Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Compositions from

For liquid-liquid separations, the basic Newton-Raphson iteration for a is converged for equilibrium ratios (K ) determined at the previous composition estimate. (It helps, and costs very little, to converge this iteration quite tightly.) Then, using new compositions from this converged inner iteration loop, new values for equilibrium ratios are obtained. This procedure is applied directly for the first three iterations of composition. If convergence has not occurred after three iterations, the mole fractions of all components in both phases are accelerated linearly with the deviation function... [Pg.125]

ZO(I) Vector (length 20) of true vapor compositions from previous iteration (I = 1, N). [Pg.300]

Hillger, W. Ultrasonic imaging of defects in Sandwich Composites -from laboratory reseach to in-field inspections, 7 " ECNDT 1998, Copenhagen, Conf. Proc. [Pg.861]

System in which the solid phases consist of the pure components and the components are completely miscible in the liquid phase. We may now conveniently consider the general case of a system in which the two components A and B are completely miscible in the liquid state and the solid phases consist of the pure components. The equilibrium diagram is shown in Fig. 1,12, 1. Here the points A and B are the melting points of the pure components A and B respectively. If the freezing points of a series of liquid mixtures, varying in composition from pure A to pure B, are determined, the two curves represented by AC and BC will be obtained. The curve AC expresses the compositions of solutions which are in equilibrium, at different temperatures, with the solid component A, and, likewise, the curve BC denotes the compositions... [Pg.24]

An adsorbent can be visualized as a porous soHd having certain characteristics. When the soHd is immersed in a Hquid mixture, the pores fill with Hquid, which at equilibrium differs in composition from that of the Hquid surrounding the particles. These compositions can then be related to each other by enrichment factors that are analogous to relative volatiHty in distillation. The adsorbent is selective for the component that is more concentrated in the pores than in the surrounding Hquid. [Pg.291]

Table 16. Char and Gas Composition from Pyrolysis of Municipal Solid Waste Organics ... Table 16. Char and Gas Composition from Pyrolysis of Municipal Solid Waste Organics ...
Poly(vinyl acetate). The dielectric and mechanical spectra of hybrids produced by mixing a poly(vinyl acetate)—THE solution with TEOS, followed by the addition of HCl have been investigated (45). Mixtures were made which were beheved to be 0, 5, 10, 15, and 20 wt % Si02, respectively. These composites were transparent and Eourier transform infrared spectroscopy (ftir) revealed hydrogen bonding between the siUcate network and carbonyl units of the poly(vinyl acetate) (PVAc). No shift in the T of the composites from that of the pure PVAc was observed. Similarly, the activation... [Pg.329]

Table 5. Comparison of Glucomannan Compositions from Various Sources... Table 5. Comparison of Glucomannan Compositions from Various Sources...
Chemical Composition. From the point of view of leathermaking, hides consist of four broad classes of proteins coUagen, elastin, albumen, and keratin (3). The fats are triglycerides and mixed esters. The hides as received in a taimery contain water and a curing agent. Salt-cured cattie hides contain 40—50% water and 10—20% ordinary salt, NaCl. Surface dirt is usuaUy about 2—5 wt %. Cattie hides have 5—15% fats depending on the breed and source. The balance of the hide is protein (1). [Pg.81]

Austenitic steels that are used for nonmagnetic and cryogenic appHcations have lower carbon content than Hadfteld steels and range in composition from 15 to 29% manganese (30). [Pg.496]

Vessel heads can be made from explosion-bonded clads, either by conventional cold- or by hot-forming techniques. The latter involves thermal exposure and is equivalent in effect to a heat treatment. The backing metal properties, bond continuity, and bond strength are guaranteed to the same specifications as the composite from which the head is formed. AppHcations such as chemical-process vessels and transition joints represent approximately 90% of the industrial use of explosion cladding. [Pg.150]

The first commercial plant to use CYANEX 272 became operational in 1985. An additional three plants were constmcted between 1985 and 1989. Of the four, one is in South America and three in Europe. An additional three plants have been built two in Europe (1994) and one in North America (1995). Approximately 50% of the Western world s cobalt is processed using CYANEX 272. Both high purity salts and electrolytic cobalt metal are recovered from solutions ranging in composition from 30 g/L each of cobalt and nickel to 0.2 g/L Co, 95 g/L Ni Operating companies usually regard use of CYANEX 272 as confidential for competitive reasons and identities cannot be disclosed. CYANEX 272 is being evaluated on the pilot-plant scale in many additional projects involving the recovery of cobalt and other metals. [Pg.321]

The H2SO4 catalyst produces a high octane product of similar composition from either 2-butene or 1-butene. This fact suggests that the isomerization of 1-butene to 2-butene is more complete than in the HF system. Isobutylene produces a slightly lower product octane than do the / -butenes. The location of a methyl tert-huty ether [1634-04-4] (MTBE) process upstream of the H2SO4 alkylation unit has a favorable effect on performance because isobutylene is selectively removed from the alkylation feed. [Pg.47]

Process Oils, Plasticizers. Petroleum-based mbber process oils generally contain a mixture of paraffinic, naphthenic, and aromatic components. These oils vary in composition from grade to grade, but most contain some unsaturated moieties and this unsaturation can compete with the polymer for curatives. Therefore, state of cure can be decreased. This is not easily detected because oil softens the compound which masks the loss of state of cure. [Pg.242]

Plasticizers (qv) can range in composition from the ester types, ie, epoxies, phosphate, amides, etc. The effect of any one of these on curing is usually pH-dependent. However, it is pmdent to investigate each on a case by case basis. [Pg.242]

Hydrocarbon solvents marketed by each manufacturer differ ia composition from those of other manufacturers, even if the specification properties are similar. This means that hydrocarbon solvents are not specified on the basis of molecular content. The composition of a hydrocarbon solvent depends on the cmde feed to the process as well as the specific process steps the solvent undergoes duriag manufacture. Because each manufacturer uses a different feed and a somewhat different manufacturiag scheme, hydrocarbon solvents differ somewhat ia thek properties, even ia situations where the solvent performs the same. [Pg.278]

Saline waters, including seawater, contain, besides a variety of inorganic salts, also organic materials and various particles. They differ in composition from site to site, and also change with time as a result of both natural and human causes. Design and operation of desalination plants requires good knowledge of the saline water composition and properties (41,44). [Pg.242]

Fig. 5. The immediate effect of temperature on strength properties of clear wood, expressed as percentage of value at 20°C. Trends illustrated are composites from studies on three strength properties modulus of mpture in bending, tensile strength perpendicular to grain, and compressive strength parallel to grain. VariabiUty in reported results is illustrated by the width of the bands. MC = moisture content. Fig. 5. The immediate effect of temperature on strength properties of clear wood, expressed as percentage of value at 20°C. Trends illustrated are composites from studies on three strength properties modulus of mpture in bending, tensile strength perpendicular to grain, and compressive strength parallel to grain. VariabiUty in reported results is illustrated by the width of the bands. MC = moisture content.
Precipitatioa (2,13—17) techniques employ a combination of nucleation and growth iaduced by adding a chemical precipitant, or by changing the temperature and/or pressure of the solution. Chemical homogeneity is controlled by controlling the rate of precipitation. FFeterogeneous precipitation iavolves the precipitation of a soHd of different composition from the solution, and the composition of the precipitate may change as precipitation continues. Coprecipitation iavolves the simultaneous precipitation of similar size cations ia a salt as a soHd solutioa. [Pg.305]

Preceramic polymer precursors (45,68) can be used to make ceramic composites from polymer ceramic mixtures that transform to the desired material when heated. Preceramic polymers have been used to produce oxide ceramics and are of considerable interest in nonoxide ceramic powder processing. Low ceramic yields and incomplete burnout currently limit the use of preceramic polymers in ceramics processing. [Pg.309]

Table 6. Synthesis Gas Compositions from Gasifiers Operating on Western U.S. Coals... Table 6. Synthesis Gas Compositions from Gasifiers Operating on Western U.S. Coals...
In general, exempt colorants have less coloring power than certified colorants and thus have to be used at higher concentrations. Some, particularly those of plant origin, tend to be less stable, more variable in shade, and therefore more compHcated to use than certified colorants, and are more likely to introduce undeskable flavors and odors into the products in which they are incorporated. Also, depending on thek nature and origin, exempt colorants can vary substantially in composition from batch to batch, are more likely to be contaminated with undeskable trace metals, insecticides, herbicides, and bacteria such as Salmonella and can be more difficult to obtain in steady supply compared with certified colorants. [Pg.447]

The difference between the bounds defined by the simple models can be large, so that more advanced theories are needed to predict the transverse modulus of unidirectional composites from the constituent properties and fiber volume fractions (1). The Halpia-Tsai equations (50) provide one example of these advanced theories ia which the rule of mixtures expressions for the extensional modulus and Poisson s ratio are complemented by the equation... [Pg.11]


See other pages where Compositions from is mentioned: [Pg.125]    [Pg.358]    [Pg.8]    [Pg.99]    [Pg.284]    [Pg.300]    [Pg.324]    [Pg.31]    [Pg.32]    [Pg.423]    [Pg.398]    [Pg.61]    [Pg.220]    [Pg.395]    [Pg.97]    [Pg.370]    [Pg.399]    [Pg.446]    [Pg.448]    [Pg.383]    [Pg.87]    [Pg.163]    [Pg.318]    [Pg.368]    [Pg.130]    [Pg.446]    [Pg.5]    [Pg.339]   
See also in sourсe #XX -- [ Pg.540 , Pg.541 , Pg.542 ]




SEARCH



© 2024 chempedia.info