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Additives Additives

Impact of additive/additive, additive/solvent interaction... [Pg.177]

The level of injector fouling is most often illustrated in terms of residual flow (RF) expressed as a percentage of the flow under new conditions for a given needle lift. An RF on the order of 20% for a lift of 0.1 mm is a good compromise. This level may not be achieved with certain aromatic or naphthenic diesel fuels. The best recourse is then detergent additive addition. [Pg.247]

Protonation of the carbonyl oxygen activates the carbonyl group toward nucleophilic addition Addition of an alcohol gives a tetrahedral inter mediate (shown m the box m the preceding equation) which has the capacity to revert to starting materials or to undergo dehydration to yield an ester... [Pg.823]

Stabilizers, pigments, and other additives are milled in spinning solvent, normally along with small amounts of the urethane polymer to improve dispersion stabiUty this dispersion is then blended to the desired concentration with polymer solution after chain extension. Most producers combine prepolymerization, chain extension, and additive addition and blending into a single integrated continuous production line. [Pg.307]

Antiicing Additives. Additives to control icing are rarely used in the United States because vehicle design changes have made icing problems almost nonexistent. [Pg.186]

Factors such as reaction temperature, excess of oxygen, water addition, addition of other minor reactants, eg, AlCl to promote the formation of mtile, mixing conditions inside the reactor, and many others influence the quaUty of Ti02 pigment. In general, titanium white pigments produced by the chloride process exhibit better lightness than those produced by the sulfate process. [Pg.9]

Additives. Additives can be iatroduced ia salt preparatioa, polymerizatioa, or the molten polymer stream prior to extmsioa of the fUameats. Additives are used to alter the basic characteristics and performance of the fiber and can be classified by function. [Pg.256]

Additive Additive b , quantity, wt /o Reflux time, h Sulfolane recovery, wt % Remarks... [Pg.68]

Copper anodes for use in acid copper plating solutions preferably contain a small amount of phosphoms [7723-14-0] usually 0.03—0.04 wt %, which retards chemical dissolution of the copper and thus the subsequent copper build-up. Typically, acid copper plating solutions increase in copper and require periodic dilution. Additionally, additives for brightening acid copper baths tend to last longer in plating tanks using phosphorized copper anodes. In cyanide copper solutions, phosphorized copper anodes should not be used. [Pg.147]

Addition. Addition reactions of ethylene have considerable importance and lead to the production of ethylene dichloride, ethylene dibromide, and ethyl chloride by halogenation—hydrohalogenation ethylbenzene, ethyltoluene, and aluminum alkyls by alkylation a-olefms by oligomerization ethanol by hydration and propionaldehyde by hydroformylation. [Pg.433]

Use nonsplash addition methods for liquids (e.g., subsurface addition, addition along the wall, etc.)... [Pg.85]

Rubber base adhesives develop strength faster than most other polymeric types. Fig. 1 [3J shows the differences in the development of peel strength for several rubber polymers (without additional additives, except an antioxidant). Natural... [Pg.576]

Zusatz-. additional, supplementary, auxiliary admixed, added additive, -element, n. (Metal.) alloying element, -feld, n, addi tional field, supplementary field, -gerat, n. Supplementary apparatus, attachment, -glied, n. additional term, supplementary term, -lack, m. blending varnish, zusatzlich, a. additional additive supplementary, auxiliary. [Pg.538]

Sulfonyl bromides and iodides react similarly217-218-225 copper-salt catalysis in these cases facilitates the additions but is not absolutely necessary however, it influences the stereochemistry of the additions. Addition of sulfonyl iodides226 as well as the uncatalyzed thermal addition of sulfonyl bromides227 to alkynes leads to an exclusive trans-addition, whereas CuBr2 catalysis in the latter case causes the formation of cis-addition products to some extent (11 16%) correspondingly, copper-salt catalysis in sulfonyl chloride additions to alkynes leads to the formation of a mixture of Z,E-isomers228-229 (equation 40). [Pg.189]

The ease of reduction of the Pu 4+ ions apparently can be affected by inclusion in the glass of additional additives. Whereas the addition of Ti02 apparently does not affect in-situ reduction, the addition of CaO, ZnO, or B2O3 appreciably accelerated reduction of the Pu 4+ ions. This effect is demonstrated with 4f core level spectra of glasses F, G, H, and I shown in Fig. 3. Each sample was subjected to the same X-ray exposure, i.e., the same number of scans at the same flux. [Pg.153]

Dipoiar Addition (Addition of Oxygen, Nitrogen, Carbon)... [Pg.1059]

The enantioselective 1,4-addition addition of organometaUic reagents to a,p-unsaturated carbonyl compounds, the so-called Michael reaction, provides a powerful method for the synthesis of optically active compounds by carbon-carbon bond formation [129]. Therefore, symmetrical and unsymmetrical MiniPHOS phosphines were used for in situ preparation of copper-catalysts, and employed in an optimization study on Cu(I)-catalyzed Michael reactions of di-ethylzinc to a, -unsaturated ketones (Scheme 31) [29,30]. In most cases, complete conversion and good enantioselectivity were obtained and no 1,2-addition product was detected, showing complete regioselectivity. Of interest, the enantioselectivity observed using Cu(I) directly in place of Cu(II) allowed enhanced enantioselectivity, implying that the chiral environment of the Cu(I) complex produced by in situ reduction of Cu(II) may be less selective than the one with preformed Cu(I). [Pg.36]

The DKR processes for secondary alcohols and primary amines can be slightly modified for applications in the asymmetric transformations of ketones, enol esters, and ketoximes. The key point here is that racemization catalysts used in the DKR can also catalyze the hydrogenation of ketones, enol esters, and ketoximes. Thus, the DKR procedures need a reducing agent as additional additive to enable asymmetric transformations. [Pg.73]

Bioventing technology was developed by the U.S. EPA Risk Reduction Engineering Laboratory to treat soil contaminated by numerous industrial wastes, which is subjected to aerobic microbial degradation, especially to promote the degradation of polycyclic aromatic hydrocarbons.65 It uses a series of air injection probes, each of which is attached to a low-pressure air pump. The air pump operates at extremely low pressures to allow the inflow of oxygen without volatilization of contaminants. Additional additives such as ozone or nutrients may also be supplied to stimulate microbial growth.77... [Pg.739]

One property of drilling fluids that has received only minimal attention in the past is corrosiveness imparted by various additives. Additives improve the requisite properties of well fluid substantially and, hence, increase in corrosiveness is usually ignored. [Pg.631]


See other pages where Additives Additives is mentioned: [Pg.221]    [Pg.224]    [Pg.95]    [Pg.554]    [Pg.164]    [Pg.174]    [Pg.233]    [Pg.234]    [Pg.415]    [Pg.379]    [Pg.164]    [Pg.171]    [Pg.204]    [Pg.15]    [Pg.538]    [Pg.150]    [Pg.241]    [Pg.244]    [Pg.373]    [Pg.4]    [Pg.293]    [Pg.396]    [Pg.2]    [Pg.3]    [Pg.277]    [Pg.635]    [Pg.863]   


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