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  • 1
    Electronic Resource
    Electronic Resource
    Role of transpiration suppression by evaporation of intercepted water in improving irrigation efficiency (1995)
    Springer
    Irrigation science 16 (1995), S. 89-95 
    Details
    ISSN: 1432-1319
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Sprinkler irrigation efficiency declines when applied water intercepted by the crop foliage, or gross interception (Igross), as well as airborne droplets and ponded water at the soil surface evaporate before use by the crop. However, evaporation of applied water can also supply some of the atmospheric demands usually met by plant transpiration. Any suppression of crop transpiration from the irrigated area as compared to a non-irrigated area can be subtracted from Igross irrigation application losses for a reduced, or net, interception (Inet) loss. This study was conducted to determine the extent in which transpiration suppression due to microclimatic modification resulting from evaporation of plant-intercepted water and/or of applied water can reduce total sprinkler irrigation application losses of impact sprinkler and low energy precision application (LEPA) irrigation systems. Fully irrigated corn (Zea Mays L.) was grown on 0.75 m wide east-west rows in 1990 at Bushland, TX in two contiguous 5-ha fields, each containing a weighing lysimeter and micrometeorological instrumentation. Transpiration (Tr) was measured using heat balance sap flow gauges. During and following an impact sprinkler irrigation, within-canopy vapor pressure deficit and canopy temperature declined sharply due to canopyintercepted water and microclimatic modification from evaporation. For an average day time impact irrigation application of 21 mm, estimated average Igross loss was 10.7%, but the resulting suppression of measured Tr by 50% or more during the irrigation reduced Igross loss by 3.9%. On days of high solar radiation, continued transpiration suppression following the irrigation reduced Igross loss an additional 1.2%. Further 4–6% reductions in Igross losses were predicted when aerodynamic and canopy resistances were considered. Irrigation water applied only at the soil surface by LEPA irrigation had little effect on the microclimate within the canopy and consequently on Tr or ET, or irrigation application efficiency.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00189165
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    Calibration of soil heat flux transducers (1990)
    Springer
    Theoretical and applied climatology 42 (1990), S. 263-272 
    Details
    ISSN: 1434-4483
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Summary Soil heat flux transducer calibration, according to theory, is influenced by the thermal conductivity difference between the transducer and the calibration medium and the geometry of the transducer. This study was conducted to compare the influence of these parameters on the calibration factors of two types of commercial soil heat flux transducers with different material thermal conductivities and different geometries. A theoretical calibration equation was developed and evaluated. Calibrations of 14 transducers representing two commercial types were conducted in the laboratory using steady-state conductive methods over a range of heat fluxes from 40 W/m2 to 200 W/m2. The calibration medium was dry and saturated sand with a thermal conductivity varying from 0.3 to 3 W m−1°C−1. The mean calibration factor for one type of transducer was 12% lower than the mean manufacturer's calibration factor instead of the 26 to 36% lower value predicted by theory. The other type of transducer had a mean calibration factor 7% greater than the mean manufacturer's calibration factor in contrast to the 1 to 11% larger value predicted from theory. The computed geometric factors were 1.07 and 0.89 for the circular and square transducers, respectively. These factors were less than the theoretical value of 1.70 for each shape of transducer but similar to experimental values of 1.02 to 1.31 from previous studies reported in the literature. The thermal conductivity of the calibration medium and the geometry of the transducer affects the calibration factors of soil heat flux transducers, basically according to theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00865987
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Untersuchungen über die Antigenkomponenten der Parathyreoidea (1968)
    Springer
    Clinical and experimental medicine 147 (1968), S. 236-245 
    Details
    ISSN: 1591-9528
    Keywords: Parathyroid gland ; Parathormone ; Antibodies ; Antigens ; Nebenschilddrüse ; Parathormon ; Antikörper ; Antigene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Nach Sensibilisierung von Kaninchen mit Parathyreoideaextrakt vom Rind waren Antikörper nachweisbar, die speciesspezifisch, jedoch nur zum Teil organspezifisch reagierten. Die organunspezifischen Antikörper richteten sich gegen Bindegewebsantigene in verschiedenen Organen, die organspezifischen gegen Antigene im Cytoplasma der Parenchymzellen der Nebenschilddrüsen. Nach Vergleichsuntersuchungen mit einem Parathormonantiserum sind diese jedoch nicht mit dem Parathormon identisch. Parathormon war immunhistologisch nur in einzelnen Zellen bzw. Zellgruppen der morphologisch identischen Parenchymzellen der Rinderparathyreoidea zu vermuten, was auf Unterschiede im Funktionszustand dieser Zellen zurückgeführt werden kann. Der Nachweis organspezifischer Antikörper läßt das Vorkommen einer Immunparathyreoiditis als möglich erscheinen, jedoch ist der exakte Beweis für eine solche Erkrankung bisher noch nicht erbracht.
    Notes: Summary In the serum of rabbits immunized with an extract of bovine parathyroid glands species-specific antibodies were detectable. Part of them reacted with antigens in the connective tissue of parathyroid glands and other bovine organs, while an organ-specific part of the antibodies was directed against antigens in the cytoplasm of parathyroid cells. Further experiments with a rabbit antiserum to bovine parathormone proved that these organ-specific antigens are only partially identical with parathormone. Histochemical techniques showed that parathormone is detectable only in single cells or in groups of cells of the morphologically identical epithelioid cells of bovine parathyroid glands. The fact that organ-specific antigens have been found in parathyroid glands suggests the existence of an “immune parathyroiditis” although this disease has not yet been exactly proved.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02044607
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    Paper (German National Licenses)
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