ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
Language
Number of Hits per Page
Default Sort Criterion
Default Sort Ordering
Size of Search History
Default Email Address
Default Export Format
Default Export Encoding
Facet list arrangement
Maximum number of values per filter
Auto Completion
Topics (search only within journals and journal articles that belong to one or more of the selected topics)
Show more topics
Feed Format
Maximum Number of Items per Feed
Permalink If you want to be able to use settings permanently, you must save your settings and then set a Bookmark to the permalink
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  (148)
Collection
Keywords
Publisher
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Role of copper in the green luminescence from ZnO crystals (2002)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 81 (2002), S. 622-624 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Electron paramagnetic resonance (EPR), photoluminescence, and infrared optical absorption have been used to investigate a ZnO crystal before and after a thermal anneal for 1 h in air at 900 °C. The sample was an undoped high quality crystal grown by the chemical vapor transport method. In addition to shallow donor impurities, the crystal contained trace amounts of copper ions. Prior to the thermal anneal, these ions were all in the Cu+ (3d10) state and the observed luminescence at 5 K, produced by 364 nm light, consisted of a broad structureless band peaking at 500 nm. After the high-temperature anneal, the Cu2+ (3d9) EPR spectrum was observed and the luminescence had changed significantly. The emission then peaked near 510 nm and showed structure identical to that reported by Dingle [Phys. Rev. Lett. 23, 579 (1969)]. Our data reaffirm that the structured green emission in ZnO is associated with Cu2+ ions. We suggest that the unstructured green emission (observed before the high-temperature anneal) is donor–acceptor pair recombination involving the Cu+ acceptors. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1494125
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Simultaneous micromanipulation in multiple planes using a self-reconstructing light beam (2002)
    [s.l.] : Macmillian Magazines Ltd.
    Nature 419 (2002), S. 145-147 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Optical tweezers are commonly used for manipulating microscopic particles, with applications in cell manipulation, colloid research, manipulation of micromachines and studies of the properties of light beams. Such tweezers work by the transfer of momentum from a tightly focused laser to the ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/nature01007
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Inheritance of high palmitic acid content in the sunflower mutant CAS-12 and its relationship with high oleic content (2002)
    Oxford, UK : Blackwell Publishing Ltd
    Plant breeding 121 (2002), S. 0 
    Details
    ISSN: 1439-0523
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: CAS-12 is a sunflower mutant with increased levels of palmitic (C16: 0 = 30%) and oleic (C18: 1 = 55%) acids in its seed oil, hence it has a reduced linoleic acid content (C18: 2 〈 5%). This study was conducted to determine the inheritance of high C16: 0 content and its relationship with high C18: 1 content in CAS-12. Reciprocal crosses involving CAS-12, CAS-5 (high C16: 0 content), HAOL-9 (high C18: 1 content) and HA-89 (standard fatty acid profile) were made. The F1, F2 and BC1F1 generations were obtained. The genetic control of the high C16: 0 trait in CAS-12 was partially recessive and gametophytic. In all cases, this character segregated in the ratio 19: 38: 7 (low: intermediate: high C16: 0 content) in the F2 generation. These results, together with the lack of segregation for C16: 0 content in crosses between CAS-12 and CAS-5, indicated that the genetic control of the high C16: 0 trait in CAS-12 was similar to that in CAS-5 in being controlled by partially recessive alleles (p1, p2, and p3) at three loci. Crosses between HA-89 and CAS-12, and HAOL-9 and CAS-5 (segregating for C16: 0 and C18: 1) demonstrated that the high C16: 0 and the high C18: 1 traits were independently inherited. However, C18: 1 segregation in these crosses exhibited reversal of dominance. Apparently, the low C18: 1 parental lines carried modifier genes causing the deviation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1439-0523.2002.00655.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Quaternary palaeohydrological evolution of a playa lake: Salada Mediana, central Ebro Basin, Spain (2000)
    Oxford UK : Blackwell Science Ltd
    Sedimentology 47 (2000), S. 0 
    Details
    ISSN: 1365-3091
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: Sedimentary features, mineralogy, bulk geochemical composition, stable isotope analyses and pollen data from sediment cores were used to reconstruct the Late Quaternary depositional evolution of the Salada Mediana playa lake (central Ebro Basin, northeastern Spain). The 150-cm-long sediment core sequence is composed of gypsum- and dolomite-rich muds (Lower and Middle sections) and black, laminated, calcite-bearing sediments (Upper section). The Salada Mediana formed as a karstic depression in the Miocene gypsum substratum during the Late Pleistocene. The Lower section was deposited in a sulphate–carbonate saline lake that ended with a period of desiccation and basin floor deflation. Subsequent deposition (Middle section) took place in a playa-lake system. Two cycles of lower water table and expanded saline mud flats occurred. The Holocene sequence is missing, probably as a result of aeolian erosion. Sedimentation resumed only a few centuries ago, and saline pan environments dominated until modern times. The Salada Mediana facies succession was mainly governed by fluctuations in the hydrological balance, brine composition, and salinity; however, aeolian processes (detrital input and deflation) and recycling of previously precipitated salts also played a significant role.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-3091.2000.00346.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Electron paramagnetic resonance of platinum impurities in KTiOPO4 crystals (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 87 (2000), S. 8682-8687 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Single crystals of KTiOPO4 (KTP) often contain trace amounts of isolated platinum impurities. When present in sufficient concentration, these ions increase the KTP crystal's susceptibility to form gray tracks during frequency doubling of high-power laser beams. Electron paramagnetic resonance (EPR) has been used to characterize three platinum centers in a crystal of KTiOPO4. Initially, the platinum ions are present in nonparamagnetic forms. Exposure to ionizing radiation (i.e., x rays or above-band-gap laser beams) at room temperature converts them into paramagnetic centers. Once formed, these centers are stable for weeks at room temperature; however, their EPR spectra can only be observed at temperatures near or below 30 K. An angular study provided principal values and principal directions for the g matrices and the platinum hyperfine matrices. The Pt(A) center has principal g values of 1.9397, 2.4463, and 2.5900 and is assigned to a Pt3+ ion substituting for a Ti4+ ion. In contrast, the Pt(B) center has principal g values of 1.6019, 1.9754, and 2.7788 and the Pt(C) center has values of 1.4656, 1.8597, and 2.9576. We suggest that these latter two centers are Pt+ ions substituting for K+ ions. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.373596
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Identification of electron and hole traps in KH2PO4 crystals (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 47-52 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Electron paramagnetic resonance (EPR) has been used to characterize a hole trap and several electron traps in single crystals of potassium dihydrogen phosphate (KH2PO4 or KDP). The paramagnetic charge states of these centers are produced by ionizing radiation (e.g., x rays or a 266 nm beam from a pulsed Nd:YAG laser) and are stable for days and even weeks at room temperature. One center consists of a hole trapped on an oxygen ion adjacent to a silicon impurity located on a phosphorus site. This defect has a small, but easily observed, hyperfine interaction with the adjacent substitutional proton. The other centers are formed when an electron is trapped at an oxygen vacancy. These latter defects are best described as (PO3)2− molecular ions, where the primary phosphorus nucleus is responsible for a large hyperfine splitting (500–800 G in magnitude). Five EPR spectra representing variations of these oxygen vacancy centers are observed, with the differences being attributed to the relative position of a nearby cation vacancy, either a missing proton or potassium. An angular study of the EPR spectra, conducted at room temperature, provided principal values and principal directions for the g matrices and hyperfine matrices for the hole center and two of the electron centers. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1320030
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Identification of silicon as the dominant hole trap in YVO4 crystals (2002)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 91 (2002), S. 1354-1358 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Electron paramagnetic resonance (EPR) and electron–nuclear double resonance (ENDOR) have been used to characterize the dominant hole trap in undoped Czochralski-grown yttrium–orthovanadate (YVO4) crystals. A silicon impurity, present inadvertently, replaces a vanadium ion and allows a hole to be trapped on one of the four adjacent oxygen ions. The unpaired spin resides in an oxygen p orbital oriented perpendicular to the plane defined by the silicon ion, the electron-deficient oxygen, and the two yttrium ions nearest the oxygen. Principal values of the g matrix (2.0033, 2.0090, and 2.0771) were obtained from EPR data taken at 15 K. Direct verification of the participation of silicon was obtained from ENDOR data taken at 12 K. We have found that this trapped-hole center appeared in large concentrations in all of our Czochralski-grown YVO4 crystals that were exposed to ionizing radiation (i.e., x rays or an ultraviolet laser beam) while the crystal was at 77 K. Interestingly, a small concentration of this trapped-hole center was present in some as-grown YVO4 crystals before exposure to ionizing radiation. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1428087
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Thermoluminescence study of stoichiometric LiNbO3 crystals (2002)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 92 (2002), S. 1221-1226 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thermoluminescence (TL), optical absorption, and electron paramagnetic resonance (EPR) have been used to characterize point defects in Mg-doped stoichiometric LiNbO3. A broad TL emission, peaking at 440 nm, is observed near 94 K when these crystals are irradiated at 77 K and then rapidly warmed. X rays and below-band-gap lasers (325 and 355 nm) are equally effective in producing the TL peak. During excitation, holes are trapped on oxygen ions adjacent to lithium vacancies and electrons are trapped on niobium ions at regular lattice sites. These defects both have characteristic EPR spectra, and the trapped electron center has an optical absorption band peaking at 1200 nm. Upon warming, the electrons become thermally unstable near 94 K and migrate to the trapped-hole sites where radiative recombination occurs. We suggest that the near-edge charge-transfer absorption band from Fe3+ impurities, nominally present, provides the mechanism by which below-band-gap light initially produces the separately trapped holes and electrons. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1487452
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Production of nitrogen acceptors in ZnO by thermal annealing (2002)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 80 (2002), S. 1334-1336 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Nitrogen acceptors are formed when undoped single crystals of zinc oxide (ZnO) grown by the chemical-vapor transport method are annealed in air or nitrogen atmosphere at temperatures between 600 and 900 °C. After an anneal, an induced near-edge absorption band causes the crystals to appear yellow. Also, the concentration of neutral shallow donors, as monitored by electron paramagnetic resonance (EPR), is significantly reduced. A photoinduced EPR signal due to neutral nitrogen acceptors is observed when the annealed crystals are exposed to laser light (e.g., 364, 442, 458, or 514 nm) at low temperature. The nitrogens are initially in the nonparamagnetic singly ionized state (N−) in an annealed crystal, because of the large number of shallow donors, and the light converts a portion of them to the paramagnetic neutral acceptor state (N0). © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1450041
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    MYO1, a Novel, Unconventional Myosin Gene Affects Endocytosis and Macronuclear Elongation in Tetrahymena thermophila (2000)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 47 (2000), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: . Targeted gene disruption was used to investigate the function of MYO1, an unconventional myosin gene in Tetrahymena thermophila. Phenotypic analysis of a transformed strain that lacked a functional MYO1 gene was conducted at both 20°C and 35°C. At either temperature the ΔMYO1 strain had a smaller cytoplasm/nucleus ratio than wild type. At 20°C, ΔMYO1 populations had a longer doubling time than wild type, lower saturation density, and a reduced rate of food vacuole formation. However, at 35°C, these characteristics were comparable to wild type. Although micronuclear division and cytokinesis appeared normal in ΔMYO1 cells, failure of the macro-nucleus to elongate properly resulted in unequal segregation of macronuclear DNA in cells maintained at either 20°C or 35°C.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.2000.tb00090.x
    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...