Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    The effect of cytochalasin B on the rate of growth and ultrastructure of wheat coleoptiles and maize roots (1979)
    Springer
    Planta 144 (1979), S. 373-383 
    Details
    ISSN: 1432-2048
    Keywords: Auxin ; Cell elongation ; Cytochalasin B ; Dictyosomes ; Secretion ; Triticum ; Zea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cytochalasin B (CB) inhibits the elongation growth of maize roots, and that of wheat coleoptile segments incubated in indolyl-3-acetic acid, by over 30% after a lag period of about 60 min. This long lag is not due to poor tissue penetration by the inhibitor, but seems to reflect a property of the process inhibited by CB. The only visible ultrastructural change accompanying growth inhibition is the accumulation of secretory vesicles in the vicinity of dictyosomes, which occurs between 90 and 300 min. However, a massive accumulation of vesicles is seen after 120 min in root cap cells which possess very active dictyosomes. The results indicate that CB does not inhibit elongation growth by interfering with cytoplasmic streaming. Instead, they indicate that the drug acts to inhibit the secretion of cell wall components at some stage after vesicle production, but prior to their transport.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00391581
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The role of the epidermis in auxin-induced and fusicoccin-induced elongation of Pisum sativum stem segments (1980)
    Springer
    Planta 150 (1980), S. 371-379 
    Details
    ISSN: 1432-2048
    Keywords: Auxin ; Cell elongation ; Epidermis peeling ; Fusicoccin ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of peeling and wounding on the indole-3-acetic acid (IAA) and fusicoccin (FC) growth response of etiolated Pisum sativum L. cv. Alaska stem tissue were examined. Over a 5 h growth period, peeling was found to virtually eliminate the IAA response, but about 30% of the FC response remained. In contrast, unpeeled segments wounded with six vertical slits exhibited significant responses to both IAA and FC, indicating that peeling does not act by damaging the tissue. Microscopy showed that the epidermis was removed intact and that the underlying tissue was essentially undamaged. Neither the addition of 2% sucrose to the incubation medium nor the use of a range of IAA concentrations down to 10-8 M restored IAA-induced growth in peeled segments, suggesting that lack of osmotic solutes and supra-optimal uptake of IAA were not important factors over this time period. It is concluded that, although the possibility remains that peeling merely allows leakage of hydrogen ions into the medium, it seems more likely that peeling off the epidermis removes the auxin responsive tissue.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00390172
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Emulsion copolymerization of butadiene and styrene in the presence of carbon black (1962)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 57 (1962), S. 693-709 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Carbon blacks inhibit and retard free radical polymerization in bulk and solution. The mechanism of this is discussed in terms of the chemical groups present on the carbon surface. It is shown that the number of free radicals which react during the induction period (polymerization of styrene with AIBN) is much less than the number of quinone groups but of the same order of magnitude as the number of easily oxidizable groups. Inhibition by carbon black was also found in an emulsion polymerization system with cumene hydroperoxide as initiator (no reducing components). By use of highly active redox recipes, reasonable rates of polymerization were obtained at both 50°C. (sugar-iron-hydroperoxide recipe) and 5°C. (peroxide-polyamine recipe), with as much as 40 parts of black per 100 parts of monomers. In these systems, the carbon black was charged as an aqueous dispersion stabilized with Daxad 11; the latices were stable and showed evidence of association between some of the carbon black and some of the latex particles. The coagulated rubber stocks, when compounded and cured, gave properties closely similar to those of dry mixed stocks.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1962.1205716555
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Effect of activated gas plasma treatment time on adhesive bondability of polymers (1972)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 16 (1972), S. 1465-1477 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The bondability of the following polymers as a function of length of exposure to excited helium or oxygen was investigated: low-density polyethylene, high-density polyethylene (two types), poly(4-methyl-1-pentene), poly(vinyl fluoride), poly(vinylidene fluoride), FEP Teflon, poly(oxymethylene) copolymer, nylon 6, nylon 66, poly(ethylene terephthalate), and polystyrene. Generally, the bond strength increase rapidly initially and then remains nearly constant, perhaps decreasing in some cases at long exposure times. A method is presented for calculating bond strength-versus-exposure time curves. The calculated curves generally fit the data reasonably well. Polypropylene showed a rapid increase in bondability with exposure to excited oxygen. Helium was ineffective toward this polymer under normal conditions, but could produce good bond strength at higher temperatures.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1972.070160615
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Thermal properties of rigid polymers. I. Measurement of thermal conductivity and questions concerning contact resistanceThis work is drawn in part from the thesis of John A. Hall, submitted in partial fulfillment of the Master of Science degree requirements of the University of Maine at Orono. (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 33 (1987), S. 2029-2039 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Several studies of the influence of contact resistance on the measurement of thermal conductivity of polystyrene using a steady-state device are presented. In each case it is seen that, although this influence can perhaps be minimized, it cannot be eliminated as an experimental complication. A novel technique is then described which does eliminate entirely contact resistance as a variable, and this technique is shown to yield an unequivocal value of thermal conductivity.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1987.070330615
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    An application of the INEPT pulse sequence to the NMR assignment of halogenated marine natural products (1983)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 21 (1983), S. 544-547 
    Details
    ISSN: 0030-4921
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The routine use of the INEPT pulse sequence is shown to be the method of choice for the assignment of multiplicity from 13C NMR spectra where no prior information about the 1J(CH) coupling constants is available, or where these are expected to vary over a large range. This technique is illustrated using spectra obtained from polyhalogenated monoterpenes isolated from the red alga Plocamium angustum, which have 1J(CH) values varying from 127 to 203 Hz.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/omr.1270210905
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Dual capillary column supercritical fluid chromatography (1990)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 13 (1990), S. 22-26 
    Details
    ISSN: 0935-6304
    Keywords: Supercritical fluid chromatography ; Dual capillary columns ; Polycyclic aromatic hydrocarbons ; Hop and beer bitter acids ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A chromatograph equipped with one injection valve, two capillary columns with different selectivities, two flame ionization detectors and two electrometers is used to perform simultaneous dual capillary supercritical fluid chromatography. Two sets of retention times and indices are obtained for a mixture of polycyclic aromatic hydrocarbons, from one injection, enabling positive identification. The system is also used to rapidly select a stationary phase for separating hop and beer bittering acids.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240130106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Activated gas plasma surface treatment of polymers for adhesive bonding (1969)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 13 (1969), S. 2085-2096 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Polyethylene, polypropylene, poly(vinyl fluoride) (Tedlar), polystyrene, nylon 6, poly(ethylene terephthalate) (Mylar), polycarbonate, cellulose acetate butyrate, and a poly(oxymethylene) copolymer were treated with activated helium and with activated oxygen. Mechanical strengths of adhesive-bonded specimens prepared from treated and from untreated coupons were compared. Polyethylene (PE) and polypropylene (PP) showed the greatest increases in bond strength. Oxygen and helium were both effective with polyethylene, but polypropylene showed no improvement when treated with activated helium. The results with excited helium parallel the effects of ionizing radiation on these two polymers, as does the appearance of unsaturation bands in the infrared (965 cm-1 in PE, and 887 and 910 cm-1 in PP). Active nitrogen produced excellent bond strength with polyethylene but not with polypropylene. Of the remaining polymers examined, Tedlar, polystyrene, and nylon 6 showed the greatest improvement in bondability after treatment, and Mylar showed moderate improvement. Polycarbonate, cellulose acetate butyrate, and the poly(oxymethylene) copolymer gave approximately two-fold increases in lap-shear bond strength. In several cases, significant differences in response to time of treatment and type of excited gas were found.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1969.070131006
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Homogeneous anionic polymerization. II. Molecular weight of polystyrene initiated by lithium alkylsPresented in part at the 136th National Meeting, American Chemical Society, Division of Polymer Chemistry, Atlantic City, N. J., September 1959. (1963)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A: General Papers 1 (1963), S. 461-474 
    Details
    ISSN: 0449-2951
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A study has been carried out on the molecular weights and their distribution for polystyrene prepared by means of ethyl and butyl lithium initiators, using benzene and tetrahydrofuran as solvents. Stringent high vacuum techniques were employed in order to minimize any destruction of initiator or termination of growing chains in these anionic polymerizations. Under these conditions, it was found that the stoichiometry corresponded to the formation of one chain from each initiator molecule. Furthermore, the molecular weight distribution could be made very narrow (M̄w/M̄n = 1.05 - 1.1) in these cases, where the initiation reaction was very rapid compared to the propagation step. In the case of the benzene systems, the initiation reaction was too slow, leading to a broadening of the molecular weight distribution, and this could be circumvented by a “seeding” technique whereby all the chain anions were pre-initiated before the main polymerization took place. The alkyl lithium initiators were found to react rapidly with THF at room temperature, but the styryl lithium apparently did not.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1963.100010140
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Polymerization of 4-bromo-2,6-dimethylphenol anion initiated by 2,4,6-tri-T-butylphenoxy radical (1966)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Letters 4 (1966), S. 463-465 
    Details
    ISSN: 0449-2986
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1966.110040705
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...