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Hydration compressibility

When miscible organic solvents are added to aqueous solutions, the dielectric constant (e°) is decreased. This leads to compressed hydrated layers of the proteins, which in its turn allows proteins to interact with each other. The lower the dielectric constant, the more easily this interaction occurs, causing aggregation and predpitation. [Pg.182]

In wetted-wall units, the walls of a tall circular, slightly tapered combustion chamber are protected by a high volume curtain of cooled acid flowing down inside the wall. Phosphoms is atomized by compressed air or steam into the top of the chamber and burned in additional combustion air suppHed by a forced or induced draft fan. Wetted-waU. plants use 25—50% excess combustion air to reduce the tail-gas volume, resulting in flame temperatures in excess of 2000°C. The combustion chamber maybe refractory lined or made of stainless steel. Acid sprays at the bottom of the chamber or in a subsequent, separate spraying chamber complete the hydration of phosphoms pentoxide. The sprays also cool the gas stream to below 100°C, thereby minimising corrosion to the mist-collecting equipment (typically type 316 stainless steel). [Pg.327]

Several alternative methods have been considered in order to increase the energy density of natural gas and facilitate its use as a road vehicle fuel. It can be dissolved in organic solvents, contained in a molecular cage (clathrate), and it may be adsorbed in a porous medium. The use of solvents has been tested experimentally but there has been little improvement so far over the methane density obtained by simple compression. Clathrates of methane and water, (methane hydrates) have been widely investigated but seem to offer little advantage over ANG [4]. Theoretical comparison of these storage techniques has been made by Dignam [5]. In practical terms, ANG has shown the most promise so far of these three alternatives to CNG and LNG. [Pg.274]

In a typical gas oil design, the lighter products overhead from the quench tower/primary fractionator are compressed to 210 psi, and cooled to about 100°F. Some Q plus material is recovered from the compressor knockout drums. The gases are ethanolamine and caustic washed to remove acid gases sulfur compounds and carbon dioxide, and then desiccant dried to remove last traces of water. This is to prevent ice and hydrate formation in the low temperamre section downstream. [Pg.103]

The transition of the compressibility, and other properties of the polyelectrolyte brnshes, is most likely accounted for in terms of the transition in the binding mode of the connterion to the polyelectrolytes, from the loosely bonnd state to the tightly bound one, which rednces inter- and intrachain repulsive interactions. The following snpports this ac-connt (1) At the critical density, = 0.20 chain/nm, the separation distance between polyelectrolyte chains, d, is 2.4 nm. This distance is close to the snm, 2.6 nm, of the chain diameter, 1.3 nm, and the size of two hydrated connterions, 1.32 nm, indicating that the abrupt... [Pg.14]

The addition of STPP (1-7%) acted as a retarder and increased compressive strength (mortar II). Less heat and ammonia were evolved and the cement set more slowly in 10 minutes. The paste hardened in 30 to 60 minutes. Traces of ADP persisted for 30 minutes but no STPP was detected in the reaction products. Struvite, the main hydration product, schertelite and dittmarite all appeared within 5 minutes. Struvite continued to increase in amount as the cement aged schertelite disappeared after 3 hours and dittmarite after a week. Stercorite was found only during the first 7 hours. [Pg.228]

The mainstay of treatment for vaso-occlusive crisis includes hydration and analgesia (see Table 65-7). Pain may involve the extremities, back, chest, and abdomen. Patients with mild pain crises may be treated as outpatients with rest, warm compresses to the affected (painful) area, increased fluid intake, and oral analgesia. Patients with moderate to severe crises should be hospitalized. Infection should be ruled out because it may trigger a pain crisis, and any patient presenting with fever or critical illness should be started on empirical broad-spectrum antibiotics. Patients who are anemic should be transfused to their baseline. Intravenous or oral fluids at 1.5 times maintenance is recommended. Close monitoring of the patient s fluid status is important to avoid overhydration, which can lead to ACS, volume overload, or heart failure.6,27... [Pg.1015]

Soft gelatin capsules are not an inexpensive dosage form, particularly when compared to direct compression tablets [3]. There is a more intimate contact between the shell and its liquid contents than exists with dry-filled hard gelatin capsules, which increases the possibility of interactions. For instance, chloral hydrate formulated with an oily vehicle exerts a proteolytic effect on the gelatin shell however, the effect is greatly reduced when the oily vehicle is replaced with polyethylene glycol [3]. [Pg.375]

Similarly, concepts of solvation must be employed in the measurement of equilibrium quantities to explain some anomalies, primarily the salting-out effect. Addition of an electrolyte to an aqueous solution of a non-electrolyte results in transfer of part of the water to the hydration sheath of the ion, decreasing the amount of free solvent, and the solubility of the nonelectrolyte decreases. This effect depends, however, on the electrolyte selected. In addition, the activity coefficient values (obtained, for example, by measuring the freezing point) can indicate the magnitude of hydration numbers. Exchange of the open structure of pure water for the more compact structure of the hydration sheath is the cause of lower compressibility of the electrolyte solution compared to pure water and of lower apparent volumes of the ions in solution in comparison with their effective volumes in the crystals. Again, this method yields the overall hydration number. [Pg.33]

The apparatus shown in Fig. 2 is assembled in a good hood. One liter of liquid ammonia and 0.5 g. of hydrated ferric nitrate are placed in the 2-1. three-necked flask A, which is equipped with a stirrer and a special reflux condenser cooled with Dry Ice. This condenser is attached to a soda-lime tower which is connected to a source of compressed air through the T-tube C. Over a period of about forty-five minutes, 92 g. (4 gram atoms) of clean sodium shavings is added to the liquid ammonia, and the mixture is stirred until the blue color disappears (one to two hours). [Pg.10]

Gas hydrates are crystalline compounds in which smaller gas molecules (<0.9 nm) are encaged inside the lattices of hydrogen-bonded ice crystals. The gas molecules in the crystalline solids are effectively compressed, volumetrically, by a factor of 164. A comprehensive review of the physical and chemical properties of gas hydrates can be found in Sloan (1998, 2003). [Pg.159]

In the study by Thompson, et al. (11), the ml of gel released per 100 g emulsion for the reference emuTsion without soy, with soy isolate (SIF), soy concentrate (SCF) or soy flour (SF) was 6.07, 5.83, 5.49 and 3.08, respectively, when the hydration ratios were 1 4 (flourrwater) for SIF, 1 3 for SCF and 1 2 for SF. The ml gel released per 100 g emulsion containing 10, 15, 20, and 25% soy protein was 6.70, 5.01, 3.94 and 3.57, respectively. When soy protein concentrate was incorporated into an emulsion at the 3.5% level, the processing yields, textural profile and sensory textural attributes of frankfurters were not different among the products with and without added soy concentrate (13). An objective measure of compression and shear modulus indicated that soy protein concentrate incorporated into frankfurters at the 3.5% level had no effect on batter strength or texture ( M). The addition of a cottonseed protein to frankfurters to replace 5, 10 or 15% of the meat resulted in higher pH, less cured color, less firmness of skin, softer texture and reduced desirability as judged by a sensory panel (J5J. [Pg.86]

In seawater the thickness" of the double layer as given by k1 (Eq. 3.9) is a few Angstroms, equal approximately to a hydrated ion. In other words, the double layer is compressed and hydrophobic colloids, unless stabilized by specific adsorption or by polymers, should coagulate. Some of this coagulation is observed in the estuaries where river water becomes progressively enriched with electrolytes (Fig. 7.14a). That these colloids exist in seawater for reasonable time periods is caused... [Pg.257]


See other pages where Hydration compressibility is mentioned: [Pg.179]    [Pg.329]    [Pg.179]    [Pg.329]    [Pg.30]    [Pg.89]    [Pg.252]    [Pg.52]    [Pg.52]    [Pg.180]    [Pg.547]    [Pg.389]    [Pg.419]    [Pg.290]    [Pg.290]    [Pg.534]    [Pg.235]    [Pg.162]    [Pg.4]    [Pg.583]    [Pg.293]    [Pg.293]    [Pg.251]    [Pg.1199]    [Pg.237]    [Pg.165]    [Pg.50]    [Pg.140]    [Pg.229]    [Pg.283]    [Pg.796]    [Pg.249]    [Pg.249]    [Pg.1282]    [Pg.309]    [Pg.224]    [Pg.89]    [Pg.184]   
See also in sourсe #XX -- [ Pg.61 ]




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