the results from the finite element method. If one of the two partners consists of ceramic material, unstable crack spread starting from faults in this strongly stressed area can lead to failure. In linear elastic material, the behaviour of a crack is clearly described by the stress intensity factors. These can be calculated for a known stress distribution in the uncracked structure by the method of the weight function. The corresponding weight functions for surface cracks parallel to the boundary surface were determined with the aid of suitable reference load cases. The effect of the position of the crack in the compound and the elastic constants of the compound are discussed. For examples, the stress intensity factors for cracks in a thermally stressed material compound were determined by the ...

1995-03-01

189

Start of the SAPIERR project of regional final storage of radioactive waste in the European Union; Auftakt des SAPIERR-Projekts ueber eine regionale Endlagerung radioaktiver Abfaelle in der Europaeischen Union  

Energy Technology Data Exchange (ETDEWEB)

The first working meeting of the SAPIERR project about regional final storage of radioactive waste in the European Union was held in Piestany, Slovak Republic, on February 19 and 20, 2004. SAPIERR stands for Support Action: Pilot Initiative for European Regional Repositories. This is an independent study supported financially by the European Union within the 6th Research Framework Program. The background to the project is the debate about the feasibility of regional repositories for radioactive waste in the European Union, which has come up again especially with a view to the new accession countries and the draft of a waste management directive within the framework of the Nuclear Package. The results of the SAPIERR Project will be presented in Brussels at a concluding international seminar, most probably in October 2005. The seminar will be open not only to the participating countries but also to other interested European and non-European states. (orig.) [German] Am 19. und 20. Februar ...

2004-06-01

190

Processing and physical utilisation of waste materials relevant to iron and steel manufacture; Aufarbeitung und stoffliche Nutzung eisen- und stahlrelevanter Abfallstoffe  

Energy Technology Data Exchange (ETDEWEB)

A part of the waste materials arising in iron and steel manufacture is utilised physically, either internally for the recovery of iron or externally for the production of cement and nonferrous metals. Most of these materials can be used without prior processing. Iron and steel-relevant waste materials which at present are still landfilled or disposed of as hazardous wastes are not immediately suitable for physical recycling as secondary raw material. These waste materials have to be processed without exception before they can be used again in the existing steel and iron manufacturing plants. The results of the authors` own studies have clearly shown that the cupola furnace is suited for the use of a wide variety of waste materials. [Deutsch] Ein Teil der bei der Eisen- und Stahlerzeugung anfallenden Abfallstoffe werden entweder intern zur Rueckgewinnung des Eisens oder extern in der Zement- bzw. Nichteisenmetallgewinnung stofflich verwertet. Dabei handelt es sich ueberwiegend um ...

1998-09-01

191

New procedures. Comprehensive staging of lung cancer by MRI; Neue Verfahren. Umfassendes Staging des Lungenkarzinoms mit der MRT  

Energy Technology Data Exchange (ETDEWEB)

Lung cancer staging according to the TNM system is based on morphological assessment of the primary cancer, lymph nodes and metastases. All aspects of this important oncological classification are measurable with MRI. Pulmonary nodules can be detected at the clinically relevant size of 4-5 mm in diameter. The extent of mediastinal, hilar and supraclavicular lymph node affection can be assessed at the same time. The predominant metastatic spread to the adrenal glands and spine can be detected in coronal orientation during dedicated MRI of the lungs. Search focused whole body MRI completes the staging. Various additional MR imaging techniques provide further functional and clinically relevant information during a single examination. In the oncological context the most important techniques are imaging of perfusion and tumor motion. Functional MRI of the lungs complements the pure staging and improves surgical approaches and radiotherapy planning. (orig.) [German] Das Staging des ...

2010-08-15

192

Modified nickel based standard brazing filler metals for units under corrosive loads; Modifizierte Nickelbasisstandardlote fuer korrosiv belastete Bauteile  

Energy Technology Data Exchange (ETDEWEB)

Nickel-based alloys are presently used as brazing filler metals for components which undergo mechanical stress in corrosive conditions, f. e. heat exchangers. When soldering chrome containing steel parts with nickel based brazing filler metals additionally containing boron and silicon a reaction of chrome and boron can occur. This evolution of chromium borides, depositing on grain boundaries, causes a lack of chrome in the steel part. A drop of the chrome content in the parts below 13 % leads to a loss of corrosion resistance. It is possible to change the microstructure of brazing joints by modification with chromium and molybdenum. Continuous brittle phases could be successfully avoided with this modification. Furthermore it could be shown that the choice of additives, the heating respectively cooling rate and the brazing temperature have important influence on the microstructure evolution and therefore on the mechanical and corrosive properties of joints. (Abstract Copyright [2008], ...

2008-01-15

193

Medium voltage network planning based on probabilistic reliability evaluation including the insurance system  

Energy Technology Data Exchange (ETDEWEB)

In comparison to deterministic criteria, probabilistic reliability indices like interruption frequency and unavailability give a more differentiated insight into reliability in an electrical energy network. One possibility for network planning based on these indices is the definition of limits for customer nodes, another is the monetarisation of reliability in terms of interruption costs. Because of numerous disadvantages, interruption cost methods could not up to now win broad recognition in network planning in Western Europe. A more recent method for the monetarisation of reliability circumventing most of these disadvantages is the insurance system. In this system the customer selects a tariff class in an insurance system, and the utility reimburses its customers in the case of an interruption. In its first section, the paper describes a method for the flexible and realistic optimisation of MV networks. This method based on Genetic optimisation is able to integrate probabilistic ...

1997-07-01

194

Measurement of level lifetimes in the ps range and model interpretations for neutron-rich A {approx_equal} 100 nuclei  

Energy Technology Data Exchange (ETDEWEB)

The nuclear structure of A {proportional_to} 100 nuclei has been studied in the frame of this thesis with a recently developed {beta} - {gamma} - {gamma} triple coincidence fast timing technique and different models such as shell model, hydrodynamic model, Nilsson and particle-rotor models. This technique which allows the measurement of the level lifetimes in the ps range has been applied at JOSEF at the research reactor DIDO of KFA Juelich in studes of the short-lived neutron-rich nuclei in the A {approx_equal} 100 region. Lifetimes of level in {sup 96},{sup 98},{sup 100} ZR, {sup 99},{sup 101}-{sup 104} Nb, {sup 100}-{sup 105} Mo have been measured, which are in many cases completely new, and otherwise more precise than previously published data. From the lifetimes of the members of rotational bands, the size of the nuclear deformations has been deduced. (orig./HSI). [Deutsch] Im Rahmen dieser Doktorarbeit wurde die Kernstruktur der A {proportional_to} 100 Kerne untersucht. Dazu ...

1992-08-01

195

MRI in postoperative assessment of univentricular heart disease: correlation with echocardiography and angiography; MRT in der postoperativen Diagnostik bei funktionell univentrikulaerem Herz: Korrelation zu Echokardiographie und Kardangiographie  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To determine the value of MRI in the postoperativ evaluation of a singular ventricle compared to echocardiography and cardiac catheterization. Materials and methods: Thirty-one patients (range: 6 months to 30 years) with a functional single ventricle following palliative corrective operations. Five patients had a Blalock-Taussig-Shunt, 8 patients a Glenn-Anastomosis and 18 a cavopulmonary shunt (6 with classic Fontan-Circulation, 12 with modified cavopulmonary anastomosis). The results in terms of postoperative morphologic changes were compared to percutaneous echocardiography (31/31) and cardiac catheterization (6/31). Results: Echocardiography, which was performed on all patients, could not visualize the entire length of the tunnel, the Glenn-Anastomosis or the central pulmonary arteries in 70% of the patients due to an inadequate acoustic window. MRI was able to show the entire tunnel in 11/12 patients and the central pulmonary arteries in 30/31 patients. The exact anatomy ...

2002-12-01

196

Investigations on the braking safety of utility vehicles with retarders; Untersuchungen zur Bremssicherheit von Nutzfahrzeugen mit Retardern  

Energy Technology Data Exchange (ETDEWEB)

When the use of retarders in utility vehicles increased in the middle of the 80s, the Forschungsvereinigung Automobiltechnik (FAT) commissioned a study on the safety aspect of this braking technology in trucks. Retarders are wear-free permanent brakes that are fitted in the drive transmission system of utility vehicles, thereby generating braking forces only at the wheels of the live shaft. The question of the possible overbraking of the live shafts was just as well investigated as the interaction between the retarder and service brake in so-called integrated braking systems, and both under conditions of low adhesion as well as in the border area of the dynamics of vehicle movement. This subject met with considerable joint interest on the part of the motor vehicle industry as well as of manufacturers of towed vehicles and unit sets. FAT, therefore, commissioned the Institut fuer Kraftfahrwesen of the University of Hannover to carry out a three-phase research project on the braking ...

1996-12-31

197

Investigation of respiratory-dependent movements of pulmonary space-occupying lesions with MRI; Untersuchung der atemabhaengigen Bewegungen pulmonaler Raumforderungen mit der MRT  

Energy Technology Data Exchange (ETDEWEB)

Parallel imaging and echo sharing techniques have markedly reduced the acquisition times for MRI of large volumes. Dynamic 2 and 3-dimensional data sets of the chest with high temporal resolution (up to 10 images/s with single slice and 2 volume/s) allow an analysis of respiratory motion of the lungs and tumors. Time-resolved 2D series in preselected planes can be used to observe respiratory motion during free breathing or after respiratory commands, e.g. to exclude chest wall invasion by a tumor or for diagnosing impairment of respiratory mechanics. Time-resolved 3D-series (4D-MRI) allow monitoring of the spatial displacement of the lungs and tumors as a whole volume. Present limitations such as an overestimation of tumor size and an underestimation of displacement due to a limited temporal resolution are expected to be overcome with further technical developments. However, 4D-MRI already appears to be the appropriate tool to select patients for motion-adapted radiotherapy. In ...

2009-08-15

198

Influence of tempering on microstructure and hardness of high-temperature 9%Cr-steels; Einfluss des Anlassens auf Gefuege und Haerte warmfester 9%Cr-Staehle  

Energy Technology Data Exchange (ETDEWEB)

The influences of temperature and duration of tempering on hardness and microstructure were investigated at high-temperature martensitic and low-carbon steels with 9% chrome and the further alloying elements molybdenium, vanadium, niobium and partially tungsten. After austenitizing and subsequent air cooling the steels were tempered at temperatures below, at and above Ac{sub 1b} for different times and finally a hardness test was performed. Making use of the temperature dependence of the hardness tempering diagrams were constructed and the Hollomon-Jaffe-Parameter on the three steels was determined within its application limits. Micrographs of the structure shows the formation of the carbides and the martensite. At tempering temperatures below Ac{sub 1b} a decrease of hardness occurs, above Ac{sub 1b}, a hardness rise due to the partial austenitizing was obtained. While hardening below Ac{sub 1b}, the tempering quality increases from P 91, NF 616 to E 911. (orig.) [Deutsch] An ...

1999-06-01

199

Impacts of grain structure and texture on the high-temperature fatigue in ODS superalloys; Einfluss der Kornstruktur und der Textur auf die Hochtemperaturermuedung von ODS-Superlegierungen  

Energy Technology Data Exchange (ETDEWEB)

The study examines the isothermal fatigue properties of novel ODS iron-base or nickel-base superalloys at temperatures of 850 C and 1050 C. The materials are different in grain structure and texture, so that particularly the effects of grain structures and textures can be studied. In order to also perform examinations of creep-fatigue interactions, various load cycles are applied. It is shown that the LCF-affected life of the grain structures of both alloy types is determined by the elastic modulus. The cyclic lifetimes determined by the conventional Manson-Coffin method for both alloy types exhibit differences of up to two orders of magnitude. Using the product of the total strain range and the elastic modulus, however, will yield precise life predictions. Under conditions of LCF stress only, the grain structure has no effect on the materials` service life, other than in the case of creep-fatigue, but the grain structure has a decisive influence on the damage mechanisms and the course ...

1995-12-31

200

High-frequency microseismicity in the rock salt of the Asse mine around the 945 m level; Hochfrequenz Mikroseismizitaet im Steinsalz der Asse um den 945-m-Bereich  

Energy Technology Data Exchange (ETDEWEB)

3407 events were registrated up to a distance of 300 m during the period from 12.10.1989 to 31.12.1990, of which 385 could be precisely located. Activities were determined in areas surrounding the dam construction traversal drifts and boreholes at the 875 m level, near the large cavern at 975 m depth, in drifts and caverns above the 875 m level and in the vicinity of the rock salt/carnallitite transition zone to the south-east of the 875 m level. Energies and source parameters were calculated by means of spectres. Energy variations range from 10 J to 10{sup -4} J, the source radii from 3.5 m to 0.2 m, the source dislocations from 10{sup -6} m to 10{sup -8} m, and the stress drops from 10{sup 5} Pa to 0.06 10{sup 5} Pa. Magnitude and type of events observed are usual for mines. The microseismic activity provides an insight into the origin as well as changes of stress and rock mechanical material properties. (orig./HP). [Deutsch] Im Zeitraum 12.10.89 - 31.12.90 wurden 3407 Ereignisse bis ...

1991-11-01

201

FLUTAN 2.0. Input specifications  

Energy Technology Data Exchange (ETDEWEB)

FLUTAN is a highly vectorized computer code for 3D fluiddynamic and thermal-hydraulic analyses in Cartesian or cylinder coordinates. It is related to the family of COMMIX codes originally developed at Argonne National Laboratory, USA, and particularly to COMMIX-1A and COMMIX-1B, which were made available to FZK in the frame of cooperation contracts within the fast reactor safety field. FLUTAN 2.0 is an improved version of the FLUTAN code released in 1992. It offers some additional innovations, e.g. the QUICK-LECUSSO-FRAM techniques for reducing numerical diffusion in the k-{epsilon} turbulence model equations; a higher sophisticated wall model for specifying a mass flow outside the surface walls together with its flow path and its associated inlet and outlet flow temperatures; and a revised and upgraded pressure boundary condition to fully include the outlet cells in the solution process of the conservation equations. Last but not least, a so-called visualization option based on VISART ...

1996-05-01

202

Degradation of toluene in a multistage bioreactor unit; Abbau von Toluol in einer zweistufigen Tropfkoerperbioreaktor-(TBR-)Anlage  

Energy Technology Data Exchange (ETDEWEB)

Volatile organic compounds (VOC) are an important group of pollutants with adverse effects on humans and the environment. Primary air pollution abatement measures aim at prevention or reduction of pollutant production in industrial production processes, e.g. by improved processes but also by other methods (closed cycle processes, different process materials, etc.). If these measures have been implemented and emissions are still too high, an off-air purification unit must be installed. Biological purification is the method of choice for low pollutant concentrations. Biological purification processes are based on the activity of microorganisms which are capable of biochemical oxidation of organic and some inorganic gaseous compounds into non-polluting or non-odorous compounds. These processes have the advantage that they work at ambient conditions and therefore remove relatively low pollutant concentrations at low investment and operating cost. Lately, biological filters and washers have ...

1997-05-01

203

Characterization of decarburisation processes during austenitising of the rolling bearing steel 100Cr6. Part 1: Correlation between rim zone properties and carbon concentration profile; Charakterisierung von Randentkohlungsvorgaengen bei der Austenitisierung des Waelzlagerstahls 100Cr6. Teil 1: Korrelation zwischen Randschichteigenschaften und Kohlenstoff-Tiefenverlauf  

Energy Technology Data Exchange (ETDEWEB)

The influence of a decarburisation process during austenitising of the through-hardenable rolling bearing steel 100Cr6 (SAE 52100) on the rim zone properties of the martensitic through-hardened material was investigated by means of material analysis and diffusion calculations. For this purpose, two specimens were prepared under defined heat treatment conditions, and the near-surface carbon distribution was determined micro-chemically by using secondary ion mass spectrometry (SIMS). In part 1 of the present work, these concentration profiles are compared with the depth variation of the micro-hardness and with the distance curves of the residual stresses and the line broadening ({l_brace}211{r_brace} {alpha}'-Fe diffraction line) both measured by X-ray diffraction (XRD). In addition, microstructure investigations were performed. In part 2, a refined kinetics model of a diffusion-controlled reaction based on the finite element method (FEM) will be applied to the decarburisation ...

2003-08-01

204

Basis for the design of combined fuel cell powerstations; Grundsaetze der Auslegung kombinierter Brennstoffzellen-Kraftwerke  

Energy Technology Data Exchange (ETDEWEB)

A comparative process can be shown for the design of combined fuel cell powerstations. It is worth noting that the output of a combined powerstation working reversibly is independent of the thermodynamic state of the cell, and only depends on the reaction and thermodynamic state of the environment. The potential efficiency of gas-fired combined fuel cell powerstations is estimated at 80%. The fuel cell proves to be an isothermal heat source and not an adiabatic fluegas generator. This applies generally for all combustion power processes. Compared with external reforming, the integration of the reforming in the whole process leads to distinct advantages in efficiency if the possibilities of using the waste heat of intermediate thermal power processes are fully exploited. The plant implementation with an SOFC gas turbine process shows that realisation of a relatively simple plant concept leads to efficiencies distinctly above 70%. The enclosure design is of central improtance for the ...

1995-12-31

205

Aircraft Research Guideline 1999 - 2002: High pressure compressor - preliminary design as a basis for the development of an efficient and environmentally friendly core engine. Final report; Leitlinie Luftfahrtforschung 1999 - 2002: Hochdruckverdichter-Vorauslegung als Grundlagenuntersuchung zur Entwicklung eines Kerntriebwerkes fuer einen effizienten und umweltfreundlichen Antrieb. Schlussbericht  

Energy Technology Data Exchange (ETDEWEB)

This report completes the documentation for the research project 'High Pressure Compressor - Preliminary Design as Basis for the Development of an Efficient and Environmentally Friendly Core Engine' which was funded by the Ministry of Economics of State Brandenburg. The objective of the project is to deliver a preliminary compressor aerodynamic design as well as design studies for an efficient, weight and cost improved compressor. The increase of stage pressure ratio and improved efficiency, whilst stage and blade count is reduced, has been achieved by advanced 3D methods. Compressor stability also at off-design conditions will be retained. The mechanical design focusses on a cost and weight optimised rotor not only for a conventional bladed discs but also for Blish stages. Various options for split casings have been developed and assessed. Alternative vortex reducers based on different design options have been carried out. The results from this project will be ...

2001-08-01

206

A thermographic method as an alternative for gravimetric determination of the particulate diesel emissions; Ein thermographisches Messverfahren als Alternative zur Gravimetrie bei der Ermittlung von Dieselpartikel-Emissionen  

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The basis of assessment for particulate exhaust emissions is the gravimetric analysis of the particle concentration of diluted exhaust gases at temperatures below 52 C. This is very time consuming and takes sufficient sensitivity at low particulate emission rates like downstream of particle filters. For this reason the C/S-method, based on the thermographic analysis of carbon and sulfur, has been developed as an alternative to the gravimetric anallysis. This method yields particle mass as well as the main particle compounds. Comparisons between both methods have been carried out for heavy duty and automobile diesel engines as well as road vehicles and large diesel engines. The tests were conducted with commercial diesel fuel and also with other fuels, such as heavy oils. It could be shown that the C/S-procedure yields the same results as the gravimetric procedure independent of engine, engine mode and kind of fuel. The analysis of all important particulate compounds - elemental carbon ...

1995-09-01

207

A new application of MRT of the lung using ultra-shot turbo spin echo sequences (UTSE); Ein neuer Ansatz in der Magnetresonanztomographie der Lunge mit einer ultrakurzen Turbo-Spin-Echo-Sequenz (UTSE)  

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T{sub 2} weighted ultra-short turbo spin echo sequences were used in five individuals with variations in echo times, delayed triggering and echo intervals. To reduce movement artifacts all examinations were carried out with ECG and respiratory triggering. The sequences giving optimal image quality were then employed in 19 patients having various pulmonary abnormalities. Image resolutions, artifacts, image contrasts and diagnostic value were then judged by two observers and compared with CT. In the first study, a diastole-triggered UTSE sequence with the shortest echo proved optimal (T{sub E}=90 ms, T{sub R}=2-4 s, echo=9 ms, turbo factor=19). In the patient series studied, MRT was inferior to CT with regard to resolution and number of artifacts, but better in respect of contrast and diagnostic value. Using UTSE of the lung, MRT can produce images of good quality. Compared with CT, contrast is better with MRT, offering diagnostic advantages for MRT. (orig./MG) [Deutsch] Zuerst wurde an ...

1996-05-01

208

7. Kassel symposium on energy systems technology: Renewable energy sources and efficient utilization of energy; 7. Kasseler Symposium Energie-Systemtechnik: Erneuerbare Energien und rationelle Energieverwendung  

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This proceedings volume comprises 17 papers on the following subjects: Methane hydrates, compounds of gas and water; Compressed air stroage gas turbine power plants / Scheduled application for load levelling between varying wind power production and power demand; Modern pumped storage power stations in the GW range - the PSW Goldisthal example; Lead batteries - new developments and future applications; Alkaline battery systems for hybrid electric road vehicles; Lighium systems and their applications; Zinc/air cells; Hydrogen storage - metal hydride storage, compressed gas storage, LNG storage; Carbon nanofibres for hydrogen storage; Double-layer condensers - technology, cost, perslpectives; Supercondensers in motor vehicles; Superconducting magnetic energy stores; Flywheel storage - status report; Decentralized energy storage in the European integrated supply grid - the EU project DISPOWER; Intercontinental integration of power supply - perspectives of full-scale power supply on the ...

2002-07-01

209

3D MRI of the colon: methods and first results of 5 patients; 3D-MRT des Kolons: Methodik und erste Ergebnisse  

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Purpose: `Exoscopic` and endoscopic identification of colorectal pathologies via MRI. Methods: 5 patients (36-88 years), two normal and three with different colorectal pathologies (diverticular disease, polyps and carcinoma of the colon), were examined by MRI after colonoscopy. Subsequent to filling of the colon with a gadolinium-water mixture under MRI-monitoring, 3D-data sets of the colon were acquired in prone and supine positions over a 28 sec breathold interval. Subsequently multiplanar T{sub 1}-weighted 2D-sequences were acquired before and following i.v. administration of Gd-DTPA (0.1 mmol/kg BW). All imaging was performed in the coronal orientation. The 3D-data were interactively analysed based on various displays: Maximum intensity projection (MIP), surface shadowed display (SSD), multiplanar reconstruction (MPR), virtual colonoscopy (VC). Results: All of the colorectal pathologies could be interactively diagnosed by MPR. On MIP images some pathologies were missed. VC ...

1997-09-01

210

Web-based training in radiology - student course in the Virtual University of Bavaria; Web-basiertes Training in der Radiologie - Studentenkurs in der Virtuellen Hochschule Bayern (VHB)  

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Purpose: The nint version of the licensing regulation for medical doctors (Approbation Regulation (AR)) sets a benchmark in terms of practical experience, interdigitation of preclinical and clinical studies, interdisciplinary approach, economic efficiency, independence of students, added new teaching and learning modalities, and ongoing evaluation of the progress of the medical students. It is the aim to implement these major points of the AR in a model course for diagnostic radiology and radiation protection within the scope of the Virtual University of Bavaria and test them in practice. Materials and Methods: In cooperation with residents and board certified radiologists, students developed the virtual course 'Web-Based Training (WBT) Radiology' in diagnostic radiology and radiation protection for students in the first clinical semester. A representative target group taken from the student body was asked about the options to get access to the World Wide Web ...

2004-06-01

211

Value of contrast-enhanced MRI of breast after silicone implant; Wertigkeit der Kontrastmittelmagnetresonanztomographie der Mamma bei Wiederaufbau mittels Implantat  

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Early recognition of recurrence and work-up of clinically indeterminate lesions may be impaired after reconstruction with silicone implants due to superimposition of the implant or to scarring. This study was undertaken to evaluate the use of contrast-enhanced MRI in patients with silicone implant after breast cancer. Contrast-enhanded MRI was offered to 169 patients. Comparative two- to three-view mammography was also performed in 169 patients, as well as comparative sonography in 144 patients. Conventional imaging and clinical examination detected only 8/13 recurrences, whereas 12/13 were detected by MRI. One recurrence had been visible as a strongly enhancing 2-mm dot in a previous examination (2 years before), but was not called. It was therefore counted as false negative. In addition, multicentricity was detected by MRI alone in two of three cases. MRI correctly diagnosed scar tissue in all cases with indeterminate findings. However, due to false-positive calls caused by enhancing ...

1997-09-01

212

The development of the high-temperature reactor. In memoriam Prof. Dr. rer.nat. Dr.-Ing. e.h. Rudolf Schulten; Die Entwicklung des Hochtemperaturreaktors. Zum Tode von Prof. Dr. rer.nat. Dr.-Ing. e.h. Rudolf Schulten  

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In the future even more than in the past, nuclear power will be indispensable in the present industrialized countries and in those still under development. The safe, nonpolluting, and economic supply of energy to mankind in the future includes so many different problems that the technology of the high-temperature reactor at its present level of development, and with the possibilities is offers above and beyond those provided by other, established, technologies, does not have to mark the end of some old line of development, but rather should be seen as the starting point of a development offering promise for the future. It is for this very reason that the extensive, valuable knowledge and experience accumulated in the construction, operation, and decommissioning of the AVR and THTR plants, the development of the HTR module and other variants and, last, but not least, the valuable results of projects such as PNP, NFE, and HHT, must be preserved at the research centers and with former ...

1996-08-01

213

Status report about the revision of an IEC standard for personal dose equivalent meters for H{sub p}(10) and H{sub p}(0,07); Statusbericht ueber die Neufassung einer IEC-Norm fuer H{sub p}(10)- und H{sub p}(0,07)-Personendosimeter  

Energy Technology Data Exchange (ETDEWEB)

A working group (SC 45B/WG B8) exists within the international electrochemical commission (IEC) which is working on the combination and revision of the IEC standards 61283, 61323, 61344, 61525 and 61526. All these standards concern direct reading, electronic, personal dose equivalent meters for the quantities H{sub p}(10) and H{sub p}(0,07); they are different with regard to the kind of radiation (photons, and/or beta rays and/or neutrons). The new standard with the number 61526 shall cover the following topics: 1. Combination of all the mentioned standards; 2. Maintenance of the essential requirements of the former standards; 3. Inclusion of the determination of the uncertainty of measurement for the measured dose equivalent value according to the ''Guide to the Expression of Uncertainty in Measurement''; 4. Consideration of all the relevant ISO-standards for reference radiation fields for photon, beta and neutron radiations; 5. Consideration of ...

2001-07-01

214

SPIO-enhanced MR angiography for the detection of venous thrombosis in an animal model; SPIO-unterstuetzte MR-Angiographie zur Detektion venoeser Thromben im Tiermodell  

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Purpose: An animal model is used to investigate whether MR angiography combined with super-paramagnetic particles of iron oxide (SPIO) is suitable for detecting thromboses. Methods: 42 rats in groups of 7 each were examined on days 1, 3, 5, 7, 9 and 11, respectively, after mechanical/chemical thrombus induction in a 1.5 Tesla magnet with a FISP sequence (TR/TE/FA 50 ms/6 ms/40 ). Imaging was performed before and up to 90 minutes after intravenous injection of 30 {mu}mol FE/kg BW of the experimental SPIO (hydrodynamic diameter, 34{+-}17 nm LLS; R1 and R2 relaxivity at 0.47 T, 31 and 57 L/(mmol*s)). MIP reconstructions of MR angiographies were submitted to consensus assessment by two examiners using histology as the gold standard. Results: The image quality of MIP reconstructions was rated as good in 38 of 42 cases. With regard to thrombotic vessel occlusion, MR angiography coincided with histology in 17 of 42 cases and differed in 25, lumen narrowing being overestimated by MRI in 4 ...

1999-03-01

215

Poly-lactic-acid coating of endovascular stents: preliminary results in canine experimental av-fistulae  

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Poly-Lactic-Acid (PLA) was evaluated for coating of vascular endoprotheses in the treatment of experimental arterio-venous-fistulae (AVF). Bilateral carotid-external jugular AVF were created in 5 adult dogs. 7 PLA coated nitinol stents were placed via a transfemoral approach covering 5 AVF. The contralateral AVF remained untreated. Angiography was performed immediately after stent placement, at weeks 1 and 3 and at months 3, 6 and 9. All grafts were removed and underwent histologic examination. In 2 cases the occlusion of the AVF was successful, while misplacement occurred in 3 cases. Occlusion of the parent vessel was disclosed in 3 cases. Histologic examination revealed a mild inflammatory reaction with the presence of macrophages. There was no foreign-body reaction or fragmentation of the arterial vessel wall. PLA, which is a well-known biodegradable material, showed a good mid-term biocompatibility. Elastic mismatch of the non-elastic coating and the self-expandable nitinol stent ...

2001-02-01

216

Operating and commissioning experience with the Dortmund-Derne and Brilon plants; Betriebs- und Inbetriebnahme-Erfahrungen mit den Anlagen Dortmund-Derne und Brilon  

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Initially, the decision of the operator in Dortmund-Derne to select the impact-type separator concept is explained. None of the tenderers for this 52 t/h boiler could supply references for this fluidized bed steam generator concept with staged combustion in a high-expansion fluidized bed. Under the circumstances, the simple configuration of the Steinmueller fluidized bed steam generator, its compact construction, the reduced amount of refractory and the operational behaviour of the boiler resulting therefrom were decisive in the operator`s decision to select this concept. The development schedule shows the individual stages from cold and hot trials in various test rigs and pilot plants to the final design. So far, this fluidized bed steam generator concept has been realized in the plants Derne (52 t/h), commissioned in November 1989, and Brilon (100 t/h), commissioned in November 1990. The discussion on the essential design features points out to the deliberate differences in the two ...

1992-12-31

217

Modernizing steam turbines for nuclear power plants; Modernisierung von Dampfturbinen fuer Kernkraftwerke  

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Economic and safe operation of nuclear power plants requires reliable steam turbines with high efficiencies. The progress in flow mechanics achieved over the past few years has allowed the use of powerful methods of flow calculation in developments of new blading with greatly enhanced efficiencies. Thanks to the latest manufacturing techniques, the newly developed blading systems can be produced at low cost. Next to progress in flow mechanics, also the broadbased use of advanced finite-element calculations resulted in a more thorough grasp of the many problems associated with structural mechanics assessment of steam turbine components. The theoretical methods have been supplemented by comprehensive efforts in fracture mechanics and experimental materials studies, thus helping to create a reliable knowledge base which will help to avoid the dreaded stress corrosion cracking phenomenon, in components of steam turbines. The measures introduced to improve operational reliability already in ...

1996-01-01

218

Modern imaging methods for diagnostic evaluation of tumors of the oropharynx and the oral cavity; Moderne bildgebende Methoden bei der Diagnostik von Tumoren des Oropharynx und der Mundhoehle  

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Differentiating a benign from a malignant lesion by information such as density data, or signal intensities or echo gradients, is not possible with CT, nor MRI, nor ultrasonography. Only some lesions show characteristic signs. Inflammations cannot be difscriminated from malignant tumors. CTs of small tumors in particular are so poor in contrast that it is much more difficult to detect tumors or discriminate them from other lesions, as compared to MR images or ultrasonographs. CT does not detect surface tumors, but is more sensitive than MRI or US in detecting discrete cortical bone lesions. The same applies to small calcified tumors. MRI however is most sensitive in detecting tumor volumes in the yellow marrow, and is the best modality for evaluation of extraossal extension of tumors. CT yields better results than MRI if applied for simultaneous screening of lymph node metastases in the lower neck. MRI frequently is spoilt by movement artefacts. High-resolution, contrast enhanced CT ...

1996-11-01

219

Institute of Toxicology. 1994 annual report on research and development; Institut fuer Toxikologie. Ergebnisbericht ueber Forschung und Entwicklung 1994  

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The R and D activities of the institute focused on two major projects, ``Molecular and cellular environmental toxicology``, and ``Biophysics of multi-cellular systems``. For assessment of health risks emanating from the uptake of heavy metal compounds, work performed under the first mentioned project studies the formation of allergy-inducing metabolic products from membrane lipids, and the effects of related cellular signaling processes. These studies are accompanied by an approach to quantify and classify the toxicity of environmental organometallic compounds. Another major task is research into the pathogenesis of lung disease induced by dusts, gases, and gas-dust mixtures and the liberation of inflammatory agents by immunological cell reactions (alveolar macrophages). Atomic force microscopy is the tool used to visualize the related dynamic changes in bronchial cells. Studies for detection of the localisation and structure of the Fe-Mo co-factor in nitrogenase by means of the method ...

1995-12-31

220

Ganglioneuromas in childhood: MRI and CT characteristics; Ganglioneurome im Kindesalter: CT- und MRT-Charakteristika  

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Purpose: The aim of this study was to demonstrate the typical appearance of ganglioneuromas in computer-assisted tomography (CT), and magnetic resonance imaging (MRI). Material and methods: Retrospective analysis of diagnostic imaging (9 CT, 6 MRI) in 9 children aged 3 to 15 years with the histological diagnosis of ganglioneuroma. Results: The tomographies showed large (max. 13.4 cm in diameter) round or oval tumors with sharp delineation. The sites of the tumors were the retroperitoneum (5), the mediastinum (3), and the adrenal gland (1). Intraspinal tumor involvement occurred in 4 cases. On comparing CT with MRI, MRI was more accurate in defining the intraspinal involvement. The ganglioneuromas were of hypodense appearance in the native CT scan and showed moderate enhancement upon administration of contrast media. In five patients tumor calcifications with a disseminated sprinkled pattern were seen in CT. In MRI T{sub 1}-weighted scans the tumors were homogeneous and hypointense, ...

2000-05-01

221

Forming of Mo and Ti silicides by means of injection molding; Formgebung von Molybdaen- und Titansiliziden ueber das Pulvermetallformspritzen  

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The report describes the processing of TiSi{sub 2}, MoSi{sub 2} and Ti{sub 5}Si{sub 3} by means of metal injection molding (MIM). First, the sintering activities of the three materials were investigated. After this, the viscosities of different mixtures of organic binder and powders of the three materials were determined, and in the final stage, components were produced by injection molding, the binder was removed, and the components were sintered. TiSi{sub 2} in powder form could be sintered to more than 95% of its theoretical density after 4 h at 1386 C. Metallographic analyses proved leaktightness of the component at this density. In the case of Ti{sub 5}Si{sub 3}, it was found that this material requires very long sintering times and high sintering temperatures for sintering to about 94% of its theoretical density. Metallographic analyses showed that only about 90% of the theoretical density was reached. MoSi{sub 2} in powder form could be sintered to only 90% of its theoretical ...

1994-10-01

222

Determination of cartilage thickness in the ankle joint. MRT (1,5 T) comparative anatomical study; Bestimmung der Knorpeldicke am oberen Sprunggelenk. Eine MRT(1,5 T)-anatomische Vergleichsstudie  

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Purpose: The aim of this study was to evaluate the accuracy of MRI in the measurement of cartilage thickness of the ankle joint in comparison to pathologic and histologic specimens. Patients and methods: The ankle joints of four fresh cadaver feet were imaged on a 1.5 T MR-unit in the coronal plane. Standard T{sub 1}-weighted spin echo (SE) and a T{sub 1}-weighted 3D-GE (FLASH-3D) sequence with fat saturation were applied. Following MR imaging, the talus was explanted and cut parallel to the MR images for macroscopic evaluation and histologic specimens were prepared. MRI measurements of the cartilage thickness of the talus were carried out in two ways: Without and with consideration of a transition zone of intermediate signal intensity between hyperintense cartilage and hypointense cortical bone. The data were compared with the anatomic specimens as the gold standard expressing the difference as a percentage value. On histologic specimens thickness of deep calcified cartilage layer was ...

1997-04-01

223

An extended CT scale technique for evaluating periprosthetic bone lesions - an in vitro study; Extended-field CT-Technik zur Evaluation von periprothetischen Knochenlaesionen  

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Purpose: In the present study the reduction of artifacts using an extended CT scale technique was examined in 5 vitallium and 5 titanium-aluminium-vanadium tumor prostheses. Methods: 5 titanium-aluminium-vanadium and 5 vitallium distal femur Mutars {sup trademark} tumor prostheses (Mutars {sup trademark} - Modular Universal Tumor And Revision System) were implanted in 10 human femur specimens. 110 artifical drill hole lesions of 1 mm, 2 mm, 3 mm, 5 mm and 8 mm diameter were placed in the bone around the hexagonal stem of the tumor prosthesis and furthermore in the proximal part of the femur. All specimens were examined using conventional CT and an extended CT scale technique in a slice thickness of 3 mm. Results: In the proximal part of the femur all drill holes could be detected using 3 mm slices, no artefacts were observed. Along the hexagonal stem smooth lines arising from each hexagonal plane could be observed. This made it impossible to detect a 1 mm drill in 1 vitallium and in 1 ...

2001-12-01

224

Role of nuclear medicine and magnetic resonance imaging in cardiac diagnostics; Rolle der nuklearmedizinischen Verfahren und der Magnetresonanztomographie in der kardialen Diagnostik  

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Nuclear medicine and magnetic resonance imaging (MRI) are widely used in cardiac diagnostics. Both techniques have been carefully evaluated and are equivalent for the assessment of regional and global wall motion as well as the evaluation of ejection fraction and cardiac volumes, though MRI is herein currently seen as gold standard. For evaluation of myocardial perfusion, extensive data exist for nuclear imaging, that, next to high diagnostic accuracy for evaluation of coronary artery disease, show incremental prognostic information and allow for independent risk stratification. Because of rapid technical advance, myocardial perfusion imaging has also become feasible with cardiac MRI. Results of recent studies are promising, but the data are few compared to perfusion scintigraphy. For viability assessment in patients with ischemic cardiomyopathy, positron emission tomography (PET) with FDG is currently seen as gold standard. However, single photon emission computed tomography (SPECT) ...

2003-12-01

225

Magnetic resonance imaging. Handbook and atlas; Kernspintomographie. Kompendium und Atlas  

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Magnetic resonance imaging (MRI) as a diagnostic imaging tool relies on the generation of magnetic fields, whereas the computerized tomography (CT) uses X-radiation. The fundamental principle of MRI is the magnetic resonance of paramagnetic atomic nuclei. These nuclei, as e.g. protons (= hydrogen nuclei), are aligned in required orientation by application of a strong magnetic field. Upon simultaneous application of an electromagnetic high-frequency field perpendicular to the axis of the basic magnetic field, and in response to periodical changing of the electromagnetic field at a given frequency, the originally aligned paramagnetic nuclei are forced into a movement similar to that of a ``whipping top``. When the resonance frequency is shut off, the nuclei return to their former, aligned positions, inducing a weak signal in a coil. The series of signals generated by multiple repetition of this process of excitation of nuclei and their return to aligned rest is used as input to a ...

1999-10-01

226

Evaluation of left ventricular volumes in patients with congenital heart disease and abnormal left ventricular geometry. Comparison of MRI and transthoraic 3-dimensional echocardiography; Vergleich der transthorakalen 3D-Echokardiographie mit der MRT zur Bestimmung linksventrikulaerer Volumina bei Patienten mit pathologischer Ventrikelgeometrie aufgrund angeborener Herzfehler  

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Purpose: To assess the new method of 3-dimensional echocardiography in comparison to the 'gold standard' MRI as to its ability to calculate left ventricular volumes in patients with congenital heart disease. Materials and methods: Eighteen patients between the ages of 3.9 to 37.3 years (mean: 12.8{+-}9.7) with a geometrically abnormal left ventricle were examined using a 1.5 T scanner with a fast gradient-echo sequence (TR=14 ms, TE=2.6-2.9 ms, FOV=300-400 mm, flip angle=20 , matrix=128:256, slice thickness=5 mm, retrospective gating) in multislice-multiphase technique. Transthoracic 3D-echocardiography was performed with a 3.5 MHz transducer and a Tomtec {sup trademark} (Munich, Germany) system for 3D reconstruction. Results: Volume calculation was possible in all patients with 3D-echocardiography, but the muscle mass calculation only succeeded in 11 to 18 patients (61%) due to inadequate visualization of the entire myocardium. Comparing MRI and 3D-echocardiography, ...

2003-07-01

227

CT and MRI characteristica of tumours of the temporal bone and the cerebello-pontine angle; CT und MRT tumoroeser Veraenderungen des Schlaefenbeins  

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Tumours lesions of the temporal bone and of the cerebello-pontine angle are rare.This tumours can be separated into benign and malignant lesions. In this paper the CT and MRI characteristica of tumours of the temporal bone and the cerebello-pontane angle will be demonstrated. High resolution CT (HRCT) as usually performed in the axial plane are using a high resolution bone window level setting, coronal planes are the reconstructed from the axial data set or will be obtained directly. With the MRI FLAIR sequence in the axial plane the whole brain will be scanned either to depict or exclude a tumour invasion into the brain. After this,T2-weighted fast spin echo sequences or fatsuppressed inversion recovery sequences in high resolution technique in the axial plane will be obtained from the temporal bone and axial T1-weighted spinecho sequences before and after the intravenous application of contrast material will be obtained of this region. Finally T1-weighted spinecho sequences in high ...

2003-03-01

228

Final Scientific EFNUDAT Workshop  

ScienceCinema

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