Dual attraction

In some contexts the dual attractions of likes to likes and of opposites to opposites appear to be genuinely different phenomena that cannot be reduced to the same underlying causal structure. If the contraries are complementary to each other, their union may form the basis of organic solidarity in Durkheim s sense. (Conversely, mechanical solidarity is based on similarity.) Some people may seek spouses who are different from themselves because they sense that the other can provide something they need but do not have themselves. A mercurial person, for instance, may seek or welcome the stability provided by a more even-tempered partner. Others may seek the comforts of familiarity and the benefits of being able to take lots of things for granted. These mechanisms are very unlike the choice of a spouse who appears attractively mysterious because he or she is optimally different from oneself. 

Chemically active These filters are similar in design to the non-active depth units but the filtering media used are so chosen that contaminants adhere by chemical attraction. Thus there is a dual action, mechanical and chemical. The materials used include various activated clays. Fuller s earth, charcoal and chemically treated paper. Their cleansing action is much more thorough than that of the purely mechanical devices, for they are capable of removing matter actually in solution in the oil. 

The most important area for packed column use involves modified mobile phases (MPs). Consequently, pSFC needs detection systems in which the MP modifier and possible additive(s) do not interfere, and in which detection of low or non-UV-absorbing molecules is possible in combination with pressure/modifier gradients. The disadvantage of adding even small amounts of modifier is that FID can no longer be used as a detector. In the presence of polar modifiers in pSFC the detection systems are restricted basically to spectroscopic detection, namely UVD, LSD, MSD (using PB and TSP interfaces as in LC). ELSD can substitute FID and covers the quasi-universal detection mode, while NPD and ECD cover the specific detection mode in pSFC on a routine basis. As ELSD detects non-UV absorbing molecules dual detection with UV is an attractive option. 

Excited-state intramolecular proton transfer (ESIPT) exhibits different regularities [49, 50]. Commonly, this is a very fast and practically irreversible reaction proceeding along the H-bonds preexisting in the ground state. Therefore, only the reaction product band is seen in fluorescence spectra. Such cases are not interesting for designing the fluorescence reporters. The more attractive dual emission is... 

Triple reuptake inhibitors (TRIs), which inhibit reuptake at all three transporters, have attracted considerable interest in recent years [77]. The involvement of dopamine reuptake in the etiology of depression and other CNS disorders has been recognized [29,30]. As a result, TRIs have been proposed to offer a faster onset of action and improved efficacy for depression over currently prescribed single or dual action monoamine reuptake inhibitors. Historically, the mesocorticolimbic dopamine pathway is thought to mediate the anhedonia and lack of motivation observed in depressed patients [78,79]. In addition, methylphenidate, both immediate release and extended release formula, has been found to be effective as an augmenting agent in treatment-resistant depression [4]. Furthermore, clinical studies using the combination of bupropion and an SSRI or SNRI have showed improved efficacy for the treatment of MDD in patients refractory to the treatment with SSRIs, SNRIs, or bupropion alone [5,80,81]. 

The use of water-miscible organic solvent-water mixtures is a particularly attractive method for use with cofactor-dependent enzymes due to its simphcity. The high water content can allow dissolution of both enzyme and cofactor, whilst the water-miscible solvent can provide a dual role in both substrate dissolution and as a cosubstrate for cofactor recycling (substrate-coupled cofactor recycling).The asymmetric reduction of a ketone intermediate of montelukast using an engineered ADH in the presence of 50 % v/v isopropanol offers a powerful demonstration of this methodology (Scheme 1.55). 

Since the start of modern interpenetrating polymer network (IPN) research in the late sixties, the features of their two-phased morphologies, such as the size, shape, and dual phase continuity have been a central subject. Research in the 1970 s focused on the effect of chemical and physical properties on the morphology, as well as the development of new synthetic techniques. More recently, studies on the detailed processes of domain formation with the aid of new neutron scattering techniques and phase diagram concepts has attracted much attention. The best evidence points to the development first of domains via a nucleation and growth mechanism, followed by a modified spinodal decomposition mechanism. This paper will review recent morphological studies on IPN s and related materials. 

Domino reactions attract significant attention due to their ability to allow for multi-step operations in one pot. Two classes of domino transformations are known for the PK reaction. The first involves the use of a dual-catalyst system, while the second uses a single catalyst with modification of the reaction parameters to control reactivity. 

Silica-magnesia matrices have not yet been properly evaluated as an RCC catalyst matrix. However, such a matrix in conjunction with stabilized zeolite might provide an attractive matrix with a Kaolin-enhanced dual pore structure. Silica-magnesia matrices are notorious for their poor regeneration characteristics. When prepared by the dual pore Kaolin-enhanced method, they might be easier to regenerate and, thereby, open up a new family of residuum catalysts. Such catalysts have not yet been explored. 

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