Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • controlled-release  (3)
  • Cassava  (2)
  • HPLC  (2)
  • 1
    Digitale Medien
    Digitale Medien
    Amsterdam : Elsevier
    Journal of Pharmaceutical and Biomedical Analysis 7 (1989), S. 119-122 
    ISSN: 0731-7085
    Schlagwort(e): HPLC ; Medroxyprogesterone acetate ; RIA ; comparative plasma concentrations.
    Quelle: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Thema: Chemie und Pharmazie , Medizin
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Nutrient cycling in agroecosystems 17 (1988), S. 235-250 
    ISSN: 1573-0867
    Schlagwort(e): Zinc fertilizer ; controlled-release
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Thermoplastic matrix controlled-release (C.R.) zinc fertilizers are produced by extruding a mixture of zinc salt and inert polymer material. Three methods of laboratory evaluation were used to characterize a range of C.R. zinc formulations differing in concentration and nature of zinc salt, carrier matrix, and size. The methods were (i) electron microscopy, (ii) zinc emission into water, and (iii) zinc diffusion in indicator-agar. These methods complemented each other, with electron microscopy elucidating physical features governing zinc release from the fertilizer pellets. Finely divided particles of soluble zinc salt, for instance, were associated with formulations whose release characteristics approached theoretical (time)0.5 -order release kinetics. Apart from zinc particle size, other factors controlling zinc emission characteristics were the type of zinc salt, the zinc loading, and pellet size. Varying the polymer matrix materials had little or no effect on zinc release from the C.R. zinc formulations compared in this study.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Nutrient cycling in agroecosystems 17 (1988), S. 251-266 
    ISSN: 1573-0867
    Schlagwort(e): Zinc ; controlled-release ; diffusion ; pH ; temperature ; phosphate ; clay ; sand ; moisture content
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract The emission and movement of zinc from planar arrangements of controlled-release (C.R.) thermoplastic matrix zinc fertilizer formulations was studied in cylindrical diffusion cells packed with a clay or a sand. The influences of a number of soil characteristics known to affect zinc diffusion were also investigated. Zinc emission was initially (over 2 days) very rapid. The rate declined markedly thereafter. Morphologically distinct C.R. zinc formulations released zinc at different rates. Zinc moved appreciably and consistently further in the sand than in the clay. Of the soil characteristics studied, increasing phosphate levels had no effect upon zinc emission or mobility in either soil. Increasing pH in the sand did not affect zinc emission, but decreased zinc mobility. Conversely, in the two soils, increasing temperature stimulated zinc emission, but had little influence on zinc mobility. At higher water contents, zinc release was increased in both soils. However, zinc movement was only increased in the sand.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Nutrient cycling in agroecosystems 17 (1988), S. 267-283 
    ISSN: 1573-0867
    Schlagwort(e): Zinc ; controlled-release ; linseed
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Thermoplastic matrix controlled-release (C.R.) zinc fertilizers were compared as zinc sources for linseed (Linum usitatissimum) grown on a zinc-deficient sand and a zinc-deficient clay. C.R. formulations differed in characteristics including origin (different extruders), type of zinc salt, and polymer matrix blends. Conventional fertilization with pure zinc salts was also included in the comparison. C.R. formulations based on zinc oxide (ZnO) were ineffective zinc sources, linseed growth and tissue zinc concentrations being similar to untreated controls. However, both zinc sulphate (ZnSO4·H2O)- and zinc chloride (ZnCl2)-based formulations were effective zinc fertilizers. A group of ZnSO4·H2O-based formulations produced in Melbourne (Australia) gave relatively higher plant zinc concentrations than similar formulations produced on a different extruder in Akron (U.S.A.). Varying the type of plastic or the blend of plastics constituting the matrices of the C.R. products had no consistent effects on tissue zinc concentrations or plant growth. Similarly, no specific benefit of C.R. over conventional zinc fertilization was established under the conditions of the present experiments.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Plant and soil 54 (1980), S. 339-357 
    ISSN: 1573-5036
    Schlagwort(e): Calcium ; Cassava ; Chemical composition ; Control of solution pH ; Copper ; Flowing solution culture ; French bean ; Ginger ; Hydrogen ion injury ; Magnesium ; Maize ; Manganese ; Nitrogen ; Optimum pH range ; pH ; Plant growth ; Root weight ratio ; Tomato ; Wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Ginger, cassava, maize, wheat, french bean and tomato were grown for periods up to six weeks in continuously flowing nutrient solutions at seven constant pH values ranging from 3.3 to 8.5. All species achieved maximum or near-maximum growth in the pH range 5.5 to 6.5. However, there were substantial differences in the ability of species to grow outside this range. Ginger and cassava were the most tolerant species to low solution pH, while ginger and tomato were the only species to show no yield depression at the highest solution pH. Roots of all species at pH 3.3 and some species at pH 4.0 exhibited symptoms of hydrogen ion injury. In addition, the concentrations of magnesium in the tops of all six species, of nitrogen in the tops of tomato and cassava, and of manganese in the tops of maize at these pH values were inadequate for optimal growth. Growth depression at high solution pH was associated with iron deficiency in maize and wheat and with nitrogen and/or copper deficiency in cassava. The relevance of the present results to crop growth under field conditions is discussed. The complex interplay of plant and soil characteristics militates against precise definition of an optimum pH range for the growth of a particular crop unless the soil is also specified.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Plant and soil 59 (1981), S. 179-183 
    ISSN: 1573-5036
    Schlagwort(e): Cassava ; Flowing solution culture ; Mycorrhiza ; Phosphorus nutrition
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary A technique to study mycorrhizal effects on growth and P-uptake of cassava (Manihot escultenta, Crantz) grown in flowing solution culture is described. Phosphorus concentrations were carefully maintained constant at 0.1, 1, 10 and 100 μM by daily analyses and adjustment of the nutrient solutions. Inoculation with mycorrhizal roots hada positiveeffect on P content of plant tissue and/or plant growth only at the two lowest P-concentrations in soulution. These concentrations are two to three orders of magnitude lower than those normally used in conventional nutrient solution cultures.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    Digitale Medien
    Digitale Medien
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 3 (1980), S. 190-192 
    ISSN: 0935-6304
    Schlagwort(e): HPLC ; Routine quantitation of MDI at toxic levels ; Free MDI in prepolymers ; Minimum sample preparation ; Quick ; Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...