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  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 71 (2000), S. 836-838 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: For the International Fusion Materials Irradiation Facility (IFMIF) scenario, a 140 mA deuterium beam in continuous wave (cw) mode with an atomic yield of above 85% is required. The normalized root-mean-square emittance should be less than 0.2 π mm mrad at the entrance of a RFQ. As part of a conceptual design for IFMIF, a new ion source has been developed and is tested at the Institut für Angewandte Physik in Frankfurt. The ion source is of the volume type with a tungsten cathode driving the discharge. Both cw and pulsed mode are possible and were studied. First experiments were carried out with deuterium. 80 mA deuterons with a D+ fraction of above 90% were extracted [A. Maser et al., Rev. Sci. Instrum. 67, 1054 (1996)]. In order to avoid neutron generation by the d–d reaction, hydrogen was used instead of deuterium later on. As far as the ion source and plasma production processes are concerned, the use of hydrogen instead of deuterium is equivalent because of their similar atomic shells. Recently, a 200 mA proton beam at 55 kV was extracted in cw mode (according to Child–Langmuir, 200 mA H+ corresponds to 140 mA D+) with a H+ fraction of 93%. This article will give a detailed description of the ion source and the essential experimental results. Especially, the influence of important physical parameters (such as discharge current and strength of the filter field) on the H+ fraction was studied. By using different kinds of auxiliary gases, the influence on the H+ fraction and the noise level were investigated, too. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 73 (2002), S. 1027-1029 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: For the International Fusion Materials Irradiation Facility project (IFMIF) the Institut für Angewandte Physik at the University of Frankfurt is concerned with developing a high current proton/deuteron ion source. The 1999 "Frankfurt 200 mA Proton Source" is a volume type belonging to the high-efficient ion-sources family. This type of ion source has proven its capability to produce high-current ion beams of a single mass-to-charge ratio at very low-beam emittances. The arc discharge ion source delivers a 200 mA full beam (93% protons) at 55 keV with very high-beam intensities (outlet aperture 8 mm diam). Thus, the beam requirements for the IFMIF project are fulfilled. After having done the basic plasma investigation with a 127° cylinder spectrometer, the quality of the ion beam was a point of interest. Therefore, the beam emittance was measured with a conventional slit-grid measurement device. The goal was to measure the beam emittance at high-beam currents. The article will give a detailed description of the measurement of a 56 mA beam at 26 keV with 85% protons. Theoretical considerations of the emittance value, given by ion temperature and aberrations of the extraction system, allows an estimation of the emittance of a 170 mA at 55 keV proton beam. In a second step, an estimation of a postaccelerated 140 mA at 100 keV deuteron beam was completed. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of the American Chemical Society 99 (1977), S. 5187-5189 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Inorganic chemistry 14 (1975), S. 473-477 
    ISSN: 1520-510X
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 33 (2000), S. 1162-1174 
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: The instrumental transparency functions of five commercially available texture goniometers were measured experimentally with six monocrystalline samples cut in different orientations from a large highly perfect silicon crystal with a rocking curve of less than 0.01°. Transparency functions were measured in steps of 0.02 to 0.2° in the pole-figure angles α, β. The window size Δα depends on the Bragg angle θ in the form 1/sinθ; the window size Δω is constant for each goniometer. The dominant instrumental parameter determining the long axis Δα of the pole-figure window is the axial width of the detector entrance slit. This parameter is smallest for area detectors (smaller by more than an order of magnitude compared with conventional scintillation detectors as well as one-dimensional position-sensitive detectors). The main features of the pole-figure window and their dependence on the instrumental parameters can be deduced fairly well from a simple geometrical model. The particular shapes of the transparency functions of the studied goniometers are markedly different. Particularly, they are not very well represented by Gauss functions. The two-dimensional transparency function can be fairly well characterized by its α and β profiles. The normalized profiles are virtually independent of the goniometer angles 2θ and α. The increasing size of the pole-figure window with decreasing θ puts a lower limit on the Bragg angle below which pole-figure measurement ceases to be meaningful.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Physiologia plantarum 45 (1979), S. 0 
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Free and total putrescine and, to a lesser extent, spemidine accumulate in both roots and shoots of peas in response to potas stum deficiency and ammomnium supply. Free putrescine responds more sensitively than total putreseine to variatioin of nutrients. Accumulation of putrescine is more pronounced in the roots than in the shoots.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Colloid & polymer science 255 (1977), S. 927-927 
    ISSN: 1435-1536
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1435-2451
    Keywords: Selective proximal vagotomy ; Pyloric stenosis ; Pyloroplastic ; Gastric emptying ; Acid secretion ; Serum gastrin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Mit einer modifizierten intestinalen Perfusion- und Aspirationsmethode wurden simultan die motorischen and sekretorischen Magenfunktionen nach Gabe einer flüssigen Testnahrung beim wachen Miniaturschwein nach experimenteller Pylorusstenose, alleiniger SPV, SPV mit zusätzlicher Pylorusstenose und SPV mit zusätzlicher Pyloroplastik untersucht. Nach alleiniger SPV fand sich eine initial betonte Abnahme des intragastralen Volumens und eine normale Entleerung in das Duodenum. Bei einer zusätzlichen Pylorusstenose trat keine signifikante Änderung ein. Eine Pyloroplastik führte zu einer signifikanten Anhebung des intragastralen Volumens mit verzögerter Entleerung. Die durch eine SPV reduzierte postprandiale Säuresekretionsleistung wurde weder durch eine Pyloroplastik, noch durch eine Pylorusstenose signifikant verändert. Das basale Serumgastrin war sowohl nach SPV als auch nach SPV in Kombination mit einer Pylorusstenose oder Pyloroplastik erhöht. Nach Nahrungsstimulation kam es zu einem verzögerten Anstieg des Serumgastrins nach SPV, der sich lediglich in der ersten Stunde von den Werten nach SPV mit Pylorusstenose oder Pyloroplastik unterschied. Die vorliegenden Ergebnisse lassen erkennen, daß bei einer SPV durch eine zusätzliche Pyloroplastik keine weitere Verbesserung der sekretorischen und motorischen Funktionen erzielt wird. Weiterhin lassen die erhobenen Untersuchungen den Schluß zu, daß nach SPV mit einer zusätzlichen experimentellen Pylorusstenose keine Entleerungsverzögerung des Magens auftritt und die postoperative Säuresekretion und das Serumgastrin nicht negativ beeinflußt werden.
    Notes: Summary In conscious fullgrown minipigs simple SPV alone, SPV and pyloric stenosis and SPV and pyloroplasty were performed. After a liquid test meal the motoric and secretory function of the stomach were examined simultaneously by a modified method of intestinal perfusion and aspiration. After simple SPV initially a marked decrease of gastric volume and normal emptying into the duodenum were found. With additional pyloric stenosis no significant change was found. The pyloroplasty lead to an increase of gastric volume and delayed emptying. The acid secretion after feeding reduced by SPV was not changed significantly neither by pyloroplasty nor by pyloric stenosis. The baseline values of serum gastrin were elevated after SPV as well as after SPV in combination with pyloric stenosis or pyloroplasty. After food stimulation there was a delayed increase of gastrin after SPV which differed from that after SPV with pyloric stenosis or pyloroplasty only during the first hour. These results show that after SPV no further improvement of the motoric and secretory function can be achieved by an additional pyloroplasty. Furthermore these findings permit the conclusion that even after SPV with additional artificial pyloric stenosis no delayed gastric emptying occurs and that there is no negative effect postoperatively on the acid secretion and gastrin production.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    European archives of oto-rhino-laryngology and head & neck 210 (1975), S. 272-273 
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary More than 40 patients with malignant tumors of head and neck were investigated on cytostatic therapy. In these patients advances tumor stage was manifested. Therefore a major curative effect of therapy was not expected. In the beginning of cytostatis surgical and radiological possibilities were exhausted. Theoretical basis of the performed therapy were animal experiments of H. O. Klein in which evidence of cell cinetics for cytostatic therapy was demonstrated. The tumorcell cycle was determined autoradiographically with the double labeling method (H3- and C14-Thymidine) in vitro in most of the patients. A slow proliferation rate of tumor cells regularly was found. So a high dose oytostatic treatment (high dose monodrug therapy) appeared not to be optimal. Therefore we prefered in our cases a combination therapy with Cyclophosphamide (2–3 mg/kg body weight/day) and Methotrexate® (2.5–5 mg/day). Methotrexate® was given on only 3 days of the week to avoid severe haematological complications. In other cases without these complications the substance was administered dayly. In drug incompatibility other oytostatic substances were used. In most of the patients tumor development could be retarded, stopped, or a regression could be induced. Only in some cases no effect was observed. Details of cytostatic therapy, evaluation of toxic side effects and complications, also time and success of therapy are demonstrated in diapositives.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 14 (2000), S. 371-376 
    ISSN: 1434-6036
    Keywords: PACS. 61.16.Ch Scanning probe microscopy: scanning tunnelling, atomic force, scanning optical, magnetic force, etc. - 68.35.Bs Surface structure and topography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: We report here a preparation for thin gold films on mica substrates. We have investigated the influence of the substrate temperature and the evaporation rate on the morphology of the films. After careful outgasing of the substrate, 100 nm of Au is evaporated onto the mica surface maintained at high temperature. After slow cooling, ex situ characterizations are performed using AFM and STM. For our purposes, the best compromise between roughness and grain size is found to occur for an evaporation rate of 2 Ås-1 onto a mica substrate maintained at 460 C. We have used these substrates for STM and AFM study of decanethiol self-assembled monolayers (SAMs). We present results for gold samples immersed for a few seconds in decanethiol solutions, revealing an incomplete organization of the films. The organization process is discussed through comparison between AFM and STM data recorded on the SAMs. Then we present molecular resolution STM pictures of ordered SAMs for longer immersion times.
    Type of Medium: Electronic Resource
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