Influence of Molecular Structures

Among other factors that may influence the photochromic effect, covalent insertion of inert spacers may minimize the steric hindrance of pendant chromophores, thus providing enhanced mobility to move away responsive species from a bulky polymer backbone [14]. Again, enhanced free volume by the incorporation of alkyl spacers in PMMA was shown to be beneficial to enhance the responses [23]. More complex behavior is shown in liquid crystaUine polymers, where in addition to the 

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In another study (Gage and Holm 1976), the influence of molecular structure was studied on the rate of excretion by mice for 14 different congeners. The results were as follows ... 

Gage, J.C. and Hohn, S. (1976). The influence of molecular structure on the retention and excretion of PCBs by the mouse. Toxicology and Applied Pharmacology 36, 555-560. 

Bednarczyk D, Ekins S, Wikel JH and Wright SH. Influence of molecular structure on substrate binding to the human organic cation transporter, hOCTl. Mol Pharmacol 2003 63 489-98. 

Nonomura, Y. et al., Spectroscopic properties of chlorophylls and their derivatives. Influence of molecular structure on the electronic state, Chem. Phys., 220, 155, 1997. 

Funami, T., Hiroe, M., Noda, S., Asai, I., Ikeda, S., and Nishinari, K. (2007). Influence of molecular structure imaged with atomic force microscopy on the rheological behavior of carrageenan aqueous system in the presence or absence of cations. Food Hydrocolloids 21, 617-629. 

J. Weiss, J.N. Coupland, D. Brathwaite, and D.J. McClements Influence of Molecular Structure of Hydrocarbon Emulsion Droplets on Their Solubilization in Nonionic Surfactant Micelles. Colloids Surfaces A 121, 53 (1997). 

Two pattern recognition techniques are applied to the analysis of the library of FTIR spectra compiled by the US EFA> The patterns which emerge demonstrate the influence of molecular structure on the spectra in a way familiar to chemical spectroscopists They are also useful in evaluation of the library, which is not error free, and in assessing the difficulties to be expected when using FTIR spectra for complex mixture analysis. 

Edelmann, A. et al., Dynamic light scattering study of the complexation between proline rich proteins and flavan-3-ols influence of molecular structure, polyphenol/protein ratio and ionic strength. In Oenologie 2003 (eds A. Lonvaud-Funel, G. De Revel, and P. Darriet), Tec et Doc, Arcachon, 2003, p. 408. 

H.M. Lauti Orientation of macromolecules and elastic deformations in polymer melts. Influence of molecular structure on the reptation of molecules. Progr. Colloid Polymer Sci. 75 (1987) 111-139... 

IV. Influence of Molecular Structure on the Shape of the Tritium /f Spectrum and the Problem of Determining the Neutrino Rest Mass... 

Molecularly Related Nitrophenols. To define more explicitly the relative influences of molecular structure and hydrophobic character upon rate of adsorption of pesticide materials by porous carbon, a number of pure dinitrophenols molecularly related to DNOSBP and DNOCHP have been studied. The molecular structures of DNOSBP, DNOCHP and the molecularly related dinitrophenols—DNP, DNC, DNT, and DNPCHP —are illustrated in Figure 5. 

THE INFLUENCE OF MOLECULAR STRUCTURE ON RATES OF PROTON-TRANSFER REACTIONS... 

The influence of molecular structure on rates of proton-transfer... 

Since it is not the objective of this chapter to give either a complete review of all organic photoreactions or an exhaustive account of the applicability of the various theoretical models, neither of these classifications is followed strictly. Instead, the interpretation of experimental data by means of theoretical models will be discussed for selected examples from different classes of compounds or reaction types in order to elucidate the influence of molecular structure and reaction variables on the course of a photochemical reaction. 

The influence of molecular structure on the degradation mechanism of degradable polymers of poly(tri-methylene carbonate), poly (trimethylene carbonate-co-caprolactone), and poly(adipic anhydride) was explored by Albertsson and Eklund [7]. Measuring the change of the mass and the molecular weight for the... 

Influence of Molecular Structure and Substituents on Antiozonant Properties of Aryl Diamine Compounds... 

The influence of molecular structures and substituents on the antiozonant properties of a series of related aromatic diamine compounds was studied. The relative effectiveness of the compounds was determined by viscometric techniques and by comparison of the rate of degradation of protected vuicanizates. Results indicate that unsymmetrical p-phenylenediamine derivatives are less effective than analogous symmetrical compounds as antiozonants. The protective capacity of the antiozonants decreases as the size or number of the N-hydrogen substituents, or the distance between the amine groups, increases. The comparative stability of the free radicals of aryl diamines, in terms of the theory of resonance, is utilized to explain the relative inhibiting properties of the chemicals examined. 

Influence of Molecular Structure. The changes in per cent of initial viscosity index with ozonization time for SBR solutions protected by symmetrical and un-symmetrical aryl diamine compounds are shown in Figures 1 and 2. Figure 3 compares... 

Grosche and Martin investigated the influence of molecular structure on mobility for several polycationic and zwitterionic systems. In the case of poly(2-vinylpyridines) and poly(4-vinylpyridines) dependence of mobility on size was observed in the range 5300-257,000 g mol-1 the dependence was smaller for the ortho compounds (Fig. 22) than for the para molecules (Fig. 23) [34]. However, these compounds can only be separated by CGE according to molecular size, as discussed above. 

V.V. Grigo ev, Influence of Molecular Structure on Physicochemical and Service Properties of Synthetic Oils, Chem. Tech. Puels Oil, 35(2), 94—97, Mar.-Apr. (1999). 

Weiss, J. et al.. Influence of molecular structure of hydrocarbon emulsion droplets on their solubihzation in nonionic surfactant micelles. Colloids Surf. A, 121, 53, 1997. 

Recent evidence indicates that the influence of molecular structure on gas permeation through polymers is complex. For example, reports investigating series of structurally varied polyimides (5-7), polyacetylenes (2), polystyrenes (2) and silicone polymers (12) show that gas transport rates within a particular polymer class can vary dramatically depending upon the structure of the monomer present. These observations on materials where the monomer changes while the functional "link" remains constant suggest that structural factors other than the polymer class are significant in determing gas transport properties. 

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