Saturated bonds

The largest series is that of the alkanes or paraffins, which are open chain molecules with saturated bonds, and have the general formula C H2n+2-... 

Migration of a hydride ligand from Pd to a coordinated alkene (insertion of alkene) to form an alkyl ligand (alkylpalladium complex) (12) is a typical example of the a, /(-insertion of alkenes. In addition, many other un.saturated bonds such as in conjugated dienes, alkynes, CO2, and carbonyl groups, undergo the q, /(-insertion to Pd-X cr-bonds. The insertion of an internal alkyne to the Pd—C bond to form 13 can be understood as the c -carbopa-lladation of the alkyne. The insertion of butadiene into a Ph—Pd bond leads to the rr-allylpalladium complex 14. The insertion is usually highly stereospecific. 

Saturated absorption Saturated brine Saturation Saturation bonding Saturation magnetization Sauerkraut Sauflon Sauflon PW S. aureus... 

The magnitude of the induced dipole moment depends on the electric field strength in accord with the relationship = nT, where ]1 is the induced dipole moment, F is the electric field strength, and the constant a is caHed the polarizabHity of the molecule. The polarizabHity is related to the dielectric constant of the substance. Group-contribution methods (2) can be used to estimate the polarizabHity from knowledge of the number of each type of bond within the molecule, eg, the polarizabHity of an unsaturated bond is greater than that of a saturated bond. 

Saturation bonding is used in conjunction with processes that require rapid binder addition, such as card-bond systems, and for fabfic appHcations that require strength and maximum fiber encapsulation, such as carrier fabrics. Eiber encapsulation is achieved by totally immersing the web in a binder... 

Nonstabilized foams are referred to as froths froth-bonded fabrics are similar in properties to some saturation-bonded nonwovens. Typical foams used as nonwoven binder solutions have a consistency similar to shaving cream. AppHcation methods include knife-edge layering onto a horizontal web surface followed by vacuum penetration, and saturation and penetration of a vertical web surface using a horizontal-nip pad. Drying and curing is carried out in ovens, dmm dryers, or steam cans. 

In a class of reahstic lattice models, hydrocarbon chains are placed on a diamond lattice in order to imitate the zigzag structure of the carbon backbones and the trans and gauche bonds. Such models have been used early on to study micelle structures [104], monolayers [105], and bilayers [106]. Levine and coworkers have introduced an even more sophisticated model, which allows one to consider unsaturated C=C bonds and stiffer molecules such as cholesterol a monomer occupies several lattice sites on a cubic lattice, the saturated bonds between monomers are taken from a given set of allowed bonds with length /5, and torsional potentials are introduced to distinguish between trans and "gauche conformations [107,108]. 

Allylic and benzylic C—X bonds are about 50 kj/mol (12 kcal/mol) weaker than the corresponding saturated bonds and are therefore more easily broken. 

Most radicals located on saturated bonds are jt-radicals with a planar configuration and may be depicted with the free spin located in a p-orbital (1). Because such radical centers are achiral, stereochemical integrity is lost during radical formation, A new configuration will be assumed (or a previous configuration resumed) only upon reaction. Stereoselectivity in radical reactions is therefore dependent on the environment and on remote substituents. 

The analysis of published data on reactions of ozone with low molecular hydrocarbons shows that double bonds react with ozone more quickly than saturated bonds (12). Ozone reacts with saturated hydrocarbons in reactions in which hydrogen abstraction s followed by re-hydridization of the carbon atom form sp to sp state (43,44) ... 

Low viscosity (low concentration systems). Radicals are species that normally have short lifetimes (10 2s to 10 s). In the course of a chain growth mechanism (see Figure 18) they terminate by finding a second non-paired electron to build a chemical link made of an electron pair. This requires that two radicals meet, either to pair their electrons and combine (addition) or to exchange a hydrogen, leading to the formation of one saturated bond and one double bond (disproportionation). 

Given that ET through proteins is fundamental to many biological processes and that H-bonds are prevalent in proteins, it is important to determine how efficiently ET can be mediated by H-bonds. Of the several studies which have been reported, that by Therien is of particular interest since it provides a comparative study of ET mediated by saturated bonds and by H-bonds.1341... 

Saturable dye absorber, 14 677 Saturated aqueous salt solution, 9 34 Saturated calomel electrode (SCE), 9 571 Saturated fatty acids, 10 829, 830 Saturated hydrocarbons adsorbent affinity, 1 674 adsorption by zeolites, 1 624 fluorine reactivity with, 11 831 isomerization of, 12 172—173 Saturated polyester resins, based on trimethylpentanediol, 12 673 Saturated polyesters, 10 7 Saturated synthetic rubber, 10 705 Saturation and coating processes, 10 12-13 Saturation bonding, 17 509-510 Saturation color, 19 262 Saturation concentration, 15 677 Saturation index... 

These latter considerations clarify our position on the use of particular models of molecular electronic structure. The electron-pair model is not absolutely preferable to the MO model in all respects, that is the electron-pair model is not to be recommended per se, but is to be preferred in most systems consisting of ground states of saturated bonds. 

A sigma (it) bond is a single (or saturated) bond between two carbon atoms. 

Aliphatic- Straight- or branch-chain organic molecules that have saturated bonds (paraffins), double bonds (olefins), or triple bonds (acetylenes). 

Desaturation of a saturated bond to produce an unsaturated fatty acid (the conversion of -CH2-CH2- to -CH=CH-) is catalysed by enzymes known as acyl-CoA desaturases. 

Alkanes, also called paraffins, are composed of all C-C, saturated bonds and have the general formula C H2n+2. The naming conventions and typical properties of the first... 

Figure 4.8 shows that the individual bonds in four-atom s-valent clusters are unsaturated, taking bond orders that are much less than unity. The two end bonds of the linear chain provide the only exception. This reduction in bond order compared to the isolated dimer is, of course, due to a given spherically symmetric s orbital forming bonds with all its neighbours. However, we will see later in Chapter 7 that the angular character of hybrid orbitals allows some sp-valent solids to exhibit saturated bond behaviour. Thus, the concept of the bond order is important because it not only... 

Thus, there is no a priori reason for saturated bonds to form a more stable structure than unsaturated bonds. Although the individual bond energy is larger, there are fewer neighbours in the open structures with saturated... 

Polymers with saturated bonds, heteroatoms, heterostructures and poly-conjugated ones are available now as photosensitive materials. Really one cannot expect a single mechanism to be reponsible for photoconductivity in so many diverse systems. However, there are a lot of verified factors which permit us to explain the main features of the photoconductive processes in polymers. The status and prospects of the application of polymeric photoconductors as prospective new electronic materials will be also analyzed for various types of photoconductors. 

Polymers with Saturated Bonds in the Backbone Chain... 

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