ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 2000-2004  (63)
  • 1970-1974  (40)
  • 1
    Electronic Resource
    Electronic Resource
    The Frankfurt 200 mA proton source : The 8th international conference on ion sources (2000)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 71 (2000), S. 836-838 
    Details
    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
    URL: http://dx.doi.org/10.1063/1.1150307
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Measurement of the beam emittance of the Frankfurt proton source : Papers from the Ninth International Conference on Ion Sources (2002)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 73 (2002), S. 1027-1029 
    Details
    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
    URL: http://dx.doi.org/10.1063/1.1431418
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Experimental determination of the instrumental transparency function of texture goniometers (2000)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 33 (2000), S. 1162-1174 
    Details
    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
    URL: http://dx.doi.org/10.1107/S0021889800007251
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Circannuale Periodik bei Grasmücken (Sylvia) (1971)
    Springer
    Cellular and molecular life sciences 27 (1971), S. 399-399 
    Details
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary InSylvia borin andS. atricapilla, circannual rhythmicity was found in moult, migratory restlessness and in changes of body weight and gonad size under constant photoperiodic conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02137272
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Release Factors mediating Termination of Complete Proteins (1970)
    [s.l.] : Nature Publishing Group
    Nature 226 (1970), S. 1029-1033 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] In vitro studies using antisera to each of the two E. coli release factors, R1 and R2, show that these factors mediate release of complete proteins. Either factor can terminate R17 coat protein or R17 RNA ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/2261029a0
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Genetically controlled chromosome breakage and reunions in the meiosis (1972)
    Springer
    Chromosoma 37 (1972), S. 223-231 
    Details
    ISSN: 1432-0886
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Three mutants of Pisum sativum showing anomalies in the conjugation phase of meiosis, were investigated cytogenetically. Inspite of apparent normal chromosome pairing there is a strong reduction of chiasma number resulting into univalent formation. Simultaneously, chromosome aberrations appear as consequence of breakage and reunions in the prophase stage. The combined occurrence of these anomalies and their respective quantitative relationships to each other have been explained in the light of “breakage-reunion hypothesis” through the action of following factors: pairing behaviour, breakage frequency, number of breakages at one locus in the chromatid tetrads, behaviour of breakage ends and effects of environment. Due to the interaction of these factors all the anomalies found in our mutants are explainable.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00284941
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Erratum (1970)
    Springer
    Histochemistry and cell biology 22 (1970), S. 84-84 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00310556
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    In vitro-Verfahren zur autoradiographischen Bestimmung der Zellkinetik der Erythroblasten bei Tier und Mensch (1970)
    Springer
    Histochemistry and cell biology 21 (1970), S. 369-381 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung In der vorliegenden Arbeit wird ein Verfahren zur autoradiographischen Bestimmung des Zellzyklus der Erythroblasten in vitro angegeben. Die Knochenmarkzellen wurden bei +37°C in autologem oder homologem Plasma, das H3- bzw. C14-Thymidin enthielt, bei verschiedenen O2-Drücken inkubiert. Zur Bestimmung der DNS-Synthesezeit wurde das Doppelmarkierungsverfahren und zur Bestimmung der G2-Phase das „%-markierte-Mitosen-Verfahren” angewandt. Vergleichende in vivo- und in vitro-Messungen zeigten, daß bei 2,2 atü reinen O2 bei der hier angewandten in vitro-Methode das Wachstumsverhalten der Erythroblasten beim Tier und offenbar auch beim Menschen den in vivo gefundenen Werten entspricht.
    Notes: Summary This paper describes an in-vitro-method for the autoradiographical determination of the cell cycle of erythroblasts (rat, mouse, and man). The bone marrow cells were incubated (37° C) for two hours in autologous or homologous plasma containing H3- and C14-thymidine respectively. For determination of DNA synthesis time the double labeling technique, for estimation of the premitotic G2-phase the method of labeled mitoses was applied. The comparison of in vivo and in vitro measurements shows that using 2,2 atm of pure oxygen by the described in-vitro-method the cell proliferation kinetics of erythroblasts of rat, mouse, and man were approximately the same as in vivo.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00280906
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Experiments concerning the cancellation theory of visual direction constancy (1970)
    Springer
    Naturwissenschaften 57 (1970), S. 456-456 
    Details
    ISSN: 1432-1904
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00607742
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    New states and -transitions in Bi observed in the (He,d )-subcoulomb-reaction (2000)
    Springer
    The European physical journal 8 (2000), S. 157-160 
    Details
    ISSN: 1434-601X
    Keywords: PACS 21.10.Pc Single-particle levels and strength function – 23.20.Lv Gamma transitions and level energies – 25.55.-e 3H-, 3He-, and 4He-induced reactions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: Single-particle states as well as collective states in the natural Bismuth isotope 209Bi were investigated using two EUROBALL CLUSTER detectors at the Cologne FN-tandem accelerator. The states were populated by the subcoulomb proton stripping reaction 208Pb He,d 209Bi at 20.5 MeV beam-energy. Forty-eight -transitions and 33 levels were observed for the first time. Gamma-transitions up to an energy of 6.0 MeV were detected. The energy of the observed states were determined to an accuracy of about 0.3 keV.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100530050021
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...