Chemical structure differences

Comparison of entries 4 and 8 of Table 16 shows that linear IOS 2024 and AOS 2024 adsorption values were the same within a modest experimental error. The major chemical structure difference between them is the position of the sulfonate group on the carbon chain and perhaps the position of the carbon-carbon double bond. These two factors do not appear to have an appreciable effect on adsorption. Therefore, the lower adsorption of IOS 1518 relative to AOS 1618 is probably due to the greater hydrophobe branching of the internal olefin sulfonate or the lower di.monosulfonate ratio. 

Similar molecular weight poly(DMA-co-EPl), 1750 daltons, ca. 13 repeat units, and poly(TMDAB-co-DCB), 1500 daltons, ca. 11 repeat units were compared. The two condensation polymers appeared to be about equally effective in preventing the swelling of Wyoming bento-nite. Any small differences are probably due to repeat unit chemical structure differences rather than the small variations in polymer molecular weight. The presence of the hydroxyl group and the smaller N - N distance in poly(DMA-co-EPl) could affect polymer conforma-tion in solution, geometry of the polymer - clay complex, and surface properties of the polymer - clay complex as compared to poly(TMDAB-co-DCB). 

The chemical structure of PBS also may be altered by exposure to radiation and such changes may contribute to the solubility rate difference between an exposed and an unexposed PBS film. U-type films were prepared from unirradiated powders while IP-type films were prepared from irradiated powders. Inspection of Table II or Figure 2 shows that the three U-type films have slightly larger solubility rates than IP-type films of comparable M. The solubility rate differences between IP and U-type films are small relative to the differences between IP and IF type films. The solubility rate difference between a U and an IP film of comparable M must arise from chemical structural differences between irradiated and unirradiated powders. These radiation-induced changes may also be responsible for differences observed in the elution behavior between irradiated and unirradiated PBS samples in gel permeation chromatography experiments. Irradiated PBS samples yield abnormally broad elution curves while unirradiated samples elute normally I3.8I. 

Part of this data in Table II is a series of British maceral concentrates. The Woolley Wheatly Lime sample is 93% fusinite while the Teversal Dunsil concentrate is 80% semifusinite with 13% fusinite. The Aldwarke Silkstone sample contains 43% semifu-sinite and 43% fusinite. The petrographic analysis of PSOC-2 reveals nearly equivalent amounts of fusinite, semifusinite, micrinite, and macrinite (6.8, 8.1, 7.5 and 8.5% respectively in the whole coal) while PSOC-858 contains primarily semifusinite as the inertinite. The differences in faH values for these iner-tinite samples are greater than the experimental error and these differences suggest that NMR techniques may be useful in characterizing the chemical structural differences between inertinite macerals. 

While broad spectrum anthelmintics (macrolide endectocides, benzimidazole carbamates, tetrahydropyrimidines) largely overlap in the range of endoparasites (mainly nematodes) they affect, the various anthelmintic classes (based on chemical structure) differ in mechanism of action, degree of activity and in pharmacokinetic properties (bioavailability, tissue distribution and... 

The vapor pressure of a solid and the intermolecular interactions it is capable of are ultimately determined by its chemical structure. Differences between the solubilities of solids can also be explained in terms of structural features which limit or enhance solubility. Beginning with a parent compound, the addition of a functional group generally has the effect of reducing solubility. This applies especially to hydroxy (-OH) and carboxy (-COOH) functional groups as described by Stahl et al. [17]. 

Several reviews of Protox herbicides cover the period from the 1960s to 2002 [Ills, 28, 73, 91]. In this section we discuss Protox-related work conducted between 2003 and 2006. Following the momentous volume of research in all aspects of Protox herbicides - their chemistry, biology, biochemistry - in the decades between 1970 and 1990, work in this area of herbicide chemistry has significantly slowed in more recent years. Although corporations have continued to invest in Protox research, with several new structures introduced recently, none of these new chemical structures differ significantly from those already discussed. 

The slightly modified Goldman-Shen experiment employed herein is designed to detect and analyze carbon-13 NMR signals. In this respect, we rely on chemical structural differences as well as motional differences between the two types of segments to assign the i3C spectrum and provide... 

Block copolymers have gained considerable importance in the last three decades. Their special chemical structure (different A and B chains) yields unusual physical properties. Block copolymers frequently exhibit phase separation one block type in a continuous matrix of the second block type. The fact that block copolymers are able to participate in different types of phases gives them special properties both colloidal and mechanical surface activity, surface elasticity, impact modification. 

Thus, the blend components, PIr and Pip, were rather close in their chemical structure differing, however, by the absence or presence of oxygen hinges in the chains. This predetermined the sharply different chain rigidity and allowed one to consider these blends as the PIr/PIp molecular composites consisting of molecular reinforcing fibers and relatively ductile matrix. 

Water uptake varies greatly, depending on the measurement method and its conditions. The most desirable measurement method should reflect both the application and application method. The parameters that control water uptake can be divided into chemical and physical conditions. The former depends on the chemical structural difference of the absorbent (see Section 1.4), including the type of ions, concentration, and the content of the hydrophilic organic solvent in the aqueous solution in the latter, parameters such as the temperature of the absorbate, measurement time, and the presence of pressure are important. 

Figure 2 Chemical structural differences responsible for base stability/instability (verdox, vertenex) and surfactant solubilization (citronellol, linalool).

In general, plasma polymers are amorphous and highly crosslinked materials of irregular chemical structure.Differences in the structures of plasma and conventional polymers should also be reflected in their surface energy properties. 

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