ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
  • Articles  (16)
  • 1995-1999  (6)
  • 1990-1994  (8)
  • 1880-1889  (2)
Collection
Years
Year
  • 1
    ISSN: 1432-2145
    Keywords: Pollen-pistil interference ; Prior self-pollination ; Tristyly ; Self-incompatibility Stylar senescence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The potential inhibitory effects of incompatible pollen on outcrossed seed set were investigated in mass-flowering, self-incompatible, tristylous Pontederia sagittata. Prior application of self pollen, followed after 2, 4, or 6 h by compatible pollen, was conducted on five genotypes of each of the three style morphs under uniform glasshouse conditions. The greatest reductions in seed set occurred in pollinations of the long-styled (L) morph at the 6 h time interval. Smaller reductions were also found for this treatment in the mid-styled (M) morph. No significant reductions in seed set were observed in the short-styled (S) morph or in the other morphs at shorter time intervals. Observations of pollen germination and pollen tube growth indicated that the lack of inhibitory effects in the S morph may occur because relatively few pollen grains adhered to stigmas in selfpollinations. In the L and M morphs, early germination of self pollen may cause physical clogging of the stigma and style, resulting in a reduced number of compatible pollen tubes in styles. Observations of the structural integrity of styles indicated that prior germination of self pollen resulted in more rapid onset of pistil senescence, particularly in the L morph. These influences may contribute to the morph-specific differences in seed set observed following prior self-pollination of outcrossed flowers. The negative effects of incompatible pollen are likely to be most evident where ecological factors cause delays in the delivery of outcross pollen to stigmas.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A narrow feature recently observed in photoemission spectra of heavy rare earth metals at a binding energy of 5.5–6.2 eV has been interpreted as a many-electron satellite. We question this interpretation and suggest that this feature is due to H contamination.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Direct reaction of C60 with alkali-metal vapour in sealed pyrex tubes has been the predominant synthetic route to AXC60 (where A is K, Rb or Cs), but the lower vapour pressure and greater reactivity with pyrex are a severe problem for reactions with sodium. Therefore, we have ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 352 (1991), S. 522-524 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The experimental plant was the self-compatible annual water hyacinth, Eichhornia paniculata (Pontederiaceae). The species inhabits ephemeral pools and ditches in northeastern Brazil and the Caribbean, and exhibits a wide range of natural outcrossing rates12. The experiments reported here used ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 83 (1998), S. 480-485 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A reflectance anisotropy spectroscopy (RAS) and low-energy electron diffraction study of the InP(001) surface is presented. The surface was prepared by thermal desorption of an As-P capped epilayer grown by molecular beam epitaxy. RA spectra have been monitored over a spectral range of 1.5–5.5 eV at regular intervals during thermal decapping and annealing up to the point of decomposition (553–973 K). Each of the RA spectra of the surface reconstructions comprise positive (at 2.9 eV) and negative (at 1.8 eV) anisotropies which have been previously associated with P- and In-related bonding, respectively. Unlike other III-V (001) semiconductor surfaces, the evolution of different reconstructions cannot be explained in terms of a change in surface stoichiometry which involves loss of the anion species. In the case of InP(001) the P species contributes to the clean surface reconstruction from the early stages of decapping to the point of decomposition. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 2 (1995), S. 312-315 
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: Angle-resolved UV photoemission spectroscopy has been used to investigate the interaction of CO with Gd films, grown on W(110). The results suggest the CO absorbs dissociatively, initially forming Gd2O3, with subsequent catalytic oxidation of CO to form carbonate.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 2 (1995), S. 261-263 
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: W 4f core-level spectra of Gd films on W(110) show components which can be identified as being due to bulk and interface W. The results suggest that the W/Gd interface is abrupt, i.e. no interface alloying occurs. At submonolayer coverages a further component is seen which is attributable to intermediate (n × 2) phases.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 21 (1880), S. 537-537 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] SOMETHING very like the “comb-like masses of ice” appears upon the surfaces of plaster-models such as dentists make, after they have been coated with a preparation called Liquid Silex; except that it is finer and woolly. It seems to be caused by the contraction of the models forcing out very ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: Given the tunability of synchrotron radiation, photoemission spectroscopy can be used to monitor the growth modes of thin films in UHV. Cross-section effects such as Cooper minima and resonant photoemission can be exploited to maximize the adsorbate signal and minimize that from the substrate. Under favourable circumstances growth can be monitored in real time at coverages of 〈1%. As an example the growth of Gd on W(110) is investigated.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1573-5176
    Keywords: Isochrysis ; lipid ; mariculture ; mass culture ; microalgae ; Nannochloropsis ; nutrition ; Pavlova ; polyunsaturated fatty acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Three species of microalgae were grown in mass culture to investigate the influence of culture technique and growth phase on the production of 20:5(n−3) and 22:6(n−3). These polyunsaturated fatty acids (PUFA) are considered to be essential in many marine animals diets for high growth and survival rates. The species of microalgae examined wereNannochloropsis oculata, Pavlova lutheri andIsochrysis sp. (clone T.Iso). All batch cultures (logarithmic and stationary phase) and semi-continuous cultures (logarithmic phase) examined contained high levels of the long-chain (n−3) PUFA, but production could be maximised by harvesting at specific times and growth phases. Maximum cellular content (pg cell-1) of long-chain PUFA was found in logarithmic phase batch cultures ofN. oculata and in stationary phase cultures ofP. lutheri. The cellular content of PUFA in cultures ofIsochrysis sp. did not change significantly with culture technique or growth phase. Alternatively, stationary phase cultures of all three species showed increased proportions (%) and cellular contents of triacylglycerols, and saturated and monounsaturated fatty acids with correspondingly decreased proportions of polar lipids and most PUFA relative to logarithmic phase cultures. The exception was the proportion and cellular content of 22:6(n−3) inP. lutheri which increased with triacylglycerol content. The mass of long-chain (n−3) PUFA per volume of culture was significantly higher in stationary phase cultures due to the higher cell counts per volume. These findings indicate that the opportunity exists to maximise PUFA production by microalgae with the potential to improve animal growth and reduce production costs in mariculture operations and may be of use in the large scale culture and harvesting of microalgae for the biotechnology industry.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...