Multi-step processes

Coupling to a mineral surface requires the presence of active hydroxyls on the substrate. The coupling reaction is a multi-step process that proceeds from a state of physisorption through hydrogen bond formation to actual covalent bond formation through condensation of surface hydroxyls with silanols ... 

Benzoyl chloride reacts with 2-mercaptoethanol in base to give an ester. When the reaction is monitored carefully, the rapid buildup of an intermediate, X , of molecular formula C9H10O2S, is observed. This is slowly transformed into the ester of the same molecular formula. Although ester formation is known to be a multi-step process, X does not correspond to any of the usual intermediates in ester formation. What is going on here ... 

The incorporation of functionality into an ion slated for use in formulation of an ionic liquid is a usually a multi-step process. Consequently, a number of issues must be considered in planning the synthesis of the ion. The first of these is the choice of the cationic core. The core of a TSIL cation may be as simple as a single... 

Sometimes it is difficult to classify a one-pot multi-step process. Thus for the sake of clarity, we think that the more general term multiple reaction is preferable to indicate a one-pot process in which several bonds are formed sequentially, regardless of whether the reaction conditions are changed or not, or whether new reagents are added during the process. 

The integration of newly synthesized viral DNA into the host chromosome is a multi-step process (Anthony 2004 Van Made and Debyser 2005) that relies on the integrity of the last 10-20 base pairs at both ends of the viral cDNA besides a fully functional integrase (see Fig. 1). Initially, integrase recogiuzes the long-terminal repeat (LTR) of the retro-transcribed viral DNA and performs endonucleolytic... 

Phenol is the starting material for numerous intermediates and finished products. About 90% of the worldwide production of phenol is by Hock process (cumene oxidation process) and the rest by toluene oxidation process. Both the commercial processes for phenol production are multi step processes and thereby inherently unclean [1]. Therefore, there is need for a cleaner production method for phenol, which is economically and environmentally viable. There is great interest amongst researchers to develop a new method for the synthesis of phenol in a one step process [2]. Activated carbon materials, which have large surface areas, have been used as adsorbents, catalysts and catalyst supports [3,4], Activated carbons also have favorable hydrophobicity/ hydrophilicity, which make them suitable for the benzene hydroxylation. Transition metals have been widely used as catalytically active materials for the oxidation/hydroxylation of various aromatic compounds. 

Once soil samples have been received and properly logged in by the laboratory, there is a multi-step process required to isolate agrochemical residues from the sample matrix so that sensitive, reproducible analysis can occur. Residue methods for agrochemicals in soil involve the basic steps shown in Figure 8. 

Therefore even though the driving force is much less for the hole transfer from G + to Ptz compared to that from G + to Py, similar kinetics were obtained. This is consistent with the assumption that the hole transfer from G + to Py or Ptz includes a multi-step process between Gs in the G-region that is, the hole transfer from G + to Py or Ptz is not a rate determining step for the observed hole transfer. 

Adsorption and Film Formation. Inhibition of HC1 corrosion by organic compounds is a complicated multi-step process. Nevertheless, the effect of an inhibitor on corrosion of a metal is often treated mathematically with an equilibrium adsorption model for displacement of water (19,20) ... 

The principles of collagen folding differ markedly from other known proteins since single monomers cannot fold. Triple helix folding is a multi-step process involving chain association, registration, nucleation and... 

The north polar region of Mars consists of variously layered sediments, the upper layer consisting of water ice and thus having a high albedo. More detailed pictures ( 30 cm per pixel) were obtained from the High Resolution Imaging Science Experiment (HiRISE) on board the Mars Reconnaissance Orbiter (MRO). The sediment layers in this region are only about 10 cm thick but seem to be covered with a layer of dust. A detailed analysis of the HiRISE pictures of the north pole deposits indicate that complex, multi-step processes must have occurred at the polar icecaps (Herkenhoff et al., 2007). 

Chemical carcinogenesis by polycyclic aromatic hydrocarbons (PAHs) is a multi-step process in which each of the steps must occur if a neoplasm is to develop. Thus, exposure to PAHs alone is not necessarily sufficient for the induction of a tumor. Many of these factors are summarized below and are discussed in various chapters of this volume. Considered here will be those factors influencing the reactions of the metabolically activated forms of the PAHs with DNA and the ways in which adducts may be detected and characterized. 

Figure 1.74 Thiol-containing disulfide reductants reduce disulfide groups through a multi-step process producing a mixed disulfide intermediate.

Conjugations done with SIAB usually proceed by a multi-step process. Because the crosslinker s NHS ester end is its most labile functionality, an amine-containing protein or molecule... 

We call the slowest step in a multi-step process its ratedetermining step, often abbreviated to RDS. The overall (observed) rate of a multi-step reaction is equal to the rate of the ratedetermining reaction. 

A reaction can be thought of as a multi-step process first the reactants approach and then they collide. Only after touching do they react. One of the more useful definitions... 

Construction of the nucleic base via a multi-step process, centered on the monosaccharide structure.104... 

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