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Systems resulting

Localized erosion-corrosion caused by turbulence or impinging flow at certain points of the surface. In the majority of cases of impingement attack, a geometrical feature of the system results in turbulence at one or more parts of the surface. [Pg.2733]

When polymers or other water-soluble substances are present in the sample, it is advantageous to add a small amount of chloroform to the initial reaction mixture after the subsequent addition of water, a two-phase system results which may be titrated in the usual way to a starch end point or by observing the disappearance of the iodine colour in the chloroform layer. [Pg.808]

The vastly increased acidity of superacidic systems resulted in the significant new field of superacid chemistry. I began to ask myself whether a similar but more general approach could be used to produce electrophiles of greatly enhanced electron deficiency and thus reactivity. Over the years, there were a number of unexpected results in my own research work, as well as some previously unexplained observations buried in the literature, that seemed worth pursuing. [Pg.189]

In general, the sensitivity of FIA is less than that for conventional methods of analysis for two principal reasons. First, as with chemical kinetic methods, measurements in FIA are made under nonequilibrium conditions when the signal has yet to reach its maximum value. Second, dispersion of the sample as it progresses through the system results in its dilution. As discussed earlier, however, the variables that influence sensitivity are known. As a result the FIA manifold can be designed to optimize the sensitivity of the analysis. [Pg.658]

A viable electrocatalyst operating with minimal polarization for the direct electrochemical oxidation of methanol at low temperature would strongly enhance the competitive position of fuel ceU systems for transportation appHcations. Fuel ceUs that directiy oxidize CH OH would eliminate the need for an external reformer in fuel ceU systems resulting in a less complex, more lightweight system occupying less volume and having lower cost. Improvement in the performance of PFFCs for transportation appHcations, which operate close to ambient temperatures and utilize steam-reformed CH OH, would be a more CO-tolerant anode electrocatalyst. Such an electrocatalyst would reduce the need to pretreat the steam-reformed CH OH to lower the CO content in the anode fuel gas. Platinum—mthenium alloys show encouraging performance for the direct oxidation of methanol. [Pg.586]

The si2e of the vegetable tanning molecules and the coUoidal nature of the system result in the fixation in the hide of filling materials. The filling action is essentially an impregnation of the hide to form a dense firm leather. These properties are gready desired in sole and mechanical leathers. [Pg.86]

Spills should be picked up before flushing thoroughly with water and neutralizing with soda ash or lime. The introduction of aluminum chloride into any drainage system results in the reduction of effluent pH, which can be adjusted using caustic soda or lime (11). [Pg.148]

This system results in a 18% solids by weight dispersion. [Pg.85]

The highly polar nature of the TGMDA—DDS system results in high moisture absorption. The plasticization of epoxy matrices by absorbed water and its effect on composite properties have been well documented. As can be seen from Table 4, the TGMDA system can absorb as much as 6.5% (by weight) water (4). This absorbed water results in a dramatic drop in both the glass transition temperature and hot—wet flexural modulus (4—6). [Pg.21]

Many waste-rock or overburden disposal systems result ia compacted dumps having uncontrolled distribution of fines. In such dumps, solution distribution is poor and there is Htde oxygen for reaction with the sulfides. Methods for managing these dumps to maximize copper recovery have been actively pursued. [Pg.206]

Halobutyl Cures. Halogenated butyls cure faster in sulfur-accelerator systems than butyl bromobutyl is generally faster than chlorobutyl. Zinc oxide-based cure systems result in C—C bonds formed by alkylation through dehydrohalogenation of the halobutyl to form a zinc chloride catalyst (94,95). Cure rate is increased by stearic acid, but there is a competitive reaction of substitution at the halogen site. Because of this, stearic acid can reduce the overall state of cure (number of cross-links). Water is a strong retarder because it forms complexes with the reactive intermediates. Amine cure may be represented as follows ... [Pg.486]

As shown in Scheme 2, two heteroatom-carbon bonds are constructed in such a way that one component provides both heteroatoms for the resultant heterocycle. By variation of X and Z entry is readily obtained into thiazoles, oxazoles, imidazoles, etc. and by the use of the appropriate oxidation level in the carbonyl-containing component, further oxidized derivatives of these ring systems result. These processes are analogous to those utilized in the formation of five-membered heterocycles containing one heteroatom, involving cyclocondensation utilizing enols, enamines, etc. [Pg.118]

Benzisoxazole and its simple alkyl derivatives are liquids with b.p. s of 84°C/11 mmHg for the unsubstituted system, 92.5°C/11 mmHg for the 3-methyl compound, and 117 °C/11 mmHg for the 4,6-dimethylbenzisoxazole. 2,1-Benzisoxazole is also a liquid, b.p. 94.4-94.5 °C/11 mmHg, and its 3-methyl derivative has a b.p. of 115.5-116 °C/11 mmHg. Introduction of a 3-phenyl substituent in both systems results in crystallinity, with m.p. s of 83-84 °C and 52-53 °C, respectively. Polar substituents, as anticipated, also impart crystallinity to these systems. [Pg.9]

Component 1 is the solute, while component 2 is water. The molar volume of the solute in mVkmole is at the solute normal boiling point, while the viscosity of water in Pa sec is at the temperature of the system resulting in a diffusivity in mVsec. The average error is about 9 percent when tested on 36 experimental systems. [Pg.416]

Decreased liquid-liquid interfacial tension (when compared with a gas-liquid system) results in higher liquid-liquid interfacial areas, which favor solid-particle droplet collisions. [Pg.2015]

FIA). Figure 25-39 presents a schematic of the sampling system. Results are reported as volume concentration equivalents of the cah-bration gas or as carbon equivalents. [Pg.2205]

Most cracking problems in cooling water systems result from one of two distinct cracking mechanisms stress-corrosion cracking (SCC) or corrosion fatigue. [Pg.199]

Note that low carbon or stabilized grades of stainless steel do not possess intrinsically greater corrosion resistance than their unadjusted counterparts. Their sole value in typical cooling water systems results from their resistance to sensitization and potential weld decay that can result when the metals are welded. It is therefore not economically justifiable to specify low carbon or stabilized grades of stainless steel for typical cooling water system components that are not to be welded. [Pg.342]

Inadvertent or uncontrolled opening of high pressure utility system resulting in vessel... [Pg.54]

In the U.S., the result will be in inches for the metric system the results will be in meters. The relationship to convert between the two numbering system results is... [Pg.40]

The meaning of the word aromaticity has evolved as understanding of the special properties of benzene and other aromatic molecules has deepened. Originally, aromaticity was associated with a special chemical reactivity. The aromatic hydrocarbons were considered to be those unsaturated systems that underwent substitution reactions in preference to addition. Later, the idea of special stability became more important. Benzene can be shown to be much lower in enthalpy than predicted by summation of the normal bond energies for the C=C, C—C, and C—H bonds in the Kekule representation of benzene. Aromaticity is now generally associated with this property of special stability of certain completely conjugated cyclic molecules. A major contribution to the stability of aromatic systems results from the delocalization of electrons in these molecules. [Pg.509]

Addition cure silicones can be delivered from solvent, waterborne emulsions, or 100% solids systems. The solvent free versions employ base polymers of intermediate molecular weight to achieve processable viscosity. These base polymers can have reactive moieties in terminal and/or pendant positions. These lower molecular weight, more functional systems result in a tighter crosslink network which feels rubbery to the hand. Low amounts of high molecular weight additives are included in some formulations to provide a more slippery feel [51,52]. [Pg.544]


See other pages where Systems resulting is mentioned: [Pg.2744]    [Pg.338]    [Pg.159]    [Pg.98]    [Pg.239]    [Pg.383]    [Pg.353]    [Pg.178]    [Pg.244]    [Pg.285]    [Pg.151]    [Pg.379]    [Pg.514]    [Pg.45]    [Pg.269]    [Pg.223]    [Pg.451]    [Pg.187]    [Pg.190]    [Pg.345]    [Pg.349]    [Pg.231]    [Pg.2493]    [Pg.33]    [Pg.349]    [Pg.452]    [Pg.224]    [Pg.686]    [Pg.720]   
See also in sourсe #XX -- [ Pg.8 , Pg.27 ]

See also in sourсe #XX -- [ Pg.8 , Pg.27 ]




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