Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 67 (1996), S. 1054-1056 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A volume source, based on the high efficiency ion source (HIEFS), is being developed for D+ production in steady state operation. The source will be optimized for the extraction of atomic deuterium ions with high current densities. It was found that a maximum deuterium ion beam current density of 210 mA/cm2 can be achieved with a D+ fraction above 90%. At an extraction voltage of 35 kV and with an aperture radius of 4 mm, the source delivers 61 mA D+. After a description of the source and the experimental setup, the results of detailed studies of the beam composition in dependence of the plasma parameters are presented. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 1012-1014 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: For the European spallation source, a volume source based on the high efficiency source is being developed. The source will be optimized to produce high current densities in pulsed operation. A pulse generator delivering 1–1.5 ms pulses was installed. Furthermore, cesium was supplied to the plasma generator from an external oven. The cesium injection was optimized for a low e/H− ratio and a high current. We obtained a current density of 70 mA/cm2. This way, with an aperture radius of 4.25 mm, an H− current of 40 mA was extracted at an extraction voltage of 22 kV. After a description of the source and the experimental setup, measurements of the beam current density and the e/H− ratio will be presented in this article. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 67 (1996), S. 1039-1041 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A new version of the high efficiency source is being developed for the European Spallation Source. The goal of these experiments is to produce a nearly pure H− ion beam with a low electron to H− ratio and high current (70 mA). To achieve this, the discharge chamber is divided into two parts of different plasma parameters by means of a filter magnetic field. Furthermore, the plasma chamber is aligned unsymmetrically with respect to the z axis of the extractor. We obtained a current density of 10 mA/cm2 for an arc power as small as 1 kW. In preliminary experiments, a beam of 10 mA was extracted at an extraction voltage of 8 kV (1.8% impurities). Measurements of the beam current density, electron to H− ratio, and the ion composition for a wide range of discharge conditions will be presented in this article. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 1066-1068 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A volume source based on the high efficiency source is being developed for heavy ion production. Bismuth was chosen for exemplifying investigations because of its low melting point. The ion source is driven by an arc discharge ionizing bismuth atoms which are evaporated from an oven inside the source chamber. It has been optimized to produce a beam with a fraction of singly ionized bismuth above 92%. A multiaperture extraction system was built consisting of seven holes with a radius of 3 mm each. For that system, the perveance limit was achieved at a beam current of 70 mA and an extraction voltage of 27.5 kV. The corresponding emission current density amounts to 35 mA/cm2. This value was obtained for an arc power of only 280 W. Furthermore, the emittance of a beam extracted from the multiaperture extraction system has been determined with a high power emittance scanner. It amounts to 0.27π mm mrad (80%, normalized, 4 rms). In this case, the emittance of a single beam is 0.017π mm mrad. This article will give a detailed description of both the source and the experimental setup. In addition, various dependencies between the plasma parameters and the beam composition are presented. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 68 (1997), S. 2698-2706 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Among the various possibilities for investigating the properties of ion beams, two of the most important principles for determining the beam quality are profile measurements using wires or slit apertures, and different kinds of emittance measurement devices. However, most of the commonly used systems have the disadvantage of being either destructive to the beam, or at least to have a considerable influence on the further beam propagation downstream of the point of measurement. Also, for the investigation of intense ion beams, thermal problems on the scanners themselves might arise. Observation of particles emitted from the ion beam in radial direction allow an indirect but nondestructive observation of the beam. Of the different optical methods that exist to accomplish this, we recently conducted an investigation on the possibilities to employ a charge coupled device-camera system for such nondestructive beam diagnostics in our space-charge compensation test stand. First, experimental results on optical profile measurements are presented and compared to results obtained by a slit scanner and a wire scanner. Additionally, to gain a better understanding of the measured data, optically obtained sectional profiles behind a slit and a circular aperture were analyzed. Possibilities for gaining information on the two-dimensional beam profile and the beam emittance are explored. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Analytical chemistry 31 (1959), S. 579-581 
    ISSN: 1520-6882
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Macromolecules 28 (1995), S. 1003-1007 
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    facet.materialart.
    Unknown
    Manchester : Periodicals Archive Online (PAO)
    Journal of Semitic studies. 3:2 (1958:Apr.) 169-221 
    ISSN: 0022-4480
    Topics: Linguistics and Literary Studies , Ethnic Sciences
    Notes: REVIEWS
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    Manchester : Periodicals Archive Online (PAO)
    Journal of Semitic studies. 3:4 (1958:Oct.) 363 
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 353 (1971), S. 333-346 
    ISSN: 1432-2307
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die feinstrukturelle Untersuchung von 7 Basalzelladenomen der Glandula parotis ergibt, daß diese gutartigen Speicheldrüsentumoren aus epithelial differenzierten Zellen aufgebaut sind. Die Geschwulstzellen enthalten außer einem spärlichen Inventar von Zellorganellen zahlreiche ungeordnet verlaufende feine Fibrillen, wie sie auch in anderen Tumoren der Speicheldrüsen und der Brustdrüse vorkommen. Herkunft und Funktion dieser Fasern sind nicht bekannt. Die epithelial differenzierten Geschwulstzellen wirken offensichtlich mit an der Bildung von interstitiellen Fibrillen und basalmembranartiger Substanz, wobei in einzelnen Basalzelladenomen der Eindruck einer ödematösen Durchtränkung des Geschwulststromas entsteht. Eine Besonderheit der Basalzelladenome stellt darüber hinaus das Vorkommen von Elastica-Material zwischen den Geschwulstepithelien dar. Da in den Basalzelladenomen Myoepithelzellen am Geschwulstaufbau nicht beteiligt sind, können sie von den Myoepithel führenden Speicheldrüsentumoren, wie Mischtumoren, Cylindromen und Speichelgangcarcinomen eindeutig abgegrenzt werden. Sie stellen eine eigenständige Geschwulstart dar und sind aufgrund der feinstrukturellen Organisation in die Gruppe der epithelialen Geschwülste der Speicheldrüsen einzuordnen.
    Notes: Summary A fine structural investigation of seven basal-cell adenomas of the parotid gland reveals their cells undergo epithelial differentiation. They contain few cell organelles and many fine filaments, a state that has also been observed in many other salivary gland tumors. The origin and function of these fibrils is not known. The cells of these epithelial tumors obviously take part in the formation of interstitial fibrils and basement membrane-like material. In some basal-cell adenomas the stroma becomes edematous. A peculiarity of these tumors is the occurrence of elastica-like material among the tumor cells. Since myoepithelial cells do not occur, the basal-cell adenoma can easily be separated from salivary gland tumors containing myoepithelial cells, i.e., from the pleomorphic adenoma (socalled mixed tumor), the adenoid-cystic carcinoma (cylindroma), and the salivary duct carcinoma. The basal-cell adenoma is a special type of salivary gland tumor and because of its fine structure has to be included with the epithelial neoplasms of the salivary glands.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...