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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 111 (1988), S. 121-126 
    ISSN: 1573-5036
    Keywords: barley ; decomposition ; fertilization ; green manure ; liming ; N-budget ; N-release ; 15N ; red clover
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Red clover material labelled with15N was confined in mesh bags and buried into microplots in October at two field sites in Sourthern Finland. The soils (Kettula silt loam and Långvik loam) contained in the microplots were previously limed and fertilized with PK (N was given in next May) in different combinations. The following May the microplots were sown with barley and after the barley had been harvested (that August) soil samples and the mesh bags were removed. The crop, mesh bags and soil were then analysed for15N content. The soil treatments did not affect the release of clover N from the mesh bags and only slightly its retention in Kettula silt loam. The dry mass of barley obtained responded strongly to the different soil treatments. In comparison, the uptake of clover N by the barley varied much less; in Kettula silt loam a 1.6 fold increase in barley dry mass did not affect its content of clover N (12–13% of input) and in Långvik loam a ten fold increase in barley dry mass yield corresponded to a three fold increase of the content of clover N (5–16%). The total recovery of clover N (clover N in soil+mesh bags+barley harvest) was almost independent of the soil treatment; in Kettula silt loam and Långvik loam being respectively 52–56% and 71–85% of the input.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 105 (1988), S. 133-139 
    ISSN: 1573-5036
    Keywords: field bean ; green manure ; mesh bag ; N cycling ; N loss ; N-15 ; red clover ; subterranean clover ; timothy ; white clover
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Release of N, retention in soil, availability to a subsequent crop and total recovery of N derived from different15N-labelled plant materials decomposing in soil was investigated in two field experiments. In the first experiment five different plant species (white clover, red clover, subterranean clover, field bean and timothy) and in the second subterranean clover of different maturity (2,3 and 4 months old) were buried in mesh bags in the soil and allowed to decompose for 10 and 4 months, respectively. Most of the N released from the decaying plant materials was retained in the soil (27–46% of input). The subsequent crop (barley) took up 6–25% of input. The uptake correlated with the amount of N released from the decomposing material (r=0.936*, I experiment). Similar amounts of subterranean clover N were taken up by barley regardless to whether the material was buried in soil in the previous autumn or just before sowing of the crop. At the end of the experiments, the total recovery of the introduced plant-derived N varied between 89 and 102%. The results present evidence that the ability of the soil to retain plant-derived N is strong in comparison with the ability of the subsequent crop and different loss mechanisms to remove it.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 105 (1988), S. 141-147 
    ISSN: 1573-5036
    Keywords: barley ; decomposition ; green manure ; N-budget ; N-release ; N-15 ; soil type ; subterranean clover
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Seven soils were collected from different field sites in Southern Finland and placed into microplots confined in PVC-cylinders (30 cm i.d. × 50 cm). Subterranean clover material labelled with15N, contained in mesh bags, was buried into the microplots in October, and the plots were sown with barley the following May. The mesh bags were removed and soil samples taken immediately after the barley harvest. The crop, mesh bags and soil were then analysed for15N content. The soil type affected release of clover N from the mesh bags and its retention in soil only slightly; at the end of the experiment the mesh bags contained 30–38% and the soil (0–45 cm) 28–37% of the clover N input. The uptake of clover N by the barley crop varied from 11 to 20% and correlated best with the soil electrical conductivity (r=0.820*). The total recovery of clover-derived N varied from 72 to 92%.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 105 (1988), S. 149-152 
    ISSN: 1573-5036
    Keywords: C release ; liming ; mesh bag ; Nitrogen ; N release ; red clover
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Red clover root material confined in mesh bags was buried in three different limed and unlimed soils and incubated for 196 days at room temperature. Remaining amounts of organic matter, as well as concentrations of C and N of the decomposing material were determined three times during the incubation and finally the concentration of soil mineral N and pH of remaining roots was also assessed. Liming only temporarily affected the decomposition rate of organic matter and N release, and at the end of the incubation no effects could be observed due to liming. A possible explanation is that the decomposing root residues provide a well buffered micro-environment for the decomposing microflora. Liming did not change the pH of the root residues even when 97–98% of dry mass had disappeared from the mesh bags. Concentrations of mineral N were higher in limed than in unlimed soils.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 102 (1987), S. 185-191 
    ISSN: 1573-5036
    Keywords: green manure ; leaching ; loam ; nitrogen ; nitrogen budget ; N-15 ; subterranean clover
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The leaching of subterranean clover-derived N (15N) was investigated in a laboratory and a field experiment. In both experiments 30 cm i.d. ×50cm soil columns were used. In the laboratory experiment the clover material was buried in the soil in mesh bags, and leaching of clover-derived N was compared to leaching of added NH 4 + −N and NO 3 − −N over a period of 75 days at 20°C. During that time 75% of the clover-N was released from the mesh bags and 17% of the clover-N, 50% of the NH 4 + −N and 70% of the NO 3 − −N was leached through the soil column. In the field experiment 6 lysimeters and 7 control microplots were constructed. The clover material was buried in soil (to the soil of two control microplots within mesh bags) in October. During one year 2% of the added clover-N was leached. This was despite a release of 65% of the N from the mesh bag contents and despite a 26% loss of the clover-derived N in total from the controls.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 189 (1988), S. 2823-2837 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The commercially available poly(1-octenylene) Vestenamer® formed by the metathetic polymerization of cyclooctene with a tungsten catalyst, is highly crystalline at room temperature; it shows specific properties as a blend component, thus favourably influencing the processing characteristics and the final product quality. Differential scanning calorimetry, infrared and torsion pendulum experiments indicate that the melting temperature and the degree of crystallinity depend on the concentration of trans double bonds, on their distribution along the polymer chain as well as on the sample history. The formation of crosslinks induced by very intensive UV irradiation of 100 μm thin films leads to a reduction of the melting temperature and the crystallinity. A correlation between stiffness (shear modulus G′) and crystallinity was found for samples with varying amounts of trans double bonds.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 179 (1978), S. 1821-1835 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The scattering behaviour and the critical conditions where gelation takes place have been calculated for polycondensates formed under constraints. The general model includes fully random and stringently restricted reactions as limiting cases. Also polycondensates of glycerine-type monomers are included as special cases. The particle scattering factors of the f-functional random polycondensates differ remarkably from those polycondensates formed under strict constraints. The former show a Kratky plot of a simple curve, independent of the magnitude of the molecular weight and the number of functional groups, and the curve approaches a constant asymptote of u2·Pz(u)=3, the latter exhibits a maximum at u2=6 which becomes more pronounced with increasing molecular weight, (u2 = 〈S2〉zh2, with h, the value of the scattering vector). The scattering curves of the polycondensates formed under weak constraints show at low molecular weights the same behaviour as those formed under stringent constraints, but approach the behaviour of random polycondensates at large molecular weights. The scattering curves of the glycerine-type polycondensates show no deviations in shape from random polycondensates.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 367-374 
    ISSN: 0170-2041
    Keywords: Concave base ; 1,10-Phenanthroline ; Macrobicyclic lactam ; Template cyclization ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Konkave Reagenzien, 2. - Makrobicyclische 1,10-PhenanthrolineDrei makrobicyclische 2,9-disubstituierte 1,10-Phenanthrolin-bislactame 4 wurden mit Gesamtausbeuten bis zu 43% synthetisiert. Dabei wurden zwei Makrocyclisierungstechniken angewandt: 1) Eine Metallionen-gesteuerte Biskondensation (Templatsynthese) eines Diamins 6 mit 1,10-Phenanthrolin-2,9-dicarbaldehyd (5) führte zu neuen makrocyclischen 1,10-Phenanthrolin-Diimin-Komplexen 7 (Schiff-Basen, als Pb2⊕-Komplexe isolierbar), die durch Reduktion mit NaBH4 in die makrocyclischen Diamine 8 übergeführt werden konnten. 2) Die makrocyclischen Diamine 8 wurden mit Dicarbonsäuredichloriden 9 nach dem Verdünnungsprinzip zu den Makrobicyclen 4 umgesetzt. - Die Synthesen der Bicyclen 4, ihre Reaktionen mit Cu⊕ und die relativen Basizitäten von 4 und Vergleichsverbindungen in Ethanol werden beschrieben.
    Notes: Three macrobicyclic 2,9-disubstituted 1,10-phenanthroline-containing bislactams 4 were synthesized in overall yields of up to 43%. Two successive macrocyclization techniques were used: i) metal ion template-assisted bis-condensations of diamines 6 with 1,10-phenanthroline-2,9-dicarbaldehyde (5), leading to new macrocyclic 1,10-phenanthroline-diimine complexes 7 (Schiff bases, isolable as their Pb2⊕ complexes), which were then reduced with NaBH4 to yield the macrocyclic diamines 8, and ii) a high dilution cyclization reaction between the macrocyclic diamines 8 and diacyl dichlorides 9. - Syntheses, complexing abilities towards Cu⊕, and relative basicities of 4 and related compounds in ethanol are reported.
    Additional Material: 2 Tab.
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  • 9
    Electronic Resource
    Electronic Resource
    Basel : Wiley-Blackwell
    ISSN: 0173-2803
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Biopolymers 24 (1985), S. 461-482 
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Mechanical creep and creep recovery in small shearing deformations have been studied in unligated clots formed with both thrombin and ancrod. In thrombin clots, both A binding sites (which interact with “a” sites to link monomer units within a protofibril) and B sites (which interact with “b” sites to form links between protofibrils) are exposed to enable formation of linkages; in ancrod clots, only the A sites are exposed. Fine clots (with minimal lateral aggregation of protofibrils), coarse clots (with substantial aggregation of fibril bundles), and clots of intermediate coarseness were compared. Fine thrombin clots showed less creep at short times but more creep at long times than coarse or intermediate clots and had more irrecoverable deformation relative to the initial elastic deformation. Ancrod clots had greater irrecoverable deformation than the corresponding thrombin clots, both fine and coarse. The permanent deformation in fine ancrod clots was enormous, corresponding almost to fluid character; the rate of permanent deformation was larger than that in fine thrombin clots by more than two orders of magnitude. For all types of clots, differential measurements of compliance (or its reciprocal, elastic modulus), as well as the applicability of the Boltzmann superposition principle to calculation of creep recovery, showed that the overall density of structure remained constant throughout the mechanical history; i.e., if structural elements were breaking, they were reforming at the same rate in different configurations. The possibility that the weakness of ancrod clots is attributable to partial degradation of α-chains rather than absence of Bb linkages was eliminated by comparisons of clots made with thrombin, ancrod, and ancrod plus thrombin; the last two showed identical partial degradation of α-chains (by gel electrophoresis), but the first and third had essentially identical initial elastic moduli and creep behavior. Two alternative mechanisms for irrecoverable deformation in fine clots are discussed, involving rupture of protofibrils and slippage of twisted segments, respectively.
    Additional Material: 12 Ill.
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