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
  • 2005-2009  (175)
  • 1985-1989  (65)
  • 1955-1959  (15)
Collection
Years
Year
  • 1
    facet.materialart.
    Unknown
    PANGAEA
    In:  Supplement to: Meyer, M A; Huang, G-H; Morris, G J; Friedmann, E Imre (1988): 2.2 The effect of low temperatures on Antarctic endolithic green algae. Polarforschung, 58(2/3), 113-119, hdl:10013/epic.29606.d001
    Publication Date: 2023-07-10
    Description: Laboratory experiments show that undercooling to about -5°C occurs in colonized Beacon sandstones of the Ross Desert, Antarctica. High-frequency temperature oscillations between 5°C and -5°C or -10°C (which occur in nature on the rock surface) did not damage Hemichloris antarctica. In a cryomicroscope, H. antarctica appeared to be undamaged after slow or rapid cooling to -50°C. l4CO2 incorporation after freezing to -20°C was unaffected in H. antarctica or in Trebouxia sp. but slightly depressed in Stichococcus sp. (isolated from a less extreme Antarctic habitat). These results suggest that the freezing regime in the Antarctic desert is not injurious to endolithic algae. It is likely that the freezing-point depression inside the rock makes available liquid water for metabolic activity at subzero temperatures. Freezing may occur more frequently on the rock surface and contribute to the abiotic nature of the surface.
    Keywords: Age; Cycles; Range; Standard deviation; Viability
    Type: Dataset
    Format: text/tab-separated-values, 112 data points
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 89 (1988), S. 1067-1073 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Molecular dynamics method and Lennard-Jones potential functions are employed to model liquid–liquid interfaces. The simulations are carried out in a range of temperature and pressure near the triple point. The investigated systems are symmetric and composed of two identical liquids L1 and L2. The interactions between the atoms of L1 and L2 are obtained from modified Lennard-Jones potential functions where extra parameters are introduced to reduce the miscibility between the two liquids. The interfacial tensions and the miscibilities are varied by using different parameters. The interfaces thus obtained are stable on the time scale of the simulation as shown by the density and pressure profiles. This is also confirmed by a geometrical analysis performed in order to characterize the fluctuations of the interfaces. The calculation of the diffusion coefficients shows clearly an anisotropy of the diffusion process in the interfacial region.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 53 (1988), S. 1335-1337 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Fine line superconductors of Y-Ba-Cu-O were formed on 〈100〉 SrTiO3 by the completely nonvacuum techniques of metalorganic deposition and selective laser pyrolysis. Lines 35 μm wide were written, using an Ar laser, in metal neodecanoates prior to pyrolysis. Regions of the metalorganics not exposed to laser pyrolysis were developed away using a xylene wash. Complete pyrolysis of the metal neodecanoates and rapid thermal annealing produced lines having superconducting onsets above 90 K and zero resistance at 69 K.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of the American Chemical Society 77 (1955), S. 3482-3484 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 62 (1958), S. 827-829 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 63 (1959), S. 1519-1521 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 63 (1959), S. 1325-1326 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of the American Chemical Society 79 (1957), S. 3659-3661 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Polar biology 8 (1988), S. 225-233 
    ISSN: 1432-2056
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Standardized abundances of 40 frequently occurring macrozooplankton taxa collected by double-oblique bongo net hauls between the surface and 200 m depth were submitted to an agglomerative hierarchical cluster analysis, to characterize surface zooplankton communities in the southern and eastern Weddell Sea. The sensitivity of the analysis concerning reduction of the number of considered taxa (especially stages of species) was tested. Dominant taxa in the entire area over the whole period were copepods Metridia gerlachei and Calanoides acutus. Calanus propinquus, Appendicularia spp. and calyptopis-1 larvae of krill, Euphausia superba were abundant at 73°S/19°W. Euphausia crystallorophias and larval fish Pleuragramma antarcticum dominated at 77°S/40°W on the southern shelf. The cluster analysis revealed marked similarities between the southern shelf community and the January community further to the northeast. E. crystallorophias, and larval Pleuragramma antarcticum are thought to be transported in surface layers of the coastal current to the southwest. Oceanic species such as Thysanoessa sp. and E. superba are probably not transported in the same way. Possible mechanisms for the maintenance of the community structures are discussed. A simplified method of characterizing communities, based on analysis of euphausiids, is presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Polar biology 9 (1989), S. 415-422 
    ISSN: 1432-2056
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Schistidium antarctici is the commonest of five bryophytes known in the Windmill Islands area of Wilkes Land, Greater Antarctica. In moist habitats it forms closed carpets, but in dry sites it develops a short cushion growth form. Carbon dioxide exchange of both a mesic (Sm) and a xeric growth form (Sx) was investigated by means of an IRGA system in the field near Casey Station under natural light and simulated ambient or controlled temperature conditions in the plant chamber. The chlorophyll content in Sm was three times higher than in Sx. The light compensation point of Sm was lower than in Sx. The data for photosynthesis and dark respiration were computed by means of non-linear and linear regression analysis. Sm was more productive and had a wider temperature range of positive net photosynthesis than Sx under similar conditions. Dark respiration per gram of the whole moss sample was identical in both ecodemes. A decline of the photosynthesis curves at quantum flux densities above 500 μmol m-2 s-1 PAR indicated a photoinhibitory effect in Sm. Sx was even more sensitive to high irradiance levels. Photoinhibition was not apparent in laboratory measurements under artificial light. According to our field measurements the photoinhibitory effect increases with increasing temperature. Moisture loss was avoided during the experiments by water supply from the bottom and frequently spraying the moss samples with water. In the natural habitat the desiccating effect of solar radiation is important, as it quickly causes photosynthesis to cease. The moss will dry out sooner in a xeric habitat than in one which is continuously moist. Consequently, the mesic Schistidium might particularly be subjected to photoinhibition by bright sunshine.
    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...