ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Physiological responses of lupin roots to high pH (1993)
    Springer
    Plant and soil 155-156 (1993), S. 509-512 
    Details
    ISSN: 1573-5036
    Keywords: Lupinus ; root elongation ; cell growth ; high pH
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract High pH seems to be a major constraint limiting the production of narrow-leafed lupin (Lupinus angustifolius L.) on alkaline soils. Whereas there has been much interest in soil acidity, relatively little is known about the effect of high pH on the growth of roots of higher plants. Elongation of roots of L. angustifolius was particularly sensitive to pH≥6.0 compared with other species. The effect of high pH in decreasing root elongation in L. angustifolius occurred within one hour. It was via an effect on cell elongation and not cell division and the effect was readily reversible. The mechanisms of the adverse effect of high pH are unknown. The permeability ratio of K+ to Na+ in the plasma-membrane of the root cortical cells was similar in solutions of both low pH and high pH. Reduced cell growth at high pH was not associated with an inefficiency of proton extrusion to the bulk solution by roots of this species. Nevertheless, increasing buffer concentration in the external solution decreased root elongation more in L. angustifolius than in Lupinus pilosus and Pisum sativum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00025095
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    High pH in the nutrient solution impairs water uptake in Lupinus angustifolius L. (1993)
    Springer
    Plant and soil 155-156 (1993), S. 517-519 
    Details
    ISSN: 1573-5036
    Keywords: water relation ; high pH ; Lupinus angustifolius
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Root growth in Lupinus angustifolius is greatly decreased when the nutrient solution has a pH above 6.0. This study examined the water relations in this species (cv. Yandee) in response to high pH in solution culture in a glasshouse. The dry weight of roots, the length of taproots and lateral roots and the number of lateral roots were significantly reduced at day 12 after transfer to solution with a pH of 7.5 compared to pH 5.2. This resulted in a marked reduction of total root surface area. However, shoot growth and total leaf area were not affected. In comparison with pH 5.2, plants grown at pH 7.5 in the nutrient solution had a 14–38% more-negative leaf water potential, and their stomatal resistance had increased by 67%. The observations indicate that the impairment of the water relations by high pH is mainly caused by decreased root growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00025097
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    facet.materialart.
    Unknown
    A three-dimensional dynamic analysis and libration study of a tethered satellites system (1986)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: By a three-dimensional Lagrangian formulation, an exact set of ten coupled nonlinear second-order differential equations has been derived for a system with an extensible tether connecting two end satellites of distributed mass. The effects of tether mass, small orbital eccentricity, central body oblateness, aerodynamic drag force, and solar radiation pressure are also included in the formulation. By linearizing the exact differential equations, the in-plane (orbital plane) differential equations are found to be decoupled from the out-of-plane ones. The characteristic equation of the in-plane differential equations is derived and some associated stability constraints are shown.
    Keywords: ASTRODYNAMICS
    Type: AAS PAPER 85-340
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    An exact solution for orbit view-periods from a station on a tri-axial ellipsoidal planet (1986)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: This paper presents the concise exact solution for predicting view-periods to be observed from a masked or unmasked tracking station on a tri-axial ellipsoidal surface. The new exact approach expresses the azimuth and elevation angles of a spacecraft in terms of the station-centered geodetic topocentric coordinates in an elegantly concise manner. A simple and efficient algorithm is developed to avoid costly repetitive computations in searching for neighborhoods near the rise and set times of each satellite orbit for each station. Only one search for each orbit is necessary for each station. Sample results indicate that the use of an assumed spherical earth instead of an 'actual' tri-axial ellipsoidal earth could introduce an error up to a few minutes in a view-period prediction for circular orbits of low or medium altitude. For an elliptical orbit of high eccentricity and long period, the maximum error could be even larger. The analytic treatment and the efficient algorithm are designed for geocentric orbits, but they should be applicable to interplanetary trajectories by an appropriate coordinates transformation at each view-period calculation. This analysis can be accomplished only by not using the classical orbital elements.
    Keywords: ASTRODYNAMICS
    Type: AIAA PAPER 86-2068
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Co-apsidal autonomous terminal rendezvous in Mars orbit (1979)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The autonomous (or unmanned) Mars Orbit Rendezvous may be divided into four phases: approach, terminal, station-keeping, and docking. The paper outlines a feasible concept for the terminal rendezvous phase. A co-apsidal terminal rendezvous technique is described which utilizes the advantages of aligning the lines of apsides of two coplanar elliptic orbits of slightly different periods but of the same apoapsis distance. An initial maneuver nulling the inclination between the orbits is followed by another maneuver to align the two lines of apsides. A proper phasing maneuver is then executed at the coapsidal point, and the final rendezvous maneuver is performed at the same coapsidal point to complete the terminal rendezvous transfer. Cases are formulated in order of complexity with a view to illustrate the basic ideas of this technique. Pertinent calculations are also presented.
    Keywords: ASTRODYNAMICS
    Type: AAS PAPER 79-167 , American Astronautical Society and American Institute of Aeronautics and Astronautics, Astrodynamics Specialist Conference; Jun 25, 1979 - Jun 27, 1979; Provincetown, MA
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    A preliminary estimate of the EUVE cumulative distribution of exposure time on the unit sphere (1984)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: A preliminary study of an all-sky coverage of the EUVE mission is given. Algorithms are provided to compute the exposure of the celestial sphere under the spinning telescopes, taking into account that during part of the exposure time the telescopes are blocked by the earth. The algorithms are used to give an estimate of exposure time at different ecliptic latitudes as a function of the angle of field of view of the telescope. Sample coverage patterns are also given for a 6-month mission.
    Keywords: ASTRODYNAMICS
    Type: AIAA PAPER 84-2017
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    Aerobraking techniques for planetary missions (1981)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: Aerobraking techniques are applied to trajectory design for the VOIR (Venus Orbiting Imaging Radar) mission to enhance overall mission performance. The approach can be used for other planetary missions such as a Titan orbiter or a Mars sample return to earth. The orientation of the elliptical insertion orbit must be chosen in such a way that the combined effects of solar gravity, central-body harmonics, and drag on periapsis altitude are minimized to avoid frequent maneuvers. The selection of the base and width of a corridor for periapsis altitude depends upon the temperature and integrated heat of the aerobrake shield, the atmospheric density profile, the duration of aerobraking, the number of maneuvers, the time available between maneuvers, and uncertainties in the central-body gravity field and atmospheric density. Flight path profiles for an aerodynamically stable spacecraft and an inertially fixed spacecraft passing through the free molecular flow regime, as well as the transitional flow regime, are illustrated
    Keywords: ASTRODYNAMICS
    Type: AAS PAPER 81-132 , Astrodynamics Specialist Conference; Aug 03, 1981 - Aug 05, 1981; Lake Tahoe, NV; US
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...