0-effect elimination

Mesitylene. One of the principal derivatives of mesitylene is the sterically hindered phenol of the structure shown in Figure 4. Its trade name is Ethanox 330 and it is produced by Albemade Corporation (formedy Ethyl Corporation) (31). Ethanox 330 is an important noncoloring antioxidant and thermal stabilizer for plastics, adhesives, rubber, and waxes (qv) (32,33) (see Antioxidants). The oral toxicity of Antioxidant 330 is extremely low (oral 1D. in rats > 15 g/kg) since its large size, Cc4H7 0, effectively eliminates absorption from the gastrointestinal tract. [Pg.509]

Antibiotic and Antimicrobial Drugs. The antimicrobial agents (119) flumequiae (160) and (161), and methylflumequiae (S-25930) (162) and (163) effectively eliminate a number of microbial pathogens via inhibition of the topoisomerase II enzyme of c-DNA containing bacteria (120) (see... [Pg.256]

In MacPherson vs Buick Motor Company, Justice Cardozo put an end to the temporizing and effectively eliminated privity as an obstacle to recovery against negligent manufacturers (5) ... [Pg.96]

Not only is TCDO a potent therapeutic agent in acute radiation syndrome, but treatment using TCDO from days 4—11 after TBI increases the survival rate in rats for up to one year, protects against the development of late GI ulcers, and also reduces the development of y-ray-induced leukemias and malignant epitheHal tumors, but not sarcomas (202). The anticarcinogenic effect of TCDO maybe related to the inhibition of PGs, which promote carcinogenesis, or to immunostimulation, which may result in a more effective elimination of malignant cells. [Pg.496]

For thermodynamic treatmeat of surface phenomena, the thickness of the bouadary regioas can often be ignored or their effect eliminated by selection of a convenient location for the iaterface The Hquid—Hquid iaterface, (Fig- lb) is similarly associated with iaterfacial regioas, R and Rg,... [Pg.234]

Acceptance of a color recommendation made by the coatings suppHer effectively eliminates the time and cost involved in an initial color match and ensures selection of a pigment combination appropriate to the coating use. If, however, a coatings user provides a sample or standard for a color match, formulators need the foUowing information. [Pg.344]

For catalytic investigations, the rotating basket or fixed basket with internal recirciilation are the standard devices nowadays, usually more convenient and less expensive than equipment with external recirculation. In the fixed basket type, an internal recirculation rate of 10 to 15 or so times the feed rate effectively eliminates external diffusional resistance, and temperature gradients. A unit holding 50 cm (3.05 in ) of catalyst can operate up to 800 K (1440 R) and 50 bar (725 psi). [Pg.708]

Combining the practice of preventive maintenance and total quality control and total employee involvement results in an innovative system for equipment maintenance that optimizes effectiveness, eliminates breakdowns, and promotes autonomous operator maintenance through day-to-day activities. This concept known as Total Productive Maintenance (TPM) was conceived by Seiichi Nakajima and is well-documented in his book Introduction of TPM and is highly recommended reading for all involved in the maintenance area. [Pg.723]

Compounds such as hydrogen sulfide and cyanides are the most common metal surface poisoners occurring in process units subject to aqueous-phase hydrogen attack. In many process units, these compounds can be effectively eliminated and hydrogen diffusion stopped by adding ammonium polysulfides and oxygen to the process streams which converts the compounds to polysulfides and thiocyanates, provided the pH is kept on the alkaline side. [Pg.258]

Effective elimination of emission sources through the selection of the best process technology or effective control of emissions from sources that cannot be avoided... [Pg.401]

To effectively eliminate these small particles and fulfill official requirements, finer filters are needed, and the requirement for filtering of outdoor air, recycled air, or exhausted air is increasing. With an F7 (EU7) filter, good separation of small particles is achieved. [Pg.681]

It has been claimed that the elimination of tosylates of 3a-alcohols in 5jS-series gives 3-oleflns with high selectivity. However, the homogeneity of these products is questionable, in view of recent findings concerning the ehmination of 3-chloro compounds (see below) and Fieser s results with the elimination of methyl lithocholate tosylate (ref. 232, cf. ref. 233). Neutral alumina may also be used to effect elimination of tosylates of 3j5-alcohols if the alumina is pretreated with potassium hydroxide the inverted alcohol is the predominant product. [Pg.329]

Iodine azide, on the other hand, forms pure adducts with A -, A - and A -steroids by a mechanism analogous to that proposed for iodine isocyanate additions. Reduction of such adducts can lead to aziridines. However, most reducing agents effect elimination of the elements of iodine azide from the /mwj -diaxial adducts of the A - and A -olefins rather than reduction of the azide function to the iodo amine. Thus, this sequence appears to be of little value for the synthesis of A-, B- or C-ring aziridines. It is worthy to note that based on experience with nonsteroidal systems the application of electrophilic reducing agents such as diborane or lithium aluminum hydride-aluminum chloride may yet prove effective for the desired reduction. Lithium aluminum hydride accomplishes aziridine formation from the A -adducts, Le., 16 -azido-17a-iodoandrostanes (97) in a one-step reaction. The scope of this addition has been considerably enhanced by the recent... [Pg.24]

Compared to the overlap of the undistorted atomic orbitals used in the HL wave function, which is just 5ab. it is seen that the overlap is increased (c is positive), i.e. the orbitals distort so that they overlap better in order to make a bond. Although the distortion is fairly small (a few %) this effectively eliminates the need for including ionic VB terms. When c is variationally optimized, the MO-CI, VB-HL and VB-CF wave functions (eqs. (7.4), (7.7) and (7.8)) are all completely equivalent. The MO approach incorporates the flexibility in terms of an excited determinant, the VB-FIL in terms of ionic structures, and the VB-CF in terms of distorted atomic orbitals. [Pg.197]

Drafts, condensation on windows, ice damming, excessive noise from outdoors or equipment operation, and rooms that are cold in winter and hot in summer will diminish comfort in a home. Air-sealed construction, improved insulation, high-performance windows, right-sized, efficient hcating/cooling distribution systems, and mechanical ventilation commonly found in energy-efficient homes all work together to effectively eliminate these problems. [Pg.209]

Parent polyfthicnylene vinylene) has also been synthesized by an aldol precursor route [122]. In this method, 5-methyl-2-thiophenecarbaldehyde 76 is treated with a base and the monomer polymerizes yielding a precursor 77 which is soluble in water. Thermal treatment in an acidic solution at 80 nC yields the fully conjugated material. Alternatively, the solid polymer may be healed to 280 C to effect elimination of water. Fully conjugated material exhibits low conductivity (10 8 S cm"1) in its pristine stale. [Pg.343]

Otera and coworkers have published several reaction sequences160-163 that effect eliminations of phenylsulphonyl groups under basic conditions. In one sequence160, a-methoxy phenyl sulphones are treated with potassium t-butoxide in THF to give fairly good yields of vinyl ethers, by the elimination of phenylsulphinate anion, as shown in equation (67). [Pg.953]

While the pzc of Hg in F solution has not changed by more than 1 mV for over 70 years, marginal variations are visible for Ga, Tl, In, Cd, Bi, Sn, and Sb that are related to electrolyte effects (weak specific adsorption or disturbance of the adsorbed water layer, as for Ga).847 Important variations can be seen, on the other hand, for polycrystalline Ag, Zn, Ni, Fe, and Cu. For all these metals a drop of the pzc to much more negative values has been recorded this is evidently related to an improvement in the preparation of the surface with more effective elimination of surface oxides. All these metals, with the exception of Ag, are naturally sensitive to atmospheric oxygen. Values of pzc for single-crystal faces first appeared in a 1974 compilation,23 in particular for the three main faces of Ag and for Au (110). Values for a number of other metals were reported in 1986.25 However, for sd-metals, an exhaustive, specific compilation of available experimental data was given by Hamelin etal. in 1983.24... [Pg.152]

Effect of Solvent on Elimination versus Substitution. Increasing polarity of solvent favors Sn2 reactions at the expense of E2. In the classical example, alcoholic KOH is used to effect elimination, while the more polar aqueous KOH is used for substitution. Charge-dispersal discussions, similar to those on page 450, only partially explain this. In most solvents, SnI reactions are favored over El. The El reactions compete best in polar solvents that are poor nucleophiles, especially dipolar aprotic solvents" A study made in the gas phase, where there is no solvent, has shown that when 1-bromopropane reacts with MeO only elimination takes place no substitution even with this primary substrate." ... [Pg.1322]

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