Lead tungstate crystals doped with small fractions of praesodynium or molybdenum have been tested in beams of high-energy electrons. The goal of these tests was to study the effects of such dopants on the capability to separate the signal components deriving from the Cherenkov and scintillation light generated by the beam particles. These studies were carried out in view of the possible application of such crystals in dual-readout calorimeters.
Development of the Technology and Control of Electron-Beam Welding Procedure and Production of Full Scale Sector of Endcap CMS Hadron Calorimeter. Preparation for Mass Production.
Effect of Al and AlP particles on the microstructure of near eutectic Mn-Si alloy (Mn-30 wt.%Si) was studied by Electron Probe Micro-analyzer (EPMA) and Differential Scanning Calorimeter (DSC). Crystal lattice correspondence analyses show that both Al and AlP have good lattice matching coherence relationships with MnSi phase, and the addition of Al and AlP particles results in an abnormal eutectic structure, i.e. the eutectic constitution MnSi and Mn{sub 5}Si{sub 3} precipitate separately: MnSi precipitates firstly, and then the Mn{sub 5}Si{sub 3} phase.
The upgraded CDF II detector has collected first data during the initial operation of the Tevatron accelerator in Run II. The simulation of the CDF electromagnetic and hadronic central and upgraded plug (forward) calorimeter is based on the Gflash calorimeter parameterization package used within the GEANT based detector simulation of the Run II CDF detector. We present the results of tuning the central and plug calorimeter response to test beam data.
The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a lead-scintillating fibers sampling calorimeter characterized by high granularity that allows to image the longitudinal and lateral showers development, a key issue to provide high electron/hadron discrimination. The light collection system and the FE electronics are designed to let the calorimeter operate over a wide energy range from few GeV up to 1 TeV. A full-scale prototype of the e.m. calorimeter was tested at CERN in October 2001 using electrons and pions beams with energy ranging from 3 to 100 GeV. Effective sampling thickness, linearity and energy resolution were measured. (8 refs).
This conference report contains the lectures presented at the BMBF status seminar on the cooperative project ``Bodies of landfills``, which took place at Wuppertal on 25th and 26th April 1995. The cooperative project was started in autumn 1993 and studies the long-term behaviour of wastes deposited at landfills in general. Inorganic and municipal wastes are studied separately. (orig./SR) [Deutsch] Der vorliegende Tagungsband enthaelt die Vortraege des BMBF-Statusseminars zum Verbundvorhaben `Deponiekoerper` vom 25. und 26. April 1995 in Wuppertal. Das Verbundvorhaben `Deponiekoerper` wurde im Herbst 1993 begonnen und befasst sich ganz generell mit dem langfristigen Deponieverhalten von Abfaellen. Es ist unterteilt in die Untersuchung von anorganischen Abfaellen und von Siedlungsabfaellen. (orig./SR)
Fundamental investigations into the biosorption of environmentally relevant heavy metals were carried out with different microbial adsorbents, and processes were proposed for industrial effluents. In order to improve the technology of biosorption processes, attempts were made to improve the sorption efficiency of biological sorbents, and investigations were carried out on the immobilisation of biological adsorbents. (orig.) [Deutsch] Es wurden Grundlagenuntersuchungen zur Biosorption von umweltrelevanten Schwermetallen mit verschiedenen mikrobiellen Adsorbentien durchgefuehrt und an technischen Abwaessern Technologievorschlaege erarbeitet. Zur Verbesserung der Technologie von Biosorptionsprozessen wurden Moeglichkeiten der Steigerung der Sorptionsleistung von Biosorbentien erarbeitet und Untersuchungen zur Immobilisierung der biologischen Adsorbentien durchgefuehrt. (orig.)
In this article, the ability of artificial neural networks in prediction of separation in steady two dimensional boundary layer flows is studied. Data for network training is extracted from numerical solution of an ODE obtained from Von Karman integral equation with approximate one parameter Pohlhousen velocity profile. As an appropriate neural network, a two layer radial basis generalized regression artificial neural network is used. The results shows good agreements between the overall behavior of the flow fields predicted by the artificial neural network and the actual flow fields for some cases. The method easily can be extended to unsteady separation and turbulent as well as compressible boundary layer flows. (author)
In this article, the ability of artificial neural networks in prediction of separation in steady two dimensional boundary layer flows is studied. Data for network training is extracted from numerical solution of an ODE obtained from Von Karman integral equation with approximate one parameter Pohlhousen velocity profile. As an appropriate neural network, a two layer radial basis generalized regression artificial neural network is used. The results shows good agreements between the overall behavior of the flow fields predicted by the artificial neural network and the actual flow fields for some cases. The method easily can be extended to unsteady separation and turbulent as well as compressible boundary layer flows. (author)
In the framework of the RIM (Russian Italian mission) program, PAMELA is the experiment devoted to the accurate measurement of the positron and antiproton spectra from the very low energy thresh-old of 100 MeV up to more than 50 GeV, and to hunt antinuclei with sensitivity better than 10{sup -7} in the helium/helium ratio. A permanent magnet equipped by microstrip silicon sensors, measures the particle momentum with MDR=400 GV/c on GF=25 cm{sup 2} sr. An accurate ToF system, a 19 X{sub o} deep imaging calorimeter, an aerogel Cherenkov counter and a TRD detector complement the spectrometer in order an efficient e{sup +-}/p{sup +-} separation and some light isotope identification capability. The PAMELA experiment will be carried out on a 700 km high polar orbit, on board of the Earth-observation meteor-3A satellite, to be launched at the end of 1988.
Quartz fiber calorimetry is a technique the signal generation mechanism of which is based on the Cherenkov effect. In this article we try to give a comprehensive overview of the subject. We start with a general introduction to calorimetry where the basic elements that characterize the development of electromagnetic and hadronic showers are discussed. Then we describe in detail the operation principle and the properties of calorimeters equipped with quartz fibers. The main advantages of this type of calorimeters are the radiation hardness, the fast response and the compact detector dimensions, features that derive from the quartz material and the specific mechanism of operation. A section is devoted to presenting the quartz fiber calorimeters that have been built or planned to in various experiments to operate as centrality detectors, trigger detectors, luminosity monitors or general purpose very forward ...
The following questions, concerning the application of the harmonic oscillator representation (HOR) in the theory of scattering and reactions, are discussed: the formulation of the scattering theory in HOR; exact solutions of the free motion Schroedinger equation in HOR; separable expansion of the short range potentials and the calculation of the phase shifts; `isolated states` as generalization of the Wigner-von Neumann bound states embedded in continuum; a nuclear coupled channel problem in HOR; and the description of true three body scattering in HOR. As an illustration the soft dipole mode in the (11)Li nucleus is considered in a frame of the (9)Li+n+n cluster model taking into account three body continuum effects.
A procedure is described for the isolation and determination of {sup 90}Sr, {sup 226}Ra, {sup 228}Ra and {sup 210}Pb in food. These nuclides are highly radiotoxic, above all for babies and children. Samples are dry ashed, alkali metals are removed as carbonates. Separation from other matrix ions and separation of Ra, Sr and Pb can be achieved with a column of Sr-Spec, an immobilized crown ether. For activity measurements membrane filters with SrSO{sub 4}, Ba(Ra)SO{sub 4} and PbS are prepared. Ra is determined by gamma-spectrometry, {sup 90}Sr and {sup 210}Pb are determined by low-level-betacounting. The determination limits are 10 mBq/kg for {sup 90}Sr and {sup 210}Pb and 50 mBq/kg for {sup 226}Ra and {sup 228}Ra. The procedure is useful for all kinds of foodstuff. (orig.) [Deutsch] Es wird ein Analysengang zur Abtrennung und Bestimmung von {sup 90}Sr, {sup 226}Ra, {sup 228}Ra und {sup 210}Pb in Lebensmitteln beschrieben. ...
The condition for obtaining a calorimetric response linear with energy for hadronic showers and an energy resolution that improves as the incident energy increases is the equalization of the electromagnetic (e) and the hadronic (#pi#) signal responses. This equalization is obtained by exploiting a local hardening effect realized through the insertion of low-Z thin plates between the high-Z absorbers and the active material in a hadronic calorimeter with silicon readout. This effect, which allows the reduction of the calorimeter response to the electromagnetic component of the incoming hadronic showers, has been investigated for different low-Z materials. The relevance of some aspects of this study to the radiation hardness of the calorimeters is also addressed. (orig.).
It is shown that a cosmic gamma-ray telescope made of a multilayer silicon tracker and a imaging CsI calorimeter, is capable of identifying cosmic ray nuclei. The telescope charge resolution is estimated around 4% independently of charge. Simulation methods are used to determine the telescope properties for nuclei detection.
The knowledge shown in this work of the relationships between the oxidation stage of chromium, molybdenum and tungsten and their catalytic activity in some hydrocarbon reactions was achieved by the combination of separate investigations of reduction properties and the catalytic activity of the catalysts concerned. To characterize the electronic state of the reduced surfaces, X-ray photo-electronic spectroscopy was mainly used, supplemented by electron spin resonance. The catalyst activity was measured in conventional apparatus (flow, pulse and gradient-free reactors). (orig.) [Deutsch] Die in dieser Arbeit dargestellten Erkenntnisse ueber die Zusammenhaenge zwischen der Oxidationsstufe von Chrom, Molybdaen und Wolfram und ihrer katalytischen Aktivitaet in einigen Kohlenwasserstoffreaktionen wurden durch die Kombination getrennter Untersuchungen ueber Reduktionseigenschaften und katalytische Aktivitaet der betreffenden Katalysatoren erzielt. ...
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 ...
In this paper it is shown that a measurement of the relative luminosity changes at the LHC may be obtained by analysing the currents drawn from the high voltage power supplies of the electromagnetic section of the forward calorimeter of the ATLAS detector. The method was verified with a reproduction of a small section of the ATLAS forward calorimeter using proton beams of known beam energies and variable intensities at the U-70 accelerator at IHEP in Protvino, Russia. The experimental setup and the data taking during a test beam run in April 2008 are described in detail. A comparison of the measured high voltage currents with reference measurements from beam intensity monitors shows a linear dependence on the beam intensity. The non-linearities are measured to be less than 0.5 % combining statistical and systematic uncertainties.
A data analysis based on an artificial neural network classifier is proposed to identify cosmic ray antiprotons detected with the CAPRICE silicon-tungsten imaging calorimeter against electron background in the energy range 1.2-4.0 GeV. A set of new physical variables, describing the events inside the calorimeter on the base of their different patterns, are introduced in order to discriminate between hadronic and electromagnetic showers. The ability of the artificial neural network classifier to perform a careful multidimensional analysis gives the possibility to identify antiprotons with an electron rejection 408{+-}85 (stat) at 95.0{+-}0.2 (stat)% of signal detection efficiency. The high accuracy achieved by this method improves substantially the efficiency in the evaluation of the cosmic ray antiproton spectrum. (orig.).
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 ...
The current primary standards at NPL for the measurement of absorbed dose to water in high energy photon and electron beams are graphite calorimeters. However, the quantity of interest in radiation dosimetry is absorbed dose to water. Therefore, a new absorbed dose to water standard based on water calorimetry has been developed for use in high energy photon and electron beams. The calorimeter operates at 4 deg C, with temperature control being provided by liquid cooling. The sealed glass inner vessel of the calorimeter was designed to minimise the effect of non-water materials on the measurement of absorbed dose. The temperature sensing thermistor probes were designed and constructed so that glass is the only material in contact with high purity water inside the vessel. Initial measurements of absorbed dose to water made in 6, 10, and 19 MV photons, and 16 MeV electrons agreed, within the measurement uncertainties of ...
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 ...
The multicell proportional chambers at the backing calorimeter of the ZEUS experiment at the storage ring HERA are supplied with a gas mixture of Ar/CO[sub 2] by an open gas system. Flow proportional counters with the build-up [sup 55]Fe sources are used as gas system monitoring detectors. The ZEUS experiment is planned to collect data for about 10 years. Therefore, the lifetime of the Ar/CO[sub 2] mixture should be known. In this paper, the results of laboratory tests and preliminary measurements of the aging effects for monitoring counters are presented. ((orig.))
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 ...
The first volume of the report covers the state of implementation of primary and secondary measures for SO{sub 2}- and NO{sub x} control applied in the most important industrial sectors in Germany. Integrated pollution abatement techniques, called primary measures in this report, such as process integrated measures and low emission processes, have gained increased importance in recent years. The end-of-pipe processes, described here as secondary measures, are generally highly effective. They represent mature technologies, which are capable of achieving significant reductions in SO{sub 2}- and NO{sub x} emissions, and which have been used in particular for retrofitting existing plants. At first, an overview is given regarding the development of SO{sub 2}- and NO{sub x} emissions in selected European countries during the last 20 years and in Europe. Current national and European emission limits and emission guidelines on SO{sub 2}- and NO{sub x} emissions from stationary sources are ...
To study the biogeochemical behaviour, mobility and transport of trace metals in seawater (Se, Mo, Cd, Pb, Hg, Cu, Co, Fe, Ni, Zn), in suspended particulate matter (Mo, Cd, Pb, Cu, Co, Fe, Ni, Zn, Al, Mn) and in sediments of the inner and outer coastal regions, samples were collected on 3 separate cruises during a one year period (Mai 1993 - April 1994) at 20 stations in the coastal area of Mecklenburg-Vorpommern. Standard hydrographic parameters, nutrients and dissolved oxygen were also measured. Priority was taken to establish the methods for the determination of molybdenum and selenium. To study the behaviour of these two elements in detail, longterm measurements were carried out weekly between January 1993 and June 1994 at the `Messsteg/Warnemuende`. Because of parallel measurements correlations to biological, chemical and hydrographic parameters have been tested. The total database is summarized in the Appendix. The results are presented in 30 figures and 13 ...
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 ...
The Neutral Beam Test Facility (NBTF) to be realized in Padoa will test the Neutral Beam Injection (NBI), one of the Heating and Current Drive Systems foreseen for ITER. The NBI is based on the acceleration of hydrogen or deuterium negative ions up to 1 MeV. This work has been aimed at assessing the tritium release from the NBTF in order to provide data for the safety analysis. In particular, the diffusion of the tritium through the neutral beam target material (the CuCrZr alloy calorimeter panels) has been assessed by using literature data of the diffusion coefficient. The tritium generated inside the calorimeter panels moves into both the vacuum and water side: the tritium diffusion flux has been evaluated during the beam-on (200 deg. C) and the beam-off (20 deg. C) phases of the NBTF experiments consisting of an interim campaign and a final test. The penetration depth of the tritium through the 2 mm thick CuCrZr alloy material has been also ...
The Neutral Beam Test Facility (NBTF) to be realized in Padoa will test the Neutral Beam Injection (NBI), one of the Heating and Current Drive Systems foreseen for ITER. The NBI is based on the acceleration of hydrogen or deuterium negative ions up to 1 MeV. This work has been aimed at assessing the tritium release from the NBTF in order to provide data for the safety analysis. In particular, the diffusion of the tritium through the neutral beam target material (the CuCrZr alloy calorimeter panels) has been assessed by using literature data of the diffusion coefficient. The tritium generated inside the calorimeter panels moves into both the vacuum and water side: the tritium diffusion flux has been evaluated during the beam-on (200 deg. C) and the beam-off (20 deg. C) phases of the NBTF experiments consisting of an interim campaign and a final test. The penetration depth of the tritium through the 2 mm thick CuCrZr alloy material has been also ...
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 ...
This report describes the sampling and chemical analyses of smoke gas components for combustion performed in the SP Industry Calorimeter, where continuous measurements of oxygen, carbon dioxide and carbon monoxide are an integrated part of the Calorimeter system. On-line measurements of nitrogen oxides and total amounts of unburnt hydrocarbons were performed. Hydrogen cyanide, hydrogen chloride and ammonia in the smoke were sampled and absorbed in impinger bottles and subsequently analyzed using wet chemical techniques. An adsorbent sampling system was designed to allow the identification and quantitative analysis of individual organic compounds in the smoke. Gas chromatography was utilized with a mass spectrometric detector for the identification and a FID for quantification of the total amounts as well as individual components. A procedure for cleaning the smoke gas duct in between the combustion experiments was designed and found to be ...
Yet designed to measure charged component of the cosmic rays, the foreseen Alpha Magnetic Spectrometer (AMS-02) could also release {gamma}-ray studies, in the energy range from GeV to TeV, using the tracker system, for {gamma}-rays converted in e{sup +}e{sup -} pair, and the electromagnetic calorimeter. In the first part of the thesis are described the calibrations and the performances of the engineering model of the calorimeter, obtained from the analysis of data taken during a test-beam performed at CERN in July 2002. In the second part of the thesis, the AMS-02 discovery potential for {gamma}-astrophysics is presented. While exposure maps of the {gamma}--sky are computed for one year of data taking with the {gamma}--detectors, the acceptance of the calorimeter is obtained from Monte-Carlo simulations. The AMS-02 potential is then estimated for signals from the Vela pulsar and for some supersymmetric signals from the ...
ATLAS is one of the four experiments which will take place at the LHC, the CERN future protons collider. This accelerator, which should start in 2007, will allow to continue the studies carried out by its predecessors, as the standard model Higgs boson and new physics searches. The very high luminosity -10 fb{sup -1} during the first three functioning years, then 100 fb{sup -1}- and the 14 TeV in the frame center will ease these studies. The Centre de Physique des Particules de Marseille took part in the ATLAS collaboration, taking in charge half of the End-cap electromagnetic calorimeter modules construction. The description of this sub-detector and the construction steps, in particular the electrical tests which allow the stacking validation, are presented in this document. These tests results, obtained for the live first production modules, are analysed. The pre-series module (module 0) performances, obtained with beam tests performed at CERN in 1999, are also ...
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. ...
We report on the activities of the High Energy Physics Group at the University of Texas at Arlington for the period 1994-95. We propose the continuation of the research program for 1996-98 with strong participation in the detector upgrade and physics analysis work for the D0 Experiment at Fermilab, prototyping and pre-production studies for the muon and calorimeter systems for the ATLAS Experiment at CERN, and detector development and simulation studies for the PP2PP Experiment at Brookhaven.
The cosmic antiparticle ring imaging Cherenkov experiment (CAPRICE) flew on a stratospheric balloon 8-9 August 1994 over northern Canada and collected data for more than 21 hours with less than 5 g/cm{sup 2} of residual atmosphere. The instrument includes a solid radiator RICH detector and an electromagnetic calorimeter for particle identification in the magnetic spectrometer. Preliminary antiproton and positron identification capabilities are presented.
Experimental results of ageing effects in proportional counters are presented. The measurements were carried out for 158 ZEUS-BAC gas system monitoring counters. Deterioration of the pulse height distribution in azimuth and along the anode wire are presented. The influence of water admixture on counting gas is also described. (orig.).
This presentation summarizes the present upgrade R&D projects in the TileCal collaboration. One project studies the possibility to divide the drawers into smaller minidrawers to simplify maintenance. There are three different front-end projects. There are also projects dealing with high voltage and low voltage distribution, projects for developing PMT dividers, low voltage electronics, data transmission and off-detector electronics.
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 ...
The agglutination of human platelets by ristocetin and von Willebrand factor was inhibited by aggregated immunoglobulin (Ig)G and by Fc fragments of IgG, but not by Fab, F(ab′)2 or...Full Text Available
Human Factor VIII/von Willebrand factor, purified by calcium citrate-cellulose chromatography and 4% agarose gel filtration was subjected to sodium dodecyl sulfate gel electrophoresis on gels containing...Full Text Available
In this article we obtain an alternative formulation of the von Mises type conditions for p-max stable laws in terms of generalized log Pareto distributions (glogPds). Relationship between the rate of convergence of extremes and the remainder terms in the von Mises type conditions is investigated. It is shown that the rate of convergence in the von Mises type conditions for p-max stable laws determines the distance of the underlying distribution function from a glogPd.
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 ...
... Separation," AGARD,Rept 272, April 1960, ... Leading Edge Effect on Supersonic Boundary Layer Flow." ... of Gas Injection in Separated Flows." TCEA, ...
The effect of partial and total replacement of tungsten by molybdenum on the mechanical technical properties were investigated with the cold work steel 60 WCrV 7 (DIN 1.2550). While maintaining the total quantity of tungsten atoms and/or molybdenum atoms in the steel, no differences occur in the type of the separated carbides. After annealing in the range of the pearlite stage with annealing times of up to 150 h, the carbide phases M/sub 23/C/sub 6/ and MC are, besides alpha iron, also present. In short-time annealed states also M/sub 6/C carbides occur. These are formed during austeniting and remain in the steel as residual carbides in austeniting treatment carried out under normal conditions. Compared with tungsten alloyed steel, there is an increased formation of M/sub 6/C carbides in molybdenum alloyed steels during austeniting. By a long-time annealing treatment in the range of the pearlite stage, the M/sub 6/C carbides are dissolved in favour of the M/sub ...
PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range (protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of $10^{-8}$). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15 2006 in a $350\\times 600 km$ orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the satellite. In self-trigger ...
A prototype trumpet type nonimaging secondary concentrator was designed and fabricated for use with the Cummins Power Generation (CPG) 7.5 kW{sub e} dish-Stirling system. A set of operational tests was carried out with a high temperature heat pipe receiver and gas-gap calorimeter. These tests have successfully alleviated any operational concerns about the effectiveness of active water cooling for such devices. The authors obtained over two full days of testing with the cavity receiver operating at its design temperature of 660 C while the trumpet throat temperature remained {approx_equal} or less than 100 C. In addition, these tests have shown that the thermal isolation of the trumpet from the hot receiver is very effective. Highly variable insolation, instabilities in the temperature controller on the calorimeter, and a poor match between the optical quality of the primary and the design of the trumpet have made detailed quantitative results ...
PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of 10^-8). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15, 2006 in a 350*600 km orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the satellite. In self-trigger mode the ...
The thermodynamic properties of aqueous solutions containing ammonia and sour gases such as carbon dioxide, sulfur dioxide, or hydrogen sulfide must be known in many applications. A typical example is the cleaning of raw gases in power stations. The enthalpy changes upon partial evaporation of aqueous solutions containing ammonia and of aqueous solutions containing ammonia and carbon dioxide were measured at temperatures from 313 to 393 K with a thin film evaporator flow calorimeter. The molalities of ammonia and carbon dioxide entering the calorimeter ranged up to 12 and 6 mol/kg, respectively. The physicochemical model originally developed by Edwards et al. (1978) and further modified and extended by Kurz et al. (1995) to describe phase equilibria in aqueous systems containing ammonia and carbon dioxide is used to derive a predictive enthalpy model for this complex, chemical reactive system. Comparisons between the new experimental results ...
Energy expenditure (EE) of four adult men on a weight-maintenance diet was estimated by use of doubly labeled water, intake balance, and direct and indirect calorimetry. The doubly labeled water (2H218O) method was used to estimate free-living EE for 13 d. Metabolizable energy (ME) intake was used to estimate free-living EE for 1 wk. The subjects' 24-h EE was measured in a dual direct-indirect room calorimeter on 3 alternate days. Estimates of free-living EE as measured by ME intake and doubly labeled water indicate agreement between the two methods (mean difference +/- SEM, -1.04 +/- 0.63%). Measurements of EE with indirect and direct calorimetry are equivalent (mean difference 0.63 +/- 0.44%). The daily EE measured by doubly labeled water in these free-living adults over a 13-d period was 15.01% greater than the 24-h EE measured within the calorimeter.
Solution and dilution enthalpies of aqueous solutions of potassium diclofenac salt (K_DC) were measured by an isoperibolic calorimeter at 298.15 and 318.5?K. Heat capacities of the solutions with concentrations 0.002?0.09?mol?kg?1 were obtained at the temperature interval of 288.15?318.15?K using a scanning adiabatic microcalorimeter. The virial coefficients were derived from Pitzer?s model, and the excess thermodynamic functions of both the solvent and the solute of the solution were calculated. The concentration and temperature dependencies of thermodynamic characteristics of the solution were analyzed and discussed.
Thermodynamic states encountered during combustion of Aluminum powder in Shock-Dispersed-Fuel (SDF) explosions were analyzed with the Cheetah code. Results are displayed in the Le Chatelier diagram: the locus of states of specific internal energy versus temperature. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f(T) suitable for specifying the thermodynamic properties required for gas-dynamic models of combustion in explosions.
We have measured the neutron capture and fission cross section of "2"3"3U at the neutron time-of-flight facility n-TOF at CERN in the energy range from 1 eV to 1 MeV with high accuracy by using a high performance 4#pi# BaF_2 Total Absorption Calorimeter (TAC) as a detection device. The method, based on the shape analysis of the TAC energy response, allowing to disentangle between #gamma#'s originating from fission and capture will be presented as well as the first very preliminary results. (authors)
This document presents the current status of SiD's effort to develop an optimized design for an experiment at the International Linear Collider. It presents detailed discussions of each of SiD's various subsystems, an overview of the full GEANT4 description of SiD, the status of newly developed tracking and calorimeter reconstruction algorithms, studies of subsystem performance based on these tools, results of physics benchmarking analyses, an estimate of the cost of the detector, and an assessment of the detector R&D needed to provide the technical basis for an optimised SiD.
A search for monopoles and tachyons at ground level was carried out using an arrangement consisting of an ionization calorimeter and two hodoscope detectors. No clear evidence for these particles was obtained. The flux of monopoles with velocities beta approximately 0.01 is found to be less than 5.1 x 10 to the minus 13th power square centimeters s(-1) sr(-1) (95% cl.). The upper limit on the tachyon flux density is set as a 6 x 10 the minus 9th power particle/square centimeter event.
The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q{sup 2}=1.0-4.8 GeV{sup 2} with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.
The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q2=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.
It is built and tested a transition radiation detector (TRD) to discriminate positrons from protons in the balloon flight TS 93 experiment. It is presented the TRD performance using flight data obtaining a proton-positron rejection factor of the order of 10{sup -3}. During the 24 hour flight, the data in the momentum range 4-50 GeV/c are collected. Using the TRD together with the Silicon calorimeter, it is achieved an overall rejection factor of about 10{sup -5} of positron against the proton background over the entire momentum range.
Isobaric molar heat capacities of powder and microsphere form of Li2TiO3 (s) and powder form of LiAlO2 (s) and Li2ZrO3 (s) were measured using a heat flux type differential scanning calorimeter in the temperature range 320 - 870 K. Specific heat capacities of LiAlO2 (s) was found to be much larger compared to those of Li2TiO3 (s) and Li2ZrO3 (s). (author)
... Agard Report 272,1960 ... and reattached subsonic turbulent flows obtained downstream ... of flow separations due to deflected control surfaces. ...
Under the repository storage conditions of Eram and Konrad, waste packages designed for permanent storage must not contain or release freely mobile liquids, except for the minimum residues attainable by reasonable efforts or unavoidable. In accordance with a directive issued by the German Federal Ministry for the Environment (BMU), waste conditioning must be carried out so as to minimize waste volumes and, if possible, on the site where the waste arises. Liquid waste is conditioned most effectively by drying. At the present time, various different processes for drying liquid waste are employed as reflected by the state of the art: The Robe process; roller drying; the RDA process; Favorit; in-drum drying; and HPA liquid waste drying with make-up feed. The HPA process offers these advantages: Drying under atmospheric conditions, which means high level of dryness (freely mobile and releasable water is removed); the residual water content is 10%; isothermal drying by hot air, which ...
PurposeAlthough the safety and feasibility of partial adrenalectomy in patients with von Hippel-Lindau syndrome have been established, long-term outcomes have not been examined. In this study we evaluate the recurrence and functional outcomes in a von Hippel-Lindau syndrome cohort treated for pheochromocytoma with partial adrenalectomy with a followup of at least 5 years. Materials and MethodsWe reviewed the records of patients with von Hippel-Lindau syndrome treated with partial adrenalectomy for pheochromocytoma at the National Cancer Institute. Demographic, germline mutation status, surgical indication, oncologic and functional outcome data were collected. Local recurrence was defined as radiographic evidence of recurrent tumor on the ipsilateral side of partial adrenalectomy. Patients ...
The regulation of blood vessel formation is of fundamental importance to many physiological processes, and angiogenesis is a major area for novel therapeutic approaches to diseases from ischemia to...Full Text Available
Turbine sets are inspected at their overhaul intervals throughout their operating lives. Using three examples, the present article describes the procedure in the inspection and assessment of steam turbines during overhauls and also deals with rehabilitation measures. In addition to the usual non-destructive tests and the recording of findings, computational life assessments are also considered. (orig.) [Deutsch] Turbosaetze werden waehrend ihrer Betriebszeit anlaesslich von Revisionen ueberprueft. Anhand von drei Beispielen wird in diesem Beitrag die Vorgehensweise bei der Pruefung und Bewertung von Dampfturbinen bei Revisionen und fuer Rehabilitationsmassnahmen dargestellt. Neben ueblichen zerstoerungsfreien Pruefungen und Befundaufnahmen erfolgten in Verbindung damit auch rechnerische Lebensdauerbewertungen. (orig.)
... XVIII, n. 1, p. 50-67. [2] G. Becker: Zeitskalenprobleme: jahreszeitliche Gangschwankungen von Atomuhren, PTB Mitteilungen 92 2/82, p. 105-113. ...
A process is described for removing carbon dioxide from a feed stream of natural gas, having at least methane, ethane and heavier hydrocarbon, comprising: separating the feed stream in a first separator to form a first stream, having substantially all of the propane and heavier hydrocarbons and carbon dioxide and ethane, and a second stream, having methane, carbon dioxide and ethane; mixing the second stream with a polar compound to form a third stream; separating the vapor and liquid of the third stream in the bottom portion of an absorber; absorbing carbon dioxide and ethane from the separated vapor of Step C in a lean portion of the polar compound in the absorber, the absorber carbon dioxide and ethane forming a fourth stream; separating the ethane from the polar compound and carbon dioxide in a separator; separating the first stream in a ...
A separation phenomenon occurring during the Charpy impact test of API X80 pipeline steels was investigated in the present study. A detailed microstructural analysis of fractured impact specimens showed that the band structure of bainite elongated along the rolling direction worked as prior initiation sites for separations, and that the number and length of the separations increased with the increasing volume fraction of bainite. In the steels having high work hardenability, tearing-shaped separations were found because the hammer-impacted region was seriously hardened during the impact test, which led to the reduction in the impact toughness. As the test temperature decreased, the tendency toward separations increased, but separations were not found when the cleavage fracture prevailed at very low temperatures. These findings suggested that the formation of ...
Q/sub ..beta..-values are determined for 18 nuclei (Zr-, Nb-, Mo-, Tc-, Ru- and Rh-nuclides) with mass numbers 101 less than or equal toA less than or equal to106 and A=109 from measurements of beta decay energies which were carried out at the LOHENGRIN mass separator at the Institut Laue-Langevin in Grenoble (France). The given Q/sub ..beta..-values between 2 and 8 MeV show errors of about 1.5% (with the exception of /sup 103/Zr and /sup 105/Nb resp. and /sup 103/Tc for which larger errors result due to statistical resp. systematic reasons): /sup 101/Zr 5500+-70, /sup 101/Nb 4580+-45, /sup 102/Zr 4670+-40, /sup 102/Nb 7230+-70, /sup 103/Zr 6790+-240, /sup 103/ 5740+-70, /sup 103/Mo 3575+-80, /sup 103/Tc 2585+-70, /sup 104/Nb 8250+-130, /sup 104/Mo 2180+-40, /sup 104/Tc 5520+-100, /sup 105/Nb 6570+-150, /sup 105/Mo 4885+-80, /sup 105/Tc 3750+-60, /sup 106/Mo 3515+-45, /sup 106/Tc 6540+-70, /sup 109/Ru 4150+-80, /sup 109/Rh 2550+-50 (all values in keV). For the ...
In technical combustors, flow and combustion processes inside the combustion chamber determine the design and also the safety of the plant. A modelling technique was developed at TU Dresden which comprises both numerical simulations and experimental data and thus achieves a high degree of transparency in its visualisation of the processes inside the combustion chambers under investigation. With the experience gained, numerical models of commercial simulation software (FLUENT, CFX) can be validated by measured values, and potential applications of the programs can be investigated. The first stage of experimental modelling consisted in isothermal (cold) modelling in consideration of flow-relevant similarity characteristics. In the reactive, non-isothermal models, the fuel/air ratio and temperature conditions inside the original combustion chamber were modelled as well. In order to obtain detailed data on the combustion conditions at the burner, measurements were made on a ...
The brochure reports on the construction and method of operation of heat pumps: - Efficiency and temperature difference - output figure - circuit processes - saving of primary energy - monovalent and bivalent plants - absorber, earth collectors - heat recovery. (HW) [Deutsch] Die Broschuere berichtet ueber den Aufbau und die Wirkungsweise von Waermepumpen: - Wirkungsgrad und Temperaturdifferenz - Leistungszahl - Kreisprozesse - Einsparung von Primaerenergie - monovalente und bivalente Anlagen - Absorber, Erdkollektoren - Waermerueckgewinnung. (HW)
Zusammenfassung Der vom Bundesamt f?r Sicherheit in der Informationstechnik (BSI) entwickelte Ansatz des IT-Grundschutzes war bereits Gegenstand von Beitr?gen in der DuD. Inzwischen hat das ?Grundschutzhandbuch? Eingang in die internationale Standard-Familie ISO 2700x gefunden. Der Autor berichtet ?ber die Erfahrungen mit den ersten durchgef?hrten Zertifizierungen nach dem neuen ISO-Standard auf der Basis von IT-Grundschutz.
The ash of biomass fuels was analysed in order to identify its inorganic chemical characteristics. The experiments were carried out using different methods of extraction. The accuracy of the measurements was verified by comparative analyses using certified samples. The composition was shown to vary with the fuel type and ash fraction. In the case of arsenic and the toxic heavy metals cadmium, mercury and lead, accumulation factors of 1.4 to 43 were measured in the tissue filter ash. [German] Fuer die Bestimmung der stofflichen Eigenschaften von Biobrennstoffaschen werden neben der fuer die Ermittlung von Stoffbilanzen notwendigen Analyse der Gesamtgehalte, in Abhaengigkeit von der Zielsetzung und den gesetzlichen Vorgaben, unterschiedliche Extraktionsverfahren eingesetzt. Fuer die Gesamtgehaltsbestimmung wurden aus laborinternen Wiederholungsuntersuchungen sowie einem laborexternen Analysenvergleich Kenngroessen fuer die ...
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 ...
The examples quoted show that damage is mostly due to faults of design and construction or faulty operation. The ever shorter development cycles, the further development of existing constructions and cost pressure owing to price slumps are very important in this context. Careful endoscopic inspections and monitoring and early identification of beginning damage helps to prevent major damage and follow-up damage. The causes of changing operational performance must be established as early as possible to prevent larger damages from being caused by continued operations.(orig.) [German] Die vorgestellten Schadenbeispiele zeigen, dass die Schaeden vorwiegend durch Auslegungsfehler und Konstruktionsfehler aber auch durch Bedienungsfehler verursacht wurden. Die immer kuerzeren Entwicklungszeiten fuer Neukonstruktionen und die Weiterentwicklung vorhandener Konstruktionen sowie der Kostendruck infolge des Preisverfalles sind hierbei von grosser Bedeutung. Weitherhin ist die ...
In this paper, necessary and sufficient conditions for successful detection of errors in a binary adder by any separate code are developed. The author demonstrates the existence of separate checking codes for addition modulo (2 sup n) ( n > or = 4) and mo...
Convolutive mixtures of signals, which are common in acoustic environments, can be difficult to separate into their component sources. Here we present a uniform probabilistic framework to separate...Full Text Available
Children Who Won't Go To School (Separation Anxiety) No. 7; Updated March 2011 Click here to ... and behaviors are common among children with separation anxiety disorder. The potential long-term effects (anxiety and ...
shown of inviscid shocked flow with and without separation and shock-free flow with separation. An Euler solu- tion with ... THE existence of flow separation and recirculation is ..... Solutions for AGARD Test Cases," NASA TM, to be published. ...
Pyrolysis and combustion of CH are investigated. In order to reduce the work required for the present combination of parameters, the following substances were selected: Hexachloroethane, hexachlorocyclohexane, hexachlorobenzene and hexachlorophene. The model substances were pyrolyzed or combusted in varying conditions, and the combustion or pyrolysis products were analyzed. Only the main products were of interest; trace components are important only as far as they may throw light on the reaction mechanisms. The furnace design resulted in incomplete combustion and pyrolysis reactions, so that products of all stages of combusition or pyrolysis were available for analysis. Reaction processes can be derived from the products. As an alternative to thermal treatment of refuse, biological degradation of chlorinated hydrocarbons was gone into. The efficiency of decomposition by microorganisms was to be compared with the efficiency of thermal destruction of chlorohydrocarbons. The ...
The neutron capture cross-section of {sup 234}U has been measured for energies from thermal up to the keV region in the neutron time-of-flight facility n-TOF, based on a spallation source located at CERN. A 4{pi} BaF{sub 2} array composed of 40 crystals, placed at a distance of 184.9 m from the neutron source, was employed as a total absorption calorimeter (TAC) for detection of the prompt {gamma}-ray cascade from capture events in the sample. This text describes the experimental setup, all necessary steps followed during the data analysis procedure. Results are presented in the form of R-matrix resonance parameters from fits with the SAMMY code and compared to the evaluated data of Endf in the relevant energy region, indicating the good performance of the n-TOF facility and the TAC. (authors)
On the 15th of June 2006 the PAMELA experiment, mounted on the Resurs DK1 satellite, was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. PAMELA is a satellite-borne apparatus designed to study charged particles in the cosmic radiation, to investigate the nature of dark matter, measuring the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved, and to search for antinuclei with unprecedented sensitivity. The apparatus comprises a time-of-flight system, a silicon-microstrip magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail catcher scintillator and a neutron detector. The combination of these devices allows charged particle identification over a wide energy range.
The CDF II eXtremely Fast Tracker (XFT) is the trigger processor which reconstructs charged particle tracks in the CDF II central outer tracking chamber. The XFT tracks are also extrapolated to the electromagnetic calorimeter and muon chambers and are associated to electromagnetic clusters and muon stubs to generate trigger electron and muon candidates. The steady increase of the Tevatron instantaneous luminosity and the resulting higher occupancy of the chamber demanded an upgrade of the original system, which performed tracking only in the transverse plane of the chamber and was consequently affected by a significant level of fake tracks. In the upgraded XFT, tracking is reinforced by using additional data from the stereo layers of the chamber to reduce the level of fake tracks and to perform three-dimensional track reconstruction. A review of this upgrade is presented.
We have searched for neutron-antineutron oscillations using the 5.56 fiducial kiloton-year exposure of the Soudan 2 iron tracking calorimeter. We require candidate n-nbar occurrences to have .GE. 4 prongs (tracks and showers) and to have kinematics compatible with nbar-N annihilation within a nucleus. We observe five candidate events, with an estimated background from atmospheric neutrino and cosmic ray induced events of 4.5 \\pm 1.2 events. Previous experiments with smaller exposures observed no candidates, with estimated background rates similar to this experiment. We set a lifetime lower limit for oscillation time in iron: T_A(Fe) > 7.2x10^{31} years. The corresponding lower limit for oscillation of free neutrons is \\tau_{n-nbar} > 1.3x10^8 seconds.
This thesis describes hadron reconstruction at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. The focus is on the particle flow reconstruction of these objects. This thesis revisits the subject of the CMS calorimeters' non-linear response to hadrons. Data from testbeam experiments conducted in 2006 & 2007 is compared with simulations and substantial differences are found. A particle flow calibration to correct the energy response of the testbeam data is evaluated. The reconstructed jet response is found to change by ~ 5% when a data-driven calibration is used in place of the calibration derived from simulation. Collision data taken at the early stage of CMS' commissioning is also presented. The hadron response in data is determined to be compatible with testbeam results presented in this thesis. This thesis also details the use of neural networks to improve the energy measurement of hadrons at CMS. The networks ...
Propanolol is a betablocker drug used in the treatment of arterial hypertension related diseases. In order to achieve an optimal performance of this drug it is important to consider the possible interactions of propanolol with plasma proteins. In this work, we have used several experimental techniques to characterise the effect of addition of the betablocker propanolol on the properties of bovine plasma fibrinogen (FB). Differential scanning calorimeter (DSC), circular dichroism (CD), dynamic light scattering (DLS), surface tension techniques and atomic force microscopy (AFM) measurements have been combined to carry out a detailed physicochemical and surface characterization of the mixed system. As a result, DSC measurements show that propranolol can play two opposite roles, either acting ...
Using EAS data from the EAS-EXC group (EAS plus hadronic calorimeter and nuclear emulsion-X chamber hybrid experiment) on Mount Chacaltaya during the 1990's the fractal properties of the energetic cosmic ray fluxes was investigated. A discrimination in the hadron content of the energetic primaries furnishes two different data samples, the total EAS fluxes and the hadron-less fluxes. The sidereal diurnal variation of the hadron-less EAS time variation shows values of 0.5% with a phase at about 2.29 hr sidereal time. With the help of the Crassberger Procaccia algorithm the fractal dimensions have been investigated of, on the one hand, the differences in arrival times of the hadron-less showers and on the other hand the EAS fluxes time series with an integration time of five min. The obtained fractal dimensions show inconclusive evidence of continuous chaotic component in the data samples investigated.
As a new high-voltage cathode candidate for post 4V cathodes, ordered-olivine LiCoPO{sub 4} and fluoride phosphate, Li{sub 2}CoPO{sub 4}F were synthesized by solid-state reaction. Their structures were identified by neutron diffraction. The 5V discharge profiles were demonstrated using coin-type cells. Two important issues for commercial use, metal dissolution and oxygen release at elevated temperatures, were also tested with an atomic absorption spectrophotometer and differential scanning calorimeter, respectively. (author)
The flame retardancy of polybutylene terephthalate (PBT) was studied focusing on the effect of various oxides. Thermo-gravimetric analysis, pyrolysis/gas chromatography/mass spectrometry, and elemental analysis (EA) were used to analyze the flame retardancy, which were observed through the UL-test and a cone calorimeter. Many oxides influenced the flame retardancy and some of them could suppress the flammability of PBT. In particular, the blended-PBTs with ZnO and V2O5 accelerated the degradation and the edges of oxygen consumption were shorter than neat-PBT although the flammability became poorer. The quantitative analysis of the scission products and the results of EA showed that hydrolysis, successive dehydration, and other various reactions changed the scission route to generate less f...
As a method to make use of a high latent heat of a liquid-solid phase change material in a confined convective heat transfer, a phase change material, lauric acid, was encapsulated in a tiny hollow sphere, and mixed with water, forming a slurry of microencapsulated phase-change material (MCPCM slurry). Four different sizes (200, 100, 50, and 25 {mu}m ID) of MCPCMs were tested in this study. Thermal characteristics of the pure lauric acid and lauric acid MCPCMs were tested by a differential scanning calorimeter. Viscosity of the slurries of water and the capsules was measured by a rotating viscometer. The slurries were also tested in a convective-heat-transfer-test apparatus. (author). 11 refs., 5 figs., 1 tab.
The total hemispherical emittance of an oxide film that formed on 6061-T6 aluminium alloy parts in the Tower Shielding Reactor-II at Oak Ridge National Laboratory was measured from 295 to 773 K using an emissometer and/or a calorimeter. The emittance of this film was critically needed for heat transfer calculations in a simulated loss-of-coolant accident of the reactor. X-ray diffraction analysis identified the film as boehmite (Al_2O_3 x H_2O), which dehydrated to alumina (Al_2O_3) upon heating above 473 K. The measured emittances for the alumina film are in excellent agreement with published values for anodized aluminum films and for bulk alumina. Published values of the emittance of boehmite could not be found for comparison, but evidence is presented that some anodization processes for aluminum yield boehmite and not alumina films.
We investigated the magnet field dependence of the X-ray pulse height and the critical current of a Ti/Au bilayer TES micro-calorimeter. The pulse height was strongly affected by the magnetic field intensity applied perpendicularly to the TES surface. We found that the critical current at zero temperature, I c0, decreased by a factor of two by applying a magnet field of ?10??T. Our data are consistent with a TES sensitivity proportional to (I/I c0)?2/3, as predicted by the Ginzburg-Landau theory. This fact implies that the shape of the R?T curve of the TES is partly determined by the critical current of the superconductor. In order to make our TES microcalorimeters less sensitive to the external magnetic field, we fabricated devices equipped with on-chip magnetic shielding. One device has ...
impflrtant to the understanding of complex vortical flows. ... tions like the slender wing, flow separations are controlled in the s,. ...... 10, AGARD LS-121, Dec. ...
... In: Separated Flows, AGARD CP No. ... on thin wings in two-dimensional incompressible flow. ... fields in the region of separating and reattaching flows. ...
flow over the suction surface of a modern low- ..... the flow because of its proximity to the separation point ..... Pressure Turbines, AGARD Lecture Series 167, ...
Methods were developed for the separation of radioactively labeled carbohydrate components of proteoglycans by isocratic ion-moderated partition HPLC. Neutral sugars were separated after hydrolysis in trifluoroacetic acid with baseline separation between glucose, xylose, galactose, fucose, and mannose. N-Acetylneuraminic acid, N-acetylated hexosamines, glucose, galactose, and xylitol were likewise well separated from each other under isocratic elution conditions. Glucuronic acid, iduronic acid, and their lactones were separated after hydrolysis in formic acid and sulfuric acid. Glucosamine, galactosamine, galactosaminitol, and glucosaminitol were separated by HPLC on a cation exchanger with neutral buffer after hydrolysis in hydrochloric acid. THe separation techniques also proved useful in fractionation of exoglycosidase digests of O- and ...
This patent describes a process for removing carbon dioxide from a feed stream of natural gas having at least methane, ethane and heavier. It comprises: first, separating the feed stream in a first separator to form a first stream having substantially all of the propane and heavier hydrocarbons and carbon dioxide and ethane and a second stream, having methane, carbon dioxide and ethane; separating the second stream in a second separator into a stream of carbon dioxide product and a third stream having ethane, methane and carbon dioxide: mixing at least a portion of the third stream with a polar compound; stream after the mixing in an absorber; separating the vapor and liquid of the third stream after the mixing in an absorber; absorbing the remaining unabsorbed carbon dioxide in a lean portion of the polar compound in the absorber, the absorber carbon dioxide and ethane with the ...
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 ...
Faserbewehrter Beton wird heute zunehmend auch bei Tunnelbauwerken (Tunnelinnenschalen, Tubbinge) eingesetzt. Wesentliche Vorteile sind das hohe Tragvermogen, das daraus entstehende Einsparungspotential an herkommlicher stabformiger Bewehrung (Biegebewehrung, Bugelbewehrung in der Randzone), die Aufnahme von Spaltzugbeanspruchungen durch die Fasern, Rissbreitenbegrenzung, erhohte Dauerhaftigkeit, verbesserter Brandwiderstand (insbesondere bei Verwendung von Kunststofffasern), Optimierung der Arbeitsablaufe etc. Neue Entwicklungen in der Betontechnologie haben in den letzten Jahrzehnten den faserbewehrten ultrahochfesten Beton (engl. UHPFRC - Ultra High Performance Fibre Reinforced Concrete) hervorgebracht. Im Rahmen dieser Arbeit wird der Einsatz des ultrahochfesten, stahlfaserbewehrten Be...
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...
A programme to optimize the short-term operation planning of hydrothermal system scheduling is presented. Based on heuristics, an operational planning of pumped storage plants and a method for fast evaluations of spot market deals under consideration of load forecast errors was developed. (orig.) [German] Vorgestellt wird ein Programm, das - basierend auf Heuristiken - den kurzfristigen Einsatz eines hydrothermischen Kraftwerksparks optimiert. Im Programm wurde dazu ein Verfahren zur Pumpseichereinsatzplanung und zur sekundenschnellen Bewertung von Spot-Markt-Geschaeften unter Beruecksichtigung von Lastprognosefehlern entwickelt. (orig.)
Elektrochemische Potentialmessungen (auch Potentialfeldmessungen) haben sich seit Jahren bewahrt, Bereiche mit aktiver chloridinduzierter Korrosion an tausalzexponierten Bauwerken, wie z. B. Bruckentafeln sowie Zwischendecks und Bodenplatten von Parkhausern und Tiefgaragen nachzuweisen. Bereits 1990 erschien die erste Fassung des Merkblatts B3 der DGZfP. Das DAfStb Heft 422 (1991) - Prufung von Beton Empfehlungen und Hinweise zu DIN 1048 - enthielt die Potentialfeldmessung bzw. das Merkblatt B3 im Anhang. In Deutschland liegen somit zwei Jahrzehnte Erfahrungen mit den entsprechenden Regelwerken und naturlich auch in der praktischen Anwendung vor. In der Praxis zeigte sich jedoch auch, dass die Anwendung verbessert werden muss. Die Potentialmessung wurde vielfach sogar falsch durchgefuhrt, ...
Apart from condensing the off-air condensers have a number of additional functions, which have been added more or less incidentally as development progressed. Advanced development of certain types of turbine condensers justifies the hope that these additional functions can be improved as power plants become cheaper and simpler.(orig.) [German] Kondensatoren haben neben ihrer Hauptaufgabe, der Kondensation des Turbinenabdampfes eine Reihe zusaetzlicher Funktionen, die sich z.T. im Laufe der Entwicklung eher beilaeufig ergeben haben. Der hohe Entwicklungsstand bei bestimmten Bauarten von Turbinenkondensatoren laesst die Erwartung zu, dass im Zuge der Vereinfachung und Verbilligung von Kraftwerksanlagen 'Nebenfunktionen' verbessert werden koennen. (orig.)
Zusammenfassung Das Konzept der ?quivalenten Spannung (Vergleichsspannung) wird seit langem angewendet und hat sich bew?hrt. Ein wesentlicher Grund daf?r liegt darin, dass es u.?a. bei der Formulierung ph?nomenologischer Werkstoffmodelle weiterhilft. Von Nachteil ist, dass es weder mit physikalischen Prinzipien in Verbindung steht, noch Informationen ?ber die Mikrostruktur des Werkstoffs enth?lt. Trotzdem wurden zahlreiche Hypothesen zur Formulierung von ?quivalenten Spannungen in der Vergangenheit aufgestellt und in der Praxis mit unterschiedlichem Erfolg angewendet. Als Basis f?r die Systematisierung der zahlreichen Modelle hat Yu die Unified Strength Theory (UST) vorgeschlagen. Diese eignet sich, u.?a. inkompressibles inelastisches Materialverhalten sowie kompressible Werkstoffe mit unt...
Automatic ultrasonic testing is presented as a method for recurrent inspections of pressure gas vessels, from validation to practical testing to customised test applications. National and international regulations and standards are presented along with related implementation problems. [German] Es wird die automatisierte Ultraschallpruefung im Bereich der wiederkehrenden Pruefung von Druckgasbehaeltern, als Alternative zur herkoemmlichen, klassischen Wasserdruckpruefung, vorgestellt. Von der Validierung ueber die praktische Erprobung bis hin zur kundenspezifisch entwickelten Pruefapplikation. Es werden die Anforderungen aus nationalen und internationalen Vorschriften und Normen sowie die damit zusammenhaengenden Umsetzungsprobleme behandelt.
The following subjects were discussed at the conference: Stability of welded joints, creep stress in CrMo steels, life prediction, developments in modern power plant steels, testing, calculation of deformation, crack propagation and crack analysis under complex loads. [German] Die Autoren der Tagung referieren ueber folgende Themen: Stabilitaet von Schweissverbindungen, Kriechbeanspruchung von Chrom-Molybdaen Staehlen, Lebensdauervorhersage, Entwicklungen fuer die Anwendung in modernen Kraftwerken, Prueftechnik, Berechnung von Verformung, Rissentwicklung und -bewertung bei komplexer Beanspruchung. (uke)
The present thesis presents two different aspects of my work in the L3 experiment, which are on one side the search for supersymmetric particles, the scalar leptons, in two different topologies 'electron + X + E' and '2 leptons + 2 photons + E', each of them being related to two theoretical SUSY models, m-SUGRA and GMSB. On the other side my work has been completed by the study of the BGO crystal electromagnetic calorimeter of L3, and the calibration of the electromagnetic calorimeter EGAP. After the essential motivations being reviewed, the production and disintegration modes are detailed concerning the scalar lepton sector at LEP. Then one presents the analysis techniques which I used to perform my selection, and also the results obtained from the data collected by L3 for center of mass energies between {radical} S =183 GeV and 202 GeV. The selection criteria that allow to isolate the events I looked for, ...
A unique beam of pulsed electrons has been developed using the 19-MeV, 700-kA Hermes-III accelerator. The extended planar-anode diode is used to extract at large radius an annular electron beam from the accelerator and inject the resulting beam at small angle into a low-pressure gas cell, where the beam is rapidly charge neutralized and almost current neutralized. Under these conditions, the beam propagates nearly ballistically to a focus downstream of injection, where objects can be placed for irradiation and study. For a focal length of 78 cm, measurements with a segmented calorimeter show that this configuration can deliver an energy deposition of 200 J/g [20 Mrad] over a useful area of 70 cm{sup 2} and a 4-cm depth in graphite in 25 ns. Increasing the injection angle by reducing the AK gap permits higher doses over smaller areas to be achieved. Such beams are of interest for the study of material property changes from short-pulse high-energy depositions and for ...
International standards and guidelines for calibrating high-dose dosimetry systems to be used in industrial radiation processing recommend that dose-rate effects on dosimeters be evaluated under conditions of use. This is important when the irradiation relies on high-current electron accelerators, which usually provide very high dose-rates. However, most dosimeter calibration facilities use low-intensity gamma radiation or low-current electron accelerators, which deliver comparatively low dose-rates. Because of issues of thermal conductivity and response, portable calorimeters cannot be practically used with high-current accelerators, where product conveyor speeds under an electron beam can exceed several meters per second and the calorimeter is not suitable for use with product handling systems. As an alternative, Monte Carlo calculations can give theoretical estimates of the absorbed dose in materials with flat or complex configurations such ...
Thermodynamic consideration and process calculations at equilibrium conditions showed that processes for separating gas mixtures by partial condensation at low temperatures using turboexpanders have got less energy losses than processes with quasi isobar partial condensation. Compared to the low-pressure parts of condensing steam turbines in turboexpanders less erosion problems are to expected for such separating processes. Separation of liquid in the machine, however, is more difficult withouf additional measures. (orig.).
The possibility of separation in plasma-mass-separator POMS-E-3 spent nuclear fuel (SNF) in 3 fractions: transuranic elements, and two groups of fission products. New scheme of compact energy-mass analyzer for monitoring the separation process spent nuclear fuel in the POMS-E- 3 offered.
A radiochemical method of separation of {sup 203}Hg from {sup 181}Hf is described. The method involves separation by Dowex 50W- X 8, 100-200 mesh, cation exchange resin using 1 M hydrochloric acid as the eluant. The chemical yield for the separation of mercury is > 85% and the decontamination factor is >10{sup 4}. The {sup 181}Hf can be eluted from the column by 4 M HCl.
Nuclear forensic science has become increasingly important for global nuclear security. However, many current laboratory analysis techniques are based on methods developed without the imperative for timely analysis that underlies the post-detonation forensics mission requirements. Current analysis of actinides, fission products, and fuel-specific materials requires time-consuming chemical separation coupled with nuclear counting or mass spectrometry. High-temperature gas-phase separations have been used in the past for the rapid separation of newly created elements/isotopes and as a basis for chemical classification of that element. We are assessing the utility of this method for rapid separation in the gas-phase to accelerate the separations of radioisotopes germane to post-detonation nuclear forensic investigations. The existing state of the art for thermo chromatographic ...
The project is intended to yield information on the transfer factors describing the transfer of ingested radionuclides to breast milk for the following elements: antimony, cerium, chromium, cobalt, gallium, lanthanum, molybdenum, niobium, radium, ruthenium, silver, thorium, titanium, and uranium. Those yet unknown or poorly known transfer factors are required in order to be able to develop a reliable model for description and assessment of the transfer of the radionuclides and the possibly resulting hazardous doses to infants, and for subsequent formulation of recommendations for radiological protection of the population. (orig./CB) [German] Ziel des Projektes ist die Ermittlung von Transferfaktoren fuer den Uebergang von Radionukliden aus der Nahrung der Muetter in die Muttermilch fuer die Elemente Antimon, Cer, Chrom, Cobalt, Gallium, Lanthan, Molybdaen, Niob, Radium, Ruthenium, Silber, Thorium, Titan und Uran. Um die Exposition und damit die ...
The stirling cryocooler ILK 15 is a machine with simple drive concept. This machine works with a conventional built-in electric motor and crank drive and needs a power input of about 500 W. The refrigerating capacity is 15 W at 80 K with a cooldown time of 12 minutes. The cooler is somehow a replacement for the Gifford-McMahon cycle coolers, which are bigger and heavier. The Stirling cryocooler was designed to cool HTSC-components. (orig.) [Deutsch] Der Stirlingkuehler ILK 15 ist eine Kaeltemaschine mit einfachem Antriebskonzept. Die Maschine arbeitet mit einem konventionellen Elektroeinbaumotor und Kurbeltrieb. Sie benoetigt eine Antriebsleistung von 500 W und hat eine Kaelteleistung von 15 W bis 80 K und eine Einkuehlzeit von 12 Minuten. Die Maschine kann als Alternative zur wesentlich groesseren und schweren Gifford-McMahon-Maschine gesehen und bei der Kuehlung von HTSL-Komponenten eingesetzt werden. ...
The danger potential for 110 kV cables, which are installed on racks and in tunnels, caused by catching fire because of arcing short circuits and mechanical overstressing by peak shortcircuit current, has been experimental analysed under Bewag network conditions. As a result, recommendations for an improved installation of 110 kV cables are given. (orig.) [Deutsch] Fuer offen gelegte 110-kV-Kabel in Raeumen, auf Fussboeden und in Schaechten wurde das von Kurzschluessen auf den Kabeln ausgehende Gefaehrdungspotential fuer die Entstehung von Kabelbraenden durch Fehlerlichtboegen und fuer eine mechanische Ueberbeanspruchung von Kabeln durch Stosskurzschlussstroeme unter Beruecksichtigung der Netzverhaeltnisse der Bewag experimentell untersucht. Im Ergebnis geben die Verfasser Empfehlungen fuer die sichere Anordnung offen gelegter 110-kV-Kabel. (orig.)
The article presents measures for the solution of construction-biological problems and for reducing the pollutant load of buildings. (HW) [Deutsch] Der Artikel berichtet ueber Massnahmen ueber Sanierung von baubiologischen Schwachstellen und Schadstoffbelastungen in Gebaeuden. (HW)
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. ...
The picture of wind energy parks at the German North Sea Coast is well-known. There are also some of them on the Northern Friesian Islands. Recently, however, biogas plants have been conquering the western coast of Schleswig-Holstein, starting from the continent.
The applicability of isothermal solidification as a contacting method for solar cells was proved for the systems AgSn and AuIn. The process is advantageous in that it requires no fluxes, no inert gases, and no pretreatment of the components. The IE contac...
The authors shortly describe some basic aspects relating to probabilistic reliability calculation and to the derivation of component reliability data. (GL)
Under the new name of ``geothermal heat pump``, ground-source heat pumps are currently high in demand in Northern America. In sectors characterized by heating and cold air demand, their advantages can be exploited to the full. For Germany, the end-use-energy substitution potential of geothermal heat pumps has been estimated at 1310-1470 PJ annually. Whether this potential can actually be exploited depends essentially on the development of energy prices, but also on the resourcefulness of plant and heat pump manufacturers in upgrading and cheapening geothermal heat pumps. (orig./RHM) [Deutsch] Unter der neuen Bezeichnung `Geothermal Heat Pump` erlebt die erdgekoppelte Waermepumpe z.Zt. in Nordamerika einen Verbreitungsschub. In dem durch Heiz- und Kuehlbedarf charakterisierten Umfeld kann sie Ihre Vorteile voll nutzen. Fuer Deutschland kommt eine Schaetzung zu einem Potential der erdgekoppelten Waermepumpen zur Substition von Endenergie von ...
The report deals with the energy consumption of traffic and its emissions of hazardous substances into the air, and stresses the advantages of the electric car with respect to energy consumption and noise generation. 5 figs., 3 refs.
This article describes the processes for the treatment of plastic waste: sampling, sorting, comminution. The requirements for the different processes for waste treatment (as recycling, utilization as raw material, energy recovery, combustion) are listed. (SR)
A report is given of investigations into the possibility of utilizing red mud from the Bayer process for producing Ferrari cements. On repeated burning at 1450deg C suitable mixtures of red mud with silica and lime form a clinker with a low free lime content from which Ferrari cement can be produced. The average 28-day compressive strengths of cements produced from this clinker are so encouraging that further investigations are appropriate. (orig.).
The amended Radiation Protection Ordinance of 2001 contains regulations on natural radioactive materials, whose recycling or disposal poses practical problems. There is little experience in this field so far. [German] Die novellierte Strahlenschutzverordnung von 2001 befasst sich auch mit natuerlich vorkommenden radioaktiven Stoffen. Bei ihrer Verwertung oder Beseitigung ergeben sich praktische Fragen, die beachtet werden muessen. Erfahrungen auf diesem Gebiet liegen bisher kaum vor. (orig.)
1. Cyanide degradation: Of the cyanide- and thiocyanate-degrading bacteria, Burkholderia cepacia and Pseudomonas spec. were the most effective. 2. Biosorption: Of the isolates suited for biosorption of heavy metals, 597-A (non-identifiable) and 597-A2 (Aspergillus fumigatis) had the biggest potential. The sorption capacity of the fungi for metals varied with the C source used for their growth: apple juice > molasses > glucose. The fungi are not cyanide-sensitive and can even degrade cyanide. Living biomass had better metal sorption efficiencies than dead mycelium. The biosorption rates in waste water were usually higher than in broth. Depending on the metal composition and concentrations and on the exposure time and volume of the mycelia, up to 85 % of the initial concentration was removed from the liquid phase. The capacity of different biomasses for the sorption of metal mixtures was between 65 and 80 mg/g of dry matter depending on the experimental conditions, with ...
It is reported about the adsorptive stripping voltammetric determination of uranium, antimony, tin, vanadium and molybdenum using chloranilic acid as complex forming reagent. The determination limits are in the l{sup 1}-range. (orig.) [Deutsch] Es wird ueber die Bestimmung von Uran, Antimon, Zinn, Vanadium und Molybdaen durch Adsorptions-Stripping-Voltammetrie mit Chloranilsaeure als Komplexbildner berichtet. Die Bestimmungsgrenzen liegen im ng l{sup -1} Bereich. (orig.)
In this project the influence of residual compression stresses on the stress corrosion cracking behaviour of the turbine disc steel 26 NiCrMoV 14 5 (Rp(sub 0.2) = 850 N/mm(sup 2)) was investigated. The residual compression stresses were produced by shot p...
The evaluation of possible manufacture-based defects in turbine shafts and housings for component serviceability relevance is of particular interest not only in post-manufacturing NDT but also in evaluation of NDT results obtained by in-service inspections of components with long service lives. The results discussed in the paper are summarized as follows: Most of the examined natural defects in the forgings and castings behave like cracks under the simulated operating conditions and hence may well be evaluated by fracture mechanical methods for their serviceability relevance determined by crack propagation under fatigue, creep and creep-fatigue stress. The empirical correlation of true defect size and US testing results (echo signal, echodynamics, attenuation) permits improved determination of true defect sizes in the turbine components. Care has to be taken to select the proper testing and evaluation methods in compliance with defect types. (orig./MM) [Deutsch] Die ...
This paper reports that only a few years ago superconducting magnetic separation was viewed as the next major market for superconducting magnets. The first commercial units had been installed, worked flawlessly, and demonstrated real economic viability. The potential market was seen as quite large, and many people believed that superconducting magnetic separation would soon show the same rapid growth that MRI had demonstrated after its initial success. These hopes even prompted IGC, one of the top MRI magnet builders, to form a separate division devoted to magnetic separation. Despite the existence of Magstream, IGC has not been overly active in the market. As a technology that has applications from the clay on the Earth to the soil on the moon, superconducting magnetic separation has yet to become widely used.
This research project aimed to determine the factors for the transfer of the elements silver (Ag), cerium (Ce), cobalt (Co), chrome (Cr), gallium (Ga), lanthanum (La), molybdenum (Mo), niobium (Nb), radium (Ra), ruthenium (Ru), antimony (sb), thorium (Th), titanium (Ti) and uranium (U) from food into the mother's milk. This factors will be used as a basic to check and derive activity values for the contamination of food and for radiation protection at working places of suckling women. For this purpose 19 mothers collected samples daily (2-8 weeks), using the duplicate method, of all the food they consumed as well as of their milk. After microwave-assisted digestion the element contents were analysed by mass-spectroscopy with inductive coupled plasma (ICP-MS). The results of the mothers who participate for more than 5 weeks were used to make a time lapse between the intake and transfer of the elements in the mothers milk visible. (orig.) [German] Ziel dieses Forschungsvorhabens ...
The precipitation hardened, ferrite-pearlite medium-carbon steels microalloyed with vanadium (AFP steels) have been developed over the last few years as materials allowing processing by controlled, continuous cooling down from forging temperatures, for achieving benefits such as reducing the number of required heat treatment and working processes and saving expensive alloying materials. Due to their cost-saving advantages, the steels rapidly have been accepted as an alternative material to the quenched and tempered steels and re particularly used for fabrication of automobile parts. Their drawbacks however are the lower yield strength, and low ductility and toughness as compared to the heat-treatable steels. The research project therefore was intended to enhance the properties of the microalloyed, medium-carbon steels and widen their applicability by establishing further and improving existing thermomechanical treatment processes that will considerably improve the steels` strength and ...
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 ...
A one-nanometer scale transmission electron microscope electron probe X-ray microanalysis characterization of as-deposited and annealed aluminum--11.5 at.% zirconium multilayer samples in cross-section synthesized by magnetron sputtering is reported on here. Composition line profiles were acquired across Zr layers in as-deposited material and samples isochronally annealed in a differential scanning calorimeter to temperatures of 290 C and 485 C. A spatial resolution of approximately 1.5 to 2.0 nm was achieved in these experiments and will be improved by deconvolution of the instrumental electron probe function from the data. The as-deposited structure consisted of crystalline Al and Zr layers with thin amorphous layers at the Al/Zr interfaces. The amorphous interface layers increased in thickness upon annealing to 290 C. Additionally, at 290 C a metastable cubic alloy forms at the Zr deposited on Al interface. Upon heating to 485 C a multilayer of Al and metastable ...
The important amount of hydration water in the ulexite (NaCaN{sub 5}O{sub 9}.8H{sub 2}O), allows using calcination methods to increase its B{sub 2}O{sub 3} content. This paper analyses the thermal decomposition reaction of a preconcentrated ulexite through weight loss measurements, which occur during the heating of samples until 1000 degree centigree, Determinations of heat content at each temperature were made using an isoperibol calorimeter. The mean specific heat was calculated from these values, and its dependence on temperature was determined. The maximum weight loss was about 32.5% and the specific heat obtained was 1,13 kJ/kg 0 C for solid samples and 1,38 kJ/kg''0 C for fluid samples. The results are useful for the design of the industrial process, in order to determine the thermal requirements for heating calcined ulexite, and to obtain smelted ulexite. (Author) 19 refs.
In an adiabatic low-pressure calorimeter, the temperature dependence of the standard molar heat capacity of paramagnetic dicarbonyl rhodium complex with o-semiquinone (CO){sub 2}Rh(SQ) has been determined in the range from T=(6 to 355)K mainly with an accuracy of about 0.3%. Over the ranges from T=(205 to 234) K, T=(266 to 315)K and T=(316 to 345)K physical transformations have been revealed and their enthalpies and entropies have been estimated. The experimental data were used to calculate the thermodynamic functions C{sub p,m}{sup o}/R,{delta}{sub 0}{sup T}H{sub m}{sup o}/(R.K),{delta}{sub 0}{sup T}S{sub m}{sup o}/R and {phi}{sub m}{sup o}={delta}{sub 0}{sup T}S{sub m}{sup o}-{delta}{sub 0}{sup T}H{sub m}{sup o}/T (where R is the universal gas constant) between T=(0 and 355)K. The fractal dimension D in the heat capacity function of the fractal variant of Debye heat capacity theory has been evaluated.
The existing Tokamak Fusion Test Reactor Neutral Beam system is proposed to be modified for long pulse operation on the Tokamak Physics Experiment (TPX). Day one of TPX will call for one TFTR beamline modified for 1000 second pulse lengths oriented co-directional to the plasma current. The system design will be capable of accommodating an additional co-directional and a single counter directional beamline. For the TPX conceptual design, every attempt was made to use existing Neutral Beam hardware, plant facilities, auxiliary systems, service infrastructure, and control systems. This paper describes the moderate modifications required to the power systems, the ion sources, and the beam impinged surfaces of the ion dumps, the calorimeters, the various beam scrapers, and the neutralizers. Also described are the minimal modifications required to the vacuum, cryogenic, and gas systems and the major modification of replacing the beamline-torus duct in its entirety. ...
We propose to investigate the in-medium properties of vector $\\omega$ mesons at the normal nuclear density in Ap(pA) collisions and at higher density in AA collisions at the ITEP accelerator facility TWAC. Using of the inverse Ap kinematics will permit us to study the $\\omega$ meson production in a wide momentum interval included the not yet explored range of small meson momenta relative to the projectile nuclei where the mass modification effect in nuclear matter is expected to be the strongest. Momentum dependence of the in-medium $\\omega$ meson width will be studied in the traditional pA kinematics. We intend to use the electromagnetic calorimeter for reconstruction of the $\\omega$ meson invariant mass by detecting photons from the $\\omega \\to \\pi^{0}\\gamma \\to 3\\gamma$ decay. The model calculations and simulations with RQMD generator show feasibility of the proposed experiment. Available now intensity of the ion beams provides a possibility to collect ...
In future collider experiments, where a background radiation level is estimated to be very high, e.g. around 10"2 #approx# 10"5 Gy/yr and 10"1"1 #approx# 10"1"4 n/cm"2/yr at SSC, the detectors operating around the collision point in the experiments will encounter a considerable amount of radiation. Therefore, the detectors, especially the calorimeter, are required to be resistive against high radiation levels. From this point of view, it is of great importance to study the effects of radiation damage on the performance of the detectors. The authors report preliminary results of measurements of radiation hardness of the plastic scintillating fiber Kuraray SCSF-81 against irradiation with fast neutrons and "6"0Co #gamma#-rays in the region of the neutron fluence from 1 x 10"1"1 to 5 x 10"1"3 n/cm"2 and the integrated #gamma#-ray dose from 890 to 10"5 Gy, respectively. Deterioration of both intrinsic light yield and light transmittance of the SCSF-81 has been studied.
A thermal analyzer-differential scanning calorimeter-mass spectrometer (TG-DSC-MS) was used to study oxygen carriers (OC) for their potential use for the application of chemical looping combustion (CLC) to solid fuels. Reaction rates, changes in reaction rates with repeated oxidation-reductions, exothermic heats during oxidation, and the effect of changing reduction gas compositions were studied. Oxidation rates were greater than reduction rates and reaction rates were reproducible through multiple oxidation-reduction cycles except where agglomeration occurred with powders. Iron oxide (Fe{sub 2}O{sub 3} powder) and iron-based catalysts were found suitable for CLC of solid fuels having rapid reduction rates which increased with higher reducing gas concentrations. Fe{sub 2}O{sub 3} powder was used to oxidize a high carbon coal char in an inert gas removing 88% of the carbon from the char. Other properties such as cost and durability indicated iron oxide OCs potential ...
The presented results are the first measurements at RHIC for direct $\\gamma$-charged hadron azimuthal correlations in heavy ion collisions. We use these correlations to study the color charge density of the medium through the medium-induced modification of high-p$_T$ parton fragmentation. Azimuthal correlations of direct photons at high transverse energy (8 $<$ p$_T$ $<$ 16 GeV) with away-side charged hadrons of transverse momentum (3 $<$ p$_T$ $<$ 6 GeV/c) have been measured over a broad range of centrality for $Au+Au$ collisions and $p+p$ collisions at $\\sqrt{s_{NN}}$ = 200 GeV in the STAR experiment. A transverse shower shape analysis in the STAR Barrel Electromagnetic Calorimeter Shower Maximum Detector is used to discriminate between the direct photons and photons from the decays of high p$_T$ $\\pi^{0}$. The per-trigger away-side yield of direct $\\gamma$ is smaller than from $\\pi^{0}$ trigger at the same centrality class. Within the current ...
In the microwave tokamak experiment (MTX) program, we are concentrating on experiments using intense, free-electron laser (FEL) generated microwave pulses. In initial FEL experiments, several diagnostic instruments were operated during injection of microwave pulses with peak powers to 0.2 GW at durations of 10 ns. Fixed and spatially scanning microwave detectors and receivers and a 48-element calorimeter on the inside wall of MTX diagnosed the GW-level FEL microwave pulses. With these diagnostics, linear-wave absorption and efficiencies of transmission through the quasi-optical transport system were studied. In addition, several radially resolved measurements of plasma density, temperature, and emission were made during FEL injection and were used in the analysis of microwave absorption data. A timing system, slaved to the FEL pulse arrival time, is capable of accuracy to a few nanoseconds in order to allow measurement of heating effects on the time scale of a ...
Investigations of the properties of absorbed monolayers have received great experimental and theoretical attention recently, both because of the importance of surface processes in practical applications such as catalysis, and the importance of such systems to the understanding of the fundamentals of thermodynamics in two dimensions. We have adapted the composite bolometer technology to the construction of microcalorimeters. For these calorimeters, the adsorption substrate is an evaporated film deposited on one surface of an optically polished sapphire wafer. This approach has allowed us to make the first measurements of the heat capacity of submonolayer films of /sup 4/He adsorbed on metallic films. In contrast to measurements of /sup 4/He adsorbed on all other insulating substrates, we have shown that /sup 4/He on silver films occupies a two-dimensional gas phase over a broad range of coverages and temperatures. Our apparatus has been used to study the heat ...
Enthalpy increment measurements on La{sub 2}Te{sub 3}O{sub 9}(s) and La{sub 2}Te{sub 4}O{sub 11}(s) were carried out using a Calvet micro-calorimeter. The enthalpy values were analyzed using the non-linear curve fitting method. The dependence of enthalpy increments with temperature was given as: H{sup o}(T) - H{sup o}(298.15 K) (J mol{sup -1}) = 360.70T + 0.00409T {sup 2} + 133.568 x 10{sup 5}/T - 149 923 (373 {<=} T (K) {<=} 936) for La{sub 2}Te{sub 3}O{sub 9} and H{sup o}(T) - H{sup o}(298.15 K) (J mol{sup -1}) = 331.927T + 0.0549T {sup 2} + 29.3623 x 10{sup 5}/T - 114 587 (373 {<=} T (K) {<=} 936) for La{sub 2}Te{sub 4}O{sub 11}.
Enthalpy increment measurements on La_2Te_3O_9(s) and La_2Te_4O_1_1(s) were carried out using a Calvet micro-calorimeter. The enthalpy values were analyzed using the non-linear curve fitting method. The dependence of enthalpy increments with temperature was given as: H"o(T) - H"o(298.15 K) (J mol"-"1) = 360.70T + 0.00409T "2 + 133.568 x 10"5/T - 149 923 (373 #<=# T (K) #<=# 936) for La_2Te_3O_9 and H"o(T) - H"o(298.15 K) (J mol"-"1) = 331.927T + 0.0549T "2 + 29.3623 x 10"5/T - 114 587 (373 #<=# T (K) #<=# 936) for La_2Te_4O_1_1.
The total hemispherical emittance of an oxide film that formed on 6061-T6 aluminium alloy parts in the Tower Shielding Reactor-II at Oak Ridge National Laboratory was measured from 295 to 773 K using an emissometer and/or a calorimeter. The emittance of this film was critically needed for heat transfer calculations in a simulated loss-of-coolant accident of the reactor. X-ray diffraction analysis identified the film as boehmite (Al{sub 2}O{sub 3} {times} H{sub 2}O), which dehydrated to alumina (Al{sub 2}O{sub 3}) upon heating above 473 K. The measured emittances for the alumina film are in excellent agreement with published values for anodized aluminum films and for bulk alumina. Published values of the emittance of boehmite could not be found for comparison, but evidence is presented that some anodization processes for aluminum yield boehmite and not alumina films.
ECAL Barrel (EB) As already mentioned in June, the Barrel ECAL is fully commissioned and routinely used during CRUZET runs. Good progress has been made in the last months to ensure a stable and fully reliable operation, in particular for the Trigger path. More details can be found in the DPG report in this bulletin. ECAL Endcaps (EE) In the June CMS bulletin, it had been announced that the Dee’s mechanical assembly had been finished end of May. However the electronics integration was still going on for the first Dee. The Summer has seen a spectacular breakthrough of the Endcap project. The electronics integration of Dee1 was completed early July, and this first Dee was transported to point 5 on July 8th. The completion of the three other Dees followed at a pace of one per week. In all cases the quality of the detector as measured in the assembly center was excellent, with all channels active and the expected noise performance (see ...
This report describes the combustion experiments performed using the SP Industry Calorimeter. In addition to measuring parameters such as heat release rate (HRR), mass loss rate, effective heat of combustion and smoke obscuration, considerable effort was put into the characterisation of the smoke gases in order to obtain a basis for evaluations of the toxic potency of the smoke. The materials studied were Nylon 66, polypropene, polystyrene (with and without fire retardant, respectively), PVC and chlorobenzene. A total of 19 large-scale, well ventilated combustions were carried out. The mass of sample burned ranged from 20 kg to 125 kg in an experiment. A procedure was designed for cleaning the smoke gas duct between experiments and was found to be effective. Measurements were carried out for the amounts of O{sub 2}, CO{sub 2}, CO, NO{sub x}, THC (unburned hydrocarbons), HCN, HCl, NH{sub 3} and individual organic compounds in the smoke. Adsorbents were used for the ...
In Sweden, spent nuclear fuel will be encapsulated and placed in a deep geological repository. In this procedure, reliable and accurate spent fuel data such as discharge burnup, cooling time and residual heat must be available. The gamma scanning method was proposed in earlier work as a fast and reliable method for the experimental determination of such spent fuel data. This thesis is focused on the recent achievements in the development of a pilot gamma scanning system and its application in measuring spent fuel residual heat. The achievements include the development of dedicated spectroscopic data-acquisition and analysis software and the use of a specially designed calorimeter for calibrating the gamma scanning system. The pilot system is described, including an evaluation of the performance of the spectrum analysis software. Also described are the gamma-scanning measurements on 31 spent PWR fuel assemblies performed using the pilot system. The results obtained ...
In Sweden, spent nuclear fuel will be encapsulated and placed in a deep geological repository. In this procedure, reliable and accurate spent fuel data such as discharge burnup, cooling time and residual heat must be available. The gamma scanning method was proposed in earlier work as a fast and reliable method for the experimental determination of such spent fuel data. This thesis is focused on the recent achievements in the development of a pilot gamma scanning system and its application in measuring spent fuel residual heat. The achievements include the development of dedicated spectroscopic data-acquisition and analysis software and the use of a specially designed calorimeter for calibrating the gamma scanning system. The pilot system is described, including an evaluation of the performance of the spectrum analysis software. Also described are the gamma-scanning measurements on 31 spent PWR fuel assemblies performed using the pilot system. The results obtained ...
Apparent molar volumes V{sub phi} and apparent molar heat capacities C{sub p,phi} were determined for aqueous solutions of nickel(II) nitrate, copper(II) nitrate, and zinc(II) nitrate at molalities m=(0.01 to 0.5) mol {center_dot} kg{sup -1}, and at the pressure p=0.35 MPa. Solution densities obtained using a vibrating-tube densimeter at T=(278.15 to 368.15) K were used to calculate V{sub phi} values. Heat capacity measurements obtained with a twin fixed-cell, differential-output, power-compensating, temperature-scanning calorimeter at T=(278.15 to 393.15) K were used to calculate values of C{sub p,phi}. Our results were then fitted to functions of m and T and compared to literature values.
A new measurement of the cosmic ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. PAMELA is equipped with a silicon-microstrip magnetic spectrometer and a silicon-tungsten imaging calorimeter and has been collecting data since July 2006. During 500 days of data collection a total of about 1000 antiprotons have been identified, including 100 above an energy of 20 GeV. The high-energy results are a ten-fold improvement in statistics with respect to all previously published data. The antiproton-to-proton flux ratio increases smoothly with energy up to about 10 GeV, in agreement with previous experiments, and then levels off. The data follow the trend expected from secondary production calculations and significantly constrain contributions from exotic sources, e.g. dark matter particle annihilations.
Lithium isotope separation by displacement chromatography is studied using fundamental principles; the equations are derived assuming theoretical stages in lithium adsorption bands. The concentration profiles in the band are calculated numerically under unsteady state.
The chloroplast and cytoplasmic isoenzymes of phosphoglycerate kinase (PGK) (EC. 2.7.2.3) from Hordeum vulgare leaves have been separated and purified for the first time to apparent...Full Text Available
Separate abstracts were prepared for 60 papers in this volume of conference proceedings. None other papers in the proceedings were previously abstracted for EDB. Also included in the proceedings but not indexed separately are six workshop summaries and a session introduction. (LEW)
The long-term impact of early stress on behavior and emotions is well documented in humans, and can be modeled in experimental animals. In mice, maternal separation during early postnatal development...Full Text Available
A pretreatment flowsheet was tested for separating key radionuclide components from the sludge stored in one of the high level waste tanks (B-110) at the Hanford Site; this sludge resulted primarily from the bismuth phosphate process, which was one of the three major plutonium separation processes used at Handford. This test involved (1) washing with water, (2) caustic leaching, (3) acid dissolution, (4) separation of transuranic elements (TRUs) by extraction with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), (5) separation of Sr by extraction with di-t-butylcyclohexano-18-crown-6, (6) separation of Cs from the acid-dissolved sludge solution by treatment with ammonium molybdophosphate (AMP), and (7) separation of Cs from the sludge wash and caustic leach solutions by ion exchange using a phenol-formaldehyde resin (CS-100). The results of the ...
The primary method for neuronal communication involves the extracellular release of small molecules that are packaged in secretory vesicles. We have developed a platform to separate, lyse, and...Full Text Available
This thesis describes the analysis of the semileptonic decay D{sup 0} {yields} {bar K}{sup 0} {pi}{sup -} {mu}{sup +}{nu} using FOCUS data. FOCUS is a fixed target experiment at Fermilab that studies the physics of the charm quark. Particles containing charm are produced by photon-gluon fusion from the collision of a photon beam on a BeO target. The experiment is characterized by excellent vertex resolution and particle identification. The spectrometer consists of three systems for track reconstruction (two silicon systems and one multiwire proportional chamber system) and two magnets of opposite polarity. The polarity of the magnet is such that the events of e{sup +}e{sup -} pairs produced in the target (which constitutes the main background) travel through a central opening in the detectors without interactions. Particle momentum is measured from the deflection angle in the magnets. Three multicell Cerenkov counters are used for charged particle identification (for e, {pi}, K, and ...
Apparatus and method for selective measurement of tritium oxide in an environment which may include other radioactive components and gamma radiation, the measurement including the selective separation of tritium oxide from a sample gas through a membrane into a counting gas, the generation of electrical pulses individually representative by rise times of tritium oxide and other radioactivity in the counting gas, separation of the pulses by rise times, and counting of those pulses representative of tritium oxide. The invention further includes the separate measurement of any tritium in the sample gas by oxidizing the tritium to tritium oxide and carrying out a second separation and analysis procedure as described above.
comprehensive description for this model is available through AGARD, Reference [8]. ... Specifically, there is a pocket of flow separation at the side-of- body ...
... PRC's President Jiang Zemin promised, under all circumstances and despite political differences, to protect fully Taiwanese business interests on ...
... of drag measurements with the AGARD Nozzle Afterbody ... are discussed separately from flows with a ... bubbles introduce typical flow phenomena that ...
Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of antibiotics in wastewater.
... 65th AGARD Fluid Dynamics Symposium, Madrid, Spain, October ... of research programs on flow control ... separation, and delta wing flows formed the ...
The effects of temperature and the use of macroreticular resins were studied in lithium isotope separation by an ion-exchange method. The isotope separation factors obtained decreased by increasing the temperature, and the factors for macroreticular resins were identical with those for the usual gel-type resins. However, the performance of isotope separation per unit band length in displacement chromatography was found to be improved by increasing the temperature and using macroreticular resins, because accelerating the interphase mass transfer caused the reduction of HETP (Height Equivalent to a Theoretical Plate).
Group for Aerospace Research and Development (AGARD) symposium and continue to ...... of vertical structures and flow separation within the tip, platform, ...
Separation of lithium isotopes was investigated by chemical ion exchange with a hydrous manganese(IV) oxide ion exchanger using an elution chromatography. The capacity of manganese(IV) oxide ion exchanger was 0.5 meq/g. The heavier lithium isotope was enriched in the solution phase, while the lighter isotope was enriched in the ion exchanger phase. The separation factor was determined according to the method of Glueckauf from the elution curve and isotopic assays. The separation factor of {sup 6}Li{sup +} -{sup 7}Li{sup +} isotope pair fractionation was 1.018.
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 ...
Numerous task forces at universities, other research institutions and in industry have been concerned with the development of methods fit to replace animal experiments. A great many useful in-vitro test systems were developed. From 1986 to 1993 the ``In-vitro Systems`` newsletter was published with the support of the federal ministry of science and technology. Its purpose was to intensely promote the concept of in-vitro systems for the benefit of experimental animals among scientists, and to demonstrate to the public the limits of such endeavours. This brochure is a compilation of 141 contributions from all annual volumes, dealing inter alia with research projects for the development of pharmaceuticals, toxicology and quality control, ethic-philosophical considerations, meeting reports, and book reviews. Changes or revisions have not been made; so some of the contributions have been overtaken by more recent developments. (MG) [Deutsch] Viele Arbeitsgruppen an Universitaeten, anderen ...
A phenomenological model of the heat transfer in direct injection diesel engines was developed. Utilizing the thermodynamic results of a combustion model as an input, the model is able to predict the temporal variation of the heat losses from the cylinder gas to the cylinder walls. Additionally, the division into isothermal combustion chamber subsurfaces allows the consideration of the spatial variation of the wall heat fluxes. The physical mechanisms such as flow dependent convection, heat radiation due to hot soot particles and isolation effects of deposited soot layers are described in detail. Thus the effects of these mechanisms on the overall heat transfer can be studied. The heat transfer model was verified successfully by the comparison to measured wall heat fluxes in a single-cylinder direct injection diesel engine. It is shown that the effects of engine speed and load, turbocharging and soot deposition can be predicted with good accuracy. [German] Es wurde ein ...
A high-temperature flow reactor and different technical plants were tested within the framework of this research project. Anthropogenic N{sub 2}O emissions form during secondary flue gas or waste gas purification as secondary emissions during denitrification and pollution abatement measures. N{sub 2}O forms as an intermediate product as NO is reduced to N{sub 2}. Under certain operating conditions N{sub 2}O is not decomposed completely. Different secondary flue gas purification measures, i.e. selective noncatalytic reduction (SNCR), selective catalytic reduction (SCR), and nonselective catalytic reduction (NSCR) were investigated testing several technical plants and the high-temperature flow reactor. (orig./EF) [Deutsch] Das Forschungsprojekt ``Messung der N{sub 2}O-Emissionen von Verbrennungsanlagen und Untersuchung von Moeglichkeiten zur Emissionsminderung`` wurde an einem Hochtemperatur-Stroemungsreaktor und an verschiedenen technischen ...
CNG vehicles suffer from an uncontrolled temperature rise of the gas inside the tank during the filling process and heat exchange with the environment leads to variable filling levels. A partly filled tank reduces the range of CNG vehicles and works as a impediment to the spreading of environmentaly more friendly CNG vehicles. The increase of the pressure inside the tank combined with a prolongation of the filling time beyond three minutes can reduce the deficit of the filling process. For economic reasons the time required for refuelling should be as short as possible without the need to operate the filling station with a critical pressure. To meet this target the current technique requires further improvement. (orig.) [Deutsch] Die betriebliche Praxis bei Tankvorgaengen von Erdgasfahrzeugen zeigt, dass waehrend des Tankvorganges die Temperatur des getankten Erdgases im Fahrzeugtank ansteigt. Waehrend und nach Beendigung des Tankvorganges findet ein ...
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 ...
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 UO{sub 2}/ZrO{sub 2} ...
The separation, concentration, and determination of trace elements in iron ores are described. After the sample has been dissolved, the iron is separated by liquid-liquid extraction with a liquid cation-exchanger, di-(2-ethylhexyl) phosphoric acid. The trace elements aluminium, cadmium, calcium, chromium, cobalt, copper, lead, magnesium, manganese, mercury, potassium, sodium, vanadium, and zinc are determined in the aqueous phase by atomic-absorption spectrophotometry.
This document provides stakeholder evaluations on innovative technologies to be used in the remediation of volatile organic compounds from soils and ground water. The technologies evaluated are; in-well vapor stripping, in-situ bioremediation, and gas membrane separation.
Tetracycline in solution of benzyl alcohol was used as an extracting agent to separate uranium from interfering elements in the determination of uranium and of isotopic ratio sup(235)U/sup(238)U by neutron activation analysis. Separation gives a recovery of 97% for uranium and the interferences from matrices of pitchblende and monazite are eliminated.
The results of calculated and experimental investigation of interphase isotopic exchange efficiency in countercurrent columns are given when separation processes of isotope mixtures are taken place with use of liquid-solid systems. Effect of liquid phase flow on transfer unit height in ion exchange separation of boron, lithium, nitrogen isotopes is considered. 40 refs.; 5 figs.
Research highlights: #-># Red mud residues (RM) were disposed in alumina production. #-># Utilization of Red mud residues was affected by its iron content. #-># Superconducting magnetic separation (HGSMS) was used in iron separation from RM. #-># RM with high and low iron contents were separated in HGSMS. - Abstract: The disposal of bayer red mud tailings now seriously threats the environment safety. Reduction and recycling of red mud is now an urgent work in aluminum industry. High gradient superconducting magnetic separation (HGSMS) system was applied to separate the extreme fine RM particles (<100 #mu#m) into high iron content part and low iron content part. Two sorts of RM were fed in the HGSMS. The iron oxide contents in concentrates were about 65% and 45% when RM 1 and RM 2 were fed respectively. Meanwhile, the residues contained 52.0% or 14.1% iron oxide in ...
In order to facilitate observations of low energy nuclear reactions, a new type recoil mass-separator together with a new gas-jet target system is being developed at the tandem accelerator facility in Kyushu University. The expected mass-resolving power of the separator is 220 for a solid angle of 10 msr and the practical thickness of the gas-jet target will exceed 0.1 atm#centre dot#cm for the light elements of H and He. (author).
A continuous-flow filter/concentrator for separating and/or concentrating particles in a fluid is disclosed. The filter is a three-port device an inlet port, an filter port and a concentrate port. The filter separates particles into two streams by the ratio of their dielectrophoretic mobility to their electrokinetic, advective, or diffusive mobility if the dominant transport mechanism is electrokinesis, advection, or diffusion, respectively.Also disclosed is a device for separating and/or concentrating particles by dielectrophoretic trapping of the particles.
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 ...
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 ...
Flow Tex and ABB Energiekabel GmbH have developed a technique which allows the recovery of cables without requiring any trenching works. The new technique was successfully used for the first time for a pilot project in 1995. The authors report on two recent recovery projects (1998) in which an optimised technology was used for recovering a total of 1 500 m system length of 110 kV low-pressure oil-filled cables in Stuttgart and Munich on very different conditions. The authors describe the operational experiences with the cable connections and highlight the background stipulating the removal of the cables. (orig.) [Deutsch] Ein Verfahren zur grabungsfreien Bergung von Kabeln, gemeinsam entwickelt von FlowTex und ABB Energiekabel, wurde erstmals in einem Pilotprojekt 1995 mit Erfolg eingesetzt. Die Verfasser berichten ueber zwei Bergungsprojekte, bei denen 1998 mit der optimierten Technik in Stuttgart und Muenchen insgesamt 1 500 Systemmeter ...
The paper examines the influence of various total strain amplitudes and mean strains on the cyclic deformation processes in GGG-60 at temperatures of 20 C, 350 C, and 500 C ,the total strain amplitudes being varied between 1.0 permille {<=}{epsilon}{sub a,t}{<=}3.8 permille , and the mean strains between -4.0 permille {<=}{epsilon}{sub m,t}{<=}4.0 permille . - [Deutsch] In der Arbeit wird der Einfluss unterschiedlicher Totaldehnungsamplituden und Mitteldehnungen auf das Wechselverformungsverhalten von GGG-60 bei Temperaturen von 20 C, 350 C und 500 C untersucht. Dabei werden die Totaldehnungsamplituden zwischen 1,0 permille {<=} {epsilon}{sub a,t} {<=} 3,8 permille und die Mitteldehnungen zwischen -4,0 permille {<=} {epsilon}{sub m,t} {<=} 4,0 permille variiert. (orig./MM)
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 ...
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 ...
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 ...
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 bei serienmaessigen ...
This patent describes the producing of a refractory metal wherein a sponge refractory metal is produced as an intermediate product by the use of magnesium with the incidental production of magnesium chloride, and wherein residual magnesium is separated from the magnesium chloride and from refractory metal to a vacuum distillation step which fractionally distills the magnesium, the magnesium chloride, and the metal sub-chlorides; the steps of: recovering fractionally distilled vapors of magnesium chloride and metal sub-chlorides from a sponge refractory metal; separately condensing the vapors as separately recovered; and recycling the separately recovered magnesium at a purity of at least about 96%.
A study was made on extraction of a series of lithium and calcium salts by monopodands L with common formula R-C_6H_4-O-(CH_2CH_2O)_n-C_6H_4-R, where R - CH_2P(O)Ph_2, n 1-3. Extraction-chromatographic separation of lithium and calcium isotopes in systems of metal aquacomplex-solvatocomplex with L in organic phase was conducted. It was established that separation coefficients of "6Li/"7Li isotopes ranged between 1.003 #+-#0.001 and 1.017 #+-#0.002 at the maximal separation degree equal to 1.60. Separation of "4"0Ca/"4"4Ca isotopes was not fixed. 12 refs., 4 figs., 1 tab.
The law of the 30 December 1991 on the high activity long lived radioactive wastes reached the end. This synthesis final document presents the scientific and technological results, obtained still the end of 2005, on the separation and the transmutation of long lived radionuclides of high activity long lived radioactive wastes. It is organized in five chapters: a presentation of the context and the historical aspects, the researches, the objectives and the strategy of the axis 1, the researches results on the advanced separation, the researches results on the transmutation, the scenario of separation-transmutation and their environmental, technical and economical impacts. (A.L.B.)
In this work, chromatographic separation of niacin and niacinamide using pure water as the sole component in the mobile phase has been investigated. The separation and analysis of niacinamide have been optimized using three columns at different temperatures and various flow rates. Our results clearly demonstrate that separation and analysis of niacinamide from skincare products can be achieved using pure water as the eluent at 60^oC on a Waters XTerra MS C18 column, a Waters XBridge C18 column, or at 80^oC on a Hamilton PRP-1 column. The separation efficiency, quantification quality, and analysis time of this new method are at least comparable with those of the traditional HPLC methods. Compared with traditional HPLC, the major advantage of this newly developed green chromatography techniq...
The presence of an extraneous light gas must be taken into account in consideration of centrifugal separation of uranium isotopes, when there is inevitable leakage of such a gas through the gas sealant and/or leaking in from the atmosphere. Consideration is first given to the influence of the presence of the light gas on the maximum separative power. Then the basic equation for isotope separation containing a light gas is derived from Hirschfelder's diffusion equations. This equation is solved and the separative performance is expressed in terms of the shape factor and reflux parameter. The formulas for expressing the flow configurations of the gases are obtained for a simple model in which inflow and outflow prevail throughout the centrifuge. The corresponding equation for a model in which the gases flow in two concentric thin streams is also derived. It is concluded that the influence provided by the ...
Particulate Reinforced Titanium matrix composites (PRTi) exhibit some improved specific mechanical properties in comparison with those of unreinforced titanium alloys as a result of the combination of the high strength and stiffness of ceramic particles with the toughness and damage tolerance provided by the metal matrix. The poor tribological properties of the titanium exclude titanium alloys from applications where wear resistance is required (brakes, rotating parts, sliding parts). The addition of ceramic particles improves the tribological properties of metals sensitive to adhesive and /or abrasive wear significantly. In this work, the wear resistance and the friction coefficient of Ti6Al-6V-2Sn reinforced with TiC particles and Ti6Al-4V reinforced with SiC particles (prototype material) are compared with the unreinforced alloys. Pin on disc and pin on ring tests were carried out against standard steel (100Cr6) as a function of pressure, speed and temperature. The results show ...
Shell Solar GmbH is working on a variant of the so-called stacked elemental layer process for CIGSSe absorber production. The metal films resp. the selenium are deposited on the Mb electrode at room temperature by DC sputtering (CIG) or evaporation (Se) and then processed into semiconductors by rapid thermal annealing (RTP). Currently, the mean efficiency of the pilot plant is i 12.6 {+-} 0.2 % for non-sealed 30 x 30 cm{sup 2} modules, the key efficiency is 13.0 %. In addition to the 30 x 30 cm{sup 2} pilot line, a small series of 60x90cm2 modules was constructed in December 2004. Here, the mean efficiency was 13.0 percent while the average module power was higher than 60 W. The contribution also describes investigations of ceramically sputtered n-ZnO:Al layers with reduced Al concedntrations of 1 percent and on reactively sputtered n-ZnO.Al layers from the double roller magnetron. (orig.) [German] Bei Shell Solar GmbH wird eine Variante des sogenannten ...
Sprayforming offers the possibility to produce a variety of preforms in a single step directly from the melt. Numerous processing parameters ensure high flexibility but require detailed knowledge concerning the microstructure of sprayformed material depending on chemical composition and processing parameters. Within the current study fundamental investigations using unalloyed and low alloy steel grades (C15, C105, 100Cr6) for sprayforming of plates and billets have been performed concerning the influence of chromium and carbon content and selected processing parameters. Sprayformed preforms revealed austenite grain sizes up to 500 {mu}m depending on the development of porosity. Different types of porosity have been detected which can be associated with incomplete densification due to high cooling rates, solidification shrinkage and entrapped nitrogen. Atomisation gas pressure and carbon content are parameters of primary importance. (Abstract Copyright [2003], Wiley Periodicals, Inc.) ...
Aim: The purpose of this prospective study was to evaluate the value of immunoscintigraphy (ISG) with anti-225.28S in clinically suspected ocular melanoma. Methods: For this purpose standardized ISG was performed in 36 patients using both planar acquisition and emission computed tomography (ECT). Ocular melanoma was present in 31 patients. In 21 patients therapy was enucleation of the eye. These specimens were evaluated by histology and immunohistochemistry in 11 of 21 patients. Results: Regarding the clinical diagnosis, ISG was positive only in 15 of 31 patients with ocular melanoma, regarding histology in 11 of 21 and regarding immunohistochemistry in 5 of 6 patients with a positive immunoreaction. 5 patients showed no immunoreactivity, their ISG was negative. Conclusion: Thus a good correlation between ISG and immunohistochemistry was observed. However ISG using the cutaneous melanoma antibody 225.28S cannot be recommended for the diagnostic work-up of an ocular melanoma considering ...
The methods introduced for the field of cleaning waste water can be classified under various processes. Chemical oxidation is done with ozone, hydrogen peroxide and ultraviolet irradiation with subsequent biological decomposition. Another method is ultra-filtration with recovery of valuable materials or waste water ponds with algae biomass to decompose ammonium compounds, nitrates and phosphates. (EF) [Deutsch] Die auf dem Gebiet der Abwasserreinigung vorgestellten Methoden kann man in verschiedene Verfahren einordnen. Die chemische Oxidation erfolgt mit Ozon, Wasserstoff-Peroxid, UV Bestrahlung und anschliessenden biologischen Abbau. Eine andere Methode ist die Ultrafiltration mit Rueckgewinnung von Wertstoffen oder Abwasserteiche mit Algenbiomasse zum Abbau von Ammoniumverbindungen, Nitraten und Phosphaten. (EF)
Many power plants use treated surface water as boiler feedwater and have difficulties in keeping within the limits for organic substances in feedwater (TOC < 200 ppb) or acid conductivity in steam condensate (< 0.2 {mu}S/cm). The characteristics of surface water and the role of organic substances in boiler feedwater are explained and discussed. [German] Viele Kraftwerke bereiten fuer die Erzeugung von Kesselspeisewasser Oberflaechenwasser auf und haben Probleme, die Richtlinien fuer organische Stoffe im Speisewasser (TOC < 200 ppb) oder Saeure-Leitfaehigkeit in Dampfkondensaten (< 0,2 {mu}S/cm) einzuhalten. Die besonderen Eigenschaften von Oberflaechenwaessern und die Bedeutung organischer Stoffe in Kesselspeisewasser werden erlaeutert und diskutiert. (orig.)
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)
Zusammenfassung Hintergrund Endograftimplantationen im oder am Aortenbogen stellen besondere Herausforderungen an die Implantationstechnik und an die mechanischen Eigenschaften von Stentgrafts und ihren Einf?hrungssystemen, bedingt durch die Notwendigkeit, die Prothesen punktgenau abzusetzen und durch die mit der Biegung im Aortenbogen zunehmende Reibungswiderst?nde innerhalb der Einf?hrungssysteme. Die Endograftsysteme der 1. Generation (Talent?, Zenith TX 1?, TAG?) zeigten in dieser Lokalisation technisch bedingte Limitationen. Neue Prothesen Bei den seit 2004 und 2005 verf?gbaren neuen Stentgrafts (E-vita?, Zenith TX 2?, Valiant?, Relay?) sind diese Limitationen weitgehend ?berwunden. Durch technische Verbesserungen von Stentgrafts und Einf?hrungssystemen ist es nun m?glich, auch lange ...
In the first part of this contribution, the definition of reference values is given and the theoretical and practical problems in the application of this concept are discussed. In this connection, the present resources on instrumentation and the technical requirements for dose assessment are described. In the second part, some consequences are taken and proposals for further actions are made. (orig.) [German] Im ersten Teil des Aufsatzes werden Definitionen von Referenzwerten in der radiologischen Diagnostik untersucht und die theoretischen und praktischen Probleme der Umsetzung des gesamten Konzepts eroertert. In diesem Zusammenhang werden auch der gegenwaertige Geraetebestand und die technischen Voraussetzungen zur Dosisermittlung beschrieben. Im zweiten Teil werden daraus Schlussfolgerungen gezogen und Vorschlaege zum weiteren Vorgehen gemacht. (orig.)
In the first part of this contribution, the definition of reference values is given and the theoretical and practical problems in the application of this concept are discussed. In this connection, the present resources on instrumentation and the technical requirements for dose assessment are described. In the second part, some consequences are taken and proposals for further actions are made. (orig.) [German] Im ersten Teil des Aufsatzes werden die Definition von Referenzwerten in der radiologischen Diagnostik untersucht und die theoretischen und praktischen Probleme der Umsetzung des gesamten Konzepts eroertert. In diesem Zusammenhang werden auch der gegenwaertige Geraetebestand und die technischen Voraussetzungen zur Dosisermittlung beschrieben. Im zweiten Teil werden daraus Schlussfolgerungen gezogen und Vorschlaege zum weiteren Vorgehen gemacht. (orig.)
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 ...
Calcium sulfate dihydrate which is co-produced in the scrubbing of waste gases from bituminous coal power plants is employed in the underground road securing after recrystallization. Beta-sulfate semi hydrate is obtained from the dihydrate by recrystallisation and it is used as such or as a stiff mixture with additives as a stowing material. Particularly fly ash from coal combustion units, washery refuses and development rocks from coal mining or slags from the metallurgical industry can be used as additives. The compressive and the bending tensile strength of the stowing material can be adjusted by the water content in case beta sulfate semihydrate is used as such.
This is a process for producing calcium sulfate dihydrate during desulfurization of stack gases from power station boilers, where the stack gases are introduced into a washing tower and are treated with a washing water suspension containing lime in the washing tower, where oxygen in the form of air or of air enriched in oxygen is also blown into the washing tower, and where the washing water suspension drawn off from the washing tower is fed back to the washing tower at a temperature of 45 to 50/sup 0/C in the circuit and at least part of the flow goes via a thickener and where calcium sulfate dihydrate slurry is drawn off from the thickener.
Coordination chemistry on transition metal chalcogenides offer better conditions for multielectron charge transfer processes on solid/electrolyte interfaces. In this contribution, materials whose band energies are derived from d-states of the transition metal will be shown. Problems related to the reactivity, stability and photoactivity toward the generation and conversion of fuels will also be discussed. (orig.) [Deutsch] Die an halbleitenden Uebergangsmetall-Elektroden beobachtete Koordinationschemie bietet guenstige Voraussetzungen fuer den Mehrelektronen-Transfer an der Festkoerper/Elektrolyt Grenzflaeche. Beispielhaft werden in diesem Beitrag Elektrodenmaterialien vorgestellt, deren Energiebaender sich von d-Zustaenden der Uebergangsmetalle herleiten. Diskutiert werden Probleme der Reaktivitaet, der Stabilitaet und der Photoaktivitaet im Hinblick auf die Erzeugung und Umsetzung von Brennstoffen. (orig.)
The energy cost of compressors accounts for up to 90% of the total cost. Oil-free compressors could reduce the cost almost by half, i.e. annual savings of 112,500 DM would be achievable. [German] Ueber die Gesamtlaufzeit betrachtet, machen die Energiekosten bei Verdichtern bis zu 90% der Gesamtkosten aus. Deshalb muss bei der Auswahl von Kompressoren dem Energieverbrauch besondere Aufmerksamkeit geschenkt werden. Mit oelfreien Kolbenkompressoren liessen sich in einem speziellen Fall die Kosten fast halbieren, was jaehrlichen Einsparungen von 112 500 DM entspricht. (orig.)
The low-cycle fatigue behaviour of copper and a-brass CuZn30 was investigated in uniaxial and biaxial tests. Planar biaxial fatigue tests were carried out using cruciform samples with proportional stain paths with and without phase shift between the two axes. Microcharacterisation was performed by electron microscopy as well as by high-resolution X-ray line profile analysis. The biaxial cyclic stress-strain curves show good agreement with the uniaxial ones using the von Mises equivalent strain hypothesis. The dislocation densities and microhardness values of the biaxial case, however, show significantly lower values compared to the uniaxial case at equivalent von Mises stresses.
Zusammenfassung Die Festigkeitshypothesen und Flie?fl?chen aus den klassischen Kursen der Mechanik (die Normalspannungshypothese, die Modelle nach von Mises und Tresca) reichen oft nicht aus, das tats?chliche Verhalten von Bauteilen unter Belastung zu erfassen. Deshalb werden in der Literatur weitere Modelle mit einem oder mehreren Parametern vorgeschlagen. Diese Modelle beschr?nken allerdings die Geometrien der zul?ssigen Formen der Fl?chen im Spannungsraum. In dieser Arbeit wird ein auf die Zugspannung normiertes Druck-Torsion-Diagramm vorgestellt, in dem sich die Modelle inkompressiblen Materialverhaltens miteinander vergleichen lassen. Mit diesem Diagramm wird der Begriff der Symmetrie der Fl?che in der ?-Ebene verdeutlicht. Die konvexen Fl?chen inkompressiblen Materialverhaltens sind ...
Diagnostic systems make it possible to recognize incipient faults in good time and help to increase the availability of power stations. The thermal efficiency and the effective terminal output are didicated by a number of influences. Deviations from the expected status can be identified via continuous recording of the operating parameters and calculation of derived data. An improved efficiency and economical load distribution lead to considerable cost savings. (orig.) [Deutsch] Die Verarbeitung von Messwerten und Signalen ermoeglicht eine umfassende Beurteilung des Anlagenzustandes und die Erkennung sich anbahnender Veraenderungen. Stoerungen, Schaeden oder eine unwirtschaftliche Betriebsweise koennen fruehzeitig erkannt werden. Erhoehte Verfuegbarkeit, geringerer Brennstoffverbrauch und optimierte Lastaufteilung bringen Kostenvorteile. (orig.)
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 ...
The article describes the solar aircraft `Icare`` which was constucted in a joint project by engineers and scientists of Stuttgart university. The aircraft requires slightly more than one kW for staying up. The theoretical fundamentals are presented in the dissertation of Peer Frank, ``Aircraft design for minimum fuel consumption` (Institute of Aircraft Engineering, Stuttgart, 1992). (orig.) [Deutsch] Allein mit Sonnenkraft kann das Flugzeug `Icare` fliegen. Es entstand in Gemeinschaftsarbeit von Ingenieuren und Wissenschaftlern der Stuttgarter Universitaet. Das Solarflugzeug Icare benoetigt etwas ueber ein Kilowatt, um oben zu bleiben. In seiner Doktorarbeit `Die Auslegung von Flugzeugen mit geringstem Antriebsleistungsbedarf` (Institut fuer Flugzeugbau, Stuttgart, 1992) hat der Duesseldorfer Peer Frank die theoretischen Grundlagen dazu behandelt. (orig.)
This conference of Deutsche Wissenschaftliche Gesellschaft fuer Erdoel, Erdgas und Kohle focused on energetic utilisation and recycling of waste materials and biomass, i.e. combustion, gasification and pyrolysis. Aspects of process control were gone into as well. [German] Die Fachbereichstagung der Deutschen Wissenschaftlichen Gesellschaft fuer Erdoel, Erdgas und Kohle beschaeftigte sich mit der energetischen und stofflichen Nutzung von Abfall und Biomasse. Verbrennung, Vergasung und Pyrolyse verschiedener Abfallstoffe sowie die Prozesssteuerung wurden eroertert.
The research project aimed at the selection or development of wear-reducing measures for submerged components of hydroelectric power plants. This comprised the optimisation of hydraulic profiles as well as materials testing for abrasion and cavitation. Another field of research was the development of appropriate application processes. (orig.) [German] Das Hauptziel des Forschungsvorhabens bestand in der Auswahl bzw. Entwicklung geeigneter Schutzmassnahmen zur Verschleissminderung an wasserberuehrten Komponenten von Wasserkraftanlagen. Diesem Ziel untergeordnet waren neben der Optimierung hydraulischer Profile auch Materialuntersuchungen hinsichtlich Verschleissbestaendigkeit gegenueber Abrasion und Kavitation. Ebenso war die Entwicklung geeigneter Applikationsprozesse ein wichtiger Bestandteil der Aufgabenstellung. (orig.)
All patients with von Willebrand?s disease (vWD) who showed an arterial or venous thrombosis and were reported in the literature have been evaluated. 11 patients had arterial thrombosis while 19 had venous thrombosis for a total of 30 cases. 9 out the 11 cases with arterial thrombosis had myocardial infarction. Two had cerebral thrombosis. Associated risk factors for arterial thrombosis were available only for three patients who showed, respectively, smoking and dyslipidemia (2 cases) and smoking and intravenous desmopressin infusion (1 case). The majority of patients with venous thrombosis showed DVT with or without PE. Four patients presented with apparently isolated PE. In two instances thrombosis occurred in unusual sites (central retinal vein and portal vein, respectively). Several as...
Knowledge, assessment and understanding of phenomena caused by ageing, together with systematic utilization and extension of the technical life-time of components and systems, are of critical importance to the safety and economy of electricity generation in nuclear power stations. Economic use can be optimized by integrated ageing and life-time management; it can also be used to improve performance characteristics. (orig.) [Deutsch] Fuer die Sicherheit und Wirtschaftlichkeit der Stromerzeugung in Kernkraftwerken sind die Kenntnis, Bewertung und Beherrschung alterungsbedingter Phaenomene und systematische Ausnutzung bzw. Verlaengerung der technischen Lebensdauer der Komponenten und Systeme von zentraler Bedeutung. Durch ganzheitliches Alterungs- und Lebensdauermanagement, das auch auf die Verbesserung von Leistungsmerkmalen abzielt, kann der wirtschaftliche Nutzen optimiert werden. (orig.)
Known trace-matrix-separation and enrichment procedures for the refractory metals Mo and W use very time-consuming batch-techniques. This paper presents the application of a quasicontinuous liquid chromatographic (LC) technique as a step towards automated ultratrace separation. The anionic peroxo complexes from Mo(VI) and W(VI) are used for the trace-matrix-separation. Optimization of the peroxide concentration permits a complete removal of all cationic analyte traces on the HPLC-suitable cation exchanger Nucleosil SA. The high chromato-graphic efficiency also allows a direct ion chromatographic separation of the removed traces. This leads to conclusions about the contribution of the analyte traces on the trace-matrix-separation column and the limits of determination. (author). 13 refs.; 12 figs.; 5 tabs.
Recently we have found that carbon nano-materials have ability to recognize softer actinides(III). In this presentation, separation of americium(III) from lanthanides(III) by chromatography with carbon nano-materials, such as carbon nano-tubes and graphite, has been investigated by batch adsorption experiments and chromatography. The separation factor (SF) between americium(III) and lanthanide(III) was about 2 in the range of pH from 1 to 4 by using carbon nano-tube, graphite and activated charcoal. The separation factor depended on the diameter of carbon nano-tubes. Smaller one, 3-20 nm diameter, showed the best selectivity for americium(III), which separation factor was about 2.0, although larger one, 40-70 nm, showed almost no selectivity. The same behavior has been observed by using graphite powder and activated charcoal although acid- or alkali pretreated activated charcoal which generally has ...
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 ...
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 ...
This article describes the utilization of plastic wastes in a blast furnace. The plastic waste is a substitution for petroleum and coal as a raw material for synthesis gas production. The synthesis gas is the reducing agent in the blast furnace for the reduction of iron ores. You can find here an ecological and economical analysis of this process in comparison to the utilization of petroleum and coal. (SR)
Based on the first part of this report the molybdenum loadings of the red mud were varied and the activity of the catalytic additives was tested in a batch autoclave with TJP VR. The 30% Molybdenum loading (sample Nr. 6) was found to be optimum. Further testing with two vacuum residues (TJP VR and ARH VR) and sample Nr. 6, indicates the influences of the process parameters for hydrogen pressures of 9-15 MPa, temperatures of 440-475 C and residence times of 0-60 min. Obviously 440 C, 12 MPa and a residence time of 30 min are best conditions for hydrocracking of both vacuum residues with sample Nr. 6. (orig.) [Deutsch] Beruhend auf dem ersten Teil des Berichtes wird der Belegungsgrad der Rotmasse mit Molybdaen variiert und die resultierenden katalytischen Zusaetze werden in einem Autoklaven mit TJR VR getestet. Ein Belegungsgrad mit 30% Molybdaen (Probe 6) scheint optimal zu sein. Mit diesem Zusatz werden die Einfluesse der Prozessparameter bei Wasserstoffkaltdruecken zwischen 9 und 15 ...
As waste disposal methods and long-term precautionary care of the environment are closely related, disposal of non-avoidable and intractable residual products is to be viewed primarily from a safety angle. Also, thermal processes airm mainly at treatment, not utilization. 'Safety' in this context addresses both the environmental compatibility of the products and the process itself. In other words, only mature techniques (i.e., safe, proven ones) are employed. (orig.)
In this work, the thermodynamic behaviour of single-stage horizontal spray coolers with one or more spray levels is experimentally examined. Further, a spray cooler calculation model was developed, in order to describe the processes and to make a comparison of the results of calculation and measurement. The state of the mine climate and the cold water are taken as the thermodynamic reference. (orig.).
By the year 2000, the Postal Service aims to reduce its diesel transport by around 15000 vehicles. The advisory service, Detecon, is reviewing alternatives for postal deliveries as part of the ''Post 2000'' initiative. One such system is an electric-powered vehicle with a zinc-air battery from the Israeli firm Electric Fluid Limited (EFL). (orig.)
Smart electricity and gas supply grids are a prerequiste for full-scale utilization of the potential of modern energy-saving appliances and equipment. Direct exchange of information between the supplier and the consumer is indispensable for reducing costly and energy-intensive peak loads. (orig.)
Summary.? Measuring von Willebrand factor (VWF) activity is essential to the diagnosis of von Willebrand disease (VWD). The VWF activity is usually assessed based on measurement of the ristocetin cofactor (VWF:RCo). However, that test is technically challenging and has high intra- and inter-assay variabilities. The HemosIL VWF activity (VWF:AC) is a fully automated assay, recently proposed as a good alternative to VWF:RCo for VWD diagnosis. This study was undertaken to assess this new method. First, the analytical performance of VWF:AC on an automated coagulo-meter (ACLTop) was determined, and then this new method was compared with VWF:RCo and the platelet function analyzer (PFA100) for 160 patients referred for VWD screening. The VWF:AC achieved acceptable precision with within-run and between-run coefficients of variation ranging from 2.3% to 14.1%, and linearity from 10% to 100%. Despite some marked differences between VWF:AC and VWF:RCo for ...
It may be necessary to reduce microbiological contamination of crude drugs (medicinal plants or their parts like roots, leaves, flowers). This can be done by treating the drugs with ionizing radiation. Meethods for detection of such an irradiation were developed. It could be pointed out that measurements of luminescence, viscosity and electron spin resonance were suitable for specific drugs, but not for all drugs. (orig.).
The regenerator of Stirling cycle machines has an relatively unknown potential for thermal shorting, because the thermal flow path within the solid of a randomly stacked wire mesh, which is defined by its 'connectivity', is unknown. Earlier publications have shown two principles of experimental techniques to quantify connectivity. One quantifies connectivity as a function of axial pressure using the electric current analogy, the other measures connectivity via the temperature gradients along a regenerator and a series-connected reference body of known conductivity. Both papers offer preliminary results of reduced usefulness related to the testing method or setup. This contribution describes a new setup and its technique, which results from the practical knowledge and experience of the first two attempts, and aims for an improved determination of connectivity of the original representative Stirling regenerators with and without housing. Please contact the author for ...
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 ...
A new procedure for an efficient and sparing cleaning procedure of turbines was developed. The procedure uses cleaning and passivation chemicals that solve effectively and homogeneously salt and ferrous oxide coatings from turbines, avoiding attacks from corrosion, plugging and unbalances. In several high-pressure and condensation turbines the cleaning procedure has been already put into practice. (orig.)
Biological cells of the nitrogen fixating bacteria Xanthobacter autotrophicus GZ 29 have been cultivated with 57-Fe, and from the nitrogenase of these cells the 57-Fe marked molybdenum-iron-protein is extracted. The Moessbauer spectra of this enzyme show that the structure of the iron cluster is similar to the structure in the molybdenum-iron-proteins of Azotobacter vinelandii, Klebsiella pneumoniae or Clostridium pasteurianum.
In this paper, we derive the moderate deviation principle for stationary sequences of bounded random variables with values in a Hilbert space. The conditions obtained are expressed in terms of martingale-type conditions. The main tools are martingale approximations and a new Hoeffding inequality for non adpated sequences of Hilbert-valued random variables. Applications to Cramer-Von Mises statistics, functions of linear processes and stable Markov chains are given.
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 ...
It is necessary to measure strength and creep behavior to guarantee the safe and reliable usage of refractory alloys at extremely high temperatures. In the literature there is very little information available about the properties of Mo-Re alloys at temperatures higher than 1000 C. A special test facility has been designed and built for stress-rupture testing at very high temperatures (up to 3000 C) of refractory metals and alloys in inert atmospheres. - The stress-rupture strength as well as the creep behavior of molybdenum-rhenium alloys with rhenium contents between 41 and 51 wt.% have been determined at temperatures ranging from 1200 to 2000 C, and rupture times of up to 10 hours using this facility. Previous measurements of stress-rupture strength and creep behavior of pure rhenium have been compared with the measurement results of Mo-Re alloys. - The discussion of the values measured is based on metallographic test results and scanning electron microscopy (SEM) images of Mo-Re ...
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 ...
The article deals with the problem of a humidity addition to thermal conductivity, diffusion and latent heat effects in heat transfer through building components. It shows with examples humidity effects for exterior walls with core insulation, with composite insulation system as well as for insulated roof membrane assemblies. From these it can be summarized that - sorption humidity is for today`s construction conditions (good thermal insulation and humidity protection) a suitable reference quantity for the determination of practice-oriented, substance-specific and physically correct humidity additions to the thermal conductivity of hygroscopic components; - diffusion and latent heat effects are in case of good rain imperviousness and low water absorbing capacity of the exterior component layers of secondary importance for transmission heat losses; - an increase in insulating layer thickness in order to improve the thermal insulation is possible without humidity problems; - today`s ...
The system study 'High Temperature Superconductivity (HTS) in power systems' lists the technical and economical advantages for power generation, transmission and distribution systems using components made of HTS material as seen in the light of current knowledge in the superconductivity area. This report lists the advantages of using high-temperature superconductivity in the power industry area and summarises the results obtained in various case studies on the subject.
Due to the fast cooling of steam turbines, the shutdown time during maintenance or when repairing faults and damage can be shortened. This booklet describes various processes for cooling steam turbines. It is recommended that fast cooling should be planned in designing new plants and corresponding arrangements should be provided in the form of pipe connections and valves. (DG).
Experts tend to disagree about the economic effects of air pollution abatement measures. This book, which addresses also non-experts, explains the analytical background on the basis of available data. The authors conclude that there is a wide range of political options for achieving the goal of air pollution abatement. They differentiate between the various levels of discussion and show how misinterpretations of scientific results come about, thus making an important contribution to a discussion that is based on facts rather than emotions. [German] Die Einschaetzungen zur wirtschaftlichen Bewertung von Klimaschutzmassnahmen, insbesondere zur Steigerung der Energieeffizienz, sind sehr widerspruechlich. Dieses Buch erlaeutert anhand von Zahlenmaterial die analytischen Hintergruende und ist auch fuer Nicht-Oekonomen verstaendlich geschrieben. Die Autoren kommen zu dem Schluss, dass in vielen Bereichen rentable Energiesparpotentiale nicht erkannt ...
The vibration behavior of turbomachine bladings is described, and the behavior of different kinds of coupled low pressure stages was experimentally investigated. Besides purely stationary flow conditions, conditions were also considered where pulsating fl...
Nondestructive inspection of carbon fibre-reinforced plastics (CRFP) using eddy current methods is based not only on the conductivity of the fibres. High frequencies (up to 10 MHz) give access to capacitive effects reflecting properties of the matrix. The paper presents a method using rotating eddy current probes to measure the anisotropic electrical properties. Potential applications of this method are the structural identification of laminates and the estimating of its degradation. (orig.)
The report investigates a number of joining techniques, i.e. isothermal solidification, ultrasonic welding, thermocompression, and glueing. (HW) [Deutsch] In diesem Vorhaben wurden verschiedene Verbindungstechniken untersucht: Isotherme Erstarrung; Ultraschall-Schweissen; Thermokompression; Leitkleben. (HW)
This compact book of tables attempts to give practicians a survey of the corrosion behaviour of common structural and coating materials. Corrosion resistances are presented for steels, alloys, plastics, elastomers, graphite, glasses, and stoneware in environments of NaOH, HNO{sub 3}, SO{sub 2}, ZnCl{sub 2}, NH{sub 3}, H{sub 2}O{sub 2}, ethyl chloride, sodium acetate, and many others. (MM).
The catalytic properties of molybdena-alumina catalysts reduced in hydrogen were studied in the function of the reduction temperature, i.e. in the function of the extent of reduction. The deuterium exchange reaction of benzene was used as model catalytic reaction. It was concluded that the reaction rate constant and the multiplicity factor decreased with the extent of reduction parallel with the change in the extent of dehydroxylation of the catalysts. (orig.)
Old banknotes may be tomorrow's biomass. Experts on biowaste are investigating two new processes for disposal of the 1000 tonnes of old bills sorted out every year which may be an alternative to combustion. The author presents details.
This bibliographical study compiles and analyzes findings about the metabolism and resorption of molybdenum. Besides including studies on the physiology of molybdenum 99, a general survey is given on molybdenum in the environment and on its physiological behaviour. In particular, information on the dependence of molybdenum resorption on various factors, such as the chemical form, antagonisms etc., are gathered from literature. These factors have to be considered for sensibly carrying out necessary experiments.
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 ...
For millions of people general noise and especially traffic noise are the main sources of environmental pollution. The increasingly stricter noise pollution abatement limiting values laid down by the law call for motor vehicle noise pollution abatement measures. Within the framework of today`s cost- and performance-oriented automobile and engine development developing engineers are required to reduce noise levels. The present state of the art is described and future possibilities of combustion engine structure-borne noise calculation and optimization are discussed from the point of view of K + P Computerunterstuetzte Strukturanalysen GmbH. (orig.) [Deutsch] Laerm allgemein und dabei speziell wiederum der Verkehrslaerm steht fuer Millionen von Menschen an allererster Stelle der persoenlichen Belastung durch die Umwelt. Zur Minderung der Laermbelastung werden vom Gesetzgeber immer schaerfere Grenzwerte vorgeschrieben, die dazu zwingen, Massnahmen zur ...
The acceptances to be obtained during the first operational run, refer to measures proving the functional integrity of the turbine control system and assuring the compliance with the maximum allowable overspeed in case of lead changes or perturbations. The Guideline concerns essentially speed, power, and pressure controllers coupled to generators. It may be appropriately extended to steam turbines serving other purposes.
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 ...
A radiochemical charged particle activation procedure for production and separation of carrier free {sup 52,56}Mn, {sup 55,56,58}Co and {sup 56,57}Ni has been developed. The radioisotopes produced on bombardment of an iron foil target with a 40 MeV {alpha}-particle beam through the nuclear reactions, Fe({alpha}, {alpha}pxn){sup 52,56}Mn, Fe({alpha}, pxn){sup 55,56,58}Co and Fe({alpha}, nx){sup 56,57}Ni, have been separated by LLX. The target element and the activation products have been sequentially separated from an HCl medium using diethylether and the liquid anion exchanger, TIOA, as extractants. Extent of separation and purity of the carrier free radiotracers at different stages of their LLX separation have been verified by taking recourse to {gamma}-ray spectrometry. (Author).
Burnable poisons are used in nuclear reactors to produce a more level distribution of power in the reactor core and to reduce to necessity for a large control system. An ideal burnable poison would burn at the same rate as the fuel. In this study, separation of neutron-absorbing isotopes was investigated in order to eliminate isotopes that remain as absorbers at the end of fuel life, thus reducing useful fuel life. The isotopes Gd-157, Dy-164, and Er-167 were found to have desirable properties. These isotopes were separated from naturally occurring elements by means of plasma separation to evaluate feasibility and cost. It was found that pure Gd-157 could save approximately $6 million at the end of four years. However, the cost of separation, using the existing facility, made separation cost- ineffective. Using a magnet with three times the field strength is expected to reduce the ...
Anaerobic digestion of slurry represents an environmental opportunity for both slurry management and renewable energy production in countries with high animal density. This study evaluated the environmental impacts of 4 biogas production alternatives in which slurry was the only input in the process, without supplementary addition of easily degradable carbon. This was achieved by exposing the slurry to different separation technologies. The biomass mixture input for biogas production included solid fraction from slurry separation as well as raw slurry, proportioned in order to achieve economical methane yield. The separation processes considered in this study were mechanical separation; mechanical separation combined with the addition of flocculants; and mechanical separation combined with a thermal treatment. Four biogas alternatives were compared to a ...
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], ...
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 ...
The first commercial vehicle, built by Gottlieb Daimler in Cannstatt (Germany), head foto, had been the begin of a new transport technology around the world. Benz had been consolidated 1926 with Daimler to the Daimler-Benz AG with a new vehicle programme; all trucks over 5 t payload would be powered since 1935 by diesel engines only. Worldwide all-wheel drived vehicles had been under development for different purposes. After 1945 the European Automobil industry launched at first former types followed by new designed and improved types. The eight-wheeler used since the twentees in England conquered Switzerland, and in 1984 Germany too. The development of gear boxes and drive axles had been influenced on the drive train demands depending of the engine output and speed and the increased GTW. The future of the commercial vehicles will be determined by the European legislation, higher economy and reduced-pollutant Euro II and later Euro III engines, further by the cooperation of the truck ...
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 ...
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 ...
The chemical separation of carrier-free "2"0"3Pb following deuterium bombardment of a "2"0"3Tl target is described. Coprecipitation from strontium sulphate was used to separate the "2"0"3Pb from a solution of the thallium target in sulphuric acid. The SrSO_4 precipitate was filtered, washed and dissolved in hydrochloric acid, from which "2"0"3Pb was again separated by precipitation on sodium chloride from a strongly acid solution. Advantages of the system are discussed and optimum conditions given. (U.K.).
Separations of metal ions on the basis of Donnan dialysis across anion-exchange membranes should be possible if the receiver electrolyte composition favors the formation of selected anionic complexes of the sample metal ions. Moreover, such a separation has the possibility of being better suited from some applications than batch or column experiments with anion-exchange resins. The above hypothesis are tested on the platinum-group metal ions, Pt(IV), Rh(III), Pd(II), Ir(III), and Ir(IV). 13 references, 4 tables.
Separation of lithium isotope by NTOE compound was carried out with 0.01M HCl solution. The ion exchange capacity of NTOE was 0.8 meq/g. The separation factor, #alpha#=("7Li/"6Li)_s_o_l_i_d/("7Li/"6Li)_l_i_q_u_i_d was 1.0242 by the elution chromatography. The lighter isotope, "6Li was concentrated in the liquid phase, while the heavior isotope, "7Li was enriched in the solid phase. (author).
This paper describes the problems and capabilities of highly enriched actinide isotopes production by electromagnetic separation in the S-2 mass separator of VNIIEF. Isotope enrichment characteristics for uranium, plutonium, americium and curium isotopes, used in different nuclear physics experiments, and isotope contamination for single and double separations are presented. The capabilities for highly enriched "2"4"4Pu and "2"4"8Cm production for nuclear accelerator experiments and other applications are described, some details of the current and future programmes are given and the transport packaging is described. (orig.).
The chemical separation of carrier-free /sup 203/Pb following deuterium bombardment of a /sup 203/Tl target is described. Coprecipitation from strontium sulphate was used to separate the /sup 203/Pb from a solution of the thallium target in sulphuric acid. The SrSO/sub 4/ precipitate was filtered, washed and dissolved in hydrochloric acid, from which /sup 203/Pb was again separated by precipitation on sodium chloride from a strongly acid solution. Advantages of the system are discussed and optimum conditions given.
A heat storage compostion comprises sodium sulfate decahydrate as main component, a supercooling inhibitor, and a solid-liquid separation inhibitor. The composition is characterized in that hydraulic calcium sulfate and/or calcium sulfate dihydrate is contained as the solid-liquid separation inhibitor in an amount of 2-15 wt% base on the whole weight of the composition, whereby the solid-liquid separation, i.e. the sedimentation of the anhydrous sodium sulfate during the phase transition, is effectively prevented and the long-term stability is improved. The long-term stabilty of the composition can be more improved by addition of a silcia series of thickener.
Engine flow simulation was provided by four separately mounted air ejectors connected to a high-pressure air supply. The engine nacelle center lines were ...
... tests, one often encounters, for instance, separated flows with large ... It is suspected that the flow-quality criteria given in AGARD Report No. ...
If you are a FERS employee (the current retirement system), you lose your sick leave if you do not return to Federal service. If you separate from the Federal ...
BackgroundVisual acuity, the ability of the visual system to distinguish two separate objects at a given angular distance, is influenced by the optical and neuronal properties of...Full Text Available
An investigation into a three-dimensional, curved shock wave interacting with a three-dimensional, curved boundary layer on a slender body is presented. Three different nose profiles mounted on a cylindrical body were tested in a supersonic wind tunnel and numerically simulated by solving the Navier?Stokes equations. The conical and hemispherical nose profiles tested were found to generate shock waves of sufficient strength to separate the boundary layer on the cylinder, while the shock wave generated by the ogival profile did not separate the boundary layer. For the separated flow, separation was found to occur predominantly on the windward side of the cylinder with the lee-side remaining shielded from the direct impact of the incident shock wave. A thickening of the boundary layer on the...
Gas separation membranes with polydimethylsiloxane(PDMS)/polystyrene(PS) were prepared by using the sequential interpenetrating polymer network (IPN) method with various PS contents (10?70wt%). These gas separation membranes can be applied to reduce the smoke density in the emission gas of diesel engines. PS content has a pronounced effect on the membrane performance. It was found that the optimized PS contents in the final membrane were 50wt%. The emission capacities of diesel engines used in this study were 632 cc and 11,149 cc. When the oxygen separation membrane was used in the diesel engines, the smoke density of both diesel engines was remarkably reduced (35?73%). The oxygen concentration in the inlet air affects the composition of the emission gases. Especially, hydrocarbon (HC) dec...
flow and changing scheulingparameters during real-time ..... illustrative purposes, only two minimum separation ..... Individual Flights and Air Traffic, AGARD. No. ...
... 14(a)), a short laminar separation bubble is evident on the ... Natural Laminar Flow and Laminar Flow Control, RW Barnwell and MY ... AGARD CP No. ...
... changes in the wing shock/ separation patterns throughout ... to Reynolds number and tunnel flow quality before ... AGARD Conference Proceedings No ...
Studies on the separation of Ag(I) during the recovery of Pu from analytical waste generated during potentiometric determination of Pu using AgO as oxidant, by precipitation of Pu as ammonium plutonium (III) oxalate have shown that most of the Ag(I) is separated during the reduction of Pu to Pu(III) state by ascorbic acid. A decontamination factor of 54 was obtained. Additional a decontamination factor of 5.8 was obtained during the precipitation of Pu as ammonium plutonium (III) oxalate. The Ag content was determined by gamma spectrometry, using "1"1"1Ag as a tracer (T_1_/_2 7.45 d, #gamma# 342.1 keV) and HPGe as detector. The studies indicate that Ag is preferentially separated almost quantitatively during the recovery of plutonium, when acidity adjustment is done with NaOH instead of NH_3. (author)
The tegument of tapeworms is known to be composed of an outer syncytial cytoplasm layer which includes microtriches and cytoplasmic organelles (= syncytial layer), and a parenchymatous cytoplasm layer...Full Text Available
A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity RbCl product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant RbCl is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.
A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity RbCl product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant RbCl is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.
A rapid and highly reproducible chromatographic technique has been developed for analysis and purification of complex mixtures of oligoribonucleotides. The method utilizes a column of microparticulate...Full Text Available
A simple method is presented for the separation of lead-203 from copper-backed thallium cyclotron targets. The procedure involves cation-exchange chromatography in hydrochloric acid and hydrochloric acid-acetone mixtures. Further purification involves anion-exchange chromatography in nitric acid-hydrobromic acid mixtures. A cation-exchange column containing 3.0 g of resin can handle as much as 15 g of thallium and 160 mg of copper. An anion-exchange column containing 3.0 g of resin can separate lead from up to 200 mg of thallium and 10 mg of copper. Separations are extremely sharp and less than 0.1 ..mu..g of thallium and less than 0.1 ..mu..g of copper remain in the lead-203 fraction.
A simple method is presented for the separation of lead-203 from copper-backed thallium cyclotron targets. The procedure involves cation-exchange chromatography in hydrochloric acid and hydrochloric acid-acetone mixtures. Further purification involves anion-exchange chromatography in nitric acid-hydrobromic acid mixtures. A cation-exchange column containing 3.0 g of resin can handle as much as 15 g of thallium and 160 mg of copper. An anion-exchange column containing 3.0 g of resin can separate lead from up to 200 mg of thallium and 10 mg of copper. Separations are extremely sharp and less than 0.1 #mu#g of thallium and less than 0.1 #mu#g of copper remain in the lead-203 fraction. (author).
Bismuth radioisotopes, produced by 50-MeV proton bombardment of a lead target in a cyclotron, are separated from the lead target material by ion-exchange chromatography on a column containing 5.0 ml of Chelex 100. After a decay period of 24 hr, the /sup 203/Pb formed in situ is eluted from the column and then separated from /sup 200/Tl and /sup 201/Tl on a second ion-exchange column containing 0.5 ml of Chelex 100. Separations are sharp and carrier-free /sup 203/Pb is obtained.
A specific radiochemical procedure for indium determination in semiconductor-grade silicon, using an inorganic ion exchanger (cerium oxalate) is proposed.
This is the monthly progress report for the Savannah River Technology Center, which covers the following areas of interest, Tritium, Separation processes, Environmental Issues, and Waste Management.
This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation; tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)
This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation; tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)
The fundamental product of tetracycline hydrochlorine gamma radiolysis was separated in its solid state. From the results of spectroscopic studies it has been established that it is des-N,N-dimethylaminotetracycline.
This paper describes the construction of PWR horizontal steam generator in Soviet Union, the water chemistry treatment for secondary side, the design of steam separator, the test of heat transfer characteristics and operation. (author).
Several years ago, the AGARD Structures and Materials Panel selected ... flow separation appears to have occurred during the tests, and the angles of attack ...
... and regional land, sea, air, and space-based systems, and ... means of delivery of weapons where such ... a separable and divisible part of the weapon. ...
A complex modulated structure is described for reactive elements that have the capability of considerably more heat than organic explosives while generating a working fluid or gas. The explosive and method of fabricating same involves a plurality of very thin, stacked, multilayer structures, each composed of reactive components, such as aluminum, separated from a less reactive element, such as copper oxide, by a separator material, such as carbon. The separator material not only separates the reactive materials, but it reacts therewith when detonated to generate higher temperatures. The various layers of material, thickness of 10 to 10,000 angstroms, can be deposited by magnetron sputter deposition. The explosive detonates and combusts a high velocity generating a gas, such as CO, and high temperatures. 2 figs.
In order to get the separation of natural isotopes of lithium by electrolytic amalgamation, an electrolytic cell with a confined mercury cathode was used to obtain data for the design of a separation stage. The initial work was followed by the design of a moving mercury cathode electrolytic cell and three experiments with six batches stages were performed for the determination of the elementary separation factor. The value obtained, 1.053, was ill agreement: with the specialized literature. It was verified in all experiments that the lithium - 6 isotope concentrated in the amalgam phase and that the lithium - 7 isotope concentrated in the aqueous phase. A stainless-steel cathode for the decomposition of the lithium amalgam and the selective desamalgamation were also studied. In view of the results obtained, a five stages continuous scheme was proposed. (author)
... AGARD AR-319, Volume 2. Knight, D., Zhou ... a Turbulent Boundary Layer in a Supersonic Flow. ... of Development of Separated Flows in Compression ...
A LLX procedure for carrier-free separation of the radioisotopes, {sup 47}Sc, {sup 48}V and {sup 48},{sup 49},{sup 51}Cr, the 40 MeV {alpha}-particle activation products of titanium has been developed. Sequential separations of the radionuclides produced in the titanium matrix through the nuclear reactions ({alpha}, {alpha}p{chi}n), ({alpha}, p{chi}n) and {alpha}, ({chi}n) have been performed through LLX from aqueous H{sub 2}SO{sub 4} and HClO{sub 4} acid media using the liquid cation exchanger, HDEHP, as an extractant. Purity of the carrier-free radiotracers at different stages of their separations has been verified by {gamma}-ray spectrometry. (author).
Mechanisms, AGARD Conference Proceedings No. 131, 1974, Paper No. 11. ... Olsen, W. and Karchmer, A., Lip Noise Generated by Flow Separation From Nozzle ...
indicate incipient flow separation. The peak stagnation line ...... culations of Transonic Fan Performance, AGARD Propul- sion and Energetics Symposium on ...
flow separation occurred at the junction of the tip fin and the fuselage. ...... Systems, presented at the AGARD Guidance and Control and Flight Mechanics ...
the booms, separated by 12.5 m, deployed using the well proven MILSTAR hinge technology. ...... MILSTAR. Military Strategic and Tactical Relay satellite ...
rotor flow field in which the main rotor operates. The majority of ..... early separation predicted by their CFD code was ...... Airfoil, AGARD Fluid Dynamics Panel ...
Electrostatic beneficiation of dry coal has received significant attention in the last decade. In this process the coal is ground and then charged, either by corona charging or by triboelectrification (friction charging). Coal and minerals receive different levels of charge -- often opposite polarities in the case of triboelectrification -- and can then be separated based on differences in electrical mobility. Problems associated with the techniques include rapid deposition of particles on the electrodes, thus, effecting further separation. The goal of this project is to optimize the electrostatic coal cleaning process to remove pyrites and inorganic materials through studies of the electrostatic properties of powdered coal, in-situ measurements of the electrodynamics of coal and mineral particles inside the separator, and development of self-cleaning collector plates for continuous separation.
The symposium reviewed the use of electronics in mining today. Subjects covered include control systems; remote sensing; telemetry; data transmission; microprocessors and transportation systems. 15 papers have been abstracted separately.
In a recent paper [4], Duarte and Jutten investigated the Blind Source Separation (BSS) problem, for the nonlinear mixing model that they introduced in that paper. They proposed to solve this problem by using information-theoretic tools, more precisely by minimizing the mutual information (MI) of the outputs of the separating structure. When applying the MI approach to BSS problems, one usually determines the analytical expressions of the derivatives of the MI with respect to the parameters of the considered separating model. In the literature, these calculations were mainly reported for linear mixtures up to now. They are more complex for nonlinear mixtures, due to dependencies between the considered quantities. Moreover, the notations commonly employed by the BSS community in such calculations may become misleading when using them for nonlinear mixtures, due to the above-mentioned dependencies. We claim that the ...
Jan 31, 2002 ... Sequential Flow of EDA Functionality for Flow with Separation ...... for Automated Air Traffic Management," AGARD Lecture Series No. ...
be due to flow separation and reattachment, rather than transition. The analysis predicted a .... lations of Transonic Fan Performance," AGARD Propulsion ...
Interactions (FCCI) University of Wisconsin, Madison Thermal Properties of LiCl-KCl Molten Salt for Nuclear Waste Separation University of Wisconsin, Madison Next Generation...
... been demonstrated in steady compressible flows. ... steady Compressible Flow on an Oscillating Airfoil ... of Oscillating Airfoils", AGARD-CP-552, Aug. ...
It is shown numerically that on a time scale of order 1 msec a neutron star with pion condensation will undergo separation into a core and an envelope with a sharp interface. The envelope will not, however, be ejected.
... including those with rear separation, ... flows ibout airfoils." AIAA Paper 'Jo 97-0419, 1987). ... "Effects of streamline curvature on turbulent flow." AGARD ...
Cambridge scientists in the late 1980's. This same team, then headed by Professor John Baldwin, built the world's first separated-element optical/infrared aperture synthesis...
Hamed, A. and A. Mohamed, "Assessment of Shock Induced Flow Separation and ...... AGARD Symposium on Combined Cycle Propulsion for Hypersonic Application, ...
We construct the Baxter Q-operator and the representation of the Separated Variables (SoV) for the homogeneous open SL(2,R) spin chain. Applying the diagrammatical approach, we calculate Sklyanin's integration measure in the separated variables and obtain the solution to the spectral problem for the model in terms of the eigenvalues of the Q-operator. We show that the transition kernel to the SoV representation is factorized into the product of certain operators each depending on a single separated variable. As a consequence, it has a universal pyramid-like form that has been already observed for various quantum integrable models such as periodic Toda chain, closed SL(2,R) and SL(2,C) spin chains.
airborne separation assistance systems (ASAS) to ... operations should be limited to the outer traffic flow ...... AGARD Meeting on Machine Intelligence in Air ...
Two different approaches can be used in phylogenomics: combined or separate analysis. In the first approach, different datasets are combined in a concatenated supermatrix. In the second, datasets are...Full Text Available
... of the cycle shows that the separation area ea. ... with suitable flow solvers based on the Reynolds ... AGARD 75th Fluid Dynamics Panel Meeting and ...
mulation, with flow quantities stored at the grid vertices. OVERFLOW ..... attack: a separation bubble near the trailing edge of the ..... AGARD CP-429, Jul. 1988. ...
... of "position error" in the AGARD Multilingual Aeronautical ... when it cones into the aircraft flow field it ... on actual bank angle and separation, may be - ...
flow separation and vortices shed from the airplane forebody when flying at ...... AGARD Conference Proceedings 548: Technologies for Highly Maneuverable ...
This CD-ROM contains 34 contributions which were held on the 36th MPA seminar 2010 in Stuttgart (Germany). 32 contributions are separately analyzed for the ETDE database.
High gradient magnetic separation (HGMS) of magnetic materials from fluids or waste products has many established industrial applications. However, there is currently no technology employing HGMS for ex-vivo biomedical applications, such as for the removal of magnetic drug- or toxin-loaded spheres from the human blood stream. Importantly, human HGMS applications require special design modifications as, in contrast to conventional use where magnetic elements are permanently imbedded within the separation chambers, medical separators need to avoid direct contact between the magnetic materials and blood to reduce the risk of blood clotting and to facilitate convenient and safe treatment access for many individuals. We describe and investigate the performance of a magnetic separator prototype designed for biomedical applications. First, the capture efficiency of a prototype HGMS ...
Within its competence for energy research, the Bundesministerium fuer Wirtschaft und Arbeit (BMWA) (Federal Ministry of Economics and Technology) sponsors investigations into the safety of nuclear power plants. The objective of these investigations is to provide fundamental knowledge, procedures and methods to contribute to realistic safety assessments of nuclear installations, to the further development of safety technology and to make use of the potential of innovative safety-related approaches. The Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, by order to the BMWi, continuously issues information on the status of such investigations by publishing semi-annual and annual progress reports within the series of GRS-F-Fortschrittsberichte (GRS-F-Progress Reports). Each progress report represents a compilation of individual reports about the objectives, work performed, results achieved, next steps of the work etc. The individual reports are prepared in a standard form by the ...
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 ...
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 ...
In order to predict thermal hazards of high-energy materials, accurate kinetics constants must be determined. Predictions of thermal hazards for mixtures of high-energy materials require measurements on the mixtures, because interactions among components are common. A differential-scanning calorimeter (DSC) can be used to observe rate processes directly, and isothermal methods enable detection of mechanism changes. Rate-controlling processes will change as components of a mixture are depleted, and the correct depletion function must be identified for each specific stage of a complex process. A method for kinetics measurements on mixed explosives can be demonstrated with Composition B is an approximately 60/40 mixture of RDX and TNT, and is an important military explosive. Kinetics results indicate that the mator process is the decomposition of RDX in solution in TNT with a perturbation caused by interaction between the two components. It is concluded that a ...
Relative densities and relative massic heat capacities have been measured for aqueous solutions of Y(ClO_4)_3, Yb(ClO_4)_3, Dy(ClO_4)_3, and Sm(ClO_4)_3 at T=(288.15,298.15,313.15, and 328.15) K and p=0.1 MPa. These measurements were made in the concentration range 0.01624#<=#m/(mol#centre dot#kg"-"1)#<=#0.41822 using a Sodev 02D Vibrating Tube Densimeter and a Picker Microflow Calorimeter, respectively. To counter the potential effects of hydrolysis, aqueous solutions of the investigated salts were acidified with perchloric acid. After correcting for the presence of the acid, the measured properties were used to calculate apparent molar volumes and apparent molar heat capacities for solutions of the perchlorate salts in water. The calculated apparent molar properties were modeled at each investigated temperature using Pitzer ion interaction equations to produce estimates of apparent molar volumes and heat capacities at infinite dilution. In addition, the ...
Neutron capture cross sections of actinides are of great relevance for the Transmutation of Nuclear Waste in Accelerator Driven Systems (ADS) and Generation-IV reactors. The neutron capture cross sections of {sup 237}Np and {sup 240}Pu in the range of 1 eV to 2 keV were measured at the n-TOF facility with a Total Absorption Calorimeter. The data have been analyzed with the SAMMY code. The corresponding covariance matrices have been generated. The final cross sections are presented and compared to the previously existing ones.The n-TOF {sup 237}Np {sigma}(n,{gamma}) is in agreement with the evaluated data files below 300 eV and its is lower by 10 to 15% up to 2 keV. This discrepancy with the evaluated data files is also observed in the capture cross section derived from the transmission measurements of Gressier et al. In the case of the {sup 240}Pu {sigma}(n,{gamma}), the n-TOF {sigma}(n,{gamma}) agrees within uncertainties with JENDL-3.3 and JEFF-3.1, except for a ...
Isobaric specific heat capacities were measured for (2-methyl-2-butanol + heptane) mixtures and cyclopentanol within the temperature range from (284 to 353) K, and for 2-methyl-2-butanol in the (284 to 368) K temperature interval by means of a differential scanning calorimeter. The excess molar heat capacities were calculated from the experimental results. For the temperature range from (284 to 287) K, the excess molar heat capacity is S-shaped with negative values in the 2-methyl-2-butanol rich region and with small negative values at low alcohol concentrations at temperatures from (295 to 353) K. The excess molar heat capacities are positive for all compositions under test at temperatures from (288 to 294) K. The results are explained in terms of the influence of the molecular size and configuration of the alkanols on their self-association capability and of the change in molecular structure of the (2-methyl-2-butanol + heptane) mixtures. The differences between ...
This report covers the technical effort through February, 1989. This effort was directed towards the technology associated with the development of a large scale, long pulse DF-CO{sub 2} chemical laser. Optics damage studies performed under Task 1 assessed damage thresholds for diamond-turned salt windows. Task 2 is a multi-faceted task involving the use of PHOCL-50 for laser gain measurements, LTI experiments, and detector testing by LANL personnel. To support these latter tests, PHOCL-50 was upgraded with Boeing funding to incorporate a full aperture outcoupler that increased its energy output by over a factor of 3, to a full kilojoule. The PHOCL-50 carbon block calorimeter was also recalibrated and compared with the LANL Scientech meter. Cloud clearing studies under Task 3 initially concentrated on delivering a Boeing built Cloud Simulation Facility to LANL, and currently involves design of a Cold Cloud Simulation Facility. A Boeing IRAD funded theoretical study ...
Net heats of reaction were measured in an isothermal calorimeter for both single phase (organic) and two phase (organic and aqueous) TBP/HNO{sub 3} reacting solutions at temperatures above 100 C. The oxidation rate constant was determined to be 5.4E-4 min{sup {minus}1} at 110 C for an open ``vented`` system as compared to 1.33 E-3 min{sup {minus}1} in the closed system. The heat released per unit material oxidized was also reduced. The oxidation in both phases was found to be first order in nitric acid and pseudo-zero order in butylnitrate and water. The hydrolysis (esterification) rate constant determined by Nichols` (1.33E-3 min{sup {minus}1}) fit the experimental data from this work well. Forced evaporation of the volatile components by the product gases from oxidation resulted in a cooling mechanism which more than balanced the heat from the oxidation reaction in the two-phased systems. Rate expressions were derived and rate constants determined for both the ...
The aim of this work was to compare the electrochemical behaviors and safety performance of graphite and the lithium titanate spinel Li1.33Ti1.67O4 with half-cells versus Li metal. Their electrochemical properties in 1 M LiPF6/EC + DEC (1:1 w/w) or 1 M LiPF6/PC + DEC (1:1 w/w) at room and elevated temperatures (30 and 60 deg C) have been studied using galvanostatic cycling. At 30 deg C graphite has higher reversible capacity than Li1.33Ti1.67O4 when using the LiPF6/EC + DEC as electrolyte. At 60 deg C graphite declines in cell capacity yet Li1.33Ti1.67O4 remains almost unchanged. In a propylene carbonate (PC) containing electrolyte, graphite electrode exfoliates and loses its mechanical integrity while Li1.33Ti1.67O4 electrode is very stable. An accelerating rate calorimeter (ARC) and microcalorimeter have been used to compare the thermal stability of lithiated lithium titanate spinel and graphite. Results show that Li1.33Ti1.67O4 may be used as an alternative ...
The thermal behaviour of 21 proteinaceous l-amino acids either as pristine samples and also as radiolyzed (3.2 MGy) samples was studied with the differential scanning calorimeter. The onset and peak melting point as well as the melting enthalpy of all samples before and after the radiation treatment was measured and reported. The residual amount of each amino acid survived to the radiation dose of 3.2 MGy (N_#gamma#) was measured from the melting enthalpies before and after radiolysis and hence the radiation resistance of each amino acid has been determined. The radiolysis causes a systematic reduction of the melting enthalpy and a shift of the onset and peak melting point to lower values. It is shown that N_#gamma# does not correlate with the melting points of the amino acids but shows a correlation with the entity of the shift of the melting point peaks occurred after radiolysis. Such correlation instead does not exist between the N_#gamma# parameter and the ...
Photoinduced charge separation reactions form the basis for energy storage processes in both natural and artificial photosynthesis. Moreover, rapid reversible photoinduced electron transfer reactions are a class of photophysical phenomena that can be exploited to develop schemes for optical switching. Examples from each of these fields are discussed.
Electrophoresis in a sucrose gradient at pH values between 5 and 8 separated housefly DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane] dehydrochlorinase into two major fractions....Full Text Available
The electrochromatographic behavior of 25 metal ions on zirconium tungstate-impregnated papers is described. Six background electrolytes were used. On the basis of the differential mobilities of metal ions which depend on the ion-exchange properties of zirconium tungstate and the nature of complex formation with the electrolytes, some important binary and ternary separations have been achieved.
Using the example of perhydrophenanthrene, perhydroanthracene and cyclopentanodecalin isomers a possibility is shown to use packed capillary columns containing graphitized thermal carbon black for a complete separation of high-boiling mixtures of polycyclic saturated hydrocarbon isomers in accordance with the geometric structure of their molecules.
A method has been developed for the adsorption of Sc"I"I"I employing inorganic ion exchanger zirconium phosphosilicate by batch method. Effects of various parameters have been evaluated on the percentage adsorption of Sc"I"I"I. Separation of Sc"I"I"I from various other elements is standardized. (author)
Features of deep inelastic nuclear reactions proceeding on dense fluctuations of nuclear matter (fluctons) are briefly considered. Fluctons, which can be many-quark bags or drops of quark-gluon plasma, are studied. Their properties are discussed, viz., characteristic parameters of nuclear matter inside a flucton - temperature and density close to the critical values for a phase transition. These values can be reached or exceeded if the flucton-flucton collision events are separated. The separation method is discussed
This program is concerned with the development of an advanced method for the separation of hydrogen sulfides from coal gas. The process utilizes an electrochemical membrane which removes hydrogen sulfide without cooling the gas and with negligible pressure loss through the separator.
The fragment separator at GSI, Darmstadt, has been used to produce and separate very proton rich nuclei in the {sup 100}Sn region. By fragmentation of a {sup 112}Sn beam at 1 A{center_dot}GeV we produced nuclei along the rp-process path between {sup 77}Y and {sup 98}In. By implanting these ions into a silicon detector stack we were able to determine their halflives. Preliminary data are presented.
In this report, the quantitative relation between the height equivalent to a theoretical plate (HETP) and the size of ion exchange resin is studied by enriching lithium isotopes with high pressure ion exchange displacement chromatography. The dependence of HETP on the size of the resin can be expressed as H = C x (anti r)sup( ) in which = 2.4 and it is found that Snyder's equation is suitable for such a system of isotope separation as may be explained by the simple displacement mechanism.
We propose a continuum description for the axial separation of granular materials in a long rotating drum. The model, operating with two local variables, concentration difference and the dynamic angle of repose, describes both initial transient traveling wave dynamics and long-term segregation of the binary mixture. Segregation proceeds through ultraslow logarithmic coarsening. {copyright} {ital 1999} {ital The American Physical Society}
The purpose was to develop a simplified and reliable method of separating free from antibody-bound ligand using a precipitating antibody linked to a cellulose derivative. Dose-response curves and control sera were set up in parallel for various pituitary and placental polypeptides, steroid hormones, insulin, glucagon, triiodothyronine, thyroxine, angiotensin I, calcitonin, gastrin, cyclic AMP, and digoxin. After first-antibody reactions had reached equilibrium, free and bound ligand were separated using a double-antibody solid-phase system in parallel with conventional methods, including dextran-coated charcoal, double-antibody precipitation, single-antibody solid phase, organic solvents, salt precipitation, and anion-exchange resins. The effect of variations in temperature, incubation time, protein content, pH, and amount of separating material added were studied. The results showed that separation was ...
The purpose was to develop a simplified and reliable method of separating free from antibody-bound ligand using a precipitating antibody linked to a cellulose derivative. Dose-response curves and control sera were set up in parallel for various pituitary and placental polypeptides, steroid hormones, insulin, glucagon, triiodothyronine, thyroxine, angiotensin I, calcitonin, gastrin, cyclic AMP, and digoxin. After first-antibody reactions had reached equilibrium, free and bound ligand were separated using a double-antibody solid-phase system in parallel with conventional methods, including dextran-coated charcoal, double-antibody precipitation, single-antibody solid phase, organic solvents, salt precipitation, and anion-exchange resins. The effect of variations in temperature, incubation time, protein content, pH, and amount of separating material added were studied. The results showed that separation was ...
A device for laying cut peat in drying formations is proposed consisting of separate compartments, reinforced on a common frame and with mechanisms for both vertical and horizontal mixing. In order to intensify the drying process, within the scope of laying cut peat, uniform clearances and spacing in formations is applied. The mixing compartments are joined in sections with capabilities for separate mixing in each unit. The compartments are joined together by hinges and can be turned 180 degrees on the hinges horizontal to the plane.
This report presents the methodologies and results of the field/laboratory experiments and mathematical modeling defined for the phase III of the project. Results from test cases 2-6 are given in separate chapters of the report (which have been indexed separately), and the last chapter discusses the lessons learned from the three phases of the DECOVALEX project.
Biosorption means the storage of substances at the cell envelope. Different microbial biomasses were tested for the separation of radionuclides from mining waters. Results of a pilot plant demonstrate the ability of these techniques for water cleaning processes. An effluent concentration of lower than 1 mg/l (in most cases 0.1 mg/1) could be realized in a pilot plant by using pure cells of a methylotrophic strain of bacteria as well as using of a fungal mycelia.
During the past decades polymer membrane technology has been applied in various industries for a myriad of separation duties. They are also an important candidate for the solution of separation problems associated with the recovery of carbon dioxide in power plants. The application of membrane technology for carbon dioxide removal is discussed for two different ways of operation in present and future power plants. First, pressure driven operations are discussed, followed by a discussion of the use of membranes in absorbers. The pressure driven processes based on currently available gas separation membranes are shown to have poor separation characteristics. Further membrane development work appears to be necessary, especially in the area of temperature resistant membranes. Membrane selectivity goals are presented for present and future power plants. Membrane absorbers making use of commercially available ...
A numerical study of laminar flow and heat transfer in an array of stacked rectangular plates is presented. The array is placed in a uniform stream, and the plates are subjected to a constant surface heat flux. This flow configuration is relevant to a number of practical heat transfer devices with finned surfaces. The computations were performed using a finite volume solution of the steady, two-dimensional Navier-Stokes equations and energy equation. A numerical scheme that reduces numerical diffusion is used to discretize the equations. The dominant feature of the flow is the separation, and subsequent reattachment of, the boundary layer, which takes place at Reynolds numbers greater than about 75. The separation first occurs downstream of the leading edge of the plate; then as Re increases, the separation point moves upstream and remains fixed at the leading edge, and the reattachment length increases linearly with Re. ...
This paper addresses the problem of blind separation of convolutive mixtures of BPSK and circular linearly modulated signals with unknown (and possibly different) baud rates and carrier frequencies. In previous works, we established that the Constant Modulus Algorithm (CMA) is able to extract a source from a convolutive mixture of circular linearly modulated signals. We extend the analysis of the extraction capabilities of the CMA when the mixing also contains BPSK signals. We prove that if the various source signals do not share any non zero cyclic frequency nor any non conjugate cyclic frequencies, the local minima of the constant modulus cost function are separating filters. Unfortunately, the minimization of the Godard cost function generally fails when considering BPSK signals that have the same rates and the same carrier frequencies. This failure is due to the existence of non-separating local minima of the Godard ...
By using defined compositions based on industrial wastes of the hard-coal mining and a further waste material (red mud), which is obtained during the extraction process of alumina (BAYER-Process), it is possible to produce expanded-clay granulate requiring suitable preparation, shaping and firing at temperatures of about 1150 C. Some of the investigated parameters and aspects of this manufacturing process will be presented in this paper. (orig.) [German] Aus definierten Mischungen industrieller Reststoffe des Steinkohlenbergbaus (Bergematerial) mit einem weiteren Abfallstoff (Rotschlamm), der bei der Aluminiumoxidgewinnung nach dem BAYER-Verfahren anfaellt, laesst sich nach geeigneter Aufbereitung und Formgebung durch Brennen bei ca. 1150 C Blaehton-Grunulat herstellen. Auf einen Teil der untersuchten Parameter und ermittelten Zusammenhaenge soll im folgenden naeher eingegangen werden. (orig.)
The deregulation of the power industry having been implemented at unparalleled pace in Germany, the marketers and utility managers have been faced with the challenge of coping within relatively short time with the whole range of problems involved in restructurisation in the emerging competitive and very dynamic market. The article summarizes the activities for reorientation and positioning in the market, laying the foundation for success in the future. The communication and IT infrastructure is a major aspect to be considered. The authors explain how the German power industry may profit from international experience and results, so as to gain time in pulling up with competitors in the international marketplace. (orig./CB) [German] Die Liberalisierung der deutschen Stromwirtschaft kann im internationalen Vergleich als einzigartig sowohl hinsichtlich ihrer Breite als auch ihrer Geschwindigkeit - volle Marktoeffnung fuer alle Kunden auf einen Schlag - angesehen werden. Die schnelle ...
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 ...
In this study, the bend properties of the single-crystalline molybdenum brazed by using Mo-40%Ru alloys containing boron of 1-6 mass%Ru alloy for the improvement of the joint strength was determined. (orig.) [Deutsch] Durchgefuehrt wurde die Herstellung von Verbindungen aus einkristallinem Molybdaen. Hierbei kamen Mo-40%Ru-Legierungen mit 1 bis 6 Gew.-% Bor als Lotmaterialien zum Einsatz. Festigkeit und Duktilitaet der Verbindungen wurden mittels 3-Punkt-Biegepruefung bei Raumtemperatur und unter fluessigem Stickstoff ermittelt. Die Bruchflaechen der Proben wurden mit Hilfe eines Rasterelektronenmikroskopes untersucht. Die Ergebnisse lassen sich wie folgt zusammenfassen: Der optimale Borgehalt bezueglich Festigkeit und Duktilitaet der geloeteten Verbindung liegt bei 2 Gew.-%. Die entsprechende Probe hat bei einem Biegewinkel von 100 bei Raumtemperatur nicht versagt. Auch unter fluessigem Stickstoff zeigte diese Probe eine Festigkeit in der ...
The programme 'Solarthermie 2000' aimed at the testing and optimization of active solar systems, especially for service water heating. Sub-programme 2 was to provide the technical fundamentals and achieve a certain degree of standardization in order to make the technology economically competitive. This necessitated long-term monitoring of a representative number of systems. [German] Im Rahmen des Foerder- und Demonstrationsprogramms Solarthermie 2000, Teilprogramm 2 erfolgt durch die Foerderung von bis zu 100 solarthermischer Anlagen mit Schwerpunkt in den neuen Bundeslaendern eine umfassende Erprobung und Optimierung von Systemen zur aktiven thermischen Sonnenenergienutzung vorwiegend zur Brauchwassererwaermung. Mit dem Teilprogramm 2 sollen die technischen Voraussetzungen fuer einen kuenftigen wirksamen Beitrag der Solarthermie zur Energieversorgung geschaffen und durch Systemstandardisierung die wirtschaftliche ...
Computerized descriptions of isothermal, multi-stage creep fatigue load were established for one melt each of steels of the type 1%CrMoNiV and 12%CrMoV and were implemented in the service life prediction program SARA 2. SARA 2 predicts the time and number of cycles to incipient cracking for a given number of part cycles on the basis of rules for description of cyclic deformation and damage and of a generalized damage accumulation hypothesis. [German] Fuer je eine Schmelze der Staehle vom Typ 1%CrMoNiV and 12%CrMoV wurde eine rechnergestuetzte Beschreibung fuer isotherme mehrstufige Kriechermuedungsbeanspruchung erstellt und in ein Lebensdauerzaehlerprogramm SARA 2 implementiert. Auf der Grundlage von Regeln zur Beschreibung von zyklischer Verformung und Schaedigung unter Anwendung der verallgemeinerten Schadensakkumulationshypothese ermittelt SARA 2 fuer beliebig vorgebbare Teilzyklen einen Vorhersagewert fuer die Anrissdauer und die ...
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 Hochspannungsbetriebsmitteln ...
Purpose: calculation of conversion coefficients for the reconstruction of organ doses from entrance doses for abdomen radiographs of 0, 1, 5, 10, 15, and 30-year-old patients in conventional pediatric radiology for the radiographic settings recommended by the German and European guidelines for quality management in diagnostic radiology. Materials und method: using the commercially available personal computer program PCXMC developed by the Finnish Center for Radiation and Nuclear Safety (Saeteilyturvakeskus STUK), conversion coefficients for conventional abdomen radiographs were calculated performing Monte Carlo simulations in mathematical hermaphrodite phantom models describing patients of different ages. The possible clinical variation of beam collimation was taken into consideration by defining optimal and suboptimal radiation fields on the phantoms' surfaces. Results: conversion coefficients for the reconstruction of organ does in about 40 organs and tissues of the human ...
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...
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 ...
Modern oscillation- and analysis systems are often mentioned in the context of oscillation diagnosis which implies that this is a method of establishing the causes of the mechanical changes that cause the unwanted oscillation. Experience shows, however, that oscillation monitoring instruments can merely indicate oscillation symptoms at an early point in time. These findings must be interpreted in a machine-specific way and seen in the context of previous developments in order to establish the mechanical root cause of the matter. A 1000 MVA-generator shows that conventional oscillation measuring systems may also serve for diagnostic purposes within certain limits.(orig.) [German] Im Zusammenhang mit modernen Schwingungsmess- und Analysensystemen wird haeufig der Begriff der Schwingungsdiagnose verwandt und inpliziert, damit auch die Ursache von mechanischen Veraenderungen finden zu koennen, welche das beanstandete Schwingungsverhalten hervorruft. In der Praxis zeigt ...
Until now, monitoring of power transformers focussed mainly large generator and network transformers. Siemens goes a step ahead and provides a system especially developed and designed for small and medium power transformers, e.g. for the 100 kV level. This low cost version could be achieved by restriction to really necessary measuring quantities. This allows to realize also for small and medium power transformers an online monitoring including an estimation of aging and as an option an early warning to avoid unexpected failures. (orig.) [German] Die Ueberwachung (Monitoring) von Leistungstransformatoren war bisher vor allem fuer Maschinentransformatoren und grosse Netzkuppeltransformatoren in der Diskussion. Siemens geht einen Schritt weiter und stellt nun auch ein System bereit, das speziell fuer kleine und mittlere Leistungstransformatoren, z.B. der 110-kV-Spannungsebene, konzipiert ist. Diese kostenguenstige Variante wurde durch Beschraenkung auf die aus ...
Leakfree compression of gaseous liquids prevents impurities resulting from entry of lubricants and abrasive particles and is therefore an important requirement on modern compressors. Another requirement voiced increasingly often is the reduction or even prevention of problematic off-gases and contaminated residues of libricating oils. Further, compressors should have high corrosion resistance, low noise, a long service life and high reliability. Membrane compressors are largely able to meet these requirements. The article describes the technical concept and applications of membrane compressors. (orig.) [Deutsch] Umweltschutz und steigende Forderungen der Industrie an die Reinheit technischer Gase verlangen Kompressoren, die weitgehend leckagefrei verdichten und keine Verunreinigungen des Gases durch Schmierstoffe und Abrieb hervorrufen. Immer haeufiger wird in diesem Zusammenhang die Reduzierung oder sogar die Vermeidung von schwer zu entsorgenden Abgasen und ...
Meltdown and gasification of waste in an oxygen atmosphere ('2sv' process) is an economically efficient alternative to energetic and thermal utilisation of biomass. Organic pollutants are split at temperatures up to 2000 C in a reducing atmosphere. The process uses elements of the oxygen cupola furnace for melting and gasification of many different waste fractions, e.g. polluted waste wood, household refuse and bulk waste, old tyres, light shredder fractions, sewage sludge, etc. [German] Die Sauerstoff-Schmelz-Vergasung ('2sv') stellt eine wirtschaftliche Alternative zur energetischen Nutzung von Biomassen wie auch zur thermischen Abfallverwertung dar. Organische Schadstoffe werden bei diesem neuen Verfahren bei Temperaturen bis zu 2000 C unter reduzierenden Bedingungen aufgespalten. Das Verfahren nutzt Elemente des Sauerstoff-Kupolofens fuer die Schmelzvergasung und eignet sich fuer zahlreiche Abfallarten wie z.B. belastetes ...
Verification of guarantees mostly calls for measurements on the spot. The paper deals with the guarantees that apply to small hydroelectric power stations. Already when planning a plant it should be decided what guarantees are to be demanded and how they can be verified. Specifically, measurements to verify guaranteed performance and efficiency on the spot are dealt with. Details are not given. Rather, the report wants to give an overview of methods and aspects to be taken heed of. For in-depth information, the reader is referred to the corresponding standards and guidelines. (orig.) [Deutsch] Zur Ueberpruefung von Garantien ist meistens die Durchfuehrung von Messungen vorort notwendig. Es werden die Garantien behandelt, die bei Kleinwasserkraftanlagen in Frage kommen. Bereits bei der Planung der Anlage sollte entschieden werden, welche Garantien gefordert werden sollen und wie sie ueberprueft werden koennen. Es wird speziell auf die ...
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 ...
Zusammenfassung Hintergrund Die vorliegende Arbeit untersucht, welche Frequenzkombination f?r die Berechnung der mittleren H?rverluste im Tonschwellenaudiogramm am besten mit dem H?rverlust f?r Zahlen im Sprachaudiogramm korreliert, da in der Literatur verschiedene Rechenvarianten f?r diese gutachterliche Plausibilit?tspr?fung beschrieben werden. Es wurden die 3?Rechenvarianten A (250, 500 und 1000?Hz), B (500 und 1000?Hz) und C (500, 1000 und 2000?Hz) verglichen. Methoden Die Audiogramme von 80?Normalh?rigen, 106?Schwerh?rigen und 135 zu Begutachtenden wurden retrospektiv analysiert. Die Differenzen der Mittelwerte aus dem Tonschwellenaudiogramm und dem H?rverlust f?r Zahlen wurden f?r das rechte und linke Ohr getrennt in den 3?Patientenkollektiven berechnet und statistisch verglichen. Er...
Until recently no active treatment for advanced or metastatic gastrointestinal stroma tumors (GIST) was available. The tyrosine kinase inhibitor imatinib has revolutionized the treatment of this disease and the median overall survival now reaches 5 years. The standard dose of imatinib is 400 mg per day. Locally advanced GIST should be treated with systemic therapy prior to surgical resection. Imatinib was recently licensed for adjuvant therapy following complete surgical removal of GIST in patients with a significant risk of recurrence. (orig.) [German] Bis vor einigen Jahren existierte keine wirksame systemische Therapie fuer fortgeschrittene oder metastasierte gastrointestinale Stromatumoren (GIST). Der Tyrosinkinaseinhibitor Imatinib hat die Behandlung dieser Tumoren revolutioniert, die mediane Ueberlebenszeit liegt heute bei etwa 5 Jahren. Die Standarddosierung von Imatinib betraegt initial 400 mg/Tag. Lokal fortgeschrittene Tumoren werden primaer systemisch ...
The new multi-purpose oxygen cupola furnace is a coke-fired shaft furnace that is operated on pure oxygen. The top gas is recirculated, and the fumes are drawn off at temperatures ranging from 800 to 1 000 C. The furnace offers the possibility of melting down contaminated and zinc-bearing scrap without the occurrence of any environment-polluting gas emissions. The absence of nitrogen ballast permits a high energy efficiency. (orig.) [Deutsch] Der neue Mehrzweck-Sauerstoff-Kupolofen ist ein koksbeheizter Schachtofen, der mit reinem Sauerstoff betrieben wird. Das Gichtgas wird im Kreislauf gefuehrt, und das Abgas wird aus einem Bereich mit Temperaturen von 800 bis 1 000 C abgefuehrt. Der Ofen bietet die Moeglichkeit, verunreinigte und zinkhaltige Schrotte einzuschmelzen, ohne dass umweltbelastende Gasemissionen auftreten. Der fehlende Stickstoffbalast bewirkt einen hohen energetischen Wirkungsgrad. (orig.)
An analysis on landscape level was performed to investigate the growth of Scots pine stands (Pinus sylvestris L.) in the research area of 'Duebener Heide' under the impact of rapidly changing pollution loads and to evaluate their further development. Central to the work was a spatial database, installed using a geographic information system (GIS). This database enabled the statistical analysis of relationships and correlations between the growth of the pine stands, the influence of pollution impacts and the natural site characteristics. The results of emission and immission modelling gave detailed evaluation of the pollution load over the investigated area. The spatial information database was linked with a process-based growth model called FORSANA. The resulting regional model was used to simulate forest growth on stand level for variable time periods. The plausibility of the simulation results of the model was checked for the influence of different patterns of ...
Suppliers of systems and components for compressed air technique were shown at the Hanover Fair 94 in Hall 5. On about 6000 m{sup 2} floor area, they showed their product range, which covered the whole range of compressed air technique from compressors via equipment for providing and storing the compressed air to compressed air tools. (orig.) [Deutsch] Die Anbieter von Systemen und Komponenten fuer die Drucklufttechnik waren auf der Hannover-Messe `94 in der Halle 5 zu finden. Dort zeigten sie auf rund 6000 m{sup 2} ihre Produktpalette, die von Kompressoren ueber die Geraete zum Aufbereiten und Speichern der Druckluft bis zu Druckluftwerkzeugen reichte und den gesamten Bereich der Drucklufttechnik abdeckte. (orig.)
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 ...
Internal combustion engines with mechanically driven superchargers are known for good performance at low engine speeds and fast response times under fluctuating loads. Application engineers can choose between superchargers with and without internal compression - the familiar roots (blower) type or true compressors - for supercharging an internal combustion engine. This article by DaimlerChrysler describes two options for improving the partial load behaviour of mechanically supercharged internal combustion engines with compressors. (orig.) [German] Die Aufladung mit mechanisch angetriebenen Verdraengerladern zeichnet sich durch guten Druckaufbau bei niedrigen Drehzahlen und gute Dynamik bei Lastwechseln aus. Fuer die Applikation am Verbrennungsmotor koennen Maschinen ohne innere Verdichtung - wie die bekannten Roots-Geblaese - oder Maschinen mit innerer Verdichtung - Kompressoren im eigentlichen Sinne - zum Einsatz kommen. In diesem Beitrag von DaimlerChrysler sind ...
The results of the experiments on the pressure oxidation of oil and fat in waste waters shows that the final COD and TOC values decrease with growing temperature and reaction time and decreasing initial concentration. Oxidation of oil and fat in waste water is no straight forward procedure. Therefore it should be compared in the individual case with laternative methods in terms of cost and economic efficiency. (EF) [Deutsch] Die Ergebnisse der Versuche zur Druckoxidation von Oel und Fett in Abwaessern zeigten, dass sich die CSB- und TOC- Endkonzentration verringerte mit steigender Temperatur, Reaktionszeit und verringerter Ausgangskonzentration. Die Oxidierbarkeit von Oel und Fett in Abwaessern ist sehr schwierig. Deshalb sollte in jedem Einzelfall ein Vergleich mit alternativen Verfahren bezueglich Aufwand und Wirtschaftlichkeit vorgenommen werden. (EF)
This paper provides some results of the research works at low pressure components of steam turbines and some construction solutions resulting in a modernisation. The problems of turbine phases for the transonic flow are analysed with respect to reducing profile and margin losses. The origin and flow of wet steam and its influence on corrosion and erosion is investigated. Inlet and outlet casing of the flow channels and transfer diffuser between second last and last phase are mentioned. (orig.) [Deutsch] Im Beitrag werden einige Ergebnisse der Forschung der Teile von ND-Teilen der Dampfturbinen angegeben, und werden irgendeine Konstruktionsloesungen, die fuer ihre Modernisierung guenstig sind, beschrieben. Kurz wird die Problematik der Turbinenstufen fuer die transsonische Stroemung analysiert, mit Hinsicht auf die Erniederung der Profil- und Randverluste. Weiter ist die Aufmerksamkeit der Entstehung und Stroemung des Nassdampfes im Zusammenhang mit dem Phaenomen ...
The investigations showed that the new adsorber/catalyst composites are well suited for chemical degradation of persistent water pollutants. Compared with alternative processes, the reaction selectivity and the consumption of oxidant are more favourable as the reaction now takes place on/inside the solid. The process, which was developed originally for purification of contaminated water, can be transferred to many other systems of materials. For example, it is expected that the soot emissions of diesel engines will be reduced significantly after efficient hydrogenation of the aromatics contained in the diesel engine on molybdenum-charged mesoporous composites. [German] Mit den vorliegenden Untersuchungen konnte ein erster Nachweis gefuehrt werden, dass die neu entwickelten Adsorber/Katalysator-Komposite fuer den chemischen Abbau persistenter Wasserschadstoffe geeignet sind. Im Vergleich zu alternativen Verfahrensloesungen kann die Selektivitaet der Reaktion und der Verbrauch an ...
Ventilation systems must ensure high room air quality with minimum energy consumption in all states of operation. Systems for ventilation on demand are increasing their market share. (orig./MSK) [Deutsch] Oberste Aufgabe von Raumlufttechnischen Anlagen ist die Sicherstellung guter Raumluftqualitaet bei minimalem Energieverbrauch unter allen Betriebsbedingungen. Um dieses Ziel zu erreichen, setzt sich am Markt zunehmend die bedarfsgeregelte Lueftung durch. (orig./MSK)
In the last two years, the VDMA work group 'Functional security' compiled a qualitative and quantitative procedure for the determination and evaluation of turbo-machine specific risks. With the calibrated risk graph for turbo-machines the requirements (Safety Integrity Level SIL) to the protective functions for turbo-machines (steam turbines, gas turbines, generators and compressors) were determined. With consideration of the legislation, the work group compiled a recommendation for the renewal and/or reconstruction of protective functions with old facilities.
This report contains two sections. In the first section a limited review is presented and the preparation of the red mud based additives is described. The additives are characterized by composition and their catalytic activity in hydrocracking is investigated in a batch autoclave under an initial hydrogen pressure of 12 MPa at 435 C and 30 min residence time. A quantitative characterization of the products is given. Comparisons between the red mud additives and coke respectively a commercial catalyst are made. (orig.)
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 ...
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 ...
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 ...
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 ...
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 ...
In order to ensure a power balance in an electrical network a spinning reserve has to be capable of activation within seconds. However, because of the need to vary the fuel flow in the steam generator, the run-up of output takes minutes. The required capacity response is therefore achieved by storage of steam from the steam generator. In this process the turbine control valves come into action in a specific manner. The paper describes the importance of the initial reserve for unit capacity control. (orig.).
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 ...
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 ...
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 ...
Westinghouse Electric Germany GmbH has developed fluid dynamic models for medium-actuated armatures using the thermal hydraulic code RELAP5 in order to reach a more realistic description of the armature behavior including fluid-structure interactions in case of transient flow conditions in piping systems. The contribution is concerned with the modeling of damped check valves. The model allows the description of the behavior during opening and closure of a check armature. The calculated results show good agreement with the available measured data.
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 ...
This thesis dealt with the metal-organic gas phase epitaxy with nitrogen as carrier gas. For this first by means of three-dimensional modelings of the epitaxy process the influence of the carrier gas on the processes was explained. The optimization of the growth parameter for the whole light-emitting-diode structure in double-hetero arrangement resulted that an a temperature of 770 C and a V/ III-ratio of 150 layers with a high crystal quality could be reached.
Smooth and notched specimens of the bearing steel 100Cr6 (SAE 52100) in a bainitic condition were used to determine the S-N-curves under tensile, torsional and combined in- and out-of-phase loading. In the area of high-cycle-fatigue, crack initiation was most likely caused by inclusions like Titanium Carbonitrides or Aluminium Oxides. A model was developed to describe the influence of the magnitude of these inclusions on the lifetime. A weakest link model, using the statistical distribution of inclusions and surface flaws, was used to describe the fatigue limit. (orig.)
The report covers the results of exposing materials for steam turbines to increased steam temperatures in two modules of the KOMET 650 testing facility at the Westfalen power plant. Ferritic/martensitic steels with 9 to 12% Cr and austenite and nickel-based alloys were investigated. Some experimental coatings on low-alloy Cr steel were also tested. The principal findings are presented. It will become possible to construct advanced power stations to be operated at higher temperatures. (orig.)
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 ...
The restricted temperature stability of the synthetic thermal oil which is used as heat carrier fluid in parabolic trough collectors so far limits the live steam parameters in the steam cycle to approximately 375 Celsius. In order to break through this limit, already for quite some time it is researched to replace the thermal oil by boiler feeding waters and to accomplish the evaporation in the collectors. The contribution under consideration gives an overview on the direct evaporation concept and summarizes the past operational experiences. Moreover, the challenges with the integration of this technology in a steam turbine cycle are elaborated.
Two hypotheses are in the centre of this investigation, on the one hand the question, whether microwaves as exogenous fields alone are able to stimulate human muscle cells above-threshold, and on the other hand, whether microwaves as conditioning to cathodical electrical pulses can modify the excitation threshold and form. No excitation through the application of microwaves alone can be introduced at any subject. The conditioning of above-threshold cathodical electrical pulses with UMTS-microwaves leads not to a transgression of the threshold or the electrical muscle response (EMG) depending on the amplitude, the duration or the dose rate. (orig.)
Thermal solar energy plants for water heating have experienced an enormous boom during the last years. Thus, a total of 200000 square metres of collector surface was installed on German rooves in 1991. This was three times as much as in the year before. And this trend of conserving natural resources by using the energy of the sun is still undiminished. (orig.)
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.)
The legal basis to be provided is a licence for decommissioning work, issued for a particular reactor, including activities for recycling of disassembled, radioactive components and materials, subject to radioactivity measurements and exemption from radiological control of materials not exceeding the legally defined maximum level of contamination. (HP) [Deutsch] Es genuegt eine Stillegungsgenehmigung zu einem konkreten Abbauauftrag mit Verwertung radioaktiver Reststoffe nach Freigabe durch Radioaktivitaetsgrenzwertsfestsetzung. (HP)
Higher efficiencies of steam power plants are achieved by raising the operating temperature and pressure. The use of ferritic steels helps to minimize the cost and enhance the flexibility (two-shift operation, frequent starting and stopping). The COST programme had the long-term goal of developing and testing 9- 12 % Cr steels with high fatigue strength and to produce,test and operate critical components for an advanced steam power plant (steam temperature 600 C and supercritical pressure). (orig.)
In order to improve the capacity and service life of cathodes, the effect of carboxy-methyl cellulose, soot, silica gel and fibres was examined. Structural tests and electrical and electro-chemical measurements are used for this. The additives can affect crystallization in the manufacturing stage of the electrodes and can increase the storage capacity for water and the electronic conductivity. They act to stabilize the mass in cyclic operation. Soot additive has little effect on the properties of the electrode, but the other substances increase the service life or the use of the mass. (LU).
Since mid-1995, Audi is the second European producer to offer a direct-injection diesel engine for passenger cars. The 2.0 l engine is installed in the middle-class sedan Rover 620 SDi. (orig.) [Deutsch] Als nach Audi zweiter europaeischer Hersteller bietet Rover seit Mitte dieses Jahres einen Pkw-Dieselmotor mit direkter Einspritzung an. Eingesetzt wird das Aggregat mit 2,0 l Hubraum in der Mittelklasselimousine Rover 620 SDi. (orig.)
In recent years very good experience has been accumulated with self-supporting low-pressure blades. Today blades are constructed up to a length of 1060 mm (50 Hz) or 1360 mm (25 Hz). In this process modern computational methods from aerodynamics and also from mechanics are employed. The further development of computer technology also permits new methods, for example the use of curved fixed blading as well as the optimization of existing designs. (orig.).
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 ...
The invention concerns the conversion of steam turbines, particularly condensation turbines, for the economic coupling of process steam and heating steam. The conversion occurs by retaining the basic construction of foundations, housing and bearings as support group and coupling member and matching the specially developed construction for the idea of use into the existing housing, and inserting the rotor into the shaft unit. By having the unchanged supports of the housing and the bearings of the shaft unit, the elasticity in expansion and the vibration behaviour of the turbine are retained and the conversion costs can be lowered.
There is increasing demand to functionalize meso- and nano-porous materials by coating and make the porous substrate biocompatible or environment friendly. However, coating on a meso-porous substrate poses great challenges, especially if the pore aspect ratio is high. In the current work the pulsed laser deposition (PLD) method is used for coating Ni{sub 3}Al-based meso-porous membranes with diamond-like carbon (DLC) layers of high thickness homogeneity and adhesion. (orig.)
We studied 129 AIDS patients with suspected or proved intracranial manifestations of the disease. The purpose of this study was to compare the diagnostic sensitivity of unenhanced and contrast enhanced CT and unenhanced T{sub 2}-weighted MR. Thus, in 20% of our patients MR but not CT was diagnostic. In another 20% MR provided additional diagnostic information. In conclusion, MR is recommended as the imaging modality of choice in AIDS patients with non-conclusive cranial CT. (orig./GDG).
Biogas supply to the public gas grid is a new option discussed in the most recent publication of Fachagentur Nachwachsende Rohstoffe (FNR) e.V. The biogas is purified, upgraded to natural gas quality and fed into an existing gas grid. Once there, it can be transported across long distances and also used for electric power generation at the consumer side. The study investigates inhowfar and in what instances this method is feasible and promising. It discusses the technical background and the regional potential of biogas. Seven model biogas systems are presented as examples. (orig.)
The comprehensive survey explains the indications and the specific value of the modern tomographic modalities with respect to the various diagnostic issues. Numerous reproductions of CT, MRI, US scans illustrate the aspects discussed. (orig./CB) [German] Bildgebende Verfahren kommen bei der Abklaerung von Erkrankungen des weiblichen Urogenitaltrakts ergaenzend zu der klinischen Untersuchung zur Anwendung. Kongenitale Uterusanomalien werden primaer mit der HSG oder der Laparoskopie diagnostiziert. Zusaetzlich koennen der transvaginale US und in unklaren Faellen die MRT eingesetzt werden. Die Diagnose entzuendlicher Erkrankungen des weiblichen Genitaltrakts erfolgt in der Regel klinisch. Schnittbildverfahren werden bei therapieresistenten, komplizierten Faellen angewendet. Initial werden benigne Neoplasien des Uterus mit dem transvaginalen US abgeklaert. Eine Verdickung des Endometriums ist dabei ein unspezifischer Befund und kann auf eine Hyperplasie, Polypen oder ...
Materials and methods: 12 patients with 22 coronary bypass grafts underwent intraoperative flow quantification using the transit time ultrasound method. These values were compared to postoperative MR phase shift measurements. Flow measurements were performed preoperatively in 28 coronary arteries of 20 patients. For flow measurement, we used a velocity-encoded k-space segmented gradient echo sequence with a temporal resolution of 110 or 125 ms, respectively. 6-8 pase shift images could be acquired during one cardiac cycle. Results: There was a significant correlation between intraoperative and flow measurements using velocity-encoded MR imaging (r=0.76, p<0.0001, t-test). Flow volumes determined by MR imaging were systematically larger than those determined by the transit time ultrasound method. Mean flow in coronary arteries was reduced in severely stenosed vessels (>70%) compared to normal vessels. Intra- and interobserver variability were 10.5 and 15% (coronary bypass ...
The first biogas plant using the Plauen method has been operated without failures in the Saxon Vogtland since May 1987. This large scale anaerob treatment plant which is the first one in Germany handles besides agricultural recidual substance both municipal and industrial organic residues. The results show clearly that fermentation is a real alternative to composting, combusting and deponing. (orig.)
The development of new steels is always a challenge for the manufacturer of filler metals. In many cases it is obvious that some properties of the base metal cannot be fulfilled with matching filler metals. In some cases, dissimilar filler metals can solve the problem in some cases, there is no chance to meet the requirements of the base metal (for example yield strengths of new ultra high strength steels). This paper deals with different kinds of new steels and the requirements for the weld metal with examples from motor car industry (Mangan Austenite), crane (Ultra high strength steels), earthmoving machinery (Wear-resistant steels) and offshore (Supermartensitic steels). Specific problems will be discussed and best solutions will be highlighted. These examples make clear that the success of new kinds of steels in the market depends on solving the joining problems of these steels. (Abstract Copyright [2007], Wiley Periodicals, Inc.) [German] Die Entwicklung von ...
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 bei Temperaturen ...
The nozzle-group regulation of steam turbines plays furtheron an important role in the operation of power stations owing to modern, adaptable control-technical valve timing possibilities. New procedures for a choice-connection of different nozzle areas via the control valves as well as the use of valve laps require, however, a differentiated consideration of the loss mechanism in the inlet area of the turbine, in order to be able to assess and minimize its specific heat consumption also at the operational points outside the layout- and calculation-technically fixed guarantee or valve points, respectively. The basic technical-physical stages to this are explained. (orig.) [Deutsch] Die Duesengruppenregelung von Dampfturbinen nimmt nicht zuletzt dank moderner, anpassungsfaehiger leittechnischer Ventilansteuerungsmoeglichkeiten weiterhin eine bedeutende Stellung beim Betrieb von Kraftwerken ein. Neue Verfahren zur wahlweisen Zuschaltung ...
The typical MRI features of the most common pancreatic diseases, such as pancreatitis and adenocarcinoma of the pancreas, have been established. However, even in these common pancreatic disorders, MRI correlation with the underlying pathology is limited for clinical reasons. We emphasize MR-pathological correlation of inflammatory and neoplastic pancreatic changes, including pancreatitis, adenocarcinoma, acinar cell carcinoma, rare cystic and solid pancreatic neoplasms, and islet cell tumors. By highlighting the correlation of key pathological features with MR findings, a better understanding of the MR appearance of pancreatic pathology can be provided. In addition, MRI may prove a powerful tool in detection and characterization of pancreatic tumors. (orig.) [Deutsch] Das MR-tomographische Erscheinungsbild von Pankreatitiden und Adenokarzinomen des Pankreas, als den haeufigsten Pankreaserkrankungen, ist zwar ausreichend bekannt; allerdings ist selbst bei diesen ...
As a partner in this project, Siemens Power Generation investigated the crack propagation characteristics of short cracks in CMSX4. This involved crack propagation tests under dynamic and static load, creep tests on samples of different geometries, and life calculations, with the following results: No typical short cracking behaviour was observed under dynamic loads. Short crack propagation at 950 C under static load is well described by the fracture mechanical parameter C* integral. Notched bar creep tests showed longer times to cracking for notched bars. [German] In dem Verbundprojekt hat Siemens Power Generation u.a. die Untersuchungen von Rissausbreitungsverhalten von Kurzenrissen in CMSX4 als Hauptaufgabe bekommen. Dabei wurden Rissausbreitungsversuche unter dynamischer und statischer Belastung, Kriechversuche an Proben verschiedener Geometrie und Lebensdauerberechnung durchgefuehrt. Die wesentlichen Ergenisse sind wie folgt kurz ...
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 ...
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 anterius (TFA) und ...
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 ...
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, ...
The low budgets of local governments and Federal States in Germany as well as lack of financial means of renters delaying thorough modernisation of existing heating systems in residential and public buildings, novel heat supply and related customer services are emerging on the market. Heat supply companies and housing construction associations increasingly use modern electronics and telecommunication systems for heating system upgrading and reliable operation and maintenance. This option holds an enormous potential of saving money today and in the future. Installation of remote control and maintenance systems and the related telephone-based services offer fast repair and other services via electronic telecommunications systems, thus saving money and manpower for the repair services of heat suppliers or plumbers, or financial losses due to rents being docked for broken down heating systems. Such remote control and maintenance systems however need to be reasonable in price, and versatile ...
Owing to their key function in power production the technology of gas- and steam turbines has a very high importance. Gas turbines in particular have become much more efficient and show higher performance in cogeneration plants. The VDI group on materials engineering puts these issues at the centre of this report whose focus is on measures necessary to increase plant availability: damage analysis, materials optimisation, supervision of construction and repair. The report which looks at applications and practical experience is adressed to operators of gas-, steam-, and water turbine plants, manufacturers of turbines and their components as well as maintenance companies, experts and insurance engineers. (orig.) [German] Aufgrund ihrer Schluesselposition bei der Stromerzeugung kommen den Gas- und Dampfturbinen eine sehr hohe technische Bedeutung zu. Insbesondere die Gasturbine macht in den letzten Jahren eine rasante Entwicklung im Hinblick auf Erhoehung von ...
Alloyed steels containing retained austenite after martensitic hardening are widely applied in technical practice. Although many practical investigations have been made into the mechanical behaviour of composite microstructures with retained austenite, there is still a lack of knowledge concerning their fatigue and crack propagation behaviour. For this reason, the author investigated the effects of retained austenite concentration and stability on the transformation and deformation behaviour of hardened states of the steels X210Cr12 and 100Cr6. For this purpose, monotone tensile tests, cyclic tensile pressure tests, and supplementary crack propagation experiments were carried out. The concentrations of retained austenite were varied between 10 and 100% by volume by means of different heat treatments. [Deutsch] Legierte Staehle, die nach martensitischer Haertung noch Restaustenit enthalten, finden in der technischen Praxis verbreitete Anwendung. Zum mechanischen Verhalten ...
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 ...
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 ...
High-strength, fully hardening steels are used in general for applications involving severe wear and frequently also additional cyclic stress. For the latter condition, the available information and experimental data for component dimensioning are insufficient. Work reported in the dissertation therefore was intended to establish experimental information showing the performance of the bainitic roller bearing steel 100Cr6 and deducing rules of applicability to components, of the fatigue strength data obtained with the specimens. Various models for calculating the fatigue strength are presented together with their application to the steel 100Cr6. The results show that the weakest link model is a good concept for fatigue strength calculation, taking into account multiaxial loading. (orig/CB) [Deutsch] Hochfeste durchhaertende Staehle unterliegen in der Regel hohen Verschleissbeanspruchungen und werden darueber hinaus oftmals zusaetzlich schwingend beansprucht. Fuer die schwingende ...