Influence of Chemical Structure

Ashby, J., and D. Paton (1993). The Influence of Chemical Structure on the Extent and Sites of Carcinogenesis for 522 Rodent Carcinogens and 55 Different Human Carcinogen Estytosurts."Mutation Research 286, 3-74. 

Lunn, G. A. 1982b. The Influence of Chemical Structure and Combustion Reactions on the Maximum Experimental Safe Gap of Industrial Gases and Liquids./. Hazardous Materials, 6, 341-359. 

A. Sokolowski, R. Rai, W. Young, and B. Sjostrom. In vitro intestinal permeability of factor Xa inhibitors influence of chemical structure on passive transport and susceptibility to efflux, Pharm. Res. 2001, 38, 1735— 1741... 

The medicinal chemist expects to find that a review written specifically for him will he mainly concerned with a discussion of structure/activity relationships. In the case of the antihypertensive activity of the (3-blockers such a discussion is not possible since no direct comparative activity data is available either from the laboratory or the clinic (the few comparative clinical studies are in no way definitive - see later). It is however possible to approach the problem somewhat indirectly and consider the influence of chemical structure on those pharma -cological properties which appear most relevant to the specific clinical effect. I propose therefore to -... 

Since the discovery of synthetic dye by Perkin and the establishment of the synthetic organic chemistry industry, a wide variety of synthetic dyes provided a set of choices for staining microbes so that they could be readily examined under the microscope. It is reasonable to suppose that if a dye binds selectively to a microbe much more than to mammalian tissues, then it may be possible to find a dye that selectively harms the microbe and spares the mammal. Paul Ehrlich (figure 1.6) was a medical student who did research in the distribuhon of foreign substances in the body, and he was particularly interested in the influence of chemical structures of different types of molecule in live animals. He observed that acidic dyes with the sulfonic acid function, used by dye manufacturers to enhance water solubility, were unable to penetrate into the brain or fat tissues. 

Ashby, J. and Paton, D. (1993) The influence of chemical structure on the extent and sites of carcinogenesis for 522 rodent carcinogens and 55 different human carcinogen exposures. Mutat. Res., 286, 3-74. 

As in all thermosetting polyimides, the diamine and the tetracarboxylic dianhydride employed to build the backbone can be varied. Alteration of the diamine, tetraacid or both, allow the modification of the polyimide s melting point and solubility. Of interest to the end user is the influence of chemical structure on the melting transition of the prepolymer and the Tg of the fully cured product. Lowering the uncured Tg means increasing flow and, in most... 

Commonly, gas-liquid partitioning is expressed by the saturated liquid vapor pressure, pi, of the compound i. This important chemical property will be discussed in detail in Chapter 4. Briefly, pi is the pressure exerted by the compound s molecules in the gas phase above the pure liquid at equilibrium. Since this pressure generally involves only part of the total pressure, we often refer to it as a partial pressure due to the chemical of interest. In this case, when there is no more build up of vapor molecules in a closed system, we say that the gas phase is saturated with the compound. Note that because pa. is strongly temperature dependent, when comparing vapor pressures of different compounds to see the influence of chemical structure, we have to use pi values measured at the same temperature (which also holds for all other equilibrium constants discussed later see Section 3.4). 

Hedrick JC, Arnold CA, Zumbrum MA, Ward TC, McGrath JE (1990) Poly(arylene ether ketone)/poly(aryl imide) homo- and polydimethylsiloxane segmented copolymer blends influence of chemical structure on miscibility and physical property behavior. 35th International SAMPE Symposium, pp 82-96... 

Guiflard, C., Lachheb, H., Houas, A., Ksibi, M., Elaloui, E. and Herrmann, J.-M. (2003b) Influence of chemical structure of dyes, of pH and of inorganic salts on their photocatalytic degradation by Ti02 comparison of the efficiency of powder and supported Ti02. J. Photochem. Photobiol. A Chem. 158, 27-36. 

FIGURE 5.4 Influence of chemical structure on individual InChl layers. 

Lunn, G. A. The influence of chemical structure and combustion reactions on the maximum experimental safe gap of industrial gases and liquids, Journal of Hazardous Materials 6,1982,341-359... 

In order to investigate the influence of chemical structure on the melt viscosity, polyesters A1.A2.B1 and B2 were compared in the steady mode in plate and plate-geometry at 300°C. A2 and B2 should be in the isotropic region, whereas Al, B1 would be in the nematic state. Prior to steady shear measurements a transient step from... 

A comparative study on the influence of chemical structure and solubility of a series of low-molecular-weight 1,4-phenylene-bisamides in i-PP was conducted to explore their performance as electret additives [30]. Bisamides are also capable of forming well-defined nano-aggregates via self-assembly from the i-PP melt upon cooling. Here, a comparison of a dicyclohexyl-substituted 1,4-phenylene-bisamide 5 and the asymmetrically substituted cyclohexyl/ -alkyl-l,4-phenylenebisamide 6 will be presented the chemical structures are included in Fig. 24. The symmetry of the molecule, the type of substitution, and the length of the alkyl chain have an influence on the solubility in the i-PP melt while the nucleation efficiency and the ratio of the a- to [3-crystal modification will have an effect on the charge storage properties. 

FIGURE 3.19 VI as a function of CMRP content for group II and in base stocks. Source V. J. Gatto M. A. Grina, T. L. Tat, H. T. Ryan. The Influence of Chemical Structure on the Physical and Performance Properties of Hydrocracked Basestocks and Polyalphole-fins, Journal of Synthetic Lubrication 19 13-18 (2002). With permission. 

Table IV. Laboratory Comparison of Influence of Chemical Structures...

The chemical structure and physical properties of the polymer should be primarily considered for the choice of polymer materials. However, there are only a few literature reports on the influences of chemical structure of polymers on the properties of the derived carbon membranes, e.g. by Park et al and Xiao et The latter reported the structure and properties relationship for polymers based on the experiment and simulation approaches, which provided considerable information for the choice of suitable polymers for carbon... 

The compound on the left is solid at room temperature (melting point of 137.5 C). The compound on the right is liquid (melting point -30°C). This shows the main direction of influence of chemical structure on the properties of the plasticizer. 

INFLUENCE OF CHEMICAL STRUCTURE ON THE (DE)VITRIFICATION BEHAVIOUR OF THE THERMOSETTING SYSTEMS... 

The influence of chemical structure of flexible decouplings in pol3dere-phthaloyl-bis ( -oxybenzoates) on their mesogenic properties was studied in Ref [131], The studied were the polymers, which had asymmetrical centers, introduced into the flexible methylene decoupling and also complex ester groups ... 

Influence of Chemical Structure on Glass Transition Temperature... 

Y. Chang, Y.B. Ixe, C. Bae, Partially fluorinated sulfonated poly(ether amide) fuel cell membranes influence of chemical structure on membrane properties. Polymer 3 (1) (2011) 222-235. 

There are very few reports on biodegradation of MTBE. MTBE is a very persistent chemical (Yeh and Novak, 1994). All indications are that it will biodegrade slowly in suitably acclimated conditions. Suflita and Mormile (1993) have found that oxygenates containing a tertiary or quaternary carbon atom were much more recalcitrant than their unbranched or not so hindered counterparts. The strong influence of chemical structure on biodegradation has been known for decades. For example, K-butyl methyl ether has been shown to degrade at a faster rate than MTBE under similar suitably acclimatized systems. 

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