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
Filter
  • 1990-1994  (21)
  • 1980-1984  (10)
Material
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 546-551 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Atomic force and scanning tunneling microscopy images of nanophase palladium and silver materials taken on various length scales are presented. The samples show a conformational packing of individual nanometer-sized clusters. In the case of silver, islands of clusters are observed on micrometer length scales. The islands are very flat and separated by deep crevices. The grains (clusters) within the islands are closely packed with shapes adjusting to the neighboring grains. The islands are compact, either equiaxed or oblong in shape. Average island diameters of 200–300 nm and average grain sizes of 20–50 nm were measured. The height variations on the islands are between 5 and 15 nm. The crevices are between 200 and 400 nm deep. In the case of palladium, the clusters are more uniformly packed and do not appear to be agglomerated in islands. Palladium grain sizes typically of 15 nm were measured along with corrugations of 10 nm in the closely packed areas.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Archives of orthopaedic and trauma surgery 96 (1980), S. 247-258 
    ISSN: 1434-3916
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Wir berichten hier über die Nachuntersuchungsergebnisse an 881 operierten Hüftgelenken, die im Zeitraum 1968 bis 1975 an der Orthopddischen Universitätsklinik implantiert wurden. Durch genaue Recherchen konnten 75% aller Patienten im Laufe des Jahres 1978 klinisch nachuntersucht wurden, über den Rest wurden alle erhdltlichen Informationen gesammelt. An dem Patientengut mit einem Durchschnittsalter von 62,5 Jahren wurde vor allem die postoperative Beweglichkeit im Verlauf der Jahre untersucht. Auch die funktionelle Aktivität, subjektives Patientenurteil, Schmerzen, Arbeitsfähigkeit und Wetterfühligkeit wurden analysiert. Es zeigten sich nach drei- bis zehnjähriger Implantationszeit der Hüftprothesen ermutigende Ergebnisse. Auch 9,8% aseptische Prothesenlockerungen wurden hinsichtlich ihrer Ursachen untersucht. Die Infektionsrate liegt mit 0,56% sehr nieder, auch periartikuldre Verkalkungen traten nur in einem vergleichsweise kleinem Prozentsatz auf (13,5%). Sonstige Komplikationen zählten wir bei 6,8% der Patienten. Insgesamt boten 74% der operierten Patienten ein sehr gutes oder gutes Gesamtergebnis.
    Notes: Summary We report on the follow-up examination results of 881 operated hip joints which were implanted in the Innsbruck University Clinic for Orthopedics during the period 1968–1975. Due to exact checking 75% of all patients could be clinically control-examined during 1978 and all available information regarding the others was collected. In the patient group with an average age of 62.5 years the course of postoperative mobility over the years was mainly examined. Functional activity, subjective patient opinion, pain, work capability and weather sensitivity were also analyzed. After an implantation period of the hip prosthesis of 3–10 years encouraging results were shown. Aseptic prostheses loosenings (9.8%) were examined with regard to their causes. The infection rate was very low at 0.56% and also periarticular calcification only occurred comparatively seldom (13.5%). Other complications were recorded in 6.8% of the patients. In total, 74% of the operated patients offered a very good or good complete result.
    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.] : Nature Publishing Group
    Nature 347 (1990), S. 419-419 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] SIR-The crisis at London's Natural His-tory Museum, which erupted when the corporate plan was announced on 23 April this year, has now lasted more than four months and shows no sign of ending. The essence of this crisis is that the plan will result, whatever its stated intentions, in narrowing the ...
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 53 (1983), S. 71-74 
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Mass spectra of N2O-clusters in the size rangen≲7,000 molecules per cluster, formed in a supersonic beam, have been recorded in a time-of-flight mass spectrometer. The spectra trace the transition from growth by successive monomer addition to growth by cluster coagulation. The influence of the ionization process and the detection probability is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 26 (1993), S. 311-313 
    ISSN: 1434-6079
    Keywords: 36.40.+d ; 35.20.Wg
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Using a pulsed CO2 laser we have desorbed C60 clusters from a solid target into an expanding He jet, coupled to a time-of-flight mass spectrometer. We observed self ionization of the excited clusters with a time delay of 120 ±20 µs. This is large compared to previously reported delays of up to 15 µs after laser excitation with visible or ultraviolet light. We suggest that the delayed ionization is caused by structural isomers of hot C60 clusters differing from the truncated-icosahedron structure.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of low temperature physics 93 (1993), S. 85-100 
    ISSN: 1573-7357
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A charged magnetic microsphere (radius 100 µm) is levitating inside a superconducting niobium capacitor. Because of its charge of about 1 pC, oscillations about the equilibrium position can be excited and detected electrically. The properties of this oscillator are investigated in order to study the static and dynamic forces of magnetic levitation. We find resonance frequencies between 200 Hz and 600 Hz. The resonance frequency and the damping are amplitude dependent due to nonlinear return forces and nonlinear friction, respectively. At small amplitudes the Q value is about 106 in vacuum. A dc field can be applied to change the equilibrium position and consequently the resonance frequency. From the data the spatial dependence of the static force and of the dynamic stiffness can be determined and an empirical relation between both is established. Quite often, we find a hysteretic behavior of the static force whereas the stiffness is a reversible function of the position. Amplitude dependent damping is observed both in the decay of the free oscillations and in the dependence of the amplitude of the forced oscillations on the driving force.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1434-6079
    Keywords: 36.40 + d ; 61.16.Di
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We report a topographic study of platinum clusters on highly-oriented pyrolytic graphite (HOPG) using a scanning tunneling microscope operating in air. The particles were produced by evaporation of platinum onto the graphite-surface in high vacuum. The simultaneous finding of single platinum atoms, clusters and small particles on an otherwise clean and atomically flat surface shows that the platinum-HOPG surface interaction is strong enough to yield stable images of Pt atoms and yet is not strong enough to annihilate the Pt-Pt interaction. Small flat platinum clusters on HOPG can be imaged with atomic resolution of the cluster and the surrounding graphite lattice. We show the adsorption site distribution for the monomers. The Pt-dimers show a very broad bond length distribution on graphite with an average of 2.46 Å. We found two types of Pt-trimers, one which is almost linear and one of triangular form. The average nearest neighbour distance of the trimers is 2.61 Å.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 26 (1993), S. 314-316 
    ISSN: 1434-6079
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We have used gold-, tungsten-, and copper plates to contact repeatedly a C60 powder sample. We observed the flow of electrons to the sample leading to negative charge accumulation. In repeated-contact experiments, we find charge saturation after 15 contacts for gold and copper contact partners. This is typical for the behavior of a semiconductor. For contact with tungsten however, charge accumulation continues even after 30 contacts. This unusual behavior is explained by the electron state density distribution of C60.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 19 (1991), S. 323-325 
    ISSN: 1434-6079
    Keywords: 36.40. + d ; 61.16.Di
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The scanning tunneling microscope is an ideal tool to study the local geometric and electronic structure of single supported metal clusters. Our experimental setup consists of an extraction type ion gun combined with a quadrupol mass spectrometer to deposit mass-selected metal cluster. ions. First results showing scanning tunneling microscopy pictures of sputtered aluminum clusters are presented.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 19 (1991), S. 287-292 
    ISSN: 1434-6079
    Keywords: 36.40 + d ; 73.40 Gk
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Scanning tunneling microscopy (STM) and spectroscopy (STS) are new methods to investigate atomic arrangements and electronic structures of clusters and small particles of atoms. In this paper we review recent developments in this field, in particular the work from our laboratory. We show studies of single adatoms, small clusters and larger particles of platinum and a trimer of aluminum imaged with atomic resolution on highly-orient ed pyrolytic graphite. We find different isomeric structures for clusters of a specific size. Taking the substrate lattice as reference we determine bond lengths and angles for the clusters. We find that adsorbed Pt-particles have a strong influence on the substrate. Periodic charge density modulations on the graphite lattice surrounding the particles are observed. We also discuss recent STS experiments which showed Coulomb blockade in electron tunneling. A silicon-oxide-graphite tip-junction is used where a mesoscopic insulating area containing trap levels for temporary electron storage is responsible for the blockade of single electron transport. Such an ultra-small insulator capacitor shows large voltage steps in current-voltage characteristics and quantization of the tunneling current.
    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...