Initiator based

At the development planning stage, a reservoir mode/will have been constructed and used to determine the optimum method of recovering the hydrocarbons from the reservoir. The criteria for the optimum solution will most likely have been based on profitability and safety. The model Is Initially based upon a limited data set (perhaps a seismic survey, and say five exploration and appraisal wells) and will therefore be an approximation of the true description of the field. As development drilling and production commence, further data is collected and used to update both the geological model (the description of the structure, environment of deposition, diagenesis and fluid distribution) and the reservoir model (the description of the reservoir under dynamic conditions). [Pg.332]

The discovery of a significant number of hypercoordinate carboca-tions ( nonclassical ions), initially based on solvolytic studies and subsequently as observable, stable ions in superacidic media as well as on theoretical calculations, showed that carbon hypercoordination is a general phenomenon in electron-deficient hydrocarbon systems. Some characteristic nonclassical carbocations are the following. [Pg.159]

The synthetic scheme typically involves chain-extending addition of protected mononucleotides to a nucleoside bound covalentiy at the 3 -hydroxyl to an inert siUca-based soHd support, such as controlled pore glass (Fig. 11). The initial base-protected 5 -O-dimethoxytrityl (DMT) deoxynucleoside is linked to the soHd support via the reaction of a siUca-bound amino-silane and the -nitrophenylester of the 3 -succinylated nucleoside, yielding a 3 -terminal nucleoside attached to the soHd support (1) (Fig. 11). Chain elongation requites the removal of the 5 -DMT protecting group. [Pg.257]

The goal was identification of a complete list of initiators based on the evid accumulated... [Pg.412]

The Limerick analysis accounted for a revised list of incident Initiators based on the Limerick plant design and a more detailed analytical modeling of event sequences following each incident initiator. Plant-design-specific and site-specific data were also included in the analysis of the Limerick Mark II containment and in the meterology and demography imput to the evaluation of incident consequences. [Pg.120]

The first use of sterically hindered hexasubstituted ethanes [e.g. 33] as initiators of polymerization was reported by Bledzki et al.77,78 The use of related initiators based on silylatcd pinacols [e.g. 34, 35] has been reported by Crivcllo et a/.,7l>82 jjan( os et ai i anOther initiators of this class include 36 fi X/ and 37.The rates of decomposition of hexasubstituted ethanes and the derived macroinitiators are known to vary according to the degree of steric... [Pg.467]

Benzoxazine, an heterocycle present as structural subunit in many naturally occurring and synthetic bioactive compounds, was prepared under microwave irradiation from a mixture of 2-aminophenol 218 and an a-bromoester 219 (Scheme 80). The reaction proceeded through an initial base-catalyzed alkylation of the phenoUc OH followed by spontaneous amidation. Yields from 44 to 78% were reported for 17 different benzoxazines 220 [ 141]. [Pg.253]

The underlying cause of anemia (e.g., blood loss iron, folic acid, or vitamin B12 deficiency or chronic disease) must be determined and used to guide therapy. As discussed previously, patients should be evaluated initially based on laboratory parameters to determine the etiology of the anemia (see Fig. 63-3). Subsequently, the appropriate pharmacologic treatment should be initiated based on the cause of anemia. [Pg.980]

Treatment is typically initiated based on symptoms, rather than on microscopic evaluation. Since several species can cause tinea infections, the choice of antifungal agent is not always clear. For infections accompanied by inflammation, combination therapy with a topical steroid can be considered. [Pg.1207]

Tables I-IV contain results as a function of initial base, presence or absence of an added PTC, organometallin reactant and molar ratio of reactants. On a strictly molar ratio of reactant sites basis, the balancing of net quantity of reactants should occur at an organcmetallic/dextran molar ratio of 3 2. The present studies are consistent with earlier studies that showed the maximums occurring away frem this 3 2 ratio. The values cited in Table V for reactant muximums should be considered only as general. Results contained in Table I will be utilized to illustrate how the parameters of percentage yield and position of the maximum of precentage yield as reactant molar ratio is varied might be employed to indicate if the added PTC...

A radical initiator based on the oxidation adduct of an alkyl-9-BBN (47) has been utilized to produce poly(methylmethacrylate) (48) (Fig. 31) from methylmethacrylate monomer by a living anionic polymerization route that does not require the mediation of a metal catalyst. The relatively broad molecular weight distribution (PDI = (MJM ) 2.5) compared with those in living anionic polymerization cases was attributed to the slow initiation of the polymerization.69 A similar radical polymerization route aided by 47 was utilized in the synthesis of functionalized syndiotactic polystyrene (PS) polymers by the copolymerization of styrene.70 The borane groups in the functionalized syndiotactic polystyrenes were transformed into free-radical initiators for the in situ free-radical graft polymerization to prepare s-PS-g-PMMA graft copolymers. [Pg.41]

Pharmaceutical drug development of small molecules is initially based on the selection of candidate targets - mainly enzymes, receptors or circulating proteins that are currently targeted by 45, 28 and 11% of marketed compounds, respec-... [Pg.73]

Treatment of (5,5)-/>/.v(2-hydroxypropyl)phcnylphosphine oxide with initially base followed by Cl(CH2)20(CH2)20Tf gave the dichloride intermediate, which with base and either catechol or tosyl amine in DMF and elevated (150 °C) temperatures generated the macrocyclic phosphane oxide 35 in 15% yield or the l-phospha-10-aza-18-crown-6-ether in 44% yield <06EJOC154>. [Pg.475]

Studies of chemical reactivity in self-assembling colloids were initially based on reactions in aqueous micelles, but recently reactivity has been examined in other colloidal systems such as microemulsions and synthetic vesicles (Mackay, 1981 Fendler, 1982 O Connor et al., 1982, 1984 Cuccovia et al. 1982b). Some hydrophobic trialkylammonium salts, which are phase-... [Pg.221]

To explore the validity of the ring formation strategy, we drew up plans and carried out an enantioselective synthesis of diene 77 (Scheme 19). Initially, based on previous studies on similar medium- and large-ring syntheses, we surmised that elevated temperatures would be necessary for effective macrocycliza-... [Pg.135]

Many studies on side-chain modifications in PF were initially based on the idea of excimer formation, resulting in the green emission during LED operation or in solid-state PL on annealing PF films. This resulted in several proposed strategies for the design of fluorene side-chain homopolymers, where bulky substituents at position 9 of the fluorene moiety should sterically prevent (hinder) interchain interaction and thus improve the stability of blue emission. [Pg.129]

Uniaxial viscosity, 21 718 Unicomponent metathesis initiators based on early transition metals,... [Pg.983]

A diagram of a typical run is given in figure 2 which shows the power generated by mixing of magnesium chloride with water at 200°C. In this calorimeter a heat of dilution takes 30 minutes and from an initial base line it takes about 15 minutes for the calorimeter to reach a steady state. The sensitivity of this calorimeter was equivalent to being able to detect a 2 X 10 4k... [Pg.571]

Although the most frequently used nomenclature for AHLs was initially based on a 3-5 letter codes based on names e.g. BHL for N-butyryl-L-homo-serine lactone, OHHL for AT-(3-oxohexanoyl)-L-homoserine lactone or OdDHL for N-(3-oxododecanoyl)-L-homoserine lactone, the rapid expansion in the range of AHL molecules discovered has led to changes in this nomenclature. Currently, the accepted abbreviations are a structure-based short-hand notations e.g. C4-HSL for N-butyryl-L-homoserine lactone, 3-oxo-C6-HSL (or 30,C6-HSL) for AT-(3-oxohexanoyl)-L-homoserine lactone or 3-hydroxy-C12-HSL (or 30H,C12-HSL) for N-(3-hydroxydodecanoyl)-L-homoserine lactone. [Pg.298]

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