ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Artikel  (135)
  • Elektrotechnik, Elektronik, Nachrichtentechnik  (135)
Sammlung
  • Artikel  (135)
Datenquelle
Schlagwörter
Verlag/Herausgeber
Erscheinungszeitraum
Zeitschrift
Thema
  • 1
    Digitale Medien
    Digitale Medien
    A laser-aided prealigned pinhole collimator for synchrotron x rays (1994)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 597-602 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A pinhole small-angle x-ray scattering (SAXS) instrument was constructed at the SUNY X3A2 beamline, National Synchrotron Light Source, Brookhaven National Laboratory. The three pinholes were mounted in a thick-walled stainless steel pipe and prealigned by using a portable laser source and a charge-coupled device (CCD) area detector. After the prealignment, incorporation of the collimator to the synchrotron x-ray source required only maximization of the incident x-ray intensity passing through the pinholes, which could be done easily by using a scintillation counter after proper attenuation. The entire synchrotron SAXS instrument setup took only a few hours even without stepping motor control for the pinhole collimator unit. By combining this collimator with a CCD-based x-ray area detector which could be assembled by using commercially available components, the SAXS instrument showed good performance for structural scales up to an order of 100 nm. The CCD-based x-ray area detector used a computer- (or manually) controlled intensified unit with a variable gain setting in order to accommodate the changing x-ray flux and to protect the detector from over exposure, a necessary feature for operation of an area detector at a synchrotron light source.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1145123
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Installation and operation of the LNLS double-crystal monochromator at CAMD : Proceedings of the 5th international conference on synchrotron radiation instrumentation (1995)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 66 (1995), S. 2214-2216 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A new x-ray beamline has been installed at CAMD utilizing a two-crystal monochromator designed and built at LNLS. The beamline will operate in the 2–18 keV range using up to 4 mrad of dipole radiation from the CAMD storage ring. The monochromator maintains a fixed exit beam and fixed positions of the beam on the two crystals using mutually perpendicular elastic translations. With the ring operating at 1.5 GeV and 160 mA, Si(220) crystals will provide a flux of ∼3(109) photons/s/mrad at 8 keV, with an energy resolution ΔE〈2 eV, to the experimental hutch. The beamline is equipped with an EXAFS endstation and will also be used for other x-ray applications at CAMD. First results are presented. © 1995 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1145710
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    A high-temperature Bonse–Hart ultrasmall-angle x-ray scattering instrument (1993)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 1510-1514 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A Bonse–Hart ultrasmall-angle x-ray scattering (USAXS) instrument has been designed, constructed, and tested employing a synchrotron x-ray source. The instrument permits experiments ranging from below 0 °C up to about 400 °C, as well as temperature scanning, jumping, quenching, and annealing experiments. The mechanical elements used Super Invar as the basic building material in order to minimize the thermal expansion effect. As the synchrotron beam after the beamline optics is already somewhat collimated and monochromatized, a very fine tuning of the first crystal was necessary. The high-temperature Bonse–Hart instrument increased the performance by a factor of about 10 when compared with our earlier room-temperature Bonse–Hart instrument using the same set of channel-cut germanium crystals. The instrument was tested by using a suspension of polystyrene latex spheres and by combining the USAXS measurement, for the first time, with measurements of the same latex suspension by means of laser light scattering.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1144465
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Characterization of two resistive anode encoder position sensitive detectors for use in ion microscopy (1993)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 420-429 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Both the standard resistive anode encoder (RAE) position sensitive ion detector and a new faster version have been adapted for use with CAMECA IMS-3f/4f imaging secondary-ion mass spectroscopy instruments. Each detector includes a dual microchannel plate image intensifier mounted in front of a resistive anode. The conversion efficiencies of the standard and fast detectors are 60% and 55%, respectively. The high count rates attainable with the fast detector require high strip-current microchannel plates for optimum performance. The mass bias of these detectors is proportional to (mass)1/2 and can be compensated by adjustment of detector supply voltage. The response across the active area of these detectors is uniform to within 3% with the greatest deviations occurring at the periphery. Distortion and pixel-to-pixel bias are negligible with the standard RAE, but noticeable in the prototype of the fast RAE. Software has been developed that corrects pixel-to-pixel bias. The dead times of the standard and fast RAE systems are 4.3±0.1 μs and 330±2 ns which limit practical count rates to about 40 000 and 600 000 Hz, respectively. For many applications, the higher ion arrival rates and dynamic range of the fast RAE imaging system more than compensate for the increased pixel-to-pixel bias and distortion and the small decrease in conversion efficiency.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1144211
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Noncontact measurement of étalon spacing using a retroreflection technique (1999)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 70 (1999), S. 2225-2229 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A novel technique is described for the noncontact determination of the spacings of solid and air-gap étalons of low reflectivity by the retroreflection of a He–Ne laser beam. Gaps as small as 50 μm were measured with a precision of better than ±1 μm. Typical measurement accuracy is better than 2%. © 1999 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1149741
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    Construction of a high-energy Bonse–Hart ultrasmall-angle x-ray scattering instrument (1994)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 3233-3237 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A Bonse–Hart ultrasmall-angle x-ray scattering (USAXS) instrument, employing a synchrotron x-ray source at an energy of 18.86 keV (wavelength λ=0.06573 nm), has been designed, constructed, and tested. Solid as well as suspensions of polystyrene and poly(chlorostyrene) latex spheres were used as reference standards in order to demonstrate the range of this instrument. The USAXS results measured at λ=0.06573 nm were also compared with those from a calibrated Bonse-Hart instrument operating at λ=0.154 nm, i.e., the standard Cu Kα radiation. The higher-energy synchrotron x rays permit us to study absorbing and/or opaque materials having long range inhomogeneities in the order of microns. Furthermore, for many polymer systems, the optimal sample thickness at λ(approximately-equal-to)0.066 nm is increased to ∼10 mm and thin-walled glass windows become acceptable. Thus, a cylindrical light-scattering cell with a wall thickness of 0.3 mm could be used for both USAXS and laser light scattering measurements. The main hurdle for performing simultaneous static and dynamic light scattering as well as USAXS experiments on polymer solutions and gels with the same sample has been resolved. This capability should open up new frontiers in structural and dynamical studies of systems involving a large range of length scales from angstroms to microns.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1144556
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    High-current-density metal-ion implantation : Proceedings of the fourth International Conference on Ion Sources (1992)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 63 (1992), S. 2491-2493 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Design features and preliminary performance data for an ion-implantation system that derives its broad, high-current-density beam directly from a steady, metal-plasma discharge in a high temperature graphite chamber are described. Metal vapor is supplied by drawing electron current to an anode-potential crucible to vaporize a pure metal in it. Argon used to start the discharge is turned off once sufficient metal vapor is present to sustain it. Extraction of metal-ion beams that are several centimeters in diameter at current densities ranging to several hundred μA/cm2 of titanium or copper onto targets 50 cm from the ion source is demonstrated. The system is simple, reliable, and easy to maintain.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1142922
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Modification of a Princeton Applied Research FM-1 vibrating sample magnetometer (1991)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 62 (1991), S. 779-783 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A Princeton Applied Research model FM-1 vibrating sample magnetometer (VSM) has been modified using lock-in detection, automatic data acquisition, and microcomputer control. The practical sensitivity in the updated version has been improved to 10−4 emu. Data collection and data management are quicker and greatly simplified. Through menu driven software and modular design, the overall ease of use has been enhanced. The original layout of the FM-1 has been retained so that no versatility is lost for either the original or modified version.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1142084
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Reuse Pattern for Microcellular Networks (1999)
    Springer
    International journal of wireless information networks 6 (1999), S. 1-7 
    Details
    ISSN: 1572-8129
    Schlagwort(e): REUSE PATTERN ; MICROCELL ; MICROCELLULAR SYSTEM ; MICROCELLULAR REUSE PATTERN ; HIERARCHICAL CELL STRUCTURE
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Abstract This paper proposes novel reuse patterns formicrocellular networks based on a square grid. Aninitial carrier-to-interference ratio assessment forthese patterns considers the mobiles positioned at the worst-case condition and the system operatingat a full load. Among the possible reuse patterns (1, 2,4, 5, 8, 9, 10, 13, . . . microcells per cluster) theperformance analysis investigates systems with clusters of 5, 8, 9, and 10 microcells. Theresults show a substantial difference in performance forthe up- and downlinks, with the former performing lesssatisfactorily than the latter, and with this difference diminishing as the size of thecluster increases. Both the 10- and the 9-microcellclusters exhibit an outstanding performance and, ifappropriately explored, a remarkable trade-off betweencapacity and interference may be encountered in the5-microcell cluster.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1018814931463
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    Reminder on queueing theory for ATM networks (1996)
    Springer
    Telecommunication systems 5 (1996), S. 1-24 
    Details
    ISSN: 1572-9451
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Abstract Queueing theory is a very useful means for performance prediction during the system design phase, for resource dimensioning and for planning of networks according to load andquality of service figures. In this paper, an overview is given about traffic models for ATM traffic sources, generic ATM traffic control models and performance evaluation methods.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02109724
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...