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  • 1
    Electronic Resource
    Electronic Resource
    The hyperbolic shape triangle as a tool for discriminating populations of sediment samples of closely connected origin (1992)
    Oxford, UK : Blackwell Publishing Ltd
    Sedimentology 39 (1992), S. 0 
    Details
    ISSN: 1365-3091
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: This paper describes a new method for discriminating populations of sediment samples of closely connected origin. It provides a dynamical interpretation to grain size data. The descriptive modelling power of the hyperbolic distribution, the hyperbolic shape triangle and the population concept have been applied to several hundred beach sand samples from the Mediterranean coast of southern Israel. The investigated samples are from a 60 km stretch of beach, from Rafah to Ashqelon, and represent an autumn storm profile. The domain of variation of the hyperbolic shape parameters χ and ξ is a triangle referred to as the hyperbolic shape triangle. The distribution of the estimated (χ, ξ) shape positions in the hyperbolic shape triangle was studied graphically and statistically using the newly developed tools described here to present, evaluate and compare hyperbolic shape position data for analysed grain size populations. The graphical methods of contouring the scatter diagrams of the samples in the domain of the hyperbolic shape triangle and chi-squared tests are demonstrated. They were performed on two sedimentary environments normal to the beach, namely inshore and mid-swash zone. The qualitative and quantitative estimated changes in the populations (χ, ξ) shape positions in the shape triangle suggest that they are subjected mainly to ε erosion-deposition processes. Their modes are located along one of the upper ‘hammock’curves in the shape triangle. The location and scale invariant hyperbolic shape parameter ρ indicates a change of the grain size distribution across the left part of the hyperbolic shape triangle, which is the domain of predominantly depositional processes. However, the mid-swash zone sediments reflect that they are subjected more to depositional processes and the inshore sediments more to erosional ones.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3091.1992.tb02145.x
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  • 2
    Electronic Resource
    Electronic Resource
    Resuspension studies in cylindrical microcosms: Effects of stirring velocity on the dynamics of redox sensitive elements in a coastal sediment (1998)
    Springer
    Biogeochemistry 43 (1998), S. 293-309 
    Details
    ISSN: 1573-515X
    Keywords: iron ; manganese ; redox potential ; resuspension ; sediments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Effects of resuspension on the release of dissolved, redox sensitive elements (Fe, Mn) was studied in cylindrical microcosms. Effects from changing water stirring velocity in sediment pools were evaluated through measurements of pore water profiles of dissolved Mn, Fe and redox potential. Mn was a good natural marker to follow such effects. At current velocities below the threshold velocity for resuspension (37 cm s-1), Mn release rates to overlying water were 100 times higher compared to steady-state values. Pulse increases in Mn concentration were the result of convective currents inside flow chambers. These results were strongly supported by measurements of Eh profiles in the sediment pore water. Furthermore, impacts from increasing stirring velocity were found down to 1.9 cm depth below the resuspended layer of sediment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006066610833
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  • 3
    Electronic Resource
    Electronic Resource
    Storage, redistribution and net export of dissolved and sediment-bound nutrients, Vejle Fjord, Denmark (1992)
    Springer
    Hydrobiologia 235-236 (1992), S. 47-57 
    Details
    ISSN: 1573-5117
    Keywords: hydrography ; sedimentation ; resuspension ; nutrients
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sixty three percent of the nitrogen (total transported 2041 × 103 kg y−1) and 17% of the phosphorus (total 159 × 103 kg y−1) supplied from terrestrial sources to Vejle Fjord during the period September 1988 to October 1989 is exported to the Kattegat. The sediment nutrient concentrations in the estuary are mainly governed by hydrography and resuspension. The general wind-induced circulation consists of outgoing currents along the southern side and ingoing currents along the northern side of the estuary. The sediments in shallow water on the southern side had higher concentrations of nutrients. Resuspension resulted in large differences between gross sedimentation and net sedimentation, especially in shallow water. Gross sedimentation of total-N in shallow water was 819 × 103 kg y−1 compared to a net sedimentation of 19 × 103 kg y−1. The shallow water areas in the estuary (10% of the area), had a net sedimentation of total-N which was less than 1% of the supply. Wave-induced resuspension only occurs in exposed parts of the deep water area, when wind velocities exceed 10 m s−1. The concentration of nutrients in the sediments was found to increase with distance from the river (the source) and with increasing depth, as a result of resuspension near the river mouth in the inner part of the estuary. In sheltered parts of the estuary there was no wave-induced resuspension and the net sedimentation equals gross sedimentation. The rate of sedimentation in deep water areas was 12.2 g m−2y−1 for total-N and 2.1 gm−2y−1 for total-P.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00026199
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  • 4
    Electronic Resource
    Electronic Resource
    New sesquiterpene ethers and other constituents isolated from Brazilian vassoura oilDedicated to Professor Kenji Mori on the occasion of his 60th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1995 (1995), S. 1039-1043 
    Details
    ISSN: 0947-3440
    Keywords: Vassoura oil ; Baccharis dracunculifolia ; Compositae ; Sesquiterpene ethers ; Sesquiterpene alcohols ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three new sesquiterpene ethers, 1,6-epoxyeudesm-4(15)-ene (7), 1,11-epoxycadina-4,9-diene (9) and 5,11-epoxycadin-1(10)-ene (10), some sesquiterpene alcohols, e.g. cis- and trans-dracunculifoliol (3) and 4-epi-maaliol (12), as well as 2,2-dimethyl-6-vinylchromene (14) were isolated from Brazilian Vassoura oil. The structures were elucidated by spectroscopic methods.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.1995199506147
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  • 5
    Electronic Resource
    Electronic Resource
    On Some Italicene Derivatives (1996)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1996 (1996), S. 1641-1644 
    Details
    ISSN: 0947-3440
    Keywords: Tricyclic sesquiterpenes ; Italicene derivatives ; α-Copaene derivatives ; Essential oils ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Oxidation of the tricyclic sesquiterpene hydrocarbon italicene (1a) or its 10-epimer 1b (isolated previously from Helichrysum oil) with SeO2 yielded mixtures of italicene-5-one (3a), italicen-15-al (4a), italicen-5-ol (9a) and italicen-15-ol (10a) or their 10-epimers 3b, 4b, 9b, 10b, whereas commercial α-copaene (6) reacted only to give a mixture of α-copaen-15-al (7) and α-copaen-15-ol (8). Jones oxidation of the allyl alcohols 9a or 9b afforded the pure ketones 3a or 3b MnO2 oxidation of the alcohols 10a or 10b furnished the aldehydes 4a or 4b. - Surprisingly, the italicene epoxides 2a or 2b rearranged with diluted HCl to the italicene ethers (epoxyacorenes) 5a or 5b, which previously were isolated from Lantana and Helichrysum oil. - The odor of 3a, 3b, 4a, 4b and 5a was evaluated.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.199619961022
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  • 6
    Electronic Resource
    Electronic Resource
    Terpenes and Terpene Derivatives, XXX. Isolation and Synthesis of Isohumbertiol, the First Naturally Occurring Sesquiterpene Alcohol with a Humbertiane Skeleton (1992)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1992 (1992), S. 1325-1328 
    Details
    ISSN: 0170-2041
    Keywords: Isohumbertiol ; Cabreuva oxide ; Vassoura oil ; Baccharis dracunculifolia ; Sesquiterpenes ; Terpenes ; Humbertiol ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: From Vassoura oil (Baccharis dracunculifolia DC.) the four isomeric isohumbertiols A-D (7-10), the first naturally occurring sesquiterpene alcohols with a humbertiane skeleton could be isolated and assigned unambiguously by establishing a correlation with the known cabreuva oxides A-D (3-6). Reaction of the ketone (+)-16 with vinylmagnesium bromide gave a mixture of the isohumbertiols B and D [(+)-8 and ent-10]. Treatment of 8/10 with SnCl4 furnished the tetraline derivative 18, whereas with hydrochloric acid the cabreuva oxides B and D (4 and 6) were obtained.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.1992199201218
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