Polyamines light

In presence of polyamines the maximum of light absorption of indicated triphenylmethane dyes displaces on 10-30 nm, for azo dyes the shift of the band reaches 50-80 nm. The greatest difference of light absorption of associates and reagents is watched for BKM at pH 5,05, for BPR at pH 4,20, for CPR in an interval pH 5,05-5,45. At these pH dyes are anions, it promotes interaction with a cationic surface-active substance. The ratios between polymer and BKM, BPR, CPR are established by spectroscopy method, its equal 1 20, 1 20 and 1 30 accordingly. 

Polybutadienes, polycaprolactones, polycarbonates, and amine-terminated polyethers (ATPEs) are shown in Scheme 4.4 as examples of other commercially available polyols. They are all specialty materials, used in situations where specific property profiles are required. For example, ATPEs are utilized in spray-applied elastomers where fast-reacting, high-molecular-weight polyamines give quick gel times and rapid viscosity buildup. Polycarbonates are used for implantation devices because polyuredtanes based on them perform best in this very demanding environment. Polycaprolactones and polybutadienes may be chosen for applications which require exceptional light stability, hydrolysis resistance, and/or low-temperature flexibility. 

Excess of the reagent hydrolyses to a non-fluorescent residue and the reagent itself does not fluoresce. The optimum wavelength of the excitation light is 390 nm and that of the emitted light 475 nm. This regent is, however, less sensitive than Fluoropa and the derivative is unstable consequently, it must be injected onto the column immediately after formation if used in pre-column derivatization. It has been used successfully in the separation and analysis of polyamines (32), catecholamines (33) and amino acids (34). 

Chitosan films are also transparent in the UV and visible regions of the light spectrum and thus have little effect on most optical detection methods. Also, chitosan s amine groups are more reactive in aqueous environments compared to other polyamines because of the low pKa value possessed by the primary amine (6.3 for chitosan vs. 10.5 for polylysine). Finally, other advantages of chitosan are that it is safe, abundant and inexpensive. 

Della Mea, M., Di Sandro, A., Dondini, L., Del Duca, S., Vantini, F., Bergamini, C., Bassi, R., and Serafini-Fracassini, D., A /ea mays 39-kDa thylakoid transglutaminase catalyzes the modification by polyamines of light-harvesting complex II in a light-dependent way, Planta, 219, 754—764, 2004. 

Molded foam copolymers with 10-30% glycidyl acrylate may be crosslinked by heating in the presence of polyamines. Heat resistance may be increased to as high as 150°C. by this treatment (25). Use of certain allyl or diallyl esters to control the crosslinking of polystyrene to the desired very light extent has been disclosed as a means of obtaining foams of improved and regular cell structure (135). Block copolymers of polystyrene, polydiene (particularly polyisoprene), and polystyrene... 

Ruthenium complexes are of interest in light harvesting and electron transfer. Therefore many groups have been incorporating ruthenium complexes into a variety of macromolecular systems (for a review, see reference 236). We have successfully prepared ruthenium-containing polythiols, 102, and polyamines, 103, from bpy ruthenium complexes.237,238,239... 

Amorim et al. (1976, 1977) using thin-layer chromatography isolated and identified polyamines from green coffee beans putrescine and spermine. These products are degraded during roasting, except putrescine which could be detected in the light roasted coffee. 

Identified in green and roasted beans by Amorim et al. (1977) by fluorometry and densitometry of the dansyl (5-dimethylamino-l-naphthalenesulfonyl) derivative by TLC. Unlike to the other polyamines, putrescine could be detected in the light-roasted coffee (1-3 ppm), but the polyamine content does not... 

Elicitors of the Phytoalexin Response. The production of phytoalexins can be elicited not only by living organisms, but also by many chemical compounds and stress situations (27,46,47). Hg" (48) and Cu (49) ions, fungicides (50,51), and polyamines (52) are some of the different chemical elicitors of phytoalexins. Physical stresses such as cold (53) and UV light (54,55) also stimulate the phytoalexin response. Even though these different stresses may act at different sites and in different ways, the result is always a dramatic change in metabolism of the susceptible plants. 

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