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Functionalization chemical structure

The examples of reaction rates of O2 in Figure 12.7 show that O2 reacts only with deprotonated species (e.g., phenolate anions) that is, the apparent rate constants decrease in the pH region below the pKa of the chemical. Singlet oxygen is selective it is an electrophile that reacts only with particular functional chemical structures such as are present in 1,3 dienes (see chemical structure of fiirfuiyl alcohol) or polycondensed aromatic hydrocarbons (with delocalized 7T electron bonds) or in sulfides or mercaptans (Hoigne, 1990). [Pg.741]

Predicted Biological Activity = Function (Chemical Structure)... [Pg.1311]

Uchida M, Tanizaki T, Gda T and Ka]iyama T 1991 Control of surface chemical-structure and functional property of Langmuir-Blodgett-film composed of new polymerizable amphiphile with a sodium-sulfonate Maoromoieouies 24 3238-43... [Pg.2633]

In practice, each CSF is a Slater determinant of molecular orbitals, which are divided into three types inactive (doubly occupied), virtual (unoccupied), and active (variable occupancy). The active orbitals are used to build up the various CSFs, and so introduce flexibility into the wave function by including configurations that can describe different situations. Approximate electronic-state wave functions are then provided by the eigenfunctions of the electronic Flamiltonian in the CSF basis. This contrasts to standard FIF theory in which only a single determinant is used, without active orbitals. The use of CSFs, gives the MCSCF wave function a structure that can be interpreted using chemical pictures of electronic configurations [229]. An interpretation in terms of valence bond sti uctures has also been developed, which is very useful for description of a chemical process (see the appendix in [230] and references cited therein). [Pg.300]

The Wiswesser Line Notation (WLN) was introduced in 1946, in order to organize and to systematically describe the cornucopia of compounds in a more concise manner. A line notation represents a chemical structure by an alphanumeric sequence, which significantly simplifies the processing by the computer [9-11], (n many cases the WLN uses the standard symbols for the chemical elements. Additionally, functional groups, ring systems, positions of ring substituents, and posi-... [Pg.23]

B and W J Howe 1991. Computer Design of Bioactive Molecules - A Method for Receptor-Based Novo Ligand Design. Proteins Structure, Function and Genetics 11 314-328. i H L 1965. The Generation of a Unique Machine Description for Chemical Structures - A hnique Developed at Chemical Abstracts Service. Journal of Chemical Documentation 5 107-113. J 1995. Computer-aided Estimation of Symthetic Accessibility. PhD thesis. University of Leeds, itan R, N Bauman, J S Dixon and R Venkataraghavan 1987. Topological Torsion A New )lecular Descriptor for SAR Applications. Comparison with Other Descriptors. Journal of emical Information and Computer Science 27 82-85. [Pg.740]

The organic chemical structural types believed to be characteristic of coals include complex polycyclic aromatic ring systems with connecting bridges and varied oxygen-, sulfur-, and nitrogen-containing functionalities. [Pg.132]

StiJl, D. R., F. F. Westnim, Jr., and G. C. Sinke, The Chemical Thermodynamics of Organic Compounds, John Wiley and Sons, New York, 1969. Stuper, A. J., W. E. Brugger, and P. C. Jurs, Computer Assisted Studies of Chemical Structur e and Biological Function, John Wiley and Sons, New York, 1979. [Pg.383]

Organofunctional silane Chemical structure of organofunctional group Functional groups used... [Pg.46]

As it is seen from Eq. (23), the thermodynamic opportunity of the reaction initiation (AG = 0) is defined by network properties (Ccon, fix, Tiim), as well as by the conditions of production, storage, and exploitation (/iph, a), and by external influence (T, A). As mentioned previously, the Ccon value is the function of chemical structure of the network and the solvent (in a number of cases the solvent amount disposed in the network may depend on ph and intermolecular bonds distribution). [Pg.366]

An infrared beam is directed through a crystal of refractive index (ni) onto a sample of smaller refractive index (n2). The intensity of the reflected beam is monitored as a function of the wavelength of the incident beam. These absorptions are used to identify the chemical structure. ATR has a sampling depth of about 0.3-3.0 microns. [Pg.517]

This article, while not being intended to provide a full account of poly(arylene)s, emphasises the synthetic aspects. The synthesis of conjugated oligomers and polymers is, however, always part of an interdisciplinaiy approach with their active physical function being a key concern. In that sense the research being reviewed above concentrates on physical properties rather than playing with exotic chemical structures. [Pg.43]

Ribosomal Protein Synthesis Inhibitors. Figure 3 The chemical structure of tetracycline and possible interactions with 16S rRNA in the primary binding site. Arrows with numbers indicate distances (in A) between functional groups. There are no interactions obseived between the upper portion of the molecule and 16S rRNA consistent with data that these positions can be modified without affecting inhibitory action (from Brodersen et al. [4] with copynght permission). [Pg.1088]

Structure activity relationships, i.e., the total pattern of change in a biological activity as a function of chemical structure, typically derived from a comparison within a chemical series so that the biological effects of substitution at each structural position may be determined and correlated. [Pg.1107]

Because of the unambiguous reactive sites of monomers and the high chemo-and stereoselectivity of transition-metal-catalyzed coupling reactions, polymers prepared by transition metal coupling have predictable chemical structures. Functional groups can be easily and selectively introduced at the desired position within die polymer chains. Therefore, polymers widi specific properties can be rationally designed and synthesized. [Pg.477]

Functionally, accelerators are classified as primary or secondary. Primary accelerators provide considerable scorch delay, medium fast cure, and good modulus development. Secondary accelerators, on the other hand, are usually scorchy and provide very fast cure. There are a wide variety of accelerators available to the compounder including accelerator blends this number well over 100. In order to rationalize the extensive range of materials it is useful to classify them in terms of their generic chemical structure listed below and shown in Figure 14.4. [Pg.417]

With the discussion of oxygenafe, pofentially bioderived, fuels and fuel additives such as alcohols, ethers, or esters, the need for defailed information on their combustion chemistries is becoming acute. Additional functional groups in the fuel molecule lead to a larger number of possible structural isomers. The influence of the chemical structure of the fuel molecule... [Pg.10]

Table 4 shows that the substrates usually involved in the reaction with polydichlorophosphazene belong to the categories of aliphatic or aromatic compounds containing in their own chemical structure free -OH and/or -NH2 functionalities, which can be easily found on the market in great abundance and at cheap prices. [Pg.186]


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See also in sourсe #XX -- [ Pg.591 ]




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