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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Trees 1 (1987), S. 88-93 
    ISSN: 1432-2285
    Keywords: 1Gas chromatography ; Picea abies ; Solvent extraction ; (Mono)terpene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary An analysis was made of the effects of different sampling and extraction techniques on the amounts and pattern of monoterpenoids isolated from needles of Norway spruce. The following isolation and analysis procedure was finally adopted: liquid nitrogen-cooled needles were pulverized by a microdismembrator, extracted with pentane overnight at 2°–3°C and concentrated to a volume not less than 3 ml/g fresh weight on a Vigreux column. The crude extract was injected splitless (with solvent split) onto a cold programmed temperature vaporized (PTV) precolumn of a gas chromatograph and the vaporizable compounds heated to a capillary column. This method was tested for production of artefacts and quantitative extraction and applied to needles of eleven 80-year-old spruce trees.
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  • 2
    ISSN: 1432-2285
    Keywords: Picea abies ; (Mono) terpenes ; Needle ; Variability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The extractable monoterpenes from needles of two groups of trees — 4-year-old clonal and 20-year-old wild trees — were studied with respect to the influence of individual constitution, needle age, whorl position, and position on branch. Leaf terpene amounts from clonal trees are significantly affected by age and position of the whorl, whereas position on the branch is of minor importance. Developing needles of clonal trees are most strongly affected by age and whorl position and they differ markedly from mature needles in quantitative terpene composition. Wild trees exhibit a very high variation from tree to tree, which obscures the influence of needle age and position. For this reason meaningful tree leaf terpene data will only be derived if large samples of needles of different ages are collected from distinct positions. When comparing different trees, needles should be selected that not only have the same state of development, but also originate from identical positions and have been subjected to the same light treatment.
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  • 3
    ISSN: 1432-2285
    Keywords: Picea abies ; (Mono) terpenes ; Needle ; Variability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The extractable monoterpenes from needles of two groups of trees — 4-year-old clonal and 20-year-old wild trees — were studied with respect to the influence of individual constitution, needle age, whorl position, and position on branch. Leaf terpene amounts from clonal trees are significantly affected by age and position of the whorl, whereas position on the branch is of minor importance. Developing needles of clonal trees are most strongly affected by age and whorl position and they differ markedly from mature needles in quantitative terpene composition. Wild trees exhibit a very high variation from tree to tree, which obscures the influence of needle age and position. For this reason meaningful tree leaf terpene data will only be derived if large samples of needles of different ages are collected from distinct positions. When comparing different trees, needles should be selected that not only have the same state of development, but also originate from identical positions and have been subjected to the same light treatment.
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  • 4
    ISSN: 1432-2285
    Keywords: Bavaria ; Genetic variation ; Needle ; Picea abies ; (Mono)terpene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary As genetic diversity is an important cause of variation in needle monoterpenes of conifers, the tree-to-tree variation was studied for Picea abies (L.) Karst. at eight different locations in three mountainous regions of southern Germany (Bavaria). The tree-to-tree variation, expressed by the coefficients of variation, is high, ranging between 50% and 70%. The maximum concentrations per tree are up to 10 times higher than the minimum ones. The trees from all locations show similar patterns of variation, which is significant when investigating the influence of external parameters like air pollution or infestation by pathogens. By means of cluster analysis five types of terpene patterns were clearly revealed. Two main groups were distinguished by their proportion of myrcene, and they are further divided into subgroups. The patterns are stable throughout different needle ages and dates of sampling. Apart from one location, there is no obvious geographical arrangement of the five patterns. The fact that no relationship exists between the genotypical classification and the total concentrations agrees well with the hypothesis that most of the variability based on the relative amounts is due to genetic variation, whereas the variation based on the absolute amounts reflects environmental factors.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 326 (1987), S. 391-399 
    ISSN: 1434-601X
    Keywords: 12.35.Ht ; 21.60.Cs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Model calculations for nuclear properties such as shell structure, magnetic moments and charge distributions are presented where quarks instead of nucleons are used as the fundamental nuclear constituents. It is shown that such a new picture is able to reproduce the gross properties of the classical theory. Nucleons and nuclearΔ-resonances show, however, a partial quark deconfinemement which leads to Pauli-blocking.
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